Granted Patent
Utility
US 6,025,508 · App. 09/322,820
Preparation of quinonediimines from phenylenediamines using oxygen and a metal or metal salt catalyst
Inventors:
Jayant S. Lodaya, Raymond Anton Lohr, Jr., Donald L. Fields, Jr.
Patented Case
View Patent ↗
Granted: Feb 15, 2000
Filed: May 28, 1999
Inventors
Jayant S. Lodaya
Raymond Anton Lohr, Jr.
Donald L. Fields, Jr.
Assignee (at issue)
Flexsys America L.P.
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.