Granted Patent
Utility
US 4,904,767 · App. 07/068,815
Asymmetric 1:2-chrome complexes of benzene-azo-naphthalene/naphthalene-azo-naphthalene acid dyes for leather
Inventors:
Fabio Beffa, Alois Puntener, Peter Loew
Patented Case
View Patent ↗
Granted: Feb 27, 1990
Filed: Jun 29, 1987
Inventors
Fabio Beffa
Alois Puntener
Peter Loew
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.