U.S. patent application number 14/916875 was filed with the patent office on 2016-07-07 for lightweight cooling fabric and articles made therefrom.
The applicant listed for this patent is Matthew KOLMES, Nathaniel KOLMES, James THRELKELD. Invention is credited to Matthew KOLMES, Nathaniel KOLMES, James THRELKELD.
Application Number | 20160194793 14/916875 |
Document ID | / |
Family ID | 52629069 |
Filed Date | 2016-07-07 |
United States Patent
Application |
20160194793 |
Kind Code |
A1 |
KOLMES; Nathaniel ; et
al. |
July 7, 2016 |
LIGHTWEIGHT COOLING FABRIC AND ARTICLES MADE THEREFROM
Abstract
A lightweight knit fabric, has a knit structure prepared from at
least 80 wt % of one or more yarns having a hydrophobic surface
containing less than 1 part hydroxyl group per 10 million parts of
(co)polymer forming the one or more yarns, and articles prepared
therefrom, which provide efficient moisture transport and cooling
effects on a subject in contact therewith.
Inventors: |
KOLMES; Nathaniel; (Hickory,
NC) ; KOLMES; Matthew; (New York, NY) ;
THRELKELD; James; (Indian Trial, NC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KOLMES; Nathaniel
KOLMES; Matthew
THRELKELD; James |
Hickory
New York
Indian Trial |
NC
NY
NC |
US
US
US |
|
|
Family ID: |
52629069 |
Appl. No.: |
14/916875 |
Filed: |
September 6, 2013 |
PCT Filed: |
September 6, 2013 |
PCT NO: |
PCT/US13/58488 |
371 Date: |
March 4, 2016 |
Current U.S.
Class: |
2/115 ; 2/242;
2/243.1; 66/202 |
Current CPC
Class: |
A41B 11/00 20130101;
D10B 2401/021 20130101; D04B 1/16 20130101; A41B 1/08 20130101;
A41B 2400/60 20130101 |
International
Class: |
D04B 1/16 20060101
D04B001/16; A41B 11/00 20060101 A41B011/00; A41B 1/08 20060101
A41B001/08 |
Claims
1. A lightweight knit fabric, comprising a knit structure prepared
from at least 80 wt % of one or more yarns having a hydrophobic
surface containing less than 1 part hydroxyl groups per 10 million
parts of (co)polymer forming the one or more yarns.
2. The lightweight knit fabric of claim 1, wherein the one or more
yarns is a yarn prepared from at least 70 wt % linear low density
polyolefin.
3. The lightweight knit fabric of claim 2, wherein the yarn is
linear low density polyethylene, optionally containing up to 30 wt
% of one or more .alpha.-olefin comonomers.
4. The lightweight knit fabric of claim 3, wherein the one or more
.alpha.-olefin comonomers is at least one member selected from the
group consisting of propylene, n-butene, n-hexane, and
n-octene.
5. The lightweight knit fabric of claim 3, wherein the one or more
.gamma.-olefin comonomers is present in an amount of 10 to 30 wt %,
based on total yarn weight.
6. The lightweight knit fabric of claim 2, wherein the linear low
density polyolefin has a weight average molecular weight of 10,000
or more.
7. The lightweight knit fabric of claim 1, wherein the one or more
yams has no surface hydroxyl groups.
8. The lightweight knit fabric of claim 1, wherein the knit fabric
is made using a linear stitch or a jersey stitch.
9. The lightweight knit fabric of claim 1, wherein the fabric has a
fabric weight of 10 ounces per square yard (OPSY).
10. The lightweight knit fabric of claim 1, wherein the fabric
comprises up to 4 wt % of an elastomeric yarn.
11. The lightweight knit fabric of claim 6, wherein the linear low
density polyolefin is linear low density polyethylene, optionally
containing up to 30 wt % of one or more .alpha.-olefin
comonomers.
12. An article prepared from the lightweight knit fabric of claim
1.
