Granted Patent
Utility
US 5,663,326 · App. 08/529,822
Mixtures of isomeric substituted phthalocyanines, and process for their preparation
Inventor:
Heinz Wolleb
Patented Case
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Granted: Sep 2, 1997
Filed: Sep 18, 1995
Inventor
Heinz Wolleb
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.