Process of producing porous polypropylene hollow fiber and film

摘要

A process of producing a porous polypropylene hollow fiber or film which comprises a step for forming a large number of micropores in the surrounding wall of said fiber or in said film by drawing a polypropylene hollow fiber or film, which is characterized in that the drawing process is performed at a temperature in the range of 110 DEG -155 DEG C. and at a drawing rate of less than 10%/min.