U.S. patent application number 11/663730 was filed with the patent office on 2008-06-05 for woven or knitted fabric and clothes containing crimped composite filaments and having an air permeability which increases when the fabric is wetted with water.
This patent application is currently assigned to TEIJIN FIBERS LIMITED. Invention is credited to Shigeru Morioka, Takeshi Yamaguchi, Satoshi Yasui, Masato Yoshimoto.
Application Number | 20080132133 11/663730 |
Document ID | / |
Family ID | 36119101 |
Filed Date | 2008-06-05 |
United States Patent
Application |
20080132133 |
Kind Code |
A1 |
Yasui; Satoshi ; et
al. |
June 5, 2008 |
Woven or Knitted Fabric and Clothes Containing Crimped Composite
Filaments and Having an Air Permeability Which Increases When the
Fabric is Wetted With Water
Abstract
A woven or knit fabric containing crimped composite fibers
having its air permeability enhanced by water wetting and being
useful in clothes such as outerwear, which woven or knit fabric
contains 10 to 100 mass % of composite fibers of side-by-side type
or eccentric core sheath type composed of polyester resin component
and polyamide resin component whose thermal shrinkages are
different from each other, the composite fibers having crimps
developed by heat treatment. The composite fibers exhibit humid
crimp factor HC.sub.F (%), as measured through a procedure
comprising immersing the same in water of 30.degree. C. for 2 hr,
pulling them up, interposing them between a pair of filter papers
at 30.degree. C. in a humidity of 90% RH within 60 sec of the
pulling up and applying a pressure of 0.69 mN/cm.sup.2 for 5 sec,
of .gtoreq.10% lower than the dry crimp factor DC.sub.F (%) after
dying by allowing them to stand still at 20.degree. C. in a
humidity of 65% RH for 24 hr, so that the woven or knit fabric
exerts of the effect of air permeability enhancement by water
wetting.
Inventors: |
Yasui; Satoshi; (Osaka,
JP) ; Yamaguchi; Takeshi; (Osaka, JP) ;
Yoshimoto; Masato; (Ehime, JP) ; Morioka;
Shigeru; (Ehime, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
TEIJIN FIBERS LIMITED
OSAKA JAPAN
JP
|
Family ID: |
36119101 |
Appl. No.: |
11/663730 |
Filed: |
September 27, 2005 |
PCT Filed: |
September 27, 2005 |
PCT NO: |
PCT/JP05/18238 |
371 Date: |
March 26, 2007 |
Current U.S.
Class: |
442/200 |
Current CPC
Class: |
D03D 15/47 20210101;
D10B 2501/00 20130101; A41B 2400/20 20130101; D03D 15/567 20210101;
D03D 15/00 20130101; D03D 15/44 20210101; D10B 2501/04 20130101;
A41B 17/00 20130101; D04B 1/16 20130101; A41D 31/00 20130101; D10B
2331/02 20130101; D04B 21/16 20130101; D10B 2401/02 20130101; A41D
31/14 20190201; D10B 2331/04 20130101; Y10T 442/3154 20150401 |
Class at
Publication: |
442/200 |
International
Class: |
D03D 15/00 20060101
D03D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 29, 1994 |
JP |
2004-283758 |
Sep 28, 2004 |
JP |
2004-281494 |
Jan 27, 2005 |
JP |
2005-019486 |
Claims
1. A woven or knitted fabric comprising a yarn comprising composite
filaments formed from a polyester resin component and a polyamide
resin component different from each other in thermal shrinkage and
bonded together in a side-by-side structure or in an eccentric
core-sheath structure, and having crimps manifested by heat
treatment applied thereto, the crimped composite filaments being
contained in a content of 10 to 100% by mass in the woven or
knitted fabric, and satisfying the following formula
(DC.sub.F-HC.sub.F).gtoreq.10% wherein DC.sub.F represents a
percentage of crimp of a sample of crimped composite filaments
taken from the woven or knitted fabric, determined by leaving the
sample to stand for 24 hours in a test environment at a temperature
of 20.degree. C. at a humidity of 65% RH to dry and HC.sub.F
represents a percentage of crimp of another sample of the taken
crimped composite filaments, determined by immersing the another
sample in water at a temperature of 30.degree. C. for 2 hours,
pulling up the sample from the water, holding the sample between a
pair of filter paper sheets in the ambient atmospheric air at a
temperature of 30.degree. C. at a humidity of 90% RH within 60 sec
after pulling up the sample, leaving the sample under a pressure of
0.69 mN/cm.sup.2 for 5 seconds to lightly wipe out water from the
sample, whereby the woven or knitted fabric exhibit an air
permeability which increases when the fabric is wetted with
water.
2. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases upon with water, wherein the polyester resin component
comprises a modified polyester resin in which
5-sodiosulfoisophthalic acid is copolymerized in an amount of 2.0
to 4.5 molar % based on the content of the acid component.
3. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the yarn
comprising the crimped composite filaments has a number of twists
of 0 to 300 turns/m.
4. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric contains the crimped composite filaments and
other filaments different from the crimped composite filaments.
5. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the other
filaments are selected from non-crimped filaments or filaments
showing a difference in percentage of crimp DC.sub.F-HC.sub.F of
10% or less.
6. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein when the
woven or knitted fabric comprising the crimped composite filaments
is subjected to determination of the stretchability of a
stretchable woven fabric in accordance with JIS L1096, 8.14.1
Method B, except that the load value applied to a sample woven or
knitted fabric test piece is altered to 1.47 N, where the woven or
knitted fabric is a woven fabric, a stretchability of the woven
fabric in at least one direction selected from the warp direction
and the weft direction is 10% or more, and where the woven or
knitted fabric is a knitted one, the stretchability of the knitted
fabric in at least one direction selected from the course direction
and the wale direction is 10% or more.
7. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric comprising the crimped composite filaments has a
multiply structure, and at least one ply thereof comprises the
crimped composite filaments in an amount of 30 to 100 mass % based
on the weight of the ply.
8. The woven or knitted fabric according to claim 4 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric is a knitted fabric having a tubular knitted
stitch, and the loop of the tubular knitted stitch is formed from a
yarn comprising the crimped composite filaments and the other
filaments.
9. The woven or knitted fabric according to claim 4 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric is a woven fabric, the yarn containing composite
filaments is a doubled yarn of the crimped composite filaments and
the other or the warp filaments, and the warp and weft yarns or the
warp or weft yarn of the woven fabric is constituted from a doubled
yarn of the crimped composite filaments and the other
filaments.
10. The woven or knitted fabric according to claim 4 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the yarns
composed of the crimped composite filaments and the yarn composed
of the other filaments are alternately arranged with one each other
in at least one direction selected from the warp direction and the
weft direction, or in at least one direction selected from the
course direction and the wale direction.
11. The woven or knitted fabric according to claim 4 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein from the
crimped composite filaments and the other filaments, a core-sheath
composite yarn is formed, the core portion of the composite yarn is
formed from the crimped composite filaments, and the sheath portion
is formed from the other filaments.
12. The woven or knitted fabric according to claim 4 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the other
filaments are selected from polyester filaments.
13. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric is one treated with a water-absorbing agent.
14. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric is one treated with a water-repellent
treatment.
15. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein the woven
or knitted fabric is dyed.
16. The woven or knitted fabric according to claim 1 comprising
crimped composite filaments and having an air permeability which
increases when the fabric is wetted with water, wherein when a
dried sample is prepared by leaving a test sample of the woven or
knitted fabric to stand for 24 hours in an environment at a
temperature of 20.degree. C. at a humidity of 65% RH, separately a
water-wetted sample is prepared by immersing a test sample of the
woven or knitted fabric in water at a temperature of 30.degree. C.
for 2 hours, pulling up the test sample from the water, holding the
test sample between a pair of filter paper sheets in the ambient
atmospheric air at a temperature of 30.degree. C. at a humidity of
90% RH within 60 seconds after pulling up the test sample, and
leaving the test sample under a pressure of 490 N/m.sup.2 (50
kgf/m.sup.2) for 1 minute to lightly remove water from the test
sample, and the air permeabilities of the dried sample and the
water wetted sample are determined in accordance with JIS L
1096-1998, 6.27.1, Method A (fragile type air permeability testing
machine method), a rate of change in air permeability of the woven
or knitted fabric calculated in accordance with the following
equation: Rate of change (%) in air permeability={[(Air
permeability of water wetted sample)-(Air permeability of dried
sample)]/(Air permeability of dried sample)}.times.100 is 30% or
more.
17. Clothes comprising the woven or knitted fabric according to
claim 1 comprising the crimped composite filaments and having
dimensions which are reversibly enlarged when the fabric is wetted
with water to increase the air permeability thereof.
18. The clothes according to claim 17, wherein at least one of the
flank, the side, the breast, the back and the shoulder of the
clothes is formed from the woven or knitted fabric comprising the
crimped composite filaments.
19. The clothes according to claim 17, wherein each of the portions
of the clothes formed from the woven or knitted fabric comprising
the crimped composite filaments has an area of 1 cm or more.
20. The clothes according to claim 17, wherein the woven or knitted
fabric comprising the crimped composite filaments is selected from
tubular knitted fabrics and mesh-like coarse woven or knitted
fabrics.
21. The clothes according to claim 17, selected from outerwear,
sportswear and underwear.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a woven or knitted fabric
and clothes containing crimped composite filaments and having an
air permeability which increases when the fabric is wetted with
water or, for example, sweat. Particularly, the present invention
relates to a woven or knitted fabric comprising composite filaments
comprising a polyester component and a polyamide component bonded
together in a side-by-side or eccentric core-sheath type structure,
and having manifested crimps. Moreover, the present invention
relates to a woven or knitted fabric and clothes having an air
permeability which reversibly and efficiently increases when the
fabric is wetted with water, in comparison with that upon
drying.
[0002] It has been known that a woven or knitted fabric containing
crimped synthetic filaments can be used for sportswear such as
skiwear, windbreakers and outdoor wear, and outerwear such as
raincoats and men and women's coats, etc.
[0003] However, when the above-mentioned conventional woven or
knitted fabric is wetted with water or, for example, by sweat,
problems that the fabric sticks to the skin to make the wearer feel
uncomfortable, and the drying speed is slow, occur.
[0004] In order to solve the above problems, an air-permeable
self-adjusting type woven or knitted fabric having an air
permeability that is increased by wetting with water and that is
decreased by drying has been proposed. When one wears clothes
prepared from the conventional woven or knitted fabric, and the
clothes are wetted with sweat, the air permeability of the clothes
increases so as to rapidly remove the water remaining in the
clothes to dry the clothes. Moreover, the air permeability of the
clothes decreases after drying to increase the warmth-retaining
effect of the clothes. Therefore, good wearability of the clothes
can always be maintained regardless of whether the wearer sweats or
not.
[0005] For example, Japanese Unexamined Patent Publication (Kokai)
No. 2003-41462 (Patent Reference 1) discloses an air permeable
self-adjusting type woven or knitted fabric comprising composite
filaments (A) in which a modified poly(ethylene terephthalate)
containing a sulfonate group and a nylon are bonded together in a
side-by-side type structure, and filaments (B) the dimensions of
which do not substantially change even when the humidity changes.
