Microporous film and textile material

Abstract

To provide a novel, improved, or modified polyolefin microporous film for a textile material that feels soft, smooth, quiet to movement, and / or has a low friction coefficient, desired in specific textiles, garments, and / or related end uses.SOLUTION: A microporous film comprises a mixture of at least one polyolefin and at least one block copolymer. The polyolefin is polypropylene, polyethylene, poly-1-butene, poly-4-methyl-1-pentene, polyhexene, polyoctene, and / or blends, mixtures, or combinations thereof. The block copolymer comprises two or more monomers with a molar fraction between 1% and 2%.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This application is a continuation of U.S. Provisional Application No. 61 / 723,058, filed November 6, 2012. and U.S. Provisional Application No. 61 / 892,730, filed Oct. 18, 2013 (both of which are incorporated herein by reference).

[0002] According to at least selected embodiments, the present invention relates to new, improved or modified porous membranes, fibers, porous fibers, products made from such membranes, fibers or porous fibers and / or related methods of manufacture, uses and / or the like. According to at least certain embodiments, the present invention relates to new, improved or modified microporous membranes or membranes, fibers, microporous fibers, materials or layers made from such membranes, fibers or porous fibers, etc., for use in textile materials, garments, products and / or textile related applications. According to at least certain embodiments, the present invention relates to novel, improved or modified microporous membranes or membranes, fibers or microporous fibers, e.g., rigid or porous fibers, microporous fibers, shaped fibers, materials, layers or fabrics made from such fibers or microporous membranes, including fabrics, nonwovens, knits, bonded, flocked and / or other woven fabrics, laminates, composites, garments, etc., such membranes, fibers or porous fibers are preferably one or more block copolymers, e.g., copolymers comprised of two or more polyolefin monomers, or such membranes, fibers or porous fibers are preferably polymers, e.g., one or more copolymers, e.g., block copolymers or impact copolymers comprised of two or more polyolefins, or preferably, one or more polyolefins. According to at least one specific embodiment, the present invention provides a novel, improved or modified microporous membrane or membranes, fibers or microporous fibers, which may be formulated with one or more block or impact copolymers in combination with a polyolefin to improve the composition, characteristics, performance or other properties of the membrane, fiber, porous fiber, material, layer or fabric and / or the membrane, fiber, material, layer or fabric from such membrane, fiber or porous fiber, such as improved characteristics, performance or properties of microporous polyolefin membranes and / or fabrics or polyolefin fibers for or for textile end uses, such as improved hand, softness, quietness and / or surface coefficient of friction.According to at least one specific selected embodiment, the present invention is directed to novel, improved or modified polyolefin materials or compositions in which one or more polyolefins are compounded or blended into one or more block or impact copolymers. Also, according to the least specific embodiment, the present invention is directed to novel, improved or modified polyolefin materials or compositions in which one or more polyolefins are compounded or blended into one or more (preferably one or more, block or impact copolymers), and the blend or combination affects the performance properties of hand, drape, motion quietness, and / or surface coefficient of friction of microporous polyolefin membranes, materials, layers and / or fibers made from such polyolefin materials or compositions for use in textile products and / or textile related end uses. [Background technology]

[0003] At least one particular polyolefin (PO) microporous membrane and microporous fiber (or materials made therefrom) is known to be waterproof (or at least water resistant) and breathable due to its chemical composition and structure. Examples of polyolefin (PO) microporous membranes and hollow fibers known to be waterproof (or water resistant) and breathable of this type include the Celgard® Z series membranes or Celgard® hollow fibers manufactured by Celgard Corporation of Charlotte, NC. Porous membranes and fibers tend to be perceived as undesirably stiff and plastic-like and therefore are not widely used in textile garments and / or related textile materials, laminates or products, or other textile end products or applications. Summary of the Invention [Problem to be solved by the invention]

[0004] New, improved, modified polyolefin microporous membranes, polyolefin fibers and / or polyolefin microporous fibers, and / or new, improved, modified compositions, characteristics, performance and / or properties made therefrom, e.g., improved compositions, performance and / or properties ... There is a need for materials, layers, and / or fabrics that have improved, better, or the desired hand feel, smoothness, quiet movement, and / or low coefficient of friction for a particular textile, garment, and / or related end use. [Means for solving the problem]

[0005] According to at least selected embodiments, the present invention is directed to novel, improved or modified microporous membranes, fibers and / or microporous fibers that can address the above needs or problems and are intended for use in textiles, clothing, textile clothing, textile materials or textile related applications. According to at least one particular embodiment, the present invention is directed to novel, improved or modified microporous membranes, membranes, fibers and / or microporous fibers that include one or more polyolefins (PO), one or more copolymers, such as block or impact copolymers of polypropylene (PP) and polyethylene (PE), or one or more polyolefins (PO), blended with one or more copolymers, such as block or impact copolymers of polypropylene (PP) and polyethylene (PE). According to at least one particular embodiment, the present invention relates to new, improved and / or modified porous membranes or films, fibers and / or porous fibers made therefrom comprising polyolefins, preferably including polypropylene and polyethylene, and one or more block or impact copolymers, or to materials, layers, fabrics, composites, etc. made from or including membranes, coatings, fibers or hollow fibers made from polyolefins and one or more polymers, or one or more block or impact copolymers, preferably including polypropylene and polyethylene.

[0006] In another embodiment, the present invention relates to new or improved and / or modified membranes, coatings and / or fibers, such as microporous membranes, fibers and / or microporous fibers comprised of polyolefin blended with one or more block copolymers, such as copolymer polyolefins including, but not limited to, polypropylene, polyethylene, polyester fibers, 1-butene, poly-4-methyl-1-pentene, polyhexene, polyoctene and / or blends, mixtures or combinations thereof. When the polyolefin membrane or fiber is comprised of polyolefin blended with one or more block or impact copolymers, the modified membrane or fiber is modified microporous membrane, fiber or microporous fiber, or to methods of designing materials, layers, composites, laminates or fabrics with targeted enhanced performance properties for textile related end uses. By varying the compositional selection of the modified compositions, membranes or fibers, or materials, polymeric blends or chemical structures of the compositions, in the membranes or fibers, or materials, layers, composites, laminates or fabrics made therefrom, performance properties such as hand, flexibility, quiet movement, and / or low surface coefficient of friction can be affected, thereby producing microporous polyolefin membranes, fibers, microporous fibers or materials, layers, composites, laminates or fabrics having, for example, a silky feel, good hand, soft smoothness, quiet movement and / or low coefficient of friction.

