Title:
SKIN-FORMED HOLLOW FIBER MEMBRANE AND PRODUCTION METHOD THEREOF
Document Type and Number:
Japanese Patent JP2015061727
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide an asymmetric hollow fiber porous membrane in which at least one surface composed of tetrafluoroethylene-perfluoro(alkylvinyl ether) copolymer (Poly(PTFE-CO-PFVAE) or tetrafluoroethylene-hexafluoropropylene copolymer (FEP) is formed into skin.SOLUTION: A method of producing a skin-formed hollow fiber membrane comprises dissolving a perfluoro-formed thermoplastic polymer in a chlorotrifluoroethylene oligomer solvent forming an upper critical consolute-temperature solution with the polymer, supplying the resultant solution to an internal cavity of an extrusion molding from the central part of an annular die while extruding from the die, extruding into a liquid in a cooling bath through an air gap to form a gel-like fiber, cooling the solution to a temperature equal to or lower than the upper critical consolute temperature to separate the solution into a solid phase rich in polymer and a liquid phase rich in the solvent, forming an asymmetric microporous hollow fiber membrane having a skin-formed outer surface by extracting the solvent from the gel-like fiber and drying the asymmetric microporous hollow fiber membrane.
Inventors:
CHENG KWOK-SHUN
GATES T DEAN
YEN LARRY Y
PATEL RANJIKANT B
GATES T DEAN
YEN LARRY Y
PATEL RANJIKANT B
Application Number:
JP2014207363A
Publication Date:
April 02, 2015
Filing Date:
October 08, 2014
Export Citation:
Assignee:
ENTEGRIS INC
International Classes:
B01D71/32; B01D61/18; B01D63/02; B01D67/00; B01D69/00; B01D69/08; B01D69/12; B01D71/36; B01D71/38; D01D5/24; D01F6/12; D01F6/32
Domestic Patent References:
| JPH02208329A | 1990-08-17 | |||
| JPS6190707A | 1986-05-08 | |||
| JPH06170182A | 1994-06-21 | |||
| JPS6447407A | 1989-02-21 | |||
| JPS59229320A | 1984-12-22 | |||
| JPH09276400A | 1997-10-28 |
Attorney, Agent or Firm:
Katsuma Osaki