Granted Patent
Utility
US 5,502,091 · App. 08/202,417
Enhancement of paper dry strength by anionic and cationic guar combination
Inventor:
Sunil P. Dasgupta
Patented Case
View Patent ↗
Granted: Mar 26, 1996
Filed: Feb 28, 1994
Inventor
Sunil P. Dasgupta
Assignee (at issue)
HERCULES LLC
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.