MICROPOROUS FILM, METHOD FOR PRODUCING THE SAME, AND SEPARATOR FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a microporous film excellent in high-temperature cycling property, productivity, and easiness in cell formation, especially when being used as a separator, and to provide a method for producing the same.SOLUTION: In a microporous film contains a resin composition containing a mixture of polypropylene and polyethylene as a main component, the content of the polypropylene in the mixture is 50 mass% or more, and the dynamic friction coefficient of the surface is 0.55 or less.