Granted Patent
Utility
US 4,263,151 · App. 06/063,228
Oil solutions and/or dispersions of hydrated chromium oxides
Inventors:
William J. Cheng, Donald M. Leiendecker
Patented Case
View Patent ↗
Granted: Apr 21, 1981
Filed: Aug 3, 1979
Inventors
William J. Cheng
Donald M. Leiendecker
Assignee (at issue)
Petrolite 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.