Abstract: Disclosed is a microporous high density polyethylene film for a battery separator and a method of producing the same. The microporous high density polyethylene film includes high density polyethylene with a weight average molecular weight of 2×105?5×105, containing 5 wt % or less molecule with a molecular weight of 1×104 or less. The microporous high density polyethylene film has tensile strengths of 1,100 kg/cm2 or more in transverse and machine directions respectively, a puncture strength of 0.22 N/?m or more, a gas permeability (Darcy's permeability constant) of 1.3×10?5 Darcy or more, and shrinkages of 5% or less in machine and transverse directions, respectively. Particularly, the microporous high density polyethylene film has an excellent extrusion-compoundabiliy and stretchability and a high productivity, and can improve the performances and stability of a battery produced using the same.

Abstract: Disclosed is a microporous high density polyethylene film for a battery separator and a method of producing the same. The microporous high density polyethylene film includes high density polyethylene with a weight average molecular weight of 2×105-5×105, containing 5 wt % or less molecule with a molecular weight of 1×104 or less. The microporous high density polyethylene film has tensile strengths of 1,100 kg/cm2 or more in transverse and machine directions respectively, a puncture strength of 0.22 N/?m or more, a gas permeability (Darcy's permeability constant) of 1.3×10?5 Darcy or more, and shrinkages of 5% or less in machine and transverse directions, respectively. Particularly, the microporous high density polyethylene film has an excellent extrusion-compoundabiliy and stretchability and a high productivity, and can improve the performances and stability of a battery produced using the same.

Abstract: Disclosed in the present invention are a microporous polyethylene film and a method of manufacture thereof. The polyethylene microporous film manufactured according to the present invention may contribute to an increased productivity of stable products as its extrusion and stretching may be done readily. And thus manufactured product may be used for battery separators and various filters owing to its high gas permeability, superior puncture strength, and small ratio of shrinkage.

Abstract: The present invention discloses a microporous high-density polyethylene film for a battery separator, and process for preparing the same. The microporous high-density polyethylene film according to the present invention comprises of high-density polyethylene with weight average molecular weight of 2×105˜4×105, containing not more than 5 wt % of molecules with molecular weight of 1×104 or less and not more than 5 wt % of molecules with molecular weight of 1×106 or more, and has the properties of puncture strength of 0.22 N/?m or more, Darcy's permeability constant of 1.8×10?5 Darcy or more, and shrinkage of 4% or less in machine and transverse direction, respectively. Particularly, the microporous high-density polyethylene film has excellent extrusion-compoundability and stretchability with high productivity and enhances performances and stability of the battery using the film.

Abstract: The present invention is related to microporous polyolefin films that may be used for battery separators and the methods of manufacturing the same. These microporous polyolefin films are characterized by being manufactured in a method comprising the steps of melt-extruding a composition, comprised of 20-50 weight % of a resin composition, comprised of 90-98 weight % of polyethylene (Component I) having a weight average molecular weight of 2×105˜4×105 and less than 5 weight % of molecules of which molecular weight is less than 1×104 and less than 5 weight % of molecules of which molecular weight is greater than 1×106, and 2-10 weight % of polypropylene (Component II) of which weight average molecular weight is 3.0×104˜8.0×105 and the peak of the melting point is higher than 145° C., and 80-50 weight % of a diluent (Component III), to mold in the form of sheets; stretching the above sheets to the form of films; extracting the diluent from the above films; and heat-setting the above films.

Abstract: The present invention is related to microporous polyolefin films that may be used for battery separators and the methods of manufacturing the same. These microporous polyolefin films are characterized by being manufactured in a method comprising the steps of melt-extruding a composition, comprised of 20-50 weight % of a resin composition, comprised of 90-98 weight % of polyethylene (Component I) having a weight average molecular weight of 2×105-4×105 and less than 5 weight % of molecules of which molecular weight is less than 1×104 and less than 5 weight % of molecules of which molecular weight is greater than 1×106, and 2-10 weight % of polypropylene (Component II) of which weight average molecular weight is 3.0×104-8.0×105 and the peak of the melting point is higher than 145° C., and 80-50 weight % of a diluent (Component III), to mold in the form of sheets; stretching the above sheets to mold in the form of films; extracting the diluent from the above films; and heat-setting the above films.

