Patent · US Expired

Method for preparing a porous structure by stretching a resin sheet useful as an electrode separator

US4024213A · kind A · utility

8Cited by
9References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 19, 1975
Grant dateMay 17, 1977
Priority date
Expiry dateFeb 19, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/47
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A resin sheet having a porous layered structure useful as an electrode separator for electric cells, said sheet comprising (a) an olefin resin, (b) a finely divided inorganic substance, and (c) at least one substance selected from the group consisting of (i) a water-swellable thermoplastic resin, (ii) a water-insoluble or difficultly water-soluble hydrophilic nonionic surface active agent, and (iii) a water-insoluble difficultly water-soluble hydrophilic anionic surface active agent, said sheet including fine pores arranged throughout its cross section in a plurality of layers, at least some of them forming open cells. The above sheet is prepared by a process comprising fabricating a mixture containing the above components (a), (b) and (c) into a sheet, and stretching the sheet in at least one direction.

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