U.S. patent application number 09/878416 was filed with the patent office on 2001-11-08 for durable, comfortable, air-permeable allergen-barrier fabrics.
This patent application is currently assigned to Precision Fabrics Group, Inc.. Invention is credited to Duckett, Charles Woody, Smith, John Martin III.
Application Number | 20010039157 09/878416 |
Document ID | / |
Family ID | 24678909 |
Filed Date | 2001-11-08 |
United States Patent
Application |
20010039157 |
Kind Code |
A1 |
Smith, John Martin III ; et
al. |
November 8, 2001 |
Durable, comfortable, air-permeable allergen-barrier fabrics
Abstract
An allergen-barrier fabric includes a tightly-constructed fabric
substrate, woven from 0 to 45% continuous synthetic filament yarns
and 55 to 100% natural or synthetic spun yarns. The fabric
substrate is finished to produce a fabric with a mean pore size of
4 to 10 microns, an air permeability of 0.5-25 cfm, a mean fabric
flexibility of 0.5 to 6.5 grams (bending resistance), and a
moisture vapor permeability in excess of 800 g/m.sup.2/24 hours.
This fabric provides a barrier to mite-induced allergen particles.
Various additional finishes can be included on the fabric. For
example, an antimicrobial finish may be provided on the fabric to
extend fabric wearlife by providing protection against mold and
mildew. As another alternative, a fluorochemical finish can be
provided to extend fabric wearlife by providing protection against
fluid stains.
Inventors: |
Smith, John Martin III;
(Greensboro, NC) ; Duckett, Charles Woody;
(Kernersville, NC) |
Correspondence
Address: |
FINNEGAN, HENDERSON, FARABOW, GARRETT &
DUNNER LLP
1300 I STREET, NW
WASHINGTON
DC
20005
US
|
Assignee: |
Precision Fabrics Group,
Inc.,
|
Family ID: |
24678909 |
Appl. No.: |
09/878416 |
Filed: |
June 12, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09878416 |
Jun 12, 2001 |
|
|
|
09667614 |
Sep 22, 2000 |
|
|
|
6277770 |
|
|
|
|
09667614 |
Sep 22, 2000 |
|
|
|
09165287 |
Oct 2, 1998 |
|
|
|
60061431 |
Oct 8, 1997 |
|
|
|
Current U.S.
Class: |
442/190 |
Current CPC
Class: |
A47C 27/007 20130101;
Y10T 428/249979 20150401; D03D 15/49 20210101; Y10T 442/313
20150401; D10B 2503/06 20130101; Y10T 442/2525 20150401; D06C 27/00
20130101; D10B 2401/063 20130101; D03D 15/217 20210101; A47C 27/006
20130101; D10B 2401/13 20130101; Y10T 442/2287 20150401; D06M
2200/12 20130101; D10B 2401/10 20130101; Y10T 442/3073 20150401;
Y10T 428/249978 20150401; D10B 2331/02 20130101; A47C 31/007
20130101; Y10T 442/2533 20150401; Y10T 442/3081 20150401; D10B
2331/04 20130101; Y10T 442/30 20150401; D10B 2201/02 20130101; Y10T
442/2279 20150401; D03D 15/283 20210101 |
Class at
Publication: |
442/190 |
International
Class: |
D03D 015/00 |
Claims
We claim:
1. An allergen-barrier fabric comprising: a fabric substrate, woven
from 0 to 45% continuous synthetic filament yarns and 55 to 100%
natural or synthetic yarns, finished to produce a fabric with a
mean pore size of 4 to 10-microns, an air permeability of 0.5-25
cfm, a mean fabric flexibility of 0.5 to 6.5 grams, and a moisture
vapor permeability in excess of 800 g/m.sup.2/24 hours, wherein the
fabric provides a barrier to mite-induced allergen particles.
2. The allergen-barrier fabric according to claim 1, wherein the
fabric has a maximum pore size of 10 microns.
3. The allergen-barrier fabric according to claim 1, further
comprising an antimicrobial finish on the fabric, wherein the
finish provides protection against mold and mildew.
4. The allergen-barrier fabric according to claim 1, further
comprising a fluorochemical finish on the fabric, wherein the
finish provides protection against fluid stains.
