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:
Aug. 25, 1981
Filed:
May. 01, 1979
Applicant:
Inventors:
Assignee:
Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; B32B / ; B01D / ;
U.S. Cl.
CPC ...
428305 ; 2105 / ; 260 / ; 264 41 ; 2641 / ; 2641 / ; 264204 ; 264209 ; 428332 ; 428335 ; 428336 ; 428398 ; 428419 ;
Abstract
A semipermeable membrane made of a polyaryl ether sulfone comprised of recurring units represented by the general formula (I): ##STR1## wherein X, X', X' and X'' are non-dissociative substituents, and l, m, n and o are integers of from 0 to 4. The membrane, which is composed of a single continuous polymer phase, has pores of a diameter increasing progressively and continuously from the surface layers to the center portion thereof. The membrane is prepared by the process wherein: