U.S. patent application number 10/425803 was filed with the patent office on 2003-11-13 for cooling garment made of water-resistant fabric.
Invention is credited to Hill, Dorothy M., Lazar, Robert P..
Application Number | 20030208831 10/425803 |
Document ID | / |
Family ID | 29406952 |
Filed Date | 2003-11-13 |
United States Patent
Application |
20030208831 |
Kind Code |
A1 |
Lazar, Robert P. ; et
al. |
November 13, 2003 |
Cooling garment made of water-resistant fabric
Abstract
A cooling garment constructed, at least in part, of a cooling
fabric. The cooling fabric includes an upper layer that includes a
water-resistant fabric, a lower layer that includes a
water-resistant fabric, a plurality of chambers disposed between
the upper layer and the lower layer formed by stitching the upper
layer and the lower layer together using a water wickable thread,
and a superabsorbent polymer contained within a majority of the
chambers.
Inventors: |
Lazar, Robert P.;
(Pittsburgh, PA) ; Hill, Dorothy M.; (Pittsburgh,
PA) |
Correspondence
Address: |
Kent E. Baldauf, Jr.
Webb Ziesenheim Logsdon Orkin & Hanson
700 Koppers Building
436 Seventh Avenue
Pittsburgh
PA
15219-1818
US
|
Family ID: |
29406952 |
Appl. No.: |
10/425803 |
Filed: |
April 29, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60380165 |
May 7, 2002 |
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Current U.S.
Class: |
2/69 |
Current CPC
Class: |
A41D 20/005 20130101;
A41D 31/085 20190201; A41D 13/0053 20130101 |
Class at
Publication: |
2/69 |
International
Class: |
A41B 001/00 |
Claims
We claim:
1. A cooling fabric comprising: an upper layer comprising a
water-resistant fabric; a lower layer comprising a water-resistant
fabric; a plurality of chambers disposed between the upper layer
and the lower layer formed by stitching the upper layer and the
lower layer together using a water wickable thread; and a
superabsorbent polymer contained within a majority of the
chambers.
2. The cooling fabric of claim 1, wherein the water-resistant
fabric of the upper layer and the lower layer are independently
comprised of fabrics containing fibers comprised of materials
selected from the group consisting of polyamides, polyesters,
polyurethanes, vinyl, acrylic, fluoropolymers, aramid,
poly(p-phenylene-2,6-benzobisthiazole), and
poly(p-phenylene-2,6-benzobisoxazole).
3. The cooling fabric of claim 1, wherein one or both of the fabric
of the upper layer and the fabric of the lower layer is a fabric
comprising a substrate fabric and a water-resistant coating layer
formed from a water-resistant coating composition over at least a
portion of a surface of the substrate fabric.
4. The cooling fabric of claim 3, wherein the substrate fabric is
comprised of fabrics containing fibers comprised of materials
selected from the group consisting of cotton, wool, polyamides,
polyesters, polyurethanes, vinyl, acrylic, fluoropolymers, aramid,
poly(p-phenylene-2,6-benzobisthiazole), and
poly(p-phenylene-2,6-benzobis- oxazole).
5. The cooling fabric of claim 3, wherein the water-resistant
coating composition comprises one or more materials selcted from
the group consisting of natural rubber, synthetic rubber, silicone
rubber, fluoropolymers, polyurethanes, and acrylics.
6. The cooling fabric of claim 1, wherein the chambers are
dimensioned to form a shape of from 1 to 60 mm.sup.2 in area in the
upper layer and the lower layer.
7. The cooling fabric of claim 1, wherein the water wickable thread
includes one or more materials selected from the group consisting
of cotton, wool, hemp, copolyetheresters, polyesters, and
polyehters.
8. The cooling fabric of claim 1, wherein the superabsorbent
polymer is selected from the group consisting of natural gums,
cellulosics, synthetic hydrogel polymers, and mixtures thereof.
9. The cooling fabric of claim 8, wherein the natural gums are
selected from xanthan, guar, agar, pectin, gum arabic, locust bean
gum, hydroxypropyl guar gum, polyglucomannan gum, cationic guar
gum, anionic guar gum, alginate, irish moss, and gum arabic.
10. The cooling fabric of claim 8, wherein the cellulosics are
selected from methyl cellulose, ethyl cellulose, carboxymethyl
cellulose, carboxyethyl cellulose, hydroxyethyl cellulose,
hydroxymethyl cellulose, and hydroxypropylcellulose.
11. The cooling fabric of claim 8, wherein the synthetic hydrogel
polymers comprise crosslinked, water-swellable acrylic
copolymers.
12. The cooling fabric of claim 8, wherein the synthetic hydrogel
polymers comprise repeat units from one or more monomers selected
from the group consisting of (meth)acrylic acid, maleic acid,
2-(meth)acrylamido-2-methy- l propane sulfonic acid, styrene
sulfonate, vinyl sulfonic acid, and their corresponding ammonia,
amine and alkali metal salts, (meth)acrylamide, vinyl alcohol,
vinyl acetate, maleic anhydride, alkyl vinyl ethers,
vinylmorpholinone, vinylpyrridine, vinyl pyrrolidone, and
acrylonitrile; and one or more crosslinkers selected from the group
consisting of N,N'-methylenebis(meth)acrylamide, (poly)ethylene
glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate,
trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate,
glycerol acrylate methacrylate, ethylene-oxide-modified
trimethylolpropane tri(meth)acrylate, pentaerythritol
tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, triallyl
cyanurate, triallyl isocyanurate, triallyl phosphate,
triallylamine, poly(meth)allyloxyalkanes, (poly)ethylene glycol
diglycidyl ether, glycerol diglycidyl ether, ethylene glycol,
polyethylene glycol, propylene glycol, glycerol, pentaerythritol,
ethylenediamine, ethylene carbonate, propylene carbonate,
polyethylenimine, glycidyl (meth)acrylate, diallyl sucrose,
triallyl sucrose triallyl amine, and triallyl methyl ammonium
chloride.
