WO2024103104A1

WO2024103104A1 - Chemical barrier laminate and articles therefrom

Info

Publication number: WO2024103104A1
Application number: PCT/AU2023/051118
Authority: WO
Inventors: Jing Liu; Huiqin HAN; Daniel STAPLETON
Original assignee: Ansell Limited
Priority date: 2022-11-15
Filing date: 2023-11-06
Publication date: 2024-05-23

Abstract

A laminate is disclosed herein having a microporous polyolefin film and a non-woven spunbond polypropylene support. A protective garment, a chemical barrier material and a personal protection article comprising the laminate are also disclosed.

Description

CHEMICAL BARRIER LAMINATE AND ARTICLES THEREFROM

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present disclosure claims priority to U.S. Provisional Patent application no. 63/425591 , filed November 15, 2022, the contents of which are fully incorporated by reference herein for purposes of US Patent practice.

FIELD

[0002] The present disclosure is directed to a laminate having chemical barrier properties. More particularly, to a laminate having a non-woven support and a barrier layer for use as, for example, cover garments, such as over-coverall or other protective suits, and the like.

BACKGROUND

[0003] In order to function satisfactorily, personal protective garments and the like must achieve a balance of properties, features and performance characteristics. Suitable materials have, as a principal matter, greatly reduce, if not prevent, the transmission through the article of various biological and chemical liquids and/or airborne contaminates. Such materials may also include particulate material such as, without limitation, lint, mineral fines, dust, skin squames and respiratory droplets. In addition, personal protective articles are often worn for extended periods of time than thus should be comfortable during use while being worn. The weight and flexibility of the protective article has pronounced effect on the utility of the article, as does the strength and ruggedness of the material. Other factors include the article being relatively inexpensive to manufacture, utilizing lightweight materials that enhance the comfort of the wearer during use, and also reduce the cost of such articles.

SUMMARY

[0004] In some embodiments consistent with the present disclosure, a chemical barrier laminate comprises a microporous polyolefin film bonded to a non-woven spunbond polypropylene support. In some embodiments of the laminate, the non-woven spunbond polypropylene support has a gram per square meter (GSM) weight of less than about 26.5 g/m², wherein the non-woven spunbond polypropylene support has a tensile strength in both the machine direction and the cross direction of greater than or equal to about 50N, when determined according to EN ISO 13934-1.

[0005] In embodiments, a laminate, comprises a microporous polyethylene film bonded to a non-woven spunbond polypropylene support, the spunbond polypropylene having a GSM weight of less than about 26.5 g/m²; wherein the nonwoven spunbond polypropylene support has a tensile strength index of less than or equal to about 1.6; wherein the tensile strength index is determined according to the formula: tensile strength index = TS[MD] TS[CD] wherein:

TS[MD] is a tensile strength in a machine direction, determined according to EN13934-1 ; and

[0006] TS[CD] is a tensile strength in a cross direction, determined according to EN 13934-1.

[0007] In embodiments, a protective garment comprises a laminate according to any one or more embodiments disclosed herein. In embodiments, a chemical resistant barrier comprises a laminate according to any one or more embodiments disclosed herein. In embodiments, a personal protection article comprises a laminate according to any one or more embodiments disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1A is a perspective view of a laminate according to an embodiment of the present disclosure.

[0009] FIG. 1 B is a side on view of the laminate shown in FIG. 1a according to an embodiment of the present disclosure.

[0010] FIG. 2A is a schematic view of an embodiment of a process for making the laminate of the present disclosure. [0011] FIG. 2B is a top down view of a laminate produced by the process shown in FIG. 2A, showing the orientation of samples utilized for testing herein and the direction of the tear used to determine tear resistance.

[0012] FIG. 3A is and electron micrograph showing a portion of a comparative non-woven spunbond polypropylene support in which the width of a representative sample of filaments are determined and tabulated.

[0013] FIG. 3B is and electron micrograph showing a portion of a nonwoven spunbond polypropylene support according to embodiments disclosed herein in which the width of a representative sample of filaments are determined and tabulated.

[0014] FIG. 4A is and electron micrograph showing a larger portion of a comparative non-woven spunbond polypropylene support than is shown in FIG. 3A showing the number of filaments per unit area.

[0015] FIG. 4B is and electron micrograph showing a larger portion of a non-woven spunbond polypropylene support shown in FIG. 3B, according to embodiments disclosed herein showing the number of filaments per unit area.

