Biaxially stretched polypropylene film

Abstract

Provided is a polypropylene film that enables stable film formation for a longer period of time, and that has higher voltage endurance (in particular, voltage endurance at high temperatures) and a higher yield rate. The biaxially stretched polypropylene film has a first surface and a second surface, the average maximum length of substantially elliptical spots on the first surface being 3.0 mm or less, and the difference between the average reduced peak height Rpk outside the spots and the average reduced peak height Rpk within the spots being 0.040 μm or less.

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