Granted Patent
Utility
US 5,319,081 · App. 08/011,934
Substituted N-thiomethyl phenothiazines as lubricant stabilizers
Inventor:
John D. Spivack
Patented Case
View Patent ↗
Granted: Jun 7, 1994
Filed: Feb 1, 1993
Inventor
John D. Spivack
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.