Patents by Inventor Klaus Ruf

Klaus Ruf 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).

  • Pigments having improved colouristic properties and process for their preparation
    Publication number: 20030127023
    Abstract: The invention relates to a process for preparing pigments, which comprises
    Type: Application
    Filed: December 4, 2002
    Publication date: July 10, 2003
    Inventors: Yves Grandidier, Albert Riegler, Klaus Ruf, Urs Schlatter, Takashi Deno
  • Crimson-colored pigment composition and the utilization thereof
    Patent number: 6494947
    Abstract: The invention relates to crimson-colored pigment mixtures comprising 1,4-diketo-2,5-dihydro-3,6-diarylpyrrolo[3,4c]pyrrole and quinacridone pigments in separate crystalline phases, having a high tinctorial strength combined with other excellent application properties. The pigments according to the invention can be used in printing inks, especially in printing inks for polychromatic printed products. A substantial constituent of the pigment mixtures according to the invention is 1,4-diketo-2,5-dihydro-3,6-di(4′-chlorophenyl)pyrrolo[3,4c]pyrrole or 2,9-dichloroquinacridone, which are subjected to kneading with a crystalline inorganic salt and a neutral organic liquid. The invention also relates to a process for the preparation of such pigment compositions, the use thereof in the production of printing inks, and such printing inks themselves.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: December 17, 2002
    Assignee: Ciba Specialty Chemicals Corporation
    Inventors: Hanspeter Hauser, Yves Grandidier, Klaus Ruf
  • Process for the preparation of bisazo pigments in halogen-free solvents
    Patent number: 5185435
    Abstract: The present invention relates to the preparation of bisazo pigments by reaction (a) of 2 mol of an azocarbonyl chloride of the formula ##STR1## with 1 mol of a diamine of the formula ##STR2## by reaction (b) of one mole of a bis(azocarbonyl chloride) of the formula ##STR3## with 2 mol of an amine of the formula ##STR4## which comprises carrying out the reactions (a) or (b) in the presence of 1,2,3-trimethylbenzene or anisole as the solvent.
    Type: Grant
    Filed: January 30, 1992
    Date of Patent: February 9, 1993
    Assignee: Ciba-Geigy Corporation
    Inventors: Klaus Ruf, Bilge Gulec, Michael Reisinger, Werner Surber