CA2343242C

CA2343242C - Breathable waterproof laminate and method for making same

Info

Publication number: CA2343242C
Application number: CA002343242A
Authority: CA
Inventors: Laurence Fitch Ellis; Frank Christopher Montie
Original assignee: Brookwood Companies Inc
Current assignee: Brookwood Companies Inc
Priority date: 1998-09-08
Filing date: 1999-09-08
Publication date: 2007-05-01
Anticipated expiration: 2019-09-08
Also published as: AU5814999A; AU748805B2; WO2000013889A1; ES2187194T3; EP1109666B1; JP3825632B2; HK1038536A1; MXPA01002482A; DE69903960D1; EP1109666A1; US6511927B1; CA2343242A1; JP2002524303A; DE69903960T2; PT1109666E; TR200101727T2; ATE227642T1; DK1109666T3

Abstract

The present invention relates to waterproof fabric constructions, and more particularly to waterproof, breathable fabric constructions. The waterproof breathable fabric construction includes a microporous membrane layer and a nonporous layer. Cohesion is provided to the fabric construction through the use of both durable and breathable adhesives.

Description

BREATHABLE WATERPROOF LAMINATE
AND METHOD FOR MAKING SAME
BACKGROUND OF THE INVENTION
Field of the Invention The invention generally relates to a breathable, waterproof textile laminate.
More specifically, the invention relates to textile laminates useful in the production of apparel, industrial, military, and medical products, and the like, which are resistant to contamination, thereby retaining breathability and waterproofness throughout use and numerous cleaning, laundering, or restoration cycles. The invention also relates to a method of producing such a laminate.
Description of the Prior Art Breathable waterproof textile laminates are beneficial in a myriad of applications. For example, breathable waterproof textile laminates are useful in a range of apparel, industrial, medical, and military applications. More particularly, breathable waterproof textile laminates are useful in articles of apparel such as uniforms, workwear, outerwear, active wear, and protective clothing.
Beneficial industrial applications include uses such as filtration. Medical applications for breathable waterproof laminates include uses such as surgical drapes and cast linings. Military applications include use in tents, tarps, and such. Other applications for such laminates include but are not limited to use in mattress pads and animal protective wear.
Breathable waterproof laminates are particularly advantageous in traditional textile fabric applications, such as apparel. Conventional textile fabric which is designed to be waterproof often tends to be uncomfortable to the user, because moisture given off by the body is generally retained within the interior space defined by the textile fabric and thus remains adjacent the user's body. This represents a particular problem to those users who are active while in a moist or wet environment and in those environments which are warm as well as wet, since the incidence of user perspiration therefore is increased.
Retained moisture is particularly problematic in textile fabrics worn as garments. For example, military personnel, sportsmen and athletes often find the discomfort due to perspiration trapped within their garments to be particularly acute.
Therefore, garments are often provided with vents in locations on the garment where it is perceived to be less critical that full waterproofness be provided. For example, vents are often provided underneath the arms of garments (i.e. in the armpit region) or beneath flaps provided in the garment. As will be readily recognized, however, such vents only enable moisture to escape from localized areas within the garment, and the passage is still often inadequate to insure complete wearer dryness and comfort. Furthermore, the provision of such vents requires specially-configured garments which can be more expensive to produce, and the integrity of the waterproofness of the garment can be diminished due to the vent openings.
It is now recognized that, rather than utilizing air vents, merely transporting the water vapor contained in perspiration away from the user provides adequate comfort.
A textile fabric's ability to transport water vapor through its thickness is commonly referred to as its "breathability." Although generally more comfortable, breathable materials often provide unacceptable levels of waterproofness, as the ability of a textile fabric to prevent the passage through of liquid water generally tends to be inversely proportional to the high moisture vapor transmission rate characteristic of breathable fabrics.
However, textile fabric constructions have been developed which attempt this difficult balance between breathability and waterproof properties. In general, these constructions are laminates incorporating a polymeric film, also referred to as a membrane. The primary purpose of the film layer is to repel liquid water without sacrifice to breathability.
Two types of waterproof breathable films are currently available: solution-diffusion films and porous diffusion films.
Solution-diffusion films are extremely hydrophilic films which "solubilize"
water vapor within their molecular chains. These films transport individual water molecules through their thickness by molecular diffusion. Solution-diffusion films are nonporous, thus providing the additional benefit of air-impermeability, or "windproofness." Although breathable and waterproof, the hydrophilic nature of solution-diffusion films cause them to swell and weaken significantly when in prolonged contact with liquid water. Therefore, solution-diffusion films usually exhibit poor durability. The problems encountered in the use of solution-diffusion films are discussed extensively in U.S. Pat. No.
5,660,198.
In contrast, porous diffusion films, commonly referred to as microporous films, are hydrophobic in nature. Porous diffusion films are generally characterized by a network of interconnecting pores which span the thickness of the film.
These pores are too small to allow liquid water to pass, but are large enough to permit water vapor to readily flow through. Expanded polytetraflouroethylene film ("e-PTFE") is a particularly widely known example of such a microporous film. Unfortunately, although microporous films do retain their physical integrity over time, they too lack durability for another reason. Porous diffusion films are adversely affected by exposure to surface active agents present during wear or laundering. For example, surface active agents present in perspiration, such as body oils, salts, and the like, penetrate the microporous membrane over time, coating its pores and causing it to lose its waterproof characteristics.
Coatings have been used to protect the pores of microporous films, in particular e-PTFE films. These coatings are applied to the microporous membrane as either a continuous layer of a liquid solution or a molten application.
Although providing protection, coatings penetrate the surface of the microporous film and stiffen the resulting laminate. Several coated microporous membranes are marketed by W. L. Gore and Associates, Inc., under the tradename GORETEX. Examples of coated e-PTFE fabrics are described in U.S. Pat. Nos. 4,194,041 to Gore et al.
and 5,026,591 to Henn et al,. It is also generally known to bond e-PTFE membranes to a thick, protective film using an adhesive; however, the use of thick protective films likewise increases the stiffness of the resulting laminate. Increasing the stiffness adversely affects the drape, i.e., the feel and flexibility in all directions, of the resulting fabric.
Further, the manner in which the layers comprising the waterproof breathable laminate are joined also affects the performance of the resulting fabric structure. In particular, the layers within the laminate must be cohesive, i.e. move in unison upon flexing. This unitary flexing is especially important in fabrics subjected to pressure testing, such as fabrics for use in military applications. In particular, it is important that the laminate layers act in unison in fabrics subjected to hydrostatic testing.