5. The allergen-barrier fabric according to claim 1, wherein the
fabric is in the form of a pillow ticking or mattress ticking.
6. The allergen-barrier fabric according to claim 1, wherein the
fabric is in the form of a pillow cover, mattress cover, mattress
pad, bedspread or duvet cover.
7. A method for providing an allergen-barrier for a pillow,
comprising: p1 covering the pillow with a non-coated, non-laminated
fabric, wherein the fabric is woven from 0 to 45% continuous
synthetic filament yarns and 55 to 100% natural or synthetic spun
yarns and finished to a fabric with a mean pore size of 4 to 10
microns, an air permeability of 0.5-25 cfm, a mean fabric
flexibility of 0.5 to 6.5 grams, and a moisture vapor permeability
in excess of 800 g/m.sup.2/24 hours, wherein the fabric provides a
barrier to mite-induced allergen particles.
8. The method according to claim 7, wherein the fabric has a
maximum pore size of 10 microns.
9. The method according to claim 7, wherein the fabric further
includes an antimicrobial finish to provide protection against mold
and mildew.
10. The method according to 7 wherein the fabric further includes a
fluorochemical finish to provide protection against fluid
stains.
11. A method according to claim 7, wherein the fabric is used as a
pillow ticking .
12. A method according to claim 7, wherein the fabric is used in a
pillow cover.
13. A method for providing an allergen-barrier for a mattress,
comprising: covering the mattress with a non-coated, non-laminated
fabric, wherein the fabric is woven from 65-100% continuous
synthetic filament yarns and finished to a fabric with a mean pore
size of 4 to 10 microns, an air permeability of 0.5-25 cfm, a mean
fabric flexibility of 0.5 to 6.5 grams, and a moisture vapor
permeability in excess of 800 g/m.sup.2/24 hours, wherein the
fabric provides a barrier to mite-induced allergen particles.
14. The method according to claim 13, wherein the fabric has a
maximum pore size of 10 microns.
15. The method according to claim 13, wherein the fabric further
includes an antimicrobial finish to provide protection against mold
and mildew.
16. The method according to claim 13, wherein the fabric further
includes a fluorochemical finish to provide protection against
fluid stains.
17. The method according to claim 13, wherein the fabric is used as
a mattress ticking, mattress cover, mattress pad, bedspread or
duvet cover.
18. The allergen-barrier fabric according to claim 1, wherein the
fabric substrate is woven from 55-65% spun polyester and 35-45%
filament polyester by weight.
19. The allergen-barrier fabric according to claim 1, wherein the
fabric substrate is woven from 55-65% spun cotton and 35-45%
filament polyester by weight.
20. The allergen-barrier fabric according to claim 1, wherein the
fabric substrate is woven from 100% spun cotton.
21. The method according to claim 7, wherein the fabric is woven
from 55-65% spun polyester and 35-45% filament polyester by
weight.
22. The method according to claim 7, wherein the fabric substrate
is woven from 55-65% spun polyester and 35-45% filament polyester
by weight.
23. The method according to claim 7, wherein the fabric substrate
is woven from 100% spun cotton.
Description
[0001] This is a continuation-in-part of application Ser. No.
09/165,287, filed Oct. 2, 1998.
FIELD OF THE INVENTION
[0002] This invention relates to allergen-barrier fabrics that are
durable, air-permeable, and comfortable. The fabrics according to
this invention have improved softness and feel while still
providing an allergen barrier that substantially impedes and/or
stops passage of dust, dust mites, and other allergens through the
fabric.
BACKGROUND OF THE INVENTION
[0003] A major source of indoor allergy-causing proteins are dust
mites. Dust mites, 100 to 300 microns in size, cannot be seen with
the naked eye. Dust mite excrement, which is a key component that
causes allergic reactions, is even smaller, ranging in size down to
10 microns. Thus, in order to be an effective barrier to dust, dust
mites, and their allergy-causing particles, a fabric or material
must limit the transmission of 10 micron particles through its
planar surface. These facts are discussed, for example, in
Platts-Mills TAE, et al., "Dust Mite Allergens and Asthma: Report
of a Second International Workshop," J. Allergy Clin. Immunology,
1992, Vol. 89, pp. 1046-1060 ("Several studies have demonstrated
that the bulk of airborne group I mite allergen is associated with
the relatively 'large' fecal particle, 10 to 40 Vm in diameter.");
AllerGuard Pte Ltd. Website, 1996 ("The house dust mite cannot be
seen with the naked eye, as it only measures 0.1 to 0.5 mm"[which
corresponds to 100 to 500 microns]); and U.S. Pat. No. 5,050,256 to
Woodcock, et al., (e.g., column 1, lines 44-46- "Ideally, if the
mite barrier has pores, it should have a pore size generally less
than 10 microns. It is apparent that anything smaller causes no
allergic reaction."). The Platts-Mills and Woodcock documents each
are entirely incorporated herein by reference.