[0007] According to at least selected embodiments, the invention is directed to novel, improved or modified porous membranes, products made from such membranes, fibers or porous fibers, and / or related methods. According to at least certain embodiments, the invention includes novel, improved or modified microporous membranes, or membranes, fibers, microporous fibers, materials or layers, and textiles, such as woven, nonwoven, knit, bonded, flocked, and / or other textiles, laminates, laminates, composites, garments, etc., made from such fibers or membranes, and such microporous membranes or porous fibers include one or more copolymers, such as copolymers or impact copolymers, preferably comprising two or more polyolefins, such as copolymers or impact copolymers, preferably blended with one or more copolymers, such as copolymers or impact copolymers, preferably comprising two or more polyolefins. According to at least certain embodiments, the present invention comprises new, improved or modified microporous membranes or membranes, fibers or microporous fibers that have been blended with one or more block copolymers or impact copolymers as a means to improve the characteristics, performance and / or properties of such membranes, fibers or porous fibers, such as the hand, quietness and / or surface coefficient of friction of the membranes, fibers, materials, layers or fabrics, such as microporous polyolefin membranes and / or fabrics or polyolefin fibers for or in textile end uses.

[0008] Conventional methods for modifying the hand, flexibility and surface friction coefficient of polyolefin films generally involve coatings that are difficult to adhere to and risk the coating being easily changed.The approach of the present invention using block copolymers of two or more polyolefins, or using a mixture or blend of polyolefins and one or more block copolymers, provides a durable method to produce a range of different textile materials with improved properties, such as desirable hand, flexibility and low surface friction coefficient, for use in many textile applications that require water resistance and permeability performance, such as outerwear, disposable clothing, durable clothing, textile materials that require relative humidity assimilation, and / or medical related applications.

[0009] Microporous polyolefin membranes or coatings can be produced by several methods, including the dry stretch method (also known as the Celgard dry stretch method) used by Celgard, Inc., Charlotte, North Carolina, and a wet method known as the phase separation method or extraction method used by Celgard Korea, Inc., South Korea, and Tonen, Inc., Japan. Microporous membranes produced by these methods are produced by these methods with polyolefins, such as, but not limited to, polypropylene, polyethylene, poly-1-butene, poly-4-methyl-1-pentene, and / or blends, mixtures, or combinations thereof. The selection of the polyolefin or polyolefins can affect the performance properties of the membrane for a particular end use. Polyolefins (PO) can be homopolymers or copolymers of composition. A homopolymer consists of one polymer, while a copolymer consists of two or more polymers arranged in a distribution of lengths to various sequences. For example, in the case of a copolymer, monomer A can be copolymerized with monomer B to form a block copolymer AA / BB / AA / BB having blocks of repeating polymerization units AA and BB. This is only one example of the many possible sequences of A and B polymerized units that can form a block copolymer (BCP) or impact copolymer (ICP). In addition, according to the present invention, the composition, length, amount, sequence and sequence of the block copolymer moieties AA / BB or AAAA / BBBB can affect the performance properties of the final textile product, such as hand, flexibility, motion quietness, surface friction coefficient, of the microporous structure PO / ICP, PO / BCP, ICP or BCP membrane and fiber. The term "block copolymer" is a type of copolymer or impact copolymer, with other well-known copolymers being random or graft copolymers.

[0010] The method of variation of the present invention can be preferred to be cost effective and easy to control to facilitate custom tailoring of performance characteristics such as hand, flexibility, quietness in motion, and bottom surface coefficient of friction for use in specific textile garments and textile related end use applications. According to at least selected embodiments, the microporous membranes of the present invention can be produced by dry stretching, in which a polyolefin-based resin is extruded by blown film or cast film to produce a non-porous precursor film, which is then cold or hot stretched in the machine direction (uniaxially) to form a microporous membrane having a final thickness of less than 75 μm, preferably about 12-25 μm (although it may be thinner or thicker depending on the end use). According to at least certain embodiments of the membranes of the present invention, the polyolefin resin can be one or more block copolymers (BCP) or impact copolymers (ICP), preferably made of polypropylene and polyethylene, respectively. Alternatively, the polyolefin-based resin can be extruded by blown film or cast film to produce a non-porous precursor film, which is then stretched in the machine and transverse directions (biaxially) to form a microporous membrane having a final thickness of preferably about 12-25 μm to less than 75 μm.

[0011] According to a further embodiment, one or more impact copolymers, preferably consisting of polypropylene and polyethylene, are extruded by a blown film or cast film process and then cold or hot stretched in the machine direction (MD) and then sequentially stretched in the transverse direction (TD) (with simultaneous machine direction relaxation) to form a biaxially stretched or biaxially set (BO) microporous membrane according to the method described in U.S. Pat. No. 2011 / 0223486, incorporated herein by reference.

[0012] According to a further embodiment, one or more impact copolymers, preferably consisting of polypropylene and polyethylene, are extruded by blown film or cast film process, and then cold or hot stretched first in the machine direction and then stretched in the transverse direction to form a biaxially stretched or biaxially attached (BO) microporous membrane, as described in US2011 / 0223486, where the biaxial stretching step does not include simultaneous machine direction relaxation.

[0013] According to certain further embodiments, a polypropylene-based (PP) block copolymer (BCP) having a polypropylene content of 90-97% can be synthesized with a beta-nucleating (BN) agent and extruded using a casting method to form a non-porous beta-nucleated polypropylene-based BCP precursor film. Biaxial stretching of the beta-nucleated polypropylene precursor film ruptures the boundary between the beta-nucleated regions of PP and the alpha-nucleated regions of PP. This rupture process produces a microporous film having a thickness of less than 75 μm, preferably about 12-25 μm, by forming holes in the beta-nucleated biaxially bound polypropylene (BN-BOPP) film.

