| abstract |
To provide a separator for a non-aqueous secondary battery having excellent physical properties and performance such as heat resistance, shutdown function, thermal shrinkage rate, durability, etc. and excellent moldability. A separator for a non-aqueous secondary battery comprising a polyolefin microporous membrane and a heat resistant porous layer formed of a heat resistant resin and laminated on one or both sides of the microporous membrane, The heat-resistant porous layer contains an inorganic filler, and the inorganic filler has a particle size distribution in each of a particle diameter range of 0.01 to 0.05 μm and a range of 0.1 to 1.0 μm. And the inorganic filler is contained in the heat-resistant porous layer in a weight fraction of 40 to 95% by weight. Separator. [Selection figure] None |