Granted Patent
Utility
US 6,503,315 · App. 09/718,272
Process for producing iron oxide pigments
Inventors:
Norbert Etzenbach, Kai Butje
Patented Case
View Patent ↗
Granted: Jan 7, 2003
Filed: Nov 22, 2000
Inventors
Norbert Etzenbach
Kai Butje
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.