| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a novel porous membrane 2 capable of improving the quality and mechanical strength of a reinforcing porous membrane for an electrolyte membrane. <P>SOLUTION: When the porous membrane 2 is formed by stretching a resin thin film 1, stretch is conducted in two stages of a first stretch process which is a pore formation rate-determining step and stretching in a higher speed stretching condition and of a second stretch process which is a resin orientation rate-determining step and stretching in a lower speed stretching condition than that in the pore formation rate-determining step. <P>COPYRIGHT: (C)2008,JPO&INPIT |
