Granted Patent
Utility
US 4,919,690 · App. 07/133,231
Method for purifying a continuous flow of helium and/or neon gas
Inventor:
James E. Lovelock
Patented Case
View Patent ↗
Granted: Apr 24, 1990
Filed: Dec 17, 1987
Inventor
James E. Lovelock
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.