Granted Patent
Utility
US 5,250,274 · App. 07/824,682
Process for the production of sodium dichromate
Inventors:
Norbert Lonhoff, Bernhard Spreckelmeyer, Hans-Dieter Block, Rainer Weber, Jost Halstenberg, Bernd Rosenow
Patented Case
View Patent ↗
Granted: Oct 5, 1993
Filed: Jan 21, 1992
Inventors
Norbert Lonhoff
Bernhard Spreckelmeyer
Hans-Dieter Block
Rainer Weber
Jost Halstenberg
Bernd Rosenow
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.