Granted Patent
Utility
US 4,608,435 · App. 06/489,360
Benzo-1,4-quinones
Inventor:
Frederick H. Howell
Patented Case
View Patent ↗
Granted: Aug 26, 1986
Filed: Apr 28, 1983
Inventor
Frederick H. Howell
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.