Patents by Inventor Norbert Armbrecht

Norbert Armbrecht 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).

  • Patent number: 4492653
    Abstract: Water soluble trisazo dyestuffs of the formula ##STR1## in which A is 1-amino-8-naphthol-3,6-disulfonic acid or 1-amino-8-naphthol-4,6-disulfonic acid, or a mixture of these two compounds, and B is 1-(3'- or 4'-aminophenyl)-3-methyl-5-pyrazolone, a process for their manufacture by diazotizing component A and coupling it with 3,3'-dihydroxy-diphenylamine to give a monoazo dyestuff, reacting this dyestuff with diazotized component B to give a disazo dyestuff, and converting this dyestuff to the trisazo dyestuff by uniting it with diazotized 4-nitro-4'-amino-diphenylamine-2-sulfonic acid, or by operating as described while, however, changing the sequence of reaction of component B and 4-nitro-4'-amino-diphenylamine-2-sulfonic acid, and use of these dyestuffs for the dyeing of leather and fur.
    Type: Grant
    Filed: August 23, 1982
    Date of Patent: January 8, 1985
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Karl Sommer, Norbert Armbrecht
  • Patent number: 4485042
    Abstract: Leathers can be advantageously dyed with water-soluble polyazo dyestuffs having, in the form of the free acid, the formula ##STR1## wherein A is a member of the benzene, naphthalene or heterocyclic series;B has the formula ##STR2## n is the number 1 or 2; m is a number from 1 to 4;X is hydroxyl or amino;Y is hydroxyl or amino but X differs from Y;Z is hydroxyl or amino unsubstituted or substituted by alkyl having 1 to 4 carbon atoms, alkanoyl having 1 to 4 carbon atoms or by a moiety of the formula ##STR3## R.sup.1 is hydrogen, alkyl having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms or alkoxyalkoxy having 3 to 7 carbon atoms; andR.sup.2 and R.sup.3 independently of one another are each hydrogen or alkyl having 1 to 4 carbon atoms.
    Type: Grant
    Filed: August 20, 1982
    Date of Patent: November 27, 1984
    Assignee: Cassella Aktiengesellschaft
    Inventors: Norbert Armbrecht, Wolfgang Bauer, Joachim Ribka