13. The article of claim 12, wherein the article is a garment.
14. The article of claim 13, wherein the garment is a member
selected from the group consisting of shirts, undergarments, socks,
leggings, and tights.
15. The article of claim 13, wherein the garment is a shirt.
16. The article of claim 14, wherein the shirt is a short-sleeved
shirt.
17. The article of claim 14, wherein the shirt is a long-sleeved
shirt.
18. The article of claim 12, wherein the article is a member
selected from bed sheets, pillowcases, and bandages.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a lightweight fabric that
provides cooling effects to the wearer, and to articles made
therefrom.
[0003] 2. Description of the Related Art
[0004] Heat exhaustion is a problem that affects human beings in a
variety of occupations and environments around the world. According
to Joseph Rampulla, MS, APRN, BC "Heat illness is generally
underreported, and the true incidence is unknown. Death rates from
other causes (e.g. cardiovascular, respiratory) increase during
heat waves but are generally not reflected in the morbidity and
mortality statistics related to heat illness. Nonetheless, heat
waves account for more deaths than all other natural disasters
combined in the USA." From police and paramedics to construction
workers and laborers, or service men and women engaging in
strenuous exercise and physical training, hot and humid conditions
degrade performance abilities and lead to injuries, fainting, and
other more serious medical conditions.
[0005] Most of the available products today use lightweight
polyester material with a finish that wicks moisture to create a
lightweight fabric that will wick moisture away from the body. This
creates a material that has some properties that will keep you cool
(wicking pulls sweat away from your skin). While polyester is a
durable fiber, it does best to insulate your body in cold
temperatures. Fabrics and shirts made from polyester, with a
wicking finish are readily available from every major sportswear
company. The effectiveness of these polyester wicking fabrics at
keeping your body comfortable in heat and humidity is minimal and
quickly dissipates as the fiber becomes overloaded with body heat
and perspiration.
[0006] Accordingly, a lightweight fabric is needed that will
provide high levels of wicking, and result in highly efficient
cooling of the wearer.
SUMMARY OF THE INVENTION
[0007] Accordingly, one object of the present invention is to
provide a lightweight fabric that provides a wicking effect to more
efficiently transport moisture, preferably coupled with an
extremely high rate of evaporation, which provides a cooling effect
on a subject in contact with the fabric.
[0008] A further object of the present invention is to provide an
article formed from the present invention fabric, which keeps the
wearer dry and cool even during strenuous activity.
[0009] Another object of the present invention is to provide an
article formed from the present invention fabric, which can be used
in bed linens or bandages, particularly for treatment of burn
victims, which will not adhere to burned tissue, and provides a
cooling effect on the subject in contact therewith.
[0010] These and other objects of the present invention, alone or
in combinations thereof, have been satisfied by the discovery of a
lightweight knit fabric, comprising a knit structure prepared from
at least 80 wt % of one or more yarns having a hydrophobic surface
containing less than 1 part hydroxyl group per 10 million parts of
(co)polymer forming the yarn, and articles prepared therefrom.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A more complete appreciation of the invention and many of
the attendant advantages thereof will be readily obtained as the
same becomes better understood by reference to the following
detailed description when considered in connection with the
accompanying drawings, wherein:
[0012] FIG. 1 shows a graph of drying times comparing a shirt in
accordance with the present invention compared to three
commercially available alternative shirts, and showing significant
improvements in drying time for the present invention shirt.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The term "fiber" as used herein refers to a fundamental
component used in the assembly of yarns and fabrics. Generally, a
fiber is a component which has a length dimension which is much
greater than its diameter or width. This term includes ribbon,
strip, staple, and other forms of chopped, cut or discontinuous
fiber and the like having a regular or irregular cross section.
"Fiber" also includes a plurality of any one of the above or a
combination of the above.
[0014] As used herein, the term "high performance fiber" means that
class of synthetic or natural non-glass fibers having high values
of tenacity greater than 10 g/denier, such that they lend
themselves for applications where high abrasion and/or cut
resistance is important. Typically, high performance fibers have a
very high degree of molecular orientation and crystallinity in the
final fiber structure.
