Granted Patent
Utility
US 4,933,083 · App. 06/723,128
Polybenzimidazole thin film composite membranes
Inventor:
R. Sidney Jones, Jr.
Patented Case
View Patent ↗
Granted: Jun 12, 1990
Filed: Apr 15, 1985
Inventor
R. Sidney Jones, Jr.
Assignee (at issue)
Hoechst Celanese Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.