| 摘要 |
<p>A porous membrane of vinylidene fluoride resin that is suitable for use in water purification treatment, potable water production, industrial water production, wastewater treatment and other water treatments, excelling in fractionation performance, permeation performance and physical strength, and that can be easily produced at low cost. The porous membrane at its one surface has circular or elliptical micropores of 1:1 to less than 5:1 average major diameter to minor diameter ratio, and on its other surface has strip-shaped micropores of 5:1 or greater average major diameter to minor diameter ratio. The fractional particle diameter thereof is 0.2 mum or greater.</p> |
