Granted Patent
Utility
US 4,286,998 · App. 06/153,208
Light stable quinacridonequinone yellow pigment
Inventors:
Wilfried G. Holtje, George H. Senkler, Jr., Arthur J. Taggi
Patented Case
View Patent ↗
Granted: Sep 1, 1981
Filed: May 27, 1980
Inventors
Wilfried G. Holtje
George H. Senkler, Jr.
Arthur J. Taggi
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND COMPANY
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.