U.S. patent application number 12/266428 was filed with the patent office on 2010-05-06 for structure for cooling.
This patent application is currently assigned to OHSHIN MLP CO., LTD.. Invention is credited to Keizo Ota, Tetsuhiro Watanabe.
Application Number | 20100108287 12/266428 |
Document ID | / |
Family ID | 42130015 |
Filed Date | 2010-05-06 |
United States Patent
Application |
20100108287 |
Kind Code |
A1 |
Ota; Keizo ; et al. |
May 6, 2010 |
STRUCTURE FOR COOLING
Abstract
A structure for cooling having a cover and a water-retentive
member, wherein the water-retentive member includes a bag and a
water-absorptive material disposed inside the bag, wherein the
water-retentive member is disposed inside the cover, wherein the
first side of the cover having a moisture-permeability of 500 to
3,000 g/m.sup.224 hours, as determined by the Lyssy Method; a first
side of the bag is moisture- or water-permeable; and at least one
of a second side of the cover and a second side of the bag is
water-impermeable.
Inventors: |
Ota; Keizo; (Fukui, JP)
; Watanabe; Tetsuhiro; (Fukui, JP) |
Correspondence
Address: |
OSHA LIANG L.L.P.
TWO HOUSTON CENTER, 909 FANNIN, SUITE 3500
HOUSTON
TX
77010
US
|
Assignee: |
OHSHIN MLP CO., LTD.
Fukui
JP
|
Family ID: |
42130015 |
Appl. No.: |
12/266428 |
Filed: |
November 6, 2008 |
Current U.S.
Class: |
165/46 ;
165/134.1 |
Current CPC
Class: |
A61F 2007/026 20130101;
A61F 2007/0258 20130101; A61F 2007/0098 20130101; A61F 7/10
20130101; A61F 2007/0214 20130101; A01K 13/006 20130101; A61F 7/02
20130101 |
Class at
Publication: |
165/46 ;
165/134.1 |
International
Class: |
F28F 7/00 20060101
F28F007/00; F28F 19/00 20060101 F28F019/00 |
Claims
1. A structure for cooling, comprising: a cover having a first side
and a second side, and a water-retentive member, wherein the
water-retentive member comprises a bag having a first side and a
second side, and a water-absorptive material disposed inside the
bag, wherein, the water-retentive member is disposed inside the
cover; wherein the first side of the cover has a
moisture-permeability of 500 to 3,000 g/m.sup.224 hours as
determined by the Lyssy Method; wherein the first side of the bag
is moisture-permeable or water-permeable; and at least one of the
second side of the cover and the second side of the bag is
water-impermeable.
2. The structure of claim 1, wherein the first side of the cover
comprises a fibrous layer and an air-permeable sheet layer.
3. The structure of claim 2, wherein the air-permeable sheet layer
is an air-impermeable polymer film having openings.
4. The structure of claim 1, wherein the first side of the bag is
made of a fibrous material.
5. The structure of claim 4, wherein the fibrous material is a
nonwoven fabric.
6. The structure of claim 1, wherein the water-absorptive material
comprises (1) a water-absorptive sheet with a water-absorptive
polymer, or (2) a water-absorptive sheet with a water-absorptive
polymer and a water-absorptive sheet without a water-absorptive
polymer.
7. The structure of claim 1, wherein the second side of the cover
is water-impermeable and comprises a fibrous layer and an
air-impermeable sheet layer, wherein the fibrous layer and the
air-impermeable sheet layer are partially or completely bonded
together.
8. The structure of claim 1, wherein the second side of the bag is
water-impermeable and comprises a nonwoven fabric and an
air-impermeable sheet layer, wherein the nonwoven fabric and the
air-impermeable sheet layer are partially or completely bonded
together.
9. The structure of claim 1, wherein the water-retentive member
comprises an antifungal agent.
10. The structure of claim 6, wherein the water-absorptive polymer
comprises an antifungal agent.
11. A structure for cooling, comprising: a cover having a first
side and a second side, and a water-retentive member, wherein the
water-retentive member comprises a bag having a first side and a
second side, and a water-absorptive polymer that is adhered to an
inner surface of at least one of the first side and the second side
of the bag, or that is disposed in at least one of the first side
and the second side of the bag, wherein the water-retentive member
is disposed inside the cover; wherein the first side of the cover
has a moisture-permeability of 500 to 3,000 g/m.sup.224 hours as
determined by the Lyssy Method; wherein the first side of the bag
is moisture-permeable or water-permeable; and wherein at least one
of the second side of the cover and the second side of the bag is
water-impermeable.
12. The structure of claim 11, wherein the first side of the cover
comprises a fibrous layer and an air-permeable sheet layer.
13. The structure of claim 12, wherein the air-permeable sheet
layer is an air-impermeable polymer film having openings.
14. The structure of claim 11, wherein the first side of the bag is
made of a fibrous material.
15. The structure of claim 14, wherein the fibrous material is a
nonwoven fabric.
16. The structure of claim 11, further comprises water-absorptive
material disposed in the bag.
17. The structure of claim 16, wherein the water-absorptive
material comprises (1) a water-absorptive sheet with a
water-absorptive polymer, or (2) a water-absorptive sheet with a
water-absorptive polymer and a water-absorptive sheet without a
water-absorptive polymer.
18. The structure of claim 11, wherein the second side of the cover
is water-impermeable comprising a fibrous layer and an
air-impermeable sheet layer, wherein the fibrous layer and the
air-impermeable sheet layer are partially or completely bonded
together.
19. The structure of claim 11, wherein the second side of the bag
is water-impermeable comprising a fibrous material and an
air-impermeable sheet layer, wherein the fibrous material and the
air-impermeable sheet layer are partially or completely bonded
together.
20. The structure of claim 11, wherein the water-retentive member
comprises an antifungal agent.
21. The structure of claim 11, wherein the water-absorptive polymer
comprises an antifungal agent.
22. The structure of claim 17, wherein the water-absorptive polymer
comprises an antifungal agent.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is related to a Japanese patent
application: Japanese Patent Early-publication No. 2007-289594,
published on Nov. 8, 2007.
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a structure having a
water-retentive member for cooling human or animal bodies.
[0004] 2. Background Art
[0005] Absorptive substances that can be used as a disposable
diaper and the like usually comprise a liquid-permeable sheet, a
liquid-impermeable sheet, and a water-absorptive material, which
may be placed between the liquid-permeable sheet and the
liquid-impermeable sheet. The water-absorptive material may
comprise fibrous base materials such as a nonwoven fabric and
water-absorptive resins or highly water-absorptive polymers held to
the fibrous base materials. Paper may also be used with the
water-absorptive material.
[0006] Japanese Patent Early-publication No. 2004-358797 discloses
a liner for incontinence. This liner includes (1) a
water-absorptive composite sheet comprising a water-absorptive
sheet containing a fibrous base material and water-absorptive resin
particles attached to the fibrous base material and a fibrous base
sheet, and that is mounted on at least one side of the
water-absorptive sheet, (2) a nonwoven fabric, and (3) a
polyethylene sheet. The water-absorptive composite sheet is put
between the nonwoven fabric and the polyethylene sheet. This
reference discloses that the water-absorptive composite sheet is a
highly effective water absorbing material that can absorb large
amount of liquids such as urine at high speed.
[0007] Japanese Patent Early-publication No. 2001-286505 discloses
an absorptive substance having a liquid-permeable sheet, a
liquid-impermeable sheet, and an absorptive material having
liquid-retentive property disposed between these two sheets. The
absorptive material contains a first absorptive layer having highly
water-absorptive polymers held between nonwoven fabric fibers and a
second absorptive layer having aggregates of hydrophilic fibers.
The first absorptive layer faces the liquid-permeable sheet and the
second absorptive layer faces the liquid-impermeable sheet. This
reference, thus, discloses a substance that can prevent liquids,
e.g., urine, from moving back.
[0008] The water-absorptive resin or the highly water-absorptive
polymer has been used in cooling materials with water in gelatinous
state.
[0009] Japanese Patent Early-publication No. 2005-118059 discloses
a cooling material having a cooling agent that contains a cooling
medium. The cooling medium may be a gelatinous substance of a
water-absorptive resin containing the resin and water or a
water/solvent mixture. The cooling medium is placed in a sealed
container made of a water-permeable and water-insoluble base
material. At least part of the outer surface of the cooling
material is made of a wrapping material that is made of a fibrous
and/or plastic three-dimensional structure with air-permeability of
at least 200 cm.sup.3/cm.sup.2/second (Fragile method). This
reference discloses that this material has its cooling effect due
to latent heat of water vaporization.
