Granted Patent
Utility
US 4,247,337 · App. 06/087,132
Copper phthalocyanine derivatives
Inventors:
Alexander M. Irvine, John B. Blackburn
Patented Case
View Patent ↗
Granted: Jan 27, 1981
Filed: Oct 22, 1979
Inventors
Alexander M. Irvine
John B. Blackburn
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.