Granted Patent
Utility
US 4,973,754 · App. 07/352,233
Preparation of bis(p-aminocumyl)benzenes
Inventor:
Simon M. Li
Patented Case
View Patent ↗
Granted: Nov 27, 1990
Filed: May 15, 1989
Inventor
Simon M. Li
Assignee (at issue)
SHELL OIL COMPANY
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.