U.S. patent application number 16/303061 was filed with the patent office on 2019-07-04 for hydrophobic fiber and manufacturing method thereof.
This patent application is currently assigned to KB TSUZUKI K.K.. The applicant listed for this patent is KB TSUZUKI K.K.. Invention is credited to Atsushi HIROSUE, Hiroshi MIYAMOTO, Motohisa NOMA.
Application Number | 20190203411 16/303061 |
Document ID | / |
Family ID | 60325856 |
Filed Date | 2019-07-04 |
United States Patent
Application |
20190203411 |
Kind Code |
A1 |
MIYAMOTO; Hiroshi ; et
al. |
July 4, 2019 |
HYDROPHOBIC FIBER AND MANUFACTURING METHOD THEREOF
Abstract
A hydrophobic fiber is provided which, obtained by modifying a
natural fiber-containing fiber material without the use of fluorine
compounds, has improved quick-dry properties, durability,
wash-and-wear properties and antifouling properties while
sufficiently maintaining the moisture absorption and desorption of
the natural fibers; a manufacturing method of said fiber is also
provided. By fixing a silicone elastomer film to at least part of
the surface of a fiber material that contains cellulose fibers
and/or animal fibers, the fiber is made into a hydrophobic fiber
with a surface tension of less than 72 mN/m. The silicone elastomer
film comprises methylhydrogen polysiloxane cross-linked with zinc
stearate as the crosslinking agent.
Inventors: |
MIYAMOTO; Hiroshi;
(Kasugai-shi, Aichi-ken, JP) ; NOMA; Motohisa;
(Imabari-shi, Ehime-ken, JP) ; HIROSUE; Atsushi;
(Setouchi-shi, Okayama-ken, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KB TSUZUKI K.K. |
Nagoya-shi, Aichi |
|
JP |
|
|
Assignee: |
KB TSUZUKI K.K.
Nagoya-shi, Aichi
JP
|
Family ID: |
60325856 |
Appl. No.: |
16/303061 |
Filed: |
May 20, 2016 |
PCT Filed: |
May 20, 2016 |
PCT NO: |
PCT/JP2016/065004 |
371 Date: |
November 19, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D06M 13/188 20130101;
D06M 2101/06 20130101; D06M 2200/12 20130101; D06M 11/44 20130101;
D06M 10/10 20130101; D06M 15/643 20130101; D06M 23/08 20130101;
D06M 2200/11 20130101 |
International
Class: |
D06M 15/643 20060101
D06M015/643; D06M 10/10 20060101 D06M010/10; D06M 13/188 20060101
D06M013/188 |
Claims
1. A hydrophobic fiber which is rendered hydrophobic by modifying a
fiber material containing at least one of a cellulose fiber or an
animal fiber; the hydrophobic fiber being characterized in that a
silicone elastomer film having methylhydrogen polysiloxane
crosslinked with zinc stearate as a crosslinking agent is affixed
to at least a portion of a surface of the fiber material, the
hydrophobic fiber having a surface tension of less than 72
mN/m.
2. The hydrophobic fiber according to claim 1, wherein the silicone
elastomer film contains conductive fine particles made of an n-type
semiconductor containing zinc oxide as a principal component.
3. A hydrophobic fiber manufacturing method for obtaining a
hydrophobic fiber by modifying a fiber material containing at least
one of a cellulose fiber or an animal fiber, comprising the steps
of: immersing at least a portion of the fiber material in a mixed
solution obtained by mixing zinc stearate into an aqueous
dispersion in which silicone elastomer particles containing
methylhydrogen polysiloxane as a principal component are dispersed;
and obtaining the hydrophobic fiber having a surface tension of
less than 72 mN/m by affixing a film shaped silicone elastomer in
which the particles are crosslinked using the zinc stearate as a
crosslinking agent to at least a portion of a surface of the fiber
material.
4. The hydrophobic fiber manufacturing method according to claim 3,
further comprising the steps of adding and causing to be contained
in the mixed solution conductive fine particles made of an n-type
semiconductor containing zinc oxide as a principal component, and
obtaining the hydrophobic fiber having the conductive fine
particles supported on the surface thereof.
Description
TECHNICAL FIELD
[0001] The present invention relates to a hydrophobic fiber, which
is obtained by modifying a natural fiber including at least one of
a cellulose fiber or an animal fiber to render it hydrophobic, as
well as to a manufacturing method for producing the same.
BACKGROUND ART
[0002] In general, a fiber obtained from a natural material such as
a cellulose fiber or an animal fiber (hereinafter also referred to
as a natural fiber) has an excellent moisture absorption/desorption
property in comparison with synthetic fibers. However, because
natural fibers absorb water and swell, they are inferior in terms
of their rapid drying ability, durability, and shape stability
(wash-and-wear ability), etc., after being washed. Further, natural
fibers have a drawback in that they are inferior to synthetic
fibers even in terms of their stain resistance (antifouling
ability) with respect to oil stains.
[0003] Thus, in relation to a natural fiber, there is a desire to
improve the physical properties thereof such as a rapid drying
ability and durability, by modifying the natural fiber without
impairing its intrinsic moisture absorption/desorption property.
For example, in Japanese Laid-Open Patent Publication No.
08-134780, it is proposed to impart a water and oil repellent
property to wool in a natural fiber. More specifically, a water
repellent and oil repellent coating film is formed by applying in
this order through adsorption a polysiloxane-based resin such as
dimethylpolysiloxane or the like, and a fluorine compound such as a
polytetrafluoroethylene resin or the like with respect to a wool
fiber on which an oxidation treatment was performed.
SUMMARY OF INVENTION
[0004] However, in this case, since a sufficient bonding force
between the wool fiber and the coating film cannot be obtained, and
the coating film tends to fall off easily due to washing or the
like, it is difficult to obtain a water and oil repellent property
that exhibits sufficient washing durability. Further, when a
fluorine compound is used, the moisture absorption/desorption
property of the wool fiber tends to be lowered, and therefore,
there is a concern that a feeling of stuffiness or mugginess or the
like may occur when the wool fiber is worn. Furthermore, in
consideration of their influence on the environment and the like,
from the standpoint of further enhancing safety, it is preferable
to avoid the use of fluorine compounds.
[0005] The present invention has been devised taking into
consideration the aforementioned problems, and has the object of
providing a hydrophobic fiber and a manufacturing method for
producing the same, in which, by modifying a fiber material
containing a natural fiber without using a fluorine compound, a
rapid drying ability, durability, a wash-and-wear ability, and an
antifouling ability thereof are improved while maintaining a
sufficient moisture absorption/desorption property of the natural
fiber.
[0006] In order to achieve the above-described object, the present
invention is a hydrophobic fiber, which is rendered hydrophobic by
modifying a fiber material containing at least one of a cellulose
fiber or an animal fiber, the hydrophobic fiber being characterized
in that a silicone elastomer film having methylhydrogen
polysiloxane crosslinked with zinc stearate as a crosslinking agent
is affixed to at least a portion of a surface of the fiber
material, the hydrophobic fiber having a surface tension of less
than 72 mN/m.
