Granted Patent
Utility
US 4,298,398 · App. 06/181,958
Process for converting premilled crude quinacridone to pigmentary form
Inventor:
Patrick H. Fitzgerald
Patented Case
View Patent ↗
Granted: Nov 3, 1981
Filed: Aug 28, 1980
Inventor
Patrick H. Fitzgerald
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.