Granted Patent
Utility
US 4,298,536 · App. 06/033,404
Process for the manufacture of 1,2-diaminoanthraquinone
Inventor:
Athanassios Tzikas
Patented Case
View Patent ↗
Granted: Nov 3, 1981
Filed: Apr 26, 1979
Inventor
Athanassios Tzikas
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.