Although the air permeability of the woven or knitted fabric is
reversibly increased upon wetting with water in comparison with
that upon drying, an amount of change in air permeability is
practically insufficient.
[0006] Furthermore, Japanese Unexamined Patent Publication (Kokai)
No. 10-77544 (Patent Reference 2) discloses a woven or knitted
fabric comprising 30% by weight or more of synthetic multifilaments
yarn which is formed from a moisture-absorbent polymer (for
example, copolymerized polyester polymers in which a hydrophilic
compound is copolymerized and a polyether ester amide polymers) and
which is one heat-treated so that the yarn has a twist multiplier
of 6,800 to 26,000.
[0007] Still furthermore, Japanese Unexamined Patent Publication
(Kokai) No. 2002-180323 (Patent Reference 3) discloses a woven or
knitted fabric formed from cellulose acetate filaments (having a
percentage of crimp less than 10% at a humidity of 95% RH or more,
and a percentage of crimp of 15 to 20% and a number of crimps of
25/25.4 mm at a humidity of 65%, and a percentage of crimp of 20%
or more at a humidity of 45% RH or less.
[0008] The woven or knitted fabrics disclosed in Patent References
1 and 2 exhibit an air permeability which increases upon absorbing
moisture. However, the extent of the change in air permeability is
practically insufficient and, thus, an air permeable self-adjusting
woven or knitted fabric having a still larger change in air
permeability has been desired.
[0009] Patent Reference 1 Japanese Unexamined Patent Publication
(Kokai) No. 2003-41462
[0010] Patent Reference 2 Japanese Unexamined Patent Publication
(Kokai) No. 10-77544
[0011] Patent Reference 3 Japanese Unexamined Patent Publication
(Kokai) No. 2002-180323
DISCLOSURE OF THE INVENTION
[0012] An object of the present invention is to provide a woven or
knitted fabric comprising crimped composite filaments and having an
air permeability which increases when the fabric is wetted with
water and clothes containing the woven or knitted fabric, the woven
or knitted fabric and clothes having an air permeability which
increases to an adequately high degree for practical use upon being
wetted with water in comparison with that upon drying.
[0013] The woven or knitted fabric of the present invention
comprises a yarn comprising composite filaments formed from a
polyester resin component and a polyamide resin component different
from each other in thermal shrinkage and bonded together in a
side-by-side structure or in an eccentric core-in-sheath structure,
and has crimps manifested by heat treatment applied thereto, the
crimped composite filaments being contained in a content of 10 to
100% by mass in the woven or knitted fabric, and satisfying the
following requirement:
(DC.sub.F-HC.sub.F).gtoreq.10%
wherein DC.sub.F represents a percentage of crimp of a sample of
crimped composite filaments taken from the woven or knitted fabric,
determined by leaving the sample to stand for 24 hours in a test
environment at a temperature of 20.degree. C. at a humidity of 65%
RH to dry and HC.sub.F represents a percentage of crimp of another
sample of the taken crimped composite filaments, determined by
immersing the other sample in water at a temperature of 30.degree.
C. for 2 hours, pulling up the sample from the water, holding the
sample between a pair of filter paper sheets in the ambient
atmospheric air at a temperature of 30.degree. C. at a humidity of
90% RH within 60 sec after pulling up the sample, leaving the
sample under a pressure of 0.69 mN/cm.sup.2 for 5 seconds to
lightly wipe water from the sample, whereby the woven or knitted
fabric exhibit an air permeability which increases when the fabric
is wetted with water.
[0014] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the polyester resin component comprises a modified polyester resin
in which, 5-sodiosulfoisophthalic acid is copolymerized in an
amount of 2.0 to 4.5 molar % based on the content of the acid
component.
[0015] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the yarn comprising the crimped composite filaments has a number of
twists of 0 to 300 turns/m.
[0016] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric contains the crimped composite
filaments and other filaments different from the crimped composite
filaments.
[0017] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the other filaments are selected from non-crimped filaments or
filaments showing a difference in percentage of crimp
DC.sub.F-HC.sub.Fof 10% or less.
[0018] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
when the woven or knitted fabric comprising the crimped composite
filaments is subjected to determination of the stretchability of a
stretchable woven fabric in accordance with JIS L1096, 8.14.1
(Method B, except that the load value applied to a sample woven or
knitted fabric test piece is altered to 1.47 N, where the woven or
knitted fabric is a woven fabric, a stretchability of the woven
fabric in at least one direction selected from the warp direction
and the weft direction is 10% or more, and where the woven or
knitted fabric is a knitted one, the stretchability of the knitted
fabric in at least one direction selected from the course direction
and the wale direction is 10% or more.
[0019] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric comprising the crimped composite
filaments has a multiply structure, and at least one ply thereof
comprises the crimped composite filaments in an amount of 30 to 100
mass % based on the weight of the ply.
[0020] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric is a knitted fabric having a tubular
knitted stitch, and the loop of the tubular knitted stitch is
formed from a yarn comprising the crimped composite filaments and
the other filaments.
[0021] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric is a woven fabric, the yarn containing
composite filaments is a doubled yarn of the crimped composite
filaments and the other or the warp filaments, and the warp and
weft yarns or the warp or weft yarn of the woven fabric is
constituted from a doubled yarn of the crimped composite filaments
and the other filaments.
[0022] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the yarns composed of the crimped composite filaments and the yarn
composed of the other filaments are alternately arranged with one
each other in at least one direction selected from the warp
direction and the weft direction, or in at least one direction
selected from the course direction and the wale direction.
[0023] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
from the crimped composite filaments and the other filaments, a
core-sheath composite yarn is formed, the core portion of the
composite yarn is formed from the crimped composite filaments, and
the sheath portion is formed from the other filaments.
[0024] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the other filaments are selected from polyester filaments.
[0025] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric is one treated with a water-absorbing
agent.
[0026] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric is one treated with a water-repellent
treatment.
[0027] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with water,
the woven or knitted fabric is dyed.
[0028] In the woven or knitted fabric of the present invention
comprising crimped composite filaments and having an air
permeability which increases when the fabric is wetted with
water,
[0029] when a dried sample is prepared by leaving a test sample of
the woven or knitted fabric to stand for 24 hours in an environment
at a temperature of 20.degree. C. at a humidity of 65% RH,
separately a water-wetted sample is prepared by immersing a test
sample of the woven or knitted fabric in water at a temperature of
30.degree. C. for 2 hours, pulling up the test sample from the
water, holding the test sample between a pair of filter paper
sheets in the ambient atmospheric air at a temperature of
30.degree. C. at a humidity of 90% RH within 60 seconds after
pulling up the test sample, and leaving the test sample under a
pressure of 490 N/m.sup.2 (50 kgf/m.sup.2) for 1 minute to lightly
remove water from the test sample, and the air permeabilities of
the dried sample and the water wetted sample are determined in
accordance with JIS L 1096-1998, 6.27.1, Method A, (fragile type
air permeability testing machine method) a rate of change in air
permeability of the woven or knitted fabric calculated in
accordance with the following equation:
Rate of change (%) in air permeability={[(Air permeability of water
wetted sample)-(Air permeability of dried sample)]/(Air
permeability of dried sample)}.times.100
is 30% or more.
[0030] Clothes comprising the woven or knitted fabric of the
present invention comprising the crimped composite filaments and
having dimensions which are reversibly enlarged when the fabric is
wetted with water to increase the air permeability thereof.
[0031] In the clothes of the present invention, at least one of the
flank, the side, the breast, the back and the shoulder of the
clothes is formed from the woven or knitted fabric comprising the
crimped composite filaments.
[0032] In the clothes of the present invention, each of the
portions of the clothes formed from the woven or knitted fabric
comprising the crimped composite filaments has an area of 1
cm.sup.2 or more.
[0033] In the clothes of the present invention, the woven or
knitted fabric comprising the crimped composite filaments is
selected from tubular knitted fabrics and mesh-like coarse woven or
knitted fabrics.
[0034] The clothes of the present invention, are selected from
outerwear, sportswear and underwear.
[0035] The crimped composite filaments contained in the woven or
knitted fabric of the present invention have a characteristic
property that the percentage of crimp of the filaments decreases
10% or more upon wetting with water in comparison with one upon
drying. The woven or knitted fabric containing the crimped
composite filaments therefore exhibits a significantly increased
air permeability upon wetting with water in comparison with one
upon drying. Accordingly, in the case where the woven or knitted
fabric containing a crimped composite filaments of the present
invention is used as a material for forming whole or a part of
outerwear, sportswear or underwear, when the clothes a wearer wears
are wetted with water, for example, due to wearer's sweating, the
air permeability of the clothes increases, and the water component
retained within the clothes is dried and released. When the clothes
are thus adequately dried, the air permeability decreases, and the
warmth retention is improved. The wearability is therefore always
kept excellent, and the clothes contribute to the maintenance of
wearer's good health.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is an explanatory cross-sectional view showing an
example of the cross-sectional profile of a side-by-side type
crimped composite filament contained in the woven or knitted fabric
of the present invention.
[0037] FIG. 2 is an explanatory cross-sectional view showing
another example of the cross-sectional profile of a side-by-side
type crimped composite filament contained in the woven or knitted
fabric of the present invention.
[0038] FIG. 3 is an explanatory cross-sectional view showing still
another example of the cross-sectional profile of a side-by-side
type crimped composite filament contained in the woven or knitted
fabric of the present invention.
[0039] FIG. 4 is an explanatory cross-sectional view showing one
example of the cross-sectional profile of an eccentric
core-in-sheath type crimped composite filament contained in the
woven or knitted fabric of the present invention.
[0040] FIG. 5 is an explanatory front view of clothing (a shirt) in
which a plurality of portions formed from the woven or knitted
fabric of the present invention having an air permeability which
increases when the fabric is wetted with water are arranged on the
front of the clothes.
[0041] FIG. 6 is an explanatory front view of clothing (a shirt) in
which a single portion formed from the woven or knitted fabric of
the present invention having an air permeability which increases
when the fabric is wetted with water is arranged on the front of
the clothes.
[0042] FIG. 7 is an explanatory front view of clothing (a shirt)
having an undersleeve portion and a side portions formed from the
woven or knitted fabric of the present invention having an air
permeability which increases when the fabric is wetted with
water.
[0043] FIG. 8 is a graph showing a change in relative humidity in a
gap between the skin and clothing (a shirt) during wearing of the
present invention (Example 1) and comparative clothes (shirt)
falling outside the scope of the present invention (Comparative
Example 1)), when the clothes are worn and subjected to the
following wearing test procedures containing rest (with wind at 1.5
m/sec).fwdarw.running.fwdarw.rest (without wind).fwdarw.rest (with
wind at 1.5 m/sec).
BEST MODE FOR CARRYING OUT THE INVENTION
[0044] The crimped composite filaments contained in the woven or
knitted fabric of the present invention having an air permeability
which increases when the fabric is wetted with water is formed from
a polyester resin component and a polyamide component, and has a
side-by-side type or an eccentric core-in-sheath type composite
filament structure.
[0045] For a side-by-side type composite filament having, for
example, an approximately circular cross-sectional profile as shown
in FIG. 1, a section 1 comprising a polyester resin component and a
section 2 comprising a polyamide resin component are bonded
together with a side-by-side relationship, and extend along the
longitudinal axis of the composite filament to form an integral
composite filament.
