Patents by Inventor David M. Henson

David M. Henson 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).

  • Method and apparatus for photographic processing solution replenishment
    Patent number: 5439784
    Abstract: A method for replenishing an unstable photographic processing solution is disclosed, including the following replenisher solutions:(1) a color developer replenisher,(2) an oxidizing agent replenisher, and(3) a halide-containing seasoning replenisher (starter solution).The oxidizing agent is not removed from the developer/amplifier after use.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: August 8, 1995
    Assignee: Eastman Kodak Company
    Inventors: Andrew D. Grimsey, David M. Henson, Peter D. Marsden, Peter J. Twist
  • Filtration technique
    Patent number: 5437790
    Abstract: A method for increasing the filtration rate of a precipitate produced from a photographic effluent includes treating the effluent with hydrogen peroxide and an alkaline earth metal salt to form a precipitate and adding to the precipitate a diatomaceous earth filtering aid and then filtering the precipitate.
    Type: Grant
    Filed: November 16, 1994
    Date of Patent: August 1, 1995
    Assignee: Eastman Kodak Company
    Inventors: John R. Fyson, Martyn S. Glover, David M. Henson
  • Chemical reaction systems
    Patent number: 5353084
    Abstract: The invention provides a chemical reaction system and an apparatus exemplified by a photographic process wherein a photosensitive paper substrate is passed through a developing solution contained in a main tank and then through a replenisher tank. The replenisher tank in turn overflows back into the solution. This reduces the presence of unwanted by-products on the substrate. On leaving the replenishing solution the paper passes straight into an amplification tank, and thence into conventional bleach-fix or fixing solution.
    Type: Grant
    Filed: October 2, 1992
    Date of Patent: October 4, 1994
    Assignee: Eastman Kodak Company
    Inventors: Peter J. Twist, David M. Henson