Patents by Inventor Mark A. Whitson

Mark A. Whitson 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).

  • Attachment of gelatin-grafted plymer particles to pre-precipitated silver halide grains
    Patent number: 5543283
    Abstract: The invention describes silver halide packet emulsion grains or crystals that are conventionally precipitated using gelatin of a given isoelectric pH, surrounded by a layer of gelatin-grafted-polymer particles wherein the grafted gelatin has a different isoelectric pH and the said gelatin-grafted-polymer particles are optionally chemically bonded to the gelatin surrounding the silver halide microcrystals. Such packet emulsions can form the basis for a mixed-packet color photographic system.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: August 6, 1996
    Assignee: Eastman Kodak Company
    Inventors: Mark A. Whitson, John D. Lewis, Tienteh Chen, Thomas J. Dannhauser, Pranab Bagchi
  • Gelatin-grafted-polymer particles as peptizer for silver halide emulsions
    Patent number: 5503972
    Abstract: This invention describes the use of gelatin-grafted-polymer particles as peptizers for the preparation of silver halide photographic emulsions, whereby the gelatin-grafted-polymer particles remain attached to the AgX crystals after preparation of the emulsions. In an embodiment of this invention, the core polymer particles are loaded with photographically useful agents. When the photographic agent is a dye-forming coupler, multicolor mixed-packet systems can be constructed using the packet emulsions prepared in the manner of this invention.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: April 2, 1996
    Assignee: Eastman Kodak Company
    Inventors: John D. Lewis, Mark A. Whitson, Thomas J. Dannhauser, Tienteh Chen, Pranab Bagchi
  • Gelatin-grafted-polymer particles as peptizer for silver halide emulsions
    Patent number: 5441865
    Abstract: This invention describes the use of gelatin-grafted-polymer particles as peptizers for the preparation of silver halide photographic emulsions, whereby the gelatin-grafted-polymer particles remain attached to the AgX crystals after preparation of the emulsions. In an embodiment of this invention, the core polymer particles are loaded with photographically useful agents. When the photographic agent is a dye-forming coupler, multicolor mixed-packet systems can be constructed using the packet emulsions prepared in the manner of this invention.
    Type: Grant
    Filed: January 7, 1993
    Date of Patent: August 15, 1995
    Assignee: Eastman Kodak Company
    Inventors: John D. Lewis, Mark A. Whitson, Thomas J. Dannhauser, Tienteh Chen, Pranab Bagchi
  • Attachment of gelatin-grafted polymer particles to pre-precipitated silver halide grains
    Patent number: 5399480
    Abstract: The invention describes silver halide packet emulsion grains or crystals that are conventionally precipitated using gelatin of a given isoelectric pH, surrounded by a layer of gelatin-grafted-polymer particles wherein the grafted gelatin has a different isoelectric pH and the said gelatin-grafted-polymer particles are optionally chemically bonded to the gelatin surrounding the silver halide microcrystals. Such packet emulsions can form the basis for a mixed-packet color photographic system.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: March 21, 1995
    Assignee: Eastman Kodak Company
    Inventors: Mark A. Whitson, John D. Lewis, Tienteh Chen, Thomas J. Dannhauser, Pranab Bagchi
  • Silver halide photographic emulsions precipitated in the presence of organic dichalcogenides
    Patent number: 5364754
    Abstract: This invention provides a method of preparing a silver halide photographic emulsion which comprises adding to the silver halide emulsion before or during precipitation a non-labile chalcogen compound represented by Formula I:R.sup.1 --X.sup.1 --X.sup.2 --R.sup.2 (Formula I)It further provides a silver halide photographic emulsion prepared by the above method.
    Type: Grant
    Filed: October 29, 1992
    Date of Patent: November 15, 1994
    Assignee: Eastman Kodak Company
    Inventors: Sang H. Kim, Anthony Adin, Richard E. Beal, Jerzy A. Budz, Wai K. Lam, Mark A. Whitson