| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vinylidene fluoride type resin hollow filament porous membrane which has a pore size smaller than before and relatively large permeability, and has excellent antifouling property coupled with contamination removal efficiency by backwash and/or bubbling. Ž<P>SOLUTION: The vinylidene fluoride type resin hollow filament porous membrane is a non-stretch porous membrane in a hollow filament shape composed of a vinylidene fluoride type resin of which weight average molecular weight Mw is 500,000 or more and the ratio Mw/Mn of the weight average molecular weight Mw and number average molecular weight Mn is 2.0 or more. The ratio F(L=200 mm, v=70%)/Pm<SP>4</SP>of a corresponding value F(L=200 mm, v=70%)(m/day) to porosity v=70% of the permeability in a test length L=200 mm measured under the condition of a differential pressure of 100 kPa and a water temperature of 25°C and a fourth power value Pm<SP>4</SP>of an average bore size Pm(μm) based on a pore size distribution by a half dry/bubble point method (ASTM-F316 and ASTM-E1294) is ≥5×10<SP>5</SP>(m/day*μm<SP>4</SP>). Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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