Granted Patent
Utility
US 4,824,601 · App. 07/144,596
Liquid antioxidant produced by alkylating diphenylamine with a molar excess of diisobutylene
Inventor:
Janet FRANKLIN
Patented Case
View Patent ↗
Granted: Apr 25, 1989
Filed: Jan 11, 1988
Inventor
Janet FRANKLIN
Assignee (at issue)
Ciba-Geigy
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.