Granted Patent
Utility
US 4,401,795 · App. 06/223,441
Polymeric polyelectrolytes
Inventors:
Daniel F. Herman, Uno Kruse
Patented Case
View Patent ↗
Granted: Aug 30, 1983
Filed: Jan 8, 1981
Inventors
Daniel F. Herman
Uno Kruse
Assignee (at issue)
NL Industries, Inc.
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.