Granted Patent
Utility
US 5,007,941 · App. 07/454,499
Process for dyeing leather: aqueous bath containing mixture of carbon black and acid dye, direct dye or metal complex dye
Inventors:
Bruno Martinelli, Markus Ghezzi, Gunter Streicher
Patented Case
View Patent ↗
Granted: Apr 16, 1991
Filed: Dec 21, 1989
Inventors
Bruno Martinelli
Markus Ghezzi
Gunter Streicher
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.