Patents by Inventor Gerhard Hanika

Gerhard Hanika 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).

  • Oxazine dyes, their preparation and the use thereof
    Patent number: 5917035
    Abstract: The compounds of formula ##STR1## wherein the substituents are as defined in the claims, are suitable for dyeing or printing, inter alia, polyacrylonitrile and acid-modified polyester fibers, and can furthermore be converted by anion exchange into a physical form suitable for liquid formulations.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: June 29, 1999
    Assignee: Ciba Specialty Chemicals Corporation
    Inventors: Hanspeter Birri, Gerhard Hanika, Alex Nicopoulos
  • Process for the preparation of highly concentrated solutions of cationic azo dyes
    Patent number: 5284939
    Abstract: There is described a process for the preparation of highly concentrated aqueous solutions of specific cationic azo dyes. The solutions are prepared by diazotising a diazo component in a solution which contains sulfuric acid, coupling the diazotised component to a coupling component, treating the resultant azo dye with a bicarbonate, and converting the dye bicarbonate with an organic acid into the dye salt of said acid.
    Type: Grant
    Filed: May 14, 1992
    Date of Patent: February 8, 1994
    Assignee: Ciba-Geigy Corporation
    Inventors: Alex Nicopoulos, Hanspeter Birri, Gerhard Hanika