Abstract: The invention relates to microporous membranes having high meltdown temperature, high air permeability, and high puncture strength. The invention also relates to the production of such membranes and the use of such membranes as battery separator film.

Abstract: A microporous polyethylene membrane made of a polyethylene resin having a ratio (mass-average molecular weight/number-average molecular weight) of 5 to 300 and comprising 1% or more by mass of ultra-high-molecular-weight polyethylene having a mass-average molecular weight of 7×105 or more, the microporous polyethylene membrane comprising (a) a coarse-structure layer having an average pore diameter of more than 0.04 ?m, which is formed on at least one surface, and (b) a dense-structure layer having an average pore diameter of 0.04 ?m or less, an area ratio of the coarse-structure layer to the dense-structure layer in a membrane cross section being 0.1 to 0.8.

Abstract: A method of producing a microporous polyethylene film includes blending polyethylene and a membrane-forming solvent, stretching a sheet formed by extrusion through a die by stretching the sheet in the longitudinal direction at a stretching magnification of 1.1 to 2.0 and stretching the sheet simultaneously in the longitudinal direction and the width direction at an area magnification of 4 to 50, and removing the membrane-forming solvent.

Abstract: A microporous membrane comprising layers, wherein at least one layer comprises a first polymer having a Tm in the range of 115.0° C. to 130.0° C. and an Mw of from 5.0×103 to 4.0×105, and the membrane has a shutdown temperature?130.5° C. and a rupture temperature?170.0° C.

Abstract: The invention generally relates to polymer film, and more particularly relates to polymeric membranes, methods for producing such membranes, and the use of such membranes as battery separator film. In an embodiment, the invention relates to liquid-permeable multi-layer microporous membranes comprising microlayers. According to the invention, liquid-permeable multi-layer microporous membranes having excellent physical properties including permeability can be produced without causing delaminate.

Abstract: The present invention is a microporous membrane comprising polymethylpentene (a), polyethylene (b), and polypropylene (c), the microporous membrane having a meltdown temperature of 180° C. or higher, a TD heat shrinkage at 170° C. of 35% or less, and a thickness change ratio per thickness of 10% or less. An object of the present invention is to provide a microporous membrane having a high meltdown temperature, a low shutdown temperature, and resistance to heat shrinkage at high temperatures, which cannot be obtained by the prior art.

Abstract: A microporous membrane includes a low melting polypropylene, the low melting polypropylene being a polypropylene homopolymer or copolymer having an MFR?2.0×102, a Tm of 85.0° C. to 130.0° C., and a Te-Tm?10° C.

Abstract: A microporous polyethylene membrane made of a polyethylene resin comprising 15% or less by mass of ultra-high-molecular-weight polyethylene having a mass-average molecular weight of 1×106 or more, which is constituted by a dense-structure layer having an average pore diameter of 0.01 to 0.05 ?m, and a coarse-structure layer formed on at least one surface and having an average pore diameter 1.2-fold to 5.0-fold of that of the dense-structure layer, has a high electrolytic solution absorption speed with thickness and air permeability little changing when compressed. Such a microporous polyethylene membrane is produced by extruding a melt blend of the above polyethylene resin and a membrane-forming solvent through a die, cooling the resultant extrudate with a temperature distribution in a thickness direction to provide a gel-like sheet, stretching the gel-like sheet at a temperature from the crystal dispersion temperature of the polyethylene resin +10° C. to the crystal dispersion temperature +30° C.

Abstract: The invention relates to a multi-layer, microporous membrane having appropriate permeability, pin puncture strength, shutdown temperature, shutdown speed, meltdown temperature, and thickness uniformity. The invention also relates to a battery separator formed by such multi-layer, microporous membrane, and a battery comprising such a separator. Another aspect of the invention relates to a method for making the multi-layer, microporous polyolefin membrane, a method for making a battery using such a membrane as a separator, and a method for using such a battery.

Abstract: A method for plasma-treating a porous body, comprising the steps of generating plasma using an inert gas or a mixed gas of an inert gas and a reactive gas, (a) blowing the resultant plasma gas to the porous body at a flow rate per a unit area of the porous body of 0.002 to 2 L/minute/cm2, (b) sucking the porous body in a plasma gas atmosphere, or (c) sucking the porous body while blowing the plasma gas to the porous body at said flow rate, thereby treating the plasma the surfaces and pores of said porous body with plasma.

Abstract: The invention relates to microporous polymeric membranes suitable for use as battery separator film. The membrane comprises polyethylene, polypropylene, and polymethylpentene. The invention also relates to a method for producing such a membrane, batteries containing such membranes as battery separators, methods for making such batteries, and methods for using such batteries.

Abstract: Embodiments of the invention relate to microporous membranes that include first and second layers. The first layer includes ?20.0 wt. % polymethylpentene and the second layer includes a compatibilizer. The invention also relates to methods for making such membranes and the use of such membranes as battery separator film.

Abstract: The invention relates to microporous membranes having one or more layers comprising polymer and inorganic molecules. The invention also relates to methods for producing these membranes, and the use of these membranes as battery separator film.

Abstract: The present invention relates to microporous membranes comprising polymer and having well-balanced permeability and heat shrinkage, especially heat shrinkage at elevated temperature. The invention also relates to methods for making such membranes, and the use of such membranes as battery separator film in, e.g., lithium ion secondary batteries.

Abstract: Embodiments of the invention relate to microporous membranes that include first and second layers. The first layer includes ?20.0 wt. % polymethylpentene and the second layer includes a compatibilizer. The invention also relates to methods for making such membranes and the use of such membranes as battery separator film.

Abstract: The invention relates to microporous membranes having high meltdown temperature, high air permeability, and high puncture strength. The invention also relates to the production of such membranes and the use of such membranes as battery separator film.

Abstract: A thermoplastic film including a microporous polymeric membrane; and a non-woven web comprising a plurality of fibers, the web being bonded to the microporous polymeric membrane, wherein the fibers comprise oxidation-protective polymer having an MFR ?2.0×102.

Abstract: This invention relates to microporous membranes comprising polyolefin, the use of such membranes as battery separators, and methods for producing such microporous membranes. In particular, the invention relates to microporous membranes having a shutdown temperature in the range of 120.0° C. to 130.0° C. and a maximum solid state heat shrinkage ?30.0%.

Abstract: A microporous membrane comprising polyolefin copolymer, the membrane having a shutdown temperature?130.5° C. and a shutdown activation energy E2?3.5×103 J/mol.

Abstract: The invention relates to microporous membranes comprising polymer and having well-balanced permeability, shutdown temperature, and pin puncture strength. The invention also relates to methods for making such membranes, and the use of such membranes as battery separator film in, e.g., lithium ion secondary batteries.