Granted Patent
Utility
US 5,693,371 · App. 08/734,429
Method for forming chromium-free conversion coating
Inventors:
Edward A. Rodzewich, Jiangbo Ouyang, Joseph E. Murphy
Patented Case
View Patent ↗
Granted: Dec 2, 1997
Filed: Oct 16, 1996
Inventors
Edward A. Rodzewich
Jiangbo Ouyang
Joseph E. Murphy
Assignee (at issue)
Betzdearborn, Inc.
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.