[0015] The term "filament" as used herein refers to a fiber of
indefinite or extreme length such as found naturally in silk. This
term also refers to manufactured fibers produced by, among other
things, extrusion processes. Individual filaments making up a fiber
may have any one of a variety of cross sections to include round,
serrated or crenular, bean-shaped or others.
[0016] The term "yarn" as used herein refers to a continuous strand
of textile fibers, filaments or material in a form suitable for
knitting, weaving, or otherwise intertwining to form a textile
fabric. Yarn can occur in a variety of forms to include a spun yarn
consisting of staple fibers usually bound together by twist; a
multi filament yarn consisting of many continuous filaments or
strands; or a mono filament yarn which consists of a single strand.
A "blended yarn" as used herein refers to a yarn that comprises an
intimate blend of at least two different types of fibers.
[0017] The term "composite yarn" refers to a yarn prepared from two
or more yarns, which can be the same or different. Composite yarn
can occur in a variety of forms wherein the two or more yarns are
in differing orientations relative to one another. The two or more
yarns can, for example, be parallel, wrapped one around the
other(s), twisted together, or combinations of any or all of these,
as well as other orientations, depending on the properties of the
composite yarn desired. Examples of such composite yarns are
provided in U.S. Pat. No. 4,777,789, U.S. Pat. No. 4,838,017, U.S.
Pat. No. 4,936,085, U.S. Pat. No. 5,177,948, U.S. Pat. No.
5,628,172, U.S. Pat. No. 5,632,137, U.S. Pat. No. 5,644,907, U.S.
Pat. No. 5,655,358, U.S. Pat. No. 5,845,476, U.S. Pat. No.
6,212,914, U.S. Pat. No. 6,230,524, U.S. Pat. No. 6,341,483, U.S.
Pat. No. 6,349,531, U.S. Pat. No. 6,363,703, U.S. Pat. No.
6,367,290, and U.S. Pat. No. 6,381,940 (collectively, the "Kolmes
patents"), the contents of each of which are hereby incorporated by
reference.
[0018] For convenience, the term "yarn component" as used herein,
encompasses fiber, monofilament, multifilament and yarn.
[0019] The present invention relates to a lightweight fabric
comprising a knit structure prepared from at least 80 wt % of one
or more yarns having a hydrophobic surface containing less than 1
part hydroxyl groups on the surface of the yarn per 10 million
parts of (co)polymer forming the one or more yarns. Preferably, the
fabric has a fabric weight of less than 10 ounces per square yard
(OPSY), more preferably less than 6 OPSY, most preferably less than
5 OPSY. The knit fabric is preferably formed from at least 85 wt %
of the one or more yarns having the hydrophobic surface, more
preferably at least 90 wt % of the one or more yarns having the
hydrophobic surface, most preferably 95-100 wt % of the one or more
yarns having the hydrophobic surface. Ideally, and in a most
preferred embodiment, the one or more yarns having the hydrophobic
surface is a linear low density polyethylene (LLDPE) yarn, which
can optionally contain one or more comonomers such as other alpha
olefins.
[0020] The lightweight knit fabric of the present invention
preferably has the one or more yarns being a yarn prepared from at
least 70 wt % linear low density polyolefin. More preferably, the
yarn is linear low density polyethylene, optionally containing up
to 30 wt % of one or more .alpha.-olefin comonomers. The one or
more .alpha.-olefin comonomers are preferably at least one member
selected from the group consisting of propylene, n-butene,
n-hexane, and n-octene. When present, the one or more
.alpha.-olefin comonomers is preferably present in an amount of 10
to 30 wt %, based on total yarn weight.
[0021] In the present invention, the linear low density polyolefin
preferably has a weight average molecular weight of 10,000 or
more.
[0022] In a most preferred embodiment, the one or more yarns making
up the present invention fabric have no surface hydroxyl
groups.
