Granted Patent
Utility
US 5,273,821 · App. 07/790,938
High strength ceramic fiber board
Inventors:
James R. Olson, Mark D. Stahlman
Patented Case
View Patent ↗
Granted: Dec 28, 1993
Filed: Nov 12, 1991
Inventors
James R. Olson
Mark D. Stahlman
Assignee (at issue)
Carborundum 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.