Granted Patent
Utility
US 4,994,095 · App. 07/443,208
Semipermeable membranes based on specific 4,4'-(1H-alkylidene)bis[2,3,6-trialkylphenol]type polyesters
Inventors:
James H. Kawakami, Natarajan Muruganandam, George L. Brode
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: Dec 6, 1989
Inventors
James H. Kawakami
Natarajan Muruganandam
George L. Brode
Assignee (at issue)
Union Carbide Industrial Gases Technology 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.