Granted Patent
Utility
US 4,276,224 · App. 06/057,157
Anthraquinone sulphonamide compounds and preparation
Inventors:
Donald Richard Randell, Emyr Phillips
Patented Case
View Patent ↗
Granted: Jun 30, 1981
Filed: Jul 12, 1979
Inventors
Donald Richard Randell
Emyr Phillips
Assignee (at issue)
Ciba-Geigy
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.