[0046] For a side-by-side type composite filament as shown in FIG.
2, the cross-sectional profile is elliptic, and a section 1 and a
section 2 are preferably bonded together approximately along the
major axis of the elliptic cross-sectional profile.
[0047] For a side-by-side type composite filament having a
cross-sectional profile as shown in FIG. 3, a section 1 comprising
a polyester resin component and a section 2 comprising a polyamide
resin component 2 are bonded together in such a manner that part of
the peripheral face 2a of the section 2 is exposed to the outside
and the remaining peripheral face portion is bonded to the section
1.
[0048] In FIG. 3, the section 1 showing a crescent shape comprises
of a polyester resin component, and the section 2 showing an
approximately elliptic cross-sectional profile comprises a
polyamide resin component. However, the section 1 may also be
composed of a polyamide resin component, and the section 2 may also
be composed of a polyester resin component.
[0049] For an eccentric core-in-sheath type composite filament
having a cross-sectional profile as shown in FIG. 4, a section 2
comprising a polyamide resin component is included in a section 1
comprising a polyester resin component, and the peripheral face of
the section 2 is never exposed to the outside. The central point 1a
of the section 1 never agrees with the central point 2b of the
section 2, and the central points 1a and 2b are apart from each
other.
[0050] The cross-sectional contour of a composite filament
contained in the woven or knitted fabric of the present invention
is not restricted to those as shown in FIGS. 1 to 4. The shape may
be triangular, quadrangular, polygonal, etc., or it may be
internally hollow.
[0051] For a side-by-side type composite filament and an eccentric
core-in-sheath type composite filament, the polyester resin
component and the polyamide resin component are different in
thermal shrinkage from each other. As a result, an amount of
thermal shrinkage of the section 1 and one of the section 2
produced when the composite filament is heated, are different from
each other, and crimp of the composite filament are manifested.
[0052] In the cross-sectional profile of the composite filament in
the present invention, the mass ratio, of the section 1 to the
section 2 that are bonded together, is preferably from 30:70 to
70:30, more preferably from 40:60 to 60:40.
[0053] The polyester resin component comprises a polycondensation
product of an acid component comprising at least one aromatic
dicarboxylic acid, and a diol component comprising at least one
alkylene glycol.
[0054] The acid component preferably comprises terephthalic acid,
as a major component. The diol component preferably contains, as a
major component, ethylene glycol, propylene glycol, butylene
glycol, etc. The polyester resin component preferably comprises, as
a copolymerization component, a compound having at least one
functional group selected from an alkali metal sulfonate group, an
alkaline earth metal sulfonate group and a phosphonium salt group.
That is, the polyester resin component preferably comprises a
modified polyester, for example, a poly(ethylene terephthalate)
copolymer, a poly(propylene terephthalate) copolymer or a
poly(butylene terephthalate) copolymer containing, as a
copolymerization component, an aromatic dicarboxylic acid having,
as a functional group, the sulfonic acid salt group as mentioned
above. The above compounds for copolymerization each having a
sulfonic acid salt group contribute to improving an adhesive
property of the polyester resin component thus obtained to the
polyamide resin component.
[0055] The poly(ethylene terephthalate) copolymer modified with the
copolymerization component containing a sulfonic acid salt group is
particularly preferably used as the polyester resin component of
the crimped composite filament for the woven or knitted fabric of
the present invention, because it has an excellent flexibility and
a low polymer price.
[0056] Examples of the aromatic dicarboxylic acid having a sulfonic
acid salt group include 5-sodium sulfoisophthalic acid and its
ester derivatives and 5-phosphnium isophthalic acid and its ester
derivatives. Moreover, examples of the hydroxyl compound containing
a sulfonate group include sodium p-hydroxybenzenesulfonate. Among
these compounds, 5-sodium sulfoisophthalic acid is preferably used.
The content of the above copolymerization component is preferably
from 2.0 to 4.5 molar % based on a molecular amount of the acid
component of the polyester polymer containing the copolymerization
component. When the content of the copolymerization content is less
than 2.0 mol %, the resultant composite filaments exhibits a
sufficient crimping property, while the section composed of the
polyester resin component and the section composed of the polyamide
resin component may be separated at the interface between them from
each other. Moreover, where the content of the above
copolymerization component exceeds 4.5 molar %, and when the
resultant undrawn composite filaments are drawn and heat-treated,
crystallization of the section composed of the resultant polyester
resin component insufficiently proceeds, and thus it becomes
necessary to increase the drawing and heat treatment temperature,
and the increased temperature causes breakages, of the resultant
yarns, which often occur during the drawing and heat treatment
procedures.
[0057] There is no restriction on the type of the polyamide resin
used as the polyamide resin component as long as it has an amide
bond in the principal chain and it has fiber forming property.
Examples of the polyamide resin include nylon 4, nylon 6, nylon 66,
nylon 46 and nylon 12. Among these resins, nylon 6 and nylon 66 are
preferably used in the present invention in view of the excellent
flexibility, its relatively low polymer price and the high
stability in production step of the polyamide resin.
[0058] The polyester resin component and the polyamide resin
component may be respectively, independently from each other and
optionally contain at least one type of additives selected from
pigments, delustering agents, stain-proofing agents, fluorescent
brighteners, flame retardants, stabilizers, antistatic agents,
light-resistant agents and UV absorbers.
[0059] There is no specific restriction on the thickness of
individual filaments in the composite filaments and the number of
individual filaments contained in one yarn. However, the thickness
of the individual filaments is preferably in the range of from 1 to
10 dtex, more preferably from 2 to 5 dtex. The number of composite
filaments contained in one yarn of the composite filaments is
preferably from 10 to 200, more preferably from 20 to 100.
[0060] Furthermore, in the composite filaments contained in the
woven or knitted fabric of the invention, the polyamide resin
section formed from the polyamide resin component has a higher
thermal shrinkage and a higher moisture absorption self-elongation
than those of the polyester resin section formed from the polyester
resin component.
[0061] Consequently, when the composite filaments usable for the
present invention having a side-by-side or eccentric core-in-sheath
type composite filament structure are heated, the polyamide resin
section shrinks greater than the polyester resin section. As a
result, the composite filament manifests a crimped structure
wherein the resin section having a larger shrinkage amount is
situated inside, and the resin section having a smaller shrinkage
amount is situated outside. When the yarn containing a non-crimped
composite filament is heated to manifest crimps in the resultant
composite filaments, the resultant yarn containing crimped
composite filaments has a higher bulkiness and a shorter apparent
yarn length than those of the non-crimped composite filament
yarn.
[0062] When a crimped composite filament used in the present
invention is wetted with water, the polyamide resin section in the
crimped composite filament absorbs a larger amount of water than
that of the polyester resin section, and exhibits a larger
self-elongation. (In general, the self-elongation of the polyester
resin section caused by water wetting is close to zero.) As a
result, the percentage of crimp of a water-wetted crimped composite
filament becomes lower than that of a dried crimped composite
filament; the apparent length of the water-wetted crimped composite
filament becomes greater than that of the dried crimped composite
filament. Moreover, when the water-wetted crimped composite
filament is dried, the polyamide resin section is dehydrated and
shrunk. However, because the polyester resin section has
substantially no dimensional change, the percentage of crimp of the
dried crimped composite filament recovers to the initial one, and
the apparent length thereof recovers to the initial one.
[0063] As explained above, in the crimped composite filament
contained in the woven or knitted fabric of the invention, the
percentage of crimp decreases upon being wetted with water, and the
apparent length of the filament increases. The percentage of crimp
and the apparent length of the crimped composite filament recover
the initial ones upon drying. In the woven or knitted fabric formed
from yarns containing crimped composite filaments having the above
properties, the percentage of crimp of the crimped composite
filaments decreases upon being wetted with water. As a result, the
length of the crimped composite filament-containing yarn increases;
a gap between yarns in the woven or knitted fabric increases; the
area of the fabric increases; and the air permeability of the
fabric increases.
[0064] The air permeability of the woven or knitted fabric can be
determined in accordance with JIS L 1096-1998, 6.27.1. A Method
(Fragile type air permeability testing machine method).
[0065] In the woven or knitted fabric containing a crimped
composite filaments of the present invention, it is important that
the air permeability upon being wetted with water be higher than
that upon drying. Preferably the air permeability upon being wetted
with water is 30% or more, more preferably 80 to 500% higher than
that upon drying.
[0066] A change (%) in air permeability is calculated from the
following equation:
change (%) in air permeability=[(air permeability of a water wetted
sample)-(air permeability of a dried sample)]/(air permeability of
a dried sample).times.100
wherein the dried sample is prepared by leaving a test sample of
the woven or knitted fabric to stand for 24 hours in an environment
at a temperature of 20.degree. C. at a humidity of 65% RH,
separately the water wetted sample is prepared by immersing a test
sample of the woven or knitted fabric in water at a temperature of
30.degree. C. for 2 hours, pulling up the test sample from the
water, holding the test sample between a pair of filter paper
sheets in the ambient air at a temperature of 30.degree. C. at a
humidity of 90% RH within 60 seconds after pulling up the test
sample, and leaving the test sample under a pressure of 490
N/cm.sup.2 (50 kgf/m.sup.2) for 1 minute to lightly remove water in
the test sample.
[0067] For clothes having a rate of change in air permeability of
less than 30%, the air permeability of the clothes become
insufficient when the wearer wears the clothes containing the
water-wetted woven or knitted fabric and sweats. The clothes then
cause the wearer to feel increased stuffiness or sultriness.
[0068] The woven or knitted fabric of the present invention
contains the crimped composite filaments in a content of 10 to 100
mass %, and the content is preferably from 40 to 100 mass %. When
the content is less than 10 mass %, the effect of the crimped
composite filaments, namely, a reversible change between an
increase and decrease in air permeability caused by wetting with
water and drying of the woven or knitted fabric thus obtained
becomes insufficient.
[0069] For the woven or knitted fabric of the present invention,
the crimped composite filament is contained in yarns for forming
the woven or knitted fabric. The percentage of crimp of the crimped
composite filaments decreases upon wetting with water, whereby the
apparent length of the yarn containing the crimped composite
filament increases. As a result, the area of the woven or knitted
fabric increases so as to increase the openings between yarns.
Consequently, the air permeable opening area and the air
permeability increase.
[0070] In order to enable the crimped composite filament-containing
yarn to increase or decrease the apparent length thereof with a
high efficiency, in response to a decrease or an increase of the
crimping property of the crimped composite filaments and, thereby,
the air permeability of the woven or knitted fabric to increase or
decrease with high efficiency, the yarn is preferably a non-twisted
or soft twisted one having a number of twists of 0 to 300 turns/m,
particularly more preferably a non-twisted yarn. When the number of
twists exceeds 300 turns/m, the resultant crimped composite
filaments within the yarn mutually restrict the deformation
thereof. Thus, a change in the percentage of crimp of the composite
filaments, upon being wetted with water or drying, is also
restrained and a change in the apparent length of the yarn is also
restricted. Therefore, the change in the air permeability of the
woven or knitted fabric may be also restricted.
[0071] In addition, a yarn containing the crimped composite
filaments may be subjected to an air interlacing and/or false twist
and crimping treatment. However, in this case, a number of
interlacing among the filaments in the yarn is preferably from
about 20 to 60/m.
