Granted Patent
Utility
US 5,073,277 · App. 07/558,974
Lubricants containing ammonium salts of methylphosphonic acid
Inventors:
Hermann O. Wirth, Klaus Muller
Patented Case
View Patent ↗
Granted: Dec 17, 1991
Filed: Jul 26, 1990
Inventors
Hermann O. Wirth
Klaus Muller
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.