Granted Patent
Utility
US 6,312,642 · App. 09/347,160
Method for controlling the oxygen content in valve metal materials
Inventor:
James A. Fife
Patented Case
View Patent ↗
Granted: Nov 6, 2001
Filed: Jul 2, 1999
Inventor
James A. Fife
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.