[0072] The yarn containing crimped composite filaments optionally
contains other type of filaments than the crimped composite
filaments. The other filaments can be selected from non-crimped
filaments and filaments having a difference in percentage of crimp
DC.sub.F-HC.sub.F of less than 10%. There is no specific limitation
to the type of a polymer for forming the other filaments. Examples
of the polymer include polyesters, for example, poly(ethylene
terephthalate), poly(trimethylene terephthalate) and poly(butylene
terephthalate), polyamides, for example, nylon 6 and nylon 66,
polyolefins, for example, polyethylene and polypropylene, acrylic
polymers, p- or m-aramid polymers and modified polymers of the
above mentioned polymers. Moreover, the other filaments may be
selected from such filaments appropriate for clothes as natural
fibers, regenerated fibers and semi-synthetic fibers. Among these
filaments, filaments of polyester, for example, poly(ethylene
terephthalate), poly(propylene terephthalate), poly(butylene
terephthalate) or modified polyester in which the above
copolymerization component is copolymerized are appropriate in view
of the dimensional stability upon being wetted with water and the
compatibility (filament-combinability, mixed knittability or mixed
weavability and dyeability) with the composite filaments. Moreover,
there are no specific restrictions to individual filament thickness
of the other filaments and the number of individual filaments per
yarn. However, in order to enhance the moisture absorption of the
woven or knitted fabric and increase the air permeability of the
fabric upon moisture-uptaking, the individual filament thickness is
preferably from 0.1 to 5 dtex (more preferably 0.5 to 2 dtex), and
the number of the individual filaments per yarn is preferably from
20 to 200 (more preferably from 30 to 100). In addition, other
filaments may be air interlaced and/or conventionally false twisted
and crimped so that the number of interlacing becomes about 20 to
60/m.
[0073] In the woven or knitted fabric of the present invention, the
crimped composite filaments and the other filaments may
respectively constitute at least one type of yarns, and these yarns
may be mixed woven or knitted. Alternatively, the crimped composite
filaments and the other yarn may constitute together a combined
yarn, and air combining may be employed to form the combined yarn.
Moreover, the crimped composite filaments yarn and the other
filaments yarn may constitute together a doubled and twisted yarn
or a doubled yarn, or they may also constitute a composite false
twisted crimped yarn.
[0074] There is no restriction to the woven or knitted structures
and the number of woven or knitted plies in the woven or knitted
fabric of the present invention. The woven or knitted structures
include, for example, weave structures such as plain weave, twill
weave and satin weave, and a knitting stitch such as plain
knitting, circular rib knitting, a tuck float knitting, plating
stitch, a dembigh stitch and a half tricot stitch. Moreover, the
above woven or knitted structures may each include a single ply
structure and a multi-ply structure having two or more plies.
[0075] For the woven or knitted fabric of the present invention, in
order to ensure the movability and deformability
(crimp-changeability) of the crimped composite filaments in the
woven or knitted fabric, the crimped composite filaments preferably
have stretchability in the warp direction and/or weft direction.
The stretchability is preferably 10% or more (more preferably 20%
or more, still more preferably from 25 to 150%).
[0076] Next, for the woven or knitted fabric of the present
invention, the composite filaments contained in the woven or
knitted fabric of the invention have a crimped structure formed by
manifesting their latent crimpability. It is important that the
composite filaments satisfy the requirement represented by the
following expression:
DC.sub.F-HC.sub.F.gtoreq.10 (%) (preferably 50
(%).gtoreq.DC.sub.F-HC.sub.F.gtoreq.10
wherein DC.sub.F (%) is a percentage of crimp of the composite
filaments upon drying, and HC.sub.F (%) is a percentage of crimp of
the composite filaments upon being wetted with water. When
DC.sub.F-HC.sub.F is less than 10%, the air permeability of the
resultant fabric upon being wetted with water might not efficiently
increase, unpreferably, in comparison with that upon drying.
[0077] The percentage crimp of a crimped composite filament in the
woven or knitted fabric herein is determined by the following
procedure. First, a woven or knitted fabric is left to stand in an
atmosphere at 20.degree. C. and 65% RH for 24 hours. Small samples
(n=5) each having dimensions of 30 cm.times.30 cm are cut out from
the conditioned woven or knitted fabric in the same direction
thereof. Composite filaments are taken out from each small sample.
A load of 1.76 mN/dtex (200 mg de) is applied to the composite
filament sample, and the filament length L0f is determined. One
minute after removal of the load, a load of 0.0176 mN/dtex (2
mg/de) is applied to the filament, and the filament length L1f is
determined. Moreover, the composite filament sample is immersed in
water at 30.degree. C. for 2 hours, and then taken out. The sample
is held between a pair of filter paper sheets within 60 sec after
taking out, in the ambient air atmosphere at 30.degree. C. and 90%
RH, and then a pressure of 0.69 mN/cm.sup.2 is applied to the
sample for 5 sec to lightly wipe out water. A load of 1.76 mN/dtex
(200 mg de) is applied to the sample, and the filament length L0f'
is determined. One minute after removal of the load, a load of
0.0176 mN/dtex (2 mg/de) is applied to the sample, and the filament
length L1f' is determined. The percentage of crimp DC.sub.F (%)
upon drying and the percentage of crimp HC.sub.F (%) upon being
wetted with water are calculated from the following formula.
Percentage of crimp DC.sub.F (%) upon
drying=((L0f-L1f)/L0f).times.100
Percentage of crimp HC.sub.F (%) upon being wetted with
water=((L0f'-L1f')/L0f').times.100
[0078] The difference (DC.sub.F-HC.sub.F) (%) is calculated from
the above DC.sub.F and HC.sub.F values. In addition, n is then 5,
and the average values are calculated.
[0079] The woven or knitted fabric of the invention may be
subjected to water absorption treatment. When the woven or knitted
fabric is subjected thereto, the air permeability of the fabric is
likely to be improved even with a small amount of sweat. A
conventional water absorption treatment is satisfactory for such a
treatment. The following procedure is exemplified as a preferred
water absorption treatment: a water absorption treatment agent such
as a poly(ethylene glycol diacrylate) or its derivative, or a
poly(ethylene terephthalate)-poly(ethylene glycol) copolymer is
allowed to adhere in an amount of 0.25 to 0.50% by weight based on
the weight of the woven or knitted fabric to the woven or knitted
fabric. Examples of the water absorption treatment method include a
bath treatment method in which a water absorption treatment agent
is added to a dyeing solution during dyeing, and a dipping method
in which a woven or knitted fabric is dipped in a water absorption
treatment solution and squeezed with a mangle before a dry-heat
final set, a gravure coating method and screen printing method.
[0080] Furthermore, the woven or knitted fabric of the present
invention may be subjected to a water-repellent treatment. The
water-repellent treatment may be a conventional one. For example,
such a method as described in Japanese Patent Publication No.
3133227 and Japanese Examined Patent Publication (Kokoku) No.
4-5786 is appropriate. That is, the method comprises mixing a
commercially available fluororesin water repellant (e.g., trade
name of Asahi Guard LS 317, manufactured by Asahi Glass Co., Ltd.)
used as a water repellant with a melamine resin (optional
component) and a catalyst to form a treatment agent containing
about 3 to 15% by weight of the water repellant, and treating the
surface of the woven or knitted fabric with the treatment agent at
a pickup ratio of about 50 to 90%. Examples of the method of
treating the surface of the woven or knitted fabric with the
treatment agent include a padding method and a spraying method. Of
these methods, the padding method is most preferred because the
treatment agent penetrates into the interior of the woven or
knitted fabric.
[0081] In addition, the pickup ratio is a proportion (%) of a
weight of the treatment agent to a weight of the woven or knitted
fabric (prior to imparting the treatment agent).
[0082] When the water repellency of the woven or knitted fabric
after a water repellent treatment is evaluated in accordance with
JIS L1092 6.2 (Spray Test), it is preferably evaluated to point 4
or more, more preferably point 5 (highest point).
[0083] For the water-repellent woven or knitted fabric thus
obtained, because the percentage of crimp of the composite
filaments contained in the woven or knitted fabric is efficiently
decreases upon wetting with water, the yarn length of the composite
filaments increases. As a result, openings in the woven or knitted
fabrics are made large to improve the air permeability of the
fabric. On the other hand, because the percentage of crimp ratio of
the composite filaments increases upon drying, and a yarn length of
the composite filaments is decreased. As a result, the openings in
the woven or knitted fabric are made small to decrease the air
permeability of the fabric.
[0084] The woven or knitted fabric of the present invention may be
dyed. The conditions of dyeing will be explained in detail.
[0085] The woven or knitted fabric in the present invention
includes the following embodiments: (1) a woven or knitted fabric
having a multiply structure with at least two plies, and at least
one ply containing the crimped composite filaments in an amount of
30 wt. % or more based on the total weight of the filaments from
which the ply is formed; (2) a knitted fabric having a tubular
knitting structure in which the loops of the tubular stitch are
formed from yarns containing the composite filaments and the other
filaments; (3) a woven fabric formed from warp yarns and/or a weft
yarns of the weave structure, in which yarns the composite
filaments and the other filaments are combined in parallel with
each other; (4) a woven or knitted fabric wherein the composite
filaments yarns and the other filaments yarns are used as
constituent yarns, and alternately arranged with every one yarn or
every a plurality of yarns (5) a woven or knitted fabric containing
the composite filaments and the other filaments as a core-in-sheath
type composite yarn in which the composite filaments are situated
in the core portion and the other filaments are situated in the
sheath portion.
[0086] Moreover, for a woven or knitted fabric containing the
composite filaments and other filaments, when a filament length A
of the composite filaments and a filament length B of the other
filaments are in the relationship i A<B upon drying, the air
permeability of the fabric preferably increases upon being wetted
with water. Conversely, when A>B or A=B, the air permeability of
the fabric may not increase upon being wetted with water, for the
following reasons: when the percentage of crimp of the composite
filaments decreases and the composite filaments are elongated by
being wetted with water, the other filaments have no allowance for
the elongation and cannot be adapted to the elongation of the
composite filaments; as a result, the percentage of openings in the
woven or knitted fabric decreases.
[0087] Herein, the filament length is determined by the following
measurement. First, a woven or knitted fabric is left to stand in
an atmosphere at 20.degree. C. and 65% RH for 24 hours. Small
samples (n=5) each having dimensions of 30 cm.times.30 cm are cut
out from the conditioned woven or knitted fabric. One composite
filament yarn and another different filament yarn are taken out of
each sample. A filament length A (mm) of the composite filaments
yarn and a filament length B (mm) of the other different filaments
yarn are determined. During the determination, a load of 1.76
mN/dtex (200 mg/de) is applied to the sample filament yarn when the
yarn is non-elastic, and a load of 0.0088 mN/dtex (1 mg/de) is
applied to the sample filament yarn when the yarn is elastic.
Herein, the composite filaments yarn and the other different
filaments yarn must be taken out of the small sample in the same
direction. For example, when the composite filaments yarn is taken
out of the warp yarns (or weft yarns) of the woven or knitted
fabric, the other different filaments yarn must also be taken out
of the warp yarns (or weft yarns). Moreover, when composite yarns
are formed from the composite filaments yarn and the other
different filaments yarn, and the woven or knitted fabric is formed
from the composite yarns, the composite yarns are taken out of the
cut small sample (30 cm.times.30 cm) (n=5), and the composite
filaments yarn and the other different filaments yarn are further
taken out of the composite yarn. Measurements are similarly made on
the taken-out yarns.
