Patents by Inventor Ludovicus P. Joly

Ludovicus P. Joly 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).

  • Process for the preparation of silver halide emulsions
    Patent number: 5017468
    Abstract: A method is disclosed for preparing silver halide emulsions useful in photography. Said method comprises the step of precipitating silver halide grains in an aqueous solution of peptizer initially and finally under pAg values suitable for forming cubic silver halide crystals characterized in that at least once during the precipitation stage the pAg is increased for at least 10 percent by weight of the total amount of silver salt used during the precipitation by at least 1.5 units to such value whereby the formation of octahedral crystals would occur if that value were to persist over the entire precipitation stage.Preferably the increase of the pAg value is brought about after precipitation of between ten and twenty percent of the total amount of silver halide to be precipitated.
    Type: Grant
    Filed: February 16, 1990
    Date of Patent: May 21, 1991
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Ludovicus P. Joly, Antonius A. Rutges