Granted Patent
Utility
US 4,292,391 · App. 06/119,296
Silver halide development accelerators
Inventor:
Joseph D. Overman
Patented Case
View Patent ↗
Granted: Sep 29, 1981
Filed: Feb 6, 1980
Inventor
Joseph D. Overman
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND COMPANY
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.