[0004] The major concentration of dust mites in the home is found
in the bedroom. For example, an average mattress can support a
colony of 2 million dust mites. Pillows also are an excellent
habitat for dust mites. Six-year old pillows typically have 25% of
their weight made up of dust, dust mites, and allergen. Sofa
cushions, chair cushions, carpets, and other foam or fiber filled
articles also provide a suitable habitat for dust mites. In effect,
every home contains many areas where dust mites can thrive.
[0005] Additionally, the presence of allergens from dust mites is a
problem that increases as pillows, mattresses, and the like become
older. During its lifetime, a typical dust mite produces up to 200
times its net body weight in excrement. This excrement contains the
allergen that triggers asthma attacks and allergic reactions,
including congestion, red eyes, sneezing, and headaches. The
problem is exacerbated by the fact that it is difficult to remove
dust mites from the materials in which they thrive. Pillows are
rarely laundered, while most mattresses are never washed.
[0006] Commercially-available allergy-relief bedding products offer
a wide array of claims regarding their efficacy as allergen
barriers. These products are assumed to function as allergen
barriers because they form an impervious film (as with the
laminates) or because they are "tightly woven" (as with 300-count
cotton sheeting) or because they have a pore size that is too small
to permit allergen penetration (as with nonwovens).
[0007] Each of the above-noted products, however, has its own
associated disadvantages. Laminated or coated materials typically
are uncomfortable (due to little or no moisture vapor
permeability), stiff, not soft to the touch, and noisy (i.e., make
relatively loud, rustling noises when a person moves on the sheet
or pillow). Additionally, while vinyl, polyurethane, and
microporous coated fabrics are considered excellent barriers to
allergens, they require venting when used as pillow or mattress
tickings since air flow is not possible through these materials.
U.S. Pat. No. 5,050,256 describes such a product. Pillows or
mattresses covered with these materials cannot deflate and
re-inflate when compressed, unless they are vented. The need to
vent these fabrics, however, begs the question of whether they can
be considered effective allergen barriers (as allergens can also
enter and escape through the vents). Coated and laminated fabrics
also tend to have a limited wearlife due to coating
delamination.
[0008] Uncoated cotton sheetings, although promoted as such, are
not true barriers to allergens due to their inherently large pore
sizes. Allergy specialists routinely urge patients to launder their
bedding products on a weekly basis. Such practices, however, only
serve to further enlarge the pore size of cotton sheetings as fiber
is lost with extended laundering.
[0009] Spunbond/meltblown/spunbond (SMS) polyolefin nonwovens used
in mattress and pillow covers do provide a degree of barrier
protection to allergens. SMS nonwovens also exhibit excellent air
porosity. Their wearlife, however, is very short, particularly with
hot laundering temperatures normally used by allergy sufferers. SMS
nonwoven fabrics also have a significantly stiffer and harsher hand
as compared with standard pillow tickings.
[0010] Other barrier products are known from the literature and are
available on the market. For example, U.S. Pat. No. 4,822,667
issued to Goad et al. describes a reusable, launderable,
sterilizable medical barrier fabric woven from 100% polyester fiber
constructed of polyester yarn. This fabric is said to be blood and
aqueous fluid transmission resistant, abrasion resistant, flame
resistant, lint free, drapable, and sufficiently porous to
eliminate heat build-up. The described material is used in medical
garments, wraps, and sterilizable articles. This patent does not
describe the use of the fabric as an allergen barrier. The Goad
patent is entirely incorporated herein by reference.