[0023] The lightweight knit fabric of the present invention is
preferably made using a linear stitch or a jersey stitch.
[0024] In order to provide form fitting properties to the
lightweight fabric of the present invention, the fabric can
optionally comprise up to 4 wt %, preferably 2-4 wt %, more
preferably 3 wt %, of an elastomeric yarn, so long as the
elastomeric yarn does not interfere with the moisture transport and
cooling properties of the fabric.
[0025] Several factors are important when trying to design a
cooling and wicking fabric according to the present invention:
[0026] It is important for the fabric to be form fitting in order
to keep the skin as dry as possible to keep the skin cool;
[0027] It is important not to let water bond to the material, by
maintaining a hydrophobic surface of the yarn used in making the
garment or article (shirt, headband, etc.,); and
[0028] It is important not to let the material absorb sweat.
[0029] If sweat pools on the skin, it then blocks the transport of
the sweat to the outside of the shirt and the body will still be
hot and uncomfortable even if the shirt is cool on the outside.
Moisture must be evaporated from the skin rather than from the
shirt to keep the skin cool.
[0030] The present invention yarn is made from a (co)polymer
designed by its constituents to be hydrophobic. The filaments in
the fiber bundle are designed to maximize the volume of the
copolymer while minimizing the surface area of the filament
consistent with good hand (comfort) on the fabric while achieving
the smallest amount of surface area possible in the fiber bundle.
There should be space in the fabric to allow the sweat to travel to
the surface of the apparel. The copolymer is formulated to have
almost no hydroxyl groups on the surface of the copolymer that
would bond with the water molecules contained in perspiration. The
bonded water is harder to remove from the copolymer and that is
typically what keeps fabrics wet, thus keeping the skin wet and
decreasing the evaporation rate. It is academic that "bound water"
takes extra energy to transport and evaporate, therefore,
eliminating the hydroxyl groups from the copolymer allows for
faster transportation and evaporation of sweat away from the body.
This prevents the "water logging" effect and allows the cooling to
be continuous. Thus, some conventional cooling shirts are able to
cool for a short time until the "water logging" effect takes over
which effectively stops the cooling. The present invention fabric,
on the other hand, provides both a rapid transport of water from
the skin, and a rapid drying of the water from the surface of the
fabric in order to maintain the drying and cooling properties over
the course of wearing or using the article made from the
fabric.
[0031] The present invention fabric is also perfect for bandages,
sheets, and pillowcases, and for burn victim treatment because the
fiber will not absorb fluids and wicks moisture away from wounds.
Further, particularly for burn victims, the fabric of the present
invention does not adhere to wounds, thus adding to comfort, and
providing a cooling feeling to the site of the burn. Thus, the
present invention fabric has unlimited applications in the areas of
apparel, bedding, and health and safety.
[0032] In the present invention, the fabric can be formed into
articles, preferably into an article selected from the group
consisting of garments, bed sheets, pillowcases, and bandages. When
the article is a garment, it is preferably a member selected from
the group consisting of shirts, undergarments, socks, leggings,
biking pants/shorts and tights. When the garment is a shirt, it can
be either short-sleeved or long-sleeved, and when the garment is
biking pants it can be either long legged or shorts.
[0033] The present invention fabric is prepared primarily from
fibers having less than 1 part hydroxyl groups in the copolymer per
10 million parts of copolymer/fiber, particularly on the fiber
surface. Preferably, the fiber has no hydroxyl groups in the
copolymer, unlike cotton, polyester, nylon and wool. Therefore, the
present invention fabric has excellent moisture transport and
evaporation, which is superior to other available fabrics. The skin
is kept drier and therefore is cooler.