KC.V. VUN ~ tYA-IHVt:IVI.LytIV VG . JV- O- v . t.~. --tJ . ~,' t , ~ ",",-, , t uv ~ t v ~ .z v nl:u t vn 0. a t nL ~ 02343242 2001-03-08 To provide a cohesive laminate, it is known to use adhesives, fu particular nonbroathable adhasivcs, to bond the layers togather. ~iowevcr, by definition, aonbreathable adhesives, although higlly durable, detract from the overall perforniance of the product by lowering the moisture vapor transmission rata of fife resulting larttinate. The use of such nonbrcathable adhesives in conjunction with hydrophilic films is taught it1 U.S. Patent Nos.
5,660, 918 and 4,761,324.
Breathable adhesives are available far use is waterproof fabric laminates.
I~owever, caution roust be taken in their use, as well. T~reaihal~le adhesives are hydrophilic in nature.
Sinular to solution-diffL~sion films, breathable adhesives lack durability due to their tendency to swell with water and subsequently weaken ovor tune. This issue is especially problematic when bonding stretch resistant materials, which do not yield, or give, when the adhesive swells. The use of breathable adbesives presents particular difficulties in those applications involving launderabiliiy st~as~dards. Further, as with ally coating, the use of excessive amo~.mts of adhosive, breathable or otherwise, results in $ stiffer fabric laminate.
As il~dicated above, a wide v~u~ety of competing factors affect the overall perfrnmance of waterproof, breathable laminates, requiring a difficult balance to be struck to provide vi optimal fabric siructtue. There remains a need for a fabric construction having a high degree of breathabilily and wate~TraoFness, which resists contamination during wear, cleaning, faunderinb, an;l restoratic~u processes, which is durable and possesses superior drape.
r~arthemore, a need exists for a process fur making such a material in an efficient and cost efi°ective mariner.
SUMIVIARY OF 1'FrE IhTVTfNTION
The present invention combines the advant<lges of solution-diffusion films, porous diffusion Ciltns, durable adhesives, ~d broathable adhesives to create a unique textile Ianainate for uce in outdoor garments and other textile applications. The textile lanunates afthe present invention exhibit many advantageous properties. For example, Che textile latrunate3 Of the prc:hont invention are extremely breathable, have superior waterproof properties, have excellent drape, are soft to the touch, and are quiet. The presort invention further provides a method by which to produce the breathable waterpraoftextile laminate of the present invention.
'vlore particularly, tha present invention provides a breathable waterproof textile laminate containing a microporauv membrane bonded to a narxporous Iayer capable of diffusing - 4 - SU6STfTUTE SHEET
AMENDED SHEET

._ _ .. . _ " ~ ... ~ ... . ., ..u.. , v.. .w a t ~w _ _ _ 30-08-2000 ' CA 02343242 2001-03-08 US 009920534 water vapor through its thicl.-ness. In otie advantageous embodiment, a face layer is further adhered to the tnicroporous membrane component, thus providing a three layer laminate. Both durable, i.e. nonhydrophilic, and breathable, i.e, hydrophilic, adhesives are used within the construction to impart cohesion to thE: laraiuate structure, h1 another aspect of ibis advantageous embodiment, a bacl~ing layer is further adhered to the nonporous layer component, u.Sing either a breathable liydrophilic~adhesivc or a durable nonhydrophilic adhesive, thus forming a four layer laminate, In au alternative embodiment, a three layer l:~tninale comprised of a backing layer adhered to the nonporous film component in a noriporous filralmicroporous membrane laminate is provided.
In one advautageaus embodiment, the Rica layer is s durable woven nylon fabric, preferably having a fabric weight rar~gi~; froth 33.9 to 339 gn-Jni2 (1 to 10 ounceslydz}.
Exemplary nticroporous membranes for use ii1 the present invention include expanded polyteiraflouroethylane and similar filras. Er~panded polytei~raflomocthylene (e-P'TT'L} is employed in a particularly advantageous embadiazent of the present invention, The e-P'fFE
may be further cl;araeterized as having an air permeability of from 0.014 to 0.198 m3lnun (0.5 to 7.0 ft'/min), and is preferably from 25 to 75 x 1Q'~m thic)r. fn one advanta~eaus embodimenl, the nonporous layer ht~s a moisiitre vapor transmission rate of from 3000 to 5()(10 gmim'/24hr. In a further aspect of tlae invention, the nonporous layer has a tliiclcness of from 5 to 25 " ~ °'s"'. In a preferred etnbodirneat, the nonporous layer is a nonporous Calm. Exemplary rtouporous filins include polyether polyurethane.
The layers axe adhered using a combination of breathable hydrophilic adhesives and durable nonltydrophilic adhesives. Ex~~nplary breathable hydrophilic adhesives include polyether polyurethane. In one advantageous erabodiment, polyether polyurethane is employed to adhere the microporaus membrane to the nonporous layer. In a :further embodiment, a breathable hydrophilic adhosive is used to bond the nonporous layer to the baking layer.
The durable nonhydrophilic adhesive may also be a variety of tnatetials, including crosslinkable polyester polyurr~dvane. tn a preferred ernbodiatean, crosslu~tcablo palyestc.~
poly~urethaue is ernplnyed to bond the face layer to the rnicroporous merr6rane, part:icultu~ly in these cmbc~diments in which the fa,c:e layer is corl~prised of a stretch resistant eons~cruction.
'the adhesives of the present invention are generally applied in a discontinuous pattern.
In one advanta~,eous aspect of the present invention, adhesive covers fronn 40 to SO% of the - suesrnuT~ shear AMENDED SHEET