[0011] U.S. Pat. No. 5,050,256 issued to Woodcock describes an
allergen proof bedding system with a cover permeable to water
vapor. As noted above, this patent is entirely incorporated herein
by reference. The cover material described in this patent is made
of Baxenden Witcoflex 971/973 type polyurethane-coated woven
polyester or nylon fabric. This fabric is not air permeable;
however, it does have a moisture vapor transmission ("MVT") rate of
2,500 to 7,000 g of water/m.sup.2/day. Typically, the coated side
of the fabric is on the inside of the sewn cover, and the seams are
sealed. This product, however, has the disadvantages of coated or
laminated materials described above.
[0012] U.S. Pat. No. 5,368,920 issued to Schortmann (International
Paper Co.) describes a nonporous, breathable barrier fabric and
related methods of manufacture. The fabric is a breathable barrier
fabric created by filling void spaces in a fabric substrate with
film-forming clay-latex material having a density range of 1,000 to
2,000 gm/I, to provide a barrier fabric permeable to water vapor
and impermeable to liquids and air. The MVT rate ranges from 300 to
3,000 g/m.sup.2/day. Applications include industrial, hospital, and
other protective coverings. Again, this product has the
disadvantages associated with coated and laminated fabrics, as
described above.
[0013] Dancey, in U.S. Pat. No. 5,321,861, describes a protective
cover for upholstered or padded articles, such as bedding, made
from a microporous ultrafilter material having a pore size of less
than 0.0005 mm. This material suppresses passage of fecal particles
produced by house dust mites. To prevent particles from bypassing
the ultrafilter material, the seams of the cover are welded, and
its opening is sealed by a resealable fastener, such as a
zip-fastener, covered with an adhesive tape.
SUMMARY OF THE INVENTION
[0014] It is an object of this invention to overcome the various
disadvantages of the known allergen and barrier fabric materials
and to provide a fabric that is soft and comfortable, but still
provides an effective barrier against transmission of dust, dust
mites, their excrement, and other allergens.
[0015] According to this invention, an allergen-barrier fabric
includes a tightly-constructed fabric substrate, woven from
continuous natural and/or synthetic filament and/or spun yarns. The
fabric substrate is finished so as to provide a fabric with a mean
pore size of 4 to 10 microns, an air permeability of 0.5-25 cubic
feet per minute per square foot of fabric at 0.5 inches of water
("cfm," measured by Federal Test Method Standard (FTM) 5450, also
known as ASTM D-737), a mean fabric flexibility of 0.5 to 6.5 grams
(bending resistance), and a moisture vapor permeability in excess
of 800 g/m.sup.2/24 hours. These specifications relate to the
finished fabric, prior to regular use and laundering. With these
specifications, the resultant fabric is soft and comfortable while
still providing a barrier to mite-induced allergen particles.
[0016] In a preferred embodiment of the invention, the
allergen-barrier fabric has a maximum initial pore size of 10
microns.
[0017] Various fabric finishes can be included on the
allergen-barrier fabric of the invention. For example, the
allergen-barrier fabric can include an antimicrobial finish to
extend fabric wearlife by providing protection against mold and
mildew. As another example, the allergen-barrier fabric of the
invention also can include a fluorochemical finish to extend fabric
wearlife by providing protection against fluid stains. These
additional finishes can be used individually, in combination, or
together with other possible finishes.
[0018] This invention further relates to a method for providing an
allergen-barrier for a pillow or mattress by covering the pillow or
mattress with a tightly-constructed, non-coated, non-laminated
fabric. The fabric, as noted above, is woven from continuous
natural and/or synthetic filament and/or yarns and finished to a
fabric with a mean pore size of 4 to 10 microns, an air
permeability of 0.5-25 cfm, a mean fabric flexibility of 0.5 to 6.5
grams (bending resistance), and a moisture vapor permeability in
excess of 800 g/m.sup.2/24 hours. This fabric provides a barrier to
mite-induced allergen particles.
[0019] In this invention, the allergen-barrier cover material can
take on any suitable form. For example, it can be a pillow ticking,
a pillow cover, a mattress ticking, a mattress cover, a mattress
pad, a duvet cover, or a bedspread. Furthermore, while it is
preferred that the allergen-barrier fabric according to the
invention cover all surfaces of the pillow or mattresses so as to
completely encase the pillow or mattress, this is not a requirement
in all embodiments. For example, typical mattress pads do not
completely encase a mattress.