[0088] As explained above, in order to make a difference between a
length A of the composite filaments yarn and a length B of the
other different filaments yarn, the following methods are
exemplified: when the woven or knitted fabric is woven or knitted
from the composite filaments yarn and the other different filaments
yarn, a method comprising adjusting the shrinkage of the other
different filaments yarn in boiling water to 15% or less (more
preferably 10% or less); and a method in which during conjugating
the composite filaments yarn with the other different filaments
yarn, the other different filaments yarn is overfed to the
conjugating procedure.
[0089] In order to ensure the movability of composite filaments in
the woven or knitted fabric of the present invention, the basis
mass of the fabric is preferably adjusted to 300 g/m.sup.2 or less
(more preferably 100 to 250 g/m.sup.2).
[0090] The woven or knitted fabric of the present invention can be
easily produced by, for example, the following process.
[0091] A modified polyester having an intrinsic viscosity of 0.30
to 0.43 (determined at 35.degree. C. with o-chlorophenol used as a
solvent), in which 5-sodium sulfoisophthalic acid is copolymerized
in an amount of 2.0 to 4.5 mol %, and a polyamide having an
intrinsic viscosity of 1.0 to 1.4 (determined at 30.degree. C. with
m-cresol used as a solvent) are melt-spun together through a
spinneret for a side-by-side or eccentric core-sheath composite
filaments. It is particularly important that the intrinsic
viscosity of the polyester resin component be 0.43 or less. When
the intrinsic viscosity of the polyester resin component is higher
than 0.43, the viscosity of the polyester component increases, and
thus the physical properties of the resultant composite filaments
become close to those of the yarns formed from only the polyester
yarns, and thus the desired woven or knitted fabric in the present
invention cannot be obtained unpreferably. Conversely, when the
intrinsic viscosity of the polyester resin component is less than
0.30, the melt viscosity of the resin becomes too low and thus the
spinnability of the resin decreases and fluff formation takes place
often. As a result, the quality and the productivity might
decrease.
[0092] A spinneret as disclosed in, for example, FIG. 1 in Japanese
Unexamined Patent Publication (Kokai) No. 2000-144518, wherein the
extrusion holes of the high viscosity side are separated from those
of the low viscosity side, and the extrusion linear speed of the
high viscosity side is lowered (cross-sectional area of the
extrusion holes being increased). Moreover, a molten polyester is
preferably passed through the high viscosity side extrusion holes,
and a molten polyamide is preferably passed through the low
viscosity side extrusion holes and extruded melt flows are cooled
and solidified. The weight ratio of the polyester component to the
polyamide component is, as explained above, preferably from 30:70
to 70:30 (more preferably from 40:60 to 60:40).
[0093] Furthermore, a separate drawing system wherein melt
composite spinning is conducted, the spun yarn is wound once, and
the wound yarn is drawn, may be adopted. A direct drawing system
wherein the spun yarn is drawn and heat treated without winding may
also be adopted. A conventional spinning and drawing conditions may
be adopted for the process. For example, when a direct drawing
system is conducted, a yarn is spun at a speed of about 1,000 to
3,500 m/min, and the spun yarn is successively drawn and wound at
temperatures of 100 to 150.degree. C. The draw ratio is suitably
selected so that the composite filaments finally obtained exhibit
an elongation at break of 10 to 60% (preferably 20 to 45%) and a
tensile strength at break of about 3.0 to 4.7 cN/dtex.
[0094] Herein, the composite filaments preferably satisfy the
requirements (1) and (2), simultaneously.
[0095] (1) The percentage of crimp DC of the composite filaments
upon drying is from 1.5 to 13% (preferably from 2 to 6%).
[0096] (2) A difference (DC-HC) between the percentage of crimp DC
upon drying and the percentage of crimp HC upon wetting with water
of composite filaments is 0.5% or more (preferably 1 to 5%).
[0097] The term "upon drying" designates the state of a sample
having been allowed to stand in an environment at a temperature of
20.degree. C. at a humidity of 65% RH for 24 hours. On the other
hand, the term "upon being wetted with water" designates the state
of a sample that is immediately after immersing the sample in water
at 30.degree. C. for 2 hours. Numerical values obtained by the
methods explained below will be used as the percentage of crimp DC
upon drying and the percentage of crimp HC upon being wetted with
water, respectively.
[0098] First, using a rewinding frame having a frame peripheral
length of 1.125 m, a composite yarn is wound at a constant speed
under a load of 49/50 mN.times.9.times.total tex (0.1
gf.times.total denier) applied to the yarn to form a small hank
having a number of winding of 10 times. The small hank is twisted
to form a double ring, and the twisted hank is treated in boiling
water for 30 minutes under an initial load of 49/2,500
mN.times.20.times.9.times.total tex (2 mg.times.20.times.total
denier) applied to the hank. After the boiling water treatment, the
treated hank is dried in a drier at 100.degree. C. for 30 minutes,
and then further treated with a dry heat at 160.degree. C. for 5
minutes while the initial load is kept applied. After dry heat
treatment, the initial load is removed, and the hank is allowed to
stand in an environment at 20.degree. C. and 65% RH for 24 hours.
The initial load and a heavy load of 98/50
mN.times.20.times.9.times.total tex (0.2 gf.times.20.times.total
denier) are then applied to the hank, and the hank length L0 is
determined. The heavy load alone is immediately removed, and the
hank length L1 is determined at a stage of 1 minute after the load
removal. Moreover, the hank is immersed in warm water at 20.degree.
C. for 2 hours while the initial load is kept applied. The hank is
then taken out, and a pressure of 0.69 mN/cm.sup.2 (70
mgf/cm.sup.2) is applied to the hank with a filter paper sheet so
that water is lightly wiped out. The initial load and the heavy
load are then applied, and the hank length L0' is determined. The
heavy load alone is then immediately removed, and the hank length
L1' is determined at a stage of 1 minute after removal of the load.
The percentage of crimp DC (%) upon drying, the percentage of crimp
HC (%) upon being wetted with water and the difference (DC-HC) (%)
between the percentage of crimp upon drying and that upon being
wetted with water are calculated from the above determined
numerical values using the following calculation expression:
Percentage of crimp DC (%) upon drying=((L0-L1)/L0).times.100
Percentage of crimp HC (%) upon being wetted with
water=((L0'-L1')/L0').times.100
[0099] The percentage of crimp HC of the composite filaments during
wetting with water is preferably in the range of from 0.5 to 10.0%
(more preferably from 1 to 3%).
[0100] When the percentage of crimp DC of the composite filaments
upon drying is less than 1.5%, a change in percentage of crimp upon
being wetted with water decreases, and thus, a change in the air
permeability of the woven or knitted fabric may decrease.
Conversely, when the percentage of crimp DC of the woven or knitted
fabric upon drying is greater than 13%, the crimp is hardly changed
upon being wetted with water because the crimping is too strong,
and thus an extent of change in the air permeability of the woven
or knitted fabric may also decrease. Moreover, when a difference
(DC-HC) between the percentage of crimp DC upon drying and the
percentage of crimp HC upon being wetted with water of the woven or
knitted fabric is less than 0.5%, an extent of a change in the air
permeability of the woven or knitted fabric may also decrease.
[0101] Next, the woven or knitted fabric is prepared from the
composite filaments alone or from the composite filaments and other
filaments in combination, and the crimp of the composite filaments
is manifested by heat treatment, for example, such a dyeing
treatment.
[0102] Herein, it is important, as explained above, that in the
production of a woven or knitted fabric, the composite filaments be
woven or knitted in an amount of 10 wt. % or more (more preferably
40 wt. % or more), on the basis of the weight of the woven or
knitted fabric. Moreover, there is no specific restriction to the
woven or knitted structure, and it may be appropriately selected
from the afore-mentioned structures.
[0103] The dyeing temperature is preferably from 100 to 140.degree.
C. (more preferably from 110 to 135.degree. C.). The holding time
at the highest temperature during dyeing procedure is preferably
from 5 to 40 minutes. When the woven or knitted fabric is dyed
under the above-mentioned conditions, a difference in thermal
shrinkage between the polyester component and the polyamide
component in the composite filaments manifests the crimps thereof.
Selection of the above-mentioned polymers as the polyester
component and the polyamide component enables the resultant
composite filaments take a crimped structure during the
manifestation of the crimp in which the polyamide component is
located inside portions of the crimps.
[0104] After the dyeing is completed, the dyed woven or knitted
fabric is usually subjected to a dry-heat final-set procedure. The
dry-heat final-set temperature is preferably from 120 to
200.degree. C. (more preferably from 140 to 180.degree. C.), and
the first heat-set time is preferably from 1 to 3 minutes. When the
dry-heat final-set temperature is lower than 120.degree. C.,
wrinkles generated during dyeing might remain. Moreover, the
dimensional stability of finished articles may be insufficient.
Conversely, when the dry heat final set temperature is higher than
200.degree. C., the crimp of the composite filaments manifested
during dyeing may be decreased, and the filaments may be hardened
so as to cause the hand of the fabric to be stiff.
[0105] The woven or knitted fabric of the present invention may be
subjected to various treatments, for example, conventional raising,
UV-ray shielding or imparting functions with agents such as
antibacterial agents, deodorants, moth-proofing agents, luminous
agents, retroreflective agents, negative-ion-generating agents and
water absorption agents.
[0106] The woven or knitted fabric of the present invention can be
used for forming at least a part of the clothes, for example
outerwear, sportswear and underwear by utilizing the characteristic
that the percentage of crimp significantly decreases upon wetting
with water the crimped composite filaments contained therein and
consequently increasing the air permeability thereof.
[0107] The clothes of the present invention contain the woven or
knitted fabric of the invention containing crimped composite
filaments and having an air permeability that increases upon being
wetted with water, and are characterized in that the dimensions of
the clothes are reversibly enlarged upon being wetted with water to
increase the air permeability and exhibit a ventilation effect.
[0108] The clothes of the present invention include outerwear,
sportswear and underwear.
[0109] In a preferred embodiment of the clothes of the present
invention, the clothes have a portion having no dimensional change
when wetted with water, and a portion that reversibly increases the
dimensions (reversibly increases the area) upon being wetted with
water. In this embodiment, because the enlargement of the area
caused upon being wetted with water is partially effected, neither
the dimensions of the clothes as a whole nor the gap between the
clothes and the skin of the wearer is excessively enlarged. That
is, when a wearer puts the clothes of the above embodiment on and
sweats, a portion having dimensions (area) increased upon being
wetted with sweat bulges outside so that an air gap between the
skin of the wearer and the portion increases to increase the air
permeability of the wetted portion and the ventilation effect.
[0110] For the clothes of the present invention, a portion having
no dimensional change upon being wetted with water designates a
portion that has a change in area caused by water wetting of less
than 5%, and a portion having a dimensional change when wetted with
water designates a portion having a change in area caused upon
being wetted with water of 5% or more. A change in area of a
clothes portion is determined by the following method.
