Granted Patent
Utility
US 4,889,769 · App. 07/032,234
Method of producing matte precious metal decorations
Inventors:
Marion Lotze, Peter Kleinschmit
Patented Case
View Patent ↗
Granted: Dec 26, 1989
Filed: Mar 31, 1987
Inventors
Marion Lotze
Peter Kleinschmit
Assignee (at issue)
Degussa AG
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.