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:
Jun. 02, 1987
Filed:
Jun. 23, 1982
Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A composite hydrophilic membrane comprising a very thin semipermeable hydrophilic membrane containing a sulfonic group and a polyethylenic microporous membrane containing sulfonic group. This hydrophilic membrane has specially high permeation rate of water and excellent separation ability. The composite hydrophilic membrane is manufactured by a method which comprises fusing a very thin membrane containing an ethylenic copolymer onto the surface of a polyethylenic microporous membrane or a polyethylenic membrane capable of being converted into a microporous membrane thereby forming a composite film, converting the resin film prior to and/or during and/or after sulfonation into a microporous membrane, and causing the composite film to react with a sulfonating agent. This method permits easy and efficient production of the composite hydrophilic membrane.