Granted Patent
Utility
US 5,368,641 · App. 07/995,354
Modified 2,9-dimethylquinacridone pigments, process for their manufacture and a method for pigmenting or lacquer systems with these pigments
Inventors:
Erwin Dietz, Adolf Kroh
Patented Case
View Patent ↗
Granted: Nov 29, 1994
Filed: Dec 22, 1992
Inventors
Erwin Dietz
Adolf Kroh
Assignee (at issue)
Hoechst GmbH
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.