| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a microporous film of a crystalline polymer with uniform mean pore-diameter distribution in a plane, capable of catching particles without allowing them to leak even upon using the same of a large area, free of clogging, having a high flow capacity, and having a long filtration life, a method of efficiently producing a microporous film of a crystalline polymer, and a filter for use in filtration that employs the microporous film of a crystalline polymer. <P>SOLUTION: The method of producing a microporous film of a crystalline polymer includes an asymmetrical heating process of heating one surface of an immobilized film made of a crystalline polymer using a heating means at a temperature not lower than the melting point of the calcined crystalline polymer while maintaining the film in a state of contacting the heating means to produce a half-calcined film wherein a temperature gradient is formed in the direction of the thickness of the film, and a stretching process of stretching the half calcined film. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