[0014] In a further embodiment of the membrane comprising a polyolefin blended with one or more impact or block copolymers of the present invention, the polyolefin blended with one or more impact or block copolymers is extruded by a blow-coating process to form a non-porous precursor, which is then cold and hot stretched in the machine direction (uniaxially) to form a microporous membrane or coating.

[0015] According to further embodiments, polyolefins (PO) blended with one or more impact copolymers (ICPs) are extruded by blown film or stretched by blown or cast film to form a non-porous precursor membrane, which is cold and hot stretched in the machine direction (MD) and subsequently stretched in the transverse direction to form a biaxially stretched or biaxially oriented (BO) microporous membrane by the stretching method described in US2011 / 0223486. BO) Including a simultaneous longitudinal relaxation step to produce a microporous membrane.

[0016] According to a further embodiment, polyolefin (PO) blended with one or more impact copolymers (ICP) is extruded by blown film process or stretched by cast film process to form a non-porous precursor membrane, which is stretched cold and hot in machine direction (MD) and subsequently in transverse direction to form a biaxially stretched or biaxially oriented (BO) microporous membrane by the stretching method described in US2011 / 0223486. The transverse stretching step does not include a simultaneous machine direction relaxation step to produce a biaxially oriented (BO) microporous membrane.

[0017] According to certain further embodiments, a polyolefin (PO) blended with one or more impact copolymers (ICPs), the ICPs being predominantly polypropylene-based (PP) ICP copolymers having a PP content of 90-97%, can be synthesized with a β-nucleating (BN) agent and extruded using a cast film process to form a non-porous β-nucleating PO / ICP precursor. Biaxial extrusion of the β-nucleating polypropylene precursor type film ruptures the boundaries that exist between the β-nucleating PP domains and the α-nucleating PP domains. This rupture process produces a microporous film having a thickness of less than 75 μm, preferably about 12-25 μm, by forming holes in the β-nucleating biaxially bonded polypropylene (BN-BOPP) film.

[0018] According to selected embodiments, the present invention relates to novel or modified coatings, fibers or hollow fibers (or materials, layers, fabrics, composites or laminates made therefrom) comprising 1) one or more block or impact copolymers (BCPs or ICPs) or 2) a polyolefin microporous membrane blended with one or more BCPs or ICPs. The choice of using one or more block or impact copolymers or using a polyolefin blended with one or more block or impact copolymers provides a method to create a range of differentiated textile materials with improved performance properties such as hand, flexibility and surface friction coefficients that are desirable for a variety of textile end uses that may also require waterproof and permeability performance, e.g., outerwear, disposable garments, durable garments, textiles requiring relative humidity equalization, or articles for material medical related applications. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 shows examples of block or impact copolymers composed of blocks of different polymerized monomers. [Diagram 2] 11A-11C are SEM images of the respective surfaces of the product of Example 5 at different magnifications. [Diagram 3] 11A-11C are SEM images of the respective surfaces of the product of Example 5 at different magnifications. [Figure 4] 11A-11C are SEM images of the respective surfaces of the product of Example 5 at different magnifications. [Diagram 5] 11A-11C are SEM images of the respective surfaces of the product of Example 5 at different magnifications. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] According to at least selected embodiments, the invention relates to new, improved or modified porous membranes, fibers, porous fibres, products made from such membranes or fibres and / or associated methods of manufacture (use), etc. According to at least certain embodiments, the invention relates to new, improved or modified microporous membranes, coatings, fibres, microporous fibres, hollow fibres, materials or layers made from such membranes or fibres for use in textile materials, garments, products and / or textile related applications. According to at least certain selected embodiments, the invention relates to new, improved or modified microporous membranes, fibres or microporous fibres, e.g. rigid or hollow fibres, microporous hollow fibres, shaped fibres, materials, layers or fabrics made from such fibres or membranes, which membranes, fibres, coatings or fibres are preferably made from polymers, e.g. one or more copolymers comprising two or more polyolefins, e.g. block copolymers or impact copolymers. According to at least certain embodiments, the present invention relates to novel, improved or modified microporous membranes, comprising polyolefins blended with one or more block or impact copolymers, to improve the composition, characteristics, performance and / or properties of membranes, fibers, materials, layers or textiles made from such membranes or fibers, and to improve the characteristics, performance and / or properties of membranes, fibers, materials, layers or textiles, e.g., the hand, flexibility, quietness and / or surface friction coefficient of the membranes, fibers, materials, layers or textiles, e.g., microporous polyolefin membranes and / or polyolefin fibers for textile end products. According to at least certain selected embodiments, the present invention relates to novel, improved or modified polyolefin materials or compositions, comprising one or more block or impact copolymers blended or mixed with one or more polyolefins. Additionally, according to at least certain embodiments, the present invention relates to new, improved or modified polyolefin materials or compositions in which one or more polyolefins are blended or mixed into one or more block or impact copolymers, which blends or mixtures affect the hand, flexibility, quietness, and / or low surface coefficient of friction properties of the microporous polyolefin membranes, blends or mixtures made from such polyolefin materials or compositions.

[0021] According to at least selected embodiments, the present invention relates to new, improved, or modified microporous membranes, fibers, or microporous fibers (or layers, materials, compositions, laminates, or fabrics produced therefrom) for use in textile garments, textile materials, or textile related applications. According to at least certain embodiments, the present invention relates to new, improved, or modified microporous membranes, fibers, porous fibers, or hollow fibers comprising one or more impact or block copolymers (abbreviated herein as BCPs or ICPs), preferably polyolefins including polypropylene and polyethylene or polyolefins mixed or blended with one or more impact or block copolymers. FIG. 1 is a schematic diagram of possible copolymer block repeat units consisting of monomer A (labeled as "A" in FIG. 1) and monomer B (labeled as "B" in FIG. 1), preferably propylene and ethylene monomers, and ethylene monomers. Preferably, the block or impact copolymers (BCPs or ICPs) are made of two or more monomer types (e.g., propylene and ethylene monomers).

