Patents by Inventor Robert E. Atwell

Robert E. Atwell 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).

  • Internally doped surface sensitized high chloride silver halide emulsions and photograhic elements and processes for their preparation
    Patent number: 4269927
    Abstract: This disclosure relates to high chloride silver halide emulsions and photographic elements containing silver halide grains which are internally doped with cadmium, lead, zinc or mixtures thereof in concentrations up to 7.times.10.sup.-5 mole/mole of silver halide.
    Type: Grant
    Filed: July 16, 1980
    Date of Patent: May 26, 1981
    Assignee: Eastman Kodak Company
    Inventor: Robert E. Atwell
  • Blended internal latent image emulsions, elements including such emulsions and processes for their preparation and use
    Patent number: 4035185
    Abstract: A photographic silver halide emulsion capable of forming on exposure an internal latent image can be formed having a desired characteristic curve by providing a first photographic silver halide emulsion comprised of silver halide grains internally sensitized with a combination of middle chalcogen and noble metal sensitizers capable of forming on exposure an internal latent image and blending therewith a second, higher contrast photographic silver halide emulsion comprised of silver halide grains internally sensitized with a relatively lower proportion of middle chalcogen to noble metal sensitization. Both the first and second photographic silver halide emulsions are sensitized with the same middle chalcogen and noble metal sensitizers.
    Type: Grant
    Filed: January 30, 1976
    Date of Patent: July 12, 1977
    Assignee: Eastman Kodak Company
    Inventors: Francis J. Evans, Robert E. Atwell