Granted Patent
Utility
US 5,340,558 · App. 08/076,663
Vermiculite composition with improved thermal expansion properties
Inventors:
Semyon D. Friedman, Robert W. McKinney, Chia-Chih Ou, Robert M. Spotnitz, Shaohai Wu
Patented Case
View Patent ↗
Granted: Aug 23, 1994
Filed: Jun 14, 1993
Inventors
Semyon D. Friedman
Robert W. McKinney
Chia-Chih Ou
Robert M. Spotnitz
Shaohai Wu
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.