DETAILED DESCRIPTION OF THE INVENTION
[0020] This invention relates to an allergen-barrier fabric that
possesses a unique combination of properties to provide an
allergen-barrier material that is superior to other commercially
available products. The fabric according to the invention has a
unique combination of air porosity (to allow venting through the
fabric's planar surface), moisture vapor transport (to enhance a
user's comfort), fabric flexibility (also a comfort-enhancing
property), extremely small pore size (to filter out allergens), and
durability to laundering (as required of allergy-relief products)
to provide that superior product. This combination of properties is
provided by weaving fine-denier synthetic filament yarns into a
tight plain-weave construction with post finishing processes that
maximize fiber coverage and filtration efficiency. In effect, the
fabrics according to the invention provide the barrier performance
of coated or laminated fabrics, while exhibiting the flexibility,
air porosity, and moisture-vapor porosity needed to enhance comfort
and "refluffability" of fiber-filled products, and while also
offering a durability not possible with nonwoven or
coated/laminated fabrics.
[0021] The fabric material according to the invention can be used
for any suitable purpose, but it is preferably used as a fabric for
covering items that typically are susceptible to dust mite
infestation. As noted above, pillows and mattresses provide a very
favorable environment for sustaining dust mite colonies. Therefore,
advantageously, the fabric according to the invention can be used
for pillow tickings, pillow covers, mattress pads, mattress
tickings, mattress covers, duvet covers, and/or bedspreads. When
used in such articles, the fabric provides a barrier to prevent
dust mites from entering, a pillow or mattress. Additionally, the
fabric, when used in such articles, can prevent dust mites and
allergens already existing in mattresses and pillows from exiting
the mattress or pillow e.g., when the article is compressed during
use.
[0022] As used in this patent application, the following
definitions apply:
[0023] A "pillow ticking" means a pillow's non-removable fabric
covering that encases the fiberfill or other padding.
[0024] A "pillow cover" means a pillow's removable fabric cover
that also can function as a decorative, washable encasement (e.g.,
a pillow case). For allergy sufferers, a pillow cover also can
function as an allergen barrier. Pillow-cover closures are usually
either zippers or overlapping flaps.
[0025] A "mattress pad" is a quilted removable covering for a
mattress. For allergy sufferers, the innermost or the outermost
fabric in the pad can function as an allergen barrier.
[0026] A "mattress ticking" means a mattress's non-removable fabric
covering that encases the fiberfill or other padding and
springs.
[0027] A "mattress cover" is a mattress's removable fabric cover
that also can function as a decorative, washable encasement.
Institutional mattress covers also must provide a barrier to
fluids. For allergy sufferers, such a cover also can function as an
allergen barrier. Mattress-cover closures typically are either
zippers or overlapping flaps.
[0028] Given the above background information, the invention will
now be described in more detail. This invention embodies a textile
system that can advantageously be used as an integral component in
pillow covers, pillow cases, pillow tickings, mattress cases,
mattress pads, mattress tickings, mattress covers, duvet covers,
and bedspreads for the purpose of creating a barrier to
mite-induced allergen particles. The invention is not limited,
however, to these enumerated products. For example, the fabric
according to the invention could be used in many other products,
such as sheets, sleeping bags, down-filled bedding, upholstered
furniture, stuffed toys, and similar fiber-filled or padded
items.
[0029] The textile system according to the invention is comprised
of natural and/or synthetic spun and/or filament yarns of polyester
and/or nylon and/or cotton, closely woven, and subsequently
scoured, heat-treated, or otherwise finished to further constrict
the fabric's pore size. The textile fabric's construction and
chemical treatments are controlled to impart a unique combination
of:
[0030] (1) air permeability (to provide compressibility necessary
when used in covers for fiber-filled bedding products);
[0031] (2) moisture vapor permeability (to enhance sleeping
comfort);
[0032] (3) fabric flexibility (also to enhance comfort);
[0033] (4) laundering durability (to provide relatively long term
allergen-barrier protection after several wash cycles as typically
required for allergy-relief textile articles);
[0034] and
[0035] (5) filtration efficiency (the paramount feature necessary
to function as a barrier to allergens). The fabric according to
this invention provides an excellent combination of these five
textile properties to produce a barrier fabric that is superior to
other commercially-available materials.
