Granted Patent
Utility
US 4,340,536 · App. 06/149,605
Chrome-complex dyes and the production and use thereof
Inventor:
Fabio Beffa
Patented Case
View Patent ↗
Granted: Jul 20, 1982
Filed: May 14, 1980
Inventor
Fabio Beffa
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.