[0007] In the hydrophobic fiber according to the present invention,
the silicone elastomer film is affixed to at least a portion of the
surface of a fiber material containing a natural fiber including at
least one of a cellulose fiber or an animal fiber (hereinafter
referred to simply as a natural fiber). Consequently, the surface
tension of the hydrophobic fiber is less than 72 mN/m, or in other
words, is smaller than the surface tension of water. By providing
the silicone elastomer film in this manner, the fiber material can
be rendered hydrophobic without the use of a fluorine compound, and
therefore, it is possible to prevent a decrease in the intrinsic
moisture absorption/desorption property of the natural fiber.
[0008] Further, as described above, the hydrophobic fiber is
rendered hydrophobic due to the silicone elastomer film, whereby it
is possible to suppress swelling due to absorption of water during
washing with water or the like, which is known to be a defect of
natural fibers, and therefore, the rapid drying ability,
durability, wash-and-wear ability, etc., can be improved. Further,
by being brought close to the surface tension of sebaceous oil and
cooking oil, which are likely to be a cause of oil stains in
everyday life, the hydrophobic fiber exhibits an oil repellent
property, and therefore, it is unlikely for oil stains to become
adhered thereto, and the antifouling ability can also be
improved.
[0009] Furthermore, since the silicone elastomer film can freely
expand and contract in following relation with deformation of the
fiber material, it is possible to maintain the state in which the
silicone elastomer film is firmly affixed to the surface of the
fiber material. Consequently, even in the event that frictional
forces or the like are applied to the hydrophobic fiber in water or
in a chemical cleaning agent when washing or dyeing is performed,
it is possible to prevent the silicone elastomer film from peeling
off from the surface of the natural fiber, and the silicone
elastomer film itself is superior in terms of its durability.
[0010] As described above, the hydrophobic fiber is capable of
improving a rapid drying ability, durability, a wash-and-wear
ability, and an antifouling ability, etc., while also providing a
moisture adsorption/desorption property superior to that of the
original natural fiber, and in addition, is capable of maintaining
the state in which such physical properties are enhanced over a
prolonged period. Hence, compared to an untreated natural fiber,
the amount of water used during washing of the hydrophobic fiber
with water can be reduced, which is also preferable from the
standpoint of the environment.
[0011] Further, the above-described silicone elastomer film is
affixed to the fiber material mainly by a mechanical action such as
an anchor effect or the like. Stated otherwise, the majority of the
functional groups in the natural fiber exist in a state in which
chemical bonds such as covalent bonding are not formed with the
silicone elastomer film. Therefore, when the hydrophobic fiber is
dyed, the functional groups in the natural fiber and the dye are
capable of reacting sufficiently with each other, and dying with
the dye can be performed suitably while avoiding color unevenness.
Stated otherwise, the hydrophobic fiber is excellent in terms of
its ability to be dyed, and piece dyeing thereof can be performed
easily.
[0012] In the above-described hydrophobic fiber, the silicone
elastomer film preferably contains conductive fine particles made
of an n-type semiconductor containing zinc oxide as a principal
component. The conductive fine particles absorb ultraviolet rays
and both absorb and reflect infrared rays. On the other hand, the
conductive fine particles transmit visible light. Accordingly, by
the conductive fine particles being contained within the silicone
elastomer film, it is possible for an ultraviolet shielding
function and an infrared shielding function to be added to the
hydrophobic fiber without inhibiting the development of color
therein. In addition, since conductivity can be suitably added to
the hydrophobic fiber, electrostatic charging is prevented, and
generation of static electricity can effectively be avoided.
Furthermore, excellent deodorizing and antibacterial properties can
be added.
[0013] Further, generally, a wearer of clothing tends to experience
a feeling of irritation from the clothing due to static electricity
generated on the surface or the like of the clothing acting on the
open pores, or by coming into contact with a fiber that possesses
low flexibility. On the other hand, the conductive fine particles
which mainly contain zinc oxide possess an astringent action.
Accordingly, it is possible to suppress opening of the pores of a
wearer of clothing or the like made from a hydrophobic fiber
containing the conductive fine particles. Furthermore, in such a
hydrophobic fiber, as described above, in addition to preventing
the generation of static electricity due to the conductive fine
particles, the hydrophobic fiber exhibits excellent flexibility due
to the presence of the silicone elastomer film. Combined with this
aforementioned feature, it is possible to reduce irritation to the
wearer.
[0014] Further still, in the hydrophobic fiber, the conductive fine
particles are contained within the silicone elastomer film which is
firmly affixed to the fiber material in the manner described above.
Consequently, since the conductive fine particles are firmly
supported on the surface of the fiber material, the aforementioned
functions that are added by the conductive fine particles are
prevented from being reduced due to washing or the like of the
hydrophobic fiber, and the sustainability of such functions is
superior.
[0015] Further, the present invention is characterized by a
hydrophobic fiber manufacturing method for obtaining a hydrophobic
fiber by modifying a fiber material containing at least one of a
cellulose fiber or an animal fiber, comprising the steps of
immersing at least a portion of the fiber material in a mixed
solution obtained by mixing zinc stearate into an aqueous
dispersion in which silicone elastomer particles containing
methylhydrogen polysiloxane as a principal component are dispersed,
and obtaining the hydrophobic fiber having a surface tension of
less than 72 mN/m by affixing a film shaped silicone elastomer in
which the particles are crosslinked using the zinc stearate as a
crosslinking agent to at least a portion of a surface of the fiber
material.
[0016] Through the process steps described above, it is possible to
obtain the hydrophobic fiber by firmly affixing the silicone
elastomer film to the surface of the natural fiber. Due to such a
silicone elastomer film, the surface tension of the fiber material
can be made less than the surface tension of water, and the fiber
material can be rendered hydrophobic without using a fluorine
compound. Therefore, swelling of the natural fiber can be
suppressed without impairing the excellent absorption/desorption
property of the natural fiber, and thus the rapid drying ability,
durability, wash-and-wear ability, etc., can be improved. Further,
since the surface tension of the fiber material can be brought
close to the surface tension of sebaceous oil and cooking oil, and
an oil repellent property can be imparted to the hydrophobic fiber,
it is unlikely for oil stains to become adhered thereto, and the
antifouling ability can also be improved. Furthermore, due to its
elasticity, since the silicone elastomer film can freely expand and
contract in following relation with deformation of the natural
fiber, it is possible to maintain the state in which the silicone
elastomer film is firmly affixed to the surface of the natural
fiber. Consequently, it is possible to maintain the state in which
the rapid drying ability, durability, wash-and-wear ability, and
the antifouling ability, etc., are enhanced over a prolonged
period.
[0017] In the above-described hydrophobic fiber manufacturing
method, there are preferably further included the steps of adding
and causing to be contained in the mixed solution conductive fine
particles made of an n-type semiconductor containing zinc oxide as
a principal component, and obtaining the hydrophobic fiber having
the conductive fine particles supported on the surface thereof. Due
to the conductive fine particles, without inhibiting the
development of color in the hydrophobic fiber, it is possible to
obtain a hydrophobic fiber having an ultraviolet ray shielding
function and an infrared shielding function. Furthermore, the
hydrophobic fiber exhibits excellent deodorizing and antibacterial
properties. Further, it is possible to prevent the generation of
static electricity by preventing electrostatic charging, and due to
the astringent action, it is possible to suppress the opening of
pores of a wearer of clothing or the like made from the hydrophobic
fiber. In addition, since the hydrophobic fiber exhibits excellent
flexibility, in accordance with this feature, it is possible to
reduce irritation to the wearer. The above-described functions
which are added by the conductive fine particles are also superior
in terms of their ability to be sustained. This is because the
conductive fine particles are firmly supported on the surface of
the fiber material by being contained within the silicone elastomer
film.
