Granted Patent
Utility
US 4,847,374 · App. 07/145,430
Process for the manufacture of N,N-(Dibenzohexatrienylene)ureas
Inventors:
Georg Acklin, Ernst Aufderhaar, Günter Kaupp, Bernhard Raz, Ulrich Vogel
Patented Case
View Patent ↗
Granted: Jul 11, 1989
Filed: Jan 19, 1988
Inventors
Georg Acklin
Ernst Aufderhaar
Günter Kaupp
Bernhard Raz
Ulrich Vogel
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.