Granted Patent
Utility
US 4,956,430 · App. 07/345,820
Process for preparing substantially pure high molecular weight vinyl lactam-quaternized acrylamide copolymers
Inventor:
Mohammed Tazi
Patented Case
View Patent ↗
Granted: Sep 11, 1990
Filed: May 1, 1989
Inventor
Mohammed Tazi
Assignee (at issue)
GAF Chemicals Corporation
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.