Granted Patent
Utility
US 6,217,709 · App. 09/207,895
Cationic starch/cationic galactomannan gum blends as strength and drainage aids
Inventor:
Keith Edward Burnfield
Patented Case
View Patent ↗
Granted: Apr 17, 2001
Filed: Nov 23, 1998
Inventor
Keith Edward Burnfield
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.