Granted Patent
Utility
US 4,521,591 · App. 06/346,785
Oil-soluble disazo dyes and their use in color-photographic recording materials for the silver dye bleach process
Inventors:
Gerald Jan, John Lenoir
Patented Case
View Patent ↗
Granted: Jun 4, 1985
Filed: Feb 8, 1982
Inventors
Gerald Jan
John Lenoir
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.