Granted Patent
Utility
US 4,895,663 · App. 07/220,194
Water treatment polymers and methods of use thereof
Inventor:
Fu Chen
Patented Case
View Patent ↗
Granted: Jan 23, 1990
Filed: Jul 18, 1988
Inventor
Fu Chen
Assignee (at issue)
Betz Laboratories, 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.