Granted Patent
Utility
US 4,952,536 · App. 07/314,001
High strength Al.sub.2 O.sub.3
Inventor:
Jacob Block
Patented Case
View Patent ↗
Granted: Aug 28, 1990
Filed: Feb 23, 1989
Inventor
Jacob Block
Assignee (at issue)
W.R. Grace & Co. Conn.
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.