| abstract |
Polyolefin multilayer microporous membrane having a polyethylene resin layer and a polypropylene-containing layer and excellent in balance of permeability, mechanical strength, heat shrinkage resistance, shutdown characteristics and meltdown characteristics, a method for producing the same, and a battery Provide a separator. (1) A / B / A configuration comprising a porous layer A made of a polyethylene-based resin and a porous layer B containing polypropylene and a heat-resistant resin having a melting point or glass transition temperature of 170 ° C. or higher, Or (2) A polyolefin multilayer having an A ′ / B ′ / A ′ configuration comprising a porous layer A ′ made of a polyethylene-based resin and a porous layer B ′ containing an inorganic filler having an aspect ratio of 2 or more with polypropylene Microporous membrane. [Selection figure] None |