Patents by Inventor Walter Sieber

Walter Sieber has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Mixtures of azo dyes for navy to black hues
    Patent number: 5431699
    Abstract: Dye mixtures containa) one or more azo dyes of the formula I ##STR1## where Y.sup.1 is hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.4 -alkoxy or unsubstituted or substituted C.sub.1 -C.sub.8 -alkanoylamino or C.sub.3 - or C.sub.4 -alkenylamino orY.sup.2 and Y.sup.3 are each hydrogen or unsubstituted or substituted C.sub.1 -C.sub.6 -alkylb) the azo dye of the formula II ##STR2## where L is allyl which may be partially replaced by or may furthermore be hydrogen andc) optionally, an azo dye of the formula III and/or IV as described in the specification.
    Type: Grant
    Filed: January 28, 1994
    Date of Patent: July 11, 1995
    Assignee: BASF Aktiengesellschaft
    Inventors: Arno Lange, Uwe Nahr, Walter Sieber, Volker Walther