| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for stably and efficiently producing a microporous membrane excellent in property balance among void content, gas permeability, mechanical strength, a heat-resistant shrink characteristic, and a shutdown property, and uses of microporous membranes obtained by that producing method. SOLUTION: This method comprises the steps of performing biaxial stretching and removing a solvent, after forming a gel-like molding by melting and kneading a thermoplastic resin and a solvent, pushing the obtained melted kneaded object out from a die, and cooling it. In the method, each of the longitudinal and transverse stretching speed values of the biaxial stretching is made 85%/s or more. COPYRIGHT: (C)2005,JPO&NCIPI |
