Granted Patent
Utility
US 4,547,575 · App. 06/467,541
Vat dyes obtainable by bromination of dibenzanthrone and reaction with 1-aminoanthraquinone
Inventor:
Athanassios Tzikas
Patented Case
View Patent ↗
Granted: Oct 15, 1985
Filed: Feb 17, 1983
Inventor
Athanassios Tzikas
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.