[0010] Japanese Utility Model Early-publication No. 2001-104359
discloses a cooling sheet that contains aqueous gel applied on one
side of a water-absorptive nonwoven fabric sheet made of fibrous
water-absorptive resins and/or water-retentive fibers. The cooling
effect of this sheet is due to heat of water vaporization. This
reference also discloses that water is sprayed onto the surface of
the water-absorptive nonwoven fabric when the cooling sheet is
prepared.
[0011] Examples of conventional cooling substances/sheets as
described above use latent heat of water vaporization or heat of
gasification of water to achieve the cooling effect. However, after
water vaporization ceases, the cooling effect is no longer
available.
[0012] The Mie Chemical Co., Ltd.
(http://miekagaku.co.jp/sp04.html) discloses a cooling substance
containing highly water-absorptive polymers. The cooling substance
is soaked in water to absorb the water and then frozen before
use.
[0013] Among inventions that use cooling effects due to latent heat
of vaporization of water, the following ones are also known.
[0014] Japanese Patent Early-publication No. HEI. 11-28034
discloses a cooler mat for pets having (1) a pouch-like member,
which comprises water-absorptive polymers placed into a wrapping
(pouch-like structure) having a sheet made of an air-permeable
material on its first side and another sheet made of a synthetic
resin on its second side, and (2) an outer wrapping, which is made
of an air-permeable material, for storing the pouch-like member. In
this cooler mat, the pouch-like member is soaked in water before
use. The water, that has been held by the water-absorptive polymer
vaporizes, goes out as a vapor through the sheet made of the
air-permeable material on the first side of the pouch-like member
and through the outer wrapping material that stores the pouch-like
member. The latent heat of vaporization of water results in cooling
effects.
[0015] The cooler mat in the above reference (Japanese Patent
Early-publication No. HEI. 11-28034) has problems. The first
problem is that the cooling efficiency is not controlled, and the
second one is that the outer wrapping, which is made of an
air-permeable material, e.g., a nonwoven fabric, may become damp by
the water vapor coming from the water-absorptive polymers. These
problems should be solved before the device is used in human.
[0016] Japanese Patent Early-publication No. 2001-120095 discloses
a cooler mat for pets. This cooler mat contains a water-permeable
pouch-like member in which water-absorptive polymers are placed;
and a bag for storing the pouch-like member. In addition, the
water-permeable pouch-like member has many polymer-stuffed areas,
the peripheries of which are heat-sealed. The water-permeable
pouch-like member is soaked in water before use. The bag can be
made of an air-permeable material on one side and a
water-repellency material on the other side. Alternatively, the bag
can be made of water-repellent materials as the inner layer and
fabric as the outer layer. Thus, the water vapor from the
water-permeable pouch-like member can go out through the bag
causing a cooling effect by heat of water vaporization. However,
the control of the cooling efficiency is not considered in this
device. Additionally, the part of the bag made of the air-permeable
material may become damp by the water vapor from the
water-permeable pouch-like member. Again, there are problems that
need to be solved before human use. In the case that the outside of
the bag does not become damp by the water vapor from the
water-permeable pouch-like member, the bag may be saturated by the
water vapor, resulting in limited cooling effects.
SUMMARY OF INVENTION
[0017] Embodiments of the present invention relate to structures
for cooling. These structures may enable controlled cooling
efficiency by using latent heat of water vaporization (or heat of
gasification of water). By replenishing water, such a structure for
cooling may be used repeatedly for a long time. Specifically,
embodiments of the present invention relate to structures for
cooling, in which the outer surface of each structure cover is less
likely to become damp by the moisture coming from a water-holding
substance disposed inside the structures. The present invention
also relates to structures for cooling that may eliminate or
minimize fungal contamination.
[0018] The first aspect of the invention relates to structures for
cooling. A structure for cooling in accordance with one embodiment
of the invention may have a cover and a water-retentive member. The
water-retentive member may comprises a bag and a water-absorptive
material disposed inside the bag. The water-retentive member may be
removed from the cover. Referring to FIG. 3(1), a first side a of
the cover may have an outer fibrous layer and an inner
air-permeable sheet layer partially bonded together. The first side
a of the cover may have a moisture-permeability of 500 to 3,000
g/m.sup.224 hours, as determined by the Lyssy Method. The first
side I of the bag may be made of a moisture- or water-permeable
material. At least one of the second side b of the cover (i.e., the
opposite side of the first side of the cover) and the second side
II of the bag (i.e., the opposite side of the first side of the
bag) is water-impermeable.
[0019] In one example of embodiments of the invention, the
air-permeable sheet layer may be an air-impermeable polymer film
having openings, e.g., a porous film that is
moisture-permeable.
[0020] In another example of embodiments of the invention, the
first side I of the bag may be made of a fibrous material,
preferably a nonwoven fabric.
[0021] In another example of the first embodiment of the invention,
the water-absorptive material may be (1) a water-absorptive
sheet(s) with a water-absorptive polymer, or (2) a water-absorptive
sheet(s) with a water-absorptive polymer and a water-absorptive
sheet(s) without a water-absorptive polymer.
[0022] In another example of embodiments of the invention, the
water-impermeable second side b of the cover (i.e., the opposite
side of the first side of the cover) may contain an outer fibrous
layer and an inner air-impermeable sheet layer partially or
completely bonded together.
[0023] In another example of embodiments of the invention, the
water-impermeable second side II of the bag (i.e., the opposite
side of the first side of the bag) may contain a nonwoven fabric
and an air-impermeable sheet layer partially or completely
(preferably completely) bonded together. The air-impermeable sheet
layer may be disposed on the outside or the inside of the nonwoven
fabric, and preferably on the outside of the nonwoven fabric.
[0024] In another example of embodiments of the invention, the
water-retentive member, preferably the water-absorptive polymer,
may contain an antifungal agent.
[0025] Another aspect of the invention relates to a structure for
cooling. The structure may have a cover and a water-retentive
member. The water-retentive member may have a bag and a
water-absorptive material disposed inside the bag. The
water-retentive member may be removed from the cover. Referring to
FIG. 3, the first side a of the cover may have an outer fibrous
layer and an inner air-permeable sheet layer partially bonded
together. The first side a of the cover may have a
moisture-permeability of 500 to 3,000 g/m.sup.224 hours, as
determined by the Lyssy Method. The second side b of the cover
(i.e., the opposite side of the first side of the cover) may
contain an outer fibrous layer and an inner air-impermeable sheet
layer partially or completely bonded together. The water-retentive
member may contain a bag made of a nonwoven fabric and disposed
inside the bag a water-absorptive sheet that may contain a
water-absorptive polymer.
[0026] In accordance with embodiments of the invention, one example
of a water-absorptive material containing a water-absorptive
sheet(s) with a water-absorptive polymer and a water-absorptive
sheet(s) without a water-absorptive polymer is as follows: Inside
the bag of the water-retentive member, the water-absorptive sheet
that is disposed as one of the outermost layers among
water-absorptive sheet layers may have the water-absorptive
polymer. The outer surface of one side of the bag, of which inner
surface faces the water-absorptive sheet containing the
water-absorptive polymer, faces the first side a of the cover.
[0027] In accordance with some embodiments of the invention,
another example of a water-absorptive material having a
water-absorptive sheet(s) with a water-absorptive polymer and a
water-absorptive sheet(s) without a water-absorptive polymer is as
follows: Inside the bag of the water-retentive member, the
water-absorptive sheet, that is disposed next to (inside of) one of
the outermost layers among water-absorptive sheet layers, may have
the water-absorptive polymer. The outer surface of one side of the
bag, of which inner surface faces the outermost water-absorptive
sheet layer next to (outside of) the water-absorptive sheet
containing the water-absorptive polymer, faces the first side a of
the cover.
[0028] Another aspect of the invention also relates to a structure
for cooling. The structure may contain a cover and a
water-retentive member. The water-retentive member may have a bag
and a water-absorptive polymer. The water-absorptive polymer may
adhere to an inner surface(s) of at least one side of the bag or
may be disposed in at least one side of the bag. The
water-retentive member may be removed from the cover. The first
side a of the cover comprises an outer fibrous layer and an inner
air-permeable sheet layer partially bounded together. The first
side a of the cover may have a moisture-permeability of 500 to
3,000 g/m.sup.224 hours, as determined by the Lyssy Method. The
first side I of the bag may contain a moisture- or water-permeable
material. At least one of the second side b of the cover (i.e., the
opposite side of the first side of the cover) and the second side
II of the bag (i.e., the opposite side of the first side of the
bag) may be water-impermeable.
[0029] In one example of one embodiment of the invention, the
air-permeable sheet layer may be an air-impermeable polymer film
having openings, e.g., a porous film that is
moisture-permeable.