bonding surface between the face layer and the microporous membrane, applied in an amount ranging from 8.48 to I 1.87 gm/m2 (0.25 to 0.35 oz/ydz). In a further advantageous aspect, the adhesive applied between the microporous membrane and the nonporous layer, as well as that applied between the nonporous layer and the backing layer, covers 40% to 50% of the respective bonding surfaces, and is applied in an amount ranging from 8.48 to 11.87 gm/m2 (0.25 to 0.35 oz/ydz).
In further embodiments, methods to form the novel laminates of the present invention are provided. These methods include advancing a pair of layers adjacent to each other and adhering them. In further aspects of the invention, the adhesion process comprises applying the adhesive using gravure coating. The layers may be further dried and/or cured as part of the adhesion process.
The present invention provides a waterproof, breathable fabric laminate having superior durability and drape by combining the advantages of several materials. In particular, the durable fabric of the present invention is able to withstand the rigors of use, cleaning, laundering, and restoration. In addition, the present invention provides a soft fabric, which is quiet. The present invention provides the foregoing benefits by utilizing a combination of waterproof, breathable materials in conjunction with a combination of adhesives to provide superior overall performance.
According to an aspect of the present invention, there is provided a breathable and waterproof textile laminate, said laminate comprising:
a microporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to allow water vapor to pass therethrough but small enough to resist the passage of liquid water;
a nonporous layer bonded to said microporous membrane with a discontinuous pattern of adhesive to protect the microporous membrane from contaminants, said nonporous layer comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough; and a fabric layer adhered to one of the microporous membrane and the nonporous layer with a discontinuous pattern of adhesive;
wherein the adhesive between the microporous membrane and the nonporous layer comprises one of a breathable hydrophilic adhesive and a durable nonbreathable adhesive and the adhesive between the fabric layer and the one of the microporous membrane and the nonporous layer comprises the other of a breathable hydrophilic adhesive and a durable nonbreathable adhesive.

According to an aspect of the present invention, there is provided a method of making a breathable and waterproof textile laminate, said method comprising:
advancing a microporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to allow water vapor to pass therethrough but small enough to resist the passage of liquid water;
advancing a nonporous film adjacent to the microporous membrane, the nonporous film being adapted to protect the microporous membrane from contaminants and comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough;
adhering the nonporous film to the microporous membrane with a discontinuous pattern of one of a breathable hydrophilic adhesive and a durable nonbreathable adhesive;
advancing a fabric layer in a machine direction adjacent to one of the microporous membrane and the nonporous film; and adhering the fabric layer to the adjacent one of the microporous membrane and the nonporous film with a discontinuous pattern of the other of a breathable hydrophilic adhesive and a durable nonbreathable adhesive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a diagrammatic exploded view of one advantageous embodiment of the present invention.
FIG. 1B is a greatly enlarged cross-sectional view of the advantageous embodiment provided in FIG. IA.
FIG. 2 is a schematic view of a laminating process associated with several of the aspects of the present invention.
FIG. 3 is a schematic view of the laminating process associated with an aspect of the present invention.
DETAILED DESCRIPTION
The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This - 6a -r~r~ ~~~~ ~ ~=~~ ~tuarvca~N uu : su- a- a : ~~:;,1 : ~~ ~ ~ i ~,~m-. ,-4.a as 30-08-2000 uu, 1 v ~ vu nua ~ my a a , nu ~ 02343242 2001-03-08 invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodin'terits are provided so that this disclosure will be tltarough and complete and will fully convey the scope o f the invention to those skilled in the art. Like numbers refer to like elements throughout.
A l~tnunated fabric is provided having a plurality oi'scquentially-combined layers which in combination achieve a ~fabcic having a high degree of breathability and waterproof~ess, which further retains its breathability and watcrproofvess tJzroughout use, cleaning, laundering, aad restoration, and which also provides adequate drape and softness.
'lha process to produce the laminated fabric of the present invention involves the:
sequential application of layers. In one advantageous embodiment, a four Iayer construction such as that shown in 1~1GS. 1 A and 18 is provided. Tn that ombodvuent, a face layer 4 is secured to a rnicroporous membrane 8 to form a combined structure, thus providing the intermediate laminate 34.
'late face layer 4, comprised of a fabric which is positioned furthest from the user or wearer, is exposed to the environment. Therefore, in general, the face layer 4 is a heavy, durable fabric, preferably chosen to rNithstand eonditi.ons encountered in rough terrain. In one advantageous embodiment, tbo face fabric is a stretch resistant material. The face fabric is desirably selected from those having a weight range of 33.9 to 339 grnlmz (1 to gbout 10 ozlsq.yd), and carp have any desired fiber composition (e.6. sythetic or natural or blends thereon or construction (woven, knit, nonw~oven, and the like). i~or example, fabrics ofwoven nylon have bem 'fmuul to perform will in the instant invention.1n one advantageous embodiment, a 203.43 gmlmz (6 oaJyd2) woven TASLAN nylon fabric is employed.
In addition, thn face layer 4 may be dyed ar printed prior to securing it to the microporous membrane 8, as is known in the art, rlmnicroporous membrane 8 utilized in the present invention is hydrophobic in nature and further characterized by a multiX~liaity of open, interconnecting voids, In general, the microporous membrane also provides strength to the laminate, and has stable chemical properties. T'he micropamus membrane 8 is further selected from those having an air permeability on the order of 0.014 to 0.198 m3lmin (0.50 - 7 cfm (cubic foci per minute)), a thickness of 10 - 80 x l0'bm, arid pore sizes ranging ftotn 0.25 - 10.0 x 10'sm. Membrane weights from 6.7$ to 50.9 grn/m' (0.20 to 1.5 o~Jydz) are useful, with 16.95 to 25.43 (0.50 to 7 - SuBSTITUT~ sH~LT
AMENDED SHEET

