Granted Patent
Utility
US 4,326,021 · App. 06/233,411
Photographic negative material with at least one layer containing a desensitized silver halide emulsion
Inventors:
Rolf Steiger, Jean-Francois Reber
Patented Case
View Patent ↗
Granted: Apr 20, 1982
Filed: Feb 11, 1981
Inventors
Rolf Steiger
Jean-Francois Reber
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.