Granted Patent
Utility
US 4,923,973 · App. 07/382,001
1:2 Cobalt complexes of disazo dyes
Inventor:
Alois Puntener
Patented Case
View Patent ↗
Granted: May 8, 1990
Filed: Jul 17, 1989
Inventor
Alois Puntener
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.