lCI.Y. VlIIV~Gf-l1 l~IVLnVL.C,(",~V VV ..JV- O- V . ii~Ji .
w ~ i v ~ a v n a a i va w a i ttu ~-~- ~ ~ i L:.~.n1-~ T.r,~ pa 0.75 o:rJyd'' } preferred. known hydruphobic n~icroporo~ts membranes include e-pTFE. In one advantageous eanbodiui~:ut, the microporous membrane 8 is e-PTFE. ra a further aspect of that advantageous embodiment, c-PTFE film having a thickness of 51 X i O-6m 's'" (?
rails) is amployed. The c~nothods by which such c-PTFE membranes are formed are provided in U.S.
Patent Nos. 3.,953,x66 and 4,187,390, A durable adhesive 6 is generally used to secure the microporous membrane 8 to the taco layer 4. Durable adhesives ate defined herein as those which do twt transmit an appreciable amount of moisture vapor, i.e. they arc nonhydmphilic, and aide thus rlonbreathable. The durable nonhydrophilic adhesive 6 i5 selected to provide good adhesion between the two layets.
~;emplary durable not~hydrophilic adhesives include cross-linked polyester polyureihanes. In one advantageous embodiment, a cross-Iinlced polyester polyurethane adhesive, such as the variety distributed by Polyureth.~rte SpecialticS, Inc. of Lundhurst, New Jersey is employed, although such cross-linked polyester polyurethanes are available from other suppliers as well.
In particular, Adhesiva 490 from Polyurethane Specialties has been Found to be beneficial in the present iilvention.
Referring now to FICr. 2, a laminating process, such as the process employed to bond the face l~syer, shown in F1G. 2 as 24, to the micmporous merubrane, shown in FICr. 2 as 22, is provided. The durable nonhydrophilic adhesive, shown in FICT. 2 as 38, is applied to the microporous membrane in a discontinuou3 pattern.. As used herein, the term "discontinuous"
means thai the adhesive does not completely cover the bonding surface. In the particularly . advantageous embodiment of FIG. 2, the durable adhesive is appli:d by direct gtavure coating 20. It is well known to use engraved gravure rolls to deposit a range o:f discontinuous coating patterns on a substrate. Typical discontinuous adhesive patterns include slanted (also refern;d to as "helical"} lines, dots; and cross h arch. In a preferred emhodi meet of the present invention, the gravure roll applies a discontinuous pattern of adhesive in a series o~P
solid helical )fines, such as depicted ui FIG. 1. The adhesive is desirably applied at a rate of coverage of ~U-SQ%, pr~1'urt~hly ~#0°!0, in wcithts ranging from 8,48 to 11.8? Fualm2 (0.35 to 0.35 oylyd2}, profarably 10.17 gmlm~ (0.3 ozlyd2;).
'1"he coated cnicroporous membrane 22 is then combined with the face layer 24 using heat andlor pressure, such as that supplied by rolls 26 and 28. The coated structure is subjected to a dryinglcuring process, as is known in rue art. 1n this process, the adhesive is initially dries' sussrrruTe sH~eT
AMENDED SHEET

by evaporation and then further cured or cross-linked through the adjustment of temperature and/or passage of time. In one advantageous embodiment, the drying/curing process is accomplished using a single oven. In such a single oven embodiment, typical dry/cure conditions involve subjecting the coated substrate to hot air between 66 to 121°C (150 to S about 250°F), with a dwell time between about 10 to about 60 seconds.
Following the dry/cure process, the intermediate laminate is collected on a take-up roll 30.
Returning now to FIG. 1A, the microporous membrane 8 is laminated to a nonporous layer 12, thus forming the laminate 36. The nonporous layer 12 is water vapor permeable and extremely hydrophilic. The nonporous layer 12 is further desirably selected to have a thickness on the order of about 5-15 x 10-6m, and a moisture vapor transmission rate (as tested according to ASTM E-96, Proc. B) of about 3000-5000 gm/m2/24hr. The water vapor permeable nonporous layer 12 is generally a film, preferably chosen from films formed from polymers such as polyurethane. In one particularly advantageous embodiment, an extruded nonporous hydrophilic thermoplastic polyurethane (TPUR) film is employed.
One particular TPUR film which has been found to perform well in the instant invention is TransportTM TX 1540 sold by Omniflex Flexible Films & Composites of Greenfield, MA, although such TPUR films are available from other suppliers, as well.
TransportTM TX 1540 is a thermoplastic polyurethane extruded film (as opposed to a blown film) which has very high moisture vapor transmission properties. In particular, the moisture vapor transmission of TransportTM TX 1540 is 3000-5000 gm/m2/24h based on ASTM Test B-96, procedure B.
TransportTM TX 1540 is extruded onto a O.OSlmm (2 mil) polyethylene (PE) carrier film to provide support to the TPUR during processing. Because TransportTM TX
1540 is produced by casting onto a carrier film, it enables production of a TPUR film without use of materials, such as fillers and lubricants, that can result in later surface contamination.
Further, TransportTM TX 1540, a polyether polyurethane, is known to have the following properties: a specific gravity of about 1.2 g/cc using ASTM D-792, a Shore hardness measured using ASTM D-2240 of about 80A, a tensile strength of 27.6 x 106 to 34.5 x 106 Pa (4000-5000 psi) using ASTM D-412, an elongation of about 600-700% using ASTM-412, a modulus at 100% of 3.79 x 106 Pa to 4.48 x 106 Pa (550-650 psi) using ASTM D-412, and a tensile set at 200% using ASTM D-412 (at 200% elongation) of less than 40%.

