U.S. patent application number 11/632173 was filed with the patent office on 2008-10-16 for heat cloth and process for producing the same.
Invention is credited to Toshihiro Dodo.
Application Number | 20080251062 11/632173 |
Document ID | / |
Family ID | 35783990 |
Filed Date | 2008-10-16 |
United States Patent
Application |
20080251062 |
Kind Code |
A1 |
Dodo; Toshihiro |
October 16, 2008 |
Heat Cloth and Process for Producing the Same
Abstract
To provide a heat cloth which is thin and flexible; even when as
a reaction of an air-permeable heat cloth proceeds, a heat
generating composition becomes massive so that flexibility is
lowered, or a part of an accommodating bag rides up by shrinkage
and curling as caused by heat generation, well keeps the bonding
and holding state so that it does not fall off easily; is supple
like cloths; is excellent in flexing properties; easily and surely
fits to flexible places such as elbows and knees; is able to take
warmth; is applicable with good follow-up deformation properties to
various places of a human body such as curved parts including
shoulders, arms, a neck and feet; and hardly causes an
uncomfortable feeling and a process for producing the same. A heat
cloth having a heat generating composition molded body resulting
from molding a heat generating composition containing surplus water
as a connecting substance accommodated in an accommodating bag,
wherein the accommodating bag is constituted of a substrate and a
covering material; the covering material covers the heat generating
composition molded body as provided on the substrate; the periphery
of the heat generating composition molded body is heat sealed to
form irregularities; sectional exothermic parts of a convex in
which the heat generating composition molded body is accommodated
are disposed while holding a sectioned part of a concave as a heat
seal part; and the exothermic part is formed of a gathering of the
sectional exothermic parts, which is characterized in that the
substrate is substantially planar and does not contain a pocket, an
accommodating division or an accommodating section; that the heat
generating composition contains, as essential components, an iron
powder, a carbon component, a reaction accelerator and water, does
not contain a flocculant aid, a flocculant, an agglomeration aid, a
dry binding material, a dry binding agent, a dry binder, a sticky
raw material, a thickener and an excipient, contains surplus water
so as to have a water mobility value of from 0.01 to 20, with the
water in the heat generating composition not functioning as a
barrier layer, and is capable of causing an exothermic reaction
upon contact with air; that a volume of the heat generating
composition molded body is from 0.1 to 30 cm.sup.3; that a capacity
of the sectional exothermic parts to a ratio of the volume of the
heat generating composition molded body is from 0.6 to 1.0; that a
maximum height of the sectional exothermic parts is from 0.1 to 10
mm; that a width of the sectioned part as a space between the
sectional exothermic parts is from 0.3 to 50 mm; that a minimum
bending resistance on the surface orthogonal to at least a
thickness of the heat cloth is not more than 100 mm; that a part of
the accommodating bag has air permeability; and the surroundings of
the accommodating bag are sealed.
Inventors: |
Dodo; Toshihiro; (Kanagawa,
JP) |
Correspondence
Address: |
KRATZ, QUINTOS & HANSON, LLP
1420 K Street, N.W., Suite 400
WASHINGTON
DC
20005
US
|
Family ID: |
35783990 |
Appl. No.: |
11/632173 |
Filed: |
July 14, 2005 |
PCT Filed: |
July 14, 2005 |
PCT NO: |
PCT/JP2005/013007 |
371 Date: |
January 4, 2008 |
Current U.S.
Class: |
126/263.02 ;
156/60 |
Current CPC
Class: |
C09K 5/18 20130101; F24V
30/00 20180501; A61F 7/034 20130101; A61F 2007/0268 20130101; A61F
2007/0098 20130101; Y10T 156/10 20150115 |
Class at
Publication: |
126/263.02 ;
156/60 |
International
Class: |
F24J 1/00 20060101
F24J001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 14, 2004 |
JP |
2004-207835 |
Claims
1. A heat cloth having a heat generating composition molded body
resulting from molding a heat generating composition containing
surplus water as a connecting substance accommodated in an
accommodating bag, wherein the accommodating bag is constituted of
a substrate and a covering material; the covering material covers
the heat generating composition molded body as provided on the
substrate; the periphery of the heat generating composition molded
body is heat sealed to form irregularities; sectional exothermic
parts of a convex in which the heat generating composition molded
body is accommodated are disposed while holding a sectioned part of
a concave as a heat seal part; and the exothermic part is formed of
a gathering of the sectional exothermic parts, characterized in
that: 1) the substrate is substantially planar and does not contain
a pocket, an accommodating division or an accommodating section, 2)
the heat generating composition contains, as essential components,
an iron powder, a carbon component, a reaction accelerator and
water, does not contain a flocculant aid, a flocculent, an
agglomeration aid, a dry binder, a dry binding agent, a dry binding
material, a sticky raw material, a thickener and an excipient,
contains surplus water so as to have a water mobility value of from
0.01 to 20, with the water in the heat generating composition not
functioning as a barrier layer, and is capable of causing an
exothermic reaction upon contact with air, 3) a volume of the heat
generating composition molded body is from 0.1 to 30 cm.sup.3, 4) a
ratio of the capacity of the sectional exothermic parts to the
volume of the heat generating composition molded body is from 0.6
to 1.0, 5) a maximum height of the sectional exothermic parts is
from 0.1 to 10 mm, 6) a width of the sectioned part as a space
between the sectional exothermic parts is from 0.3 to 50 mm, 7) a
minimum bending resistance on the surface orthogonal to at least a
thickness of the heat cloth is not more than 100 mm, 8) a part of
the accommodating bag has air permeability, and 9) the surroundings
of the accommodating bag are sealed.
2. The heat cloth according to claim 1, characterized in that the
heat generating composition contains a component resulting from a
contact treatment of a mixture containing at least an iron powder,
a carbon component, a reaction accelerator and water as essential
components with an oxidizing gas.
3. The heat cloth according to claim 1, characterized in that the
iron powder comprising particles, a surface of each of which is at
least partially covered with an iron oxide film, the iron oxide
film has a thickness of 3 nm or more, and the iron powder at least
contains from 20 to 100% by weight of an active iron powder
particles having a region of an oxygen-free iron component in at
least one region selected from a central part region of the iron
powder particles and a region beneath the iron oxide film.
4. The heat cloth according to claim 1, characterized in that the
iron powder is covered on at least a part of the surface thereof by
a wustite film and contains from 20 to 100% by weight of an active
iron powder having an amount of wustite of from 2 to 50% by weight
in terms of an X-ray peak intensity ratio to iron.
5. The heat cloth according to claim 1, characterized in that the
heat generating composition molded body is compressed.
6. The heat cloth according to claim 1, characterized in that in
the heat seal part, the heat seal part is formed by heat sealing
after temporary adhesion by an adhesive layer, and an adhesive
component which constitutes the adhesive layer and a heat seal
material component which constitutes the heat seal part are
copresent in at least a part of the heat seal part.
7. The heat cloth according to claim 1, characterized in that after
heat sealing, at least a part of the heat generating composition
molded body is moved to a temporary adhering part which is not heat
sealed, thereby deadhering the temporary adhering part which is not
heat sealed.
8. The heat cloth according to claim 1, characterized in that at
least a part of the air-permeable surface of the exothermic part in
which the sectional exothermic parts are continuously provided is
covered by an air permeability adjusting material.
9. The heat cloth according to claim 1, characterized in that the
sectioned part is provided with a perforation.
10. The heat cloth according to claim 1, characterized in that at
least a part of the sectioned part has an irregular pattern.
11. The heat cloth according to claim 1, characterized in that the
accommodating bag has a fixing measure on at least a part of the
exposed surface thereof.
12. The heat cloth according to claim 11, characterized in that the
fixing measure is an adhesive layer and optionally is provided with
a separator.
13. The heat cloth according to claim 12, characterized in that the
adhesive layer is a hydrophilic adhesive layer, and a packaging
material between the hydrophilic adhesive layer and the heat
generating composition molded body has a moisture permeability of
not more than 2 g/m.sup.2/24 hr.
14. The heat cloth according to claim 12, characterized in that the
adhesive layer has air permeability.
15. The heat cloth according to claim 12, characterized in that the
fixing measure is a sheet-like material in which a non-stretchable
portion and a stretchable portion are integrally formed in a
sheet-like form, and the heat cloth is provided in the
non-stretchable portion of the sheet-like material.
16. The heat cloth according to claim 1, characterized in that the
minimum bending resistance on the surface orthogonal to the
thickness direction of the heat cloth is not more than 100 mm.
17. The heat cloth according to claim 1, characterized in that the
heat generating composition contains at least one member selected
from additional components consisting of a water retaining agent, a
water absorptive polymer, a pH adjusting agent, a hydrogen
formation inhibitor, an aggregate, a fibrous material, a functional
substance, a surfactant, an organosilicon compound, a pyroelectric
substance, a moisturizer, a fertilizer component, a hydrophobic
polymer compound, a heat generating aid, a metal other than iron, a
metal oxide other than iron oxide, an acidic substance, and a
mixture thereof.
18. A process for producing a heat cloth having a heat generating
composition molded body accommodated in an air-permeable
accommodating bag, characterized in that: 1) the accommodating bag
is constituted of a substrate and a covering material; the heat
generating composition molded body is formed by molding a heat
generating composition containing surplus water as a connecting
substance; the covering material covers the heat generating
composition molded body as provided on the substrate; the periphery
of the heat generating composition molded body is heat sealed to
form irregularities; sectional exothermic parts of a convex in
which the heat generating composition molded body is accommodated
are disposed while holding a sectioned part of a concave as a heat
seal part; and the exothermic part is formed of a gathering of the
sectional exothermic parts, 2) the substrate is substantially
planar and does not contain a pocket, an accommodating division or
an accommodating section, 3) the heat generating composition
contains, as essential components, an iron powder, a carbon
component, a reaction accelerator and water, with an amount of
water contained in the heat generating composition being from 1 to
60% by weight, does not contain a flocculant aid, a flocculent, an
agglomeration aid, a dry binding material, a dry binding agent, a
dry binder, a sticky raw material, a thickener and an excipient,
contains surplus water so as to have a water mobility value of from
0.01 to 20, with the water in the heat generating composition not
functioning as a barrier layer, and is capable of causing an
exothermic reaction upon contact with air, 4) a volume of the heat
generating composition molded body is from 0.1 to 30 cm.sup.3, and
a ratio of the capacity of the sectional exothermic parts to the
volume of the heat generating composition molded body is from 0.6
to 1.0, 5) a maximum height of the sectional exothermic parts is
from 0.1 to 10 mm, 6) a width of the sectioned part as a space
between the sectional exothermic parts is from 0.3 to 50 mm, 7) a
minimum bending resistance on the surface orthogonal to at least a
thickness of the heat cloth is not more than 100 mm, 8) a part of
the accommodating bag has air permeability, and 9) the surroundings
of the accommodating bag are sealed.
19. The process for producing a heat cloth according to claim 18,
characterized in that the substrate and the covering material each
have a heat seal layer; an adhesive layer made of an adhesive is
provided on at least one of the heat seal layers; and the substrate
and the covering material are temporarily adhered via the adhesive
layer in the surrounding of the heat generating composition molded
body and then heat sealed.
20. The process for producing a heat cloth according to claim 19,
characterized in that heat sealing is carried out in a width
narrower than that of the temporary adhering seal part, and
thereafter, the heat generating composition is moved into a region
which is not heat sealed within the temporary adhering seal part,
thereby achieving deadhesion.
Description
TECHNICAL FIELD
[0001] The present invention relates to a heat cloth using a heat
generating composition which after producing a heat generation
composition molded body, is capable of causing heat generation
without moving water in the heat generating composition molded body
to a packaging material or a water absorptive sheet, the heat cloth
being soft like fabrics and excellent in flexing properties, easily
and surely fitting to flexible places such as elbows and knees,
being able to take warmth, being applicable with good follow-up
deformation properties to various places of a human body such as
curved parts including shoulders, arms, a neck and feet and hardly
causing an uncomfortable feeling, and to a process for producing
the same.
BACKGROUND ART
[0002] Heat generating compositions utilizing an oxidation reaction
of a metal such as iron have been provided as a powder or granule,
or a viscous material or creamy material. Heat cloths utilizing
such a heat generating composition are very excellent in view of
costs, safety, exothermic temperature, and so on and are already
put into practical use as, for example, a so-called chemical body
warmer as filled in an air-permeable bag.
[0003] In order to obtain a more comfortable feeling for use, there
have been proposed various heat generating compositions which
design to have shape holding properties and to hold exothermic
characteristics while using a thickener, a binding agent, etc. in
quest of prevention of deviation of a heat generating composition
and fitness to various kinds of shapes.
[0004] For example, Patent Document 1 proposes a process for
producing a heat generating composition as granulated so as to have
an average particle size of 0.5 mm or more and a process for
producing a heat generating composition having an improved granular
strength by blending from 10 to 20 parts by weight of an adhesive
binder component in addition water and granulating.
[0005] Also, Patent Document 2 proposes a throwaway body warmer
composed of a heat generating composition having shape holding
characteristics by adding a powdered thickener such as corn starch
and potato starch.
[0006] Also, Patent Document 3 proposes a solid heat generating
composition as prepared by mixing a binding agent such as CMC in a
powdered or granular heat generating composition and compression
molding the mixture.
[0007] Also, Patent Document 4 proposes a heat generating body as
prepared by using a crosslinking agent, etc. and a water absorptive
polymer and integrating them under pressure.
[0008] Also, Patent Document 5 proposes a heat generating
composition in an ink form and/or a creamy form using a thickener
so as to have viscosity, a heat generating body and a process for
producing the same.
[0009] Also, Patent Document 6 proposes a heat generating
composition molded body using a binding agent, the surface of which
is covered by an air-permeable film material such as CMC, thereby
designing to hold the shape.
[0010] Also, Patent Document 7 and Patent Document 8 propose a heat
generating composition as processed into a viscous material or a
creamy material, in which the shape is changed from a conventional
rectangle to a foot shape or an elliptical shape so as to adapt to
the outline of a body to be warmed.
[0011] Also, there is disclosed a heat generating body having a
soft structure in which an exothermic part having a heat generating
composition sealed between packaging materials at least one surface
of which is permeable to air is constituted of plural small
exothermic parts as divided by a seal part.
[0012] Patent Document 9 and Patent Document 10 each discloses a
heat generating body in which a powdered heat generating
composition is filled in sectioned divisions and which is made of
plural exothermic parts as divided by a seal part.
[0013] Also, Patent Document 11, Patent Document 12, Patent
Document 13, Patent Document 14, Patent Document 15 and Patent
Document 16 each propose a heat generating composition using a
flocculant aid and a dry binding agent and a heat generating body
in which a heat generating composition exothermic part is sectioned
into plural divisions by using a substrate having an accommodating
pocket.
[0014] However, following spreading in utilization of throwaway
body warmers which are aimed to be applied to various places of a
human body such shoulders, arms, a neck and feet, even if a heat
generating composition is hardened by a thickener, etc., there were
encountered problems that in a single packed state, for example,
bonding retention is difficult so that the dropping easily occurs
and that a strong uncomfortable feeling is caused in wearing. Such
problems are promoted due to a lowering of flexibility as caused by
blocking following progression of a reaction of heat generating
body. There was also encountered a problem that a stretched film
which forms an accommodating bag is shrunk and curled due to heat
generation so that an end part of a single packaging bag rides up,
whereby a body warmer as bonded and held easily peels away and
drops due to catch therein.
[0015] Furthermore, even if the exothermic part is divided into
plural compartments, a heat generating composition as hardened by a
flocculant aid, etc. involved a problem that an exothermic
performance is deteriorated.
[0016] Furthermore, so far, a heat generating body was produced by
a filling system or produced by filling a heat generating
composition containing a flocculant and a binding agent in a
packaging material having accommodating divisions as molding in
vacuo an agglomerate or compressed body. Moreover, a heat
generating body was produced by previously preparing a filling
pocket in a substrate, filling a heat generating composition in the
pocket and covering a packaging material thereon, followed by
sealing.
[0017] Furthermore, in the case of producing a heat generating body
having sectioned exothermic parts by using a powdered heat
generating composition or a granular heat generating composition as
a heat generating composition, according to a method using a
filling system, since the powdered heat generating composition or
granular heat generating composition is accommodated in an
accommodating body in a partially sealed bag form and the whole is
then sealed, there was a limit in size of a sectional region in
view of the production. That is, according to a method for filling
a powdered heat generating composition or a granular heat
generating composition while partially sealing, it was mechanically
substantially impossible to produce a heat generating body having a
plural number of small-sized sectional regions, and additionally,
there was caused a problem due to shortage in sealing as caused by
incorporation of the heat generating composition into a seal part
or the like. In particular, it was substantially impossible to
continuously produce one having a partial shape having a size of
not more than 20 mm or one having a small shape of not more than 20
mm. Furthermore, according to a method using a rotary magnet system
as disclosed in Patent Document 17, not only a complicated
operation is necessary, but also its structure is complicated.
Accordingly, there were encountered problems that the operation at
the time of forming an exothermic layer is troublesome and that a
device to be used is complicated and expensive, is liable to cause
a fault, takes a long time to do the maintenance and is
inconvenient for handling. Therefore, there was a limit in making
the size of the exothermic part small.
[0018] Furthermore, according to a method using a pocket system, a
heat generating composition containing a flocculant and a binding
agent is used and a dry powdered mixture of an exothermic component
containing a flocculant and a binding agent is filled in a concave
pocket as previously prepared in a packaging material directly or
after compressing it to form a granule, a pellet, a tablet or a
scrub, followed by compression to prepare an exothermic part. Now,
in comparison with a heat generating body in which a flocculant and
a binding agent are not incorporated, in a heat generating body
having plural sectional exothermic parts, the exothermic time is
markedly short, especially, in a sectional exothermic part having a
narrow region whose shortest length is not more than 15 mm or a
sectional exothermic part of a small size, the exothermic duration
is markedly short, resulting in a problem in view of practical use.
If it is intended to prolong the exothermic duration, there was a
problem that it becomes necessary to increase the dimensions of a
single sectioned exothermic part so that the heat generating body
becomes one having a sectional exothermic part of a large size.
Furthermore, even by using a powdered or granular heat generating
composition, there was a problem that a concave pocket must be
previously provided in a packaging material, thereby bringing a
complicated operation. Furthermore, since it is necessary to form a
heat generating composition capable of causing heat generation upon
contact with air by accommodating it in a pocket, sealing the heat
generating composition by a packaging material and then adding
water in the heat generating composition within the pocket, a step
for achieving this must be provided. Thus, the process became
complicated and involved a problem in view of costs.
[0019] [Patent Document 1] JP-A-4-293989
[0020] [Patent Document 2] JP-A-6-343658
[0021] [Patent Document 3] JP-A-59-189183
[0022] [Patent Document 4] WO 00/13626
[0023] [Patent Document 5] JP-A-9-75388
[0024] [Patent Document 6] JP-A-60-101448
[0025] [Patent Document 7] JP-A-9-276317
[0026] [Patent Document 8] JP-A-11-299817
[0027] [Patent Document 9] JP-UM-A-1-110718
[0028] [Patent Document 10] JP-UM-A-6-26829
[0029] [Patent Document 11] JP-A-2000-288008
[0030] [Patent Document 12] JP-T-11-507593
[0031] [Patent Document 13] JP-T-11-508314
[0032] [Patent Document 14] JP-T-11-508786
[0033] [Patent Document 15] JP-T-11-512954
[0034] [Patent Document 16] JP-T-2002-514104
[0035] [Patent Document 17] JP-A-7-124193
DISCLOSURE OF THE INVENTION
Problems that the Invention is to Solve
[0036] An object of the invention is to solve the foregoing
problems and to provide a heat cloth which is thin and flexible;
even when as a reaction of an air-permeable heat cloth proceeds, a
heat generating composition becomes massive so that flexibility is
lowered, or a part of an accommodating bag rides up by shrinkage
and curling as caused by heat generation, well keeps the bonding
and holding state so that it does not fall off easily; is supple
like cloths; is excellent in flexing properties; easily and surely
fits to flexible places such as elbows and knees; is able to take
warmth; is applicable with good follow-up deformation properties to
various places of a human body such as curved parts including
shoulders, arms, a neck and feet; and hardly causes an
uncomfortable feeling and a process for producing the same.
Means for Solving the Problems
[0037] An object of the invention is to solve the foregoing
problems and to provide a heat cloth which is thin and flexible;
even when as a reaction of an air-permeable heat cloth proceeds, a
heat generating composition becomes massive so that flexibility is
lowered, or a part of an accommodating bag rides up by shrinkage
and curling as caused by heat generation, well keeps the bonding
and holding state so that it does not fall off easily; is supple
like cloths; is excellent in flexing properties; easily and surely
fits to flexible places such as elbows and knees; is able to take
warmth; is applicable with good follow-up deformation properties to
various places of a human body such as curved parts including
shoulders, arms, a neck and feet; and hardly causes an
uncomfortable feeling and a process for producing the same.
[0038] Specifically, as set forth in claim 1, a heat cloth of the
invention is a heat cloth having a heat generating composition
molded body resulting from molding a heat generating composition
containing surplus water as a connecting substance accommodated in
an accommodating bag, wherein the accommodating bag is constituted
of a substrate and a covering material; the covering material
covers the heat generating composition molded body as provided on
the substrate; the periphery of the heat generating composition
molded body is heat sealed to form irregularities; sectional
exothermic parts of a convex in which the heat generating
composition molded body is accommodated are disposed while holding
a sectioned part of a concave as a heat seal part; and the
exothermic part is formed of a gathering of the sectional
exothermic parts, which is characterized in that:
1) the substrate is substantially planar and does not contain a
pocket, an accommodating division or an accommodating section, 2)
the heat generating composition contains, as essential components,
an iron powder, a carbon component, a reaction accelerator and
water, does not contain a flocculent aid, a flocculant, an
agglomeration aid, a dry binder, a dry binding agent, a dry binding
material, a sticky raw material, a thickener and an excipient,
contains surplus water so as to have a water mobility value of from
0.01 to 20, with the water in the heat generating composition not
functioning as a barrier layer, and is capable of causing an
exothermic reaction upon contact with air, 3) a volume of the heat
generating composition molded body is from 0.1 to 30 cm.sup.3, 4) a
ratio of the capacity of the sectional exothermic parts to the
volume of the heat generating composition molded body is from 0.6
to 1.0, 5) a maximum height of the sectional exothermic parts is
from 0.1 to 10 mm, 6) a width of the sectioned part as a space
between the sectional exothermic parts is from 0.3 to 50 mm, 7) a
minimum bending resistance on the surface orthogonal to at least a
thickness of the heat cloth is not more than 100 mm, 8) a part of
the accommodating bag has air permeability, and 9) the surroundings
of the accommodating bag are sealed.
[0039] Also, a heat cloth as set forth in claim 2 is characterized
in that in the heat cloth as set forth in claim 1, the heat
generating composition contains a component resulting from a
contact treatment of a mixture containing at least an iron powder,
a carbon component, a reaction accelerator and water as essential
components with an oxidizing gas.
[0040] Also, a heat cloth as set forth in claim 3 is characterized
in that in the heat cloth as set forth in claim 1, the iron powder
comprising particles, a surface of each of which is at least
partially covered with an iron oxide film, the iron oxide film has
a thickness of 3 nm or more, and the iron powder at least contains
from 20 to 100% by weight of an active iron powder particles having
a region of an oxygen-free iron component in at least one region
selected from a central part region of the iron powder particles
and a region beneath the iron oxide film.
[0041] Also, a heat cloth as set forth in claim 4 is characterized
in that in the heat cloth as set forth in claim 1, the iron powder
is covered on at least a part of the surface thereof by a wustite
film and contains from 20 to 100% by weight of an active iron
powder having an amount of wustite of from 2 to 50% by weight in
terms of an X-ray peak intensity ratio to iron.
[0042] Also, a heat cloth as set forth in claim 5 is characterized
in that in the heat cloth as set forth in claim 1, the heat
generating composition molded body is compressed.
[0043] Also, a heat cloth as set forth in claim 6 is characterized
in that in the heat cloth as set forth in claim 1, the heat seal
part is formed by heat sealing after temporary adhesion by an
adhesive layer, and an adhesive component which constitutes the
adhesive layer and a heat seal material component which constitutes
the heat seal part are copresent in at least a part of the heat
seal part.
[0044] Also, a heat cloth as set forth in claim 7 is characterized
in that in the heat cloth as set forth in claim 1, after heat
sealing, at least a part of the heat generating composition molded
body is moved to a temporary adhering part which is not heat
sealed, thereby deadhering the temporary adhering part which is not
heat sealed.
[0045] Also, a heat cloth as set forth in claim 8 is characterized
in that in the heat cloth as set forth in claim 1, at least a part
of the air-permeable surface of the exothermic part in which the
sectional exothermic parts are continuously provided is covered by
an air permeability adjusting material.
[0046] Also, a heat cloth as set forth in claim 9 is characterized
in that in the heat cloth as set forth in claim 1, the sectioned
part is provided with a perforation.
[0047] Also, a heat cloth as set forth in claim 10 is characterized
in that in the heat cloth as set forth in claim 1, at least a part
of the sectioned part has an irregular pattern.
[0048] Also, a heat cloth as set forth in claim 11 is characterized
in that in the heat cloth as set forth in claim 1, the
accommodating bag has a fixing measure on at least a part of the
exposed surface thereof.
[0049] Also, a heat cloth as set forth in claim 12 is characterized
in that in the heat cloth as set forth in claim 11, the fixing
measure is an adhesive layer and optionally is provided with a
separator.
[0050] Also, a heat cloth as set forth in claim 13 is characterized
in that in the heat cloth as set forth in claim 12, the adhesive
layer is a hydrophilic adhesive layer, and a packaging material
between the hydrophilic adhesive layer and the heat generating
composition molded body has a moisture permeability of not more
than 2 g/m.sup.2/24 hr.
[0051] Also, a heat cloth as set forth in claim 14 is characterized
in that in the heat cloth as set forth in claim 12, the adhesive
layer has air permeability.
[0052] Also, a heat cloth as set forth in claim 15 is characterized
in that in the heat cloth as set forth in claim 12, the fixing
measure is a sheet-like material in which a non-stretchable portion
and a stretchable portion are integrally formed in a sheet-like
form, and the heat cloth is provided in the non-stretchable portion
of the sheet-like material.