[0036] Preferred embodiments of this invention include a fabric
substrate made from 55-65% spun polyester and 35-45% filament
polyester, 55-65% spun cotton and 35-45% filament polyester, and
100% spun cotton all by weight, densely woven in a plain weave,
with warp and filling yarns totaling 215 yarns per square inch. The
preferred fabric finishing process includes scouring, heat setting,
width/length fabric shrinkage, and mechanical manipulation to
further compact the yarn-to-yarn spacing. The resulting fabric
product has a mean pore size of 4 to 10 microns, an air
permeability of 0.5-25 cfm (advantageously, 0.5 to 15 cfm), a mean
fabric flexibility of 0.5 to 6.5 grams (bending resistance), and a
moisture vapor permeability in excess of 800 g/m.sup.2/24 hours
(advantageously 1100 to 2400 g/m.sup.2/24 hours or 1200 to 2400
g/m.sup.2/24 hours). Mechanical manipulation can involve
calendaring, wherein yarns are flattened via heat and pressure to
further close fabric pores; dimensional shrinkage, wherein fabrics
are bulked and agitated in conventional pressure jet equipment in
such a way as to cause width and/or length shrinkage of the fabric
to its minimum yarn spacing, or high-speed impingement and
agitation via water or dye liquor, wherein fibers are flattened and
dispersed in a highly uniform manner. No further coatings or film
laminations are required.
[0037] As mentioned above, during production of the fabric
according to the invention, high pressure water or dye liquor can
be sprayed onto the surface of the fabric. This process tends to
matt out the fabric fibers, thereby reducing the spaces between
fibers and the fabric pore size and also improving the fabric
softness and hand. This high pressure liquid impingement process
also can be used to texturize or pattern the fabric, if desired.
Suitable devices and systems for performing this high pressure
liquid impingement are described, for example, in U.S. Pat. Nos.
4,967,456; 4,995,151; and 5,632,072, each of which is entirely
incorporated herein by reference.
[0038] Chemical enhancements to the preferred embodiment of the
fabric according to the invention include the application of a
permanent antimicrobial finish and a flexible fluorochemical
finish. In this context, "permanent" denotes efficacy of the
respective finishes for the lifetime of the product. Any suitable
antimicrobial or fluorochemical finish can be used without
departing from this invention, and such finishes are known in the
art (see, for example, U.S. Pat. No. 4,822,667, supra.). As an
example of a suitable antimicrobial finish, a very durable compound
of 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride
(Dow Coming 5700) can be applied. This finish protects the fabric
against bacteria and fungi, and inhibits the growth of odor-causing
bacteria. It has-been shown to be effective against bacteria
(Streptococcus faecalis, K. pneumoniae), fungus (Aspergillus
niger), yeast (Saccharomyces cerevisiae), wound isolates
(Citrobacter diversus, Staphylococcus aureus, Proteus mirabilis),
and urine isolates (Pseudomonas aeruginosa, E. coli). The
fluorochemical finish can be a permanent micro-thin flexible
fluorochemical film that imparts fluid repellency (see, for
example, those described in U.S. Pat. No. 4,822,667, supra.).
Unlike fabrics used in medical barrier applications, however, the
allergy barrier fabric according to the present invention is
generally not concerned with fluid repellency properties, as
exemplified by a substantially negligible Suter rating. A Suter
rating is an indication of a fabric's resistance to water
penetration, as measured by a hydrostatic pressure test,
specifically, the hydrostatic head required for three drops of
water to penetrate a fabric. The lower the Suter rating, the lower
the fabric's resistance to water penetration, i.e., the lower the
hydrostatic head required for three drops of water to penetrate a
fabric. In the case of the claimed fabric, the Suter rating is
below 20.
[0039] The use of polyester and/or nylon and/or cotton of
continuous filament and/or spun yarns in the fabric according to
the invention creates a high-strength, flexible substrate that is
extremely durable to home and commercial laundering. Subsequent
fluorochemical and antimicrobial finishes, as described above,
further protect the fabric against degradation due to fluid stains,
molds, and mildew. Because the fabrics are tightly woven where
yarn-to-yarn abrasion is restricted, there is little chance for
fiber breakage and linting. Therefore, fabric pore sizes remain
sufficiently and consistently small throughout extended laundering.
