Granted Patent
Utility
US 4,394,315 · App. 06/229,061
Method for manufacturing p- and o-benzoquinone derivatives
Inventors:
Fumio Ishii, Kenichi Kishi
Patented Case
View Patent ↗
Granted: Jul 19, 1983
Filed: Jan 28, 1981
Inventors
Fumio Ishii
Kenichi Kishi
Assignee (at issue)
Konishiroku Photo Industry Co., 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.