Granted Patent
Utility
US 4,931,070 · App. 07/350,849
Process and system for the production of dry, high purity nitrogen
Inventor:
Ravi Prasad
Patented Case
View Patent ↗
Granted: Jun 5, 1990
Filed: May 12, 1989
Inventor
Ravi Prasad
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.