Note: Descriptions are shown in the official language in which they were submitted.
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ABSORBENT, NON-PERMEABLE FABRICS AND METHOD OF DISPOSAL THEREOF
Background of the Invention
I. Field of the Invention:
The present invention relates to the field of fabrics and, particularly, to
articles
which are absorbent to liquids, yet not completely permeable to liquids.
II. Background of the Invention:
Hospital patient care generates considerable quantities of infectious medical
waste in primary and acute care facilities. Such facilities have a need to
provide
various textile products to be used by physicians and other professionals, as
well as for
bedding, draperies, towels, and similar items.
At one time, virtually all textiles used in such environments were reusable.
Reusable textiles were primarily made from woven fabrics of yarns and the
yarns were
composed of cotton or other natural fibers. However, synthetics were later
developed
which included fibers such as nylon and polyester. These synthetics were
primarily
spun from staple fibers and very little texturized synthetic filaments were in
use at that
time.
Approximately thirty years ago, disposable garments, covers, linens and drapes
were introduced to the medical environment. When compared to the reusable
garments,
the disposables offered many cost- and time-saving features. For instance,
hospitals
were able to reduce or entirely eliminate their laundry facilities and the
hospital had, for
the first time, garments that exhibited significant barrier protection. Barner
protection
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2
is important in hospitals to prevent unwanted contact of the wearer to harmful
liquids,
infections agents, and other bodily fluids.
Another significant drawback to reusable textiles was that they could not
provide liquid burner capabilities, especially after only a few laundry
cycles. However,
the average lifetime of a hospital reusable was approximately 18 laundry
cycles.
Current disposables are generally non-woven in composition. For instance,
carded stock is often chemically bonded into fabrics. Such carded webs are
treated
with adhesives or bonding agents and are then calendared to form "paper-light"
materials. Carded webs have recently been replaced by thermobond materials,
which
have a softer "hand," but which have reduced cross-directional strength.
Further current disposables are produced from air-entangled and hydroentangled
fibers which produce suitable fabrics. Such non-wovens are composed mostly of
polypropylene fibers or from a polyester staple with cellulose wood pulp.
These
hydroentangled webs display the most textile-like hand, as well as a high
degree of
dimensional or cross-directional strength. Non-wovens of this class, such as
SONTARA~ by Du Pont, are widely accepted for use in medical gowns and drapes.
Recently, the medical industry has begun reverting to the use of reusable
items.
This trend arose because the disposable items produced significant infectious
waste
products. Originally, disposables were favored because they promoted anti-
septic
patient contact and decreased the potential for cross-infections between
patients, a
significant problem with cleanable, reusable textiles. However, various
federal and
state regulations have subsequently reclassified much of the disposable
product as
"infectious," thereby making desirable the minimization of their use.
An average hospital patient produces 55 lbs. of medical waste per day.
Approximately 20 % of that waste is classified as "infectious." The American
Hospital
CA 02268345 1999-04-09
3
or splashed liquids, the liquids are quite capable of permeating the to ;tile
and thereby
recontacting the patient or the medical worker.
U.S. Patent S,207,837 discloses a method of disposing garments made ftom a
thermoplastic PVA polymer after use. U.S. Patent No. 3,809,077 discloses a
three
layer surgical drape in which a thermoplastic film is sandwiched between two
absorbent lavers~of fabric.
The invention herein solves the drawbacks of the prior art by providing a
textile
suitable for use in the medical environment, such as for use as a gown or a
drape, which
is capable of absorbing harmful liquids yet preventing contact of the liquids
with a
patient or worker. Moreover, the invention, in another embodiment, provides
such a
textile which can be disposed of without additional risk of contamination or
reinfection.
- In addition, the invention provides a textile disposal process that does not
require the
1 ~ article to be introduced to a landfill, where it would be environmentally
detrimental as
well as potentially infectious. The invention also provides an alternative
textile in
which these desirable capabilities are provided for in a unitary, i. e., one
piece, non-
laminated article.
Summary of the Invention
The present invention provides an article comprising a fabric layer permeable
to
a first liquid and having a first side and an opposed second side, wherein the
first side
of the fabric layer further comprises a coating repellent to the first liquid,
wherein the
2~ coating substantially penetrates into the fast side of the fabric_ layer,
thereby forming a
first liquid proof first side. In a further embodiment, the fabric layer is
soluble in a
second liquid when the second liquid is hot and insoluble in the second liquid
when the
second liquid is cold. In a further embodiment, the article is a surgical
fabric. In yet a
further embodiment, the article is a surgical drape. In a further embodiment,
the fabric
layer dissolves in the second liquid only at a temperature above 37 ~C.