[0016] FIG. 5 is a spider chart showing somatosensory data of the nonwoven side of a laminate according to embodiments disclosed herein.

[0017] FIG. 6 is a spider chart showing somatosensory data of the microporous polyethylene film side of a laminate according to embodiments disclosed herein.

DETAILED DESCRIPTION

[0018] The present disclosure is directed to an improved light weight laminate having a unique balance of performance characteristics and features making the material suitable for use in forming a chemical resistant barrier, as well as for other garment and over-garment applications, such as personal protective equipment applications. Referring to the drawings, an embodiment of the laminate of the present disclosure is illustrated in FIGs. 1A and 1 B, wherein the laminate 10 comprises a microporous polyolefin film 12 bonded to a non-woven spunbond polypropylene support 14, which in the embodiment shown are bonded to one another using a non-continuous layer of adhesive, represented by portions 46 in FIG. 1A and shown in block diagram form in FIG. 1 B. The non-woven spunbond polypropylene support 14 may be formed, for example, of spunbond filaments, and the microporous polyolefin film 12 may be, for example, a microporous polyethylene film. The individual layers of laminate 10 may be laminated, bonded or attached together by various methods including thermal-mechanical bonding, ultrasonic bonding, adhesives, stitching and the like. As shown in FIG. 1A, the laminate 10 includes barrier properties, being at least partially resistant to intrusion from chemical contamination, represented as 52, and further serves as a barrier to particulate matter infiltration represented by 48 and arrow 50. As is also shown in FIG. 1A, the laminate is dimensioned, configured and arranged to allow vapor 54 to pass from the non-woven spunbond polypropylene support 14 side through the microporous polyethylene film 12 providing a “breathable” barrier layer.

[0019] As used herein, Tensile Strength is determined according to EN ISO 13934-1 and Tear Resistance, which is also referred to in the art as “Tear Strength” or “Trapezoidal Tear”, is determined according to EN ISO 9073-4. As shown in FIG. 2B, for purposes herein, a Machine Direction sample (MD) is obtained with the longest axis being parallel to the machine direction of the non-woven spunbond polypropylene support, A Cross Direction sample (CD) is obtained with the longest axis of the sample being perpendicular to the Machine Direction of the non-woven spunbond polypropylene support, parallel to the Cross Direction (CD) of the nonwoven spunbond polypropylene support. It is to be understood that for purposes herein, for determination of tear resistance of the non-woven spunbond polypropylene support in the Machine Direction (MD), the originating tear or cut in the material required by the EN ISO 9073-4 method is actually oriented in the Cross Direction, perpendicular to the longest axis of the sample. Likewise, when determining tear resistance of the non-woven spunbond polypropylene support in the Cross Direction (CD), the originating tear or cut in the material required by the EN ISO 9073-4 method is actually oriented in the Machine Direction, perpendicular to the longest axis of the sample. [0020] As used herein, the terms "layer" or "web" when used in the singular can have the dual meaning of a single element or a plurality of elements. As used herein, the term "laminate" means a composite material made from two or more layers or webs of material which have been bonded or attached to one another. As used herein, the terms "non-woven spunbond support" refers to a web having a structure of individual fibers or filaments that are interlaid, but not in an identifiable, repeating manner as in a knitted or woven fabric.

[0021] Commercially available thermoplastic polymeric materials can be advantageously employed in making the fibers or filaments from which the nonwoven spunbond polypropylene support 14 is formed. As used herein, the term "polymer" shall include, but is not limited to, homopolymer, copolymers, such as, for example, block, graft, random and alternating copolymers, terpolymers, etc., and blends and modifications thereof. Moreover, unless otherwise specifically limited, the term "polymer" shall include all possible geometric configurations of the material, including, without limitation, isotactic, syndiotactic, random and atactic symmetries. As used herein, the terms "thermoplastic polymer" or "thermoplastic polymeric material" refer to a long-chain polymer that softens when exposed to heat and returns to the solid state when cooled to ambient temperature. In addition to polypropylene, exemplary thermoplastic materials may include, without limitation, polyvinyl chlorides, polyesters, polyamides, polyfluorocarbons, other polyolefins, polyurethanes, polystyrenes, polyvinyl alcohols, caprolactams, and copolymers of the foregoing.

