Breathable film and process for production of the same.

摘要

A linear polyethylene (100 wt parts) of low density of 0.870 to 0.915 g/cc and containing 15 to 50 wt% of components extractable with xylene at 25+/-1 DEG C and a weight average molecular chain length of 1,000 - 9,000 ANGSTROM ngstroms is mixed with 50-400 parts of an organic or inorganic filler (e.g. calcium carbonate, barium sulfate or talc) and optionally to help dispersion of the filler 0.5-8 parts of a nonionic surfactant (e.g. a glycerine or sorbitan ester of a C12-22 fatty acid) and the mixture is molded into a film. The film is stretched either (a) uniaxially at 30-80 DEG C at a stretch ratio of 1.2-8 in the mechanical direction or (b) biaxially at 40-100 DEG C at a ratio of 1.1-8.0 in the mechanical direction and then at 70-100 DEG C at a ratio of not above 6.0 transversely; optionally a heating setting treatment is then applied. The resultant film formed from the stretched composition is breathable to a high extent and has good strength, touch and appearance.