Patent · US Expired

Process for producing microporous PTFE

US5677047A · kind A · utility

9Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 7, 1995
Grant dateOct 14, 1997
Priority date
Expiry dateJun 7, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/249978
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A substantially cylindrical bar of microporous PTFE is non-fibrillated and incorporates pores within any cylindrical surface within the bar centred about the central longitudinal axis of the bar that are of substantially uniform size and are substantially uniformly distributed within that surface. The process for producing such a bar includes the step of applying a substantially radial compressive force to pre-heated and cooled granules of PTFE and subsequently re-heating and cooling the compressed granules, while a film of non-fibrillated, microporous PTFE is formed from the cooled bar, the plane of the film being perpendicular to the direction of the radial compressive force whereby the pores within any plane substantially perpendicular to the thickness of the film are of substantially uniform size and are substantially uniformly distributed within that plane and all such parallel planes.

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