The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 06, 1984
Filed:
Jan. 28, 1983
Takashi Nohmi, Fuji, JP;
Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
An aromatic polysulfone type resin hollow fiber membrane having a thickness of less than 100 .mu.m and a three-layer structure of inner and outer surface skin layers and a void layer disposed therebetween and connected thereto. The hollow fiber membrane of the kind has an improved burst strength, while exhibiting an extremely excellent water permeability. Such a hollow fiber membrane can be produced by a process which comprises extruding a spinning solution of an aromatic polysulfone type resin in an organic polar solvent for said resin, said solution containing a glycol and having a resin concentration of from 10 to 35% by weight, from an annular spinning nozzle of which the orifice width is 10 to 110 .mu.m while simultaneously injecting an internal coagulating liquid into the annular spinning nozzle at an inside bore thereof, thereby to obtain an extrudate in the form of a hollow fiber, and introducing said extrudate into an external coagulating liquid.