13. The cooling fabric of claim 1, wherein the superabsorbent
polymer has an unhydrated particle size of from 20 to 1,000
microns.
14. The cooling fabric of claim 1, fashioned in the form of a
garment selected from the group consisting of a blanket, a cape, a
vest, a scarf, a neckerchief, a cap, a hat, a headband, and a do
rag.
15. A cooling garment comprising a cooling fabric comprised of: an
upper layer comprising a water-resistant fabric comprising a
substrate fabric and a water-resistant coating layer formed from a
water-resistant coating composition over at least a portion of a
surface of the substrate fabric; a lower layer comprising a
water-resistant fabric comprising a substrate fabric and a
water-resistant coating layer formed from a water-resistant coating
composition over at least a portion of a surface of the substrate
fabric; a plurality of chambers disposed between the upper layer
and the lower layer formed by stitching the upper layer and the
lower layer together using a water wickable thread wherein the
chambers are dimensioned to form a shape of from 1 to 60 mm.sup.2
in area in the upper layer and the lower layer; and a
superabsorbent polymer selected from the group consisting of
natural gums, cellulosics, synthetic hydrogel polymers, and
mixtures thereof, contained within the chambers.
16. The cooling garment of claim 15, wherein the substrate fabric
is comprised of fabrics containing fibers comprised of materials
selected from the group consisting of cotton, wool, polyamides,
polyesters, polyurethanes, vinyl, acrylic, fluoropolymers, aramid,
poly(p-phenylene-2,6-benzobisthiazole), and
poly(p-phenylene-2,6-benzobis- oxazole).
17. The cooling garment of claim 15, wherein the water-resistant
coating composition comprises one or more materials selected from
the group consisting of natural rubber, synthetic rubber, silicone
rubber, fluoropolymers, polyurethanes, and acrylics.
18. The cooling garment of claim 15, wherein the water wickable
thread includes one or more materials selected from the group
consisting of cotton, wool, hemp, copolyetheresters, polyesters,
and polyethers.
19. The cooling garment of claim 15, wherein the natural gums are
selected from xanthan, guar, agar, pectin, gum arabic, locust bean
gum, hydroxypropyl guar gum, polyglucomannan gum, cationic guar
gum, anionic guar gum, alginate, irish moss, and gum arabic.
20. The cooling garment of claim 15, wherein the cellulosics are
selected from methyl cellulose, ethyl cellulose, carboxymethyl
cellulose, carboxy ethyl cellulose, hydroxyethyl cellulose,
hydroxymethyl cellulose, and hydroxypropylcellulose.
21. The cooling garment of claim 15, wherein the synthetic hydrogel
polymers comprise crosslinked, water-swellable acrylic
copolymers.
22. The cooling garment of claim 15, wherein the synthetic hydrogel
polymers comprise repeat units from one or more monomers selected
from the group consisting of (meth)acrylic acid, maleic acid,
2-(meth)acrylamido-2-methyl propane sulfonic acid, styrene
sulfonate, vinyl sulfonic acid, and their corresponding ammonia,
amine and alkali metal salts, (meth)acrylamide, vinyl alcohol,
vinyl acetate, maleic anhydride, alkyl vinyl ethers,
vinylmorpholinone, vinylpyrridine, vinyl pyrrolidone, and
acrylonitrile; and one or more crosslinkers selected from the group
consisting of N,N'-methylenebis(meth)acrylamide, (poly)ethylene
glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate,
trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate,
glycerol acrylate methacrylate, ethylene-oxide-modified
trimethylolpropane tri(meth)acrylate, pentaerythritol
tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, triallyl
cyanurate, triallyl isocyanurate, triallyl phosphate,
triallylamine, poly(meth)allyloxyalkanes, (poly)ethylene glycol
diglycidyl ether, glycerol diglycidyl ether, ethylene glycol,
polyethylene glycol, propylene glycol, glycerol, pentaerythritol,
ethylenediamine, ethylene carbonate, propylene carbonate,
polyethylenimine, glycidyl (meth)acrylate, diallyl sucrose,
triallyl sucrose triallyl amine, and triallyl methyl ammonium
chloride.
23. The cooling garment of claim 15, wherein the superabsorbent
polymer has an unhydrated particle size of from 20 to 1,000
microns.
24. The cooling garment of claim 15, wherein the garment is a type
selected from the group consisting of a blanket, a cape, a vest, a
scarf, a neckerchief, a cap, a hat, a headband, and a do rag.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application Serial No. 60/380,165, filed May 7, 2002, entitled
"Thermal Control Device Using Fabric and Synthetic Anionic Acrylic
Copolymer," the disclosure of which is hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to garments that are
particularly useful for cooling or enhancing heat flow out of and
away from humans or animals.