AMEr~JLD SHEET
,e '.~.y.'. iW. I~ ~~.:~ a, i
1 '_~ r: ~--~ '...~ ,
CA 02268345 1999-04-09
3a
in an alternative embodiment, the article further comprises a plastic layer
having a first side and an opposed second side, wherein the f rst side of the
plastic layer
faces the first side of the fabric layer.
~=,f~-;;d~:.~D SHEET
f _ ,~ ~..w c f''.~. ~ a
...
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4
or splashed liquids, the liquids are quite capable of permeating the textile
and thereby
recontacting the patient or the medical worker.
The invention herein solves the drawbacks of the prior art by providing a
textile
suitable for use in the medical environment, such as for use as a gown or a
drape, which
is capable of absorbing harmful liquids yet preventing contact of the liquids
with a
patient or worker. Moreover, the invention, in another embodiment, provides
such a
textile which can be disposed of without additional risk of contamination or
reinfection.
In addition, the invention provides a textile disposal process that does not
require the
article to be introduced to a landfill, where it would be environmentally
detrimental as
well as potentially infectious. The invention also provides an alternative
textile in
which these desirable capabilities are provided for in a unitary, i. e. , one
piece, non-
laminated article.
Summary of the Invention
The present invention provides an article comprising a fabric layer permeable
to
a first liquid and having a first side and an opposed second side, wherein the
first side
of the fabric layer further comprises a coating repellent to the first liquid,
wherein the
coating substantially penetrates into the first side of the fabric layer,
thereby forming a
first liquid proof first side. In a further embodiment, the fabric layer is
soluble in a
second liquid when the second liquid is hot and insoluble in the second liquid
when the
second liquid is cold. In a further embodiment, the article is a surgical
fabric. In yet a
further embodiment, the article is a surgical drape. In a further embodiment,
the fabric
layer dissolves in the second liquid only at a temperature above 37 ~C.
In an alternative embodiment, the article further comprises a plastic layer
having
a first side and an opposed second side, wherein the first side of the plastic
layer faces
the first side of the fabric layer.
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In yet another embodiment, the present invention provides an article
comprising
a first fabric layer permeable to a first liquid and having a first side and
an opposed
second side, wherein the first side of the first fabric layer further
comprises a coating
repellent to the first liquid, wherein the coating substantially penetrates
into the first
5 side of the first fabric layer, thereby forming a first liquid proof first
side of the first
fabric layer, and a second fabric layer permeable to the first liquid and
having a first
side and an opposed second side, wherein the first side of the second fabric
layer further
comprises a coating repellent to the first liquid, wherein the coating
substantially
penetrates into the first side of the second fabric layer, thereby forming a
first liquid
proof first side of the second fabric layer, whereby the first liquid proof
first side of the
first fabric layer faces the first liquid proof first side of the second
fabric layer. In
another embodiment, the first and second fabric layers are soluble in a second
liquid
when the second liquid is hot and insoluble in the second liquid when the
second liquid
is cold. In a further embodiment, the article is a surgical fabric. In yet a
further
embodiment, the article is a surgical drape. In a further embodiment, the
fabric layer
dissolves in the second liquid only at a temperature above 37 ~C.
In a further embodiment, at least one plastic layer is disposed between the
first
liquid proof side of the first fabric layer and the first liquid proof side of
the second
fabric layer. In a further embodiment, the first and second fabric layers are
soluble in a
second liquid when the second liquid is hot and insoluble in the second liquid
when the
second liquid is cold.
In yet another embodiment, the present invention provides a method of
disposing of the articles of the invention, wherein the fabric Layer is
soluble in a second
liquid when the second liquid is hot and insoluble in the second liquid when
the second
liquid is cold, comprising contacting the article with a sufficiently hot
second liquid for
a sufficient period of time to disperse or dissolve substantially the article.
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6
Additional advantages of the invention will be set forth in part in the
description
which follows, and in part will be obvious from the description, or may be
learned by
practice of the invention. The advantages of the invention will be realized
and attained
by means of the elements and combinations particularly pointed out in the
appended
claims. It is to be understood that both the foregoing general description and
the
following detailed description are exemplary and explanatory only and are not
restrictive of the invention, as claimed.
Brief Description of the Drawings
Figure 1 shows one embodiment of the present invention.