[0022] According to at least certain embodiments, the present invention relates to new, improved or modified microporous membranes, fibers, porous fibers or hollow fibers comprising one or more block polymers (BCPs) comprising polypropylene and polyethylene, preferably present in a mole fraction of 1% to 50%, and more preferably present in a mole fraction of 3% to 10%.

[0023] In another embodiment, the present invention relates to a new, improved or modified microporous membrane, coating, fiber, porous fiber, hollow fiber comprising a polyolefin (PO) blended with one or more impact copolymers (ICPs). The one or more impact copolymers preferably comprise polyolefins such as, but not limited to, polypropylene, polyethylene, poly-1-butene, poly-4-methyl-1-pentene, polyhexene, polyoctene and / or mixtures or combinations thereof. When a polyolefin is blended with one or more impact copolymers, the length, amount, arrangement and sequence of the PO / ICP polymers or sections in the modified microporous membrane of the present invention provide a method for designing modified microporous membranes, membranes, fibers or hollow fibers with targeted enhanced performance properties for textile related end products. The mole fraction composition of polypropylene and polyethylene present in the ICP or BCP sections or in the PO / ICP or PO / BCP polymerized microporous membranes can vary and is preferably between 1% to 50%, more preferably between 3% to 10%. In the chemical structure of the polymer blend, blend, or composition of the modified microporous membrane of the present invention Varying the composition, length, order, amount and sequence of BCP or ICP segments, or PO / ICP or PO / BCP polymers in the polymer backbone affects film or product properties such as hand feel, suppleness, quiet movement and coefficient of friction resulting in microporous polyolefin films with soft suppleness, quiet movement and low surface friction coefficient that provide, for example, a silk-like feel.

[0024] In at least selected embodiments, the invention relates to new, improved, or modified microporous membranes, coatings, fibers, or hollow fibers, materials, or layers made from such membranes, fibers, hollow fibers, etc., fibers, or hollow fibers for textile materials, garments, products, and / or textile related applications. According to at least certain embodiments, the invention relates to new, improved, or modified microporous membranes or coatings, fibers, or microporous fibers, e.g., rigid or hollow fibers, microporous hollow fibers, shaped fibers, materials, layers, or textiles made from such fibers or membranes, including woven, nonwoven, knit, bonded, flocked, and / or other textiles, laminates, composites, garments. These membranes, fibers, or hollow fibers are preferably made from one or more copolymers, e.g., block copolymers, preferably comprising or made from two or more polyolefin monomers, or one or more polymers, including impact polymers. Such membranes, fibers or hollow fibers are preferably made from one or more copolymers comprising two or more polyolefins, e.g., block copolymers or polymers preferably consisting of one or more polyolefins together with impact copolymers. According to at least a specific embodiment, the present invention relates to novel, improved or modified microporous membranes or coatings, fibers or microporous fibers in which polyolefins are compounded or blended with one or more block copolymers or impact polymers to improve the hand, flexibility, quietness and / or surface friction coefficient of the membrane, fiber, material, layer or fabric, e.g., microporous polyolefin membranes and / or polyolefin fibers for fabric or textile end products, as a means to improve the composition, characteristics, performance and / or properties of the membrane, fiber, material, layer or fabric made from such membranes, fibers or hollow fibers.

[0025] Microporous polyolefin membranes can be produced by several methods, for example, from thermoplastic polymers including polyolefins, such as polypropylene, polyethylene, poly-1-butene, poly-4-methyl-1-pentene, and / or polyolefin blends, mixtures, or combinations thereof. The choice of polyolefin affects the performance properties of the membrane in a given end use. The composition, length, sequence, amount, and arrangement of the copolymers or block copolymers affect the performance properties of hand, flexibility, motion quietness, and surface friction coefficient in microporous polyolefin membranes and / or fibers for textiles or end uses. The mole fraction of polypropylene and polyethylene present in the membrane or fiber of the present invention, in the BCP or ICP, or in the ICP or BCP portion of the PO / ICP or PO / BCP polymerized microporous membrane, can vary, preferably between 1% and 50%, more preferably between 3% and 10%.

[0026] According to at least selected embodiments, the microporous membranes of the invention can be made by a dry stretch process in which a polyolefin resin is extruded using a blown film or molded film process, and then cold and / or hot stretched in the machine direction to form a microporous membrane having a final thickness, typically less than 75 μm, and preferably about 12-25 μm. According to at least certain embodiments of the present membrane, the polyolefin resin can be an impact copolymer (ICP) or block copolymer (BCP), preferably made of polypropylene and polyethylene. The ICP or BCP can be extruded by a blown film or molded film process to form a microporous membrane, and then cold or hot extruded in the machine direction (uniaxially) to form a microporous membrane having a final thickness, typically less than 75 μm, and preferably about 12-25 μm.

[0027] According to a further embodiment, one or more copolymer ICPs, one or more of which preferably comprises polypropylene and polyethylene in a molar fraction between 1% and 50%, more preferably between 3% and 10%, are stretched using a blown film process or using a cast film process to form a solid precursor membrane, which is then cold and hot stretched first in the machine direction and subsequently in the transverse direction (TD) to form a biaxially stretched or biaxially oriented microporous membrane according to the method described in US 2011 / 0223486. The transverse stretching step includes a simultaneous machine direction relaxation step to produce a biaxially oriented (BO) microporous membrane having a final thickness typically less than 75 μm, preferably 20-40 μm, more preferably 15-30 μm, and most preferably 8-20 μm.

[0028] According to a further embodiment, one or more impact copolymers (ICPs) comprising polypropylene and polyethylene, preferably in mole fractions of 1% to 50%, more preferably 3% to 10%, are stretched using blown or cast film techniques to form a microporous membrane, which is then cold or hot infiltrated and stretched first in the machine direction and then in the transverse direction (TD) to form a biaxially stretched or biaxial (BO) microporous membrane according to the method described in U.S. Patent Publication 2011 / 0223486. The transverse stretching step does not include a simultaneous machine direction relaxation step, and produces a biaxial (BO) microporous membrane having a final thickness typically less than 75 μm, preferably 10 to 40 μm, more preferably 15 to 30 μm, and most preferably 8 to 20 μm.