Abstract: Microporous films of the semicrystalline polymer resin according to the present invention are obtained by stretching semicrystalline polymer resin sheets extruded through a die by the phase separation between a semicrystalline polymer resin and a diluent, of which cross-section is comprised of a pore region and a non-crystalline region which is in the main matrix phase and is a swelling region swelled by the diluent, and extracting the diluent. The pore region has irregular sizes and shapes, has an average diameter of 0.01 (m to 2 (m, is connected in three dimensions, penetrates the thickness of the sheet, has gas permeability, has a volume ratio with respect to the volume of the entire resin composition of 10% to 40%. The swelled non-crystalline region has a swelling ratio of 200% or greater and is a region making minute cells of which average diameter is 0.01 (m to 1 (m as the region is split and cells are formed during the process of stretching.

Abstract: Microporous films of the semicrystalline polymer according to the present invention are obtained by stretching semicrystalline polymer sheets extruded through a die with the phase separation between a semicrystalline polymer resin and a diluent, of which sheet is comprised of a crystalline region, a pore region, and a non-crystalline region which is a swollen region swollen by the diluent, and extracting the diluent. The pore region has irregular sizes and shapes, has an average diameter of 0.01 ?m to 2 ?m, is connected in three dimensions, penetrates the thickness of the sheet, has gas permeability, and has a volume ratio with respect to the volume of the entire composition of 10% to 40%. The swollen non-crystalline region has a swelling ratio of 200% or greater and is a region making micropores of which average diameter is 0.1 ?m to 1 ?m as the region is split and pores are generated during the process of stretching. Thus manufactured microporous films are characterized by having a gas permeability of 1.

Abstract: Disclosed in the present invention are a microporous polyethylene film and a method of manufacture thereof. The polyethylene microporous film manufactured according to the present invention may contribute to an increased productivity of stable products as its extrusion and stretching may be done readily. And thus manufactured product may be used for battery separators and various filters owing to its high gas permeability, superior puncture strength, and small ratio of shrinkage.

Abstract: The present invention discloses a microporous high-density polyethylene film for a battery separator, and process for preparing the same. The microporous high-density polyethylene film according to the present invention comprises of high-density polyethylene with weight average molecular weight of 2×105˜4×105, containing not more than 5 wt % of molecules with molecular weight of 1×104 or less and not more than 5 wt % of molecules with molecular weight of 1×106 or more, and has the properties of puncture strength of 0.22 N/?m or more, Darcy's permeability constant of 1.8×10?5 Darcy or more, and shrinkage of 4% or less in machine and transverse direction, respectively. Particularly, the microporous high-density polyethylene film has excellent extrusion-compoundability and stretchability with high productivity and enhances performances and stability of the battery using the film.

Abstract: Disclosed is a matte biaxially oriented polypropylene film having improved matte characteristic and processability. The film comprises one or more surface layers made of a composition comprising 100 parts by weight of a resin blend of 40-60 wt % of polyethylene (I) and 60-40 wt % of polypropylene (II), 0.005-0.04 parts by weight of a peroxide (III) and 0.1-0.5 parts by weight of a fluoroelastomer or a metal stearate (IV). The matte biaxially oriented film has low gloss (45°, <10%) and high haze (>70%), and solves problems related to increase of silver (or bright) spots and roughness of a matte pattern, and a shortened die cleaning cycle due to die build-up.

Abstract: Disclosed is a matte biaxially oriented polypropylene film having improved matte characteristic and processability. The film comprises one or more surface layers made of a composition comprising 100 parts by weight of a resin blend of 40-60 wt % of polyethylene (I) and 60-40 wt % of polypropylene (II), 0.005-0.04 parts by weight of a peroxide (III) and 0.1-0.5 parts by weight of a fluoroelastomer or a metal stearate (IV). The matte biaxially oriented film has low gloss (45°, <10%) and high haze (>70%), and solves problems related to increase of silver (or bright) spots and roughness of a matte pattern, and a shortened die cleaning cycle due to die build-up.