Figure 2 shows another embodiment of the present invention.
Figure 3 shows another embodiment of the present invention.
Figure 4 shows another embodiment of the present invention.
Detailed Description of the Preferred Embodiments
The present invention may be understood more readily by reference to the
following detailed description of preferred embodiments of the invention and
the
Figures.
Before the present methods and apparatuses are disclosed and described, it is
to
be understood that the terminology used herein is for the purpose of
describing
particular embodiments only and is not intended to be limiting. It must be
noted that,
as used in the specification and the appended claims, the singular forms "a,"
"an" and
"the" include plural referents unless the context clearly dictates otherwise.
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Throughout this application, where publications are referenced, the
disclosures
of these publications in their entireties are hereby incorporated by reference
into this
application in order to more fully describe the state of the art to which this
invention
pertains.
As used herein, the term "fabric layer" refers to a woven or non-woven fabric
material suitable for producing textile-like articles. One or more layers of
the fabric
may comprise a "fabric layer".
As used herein, the term "permeable" refers to the ability of a particular
article
or item to permit fluids, such as liquids, to pass therethrough or to
penetrate therein.
As used herein, the term "liquid" refers to fluids such as water, blood, and
urine.
I S As used herein, the term "coating" refers to a distinct portion of a
surface having
the stated properties. The "coating" may be contiguous with the substrate or
may
comprise a separate layer affixed thereto.
As used herein, the term "repellent", when used in connection with a coating,
describes the ability of the coating to resist, at least partially, permeation
or penetration
by the specified fluid. Hence, a "water repellent" article resists water from
permeating
the article.
As used herein, the term "substantially penetrates" refers to the extent to
which
the stated material has integrated into the specified substrate. Substantial
penetration,
as used herein, involves a penetration into the item of from about 10 to about
90 %,
more preferably 20 to 80 %, most preferably about 50 % of the thickness of the
item.
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As used herein, the term "dispersable" refers to an item which may or may not
dissolve completely in the stated fluid, such as a liquid, but does
structurally fragment
or break apart in the presence of the fluid.
As used herein, the term "hot" is used to refer to temperatures above about
body
temperature, or 37 ~C. More preferably, "hot" refers to temperatures above 40
~C, more
preferably to temperatures above 45 ~C, even more preferably to temperatures
above 50
~C, even more preferably to temperatures above 75 ~C, and most preferably to
temperatures above 90 ~C. Similarly, "cold" is used to refer to temperatures
below
about body temperature, or 37 ~C. More preferably, "cold" refers to
temperatures
below 30 ~C, more preferably to temperatures below 25 ~C, and even more
preferably
to temperatures below 20 ~C.
As used herein, the term "surgical fabric" refers to a textile like woven or
non-
woven article suitable for use in an operating room. Such fabrics include, but
are not
limited to gowns, drapes, and masks. Thus, a "surgical drape" is one type of
"surgical
fabric."
As used herein, especially with respect to drapes, the term "operating
aperture"
refers to an opening cut through one of the articles of the invention so as to
permit a
surgical or other procedure to be performed through the opening.
As used herein with respect to various layers of the article, the terms
"face",
"facing" and "faces" refer to two or more layers that are positioned adjacent
to one
another with the indicated sides directed toward one another. Facing layers
need not be
in contact and may, optionally, have further matter disposed therebetween.
As used herein, the term "laminated" refers to the process of producing an
article by accumulating layers of specified materials.
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As used herein, the term "adhered" refers to temporary or permanent affixation
of the specified items. Adherence may occur with or without additional
materials such
as adhesives. Suitable adhesives, where used, include glues and the like.
The present invention therefore provides, in one embodiment, an article
comprising a fabric layer permeable to a first liquid and having a first side
and an
opposed second side, wherein the first side of the fabric layer further
comprises a
coating repellent to the first liquid, wherein the coating substantially
penetrates into the
first side of the fabric layer, thereby forming a first liquid proof first
side.
In an alternative embodiment, the fluid impermeability of the article is
further
ensured by providing a plastic layer having a first side and an opposed second
side.
The plastic layer is oriented with respect to the fabric layer such that the
first side of the
plastic layer faces the first side of the fabric layer. In one embodiment, the
plastic layer
comprises any polymer having a melting temperature below 100 ~C. Suitable
polymers
include, but are not limited to, polycaprolactone or polyvinyl) alcohol.
Moreover, the
polymer is preferably biodegradable, but non-biodegradable polymers are also
suitable.