[0029] According to a further specific embodiment, a polypropylene-based impact copolymer (ICP) containing 90-97% polypropylene is synthesized using a β-nucleating (BN) agent and stretched using a cast film method to form a solid β-nucleated polypropylene-based ICP precursor film having a thickness of less than 300 μm, preferably less than 150 μm. Polypropylene is a multiphasic anticrystalline polymer that can crystallize in α and β crystalline forms with different densities.

[0030] The β-nucleating agent converts the polypropylene from the more common α-crystalline state to the less common β-crystalline state when the polypropylene is stretched and directed against rollers maintained at a controlled temperature specifically selected to optimize β-crystal growth. Biaxial stretching of the β-nucleated polypropylene-based ICP precursor film ruptures the boundaries between the β-nucleated PP domains and the α-nucleated PP domains. The rupture process at the boundaries between the β-nucleated PP domains and the α-nucleated PP domains creates micropores, resulting in a β-nucleated biaxially oriented polypropylene (BN-BOPP) film having a thickness of less than 75 μm, preferably 12-25 μm.

[0031] In further embodiments, membranes comprising polyolefins (PO) combined with one or more impact copolymers (ICPs) are extruded using blown film techniques or cast film techniques to form a solid precursor thin film, which is then cold and hot stretched in the machine direction (uniaxially) to form a microporous membrane having a final thickness, typically less than 75 μm, preferably about 12-25 μm.

[0032] According to a further embodiment, the membranes of the invention comprising polyolefins compounded with one or more impact copolymers are extruded using a blown film process or using a cast film process to form a solid precursor thin film, which is then cold and hot stretched in the machine direction and subsequently stretched in the transverse direction to form a biaxially oriented (BO) microporous membrane in the manner described in U.S. Patent Publication No. 2011 / 0223486. The transverse stretching process includes a simultaneous machine direction relaxation process to produce a biaxially oriented (BO) microporous membrane having a final thickness typically less than 75 μm, preferably 10-40 μm, more preferably 15-30 μm, and most preferably 8-20 μm.

[0033] According to a further embodiment, the membranes of the invention comprising polyolefins compounded with one or more impact copolymers are extruded using a blown film process or using a cast film process to form a solid precursor thin film, which is then cold and hot stretched in the machine direction and subsequently stretched in the transverse direction to form a biaxially oriented (BO) microporous membrane in the manner described in U.S. Patent Publication No. 2011 / 0223486. The transverse stretching process does not include a simultaneous machine direction relaxation process, and produces a biaxially oriented (BO) microporous membrane having a final thickness typically less than 75 μm, preferably 10-40 μm, more preferably 15-30 μm, and most preferably 8-20 μm.

[0034] According to a further specific embodiment, a polyolefin (PO) compounded with one or more impact polymers (ICPs) (or BCPs), where the ICPs are polypropylene-based ICP polymers containing 90-97% PP, is synthesized using a beta-nucleating (BN) agent and stretched using a cast film method to form a solid beta-nucleated PO / BCP precursor film less than 300 μm thick. Polypropylene is a multiphasic anticrystalline polymer that can crystallize in α and β crystalline forms with different densities. The β nucleating agent converts the polypropylene from the more common α crystalline state to the less common β crystalline state when the polypropylene is stretched and directed against rollers that are maintained at a controlled temperature specifically selected to optimize β crystal growth. Biaxial stretching of the β-core polypropylene-based ICP precursor film ruptures the boundaries between the β-core PP domains and the α-core PP domains. The rupture process at the boundaries between the β-core PP domains and the α-core PP domains creates micropores, resulting in a β-core biaxially oriented polypropylene (BN-BOPP) film with a thickness of less than 75 μm, preferably 12-25 μm.

[0035] According to at least selected embodiments, the present invention relates to novel or modified microporous membranes, fibers, hollow fibers, or microporous hollow fibers that include 1) an impact copolymer (ICP) (or BCP) made of two or more polyolefins, or 2) a polyolefin compounded with an impact polymer (ICP) (or BCP) made of two or more polyolefins. The choice of using an impact copolymer (ICP) or a polyolefin compounded with one or more impact copolymers (ICPs) provides a way to produce a range of different textile materials with improved performance properties, such as more desirable hand, flexibility, and surface friction coefficient for many textile end products requiring water resistance and freshness, such as outerwear, disposable garments, durable garments, textile materials requiring relative humidity equivalence, and garments / articles for medical related applications. It will be understood that many other variations and modifications of the present invention are possible to those skilled in the art of the teachings herein, and therefore, within the scope of the appended claims, the present invention may be practiced other than as specifically described herein. EXAMPLES

[0036] Example 1 The impact copolymer polyolefin resin is melt extruded to form a solid precursor membrane having a thickness of 25 μm. The solid precursor membrane is then uniaxially stretched in the machine direction (MD) to produce a microporous coating having a thickness of 20.8 μm and a JIS Gurley value of 1354 seconds. Table 1 lists the properties of the microporous coating of Example 1.

[0037] [Table 1]

[0038] Example 2 The uniaxially stretched microporous membrane produced in Example 1 was biaxially stretched in the transverse direction (TD) without relaxation in the machine direction (MD) by the same method as described in Example 1. The TD stretched membrane was stretched in the TD direction 2 to 4 times its input width. The resulting microporous membrane had a JIS Gurley value of <100, which is an acceptable level of breathability to function as a breathable woven membrane.

[0039] Example 3 It was biaxially stretched in the transverse direction (TD) as described in US Patent Publication 2011 / 0223486 with simultaneous relaxation in the machine direction by the same method as described in Example 1. A TD stretch of 4.5x, MD relaxation of 0-16% produced a microporous membrane with a thickness of 10.9 μm and a JIS Gurley value = 73 seconds. Table 2 lists the physical properties of the microporous coating of the present invention.

[0040] [Table 2]

[0041] Example 4 The impact copolymer polyolefin resin is melt extruded to form a 35 μm thick solid precursor membrane 35. The solid precursor membrane is then biaxially stretched in the machine direction (MD) to produce a microporous coating having a thickness of 26 μm and a JIS Gurley value of 3454 seconds. Table 3 lists the properties of the microporous coating of Example 4.