[0053] Also, a heat cloth as set forth in claim 16 is characterized
in that in the heat cloth as set forth in claim 1, the minimum
bending resistance on the surface orthogonal to the thickness
direction of the heat cloth is not more than 100 mm. Also, a heat
cloth as set forth in claim 17 is characterized in that in the heat
cloth as set forth in claim 1, the heat generating composition
contains at least one member selected from additional components
consisting of a water retaining agent, a water absorptive polymer,
a pH adjusting agent, a hydrogen formation inhibitor, an aggregate,
a fibrous material, a functional substance, a surfactant, an
organosilicon compound, a pyroelectric substance, a moisturizer, a
fertilizer component, a hydrophobic polymer compound, a heat
generating aid, a metal other than iron, a metal oxide other than
iron oxide, an acidic substance, and a mixture thereof.
[0054] Also, as set forth in claim 18, a process for producing a
heat cloth of the invention is a process for producing a heat cloth
having a heat generating composition molded body accommodated in an
air-permeable accommodating bag, which is characterized in
that:
1) the accommodating bag is constituted of a substrate and a
covering material; the heat generating composition molded body is
formed by molding a heat generating composition containing surplus
water as a connecting substance; the covering material covers the
heat generating composition molded body as provided on the
substrate; the periphery of the heat generating composition molded
body is heat sealed to form irregularities; sectional exothermic
parts of a convex in which the heat generating composition molded
body is accommodated are disposed while leaving a sectioned part of
a concave as a heat seal part; and the exothermic part is formed of
a gathering of the sectional exothermic parts, 2) the substrate is
substantially planar and does not contain a pocket, an
accommodating division or an accommodating section, 3) the heat
generating composition contains, as essential components, an iron
powder, a carbon component, a reaction accelerator and water, with
an amount of water contained in the heat generating composition
being from 1 to 60% by weight, does not contain a flocculant aid, a
flocculant, an agglomeration aid, a dry binder, a dry binding
agent, a dry binding material, a sticky raw material, a thickener
and an excipient, contains surplus water so as to have a water
mobility value of from 0.01 to 20, with the water in the heat
generating composition not functioning as a barrier layer, and is
capable of causing an exothermic reaction upon contact with air, 4)
a volume of the heat generating composition molded body is from 0.1
to 30 cm.sup.3, and a ratio of the capacity of the sectional
exothermic parts to the volume of the heat generating composition
molded body is from 0.6 to 1.0, 5) a maximum height of the
sectional exothermic parts is from 0.1 to 10 mm, 6) a width of the
sectioned part as a space between the sectional exothermic parts is
from 0.3 to 50 mm, 7) a minimum bending resistance on the surface
orthogonal to at least a thickness of the heat cloth is not more
than 100 mm, 8) a part of the accommodating bag has air
permeability, and 9) the surroundings of the accommodating bag are
sealed.
[0055] Also, a process for producing a heat cloth as set forth in
claim 19 is characterized in that in the process for producing a
heat cloth as set forth in claim 18, the substrate and the covering
material each have a heat seal layer; an adhesive layer made of an
adhesive is provided on at least one of the heat seal layers; and
the substrate and the covering material are temporarily adhered via
the sticky layer in the periphery of the heat generating
composition molded body and then heat sealed.
[0056] Also, a process for producing a heat cloth as set forth in
claim 20 is characterized in that in the process for producing a
heat cloth as set forth in claim 19, heat sealing is carried out in
a width narrower than that of the temporary adhering seal part, and
thereafter, the heat generating composition is moved into a region
which is not heat sealed within the temporary adhering seal part,
thereby achieving deadhesion.
[0057] Also, in the heat cloth, it is preferable that a thermal
buffer sheet is provided in the central part of the adhesive
layer.
[0058] Also, in the process for producing a heat cloth, it is
preferable that force-through molding or cast molding is employed
for molding the heat generating composition.
[0059] Also, in the process for producing a heat cloth, it is
characterized that the heat generating composition is compressed
within a die.
ADVANTAGES OF THE INVENTION
[0060] As is clear from the foregoing description, the following
advantages are brought.
1. Since the heat cloth of the invention has an exothermic part
resulting from sealing a heat generating composition molded boy
using a heat generating composition by a substrate and a covering
material, which has a thin and fine form and does not deviate the
heat generating composition, it is soft like fabrics and excellent
in flexing properties, easily and surely fits to flexible places
such as elbows and knees, is able to take warmth, is applicable
with good follow-up deformation properties to various places of a
human body such as curved parts including shoulders, arms, a neck
and feet and hardly causes an uncomfortable feeling. Furthermore,
while making the best use of the thin and small-sized shape, the
heat cloth of the invention can be applied to hemorrhagic goods or
sanitary napkins. 2. Since the heat cloth of the invention does not
contain a flocculent aid, a flocculant, an agglomeration aid, a dry
binding material, a dry binding agent, a dry binder, an adhesive
binder, a thickener and an excipient and uses surplus water having
a water mobility value of from 0.01 to 20 to impart moldability, it
is not required to provide an accommodating pocket in the
substrate. Furthermore, the heat cloth of the invention can be
produced by using a substantially planar substrate and is excellent
in exothermic characteristics so that a sufficiently effective
exothermic time can be taken even in the case of an ultra-thin heat
cloth. 3. By combining a temporary adhesion measure, the heat cloth
can be produced at a higher speed. 4. The exothermic part is made
of sectional exothermic parts in a stripe form, and a minimum
bending resistance in one direction on the surface orthogonal to
the thickness direction of the heat cloth is not more than 60 mm.
Thus, the heat cloth of the invention is excellent in adhesion to
curved surfaces of the body. 5. The sectional exothermic parts
constitute a high part, and the sectioned part constitutes a bottom
part; the high part and the low part are alternately present; by
combining an air permeability material, a firm space can be held;
and the space is present along the heat generating composition,
whereby the whole of the heat generating composition can start an
exothermic reaction simultaneously with ventilation. Thus, the heat
cloth could be warmed from the periphery to the central part
thereof without causing uneven temperature, and heat insulation of
the heat generating composition, uniformity of heat generation and
prolongation of an exothermic time could be realized.
[0061] In the light of the above, the invention is able to provide
a heat cloth only by laminating a heat generating composition
molded body resulting from molding a heat generating composition
having surplus water having a water mobility value of from 0.01 to
20 on a substrate, covering a covering material thereon and sealing
at least the periphery of the heat generating composition molded
body, does not require the addition of water after accommodating it
in a packaging material of the substrate or covering material so
that the process is remarkably simplified. Thus, the invention has
superiority in view of costs. That is, the invention is concerned
with a heat cloth using a heat generating composition molded body
resulting from molding a moldable heat generating composition
containing surplus water as a connecting substance, wherein the
heat generating composition does not contain a flocculant aid, a
dry binding agent and a flocculant but contains an appropriate
amount of surplus water as expressed in terms of a water mobility
value as a connecting substance. When an appropriate amount of the
surplus water is contained in the heat generating composition, it
is assumed that the surplus water causes hydration with a
hydrophilic group in the components of the composition by a bipolar
mutual action or hydrogen binding and is present in the
surroundings of a hydrophobic group while having high structural
properties. In this way, it is assumed that a sand dumpling state
is formed, whereby moldability of the heat generating composition
is revealed. This surplus water is connecting water as a connecting
substance for some meaning. Besides, there is water in a state
called as free water. It is thought that when the surplus water
increases, the structure is softened, and free water is observed.
Furthermore, in order that the iron powder causes an oxidation
reaction, the existing amount of water and the feed amount of
oxygen onto the surface of the iron powder become a control factor.
It is said that the water is not sufficient for about an adsorbing
water film (up to 100 angstroms), and an oxidation rate is small.
When the adsorbing film is about 1 .mu.m, not only the amount of
water is sufficient, but also the feed of oxygen onto the surface
of the iron powder is easy because the thickness of the water film
is thin, thereby exhibiting a large oxidation rate. When the film
becomes thicker and the adsorbing film becomes thick exceeding 1
.mu.m, the feed amount of oxygen is reduced. As a result of
obtaining knowledge that one expressing an optimal amount of water
at which moldability and oxidation rate in fixed or higher levels
are exhibited is a water mobility value and is from 0.01 to 20, the
invention has been accomplished. That is, by using an appropriate
amount of surplus water, the particles of the respective components
are secured by a surface tension of the water. Thus, moldability is
revealed in the heat generating composition, and the water does not
function as a barrier layer. Accordingly, the heat generating
composition to be used in the invention comes into contact with air
to cause heat generation. In addition, by using a heat generating
composition using an active carbon powder or an active heat
generating composition, it is possible to use a heat generating
composition having markedly excellent exothermic rising properties
and improved moldability. Furthermore, the heat cloth has two or
more sectional exothermic parts as produced by laminating the heat
generating composition molded body resulting from molding the
moldable heat generating composition on a substantially planar
substrate, further covering the covering material on the heat
generating composition molded body and then heat sealing. It is
possible to provide a heat cloth which is able to cause heat
generation without moving water in the heat generating composition
molded body as produced by a molding and lamination system to the
packaging material or water absorptive sheet, has flexibility by
itself, is excellent in wearing on each place of a human body and
places as required to have flexibility, such as materials having a
curved surface and is excellent in feeling for use and a process
for producing the same. Furthermore, among the substrate, covering
material and heat generating composition molded body, by
temporarily adhering at least the covering material and the heat
generating composition molded body via a sticky layer and then heat
sealing the periphery of the heat generating molded body and the
surroundings of the heat cloth, reliability of the heat sealing is
improved. Thus, it is possible to design to achieve high-speed
production of a heat cloth and make the heat seal width small.
BEST MODES FOR CARRYING OUT THE INVENTION
[0062] The heat cloth of the invention is a heat cloth having a
heat generating composition molded body resulting from molding a
heat generating composition containing surplus water as a
connecting substance accommodated in an accommodating bag, wherein
the accommodating bag is constituted of a substrate and a covering
material; the covering material covers the heat generating
composition molded body as provided on the substrate; the periphery
of the heat generating composition molded body is heat sealed to
form irregularities; sectional exothermic parts of a convex in
which the heat generating composition molded body is accommodated
are disposed while holding a sectioned part of a concave as a heat
seal part; and the exothermic part is formed of a gathering of the
sectional exothermic parts, which is characterized in that:
1) the substrate is substantially planar and does not contain a
pocket, an accommodating division or an accommodating section, 2)
the heat generating composition contains, as essential components,
an iron powder, a carbon component, a reaction accelerator and
water, does not contain a flocculant aid, a flocculant, an
agglomeration aid, a dry binder, a dry binding agent, a dry binding
material, a sticky raw material, a thickener and an excipient,
contains surplus water so as to have a water mobility value of from
0.01 to 20, with the water in the heat generating composition not
functioning as a barrier layer, and is capable of causing an
exothermic reaction upon contact with air, 3) a volume of the heat
generating composition molded body is from 0.1 to 30 cm.sup.3, 4) a
capacity of the sectional exothermic parts to a ratio of the volume
of the heat generating composition molded body is from 0.6 to 1.0,
5) a maximum height of the sectional exothermic parts is from 0.1
to 10 mm, 6) a width of the sectioned part as a space between the
sectional exothermic parts is from 0.3 to 50 mm, 7) a minimum
bending resistance on the surface orthogonal to at least a
thickness of the heat cloth is not more than 100 mm, 8) a part of
the accommodating bag has air permeability, and 9) the surroundings
of the accommodating bag are sealed.
[0063] In addition, in the heat cloth of the invention, for the
purposes of achieving high-speed heat sealing, making the heat seal
width thin and achieving sure heat sealing, there is also employed
heat sealing after temporary adhesion in which the substrate and
the covering material are temporarily adhered via a sticky layer,
followed by heat sealing. That is, the substrate and the covering
material of the air-permeable accommodating bag each have a heat
seal layer; a heat seal part is formed by the heat seal layer; the
heat seal part is formed by heat sealing after temporary adhesion
with an adhesive layer to form a temporary adhering seal; and an
adhesive component which constitutes the adhesive layer and a heat
seal component which constitutes the heat seal layer are copresent
in the heat seal part.
[0064] By making the heat seal part width which sections the
exothermic part thin, a space between the sectional exothermic
parts becomes narrow, a mutual heat insulation effect is kept, and
the exothermic part can be sectioned without causing a lowering of
exothermic characteristics such as a decrease in exothermic time to
be caused due to sectioning of the exothermic part, whereby a heat
cloth having flexibility and excellent exothermic characteristics
can be obtained.
[0065] In the sectional exothermic part or the heat generating
composition molded body of the invention, its maximum width is
usually from 0.5 to 60 mm, preferably from 0.5 to 50 mm, more
preferably from 1 to 50 mm, further preferably from 3 to 50 mm,
still further preferably 3 to 30 mm, even further preferably from 5
to 20 mm, even still further preferably from 5 to 15 mm, and most
preferably from 5 to 10 mm. Furthermore, its maximum height is
usually from 0.1 to 30 mm, preferably from 0.1 to 10 mm, more
preferably from 0.3 to 10 mm, further preferably from 1 to 10 mm,
and still further preferably from 2 to 10 mm. Moreover, its longest
length is usually from 5 to 300 mm, preferably from 5 to 200 mm,
more preferably from 5 to 100 mm, further preferably from 20 to 150
mm, and still further preferably from 30 to 100 mm.
[0066] A capacity of the sectional exothermic part or a volume of
the heat generating composition molded body is usually from 0.015
to 500 cm.sup.3, preferably from 0.04 to 30 cm.sup.3, more
preferably from 0.1 to 30 cm.sup.3, further preferably from 1 to 30
cm.sup.3, and still further preferably from 3 to 20 cm.sup.3.
[0067] In the sectional exothermic part, when the sectional
exothermic part which is an accommodating region of the heat
generating composition is filled with the heat generating
composition molded body, a volume ratio of the volume of the heat
generating composition molded body which is an occupying region of
the heat generating composition molded body to the capacity of the
sectional exothermic part which is an accommodating region of the
heat generating composition is usually from 0.6 to 1, preferably
from 0.7 to 1, more preferably from 0.8 to 1, and further
preferably from 0.9 to 1.0.
[0068] Furthermore, a width of the sectioned part which is a space
between the sectional exothermic parts is not limited so far as
sectioning can be achieved. It is usually from 0.1 to 50 mm,
preferably from 0.3 to 50 mm, more preferably from 0.3 to 50 mm,
further preferably from 0.3 to 40 mm, still further preferably from
0.5 to 30 mm, even further preferably from 1.0 to 20 mm, and even
still further preferably from 3 to 10 mm.
[0069] Incidentally, the heat generating composition molded body or
the sectional exothermic part may have any shape. The shape may be
a planar shape, and examples thereof include a circular shape, an
elliptical shape, a polygonal shape, a star shape, and a flower
shape. Also, the shape may be a three-dimensional shape, and
examples thereof include a polygonal pyramidal shape, a conical
shape, a frustum shape, a spherical shape, a parallelepiped shape,
a cylindrical shape, a semi-pillar shape, a semicylindroid shape, a
semicylidrical shape, a pillar shape, and a cylindroid shape.
Furthermore, in these shapes, the corner may be rounded, thereby
processing the corner in a curvilinear or curved state, or the
central part may be provided with a concave.
[0070] Furthermore, the "volume of the heat generating composition
molded body of the invention" as referred to herein means a volume
of the heat generating composition molded body or compressed heat
generating composition molded body.
[0071] Furthermore, the "capacity of the sectional exothermic part"
as referred to herein means an internal capacity of the sectional
exothermic part having a heat generating composition molded body
accommodated therein.
[0072] In the sectional exothermic part, the accommodating bag, the
outer bag (accommodating bag of the heat generating body), and the
like, packaging materials or the like constituting the same are
sealed in the sectioned part as a seal part or its periphery or
surroundings. Though heat seal is usually employed, other seal
method can be employed depending upon the utility. As one example,
sealing is carried out in a point-like (intermittent) manner or
entirely by compression seal (adhesive seal), warm compression seal
(adhesive seal), bonding seal, heat bonding seal, heat melt seal
(heat seal), etc. by means of pressurizing, warming, heating or a
combination thereof via an adhesive layer and/or a bonding agent
layer and/or a heat seal layer. Selection of any one or a
combination of these methods may be made depending upon the desire.
In this way, it is possible to seal and form a sectional exothermic
part, an inner bag (accommodating bag), an outer bag, etc. Sewing
processing can also be employed as one of seal means.
[0073] A heat cloth in which a number of sectional exothermic parts
are continuously provided and a perforation is provided to a degree
such that cutting by hand is possible in the sectioned part can be
cut into an appropriate size at the time of use on the basis of the
purpose for use adaptive with a place for application of a human
body, or the like and applied. In that case, the size of the heat
cloth and the size and number of the sectional exothermic parts may
be properly set up. There are no limitations regarding such size
and number. Furthermore, the sectioned part can be formed in
arbitrary directions such as a length or width direction, length
and width directions, and an oblique direction.
[0074] Furthermore, at least one surface of a heat generating body
having two or more sectional exothermic parts connected to each
other may be covered by a packaging material. A heat generating
body may be formed by connecting two or more sectional exothermic
parts to each other, or a heat generating body may be formed by
covering at least one surface of the connected sectioned exothermic
parts. As the packaging material, the raw material which is used in
the substrate, the covering material or the underlay material can
be used.
[0075] For example, in the case of using a heat seal
layer-containing film as the packaging material to produce a heat
generating body, a heat generating body may be produced by using a
perforated heat sealable plastic film as an air-permeable packaging
material and sticking a non-woven fabric in the air-permeable side
thereof via an air-permeable adhesive layer, thereby keeping warmth
at the time of use or preventing leakage of collapsed pieces of the
heat generating composition, or a heat generating body for thermal
muffler may be formed by wrapping the both surfaces by a non-woven
fabric, etc.
[0076] At least a part of the surface of the heat generating
composition molded body may be covered by an air-permeable adhesive
layer made of a net-work hot melt based adhesive, etc., or an
underlay material such as a non-woven fabric may be provided
between the air-permeable adhesive layer and the covering
material.
[0077] Furthermore, at least one member of the heat generating
composition molded body, the substrate, the covering material, the
air-permeable adhesive layer, and the underlay material may be
entirely or partly subjected to a pressurizing treatment or
provided with irregularities. In this may, the transfer of the heat
generating composition molded body between the substrate and the
covering material may be prevented.
[0078] That is, a molded body prepared by appropriately compressing
the heat generating composition molded body of the invention under
pressure is markedly improved in moldability. For example, even
when a perforated film which is difficult with respect to the
pressure adjustment is used as a raw material of the air-permeable
part in place of the porous film, in the case where an inner
pressure of the accommodating bag becomes equal to or more than the
outer pressure, shape collapse hardly occurs so that the use of a
perforated film is possible. Accordingly, not only the range for
selecting an air-permeable raw material is widened so that the
costs can be lowered, but also a body to be warmed can be uniformly
warmed at an appropriate temperature over a long period of
time.
[0079] Incidentally, in the case where the heat generating
composition molded body of the invention is compressed, a rate of
compression of the heat generating composition compressed body is
preferably from 50 to 99.5%, more preferably from 60 to 99.5%,
further preferably from 60 to 95%, still further preferably from 65
to 95%, and even further preferably from 70 to 90% in thickness
with respect to the thickness before the compression. Furthermore,
with respect to the thickness before the compression, a thickness
of a die at the time of die molding can be employed.
[0080] In the exothermic part, for the purpose of containing a
magnetic substance in at least a part thereof or one sectional
exothermic part to improve the blood circulation or stiff shoulders
due to a magnetic effect, it is also possible to accommodate
therein a magnetic substance such as a magnet.
[0081] The shape of the heat cloth may be any shape and can be
selected from the group consisting of a rectangular shape, a
circular shape, an elliptical shape, a polygonal shape, a broad
bean-like shape, an eye mask-like shape, a cocoon-like shape, a
gourd-like shape, a rectangular shape with rounded corners, a
square shape with rounded corners, an egg-like shape, a
boomerang-like shape, a comma-shaped bead-like shape, a wing-like
shape, a nose-like shape, a star-like shape, and a foot-like
shape.
[0082] The cross-sectional shape of the sectioned part which is the
seal surface may be formed irregularly, thereby providing a
pattern.
[0083] The cross-sectional shape of the seal surface may be a
planar and plain surface. However, for the purposes of not only
making fashionableness rich and imparting visible pleasant but also
making slipperiness small in forwarding the heat cloth, it is
preferred to form irregularities to provide a pattern.
[0084] It is not always required that this pattern is provided over
the whole of the seal surface. A pattern may be provided only in
the side of the sectional exothermic part, with the remainder being
not provided with a pattern. Inversely, no pattern may be provided
in the side of the sectional exothermic part, with the remainder
being provided with a pattern.
[0085] The pattern on the seal surface is not particularly limited
so far as the cross-sectional shape is irregular. Examples thereof
include an orthogonal lattice shape, a parallel vertical linear
shape, a parallel horizontal linear shape, a zigzag shape, an
oblique lattice shape, a broken oblique linear shape, an oblique
checkerwork shape, and a scattered point shape. FIGS. 14(a) to
14(q) show examples of a specific combination of a pattern and a
plain surface. For example, no pattern may be provided in the side
of the sectional exothermic part, with the central part being
patterned. Inversely, the side of the sectional exothermic part is
patterned, with the remainder as a central part being not provided
with a pattern. The pattern can be arbitrarily chosen. Furthermore,
a pattern in the surroundings as the circumferential part of the
heat cloth is the same.
[0086] A method for providing a pattern on the seal surface is not
limited. Examples thereof include a method in which a pattern
having an irregular cross-sectional shape is provided in a seal
part of a seal bar or a seal roll which is a seal mold and sealing
is carried out using the seal mold.
[0087] Furthermore, the invention is also applicable as a thermal
sheet for operation capable of keep the temperature by warming a
sheet to be covered over the body of a human being during the
operation. In this way, it is possible to prevent the body from the
cold during the operation. Furthermore, by applying heat to a
specific region of the body of a human being who suffers from a
pain, it is possible to remedy an acute or chronic knee including a
muscle, a bone structure and a pain, or the like.
[0088] In the case of application to the body during the operation,
though there are no particular limitations, it is preferable that
heating and heat insulation are preferably carried out for from 0.5
to 24 hours, more preferably from 3 to 24 hours, further preferably
from 6 to 24 hours, and still further preferably from 8 to 16 hours
and that the skin temperature is kept at from about 32.degree. C.
to about 40.degree. C., preferably from about 32.degree. C. to
about 39.degree. C., more preferably from about 32.degree. C. to
about 37.degree. C., and further preferably from about 32.degree.
C. to about 36.degree. C.
[0089] Incidentally, though the size of the sheet is not limited,
it is preferably longitudinal, lightweight and thin.
[0090] Furthermore, by combining the substrate, the covering
material, the heat generating composition and the adhesive layer to
adjust a minimum bending resistance in one direction on the surface
orthogonal to the thickness direction of the heat cloth at not more
than 100 mm, it is possible to prepare a heat cloth having enhanced
adhesion to a body to be warmed such as the body and having an
excellent feeling for use.
[0091] Furthermore, at least one or a part of the substrate, the
covering material, the air permeability adjusting material, the
adhesive layer, and the separator, each of which constitutes the
heat cloth, may be provided with at least one member of characters,
designs, symbols, numerals, patterns, photographs, pictures, and
colors.
[0092] The substrate, the covering material, the air permeability
adjusting material, and the adhesive layer, each of which
constitutes the heat cloth, may be transparent, opaque, colored, or
colorless. Furthermore, a layer constituting at least one layer of
the layers constituting the respective materials and layers may be
colored to a color different from those of other layers.
[0093] The heat generating body is accommodated in an air-tight
air-impermeable accommodating bag, stored and transported. Examples
thereof include a heat generating body prepared by interposing a
produced heat generating body between two sheets of an
air-impermeable film or sheet, punching the two sheets of film or
sheet into a size larger than that of the heat generating body at
the same time with or after this interposition, and sealing the two
sheets of film or sheet in the surroundings exceeding the size of
the heat generating body at the same time with or after this
punching. The outer bag is not limited so far as it is
air-impermeable and may be made of a laminate. Usually, an outer
bag prepared from an air-impermeable raw material is used.
[0094] The accommodating bag of the invention is made of a
substrate and a covering material, and in addition, an underlay
material may be provided between the substrate and the covering
material. Each of the substrate and the covering material is
substantially planar and does not contain a pocket, an
accommodating division or an accommodating section; the covering
material covers the heat generating composition provided on the
substrate; the sectional exothermic part which is constituted by
heat sealing the periphery of the heat generating composition is
made of two or more plural sectional exothermic parts; the
respective exothermic parts are disposed at intervals by the
sectioned part which is a heat seal part; and the exothermic part
is formed of a gathering of the foregoing sectional exothermic
parts. Here, in the invention, the substrate and the covering
material are not distinguished from each other depending upon a raw
material constitution; but a raw material on which the heat
generating composition molded body is laminated is defined as a
substrate, and a raw material which is then covered on the
substrate or heat generating composition molded body is defined as
a covering material.
[0095] A raw material of the substrate or covering material is not
limited so far as it functions as an accommodating bag of the heat
generating composition. Usually, raw materials which are used in
chemical body warmers or heat generating bodies can be used.
Examples of the raw material include air-impermeable raw materials,
air-permeable raw materials, water absorptive raw materials,
non-water absorptive raw materials, non-extensible raw materials,
extensible raw materials, stretchable raw materials,
non-stretchable raw materials, foamed raw materials, non-foamed raw
materials, non-heat sealable raw materials, and heat sealable raw
materials. The raw material can be properly used depending upon a
desired utility in a desired form such as films, sheets, non-woven
fabrics, woven fabrics, and composites thereof.
[0096] In general, the substrate is made of an air-impermeable film
or sheet, and the covering material is made of an air-permeable
film or sheet or non-woven fabric, and vice versa. The both may be
air-permeable. As the underlay material, an air-permeable underlay
material and an air-impermeable underlay material may be used for
different purposes.
