| abstract |
In a polyolefin microporous membrane having a porosity of 45% to 85%, the maximum pore diameter is 0.1 μm to 0.23 μm, the MD elastic modulus is 400 to 2000 MPa, and the MD elastic modulus / TD elastic modulus ratio is 1.5 to 9 By setting, a polyolefin microporous membrane that easily absorbs strain when subjected to compression and has excellent permeability and excellent insulation performance even after compression is provided. |