This is important because if excessive fiber is lost during actual
use or through extended launderings, progressively larger pore
sizes are created and the allergen-barrier properties of the fabric
product would be significantly deteriorated.
[0040] Fiber-filled products using the fabrics according to the
invention as a covering material can be compressed and then recover
without the loss of allergen-barrier properties. Air vents are not
required as an integral component of the fabricated product, thus
reducing labor and material costs associated with its manufacture.
The lack of air vents also eliminates potential entry/exit ports
for dust mites and associated allergens.
[0041] The flexibility of the fabrics according to the invention
has a very positive effect upon the drape, noise, handle, and
comfort of the ultimate end-item. The inventive fabrics have a mean
fabric flexibility of 0.5 to 6.5 grains (bending resistance). The
mean flexibility is the mean of the bending resistance of the
fabric in the machine direction (MD) and the cross machine
direction (XD), measured by INDA Test No. IST-90.3 on a
Handle-O-Meter Model 211-5. Because the fabrics according to the
invention do not involve coatings or laminations, their flexibility
and ease of movement is excellent.
[0042] The fabrics according to the invention also have a moisture
vapor permeability or transmission rate in excess of 800
g/m.sup.2/24 hours. In certain embodiments of the invention, the
moisture vapor permeability is in the range of 1100 to 2400
g/m.sup.2/24 hours, and advantageously between 1200 and 2400
g/m.sup.2/24 hours. By maintaining a moisture vapor permeability of
at least 800 g/m.sup.2/24 hours, comfort levels for the user are
enhanced because the passage of evaporating perspiration through
the material is not impaired. This feature is a decided advantage
over vinyl-coated products.
[0043] Furthermore, given that the fabrics according to the
invention are not coated or laminated, coating loss or delamination
during use or laundering (which leads to barrier performance
degradation) is not possible. This is another advantage of the
invention over coated or laminated products. The useful life of
bedding articles fabricated from the fabrics according to the
invention is thereby maximized.
[0044] Finally, by maintaining a mean pore size of 4 to 10 microns,
the fabrics according to the invention are very effective barriers
to dust mites and their allergy-causing excrement. In another
embodiment of this invention, the fabric has a maximum pore size of
10 microns. This small maximum pore size provides long term
protection against dust, dust mite, and allergen transmission.
[0045] Specific examples of fabric products according to the
invention follows. As with the more general description above,
these examples should be construed as illustrating the invention
and not as limiting the same.
EXAMPLES
[0046] This invention, as described above, includes a unique and
unequaled combination of durability, flexibility, air porosity,
moisture vapor transport, and allergen-barrier performance as
compared with existing bedding cover fabrics.
Example 1
[0047] A suitable fabric according to the invention was
manufactured from 70-denier, 34-filament texturized polyester
yarns, woven in a plain-weave construction. After weaving, the
fabric construction had 129 warp ends per inch and 86 filling yarns
per inch, with a fabric weight of 2.28 ounces per yard. Subsequent
processes included scouring, calendaring, and treating with durable
antimicrobial and fluorochemical finishes. After processing, the
fabric construction was 144 warp ends per inch and 89 filling yarns
per inch, with a fabric weight of 2.56 ounces per yard.
[0048] Comfort and barrier properties for this fabric are given in
the Table below:
1 TABLE I Original After Five Launderings Pore Size Minimum 2.060
.mu. 2.731 .mu. Maximum 9.935 .mu. 12.85 .mu. Mean 4.372 .mu. 5.156
.mu. Moisture Vapor 1,207 g/m.sup.2/24 hours 1,265 g/m.sup.2/24
hours Transmission Rate Flexibility * 6.1 grams 3.2 grams Air
Permeability 0.622 cubic feet/minute 1.130 cubic feet/minute *
Measured as the mean bending resistance (grams of resistance to
bending) of the fabric in the machine direction (MD) and the cross
machine direction (XD) using INDA Test No. IST-90.3, Handle-O-Meter
Model 211-5.
