Granted Patent
Utility
US 4,625,027 · App. 06/542,226
Bisquinazolines useful in color former systems
Inventors:
Rudolf Zink, Ian J. Fletcher
Patented Case
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Granted: Nov 25, 1986
Filed: Oct 14, 1983
Inventors
Rudolf Zink
Ian J. Fletcher
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.