Patent · US Active

Method of producing a microporous polyolefin membrane

US8075818B2 · kind B2 · utility

0Cited by
12References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 27, 2004
Grant dateDec 13, 2011
Priority date
Expiry dateJan 23, 2029

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/249991
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method for producing a microporous polyolefin membrane formed by fine fibrils, the membrane comprising (A) a polyolefin having a weight-average molecular weight of 5×105 or more or (B) a composition containing Component (A), connected to each other, and having micropores of 0.05 to 5 μm in average pore size and crystal lamellas of Component (A) or (B) being in a specific alignment state. The method includes extruding a solution of Component (A) or (B) in a solvent into a gel-like formed article; thermally setting the article, with or without stretching, at least at the crystal dispersion temperature of Component (A) or (B), but at melting point of Component (A) or (B) plus 30° C. or lower; and removing the solvent.

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