Granted Patent
Utility
US 4,994,545 · App. 07/413,960
Polyetherimide
Inventors:
Gene C. Robinson, G. Patrick Stahly
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: Sep 28, 1989
Inventors
Gene C. Robinson
G. Patrick Stahly
Assignee (at issue)
Ethyl 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.