Granted Patent
Utility
US 4,431,721 · App. 06/390,467
Use of perylene pigments for photoelectrophoretic imaging
Inventors:
Max Jost, Werner Sieber
Patented Case
View Patent ↗
Granted: Feb 14, 1984
Filed: Jun 21, 1982
Inventors
Max Jost
Werner Sieber
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.