公开(公告)号：JP2002119833A

公开(公告)日：2002-04-23

申请号：JP2000314696

申请日：2000-10-16

Applicant: NOK CORP

Inventor： URAKAWA TETSUYA

IPC: D06L1/12 ,  B01D61/20 ,  B01D65/06 ,  B01D69/08 ,  B01D71/68

Abstract: PROBLEM TO BE SOLVED: To provide a method for washing a hollow polysulfone fiber membrane manufactured by a dry wet spinning method and excellent in water permeability and eliminating the generation of malodorous taste at the permeation of city water membrane manufactured. SOLUTION: The porous polysulfone hollow fiber membrane prepared by the dry wet spinning method by adding high-molecular weight polyvinyl pyrrolidone having a molecular weight of not less than about 1,000,000 is washed with a hypochlorite aqueous solution.

公开(公告)号：JP2000093768A

公开(公告)日：2000-04-04

申请号：JP26597498

申请日：1998-09-21

Applicant: NOK CORP

Inventor： URAKAWA TETSUYA

IPC: B01D53/22 ,  B01D69/08

Abstract: PROBLEM TO BE SOLVED: To improve the mechanical strength of a composite membrane of a porous hollow fiber membrane and use the same as a microfiltration membrane or an ultrafiltration membrane. SOLUTION: This composite porous hollow fiber membrane is formed by laminating a dry and wet spun active porus membrane or a wet spun active porous membrane on a melt and draw spun porous hollow fiber membrane, and the composite membrane is formed by inserting a melt and draw spun porous hollow fiber membrane into a core of a double annular nozzle, and extruding together with a membrane forming stock solution of an active porous membrane forming resin out of the double annular nozzle by dry and wet spinning or wet spinning. As the melt and draw spun porous hollow fiber membrane, polyethylene, polypropylene, a polyolefin such as poly (4- methylponte-1), polytetrafluoroethylene, a thermoplastic polyminide or the like is spun into the porous hollow fiber membrane shape by the melt spinning method, and the membrane is so drawn as to form the approximately 0.1-5 mm outer diameter, preferably approximately 0.2-2 mm and also the approximately 0.08-3 mm inner diameter, preferably approximately 0.15-1.5 mm is used. The porous hollow fiber membrane thus formed is provided with the approximately 0.01-0.1 μm average pore diameter.

公开(公告)号：JPH1176778A

公开(公告)日：1999-03-23

申请号：JP25767297

申请日：1997-09-05

Applicant: NOK CORP

Inventor： SAITO MASAHARU ,  URAKAWA TETSUYA

IPC: B01D69/08 ,  B01D53/26 ,  B01D71/64

Abstract: PROBLEM TO BE SOLVED: To improve dehumidifying performance by preparing a dehumidifying membrane from a hollow fiber membrane produced from polyether imide. SOLUTION: This polyether imide dehumidifying membrane is suitable for dehumidification in compressed air and consists of a hollow fiber membrane produced from polyether imide. The dehumidifying device is produced by preparing a module of the hollow fiber membrane in such a manner that air containing water vapor supplied through the entrance of the module is dehumidified by the hollow fiber membrane and discharged through a primary air exit (module exit) as a dry air, while the water vapor removed is permeated through the hollow fiber membrane and discharged through a secondary side on the module cylinder. The hollow fiber membrane used is produced by dry and wet spinning of a spinning source liquid containing 18 to 30 wt.% polyether imide dissolved. The inner surface of the hollow fiber membrane is preferably coated with a polyvinylpyrrolidone. If necessary, the hollow fiber membrane is impregnated with a moisture holding agent.

公开(公告)号：JPH06233921A

公开(公告)日：1994-08-23

申请号：JP4574493

申请日：1993-02-10

Applicant: NOK CORP

Inventor： URAKAWA TETSUYA

IPC: B01D69/08 ,  B01D71/68 ,  D01F6/76

Abstract: PURPOSE:To produce a polysulfone porous hollow yarn membrane excellent in film forming properties and water permeability by emitting a film forming raw soln. and a core soln. from a double annular nozzle to subject them to dry and wet spinning. CONSTITUTION:A film forming raw soln. composed of an org. solvent soln. of polysulfone is emitted from a double annular nozzle along with a core soln. to subject both solns. to dry and wet spinning. In this method, a high viscosity film forming raw soln. with viscosity of 2000-4000 cps (24 deg.C) is used as the film forming raw soln. and the same org. solvent as the film forming raw soln. is used as the core soln.