[0022] In embodiments, nonwoven webs that can be employed as the nonwoven spunbond polypropylene support 14 of the present disclosure can be formed from filaments comprising propylene, or, in embodiments, are formed from, filaments which consist of or consist essentially of polypropylene. The non-woven spunbond polypropylene support 14 of the present disclosure may be formed by a variety of known forming processes, which in addition to spunbonding may further include airlaying, meltblowing, or bonded carded web formation processes. For example, in an embodiment of the present disclosure, the non-woven spunbond polypropylene support 14 is a spunbond nonwoven web consisting essentially of polypropylene filaments, which has been found advantageous in forming laminate 10. Spunbond nonwoven webs are made from melt-spun filaments. As used herein, the term "meltspun filaments" refers to small diameter fibers and/or filaments which are formed by extruding a molten thermoplastic material as filaments from a plurality of fine, usually circular, capillaries of a spinneret with the diameter of the extruded filaments then being rapidly reduced, for example, by non-eductive or eductive fluid drawing or other well-known spunbonding mechanisms. Lastly, the melt-spun filaments are deposited in a substantially random manner onto a moving carrier belt or the like to form a web of substantially continuous and randomly arranged, melt-spun filaments.

[0023] The non-woven spunbond polypropylene supports melt-spun filaments formed by the spunbond process are generally continuous and have average diameters from about 14 to about 20 based on a representative plurality of measurements, and more particularly, between about 15 and 17 microns.

[0024] Spunbond webs generally are stabilized or consolidated (pre-bonded) in some manner immediately as they are produced in order to give the web sufficient integrity and strength to withstand the rigors of further processing into a finished product. This pre- bonding step may be accomplished through the use of an adhesive applied to the filaments as a liquid or powder which may be heat activated, or more commonly, by compaction rolls. As used herein, the term "compaction rolls" means a set of rollers above and below the nonwoven web used to compact the web as a way of treating a just produced, melt-spun filament, particularly a spunbond web, in order to give the web sufficient integrity for further processing, but not the relatively strong bonding of later applied, secondary bonding processes, such as through-air bonding, thermal bonding, ultrasonic bonding and the like. Compaction rolls slightly squeeze the web in order to increase its self-adherence and thereby its integrity.

[0025] An exemplary secondary bonding process utilizes a plurality of rollers arranged for thermally bonding the spunbond web. The roller arrangement typically includes an upper bonding roll, which may be smooth or patterned, and a lower anvil roll which may also be smooth or patterned, and which together define a thermal patterning bonding nip. The upper and lower rollers may bear a bonding pattern on its outer surface. The pattern roll is heated to a suitable bonding temperature by conventional heating means and is rotated by conventional drive means, so that when the spunbond web passes through the nip, a series of thermal pattern bonds is formed. Nip pressure within the nip should be sufficient to achieve the desired degree of bonding of the web, given the line speed, bonding temperature and materials forming the web. Percent bond areas within the range of from about 10 percent to about 20 percent are typical for such spunbond webs. Microporous Barrier Film

[0026] The microporous polyolefin film 12 may be a top or bottom layer, and can be formed of any microporous film that can be suitably bonded or attached to the non-woven spunbond polypropylene support 14 to yield a laminate 10 having the unique combination of performance characteristics and features described herein. A suitable class of microporous polyolefin film materials includes those comprising a thermoplastic polyolefin polymer and a filler. In embodiments, the polymer from which the microporous polyolefin film 12 is produced comprises polyethylene. In embodiments, the polymer from which the microporous polyolefin film 12 is produced consists of, or consists essentially of polyethylene.