[0018] In the hydrophobic fiber of the present invention, by
affixing the silicone elastomer film having methylhydrogen
polysiloxane crosslinked with zinc stearate as a crosslinking agent
to the surface of the fiber material, the surface tension of the
hydrophobic fiber becomes less than 72 mN/m. More specifically,
since the natural fiber can be rendered hydrophobic without using a
fluorine compound, swelling of the natural fiber can be suppressed
without impairing the excellent absorption/desorption property of
the natural fiber, and thus, the rapid drying ability, durability,
wash-and-wear ability, etc., can be improved. Further, since an oil
repellent property can be imparted by bringing the surface tension
of the fiber material close to the surface tension of sebaceous oil
and cooking oil, it is unlikely for oil stains to become adhered
thereto, and the antifouling ability can also be improved.
[0019] Furthermore, due to its elasticity, since the silicone
elastomer film can freely expand and contract in following relation
with deformation of the natural fiber, it is possible to maintain
the state in which the silicone elastomer film is firmly affixed to
the surface of the natural fiber. Consequently, it is possible to
maintain the state in which the rapid drying ability, durability,
wash-and-wear ability, and the antifouling ability, etc., are
enhanced over a prolonged period.
DESCRIPTION OF EMBODIMENTS
[0020] A preferred embodiment of a hydrophobic fiber according to
the present invention will be presented and described in detail
below in relation to a manufacturing method for manufacturing the
same.
[0021] The hydrophobic fiber according to the present invention is
obtained by modifying a fiber material containing a natural fiber
including at least one of a cellulose fiber or an animal fiber.
More specifically, the natural fiber may contain only a cellulose
fiber, only an animal fiber, or both of a cellulose fiber and a
natural fiber. In addition to the aforementioned natural fiber, a
synthetic fiber may be contained in the fiber material.
[0022] The form of the fiber material is not particularly limited,
and examples thereof may include cotton ball, tow, filaments,
slivers, yarn, a non-woven fabric, a woven fabric, a knitted
fabric, a towel, or the like.
[0023] As representative cellulose fibers, there may be cited
cotton which is a natural plant fiber. Further, the cellulose
fibers may also be hemp fibers such as ramie, linen, hemp, jute,
manila hemp, sisal hemp, or the like. Further, the cellulose fiber
may be composed of a so-called regenerated fiber obtained by
dissolving natural cellulose in a predetermined solvent and then
molding it into a fibrous form. Specific examples of this type of
regenerated fiber include rayon, polynosic, cupra, and Tencel
(registered trademark of Lenzing AG, Austria).
[0024] On the other hand, as representative examples of animal
fibers, there may be cited silk, wool, or animal hair fibers.
Specific examples of animal hair fibers include alpaca, mohair,
angora, cashmere, camel, vicugna, and the like.
[0025] As examples of synthetic fibers, there may be cited
polyester, polyurethane, aliphatic polyamide-based fibers
(including 6-nylon and 6,6-nylon), aromatic polyamide-based fibers,
and the like.
[0026] The ratio of the cellulose fibers, the animal fibers, and
the synthetic fibers in the fiber material (hydrophobic fiber) is
not particularly limited, and can be set to any desired ratio.
[0027] The hydrophobic fiber is constituted by affixing a silicone
elastomer film having methylhydrogen polysiloxane crosslinked with
zinc stearate as a crosslinking agent to at least a portion of the
surface of the natural fiber within the fiber material.
[0028] Due to the silicone elastomer film, the surface tension of
the hydrophobic fiber is adjusted to be less than 72 mN/m, and more
preferably, is adjusted to be less than or equal to 35 mN/m.
Consequently, it can be made difficult for water having a surface
tension of 72 mN/m, or sebaceous oil or cooking oil having a
surface tension of approximately 35 mN/m to permeate into the
hydrophobic fiber.
[0029] Moreover, the surface tension can be determined by way of a
so-called Dupont method. More specifically, initially, twelve types
of mixed reagents having different concentrations from each other
are prepared by mixing isopropyl alcohol (IPA) and distilled water.
These twelve types of mixed reagents are classified into twelve
grades from a 1st grade through a 12th grade according to the
mixing ratios shown in Table 1. In Table 1, there is also shown
together therewith surface tensions for each of the grades.
[0030] The surface tension of the measurement samples can be
determined by dropping the mixed reagents onto the measurement
samples in order from a small grade number to a large grade number,
for example. More specifically, dropping of the mixed reagents is
carried out five times, in a manner so that the diameter of the
mixed reagent on the measurement samples by one dropping thereof is
roughly 3 mm. After being left standing for 10 seconds, the grade
number of the mixed reagent in which two or three droplets are left
remaining in the form of droplets is determined. Thereamong, the
surface tension of mixed reagents for which the grade number
thereof is maximum can be recognized as being the surface tension
of the measurement sample.
[0031] Stated otherwise, when the surface tensions of a solid and a
liquid are compared, in the case that the surface tension of the
liquid is large, the liquid is easily repelled by a solid.
Accordingly, with the hydrophobic fiber according to the present
embodiment, in which the surface tension is adjusted to be less
than or equal to 35 mN/m, the mixed reagent is maintained in
droplet form when the first grade through the third grade mixed
reagents are dropped thereon.
TABLE-US-00001 TABLE 1 Volume % Distilled Surface Tension Grade IPA
Water (mN/m) 1 2 98 59.0 2 5 95 50.0 3 10 90 42.0 4 20 80 33.0 5 30
70 27.5 6 40 60 25.4 7 50 50 24.6 8 60 40 23.8 9 70 30 23.1 10 80
20 22.3 11 90 5 21.5 12 100 0 20.8
[0032] Further, the silicone elastomer film preferably contains
conductive fine particles made of an n-type semiconductor
containing zinc oxide as a principal component. More specifically,
the conductive fine particles are made from an n-type semiconductor
in which zinc oxide is doped with a trivalent metal. From the
standpoint of improving conductivity, as the trivalent metal, a
metal doped with at least one of aluminum and gallium can be
suitably used.
[0033] Further, from the standpoint of improving conductivity, it
is preferable that the average particle diameter of primary
particles of the conductive fine particles lies within a range of
roughly 100 to 200 nm, and the average particle diameter secondary
particles thereof lies within a range of roughly 4 to 5 .mu.m. The
average particle diameter can be measured with a commercially
available particle size analyzer or the like, and for example, can
be set to a particle diameter at an integrated value of 50% (D50)
in a particle size distribution obtained by a laser
diffraction/scattering method.
[0034] A process of obtaining the hydrophobic fiber which is
configured basically in the manner described above will be
described in relation to a manufacturing method according to the
present embodiment.
