Patents by Inventor Charles Robert Barr

Charles Robert Barr 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: 4022616
    Abstract: A process is disclosed for producing a positive colored image in an imagewise exposed photographic element. The element is comprised of a support having coated thereon at least one layer of a hydrophilic colloid coating containing at least one light-sensitive silver halide and, in association with said silver halide, a substantially colorless, image dye-providing compound. The image dye-providing compound is reactive with oxidized color-forming reducing agent to yield a bleachable image dye. The process is comprised of the following steps: A silver image is developed in the imagewise exposed areas of the photographic element and a low level silver fog is formed in the remaining areas of the element. Image dye-providing compound is then converted to a bleachable image dye uniformly throughout the photographic element using the silver as a catalyst for a redox reaction of a color-forming reducing agent and a cobalt(III) complex amplifier oxidizing agent.
    Type: Grant
    Filed: March 1, 1976
    Date of Patent: May 10, 1977
    Assignee: Eastman Kodak Company
    Inventors: Charles Robert Barr, John Vincent Williams