Granted Patent
Utility
US 5,601,663 · App. 08/605,405
Process for forming a black oxide on aluminum alloys and a solution therefor
Inventors:
Ravi Rungta, Robert Roy Ahrens, Mingguang Zhu
Patented Case
View Patent ↗
Granted: Feb 11, 1997
Filed: Feb 22, 1996
Inventors
Ravi Rungta
Robert Roy Ahrens
Mingguang Zhu
Assignee (at issue)
General Motors LLC
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.