Example 2
[0049] A suitable fabric according to the invention was
manufactured from 40/1 Ring Spun Combed Cotton, woven in a plain
weave construction. After weaving, the fabric construction had 112
warp ends per inch and 124 filling yarns per inch, with a fabric
weight of 4.40 ounces per square yard. Subsequent processes include
scouring, relax drying, and calendaring. After processing, the
fabric construction was 120 warp ends per inch and 120 filling
yarns per inch, with a fabric weight of 4.25 ounces per square
yard.
[0050] Comfort and barrier properties for this fabric are given in
the Table below.
2 TABLE 2 Original After Five Launderings Pore Size Minimum 4.170
.mu. 3.809 .mu. Maximum 15.855 .mu. 16.202 .mu. Mean 4.558 .mu.
5.014 .mu. Moisture Vapor 806 g/m.sup.2/24 hours 965 g/m.sup.2/24
hours Transmission Rate Flexibility * 9.9 grams 4.1 grams Air 3.50
cubic feet/minute 6.82 cubic feet/minute Permeability * Measured as
the mean bending resistance (grams of resistance to bending) of the
fabric in the machine direction (MD) and the cross machine
direction (XD) using INDA Test No. IST-90.3, Handle-O-Meter Model
211-5.
Example 3
[0051] A suitable fabric according to the invention was
manufactured from 70 denier, 34 filament texturized polyester yarn
in the warp direction, and 26/1 Air Jet Spun Polyester in the
filling direction, woven in a plain weave construction. After
weaving, the fabric construction had 144 warp ends per inch and 78
filling yarns per inch, with a fabric weight of 3.73 ounces per
square yard. Subsequent processes include scouring, and tenter
frame finishing. After processing, the fabric construction was 164
warp ends per inch and 88 filling yarns per inch, with a fabric
weight of 4.45 ounces per square yard.
[0052] Comfort and barrier properties for this fabric are given in
the Table below.
3 TABLE 3 Original After Five Launderings Pore Size Minimum 8.399
.mu. 8.046 .mu. Maximum 19.584 .mu. 19.022 .mu. Mean 8.934 .mu.
8.990 .mu. Moisture Vapor 950 g/m.sup.2/24 hours 1080 g/m.sup.2/24
hours Transmission Rate Flexibility * 5.0 grams 21.8 grams Air 7.8
cubic feet/minute 7.6 cubic feet/minute Permeability * Measured as
the mean bending resistance (grams of resistance to bending) of the
fabric in the machine direction (MD) and the cross machine
direction (XD) using INDA Test No. IST-90.3, Handle-O-Meter Model
211-5.
Example 4
[0053] A suitable fabric according to the invention was
manufactured from 70 denier, 34 filament texturized polyester yarn
in the warp direction, and 28/1 open end combed cotton spun yarn in
the filling direction, woven in a plain weave construction. After
weaving, the fabric construction had 144 warp ends per inch and 78
filling yarns per inch, with a fabric weight of 3.58 ounces per
square yard. Subsequent processes include scouring, and tenter
frame finishing. After processing, the fabric construction was 164
warp ends per inch and 88 filing yarns per inch, with a fabric
weight of 3.80 ounces per square yard.
[0054] Comfort and barrier properties for this fabric are given in
the Table below.
4 TABLE 4 Original After Five Launderings Pore Size Minimum 6.088
.mu. 6.002 .mu. Maximum 18.156 .mu. 18.640 .mu. Mean 8.992 .mu.
9.108 .mu. Moisture Vapor 961 g/m.sup.2/24 hours 992 g/m.sup.2/24
hours Transmission Rate Flexibility * 6.8 grams 4.4 grams Air 14.5
cubic feet/minute 5.8 cubic feet/minute Permeability * Measured as
the mean bending resistance (grams of resistance to bending) of the
fabric in the machine direction (MD) and the cross machine
direction (XD) using INDA Test No. IST-90.3, Handle-O-Meter Model
211-5.
[0055] In this application, Applicant has described certain
theories and/or mechanisms in an effort to explain how and why this
invention works in the manner in which it works. These theories and
mechanisms are set forth for informational purposes only. Applicant
is not to be bound by any particular chemical, physical, or
mechanical theory of operation.
[0056] While the invention has been described in terms of various
preferred embodiments using specific examples, those skilled in the
art will recognize that various changes and modifications can be
made without departing from the spirit and scope of the invention,
as defined in the appended claims.
* * * * *