[0030] In another example of another embodiment of the invention,
the first side I of the bag may be made of a fibrous material,
preferably a nonwoven fabric.
[0031] In another example of another embodiment of the invention,
the cooling structure may farther include water-absorptive material
disposed inside the bag. The water-absorptive material may be
preferably (1) a water-absorptive sheet(s) with a water-absorptive
polymer, or (2) a water-absorptive sheet(s) with a water-absorptive
polymer and a water-absorptive sheet(s) without a water-absorptive
polymer.
[0032] In another example of another embodiment of the invention,
the other water-impermeable second side b of the cover (i.e., the
opposite side of the first side of the cover) may contain an outer
fibrous layer and an inner air-impermeable sheet layer partially or
completely bonded together.
[0033] In another example of one embodiment of the invention, the
other water-impermeable second side II of the bag (i.e., the
opposite side of the first side of the bag) may contain a fibrous
material, preferably a nonwoven fabric, and an air-impermeable
sheet layer partially or completely (preferably completely) bonded
together. The air-impermeable sheet layer may be disposed outside
the fibrous material.
[0034] In another example of another embodiment of the invention,
the water-retentive member, preferably the water-absorptive polymer
may contain an antifungal agent.
[0035] Another aspect of the invention relates to structures for
cooling. A structure may contain a cover and a water-retentive
member. The water-retentive member may be removed from the cover.
The first side a of the cover may contain an outer fibrous layer
and an inner air-permeable sheet layer partially bonded together.
The first side a of the cover may have a moisture-permeability of
500 to 3,000 g/m.sup.224 hours, as determined by the Lyssy Method.
The second side b of the cover (i.e., the opposite side of the
first side of the cover) may contain an outer fibrous layer and an
inner air-impermeable sheet layer partially or completely bonded
together. The water-retentive member may contain a bag made of a
nonwoven fabric. The inner surface of at least one side of the bag
may contain a water-absorptive polymer.
[0036] Other aspects and advantages of the invention will be
apparent from the following description and the appended
claims.
BRIEF DESCRIPTION OF DRAWINGS
[0037] FIG. 1 is a schematic view of the cover of one example of a
structure in accordance with one embodiment of this invention,
wherein the fastener of the cover is opened.
[0038] FIG. 2 is a schematic view of the same example of the cover
of a structure in accordance with one embodiment of this invention,
wherein the fastener of the cover is closed.
[0039] FIGS. 3(1)-3(4) show sectional views of examples of a cover
in accordance with one embodiment of this invention.
[0040] FIG. 4 is a sectional view of one example of a
water-retentive member in accordance with one embodiment of this
invention.
[0041] FIG. 5 is a sectional view of another example of a
water-retentive member in accordance with one embodiment of this
invention.
[0042] FIG. 6 is a sectional view of another example of a
water-retentive member in accordance with one embodiment of this
invention.
[0043] FIG. 7 is a sectional view of another example of a
water-retentive member in accordance with one embodiment of this
invention.
[0044] FIG. 8 is a sectional view of another example of a
water-retentive member in accordance with one embodiment of this
invention.
[0045] FIG. 9 is a sectional view of one example of a structure in
accordance with one embodiment of this invention.
[0046] FIG. 10 is a sectional view of one example of a
water-absorptive sheet containing a water-absorptive polymer in
accordance with one embodiment of the invention.
[0047] FIG. 11 shows surface temperature changes, as a function of
time, of cooling structures in accordance with embodiments of the
invention.
[0048] FIG. 12 shows results of cooling of various parts of users
by cooling structures in accordance with embodiments of the
invention.
DETAILED DESCRIPTION
[0049] Embodiments of the invention relate to structures having
water-retentive members for cooling. In the following detailed
description of the subject matter of the present invention, the
cooling structures are principally described as being used for
cooling human or animal bodies. For example, a structure for
cooling according to one embodiment of the present invention may be
used as a bed pad, a pad on a futon, or a rug for pets. Hereafter,
the present invention will be explained with reference to preferred
embodiments. Such examples or applications are intended for
illustration purposes only and are not intended to limit the scope
of the present invention.
[0050] FIGS. 1 and 2 are schematic views of a cover 100 of one
example of a structure in accordance with one embodiment of this
invention, wherein a fastener F of the cover 100 is opened (FIG. 1)
or closed (FIG. 2). FIG. 3 shows sectional views of examples of a
first side a and a second side b of the cover 100. FIG. 9 also
shows a sectional view of one example of the cover 100.
[0051] Referring to FIG. 1 and FIG. 2, the cover 100 has a fastener
F that may be sewed in the peripheries of the cover 100. By closing
the fastener F, the cover 100 may exhibit a baggy form as shown in
FIG. 2. The specific form of the cover100, though preferably baggy,
is not restricted to the example shown as long as a water-retentive
member (shown as 200 in FIG. 4) may be put into and withdrawn from
the cover 100.
[0052] FIG. 3(1) shows that the first side a of the cover 100 has a
fibrous layer 1 at the outside and an air-permeable sheet layer 3
at the inside. The fibrous layer 1 may be partly bonded to the
air-permeable sheet layer 3.
[0053] The first side a of the cover 100 may have a
moisture-permeability of 500 to 3,000 g/m.sup.224 hours, preferably
700 to 2,000 g/m.sup.224 hours, and more preferably 1,000 to 1,500
g/m.sup.224 hours, as determined by the Lyssy Method (JIS Z0208;
ASTM E398). The moisture-permeability may affect the amount of
water vapor that passes through the first side a. The higher the
moisture-permeability is, the higher the cooling effect would be
due to a larger amount of water being vaporized.
[0054] If a structure for cooling according to the present
invention is used for sleep in summer, it is preferable that the
surface temperature of human body may be lowered by 1 to 2 degrees
Celsius. If the structure is used for refrigeration in a medical
care field, the surface temperature of human body may be lowered by
about 4 degrees Celsius. In the latter case, the first side a
(air-permeable side) of the cover 100 has a moisture-permeability
of preferably 1,000 to 2,000 g/m.sup.224 hours, and more preferably
1,400 to 1,800 g/m.sup.224 hours, as determined by the Lyssy
Method.
[0055] Determination of the moisture-permeability based on the
Lyssy Method may be performed at 40 degrees Celsius under a
humidity difference of about 90%. More specifically, in an example
of the Lyssy Method, a test sample may be set between an atmosphere
x having a relative humidity of 100% and an atmosphere y having a
relative humidity of 9%, and a time required to achieve a relative
humidity of 11% in the atmosphere y may be determined. Known
moisture-permeability of standard samples are also determined. By
comparing the data of the test sample to the data of the standard
samples, the moisture-permeability of the test sample may be
determined.
[0056] Moisture-permeability ranges described above are meant for
averages of the useable portions of an article, while local areas
or areas not intended to be in contact with a user may have
moisture permeability outside of the desired range. For example,
portions(s) of side a, e.g., four peripheries, may have a
moisture-permeability outside of the above-mentioned range. In
other word, the substantially whole part (e.g., parts where used
for cooling) of the one side a of the cover 100 may have a
moisture-permeability within the above range.
[0057] FIG. 3(2) shows one embodiment of the invention, in which
the second side b of the cover 100 may contain a fibrous layer 7 at
the outside and an air-impermeable sheet layer 5 at the inside. In
this example, the fibrous layer 7 is bonded to the air-impermeable
sheet layer 5.
[0058] FIG. 3(3) shows another example of the second side b of the
cover 100. In this example, the second side b may contain an
air-impermeable sheet layer 5 only. To prevent the transpiration of
water that has been held by the water-retentive member through the
cover 100, the air-impermeable sheet layer 5 having a repellent or
water-proofing property may be used.
[0059] Referring again to FIG. 3(2), the fibrous layer 7 may be
bonded completely or partly to the air-impermeable sheet layer 5.
It is preferable that they are completely bonded to each other. The
bonding may be achieved by fusing the polymers in the fibrous layer
7 or the air-impermeable sheet layer 5, or by using an adhesive or
other suitable means.
[0060] FIG. 3(4) shows, if the second side II of a bag of the
water-retentive member (shown as 9 in FIG. 4) is water-impermeable,
the second side b of the cover 100 may be made of a water-permeable
material such as fibrous materials 7.
[0061] When a structure for cooling according to embodiments of the
present invention is used, the first side a may be the top side
(right side or usable side) and the second side b may be the bottom
side (wrong side). For example, if the structure for cooling is a
bed pad, the first side a would face human body and the second side
b would face a mattress.
[0062] In the first embodiment of the invention, the
water-retentive member may contain a bag and a water-absorptive
material disposed inside the bag. The one side I of the bag may be
made of a moisture or water-permeable material. The other side II
of the bag may be made of a moisture or water-permeable material or
a water-impermeable material.
