Granted Patent
Utility
US 3,963,805 · App. 05/519,268
Water swellable poly(alkylene oxide)
Inventor:
Nan S. Chu
Patented Case
View Patent ↗
Granted: Jun 15, 1976
Filed: Oct 30, 1974
Inventor
Nan S. Chu
Assignee (at issue)
Union Carbide 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.