Granted Patent
Utility
US 4,804,397 · App. 07/133,963
Partial press in gravity bending furnace and method of use
Inventors:
Joseph D. Stas, Robert G. Frank, James H. Schwartz
Patented Case
View Patent ↗
Granted: Feb 14, 1989
Filed: Dec 16, 1987
Inventors
Joseph D. Stas
Robert G. Frank
James H. Schwartz
Assignee (at issue)
PPG Industries, Inc.
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.