The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 30, 1999
Filed:
Feb. 03, 1993
Robert D Mahoney, Danville, CA (US);
Jiro Kawamoto, Walnut Creek, CA (US);
Richard A Lundgard, Antioch, CA (US);
Mark F Sonnenschein, Antioch, CA (US);
Hawk S Wan, Antioch, CA (US);
H Nelson Beck, Walnut Creek, CA (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
The invention relates to a process for preparing a microporous membrane from an unsulfonated poly(phenylene sulfide) polymer by forming a mixture of an unsulfonated poly(phenylene sulfide) polymer, an amorphous polymer, and optionally a plasticizer, heating the resulting mixture, extruding or optionally casting the mixture into a membrane, controlled cooling (quenching) or coagulating the membrane, and leaching the membrane, while optionally drawing the membrane before, during, and/or after leaching.