Granted Patent
Utility
US 5,451,270 · App. 08/307,970
Composition for a method of monitoring dried-in-place non-chrome polyacrylamide based treatments for metals
Inventors:
Jiangbo Ouyang, William L. Harpel
Patented Case
View Patent ↗
Granted: Sep 19, 1995
Filed: Sep 16, 1994
Inventors
Jiangbo Ouyang
William L. Harpel
Assignee (at issue)
Betz Laboratories, 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.