Granted Patent
Utility
US 5,041,539 · App. 07/370,089
Preparation of aqueous concentrates of yellow azo and azoxystilbene dyes utilizing alkanolamine salts
Inventors:
Athanassios Tzikas, Paul Herzig, Jurgen Markert
Patented Case
View Patent ↗
Granted: Aug 20, 1991
Filed: Jun 19, 1989
Inventors
Athanassios Tzikas
Paul Herzig
Jurgen Markert
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.