[0097] The packaging material of the accommodating bag may be of a
single-layered structure or multilayered structure, and its
structure is not limited. Furthermore, though the packaging
material is composed of at least a substrate and a covering
material, a packaging material for laminating the heat generating
composition molded body is the substrate, and a packaging material
for covering on the heat generating composition molded body is the
covering material regardless of whether the packaging material is
air-permeable or air-impermeable. An embodiment of a multilayered
structure in which an air-impermeable packaging material is the
substrate and an air-permeable packaging material is the covering
material will be hereunder described as one example. That is, in
this embodiment, the substrate is made of layer A/layer B, layer
A/layer B/layer C, or layer A/layer B/layer C/layer D; and the
covering material is made of layer F/layer G, layer E/layer F/layer
G, or layer F/layer H/layer G. Examples of the layer A include
thermoplastic resin films (for example, polyethylene), heat seal
layers (for example, polyethylene and EVA), and water absorptive
papers; examples of the layer B include non-woven fabrics of a
thermoplastic resin (for example, nylons), non-water absorptive
papers, water absorptive papers, thermoplastic resin films (for
example, polyethylene films, polypropylene films, polyester films,
and polyamide (for example, nylons) films), wicks (for example,
non-water absorptive papers and water absorptive papers); examples
of the layer C include adhesive layers, non-water absorptive
papers, water absorptive papers, thermoplastic resin films (for
example, polyethylene), non-slip layers, and non-woven fabrics of a
thermoplastic resin (for example, polyesters and nylons); examples
of the layer D include separators, thermoplastic resin films (for
example, polyethylene), and non-woven fabrics; examples of the
layer E include heat seal layers; examples of the layer F include
porous films or perforated films made of a thermoplastic resin (for
example, polyethylene), films made of a thermoplastic resin (for
example, polyethylene), non-water absorptive papers, and water
absorptive papers; examples of the layer G include non-woven
fabrics of a thermoplastic resin (for example, polyesters and
nylons); and examples of the layer H include non-water absorptive
papers and water absorptive papers. Examples of the substrate or
covering material include heat seal layer made of polyethylene
obtained by using a metallocene catalyst/polypropylene film,
polyethylene-made heat seal layer/polypropylene film, EVA-made heat
seal layer/polypropylene film, EVA-made heat seal
layer/polypropylene film/adhesive layer/separator, EVA-made heat
seal layer/polyethylene film/nylon non-woven fabric, non-woven
fabric/porous film, heat seal layer made of polyethylene obtained
by using a metallocene catalyst/polyethylene film/nylon non-woven
fabric, heat seal layer made of polyethylene obtained by using a
metallocene catalyst/polypropylene film/polypropylene non-woven
fabric, non-woven fabric/(paper and/or perforated (provided by a
needle or laser) film)/porous film, non-woven fabric/(paper and/or
porous film)/perforated (provided by a needle or laser) film, and
non-woven fabric/(paper and/or porous film)/non-woven fabric. A
method for laminating the respective layers is not limited. The
respective layers may be directly laminated; the respective layers
may be laminated via an air-permeable adhesive layer or a
laminating agent layer; and the respective layers may be laminated
by hot melt extrusion or the like. Furthermore, in the invention,
it is to be noted that polyethylene produced by using a metallocene
catalyst is also included in the polyethylene.
[0098] For example, in the case of laminating the foregoing raw
material such as non-woven fabrics and porous films via an
air-permeable sticky layer, examples of a method for forming the
air-permeable sticky layer include a method in which a sticky
substance is fibrillated by an appropriate system such as a curtain
spray system, a melt blow system or a slot spray system for blowing
and spreading a sticky substance via hot air under heat melting and
spread and accumulated on an appropriate supporting substrate made
of a porous film, an air-permeable substrate, a separator, etc.,
thereby forming a porous sticky layer.
[0099] A thickness of each of the substrate, the covering material,
the underlay material, and the raw material constituting the same
varies depending upon the utility and is not limited. The thickness
is usually from 5 to 5,000 .mu.m, preferably from 10 to 500 .mu.m,
and more preferably from 20 to 250 .mu.m.
[0100] The air-impermeable raw material is not limited so far as it
is air-impermeable. Examples thereof include films, sheets or
coatings made of a polymer (for example, polyethylene,
polypropylene, nylons, polyacrylates, polyesters, polyvinyl
alcohols, and ethylene-vinyl acetate copolymers) and laminates
thereof with a metal (including a semiconductor) compound (for
example, silicon oxide) or composite raw materials using the
same.
[0101] Of the foregoing air-impermeable raw materials, examples of
a film having high air impermeability include films provided with a
single layer or multiple layers of a thin film having a metal
including a semiconductor or a compound thereof provided on an
air-impermeable raw material film. Examples of the metal including
a semiconductor include silicon, aluminum, and alloys or mixtures
containing such a metal. Examples of the metal (including a
semiconductor) compound include oxides, nitrides and oxynitrides of
the foregoing metals or alloys or mixtures. Examples of the layer
include silicon oxide layers, aluminum oxide layers, and silicon
oxynitride layers; layers obtained by laminating an arbitrary layer
of these layers on a polyester-made film; and layers obtained by
further laminating a stretched polyolefin film (for example, a
biaxially stretched polypropylene film) thereon.
[0102] The air-permeable raw material is not limited so far as it
is air-permeable. Examples thereof include air-permeable films (for
example, porous films and perforated films); materials having air
permeability by themselves (for example, papers and non-woven
fabrics); materials prepared by laminating at least one of papers
and air-permeable films and non-woven fabrics so as to have air
permeability; materials prepared by providing an air-impermeable
packaging material comprising a non-woven fabric having a
polyethylene film laminated thereon with fine pores by using a
needle, etc. so as to have air permeability; non-woven fabric whose
air permeability is controlled by laminating a fiber and heat
bonding under pressure; porous films; and materials prepared by
sticking a non-woven fabric onto a porous film. The "perforated
film" as referred to herein is a film prepared by providing an
air-impermeable film (for example, polyethylene films) with fine
pores by using a needle so as to have air permeability.
[0103] The air permeability is not limited so far as the heat
generation can be kept. In the case of use in usual heat
generation, the air permeability is usually from 50 to 10,000
g/m.sup.2/24 hr, preferably from 70 to 5,000 g/m.sup.2/24 hr, more
preferably from 100 to 2,000 g/m.sup.2/24 hr, and further
preferably from 100 to 700 g/m.sup.2/24 hr in terms of moisture
permeability by the Lyssy method.
[0104] When the moisture permeability is less 50 g/m.sup.2/24 hr,
the heat value is small and a sufficient thermal effect is not
obtained, and therefore, such is not preferable. On the other hand,
when it exceeds 10,000 g/m.sup.2/24 hr, the exothermic temperature
is high so that a problem in safety may possibly be generated, and
therefore, such is not preferable. However, there is no limitation
even when the moisture permeability exceeds 10,000 g/m.sup.2/24 hr
depending upon the utility, or even in the use at a moisture
permeability closed to the open system, according to
circumstances.
[0105] The stretchable packaging material is not particularly
limited so far as it is stretchable. That is, it is only required
that the stretchable packaging material is stretchable as a whole.
The stretchable packaging material may be formed of a single
material or a composite material of stretchable substrates or a
combination of a stretchable substrate and a non-stretchable
substrate.
[0106] Examples of the stretchable packaging material include
single materials (for example, natural rubbers, regenerated
rubbers, synthetic rubbers, elastomers, and stretchable shape
memory polymers) and mixtures thereof, mixed materials or blended
materials of such a stretchable raw material and a non-stretchable
raw material or fabrics constituted of a combination of these
materials, films, yarns, strands, ribbons, tapes, and stretchable
films with a scrim structure.
[0107] The porous film is not limited and can be properly selected
among porous films obtained by stretching a film made of a
polyolefin based resin (for example, polyethylene, linear low
density polyethylene, and polypropylene) or a fluorine based resin
(for example, polytetrafluoroethylene) and a filler.
[0108] The non-woven fabric is not limited. Single non-woven
fabrics of a single fiber or composite fiber made of a material
such as rayon, nylons (polyamides), polyesters, polyacrylates,
polypropylene, vinylon, polyethylene, polyurethane, cupra, cotton,
cellulose, and pulp, or laminates of blended or accumulated fiber
layers of such fibers are useful. Furthermore, from the standpoint
of production process, dry non-woven fabrics, wet non-woven
fabrics, spunbonds, spunlaces, and the like can be used. Non-woven
fabrics made of a composite fiber having a core-sheath structure
are also useful. A non-woven fabric in the side which is brought
into contact with the skin is preferably a napping (fluffy)
non-woven fabric. Also, stretchable non-woven fabrics and
non-stretchable non-woven fabrics are useful.
[0109] The water absorptive raw material is not particularly
limited so far as it is a water absorptive film or sheet.
[0110] The water absorptive raw material is not particularly
limited so far as it has water absorption properties consequently
regardless of whether or not the raw material has water absorption
properties by itself.
[0111] Specific examples thereof include water absorptive foamed
films or sheets having water absorption properties (for example,
foamed bodies of water absorptive foamed polyurethane, etc.) or
papers, non-woven fabrics or woven fabrics formed of a fiber having
water absorption properties, non-woven fabrics or woven fabrics
containing a fiber having water absorption properties, and water
absorptive materials such as water absorptive porous films or
sheets. Besides, there are enumerated materials in which regardless
of the presence or absence of water absorption properties, a water
absorbing agent is contained, impregnated, kneaded, transferred or
carried on a foamed film or sheet, a non-woven fabric, a woven
fabric or porous film or sheet, thereby imparting or increasing
water absorption properties; and materials in which regardless of
the presence or absence of water absorption properties, a water
absorptive raw material such as water absorptive foamed films or
sheets, papers, non-woven fabrics, woven fabrics, and porous films
or sheets as cut in a planar shape according to the invention is
attached to one side or both sides of the material according to the
invention, thereby imparting water absorption properties.
[0112] In particular, in the heat generating body of the invention,
for the purpose of forming the plane which is brought into contact
with the skin into a comfortable plane by imparting water
absorption properties against sweat, etc., in order that in the
case of sweating, the sweat is absorbed, it is preferable that a
packaging material in the plane which is brought into contact with
the skin is constituted of a packaging material using a non-woven
fabric or a woven fabric containing, as the major component, a
water absorptive fiber having a water retention of 20% or more.
Examples of the water absorptive fiber having a water retention of
20% or more include cottons, silks, hemps, wools, polyacrylonitrile
based synthetic fibers, polyamide based synthetic fibers, polyvinyl
alcohol based synthetic fibers, acetate fibers, triacetate fibers,
and regenerated fibers. In addition, non-woven fabrics having a
highly water absorptive polymer held in a non-woven fabric can be
used as the non-woven fabric having excellent water absorption
properties. Incidentally, non-woven fabrics or woven fabrics
containing such a fiber as the major component are relatively good
with respect to the feeling against the skin.
[0113] In addition, highly water absorptive packaging materials
having high absorption properties of sweat can be used as the
packaging material. Examples thereof include non-woven fabrics
containing a fiber whose surface is coated with a highly water
absorptive resin, non-woven fabrics containing a hollow fiber
having a number of fine pores on the surface thereof, and non-woven
fabrics containing a fiber having a capillary action by forming a
number of pouches or plural layers in the cross-sectional
shape.
[0114] Besides, non-woven fabrics or films having a water
absorptive inorganic compound held on a non-sticky surface of a
packaging material can be used. Examples thereof include non-woven
fabrics resulting from holding a powder (for example, diatomaceous
earth, zeolite, and silica gel) on a non-woven fabric and films
resulting from holding a relatively large amount of a powder (for
example, silica and alumina) on a synthetic resin (for example,
polyethylene).
[0115] In the invention, as a heat seal material constituting a
heat seal layer, a single raw material may be used, or a composite
raw material having a heat seal layer may be used. The heat seal
material is not limited so far as at least a part thereof can be
welded upon heating. Examples thereof include hot melt based resins
such as polyolefins (for example, polyethylene and polypropylene)
or olefin copolymer resins, ethylene based hot melt resins (for
example, ethylene-vinyl acetate copolymer resins and
ethylene-acrylic acid ester copolymer resins (for example,
ethylene-isobutyl acrylate copolymer resins)), polyamide based hot
melt resins, butyral based hot melt resins, polyester based hot
melt resins, polyamide based hot melt resins, polyester based hot
melt resins, polymethyl methacrylate based hot melt resins,
polyvinyl ether based hot melt resins, polyurethane based hot melt
resins, polycarbonate based hot melt resins, such as polyvinyl
acetate, and vinyl chloride-vinyl acetate copolymers; and films or
sheets thereof. Furthermore, in these hot melt based resins or
films or sheets thereof, ones having various additives (for
example, an antioxidant) compounded therein can be used. In
particular, low density polyethylene and polyethylene obtained by
using a metallocene catalyst are useful.
[0116] In the case of interposing a heat generating composition
molded body between a substrate and a covering material, the
"temporary adhesion" as referred to in the invention means weak
pressure-sensitive bonding or adhesion for the purpose of holding
the accommodated heat generating composition molded body until at
least the substrate and the covering material are adhered to each
other via a sticky layer made of an adhesive and heat sealed.
[0117] Furthermore, the "deadhesion" as referred to herein means
that in the temporary adhering seal part after heat seal, the heat
generating composition in a non-heat sealed region is transferred
to the foregoing region, thereby releasing the temporary
adhesion.
[0118] The temporary adhering seal part is formed via a sticky
layer. An adhesive constituting the sticky layer is not limited so
far as it is a layer formed of a polymer composition which is tacky
at the normal temperature and can be heat sealed after the
temporary adhesion.
[0119] Furthermore, although the adhesive of the foregoing adhesive
layer can be used as the adhesive constituting the sticky layer to
be used for the temporary adhesion, a non-hydrophilic adhesive is
preferable. As the adhesive constituting the sticky layer, one
which is well compatible with the heat seal material constituting
the heat seal is preferable, and a melting point of a base polymer
of the adhesive is preferably not higher than a melting point of
the heat seal material. In particular, hot melt based adhesives are
preferable. Furthermore, in the case where the heat seal material
is made of an olefin based raw material, preferred examples of the
adhesive include olefin based adhesives.
[0120] Incidentally, a method for providing a sticky layer for the
temporary adhesion is not limited. The sticky layer may be entirely
provided or partially or intermittently provided. Examples of its
shape include various shapes such as a network-like shape, a
stripe-like shape, a dot-like shape, and strip-like shape.
[0121] The "air-permeable adjusting material" as referred to in the
invention comprises a sectional exothermic part and a sectioned
part and covers an exothermic part having a difference of altitude
via an adhesive layer, etc., thereby adjusting the air permeability
into the sectional exothermic part. That is, in the air
permeability adjusting material, by covering the exothermic part by
the air-permeable adjusting material while utilizing a difference
of altitude between the sectional exothermic part and the sectioned
part, a partitioned space is formed in at least a part of the
periphery of the sectional exothermic part, thereby adjusting the
air permeability between the outside and the sectional exothermic
part and also imparting a heat insulating effect.
[0122] The air permeability of the air permeability adjusting
material is not limited so far as it is able to adjust air
retention or air permeability in at least a part of the periphery
of the sectional exothermic part. However, it is preferable that
the air permeability of the air permeability adjusting material is
lower than that on the air-permeable surface of the sectional
exothermic part as a covering part for covering the heat generating
composition molded body.
[0123] Furthermore, a region where the air permeability is higher
than that in the covering part for covering the heat generating
composition molded body may be provided in a local region of the
air-permeable adjusting material, thereby keeping the air
permeability of other region lower than that on the air-permeable
surface of the sectional exothermic part. In this way, it is
possible to control an air passage for air, etc.
[0124] The fixing region between the air permeability adjusting
material and the exothermic part is not limited so far as the both
can be fixed and air can go in and out from at least the periphery
of the sectional exothermic part. However, the following can be
enumerated.
[0125] 1) The fixing region is fixed in the both ends of the
exothermic part or heat generating body.
[0126] 2) A space is provided entirely in a substantially central
part of the exothermic part, and other exothermic part region is
defined as the fixing region.
[0127] 3) A substantially top part of each sectional exothermic
part and a substantially central part of each sectioned part are
defined as the fixing region.
[0128] Here, as the air permeability adjusting material, any
material can be used so far as it is provided with a space which
communicates with the outside in the surroundings of the sectional
exothermic part. Examples of an air permeability adjusting material
having a bonding layer and utilizing a plastic film include
PE/adhesive, PP/adhesive, polyester/adhesive, PE/non-woven
fabric/air-permeable adhesive, PE/non-woven fabric/PE/adhesive,
PE/PET/M/PE/non-woven fabric/air-permeable adhesive, PE/heat seal
material, PE/non-woven fabric/heat seal material, PE/non-woven
fabric/PE/heat seal material, and PE/polyester/M/PE/non-woven
fabric/heat seal material. Here, M represents a metal (for example,
aluminum and silver), a semiconductor (for example, silicon oxide,
silicon oxynitride, silicon nitride, and aluminum oxide), or a
metal oxide, oxynitride or nitride. Furthermore, a portion for
placing fixing means such as an adhesive layer and a heat sealing
agent layer is not limited, and whether it is provided partially or
entirely may be properly determined depending upon the intended
purpose.
[0129] The bonding layer for fixing the air permeability adjusting
material is not limited so far as the air permeability adjusting
material can be fixed to the heat generating body and is
constituted of a usually used bonding agent or adhesive. In
particular, an adhesive is useful, and the adhesive constituting
the foregoing adhesive layer can be used.
[0130] Furthermore, a method for providing the bonding layer is not
limited so far as the air permeability adjusting material can be
fixed. The bonding layer may be entirely provided or partially or
intermittently provided. Examples of its shape include various
shapes such as a network-like shape, a stripe-like shape, a
dot-like shape, and strip-like shape. Its thickness is not
particularly limited but is in the range of from 5 to 1,000 .mu.m,
preferably from 10 to 500 .mu.m, and more preferably from 15 to 250
.mu.m. When the thickness of the bonding layer is less than 5
.mu.m, a desired adhesive strength may not be possibly obtained. On
the other hand, when it exceeds 1,000 .mu.m, not only it becomes
bulky and becomes worse in feeling for use, but also it becomes
worse in economy, and therefore, such is not preferable.
[0131] Since the heat generating body of the invention has a
bending resistance of not more than 60 mm in at least one
direction, it is flexible, has a degree of adhesion to curved
bodies to be warmed such as the body and is remarkably convenient.
In conventional body warmers, a heat generating composition is
accommodated in a flat accommodating bag. Thus, the conventional
body warmers were not flexible and problematic in adhesion to
curved bodies to be warmed and could not be used in a fitted form.
The heat generating body of the invention is an irregular heat
generating body. Since the concave of the heat generating body of
the invention is flexible, a soft part and a rigid part coexist,
and the heat generating body of the invention has flexibility as a
whole as in cloths.
[0132] Furthermore, by making a bending resistance in one direction
different from that in an orthogonal direction thereto, modulation
of the bending resistance is revealed depending upon the direction
so that handling becomes easy.
[0133] Here, as a process for producing a heat cloth in which an
absolute value of a difference between bending resistances in the
two directions as substantially orthogonal directions becomes
maximal, there is enumerated a production process in which a heat
generating composition molded body having a size of 120 mm in long
side length.times.6 mm in short side length.times.2 mm in height is
prepared by force-through molding; 12 pieces of the heat generating
composition molded body are laminated substantially in parallel at
equal intervals of 10 mm on a substrate made of a laminate of a
nylon-made non-woven fabric and a polyethylene film; an
air-permeable covering material made of a laminate of a nylon-made
non-woven fabric and a polyethylene-made porous film is covered
thereon; the surroundings of 2 mm outside the periphery of each of
the heat generating composition molded bodies are heat sealed in a
width of 4 mm; the outer surroundings of the heat cloth constituted
of the respective heat generating composition molded bodies are
further heat sealed in a width of 8 mm; and the outer surroundings
of the heat cloth are cut while leaving the heat seal, thereby
producing a heat cloth. In a heat cloth as produced by this
production process, an absolute value of a difference between
bending resistances in the two directions as substantially
orthogonal directions becomes maximal. One side of the heat cloth
is flexible and has adhesion, and the other side is rigid and has
nerve. Thus, the heat cloth is very excellent in usefulness.
[0134] The outer bag is not limited so far as it is impermeable to
air, and it may be made of a laminate. Examples thereof include
nylon, polyester and polypropylene films which are subjected to a
moisture-proof treatment with OPP, CPP, polyvinylidene chloride,
metal oxides (including semi-conductors) such as aluminum oxide and
silicon oxide, etc., aluminum foils, and aluminum-deposited plastic
films. As one example thereof, there is enumerated a heat cloth in
which the produced heat cloth is sealed and fixed between two
air-impermeable films or sheets.
[0135] The fixing means is not limited so far as it has capability
for fixing a thermal packaging body for joint surroundings or a
material having an exothermic part to a prescribed part.
[0136] As the fixing means, an adhesive layer, a hook and eye, a
hook and button, a hook and loop fastener such as Velcro, a magnet,
a band, a string, and combination thereof can be arbitrarily
used.
[0137] Incidentally, in the case of a band, fixing means for
adjustment may be further constructed by a combination of a hook
and loop fastener and an adhesive layer.
[0138] Here, the "hook and loop fastener" as referred to herein has
a fastening function by a combination of a loop as a female
fastener with a male fastener capable of fastening the female
fastener thereto, which is known as trade names such as Magic Tape
(a registered trademark), Magic Fastener (a registered trademark),
Velcro Fastener, and Hook and Loop Tape. Examples of the material
having a loop function include non-woven fabrics and woven fabrics
of napped or hole-containing yarns. Such a material having a loop
function (female fastener function) may be covered on the surface
of a paddling forming the band, or the band may be constructed of
such a material itself. Although the hook member which is the male
fastener member is not particularly limited, examples thereof
include hook members formed of a polyolefin based resin (for
example, polyethylene and polypropylene), a polyamide, a polyester,
etc. Although the shape of the hook is not particularly limited, a
hook having a cross-sectional shape such as an I type, an inverted
L type, an inverted J type, and a so-called mushroom type is
preferable because it is easily hooked by the loop and does not
give an extreme stimulus to the skin. Incidentally, the hook may be
adhered to the entire area of a fastening tape, and only the hook
may be used as a fastening tape while omitting a tape
substrate.
[0139] The adhesive layer may contain at least one member selected
from additional components consisting of a water retaining agent, a
water absorptive polymer, a pH adjusting agent, a surfactant, an
organosilicon compound, a hydrophobic polymer compound, a
pyroelectric substance, an antioxidant, an aggregate, a fibrous
material, a moisturizer, a functional substance, and a mixture
thereof.
[0140] The adhesive of the invention is classified into a
non-hydrophilic adhesive, a mixed adhesive, and a hydrophilic
adhesive (for example, a gel).
[0141] The adhesive constituting the adhesive layer is not limited
so far as it has an adhesive strength necessary for adhering to the
skin or clothes. Adhesives of every form such as a solvent based
adhesive, an aqueous adhesive, an emulsion type adhesive, a hot
melt type adhesive, a reactive adhesive, a pressure-sensitive
adhesive, a non-hydrophilic adhesive, and a hydrophilic adhesive
are employable.
[0142] The adhesive layer includes one layer of a non-hydrophilic
adhesive constituted of the non-hydrophilic adhesive and
non-hydrophilic adhesive layers constituted of the non-hydrophilic
adhesive.
[0143] It is to be noted that a material whose water absorption
properties are improving by containing a water absorptive polymer
or a water retaining agent in the non-hydrophilic adhesive layer is
dealt as the non-hydrophilic adhesive layer.
[0144] A hot melt based adhesive may be provided between the
hydrophilic adhesive layer and a substrate or a covering
material.
[0145] Furthermore, in the case where the hydrophilic adhesive is
provided in a thermal packaging body for joint surroundings, there
is no limitation. After seal treating a thermal packaging body for
joint surroundings, a hydrophilic adhesive layer may be provided in
the thermal packaging body for joint surroundings.
[0146] Furthermore, the adhesive layer may or may not have air
permeability and may be properly selected depending upon the
utility. With respect to the air permeability, the adhesive layer
may be air-permeable as a whole. Examples thereof include an
adhesive layer having air permeability as a whole of a region in
which an adhesive is partially present and a portion where no
adhesive is present is partially present.
[0147] In laminating an adhesive on an air-permeable substrate
and/or a covering material in a stratiform state as it is, examples
of a method for keeping its air permeability include a method in
which an adhesive layer is partially laminated by printing or
transferring an adhesive, thereby forming a non-laminated part as
an air-permeable part; a method in which an adhesive is transferred
in one direction while drawing a circle in a filament-like form or
properly moved in the two-dimensional directions by transferring in
a zigzag manner, whereby a space of the filament-like adhesive
keeps air permeability or moisture permeability or the adhesive is
foamed; and a method for forming a layer by a melt blow system.
[0148] Examples of the adhesive which constitutes the
non-hydrophilic adhesive layer include acrylic adhesives, polyvinyl
acetate based adhesives (for example, vinyl acetate resin based
emulsions and ethylene-vinyl acetate resin based holt melt
adhesives), polyvinyl alcohol based adhesives, polyvinyl acetal
based adhesives, vinyl chloride based adhesives, polyamide based
adhesives, polyethylene based adhesives, cellulose based adhesives,
chloroprene (neoprene) based adhesives, nitrile rubber based
adhesives, polysulfide based adhesives, butyl rubber based
adhesives, silicone rubber based adhesives, styrene based adhesives
(for example, styrene based hot melt adhesives), rubber based
adhesives, and silicone based adhesives. Of these, rubber based
adhesives, acrylic adhesives, and adhesives containing a hot melt
based polymer substance for the reasons that they are high in the
adhesive strength, are cheap, are good in long-term stability, and
are small in reduction of the adhesive strength even by providing
heat.
[0149] In addition to the base polymer, if desired, the adhesive
may be compounded with other components such as tackifiers (for
example, petroleum resins represented by rosins, chroman-indene
resins, hydrogenated petroleum resins, maleic anhydride-modified
rosins, rosin derivatives, and C-5 based petroleum resins), phenol
based tackifiers (especially, tackifiers having an aniline point of
not higher than 50.degree. C.; for example, terpene phenol based
resins, rosin phenol based resins, and alkylphenol based resins),
softeners (for example, coconut oil, castor oil, olive oil,
camellia oil, and liquid paraffin), softeners, anti-aging agents,
fillers, aggregates, adhesion adjusting agents, adhesion modifiers,
coloring agents, anti-foaming agents, thickeners, and modifiers,
thereby improving performance such as an improvement in adhesion to
nylon-made clothes and mixed yarn clothes.
