OLEFIN RESIN MICROPOROUS BIAXIALLY ORIENTED FILM, METHOD FOR PRODUCING THE SAME, HEAT-RESISTANT OLEFIN RESIN MICROPOROUS BIAXIALLY ORIENTED FILM, AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an olefin resin microporous biaxially oriented film.SOLUTION: The olefin resin microporous biaxially oriented film of the present invention has micropore portions and contains an olefin resin. The olefin resin contains 30-70 mass% of a component having a molecular weight of 50,000 or less and 5-30 mass% of a component having a molecular weight of 500,000 or more and has a weight-average molecular weight of 100,000-500,000. The olefin resin microporous biaxially oriented film has a piercing strength of 0.7 N or more and an air permeability of 75-400 s/100 mL.SELECTED DRAWING: None