[0035] First, particles of a silicone elastomer containing
methylhydrogen polysiloxane as a principal component thereof are
dispersed in an aqueous dispersion medium such as water to thereby
prepare an aqueous dispersion liquid. A commercially available
product such as "Light Silicone P-316" (trade name) (manufactured
by Hokko Chemicals Co., Ltd.) or the like can be used as this type
of methylhydrogen polysiloxane. Further, the aqueous dispersion
liquid can also be obtained, for example, by mixing the
aforementioned methylhydrogen polysiloxane together with a silicone
emulsion at an appropriate concentration. A commercially available
product such as "X-51-1318" (trade name) (a silicon emulsion
manufactured by Shin-Etsu Chemical Co., Ltd.) can be used as this
type of silicone emulsion. Moreover, the aqueous dispersion may be
prepared solely from particles of a silicone elastomer containing
methylhydrogen polysiloxane as a principal component thereof, and
an aqueous dispersion medium such as water, without containing a
silicone emulsion.
[0036] Zinc stearate is mixed as a crosslinking agent in the
aqueous dispersion liquid to thereby obtain a mixed solution. A
commercially available product such as "F-12E" (trade name)
(manufactured by Hokko Chemicals Co., Ltd.) or the like can be used
as this type of zinc stearate. In the case of obtaining a silicone
elastomer film containing conductive fine particles, the conductive
fine particles are further dispersed in the mixed solution. A
commercially available product such as "Z-SDN" (a 25% dispersion of
conductive zinc oxide manufactured by Satoda Chemical Industrial
Co., Ltd.) or the like can be used as the conductive fine
particles.
[0037] An anionic softening agent, for example, may be further
added to the mixed solution as a modifying agent for adjusting the
surface tension of the finally obtained hydrophobic fiber. In other
words, the surface tension of the hydrophobic fiber can be
appropriately adjusted, for example, by adjusting the degree to
which the silicone elastomer particles undergo crosslinking due to
such a modifying agent. A commercially available product such as
"Hisofter ATS-2" (trade name) (manufactured by Meisei Chemical
Works, Ltd.) can be used as this type of modifying agent.
[0038] Further, in regards to the mixed solution, the
concentrations of each of the silicone elastomer particles, the
zinc stearate, the conductive fine particles, and the modifying
agent may be appropriately adjusted according to the material and
form, and the shape and dimensions of the fiber material, so that
the surface tension of the fiber material becomes less than 72
mN/m, and more preferably, less than or equal to 35 mN/m.
[0039] After the fiber material containing the natural fibers is
immersed in the thus prepared mixed solution, the liquid is wrung
out from the fiber material. Thereafter, the silicone elastomer
particles are crosslinked with zinc stearate as a crosslinking
agent, by carrying out a heating treatment or the like with respect
to the fiber material on which a drying treatment was performed.
The heating treatment can be carried out using existing heating
equipment such as a heat setter, for example.
[0040] Consequently, a silicone elastomer film is formed, and the
film can be firmly affixed to the surface of the natural fiber
primarily by an anchor effect. As a result, a hydrophobic fiber is
obtained having a surface tension of less than 72 mN/m.
[0041] In the hydrophobic fiber obtained through the above process,
by providing the silicone elastomer film, the hydrophobic fiber is
rendered hydrophobic without the use of a fluorine compound, and
therefore, it is possible to prevent a decrease in the intrinsic
moisture absorption/desorption property of the natural fiber.
Further, with the hydrophobic fiber, it is possible to suppress
swelling due to absorption of water during washing with water or
the like, which is known to be a defect of natural fibers, and
therefore, the rapid drying ability, durability, wash-and-wear
ability, etc., can be improved. Further, by being brought close to
the surface tension of sebaceous oil and cooking oil, which are
likely to be a cause of oil stains in everyday life, the
hydrophobic fiber exhibits an oil repellent property, and
therefore, it is unlikely for oil stains to become adhered thereto,
and the antifouling ability can also be enhanced.
[0042] Furthermore, since due to its elasticity, the silicone
elastomer film can freely expand and contract in following relation
with deformation of the fiber material, it is possible to maintain
the state in which the silicone elastomer film is firmly affixed to
the surface of the fiber material. Consequently, for example, even
in the event that frictional forces or the like are applied to the
hydrophobic fiber in water or in a chemical cleaning agent when
washing or dyeing is performed, it is possible to prevent the
silicone elastomer film from peeling off from the surface of the
fiber material.
[0043] Accordingly, the hydrophobic fiber is capable of improving a
rapid drying ability, durability, a wash-and-wear ability, and an
antifouling ability, etc., while also providing a moisture
adsorption/desorption property superior to that of the original
natural fiber, and in addition, is capable of maintaining the state
in which such physical properties are enhanced over a prolonged
period. Hence, compared to an untreated natural fiber, the amount
of water used during washing of the hydrophobic fiber with water
can be reduced, which is also preferable from the standpoint of the
environment.
[0044] Further, the silicone elastomer film is affixed to the fiber
material mainly by a mechanical action such as an anchor effect or
the like. Stated otherwise, the majority of the functional groups
in the natural fiber exist in a state in which chemical bonds such
as covalent bonding are not formed with the silicone elastomer
film. Therefore, when the hydrophobic fiber is dyed, the functional
groups in the natural fiber and the dye are capable of reacting
sufficiently with each other, and dying with the dye can be
performed suitably while avoiding color unevenness. Stated
otherwise, the hydrophobic fiber is excellent in terms of its
ability to be dyed, and piece dyeing thereof can be performed
easily.
[0045] As a result, it is possible to stock the hydrophobic fiber
in an undyed and unsewn condition, to carry out dying on the basis
of information of fashionable colors collected immediately prior to
sale thereof, and to directly perform sewing or the like thereon to
quickly result in a textile product. More specifically, it is
possible to provide commercial products in which rapidly changing
fashionable colors and patterns are accurately captured in a short
delivery period, and to reduce defective inventory and make
effective use of resources, and hence, to reduce the cost of sewn
products in which the hydrophobic fiber is used.
[0046] Further, when the conductive fine particles are dispersed in
the silicone elastomer film, the conductive fine particles can be
firmly supported on the surface of the hydrophobic fiber.
Therefore, falling off or separation of the conductive fine
particles from the hydrophobic fiber due to washing, dyeing or the
like can be effectively suppressed. Consequently, the functions
indicated below can be further added to the hydrophobic fiber, and
the effectiveness of such functions is not easily lowered even
after washing of the hydrophobic fiber, and the functions exhibit
suitable sustainability.
[0047] More specifically, the conductive fine particles absorb
ultraviolet rays and both absorb and reflect infrared rays. On the
other hand, the conductive fine particles transmit visible light.
Accordingly, it is possible for an ultraviolet shielding function
and an infrared shielding function to be added, without inhibiting
the development of color in the hydrophobic fiber by the conductive
fine particles. In addition, since conductivity can be suitably
added to the hydrophobic fiber, electrostatic charging is
prevented, and generation of static electricity can effectively be
avoided. Furthermore, excellent deodorizing and antibacterial
properties can be added.
[0048] Further, generally, a wearer of clothing tends to experience
a feeling of irritation from the clothing due to static electricity
generated on the surface or the like of the clothing acting on the
open pores, or by coming into contact with a fiber that possesses
low flexibility. On the other hand, the conductive fine particles
which mainly contain zinc oxide possess an astringent action.
