Granted Patent
Utility
US 4,650,498 · App. 06/681,734
Abrasion resistant silicon nitride based articles
Inventor:
Sergej-Tomislav Buljan
Patented Case
View Patent ↗
Granted: Mar 17, 1987
Filed: Dec 14, 1984
Inventor
Sergej-Tomislav Buljan
Assignee (at issue)
GTE Laboratories Incorporated
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.