[0063] FIG. 4 shows a sectional view of one example of a
water-retentive member 200 of a structure according to one
embodiment of the invention. The water-retentive member 200 may
include a bag 9 made of a nonwoven fabric and a water-absorptive
sheet 15 that may contain a water-absorptive polymer. The first
side I and the second side II of the bag 9 may be made of a
nonwoven fabric that is moisture or water-permeable. Alternatively,
the first side I of the bag 9 may be made of a moisture or water
permeable material 9a, while the second side II of the bag 9 may be
made of a moisture or water-impermeable material 9b. The
water-absorptive sheet 15 may contain a water-absorptive polymer or
any water-absorptive material. The water-absorptive sheet 15 may
preferably have an overall sheet configuration. However, other
shapes or configurations may also be used without departing from
the scope of the invention.
[0064] The water-retentive member 200 (shown in FIG. 4) may be put
into the cover 100 (shown in FIG. 1 and FIG. 2) so that the first
side I (9a) of the bag 9 faces a side a (an air-permeable side) of
the cover 100, and the second side II (9b) faces the second side b
of the cover 100.
[0065] FIG. 10 shows an example of a water-absorptive sheet 15,
which may comprises a water-absorptive polymer 11 and a support
sheet 13. The water-absorptive polymer 11 may be disposed on
(coated on, adhered to, etc.) one side of the support sheet 13.
When the water absorptive sheet 15 is put into the bag 9, the water
absorptive polymer preferably faces or touches the first side I
(9a) of the bag 9 (see FIG. 4).
[0066] Alternatively, a water-absorptive sheet 15 may comprise the
water-absorptive polymer 11 compounded into the support sheet 13,
i.e., the polymer 11 may be mixed into the support sheet 13. In
this alternative embodiment, both sides of the water-absorptive
sheet 15 will be similar. Thus, when the water-retentive member
(shown as 200 in FIG. 4) is put into the cover 100 (shown in FIGS.
1 and 2), either the first side I (9a) or the second side II (9b)
may face the first side a of the cover 100.
[0067] FIG. 5 shows a sectional view of another example of a
water-retentive member 300 of a structure for cooling according to
one embodiment of the invention. The member 300 may comprise: (1) a
bag 9 made of a nonwoven fabric, (2) a first water-absorptive sheet
15 containing a water-absorptive polymer 11 and a support sheet 13,
and (3) a second water-absorptive sheet 17 without a
water-absorptive polymer. The first water absorptive sheet 15 and
the second water-absorptive sheet 17 are placed inside the bag 9.
The bag 9 may contain a first side I (9a) and a second side II
(9b), which may be made of a nonwoven fabric moisture- or
water-permeable material. Among the water-absorptive sheets as
water-absorptive materials, the water-absorptive sheet 15 may be
set as the outermost layer that faces or touches the first side I
(9a) of the bag 9.
[0068] The water-retentive member 300 may be put into a cover
(shown as 100 in FIG. 1 and FIG. 2) so that the first side I (9a)
of the bag 9 made of a nonwoven fabric faces the first side a of
the cover 100.
[0069] FIG. 6 shows a sectional view of another example of a
water-retentive member 400 of a structure for cooling according to
one embodiment of the invention. In the water-retentive member 400,
a bag P is a modified version of bag 9 shown in FIG. 4. Bag P may
be made of an air-impermeable sheet layer 19 bonded onto the inner
surface of the second side II of the bag 9. The first side I of the
bag P may be made of a nonwoven fabric 9a that is a moisture- or
water-permeable, while the second side II of the bag P may be
water-impermeable and made of an air-impermeable sheet layer 19 and
a nonwoven fabric 9b. The air-impermeable sheet layer 19 may be
partly or completely bonded onto the inner surface of the nonwoven
fabric 9b. The bonding may be achieved by fusing the polymer within
the air-impermeable sheet layer 19 or the nonwoven fabric 9b, or by
using an adhesive or other suitable means. In the water-retentive
member 400, the air-impermeable sheet layer 19 may also be on the
outer peripheries of the bag, namely, parts where the side 9a may
be bonded to the side 9b.
[0070] Because of the air-impermeable sheet layer 19, the water
that has been held by the water-absorptive materials, i.e.,
water-absorptive sheets 21, 23, and 25, and a water-absorptive
sheet 15 that may contain a water-absorptive polymer, may be held
within the water retentive member 400 without going out through the
side II.
[0071] Inside the bag P, there may be water-absorptive sheets 21,
23, and 25, and a water-absorptive sheet 15 having a
water-absorptive polymer 11. In this case, the sheet 15 may be
placed second to the outermost water-absorptive sheet 21. Thus, the
water held by the water-absorptive sheet 21 may be absorbed by the
water-absorptive polymer 11 on the water-absorptive sheet 15,
ensuring a smooth transfer of water to the polymer 11.
[0072] The water-retentive member 400 may be put into the cover
(shown as 100 in FIG. 1 and FIG. 2) so that the side I of the bag P
faces the side a of the cover 100. FIG. 4-6 show the examples
wherein the water-absorptive sheets may not need to be fixed.
However, the water-absorptive sheets may be fixed by placing the
outer peripheries of the water-absorptive sheets between the first
side I (9a) and the second side II (9b) in the outer peripheries of
the bag 9 and by bonding the water-absorptive sheets to the first
side I (9a) and the second side II (9b).
[0073] FIG. 9 shows a water-retentive member 700 of a structure for
cooling in accordance with one embodiment of the invention. A first
side I of the bag P may include entire nonwoven fabric 9x, parts of
a nonwoven fabric 9y (i.e., parts on or above the dotted lines that
traverse the nonwoven fabric 9y1, namely, parts 9y1 and 9y3), and
parts of an air-impermeable sheet layer 19 (i.e., parts on or above
the dotted lines that traverse the air-impermeable sheet layer 19,
namely, parts 19y1 and 19y3). The second side II of the bag P may
include the residual part of the nonwoven fabric 9y (i.e., the part
under the dotted lines that traverse the nonwoven fabric 9y,
namely, part 9y2) and the residual part of the air-impermeable
sheet layer 19 (i.e., the part under the dotted lines that traverse
the air-impermeable sheet layer 19, namely, part 19y2). The
air-impermeable sheet layer 19 may be bonded onto the outer surface
of the nonwoven fabric 9y, and may appear also in parts of the
first side I. The air-impermeable sheet layer 19 may appear also in
a part(s) of the first side I, provided that it does not prevent
the release of water vapor from the first side I of the bag P.
[0074] In a structure for cooling according to another embodiment
of the invention, a water-retentive member may contain a bag and a
water-absorptive polymer, wherein the water absorptive polymer
adheres to or is fused to an inner surface(s) of at least one side
of the bag, or exists in at least one side of the bag.
[0075] FIG. 7 shows a sectional view of an example of a
water-retentive member 500 of a structure for cooling according to
another embodiment of the invention. The member 500 may contain a
bag 31 made of a nonwoven fabric and a water-absorptive polymer 11.
The water-absorptive polymer 11 may adhere to inner surfaces of
both sides I and II of the bag 31. Alternatively, the
water-absorptive polymer 11 may appear on an inner surface of only
one side (side I or side II) of the bag 31. Furthermore, the
water-absorptive polymer 11 may be mixed in a nonwoven fabric 31a
of the first side I and/or a nonwoven fabric 31b of the second side
II. Alternatively, the side I and/or II each may be made of two
sheets of nonwoven fabric, and a water-absorptive polymer may be
placed between the two sheets.
[0076] FIG. 8 shows a sectional view of another example of a
water-retentive member 600 of a structure for cooling according to
another embodiment of the invention. The water-retentive member 600
may contain a bag Q and a water-absorptive sheet 17 placed inside
the bag Q. Of the bag Q, one side I may be made of a nonwoven
fabric. The other side II may be made of a nonwoven fabric 33b, an
air-impermeable sheet layer 19, and a water-absorptive polymer 11.
The side II may be water impermeable and the polymer 11 may be
bonded or fused to the inner surface of the nonwoven fabric 33b.
The nonwoven fabric 33b may be partly or completely (preferably
completely) adhered to the air-impermeable sheet layer 19. The
adhesion may be achieved by fusing a polymer within the nonwoven
fabric 33b or within the air-impermeable sheet layer 19, or by
using an adhesive. The water-absorptive sheet 17 placed inside the
bag Q do not contain water-absorptive polymer, although a
water-absorptive sheet with a water-absorptive polymer may also be
used. Alternatively, both a water-absorptive sheet without
water-absorptive polymer and a water-absorptive sheet with a
water-absorptive polymer may be used together.