[0004] 2. Description of Related Art
[0005] During physical activity, such as strenuous exercise or
manual labor, the body generates heat. In humans, the body acts to
cool itself and maintain a constant temperature through
perspiration, which cools the skin surfaces of the body through
evaporation. Many animals, on the other hand, cool themselves
through panting, and the associated evaporative cooling of
saliva.
[0006] When atmospheric temperatures are high, i.e., greater than
about 30.degree. C. (86.degree. F.), and particularly when the
relative humidity is also high (typically greater than 50%), the
aforementioned natural cooling methods are insufficient, and the
body temperature rises above a normal temperature. In such cases,
the human or animal is at risk of developing various ailments such
as heat stroke and in severe cases heart failure and death.
[0007] In order to aid body cooling in such situations, various
cooling garments have been devised to draw heat from the body
and/or to promote lowering the body temperature. U.S. Pat. No.
6,473,910 to Creagan et al., for example, discloses a cooling
garment that has an inner layer of a thermoplastic polymer material
that is liquid impermeable and vapor permeable, an outer liquid
permeable layer, and a central absorbent layer that contains a
stabilized matrix of cellulosic fibers and thermoplastic polymer
fibers. The cooling garment is saturated with water or other
liquids to provide the wearer relief from the heat by evaporative
cooling through the outer liquid permeable layer.
[0008] U.S. Pat. Nos. 6,464,672 and 5,722,482 to Buckley disclose a
multilayer composite material and method for evaporative cooling of
a person. The material employs an evaporative cooling liquid that
changes phase from a liquid to a gaseous state to absorb thermal
energy. The evaporative cooling liquid is absorbed into a
superabsorbent material enclosed within the multilayer composite
material. The composite is made of a perforated barrier material
around the outside to regulate the evaporation rate of the phase
change liquid. The multilayer composite material may be fashioned
into blankets, garments and other articles.
[0009] U.S. Pat. No. 6,185,744 to Poholski discloses a thermal
garment that includes a shell and a thermal insert that overlay and
cover a substantial portion of the back and the chest of a user.
The shell has inner and outer layers that are interconnected to
define a chamber between the layers. A thermal insert is placed in
the chamber. The thermal insert has two congruent layers and
multiple compartments defined between the two layers, with one of
the compartments being sealed and containing a thermal storage
medium. The thermal storage medium is a layer of insulating
material such as Thinsulate brand insulation (3M, St. Paul, Minn.)
or other suitable, garment-quality insulation.
[0010] U.S. Pat. No. 6,017,606 to Sage et al. discloses a reusable
thermal pack that includes a bag formed of a water-permeable fabric
having a plurality of laterally adjacent compartments, and a
superabsorbent polymer disposed in the bag compartments. The
polymer forms a gel in the presence of an aqueous solution, and the
bag compartments are gel-retainable. The thermal pack, once
hydrated, becomes cool and stays cool for several days without
refrigeration.
[0011] U.S. Pat. No. 5,787,505 to Piwko et al. discloses a shirt
having one or more pouches to receive a cooling pack. The cooling
pack is cooled before use, and includes sealed compartments
containing water or other material which changes state by absorbing
heat to cool the wearer.
[0012] U.S. Pat. No. 5,755,110 to Silvas discloses a cooling vest
having a plurality of elongated pocket partitions formed on the
front and backside of the vest, which contain beads of
polyacrylamide material that absorb water to form a gel that may be
chilled or frozen to provide a cooling effect on the upper torso of
a wearer. The cooling effect is facilitated by the non-impervious
properties of cotton containing double layer fabric used in the
construction of the vest that permits evaporation.
[0013] U.S. Pat. No. 5,606,746 to Shelton et al. discloses a vest
having a polyacrylamide copolymer filler that cools the body by
activating the cooling stage, which is done by placing the vest in
water for a period of time. The vest is made of materials that can
be washed by the individual. They can be stored for days in plastic
bags in the refrigerator. If long-term storage is needed, the vest
is readily dried by line-drying and then put away until ready for
use again.
[0014] All of the above-described body cooling garments are
constructed of porous fabrics that in various ways include
compartments that contain a water-absorbing material. The
water-absorbing material is saturated with water prior to wear and
provides cooling through the evaporation of water through the
porous fabric.
[0015] The above-described garments have several shortcomings.
First, in many cases, moisture from the the water-absorbing
material may be transferred from the water-absorbing material
through the porous fabric to the clothing or skin of the wearer,
causing discomfort or damaging clothing. Second, the
water-absorbing material in the garment dries out, i.e., loses its
water and cooling capacity after a few days due to evaporation of
the water through the porous fabric. Finally, often the
water-absorbing material will settle to the lower portions of the
garment, leaving the primary heat transfer sites of the upper torso
unexposed or minimally exposed to the heat transfer properties of
the water-absorbing material.
[0016] There is a need to provide garments that provide thermal
cooling to humans and animals that maintain their moisture level
and cooling capacity for a week or more when left hanging at
ambient conditions, do not transfer moisture to the skin or
clothing of the wearer, and maintain the water-absorbing material
at locations adjacent to the primary heat transfer points in the
upper torso.
