Granted Patent
Utility
US 4,338,261 · App. 06/247,416
Process for the preparation of 1-naphthylamine-4,6-disulphonic acid and 1-naphthylamine-2,4,6-trisulphonic acid
Inventors:
Heinz U. Blank, Horst Behre, Hans W. Linden, Werner Mentzel
Patented Case
View Patent ↗
Granted: Jul 6, 1982
Filed: Mar 25, 1981
Inventors
Heinz U. Blank
Horst Behre
Hans W. Linden
Werner Mentzel
Assignee (at issue)
Bayer Aktiengesellschaft
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.