Patents by Inventor John Kenneth Charles Kempster

John Kenneth Charles Kempster 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).

  • Patent number: 5747230
    Abstract: A photographic silver halide color print material comprising a support and yellow, magenta and cyan dye image forming layer units comprising at least one silver halide emulsion layer and at least one dye image-forming coupler which material contains a total silver halide coating weight less than 150 mg/m.sup.2 (as silver) and wherein the grain size (average volume in cubic microns) of the emulsion(s) is less than 1.0 (.mu.m).sup.3 in the yellow image forming unit and less than 0.125 (.mu.m).sup.3 in the magenta image forming unit and wherein each layer unit of the material has a dye image-forming efficiency (E) under conditions of use of above 30 where: ##EQU1## wherein the emulsion(s) of the cyan dye image forming layer unit have a silver coating weight less than 50 mg/m.sup.2, and an average grain size less than 0.064 (.mu.m).sup.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: May 5, 1998
    Assignee: Eastman Kodak Company
    Inventors: John Arthur Bee, John Kenneth Charles Kempster, Gareth Evans
  • Patent number: 5736306
    Abstract: Spectral properties of dye images produced from low silver halide coverage materials are improved by using dyes which are formed in the magenta, yellow and cyan image dye-forming units. These dyes have certain spectral characteristics, as determined by their unwanted absorptions, in combination with certain silver halide emulsion grain characteristics in each emulsion layer. In particular, reduction of unwanted absorptions can be achieved either with couplers per se which meet these characteristics or by the use of certain high-boiling solvents in the coupler dispersions at preferred levels.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: April 7, 1998
    Assignee: Eastman Kodak Company
    Inventors: Gareth Bryn Evans, John Kenneth Charles Kempster, Danuta Gibson