Granted Patent
Utility
US 4,322,415 · App. 06/159,256
Stable concentrated liquid preparations of metal complex dyes
Inventors:
Heinz Abel, Paul Hugelshofer, Arthur Buhler
Patented Case
View Patent ↗
Granted: Mar 30, 1982
Filed: Jun 13, 1980
Inventors
Heinz Abel
Paul Hugelshofer
Arthur Buhler
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.