IP Library › Granted Patent US 4,976,897
Granted Patent Utility
US 4,976,897 · App. 07/133,824

Composite porous membranes and methods of making the same

Inventors: Robert W. Callahan, Richard D. Johnson
Patented Case View Patent ↗
Granted: Dec 11, 1990 Filed: Dec 16, 1987
Inventors
Robert W. Callahan
Richard D. Johnson
Assignee (at issue)
Hoechst Celanese Corporation

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Quick Facts
Patent No.
US 4,976,897
App. No.
07/133,824
Filed
1987-12-16
Granted
1990-12-11
Kind
A