[0027] In embodiments, the polyolefin polymer and the filler (and other) components can be mixed together, heated and then extruded into a mono-layer or multi-layer film using any one of a variety of film-producing processes known to those of ordinary skill in the film processing art. Such film-making processes include, for example, cast embossed, chill and flat cast, and blown film processes. [0028] Generally, on a dry weight basis, based on the total weight of the film, the microporous polyolefin film 12 will include from about 30 to about 60 weight percent of the thermoplastic polyolefin polymer, or blend thereof, and from about 40 to about 70 percent filler. Other additives and ingredients may be added to the microporous polyolefin film provided they do not significantly interfere with the ability of the film layer to function in accordance with the present disclosure. Such additives and ingredients can include, for example, antioxidants, stabilizers, and pigments. In addition to the polyolefin polymer, the microporous polyolefin film 12 may also include a filler. As used herein, a "filler" is refers to particulates and other forms of materials which can be added to the polyolefin extrusion blend and which will not chemically interfere with the extruded film but which are able to be uniformly dispersed throughout the film. Generally, the fillers will be in particulate form and may have a spherical or non-spherical shape with average particle sizes in the range of about 0.1 to about 7 microns. Both organic and inorganic fillers are contemplated to be within the scope of the present disclosure provided that they do not interfere with the film formation process, or the ability of the film layer to function in accordance with the present disclosure. Examples of suitable fillers include calcium carbonate (CaCOs), various kinds of clay, silica (SiO2), alumina, barium carbonate, sodium carbonate, magnesium carbonate, talc, barium sulfate, magnesium sulfate, aluminum sulfate, titanium dioxide (TiO2), zeolites, cellulose- type powders, kaolin, mica, carbon, calcium oxide, magnesium oxide, aluminum hydroxide, pulp powder, wood powder, cellulose derivatives, chitin and chitin derivatives. A suitable coating, such as, for example, stearic acid, may also be applied to the filler particles, as desired.

[0029] As mentioned herein, microporous polyolefin film 12 may be formed using any one of the conventional processes known to those familiar with film formation. The polyolefin polymer and filler are mixed in appropriate proportions given the ranges outlined herein and then heated and extruded into a film. In order to provide uniform breathability, the filler should be uniformly dispersed throughout the polymer blend and, consequently, throughout the film layer itself. For purposes of the present disclosure, a film is considered "breathable" if it has a plurality of microscopic pores.

[0030] Microporous polyethylene films suitable for use herein include those having a weight per unit area from about 28 GSM to about 32 GSM.

[0031] In embodiments, the microporous polyolefin film 12 is a mono-layer microporous polyethylene film, in other embodiments, the microporous polyolefin film 12, in particular the microporous polyethylene film, may comprise a plurality of layers. Each of the layers may include, individually, antioxidants, colorants, antistatic agents, pigments, fillers, processing aids, adhesives, and/or the like. In embodiments, the microporous polyolefin film 12 may be heated to a temperature equal to a temperature below the melting point of the polyolefin polymer and then stretched using an in-line machine direction orientation (MDO) unit to at least about two times (2X) its original length to thin the film and render it microporous. Further stretching of the microporous polyolefin film 12, to about three times (3X), four times (4X), or more, its original length is expressly contemplated in connection with forming the microporous polyolefin film 12 layer of the present disclosure.

[0032] In embodiments, the microporous polyolefin film 12 has an "effective" film gauge or thickness from about 0.01 mm to about 0.1 mm, or from about 0.02mm to about 0.06mm, or from about 0.03mm to about 0.05 mm. The effective gauge is used to take into consideration the voids or air spaces in breathable film layers. For normal, non-filled, non-breathable films, the actual gauge and effective gauge of the film typically will be the same.

Laminate

[0033] Referring now to FIG 2A, an apparatus for continuously preparing a laminate 10 according to the present disclosure is illustrated. The microporous polyolefin film 12 is formed using any type of conventional film forming equipment 20 such as cast or blown film equipment. In embodiments, a precursor of the microporous polyolefin film 12a is passed through a film stretching apparatus 22 to stretch and thin the film to an effective gauge from about 0.01 mm to about 0.1 mm.

[0034] In embodiments, the microporous polyolefin film 12 is formed contemporaneously with the non-woven spunbond polypropylene support 14. However, in other embodiments, the microporous polyolefin film 12 and/or the nonwoven spunbond polypropylene support 14 may be formed separately, in different locations, at different times, and/or the like, and then combined to form the laminate 10. In embodiments, the non-woven spunbond polypropylene support 14, is formed of substantially continuous and randomly arranged, melt-spun filaments, which are extruded, e.g., via an extruder 16, pinch rolled for size via a pinch roller 18, spun in a spinning apparatus 24, the temperature is then adjusted e.g., via air cooling or heating 26, and then subject to stretching via a stretching apparatus 28. The stretched melt-spun fibers or filaments are then laid down on a web forming system 30 wherein the melt-spun fibers are deposited onto a moving continuous forming substrate 32 and randomly arranged to form a web 34. In embodiments, the web may be pre-bonded prior to the web 34 being bonded and the laminate formed by passing the web 34 through a pair of compaction rolls (not shown) to give the web 34 sufficient integrity and strength for further processing.