Such non-biodegradable polymers include, but are not limited to, polyethylene
and
polyolefin copolymer, polyethylene and polymethylacrylate copolymer, and
polyethylene polyesters.
In still a further embodiment, the fabric layer and the plastic layer are
laminated.
Alternatively, the fabric layer and the plastic layer may adhered together
with an
adhesive. One of ordinary skill in the art would recognize that there are
numerous
suitable adhesives that could be used, such as, but not limited to, a glue.
In yet another embodiment, the present invention provides an article
comprising
a first fabric layer permeable to a first liquid and having a first side and
an opposed
second side. The first side of the first fabric layer is further coated with a
coating
repellent to the first liquid. Preferably, the coating substantially
penetrates into the first
CA 02268345 1999-04-09
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side of the first fabric layer. The coated, penetrated first fabric layer
thereby forms a
first liquid proof first side of the first fabric layer. In addition, the
article also
comprises a second fabric layer permeable to the first liquid and having a
first side and
an opposed second side. The first side of the second fabric layer also has a
coating
5 repellent to the first liquid placed thereon. This coating also
substantially penetrates
into the first side of the second fabric layer and forms a first liquid proof
first side of
the second fabric layer. The article is formed such that the first liquid
proof first side of
the first fabric layer faces the first liquid proof first side of the second
fabric layer. In
the fashion a particularly preferable article is formed such that the article
can absorb
10 contaminants emanating from the environment and from the patient or wearer,
yet the
article is capable of preventing the contaminants from passing through the
article and
becoming a further hazard.
In a preferred embodiment, the first and second fabric layers are soluble in a
second liquid when the second liquid is hot and insoluble in the second liquid
when the
second liquid is cold. In a preferred embodiment, the first liquid is water.
In another
preferred embodiment, the second liquid is water. In one embodiment, the
article is a
surgical fabric, such as a surgical drape. In another embodiment, the fabric
layer of the
drape has a portion cut therefrom, thereby defining an operating aperture of
the drape.
In yet another embodiment, the article also has at least one plastic layer
disposed between the first liquid proof side of the first fabric layer and the
first liquid
proof side of the second fabric layer. Thus, the plastic layer may be
comprised of a
single layer of plastic, or, alternatively, may be comprised of two or more
plastic layers
adj acent to one another. For instance, the article could be made from two of
the articles
of Figure 1, joined at their plastic layer sides. The "total thickness" of the
at least one
plastic layer refers to the cumulative thickness of all of the plastic layers.
The plastic
layer is preferably of from 1 to 2 mils in thickness. This article provides an
enhanced
fluid barrier between the first and second sides of the article. In a
preferred
embodiment, the at least one plastic layer is adhered to both the first liquid
proof side of
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As noted above, because of the desirability of disposing of the articles,
preferred
articles include surgical fabrics and surgical drapes. For surgical drapes,
the fabric
layer of the drape can, optionally, have a portion cut therefrom. This opening
defines
an operating aperture on the drape.
In further embodiments of the articles, the fabric layer has a density of from
20
to about 120 a%rri2, more preferably of from 40 to about 100 g/m'', even more
preferably
from about 60 to about 80 g/m', and most preferably about ?0 g/m''. In yet
another
embodiment, the fabric layer has a thickness of from about 0.02 mils to about
60 mils.
In yet other embodiments, the fabric layer dissolves in the second liquid only
at
a temperature above 37 ~C, more preferably only at a temperature above 40 ~C,
still
more preferably only at a temperature above 45 ~C, even more preferably only
at a
temperature above ~0 ~C, even more preferably only at a temperature above 7~
~C, and
most preferably only at a temperature above 90 ~C.
In one embodiment, the fabric comprises polyvinyl) alcohol. In a preferred
embodiment, the polyvinyl) alcohol is a greater than 9~% saponified poly vinyl
acetate, more preferably greater than 98% saponified poly vinyl acetate, even
more
preferably greater than 99% saponified poly vinyl acetate, and even more
preferably is
greater than 99.99% saponified poly vinyl acetate. The fabric layer is an
absorbent
material so that the liquid can be absorbed quickly without spillage onto the
patient's
body. Suitable hot liquid soluble, cold liquid insoluble materials, such as
poly vinyl
alcohol materials, are described in detail in U.S. Patents No. a181,966, ~,1 S
1,967, and
2~ 5,207,837. Other suitable materials for forming the fabric have been listed
above with
respect to the plastic layer.