[0077] Each element that forms a part of a structure for cooling in
accordance with embodiments of the present invention are described
in the following section, together with examples.
[0078] The fibrous layer of the cover (see FIG. 3(1)) may be made
of at least one material selected from the group consisting of a
woven fabric, a nonwoven fabric, and a knit material, preferably a
woven fabric (a cloth) or a nonwoven fabric. If the fibrous layer
is made of a woven fabric, its raw material(s) may be selected from
the group consisting of cotton, rayon, polyester, polypropylene,
nylon, acrylic, and a combination thereof; and its thickness may be
about 60 to 150 g/m.sup.2, preferably 80 to 130 g/m.sup.2, and more
preferably 90 to 110 g/m.sup.2. For a fibrous layer used for the
first side a (an air-permeable side) of the cover, an ultra high
density woven fabric may be used instead of an usual woven fabric.
In particular, the ultra high density woven fabric made of ultra
microfiber in high density preferably has a moisture-permeability
of 2,000 to 3,000 g/m.sup.224 hours.
[0079] If the fibrous layer is made of a nonwoven fabric, its raw
material(s) may be selected from the group consisting of rayon,
nylon, polyester, acrylic, polypropylene, vinylon, polyethylene,
urethane, cotton, cellulose, and a combination thereof; and its
thickness may be bout 20 to 120 g/m.sup.2, preferably 30 to 100
g/m.sup.2, and more preferably 40 to 60 g/m.sup.2.
[0080] If the fibrous layer is made of a knit material, its raw
materials) may be selected from the group consisting of rayon,
polyester, polypropylene, nylon, acrylic, and a combination
thereof; and its thickness may be about 80 to 150 g/m.sup.2, and
preferably 90 to 120 g/m.sup.2.
[0081] The nonwoven fabric used for the fibrous layer may be, for
example, a melt-blown nonwoven fabric, a spun-bonded nonwoven
fabric, a spun-lace nonwoven fabric, or a spun-needle nonwoven
fabric. In accordance with embodiments of the present invention,
any suitable nonwoven fabric may be used.
[0082] The first side a (an air-permeable side) of the cover may
contain an outer fibrous layer and an inner air-permeable sheet
layer(see FIG. 3(1)). The two layers may be partly adhered to each
other. The air-permeable sheet may be a film or sheet made of a
polymer, through which air (also a water vapor) can pass. Examples
of such film or sheet include a moisture-permeable porous film,
e.g., an air-impermeable polymer film with air-permeable openings.
The polymer film per se may be water repellent or water proof. The
thickness of the moisture-permeable porous film used in the present
invention may be around 100 .mu.m or less, preferably 30 to 80
.mu.m, and more preferably 50 to 70 .mu.m.
[0083] A water proof, non-porous membrane through which water vapor
can pass, thus, air-permeable, is known. One example of such a
membrane is a polyester, moisture-permeable and water proof film
`Flecron` made by O. G. Film Co., Ltd. In accordance with
embodiments of the invention, such membranes may also be used as an
air-permeable sheet. Other examples of the polymer that may be used
as a raw material for the air-permeable sheet include polyetylene,
polypropylene, polyester, polyamide, poly(vinyl chloride),
poly(vinilydene chlorise), polyurethane, polystyrene,
ethylene-vinyl acetate copolymer, and polycarbonate. The
air-permeable sheet may be a mono-layered or a multi-layered
film.
[0084] The methods for preparing a porous film with an appropriate
moisture-permeability are known. For example, the
moisture-permeability of the first side a of the cover may be
controlled to be 500 to 3,000 g/m.sup.224 hours. This may be
accomplished by controlling the moisture-permeability of the porous
polymer film in the air-permeable sheet layer and by selecting an
appropriate condition to adhere the fibrous layer and the
air-permeable sheet layer together.
[0085] The second side b of the cover (see FIG. 3(2)) may be
water-permeable or water-impermeable. In the case of
water-permeable, the second side b may be made of a woven fabric, a
nonwoven fabric, or a knit material. If water-impermeable, the
second side b may be an air-impermeable sheet or an air-permeable
sheet but with low air-permeability, such as various water
repellent, polymeric resin films and sheets. Examples of the
air-impermeable sheet and an air-permeable sheet with low
air-permeability may include air-impermeable polymer sheets, such
as a polyethylene film. The thickness of the polymer sheet may be
about 100 .mu.m or less, preferably 20 to 90 .mu.m, more preferably
30 to 70 .mu.m, and still more preferably 40 to 60 .mu.m. Examples
of the polymer that may be used as a raw material for the
air-impermeable sheet or the air-permeable sheet with low
air-permeability may include polyethylene, polypropylene,
polyester, polyamide, poly(vinyl chloride), poly(vinilydene
chloride), polyurethane, polystyrene, ethylene-vinyl acetate
copolymer, and polycarbonate. Further, the air-impermeable sheet or
the air-permeable sheet with low air-permeability may be a
mono-layered or a multi-layered film. If the second side b is
water-impermeable, it is preferable that the second side b may have
a two-layered structure that contains an inner, air-impermeable
sheet or air-permeable sheet with low air-permeability (preferably
an air-impermeable sheet) and an outer fibrous layer. The fibrous
layer may be made of a material described above for the first side
a.
[0086] The first side I of the bag of the water-retentive member
(see FIG. 4) may be made of a moisture- or water-permeable
material. One example of the moisture- or water-permeable material
may be a fibrous material. Specific examples of the fibrous
material may be the same as those that have been described as the
materials for the fibrous layer of the cover. It is preferable that
the bag in the water-retentive member may be made of a nonwoven
fabric. If the nonwoven fabric is used, the thickness may be about
30 to 150 g/m.sup.2, preferably 40 to 120 g/m.sup.2, and more
preferably 50 to 70 g/m.sup.2.
[0087] The second side II of the bag of the water-retentive member
(see FIG. 4) may be water-permeable or water-impermeable. In the
case of water-permeable, the second side II may be made of raw
material such as a woven fabric, a nonwoven fabric, or a knit
material. In the case of water-impermeable, the second side II may
be an air-impermeable sheet or an air-permeable sheet with low
air-permeability, such as various water repellent, polymeric resin
films and sheets. The air-impermeable sheet and the air-permeable
sheet with low air-permeability may be the same as those that have
been described above. If the second side II is water-impermeable,
the second side II may preferably have a two-layered structure
containing a layer of an air-impermeable sheet or an air-permeable
sheet with low air-permeability (preferably an air-impermeable
sheet) and a fibrous layer. The fibrous layer may be the same as
one described above.
[0088] When the second side II has a two-layered structure in the
water-retentive member in a structure for cooling according to one
embodiment of the invention, the layer of an air-impermeable sheet
or an air-permeable sheet with low air-permeability may be placed
either inside or outside. Similarly, the fibrous layer may be
outside or inside. In a water-retentive member in a structure for
cooling according to one embodiment of the invention, if the
fibrous layer of the second side II comprises a water-absorptive
polymer, a layer of an air-impermeable sheet or an air-permeable
sheet with low air-permeability may be placed outside. If a fibrous
layer of the second side II contains no water-absorptive polymer, a
layer of an air-impermeable sheet or an air-permeable sheet with
low air-permeability may be placed outside or inside.
[0089] A water-absorptive material for use with embodiments of the
invention may have a water-absorptive property and/or a
water-holding property. In accordance with embodiments of the
present invention, preferred materials may include a
water-absorptive material with a sheet-like form, i.e., a
water-absorptive sheet. Examples of the water-absorptive material
may include sheet-like water-absorptive materials such as paper,
linear pulp, punched cotton, a nonwoven fabric with
water-absorptive or water-retentive property, a woven fabric, and a
porous sheet made of a synthetic resin; expanded synthetic resins
such as polyurethane foam, viscose foams, nylon foams, expanded
phenol resins, and expanded urea resins; sponge; absorptive cotton;
rayon cotton; a mat made of a palm shell fiber or an excelsior
fiber; and a blanket. Among them, a nonwoven fabric with
water-absorptive or water-retentive property, e.g., a spun-needle,
nonwoven fabric, is preferred because the nonwoven fabric may be
light and resistant to degradation, and may also have excellent
durability.
[0090] If a nonwoven fabric is used as the water-absorptive
material, its thickness may be around 30 to 150 g/m.sup.2,
preferably 50 to 120 g/m.sup.2, and more preferably 80 to 100
g/m.sup.2. The water-absorptive or water-retentive nonwoven fabric
may be made from a water-absorptive fiber or a mixture of a
water-absorptive fiber, and a water-retentive fiber. Examples of a
water-absorptive fiber may include a cross-linked acrylate fiber, a
surface-hydrolyzed acrylic fiber, a fiber made of a
polyester-(meth)acrylic acid graft copolymer, and a polyester
fiber. In addition to hydrophilic fibers such as rayon, examples of
the water-retentive fiber may also include a porous fiber, in which
water may be held in voids (pores) present inside the fiber.
