| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly heat-resistant, cross-linked microporous polyethylene film which does not undergo the degradation with time due to remaining free radicals and is excellent in mechanical strengths, permeability, and productivity. SOLUTION: By subjecting a gel-like stretched film before extraction to a cross-linking treatment and a heat treatment, remaining free radicals are deactivated without decreasing the mechanical strengths and permeability of the objective microporous film, thus preventing the degradation in strength with time. COPYRIGHT: (C)2004,JPO |