w.r . v my ~ cc n uwa:rvv.muv vv . vv- c~- v . c~ -.~c . ~.t.1 1 ~ G~.Ir!-W
"f~ t5~
vu ~ i a ~ vv nuv i vv u~ a i nu ~ 02343242 2001-03-08 The na>lporous layer 12 is bonded to the microporous membrane 8 using a breathable adhesive 10. The tmn "breathable adhesive" as used herein refers to $
hydrophilic adhesive.
1'he breathable hydrophilic adhesive is selected to provide high water vapor transmission, as well as good adhesion between the layers. Exemplary breathable adliesives include polyether polyurethane. In particular, moisture cured polyctber polyurethane adhesives have been fotuid to perform well in the invmtiion. In one advantageous emhodirtlent, ~l 379 Clear Comfortex Basecoat sold by R.9ffi & Sans Ins. oFVi%ilmiugian, Mass. is applied, alth.ougtl such moisture cured polyether polyurethane adhesives are available frora other suppliers, as well.
Referring now to FIG. 3, a process is provided for laminating a noapoinus layer 12 cast unto a carriar film 32, e.g. Transport TX 1540, with a microporous uteinbrane 8. The breathable hydrolahilic adhesive 10 is applied to the nucropomus membrane 8 iu a discontinuous pattern. Tn the advantageous embodinurnt provided in FTG. 3, the breathable hydrophilic adhesive is appliad by direct gravure coating 20. Although several discxrntitiuous patterns may be acceptable, in a preferred embodiment the gravure roll applies a discontinuous pattern of breathable hydrophilic adhesive 10 is a series oi'solid helical lines, as indicated in FIG. 1A. Tlie adhesive is desirably applied at a weight of 8.48 - 11,87 gmlm2 (0.2~ - 0.3~
oxlyd''), preferably 10.17 gmlnt~ (0.30 oilyd=), and a coverage o~(~ 40 - 50%, preferably 40%.
In one advantageous embodiment, the adhesive is applied as a 44 weight percent solution in a mixture of solvents, such as a mixture of methyl ethyl ketone and toluene.
As shown in FIG. 3, the coated rnicroporous membrane 8 is combined with the nonporous layer 12 using heat andlor pressure, such as that supplied by rolls 26 and 28. Tt is iraportant that the tension of the various layers match when bonding nariporous layers which are elastomeric, to avoid imparting curl to the finished laminate.
rollowin6 contact, the cnated structure is subjected to a dryilig/curing process, as is known in the att. In this prurc,ss, the: adhesive is desirably driad by evaporating solvents there&orn and the dried coating is subsequently ctucd or cmss-linked through tire adjustment of temperature andlor lapse of time, In one advantageous embodimont, the drying/curiag process is accomplished using a single oven. In such a single oven embodiment, typical dxy/cure conditions involve subjecting the coated substrate to hot air beivveea 66 to 121 °G (1S0 to Z50 °
F), with a dwell time between 10 tcy 60 seconds. 1'n thane embodiments in which the water IO - SUBSTITUTE SHEET
AMENDED SHEET

A\. Y . Y W ~ W 11 :W L, W .y V V . V V - U - V r GG ~ JJ . l..<. l 1 I GLhh W a Iv a r nuu tvn a a I Ialr ~ 02343242 2001-03-08 pem~eabIe nonporous film is supplied on a carrier film 32, the carrier film 32 is removed from the laminate construction foliawizig the dr~hnglcuring process.
Returning now to the advantageous embodiment provided in FIG, I A, the nonporous layer 12 i$ bonded tn a backing layer. 16, thus forTUing the laminate 18. The hacking layc~ 1b, placed adjacent to the user or wearer, is a typically a light weight fabric, chosen primarily for comfort. The backing fabric may be fon~ed from nylon or polyester having a weight ranging from 16.95 gmlm2 (Q.5 ozlsq.yd) w 135.6? gmJmz (4 oz/sq,yd). In one 2dvautageous embodiment, the backing layer 16 is desirably a tricot kr~lt nylon fabric.
The backing layer 16 is primarily iutcAded to protect the nonparous layer 12 ~fxoan abrasion and the like. Therefore, the backing layer 16 is generally recomoended in those embvdit<ucnts in which the waterproof breathable laminate is intended for direct contact with the user or wearer. Such an embodiment is illustrated as 18. Alternative embodirncnts employing a.
separately hung lining da nal require the backing layer I 6. In these embodiments, the laminate shown as 36 is instead incorporated into the garment or other aWcle, In an alte~rnativo aspect of the preset invention, the face layer 4 ig not required. Tn this embodiment a three layer laminate comprised of a backing layer 16, a nonporous layer 12 and a microporous membrane B is inco~poratad directly into the garment or other article. in such an erubodiment, the backing layer is adhered to a nonporous layer bonded to a mieroporous membrane. Thtee layer constructions containing a backing layer are incorporated into garments and other articles having a separately hung face fabric.
In those embodiments forming the laminate 18, the nonp~orous ~Im 12 is typically bondul to the baclcins Iayer 16 using a breatlu~ble hydrophilic adhesive 14~, such as the breathable hydrophilic adhesive 10 used to eombint: the nonporous layer 12 to the micraporous me~nbraue 8. The breathable hydrophilic adhesive is selected to provide high water transmission values, as well as good adhesion between the layers, Exemplary breathable hydrophilic ac'()lesives include palyether polyurethane. In particular, raoisturc-cured polyether polyurethane adhesives, such as the type sold by Raft & Swanson, Inc. of Wilmington, Mass.
undrrr the lrader~arna 51379 Clear ComforKcx Ba.SC:CO~tt, have been found to perform well in the invention, although such adhesives are available from other suppliers as welt.
The breathable hydrophilic adhesive 14 is applied to the baehing layer 16 in a discontinuous pattern, as illustrated in FIG. 1 A, such as by direct gravuxe coating on the AMENDED SHEET

