Abstract: Disclosed herein is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film is made from a resin composition. The resin composition comprises 100 parts by weight of a polyethylene composition including 10-50 wt % polyethylene having a weight average molecular weight of from 2×105 to less than 5×105 (component I) and 90-50 wt % diluent (component II), and 0-150 parts by weight of inorganic powder (component III). The film has a puncture strength of 0.20 N/?m or more and a gas permeability (Darcy's permeability constant) of 1×10?5 Darcy or more. The microporous polyethylene film has excellent physical properties, thus improving the performance and stability of a battery.

Abstract: Disclosed herein is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film is made from a resin composition. The resin composition comprises 100 parts by weight of a polyethylene composition including 10-50 wt % polyethylene having a weight average molecular weight of from 2×105 to less than 5×105 (component I) and 90-50 wt % diluent (component II), and 0-150 parts by weight of inorganic powder (component III). The film has a puncture strength of 0.20 N/?m or more and a gas permeability (Darcy's permeability constant) of 1×10?5 Darcy or more. The microporous polyethylene film has excellent physical properties, thus improving the performance and stability of a battery.

Abstract: Disclosed is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film comprises a resin mixture, which includes 100 parts by weight of composition containing 20-50 wt % polyethylene with a weight average molecular weight of 5×104-3×105 (component I) and 80-50 wt % diluent (component II), 0.1-2 parts by weight of peroxide (component III), and 0.05-0.5 parts by weight of anti-oxidant (component IV). The microporous polyethylene film has a puncture strength of 0.22 N/?m or more and a gas permeability (Darcy's permeability constant) of 1.3 Darcy or more. The present invention increases production efficiency of the microporous film, and improves performances and stability of the battery when the microporous polyethylene film is used in a battery separator.

Abstract: Disclosed is a microporous polyethylene film for a battery separator and a method of producing the same. The microporous polyethylene film comprises a resin mixture, which includes 100 parts by weight of composition containing 20-50 wt % polyethylene with a weight average molecular weight of 5×104-3×105 (component I) and 80-50 wt % diluent (component II), 0.1-2 parts by weight of peroxide (component H), and 0.05-0.5 parts by weight of anti-oxidant (component IV). The microporous polyethylene film has a puncture strength of 0.22 N/?m or more and a gas permeability (Darcy's permeability constant) of 1.3×10?5 Darcy or more. The present invention increases production efficiency of the microporous film, and improves performances and stability of the battery when the microporous polyethylene film is used in a battery separator.

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.