[0111] A woven or knitted fabric is allowed to stand in an
environment at 20.degree. C. and 65% RH (hereinafter referred to as
during drying) for 24 hours, and a sample (square sample, 20 cm
(warp).times.20 cm (weft)) is cut out in the same direction as the
woven or knitted fabric. The area (cm.sup.2) of the sample is
defined as an area upon drying. On the other hand, the sample is
immersed in water at 30.degree. C. for 5 minutes (hereinafter
referred to as upon being wetted with water), pulled up, and then
held between 2 filter paper sheets within 60 sec after pulling up.
A pressure of 490 N/m.sup.2 (50 kgf/m.sup.2) is applied for 1
minute to remove a water component present among filaments. The
area (cm.sup.2) of the wetted sample is then determined. When the
area is reduced by water wetting the sample, the case is also
included in the case in which "the sample has no dimensional change
upon being wetted with water."
change in area (%)=((area during water wetting)-(area during
drying))/(area during drying).times.100
[0112] There is no specific restriction to the type of the
embodiments of the clothes in the present invention. Examples of
the woven or knitted fabric forming a portion that has no
dimensional change upon being wetted with water include organic
natural fibers, for example, cotton, wool and hemp fibers, organic
synthetic fibers, for example, polyester fibers, nylon fibers and
polyolefin fibers, organic semi-synthetic fibers, for example,
cellulose acetate fibers and organic regenerated fibers, for
example, viscose rayon fibers.
[0113] Among the fibers, polyester fibers are appropriate in view
of the fiber strength and handleability. The polyester fibers are
produced from a dicarboxylic acid component and a diglycol
component. It is preferred to mainly use terephthalic acid as the
dicarboxylic acid component. It is preferred to mainly use, as the
diglycol component, at least one alkylene glycol selected from
ethylene glycol, trimethylene glycol and tetramethylene glycol.
Moreover, the polyester may be made to contain a third component in
addition to the dicarboxylic acid component and the glycol
component. Examples of the third component include a cationic
dye-dyeable anionic component, for example, sodiosulfoisophthalic
acid, a dicarboxylic acid other than terephthalic acid, for
example, isophthalic acid, naphthalenedicarboxylic acid, adipic
acid, and sebacic acid, and a glycol compound other than an
alkylene glycol such as diethylene glycol, poly(ethylene glycol),
bisphenol A and bisphenolsulfone. At least one of these compounds
may be used.
[0114] Filaments having no dimensional change upon being wetted
with water may optionally contain at least one of the following
agents or materials: delustering agents (titanium dioxide),
micropore-forming agents (metal salt of organic sulfonic acid),
anti-coloring agents, thermal stabilizers, flame retardants
(diantimony trioxide), fluorescent brighteners, coloring pigments,
antistatic agents (metal salt of a sulfonic acid), a hygroscopic
agents (poly(oxyalkylene glycol)), antibacterial agents and other
inorganic particles.
[0115] There is no specific restriction to the shape of filaments
having no dimensional change upon being wetted with water. It may
be either filaments (multifilaments) or a staple fiber. In view of
obtaining a high flexibility, multifilaments are preferred.
Moreover, the filaments may be ones false twisted and crimped,
twisted or air interlaced. There is no specific limitation to the
thickness of the filaments. However, in view of obtaining a high
flexibility, the filaments preferably have an individual filament
thickness of 0.1 to 3 dtex, a number of filaments of 20 to 150 and
a total thickness of 30 to 300 dtex. There is no specific
restriction to the cross-sectional profile of the individual
filament and the filament may have a triangular, flat, cross,
hexagonal or hollow cross-sectional shape, in addition to a regular
circular cross-sectional shape.
[0116] There is no specific restriction to the structure of the
woven or knitted fabric that has no dimensional change even when
wetted with water, and conventional ones may be used. Examples of
the weave structure of the woven fabric include three foundation
weaves, namely plain weave, twill weave and satin weave, derivative
weaves, for example, derivative twill weave, one side double
structures, for example, warp double weave and weft double weave,
and warp velvet weave. The type of the knitted fabric may be a weft
knitted fabric or a warp knitted fabric. Preferred examples of the
weft knitted stitch include a plain stitch, a rubber stitch, a
double face stitch, a purl stitch, a tuck stitch, a float stitch, a
half cardigan rib stitch, a lace stitch and a plating stitch.
Examples of the warp knitting stitch include a single dembigh
stitch, a single atlas stitch, a double cord stitch, a half tricot
stitch, a fleecy stitch and a jacquard stitch.
[0117] In the above embodiments of the clothes of the present
invention, portions, the dimensions of which are reversibly
enlarged upon wetting with water, are locally arranged, and the
other portions are formed from a woven or knitted fabric the
dimensions of which are not changed even upon wetting with water.
Sites where the wearer sweats relatively much are appropriate as
the portions the dimensions of which are reversibly enlarged upon
wetting with water. Examples of the appropriate portions are as
follows: woven or knitted fabric portions 6 arranged in a front 5
schematically shown in FIG. 5; a woven or knitted fabric portion 8
located in a breast 7 schematically shown in FIG. 6; and a woven or
knitted fabric portion 11 arranged in at least one portion of the
side 9, the back (not shown) and the portions 10 below the sleeves
schematically shown in FIG. 7. Preferred areas of woven or knitted
fabric portions the dimensions of which are reversibly enlarged
upon wetting with water are 1 cm.sup.2 or more per woven or knitted
fabric portion of the clothes and 500 to 10000 cm.sup.2 in total.
It is appropriate that the ratio of a total area of the woven or
knitted fabric portions to a total area of the clothes be from 5 to
70%. When the area ratio is smaller than 5%, the space volume
between the clothes and the skin upon wetting with water is not
sufficiently large, and thus a sufficient ventilation effect cannot
be obtained sometimes. Conversely, when the area ratio is larger
than 70%, the dimensions of the clothes as a whole may be changed
upon being wetted with water.
[0118] The woven or knitted fabric of the present invention is used
as a fabric for forming a portion of the clothes the dimensions of
which are reversibly enlarged upon being wetted with water.
[0119] There are no specific restrictions to the woven or knitted
fabric structure and a number of plies of the woven or knitted
fabric the dimensions of which are reversibly enlarged by wetting
with water, for the clothes. The following are appropriately
exemplified as the woven or knitted fabric: woven structures, for
example, plain weave, twill weave and satin, and knitting stitch,
for example, plain knitting stitch, an interlock stitch, a circular
rib fabric, a tuck float fabric, a plating stitch, a dembigh stitch
and a half tricot stitch. A tubular knitted or a mesh-like woven or
knitted fabric is particularly preferred.
[0120] For a change in dimensions of the above-mentioned portions,
the change in the area is preferably 10% or more, more preferably
from 15 to 30%. When the change in the area is less than 10%, a
space volume between the clothes and the skin upon wetting with
water does not increase so much, and the ventilation effect may be
insufficient. The woven or knitted fabric for forming the portions
having a dimensional change upon wetting with water can be easily
obtained by, for example, the production process explained
above.
[0121] The woven or knitted fabric for clothes of the present
invention is preferably subjected to a water absorbent treatment.
The water absorbent treatment enables the treated woven or knitted
fabric to exhibit an increased air permeability even upon wetting
with a small amount of sweat. There is no specific limitation to
the type of the water absorbent treatment. The following procedure
is exemplified as a preferred water absorbent treatment: a water
absorbent treatment agent, for example, a poly(ethylene glycol
diacrylate) or its derivative, or a poly(ethylene
terephthalate)-poly(ethylene glycol) copolymer is applied to the
woven or knitted fabric, in an amount of 0.25 to 0.50 wt. % based
on the weight of the woven or knitted fabric. Examples of the water
absorbent treatment method include a bath treatment method in which
a water absorbent treatment agent is added to a dyeing solution
during dyeing, and a coating method in which, for example, a woven
or knitted fabric is dipped prior to dry heat final set in a water
absorbent treatment solution, and squeezed with a mangle, a gravure
coating method and a screen printing method.
[0122] The clothes of the present invention are prepared from the
above woven or knitted fabric having no dimensional change upon
wetting with water and the above-mentioned woven or knitted fabric
the dimensions of which are reversibly enlarged upon wetting with
water, by a conventional process. The woven or knitted fabrics of
the present invention may be subjected to various treatments, for
example, dyeing, water absorbent treatment, conventional raising,
UV-ray shielding treatment or function-imparting treatment with,
for example, antibacterial agents, deodorants, moth-proofing
agents, luminous agents, retroreflective agents, negative-ion
generating agents and water repellants.
[0123] When a wearer puts the clothes of present invention on, and
sweats, portions of the clothes the dimensions of which are
reversibly enlarged upon wetting with water are enlarged, and the
portions flutter during wearer's movement to produce a ventilation
effect (bellows effect) to cause the wearer to be released from a
stuffy feeling and the stickiness created by the sweating.
Excellent wearable comfortability can thus be obtained. The
performance of the clothes of the present invention will be further
explained in Example 4 and Comparative Example 3 to be explained
later by making reference to FIG. 8.
[0124] The clothes of the present invention can be appropriately
used as outerwear, sportswear, underwear, etc. In addition,
accessories such as buttons may be safely attached to the clothes
of the invention.
EXAMPLES
[0125] The woven or knitted fabric and clothes of the present
invention will be further explained by with reference to the
following examples.
[0126] In examples and comparative examples, the following tests
were conducted.
<Intrinsic Viscosity of Polyester>
[0127] o-Chlorophenol was used as a solvent, and measurements were
made at 35.degree. C.
<Intrinsic Viscosity of Polyamide>
[0128] m-Cresol was used as a solvent, and measurements were
carried out at a temperature of 30.degree. C.
<Tensile Strength and Elongation at Break>
[0129] A filament sample was left to stand in a thermohygrostat
chamber at an atmospheric temperature of 25.degree. C. at a
humidity of 60% RH for one day and night. The sample was then set
in a Tensilon.TM. tensile tester (manufactured by Shimadzu
Corporation) with a sample length of 100 mm, and stretched at a
rate of 200 mm/min, and the tensile strength (cN/dtex) and the
elongation (%) at break were determined. In addition, n was 5 and
the average values were obtained.
<Shrinkage in Boiling Water>
[0130] The shrinkage in boiling water (hot water shrinkage) (%) was
determined by the method specified in JIS L 1013-1998 17-15. In
addition, n was 3, and the average value was obtained.