SUMMARY OF THE INVENTION
[0017] The present invention is directed to a cooling garment that
includes an upper layer that includes a water-resistant fabric, a
lower layer that includes a water-resistant fabric, a plurality of
chambers disposed between the upper layer and the lower layer
formed by stitching the upper layer and the lower layer together
using a water wickable thread, and a superabsorbent polymer
contained within a majority of the chambers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a plan view of a cooling fabric of the present
invention;
[0019] FIG. 2 shows a sectional view of the cooling fabric taken
along line A-A in FIG. 1;
[0020] FIG. 3 and FIG. 4 show a sectional view of the cooling
fabric taken along line B-B in FIG. 1;
[0021] FIG. 5 shows a perspective front view of a first vest
structure of the present invention;
[0022] FIG. 6A shows a front elevation view of a second vest
structure of the present invention;
[0023] FIG. 6B shows a front elevation view of a third vest
structure of the present invention;
[0024] FIG. 7 shows a perspective view of a cap structure of the
present invention;
[0025] FIG. 8 shows a perspective view of a person wearing a
headband structure of the present invention;
[0026] FIG. 9 shows a front elevation view of a hat structure of
the present invention; and
[0027] FIG. 10 shows a perspective front view of a fourth vest
structure of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0028] Unless otherwise indicated, all numbers or expressions
referring to quantities of ingredients, reaction conditions, etc.,
used herein are to be understood as modified in all instances by
the term "about."
[0029] Various numerical ranges are disclosed in this patent
application. Because these ranges are continuous, they include
every value between the minimum and maximum values. Unless
expressly indicated otherwise, the various numerical ranges
specified in this application are approximations.
[0030] As used herein and in the claims, the term "superabsorbent
polymer" refers to any suitable natural or synthetic polymeric
material in a dry form that is capable of absorbing and storing
many times its weight in water. After absorbing water, the
superabsorbent polymer takes on a particulate, jelly-like or
hydrogel form, but remains in a non-flowable state.
[0031] As used herein and in the claims, the term "water-resistant"
refers to materials that generally repel or resist penetration by
water through the material where the materials are not entirely
waterproof. In other words, water-resistant materials generally
hinder the penetration of water through their fabric and provide a
water-repellent barrier.
[0032] As used herein and in the claims, the term "water wickable
thread" refers to any suitable fiber that is capable of conveying
water and/or aqueous solutions by capillary action. In other words,
a water wickable thread useful in the present invention may
include, but is not limited to, any fiber, bundle of fibers, or
loosely twisted, braided, or woven cord, tape, or tube that by
capillary attraction draws water from one location to another.
[0033] As used herein and in the claims, the term "cooling garment"
refers to any suitable fabric, piece of fabric, article of
clothing, or other article that is capable of transfering heat from
the body of a human and/or an animal. Suitable articles that the
term cooling garment includes are, without limitation, blankets,
capes, vests, scarfs, neckerchiefs, caps, hats, headbands, do rags,
and other headware or other systems.
[0034] The present invention provides a cooling garment that
includes an upper layer that contains a water-resistant fabric, a
lower layer that contains a water-resistant fabric, a plurality of
chambers disposed between the upper layer and the lower layer
formed by stitching the upper layer and the lower layer together
using a water wickable thread, and a superabsorbent polymer
contained within a majority of the chambers.
[0035] The present cooling garment is made, at least in part, using
a cooling fabric as shown in FIGS. 1-4. The cooling fabric 10
includes a plurality of chambers 11, that are defined by an upper
layer 12, a lower layer 14 and edges defined by the stitched
pattern of a water wickable thread 18. Chamber 11 contains
superabsorbent polymer particles 16.
[0036] When used as a cooling garment or as part of a cooling
garment, superabsorbent polymer 16 in chamber 11 is exposed to and
adsorbs or is hydrated by water or an aqueous solution. Once the
superabsorbent polymer 16 has been hydrated, when cooling fabric 10
is placed against the skin of a human or animal, it actively acts
to draw heat or thermal energy from the skin, cooling the
wearer.
[0037] Although not being limited to any one theory, it is believed
that when cooling garments containing the above-described cooling
fabric are draped or worn or placed in proximity of a human or
animal body, the evaporative effects of the hydrated superabsorbent
polymer provide convective or conductive cooling.
[0038] Hydration of superabsorbent polymer 16 is accomplished by
placing or otherwise contacting cooling fabric 10 with water or an
aqueous solution. As FIG. 3 shows, water does not directly enter
chamber 11 through upper layer 12 or lower layer 14 because each
layer contains a water-resistant material. As indicated by the
arrows in FIG. 3, water or an aqueous solution is conveyed by water
wickable thread 18 to chamber 11. Once the water or aqueous
solution has entered chamber 11, it is absorbed by superabsorbent
polymer 16, which expands from its dry state as shown in FIG. 3 to
its enlarged hydrated state as shown in FIG. 4. Typically,
superabsorbent polymer 16 absorbs enough water or aqueous solution
to expand and fill the volume of chamber 11.
[0039] In an embodiment of the present invention, holes created by
sewing and stitching upper layer 12 to lower layer 14 provide a
pathway for water or aqueous solution to be conveyed into chamber
11. In this embodiment, thread 18 may or may not be of a water
wickable construction.
[0040] The cooling fabric can be used to make any suitable type of
cooling garment known in the art. Suitable cooling garments
include, but are not limited to, blankets, capes, vests, scarfs,
neckerchiefs, caps, hats, headbands, do rags, and other headware or
other systems.