[0150] Examples of the hot melt based adhesive include known hot
melt based adhesives imparted with adhesion. Specific examples
thereof include styrene based adhesives made of, as a base polymer,
an A-B-A type block copolymer (for example, SIS, SBS, SEBS, and
SIPS), vinyl chloride based adhesives made of, as a base polymer, a
vinyl chloride resin, polyester based adhesives made of, as a base
polymer, a polyester, polyamide based adhesives made of, as a base
polymer, a polyamide, acrylic adhesives made of, as a base polymer,
an acrylic resin, polyolefin based adhesives made of, as a base
polymer, a polyolefin (for example, polyethylene, super low density
polyethylene, polypropylene, ethylene-.alpha.-olefin copolymers,
and ethylene-vinyl acetate copolymers), 1,2-polybutadiene based
adhesives made of, as a base polymer, 1,2-polybutadiene, and
polyurethane based adhesives made of, as a base polymer,
polyurethane; adhesives made of a modified body of the foregoing
adhesive whose adhesion is improved or whose stability is changed;
and mixtures of two or more kinds of these adhesives. Adhesive
layers constituted of a foamed adhesive and adhesive layers
constituted of a crosslinked adhesive can also be employed.
[0151] The non-aromatic hot melt based adhesive is not limited so
far as it is made of, as a base polymer, a hot melt based adhesive
not containing an aromatic ring. Examples thereof include olefin
based hot melt based adhesives and acrylic hot melt based
adhesives. As the non-aromatic polymer which is the base polymer
not containing an aromatic ring, there are enumerated polymers or
copolymers of an olefin or a diene. Examples thereof include olefin
polymers. The olefin polymer includes polymers or copolymers of
ethylene or an .alpha.-olefin. Also, polymers resulting from adding
a diene (for example, butadiene and isoprene) as other monomer
thereto may be employed.
[0152] The .alpha.-olefin is not limited so far as it is a monomer
having a double bond in the terminal thereof. Examples thereof
include propylene, butene, heptane, hexene, and octene.
[0153] The "aromatic hot melt based adhesive" as referred to herein
is a hot melt based adhesive whose base polymer contains an
aromatic ring. Examples thereof include styrene based hot melt
based adhesives represented by A-B-A type block copolymers.
[0154] In the foregoing A-B-A type block copolymers, the A block is
a non-elastic polymer block made of a monovinyl substituted
aromatic compound A such as styrene and methylstyrene; and the B
block is an elastic polymer block made of a conjugated diene such
as butadiene and isoprene. Specific examples thereof include a
styrene-butadiene-styrene block copolymer (SBS), a
styrene-isoprene-styrene block copolymer (SIS), and hydrogenated
types thereof (for example, SEBS and SIPS), and mixtures
thereof.
[0155] As a countermeasure for preventing a lowering of adhesive
strength caused due to an increase of water of the non-hydrophilic
adhesive layer, an adhesive layer obtained by further compounding a
water absorptive polymer in the non-hydrophilic adhesive can be
used.
[0156] The hydrophilic adhesive which constitutes the hydrophilic
adhesive layer is not particularly limited so far as it contains a
hydrophilic polymer or a water-soluble polymer as the major
component, has adhesion and is hydrophilic as an adhesive.
[0157] Examples of the constitutional components of the hydrophilic
adhesive include hydrophilic polymers (for example, polyacrylic
acid), water-soluble polymers (for example, poly(sodium acrylate)
and polyvinylpyrrolidone), crosslinking agents (for example, dry
aluminum hydroxide and meta-silicic acid aluminic acid metal
salts), softeners (for example, glycerin and propylene glycol),
higher hydrocarbons (for example, soft liquid paraffin and
polybutene), primary alcohol fatty acid esters (for example,
isopropyl myristate), silicon-containing compounds (for example,
silicone oil), fatty acid glycerin esters (for example
monoglycerides), oily components (for example, vegetable oils such
as olive oil), antiseptics (for example, methyl p-hydroxybenzoate
and propyl p-hydroxybenzoate), solubilizing agents (for example,
N-methyl-2-pyrrolidone), thickeners (for example, carboxy-methyl
cellulose), surfactants (for example, polyoxyethylene hardened
castor oil and sorbitan fatty acid esters), hydroxycarboxylic acid
(for example, tartaric acid), excipients (for example, light
silicic anhydride, water absorptive polymers, and kaolin),
moisturizers (for example, D-sorbitol), stabilizers (for example,
sodium edetate, p-hydroxybenzoic acid esters, and tartaric acid),
crosslinking type water absorptive polymers, boron compounds (for
example, boric acid), and water. They may be used as an arbitrary
combination.
[0158] A temporary adhering seal part is formed via a sticky layer.
An adhesive which constitutes the sticky layer is a layer formed of
a polymer composition which is tacky at the normal temperature and
is not limited so far as it can be heat sealed after temporary
adhesion.
[0159] Furthermore, the foregoing adhesives of the sticky layer can
be used as the adhesive which constitutes the sticky layer as used
for temporary adhesion. Of these, non-hydrophilic adhesives are
preferable. With respect to the adhesive constituting the adhesive
layer, it is preferable that the adhesive is well compatible with a
heat seal material constituting a heat seal and that a melting
point of the base polymer of the adhesive is not higher than a
melting point of the heat seal material. Hot melt based adhesives
are especially preferable for hot melt based bonding agents.
Furthermore, in the case where the heat seal material is an olefin
based raw material, preferred examples thereof include olefin based
adhesives.
[0160] A bonding layer for fixing the air permeability adjusting
material is constituted of a bonding agent or an adhesive which is
usually used. In particular, an adhesive is useful, and the
foregoing adhesives for constituting the adhesive layer can be
used.
[0161] Furthermore, a method for providing a bonding layer is not
limited so far as the air permeability adjusting material can be
fixed. The bonding layer may be entirely provided or partially or
intermittently provided. Examples of its shape include various
shapes such as a network-like shape, a stripe-like shape, a
dot-like shape, and strip-like shape.
[0162] Furthermore, in the case where an adhesive layer is employed
as the hydrophilic adhesive layer, if there is a difference in a
water retaining force between the hydrophilic adhesive layer and
the heat generating composition molded body, transfer of water
occurs via a packaging material present therebetween such as a
substrate, thereby causing in-conveniences against the both. In
particular, the transfer of water occurs during the storage. In
order to prevent this, it is preferable that the packaging material
present therebetween at least has a moisture permeability of not
more than 2 g/m.sup.2/day in terms of a moisture permeability
according to the Lyssy method. By using this, in the case where the
heat generating body is accommodated in an outer bag as an
air-impermeable accommodating bag and stored, the transfer of water
can be prevented.
[0163] In the case where a hydrophilic adhesive layer is used as
the adhesive layer, the moisture permeability of a moisture-proof
packaging material provided between the heat generating composition
molded body and the hydrophilic adhesive layer is not limited so
far as the transfer of water can be prevented within the range
where the exothermic performance is not affected. The moisture
permeability according to the Lyssy method is usually not more than
2 g/m.sup.2/day, preferably not more than 1.0 g/m.sup.2/day, more
preferably not more than 0.5 g/m.sup.2/day, and further preferably
from 0.01 to 0.5 g/m.sup.2/day. These values are a value under a
condition under an atmospheric pressure at 40.degree. C. and 90%
RH. Incidentally, the moisture-proof packaging material can be used
as a substrate or a covering material and may be laminated singly
on a substrate, a covering material, or the like.
[0164] The moisture-proof packaging material is not limited so far
as the transfer of water between the heat generating composition
molded body and the hydrophilic adhesive layer can be prevented.
Examples thereof include metal vapor deposited films, vapor
deposited films of a metal oxide, metal foil-laminated films, EVOH
(ethylene/vinyl alcohol copolymer or ethylene/vinyl acetate
copolymer saponified product) based films, biaxially stretched
polyvinyl alcohol films, poly-vinylidene chloride coated films,
polyvinylidene chloride coated films obtained by coating
polyvinylidene chloride on a substrate film (for example,
polypropylene), metal foils such as an aluminum foil,
air-impermeable packaging materials obtained by vapor depositing or
sputtering a metal (for example, aluminum) on a polyester film
substrate, and packaging laminates using a transparent barrier film
of a structure in which silicon oxide or aluminum oxide is provided
on a flexible plastic substrate. The air-impermeable packaging
materials which are used in the outer bag, etc. can also be
used.
[0165] Furthermore, packaging materials such as moisture-proof
packaging materials as described in JP-A-2002-200108, the
disclosures of which can be incorporated herein by reference, can
be used.
[0166] In the case of using a water-containing hydrophilic adhesive
(for example, a gel) in the adhesive layer, in order to adjust the
moisture equilibrium between the heat generating composition and
the adhesive layer, the content of a reaction accelerator (for
example, sodium chloride) or a substance having a water holding
power (for example, a water absorptive polymer) in the heat
generating composition may be adjusted within the range of from 10
to 40% by weight, preferably from 15 to 40% by weight, and more
preferably from 15 to 30% by weight based on the heat generating
composition.
[0167] Furthermore, as the adhesive having good moisture
permeability and low stimulation to the skin, water-containing
adhesives (for example, hydrophilic adhesives and gels) as
described in JP-A-10-265373 and JP-A-9-87173, adhesives which can
be subjected to hot melt coating as described in JP-A-6-145050 and
JP-A-6-199660, and rubber based adhesives as described
JP-A-10-279466 and JP-A-10-182408, the disclosures of which are
totally incorporated herein by reference, are useful.
[0168] The functional substance which is contained in the adhesive
layer is not limited so far as it is a substance having any
function. There can be enumerated at least one member selected from
aromatic compounds, vegetable extracts, crude drugs, perfumes,
slimming agents, analgesics, blood circulation promoters, swelling
improvers, antibacterial agents, sterilizers, mold inhibitors, odor
eaters, deodorants, percutaneously absorptive drugs, fat-splitting
components, minus ion generators, far infrared ray radiants,
magnetic bodies, fomentations, cosmetics, bamboo vinegar, and wood
vinegar.
[0169] Specific examples thereof include aromatic compounds (for
example, menthol and benzaldehyde), vegetable extracts (for
example, mugwort extract), crude drugs (for example, moxa),
perfumes (for example, lavender and rosemary), slimming agents (for
example, aminophylline and tea extract), analgesic drugs (for
example, indomethacin and dl-camphor), blood circulation promoters
(for example, acidic mucopolysaccharide and chamomile), swelling
improvers (for example, horse chestnut extract and flavone
derivatives), fomentations (for example, aqueous boric acid,
physiological saline, and aqueous alcohols), fat-splitting
components (for example, jujube extract, caffeine, and tonalin),
cosmetics (for example, aloe extracts, vitamin preparations,
hormone preparations, anti-histamines, and amino acids),
antibacterial agents and sterilizers (for example, carbolic acid
derivatives, boric acid, iodine preparations, invert soaps,
salicylic acid based substances, sulfur, and antibiotics), and mold
inhibitors.
[0170] The percutaneously absorptive drug is not particularly
limited so far as it has percutaneous absorption. Examples thereof
include corticosteroids, anti-inflammatory drugs, hypertension
drugs, anesthetics, hypnotic sedatives, tranquilizers,
antibacterial substances, antifungal substances, skin stimulants,
inflammation inhibitors, anti-epileptics, analgesics, antipyretics,
anesthetics, mold inhibitors, antimicrobial antibiotics, vitamins,
antiviral agents, swelling improvers, diuretics, antihypertensives,
coronary vasodilators, anti-tussive expectorants, slimming agents,
anti-histamines, antiarrhythmic agents, cardiotonics,
adrenocortical hormones, blood circulation promoters, local
anesthetics, fat-splitting components, and mixtures thereof.
However, it should not be construed that the invention is limited
thereto. These drugs are used singly or in admixture of two or more
kinds thereof as the need arises.
[0171] The content of such a functional substance is not
particularly limited so far as it falls within the range where the
effect of a medicine can be expected. However, from the viewpoints
of adhesive strength as well as pharmacological effect and economy,
the content of the functional substance is preferably from 0.01 to
25 parts by weight, and more preferably from 0.5 to 15 parts by
weight based on 100 parts by weight of the adhesive.
[0172] Furthermore, a method for providing the adhesive layer is
not limited so far as a thermal packaging body for joint
surroundings can be fixed. The adhesive layer may be entirely
provided or partially or intermittently provided. Examples of its
shape include various shapes such as a network-like shape, a
stripe-like shape, a dot-like shape, and strip-like shape.
[0173] The heat generating composition is not limited so far as it
is a heat generating composition which contains, as essential
components, an iron powder, a carbon component, a reaction
accelerator and water, does not contain a flocculant aid, a
flocculant, an agglomeration aid, a dry binding material, a dry
binding agent, a dry binder, an adhesive binder, a thickener and an
excipient, contains surplus water so as to have a water mobility
value of from 0.01 to 20, has moldability due to the surplus water,
with the water in the heat generating composition not functioning
as a barrier layer, and is capable of causing an exothermic
reaction upon contact with air.
[0174] Incidentally, in the invention, what water does not function
as a barrier layer and causes an exothermic reaction upon contact
with air means that water in a heat generating composition does not
function as a barrier layer which is an air intercepting layer and
immediately after the production of a heat generating composition,
comes into contact with air, thereby immediately causing an
exothermic reaction.
[0175] In addition, if desired, at least one member selected from
additional components consisting of a water retaining agent, a
water absorptive polymer, a pH adjusting agent, a hydrogen
formation inhibitor, an aggregate, a fibrous material, a functional
substance, a surfactant, an organosilicon compound, a pyroelectric
substance, a moisturizer, a fertilizer component, a hydrophobic
polymer compound, a heat generating aid, a metal other than iron, a
metal oxide other than iron oxide, an acidic substance, and a
mixture thereof may be further added to the heat generating
composition.
[0176] Furthermore, in the heat generating composition of the
invention or the like, although there is no particular limitation
for the compounding ratio thereof, it is preferred to select the
compounding ratio such that the amount of the reaction accelerator
is from 1.0 to 50 parts by weight, the amount of water is from 1.0
to 60 parts by weight, the amount of the carbon component is from
1.0 to 50 parts by weight, the amount of the water retaining agent
is from 0.01 to 10 parts by weight, the water absorptive polymer is
from 0.01 to 20 parts by weight, the amount of the pH adjusting
agent is from 0.01 to 5 parts by weight, and the amount of the
hydrogen formation inhibitor is from 0.01 to 12 parts by weight,
respectively based on 100 parts by weight of the iron powder; and
that the heat generating composition has a water mobility value of
from 0.01 to 20.
[0177] In addition, the following components may be added in
compounding ratios as described below to the iron powder to the
heat generating composition. That is, the amount of the metal other
than iron is from 1.0 to 50 parts by weight, the amount of the
metal oxide other than iron oxide is from 1.0 to 50 parts by
weight, the amount of the surfactant is from 0.01 to 5 parts by
weight, the amount of each of the hydrophobic polymer compound, the
aggregate, the fibrous material, the functional substance, the
organosilicon compound and the pyroelectric substance is from 0.01
to 10 parts by weight, the amount of each of the moisturizer, the
fertilizer component and the heat generating aid is from 0.01 to 10
parts by weight, and the amount of the acidic substance is from
0.01 to 1 part by weight based on 100 parts by weight of the iron
powder. Incidentally, a magnetic material may further be
compounded, and its compounding ratio may be properly determined
depending upon the desire.
[0178] Incidentally, these compounding ratios can also be applied
in a reaction mixture and a heat generating mixture. Furthermore, a
water mobility value of the reaction mixture is usually less than
0.01.
[0179] As the water, one from a proper source may be employed. Its
purity and kind and the like are not particularly limited.
[0180] In the case of the heat generating composition, the content
of water is preferably from 1 to 70% by weight, more preferably
from 1 to 60% by weight, further preferably from 7 to 60% by
weight, still further preferably from 10 to 50% by weight, and even
further preferably from 20 to 50% by weight of the heat generating
composition.
[0181] Furthermore, in the case of the reaction mixture or heat
generating mixture prior to the contact treatment with an oxidizing
gas, the content of water is preferably from 0.5 to 20% by weight,
more preferably from 1 to 20% by weight, further preferably from 3
to 20% by weight, and still further preferably from 4 to 15% by
weight of the reaction mixture or heat generating mixture.
[0182] The carbon component is not particularly limited so far as
it contains carbon as a component. Examples thereof include carbon
black, graphite, active carbon, carbon nanotubes, carbon nanohorns,
and fullerenes. Carbon which has become conductive by doping or the
like is also employable. There are enumerated active carbons as
prepared from coconut shell, wood, charcoal, coal, bone carbon,
etc. and carbons as prepared from other raw materials such as
animal products, natural gases, fats, oils, and resins. In
particular, active carbons having an adsorption retaining ability
are preferable.
[0183] Furthermore, it is not always required that the carbon
component is present alone. In the case where an iron powder
containing the carbon component and/or covered by the carbon
component is used in the heat generating composition, it is to be
noted that the heat generating composition contains the carbon
component even though the carbon component is not present
alone.
[0184] The reaction accelerator is not particularly limited so far
as it is able to promote the reaction of the heat generating
substance. Examples thereof include metal halides, nitrates,
acetates, carbonates, and metal sulfates. Examples of metal halides
include sodium chloride, potassium chloride, magnetic chloride,
calcium chloride, ferrous chloride, ferric chloride, sodium
bromide, potassium bromide, ferrous bromide, ferric bromide, sodium
iodide, and potassium iodide. Examples of nitrates include sodium
nitrate and potassium nitrate. Examples of acetates include sodium
acetate. Examples of carbonates include ferrous carbonate. Examples
of metal sulfates include potassium sulfate, sodium sulfate, and
ferrous sulfate.
[0185] The water retaining agent is not limited so far as it is
able to retain water. Examples thereof include porous materials
derived from plants having high capillary function and
hydrophilicity such as wood meal, pulp powder, active carbon,
sawdust, cotton cloth having a number of cotton fluffs, short fiber
of cotton, paper dust, and vegetable materials, water-containing
magnesium silicate based clay minerals such as active clay and
zeolite, pearlite, vermiculite, silica based porous substances,
coralline stone, and volcanic ash based substances (for example,
terraballoon, shirasu balloon, and taisetsu balloon). In order to
increase a water retaining ability and enhance a shape holding
ability of such a water retaining agent, the water retaining agent
may be subjected to a processing treatment such as baking and/or
pulverization.
[0186] The water absorptive polymer is not particularly limited so
far as it is a resin having a crosslinking structure and having a
water absorption magnification of ion-exchanged water of 3 times or
more of the dead weight. Furthermore, a water absorptive polymer
the surface of which is crosslinked may be employed. Conventionally
known water absorptive polymers and commercial products may also be
employed.
[0187] Examples of the water absorptive polymer include
poly(meth)acrylic acid crosslinked materials, poly(meth)acrylic
acid salt crosslinked materials, sulfonic group-containing
poly(meth)acrylic ester crosslinked materials, polyoxyalkylene
group-containing poly(meth)acrylic ester crosslinked materials,
poly(meth)acrylamide crosslinked materials, crosslinked materials
of a copolymer of a (meth)acrylic acid salt and a (meth)acrylamide,
crosslinked materials of a copolymer of a hydroxyalkyl
(meth)acrylate and a (meth)acrylic acid salt, polydioxolane
crosslinked materials, crosslinked polyethylene oxide, crosslinked
polyvinylpyrrolidone, sulfonated polystyrene crosslinked materials,
crosslinked polyvinylpyridine, saponification products of a
starch-poly (meth) acrylonitrile graft copolymer,
starch-poly(meth)acrylic acid (salt) graft crosslinked copolymers,
reaction products of polyvinyl alcohol and maleic anhydride (salt),
crosslinked polyvinyl alcohol sulfonic acid salts, polyvinyl
alcohol-acrylic acid graft copolymers, and polyisobutylene maleic
acid (salt) crosslinked polymers. These water absorptive polymers
may be used alone or in combination with two or more kinds
thereof.
[0188] Of these water absorptive polymers, water absorptive
polymers having biodegradation properties are not limited so far as
they are a biodegradable water absorptive polymer. Examples thereof
include polyethylene oxide crosslinked materials, polyvinyl alcohol
crosslinked materials, carboxymethyl cellulose crosslinked
materials, alginic acid crosslinked materials, starch crosslinked
materials, polyamino acid crosslinked materials, and polylactic
acid crosslinked materials.
[0189] The pH adjusting agent is not limited so far it is able to
adjust the pH. Examples thereof include alkali metal weak acid
salts and hydroxides and alkaline earth metal weak acid salts and
hydroxides such as Na.sub.2CO.sub.3, NaHCO.sub.3, Na.sub.3PO.sub.4,
Na.sub.2HPO.sub.4, Na.sub.5P.sub.3O.sub.10, NaOH, KOH,
Ca(OH).sub.2, Mg(OH).sub.2, and Ca.sub.3(PO.sub.4).sub.2.
[0190] The hydrogen formation inhibitor is not limited so far as it
is able to inhibit the formation of hydrogen. Examples thereof
include one member or two or more members selected from the group
consisting of sulfur compounds, oxidizing agents, alkaline
substances, sulfur, antimony, selenium, phosphorus, and tellurium.
Incidentally, examples of sulfur compounds include compounds with
an alkali metal or an alkaline earth metal, metal sulfides such as
calcium sulfide, metal sulfites such as sodium sulfite, and metal
thiosulfates such as sodium thiosulfate.
[0191] Examples of the oxidizing agent include nitrates, oxides,
peroxides, halogenated oxygen acid salts, permanganates, and
chromates.
[0192] The aggregate is not limited so far as it is useful as a
filler and/or is useful for making the heat generating composition
porous. Examples thereof include fossilized coral (for example,
coral fossil and weathered coral fossil), bamboo charcoal, bincho
charcoal, silica-alumina powders, silica-magnesia powders, kaolin,
crystalline cellulose, colloidal silica, pumice, silica gel, silica
powders, mica powders, clays, talc, synthetic resin powders or
pellets, foamed synthetic resins such as foamed polyesters or
polyurethanes, diatomaceous earth, alumina, and cellulose powder.
Incidentally, it is to be noted that kaolin and crystalline
cellulose are not contained in the heat generating composition of
the invention.
[0193] The fibrous material is an inorganic fibrous material and/or
an organic fibrous material. Examples thereof include rock wool,
glass fibers, carbon fibers, metal fibers, pulps, papers, non-woven
fabrics, woven fabrics, natural fibers such as cotton and hemp,
regenerated fibers such as rayon, semi-synthetic fibers such as
acetates, synthetic fibers, and pulverized products thereof.
[0194] The functional substance is not limited so far as it is a
substance having any function. Examples thereof include at least
one member selected from minus ion emitting substances and far
infrared ray radiating substances. The minus ion emitting substance
is not limited so far as it emits a minus ion as a result either
directly or indirectly, and examples thereof include ferroelectric
substances such as tourmaline, fossilized coral, granite, and
calcium strontium propionate, and ores containing a radioactive
substance such as radium and radon. The far infrared ray radiating
substance is not limited so far as it radiates far infrared rays.
Examples thereof include ceramics, alumina, zeolite, zirconium, and
silica.
[0195] The surfactant includes anionic surfactants, cationic
surfactants, nonionic surfactants, and ampholytic surfactants.
Especially, nonionic surfactants are preferable, and examples
thereof include polyoxyethylene alkyl ethers, alkylphenol-ethylene
oxide adducts, and higher alcohol phosphoric acid esters.
[0196] The organosilicon compound is not limited so far as it is a
compound having at least an Si--O--R bond and/or an Si--N--R bond
and/or an Si--R bond. The organosilicon compound is in the form of
a monomer, a lowly condensed product, a polymer, etc. Examples
thereof include organosilane compounds such as
methyltriethoxysilane; and dimethylsilicone oil,
polyorganosiloxane, or silicone resin compositions containing the
same.
[0197] The pyroelectric substance is not limited so far as it has
pyroelectricity. Examples thereof include tourmaline, hemimorphic
ores, and pyroelectric ores. Tourmaline or achroite which is a kind
of tourmaline is especially preferable. Examples of the tourmaline
include dravite, schorl, and elbaite.
[0198] The moisturizer is not limited so far as it is able to hold
moisture. Examples thereof include hyaluronic acid, collagen,
glycerin, and urea.
[0199] The fertilizer component is not limited so far as it is a
component containing at least one of three elements of nitrogen,
phosphorus and potassium. Examples thereof include a bone powder,
urea, ammonium sulfate, calcium perphosphate, potassium chloride,
and calcium sulfate.
[0200] The hydrophobic polymer compound is not limited so far as it
is a polymer compound having a contact angle with water of
40.degree. or more, preferably 50.degree. or more, and more
preferably 60.degree. or more in order to improve the draining in
the composition. The shape of the hydrophobic polymer compound is
not limited, and examples thereof include powdery, particulate,
granular, and tablet shapes. Examples of the hydrophobic polymer
compound include polyolefins such as polyethylene and
polypropylene, polyesters, and polyamides.
[0201] Examples of the heat generating aid include metal powders,
metal salts, and metal oxides such as Cu, Mn, CuCl.sub.2,
FeCl.sub.2, manganese dioxide, cupric oxide, triiron tetroxide, and
mixtures thereof.
[0202] As the metal oxide other than iron oxide, any material can
be employed so far as it does not hinder the oxidation of iron by
an oxidizing gas, and examples thereof include manganese dioxide
and cupric oxide.
[0203] The acidic substance may be any of an inorganic acid, an
organic acid, or an acidic salt. Examples thereof include
hydrochloric acid, sulfuric acid, nitric acid, acetic acid, oxalic
acid, citric acid, malic acid, maleic acid, chloroacetic acid, iron
chloride, iron sulfate, iron oxalate, iron citrate, aluminum
chloride, ammonium chloride, and hypochlorous acid.
[0204] As the "iron powder" as referred to herein, usual iron
powders, iron alloy powders and active iron powders such as iron
powders comprising particles, a surface of each of which is at
least partially covered with an oxygen-containing film, and iron
alloy powders comprising particles, a surface of each of which is
at least partially covered with an oxygen-containing film, are
preferable. Incidentally, the "iron oxide film" as referred to
herein is a film made of oxygen-containing iron such as iron oxide,
hydroxide or oxyhydroxide. Furthermore, the "active iron powder" as
referred to herein is a powder in which an iron oxide film is
formed at least locally on the surface of an iron powder, from
which an oxidation reaction promoting effect is obtained by a local
cell as formed between an iron matrix and an iron oxide film or a
pit inside and outside the iron oxide film.
