Granted Patent
Utility
US 4,657,554 · App. 06/736,913
Water-soluble azaphthalocyanines and their use as photoactivators in bleaching
Inventors:
Gerhard Reinert, Gerd Holzle, Gregor Graf
Patented Case
View Patent ↗
Granted: Apr 14, 1987
Filed: May 22, 1985
Inventors
Gerhard Reinert
Gerd Holzle
Gregor Graf
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.