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:
May. 12, 1992
Filed:
May. 29, 1990
Yoshio Himeshima, Otsu, JP;
Hideaki Tanisugi, Otsu, JP;
Tetsuo Watanabe, Otsu, JP;
Tadahiro Uemura, Kyoto, JP;
Masaru Kurihara, Otsu, JP;
Toray Industries, Inc., , JP;
Abstract
The present invention relates to a porous membrane which has excellent durability and is useful for ultrafiltration. The porous membrane of the present invention has heterogeneous structure, which consists essentially of a phenylenesulfide-based copolymer of the formula: (Ph--S--Ph--X--).sub.q -- (wherein Ph represents phenylene group, X represents --SO.sub.2 -- or --CO--, and g represents an integer from 80-400 which membrane has a dense layer on one or both surfaces of the membrane, the dense layer controlling the separation performance of the membrane, and a porous layer next to the dense layer, which porous layer has a porosity higher than that of the dense layer.