[0205] The iron powder is not limited, and examples thereof include
cast iron powders, atomized iron powders, electrolyzed iron
powders, reduced iron powders, sponge iron powders, and iron alloy
powders thereof. In addition, the iron powder may contain carbon or
oxygen, and an iron powder containing 50% or more of iron and other
metals may be employed. The kind of the metal which is contained as
an alloy, etc. is not particularly limited so far as the iron
component works as a component of the heat generating composition.
Examples of such a metal include metals such as aluminum,
manganese, copper, nickel, silicon, cobalt, palladium, and
molybdenum, and semiconductors. The metal of the invention includes
a semiconductor. Such a metal or alloy may be contained only in the
surface or the interior, or may be contained in both the surface
and the interior.
[0206] In the iron powder of the invention, the content of the
metal other than iron is usually from 0.01 to 50% by weight, and
preferably from 0.1 to 10% by weight based on the whole of the iron
powder.
[0207] Examples of the iron powder having an oxygen-containing film
on at least a part of the surface of the iron include:
[0208] (A) an active iron powder in which the surface of an iron
component is at least partially oxidized, which is obtained by
contact treating the essential components of the heat generating
composition or the essential components to which acidic substances
or other necessary components are added with an oxidizing gas,
thereby partially oxidizing the iron component;
[0209] (B) an active iron powder in which the content of wustite is
from 2 to 50% by weight in terms of an X-ray peak intensity ratio
to iron;
[0210] (C) an iron powder having an iron oxide film having a
thickness of 3 nm or more on the surface thereof; and
[0211] (D) a mixture of an active iron powder and an iron powder
other than an active iron powder.
[0212] With respect to (A), although the mechanism is not
elucidated in detail, it is assumed that upon contact between the
oxidizing gas and the components, not only an iron oxide film,
namely, an oxygen-containing film is formed on the surface of the
iron powder due to the oxidation of the components, especially the
oxidation of the iron powder, but also the surface of active carbon
is oxidized and/or the oxidized iron component is adhered, whereby
hydrophilicity is imparted or improved, and coupling between the
components or structurization takes place through the mediation of
water.
[0213] That is, it is assumed that some kind of a change in the
function occurs such that an iron oxide film is formed on the
surface of the iron powder, the shape of the iron powder particle
becomes irregular, a strain is generated due to the oxidation, or a
water-containing pit is formed, whereby the iron powder is
activated and exothermic rising properties are improved.
[0214] Furthermore, the case where magnetite (Fe.sub.3O.sub.4) is
present in the iron oxide film is preferable because the
conductivity is excellent, and the case where hematite
(Fe.sub.2O.sub.3) is present in the iron oxide film is also
preferable because the iron oxide film becomes porous. Moreover, it
is assumed that the carbon component is oxidized on the surface
thereof and becomes a carbon component which is rich in oxides on
the surface thereof, whereby the hydrophilicity increases and the
activity increases.
[0215] The thickness of the iron oxide film which is an
oxygen-containing film covering the surface of the iron powder, as
measured by the Auger electron spectroscopy, is usually 3 nm or
more, preferably from 3 nm to 100 .mu.m, more preferably from 30 nm
to 100 .mu.m, further preferably from 30 nm to 50 .mu.m, still
further preferably from 30 nm to 1 .mu.m, even further preferably
from 30 nm to 500 nm, and even still further preferably from 50 nm
to 300 nm.
[0216] When the thickness of the oxygen-containing film of iron is
3 nm or more, the thickness of the oxygen-containing film of iron
is able to exhibit a promoting effect of the oxidation reaction,
and upon contact with an oxidizing gas such as air, is able to
immediately initiate the oxidation reaction. When the thickness of
the oxygen-containing film of iron is 100 .mu.m or more, though the
heat generation time may possibly be shortened, such is applicable
depending upon the utility.
[0217] Furthermore, according to the active iron powder, by using a
reaction mixture containing, as essential components, an iron
powder, a reaction accelerator and water and having a water content
of from 0.5 to 20% by weight and a water mobility value showing a
surplus water content of less than 0.01, the reaction rate at the
time of the contact treatment with an oxidizing gas can be raised,
thereby achieving a time required for regulating a temperature rise
of the reaction mixture at 1.degree. C. or more within 10 minutes.
By shortening a time required for arrival at a prescribed
temperature or higher, proper activation can be achieved, and
unnecessary oxidation on the iron powder can be prevented.
[0218] Furthermore, the heat generating composition prepared by
adding a carbon component, etc. to a heat generating mixture as
produced by contact treating the reaction mixture with an oxidizing
gas or adjusting the water content so as to have a water mobility
value of from 0.01 to 50 is properly tacky, has excellent
moldability and is able to be applied with a molding method such as
a force-through die molding method and a cast molding method,
whereby heat generating bodies of various shapes can be produced.
In particular, a heat generating composition having a water
mobility value of from 0.01 to 20 is excellent because it initiates
an exothermic reaction immediately after contacting with air, has
excellent exothermic rising properties and has excellent
moldability.
[0219] The contact treatment method of the reaction mixture with an
oxidizing gas is not particularly limited so far as it is able to
contact treat a reaction mixture containing, as essential
components, an iron powder, a reaction accelerator and water and
having a water content of from 0.5 to 20% by weight and a water
mobility value of less than 0.01 with an oxidizing gas and regulate
a temperature rise of the reaction mixture at 1.degree. C. or
more.
[0220] Specific examples thereof include:
[0221] (1) a process for producing a heat generating mixture
containing an iron powder having an iron oxide film on the surface
thereof by subjecting a reaction mixture of an iron powder, a
reaction accelerator and water in an oxidizing gas atmosphere to a
self-exothermic reaction, thereby partially oxidizing the iron
powder;
[0222] (2) a process for producing a heat generating mixture by
subjecting a reaction mixture of an iron powder, a reaction
accelerator, an acidic substance and water in an oxidizing gas
atmosphere to a self-exothermic reaction;
[0223] (3) a process for producing a heat generating mixture by
subjecting a reaction mixture of an iron powder, a reaction
accelerator, a carbon component and water in an oxidizing gas
atmosphere to a self-exothermic reaction;
[0224] (4) a process for producing a heat generating mixture by
subjecting a reaction mixture of an iron powder, a reaction
accelerator, an acidic substance, a carbon component and water in
an oxidizing gas atmosphere to a self-exothermic reaction;
[0225] (5) a process for producing a heat generating mixture
containing a partially oxidized iron powder by carrying out the
method as set forth above in any one of (1) to (4), wherein the
reaction mixture or heat generating mixture as set forth above in
any one of (1) to (4) contains a component other than the foregoing
components;
[0226] (6) a process for producing a heat generating mixture by
carrying out the method as set forth above in any one of (1) to (5)
under circumstances heated so as to have temperature of at least
10.degree. C. higher than the circumferential temperature;
[0227] (7) a process for producing a heat generating mixture by
carrying out the method as set forth above in any one of (1) to (6)
by blowing an oxidizing gas;
[0228] (8) a process for producing a heat generating mixture by
carrying out the method as set forth above in (7) by blowing the
oxidizing gas heated so as to have a temperature of at least
10.degree. C. higher than the circumferential temperature;
[0229] (9) a process for producing a heat generating composition by
carrying out the method as set forth above in any one of (1) to (8)
by contact treating with an oxidizing gas until the temperature
exceeds a maximum temperature which is a maximum point of
temperature rise by the exothermic reaction;
[0230] (10) a process for producing a heat generating mixture by
carrying out the method as set forth above in any one of (1) to (8)
by contact treating with an oxidizing gas until the temperature
exceeds a maximum temperature by the exothermic reaction and drops
by at least 10 to 20.degree. C. from the maximum temperature;
[0231] (11) a process for producing a heat generating composition
by carrying out the method as set forth above in any one of (1) to
(8) by contact treating with an oxidizing gas until the temperature
exceeds a maximum temperature which is a maximum point of
temperature rise by the exothermic reaction and after intercepting
the oxidizing gas, holding it until the temperature of at least the
reaction mixture drops by at least 10 to 20.degree. C. from the
maximum temperature; and
[0232] (12) a process for producing a heat generating mixture by
heating the reaction mixture or heat generating mixture as set
forth above in any one of (1) to (5) under oxidizing gas
circumstances while regulating a temperature rise at 1.degree. C.
or more.
[0233] In addition, a heat generating mixture as prepared by adding
other components to the heat generating mixture and further
treating with an oxidizing gas may be employed.
[0234] Incidentally, the circumstances of the reaction mixture at
the time of contact treatment with an oxidizing gas are not limited
so far as the reaction mixture is brought into contact with an
oxidizing gas under circumstances of 0.degree. C. or higher and a
temperature rise of the reaction mixture is regulated at 1.degree.
C. or more within 10 minutes. In the case where the contact
treatment is carried out in an open system, the circumstances may
be either the state that the reaction mixture is present in a
lid-free vessel or the state that an oxidizing gas such as air
comes into a vessel through an air-permeable sheet-like material
such as non-woven fabrics.
[0235] Furthermore, the contact treatment with an oxidizing gas may
be carried out with or without stirring in a fluidized or
non-fluidized state and may be carried out in a batch or continuous
system.
[0236] Examples of the final heat generating composition
include:
[0237] 1) a heat generating composition containing, as a heat
generating composition raw material, a heat generating mixture
produced in the process as set forth above in any one of (1) to
(12);
[0238] 2) a heat generating composition obtained by adding other
components to the heat generating composition as set forth above in
1); and 3) a heat generating composition obtained by adjusting the
water content of the heat generating composition as set forth above
in 1) or 2).
[0239] The order of the timing of adding other components than the
essential components and the timing of adjusting the water content
is not limited.
[0240] Here, the water content in the reaction mixture and also the
heat generating mixture prior to the treatment with an oxidizing
gas is usually from 0.5 to 20% by weight, preferably from 1 to 15%
by weight, more preferably from 2 to 10% by weight, further
preferably from 3 to 10% by weight, and still further preferably
from 6 to 10% by weight.
[0241] The temperature of the reaction mixture after the contact
with an oxidizing gas is not limited so far as the temperature rise
is regulated at 1.degree. C. or more. The temperature of the
reaction mixture after the contact with an oxidizing gas is
preferably from 1 to 80.degree. C., more preferably from 1 to
70.degree. C., further preferably from 1 to 60.degree. C., and
still further preferably from 1 to 40.degree. C.
[0242] The circumferential temperature at the time of contact
between the reaction mixture and the oxidizing gas is not limited
so far as the temperature of the reaction mixture is raised to a
prescribed temperature or higher. The circumferential temperature
at the time of contact between the reaction mixture and the
oxidizing gas is preferably 0.degree. C. or higher, more preferably
from 0 to 250.degree. C., further preferably from 10 to 200.degree.
C., still further preferably from 20 to 150.degree. C., even
further preferably from 25 to 100.degree. C., and even still
further preferably from 25 to 50.degree. C.
[0243] The time of contact between the reaction mixture and the
oxidizing gas is not limited so far as the time required for
regulating a temperature rise at 1.degree. C. or more is within 10
minutes. The time of contact between the reaction mixture and the
oxidizing gas is preferably from one second to 10 minutes, more
preferably from one second to 7 minutes, further preferably from
one second to 5 minutes, still further preferably from 2 seconds to
5 minutes, even further preferably from 2 seconds to 3 minutes, and
even still further preferably from 2 seconds to one minute.
[0244] The temperature of the oxidizing gas is not limited so far
as the foregoing circumferential temperature is kept.
[0245] As the "oxidizing gas" as referred to herein, any gas can be
used as the oxidizing gas so far as it is oxidizing. Examples
thereof include an oxygen gas, air, and mixed gases of an inert gas
(for example, a nitrogen gas, an argon gas, and a helium gas) and
an oxygen gas. Although the mixed gas is not limited so far as it
contains oxygen, mixed gases containing 10% or more of an oxygen
gas are preferable, and of these, air is especially preferable. If
desired, a catalyst such as platinum, palladium, iridium, and
compounds thereof can also be used.
[0246] The oxidation reaction can be carried out under stirring in
an oxidizing gas atmosphere optionally under a pressure and/or upon
irradiation of ultrasonic waves.
[0247] The optimal condition of the oxidation reaction may be
properly experimentally determined.
[0248] An amount of the oxidizing gas to be used is not limited but
may be adjusted depending upon the kind of the oxidizing gas, the
kind and particle size of the iron powder, the water content, the
treatment temperature, the treatment method, and the like.
[0249] In the case of an open system, there is no limitation so far
as a necessary amount of oxygen can be taken in. In order to
prevent fly of the reaction mixture or contamination of dusts,
etc., the system may be surrounded by an air-permeable raw material
such as non-woven fabrics and woven fabrics. So far as the system
is in an air-permeable state, it is to be noted that the system is
an open system.
[0250] In the case where air is used in the system of blowing an
oxidizing gas, for example, the amount of air is preferably from
0.01 to 1,000 L/min, more preferably from 0.01 to 100 L/min, and
further preferably from 0.1 to 50 L/min per 200 g of the iron
powder under one atmosphere. In the case of other oxidizing gas,
the amount of the oxidizing gas may be converted on the basis of
the case of air.
[0251] If desired, a peroxide may be added. Examples of the
peroxide include hydrogen peroxide and ozone.
[0252] Here, so far as the iron powder is partially oxidized, the
state of the reaction mixture or heat generating mixture at the
time of the contact treatment with an oxidizing gas may be any of a
standing state, a transfer state, or a fluidizing state by
stirring, etc. and may be properly selected. Furthermore, the
circumstances at the time of mixing the respective components of
the reaction mixture, the heat generating mixture or the heat
generating composition and at the time of the contact treatment
with a mixed oxidizing gas at the time of adjusting the water
content are not limited, and examples thereof include those in an
oxidizing gas atmosphere and those in blowing of an oxidizing
gas.
[0253] A method for measuring a temperature rise of the heat
generating composition is as follows.
[0254] 1) A heat generating composition is allowed to stand in a
state that it is sealed in an air-impermeable outer bag for one
hour under a condition that the circumferential temperature is
20.+-.1.degree. C.
[0255] 2) A magnet is provided in the vicinity of a central part of
the back side of a polyvinyl chloride-made supporting plate (3 mm
in thickness.times.600 mm in length.times.600 mm in width) of a
footed supporting table so as to cover a cavity shape of a molding
die.
[0256] 3) A temperature sensor is placed on the central part of the
supporting plate.
[0257] 4) A polyethylene film (25 .mu.m in thickness.times.250 mm
in length.times.200 mm in width) as provided with an adhesive layer
having a thickness of about 80 .mu.m is stuck onto the supporting
plate via a sticky layer such that the center of the polyethylene
film is positioned at the sensor.
[0258] 5) The heat generating composition is taken out from the
outer bag.
[0259] 6) A template (250 mm in length.times.200 mm in width)
having a cavity (80 mm in length.times.50 mm in width.times.3 mm in
height) is placed above the central part of the polyethylene film;
a sample is placed in the vicinity of the cavity; a force-in die
plate is moved along the template; the sample is charged into the
cavity while stuffing; and the sample is leveled while stuffing
along the template plane (force-in die molding), thereby filling
the sample in the die. Next, the magnet beneath the supporting
plate is removed, and the temperature measurement is started.
[0260] With respect to the measurement of the exothermic
temperature, the temperature is measured for 10 minutes at a
measurement timing of 2 seconds using a data collector, and
exothermic rising properties are judged in terms of the temperature
after elapsing 3 minutes.
[0261] The heat generation test of the heat generating body follows
the JIS temperature characteristic test.
[0262] In the iron powder or active iron powder in the oxidizing
gas-treated heat generating composition, at least a part of the
surface thereof is covered by an oxygen-containing film of iron.
The degree of covering on the surface of the oxygen-containing film
of iron is not limited so far as at least a part of the surface
thereof is covered, and the surface may be entirely covered. In the
case of the heat generating composition of the invention, since an
ion of the reaction accelerator such as a chlorine ion is contained
in the heat generating composition, there is no corrosion effect of
the oxide film due to anti-corrosion effect by the ion of the
reaction accelerator such as a chlorine ion. Thus, the oxidation
reaction which is a sort of corrosion is not hindered. In
particular, in the case where an oxygen-containing film of iron is
prepared while the ion of the reaction accelerator such as a
chlorine ion exists together, the subject effect is large. In the
case where a metal other than iron is present on the surface, it is
only required that at least other part of the metal portion other
than iron is covered by the oxygen-containing film of iron.
[0263] In the iron powder of the invention, not only a region where
(1) entire (uniform) corrosion, (2) pitting or crevice corrosion,
(3) stress corrosion cracking, or the like is generated, but also
irregularities or crevices are formed. For that reason, it is
assumed that the iron powder of the invention has hydrophilicity
and oxidation catalytic properties (FeO, etc.) in its own portion.
In producing the heat generating composition, it is important that
the iron powder has an oxygen-containing film in its own portion
without relying upon mixing. In particular, in the iron component
as prepared by contact treating the iron component and the reaction
accelerator and water as essential components with an oxidizing
gas, it is thought that a reaction active part composed mainly of
an oxide, a hydroxide, a chlorine ion, a hydrogen ion, etc. is
formed, whereby exothermic reactivity and hydrophilicity are
improved and exothermic rising properties and moldability are
remarkably improved.
[0264] With respect to (B), the amount of FeO (wustite) which is
contained in the iron component containing a prescribed amount of
wustite is usually from 2 to 50% by weight, preferably from 2 to
40% by weight, more preferably from 2 to 30% by weight, further
preferably from 5 to 30% by weight, and still further preferably
from 6 to 30% by weight in terms of an X-ray peak intensity ratio
of iron. When the amount of FeO (wustite) exceeds 50% by weight,
though the exothermic rising properties are good, the duration of
heat generation becomes short. On the other hand, when it is less
than 2% by weight, the exothermic rising properties become
dull.
[0265] The thickness of the oxygen-containing film of a prescribed
amount or the oxygen-containing film of iron powder containing
wustite and the amount of wustite are applied to the heat
generating composition or the heat generating composition molded
body at the time of lamination.
[0266] An iron powder containing a carbon component and/or covered
by a carbon component is also preferable. Although a proportion of
the carbon component is not limited so far as a ratio of the iron
component to the carbon component is 50% by weight or more, an iron
powder in which the surface thereof is partially covered by from
0.3 to 3.0% by weight of a conductive carbonaceous substance is
useful. Examples of the conductive carbonaceous substance include
carbon black, active carbon, carbon nanotubes, carbon nanohorns,
and fullerenes. Ones which have become conductive by doping are
also employable. Examples of the iron powder include reduced iron
powders, atomized iron powders, and sponge iron powders. In
particular, the case where the conductive carbonaceous substance is
active carbon and the iron powder is a reduced iron powder is
useful as a heat generating body.
[0267] Furthermore, in order to efficiently carry out covering by a
conductive carbonaceous substance, an oil such as a spindle oil may
be added in an amount of from 0.01 to 0.05% by weight to such an
extent that the fluidity of the iron powder is not hindered.
[0268] In the case of measuring the water mobility value of the
heat generating composition in the heat generating body and the
thickness and amount of wustite of the iron oxide film of iron
powder in the mixture or the heat generating composition in the
heat generating body, the heat generating composition or mixture
may be measured according to the following items.
1) Water Mobility Value:
[0269] The heat generating composition is taken out from the heat
generating body and measured according to the foregoing method of
measuring a water mobility value.
2) Thickness and Amount of Wustite of Iron Oxide Film of Iron
Powder:
[0270] A measuring sample as prepared by dispersing the heat
generating composition, the heat generating composition molded
body, the heat generating composition compression molded body or
the mixture in nitrogen-purged ion-exchanged water in a nitrogen
atmosphere, separating the iron powder using a magnet and drying
the iron powder in a nitrogen atmosphere is used.
[0271] The heat generating composition of the invention contains,
as essential components, an iron powder, a carbon component, a
reaction accelerator and water, and its production process is one
which can be put into practical use on an industrial scale. A
reaction mixture containing, as essential components, an iron
powder, a reaction accelerator and water and having a water content
of from 1 to 20% by weight and a water mobility value showing a
surplus water content of less than 0.01 is brought into contact
with an oxidizing gas under circumstances at 0.degree. C. or
higher, a temperature rise of the reaction mixture is regulated at
1.degree. C. or more within 10 minutes to produce a heat generating
mixture, and the subject heat generating mixture is used as a raw
material to form a heat generating composition. Alternatively, a
heat generating composition may be formed by subsequently further
adjusting the water content, or by further adding a carbon
component, etc. and adjusting the water content.
[0272] In the invention, it has become possible to realize the
contact treatment with an oxidizing gas within a short period of
time by regulating the water content of the reaction mixture at a
fixed amount or less, especially regulating the surplus water
content of the reaction mixture at a fixed amount or less and
carrying out an oxidizing contact treatment. By specifying the
surplus water content and performing the treatment within a short
period of time, adverse influences such as poor initial exothermic
rising of the heat generating composition and shortening of the
heat generation-retaining time can be avoided. Thus, it has become
possible to establish an industrial mass-production process.
Furthermore, although stirring or the like may not be achieved
during the contact treatment with an oxidizing gas, when stirring
or the like is achieved, the contact treatment with an oxidizing
gas can be surely carried out.
[0273] Here, so far as the iron powder is partially oxidized, the
state of the reaction mixture or heat generating mixture at the
time of the contact treatment with an oxidizing gas may be any of a
standing state, a transfer state, or a fluidizing state by
stirring, etc. and may be properly selected. Furthermore, the
circumstances at the time of mixing the respective components of
the reaction mixture, the heat generating mixture or the heat
generating composition and at the time of mixing at the time of
adjusting the water content are not limited, and examples thereof
include those in an oxidizing gas atmosphere and those in blowing
of an oxidizing gas.
[0274] The "adjustment of the water content" as referred to herein
means that after contact treating the heat generating mixture with
an oxidizing gas, water or an aqueous solution of a reaction
accelerator is added. Although the amount of addition of water or
an aqueous solution of a reaction accelerator is not limited,
examples thereof include the addition of a weight corresponding to
a reduced weight by the contact treatment and the addition of a
weight such that a desired water mobility value is obtained.
[0275] Whether or nor the adjustment of the water content is
introduced may be properly determined depending upon the
utility.
[0276] The heat generating composition of the invention contains,
as essential components, an iron powder, a carbon component, a
reaction accelerator and water and is started from a mixture
obtained by contact treating a reaction mixture containing, as
essential components, an iron powder, a reaction accelerator and
water with an oxidizing gas. The heat generating composition of the
invention is usually one obtained by adjusting the water content of
a heat generating mixture and is a heat generating composition
which is satisfactory in the exothermic rising, has a suitable
amount of surplus water and has excellent moldability. Furthermore,
it is possible to produce a heat generating body which can become
promptly warm at the time of use.
[0277] Accordingly, at least the iron powder further including the
carbon component has a history of oxidation by the contact
treatment with an oxidizing gas, and it is thought that this is
deeply related to excellent exothermic rising properties,
exothermic endurance and excellent moldability.
[0278] When the iron powder which is contact treated with an
oxidizing gas according to the invention is used, the amount of
addition of the carbon component (for example, active carbon) in
the heat generating composition can be reduced by, for example, 20%
or more. By reducing the amount of addition of the carbon
component, the costs are lowered.
[0279] According to the production process of the heat generating
mixture of the invention, it is possible to obtain a heat
generating composition having excellent exothermic rising
properties, excellent hydrophilicity, and excellent moldability. In
particular, a heat generating composition having remarkably
excellent moldability and exothermic characteristics together can
be obtained while specifying the water availability value at from
0.01 to 50, in particular 0.01 to 20.
[0280] The heat generating composition as produced by the
production process of the invention is remarkably improved with
respect to exothermic rising properties. Thus, the amount of
addition of the carbon component (such as active carbon) in the
heat generating composition can be reduced by, for example, 20% or
more so that it can contribute to a reduction in costs.
[0281] Furthermore, since the hydrophilicity is remarkably
improved, the moldability with a mold is remarkably improved. Thus,
since after molding, collapsed pieces of the heat generating
composition are not scattered on the surroundings of the heat
generating composition molded body, sealing can be appropriately
achieved so that a heat generating body free from sealing cut can
be produced. In this way, heat generating composition molded bodies
of various shapes can be produced, and heat generating bodies of
various shapes are formed.
[0282] Furthermore, in view of improving the exothermic rising
properties of the heat generating composition, the following are
preferable.
[0283] 1) A heat generating composition obtained by a contact
treatment (self heat generation) of a mixture of the essential
components of the heat generating composition, or a mixture of the
foregoing mixture and an acidic substance or other necessary
components with an oxidizing gas, a heat generating composition
obtained by additionally adjusting the water content of the
foregoing heat generating composition, or a heat generating
composition obtained by adding and mixing other components in the
foregoing heat generating composition.
[0284] 2) Any one of the following active iron powders having an
oxygen-containing film (for example, oxides) on at least a part of
the surface thereof is used as the iron powder: (a) an iron powder
having an oxygen-containing film of iron having a thickness, as
measured by the Auger electron spectroscopy, of 3 nm or more on the
surface thereof and (b) an iron powder having a content of wustite
of from 2 to 50% by weight in terms of an X-ray peak intensity
ratio to iron.
[0285] 3) A mixture of an active iron powder having an
oxygen-containing film (for example, oxides) on at least a part of
the surface thereof and an iron powder not having an
oxygen-containing film is used as the iron powder. In this case, a
mixture containing 60% by weight or more of an active iron powder
and less than 40% by weight of an iron powder other than the active
iron is preferable.
[0286] In the case of storing the heat generating composition which
is treated with an oxidizing gas or the heat generating composition
containing an active iron powder, or a material utilizing the same
over a long period of time, it is preferred to combine a hydrogen
formation inhibitor therewith. This is because in this way, a heat
generating body having excellent exothermic characteristics, which
is inhibited in the formation of hydrogen, is free from swelling of
the outer bag at the time of storage, etc. and has satisfactory
exothermic rising properties, is obtained.
[0287] Furthermore, so far as the rising characteristics are not
affected, the heat generating composition having a water mobility
value falling outside the range of from 0.01 to 20 can contain a
water-soluble polymer, a flocculant aid, a flocculent, an
agglomeration aid, a dry binding material, a dry binding agent, a
dry binder, an adhesive raw material, a tackifier, an excipient, a
flocculating agent, or a soluble sticky raw material.