[0041] In a non-limiting embodiment of the present invention, the
cooling garment may be a first vest as shown in FIG. 5. First vest
20 includes the above-described cooling fabric in the areas of
first vest 20 that contact the chest, neck, and upper back of the
wearer. The chambers 24 are defined by the stitching pattern of
water wickable thread 22. First vest 20 may be closed by fastening
buttons 26 through button holes 28. As shown in FIG. 5, the portion
of first vest 20 that would be in contact with the lower back and
waist area of the wearer does not include chambers 24 defined by a
stitching pattern of water wickable thread 22. This portion of
first vest 20 may be constructed of the present cooling fabric
without any superabsorbent polymer being present in chambers 24, or
alternatively, this portion of first vest 20 may be constructed of
another fabric, which may or may not be water-resistant. Examples
of non-water-resistant fabrics that may be used include, but are
not limited to, cotton, wool, nylon, rayon, acrylics, and fabric
blends as are well known in the art.
[0042] In another non-limiting embodiment of the present invention,
the cooling garment may be a second vest as shown in FIG. 6A.
Second vest 30 includes the above-described cooling fabric in the
areas of second vest 30 that contact the shoulders, upper back and
lower torso of the wearer. Chambers 34 extend laterally and are
defined by the stitching pattern of water wickable thread 32.
Second vest 30 may be closed by fastening a VELCRO.RTM. fastener 36
(Velcro Industries B. V., Curacao, AN). Further to this embodiment
as shown in FIG. 6B, which includes the features described in FIG.
6A above, the second vest 30 may include light reflective material
38 positioned so as to encircle the chest and waist areas when the
vest is worn.
[0043] In an additional non-limiting embodiment of the present
invention, the cooling garment is a cap as shown in FIG. 7. Cap 40
may be entirely constructed of the above-described cooling fabric.
Cap 40 generally includes a dome portion 44 and a headband portion
46. Dome portion 44 and headband portion 46 may be individual
chambers defined by the stitching pattern of water wickable thread
42.
[0044] In a further non-limiting embodiment of the present
invention, the cooling garment is a headband as shown in FIG. 8.
Headband 50 includes the above-described cooling fabric in the
areas of headband 50 that contact the front and sides of the
forehead of the wearer. The chambers 54 are defined by the
stitching pattern of water wickable thread 52.
[0045] In a further additional non-limiting embodiment of the
present invention, the cooling garment is a hat as shown in FIG. 9.
Hat 60 may be entirely constructed of the above-described cooling
fabric. Hat 60 generally includes a dome portion 44, a headband
portion 66, ear flap portions 67, and back flap portion 68. The
chambers in hat 60 are defined by the stitching pattern of water
wickable thread 62.
[0046] In another non-limiting embodiment of the present invention,
the cooling garment may be a fourth vest as shown in FIG. 10.
Fourth vest 70 includes the above-described cooling fabric in the
areas of fourth vest 70 that contact the shoulders, upper back, and
lower torso of the wearer. Chambers 74 extend laterally and are
defined by the stitching pattern of water wickable thread 72.
Fourth vest 70 may be closed by fastening a VELCRO.RTM. fastener
76.
[0047] In the above-described cooling fabric, the upper layer and
the lower layer may be made using any suitable water-resistant
fabric. Suitable water-resistant fabrics of the upper layer and the
lower layer may independently include, but not be limited to,
fabrics containing one or more fibers selected from polyamides,
polyesters, polyurethanes, vinyl, acrylic, fluoropolymers, and
aramid materials.
[0048] Specific examples of suitable fibers and fabrics that may be
used to make the upper layer and/or the lower layer of the cooling
fabric include, but are not limited to, the segmented polyurethanes
available under the trade name Lycra.RTM. from E. I. du Pont de
Nemours and Company, Wilmington, Del.; the solution dyed polyester
fabric with a urethane coating available as Sur Last.TM. all
weather fabric from Sur Last, Indianapolis, Ind.; the coated
fabrics available under the name Hydro-No from Norsk Hydro, Oslo,
Norway; Power-Tex.RTM. available from GLAMORISE FOUNDATIONS, INC.,
New York, N.Y.; Ultrex.RTM. available from Burlington Performance
Wear, GREENSBORO, N.C.; nylon or polyester coated with a
polyurethane-based coating available as Hydroflex.RTM. from
Consoltex, Saint-Laurent, Quebec; Demizax.RTM., H2OFF.RTM.,
REPLEX.RTM., and Entrant G-11.RTM. materials available from Toray
Industries, Inc., New York, N.Y.; the Fluoro Carbon fiber
Toyoflon.TM. available from ToRay Industries; the Aramid fibers
Kevlar.RTM. and NOMEX.RTM. available from DuPont; ARAFLEX.RTM.
available from Second Chance Body Armor, Inc., Central Lake, Mich.;
Twaron.RTM. available from AKZO NOBEL, Inc.; BASOFIL.RTM. fibers
commercially available from BASF, Charlotte, N.C.; the
poly(p-phenylene-2,6-benzobisoxazole) (PBO) sold under the
trademark ZYLON.RTM. by Toyobo Co. Ltd., Osaka, Japan; and
composites such as those described in U.S. Pat. No. 6,261,678 to
von Fragstein et al.