l~l.V. VW ~L.~11 urJVL:W.l4~v UtJ .JU- U- U . Gs.~aJJ . 1.1.111 C1.11!-n ty.~y t,~y uL ~ s v . a . nuu t my a a ~ nu ~ Opg43242 2001-03-08 US 009920534 backing layer. Although other discontiQUou.R patterns may be acceptable, in a pactictliarly advantageous ctabodiment the gi~avure roll applies a discontinuous pattena of adhesive in the form of a series of dotted helical lines. The adhesive is desirably applied at a weighs of 8.48 -11.87 gntlm'' (0.25 - 0.35 ozJyd~), preferably 14,17 gm/m' (0.30 ozlyd2), and a coverage of 40 - 50%, preferably 40°/n. In a prefeire,i form of the invention, the breathable adhesive is supplied as a 40 weight percent solution in a solvent, such as a mixture of ruethyl ethyl ketone and toluene.
the coated backing fabric is then combined with the nonporous film in a process similar to that illustrated in FIG. 2 (but wrath the various layers interchanged). The nonporaus film is provided to this step in khe form of an intermediate laminate structure, slwwn in FIG. lA as 3b.
The layers are combined using heat artdlor pressure, such as that applied by rolls. The coated laminate structure is subjected to a cuying/curing process following contact, as is laiown in the art. The adhesive s s dried by evaporation and fttrther cured or cross-linlced through the adjustment of temperatcu~e and/or passage of time. In one advantttgeotts embodiment, the dryinglcuring process is accomplished using a single oven. In such a single oven embodiment, typical dry/curc conditions involve subi~octing the coated substrate to hot air between bb to 121 °C (150 to 250° F), with a dwell time between lU to 6Q
seconds. Following the dryinglcuring process, the four layer latuinate is collected on a take-tip roll.
The laminate shown in F1G. YA as 18 and produced according to the instant invention has a high moisture vapor transmission rate, as well as a good level of hydrostatic resistance. A
sample of the laminate fabric,l8 was produced according to the instant invention for testing.
lni>sally, ~n interrnadiate laaninate was formed by bonding a 203.4 gmlm~ (6 ozJyd2) woven TASLA.~1 nylon face fabric to a O,OSOSmtu (2 mil) thiclc e~PTIvL metrtbrane with an air perraeabiliry of between 0.UI4 to 0.198 m3lm.in (0.5 to ?.0 cfat) using Adhesive 4901'~rom Polyurethane Specialties, a nonhydtophilic cmsslinlcable polyester polyurethane. The Adhesive 490 was applied by direct gravure at a weight of 10.17 gtnlm~ (0.3 oiJyd'') and 40"/° coverlge.
The e-PTFr was bonded in turn to a Transport TX 1540 water permeable polyurethane filth having a thickness of 7 ~, lU~m (G.0003") using Comfortex 51379 palyether polyurethane. The Comfortex 51379 was likewise applied by diroct gravurG at a waisht of 10.17 gmlml (0.3 oT.lyd2) and 40°lo coverage. 1'he Transport TX 1540 was subseduently adhered to a 40.69 gn~/rn2 (1.2 oz/yd'') nylon hit fabric, also using Comfortex 51379 polyether polyurethane. The AMENDED SHEET

