| 摘要 |
<p>This invention is related to a porous hollow filament membrane mainly composed of a polytetrafluoroethylene resin and a process for producing a porous membrane, which comprises forming a mixture of a polytetrafluoroethylene resin dispersion with a filament-forming polymer into hollow or sheet-like form, heat-treating the resulting membrane at a temperature above the melting point of the resin, and removing the filament-forming polymer. This process enables porous polytetrafluoroethylene resin membranes with various pore sizes and void ratios to be produced by changing the kind or amount of additives to the starting mixture, and provides a new technique of separating substances in a high-temperature and strongly decomposing or strongly dissolving medium.</p> |
