Granted Patent
Utility
US 5,069,798 · App. 07/451,484
Control of scale in aqueous systems using certain phosphonomethyl amines
Inventors:
Chih M. Hwa, John A. Kelly, Janet Neton, Patricia Scanlon, Roger R. Gaudette
Patented Case
View Patent ↗
Granted: Dec 3, 1991
Filed: Dec 15, 1989
Inventors
Chih M. Hwa
John A. Kelly
Janet Neton
Patricia Scanlon
Roger R. Gaudette
Assignee (at issue)
W.R. Grace & Co. Conn.
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.