Process for producing porous articles of polytetrafluoroethylene
Abstract
Abstract A POROUS ARTICLE OF POLYETRAFLUOROETHYLENE HAVING FINE OPEN CELLS AND HAVING HIGH STRENGTH AND PLIABILITY IS PRODUCED BY STRECTHING A SHEET OF POLYTETRAFLUOROETHYLENE AT LEAST BIAXIALLY. A POROUS FILM OF POLYTETRAFLUOROETHYLENE HAVING ESPECIALLY LARGE GAS-PERMEABLITY IS OBTAINED BY PERFORMING THE ABOVE STRETCHING IN A LIQUID, SUCH AS CARBON TETRACHLORIDE OR METHANOL WHICH IS A NON-SOLVENT FOR POLYTETRAFLUOROETHYLENE AND IS CAPABLE OF WETTING POLYTETRAFLUOROETHYLENE OR PENETRATING INTO THE FINE PORES FORMED IN THE SHEET DURING STRETCHING. THE PRODUCT FINDS A WIDE RANGE OF APPLICATIONS INCLUDING FILTERS FOR STRONGLY CORROSIVE GASES OR DIAPHRAGMS FOR SEPARATING INSOTOPES OR URANIUM CONCENTRATION.
Inventors
- 👤 N Murayama
- 👤 T Katto
- 👤 S Funabashi
Bibliographic Details
Claims Analysis
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