;~l:V. V()N:1-.NH NIUt:.lVl.tlLlV Uti :iiV- if- V : GG~a:f . (...l..1 l l J;(rlYl-i ~-y.~ Zi~
- 00 ~u ~ 1 U ~ U V nun 1 VII 0. L 1 (1L ~ 02343242 2001-03-08 US 009920534 Comfortcx 51379 was applied by direct gravure at a weight of 10.17 gmlm2 (0.3 ozlyd~) and a 40"/o coverage.
This sa.rnpte wxs tested according to ASTM E-96 Procedure B~ and found to have a moisture vapor taransmission rate of 3600 - 6300 gmlsq.ml24hr, with a typical value of 5000 gmlsq.m/24hr. These values correlate to a minimum of 600 grn/sq.m/24hr, typically 750 gm/sq.ml24hr, using ASTM E-96, Procedure B.
The laminate retained its performance over time, yielding a moisttue vapor traasrpissian rate of 5900-6400 gmlsq.ml24h after S washes, similarly based on ASTM E-96 Procedure BW.
Therefore, it was apparent that the lt~minates avoided the decrease in performance commonly experienced in prior art materials as a result of contaminatian from surfactants and the like. In addition, these samples were tested according lo foreign country test methods a.std fauna to r~rain high moisture vapor transmission rates following repeated washings.
The laminate was also t",-stod using A5TM D-3393, and found to have a hydrostatic nsistanee of greater than 2.76 x 105 Ya (40 psi), typically 5.86 x ! OS Pa (85 psi). The hydrostatic resistance was determined using ASTM Test Method 5512 {hed. Std.
191 ). rurther, the lat-ninate exlxibited a minimum regiatance to leakage of 50 cm of water prossure for a duration of5 min, typically 300 cm aFwater pressure for p duration of 5 min, determined using ASTM Test Method 33 !6 (Fed. Std. 191). In addition to these performance characteristics, the laminate is soft, quiet (which ten be importE~nt in many military and sportsmen's applications), comfortable, and lightweight.
Many modivcations and other. embodiments of the invention 'will come to mind lo one sldllc:d in the art to which this invention pertains having the benefit of the teachings presented in the foxcgoiug descriptions and the asaaciated drawings. 'therefore, it is to be understood that the itsveuiion is not to 6c limited to tree specific embadiments disclosed alai that modifications and other embodiments :ire intended.
- 13 - Sli85TITUTE SHEET
AMENDED SHEET

Claims

THAT WHICH IS CLAIMED:

1. A breathable and waterproof textile laminate, said laminate comprising:
a microsporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to allow water vapor to pass therethrough but small enough to resist the passage of liquid water;
a nonporous layer bonded to said microporous membrane with a discontinuous pattern of adhesive to protect the microporous membrane from contaminants, said nonporous layer comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough; and a fabric layer adhered to one of the microporous membrane and the nonporous layer with a discontinuous pattern of adhesive;
wherein the adhesive between the microporous membrane and the nonporous layer comprises one of a breathable hydrophilic adhesive and a durable nonbreathable adhesive and the adhesive between the fabric layer and the one of the microporous membrane and the nonporous layer comprises the other of a breathable hydrophilic adhesive and a durable nonbreathable adhesive.

2. A breathable and waterproof textile laminate according to Claim 1, wherein the adhesive between the microporous membrane and the nonporous layer comprises a breathable hydrophilic adhesive.

3. A breathable and waterproof textile laminate according to Claim 1, wherein the fabric layer comprises a face layer foamed of a fabric which is durable when exposed to ambient conditions and which is adhered to the microporous membrane.

4. A breathable and waterproof textile laminate according to Claim 1, wherein the fabric layer comprises a backing layer which is adhered to the nonporous layer to be adjacent to the user.

5. A breathable and waterproof textile laminate according to Claim 1, further comprising a second fabric layer adhered opposite the first fabric layer to the other of the microporous membrane and the nonporous layer with an adhesive comprising one of a breathable hydrophilic adhesive and a durable nonbreathable adhesive.

6. A breathable and waterproof textile laminate according to Claim 5, wherein the first fabric layer comprises a face layer formed of a fabric which is durable when exposed to ambient conditions and which is adhered to the microporous membrane and the second fabric layer comprises a backing layer which is adhered to the nonporous layer to be adjacent to the user.

7. A breathable and waterproof textile laminate according to Claim 5, wherein said breathable hydrophilic adhesive bonding said microporous membrane to said nonporous layer covers from 40 to 50 % of the bonding surface therebetween.

8. A breathable and waterproof textile laminate according to Claim 2, wherein said microporous membrane is expanded polytetrafluoroethylene.

9. A breathable and waterproof textile laminate according to Claim 8, wherein said expanded polytetrafluoroethylene has an air permeability of from 0.5 to 7.0 ft3/min.

10. A breathable and waterproof textile laminate according to Claim 8, wherein said expanded polytetrafluoroethylene has a thickness from 25 × 10 -6m to 75 × 10 -6m.

11. A breathable and waterproof textile laminate according to Claim 2, wherein said nonporous layer has a moisture vapor transmission rate of from 3000 to 5000 gm/m2/24 hr.

12. A breathable and waterproof textile laminate according to Claim 11, wherein said nonporous layer has a thickness of from 5 to 25 × 10 -6m.

13. A breathable and waterproof textile laminate according to Claim 11, wherein said nonporous layer is polyether polyurethane,

14. A breathable and waterproof textile laminate according to Claim 2, wherein said durable nonhydrophilic adhesive is crosslinked polyester polyurethane.

15. A breathable and waterproof textile laminate according to Claim 2, wherein said breathable hydrophilic adhesive is polyether polyurethane.

16. A breathable and waterproof textile laminate according to Claim 3, wherein said face layer comprises a stretch resistant construction bonded to said microporous membrane.

17. A breathable and waterproof textile laminate according to Claim 2, wherein said durable nonhydrophilic adhesive bonding said face layer to said microporous membrane covers from 40 to 50 % of the bonding surface therebetween.

18. A breathable and waterproof textile laminate according to Claim 2, wherein said adhesive bonding said backing layer to said nonporous layer covers from 40 to 50% of the bonding surface therebetween.

19. A breatbable and waterproof textile laminate according to Claim 1, sand laminate comprising:
a face layer formed of a fabric which is durable when exposed to ambient conditions;
a microporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to allow water vapor to pass therethrough but small enough to resist the passage of liquid water, acid microporous membrane being bonded to said face layer with a durable nonbreathable adhesive;
a nonporous layer bonded to said microporous membrane with a breathable hydrophilic adhesive to protect the microporous membrane from contaminants, said nonporous layer comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough; and a backing layer formed of a fabric which is bonded to said nonporous layer with a breathable hydrophilic adhesive.