Accordingly, it is possible to suppress opening of the pores of a
wearer of clothing or the like made from a hydrophobic fiber
containing the conductive fine particles. Furthermore, in such a
hydrophobic fiber, as described above, in addition to preventing
the generation of static electricity due to the conductive fine
particles, the hydrophobic fiber exhibits excellent flexibility due
to the presence of the silicone elastomer film. Owing to this
feature, it is possible to reduce irritation to the wearer.
[0049] Although a preferred embodiment of the present invention has
been described above, the present invention is not limited to the
present embodiment, and various changes and modifications may be
adopted therein without departing from the scope of the
invention.
[0050] For example, a hydrophobic fiber in which a silicone
elastomer film that does not contain conductive fine particles is
affixed to the surface thereof may be obtained from an aqueous
dispersion in which the conductive fine particles are not mixed
therein.
EXAMPLES
[0051] Hereinafter, the present invention will be described in
detail with reference to various examples thereof. However, the
present invention is not limited to such examples.
[0052] Descriptions will be given of inventive examples of
hydrophobic fibers, which are obtained by forming on the following
fiber materials a silicone elastomer film containing conductive
fine particles, or a silicone elastomer film that does not contain
conductive fine particles. More specifically, a fiber material made
from a material A of 100% cotton was used in the states of knitted
fabrics A1 and A2, and a woven fabric A3. The knitted fabric A1 was
a moss stitch knitted fabric prepared using No. 40 single yarn at
26-gauge, 26 inches. The knitted fabric A2 was a plain stitch
knitted fabric prepared using No. 30 single yarn at 38-gauge, 67
inches. The woven fabric A3 was a plain weave (broad) fabric with
120 warp yarns per inch and 60 weft yarns per inch.
[0053] As the form of the fiber material, a woven fabric B1 is a
plain weave (Ox) with 116 warp yarns per inch of 100% cotton yarns
prepared using No. 40 single yarn, and 68 weft yarns per inch in
which cotton and linen are blended at a 50:50 ratio. Stated
otherwise, in the woven fabric B1, cotton and linen are blended at
an 82:18 ratio.
[0054] The form of a fiber material composed of a material C in
which cotton and Tencel are mixed at an 80:20 ratio was a 2/2 left
twill woven fabric C1 with 126 warp yarns per inch, and 77 weft
yarns per inch, prepared using No. 30 single yarn.
[0055] The form of a fiber material composed of a material D in
which cotton and Tencel are blended at an 88:12 ratio was a moss
stitch knitted fabric D1 prepared using 26 signal yarns at
26-gauge, 20 inches.
[0056] The form of a fiber material composed of a material E of
100% Viscose Rayon was a plain weave woven fabric E1 with 112 warp
yarns per inch, and 94 weft yarns per inch, prepared using No. 40
single yarn.
[0057] Among the fiber materials, initially, desizing, scouring,
and bleaching, dehydration, and drying were carried out on each of
the knitted fabrics A1, A2, and D1. Further, initially, desizing,
scouring, and bleaching were carried out on each of the woven
fabrics A3, B1, C1, and E1. Next, in order to carry out a modifying
treatment on the fiber material, initially, a mixed solution was
prepared. In this instance, in the modifying treatment with respect
to the test specimens A1, A2, B1, C1, and D1, a silicone elastomer
film containing conductive fine particles was formed, and in the
modifying treatment with respect to the test specimens A3 and E1, a
silicone elastomer film containing no conductive fine particles
therein was formed.
[0058] Therefore, in order to carry out the modifying treatment
with respect to the test specimens A1, A2, B1, C1, and D1, a mixed
solution was prepared so as to contain 20 g/L of "light silicone
P-316" (methylhydrogen polysiloxane), 30 g/L of "X-51-1318"
(silicone emulsion), 20 g/L of "F-12 E" (zinc stearate), and 80 g/L
of "Z-SDN" (a 25% dispersion of conductive zinc oxide).
[0059] Further, in the modifying treatment with respect to the test
specimen A3, a mixed solution was prepared so as to contain 20 g/L
of "light silicone P-316" (methylhydrogen polysiloxane), and 20 g/L
of "F-12E" (zinc stearate). In the modifying treatment with respect
to the test specimen E1, a mixed solution was prepared so as to
contain 50 g/L of "light silicone P-316" (methylhydrogen
polysiloxane), and 50 g/L of "F-12E" (zinc stearate).
[0060] After each of the above-described fiber materials were
immersed respectively in each of the mixed solutions, the solutions
were wrung out from the fiber materials. As a result, a weight
ratio (pickup) of the weight of the attached mixed solution to the
weight of the fiber material before immersion was set to 70%. The
fiber materials were subjected to a drying treatment at 150.degree.
C. for one minute and thirty seconds using a heat setter
manufactured by IL SUNG MACHINERY, Co., Ltd.
[0061] Next, among the fiber materials after implementation of the
drying treatment thereon, the knitted fabrics A1, A2, and D1 were
subjected to a heat treatment at 170.degree. C. for two minutes
using the aforementioned heat setter in order to obtain hydrophobic
fibers.
[0062] Further, concerning the other fiber materials (woven fabrics
A3, B1, C1, and E1), they were subjected to a heat treatment at
170.degree. C. for two minutes using a baking machine manufactured
by SANDO ENGINEERING Co., Ltd., and thereafter, were subjected to a
shrink-proofing process in order to obtain hydrophobic fibers.
[0063] The hydrophobic fibers which were obtained in the foregoing
manner were used as inventive examples. On the other hand, fiber
materials which were not modified in the above-described manner,
and more specifically, which were not provided with the
above-described silicone elastomer film, were used as comparative
examples.
(Surface Tension)
[0064] Concerning each of the test specimens A1 to A3, B1, C1, and
D1, excluding test specimen E1, from among the fiber materials of
the inventive examples and the comparative examples, the surface
tension before washing with water (zero times), the surface tension
after washing was performed one time, the surface tension after
washing was performed 25 times and the surface tension after
washing was performed 50 times were measured. Further, concerning
the test specimen E1, the surface tension before washing with water
(zero times), and the surface tension after washing was performed
20 times were measured respectively.
[0065] Washing was carried out using a home electric washing
machine VH-30S manufactured by Toshiba Corporation. More
specifically, water and each of the measurement samples were
inserted into a washing tub in a manner so that the measurement
samples became 1 kg with respect to 30 L of water, or stated
otherwise, so that the bath ratio was 1:30. At this time, the water
temperature was set to 30.degree. C. to 40.degree. C. Further, the
washing condition was set to a strong water flow condition, and
washing was carried out one time for 15 minutes. Further, the
surface tension was measured using the Dupont method described
above. The results thereof are shown in Table 2.