[0288] Furthermore, since a marketed heat generating body in which
a heat generating composition is accommodated in an accommodating
bag is provided on the assumption that it is accommodated in an
outer bag which is an air-impermeable accommodating bag and is
storable over a long period of time, it is preferred to use a heat
generating composition containing a hydrogen formation inhibitor.
Since the heat generating composition which has passed through the
contact treatment with an oxidizing gas is an active composition,
it is important that the heat generating composition contains a
hydrogen formation inhibitor. Also, this efficacy is further
strengthened by using a pH adjusting agent together.
[0289] Furthermore, so far as the reaction characteristics and
exothermic characteristics are not affected, the heat generating
composition having a water mobility value of less than 0.01 may
contain a flocculant aid, a flocculent, an agglomeration aid, a dry
binder, a dry binding agent, a dry binding material, a sticky raw
material, a thickener, an excipient, or a water-soluble polymer in
an amount ranging from 0.01 to 3 parts by weight respectively.
[0290] The "flocculant aid" as referred to herein is a flocculant
aid as described in Japanese Patent No. 3,161,605 (JP-T-11-508314)
such as gelatin, natural gum, and corn syrup.
[0291] The "flocculant" as referred to herein is a flocculant as
described in JP-T-2002-514104 such as corn syrup and maltitol
syrup.
[0292] The "agglomeration aid" as referred to herein is an
agglomeration aid as described in JP-T-2001-507593 such as corn
syrup.
[0293] The "dry binder" as referred to herein is a dry binder as
described in JP-T-2002-514104 such as microcrystalline cellulose,
maltodextrin, and mixtures thereof.
[0294] The "dry binding agent" as referred to herein is a dry
binding agent as described in JP-T-2001-507593 such as maltodextrin
and sprayed lactose.
[0295] The "dry binding material" as referred to herein is a dry
binding material as described in JP-T-11-508314 such as
microcrystalline cellulose, maltodextrin, and mixtures thereof.
[0296] The "sticky raw material" or the "binder" as referred to
herein is a sticky raw material or binder as described in
JP-A-4-293989 such as water glass, polyvinyl alcohol (PVA), and
carboxymethyl cellulose (CMC).
[0297] The "thickener" as referred to herein is a thickener as
described in JP-A-6-343658 such as corn starch and potato
starch.
[0298] The "excipient" as referred to herein is an excipient as
described in JP-A-7-194641 such as .alpha.-starch and sodium
alginate.
[0299] As the "water-soluble polymer" as referred to herein, the
water-soluble polymer in the adhesive layer can be used.
[0300] The particle size of the water-insoluble solid component
constituting the moldable heat generating composition of the
invention is not limited so far as the heat generating composition
has moldability. In the case where any one of length, width and
height as the size of the heat generating composition molded body
as molded from the heat generating composition is small, the
moldability is improved by making the particle size small.
[0301] In addition, it is preferable in view of molding that the
particle size of the solid component constituting the moldable heat
generating composition is small. A maximum particle size of the
water-insoluble solid component exclusive of the reaction
accelerator and water in the components constituting the moldable
heat generating composition is preferably not more than 2.5 mm,
more preferably not more than 930 .mu.m, further preferably not
more than 500 .mu.m, still further preferably not more than 300
.mu.m, even further preferably not more than 250 .mu.m, and even
still further preferably not more than 200 .mu.m. Moreover, 80% or
more of the particle size of the solid component is usually not
more than 500 .mu.m, preferably not more than 300 .mu.m, more
preferably not more than 250 .mu.m, further preferably not more
than 200 .mu.m, still further preferably not more than 150 .mu.m,
and even further preferably not more than 100 .mu.m.
[0302] Incidentally, with respect to the particle size of the
water-insoluble solid component, separation is conducted using a
sieve, and the particle size of the component which has passed
through the sieve is calculated from an opening of the sieve. That
is, sieves of 8, 12, 20, 32, 42, 60, 80, 100, 115, 150, 200, 250
and 280 meshes and a receiving dish are combined in this order from
up to down. About 50 g of water-insoluble solid component particles
are placed on the uppermost 8-mesh sieve and shaken for one minute
using an automatic shaker. Weights of the water-insoluble solid
component particles on each of the sieves and the receiving dish
are weighed. The total amount thereof is defined as 100%, and the
particle size distribution is determined from weight fractions.
When the sum of all receiving dishes under the sieve of a specific
mesh size becomes 100% which is the total sum of the particle size
distribution, the size (.mu.m) calculated from the opening of the
specific mesh is defined as the particle size of the
water-insoluble solid component. Incidentally, each of the mesh
sieves may be combined with other mesh sieves. Here, the particles
which have passed through a 16-mesh sieve are defined to have a
particle size of not more than 1 mm; the particles which have
passed through a 20-mesh sieve are defined to have a particle size
of not more than 850 .mu.m; the particles which have passed through
a 48-mesh sieve are defined to have a particle size of not more
than 300 .mu.m; the particles which have passed through a 60-mesh
sieve are defined to have a particle size of not more than 250
.mu.m; the particles which have passed through a 65-mesh sieve are
defined to have a particle size of not more than 200 .mu.m; the
particles which have passed through an 80-mesh sieve are defined to
have a particle size of not more than 180 .mu.m; the particles
which have passed through a 100-mesh sieve are defined to have a
particle size of not more than 150 .mu.m; the particles which have
passed through a 115-mesh sieve are defined to have a particle size
of not more than 120 .mu.m; the particles which have passed through
a 150-mesh sieve are defined to have a particle size of not more
than 100 .mu.m; and the particles which have passed through a
250-mesh sieve are defined to have a particle size of not more 63
.mu.m, respectively. The same is applicable to mesh sizes of less
than these mesh sizes.
[0303] Furthermore, the heat generating composition can be
classified into a powder, a granulate heat generating composition
(having a water mobility value of less than 0.01), a moldable heat
generating composition (having a water mobility value of from 0.01
to 20), and a sherbet-like heat generating composition (having a
water mobility value exceeding 20 but not more than 50) depending
upon the state of adjustment of the water content or surplus water.
The heat generating composition as classified depending upon the
water mobility value is as described previously.
[0304] The "moldability" as referred to in the invention exhibits
that a laminate of the heat generating composition having a cavity
or concave die shape can be formed by force-through molding using a
trimming die having a cavity or cast molding using a concave die
and after molding including mold release, the molding shape of the
heat generating composition molded body is held. When the
moldability is revealed, since the shape is held until the heat
generating composition molded article is at least covered by a
covering material and a seal part is formed between the substrate
and the covering material, sealing can be achieved in the periphery
of the shape with a desired shape. Also, since so-called "spots"
which are a collapsed piece of the heat generating composition are
not scattered in the seal part, sealing can be achieved without
causing cutting in seal. The presence of the spots causes
insufficient sealing.
[0305] Next, with respect to the moldability, a measurement device,
a measurement method and a judgment method will be described
below.
1) Measurement Device:
[0306] With respect to the measurement device, a stainless
steel-made molding die (a plate having a size of 2 mm in
thickness.times.200 mm in length.times.200 mm in width and having a
cavity as treated by R5 in four corners of 60 mm in length.times.40
mm in width in a central part thereof) and a fixable leveling plate
are disposed above a travelable endless belt, and magnets (two
magnets having a size of 12.5 mm in thickness.times.24 mm in
length.times.24 mm in width are disposed in parallel) are disposed
under the endless belt. The magnets should cover a region of the
leveling plate and the vicinity thereof and a region larger than a
region covered by a cut side (40 mm) vertical to the advancing
direction of the cavity of the molding die.
2) Measurement Method:
[0307] With respect to the measurement method, a stainless steel
plate having a size of 1 mm in thickness.times.200 mm in
length.times.200 mm in width is placed on the endless belt of the
measurement device, a polyethylene film having a size of 70 .mu.m
in thickness.times.200 mm in length.times.200 mm in width is placed
thereon, and a stainless steel-made molding die is further placed
thereon. Thereafter, a leveling plate is fixed in a position of the
cavity of the molding die of 50 mm far from the end portion in the
advancing direction of the endless belt, 50 g of a heat generating
composition is then placed in the vicinity of the leveling plate
between the leveling plate and the cavity, and the heat generating
composition is filled in the cavity of the molding die while
leveling it by moving the endless belt at 1.8 m/min.
[0308] After the molding die has completely passed through the
leveling plate, the traveling of the endless belt is stopped. Next,
the molding die is removed, and a heat generating composition
molded body as laminated on the polyethylene film is observed.
3) Judgment Method:
[0309] With respect to the judgment method, in the surroundings of
the heat generating composition molded body, in the case where any
collapsed piece of the heat generating composition molded body
exceeding a maximum length of 800 .mu.m is not present and the
number of collapsed pieces of the heat generating composition
molded body having a maximum length of from 300 to 800 .mu.m is not
more than 5, it is to be noted that the heat generating composition
has moldability. The moldability is an essential property for a
heat generating composition to be used in the molding system. If
the heat generating composition does not have moldability, it is
impossible to produce a heat generating body by the molding
system.
[0310] The heat generating composition of the invention has
resistance to compression. The "resistance to compression" as
referred to herein means that a heat generating composition
compressed body obtained by compressing a heat generating
composition molded body as accommodated in a molding die within the
die to such an extent that the thickness is 70% of the die
thickness holds 80% or more of exothermic rising properties of the
exothermic rising properties of the heat generating composition
molded body before compression (a difference in temperature between
one minute and 3 minutes after starting a heat generation test of
the heat generating composition).
[0311] Here, the measurement method of exothermic rinsing
properties for the resistance to compression will be described
below.
1. Heat Generating Composition Molded Body:
[0312] 1) A magnet is provided in the vicinity of a central part of
the back side of a polyvinyl chloride-made supporting plate
[0313] (3 mm in thickness.times.600 mm in length.times.600 mm in
width) of a footed supporting table so as to cover a cavity shape
of a molding die.
[0314] 2) A temperature sensor is placed on the central part the
surface of the supporting plate.
[0315] 3) A polyethylene film (25 .mu.m in thickness.times.250 mm
in length.times.200 mm in width) as provided with an adhesive layer
having a thickness of about 80 .mu.m is stuck onto the supporting
plate via a sticky layer such that the center of the polyethylene
film is positioned at the sensor.
[0316] 4) On an underlay plate (280 mm in length.times.150 mm in
width.times.50 .mu.m to 2 mm in thickness), a polyethylene film
(230 mm in length.times.155 mm in width.times.25 .mu.m to 100 .mu.m
in thickness) is placed such that one end of the polyethylene film
is projected by about 20 mm outside the underlay plate and that one
end thereof in the length direction is substantially coincident
with one end of the underlay plate.
[0317] 5) A template (230 mm in length.times.120 mm in
width.times.3 mm in thickness) having a cavity (80 mm in
length.times.50 mm in width.times.3 mm in height) is placed on the
polyethylene film placed on the underlay plate; a template is
placed on the polyethylene film such that one end thereof in the
length direction is fitted to one end where the underlay plate and
the polyethylene film are coincident with each other and that in
the width direction, one end part of the width of the template is
placed at a position of the central part by about 20 mm far from an
opposing end to the side where the polyethylene film is projected
outward from the underlay plate. Next, the resulting assembly is
placed on the supporting plate together with the underlay
plate.
[0318] 6) A sample is placed in the vicinity of the cavity; a
force-in die plate is moved along the molding die; the sample is
charged into the cavity while stuffing; and the sample is leveled
while stuffing along the template plane (force-in die molding),
thereby filling the sample in the die.
[0319] 7) Next, the magnet beneath the supporting plate is removed;
the end portion of the projected polyethylene film is pressed; the
underlay plate is removed; and the temperature measurement is
started.
2. Heat Generating Composition Compressed Body:
[0320] 1) to 6) are the same as in the case of the heat generating
composition molded body.
[0321] 8) A die having a convex having a thickness of 0.9 mm which
can substantially tightly come into the cavity in relation of the
cavity with an unevenness is fitted to the cavity and compressed by
a roll press or plate press to prepare a heat generating
composition compressed body having a thickness of 2.1 mm
(compressed to 70% of the die thickness) within the die.
[0322] 9) The resulting assembly is placed on the supporting plate
together with the underlay plate; the magnet beneath the supporting
plate is removed; the end portion of the projected polyethylene
film is pressed; the underlay plate is removed; and the temperature
measurement is started.
[0323] With respect to the measurement of the exothermic
temperature, the temperature is measured for 5 minutes at a
measurement timing of 2 seconds using a data collector, and
resistance to compression is judged in terms of a difference in
temperature between after elapsing one minute and after elapsing 3
minutes.
[0324] The thickness after compression is preferably from 50 to
99.5%, more preferably from 60 to 99.5%, and further preferably
from 60 to 95% of the die thickness.
[0325] Incidentally, in the invention, it is to be noted that the
heat generating composition molded body includes a heat generating
composition compressed body.
[0326] The process for producing a heat cloth of the invention is a
process for producing a heat cloth by laminating a heat generating
composition molded body on a substrate by a molding system, further
covering a covering material thereon, and sealing the surroundings
of the heat generating composition molded body to provide a
sectional exothermic part constituted of the heat generating
composition molded body between packaging materials which
constitute an air-permeable accommodating bag, whereby two or more
plural sectional exothermic parts are disposed and fixed at
intervals and an exothermic part is formed of a gathering of the
sectional exothermic parts, which is characterized in that a
maximum width of the sectional exothermic parts is from 1 to 20 mm;
a maximum diameter (in the case where two or more axes are present
as in an ellipse, the maximum diameter means a shortest axis such
as a minor axis) is from 1 to 20 mm; a maximum height is from 0.1
to 20 mm; a space between the sectional exothermic parts is from 1
to 20 mm; the heat generating composition contains, as essential
components, an exothermic substance, a carbon component, a reaction
accelerator and water and has a water mobility value of from 0.01
to 20; 80% or more of water-insoluble solid components which
constitute the heat generating composition have a particle size of
not more than 300 m and a maximum particle size of not more than 1
mm; the packaging material is made of the substrate and the
covering material; at least one or a part of the substrate and the
covering material is permeable to air; and at least the
surroundings of the heat cloth are sealed. In addition, each of the
substrate and the covering material has a heat seal layer; an
adhesive layer made of an adhesive is provided on at least one of
the heat seal layers; in the substrate, the heat generating molded
body and the covering material, the substrate and the covering
material are temporarily adhered via the sticky layer in at least
the periphery of the heat generating composition molded body; and
after forming a temporary adhering seal part, the temporary
adhering seal part is heat sealed to form a heat seal part.
Furthermore, heat sealing is carried out in a width narrower than
that of the temporary adhering seal part, and thereafter, the heat
generating composition is moved into a region which is not heat
sealed within the temporary adhering seal part, thereby achieving
deadhesion. In this way, the heat generating composition molded
body becomes stable; real sealing by heat sealing becomes easy;
seal deviation or the like does not occur; a heat seal width with
fine lines can be embodied at high speed without causing sealing;
and it is possible to section an exothermic part without causing a
lowering of exothermic characteristics such as a decrease in
exothermic time due to sectioning of the exothermic part.
[0327] As a preferred production process of a heat cloth having
sectional exothermic parts in which an exothermic part thereof is
sectioned according to the molding system of the invention, any
molding method using a die may be employed. Examples thereof
include, a force-through molding method and a cast molding
method.
[0328] If desired, the heat generating composition or the heat
generating composition molded body may be subjected to in-die
compression or out-die compression. The "in-die compression" as
referred to herein means that the heat generating composition is
compressed by flexible rubber rolls or the like while the heat
generating composition is present within the die; and the "out-die
compression" as referred to herein means that after the heat
generating composition leaves from the die to become a heat
generating composition molded body, the heat generating composition
molded body is compressed by rolls or the like. Though this
compression is usually carried out after covering the heat
generating composition molded body by an underlay material and/or a
covering material, this may not be carried out.
[0329] The heat cloth of the invention is produced through the
accommodating step and the subsequent sealing step and cutting step
and so on. With respect to the sealing step and the cutting step
and so on, conventional methods and devices may be properly
selected and used.
[0330] Furthermore, in the seal step, the seal is not limited so
far as seal is possible. Usually, heat seal or compression seal or
a mixture thereof is employed. The surface of the seal part may be
of a plain shape or a patterned shape whose cross-sectional shape
is irregular, and a mixture of a plain shape and a patterned shape
whose cross-sectional shape is irregular. The mixture of pattern as
referred to herein means a mixture of a plain shape in the inside
of the seal part and a patterned shape in the outside of the seal
part, or a mixture of a patterned shape in the inside of the seal
part and a plain shape, a partially plain shape or a partially
patterned shape in the outside of the seal part. Furthermore, the
back side may be plain, with the front side being patterned, and
vice versa. Furthermore, a part or the whole of the pattern may be
a double pattern. Accordingly, following this, a plain or patterned
seal roll is used as a seal roll. Furthermore, a pair of seal rolls
may be used. Multiplex seal may be carried out by placing plural
seal rolls of two or more. Examples of the multiplex seal include
duplex seal, triplet seal, quadruplet seal, and quintuplet seal.
The width of seal may be the same or different and may be properly
determined. In the case of high-speed seal, a higher number of
multiplex seal is preferable. In the case of using a seal roll or a
compression seal roll to which the temperature is applied, the
temperature of a pair of rolls may be the same, or the temperature
of one roll may be different from that of the other roll.
[0331] The "force-through die molding" as referred to herein means
a continuous formation method in which by using a molding machine
for using a molding die and laminating a heat generating
composition molded body having a shape of the molding die on a
longitudinal substrate and a rotary sealer capable of covering the
laminate by a longitudinal covering material and sealing (for
example, heat seal, compression seal, and heat compression seal) a
desired sectioned part and the substrate together with the
surroundings of the covering material, the surroundings of the heat
generating composition molded body and a necessary place of the
sectioned part are heat sealed, thereby achieving a sealing
treatment.
[0332] Furthermore, a magnet may be used for molding the heat
generating composition of the invention. By using a magnet, it
becomes possible to easily achieve accommodation of the heat
generating composition in a mold and separation of the molded body
from the mold, thereby making it easier to mold a heat generating
composition molded body.
[0333] The "cast molding method" as referred to herein means a
molding method for laminating a heat generating composition molded
body on a longitudinal substance by filling in a casting mold
having a concave and transferring into a substrate. In the
continuous case, there is enumerated a continuous formation method
in which by using a molding machine for laminating a heat
generating molding molded body on a longitudinal substrate by
filling in a concave and transferring into a substrate by a
drum-type rotary body and a rotary sealer capable of covering the
laminate by a longitudinal covering material and sealing (for
example, heat seal, compression seal, and heat compression seal) a
desired sectioned part and the substrate together with the
surroundings of the covering material, the surroundings of the heat
generating composition molded body and a necessary place of the
sectioned part are heat sealed, thereby achieving a sealing
treatment.
[0334] Incidentally, the heat cloth may be produced by providing an
air-permeable adhesive layer at least between the heat generating
composition molded body and the covering material or providing an
underlay material such as non-woven fabrics between the heat
generating composition molded body and the covering material. In
the case of providing an air-permeable adhesive layer at least
between the heat generating composition molded body and the
covering material, there is no limitation so far as an
air-permeable adhesive layer is present at least between the heat
generating composition molded body and the covering material. For
example, the air-permeable adhesive layer may be provided on the
surface of the covering material opposing to the heat generating
composition molded body; and the air-permeable adhesive layer may
be provided on the heat generating composition molded body or a
laminate of the heat generating composition molded body and the
substrate and temporarily adhered under pressure or the like
between the covering material and the heat generating composition
molded body and/or the substrate.
[0335] Furthermore, it becomes possible to realize a high-speed
production process of a heat cloth by temporarily adhering the
substrate and between the heat generating composition molded body
as laminated on the substrate and the covering material by an
adhesive layer and then heat sealing the periphery of the heat
generating composition molded body and a circumferential seal part
which is the surrounding part of the heat cloth.
[0336] The heat cloth as produced by the foregoing production
process can produce a flexible heat cloth having a low bending
resistance and a heat cloth having high flexibility and strong
nerve such that the bending resistance is low in one direction and
high in the other direction.
[0337] The "water mobility value" as referred to herein is a value
showing an amount of surplus water which can transfer to the
outside of the heat generating composition in water present in the
heat generating composition. This water mobility value will be
described below with reference to FIGS. 16 to 20.
[0338] As shown in FIG. 16, a filter paper 17 of No. 2 (second
class of JIS P3801) in which eight lines are drawn radiating from
the central point with an interval of 45.degree. is placed on a
stainless steel plate 21 as shown in FIGS. 17 and 18; a template 18
having a size of 150 mm in length.times.100 mm in width and having
a hollow cylindrical hole 19 having a size of 20 mm in inner
diameter.times.8 mm in height is placed in the center of the filter
paper 17; a sample 20 is placed in the vicinity of the hollow
cylindrical hole 19; and a stuffer plate 14 is moved on and along
the template 18 and inserted into the hollow cylindrical hole 19
while stuffing the sample 20, thereby leveling the sample (force-in
die molding).
[0339] Next, as shown in FIG. 19, a non-water absorptive 70
.mu.m-thick polyethylene film 16A is placed so as to cover the hole
19, and a flat plate 16 made of stainless steel having a size of 5
mm in thickness.times.150 mm in length.times.150 mm in width is
further placed thereon and held for 5 minutes such that an
exothermic reaction is not caused.
[0340] Thereafter, a shown in FIG. 20, the filter paper 17 is taken
out, and an oozed-out locus of the water or aqueous solution is
read as a distance 22 (unit: mm) from a periphery 23 as an edge of
the hollow cylindrical hole to an oozed-out tip along the radiating
lines. Similarly, a distance 22 from each of the lines is read, and
eight values in total are obtained. Each of the eight values (a, b,
c, d, e, f, g and h) which are read out is defined as a measured
water content value. An arithmetic average value of the eight
measured water content values is defined as a water content value
(mm) of the sample.
[0341] Furthermore, the water content for the purpose of measuring
a real water content value is defined as a compounded water content
of the heat generating composition corresponding to the weight of
the heat generating composition having a size of 20 mm in inner
diameter.times.8 mm in height or the like, similar measurement is
conducted only with water corresponding to that water content, and
a value as calculated in the same manner is defined as a real water
content value (mm). A value obtained by dividing the water content
value by the real water content value and then multiplying with 100
is a water mobility value.
[0342] That is, the water mobility value is represented by the
following expression.
(Water mobility value)={[Water content value (mm)]/[(Real water
content value (mm))].times.100
[0343] With respect to the same sample, five points are measured,
and the five water mobility values are averaged, thereby defining
an average value thereof as a water mobility value of the
sample.
[0344] Furthermore, in the case of measuring the water mobility
value of the heat generating composition in the heat generating
body, with respect to the water content for measuring a real water
content, a percentage of water content of the heat generating
composition is calculated through measurement of the water content
of the heat generating composition by an infrared moisture meter, a
water content necessary for the measurement is calculated on the
basis of the percentage of water content, and a real water content
value is measured and calculated from the foregoing water
content.
[0345] In the invention, a heat generating body can be formed only
by laminating a heat generating composition molded body obtained by
molding a heat generating composition having surplus water with a
water mobility value of from 0.01 to 20 on a substrate, covering a
covering material thereon, and sealing at least the periphery of
the heat generating composition molded body. After accommodating it
in a packaging material such as a substrate and a covering
material, it is not necessary to add water. Accordingly, since the
process is remarkably simplified, the invention is superior in view
of the costs.
[0346] In the invention, the water mobility value (0 to 100) is
preferably from 0.01 to 20, more preferably from 0.01 to 18,
further preferably from 0.01 to 15, still further preferably from
0.01 to 13, even further preferably from 1 to 13, and even still
further preferably from 3 to 13.
[0347] In a heat generating body using a heat generating
composition molded body obtained by molding a moldable heat
generating composition containing surplus water as a connecting
substance according to the invention, the heat generating
composition contains an appropriate amount of surplus water
expressed by a water mobility value of from 0.01 to 20 as the
connecting substance without using a flocculant aid, a dry binding
agent, a flocculating agent, etc.
[0348] It is assumed that when the amount of surplus water in the
heat generating composition is appropriate, the surplus water
causes hydration against hydrophilic groups in the components of
the composition due to a bipolar mutual action or hydrogen bond,
etc. and that it is present even in the surroundings of hydrophobic
groups while having high structural properties. Thus, it is assumed
that the heat generating composition becomes in a state of a mud
ball, thereby revealing moldability. This is connecting water as a
connecting substance in some meaning. Besides, there is water in a
state called as free water which can freely move, and it is thought
that when the surplus water increases, the structure is softened,
whereby the free water increases. Furthermore, controlling factors
which an iron powder causes an oxidation reaction are an amount of
existing water and a feed amount of oxygen to the surface of the
iron powder. It is said that in a degree of water adsorbing film
(less than 100 angstroms), the water is not sufficient and that the
oxidation rate is small. When the adsorbing film becomes about 1
.mu.m, the water content becomes sufficient. Furthermore, since the
thickness of the water film is thin, feed of oxygen onto the
surface of the iron powder becomes easy, whereby the oxidation rate
becomes large. It is assumed that when the film becomes thicker to
an extent that the adsorbing film exceeds 1 .mu.m, the feed amount
of oxygen is reduced. The present inventors have obtained knowledge
that the water mobility value expressing the optimal water content
at which moldability and oxidation rate in fixed levels or more are
revealed is from 0.01 to 20, leading to accomplishment of the
invention.
[0349] That is, by using an appropriate amount of surplus water,
the respective component particles are coupled with each other by a
surface tension of water, moldability is generated in the heat
generating composition, and the water does not substantially
function as a barrier layer. Thus, the heat generating composition
comes into contact with air to generate heat. In addition, by using
a heat generating composition using an active iron powder or an
active heat generating composition using an active iron powder, the
heat generating composition becomes a heat generating composition
having remarkably excellent exothermic rising properties and high
moldability. Furthermore, heat generation occurs without causing
transfer of the water in the heat generating composition molded
body as produced by a molding and laminating system into a
packaging material or water absorptive sheet. In addition, by
providing plural sectional exothermic parts of the heat generating
composition molded body as sectioned by seal parts, it is possible
to provide a heat generating body which has flexibility itself, is
excellent in installation in places where flexibility is required,
such as various places of a human body and curved bodies, and is
excellent in feeling for use.
