Granted Patent
Utility
US 4,719,167 · App. 06/825,902
Positive photoresist composition with 1,2 naphthoquinone diazide and novolak resin condensed from mixture of m-cresol, p-cresol, and 2,5-xylenol with formaldehyde
Inventors:
Konoe Miura, Tameichi Ochiai, Yasuhiro Kameyama
Patented Case
View Patent ↗
Granted: Jan 12, 1988
Filed: Feb 4, 1986
Inventors
Konoe Miura
Tameichi Ochiai
Yasuhiro Kameyama
Assignee (at issue)
Mitsubishi Chemical Industries, Ltd.
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.