[0034] Linear low-density polyethylene (LLDPE) is typically a
substantially linear polymer (polyethylene), with significant
numbers of short branches, commonly made by copolymerization of
ethylene with longer-chain olefins. These other comonomers can be
present in amounts up to 30 wt % of the polymer, preferably from
10-30 wt % of the polymer. Linear low-density polyethylene differs
structurally from conventional low-density polyethylene (LDPE)
because of the absence of long chain branching. The linearity of
LLDPE results from the different manufacturing processes of LLDPE
and LDPE. In general, LLDPE is produced at lower temperatures and
pressures by copolymerization of ethylene and such higher
alpha-olefins as butene, hexene, or octene. The copolymerization
process produces an LLDPE polymer that has a narrower molecular
weight distribution than conventional LDPE and in combination with
the linear structure, significantly different rheological
properties. LLDPE yarn is commercially available from a variety of
manufacturers, such as Fiber Science, Inc. The LLDPE yarn for use
in the present invention is typically a multifilament yarn, having
a total denier of 70 to 300, preferably 150 to 200.
[0035] If desired, in order to modify the physical properties of
the fabric of the present invention, it is possible to include up
to 20 wt % of one or more other types of yarn, so long as the one
or more other yarns do not contain hydrophilic surfaces sufficient
to detract from the wicking and cooling properties of the present
invention. Most preferably, no other type of yarn is used in the
fabric of the present invention, with the exception of thread used
to stitch parts of the fabric together at the seams. In a
particularly preferred embodiment, a garment formed from the
present invention fabric is formed by shaped knitting (knitting
that uses dropped stitches in order to generate a garment in a
particular shape, with minimal seams in construction).
[0036] If the one or more additional yarns are included, the yarn
can be any of a variety of types of yarn. One type of yarn that may
be present is an elastomeric yarn if desired. As the elastomeric
yarn component, any elastomeric fiber may be used, as monofilament
or multifilament yarn. However, due to the hydrophilicity of the
surface of typical elastomeric yarns, their use should be kept at a
minimum if at all possible. An elastomer is a natural or synthetic
polymer that, at room temperature, can be stretched and expanded to
typically twice its original length. After removal of the tensile
load it will immediately return to its original length. Along with
spandex, rubber and anidex (no longer produced in the United
States) are considered elastomeric fibers. Spun from a block
copolymer, spandex fibers exploit the high crystallinity and
hardness of polyurethane segments, yet remain "rubbery" due to
alternating segments of polyethylene glycol. Suitable elastomeric
fibers include, but are not limited to, fibers made from copolymers
having both rigid and flexible segments in the polymer chains, such
as, for example, block copolymers of polyurethane and polyethylene
glycol. Particularly suitable elastomeric fibers include, but are
not limited to, Spandex, such as LYCRA (produced by United Yarn
Products), ELASPAN (produced by Invista), DORLASTAN (produced by
Bayer), CLEAR SPAN (produced by Radici) and LINEL (produced by
Fillattice).
[0037] Elastomeric yarns can have one or more of the following
materials properties: can be stretched over 500% without breaking;
able to be stretched repetitively and still recover original
length; lightweight; abrasion resistant; poor strength, but
stronger and more durable than rubber; soft, smooth, and supple;
resistant to body oils, perspiration, lotions, and detergents; no
static or pilling problem; very comfortable; and easily dyed.
[0038] The elastomeric yarn can be any desired denier, preferably
from 10 to 210, more preferably from 15 to 150, most preferably
from 20 to 75. The elastomeric yarn can be used alone or combined
with one or more other yarns of any desired type, so long as the
combination retains its elastomeric properties. If combined with
one or more other yarns, the elastomeric yarn and other yarns are
preferably blended, or the one or more other yarns are wrapped
around the elastomeric yarn to provide an elastomeric core
composite yarn, thus retaining the stretch property.
[0039] Elastomeric yarn containing composite yarns are further
described in U.S. Pat. Nos. 5,568,657 and 5,442,815, the contents
of which are incorporated herein by reference. Elastomeric yarn
containing composite yarns having wicking properties are described
in U.S. Provisional Application Serial No. 61/020,790, filed Jan.
