Granted Patent
Utility
US 4,550,069 · App. 06/619,468
Positive photoresist compositions with o-quinone diazide, novolak, and propylene glycol alkyl ether acetate
Inventor:
Thomas R. Pampalone
Patented Case
View Patent ↗
Granted: Oct 29, 1985
Filed: Jun 11, 1984
Inventor
Thomas R. Pampalone
Assignee (at issue)
American Hoechst 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.