Granted Patent
Utility
US 4,420,469 · App. 06/384,077
Pyrohydrolysis of columbium oxyfluoride to columbium oxide
Inventors:
Roger M. Bergman, Edwin J. Bielecki, Charles R. Nippert, Jr.
Patented Case
View Patent ↗
Granted: Dec 13, 1983
Filed: Jun 1, 1982
Inventors
Roger M. Bergman
Edwin J. Bielecki
Charles R. Nippert, Jr.
Assignee (at issue)
Cabot 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.