Granted Patent
Utility
US 5,690,699 · App. 08/606,899
Azo dye mixtures and their use
Inventors:
Klaus Hannemann, Urs Lehmann
Patented Case
View Patent ↗
Granted: Nov 25, 1997
Filed: Feb 26, 1996
Inventors
Klaus Hannemann
Urs Lehmann
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.