Granted Patent
Utility
US 4,934,148 · App. 07/350,848
Dry, high purity nitrogen production process and system
Inventors:
Ravi Prasad, Oscar W. Haas, Harry Cheung
Patented Case
View Patent ↗
Granted: Jun 19, 1990
Filed: May 12, 1989
Inventors
Ravi Prasad
Oscar W. Haas
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.