Granted Patent
Utility
US 4,345,925 · App. 06/210,733
Process for the production of high pressure oxygen gas
Inventor:
Harry Cheung
Patented Case
View Patent ↗
Granted: Aug 24, 1982
Filed: Nov 26, 1980
Inventor
Harry Cheung
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.