[0042] [Table 3]

[0043] Example 5 In a manner similar to that described in Example 4, a uniaxially stretched 26 μm thick microporous membrane prepared as in Example 3 was biaxially stretched in the transverse direction (TD) with a simultaneous longitudinal relaxation step as described in U.S. Patent Publication 2011 / 0223486. A 4.5× TD stretch and 0-16% total MD relaxation resulted in a 19 μm thick and JIS A microporous membrane was produced with a Gurley value of 25 seconds.

[0044] [Table 4]

[0045] (Test Method) Gurley is defined as the Japanese Industrial Standard (JIS Gurley) and is measured using an OHKEN Permeability Tester. JIS Gurley is defined as the time in seconds required for 100cc of air to pass through 1 square inch of membrane at a constant water pressure of 4.9 inches. Thickness is measured in μm using an Emveco Microgage 210-A micrometer thickness tester and ASTM D374 test procedure.

[0046] Machine direction (MD) and transverse direction (TD) tensile stresses are measured using an Instron Model 4201 according to ASTM-882 procedures. % MD elongation at break is the percentage of elongation of the specimen along the machine direction of the specimen measured at the maximum tensile stress required to break the specimen. % TD elongation at break is the percentage of elongation of the specimen along the transverse direction of the specimen measured at the maximum tensile stress required to break the specimen.

[0047] The breaking stress is measured according to ASTM D3763 using an Instron Model 4442. Measurements are taken across the width of the microporous membrane and the breaking stress is defined as the force required to break the specimen. Basis weight is the weight per unit area of ​​a material and can be expressed in grams per meter squared. It is the weight in grams of a test sample of a known area in meters squared.

[0048] The % shrinkage is measured by placing the specimen in a 90° C. oven for 1 hour. is measured in the machine direction (MD) and in the transverse direction (TD). When polyolefins are combined with one or more impact or block copolymers, the length, amount, sequence and order of the polyolefin and impact polymer in the chemical structure of the polymeric structure of the modified microporous membrane of the present invention can be adjusted to achieve the targeted reinforced and viscoelastic properties in the textile related end product. Methods are provided for designing coatings, fibers, porous fibers or hollow fibers with performance.

[0049] Certain microporous membranes are highly hydrophobic and exceptionally breathable, making them ideal as barrier layers in waterproof / breathable textiles, such as high performance outerwear. Historically, in the development of such polyolefin coatings, raw polymers were selected that, among other factors, were intended to produce a physically strong coating. This resulted in a stiff coating that tended to crimp, and did not provide the ideal hand (i.e., feel) of the material. In accordance with the present invention, one way to improve the hand of such PO films is to use a polypropylene / polyethylene block copolymer resin.

[0050] PP / PE block copolymers are available from various resin manufacturers. With block copolymers with at least a low content of PE (preferably less than 5%), the resulting coating is less stiff and therefore more pliable, quieter in motion, has a lower coefficient of friction, and feels more silky. This type of block polymer coating also appears to be suitable for TD elongation, making 60 inch (or wider) wide porous coatings for textile applications.

[0051] According to one embodiment, a microporous membrane, such as a polyolefin microporous membrane, is laminated to a hollow polymeric nonwoven material or mesh, such as a polyolefin nonwoven, and then microcreped. By way of certain other non-limiting examples, selected possible products, laminates, combinations, embodiments, or examples that utilize the porous membranes or fibrous layers of the present invention are listed.

[0052] 1) Porous membrane or fiber layer according to an embodiment of the present invention + PE or PP nonwoven fabric 2) Composite fabric + porous membrane or fiber according to an embodiment of the present invention + PE or PP nonwoven inner layer 3) PE or PP nonwoven + porous membrane or fiber layer according to an embodiment of the present invention + PE or PP nonwoven 4) Composite fabric + porous membrane or fiber according to an embodiment of the present invention + woven inner layer 5) Composite fabric + 2 layers of porous membrane or fiber layer according to an embodiment of the present invention + woven fabric inner layer

[0053] 6) Composite fabric + PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention + woven fabric inner layer 7) Composite fabric + porous membrane or fiber layer of an embodiment of the invention; 8) Porous membrane or fiber layer according to an embodiment of the present invention + adhesive + PE or PP nonwoven fabric 9) Composite fabric + adhesive + porous membrane or fiber layer + PE or PP nonwoven inner layer 10) Composite fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + PE or PP nonwoven inner layer

[0054] 11) Composite fabric + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + PE or PP nonwoven inner layer 12) PE or PP nonwoven fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention + PE or PP nonwoven fabric 13) PE or PP nonwoven fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + PE or PP nonwoven fabric 14) PE or PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + PE or PP nonwoven fabric 15) Composite fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention + woven inner layer

[0055] 16) Composite fabric + porous membrane or fiber layer of an embodiment of the invention + adhesive + woven inner layer 17) Composite fabric + adhesive + porous membrane or fiber layer of an embodiment of the invention + adhesive + woven inner layer 18) Two layers of composite fabric + porous membrane or fiber layer according to an embodiment of the present invention 19) Two layers of composite fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention 20) Composite fabric + adhesive + two layers of porous membrane or fiber layer + woven inner layer

[0056] 21) Composite fabric + 2 layers of porous membrane or fiber layer according to the embodiment of the present invention + woven fabric inner layer 22) Composite fabric + adhesive + two layers of a porous membrane or fiber layer according to an embodiment of the present invention + adhesive + woven inner layer 23) Composite fabric + adhesive + porous membrane or fiber layer of an embodiment of the present invention + adhesive + porous membrane or fiber layer + adhesive + woven inner layer 24) Composite fabric + adhesive + PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention 25) Composite fabric + adhesive + PP nonwoven fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention

[0057] 26) Composite fabric + PP nonwoven fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention 27) Composite fabric + adhesive + PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention + woven inner layer 28) Composite fabric + PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + woven inner layer 29) Composite fabric + adhesive + PP nonwoven fabric + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + woven inner layer 30) Composite fabric + adhesive + PP nonwoven fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention + adhesive + woven inner layer 31) Composite fabric + adhesive + porous membrane or fiber layer according to an embodiment of the present invention

