Patents by Inventor Robert J. Opitz

Robert J. Opitz 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).

  • Synthesis of bis(phthalocyanylalumino)tetraphenyldisiloxanes
    Patent number: 5817805
    Abstract: A cyan pigment, bis(phthalocyanylalumino)tetraphenyldisiloxane is prepared in a single reaction mixture. A phthalonitrile is reacted at high temperature with an aluminum salt in the presence of an ammonia donor such as urea, in an inert, high boiling organic solvent. The resulting reaction product is cooled and without isolation, refluxed in an aqueous solution of a pyridine compound containing dichlorodiphenylsilane. The desired cyan pigment is then isolated.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: October 6, 1998
    Assignee: Eastman Kodak Company
    Inventors: William T. Gruenbaum, Chang K. Kim, Cataldo A. Magguilli, Robert J. Opitz
  • Fixer additives used in combination with iron complex based bleaches to prevent iron retention
    Patent number: 5508150
    Abstract: A method of processing an image wise exposed and developed silver halide photographic element comprising bleaching the photographic element in a bleaching or bleach-fixing solution containing as the primary bleaching agent a complex of ferric ion and a tridentate or a tetradentate ligand, and then processing the photographic element in a solution containing a chelating compound represented by Formula IHOOC(CH.sub.2).sub.m (X) ((CH.sub.2).sub.n COOH).sub.2 (I)whereX is N, or C--OH;n and m are independently 0, 1, or 2; andM is a cationic ion.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: April 16, 1996
    Assignee: Eastman Kodak Company
    Inventors: Mary E. Craver, Janet M. Huston, Robert J. Opitz