| abstract |
(1) a combination of a microporous layer made of a polyethylene resin and a microporous layer made of polypropylene and a heat-resistant resin having a melting point or a glass transition temperature of 170° C. or higher, or (2) a combination of a microporous layer made of a polyethylene resin and a microporous layer made of polypropylene and inorganic filler having an aspect ratio of 2 or more provides a multi-layer, microporous polyolefin membrane with well-balanced permeability, mechanical strength, heat shrinkage resistance, shutdown properties and meltdown properties. |