Granted Patent
Utility
US 4,889,689 · App. 07/264,597
Method of disinfecting a soft contact lens with a diethylene triamine penta(methylenephosphonic acid) stabilized hydrogen peroxide solution
Inventor:
Fupao Tsao
Patented Case
View Patent ↗
Granted: Dec 26, 1989
Filed: Oct 31, 1988
Inventor
Fupao Tsao
Assignee (at issue)
Ciba-Geigy
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.