Granted Patent
Utility
US 4,314,938 · App. 06/158,555
Iminoisoindolinone pigments containing phenylazoacetoacetyl-aminophenylene groups
Inventor:
Ernst Model
Patented Case
View Patent ↗
Granted: Feb 9, 1982
Filed: Jun 11, 1980
Inventor
Ernst Model
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.