[0091] If a woven fabric is used as a water-absorptive sheet, its
raw material may not be limited to those have water-absorptive or
water-retentive property. Examples of the raw material include
cotton, rayon, polyester, and acrylate. In the present invention,
it is preferable to use a water-absorptive sheet containing a
water-absorptive polymer. For example, the water-absorptive sheet
may contain a water-absorptive polymer, in the following exemplary
configurations: (1) a water-absorptive polymer bonded onto a
surface of a water-absorptive sheet; (2) a water-absorptive polymer
mixed in a water-absorptive sheet; and (3) a water-absorptive
polymer present between two water-absorptive sheets to form a
compound sheet. Note that these configurations are for
illustrations only. One skilled in the art would appreciate that
other configurations may also be used without departing from the
scope of the invention, such a combination of these exemplary
configurations.
[0092] FIG. 10 shows an example of the above configuration (2).
Part of the water-absorptive polymer 11 may be bonded onto a
surface of a water-absorptive support sheet 13.
[0093] In one embodiment of the invention, a water-retentive member
may contain a bag (preferably a bag made of a nonwoven fabric) that
has a water-absorptive polymer. In this case, the water-absorptive
polymer is present on an inner surface of the bag or in the
material of which the bag is made. Thus, the water-absorptive
polymer may be bonded onto a surface of a member (e.g., a nonwoven
fabric) of the bag or may be mixed within the materials of which
the bag is made, Alternatively, at least one side of the bag may be
made by placing the water-absorptive polymer between two
water-absorptive sheets.
[0094] Examples of water-absorptive polymers include polyacrylates
(e.g., copolymer of acrylic acid and a sodium salt of acrylic acid,
i.e., partial salt of poly(acrylic acid)), a copolymer of an
acrylic acid and vinyl alcohol, a cross-linked poly(sodium
acrylate), a graft copolymer of starch and acrylic acid, a
hydrolyte of a cross-linked graft copolymer of starch and acrylic
acid, a copolymer of isobutylene and maleic anhydride, a saponified
copolymer of isobutylene and maleic anhydride, poly(aspartic acid),
a cross-linked copolymer of acrylamide, a cross-linked copolymer of
acrylic acid (or an acrylate) and acrylamide, a cross-linked
poly(acrylic acid), a cross-linked polyacrylate, a cross-linked
copolymer of acrylic acid (or a salt of acrylic acid) and an
acrylic ester, a cross-linked polyvinyl alcohol denatured with a
carboxylic acid, a cross-linked N-vinyl compound, a cross-linked
poly(sulfonic acid), a cross-linked poly(sulfonate), a cross-linked
copolymer of acrylic acid (or an acrylate) and sulfonic acid (or a
sulfonate), a cross-linked poly((meth)acrylamide-N-alkyl
(C.sub.1-5) sulfonic acid (or a sulfonate)), a cross-linked
copolymer of a (meth)acrylamide-N-alkyl (C.sub.1-5) sulfonic acid
(or a sulfonate) and a (meth)acrylate, a cross-linked sulfonated
polyethylene, a cross-linked poval (trademark), a cross-linked
poly(meth)acrylamide, a cross-linked poly(ethylene oxide), a
cross-linked poly(vinylalcohol), and a cross-linked
carboxymethylcellulose. Water absorptive polymers may be preferred
because, for example, they may absorb a brine (0.9% salt
concentration) at the capacity of 70 to 150 times the weight of the
polymer (JIS K7223).
[0095] The methods of manufacturing a sheet (e.g., a nonwoven
fabric) that holds a water-absorptive polymer are not particularly
limited. Examples include the following: (1) a polymer may be
placed between two water-absorptive sheets, and the bonding between
them may be achieved by using, for example, a thermal treatment or
an adhesive; (2) a water-absorptive polymer may be scattered and
adhered onto the adhesive surface(s) of a water-absorptive sheet;
and (3) a nonwoven fabric may be prepared or a paper may be
prepared from a pulp in the presence of a water-absorptive
polymer.
[0096] Although the amount of the polymer is not limited, it may be
about 30 to 200 g/m.sup.2, preferably 50 to 150 g/m.sup.2, and more
preferably 70 to 100 g/m.sup.2.
[0097] The positions of the water-absorptive sheet with a
water-absorptive polymer inside the bag are not particularly
limited. In the case of plural layers of sheets, the
water-absorptive sheet with a water-absorptive polymer may be
preferably placed as a outermost layer that faces inner surface of
first side I (the outer surface of the side I faces an
air-permeable side of the cover) of the water-retentive member, or
as a second layer next to the outermost layer.
[0098] A water-retentive member used in a structure for cooling
according to embodiments the present invention may also include a
minus (negative) ions-emitting material. This material may be used
in the following fashion: (1) bonded onto the inner surface of the
bag of a water-retentive member, (2) bonded onto a surface of a
water-absorptive material, (3) mixed within a water-absorptive
material, or (4) placed between two water-absorptive materials.
Examples of the minus (negative) ions-emitting material include
tourmaline, weathered coral, minerals of rare earth elements,
amber, carbon black, thoron, and germanium.
[0099] In accordance with some embodiments of the present
invention, a water-retentive member or a water-absorptive polymer
may contain an antifungal agent. The kinds of the antifungal agents
are not limited. However, those agents that cause no or low
irritation are preferred.
[0100] Examples of preferred antifungal agents include triazole
derivatives such as
2-(4-chlorophenyl)-3-cyclopropyl-1-(1H-1,2,4-triazol-1-yl)-butan-2-ol,
carboxybenzotriazole, and
{1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazole)-1-yl}-butan-2-on;
pyrithione derivatives such as zinc or sodium salt of
2-pyridinethiol-1-oxide; benzimidazole derivatives such as
2-(4-thiazolyl)benzimidazole, 2-(carbomethoxyamino)benzimidazole,
2-benzimidazole methylcarbamate, 1-butylcarbamyl-2-benzimidazole
methylcarbamate, 6-benzoyl-2-benzimidazole methylcarbamate,
6-(2-thiophenecarbonyl)-2-benzimidazole methylcarbamate,
2-thiocyanomethylthiobenzimidazole,
1-dimethylaminosulfonyl-2-cyano-4-bromo-6-trifluoromethylbenzimidazole,
2-(2-chlorophenyl)benzimidazole,
2-{1-(3,5-dimethylpyrazolyl)}benzimidazole,
2-(2-furyl)benzimidazole, parbendazole,
5,6-dichloro-1-phenoxycarbonyl-2-trifluoromethylbenzimidazole, and
4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazole; benzthiazole
derivatives such as 2-(4-thiocyanomethyl-thio)benzthiazole, sodium
salt of 2-mercaptobenzthiazole, zinc salt of
2-mercaptobenz-thiazole, and
2-(thiocyanomethylsulfonyl)benzthiazole, isothiazoline derivatives
such as 2-(n-octyl)-4-isothiazolin-3-on, 1,2-benzisothiazolin-3-on,
5-chloro-2-methyl-4-isothiazolin-3-on,
2-methyl-4-isothiazolin-3-on, and
4,5-dichloro-2-cyclohexyl-4-isothiazolin-3-on; and thiabendazole
derivatives such as thiabendazole.
[0101] Among the preferred antifungal agents described above, at
least one member selected from the group consisting of triazole
derivatives, pyrithione derivatives, benzthiazole derivatives,
isothiazoline derivatives, and thiabendazole derivatives is
preferred. The triazole derivatives are more preferred. The
antifungal agents may be adhered to the surface(s) of a
water-retentive member, mixed within a water-retentive member,
adhered to the surfaces of the particles of water-absorptive
polymers, or mixed within water-absorptive polymers. The amounts of
the antifungal agents may be preferably 0.1 to 40 g/m.sup.2 of the
area of the water-retentive member, more preferably 2 to 20
g/m.sup.2, still more preferably 4 to 10 g/m.sup.2, and extremely
preferably 6 to 8 g/m.sup.2. The amounts of the antifungal agents
may be preferably 0.001 to 5% by weight of the water-absorptive
polymers, more preferably 0.01 to 3% by weight, still more
preferably 0.1 to 1% by weight.
[0102] Methods for bonding antifungal agents to a water-retentive
member or a water-absorptive polymer are not restricted. The
methods for mixing the antifungal agents within a water-retentive
member or a water-absorptive polymer are likewise not restricted.