<Percentage of Crimp of Composite Filaments>
[0131] Using a rewinding frame having a frame peripheral length of
1.125 m, a composite yarn was rewound at a constant speed while a
load of 49/50 mN.times.9.times.total tex (0.1 gf.times.total
denier) was applied to the yarn, to form a small hank having wound
10 times. The small hank was twisted to form a double ring, and the
twisted hank was treated in boiling water for 30 minutes while an
initial load of 49/2,500 mN.times.20.times.9.times.total tex (2
mg.times.20.times.total denier) was applied. The hank treated in
boiling water was dried with a drier at a temperature of
100.degree. C. for 30 minutes, and then further treated with a dry
heat at 160.degree. C. for 5 minutes while the initial load was
applied thereto. After dry heat treatment was completed, the
initial load was removed, and the hank was left to stand in an
environment at 20.degree. C. and 65% RH for 24 hours. The initial
load and a heavy load of 98/50 mN.times.20.times.9.times.total tex
(0.2 gf.times.20.times.total denier) were then applied to the hank,
and the length L0 of the hank was measured. The heavy load alone
was immediately removed, and 1 minute after the load removal, the
length L1 of the hank was measured. Moreover, the hank was immersed
in warm water at a temperature of 30.degree. C. for 2 hours while
the initial load was applied thereto. The hank was then taken out,
and within 60 sec after taking out the hank, the hank was lightly
wiped with a filter paper sheet, while applying a pressure of 0.69
mN/cm.sup.2 (70 mgf/cm.sup.2) to the hank with a filter paper
sheet, 30 cm.times.30 cm. The initial load and the heavy load were
then applied, and the length L0' of the hank was measured. The
heavy load alone was then immediately removed, and 1 minute after
removal of the load the length L1' of the hank was measured. The
percentage of crimp DC (%) of the filament sample upon drying, the
percentage of crimp HC (%) of the sample upon wetting with water
and the difference (DC-HC) (%) between the percentage of crimp upon
drying and that upon wetting with water were calculated from the
data of the above mentioned measurements in accordance with the
following equations.
Percentage of crimp DC (%) upon drying=((L0-L1)/L0).times.100
Percentage of crimp HC (%) upon wetting with
water=((L0''L1').times.100
Percentage of crimp HC (%) upon wetting with
water=((L0'-L1')/L0').times.100
[0132] In addition, n is 5, and the average values are
obtained.
<Percentage of Crimp of Composite Filaments in Woven or Knitted
Fabric>
[0133] A woven or knitted fabric was left to stand in an air
atmosphere at a temperature of 20.degree. C. at a humidity of 65%
RH for 24 hours. Small samples each having dimensions of 30
cm.times.30 cm were taken (n=5) from the woven or knitted fabric in
the same direction thereof. A composite filament was taken out from
each small sample. A load of 1.76 mN/dtex (200 mg de) was applied
to the composite filament, and the length L2 of the filament was
measured. One minute after removal of the load, a load of 0.0176
mN/dtex (2 mg/de) was applied to the filament, and the length L3 of
the filament was measured. Moreover, the filament was immersed in
water at a temperature of 30.degree. C. for 2 hours, and then taken
out. Within 60 sec after taking out, the sample was held between
filter paper sheets, each in dimensions of 30 cm.times.30 cm, and a
pressure of 0.69 mN/cm.sup.2 (70 mgf/cm.sup.2) was applied thereto
for 5 sec to lightly wipe out water. A load of 1.76 mN/dtex (200 mg
de) was applied to the sample, and the length L2' of the filament
was measured. One minute after removal of the load, a load of
0.0176 mN/dtex (2 mg/de) was applied to the sample, and the length
L3' of the filament was measured. The percentage of crimp DC.sub.F
(%) upon drying, the percentage of crimp HC.sub.F (%) upon being
wetted with water and the difference (DC.sub.F-HC.sub.F) (%)
between the percentage of crimp upon drying and that upon being
wetted with water were calculated from the data measured as
mentioned above in accordance with the following equations. In
addition, n was 5, and the average values were obtained.
Percentage of crimp DC.sub.F (%) upon
drying=((L0f-L1f)/L1f).times.100
Percentage of crimp HC.sub.F (%) upon wetting with
water=((L0f'-L1f')/L1f').times.100
<Air Permeability>
[0134] The air permeability (ml/cm.sup.2/sec) of a fabric sample
upon drying and the air permeability (ml/cm.sup.2/sec) upon being
wetted with water were measured in accordance with JIS L 1096-1998
6.27.1, Method A (Fragile-type testing machine method). The term
"upon drying" designated the state of a sample left to stand in an
environment at a temperature of 20.degree. C. at a humidity of 65%
RH for 24 hours. On the other hand, the term "upon being wetted
with water" designated the state of a sample that was subjected to
the following procedures: the sample was immersed in water at a
temperature of 30.degree. C. for 2 hours, pulled up from the water,
and within 60 sec after pulling up the sample, held between a pair
of filter paper sheets each having dimensions of 50 cm.times.50 cm,
while a pressure of 490 N/m.sup.2 (50 kgf/m.sup.2) was being
applied to the sample for 1 minute to remove the water present
among the filaments. The air permeability is then determined (n=5),
and the average values are obtained. The change in air permeability
is calculated from the following equation:
[0135] Change (%) of air permeability=((air permeability upon
wetting with water)-(air permeability upon drying))/(air
permeability upon drying).times.100
<Stretch Percentage of Woven or Knitted Fabric>
[0136] The stretch elongation (%) in the warp direction and that in
the weft direction of a woven or knitted fabric were determined by
the same method as JIS L1096 8.14.1, Method B (Constant Load
Method) except that the load was changed to 1/10 (1.47 N=0.15
kgf).
[0137] The average of the measured data (n=5) was calculated.
<Measurement of Length of Yarn>
[0138] First, a woven or knitted fabric is left to stand in an air
atmosphere at 20.degree. C. and 65% RH for 24 hours. Small samples
(n=5) each having dimensions of 30 cm.times.30 cm are taken from
the woven or knitted fabric. One composite filaments yarn and
another filaments yarn were taken out from each sample. A yarn
length A (mm) of the composite filaments yarn and a yarn length B
(mm) of the different filaments yarn were measured. In the
measurement, a load of 1.76 mN/dtex (200 mg/de) was applied to a
sample yarn when the yarn is a non-elastic yarn, and a load of
0.0088 mN/dtex (1 mg/de) was applied to a sample yarn when the yarn
is an elastic one. In addition, n was 5, and the average was
calculated.
<Water Repellency>
[0139] The water repellency of the woven or knitted fabric was
determined in accordance with JIS L1092, 6.2 Spray Test.
<Change in Dimensions>
[0140] A woven or knitted fabric is allowed to stand in an
environment at a temperature of 20.degree. C. at a humidity of 65%
RH for 24 hours, and square samples (20 cm (warp).times.20 cm
(weft) were taken in the same direction as the woven or knitted
fabric. The area (cm.sup.2) of each sample is defined as an area
(cm.sup.2) upon drying. The sample was immersed in water at a
temperature of 20.degree. C. for 5 minutes (hereinafter referred to
as upon being wetted with water), then held between a pair of
filter paper sheets while applying a pressure of 490 N/m.sup.2 (50
kgf/m.sup.2) to the sample for 1 minute to remove water present
among filaments. The area of the sample was determined and defined
as an area of the sample (cm.sup.2) upon being wetted with water. A
change (%) in dimensions was calculated from the following equation
defining the change in area of the sample.
Change in area (%)=((area upon wetting with water)-(area upon
drying))/(area upon drying).times.100
Example 1
[0141] A nylon 6 having an intrinsic viscosity [.eta.] of 1.3 was
melted at 270.degree. C., and a modified poly(ethylene
terephthalate) in which 2.6 mol % of 5-sodium sulfoisophthalic acid
was copolymerized and that had an intrinsic viscosity [.eta.] of
0.39 was melted at 290.degree. C. Both molten polymers were
extruded through a spinneret for side-by-side type composite
filaments in an extrusion rate of 12.7 g/min for each polymer. The
spinneret was one described in Japanese Unexamined Patent
Publication (Kokai) No. 2000-144518. The spinning nozzle was formed
from two arc-shaped slits A and B arranged substantially on one the
same circumference at a spacing d. The area SA of the arc-shaped
slit A, the slit width A1, the area SB of the arc-shaped slit B,
the slit width B1 and the area SC surrounded by the inner
peripheral faces of the arc-shaped slits A and B simultaneously
satisfy the following requirements (1) to (4):
[0142] (1) B1<A1
[0143] (2) 1.1.ltoreq.SA/SB.ltoreq.1.8
[0144] (3) 0.4.ltoreq.(SA+SB)/SC.ltoreq.10.0
[0145] (4) d/A1.ltoreq.3.0
The poly(ethylene terephthalate) was extruded through the slit A
side, and the nylon 6 was extruded through the slit B side to form
a side-by-side type undrawn composite filaments yarn having a
cross-sectional profile as shown in FIG. 1. The undrawn filament
yarn was cooled to be solidified, and a spinning oil was imparted
thereto. The filament yarn was drawn and heat treated at a speed of
1,000 m/min, by preheating with a preheating roller at a
temperature of 60.degree. C., and drawing and heat treating between
the preheating roller and a heating roller having a speed of 3,050
m/min and heated at 150.degree. C. at a draw ratio of 3.05. The
resultant yarn was wound up. A composite filaments yarn of 84
dtex/24 fil was obtained.
[0146] The drawn composite filaments yarn thus obtained had a
tensile strength at break of 3.4 cN/dtex and an elongation at break
of 40%. Moreover, when the composite filaments yarn was subjected
to a treatment in boiling water to cause the filaments to crimp,
the filaments yarn had a percentage of crimp DC upon drying of 3.3%
and a percentage of crimp HC upon being wetted with water of 1.6%.
Thus the difference (DC-HC) between the percentage of crimp DC upon
drying and the percentage of crimp HC upon wetting with water was
1.7%.
[0147] Using a 28-gauge double tubular knitting machine, a tubular
knitted fabric having an interlock stitch with a knitting density
of 42 courses/2.54 cm and 35 wales/2.54 cm was prepared from
non-twisted composite filaments yarns (no treatment with boiling
water was applied and no crimp was manifested on the filaments)
alone.
[0148] The tubular knitted fabric was dyed at a temperature of
130.degree. C. for a peak temperature-keeping time of 15 minutes to
manifest the latent crimpability of the composite filaments yarn.
During dyeing, a water-absorbent agent (poly(ethylene
terephthalate)-poly(ethylene glycol) copolymer) was added to the
dyeing bath in an amount of 2 ml per liter of the dyeing solution.
The water-absorbent agent was imparted to the knitted fabric by the
bath treatment during dyeing. Then the tubular knitted fabric was
dry heat final set at 160.degree. C. for one minute.
[0149] The knitted fabric thus obtained had a basis weight of 214
g/m.sup.2, and had a stretch percentage of 70% in the warp
direction, and a stretch percentage of 110% in the weft direction,
an air permeability upon drying of 90 ml/cm.sup.2/sec, an air
permeability upon being wetted with water of 370 ml/cm.sup.2/sec
and a change in air permeability of 311%. The significant
improvement of the air permeability upon wetting with water was
confirmed with satisfactory. Moreover, composite filaments taken
from the knitted fabric had a percentage of crimp DC.sub.F upon
drying of 68% and a percentage of crimp HC.sub.F upon being wetted
with water of 22%. That is, the difference (DC.sub.F-HC.sub.F)
between the percentage of crimp upon drying and the one upon
wetting with water was 46%.
Example 2
[0150] The same composite filaments yarn as used in Example 1 and a
conventional poly(ethylene terephthalate) multifilaments yarn (84
dtex/30 f) were used. Using 28-gauge double tubular knitting
machine in the same manner as in Example 1, the composite filaments
yarns and the poly(ethylene terephthalate) multifilaments yarns
were alternately fed to the machine with every one yarn to form a
tubular knitted fabric having an interlock stitch with a knitting
density of 54 courses/2.54 cm and 34 wales/2.54 cm. The tubular
knitted fabric was subjected to dyeing, water absorbent treatment
and dry heat final set in the same manner as in Example 1.