[0058] According to at least selected embodiments, the present invention relates to new, improved or modified porous membranes, fibers, products and / or related methods. According to at least certain embodiments, the present invention relates to new, improved or modified microporous membranes, fibers, etc. for use in textile materials, garments, products and / or textile related applications. According to at least certain selected embodiments, the present invention relates to new, improved or modified microporous membranes, fibers, porous fibers comprising copolymers, such as impact copolymers comprising two or more polyolefins. According to at least certain embodiments, the present invention relates to new, improved or modified microporous membranes, fibers, porous fibers, or hollow fibers comprising polyolefins in combination with one or more impact copolymers as a means of improving the composition, characteristics, performance and properties of materials or textiles, such as the hand, flexibility of microporous polyolefin membranes and / or fibers for textile end products. Additionally, the polyolefin may be blended or mixed with one or more impact polymers, and the length, amount, sequence and order of the polyolefin and / or impact copolymer in the blended polymer chemical structure of the modified microporous membranes and fibers of the present invention affect the performance properties of hand, flexibility, quietness of motion, and / or surface coefficient of friction of the microporous membrane and / or fiber for textile products and / or end products.

[0059] Preferred inventive laminate or composite microporous membranes are further modified, treated or altered using coating or microcreping techniques that introduce permanently small, regularly spaced crepes, profiles, compacts, pleats or wrinkles into the laminate or composite microporous membrane for the purpose of improving mechanical strength, modulus and / or resiliency. In addition, the microcreped microporous membranes of the present invention embodiments have improved hand feel or softness, improved skin-like softness, and / or quietness during movement, which may be a desired performance characteristic or feature of a textile garment, material or application.

[0060] In accordance with at least selected embodiments, objects or aspects of the present invention, a textile material, a garment, As a means to improve the composition, characteristics, performance and properties of new, improved or modified microporous membranes, fibers, etc., materials or fabrics used in products and / or textile related applications, e.g., the hand and suppleness of microporous polyolefin membranes and / or fabrics for textile end products, there is provided a new, improved or modified microporous membrane or coating, fiber, porous fiber, or hollow fiber (product, layer, composite, laminate, material, fabric, made therefrom) comprising a copolymer, e.g., an impact polymer comprising two or more olefins, wherein the polyolefin is blended or mixed with one or more impact polymers, and the blending or blending affects the hand, suppleness, quietness of motion, and / or surface coefficient of friction performance properties of the microporous membrane and / or fabric for textile end products.

[0061] In at least one embodiment, the microporous membrane, fiber, etc., as a means of improving the composition, characteristics, performance and properties of the material or textile, e.g., the hand, flexibility of the microporous polyolefin membrane and / or fiber for textile end products, the microporous membrane, fiber and / or microporous fiber is blended with at least one polyolefin copolymer. The polymer may be made of one or more copolymers, such as block or impact copolymers.

[0062] In accordance with at least selected embodiments, objects or aspects of the invention, the present invention provides new, improved or modified microporous membranes, fibers, microporous fibers, products made from such membranes, fibers or microporous membranes, and / or related methods of manufacture, uses, etc. Microporous membranes or coverings, fibers or microporous fibers, e.g., rigid or hollow fibers, shaped fibers, materials, layers or fabrics, including microporous membranes, fibers, microporous fibers, materials or layers made from such membranes, fibers or microporous membranes, woven, nonwoven, knit, bonded, flocked and / or other textiles, laminates, composites, garments, used in textile materials, apparel, products, and / or textile related products, where such membranes, fibers or porous fibers comprise a polymer, one or more copolymers, e.g., block copolymers or impact copolymers, preferably comprising two or more polyolefin monomers, or where such membranes, fibers or porous fibers comprise one or more copolymers, e.g., block copolymers or impact copolymers, preferably comprising two or more polyolefin monomers. Microporous membranes or coatings, fibers, microporous fibers, hollow fibers, microporous fibers comprising polyolefins blended or blended with one or more block or impact copolymers as a means of improving the composition, characteristics, performance and properties, e.g., hand, flexibility, quietness of motion, and / or surface friction performance properties of the membranes, fibers, materials, layers, or fabrics, e.g., microporous polyolefins and / or polyolefin fibers for textile end products, comprising one or more polyolefins together with a copolymer, to improve the composition, characteristics, performance and properties, e.g., hand, flexibility, quietness of motion, and / or surface friction coefficient of the membranes, fibers, materials, layers, or fabrics, e.g., microporous polyolefins and / or polyolefin fibers for textile end products.

[0063] According to selected embodiments or examples, the present invention relates to new or improved membranes, new or improved porous membrane fabrics, new or improved microporous membranes, and / or methods of manufacture, marketing, and / or use thereof. The present invention relates to microporous membrane fabrics, new or improved methods for use in blotting oil from a person's face, and / or for use in removing fingerprints, smudges, and the like from eyeglasses, electronic products, cell phones, displays, optical instruments, camera lenses, microscope lenses, and other precision lenses, and the like. In at least selected embodiments, the microporous membrane fabric relates to a microporous membrane made of polyethylene and / or polypropylene impact polymers. In at least other embodiments, the microporous membrane fabric can be a biaxially microporous membrane made of polyethylene and / or polypropylene impact polymers.

[0064] In another embodiment, the microporous membrane fabric of the present invention can be used for surface cleaning, such as, but not limited to, oil, fingerprints, dirt, etc., on glasses, electronic products, mobile phones, displays, optical instruments, camera lenses, microscope lenses and other precision lenses. The preferred features of the microporous membrane fabric of the present invention used for surface cleaning are, but not limited to, the following: designed for elegant processing, clean nap fabric, no wear, good touch, absorbs oil without leaving oil on hands, provides visibility of absorbed oil, antistatic adjustment. It has been found that the microporous membrane fabric of the present invention works very well as a lint-free cloth for optical instruments and other technical needs. Fingerprints, dirt, etc. on display screens, glasses and similar surfaces are widely oil-based. Therefore, the microporous membrane fabric of the present invention works particularly well as a cloth for these surfaces due to its oil absorption properties. Other advantages of the microporous membrane fabric are that it is very soft to the touch and has high porosity, thus enhancing the absorption properties. Kimwipes® are typically used in the microporous membrane fabrics of the present invention, and in particular in place of microfiber cleaning cloths, biaxially oriented impact copolymer membrane fabrics are also used in consumer products such as cleanroom fabrics, precision optical equipment fabrics, and disposable eyeglass fabrics.