[0035] In embodiments, the web 34 is cofed with the microporous polyolefin film 12, and in embodiments may further include disposing an adhesive 44 on the web prior to directing the web 34 and the microporous polyolefin film 12 through a bonding system, e.g., compaction rollers 36 which may be heated to aid in bonding the web 34 forming the non-woven spunbond polypropylene support 14 along with laminating the microporous polyolefin film 12 on a side of the non-woven spunbond polypropylene support 14, thereby forming the laminate 10 comprising the microporous polyolefin film 12 bonded to the non-woven spunbond polypropylene support 14.

[0036] In embodiments, one or both of the compaction rollers 36 may be patterned to impart a discrete bond pattern with a prescribed bond area to the nonwoven spunbond polypropylene support 14.

[0037] The temperature of the outer surface of one of the compaction rollers

36 can be varied by heating or cooling relative to the other roller. Heating and/or cooling can affect, for example, the degree of lamination of the individual layers forming the laminate 10. Heating and/or cooling of a pattern roller and/or a smooth roller can be effected by conventional means (not shown) well known in the art. The specific ranges of temperatures to be employed in forming the laminate 10 are dependent on a number of factors, including the types of polymeric materials employed in forming the individual layers of the laminate 10, the dwell time of the individual layers within the nip and the nip pressure between the compaction rollers 36. Prior to the web 34 passing through the compaction rollers 36 the web 34 may be stretched 40 in the machine direction and/or after the laminate 10 exits the nip formed between compaction rollers 36, the laminate 10 may be stretched 42 in the machine direction MD, which is orthogonal to a cross direction CD, and cooled prior to being wound onto a storage roll (not shown) or subjected to further processing.

[0038] Modifications in the above-described process will be readily apparent to those of ordinary skill in the art without departing from the spirit and scope of the present disclosure. Other known means for bonding and laminating the microporous polyolefin film 12 to the non-woven spunbond polypropylene support 14 may be used, provided the resulting laminate 10 has the required properties described herein. Finally, formation of the microporous polyolefin film 12 and/or non-woven spunbond polypropylene support 14 can take place at a remote location, with rolls of the individual layers unwound and fed to the nip formed between compaction rollers 36. Also, for certain applications, it is advantageous to include other components and/ or layers, e.g., adhesives, other barrier materials, other supports, and/or the like.

[0039] In embodiments, the adhesive is applied at a rate of about 0.5 g/m² to about 5 g/m², or from about 2 g/m² to about 4 g/m², or from about 2.8 g/m² to about 3.2 g/m². In embodiments, the adhesive is applied as a continuous layer. In other embodiments, the adhesive is applied as a discontinuous layer or in a pattern. In embodiments, the adhesive comprises a polyurethane, a polyolefin, or a combination thereof. In embodiments, the adhesive is a hot melt polyolefin glue. [0040] In embodiments, an average width of the fibers or filaments which form the non-woven spunbond polypropylene support 14 is from about 14 to about 20 microns, orfrom about 15 to about 17 microns, or from about 15.5 to about 16.5 microns, or from about 15.8 to about 16.3 microns.

[0041] In embodiments, the non-woven spunbond polypropylene support consists essentially of polypropylene.

[0042] In embodiments, the non-woven spunbond polypropylene support 14, has a weight, expressed as a gram per square meter (GSM) weight, of less than about 26.5 g/m², or less than about 26 g/m², or less than about 25.5 g/m², or less than about 25 g/m², or less than about 24.5 g/m², or from about 24.5 g/m² to about 26.5 g/m². [0043] In embodiments, the non-woven spunbond polypropylene support 14 has a tear resistance in a cross direction, and in a machine direction of greater than or equal to about 20N, or greater than or equal to about 25N, or greater than or equal to about 30N, when determined according to EN ISO 9073-4.

[0044] In embodiments, the non-woven spunbond polypropylene support 14, and the laminate 10, have a tear resistance in a cross direction which is greater than a tear resistance determined in a machine direction when each are determined according to EN ISO 9073-4.

