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:
Sep. 22, 1992
Filed:
Dec. 07, 1990
Tetsuji Shimohira, Yokohama, JP;
Yoshiaki Higuchi, Yokohama, JP;
Yoshihiko Saito, Yokohama, JP;
Kohji Suzuki, Yokohama, JP;
Asahi Glass Company Ltd., Tokyo, JP;
Abstract
A fluorine-containing cation exchange membrane for electrolysis, which comprises a multi-layered structure prepared by integrally laminating (i) the first ion exchange layer having --COOM groups (M is hydrogen or an alkali metal) in an ion exchange capacity of from 0.6 to 2.0 meq/g dry resin and having a thickness of from 5 to 300 .mu.m, (ii) the second ion exchange layer present on the anode side of the first ion exchange layer, the second ion exchange layer having a smaller specific resistance and a larger thickness than the first ion exchange layer, and (iii) a hydrophilic asymmetric porous layer present on the cathode side of the first ion exchange layer, the porous layer having a water-permeability which becomes smaller in proportion as closer to the cathode side, and a process for producing an alkali metal hydroxide by using the above fluorine-containing cation exchange membrane.