Granted Patent
Utility
US 4,278,601 · App. 06/093,488
Process for conditioning phthalocyanine pigment
Inventors:
Ian Robert Wheeler, George H. Robertson, David Ross McGregor
Patented Case
View Patent ↗
Granted: Jul 14, 1981
Filed: Nov 13, 1979
Inventors
Ian Robert Wheeler
George H. Robertson
David Ross McGregor
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.