MICROPOROUS POLYOLEFIN FILM AND ITS PRODUCTION

摘要

PURPOSE:To provide a microporous polyolefin film having excellent separation accuracy and improved gas or liquid permeability and provide a process for producing the film. CONSTITUTION:A microporous polyolefin film is produced from a solution of a polyolefin containing an ultra-high molecular weight component and having broad molecular weight distribution. In the above process, bubbles having a size not to extend between both faces are used as the dispersed phase to decrease the substantial film thickness.