[0065] In one embodiment, the microporous membrane fabric of the present invention is biaxially stretched, as disclosed, for example, in U.S. Patent Publications 20070196638 and 20110223486, each of which is incorporated herein by reference. Such biaxially oriented membranes may be biaxially oriented Celgard membranes. The biaxial orientation of the membrane increases the porosity of the membrane. Since the uniaxial orientation of the Celgard film increases, it can function better as a skin oil blotting paper than the uniaxial Celgard film. Additionally, biaxially oriented Celgard membranes are manufactured from copolymers of polyethylene and pure polypropylene. The hand of the membrane is significantly superior to that of both the Celgarad membrane made from Celgarad cellulose and commercially available skin oil blotting papers. However, the present invention is not limited to the preferred biaxially oriented microporous membrane fabric, and any biaxially oriented microporous membrane fabric may be used as the microporous membrane fabric of the present invention.

[0066] In one embodiment, the microporous membrane fabric is produced by a dry stretching process, has holes with a generally round shape, and has a ratio of machine direction tensile strength to cross direction tensile strength in the range of 0.5 to 4.0. The microporous membrane fabric can be a thin, pliable, polymeric sheet, foil, or film having a plurality of holes therethrough. In a possibly preferred embodiment, the polymer used in the microporous membrane fabric of the present invention is an impact copolymer (PP with EPR). In other selected embodiments, the fabrics of the present invention may contain other ingredients, such as fillers (inert particles used to avoid fabric costs, but which do not significantly affect the fabric's manufacture or its physical properties), antistatic agents, antiblocking agents, antioxidants, lubricants (for ease of manufacture), and the like.

[0067] Example 6 The PP-based impact copolymer is extruded to form a thin film. The extrusion melt temperature is 249℃. The polymer melt is fed into an extrusion die set at 215°C. The extruded film has a thickness of 34 μm and a birefringence of 0.0116. The extruded precursor is then cooled at 154° C. for 2 min. The annealed film is then cold stretched at room temperature and stretched to 190% and relaxed to 41% at 140°C (total longitudinal stretches = 159%). The MD stretched film has a thickness of 26μ and a porosity of 40%. The MD stretched film is then stretched at 150°C, TD stretched to 260% and relaxed to 50%, followed by simultaneous MD and TD stretching at 150°C to 50% and 216%, respectively. Table 5 shows the experimental results of Example 6, which compares two commercially available dry stretched films: A) CELGAR® 2,400 (a single polypropylene cloth) and B) CELGARD (a three-layer polypropylene / polyethylene / polypropylene).

[0068] [Table 5]

[0069] In accordance with at least some embodiments of battery separators, there may be a need to further strengthen or enhance at least some battery separators, especially as the material becomes thinner. One way to obtain 1-10 μm material is by transverse direction (TD) stretching. Biaxial stretching can provide transverse strength that may be lost by uniaxial stretching. Battery separators are stretched in a biaxial manner, and the use of novel materials provides additional benefits The use of impact copolymers, either alone or in conjunction with other intact polyethylene materials, is extremely effective. In blended polymers, 1-80% impact polymer is preferred. The impact polymers, or copolymers, have a greater tensile strength than the porous stretched materials, typically 5-30%. It provides strength and elongation and offers a larger processing window.

[0070] The separators thus produced may be produced in a laminated tri-layer configuration and may be produced in a co-stretched or mono-stretched manner. These materials may be preferably coated with some type of polymer or ceramic coating prior to use in the battery. Many other modifications and / or variations of the present invention will occur to those skilled in the art of the technology described herein, and within the scope of the claims, other embodiments or examples may be devised and the invention may be practiced other than as specifically described herein.

Claims

1. comprising a mixture of at least one polyolefin and at least one block copolymer; the polyolefin is polypropylene, polyethylene, poly 1-butene, poly-4-methyl-1-pentene, polyhexene, polyoctene, and / or blends, mixtures, or combinations thereof; A microporous membrane, wherein the block copolymer comprises two or more monomers in a mole fraction ranging between 1% and 2%.

2. The microporous membrane of claim 1, wherein the microporous membrane has a thickness of 12 to 25 μm.

3. The microporous membrane of claim 1, wherein the microporous membrane has a thickness of 5 to 50 μm.

4. The microporous membrane of claim 1, wherein the polyolefin is polypropylene and / or polyethylene.

5. 10. The microporous membrane of claim 1, wherein the block copolymer comprises polypropylene and ethylene.

6. 10. The microporous membrane of claim 1, wherein the block copolymer is propylene and ethylene, and the propylene and / or ethylene is present in a mole fraction between 3% and 10%.

7. 2. The microporous membrane of claim 1, wherein the block copolymer comprises two or more monomers selected from propylene, ethylene, 1-butene, 4-methyl-1-pentene, hexene, aoctene, and / or blends, mixtures, or combinations thereof.

8. A microporous polyolefin membrane is included. The microporous membrane is a block copolymer comprising two or more polyolefins, or A textile material comprising a blend of a polyolefin and one or more block copolymers containing two or more monomers in mole fractions ranging from 1% to 50%.

9. The textile material of claim 8, wherein the microporous membrane has a thickness of 12 to 25 μm.

10. The textile material of claim 8, wherein the microporous membrane has a thickness of 5 to 50 μm.

11. 9. The fabric material of claim 8, wherein the block copolymer is propylene and ethylene, and the propylene and / or ethylene is present in a mole fraction between 3% and 10%.

12. 9. The textile material of claim 8, wherein the block copolymer comprises two or more monomers selected from propylene, ethylene, 1-butene, 4-methyl-1-pentene, hexene, aoctene, and / or blends, mixtures or combinations thereof.

Images