TABLE-US-00002 TABLE 2 Surface Tension (mN/m) Inventive Example
Comparative Example A1 Washing 0 33 .gtoreq.72 (times) 1 33
.gtoreq.72 25 42 .gtoreq.72 100 59 .gtoreq.72 A2 Washing 0 33
.gtoreq.72 (times) 1 42 .gtoreq.72 25 42 .gtoreq.72 100 50
.gtoreq.72 A3 Washing 0 33 .gtoreq.72 (times) 1 33 .gtoreq.72 25 42
.gtoreq.72 100 50 .gtoreq.72 B1 Washing 0 42 .gtoreq.72 (times) 1
42 .gtoreq.72 25 50 .gtoreq.72 100 59 .gtoreq.72 C1 Washing 0 33
.gtoreq.72 (times) 1 33 .gtoreq.72 25 42 .gtoreq.72 100 42
.gtoreq.72 D1 Washing 0 42 .gtoreq.72 (times) 1 42 .gtoreq.72 25 42
.gtoreq.72 100 50 .gtoreq.72 E1 Washing 0 50 .gtoreq.72 (times) 10
50 .gtoreq.72 20 50 .gtoreq.72
[0066] As shown in Table 2, the surface tension of the fiber
materials according to the inventive examples was less than 72 mN/m
both before washing and after washing. In contrast thereto,
concerning the intrinsic surface tension of the fiber materials of
the comparative examples, that is, the intrinsic surface tension of
the fiber materials before being subjected to the modifying
treatment, the surface tension thereof was greater than or equal to
of 72 mN/m both before washing and after washing.
[0067] Accordingly, with the hydrophobic fiber, by providing the
silicone elastomer film on the surface of the fiber material, the
surface tension of the fiber material can be made less than the
surface tension of water, and the hydrophobic fiber can suitably be
made hydrophobic. Further, even in the event that frictional forces
or the like are applied to the hydrophobic fiber in water at a time
of washing, it is possible to prevent the silicone elastomer film
from peeling off from the surface of the natural fibers.
Consequently, even after repeated washing, it is possible for the
aforementioned surface tension of the hydrophobic fiber to be
maintained.
(Oil Repellent Property)
[0068] An oil repellency test was conducted on fiber materials
according to the inventive examples in conformity with the AATCC
118-2002 method. In such a method, eight types of hydrocarbon
solvents having different surface tensions are defined as test
liquids, to which grade numbers are assigned in a manner so that
the hydrocarbon solvents having larger surface tensions are
assigned smaller grade numbers. For example, the test liquids are
left standing for thirty seconds respectively at five locations, in
order from those having smaller grade numbers, on the surface of
the above-described fiber materials, from positions of about 0.6 cm
in a height dimension, and so as to have sizes of about 5 mm in
diameter. At this time, the oil repellent property of the surface
of the fiber materials can be determined from the grade number of
the test liquid, in which two or three droplets are left remaining
in the form of droplets at the above-mentioned location.
[0069] The oil repellent properties, which were determined in the
manner described above, of any of the fiber materials according to
the inventive examples were of a grade number capable of
sufficiently suppressing the permeation of cooking oils such as
olive oil (surface tension 35.8 mN/m) and cottonseed oil (surface
tension 35.4 mN/m) or the like. Therefore, since the hydrophobic
fiber is brought close to the surface tension of sebaceous oil and
cooking oil, which are likely to be a cause of oil stains in
everyday life, and exhibits an oil repellent property, it is
unlikely for oil stains to become adhered thereto, and the
antifouling ability can also be improved.
(Rapid Drying Ability)
[0070] Concerning each of the test specimens A1 to A3, B1, C1, and
D1, excluding test specimen E1, from among the fiber materials
according to the inventive examples and the comparative examples, a
rapid drying ability test as described below was performed in order
to evaluate the rapid drying ability thereof.
[0071] First, the weight (dry weight of the fiber material after
drying) of the test specimens A1 to A3, B1, C1, and D1 according to
the inventive examples and the comparative examples after drying at
105.degree. C. for two hours was measured. Next, the test specimens
were washed in the same manner as in the above-described washing
method, except that the washing time was set to 30 minutes, and the
weight after dehydration was performed for 5 minutes (weight of
fiber material after dehydration) was measured. Next, the test
specimens were suspended and dried in a room at a temperature of
25.degree. C..+-.1.degree. C. and a humidity of 55%.+-.5% (RH). At
this time, the weight of the test specimens (weight of the fiber
materials during suspension drying) was measured with each elapse
of five minutes.
[0072] A difference between the weight of the fiber materials after
drying and the weight of the fiber materials after dehydration is
the weight (moisture weight after dehydration) of the moisture
contained in the test specimens after dehydration. Therefore, the
moisture content (%) of the test specimens when the suspension
drying time is zero minutes is given by the formula, water content
weight after dehydration (g)/weight of fiber material after drying
(g). Further, the moisture content (%) of the test specimens each
time that suspension drying is performed is given by the formula
(weight of fiber material during suspension drying (g)-weight of
fiber material after drying (g))/weight of fiber material after
drying (g). Moisture content ratios of the test specimens of the
inventive examples and the comparative examples which were
calculated in this manner are shown in Table 3, together with the
suspension drying time period.
TABLE-US-00003 TABLE 3 Suspension Drying Water Content Ratio (%)
Time Period (minutes) Inventive Example Comparative Example A1 0
49.3 78.0 20 36.7 64.6 60 14.6 36.7 70 10.4 29.3 100 3.3 9.9 110
2.9 7.1 A2 0 38.7 81.9 5 35.4 77.8 30 17.9 57.3 50 8.5 42.3 70 6.0
28.0 100 2.5 10.2 110 3.5 6.8 A3 0 30.5 63.2 5 27.4 57.4 30 6.6
31.6 50 1.6 11.5 70 0.3 1.1 B1 0 44.8 68.5 5 37.7 61.6 10 31.5 55.1
20 21.6 42.6 30 11.9 30.3 40 4.1 17.9 50 0.9 7.1 C1 0 35.3 67.5 5
30.3 62.4 30 26.3 58.1 50 19.2 50.3 70 3.9 26.6 100 1.9 18.7 110
0.9 12.2 120 9.5 D1 0 44.0 60.5 5 41.8 58.1 30 28.6 45.8 50 18.6
35.0 70 10.9 25.9 100 2.9 13.2 110 1.7 9.8
[0073] As can be understood from Table 3, first, at a point in time
when the suspension drying time period was zero minutes, that is,
in a state in which only dehydration was performed, the water
content ratio of the fiber materials according to the inventive
examples was lower than the water content ratio of the fiber
materials according to the comparative examples. Therefore, it can
be understood that, with the hydrophobic fiber, at a time of
washing in water, swelling by absorption of water is
suppressed.
[0074] From the rapid drying ability test described above, there is
further shown in Table 4 the suspension drying time periods (in
minutes) required for the water content of the fiber materials
according to the inventive examples and the comparative examples to
decrease to 10%. Further, in Table 4, results are also shown
together therewith by which a shortening ratio (Y/X).times.100(%)
was determined, in which the suspension drying time periods Y of
the fiber materials according to the inventive examples were
shortened with respect to the suspension drying time periods X of
the fiber materials according to the comparative examples.
TABLE-US-00004 TABLE 4 Suspension Drying Time Period Required for
Water Content Ratio Shortening Ratio to Decrease to 10% (minutes)
of Drying Time Inventive Example Comparative Example Period (%) A1
70.0 100.0 30 A2 47.0 100.0 50 A3 25.0 52.0 50 B1 32.0 47.0 30 C1
62.0 117.0 50 D1 73.0 109.0 30
[0075] From Table 4, it can be understood that, with the fiber
materials according to the inventive examples, the time periods
required for drying are reduced by about 30% to 50% as compared
with those of the fiber materials according to the comparative
examples. Accordingly, with the hydrophobic fiber, it is possible
to effectively improve the rapid drying ability in comparison with
an untreated fiber material.
