Granted Patent
Utility
US 4,560,639 · App. 06/528,036
Reusable phototransparency image forming tools for direct contact printing
Inventor:
Donald F. Sullivan
Patented Case
View Patent ↗
Granted: Dec 24, 1985
Filed: Aug 31, 1983
Inventor
Donald F. Sullivan
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.