| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a polyolefin microporous film which can show both low air permeability and high withstand voltage performance. SOLUTION: The method of manufacturing a polyolefin microporous film includes the following processes (A) and (B): (A) a sheet forming process in which a raw material composition containing a polyolefin resin, a filler, and a plasticizer are kneaded to form a sheet, and (B) a stretching process after the process (A) in which the plasticizer is extracted from the sheet to form a filler containing microporous sheet, and two or more of the filler-containing microporous sheets are piled and stretched in TD. COPYRIGHT: (C)2010,JPO&INPIT |