[0151] The knitted fabric thus obtained had a basis weight of 206
g/m.sup.2, and exhibited a stretch percentage of 50% in the warp
direction, a stretch percentage of 100% in the weft direction, an
air permeability upon drying of 150 ml/cm.sup.2/sec, an air
permeability upon being wetted with water of 280 ml/cm.sup.2/sec
and a change in air permeability of 87%. The knitted fabric was
satisfactory because the air permeability upon being wetted with
water was greatly improved. Moreover, a composite filaments taken
from the knitted fabric had a percentage of crimp DC.sub.F upon
drying of 63% and a percentage of crimp HC.sub.F upon wetting with
water of 20%. That is, the difference (DC.sub.F-HC.sub.F) between
the percentage of crimp upon drying and that upon being wetted with
water was 43%.
Comparative Example 1
[0152] A nylon 6 having an intrinsic viscosity [.eta.] of 1.3 and a
modified poly(ethylene terephthalate) in which 2.6 mol % of
5-sodium sulfoisophthalic acid was copolymerized and that had an
intrinsic viscosity of 0.48 were melted at 270.degree. C. and
290.degree. C., respectively, extruded through a spinneret for
forming a side-by-side type composite filaments (explained in
Example 1) in an extrusion rate of 12.7 g/min for each polymer to
form a side-by-side type composite filaments having a
cross-sectional profile as shown in FIG. 1. The extruded filaments
were cooled to solidify them, and a spinning oil was imparted
thereto. The undrawn filament yarn thus obtained was drawn and
heat-treated at a speed of 1,000 m/min, by preheating by a
preheating roller at a temperature of 60.degree. C., and drawing
and heat treating between the preheating roller and a heating
roller at a speed of 2,700 m/min at a temperature of 150.degree. C.
The resultant filament yarn was wound. A composite filament yarn of
84 dtex/24 fil. was obtained. The drawn composite filaments yarn
thus obtained had a tensile strength at break of 2.3 cN/dtex and an
elongation at break of 41%. The composite filaments yarn was
subjected to a treatment in boiling water and the percentage of
crimp of the resultant filaments was measured. The percentage of
crimp DC upon drying was 1.2% and a percentage of crimp HC upon
being wetted with water was 3.9%. Thus the difference (DC-HC)
between the percentage of crimp DC upon drying and the percentage
of crimp HC upon being wetted with water was -2.7%.
[0153] From the composite filaments yarns, a tubular knitted fabric
was prepared in the same manner as in Example 1. The resultant
tubular knitted fabric was subjected to dyeing, water absorbent
treatment and dry final set in the same manner as in Example 1.
[0154] The knitted fabric thus obtained had a basis weight of 170
g/m.sup.2, and exhibited a stretch percentage of 52% in the warp
direction, a stretch percentage of 102% in the weft direction, an
air permeability upon drying of 230 ml/cm.sup.2/sec, an air
permeability upon being wetted with water of 160 ml/cm.sup.2/sec
and a change in air permeability of -30%. The knitted fabric was
unsatisfactory because the air permeability upon being wetted with
water was low. Moreover, a composite filament taken from the
knitted fabric had a percentage of crimp DC.sub.F upon drying of
54% and a percentage of crimp HC.sub.F upon being wetted with water
of 65%. That is, the difference (DC.sub.F-HC.sub.F) between the
percentage of crimp upon drying and that upon being wetted with
water was -11%.
Example 3
[0155] The same side-by-side type composite filaments yarns as in
Example 1 were produced. The composite filaments yarns were
supplied to a conventional 28-gauge tricot knitting machine. The
composite filaments yarns were fed to a back guide bar of the
knitting machine at a full set. On the other hand, a conventional
false twisted, crimped poly(ethylene terephthalate) multifilament
yarns (33 dtex/36 fil.) having a percentage of crimp of 20% were
simultaneously fed to a front guide bar of the tubular knitting
machine at a full set to give a knitted fabric having a half tricot
stitch (back: 10-12, front: 23-10) with an on-machine density of 80
courses/2.54 cm.
[0156] The knitted fabric was dyed at 130.degree. C. for a peak
temperature-keeping time of 15 minutes so that the latent
crimpability of the composite filaments was manifested. The knitted
fabric was then subjected to padding treatment with a fluororesin
water repellent treatment liquid. The treated knitted fabric was
then dried at a temperature of 100.degree. C., and dry heat final
set at a temperature of 160.degree. C. for 1 minute.
[0157] The knitted fabric thus obtained had a basis weight of 220
g/m.sup.2, and had a stretch percentage of 13% in the warp
direction, a stretch percentage of 30% in the weft direction, a
water repellency of 5 points, an air permeability upon drying of 45
ml/cm.sup.2/sec, an air permeability upon being wetted with water
of 64 ml/cm.sup.2/sec and a change in air permeability of 42%. The
knitted fabric was satisfactory because the air permeability upon
wetting with water was greatly enhanced. Moreover, composite
filaments taken from the knitted fabric exhibited a percentage of
crimp DC.sub.F upon drying of 64% and a percentage of crimp
HC.sub.F upon being wetted with water of 32%. That is, the
difference (DC.sub.F-HC.sub.F) between the percentage of crimp upon
drying and that upon being wetted with water was 32%.
Comparative Example 2
[0158] A side-by-side type composite filaments yarns were produced
from a nylon 6 and a 5-sodium sulfoisophthalic acid-copolymerized
poly(ethylene terephthalate) resin in the same manner as in
Comparative Example 1.
[0159] Using the composite filaments yarns, a knitted fabric was
prepared in the same manner as in Example 3. The knitted fabric was
subjected to dyeing, water repellency treatment and dry final
set.
[0160] The knitted fabric thus obtained had a basis weight of 210
g/m.sup.2, and exhibited a stretch percentage of 12% in the warp
direction, a stretch percentage of 22% in the weft direction, a
water repellency of 5 points, an air permeability upon drying of 54
ml/cm.sup.2/sec, an air permeability upon being wetted with water
of 41 ml/cm.sup.2/sec and a change in air permeability of -24%. The
knitted fabric was unsatisfactory because the air permeability upon
being wetted with water was low. Moreover, composite filaments
taken from the knitted fabric exhibited a percentage of crimp
DC.sub.F upon drying of 56% and a percentage of crimp HC.sub.F upon
being wetted with water of 62%. That is, the difference
(DC.sub.F-HC.sub.F) between the percentage of crimp upon drying and
that upon being wetted with water was -6% which was
unsatisfactory
Example 4
[0161] A nylon 6 having an intrinsic viscosity [.eta.] of 1.3 and a
modified poly(ethylene terephthalate) in which 2.6 mol % of
5-sodium sulfoisophthalic acid was copolymerized and that had an
intrinsic viscosity of 0.39 were melted at 270.degree. C. and
290.degree. C., respectively, extruded through the same composite
spinning spinneret as in Example 1, at an extrusion rate of 12.7
g/min for each polymer, to form a side-by-side type composite
filaments yarn. The extruded yarn was cooled to be solidified, and
a spinning oil was imparted thereto. The yarn was then drawn and
heat-treated at a speed of 1,000 m/min, by preheating by a
preheating roller at a temperature of 60.degree. C., and drawn and
heat treated between the preheating roller and a heating roller
having a speed of 3,050 m/min a temperature of at 150.degree. C.
The resultant yarn was wound. A composite filament yarn of 84
dtex/24 fil was obtained. The drawn composite filament yarn thus
obtained had a tensile strength of 3.4 cN/dtex and an elongation at
break of 40%. When the composite filaments yarn was subjected to a
treatment in boiling water and the percentage of crimp was
measured, it was found that the percentage of crimp DC upon drying
was 3.3% and the percentage of crimp HC upon being wetted with
water was 1.6%. The difference (DC-HC) between the percentage of
crimp upon drying DC and the percentage of crimp upon being wetted
with water HC was therefore 1.7%.
[0162] The composite filaments yarn (that was not subjected to
treatment in boiling water, and that had no crimps, and
non-twisted) alone was used, to produce a tubular knitted fabric
having a plain knitting stitch and a density of 65 courses/2.54 cm
and 37 wales/2.54 cm, by using a 28-gauge double tubular knitting
machine.
[0163] The tubular knitted fabric was dyed at 130.degree. C. for a
peak temperature-keeping time of 15 minutes to manifest the latent
crimpability of the composite filaments yarn. The tubular knitted
fabric was then subjected to dry heat final set at a temperature of
160.degree. C. for 1 minute.
[0164] The knitted fabric thus obtained (knitted fabric having
dimensions that were reversibly increased upon wetting with water)
had a basis weight of 120 g/m.sup.2, a knitting density of 71
courses/2.54 cm and 61 wales/2.54 cm, and exhibited a dimensional
change of 21% (7% in the warp direction and 13% in the weft
direction).
[0165] Separately, using a 28-gauge double knitting machine, a
tubular knitted fabric having an interlock stitch with a gray
fabric density of 45 courses/2.54 cm and 41 wales/2.54 cm was
prepared from a false twisted and crimped poly(ethylene
terephthalate) yarn (56 dtex/72 fil.). The knitted fabric was
similarly dried as above. The knitted fabric (that had no
dimensional change caused by wetting with water) was then cut and
sewn to give a shirt with a half-sleeve length.
[0166] Next, the breast (15 cm long and 20 cm wide) alone of the
shirt was cut and removed, and a cut piece of the composite
filaments yarn knitted fabric was sewn and fixed to the breast of
the shirt as shown in FIG. 6.
[0167] A panelist wore the shirt thus obtained, and a wearing test
was conducted in a room adjusted to a temperature of 28.degree. C.
and a humidity of 50% RH according to the wearing step mentioned
below, and the humidity within the clothes (space between the skin
and the clothes) was determined. The results are shown by a curve A
in FIG. 8. During physical exercise, the panelist hardly felt
stuffy due to the ventilation effect of the piece of the composite
filament knitted fabric arranged in the breast of the shirt. After
the physical exercise, the panelist felt significantly less stuffy,
and felt comfortable due to the ventilation effect in combination
with the wind.
Wearing Test:
[0168] rest for 5 minutes (with wind at 1.5 m/sec).fwdarw.running
for 15 minutes (10 km/h).fwdarw.rest for 10 minutes (without
wind).fwdarw.rest for 20 minutes (with wind at 1.5 m/sec)
Comparative Example 3
[0169] A panelist wore the same shirt prepared from the false
twisted and crimped poly(ethylene terephthalate) yarn (56 dtex/72
f) alone as in Example 1, and the same wearing test as in Example 4
was conducted. The results are shown by a curve B in FIG. 8. The
panelist who wore the shirt felt significantly stuffy during
physical exercise because the shirt had substantial no ventilation
effect. Moreover, the stuffy feeling lasted for a long time after
the physical exercise was finished, and the panelist felt
uncomfortable.
INDUSTRIAL APPLICABILITY
[0170] The woven or knitted fabric of the present invention
containing crimped composite filaments and clothes of the present
invention containing the woven or knitted fabric exhibit an air
permeability that is increased upon wetting with water to promote
drying of the woven or knitted fabric. Drying of the woven or
knitted fabric causes the air permeability to decrease and to
improve the warmth retention. The woven or knitted fabric is
therefore useful for outerwear, sportswear, underwear and other
clothes.
* * * * *