Granted Patent
Utility
US 5,257,206 · App. 07/663,595
Statistical process control for air separation process
Inventor:
Thomas C. Hanson
Patented Case
View Patent ↗
Granted: Oct 26, 1993
Filed: Apr 8, 1991
Inventor
Thomas C. Hanson
Assignee (at issue)
Praxair Technology, Inc.
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.