Polypropylene resin composition for microporous film and use of polypropylene resin composition

A microporous film, comprising:

• at least one porous layer of a mixture of (A) and (B):
• (A) 5 to 30% by weight based on the total weight of the mixture of a polypropylene resin (X) having a long chain branched structure and the following properties (i) to (vi):
• (i):
• an MFR of 0.1 to 30.0 g/10 min;
• (ii):
• a molecular weight distribution wherein Mw/Mn is 3.0 to 10.0 and Mz/Mw is 2.5 to 10.0 by GPC;
• (iii):
• a melt tension MT in grams satisfying the following formula:
• log(MT)≥−0.9×log(MFR)+0.7 or MT≥15;
• (iv):
• a branching index g′ of 0.30 or more and less than 0.95;
• (v):
• a mm fraction of propylene unit triads of 95% or more by 13C-NMR;
• and
• (vi):
• when formed into an unstretched film having a thickness of 25 μm, a number of gels having a major axis of 0.5 mm or more of 10 gels/m2 or less, and
• (B) 70 to 95% by weight based on total weight of the mixture of a polypropylene resin (Y) having an MFR of 0.1 to 10 g/10 min and excluding the polypropylene resin (X);
• wherein the porous layer has a plurality of micropores of 2 μm or less and a thickness of 40 μm or less.