[0045] In embodiments, the non-woven spunbond polypropylene support has a tensile strength index of less than or equal to about 1 .6, or less than or equal to about 1.58, or less than or equal to about 1.55, or less than or equal to about 1 .53, or less than or equal to about 1 .5; wherein the tensile strength index (TSI) is determined according to the formula: TSI = TS[MD] -^TSICD] wherein:

TSI is the tensile strength index;

TS[MD] is the tensile strength in a machine direction, determined according to EN13934-1 ; and

TS[CD] is the tensile strength in a cross direction, determined according to EN13934-1.

[0046] In embodiments, the non-woven spunbond polypropylene support 14 has a tensile strength of greater than or equal to about 45N, or greater than or equal to about 50N, or greater than or equal to about 52N in a cross direction when determined according to EN ISO 13934-1.

[0047] In embodiments, the non-woven spunbond polypropylene support 14 has a tensile strength of greater than or equal to about 80N, or greater than or equal to about 90N, or greater than or equal to about 100N, or greater than or equal to about 110N, or greater than or equal to about 115N in a machine direction when determined according to EN ISO 13934-1.

[0048] In embodiments, the laminate has superior somatosensory properties over the prior art. In embodiments, when evaluated using a fabric touch tester (FFT) e.g., SDL Atlas M293-FFT fabric touch tester, available from SDL- Atlas, South Carolina, USA, the laminate according to embodiments disclosed herein has one or more improved somatosensory properties of smoothness, softness and warmness when evaluated using a fabric touch tester (FFT), i.e., an FFT smoothness value, an FFT softness value, and an FFT warmness value, when determined relative to comparative materials in the art. Somatosensory properties may be determined utilizing statistical analysis relative to bending average rigidness, bending work, compression work, compression recovery rate, compression average rigidity, surface friction coefficients, surface roughness, wave amplitude, wavelength, thermal conductivity, maximum thermal heat flux, and the like.

[0049] Statistical analysis is used to correlate human sensations to produce the corresponding FFT values, which are indices predictive of primary touch, hand feel, smoothness, softness and warmth. For purposes herein, a higher FFT value of fabric primary touch/hand - smoothness relates to a smoother surface; a higher FFT value of fabric primary touch/hand - softness means a softer sample; and a higher FFT value of fabric primary touch/hand - warmness means a warmer sample.

[0050] In embodiments, the microporous polyethylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a nonwoven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

[0051] In embodiments, the microporous polyethylene side of the laminate has a FFT smoothness value which is greater than a FFT smoothness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a nonwoven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m². [0052] In embodiments, the microporous polyethylene side of the laminate has a FFT warmness value which is less than a FFT warmness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a nonwoven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

[0053] In embodiments, the non-woven spunbond polypropylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

[0054] In embodiments, the non-woven spunbond polypropylene side of the laminate has a FFT smoothness value which is essentially equal to a FFT smoothness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

[0055] In embodiments, the non-woven spunbond polypropylene side of the laminate has a FFT warmness value which is essentially equal to a FFT warmness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

Embodiments

[0056] Embodiments of the laminate include:

E1. A laminate, comprising: a microporous polyethylene film bonded to a non-woven spunbond polypropylene support, the spunbond polypropylene having a GSM weight of less than about 26.5 g/m², wherein the non-woven spunbond polypropylene support has a tensile strength in both the machine direction and the cross direction of greater than or equal to about 45N, when determined according to EN ISO 13934-1.

E2. The laminate according to embodiment E1 , wherein the non-woven spunbond polypropylene support has a GSM weight of less than about 25.5 g/m².

E3. The laminate according to embodiments E1-E2, wherein the non-woven spunbond polypropylene support has a GSM weight of less than about 25 g/m².

E4. The laminate according to embodiments E1-E3, wherein the non-woven spunbond polypropylene support has a tensile strength index of less than or equal to about 1.6; wherein the tensile strength index is determined according to the formula: tensile strength index = TS[MD] TS[CD] wherein:

TS[CD] is the tensile strength in a cross direction, determined according to EN 13934-1.

E5. The laminate according to embodiments E1-E4, wherein the non-woven spunbond polypropylene support has a tensile strength in both the machine direction and the cross direction of greater than or equal to about 50N, when determined according to EN ISO 13934-1.

E6. The laminate according to embodiments E1-E5, wherein the non-woven spunbond polypropylene support has a tear resistance in both a cross direction and a machine direction of greater than or equal to about 20N when determined according to EN ISO 9073-4.

