Patents by Inventor Renaat Frans Heylen

Renaat Frans Heylen 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).

  • Hardening fixer for photographic silver halide material
    Patent number: 4046570
    Abstract: A hardening fiber composition for use in the processing of photographic silver halide elements is described which contains a 1-hydroxy-alkylidene diphosphonic acid the alkylidene group of which contains from 2 to 5 C-atoms.
    Type: Grant
    Filed: May 27, 1976
    Date of Patent: September 6, 1977
    Assignee: AGFA-GEVAERT N.V.
    Inventors: Marcel Robert Fierens, Renaat Frans Heylen