Patents by Inventor David W. Woodward

David W. Woodward 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).

  • Photographic silver halide element with opaque backing layer
    Patent number: 4211837
    Abstract: Removable opaque backing layers for photographic silver halide elements are described. The opaque backing layer contains carbon black and a scavenging agent for impurities of the carbon black selected from fine-rain photosensitive silver halides, silver nitrate, and halides of iron, zinc and mercury. The scavenger prevents the impurities from fogging the photographic silver halide emulsion layers of the elements.
    Type: Grant
    Filed: October 1, 1976
    Date of Patent: July 8, 1980
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ralph K. Blake, James G. Morgan, David W. Woodward