E7. The laminate according to embodiments E1-E6, having a tensile strength of greater than or equal to about 50N in a cross direction when determined according to EN ISO 13934-1. E8. The laminate according to embodiments E1-E7, having a tensile strength of greater than or equal to about 75N in a machine direction when determined according to EN ISO 13934-1.

E9. The laminate according to embodiments E1-E8, wherein a microporous polyethylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a microporous polyethylene side of a comparative laminate produced from an identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E10. The laminate according to embodiments E1-E9, wherein a microporous polyethylene side of the laminate has a FFT smoothness value which is greater than a FFT smoothness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E11. The laminate according to embodiments E1-E10, wherein a microporous polyethylene side of the laminate has a FFT warmness value which is less than a FFT warmness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E12. The laminate according to embodiments E1-E11 , wherein a non-woven spunbond polypropylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E13. The laminate according to embodiments E1-E12, wherein a non-woven spunbond polypropylene side of the laminate has a FFT smoothness value which is essentially equal to a FFT smoothness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E14. The laminate according to embodiments E1-E13, wherein a non-woven spunbond polypropylene side of the laminate has a FFT warmness value which is essentially equal to a FFT warmness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

E15. A laminate, comprising: a microporous polyethylene film bonded to a non-woven spunbond polypropylene support, the spunbond polypropylene having a GSM weight of less than about 26.5 g/m²; wherein the non-woven spunbond polypropylene support has a tensile strength index of less than or equal to about 1 .6; wherein the tensile strength index is determined according to the formula: tensile strength index = TS[MD] TS[CD] wherein:

TS[CD] is a tensile strength in a cross direction, determined according to EN13934-1.

E16. The laminate according to embodiment E15, wherein the tensile strength of the non-woven spunbond polypropylene support in the cross direction is greater than or equal to about 45N when determined according to EN ISO 13934-1.

E17. The laminate according to embodiments E15-E16, wherein the non-woven spunbond polypropylene support has a GSM weight of less than about 25 g/m². E18. A protective garment comprising the laminate according to embodiments E1-E17.

E19. A chemical barrier material comprising the laminate according to embodiments E1-E17.

E20. A personal protection article comprising the laminate according to embodiments E1-E17.

EXAMPLES

[0057] A laminate according to the present disclosure was produced as disclosed herein (See FIGs. 3B and 4B) using a 26.5 GSM non-woven spunbond polypropylene support bonded to a 30 GSM microporous polyethylene film with 3 GSM of an adhesive according to embodiments disclosed herein.

[0058] The non-woven spunbond polypropylene support was bonded to the microporous film using an upper patterned thermal bonding roll at a bonding temperature between about 90 to 130°C and the lower anvil roller having a temperature from about 90 to 130 °C. The nip pressure formed between the rolls was maintained from about 0.26 to 0.6 Mpa.

[0059] A Comparative Example was formed from a commercially available barrier material ,Alphatech2000™ Nonwoven, (See FIGs. 3A and 4A).

[0060] All measurements shown in the following tables were taken from the body of the respective laminates. All values shown are average values, based upon a plurality of measurements.

TABLE I Non-Woven Spunbond Polypropylene Support Comparison Parameter Example Comparative

Example

EN ISO 9073-4 Tear resistance (CD) | 42.96 N 40.56 N

EN ISO 13934-1 Tensile Strength (MD) | 68.51 N 56.25 N EN ISO 13934-1 Tensile Strength (CD) 50.25 N 34.35 N

EN 863 Puncture Resistance 6.47 N 7.10 N

[0061] These data of Tables I and II clearly illustrate that the laminate 10 of the present disclosure achieves a unique combination of physical characteristics and properties in terms of low basis weight, good strength and durability.

[0062] The laminate was also evaluated for somatosensory properties using a fabric touch tester (FFT) (SDL Atlas M293-FFT fabric touch tester, available from SDL-Atlas, South Carolina, USA). Both sides of laminate were evaluated, i.e., the side having the microporous polyethylene film and the side having the non-woven spunbond polypropylene support. The laminate and the comparative laminate were evaluated for softness, smoothness, and warmness. These data are shown in Tables III and IV, and presented graphically in FIGs. 5 and 6.