In addition to these articles, the present invention also provides a disposal
method applicable to the articles. In particular, the present invention
pro~~ides a method
_ ' ;.',~~a~v S~cEj
1 ~z..= ~ a ;r:.,;."~ ~-:.:
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12
As noted above, because of the desirability of disposing of the articles,
preferred
articles include surgical fabrics and surgical drapes. For surgical drapes,
the fabric
layer of the drape can, optionally, have a portion cut therefrom. This opening
defines
an operating aperture on the drape.
In further embodiments of the articles, the fabric layer has a density of from
20
to about 120 glmz, more preferably of from 40 to about 100 g/m2, even more
preferably
from about 60 to about 80 g/mz, and most preferably about 70 g/m2. In yet
another
embodiment, the fabric layer has a thickness of from about 0.02 mils to about
60 mils.
In yet other embodiments, the fabric layer dissolves in the second liquid only
at
a temperature above 37 ~C, more preferably only at a temperature above 40 ~C,
still
more preferably only at a temperature above 45 ~C, even more preferably only
at a
temperature above 50 ~C, even more preferably only at a temperature above 75
~C, and
most preferably only at a temperature above 90 ~C.
In one embodiment, the fabric comprises polyvinyl) alcohol. In a preferred
embodiment, the polyvinyl) alcohol is a greater than 95% saponified poly vinyl
acetate, more preferably greater than 98% saponified poly vinyl acetate, even
more
preferably greater than 99% saponified poly vinyl acetate, and even more
preferably is
greater than 99.99% saponified poly vinyl acetate. The fabric layer is an
absorbent
material so that the liquid can be absorbed quickly without spillage onto the
patient's
body. Suitable hot liquid soluble, cold liquid insoluble materials, such as
poly vinyl
alcohol materials, are described in detail in U.S. Patents No. S,181,966,
5,181,9G7, and
5,207,837, the contents of which are hereby incorporated by this reference.
Other
suitable materials for forming the fabric have been listed above with respect
to the
plastic layer.
In addition to these articles, the present invention also provides a disposal
method applicable to the articles. In particular, the present invention
provides a method
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13
of disposing of the articles of the invention, especially where the fabric
layer is soluble
in a second liquid when the second liquid is hot and insoluble in the second
liquid when
the second liquid is cold. The method involves contacting the article with a
sufficiently
hot second liquid for a sufficient period of time to disperse or dissolve
substantially the
article. Thus, if the second liquid is water and the sufficient heat is 90 ~C,
then boiling
the article in water (at l00 ~C) would thereby disperse or dissolve
substantially the
article. In one embodiment, the method is used to dispose of a surgical fabric
such as a
surgical drape. In a preferred embodiment, the articles to be disposed are
introduced
into a washing machine and are agitated in hot water for a period of time
sufficient to
effect disposal. Preferably, the hot water is of a temperature of at least 50
~C, more
preferably at least 90 ~C, and even more preferably at least 95 ~C. In
addition, the
period of time in the machine is from about 2 minutes to about 40 minutes, and
more
preferably is from about 10 to about 30 minutes. Depending upon the
composition of
the article, the runoff from the machine may be released to the sewage system
(if a11
1 S biodegradable) or the insoluble or non-biodegradable components may be
reclaimed via
filtration or dehydration or other known separating processes.
Moreover, the present invention provides the above-described articles, wherein
the coating penetrates into the first side of the fabric layer from 10 % to 90
% of the
thickness of the fabric layer.
In a further embodiment of the present invention, the coating comprises a
fluorocarbon and a wax. Suitable waxes and fluorocarbons include, but are not
limited
to, paraffin waxes and perfluorinated polyacrylate copolymers. One method of
finishing the article is to contact the article with a finishing composition
having the
following ingredients:
In e~dient Percent ($y weight)
1. Pigments 0.01 to 1.0 [ (optional) Such as phthalocyanine
pigment (blue) (Sandoz) and 3,3'-
dichlorobenzidine derivatives (yellow) (Sandoz)]
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I4
2. Wax emulsion 2 to 50 [10 % paraffin wax, 10
melamine resin, 80 % water]
3. Fluorochemical 2 - 50 [perfluorinated polyacrylate copolymer]
4. Binder 0.0l to 30.0 [(optional, use if pigments were
employed) polyvinyl alcohol solution of hot water
soluble binders]
5. Foaming agent 0.0l to 30.0 [surfactant, preferably of a class that
is decomposed by heating during curing]
6. Water Remainder to 100
This composition provides for a wet pick-up of preferably 25 %, but wet pick-
up values from 0 % to 200 % may be suitable depending upon the particular
application, and is applied to one side of the fabric layer, penetrating from
about 10 to
about 90 %, more preferably 20 to about 80 %, and most preferably about 50 %
of the
thickness of the layer, as described elsewhere herein. One device suitable for
the
application of the finishing composition is shown in U.S. Patent No.