[0350] Furthermore, in the substrate, the covering material and the
heat generating composition molded body, by temporarily adhering at
least the covering material and the heat generating composition
molded body to each other via a sticky layer and then heat sealing
the periphery of the heat generating composition molded body and
the surroundings of the heat generating body, certainty of heat
seal is improved so that it becomes possible to design to make the
production speed of a heat generating body high and make the heat
seal width small.
[0351] The "moldability" as referred to in the invention exhibits
that a molded body of the heat generating composition having a
cavity or concave die shape is formed by force-through molding
using a trimming die having a cavity or cast molding using a
concave die, whereby after molding including mold release, the
molding shape of the heat generating composition molded body is
held.
[0352] When the moldability is revealed, since the shape is held
until the heat generating composition molded article is at least
covered by a covering material and a seal part is formed between
the substrate and the covering material, sealing can be achieved in
the periphery of the shape with a desired shape. Also, since
so-called "spots" which are a collapsed piece of the heat
generating composition are not scattered in the seal part, the
sealing can be achieved without causing cutting in seal. The
presence of the spots causes insufficient sealing.
1) Measurement Device:
[0353] With respect to the measurement device, a stainless
steel-made molding die (a plate having a size of 2 mm in
thickness.times.200 mm in length.times.200 mm in width and having a
cavity as treated by R5 in four corners of 60 mm in length.times.40
mm in width in a central part thereof) and a fixable leveling plate
are disposed above a travelable endless belt, and magnets (two
magnets having a size of 12.5 mm in thickness.times.24 mm in
length.times.24 mm in width are disposed in parallel) are disposed
under the endless belt.
[0354] The magnets should cover a region of the leveling plate and
the vicinity thereof and a region larger than a region covered by a
cut side (40 mm) vertical to the advancing direction of the cavity
of the molding die.
2) Measurement Method:
[0355] With respect to the measurement method, a stainless steel
plate having a size of 1 mm in thickness.times.200 mm in
length.times.200 mm in width is placed on the endless belt of the
measurement device, a polyethylene film having a size of 70 .mu.m
in thickness.times.200 mm in length.times.200 mm in width is placed
thereon, and a stainless steel-made molding die is further placed
thereon.
[0356] Thereafter, a leveling plate is fixed in a position of the
cavity of the molding die of 50 mm far from the end portion in the
advancing direction of the endless belt, 50 g of a heat generating
composition is then placed in the vicinity of the leveling plate
between the leveling plate and the cavity, and the heat generating
composition is filled in the cavity of the molding die while
leveling it by moving the endless belt at 1.8 m/min. After the
molding die has completely passed through the leveling plate, the
traveling of the endless belt is stopped. Next, the molding die is
removed, and a heat generating composition molded body as laminated
on the polyethylene film is observed.
3) Judgment Method:
[0357] With respect to the judgment method, in the surroundings of
the heat generating composition molded body, in the case where any
collapsed piece of the heat generating composition molded body
exceeding a maximum length of 800 .mu.m is not present and the
number of collapsed pieces of the heat generating composition
molded body having a maximum length of from 300 to 800 .mu.m is not
more than 5, it is to be noted that the heat generating composition
has moldability.
[0358] The moldability is an essential property for a heat
generating composition to be used in the molding system. If the
heat generating composition does not have moldability, it is
impossible to produce a heat generating body by the molding
system.
[0359] The "perforation" as referred to in the invention includes
one which is intermittently cut for the purpose of improving
flexural properties of the sectioned part and one which is
intermittently cut such that cutting by hand is possible. Its
degree, length and aperture are not limited but are determined
depending upon the desire. The perforation may be provided in all
sectioned parts or may be partially provided. The shape is not
particularly limited, and examples thereof include a circle, an
ellipse, a rectangle, a square, and a cut line (linear shape). For
example, in the perforation which is intermittently cut such that
cutting by hand is possible, a circular hole having an aperture of
from .phi.10 to 1, 200 .mu.m can be enumerated. The aperture of the
hole is more preferably from .phi.20 to 500 .mu.m.
[0360] It is preferable that the holes are positioned lined up in
the length and width. Furthermore, a shortest space between outer
peripheries of the adjacent holes in the length and width is not
limited so far as it is satisfactory with flexural properties and
possibility of cutting by hand. The shortest space is preferably
from 10 to 2,000 .mu.m, more preferably from 10 to 1,500 .mu.m,
further preferably from 20 to 1,000 .mu.m, still further preferably
from 20 to 500 .mu.m, and even further preferably from 20 to 200
.mu.m. The cutting properties by hand are remarkably improved by a
balance between the aperture of the hole and the shortest space of
outer peripheries of the adjacent holes in the length and
width.
[0361] The hole may be a cut line, and its length may be a length
corresponding to the aperture or may be larger than the aperture. A
shortest space between ends of the adjacent cut lines in the length
and width is corresponding to the shortest space between outer
peripheries of the adjacent holes.
[0362] For example, an aperture of the hole of from .phi.10 to
2,000 .mu.m is corresponding to a length of from 10 to 2,000 .mu.m,
and a shortest space between outer peripheries of the adjacent
holes in the length and width of from 10 to 2,000 .mu.m is
corresponding to a shortest space between ends of the adjacent cut
lines in the length and width of from 10 to 2,000 .mu.m. In the
case of a cut line, since it becomes long in one direction, its
length can be prolonged and may be from 10 to 50,000 .mu.m. A
shortest distance between the adjacent cut lines in the length and
width may be from 1 to 5,000 .mu.m.
[0363] The "bending resistance" as referred to in the invention
exhibits rigidity (tension or nerve) or flexibility and follows the
A method according to JIS L1096 (45.degree. cantilever method),
except for using a heat generating body itself as a sample. That
is, a heat generating body is placed on a horizontal table having a
smooth surface and having a slope at an angle of 45.degree. in one
end thereof such that one side thereof coincides with a scale base
line. Next, the heat generating body is slowly slid toward the
slope by an appropriate method, and when a central point of the one
end of the heat generating body comes into contact with the slope
A, the position of the other end is read by a scale. The bending
resistance is exhibited by a length (mm) for which the heat
generating body moves. Respective five sheets of heat generating
body are measured, and the bending resistance (calculated down to
the integral place) is expressed by an average value of lengths
measured in the length direction and the width direction, or in one
direction and the orthogonal direction thereto. However, in the
measurement, in the case of measuring an adhesive layer-provided
heat generating body such that the adhesive side is faced at the
horizontal table side, while the adhesive side provided with a
separator is faced at the horizontal table side. In any way, a
measured value in the side at which a minimum bending resistance is
measured is employed.
[0364] Furthermore, in the measurement, the following must be taken
into consideration.
[0365] (1) A heat generating composition-incorporated exothermic
part of the heat generating body is to retain on the horizontal
table to an extent of 5 mm or more in width.times.20 mm or more in
length. However, the length is to cross a region where the heat
generating composition is present or to cross linearly a region
where the heat generating composition is present and a region where
the heat generating composition is not present.
[0366] (2) In the case of an adhesive layer-provided heat
generating body, a plastic film having a bending resistance of not
more than 30 mm, or a limp and soft film such as a limp film having
a thickness of not more than 50 .mu.m, and preferably not more than
25 .mu.m and a plastic film in which wrinkles are formed by lightly
crumpling is to be used as a separator of the adhesive layer and
provided along the adhesive layer. Furthermore, with respect to the
bending resistance of the substrate and/or the covering material, a
specimen of 100 mm.times.200 mm is prepared, and a bending
resistance in the 200 mm direction is employed.
[0367] In the invention, the bending resistance in at least one
direction is usually not more than 100 mm, preferably not more than
80 mm, more preferably not more than 50 mm, further preferably not
more than 30 mm, and still further preferably not more than 20
mm.
[0368] A rate of bending resistance of the heat generating body or
exothermic part in the invention is a rate of bending resistance to
the full length of the heat generating body or exothermic part in
one direction and is calculated according to the following
expression.
(Rate of bending resistance)=(A/B).times.100
[0369] Wherein A represents a bending resistance of the heat
generating body or exothermic part in one direction; and B
represents the full length of the heat generating body or
exothermic part in the foregoing one direction.
[0370] In the invention, a rate of bending resistance in at least
one direction is usually not more than 50, preferably not more than
40, and more preferably not more than 30.
[0371] A ratio of bending resistance in the invention is a ratio of
a bending resistance in one direction to a smaller bending
resistance in bending resistances in the directions orthogonal
thereto in the plane orthogonal to the thickness direction of the
heat generating body or exothermic part. The ratio of bending
resistance is preferably 2 or more.
[0372] In the invention, in the case of a heat generating body
having sectional exothermic parts provided at intervals in the
striped form, a heat generating body provided with sectional
exothermic parts of a parallelepiped shape at intervals in the
striped form in which a maximum absolute value of a difference
between bending resistances in the two directions as intersecting
directions, a heat generating body further provided with an
adhesive layer, and a heat generating body provided with adhesive
layers at intervals in the striped form are very flexible in one
direction and rigid in one direction. Thus, these heat generating
bodies relieve symptoms such as stiff shoulders, lower-back pain,
and muscular fatigue and especially exhibit efficacy for relieving
a symptom of menstrual pain. In addition, these heat generating
bodies are able to be wound in a size substantially equal to the
width dimension in the width direction of the heat generating body,
become compact and are convenient for accommodation. Furthermore,
in the case of a separator-provided heat generating body, by using
a separator having a low bending resistance, winding is
possible.
[0373] Furthermore, in the case of providing a heat generating body
along the body, the body includes many two-dimensional curves, and
in shoulders, legs, abdomen, waist, arms, and the like, one
direction is substantially linear, and the other two directions are
formed of a substantially curved surface. Accordingly, since the
heat generating body of the invention which is able to form a
substantially linear surface in one direction and a curved surface
in the other two directions is able to form a two-dimensional
curved surface, it is able to well follow the body and is optimum
for warming of the body and relaxation or treatment of various
symptoms.
[0374] Furthermore, in the heat generating body of the invention,
by adjusting the size or space of the convex sectional exothermic
part, an exothermic part which is flexible and exhibits a uniform
temperature distribution or an exothermic part exhibiting a
pattern-like temperature distribution is obtainable. By the
pattern-like temperature distribution, it is possible to improve a
meridian effect of the warming part.
[0375] In the heat cloth having sectional exothermic parts as
provided at intervals in the striped form, a minimum bending
resistance on the surface orthogonal to the thickness direction
thereof is preferably not more than 50 mm, more preferably not more
than 40 mm, further preferably not more than 30 mm, and still
further preferably from 5 to 30 mm.
[0376] Such bending resistance and bending resistance ratio are
kept at least between 20 and 60.degree. C.
[0377] The "water retention" as referred to herein is a value as
measured and calculated in the following method. That is, about 1 g
of a sample fiber as prepared by cutting into a length of about 5
cm and well opening is dipped in pure water, and after elapsing 20
minutes (at 20.degree. C.), water among the fibers is removed using
a centrifuge by revolution at 2,000 rpm. A weight (W1) of the thus
prepared sample is measured. Next, the sample is dried in a vacuum
dryer at 80.degree. C. until it becomes constant in weight, thereby
measuring a weight (W2). A water retention is calculated according
to the following expression.
[Water retention (%)]=[(W1-W2)/W2].times.100
[0378] In the invention, the water retention is preferably 20% or
more.
[0379] The term "substantially planar" as referred to in the
invention means a planar surface not having an accommodating
concave such as an accommodating pocket, an accommodating section,
and an accommodating zone as provided in advance for the purpose of
accommodating the heat generating composition. Accordingly,
irregularities which do not intentionally accommodate the heat
generating composition may be present.
[0380] The "pocket" as referred to in the invention is an
accommodating pocket which is provided in advance for the purpose
of accommodating the heat generating composition and is a pocket as
described in JP-T-2001-507593. Since irregularities which are not
used for intentionally accommodating the heat generating
composition molded body are not the pocket, even when such
irregularities are present on a substrate, it is to be noted that
such a substrate is defined as a substantially planar
substrate.
[0381] The "accommodating section" as referred to herein is an
accommodating section for accommodation as provided in advance on
the packaging material for the purpose of accommodating the heat
generating composition and is an accommodating section as described
in Japanese Patent No. 3,161,605 and JP-T-11-508314. Since
irregularities which are not used for intentionally accommodating
the heat generating composition molded body are not the
accommodating section, even when such irregularities are present on
a substrate, it is to be noted that such a substrate is defined as
a substantially planar substrate.
[0382] The "accommodating zone" as referred to herein is an
accommodating zone for accommodation as provided in advance on the
packaging material for the purpose of accommodating the heat
generating composition and is an accommodating zone as described in
Japanese Patent No. 3,161,605 and JP-T-11-508314. Since
irregularities which are not used for intentionally accommodating
the heat generating composition molded body are not the
accommodating zone, even when such irregularities are present on a
substrate, it is to be noted that such a substrate is defined as a
substantially planar substrate.
[0383] The heat generating body of the invention is able to give
various shapes, thicknesses and temperature zones and therefore,
can be used for various utilities such as use for a joint, facial
esthetic use, use for eyes, slimming use, use for heating or
warming a dripping solution, use for a wet compress pack, use for a
medical body warmer, use for a neck, use for a waist, use for a
mask, use for a glove, use for hemorrhage, use for relaxation of
symptoms such as shoulder pain, muscular pain, and menstrual pain,
use for a cushion, use for heating or warming a human body during
the operation, use for a thermal sheet, use for thermally
volatilizing an aroma, use for an abdomen, insecticidal use by
thermal volatilization, and use for treating cancer in addition to
common warming of a human body. In addition, the heat generating
body of the invention can be used for heating or warming machines,
pets, etc.
[0384] For example, in the case of using for relaxation of
symptoms, the heat generating body of the invention is applied
directly in a necessary site of the body or indirectly via a cloth,
etc. Furthermore, in the case of using for heating or warming a
human body during the operation, a method for using the heat
generating body of the invention includes the following
methods.
[0385] (1) The heat generating body is directly applied to a body
requiring heating or warming.
[0386] (2) The heat generating body is fixed on a covering, etc.
and covered on the body.
[0387] (3) The heat generating body is fixed on a cushion to be
placed beneath the body, etc.
[0388] (4) The heat generating body is used as a covering or a
cushion which is a product having the heat generating body provided
therein in advance.
[0389] Incidentally, examples of the pain of muscles or bones
include acute muscle pain, acute bone pain, acute reference pain,
previous muscle pain, previous bone pain, chronic reference pain,
and join pain of knee, elbow, etc.
[0390] The holding time is not limited but is preferably from 20
seconds to 24 hours, more preferably from one hour to 24 hours, and
further preferably from 8 hours to 24 hours. The holding
temperature is preferably from 30 to 50.degree. C., more preferably
from 32 to 50.degree. C., further preferably from 32 to 43.degree.
C., still further preferably from 32 to 41.degree. C., and even
further preferably from 32 to 39.degree. C.
[0391] The invention will be specifically described below with
reference to the Examples, but it should not be construed that the
invention is limited thereto.
BRIEF DESCRIPTION OF THE DRAWINGS
[0392] FIG. 1 is a plan view of an embodiment of the heat cloth of
the invention.
[0393] FIG. 2 is a cross-sectional view along the line Z-Z of the
same.
[0394] FIG. 3 is a cross-sectional view along the line Y-Y of the
same.
[0395] FIG. 4 is a cross-sectional view of other embodiment of the
heat cloth of the invention.
[0396] FIG. 5 is a plan view of other embodiment of the heat cloth
of the invention.
[0397] FIG. 6 is a plan view of other embodiment of the heat cloth
of the invention.
[0398] FIG. 7 is a plan view of other embodiment of the heat cloth
of the invention.
[0399] FIG. 8 is a plan view of other embodiment of the heat cloth
of the invention.
[0400] FIG. 9(a) is a plan view of other embodiment of the heat
cloth of the invention; FIG. 9(b) is a cross-sectional view along
the line X-X of the same; and FIG. 9(c) is a cross-sectional view
of other embodiment of the heat cloth of the invention.
[0401] FIG. 10 is a plan view of other embodiment of the heat cloth
of the invention (FIG. 10(a) shows a heat cloth of the end part,
and FIG. 10(b) shows a heat cloth of the central part).
[0402] FIG. 11 is a plan view of other embodiment of the heat cloth
of the invention.
[0403] FIG. 12 is a plan view of other embodiment of the heat cloth
of the invention.
[0404] FIG. 13 is a plan view of a modified example of the shape of
the heat cloth of the invention.
[0405] FIG. 14 is a schematic view of force-through molding of the
heat cloth of the invention using a leveling plate.
[0406] FIG. 15 is an explanatory view in the vicinity the leveling
plate of the same.
[0407] FIG. 16 is a plan view of a filter paper for the measurement
of water mobility value in the invention.
[0408] FIG. 17 is an oblique view for explaining the measurement of
water mobility value in the invention.
[0409] FIG. 18 is a cross-sectional view for explaining the
measurement of water mobility value in the invention.
[0410] FIG. 19 is a cross-sectional view for explaining the
measurement of water mobility value in the invention.
[0411] FIG. 20 is a plan view of a filter paper after carrying out
the measurement of water mobility value in the invention.
DESCRIPTION OF REFERENCE NUMERALS AND SIGNS
[0412] 1: Heat cloth [0413] 2: Sectional exothermic part [0414] 2B:
Heat generating composition molded body [0415] 3: Sectioned part
[0416] 3A: Circumferential seal part [0417] 4: Perforation [0418]
4A: Notch [0419] 5: Substrate [0420] 6: Covering material [0421] 7:
Adhesive layer [0422] 7A: Thermal buffer sheet [0423] 8: Band
[0424] 8A: Raw material which is stretchable in a direction
intersecting the longitudinal direction [0425] 8B: Space [0426] 9:
Fixing measure (for example, a hook and loop fastener) [0427] 10:
Separator [0428] 11: Die [0429] 11a: Die hole [0430] 12: Mold
[0431] 12a: Mold hole [0432] 13: Magnet [0433] 14: Pushing plate
[0434] 15: Leveling plate [0435] 16: Flat plate [0436] 16A:
Non-absorptive film (for example, a polyethylene film) [0437] 17:
Filter paper in which eight lines are drawn radiating from the
central point with an interval of 45.degree. [0438] 18: Die plate
having a hollow cylindrical hole [0439] 19: Hole [0440] 20: Sample
[0441] 21: Stainless steel plate [0442] 22: Distance to the
oozed-out locus of water or aqueous solution [0443] 23: Position
corresponding to a hollow cylindrical hole on filter paper
EXAMPLES
Example 1
[0444] A heat generating composition having a water mobility value
of 10, which is a mixture consisting of 100 parts by weight of a
reduced iron powder (particle size: not more than 300 .mu.m)), 7.0
parts by weight of active carbon (particle size: not more than 300
.mu.m), 5.0 parts by weight of a wood meal (particle size: not more
than 300 .mu.m), 0.8 parts by weight of a water absorptive polymer
(particle size: not more than 300 .mu.m), 0.2 parts by weight of
calcium hydroxide, 0.7 parts by weight of sodium sulfite and 11% of
salt water, was used.
[0445] Next, as shown in FIG. 1, FIG. 2(a) and FIG. 3, by using the
heat generating composition, heat generating composition molded
bodies 2B were provided on the surface of a polyethylene film 5B of
a substrate 5 made of the polyethylene film 5B provided with a 30
.mu.m-thick acrylic adhesive layer 7 provided with a separator 10
by force-through molding using a trimming die having eight cavities
of 5 mm in width.times.80 mm in length at intervals of 5 mm, so as
to form eight sectional exothermic parts 2; next, an air-permeable
covering material 6 made of a laminate of a nylon-made non-woven
fabric 6A with a basis weight of 40 g/m.sup.2 on a
polyethylene-made porous film 6B was covered thereon; and the
peripheries of the respective heat generating composition molded
bodies 2B and the circumferential part of a heat cloth 1 were
sealed.
[0446] A sectioned part 3 which is a seal part between the adjacent
heat generating composition molded bodies 2B was heat sealed in a
seal width of 3 mm. Furthermore, the circumferential part of the
heat cloth 1 was sealed in a seal width of 8 mm, thereby obtaining
a heat cloth 1 having an external dimension of 98 mm in
length.times.91 mm in width.
[0447] Incidentally, the air permeability of the air-permeable
covering material 6 was 400 g/m.sup.2/24 hr in terms of a moisture
permeability by the Lyssy method. With respect to the bending
resistance, the long side direction of the exothermic part
(direction orthogonal to the stripe direction) exhibited a minimum
bending resistance and was found to be 20 mm so that a feeling for
use was very excellent. Furthermore, this heat cloth 1 is able to
be wound, becomes compact and is convenient for accommodation. This
heat cloth 1 was sealed and accommodated in an air-impermeable
accommodating bag (hereinafter referred to as "outer bag") and
allowed to stand at room temperature for 24 hours. After 24 hours,
the heat cloth was taken out from the outer bag and then subjected
to an exothermic test of the body. As a result, it was felt warm
within 3 minutes, and the warmth was continued for 7 hours. At the
same time, curved surface fitness, winding properties and
usefulness were evaluated. As a result, the heat cloth was superior
in all of these evaluations.
[0448] Incidentally, FIG. 2(b) is a cross-sectional view of other
embodiment in which a thermal buffer sheet 7A is provided in the
central part of the adhesive layer.
[0449] FIG. 4 is an example of the substrate 5 in which a
polypropylene-made non-woven fabric 5A is laminated on a
polyethylene film 5B.
Comparative Example 1
[0450] Heat generating composition molded bodies were produced in
the same manner as in Example 1, except for setting the water
mobility value to not more than 0.01. A heat cloth was produced in
the same manner as in Example 1. However, collapsed pieces of the
heat generating composition molded body were scattered in the
peripheries of the heat generating composition molded bodies, and
cutting in seal was caused in the seal part. Furthermore, this heat
cloth was subjected to an exothermic test of the body. As a result,
the temperature excessively raised or the temperature was not
uniform so that it was no longer useful as a heat cloth.
Comparative Example 2
[0451] A circumferential part of a heat cloth was sealed in a seal
width of 8 mm in the same manner as in Example 1, except that
sealing between the adjacent heat generating composition molded
bodies 2B was not carried out, thereby obtaining a heat cloth
having the same shape as in Example 1 (91 mm in length.times.96 mm
in width) and having an external dimension of 134 mm in
length.times.96 mm in width. Furthermore, the practicality of the
heat cloth was evaluated in the same manner as in Example 1. As a
result, the heat cloth was deteriorated in all of curved surface
fitness, winding properties and usefulness.
Example 2
[0452] A batchwise stirring tank composed of a mixer equipped with
a rotary blade in a blade form of a ventilation fan was used as an
oxidizing gas contact treatment device, and air was used as an
oxidizing gas. First of all, a reaction mixture consisting of 100
parts by weight of a reduced iron powder (particle size: not more
than 300 .mu.m) and 5 parts by weight of 11% salt water and having
a water mobility value of not more than 0.01 was charged in the
contact treatment device vessel. Next, the upper portion of the
contact treatment device vessel was opened to air, and the reaction
mixture was subjected to self heat generation with stirring in the
opened state to air under circumstances at 20.degree. C. After
about 20 seconds, at a point of time when the temperature rise of
the reaction mixture reached 15.degree. C., the reaction mixture
was sealed in an air-impermeable accommodating bag and cooled to
room temperature, thereby obtaining a heat generating mixture. The
heat generating mixture had a wustite content of 10%. Next, the
contact treated reaction mixture was mixed with 5.3 parts by weight
of active carbon (particle size: not more than 300 .mu.m), 5 parts
by weight of a wood meal (particle size: not more than 300 .mu.m),
1.2 parts by weight of a water absorptive polymer (particle size:
not more than 300 .mu.m), 0.2 parts by weight of calcium hydroxide,
0.7 parts by weight of sodium sulfite and 11% of salt water,
thereby obtaining a heat generating composition having a water
mobility value of 5.
[0453] Next, the heat generating composition which had been molded
by a trimming die in which a space having a width of 10 mm was
provided in the central part thereof and eight (sixteen in total)
cavities having 5 mm in width.times.35 mm in length were
respectively provided at intervals of 5 mm while interposing the
space was laminated on a substrate.
[0454] As the substrate, an 80 .mu.m-thick heat seal layer-provided
polyethylene film was used; and as an air-permeable covering
material, an adhesive layer-provided air-permeable covering
material composed of an 80 .mu.m-thick heat seal layer-provided
polyethylene-made porous film and a covering material made of a
nylon non-woven fabric with a basis weight of 40 g/m.sup.2 having
an SIS based adhesive provided in a cobweb form by a melt blow
method in the porous film side was used.
[0455] Then, as shown in FIG. 5, an adhesive layer-provided heat
cloth 1 was prepared by providing an SIS based adhesive in a cobweb
form on the heat cloth 1 having a longest external dimension of 223
mm in length.times.95 mm in width by a melt blow method. This heat
cloth 1 has sectional exothermic parts 2 of 10 mm in width.times.45
mm in length.times.2 mm in height, a seal between the adjacent
sectional exothermic parts 2 is sealed in a width of 5 mm, and two
groups each composed of eight sectional exothermic parts 2 are
formed. The respective groups are provided while holding a space of
7 mm in width in the center.
[0456] After temporarily adhering the substrate, the heat
generating composition molded body and the covering material, the
peripheries of the heat generating composition molded bodies and
the surroundings of the heat cloth were heat sealed. The temporary
adhering part had a seal strength at 20.degree. C. of 200 g/25 mm.
Furthermore, the heat seal part as heat sealed after temporary
adhesion had a seal strength at 60.degree. C. of 1,500 g/25 mm. A
seal width of the sectional exothermic parts is 5 mm; and a seal
width of the surroundings of the heat cloth is 10 mm in the end
part in the width direction and 8 mm in other part. Incidentally,
the air permeability of the air-permeable covering material was 260
g/m.sup.2/24 hr in terms of a moisture permeability by the Lyssy
method. There was thus obtained a separator-provided heat cloth as
provided with an adhesive layer in which the surface of the
air-permeable covering material was made of a non-woven fabric and
the other surface which is impermeable to air was provided with an
SIS based adhesive in a cobweb form by a melt blow method. This
heat cloth was sealed and accommodated in an outer bag and allowed
to stand at room temperature for 24 hours. After 24 hours, the heat
cloth was taken out from the outer bag and then subjected to an
exothermic test of the body. As a result, it was felt warm within 3
minutes, and the warmth was continued for 7 hours. At the same
time, curved surface fitness, winding properties and usefulness
were evaluated. As a result, the heat cloth was superior in all of
these evaluations.