Table III

FFT Evaluation of NON-Woven Spunbond Polypropylene side

FFT value Smoothness Softness Warmness Comparative 0.57 0.25 0.42

Example

Example 0.58 0.38 0.43

Table IV

FFT Evaluation of Microporous Polyethylene Film side

FFT value Smoothness Softness Warmness Comparative 0.39 0.26 0.61 Example Example 0.45 0.43 0.56

[0063] As these data show, the laminate according to embodiments disclosed herein has one or more improved somatosensory properties of smoothness, softness and warmness when evaluated using a fabric touch tester (FFT) relative to an essentially identical laminate produced using a non-woven spunbond polypropylene support having a GSM of greater than 26.5.

[0064] While this disclosure has been described by reference to certain specific embodiments and examples, it will be understood that this disclosure is capable of further modifications. This application is, therefore, intended to cover any variations, uses or adaptations of the disclosure following the general principles thereof, and including such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and fall within the limits of the appended claims.

Claims

1. A laminate, comprising: a microporous polyethylene film bonded to a non-woven spunbond polypropylene support, the spunbond polypropylene having a GSM weight of less than about 26.5 g/m², wherein the non-woven spunbond polypropylene support has a tensile strength in both the machine direction and the cross direction of greater than or equal to about 45N, when determined according to EN ISO 13934-

1.

2. The laminate according to claim 1 , wherein the non-woven spunbond polypropylene support has a tensile strength in both the machine direction and the cross direction of greater than or equal to about 50N, when determined according to EN ISO 13934-1.

3. The laminate according to claim 1 , wherein the non-woven spunbond polypropylene support has a tear resistance in both a cross direction and a machine direction of greater than or equal to about 20N when determined according to EN ISO 9073-4.

4. The laminate according to claim 1 , wherein the non-woven spunbond polypropylene support has a tensile strength index of less than or equal to about 1.6; wherein the tensile strength index is determined according to the formula: tensile strength index = TS[MD] TS[CD] wherein:

5. The laminate according to claim 4, having a tensile strength of greater than or equal to about 50N in a cross direction when determined according to EN ISO 13934-1.

6. The laminate according to claim 1 , having a tensile strength of greater than or equal to about 75N in a machine direction when determined according to EN ISO 13934-1.

7. The laminate according to claim 1 , wherein a microporous polyethylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a microporous polyethylene side of a comparative laminate produced from an identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

8. The laminate according to claim 1 , wherein a microporous polyethylene side of the laminate has a FFT smoothness value which is greater than a FFT smoothness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

9. The laminate according to claim 1 , wherein a microporous polyethylene side of the laminate has a FFT warmness value which is less than a FFT warmness value of a microporous polyethylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a nonwoven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

10. The laminate according to claim 1 , wherein a non-woven spunbond polypropylene side of the laminate has a FFT softness value which is greater than a FFT softness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

11. The laminate according to claim 1 , wherein a non-woven spunbond polypropylene side of the laminate has a FFT smoothness value which is essentially equal to a FFT smoothness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

12. The laminate according to claim 1 , wherein a non-woven spunbond polypropylene side of the laminate has a FFT warmness value which is essentially equal to a FFT warmness value of a non-woven spunbond polypropylene side of a comparative laminate produced from an identical, or essentially identical microporous polyethylene film bonded to a non-woven spunbond polypropylene support having a GSM weight of greater than about 26.5 g/m².

13. A laminate, comprising: a microporous polyethylene film bonded to a non-woven spunbond polypropylene support, the spunbond polypropylene having a GSM weight of less than about 26.5 g/m²; wherein the non-woven spunbond polypropylene support has a tensile strength index of less than or equal to about 1 .6; wherein the tensile strength index is determined according to the formula: tensile strength index = TS[MD] TS[CD] wherein: TS[MD] is a tensile strength in a machine direction, determined according to EN 13934-1 ; and

TS[CD] is a tensile strength in a cross direction, determined according to EN 13934-1.

14. The laminate according to claim 13, wherein the tensile strength of the nonwoven spunbond polypropylene support in the cross direction is greater than or equal to about 50N when determined according to EN ISO 13934-1 .

15. A protective garment comprising the laminate according to any of claims 1 through 14.

16. A chemical barrier material comprising the laminate according to any of claims 1 through 14.

17. A personal protection article comprising the laminate according to any of claims 1 through 14.