Preferred methods include the following: (1) when a air-permeable
sheet is prepared, the antifungal agents may be mixed with other
raw materials; (2) when the particles of the water-absorptive
polymers are prepared, the antifungal agents may be mixed with
other raw materials; (3) the air-permeable sheets or the particles
of the water-absorptive polymers may be first immersed in a
solution containing a antifungal agent and then dried; (4) a
surface of an air-permeable sheet may be printed with a liquid
containing an antifungal agent and a binder; (5) a liquid
containing an antifungal agent and a binder may be applied onto a
surface of an air-permeable sheet; (6) a liquid containing an
antifungal agent (and a binder, if necessary) may be first sprayed
onto a water-retentive member, a air-permeable sheet or the
particles of a water-absorptive polymer, and then dried. It is
preferable to use a liquid containing an antifungal agent and a
binder to adhere the antifungal agent to a water-retentive member.
The liquid may be a solution or an emulsion. The binder may be a
monomer, a polymer, or a resin. If the monomer, preferably a
self-polymerizing or self-cross-linking type, is used, it may be
polymerized or cross-linked during a drying or heating process. A
polymer prepared from a self-polymerizing or self-cross-linking
monomer may be tightly bound to a water-retentive member with an
antifungal agent
[0103] Examples of a water-soluble or dispersible polymer or resin
as the binder may include polyvinyl alcohol; cellulose compounds
such as those prepared by chemically treating a natural cellulose,
e.g., a sulfated, phosphorylated, nitrated, carboxymethylated,
carboxypropylated, or hydroxyethylated cellulose; starch
derivatives such as phosphorylated starch, methyl starch,
carboxymethyl starch, and hydroxyethyl starch; vinyl acetate
derivatives such as poly(vinyl acetate), vinyl acetate-maleate
copolymers, and vinyl acetate-acrylic copolymers. Examples of an
organic solvent-soluble or dispersible polymer or resin as the
binder may include urethane polymers, styrene-butadiene polymers,
and acrylic polymers.
[0104] Examples of a self-polymerizing or self-cross-linking
monomer type binder may include an acrylic one for a solution
polymerization containing an acrylic monomer and an initiator; and
those for emulsion polymerization such as a solvent and wear
resistance acrylic emulsion, a weather proof acrylic-silicone
emulsion, a colloid-stable, fine-grain acrylic-silicone emulsion, a
one-component, cold-cross-linking acrylic emulsion, an
alkali-setting, cationic, fine-grain acrylic-silicone emulsion, and
a hybrid acrylic epoxy emulsion.
[0105] The concentration of an antifungal agent in a liquid may be
preferably 0.1 to 50% by weight, more preferably 1 to 40% by
weight, and still more preferably 2 to 30% by weight. The
concentration of a binder (i.e., a monomer, a polymer, or a resin)
in a liquid may be preferably 2 to 30% by weight, more preferably 4
to 20% by weight, and still more preferably 6 to 15% by weight.
[0106] Examples of processes for making a structure for cooling in
accordance with embodiments of the present invention are as
follows.
[0107] The cover may be made as follows:
[0108] A composite material for the first side a (an air-permeable
side) of the cover may be prepared by partially adhering an
air-permeable polymer film to one surface of a woven or nonwoven
fabric using any known method. Another composite material for the
second side b (a water-impermeable side) of the cover may be
prepared by partially or completely adhering an air-impermeable
polymer film with one surface of a woven or nonwoven fabric using
any known method. A composite material for the air-permeable side a
and a composite material for the water-impermeable side b may be
placed so that the air-permeable polymer film faces the
air-impermeable polymer film. The peripheries may be subsequently
sewn so as to form a bag. A means for opening and closing such as
fasteners may be installed on the bag.
[0109] Water-retentive members used in embodiments of the
invention, such as the water-retentive members 200 and 300 shown in
FIGS. 4 and 5, may be made as follows:
[0110] First, place a water-absorptive sheet(s) (e.g., FIG. 4 shows
a water-absorptive sheet 15 with a water-absorptive polymer; and
FIG. 5 shows a water-absorptive sheet 15 with a water-absorptive
polymer and a second water-absorptive sheet 17 without a
water-absorptive polymer) on a nonwoven fabric. Second, the
water-absorptive sheet(s) may be covered by another nonwoven
fabric. Finally, the peripheries may be adhered, fused, or
sewed.
[0111] Among the water-retentive members used in embodiments of the
invention, the member 700 shown in FIG. 9 may be made as
follows:
[0112] A composite material may be prepared by completely adhering
an air-impermeable polymer film onto one surface of a nonwoven
fabric using any known method. The water-absorptive sheets (e.g., a
water-absorptive sheet 15 with a water-absorptive polymer and a
water-absorptive sheet 17 without a water-absorptive polymer) may
then be placed on a nonwoven fabric 9y of the composite material.
Both ends of the composite material may be folded down to place the
edges of the composite material above the both ends of the
water-absorptive sheets. A nonwoven fabric 9x may be placed above
the outermost water-absorptive sheet to cover the sheet. The edges
of the nonwoven fabric 9x may be adhered to both edges of the
composite material (i.e., the edge of a part 9y1 and the edge of
another part 9y3).
[0113] One example of the water retentive members used in some
embodiments of the invention may be prepared as follows:
[0114] A water-absorptive polymer may be adhered to a rectangular
(or other shape) nonwoven fabric. Briefly, a nonwoven fabric may be
folded into a rectangular form, one half of which may have the
water-absorptive polymer present inside. On the three sides of the
rectangular form (other than the folded side), two sheets of a
nonwoven fabric are adhered or fused to each other to form a bag. A
water-absorptive sheet(s) may be placed on one half area of a
surface of a nonwoven fabric where water-absorptive polymers are
adhered. The bag with a rectangular form and a size of one half may
be made by folding and adhering the nonwoven fabric.
[0115] One example of a method of using a structure for cooling in
accordance with one embodiment the present invention is as
follows:
[0116] First, open the fastener of the cover. Second, place the
water-retentive member on the second side b (water impermeable
side) of the cover. Third, add water to the water-retentive member
through the first side I of a moisture- or water-permeable
material. For example, water may be poured onto the water-retentive
member using a kettle. Then, close the fastener.
[0117] If the second side II of the bag of the water-retentive
member is water-impermeable, the water-retentive member may be
taken out of the cover. Water may then be poured onto the member
before placing the member back into the cover. The amount of water
needed to fill the water-retentive member is not limited, insofar
as it is within the water-holding capacity of water-absorptive
polymer and other water-absorptive materials. For example, the
amount of water may be such that the water-retentive member has a
weight of about 300 to 15,000 g/m.sup.2, preferably 500 to 10,000
g/m.sup.2, more preferably 1,000 to 7,000 g/m.sup.2, and
specifically preferably 2,000 to 5,000 g/m.sup.2. The water may be
supplied to a part of the water-retentive member.
[0118] It is preferred to add a preservative, an antiseptics, or an
antifungal agent to the water inside the water-retentive member.
Examples of preservatives, antiseptics, and antifungal agents may
include thiabendazole compounds, organophosphoric acid compounds,
phenyphenol compounds, isothiazole compounds, benzalkonium
chloride, benzethonium chloride, alkyldiaminoethylglycine
hydrochloride, chlorohexydine gluconate, and sodium hypochlorite.
The preservatives, the antiseptics, or the antifungal agents may be
used at a concentration of about 0.0001 to 0.1% (weight/volume) and
preferably 0.01 to 0.1% (weight/volume).
EXAMPLES
[0119] Hereafter embodiments of the present invention are
illustrated using the following examples.
Example 1
(1) Preparation of Pads
[0120] The pads shown in FIG. 9 may be prepared, for example, by
using the following materials:
[0121] A. Materials Used for Each Layer [0122] A-1. Fibrous layers
1 and 7 of a cover 100: a board made of polyester (65%) and cotton
(35%); yarn finenesses of 45 counts.times.45 counts with density of
100.times.70. [0123] A-2. Air-permeable sheet layer 3 of a cover
100: porous polyethylene film with thickness of 50 .mu.m. [0124]
A-3. Air-impermeable sheet layer 5 of a cover 100: polyethylene
film; thickness of 50 .mu.m. [0125] A-4. Nonwoven fabric 9x of a
bag P of a water-retentive member 700; a lid portion: spun-bonded
nonwoven fabric made of a polyester with thickness of 40 g/m.sup.2.
