Patents by Inventor Paul Kniel

Paul Kniel 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).

  • Process for producing 1-amino-4-hydroxy-anthraquinones
    Patent number: 4485043
    Abstract: 1-Amino-4-hydroxy-2-phenoxy- or -2-alkoxyanthraquinones are obtained by reaction of a 1-amino-2-halo-4-hydroxyanthraquinone with an alcohol or phenol. The reaction is performed in an organic solvent in the presence of an alkaline-acting agent and a phase-transfer catalyst.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: November 27, 1984
    Assignee: Ciba-Geigy AG
    Inventor: Paul Kniel