[0049] In an embodiment of the present invention, the fabrics used
to make the upper layer and the lower layer of the cooling fabric
are comprised of one or more fabrics containing fibers comprised of
materials selected from polyamides, polyesters, polyurethanes,
vinyl, acrylic, fluoropolymers, aramid,
poly(p-phenylene-2,6-benzobisthiazole), and
poly(p-phenylene-2,6-benzobisoxazole).
[0050] The fabrics used to make the upper layer and the lower layer
of the cooling fabric and/or the lower layer of the cooling fabric
may have any suitable thread count. As used herein and in the
claims, the term "thread count" is the number of horizontal and
vertical threads in one square inch of fabric. The fabrics of the
present invention may have a thread count of at least 50, in some
cases at least 70, in other cases at least 80, and in other cases
at least 100 threads per square inch. Further, the fabrics of the
present invention may have a thread count of up to 350, in some
cases up to 300, in other cases up to 250, in some situations up to
200, and in other situations up to 150 threads per square inch. The
thread count of the fabrics in the upper layer and in the lower
layer may vary between any of the values recited above.
[0051] The fabrics used to make the upper layer and the lower layer
of the cooling fabric and/or the lower layer of the cooling fabric
may have any suitable degree of thickness or fineness. The fineness
of a fabric is measured by its denier, a unit of fineness equal to
the fineness of a fiber weighing one gram for each 9000 meters. A
fiber of <100 denier is finer than a 150 denier fiber.
[0052] The water-resistant fabric of the upper layer and the lower
layer has a total denier of at least 30, in some situations at
least 40, in other situations at least 50, in some cases at least
60, and in other cases at least 70. The total denier of the
water-resistant fabric may be up to 500, in some cases up to 400,
in other cases up to 300, in some situations up to 200, and in
other situations up to 100. When the total denier is too low, the
properties of the fabric may be unsatisfactory. The total denier of
the water-resistant fabrics in the upper layer and in the lower
layer may vary between any of the values recited above.
[0053] In general, the denier of a single fiber used in the
water-resistant fabric is at least 1, in some cases at least 2, in
other cases at least 3, and in some situation at least 4. Further,
the denier of a single fiber used in the water-resistant fabric may
be up to 15, in some cases up to 12, in other cases up to 10, and
in other cases up to 8. The denier of a single fiber used in the
water-resistant fabrics in the upper layer and in the lower layer
may vary between any of the values recited above.
[0054] Typically, the strength of a single fiber used in the
water-resistant fabric is at least 0.5 g/denier, in some cases at
least 1 g/denier, and in other cases at least 2 g/denier or
more.
[0055] In an embodiment of the present invention, the
water-resistant fabric of the upper and/or lower layers has a
Moisture Vapor Transmission Rate (MVTR) of less than 500 g/m.sup.2
per 24 hours, in some cases less than 400 g/m.sup.2 per 24 hours,
in other cases less than 300 g/m.sup.2 per 24 hours, in some
situations less than 200 g/m.sup.2 per 24 hours, and in other
situations less than 100 g/m.sup.2 per 24 hours. If the MVTR is too
high, the superabsobent polymer may dehydrate (lose its water
content) too quickly and require re-hydration too frequently.
Additionally, although not required, it may be desirable that the
water-resistant material have some measurable MVTR, so that the
cooling fabric and/or cooling garments containing the cooling
fabric may be dried (the superabsorbent polymer dehydrated) when
desired. As such, the water-resistant fabric of the upper and lower
layers may have an MVTR of at least 0.1 g/m.sup.2 per 24 hours, in
some cases at least 1 g/m.sup.2 per 24 hours, in other cases at
least 5 g/m.sup.2 per 24 hours, in some situations at least 10
g/m.sup.2 per 24 hours, and in other situations at least 25
g/m.sup.2 per 24 hours. The MVTR of the water-resistant fabric of
the upper layer and/or lower layer may vary between any of the
values recited above.
[0056] As used herein and in the claims, the MVTR of the
water-resistant fabric is determined by the following procedure.
Approximately 70 ml of a solution consisting of 35 parts by weight
of potassium acetate and 15 parts by weight of distilled water are
placed into a 133 ml polypropylene cup having an inside diameter of
6.5 cm at its mount. An expanded polytetrafluoroethylene (PTFE)
film having a minimum MVTR of approximately 60,000 g/m.sup.2 per 24
hours as tested by the method described in U.S. Pat. No. 4,862,730
to Crosby using potassium acetate and available from W. L. Gore
& Associates, Inc. of Newark, Del. is heat sealed to the lip of
the cup to create a taut, leakproof, microporous barrier containing
the solution. A similar expanded PTFE film was mounted to the
surface of a water bath. The water bath assembly is controlled at
23.+-.0.2.degree. C. utilizing a temperature-controlled roll and a
water circulating bath. The sample to be tested is allowed to
condition at a temperature of 23.degree. C. and a relative humidity
of 50% prior to performing the test procedure. Samples are placed
so that the water-resistant fabric to be tested is in contact with
the expanded polytetrafluoroethylene film mounted to the surface of
the water bath and an equilibration of at least 15 minutes is used
prior to the introduction of the cup assembly. The cup assembly is
weighed to the nearest 0.001 g and is placed in an inverted manner
onto the center of the test sample. Water transport is provided by
the driving force between the water in the water bath and the
saturated salt solution providing water flux by diffusion in that
direction. The sample is tested for 15 minutes and the cup assembly
is then removed and weighed again. The MVTR is calculated from the
weight gain of the cup assembly and expressed in grams of water per
square meter of sample surface area per 24 hours.
