Patents by Inventor Eric Bertels

Eric Bertels 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).

  • Method of preparing light-sensitive silver halide emulsions and dispersions of photographically useful compounds
    Patent number: 5627019
    Abstract: A method is provided of preparing a light-sensitive silver halide emulsion or a dispersion of a photographically useful compound comprising the steps of precipitating silver halide or photographically useful compound in the presence of colloidal silica serving as a protective colloid, coagulation washing the precipitate formed and redispersing the silver halide or the photographically useful compound, characterised in that the coagulation takes place in the presence of hydroxy ethyl cellulose as, e.g., hydroxy ethyl cellulose, hydroxy propyl cellulose, methyl cellulose etc., as a polymer capable of forming hydrogen bridges with the silica, in an amount sufficient to form coagulable aggregates with the silica particles.
    Type: Grant
    Filed: August 31, 1995
    Date of Patent: May 6, 1997
    Assignee: AGFA-Gevaert, N.V.
    Inventors: Hubert Vandenabeele, Eric Bertels