Patent ID: 8920913
Filing Date: 2014-12-30
Classification: B32B,H01M,Y02E,Y10T

Abstract:
1. A porous multi-layer film, comprising: a first layer having a porosity of 30 to 60% and an average pore diameter of 0.01 to 0.1 μm and a second layer adjacent to the first layer, the second layer having a porosity of 50 to 80% and having pores with a pore average plane diameter of 0.1 to 50 μm of 70% or more on the basis of the area of the entire pores of the second layer, wherein the second layer has a thickness of 3 μm or more and occupies 30 to 70% of the entire thickness of the porous multi-layer film, and is prepared to contain a general heat-resistant resin of 50 volume % or more of a resin composition and contain inorganic materials of 30 to 60 wt % together, and the general heat-resistant resin has a melting temperature of 160 to 180° C.; and the porous multi-layer film has a thickness of 9 to 50 μm, a loop stiffness to the machine direction of 0.008 mg/μm or more, a puncture strength of 0.15 N/μm or more, a permeability of 1.5×10