[0057] In a particular embodiment of the present invention, the
cooling fabric used for one or both of the upper layer and the
lower layer is a fabric that includes a substrate fabric, which may
include any of the fabrics or fiber based materials described
above, and a water-resistant coating layer formed from a
water-resistant coating composition over at least a portion of a
surface of the substrate fabric. Any suitable coating composition
can be used to form the coating layer. Suitable coating
compositions include, but are not limited to, those that include
one or more water-resistant materials selected from natural rubber,
synthetic rubber, silicone rubber, fluoropolymers, polyurethanes,
and acrylics.
[0058] In an embodiment of the present invention, a coated fabric
useful as either or both of the upper layer and the lower layer is
produced as follows. First, a woven fabric is constructed or
obtained that is suitable for use in the present cooling fabric. As
described above, the fabric may be made from any of the suitable
materials described above. Prior to applying a water-resistant
composition, the fabric may be scoured. When scoured, the material
may be scoured with an alkaline solution.
[0059] In some cases, after being scoured, the fabric is put on a
tenter frame, dried and heat set. In some situations, it is
advantageous that the fabric be substantially dry and free of
moisture prior to being treated with the water-resistant
composition. As a non-limiting example, the fabric may be dried so
that the moisture level is substantially equivalent to the natural
moisture level of the fibers used to make the fabric. For many
fibers, the moisture level should be less than 10%, and in some
cases less than 7%.
[0060] After the fabric has been dried and heat set, the
water-resistant composition is applied to at least one side of the
fabric. The composition may be sprayed on the fabric, printed on
the fabric, and/or the fabric is dipped into a bath containing the
water-resistant composition in solution, dispersion, or emulsion
form.
[0061] After the water-resistant composition is applied to the
fabric, the fabric may be heated to a temperature sufficient for
the coating to dry and/or cure. Once the water-resistant
composition has been sufficiently heat treated, the fabric may be
used in constructing the cooling garments in accordance with the
present invention.
[0062] The water-resistant materials can be combined in water with
a drying agent such as an alcohol and an emulsifier. The amount of
the water-resistant composition applied to the fabric will depend
upon the particular formulation and the particular application
method.
[0063] In an embodiment of the present invention, the
water-resistant material comprises a fluorocarbon, an acrylic
polymer, and/or a polyurethane.
[0064] When the cooling fabric used for one or both of the upper
layer and the lower layer is a fabric and includes a substrate
fabric coated by a water-resistant coating layer, the substrate
fabric may comprise one or more fabrics containing fibers comprised
of materials selected from cotton, wool, polyamides, polyesters,
polyurethanes, vinyl, acrylic, fluoropolymers, aramid,
poly(p-phenylene-2,6-benzobisthiazole), and
poly(p-phenylene-2,6-benzobisoxazole) or any other fabric described
above.
[0065] As was indicated above, a water wickable thread may be used
to sew and/or stitch the upper layer and the lower layer together
to form a plurality of chambers. Any suitable water wickable thread
may be used in the present invention. Examples of suitable
materials from which the wickable thread may be made include, but
are not limited to, cotton, wool, hemp, copolyetheresters,
polyesters, polyethers, and mixtures thereof.
[0066] The chambers formed in the present cooling garments may be
dimensioned to form any suitable type of shape. Suitable shapes
include, but are not limited to, squares, rectangles, triangles,
circles, and ovals, as well as non-descriptive shapes, so long as
the stitching forms a continuous barrier to contain and hold the
superabsorbent polymer in place. The shape of the chambers may be
dimensioned to encompass an area in the upper layer and/or the
lower layer of at least 1 mm.sup.2, in some cases at least 2
mm.sup.2, in other cases at least 3 mm.sup.2, in some situations at
least 5 mm.sup.2, and in in other situations at least 10 mm.sup.2.
When the area of the chambers are too small, the cooling fabric may
have poor heat transfer properties. Further, the chambers may be
dimensioned to encompass an area of up to 60 mm.sup.2, in some
cases up to 55 mm.sup.2, in other cases up to 50 mm.sup.2, in some
situations up to 45 mm.sup.2, in other situations up to 40
mm.sup.2, in some circumstances up to 35 mm.sup.2, and in other
circumstances up to 25 mm.sup.2. When the area of the chambers is
too large, the superabsorbent polymer particles may settle to the
lower portions of the chamber and provide insufficient heat
transfer properties to the cooling garment. The chambers of the
cooling garment may have an area between any range of values
inclusive of those stated above.
[0067] In a particular embodiment of the present invention, the
water-resistant fabric of the upper layer and/or the lower layer
comprises nylon, has a 70.times.70 warp/filling, has a 104.times.86
thread count, has one side coated by a coating composition
comprising a polyurethane, and the other side coated by a coating
composition comprising an acrylic polymer. In this embodiment,
either side may be the side in contact with the superabsorbent
polymer and either side may be the side in contact with skin,
clothing or the atmosphere.
[0068] As indicated above, the chambers contain a superabsorbent
polymer. Any suitable superabsorbent polymer may be used in the
present cooling garment. Suitable superabsorbent polymers include,
but are not limited to, natural gums, cellulosics, synthetic
hydrogel polymers, and mixtures thereof.