20. A breathable and waterproof textile laminate according to Claim 19, wherein said backing layer is a knit fabric formed from nylon.

21. A breathable and waterproof textile laminate according to Claim 19, wherein said face layer comprises a stretch resistant construction.

22. A breathable and waterproof textile laminate according to Claim 19, wherein said nonporous layer is polyether polyurethane.

23. A breathable and waterproof textile laminate according to Claim 19, wherein said breathable hydrophilic adhesive is polyether polyurethane.

24. A breathable and waterproof textile laminate according to Claim 19, wherein said durable nonhydrophilic adhesive is crosslinked polyester polyurethane.

25. A method of making a breathable and waterproof textile laminate, said method comprising:
advancing a microporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to allow water vapor to pass therethrough but small enough to resist the passage of liquid water;
advancing a nonporous film adjacent to the microporous membrane, the nonporous film being adapted to protect the microporous membrane from contaminants and comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough;
adhering the nonporous film to the microporous membrane with a discontinuous pattern of one of a breakable hydrophilic adhesive and a durable nonbreathable adhesive;
advancing a fabric layer in a machine direction adjacent to one of the microporous membrane and the nonporous film; and adhering the fabric layer to the adjacent one of the microporous membrane and the nonporous film with a discontinuous pattern of the other of a breathable hydrophilic adhesive and a durable nonbreathable adhesive.

26. A method of making a breathable and waterproof textile laminate according to Claim 25, wherein the adhesive between the microporous membrane and the nonporous layer comprises a breathable hydrophilic adhesive.

27. A method of making a breathable and waterproof textile laminate according to Claim 26, wherein said step of advancing a fabric layer further comprises advancing a face layer adjacent to the microporous membrane.

28. A method of making a breathable and waterproof textile laminate according to Claim 26 , wherein said step of advancing a fabric layer further comprises advancing a backing layer adjacent to the nonporous film.

29. A method of nicking a breathable and waterproof textile laminate according to Claim 26 , wherein the nonporous film further comprises a carrier layer which is removed from the nonporous film after adhering the nonporous film to the microporous membrane.

30. A method of making a breathable and waterproof textile laminate according to Claim 26, wherein said step of adhering the microporous membrane to the nonporous film further comprises applying a discontinuous layer of adhesive.

31. A method of making a breathable and waterproof textile laminate according to Claim 30, wherein said step of applying a discontinuous layer of adhesive further comprises gravure coating the microporous membrane with the adhesive.

32. A method of making a breathable and waterproof textile laminate: according to Claim 26, wherein said step of adhering the fabric layer to the adjacent one of the microporous membrane and the nonporous film further comprises applying a discontinuous layer of adhesive.

33. A method of making a breathable and waterproof textile laminate according to Claim ?6 wherein said step of applying a discontinuous layer of adhesive further comprises applying the discontinuous layer of adhesive by gravure coating.

34. A method of making a breathable and waterproof textile laminate according to Claim 25, said method comprising:
advancing a face layer in a machine direction;
advancing adjacent to the face layer a microporous membrane comprising a hydrophobic film having a plurality of pores of a size large enough to show water vapor to pass therethrough but small enough to resist the passage of liquid water;
adhering the microporous membrane to the face layer with a durable nonbreathable adhesive;
advancing a nonporous film adjacent to the microporous membrane, the nonporous film being adapted to protect the microporous membrane from contaminants and comprising a hydrophilic material capable of allowing the diffusion of water vapor therethrough;
adhering the nonporous film to the microporous membrane with a breathable hydrophilic adhesive ;
advancing a backing layer adjacent to the nonporous film, the backing layer being adapted to protect the nonporous film from abrasion; and adhering the backing layer to the nonporous film with a breathable hydrophilic adhesive.

35. A method of making a breathable and waterproof textile laminate according to Claim 34, wherein the nonporous film is advanced on a carrier layer which is removed from the nonporous film after adhering the nonporous film to the microporous membrane.

36. A method of making a breathable and waterproof textile laminate according to Claim 34, wherein said step of adhering the microporous membrane to the face layer further comprises applying a discontinuous layer of durable nonhydrophilic adhesive.

37. A method of making a breathable and waterproof textile laminate according to Claim 36, wherein said step of applying a discontinuous layer of durable nonhydrophilic adhesive further comprises gravure coating the microporous membrane with the adhesive.

38. A method of making a breathable and waterproof textile laminate according to Clam 34, wherein said step of adhering the nonporous film to the microporous membrane further comprises applying a discontinuous layer of breathable hydrophilic adhesive.

39. A method of making a breathable and waterproof textile laminate according to Claim 38, wherein said step of applying a discontinuous layer of breathable hydrophilic adhesive further comprises gravure coating the microporous membrane with the adhesive.

40. A method of making a breathable and waterproof textile laminate according to Claim 34, wherein said step of adhering the backing layer to the nonporous film further comprises applying a discontinuous layer of breathable hydrophilic adhesive.

41. A method of making a breathable and waterproof textile laminate according to Claim 40, wherein said step of applying a discontinuous layer of breathable hydrophilic adhesive further comprises gravure coating the backing layer with the adhesive.

42. A method of making a breathable and waterproof textile laminate according to Claim 34, wherein said steps of adhering the microporous membrane to the face layer, adhering the nonporous film to the microporous membrane, and adhering the backing layer to the nonporous film further comprise the steps of drying and curing said adhesives.