(Moisture Absorption/Desorption Property)
[0076] Concerning each of the test specimens A1 to A3, C1, and D1,
excluding test specimens B1 and E1, from among the fiber materials
according to the inventive examples and the comparative examples,
the moisture absorption/desorption property (moisture content
ratio) thereof was evaluated in conformity with the Boken method by
the general incorporated association of the Boken Quality
Evaluation Institute. More specifically, first, a test specimen of
the aforementioned fiber material having a size of 20 cm.sup.2 was
exposed to an environment of 40.degree. C. and 90% (RH) for 4
hours, whereby moisture was absorbed into the test specimen.
Thereafter, moisture was released from the test specimen by
exposing the test specimen for 4 hours under an environment of
20.degree. C..times.65% (RH). At this time, the weight (g) of the
test specimen was measured with each elapse of one hour, and the
moisture absorption/desorption property (moisture content ratio)
(%) was obtained from such a change in weight. The results thereof
are shown in Table 5. The environment of 40.degree. C..times.90%
(RH) is a high temperature high humidity state which approximates
the temperature and humidity in clothing when a person has
performed light exercise. The environment of 20.degree.
C..times.65% (RH) is a standard state approximating that of outside
air temperature.
TABLE-US-00005 TABLE 5 Moisture Absorption/Desorption Property
(Water Content Ratio) (%) Inventive Example Condition (RH)
40.degree. C. .times. 90% 20.degree. C. .times. 65% Time (h) 1 2 3
4 5 6 7 8 A1 7.9 9.6 10.4 11.0 7.5 7.0 6.9 6.9 A2 9.1 10.5 11.1
11.5 7.5 7.0 7.0 6.9 A3 8.3 9.8 10.5 11.0 7.3 6.7 6.6 6.6 C1 9.6
11.3 12.1 12.5 8.2 7.8 7.7 7.6 D1 7.2 9.3 10.3 11.1 8.5 8.0 7.7 7.5
Comparative Example Condition (RH) 40.degree. .times. 90%
20.degree. C. .times. 65% Time (h) 1 2 3 4 5 6 7 8 A1 8.0 9.5 10.3
10.8 7.4 7.1 7.0 7.0 A2 9.9 10.6 10.9 11.2 7.7 7.3 7.2 7.1 A3 8.9
10.2 10.8 11.1 7.1 6.9 6.9 6.8 C1 10.1 11.5 12.0 12.2 8.3 7.9 7.8
7.8 D1 7.9 10.1 11.0 11.5 8.7 8.1 7.9 7.8
[0077] From Table 5, it can be understood that the moisture
absorption/desorption property of the fiber materials according to
the inventive examples is approximately the same as that of the
fiber materials of the comparative examples. More specifically,
with the hydrophobic fibers, the intrinsic moisture
absorption/desorption property of the fiber materials can be
adequately maintained.
(Ultraviolet Cut Rate)
[0078] Among the fiber materials according to the inventive
examples and the comparative examples, concerning the test
specimens A1, A2, B1, and D1 on which the silicone elastomer film
containing conductive fine particles was formed, an ultraviolet cut
rate of the respective test specimens was evaluated using an
ultraviolet-visible-near infrared spectrophotometer "UV-3150"
(trade name) manufactured by Shimadzu Corporation. More
specifically, in regard to the test specimens of the
above-described fiber materials, the transmittance thereof at
wavelengths of 220 nm to 400 nm was measured, and a value obtained
by subtracting the obtained measurement value from 100 was defined
as the ultraviolet cut rate (%). The results thereof are shown in
Table 6.
TABLE-US-00006 TABLE 6 Ultraviolet Cut Rate (%) Inventive Example
Comparative Example A1 88.2 82.9 A2 82.9 74.4 B1 80.6 72.1 D1 93.3
82.0
[0079] From Table 6, it can be understood that, with the fiber
materials according to the inventive examples, higher ultraviolet
cut rates are exhibited in comparison with those of the comparative
examples. Specifically, with the hydrophobic fiber, ultraviolet
rays can be effectively absorbed by the conductive fine particles
contained within the silicone elastomer film.
(Infrared Absorption Ability)
[0080] In regards to each of the test specimens A1, A2, B1, C1, and
D1 on which the silicone elastomer film containing conductive fine
particles was formed, infrared absorption abilities of the
inventive examples and the comparative examples were compared by
the following method. Specifically, initially, each of the test
specimens was placed in an opening of a box having an internal
capacity of 60 ml, and having cork for heat insulation provided on
a side wall thereof. Further, a thermocouple temperature sensor was
disposed inside the box in which the test specimens were placed so
that the distance from the test specimens was 2 mm. Next, from
among both surfaces of the test specimens, a 100 W infrared light
of a near-infrared ray lamp was irradiated from one surface of the
test specimens on an opposite side from the thermocouple
temperature sensor. As the near-infrared ray lamp, model number
IR100/110V100WR manufactured by Toshiba Corporation was used, and
the distance from the test specimens was 150 mm. Also, the
temperature of the test room was set to 25.degree. C..+-.2.degree.
C. and the humidity was set at 40%.+-.5% RH.
[0081] In accordance with this setup, the temperature inside the
box that was irradiated with infrared light through the test
specimens was made to rise, and thus at this time, the change in
temperature was measured over time with the thermocouple
temperature sensor. Within the measurement results, the difference
between the inventive examples and the comparative examples was
taken in regard to each of the temperatures thereof after 15
minutes, 4 hours, and 8 hours from the initial irradiation by the
near infrared ray lamp, and the infrared absorption ability of each
was compared. The results thereof are shown in Table 7.
TABLE-US-00007 TABLE 7 Temperature (.degree. C.) Irradiation
Inventive Comparative Time Example Example Difference Al 15 minutes
42.5 44.4 -1.9 4 hours 44.2 46.2 -2.0 8 hours 44.2 46.1 -1.9 A2 15
minutes 43.2 45.5 -2.3 4 hours 43.8 46.1 -2.3 8 hours 44.0 46.2
-2.2 B1 15 minutes 42.1 44.6 -2.5 4 hours 43.5 45.9 -2.4 8 hours
42.7 45.3 -2.6 C1 15 minutes 43.5 45.3 -1.8 4 hours 43.6 45.5 -1.9
8 hours 44.8 46.5 -1.7 D1 15 minutes 43.8 46.0 -2.2 4 hours 45.1
47.4 -2.3 8 hours 45.5 47.7 -2.3
[0082] From Table 7, it can be understood that the rise in
temperature due to infrared radiation was less with the fiber
materials of the inventive examples than with the fiber materials
of the comparative examples. Stated otherwise, with the hydrophobic
fiber, it is possible to effectively absorb and reflect infrared
rays. Further, from the fact that the effect of suppressing a rise
in temperature due to infrared irradiation of the hydrophobic fiber
is maintained even after the elapse of 8 hours from the initial
irradiation with infrared rays, it can be understood that such an
effect possesses excellent sustainability.
