Granted Patent
Utility
US 4,631,093 · App. 06/635,056
Chromate free method of treating metal substrates to impart corrosion resistance and color to the substrate surface
Inventor:
Alex Etemovich
Patented Case
View Patent ↗
Granted: Dec 23, 1986
Filed: Jul 27, 1984
Inventor
Alex Etemovich
Assignee (at issue)
TRE Corporation
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.