Patent · US Expired

Four layer cation exchange fluoropolymer membrane

US4983264A · kind A · utility

10Cited by
5References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 1988
Grant dateJan 8, 1991
Priority date
Expiry dateMar 28, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2327/18
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A cation exchange fluoropolymer membrane comprising at least three integrally laminated layers including a main layer made of a perfluorocarbon polymer having carboxylic acid groups as its ion exchange groups with an ion exchange capacity of from 1.4 to 2.0 meq/g dry resin and having a thickness of from 50 to 250 .mu.m, a sulfonic acid film surface layer formed on one side of said main layer, made of a perfluorocarbon polymer having sulfonic acid groups as its ion exchange groups with an ion exchange capacity of from 0.5 to 1.5 meq/g dry resin and having a thickness of from 5 to 50 m, and a carboxylic acid film surface layer formed on the other side of said main layer, made of a perfluorcarbon polymer having carboxylic acid groups as its ion exchange groups with an ion exchange capacity of from 0.5 to 1.3 meq/g dry resin and having a thickness of from 5 to 50 .mu.m, said sulfonic acid film surface layer and carboxylic acid film surface layer constituting the outer-most layers, respectively.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.