| abstract |
A polyolefin microporous membrane comprising polyethylene and polypropylene as essential components and comprising a laminated film of two or more layers, wherein the mixing ratio of polypropylene in at least one surface layer is more than 50% by weight and 95% by weight or less, and A polyolefin microporous membrane having a polyethylene content of 50 wt% or more and 95 wt% or less in the entire membrane. |