4,655,056, the
contents of which are hereby incorporated in their entirety by this reference.
Four of the preferred embodiments are set forth in Figures 1-4. Figure 1 is a
fabric having a waterproof layer on one side. The waterproof layer is the side
that is
placed closest to the patient's body. Figure 2 shows two articles of Figure 1
joined
together at the waterproof layer. This allows the drape to be placed on the
patient on
either side of the drape. The embodiment shown in Figure 3 is the same as the
embodiment shown in Figure l, except a plastic film or sheet layer is attached
to the
waterproof layer. The plastic serves as an additional waterproof layer and/or
a
reenforcement layer. Finally, Figure 4 shows the same embodiment as Figure 2,
except
that a plastic layer is inserted between the two waterproof layers.
Without any intention to limit the scope of this invention in any way, the
article
shown in Figure 1 is preferably, but not exclusively, intended for minor
surgery. The
article absorbs fluids contacting the top surfaces, yet keeps the bottom of
the fabric dry.
The article shown in Figure 2 is also intended for minor surgery. The article
absorbs
fluids from the top, the treated middle layer keeps fluids from penetrating
all the way
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through the article. The article also absorbs fluid ftom the bottom. The
article shown
in Figure 3 is intended for major surgery. The additional plastic layer
further provides
a fluid barrier. Finally, the article shown in Figure 4 is also intended for
major surgery.
As with the article shown in Figure 2, this article provides for absorption of
fluids from
both sides of the surgical fabric.
Generally, the articles of the present invention are made as follows. A chosen
amount of the polymer fibers are formed into a fabric layer of about 0.02 to
30 mil
thickness or having a density of about 10-100 g/mz. The above-specified
finishing
10 composition is applied to the fabric layer, on one side only, using through
foaming
application or by printing application. In this fashion, the finishing
composition does
not penetrate through to the opposite side of the fabric, but instead only
partially
penetrates the layer. Preferably, the finishing composition penetrates from 10
to 90
of the thickness of the fabric layer, more preferably from 20 to 80 % of the
thickness,
15 and most preferably about 50 % of the thickness of the layer. This article
is shown in
Figure 1.
The article shown in Figure 2 is, generally, made as follows. Two of the
articles
of Figure 1 may affixed, either by lamination or by using an adhesive,
together at their
repellent sides to form the article of Figure 2.
The article shown in Figure 3 is, generally, made as follows. The above-
described article (Figure 1 ) is further processed in that one or more plastic
layers are
affixed to the article using either a laminating machine or simply by using an
adhesive,
such as a glue.
The article shown in Figure 4 is, generally, made by one of two processes.
First, an article of Figure 1 and an article of Figure 3 may be affixed
together either by
lamination or by using an adhesive. Specifically, the repellent side of the
article of
Figure 1 is affixed to the plastic layers) of the article of Figure 3.
Alternatively, two of
CA 02268345 1999-04-09
16
A sample .roll of the article shown in Figure 1 was prepared: Cross-
directional
and machine-directional tensile strength was measured and was, on average,
respectively, 6~.9 and 45.5 N/50 mm. In addition, elongation (at break) of the
article
was tested in the cross-directional and machine directional direction and was,
on
average, found to be 16.i and 8.4 %, respectively. In addition, water
repellency was
measured using a Mullen Burst test and occurred at 2.0397 kg/cm- (29.0 psi).
Cross-
directional and machine-directional Elmendorf tear measurements were found to
be 8~ 1
and 1 ~ 72, respectively. The weight of the representative sample was 62.2
g/m'.
Repellency was further evaluated using the Water Impact Penetration Test
(AATCC
Test 42)~nd was found to average 0.7. Finally, repellency was measured by a
Hydrostatic Pressure test and a mean reading of 21.9 cm was measured.
It will be apparent to those skilled in the art that various modifications and
variations can be made in the present invention without departing from the
scope or
1 ~ spirit of the invention. Other embodiments of the invention will be
apparent to those
skilled in the art from consideration of the specification and practice of the
invention
disclosed herein. It is intended that the specification and examples be
considered as
exemplary only, with the true scope of the invention being indicated by the
following
claims.
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