Patent · US Expired

Composite hydrophilic membrane and method for manufacture thereof

US4670146A · kind A · utility

31Cited by
5References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 23, 1982
Grant dateJun 2, 1987
Priority date
Expiry dateJun 23, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E50/10
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

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.

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