Granted Patent
Utility
US 5,212,221 · App. 07/878,102
Stabilized phthalocyanine pigment compositions
Inventors:
Robert Langley, Michael McFarlane
Patented Case
View Patent ↗
Granted: May 18, 1993
Filed: May 4, 1992
Inventors
Robert Langley
Michael McFarlane
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.