Granted Patent
Utility
US 4,940,783 · App. 07/238,637
Disazo containing diaminostilbene as diazo component and an aniline coupling component bearing a cationic alkyl ammonium group
Inventor:
Willy Stingelin
Patented Case
View Patent ↗
Granted: Jul 10, 1990
Filed: Aug 30, 1988
Inventor
Willy Stingelin
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.