[0069] In an embodiment of the present invention, the natural gums
useful as superabsorbent polymers may be selected without
limitation from xanthan, guar, agar, pectin, gum arabic, locust
bean gum, hydroxypropyl guar gum, polyglucomannan gum, cationic
guar gum, anionic guar gum, alginate, irish moss, and gum arabic.
The cellulosics useful as superabsorbent polymers may be selected
without limitation from methyl cellulose, ethyl cellulose,
carboxymethyl cellulose, carboxy ethyl cellulose, hydroxyethyl
cellulose, hydroxymethyl cellulose, and hydroxypropylcellulose. The
synthetic hydrogel polymers useful as superabsorbent polymers may
be selected without limitation from suitable crosslinked,
water-swellable acrylic copolymers.
[0070] In a particular embodiment of the present invention, the
synthetic hydrogel polymers include, but are not limited to,
copolymers that include repeat units from one or more monomers
selected from (meth)acrylic acid, maleic acid,
2-(meth)acrylamido-2-methyl propane sulfonic acid, styrene
sulfonate, vinyl sulfonic acid, and their corresponding ammonia,
amine and alkali metal salts, (meth)acrylamide, vinyl alcohol,
vinyl acetate, maleic anhydride, alkyl vinyl ethers,
vinylmorpholinone, vinylpyrridine, vinyl pyrrolidone, and
acrylonitrile; and one or more crosslinking agents selected from
N,N'-methylenebis(meth)- acrylamide, (poly)ethylene glycol
di(meth)acrylate, (poly)propylene glycol di(meth)acrylate,
trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate,
glycerol acrylate methacrylate, ethylene-oxide-modified
trimethylolpropane tri(meth)acrylate, pentaerythritol
tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, triallyl
cyanurate, triallyl isocyanurate, triallyl phosphate,
triallylamine, poly(meth)allyloxyalkanes, (poly)ethylene glycol
diglycidyl ether, glycerol diglycidyl ether, ethylene glycol,
polyethylene glycol, propylene glycol, glycerol, pentaerythritol,
ethylenediamine, ethylene carbonate, propylene carbonate,
polyethylenimine, glycidyl (meth)acrylate, diallyl sucrose,
triallyl sucrose triallyl amine, and triallyl methyl ammonium
chloride.
[0071] In another particular embodiment of the present invention,
the superabsorbent polymer comprises a synthetic anionic acrylic
copolymer.
[0072] Additional superabsorbent polymers and methods to
manufacture such polymers are described, without limitation, in
U.S. Pat. No. 6,469,080 to Miyake et al., U.S. Pat. No. 6,399,668
Miyake et al., U.S. Pat. No. 6,127,454 to Wada et al., U.S. Pat.
No. 6,087,002 to Kimura et al., U.S. Pat. No. 5,244,735 to Kimura
et al., U.S. Pat. No. 4,925,603 to Nambu, and U.S. Pat. No.
4,734,478 to Tsubakimoto et al. Non-limiting examples of
superabsorbent polymers that may be used in the present cooling
garment include those available under the trade names ALCOSORB.RTM.
from Ciba Specialty Chemicals, Chatanooga, Tenn.; DRYTECH.RTM. from
the Dow Chemical Company, Midland, Mich.; NORSOCRYL.RTM. and
AQUAKEEP.RTM. from Atofina, Paris, France; HYDROSORB.TM. from
HYDROSORB Inc., Orange, Calif.; and AQUALIC CA from Nippon,
Shokubai Co., Ltd., Osaka, Japan.
[0073] The superabsorbent polymer, when dry, is typically in
particulate form. The particle size of the superabsorbent polymer
particulates are typically at least 20 microns, in some cases at
least 35 microns, in other cases at least 50 microns, and in
certain situations at least 100 microns. It is desirable that the
particle size of the superabsorbent polymer particulates be large
enough that they can be contained in the fabric. Further, the
particle size of the superabsorbent polymer particulates is up to
1,000 microns, in some cases up to 750 microns, in other cases up
to 500 microns, and in certain situations up to 350 microns. If the
particle size of the superabsorbent polymer particulates is too
large, they may take too long to hydrate effectively. The particle
size of the superabsorbent polymer particulates may vary between
any of the values recited above.
[0074] The cooling garment of the present invention may be made
entirely of the cooling fabric described above. Alternatively, the
cooling garment may be constructed in part using the present
cooling fabric and the remainder constructed of any suitable
conventional fabric. Suitable conventional fabrics include, but are
not limited to, those including cotton, wool, nylon, and other
materials known in the art.
[0075] The cooling garments described above, once hydrated (i.e.,
the superabsorbent polymer is hydrated), maintain their moisture
level and cooling capacity for a week or more when left hanging at
ambient conditions. In other words, because of the fabric selection
and/or fabric coating, the fabric is water-resistant and the
superabsorbent polymer particles retain their moisture and do not
dry out as quickly as when non-water-resistant fabrics are used as
the upper layer and/or lower layer of the cooling garment. Further,
moisture, water, or aqueous solutions absorbed by the
superabsorbent polymer do not "wick out" or transfer to the skin or
clothing of the wearer.
[0076] The invention has been described with reference to the
preferred embodiments. Obvious modifications and alterations will
occur to others upon reading and understanding the preceding
detailed description. It is intended that the invention be
construed as including all such modifications and alterations
insofar as they come within the scope of appended claims or the
equivalents thereof.
* * * * *