[0126] A-5. Nonwoven fabric 9y of a bag P of a water-retentive
member 700; a bottom portion and side portions: spun-bonded
nonwoven fabric made of a polypropylene with thickness of 40
g/m.sup.2. [0127] A-6. Air-impermeable sheet layer 19 of a bag P of
a water-retentive member 700: polyethylene film with thickness of
40 .mu.m. [0128] A-7. Water-absorptive sheets 13 and 17:
spun-needle nonwoven fabric made of polyester (50%) and rayon (50%)
with thickness of 100 g/m.sup.2. [0129] A-8. Water-absorptive
polymer 11: cross-linked copolymer of isobutylene and maleic
anhydride sodium salt (manufactured by Kurare); absorbable amount
of brine: 100 times the weight of the polymer 11; amount of the
polymer 11 that are adhered to the water-absorptive sheet: 70
g/m.sup.2
[0130] B. Method for Preparation
B-1. Cover 100
[0131] (i) Five kinds of composite materials a are prepared by
partially adhering a porous polyethylene film 3 to a board 1 of
polyester (65%) and cotton (35%) using an adhesive. The adhesion
areas are controlled so that the composite materials are expected
to have moisture-permeability of about 500 g/m.sup.224 hours, about
700 g/m.sup.224 hours, about 1,000 g/m.sup.224 hours, about 1,200
g/m.sup.224 hours, or about 1,500 g/m.sup.224 hours, as determined
by the Lyssy method. After preparation, the actual
moisture-permeabilities of the five composite materials are
determined by the Lyssy method. The results are 492 g/m.sup.224
hours (about 500 g/m.sup.224 hours), 708 g/m.sup.224 hours (about
700 g m.sup.224 hours), 1,015 g/m.sup.224 hours (about 1,000
g/m.sup.224 hours), 1,263 g/m.sup.224 hours (about 1,200
g/m.sup.224 hours), and 1,528 g/m.sup.224 hours (about 1,500
g/m.sup.224 hours).
[0132] (ii) A composite material b is prepared by completely
adhering a polyethylene film 5 to a board 1 of polyester (65%) and
cotton (35%) 7 using an adhesive.
[0133] (iii) The composite materials a and the composite material b
are placed so that the porous polyethylene film 3 faces the
polyethylene film 5. Then, one side of the rectangle is sewed. A
fastener F is sewed to the remaining three sides to make a bag that
can be opened and closed by the fastener F. The size of the bag is
about 20 cm.times.30 cm.
B-2. Water-Retentive Member 700
[0134] (i) Referring to FIG. 9, a composite material c is prepared
by completely adhering a polyethylene film 19 (having sections
19y1, 19y2, and 19y3) onto one surface of a spun-bonded nonwoven
fabric 9y (having sections 9y1, 9y2, and 9y3) made of a
polypropylene using an adhesive.
[0135] (ii) A water-absorptive sheet 15 (comprising
water-absorptive polymers 11 adhered to a spun-needle nonwoven
fabric 13) is placed on the surface of a nonwoven fabric 9y of the
composite material c. A spun-needle nonwoven fabric 17 is then
placed on the water-absorptive sheet 15 (see FIG. 9).
[0136] (iii) Ends of the composite material c are folded to place
the edges of the composite material c above the ends of the
spun-needle nonwoven fabric 17.
[0137] (iv) A spun-bonded nonwoven fabric 9x made of a polyester is
placed above the spun-needle nonwoven fabric 17. The edges of the
nonwoven fabric 9x may be adhered to both edges of the composite
material c (i.e., the edges of the nonwoven fabrics 9y1 and 9y3).
On this side and far side, the nonwoven fabric 9x and the nonwoven
fabrics 9y1 and 9y3 of the composite material c are adhered to the
nonwoven fabric 9y2 of the composite material c.
B-3. Preparation of Test Samples (Pads)
[0138] A water-retentive member 700 is placed on the side b of the
cover 100, and then water is poured into the water-retentive member
700 through the nonwoven fabric 9x. The water-retentive member 700
holds water to a weight of 3.5 kg/m.sup.2. The fastener is then
closed.
(2) Determination of Surface Temperatures
[0139] The test samples are left in a thermostatic chamber of about
33 degrees Celsius, and their surface temperatures are determined
at appropriate time intervals. The results from these tests are
shown in FIG. 11.
[0140] FIG. 11 clearly shows that the surface temperatures of the
pads decrease with time. Pads having covers with higher
moisture-permeability show greater decreases of temperature. In the
pad having a moisture-permeability of about 500 g/m.sup.224 hours,
the surface temperature barely decreases.
Example 2
(1) Preparation of Pads
[0141] Similar to Example 1, three kinds of pads are prepared
having a size of 100 cm.times.200 cm. For the air-permeable side of
the cover, composite materials a having moisture-permeability of
about 1,000 g/m.sup.224 hours, about 1,200 g/m.sup.224 hours, and
about 1,500 g/m.sup.224 hours by the Lyssy method are used. The
amount of the water poured into the pads is 7 kg per pad (i.e., 3.5
kg/m.sup.2 of the water-retentive member).
(2) Organoleptic Test
[0142] A futon (which is like a mattress) is positioned inside a
room, in which the temperature is set at 30 degrees Celsius. The
pad is laid on the futon and covered with a sheet made of a cotton.
As a control, a futon without the pad is prepared.
[0143] The surface temperatures on the sheet are determined by
using a surface thermometer. Each panelist lies on the sheet and
judged at appropriate time intervals whether he(she) feels cool or
warm at neck, shoulders, loin, hip, legs/feet, and arms. The
results from these tests are shown in FIG. 12.
[0144] FIG. 12 clearly shows that when a pad is not used (control),
five minutes after the start of the test, the panelists feel warm
at three portions, i.e., neck, shoulders, and loin. At ten minutes
after the start of the test, the panelists feel warm at five
portions including portions (areas) other than arms. At forty
minutes after the start of the test, the panelists feel warm at all
judged portions. On the other hand, when the pads of the present
invention are used, the panelists feel cooler with time. Therefore,
when a pad of the present invention is used, an appropriate cooling
sensation can be felt. A person may thus sleep comfortably even
when the ambient temperature is high.
Example 3
(1) Preparation of Pads Containing Antifungal Agent
[0145] One pad is prepared in the same manner as described in
Example 1, except that the cover 100 has a size of 95 cm.times.185
cm. The water-retentive member 700 has a size of 90 cm.times.180 cm
containing an antifungal agent. The air-permeable side of the cover
has a moisture-permeability of about 1,000 g/m.sup.224 hours.
(2) Preparation of Liquid Containing an Antifungal Agent and
Binder
[0146] Table 1 shows the formulation of a solution containing an
antifungal agent. The solution is prepared by mixing the raw
materials.
TABLE-US-00001 TABLE 1 Amounts Raw Materials (% by weight) Amorden
NBP8 (Triazole Derivative from Yamato 2 Chemical Industrial Co.,
Ltd.) Aqueous Binder of Vinyl Acetate Derivative 1 Water 97 Total
100
(3) Adhesion of Antifungal Agent
[0147] From about 1 meter above the nonwoven fabric 9x of the bag
P, the solution shown in Table 1 is uniformly sprayed on the
water-retentive member 700. The amount of the solution used is
about 500 g. Namely, to the water-retentive member 700 having a
size of 90 cm.times.180 cm, 10 g of the antifungal agent are given.
Then, the water-retentive member 700 is left to dry under the
ambient conditions. Cooling structures with antifungal agents are
expected to last longer and may be reused without fungal or mold
growth.
[0148] Embodiments of the invention may include one or more of the
following advantages. Structures for cooling in accordance with
embodiments of the present invention may be repeatedly used for a
long time. It is of light weight and portable because the structure
may not contain water before its use. Further, these structures may
be easily folded for convenient transportation. The structures for
cooling may be used for sleep comfort in the summer. By controlling
moisture permeability of the cover, the cooling efficiency may then
be controlled. For example, having the structure's cover with a
large moisture permeability and the use of large amount of water or
refrigerated water, a large cooling effect may be achieved.
Furthermore, the structures may be adjusted to hold water in
portions of a cooling structure to cool certain parts of body
(e.g., shoulder or back). That is, water may be added and held at
only part(s) of the water-retentive member corresponding to part(s)
of human body that need to be cooled. Thus, the structures may be
suitable for cooling in the field of medical care. For example, the
structures for cooling according to embodiments of the invention
having water-absorptive material may be used as a cushion suitable
for bed pads. Furthermore, the structures for cooling in accordance
with embodiments of the present invention may contain antifungal
agents to eliminate or minimize the problem of mold
contamination.
[0149] While the invention has been described with respect to a
limited number of embodiments, those skilled in the art, having
benefit of this disclosure, will appreciate that other embodiments
can be devised which do not depart from the scope of the invention
as disclosed herein. Accordingly, the scope of the invention should
be limited only by the attached claims.
* * * * *
References