Granted Patent
Utility
US 4,868,245 · App. 07/079,380
Modified block copolymers having carboxyl groups grafted on the alkenyl arene blocks
Inventors:
Lorelle A. Pottick, Carl L. Willis, William P. Gergen, Robert G. Lutz
Patented Case
View Patent ↗
Granted: Sep 19, 1989
Filed: Jul 30, 1987
Inventors
Lorelle A. Pottick
Carl L. Willis
William P. Gergen
Robert G. Lutz
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.