(Wash-and-Wear Ability)
[0083] A wash-and-wear ability evaluation test was performed on the
fiber materials A1 according to the inventive example and the
comparative example, and on the fiber material E1 according to the
inventive example. This test was conducted at the general
incorporated association of the Boken Quality Evaluation
Institute.
[0084] In greater detail, first, three test specimens of 400
mm.sup.2 were prepared from the aforementioned fiber materials.
With respect thereto, washing and drying were carried out in
conformity with the JIS L 1096 G method (JIS L 0217 103). More
specifically, water and the measurement samples were inserted into
a washing tub so that the bath ratio was 1:40. At this time, the
water temperature was set to 40.degree. C., and during washing, the
detergent "Attack" (trade name) (a synthetic detergent manufactured
by Kao Corporation) was added at an amount of 1 g/L. Further, the
following washing conditions were employed: washing with a strong
water flow for twelve minutes, drainage, centrifugal dehydration
for two minutes, rinsing for two minutes, drainage, centrifugal
dehydration for two minutes, rinsing for two minutes, drainage, and
centrifugal dehydration for four minutes were carried out in this
order to thereby complete one washing cycle. Then, after completion
of washing, the wash-and-wear ability was evaluated after carrying
out suspension drying in a manner so that the longitudinal
direction of the test specimens was oriented along the vertical
direction.
[0085] In regards to the fiber materials A1 according to the
inventive examples and the comparative examples, the wash-and-wear
abilities thereof were evaluated after washing was performed one
time and after washing was performed five times, respectively.
Further, in regards to the fiber material E1 according to the
inventive example, the wash-and-wear ability thereof was evaluated
after washing was performed one time and after washing was
performed twenty times, respectively. The results thereof are shown
in Table 8.
[0086] The wash-and-wear ability is an index representing the
degree of wrinkles that remain after washing, and is evaluated by
making a comparison with an evaluation replica prescribed by the
AATCC TEST METHOD 124, and assigning a grade (1st grade through 5th
grade) thereto. The higher the grade, the fewer amount of wrinkles
that remain.
TABLE-US-00008 TABLE 8 Wash-and-Wear Ability (grade) Inventive
Example Comparative Example A1 Washing 1 3.5 2.7 (times) 5 3.2 2.3
E1 Washing 5 3.5 (times) 20 3.3
[0087] From the results shown in Table 8, it can be understood that
the fiber materials of the inventive examples had more superior
grades in relation to the wash-and-wear ability in comparison with
those of the fiber material of the comparative example, and even
after repeated washing, it was possible to maintain the
wash-and-wear ability at a grade of 3.2 or higher. Stated
otherwise, with the hydrophobic fiber, it is possible to improve
the wash-and-wear ability, and to enable the wrinkle cutting ratio
(the degree to which wrinkles are removed) after washing to be
greater than or equal to 50% in comparison with an untreated fiber
material, and therefore, as a shape stabilizing process, a
sufficient wash-and-wear ability can be demonstrated over a
prolonged period.
(Bursting Strength)
[0088] The bursting strengths of each of the woven fabrics A3, B1,
and D1 according to the inventive examples and the comparative
examples were measured in conformity with the JIS L 1096 A method
(Mullen type method). More specifically, initially, five test
specimens each having a size of 15 cm.times.15 cm were collected.
In addition, using a Mullen type bursting tester, with the surface
of the test specimens facing upward, the test specimens were
gripped by a clamp with uniform tension applied thereto. Pressure
was applied to the test specimens from a rear side through a rubber
film, and the strength A (kPa) at which the rubber film broke
through the test specimens, and the strength B (kPa) of only the
rubber film at a time of breakage thereof were measured. Then, the
bursting strength Bs (kPa) was determined in accordance with the
following equation (2), and the average value thereof was
calculated as the bursting strength.
Bs=A-B (2)
[0089] The bursting strength was calculated by carrying out the
above-described measurement, for each of a condition in which the
test specimens were left standing for 24 hours at 20.degree. C. and
65% relative humidity, and a condition in which the test specimens
were immersed in water and moistened so that the moisture content
thereof became 100%. The results thereof are shown in Table 9.
TABLE-US-00009 TABLE 9 Bursting Strength (kPa) Inventive Example
Comparative Example Dry Moist Dry Moist A1 318.5 303.8 298.9 303.8
A2 480.0 539.0 495.0 382.0 D1 564.0 686.0 461.0 588.0
[0090] From Table 9, it can be understood that, both in a dry
condition and a moist condition, the fiber materials of the
inventive examples exhibit a bursting strength which is
substantially equivalent to or greater than that of the fiber
materials of the comparative examples. Therefore, the hydrophobic
fiber is also excellent in terms of its bursting strength.
(Tearing Strength)
[0091] The tearing strengths of each of the woven fabrics A3, B1,
C1, and E1 according to the inventive examples and the comparative
examples were measured in conformity with the JIS L 1096 D method
(pendulum method). More specifically, initially, five test
specimens each having a size of 63 mm.times.roughly 100 mm were
collected. In addition, using an Elemendorf tearing strength
tester, short sides of both ends in the longitudinal direction of
the test specimens were gripped. Then, after having introduced a
cut of 20 mm approximately in the center of the elongate side of
the test specimens at a right angle to the elongate side, a load
was applied so as to pull in opposite directions on both ends of
the test specimens. In accordance with this method, the load (N) at
the time that a remaining 43 mm of the wefts were torn was taken to
represent the tearing strength in the longitudinal direction. By
setting the elongate side of the test specimens in the longitudinal
direction, it is also possible to measure the tearing strength in
the transverse direction in the same manner as the tearing strength
in the longitudinal direction.
[0092] The tearing strength was measured for each of a condition in
which the test specimens were left standing for 24 hours at
20.degree. C. and 65% relative humidity, and a condition in which
the test specimens were immersed in water and moistened so that the
moisture content thereof became 100%. The results thereof are shown
in Table 10.
TABLE-US-00010 TABLE 10 Tearing Strength (N) Inventive Example
Comparative Example Dry Moist Dry Moist A1 longitudinal 12.0 12.0
11.0 14.0 transverse 8.0 19.0 6.0 7.5 B1 longitudinal 59.0 50.0
40.0 60.0 transverse 38.0 51.0 16.0 37.0 C1 longitudinal 52.0 40.0
29.5 21.0 transverse 30.5 26.0 22.5 18.0 E1 longitudinal 16.2 15.2
11.2 8.0 transverse 14.0 12.8 8.4 6.0
[0093] From Table 10, it can be understood that the tearing
strengths of the fiber materials of the inventive examples are
greater than those of the fiber materials of the comparative
examples, both in the longitudinal direction and in the transverse
direction. Further, in the fiber materials of the comparative
examples, the tearing strength at a time of being moist is reduced
by roughly 30% compared to the tearing strength thereof at a time
of being dry. In contrast thereto, with the fiber materials of the
inventive examples, the rate of the decrease in the tearing
strength at a time of being moist is on the order of roughly 10%
compared to the tearing strength thereof at a time of being dry.
More specifically, with the hydrophobic fiber, it is possible to
improve the tearing strength in comparison with an untreated fiber
material, and it is possible to maintain a high tearing strength
even when moist.
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