Patents by Inventor Hong Z. Kim

Hong Z. Kim 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: 4298681
    Abstract: An N,N, disubstituted p-phenylenediamine salt of a phosphoric acid selected from the group consisting of ortho-phosphoric acid, pyrophosphoric acid and polyphosphoric acid. Such a phosphate is incorporated as a color developing agent in a liquid packaged developer concentrate which subsequently is mixed with other materials contained in a multi-package receptacle and the mixture is diluted with water to form a color developer working solution (bath) for developing a colored film. The developer concentrate has the advantage that the color developing agent therein does not tend to deteriorate upon standing, as do present-day widely used commercial N,N, disubstituted p-phenylenediamine color developing agents in developer liquid concentrates, e.g.
    Type: Grant
    Filed: February 23, 1973
    Date of Patent: November 3, 1981
    Assignee: Philip A. Hunt Chemical Corp.
    Inventors: David K. Bulloch, Hong Z. Kim