Granted Patent
Utility
US 4,211,086 · App. 06/019,450
Cryogenic breathing system
Inventors:
Rex D. Leonard, Jan Hulstyn
Patented Case
View Patent ↗
Granted: Jul 8, 1980
Filed: Mar 12, 1979
Inventors
Rex D. Leonard
Jan Hulstyn
Assignee (at issue)
Beatrice Foods Co.
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.