Granted Patent
Utility
US 4,906,740 · App. 06/886,756
Monoazo dyes containing as the azo component A phenylsulfonylphenyl radical
Inventor:
Rudolf Hurter
Patented Case
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Granted: Mar 6, 1990
Filed: Jul 15, 1986
Inventor
Rudolf Hurter
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.