Granted Patent
Utility
US 4,613,669 · App. 06/512,074
Preparation of 1,4-diketopyrrolo-[3,4-c]pyrroles
Inventors:
Luigi Cassar, Abul Iqbal, Alain C. Rochat
Patented Case
View Patent ↗
Granted: Sep 23, 1986
Filed: Jul 8, 1983
Inventors
Luigi Cassar
Abul Iqbal
Alain C. Rochat
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.