14, 2008, the contents of which are hereby incorporated by
reference.
[0040] If high strength, tenacity and/or cut resistance are
desired, it is also possible to include small amounts of a high
performance fiber in the present invention fabric. The high
performance fiber can be any desired high performance fiber.
However, from the point of view of maintaining the hydrophobic
surface of the yarn in the fabric, the high performance fiber
preferably comprises a high molecular weight polyolefin, preferably
high molecular weight polyethylene or high molecular weight
polypropylene.
[0041] U.S. Pat. No. 4,457,985, hereby incorporated by reference,
generally discusses high molecular weight polyethylene and
polypropylene fibers. In the case of polyethylene, suitable fibers
are those of molecular weight of at least 150,000, preferably at
least 400,000, more preferably at least one million and most
preferably between two million and five million. Such extended
chain polyethylene (ECPE) fibers may be grown in solution as
described in U.S. Pat. No. 4,137,394 or U.S. Pat. No. 4,356,138,
hereby incorporated by reference, or may be a filament spun from a
solution to form a gel structure, as described in German Off. 3 004
699 and GB 2 051 667, and especially described in U.S. Pat. No.
4,551,296, hereby incorporated by reference. As used herein, the
term polyethylene preferably means a predominantly linear
polyethylene material that may contain minor amounts of chain
branching or comonomers not exceeding 5 modifying units per 100
main chain carbon atoms, and that may also contain admixed
therewith not more than about 50 weight percent of one or more
polymeric additives such as alkene-1-polymers, in particular low
density polyethylene, polypropylene or polybutylene, or copolymers
containing mono-olefins as primary monomers. Depending upon the
formation technique, the draw ratio and temperatures, and other
conditions, a variety of properties can be imparted to these
fibers. The tenacity of the fibers should preferably be at least 15
g/d, more preferably at least 20 g/d, even more preferably at least
25 g/d and most preferably at least 28 g/d. Similarly, the tensile
modulus of the filaments, as measured by an Instron tensile testing
machine, is preferably at least 300 g/d, more preferably at least
500 g/d and still more preferably at least 1,000 g/d and most
preferably at least 1,200 g/d. These highest values for tensile
modulus and tenacity are generally obtainable only by employing
solution grown or gel fiber processes. For example, high molecular
weight polyethylene filaments produced commercially by Honeywell
Corp. under the trade name SPECTRA or by DSM under the trade name
DYNEEMA and having moderately high moduli and tenacity are
particularly useful.
[0042] Similarly, highly oriented polypropylene of molecular weight
at least 200,000, preferably at least one million and more
preferably at least two million, may be used. Such high molecular
weight polypropylene may be formed into reasonably well oriented
fibers by techniques described in the various references referred
to above, and especially by the technique of U.S. Pat. Nos.
4,663,101 and 4,784,820, hereby incorporated by reference, and U.S.
patent application Ser. No. 069,684, filed Jul. 6, 1987 (see
published application WO 89 00213). Since polypropylene is a much
less crystalline material than polyethylene and contains pendant
methyl groups, tenacity values achievable with polypropylene are
generally substantially lower than the corresponding values for
polyethylene. Accordingly, a suitable tenacity is at least about 8
g/d, with a preferred tenacity being at least about 11 g/d. The
tensile modulus for polypropylene is at least about 160 g/d,
preferably at least about 200 g/d.
[0043] The high performance yarn can be any desired denier,
preferably from 10 to 325, more preferably from 50 to 250, most
preferably from 100 to 220.
