Patent ID: 8901240

Claim:
A polypropylene resin composition for use in the formation of a microporous membrane comprising as an essential component a propylene homopolymer (A) that satisfies the following requirements (1) to (4) and (7): (1) the intrinsic viscosity [η] measured with a decalin solution is 1 dl/g or more and less than 7 dl/g; (2) the mesopentad fraction as measured by 13 C-NMR (nuclear magnetic resonance) ranges from 94.0% to 99.5%; (3) the integral elution volume during heating to 100° C. as measured by cross fractionation chromatography (CFC) using o-dichlorobenzene is 10% or less; (4) the melting point as measured with a differential scanning calorimeter (DSC) ranges from 153° C. to 167° C.; and (7) in an elution temperature-elution volume curve measured by cross fractionation chromatography (CFC) using o-dichlorobenzene, the maximum peak has a peak top temperature in the range of 105° C. to 130° C. and a half-width of 7.0° C. or less.