Hollow fiber membrane, and method for producing hollow fiber membrane
AssigneeKuraray Co., Ltd.
InventorsYouhei Yabuno, Tsukasa Yoshitoshi, Yusuke Hayashi
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Abstract
One aspect of the present invention concerns a porous hollow fiber membrane containing a vinylidene fluoride-based resin. The hollow fiber membrane has a gradient structure in which a pore diameter of pores in the hollow fiber membrane gradually becomes smaller at least toward one of inner and outer peripheral surface sides and is hydrophilized by containing a crosslinked body of a polyvinylpyrrolidone-based resin.
Claims7
A porous hollow fiber membrane, comprising a vinylidene fluoride-based resin, wherein the hollow fiber membrane has a gradient structure in which a pore diameter of pores in the hollow fiber membrane gradually becomes smaller at least toward one of inner and outer peripheral surface sides;
- the hollow fiber membrane is hydrophilized by containing from 0.1 to 15 mass % of a crosslinked body of a polyvinylpyrrolidone-based resin;
- and
- a ratio (FD10/FW) of a water permeation speed (FD10) at an inter-membrane differential pressure of 0.1 MPa in the dry state after wet and dry states are alternately repeated ten times to a water permeation speed (FW) at an inter-membrane differential pressure of 0.1 MPa in the wet state is 40% or higher;
- wherein a K-value of the polyvinylpyrrolidone-based resin is from 60 to 120.
Dependencies are inferred from the claim text.