[0044] The present invention fabric and articles produced therefrom
provide a noticeable and remarkable cooling effect on a person
touching or wearing the articles. The present invention fabric has
been found to dry nearly four times faster than typical
commercially available "cool t-shirts" in laboratory tests. The
present invention fabric is made from a fiber that transmits water
from the skin to the outer surface of the t-shirt in an extremely
efficient way that is far superior to cotton or polyester because
the wicking ability is due to the structure, and particularly the
surface properties, of the fiber from which the fabric/article is
made. This wicking coupled with rapid evaporation on the surface of
the fabric translates into remarkably cool t-shirts and apparel
that keep personnel comfortable during work and exercise or when
used as bandages, or bedding as sheets and pillowcases. The
performance advantage over typical so-called polyester "cooling
t-shirts" is twofold: the present invention fabric achieves
superior cooling by transporting and evaporating moisture at an
exceptionally high rate, and the present invention fabric
technology does not trap and hold heat like polyester. In fact, the
present invention yarn is up to 45% lighter than polyester.
[0045] An embodiment of the present invention fabric (having a
fabric weight of 6 OPSY, prepared from 100% LLDPE yarn) was
prepared and tested for drying time against three commercially
available products, a 100% cotton shirt, a shirt sold by
DeFeet.RTM. under the brand name UND-ICE EXTREME, a shirt sold by
UnderArmour.RTM. under the brand name COLD BLACK, and made
predominantly from polyester. The drying conditions were at a room
temperature of 69.8.degree. F., and a relative humidity of 15.5%.
In the graph shown in FIG. 1, the present invention t-shirt dried
approximately four times faster than the UnderArmor shirt. The only
product even close to the present invention is the DeFeet.RTM.
shirt, which is a predecessor product made by the present applicant
for DeFeet.RTM.. None of the comparative shirts tested contain the
LLDPE based fabric of the present invention. One factor that is
important to obtaining the present invention cooling effect (in a
garment) is that the garment fits properly. Although this seems
elementary, it is noteworthy that improperly fitting t-shirts will
pool the sweat on the skin and thereby prevent cooling.
Accordingly, garments made from the present invention fabric are
preferably designed to be thin, and therefore minimize the
insulation (of the fabric) from interfering with the cooling
feeling from the evaporation of the sweat, and are designed to be
substantially form fitting, in order to maintain at least a minimum
level of contact with the skin of the wearer, in order to enable
the wicking properties of the fabric to act most efficiently. This
fabric can be made into under garments, helmet liners, sleeves,
socks, bedding and other apparel items.
[0046] The present invention fabric was also tested for cooling
ability. A preferred embodiment of the present invention fabric was
prepared into a biking shirt (having fabric weight of 6 OPSY, and
formed from 100% LLDPE, except for the thread stitching seams
together). The shirt was compared to a commercially available
biking shirt having a similar fabric weight as the present
invention shirt. The shirts were each individually worn by a
bicyclist on a stationary bike in an ambient temperature controlled
environment, with temperature measurements taking at mid-chest
level using thermal imaging. With the help of a power/wattage meter
hooked to the stationary bike, the subject was pedaling at an equal
effort for four separate sessions and the images were shot after 5
minutes of exercise, wearing each shirt, with and without a fan
blowing on the biker. The commercially available product product
was shot after 5 minutes of work with no air movement and 5 minutes
of work with a fan blowing at 5 mph directly at the subject. The
same scenario was done for the present invention product. The
comparative shirt at 5 minutes with no fan gave a temperature
reading of 82.6.degree. F., while the present invention product at
5 minutes with no fan gave a temperature reading of 79.8.degree. F.
The comparative shirt at 5 minutes with fan gave a temperature
reading of 79.7.degree. F., while the present invention product at
5 minutes with fan gave a temperature reading of 70.9.degree. F.
This corresponds to a temperature reduction with fan using the
present invention product of 11%, compared to a reduction of only
3.5% for the comparative shirt! The present invention fabric
provided significantly improved cooling, with or without fan, with
the subject being kept between 2.8 and 8.9 degrees cooler than the
commercially available comparative shirt.
[0047] The present invention fabric provides significantly more
efficient moisture transport and evaporation, keeping the skin
drier and therefore keeping the subject cooler.
[0048] Obviously, numerous modifications and variations of the
present invention are possible in light of the above teachings. It
is therefore to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described herein.
* * * * *