Patents by Inventor Gunther Mahlberg

Gunther Mahlberg 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).

  • Gradation variable black- and -white paper
    Patent number: 4987063
    Abstract: A gradation variable black-and-white paper containing only one light sensitive silver halide emulsion layer in which transfer of sensitization is prevented may be obtained by sensitization with at least one compound corresponding to the following formula ##STR1## in which at least one of the groups R.sub.1, R.sub.5 or R.sub.6 is halogen.
    Type: Grant
    Filed: November 10, 1988
    Date of Patent: January 22, 1991
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Helmut Kampfer, Walter Patzold, Gunther Mahlberg
  • Stabilization of a photographically produced silver image using an amino-1,2,4-triazole
    Patent number: 4760015
    Abstract: Photographically produced black-and-white images (silver images) are stabilized against subsequent destruction of the silver image, in particular against the occurrence of so-called microspot defects, by treatment of the finished silver image with an aqueous after-treatment bath containing an amino-1,2,4-triazole.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: July 26, 1988
    Assignee: Agfa Gevaert Aktiengesellschaft
    Inventors: Werner Berthold, Gunther Mahlberg, Paul Marx, Hans hlschlager
  • Color photographic recording material containing a silver halide emulsion and a process for its production
    Patent number: 4705747
    Abstract: Improved silver halide emulsions are obtained by the combined use of an iridium compound and an imidazole before termination of crystal growth.
    Type: Grant
    Filed: February 24, 1986
    Date of Patent: November 10, 1987
    Assignee: Agfa Gevaert Aktiengesellschaft
    Inventors: Sieghart Klotzer, Bruno Mucke, Gunther Mahlberg, Manfred Becker