Granted Patent
Utility
US 5,154,769 · App. 07/644,320
Process for production of black manganese/iron oxide pigment
Inventors:
Peter Kuske, Gunter Buxbaum
Patented Case
View Patent ↗
Granted: Oct 13, 1992
Filed: Jan 22, 1991
Inventors
Peter Kuske
Gunter Buxbaum
Assignee (at issue)
Bayer Aktiengesellschaft
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.