[0457] Incidentally, though the width between the foregoing
sectional exothermic parts 2 is equal, it is also possible to make
the width in the both end parts shortest by making the width
between the sectional exothermic parts 2 in the central part
longest.
Example 3
[0458] By using the same heat generating composition, substrate and
covering material as in Example 1, except for changing the reduced
iron powder of Example 1 to an iron powder (particle size: not more
than 300 .mu.m) containing 2% by weight of a carbon component
resulting from a coating treatment of sponge iron with active
carbon, heat generating composition molded bodies were molded by
force-through molding using a trimming die having twelve cavities
of 5 mm in width.times.80 mm in length at intervals of 7 mm,
laminated on the substrate and covered by the covering material;
the peripheries of the heat generating composition molded bodies 2B
were sealed in a seal width of 5 mm to form a sectioned part 3; the
periphery of a heat cloth 1 was sealed in a seal width of 8 mm; and
a perforation 4 which can be cut by hand was provided in the
sectioned part 3, thereby obtaining a heat cloth 1 provided with
the perforation 4 of 153 mm in length.times.98 mm in width having
twelve rectangular sectional exothermic parts 2 (see FIG. 6).
[0459] This heat cloth 1 was sealed and accommodated in an
air-impermeable outer bag and allowed to stand at room temperature
for 24 hours. After 24 hours, the heat cloth 1 was taken out from
the outer bag and then subjected to an exothermic test. As a
result, the temperature reached 34.degree. C. within 3 minutes, and
exothermic duration of 34.degree. C. or higher was long as 8 hours.
Furthermore, by drawing the heat cloth 1 right and left from the
end in the central part by fingers along the perforation 4, two
heat cloths each having six sectional exothermic parts could be
prepared. The results of the exothermic test were satisfactory
results, too. Furthermore, curved surface fitness, winding
properties and usefulness were evaluated by a test of the body of
the heat cloth 1. As a result, the heat cloth 1 was superior in all
of these evaluations before and after cutting the heat cloth 1 by
fingers.
Example 4
[0460] A heat cloth 1 the same as in Example 3 was prepared, which
is an example of a V-notch 4A for tearing provided in the both end
parts of the perforation (see FIG. 7).
Example 5
[0461] As a heat generating composition, a mixture consisting of
100 parts by weight of an iron powder (particle size: not more than
300 .mu.m) containing 15% by weight of FeO and 40 parts by weight
of 11% salt water (salt: 4.4 parts by weight, water: 35.6 parts by
weight) was charged in a frying pan and heated for mixing in air
until the water disappeared. Next, 5.3 parts by weight of active
carbon, 5 parts by weight of a 100 mesh-passed wood meal, 1.0 part
by weight of a water absorptive polymer, 0.2 parts by weight of
calcium hydroxide and 0.7 parts by weight of sodium sulfite were
added, and 35.6 parts by weight of water was further added,
followed by mixing to prepare a heat generating composition having
a water mobility value of 8. Next, by using heat generating
composition, a heat cloth 1 having an external dimension of 96
mm.times.77 mm was prepared in the same manner as in Example 1, in
which heat generating composition molded bodies 2 of 10 mm in
length.times.10 mm in width.times.2 mm in height were disposed 4
lines in length and 5 lines in width at intervals of 7 mm, a heat
seal width of the sectioned part was 5 mm, and a heat seal width of
the surroundings of the heat cloth was 8 mm.
[0462] This heat cloth 1 was sealed and accommodated in an outer
bag and allowed to stand at room temperature for 24 hours in the
same manner as in Example 1. After 24 hours, the heat cloth was
taken out from the outer bag and then subjected to an exothermic
test of the body. As a result, it was felt warm within 3 minutes,
and the warmth was continued for 8 hours. At the same time, curved
surface fitness, winding properties and usefulness were evaluated.
As a result, the heat cloth was superior in all of these
evaluations.
Example 6
[0463] A batchwise stirring tank composed of a mixer equipped with
a stirring blade was used as an oxidizing gas contact treatment
device, and air was used as an oxidizing gas. A reaction mixture
consisting of 100 parts by weight of a reduced iron powder
(particle size: not more than 300 .mu.m), 5.3 parts by weight of
active carbon (particle size: not more than 300 .mu.m), 5 parts by
weight of a wood meal (particle size: not more than 300 .mu.m), 0.8
parts by weight of a water absorptive polymer (particle size: not
more than 300 .mu.m), 0.2 parts by weight of calcium hydroxide
(particle size: not more than 300 .mu.m), 0.7 parts by weight of
sodium sulfite (particle size: not more than 300 .mu.m) and 5 parts
by weight of 11% salt water and having a water mobility value of
not more than 0.01 was charged in the device vessel. Next, in the
state that the upper portion of the device vessel adjusted at
20.degree. C. was opened to air, at a point of time when the
exothermic rise of the reaction mixture reached 40.degree. C., 11%
salt water was added to the reaction mixture with stirring to
adjust the water content, thereby obtaining a heat generating
composition having a water mobility value of 8.
[0464] Next, on a substrate having a separator-provided adhesive
layer as provided on a polyethylene film, heat generating
composition molded bodies 2B were laminated by force-through
molding such that pillar-like sectional exothermic parts 2 having a
diameter of 10 mm were disposed 4 lines in length and 5 lines in
width at intervals of 7 mm. Next, a covering material made of a
non-woven fabric-provided polyethylene-made porous film was placed
thereon such that the polyethylene film and the porous film were
faced at each other.
[0465] Then, the peripheries of the respective heat generating
composition molded bodies 2B were heat sealed to obtain a heat
cloth 1 having an exothermic part composed of twenty sectional
exothermic parts 2 as shown in FIG. 8. This heat cloth is a heat
cloth 1 of 96 mm in length.times.77 mm in width in which a heat
seal width of a sectioned part 3 is 5 mm and a heat seal width of
the surroundings of the heat cloth 1 is 8 mm.
Example 7
[0466] A heat cloth 1 the same as in Example 6 was prepared, except
for forming square sectional exothermic parts 2 in place of the
circular sectional exothermic parts 2 of Example 6.
[0467] As shown in FIG. 9(b), a spacial part 6D is present between
the adjacent sectional exothermic parts 2. Next, an air
permeability adjusting material 6C made of a polyethylene film of
96 in length.times.61 mm in width, on the entire surface of which
was provided an adhesive layer, was stuck onto the non-woven fabric
of the covering material 6 while leaving a the both ends of the
sectional exothermic part 2 in a width of 5 mm. A sectioned part 3
is a concave; the sectional exothermic part 2 is a convex; and the
sectional exothermic parts 2 become a support for the air
permeability adjusting material, thereby constituting the spacial
part 6D together with the sectioned part 3. This spacial part 6D
works as an air-permeable layer, and the periphery in the both end
parts of the sectioned part 3 works as an air intake.
[0468] This heat cloth 1 was sealed and accommodated in an
air-impermeable outer bag and allowed to stand at room temperature
for 24 hours. After 24 hours, the heat cloth was taken out from the
outer bag and then subjected to an exothermic test on a plate as
adjusted at 30.degree. C. As a result, the temperature reached
35.degree. C. within one minute, and the exothermic duration at 50
to 59.degree. C. was long as 10 hours. FIG. 9(c) shows an example
in which a part of the air permeability adjusting material 6C is
fixed to the sectioned part 2 via the sticky layer and each of the
sectional exothermic parts 2 has an independent spacial part
6C.
[0469] FIG. 9(a) is a plan view of an embodiment of the heat cloth
in which a region including the whole of plural sectional
exothermic parts 2 and the both end parts of the heat cloth 1 as
well as the surroundings of the sectional exothermic part 2 as
formed by sealing the surroundings of the heat generating
composition molded bodies 2 is covered by the air permeability
adjusting material 6C; the sectioned part 3 is a concave; the
sectional exothermic part 2 is a convex; the sectional exothermic
part 2 works as a support of the air permeability adjusting
material 6C; a spacial air-permeable layer is made of the spacial
part 6D which is constituted of the air permeability adjusting
material 6C and the sectioned part 3; and an air hole 16
constituted of the both end parts of the sectioned part 3, the
sectional exothermic part 2 and the air permeability adjusting
material 6C works as an air intake. FIG. 9(b) is a cross-sectional
view along the line X-X of FIG. 9(a); and FIG. 9(c) shows an
example in which the air permeability adjusting material 6C is
fixed in the substantially central part of the sectioned part 3 and
the spacial part 6D in FIG. 9(b) is divided into two parts by the
air permeability adjusting material 6C.
Example 8
[0470] A hydrophilic adhesive layer-provided heat cloth having the
same shape as in Example 6 was prepared in the same manner as in
Example 6, except for using a heat seal layer-provided laminate
(0.3 g/m.sup.2/day) made of a laminate of biaxially stretched
polypropylene and a silicon oxide-deposited polyester film as the
substrate and changing the adhesive to a hydrophilic adhesive. This
heat cloth was sealed and accommodated in an air-impermeable outer
bag and allowed to stand at room temperature for 24 hours. After 24
hours, the temperature was returned to room temperature, the heat
cloth was then taken out from the outer bag, and the separator was
removed, followed by subjecting to an exothermic test of the body.
As a result, it was felt warm within 3 minutes, and the moderate
warmth was continued for 8 hours or more. Furthermore, curved
surface fitness, curl properties and usefulness were evaluated. As
a result, the heat cloth was superior in all of these
evaluations.
[0471] Furthermore, this heat cloth was sealed and accommodated in
an air-impermeable outer bag and kept at 50.degree. C. for 10 days.
As a result, exothermic characteristics of the heat cloth did not
change before and after keeping.
[0472] Incidentally, the hydrophilic adhesive layer was prepared in
the following manner.
[0473] A component made of 4.5% by weight of polyacrylic acid, 1.5%
by weight of poly(sodium acrylate), 4.0% by weight of carboxymethyl
cellulose, 15.0% by weight of glycerin, 5.0% by weight of
polypropylene glycol, 0.1% by weight of aluminum hydroxide, 6.0% by
weight of kaolin and 62.85% by weight of water was charged in a
mixing machine and thoroughly stirred until the mixture became
pasty, thereby preparing a hydrophilic adhesive. This hydrophilic
adhesive was uniformly coated on a separator resulting from a
silicone treatment of polyethylene terephthalate (PET) having a
thickness of 40 .mu.m. This hydrophilic adhesive layer surface was
stuck onto the exposed surface of the substrate of the heat
cloth.
Example 9
[0474] By using the heat generating composition of Example 2, a
non-woven fabric resulting from embossing of a heat seal
layer-provided polyethylene film was laminated on the substrate,
and a napped (fluffy) non-woven fabric was further laminated
thereon. By using this laminate, a non-woven fabric with a basis
weight of 80 g/m.sup.2 was laminated on a heat seal layer-provided
perforated polyethylene film and used as a covering material. This
laminate had the same air permeability as in Example 2.
[0475] A heat cloth 1 having the shape as shown in FIG. 5 was
prepared in the same manner as in Example 2.
[0476] As a result of subjecting the heat cloth 1 to an exothermic
test, the same results as in Example 2 were obtained.
Example 10
[0477] FIG. 10 is a plan view to show one example of the heat cloth
of the invention. In the drawing, 2 indicates a heat cloth 1 in
which seven heat generating composition molded bodies 2B are
accommodated in a rectangular air-permeable bag of 5 mm in
thickness.times.100 mm in length.times.55 mm in width as formed in
a flat shape. As a non-woven fabric, an extensible and
air-permeable non-woven fabric was employed so as to have high
fixing properties and air permeability. This air-permeable
stretchable non-woven fabric-made band 8 is formed so as to impart
stretchability and air permeability by partially melting the
non-woven fabric on the both surfaces of a urethane based elastomer
film having fine pores formed therein in an extended state in the
longitudinal direction and then releasing. This band 8 could be
stretched twice into a size of 1 mm in thickness.times.250 mm in
length.times.60 mm in width and had good fixing properties and air
permeability. This band 8 had a weight of 6 g, a stress at the time
of 100% extension of 300 g/25 mm and a recovery rate at the time of
100% extension was 95%.
[0478] Then, the band 8 is constituted of a non-woven fabric having
a female fastener function of a hook and loop fastener on the both
surface thereof.
[0479] Furthermore, the heat cloth 1 is stuck via an adhesive
(acrylic adhesive) in a reed screen shape in a stripe form of 55 mm
in length.times.5 mm in width at intervals of 10 mm in the same
pattern as shown in FIG. 1.
[0480] The constitution of the heat cloth 1 will be described below
in detail. As the heat generating composition, the same material as
in Example 2 was used. Furthermore, as the air-permeable packaging
material, a laminate made of a 70 .mu.m-thick finely porous
polyethylene film on a nylon non-woven fabric with a basis weight
of 40 g/m.sup.2 and having a moisture permeability by the Lyssy
method of 700 g/m.sup.2/24 hr was used. As the air-impermeable
packaging material, a 50 .mu.m-thick polyethylene film was
used.
[0481] Seven heat generating composition molded bodies having a
length of 25 mm and a width of 5 mm were laminated at intervals of
6 mm on the substrate of the air-impermeable packaging material by
force-through molding. Next, the air-permeable packaging material
and the air-impermeable packaging material were overlaid and
laminated such that the polyethylene surface of the air-permeable
packaging material and the polyethylene of the air-impermeable
packaging material were faced at each other, namely, the non-woven
fabric was exposed; the peripheries of the heat generating
composition molded bodies were heat sealed in a width of 4 mm to
form a sectioned part; the surroundings of the heat cloth as the
outermost surroundings of the heat generating composition molded
bodies were further heat sealed in a width of 8 mm to form a
circumferential seal part. There was thus prepared a heat cloth 1
having an outer diameter length of 100 mm and a width of 55 mm.
[0482] Then, the heat cloth 1 was stuck onto the band 8 via an
acrylic adhesive, thereby preparing a heat cloth 1 of a band body
warmer shape. Incidentally, FIG. 10(b) shows an example in which
the heat cloth 1 is provided in the central part 12.
[0483] The heat cloth of a band body warm shape was sealed in an
outer bag. After lapsing 24 hours, the outer bag was broken, and
the heat cloth was wound around the calf of a leg by a band, fixed
and provided for usual use. As a result, in a portion coming into
contact with the body, which is a lower surface of the heat cloth,
since stretching and non-stretching were repeated, the stretching
part rose and pressed the body, whereby the pressing state was
changed from the plane to a point or a line. Thus, not only the
fitness became very well, but also touch to the skin was good. It
was felt warm within about 3 minutes, and the warmth was continued
for 6 hours or more. During the use, even by the movement, the
stretching part rose and pressed the body in a point-like or linear
state. Thus, a strain caused due to the movement was absorbed by
the stretchability, and the stretching part neither went away nor
came out depending upon the movement of the body so that deviation
or dislocation of the heat cloth 1 of a band body warmer shape did
not occur. The exothermic agent in the material of the invention
did not move at all within the bag, was found to cause uniform heat
generation over the entire surface and was free from swelling.
After the use, the heat cloth 1 could be simply and smoothly
detached and caused neither a pain nor inflammation on the skin. As
a result of carrying out an experiment for use while moving, the
heat cloth 1 did not come down.
Example 11
[0484] FIG. 11 is a plan view to show another example of the band
body warmer of the invention.
[0485] In the drawing, 1 indicates a heat cloth 1 having a pair of
heat cloths 1, 1 formed of seven sectional exothermic parts 2 in
which heat generating composition molded bodies 2B are accommodated
in a rectangular air-permeable bag of 5 mm in thickness.times.100
mm in length.times.55 mm in width as formed in a flat shape. The
pair of heat cloths 1, 1 are stuck in one end side of the surface
of a stretchable non-woven fabric-made band of 1 mm in
thickness.times.400 mm in length.times.60 mm in width while
interposing a space 8B via an acrylic adhesive layer which is a
non-stretchable region. Furthermore, stretchable substrates 8A, 8A
are provided outwardly in the both sides of the pair of heat cloths
1, 1.
[0486] This air-permeable stretchable non-woven fabric-made band 8
having a female fastener function of a hook and loop fastener is
one obtained by heat melting a polyester-made non-woven fabric made
of continuous filaments having a diameter of 15 .mu.m, which is
stretchable in the longitudinal direction, on the both surfaces of
a stretchable urethane based elastomer film and subsequently heat
embossing, thereby not only strengthening the melt but also forming
fine pores.
[0487] Furthermore, as an air-permeable sheet in the surface side
of the heat cloths 1, 1, a non-woven fabric is used, too, on which
a female fastener of a hook and loop fastener is formed.
Incidentally, in the drawing, 9 indicates a male fastener.
[0488] Incidentally, the constitution of the heat cloth 1 having
seven sectional exothermic parts 2 will be described below in
detail. As the heat generating composition, the heat generating
composition of Example 1 was used. Furthermore, as the
air-permeable packaging material, a packaging material having a
moisture permeability by the Lyssy method of 700 g/m.sup.2/24 hr,
in which a 70 .mu.m-thick polyethylene-made porous film was
laminated on a nylon non-woven fabric with a basis weight of 40
g/m.sup.2 and having a female fastener function of a hook and loop
fastener, was used. As the air-impermeable packaging material, a 50
.mu.m-thick polyethylene film was used. Ten heat generating
composition molded bodies of a rectangle of 7 mm in width.times.25
mm in length.times.2 mm in height were provided in intervals of 5
mm on the polyethylene film of the air-impermeable packaging
material by cast molding using a cast die in which ten rectangles
of 7 mm in width.times.25 mm in length.times.2 mm in height were
provided at intervals of 5 mm. Next, the air-permeable packaging
material and the air-impermeable packaging material were overlaid
and laminated such that the porous film surface of the
air-permeable packaging material and the polyethylene film surface
of the air-impermeable packaging material were faced at each other,
namely, the non-woven fabric was exposed; and the surroundings of
the heat generating composition molded bodies were heat sealed in a
seal width of 3 mm, and the surroundings of the heat cloth 1 were
heat sealed in a seal width of 8 mm, thereby producing the heat
cloth 1.
[0489] The heat cloth 1' of a band body warmer shape was sealed in
an outer bag and after lapsing 24 hours, was taken out from the
outer bag. A kneecap was put into a space 8B of the band body
warmer, wound by a band, fixed and then provided for usual use. As
a result, it was felt warm within about 3 minutes, and the warmth
was continued for 6 hours or more. The exothermic agent in the
material of the invention did not move at all within the bag and
was found to cause uniform heat generation over the entire surface.
In long-term use, it was felt comfortable, and after the use, the
entire heat cloth 1' could be simply and smoothly detached and
caused neither a pain nor inflammation on the skin.
[0490] FIG. 12 is an example in which a male fastener 9 of a hook
and loop fastener as the fixing measure of FIG. 11 is provided
crossing bands 8, 8 such that one end side of the bands 8, 8 is not
separated away.
Example 12
[0491] A heat generating mixture consisting of 100 parts by weight
of an iron powder having a wustite content of less than 1%
(particle size: not more than 300 .mu.m), 2.5 parts by weight of
active carbon (particle size: not more than 300 .mu.m), 3 parts by
weight of a water absorptive polymer (particle size: not more than
300 .mu.m), 0.5 parts by weight of calcium hydroxide, 0.7 parts by
weight of sodium sulfite and 5 parts by weight of 11% salt water
and having a water mobility value of not more than 0.01 was charged
in a contact treatment device vessel. Next, the upper portion of
the contact treatment device vessel was opened to air, and the
reaction mixture was subjected to a self heat generation with
stirring in the opened state to air under circumferences at
20.degree. C. At a point of time when the temperature rise of the
reaction mixture reached 10.degree. C., 11% salt water was mixed to
obtain a heat generating composition having a water mobility value
of 10. Next, by using the heat generating composition and using the
same substrate and covering material and the same manner as in
Example 1, twenty heat generating molded bodies constituting a
sectional exothermic part were provided on the surface of a
polyethylene film of a substrate made of a laminate of a nylon-made
non-woven fabric and a polyethylene film by force-through molding
using a trimming die having twenty cavities of 5 mm in
width.times.80 mm in length at intervals of 5 mm. Next, an
air-permeable covering material made of a laminate of a
polyethylene-made porous film and a nylon-made non-woven fabric was
covered thereon, and the peripheries of the respective heat
generating composition molded bodies and the surroundings of the
heat cloth were sealed. The surroundings of the respective
sectional exothermic parts were heat sealed in a seal width of 3
mm, the surroundings of the heat cloth were sealed in a seal width
of 8 mm, and the central exothermic parts were sealed in a width of
8 mm, thereby obtaining a heat cloth having an external dimension
of 211 mm in length.times.96 mm in width. This heat cloth was
sealed and accommodated in an outer bag and allowed to stand at
room temperature for 24 hours. After 24 hours, the heat cloth was
taken out from the outer bag and then subjected to an exothermic
test of the body. As a result, it was felt warm within 3 minutes,
and the warmth was continued for 8 hours. At the same time, curved
surface fitness, winding properties and usefulness were evaluated.
As a result, the heat cloth was superior in all of these
evaluations. Incidentally, the external dimension is not
particularly limited, and for example, one having an external
dimension of 1 m and a width of 96 mm can be formed.
Example 13
[0492] As a heat generating composition, a heat generating
composition having a water mobility value of 8, which is a mixture
consisting of 100 parts by weight of a reduced iron powder
(particle size: not more than 300 .mu.m), 7.0 parts by weight of
active carbon (particle size: not more than 300 .mu.m), 5.0 parts
by weight of a wood meal (particle size: not more than 300 .mu.m),
0.8 parts by weight of a water absorptive polymer (particle size:
not more than 300 .mu.m), 0.2 parts by weight of calcium hydroxide,
0.7 parts by weight of sodium sulfite and 11% of salt water, was
used. Next, by using the heat generating composition, five heat
generating molded bodies constituting a sectional exothermic part
were provided on the surface of a polyethylene film of a substrate
made of a 30 .mu.m-thick acrylic adhesive layer-provided
polyethylene film as provided with a separator by force-through
molding using a trimming die having five cavities of 5 mm in
width.times.80 mm in length at intervals of 5 mm.
[0493] Next, an air-permeable covering material made of a laminate
of a polyethylene-made porous film on a nylon-made non-woven fabric
with a basis weight of 40 g/m.sup.2 was passed through a folding
machine composed of a pair of folding tools having a concavo-convex
surface and folded in a wavy shape. Then, valleys of the covering
material were pressed onto the substrate by using one of the
folding tools having a concavo-convex surface; the heat generating
composition molded bodies constituting a sectional exothermic part
were wrapped and covered within crests of the covering material;
and the covering material and the substrate in a corresponding
region of the sectioned part were heat sealed. Next, the
peripheries of the heat generating composition molded bodies were
heat sealed, and the surroundings of the heat cloth were further
heat sealed, thereby obtaining a heat cloth having an exothermic
part made of sectional exothermic parts in a stripe form. The
sectioned part which is a seal part of the periphery of the
respective heat generating composition molded body was heat sealed
in a seal width of 3 mm, thereby preparing the sectional exothermic
part as sectioned by the sectioned part. Furthermore, by sealing
the surroundings of the heat cloth in a seal width of 8 mm, the
heat cloth having a sectional exothermic part in a stripe form of
98 mm in length.times.91 mm in width in terms of an external
dimension was obtained. Incidentally, the air permeability of the
air-permeable covering material was 400 g/m.sup.2/24 hr in terms of
a moisture permeability by the Lyssy method. This heat cloth was
sealed and accommodated in an air-impermeable accommodating bag
(hereinafter referred to as "outer bag") and allowed to stand at
room temperature for 24 hours. After 24 hours, the heat cloth was
taken out from the outer bag and then subjected to an exothermic
test of the body. As a result, it was felt warm within 3 minutes,
and the warmth was continued for 7 hours. At the same time, curved
surface fitness, winding properties and usefulness were evaluated.
As a result, the heat cloth was superior in all of these
evaluations.
Example 14
[0494] FIG. 13 shows examples of the shape of the heat cloth of the
invention.
[0495] (a) shows a broad bean-like shape; (b) shows an eye
mask-like shape; (c) shows a cocoon-like shape; (d) shows a
gourd-like shape; (e) shows a rectangular shape with rounded
corners; (f) shows a rectangular shape; (g) shows a square shape
with rounded corners; (h) shows a square shape; (i) shows an
egg-like shape; (j) shows a boomerang-like shape; (k) shows a
comma-shaped bead-like shape; (l) shows a wing-like shape; (m)
shows a wing-like shape; (n) shows a star-like shape; (o) shows a
nose-like shape; (p) shows a paper lantern-like shape; and (q)
shows a paper lantern-like shape, respectively.
[0496] Furthermore, while the directions of the long axes along the
long sides of the rectangles of the sectional exothermic parts are
parallel to each other, they may be arbitrarily set up. Also, a
gathering of sectional exothermic parts in different directions may
be employed. Modified shapes as modified on the basis of these
basic skeletons can also be used.
Example 15
[0497] FIG. 14 shows an embodiment of the force-through molding
method using a leveling plate 15. That is, a substrate 3 in a roll
film form having a width of 130 mm and a thickness of 1 mm is
adapted to a molding mold 12 having a thickness of 1.5 mm and
having a desired shape punched out in the center thereof and
horizontally sent at a prescribed speed between a die 11 as
disposed in the upper surface and a magnet 13 as disposed in the
lower surface. The heat generating composition 2 of the invention
is sent into a mold hole 12a from the upper surface of the mold 12
through a hole 11a of the die 11. The heat generating composition
2' is leveled in the same level as in the mold 12 by a leveling
plate 15 as placed forward in the advancing direction and
accommodated in the mold hole 12a, whereby a shape having a
thickness of 1.5 mm is molded on the substrate 3. Thereafter, the
mold 12 is removed to obtain a heat generating composition molded
body as laminated on the substrate 5. While not illustrated, a
styrene-isoprene-styrene block copolymer (SIS) based sticky polymer
is then provided in a netlike form on the surface of the foregoing
molded body by the melt blow method, a covering material is covered
thereon, and the periphery of the molded body is sealed by heat
seal, followed by cutting into a desired shape. There is thus
obtained a heat cloth having a desired shape. In addition, the cut
heat cloth of the invention is subsequently sent into a packaging
step and sealed in an air-tight outer bag. Furthermore, the same
molding is possible even by changing the leveling plate to a
pushing leveling plate. FIG. 15 shows an enlarged view of the
leveling plate 15.
* * * * *