PRODUCTION OF AIR-PERMEABLE FILM

摘要

PROBLEM TO BE SOLVED: To produce an air-permeable film having a uniform thickness, good air permeability and good high-speed orientability. SOLUTION: This air-permeable film is produced by uniaxially orienting a film made from a composition comprising 30-50 pts.wt. polyolefin resin and 70-50 pts.wt. inorganic filler. The polyolefin resin used is a mixture comprising 80-98 wt.% linear low-density polyethylene having a melt index of 0.8-5.0 g/10 min and a density of 0.910-0.940 g/cm<3> and 20-2 wt.% linear low-density polyethylene having a melt index of 0.01-0.5 g/10 min and/or high-density polyethylene.