Patents by Inventor Hans R. von Tobel

Hans R. von Tobel 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).

  • Disazo and trisazo compounds having a 3-pyridinium or substituted pyridinium-4-methyl-6-hydroxypyridone-2 coupling component radical
    Patent number: 4213897
    Abstract: Sulfo group-free basic disazo and trisazo dyes of the formula ##STR1## wherein R is hydrogen; unsubstituted C.sub.1-4 alkyl; C.sub.2-4 -alkyl monosubstituted by hydroxy, the hydroxy being on other than the .alpha.-carbon atom; di-(C.sub.1-4 alkyl)amino or --CH.sub.2).sub.n Ko,R.sub.1 is hydrogen, C.sub.1-4 alkyl, C.sub.1-4 hydroxyalkyl or C.sub.1-4 alkoxy,n is 2 or 3,Ko is --N(CH.sub.3).sub.2, --N.sup..sym. (CH.sub.3).sub.3 A.sup..crclbar., --N.sup..sym. (CH.sub.3).sub.2 CH.sub.2 CH.sub.2 OH A.sup..crclbar. or ##STR2## each A.sup..crclbar. is an anion, Zo is a direct bond or a bridging group, andKx is a radical of a coupling component of the pyrazolone-5,5-aminopyrazole, .beta.-naphthol, .alpha.-naphthol, aniline, phenol or acetoacetylphenylamide series or the radical of barbituric acid, dimedone or a dimedone carboxylic acid ester,which compounds, where Kx is a radical of a coupling component of the pyrazolone-5,5-aminopyrazole, .beta.-naphthol, .alpha.
    Type: Grant
    Filed: March 8, 1978
    Date of Patent: July 22, 1980
    Assignee: Sandoz Ltd.
    Inventors: Helmut Moser, Hans R. von Tobel