Tubular film extrusion method of polypropylene.

摘要

Described is a film forming method for a polypropylene resin composition, which comprises subjecting a polypropylene resin composition composed of 5 to 95 parts by weight of a syndiotactic polypropylene and 95 to 5 parts by weight of an isotactic polypropylene to air-cooled tubular film extrusion. By the air-cooled method which has heretofore had difficulty in obtaining a highly-transparent film from conventional isotactic polypropylene, a film having excellent transparency can be obtained.