Patents by Inventor Paul S. Huyffer

Paul S. Huyffer 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).

  • Bis-indolyl phthalides and naphthalides
    Patent number: 4124592
    Abstract: This invention relates to indole phthalein indicator dyes including phthalides and naphthalides wherein one of the indol-3-yl radicals is substituted with a hydrogen-bonding group on a carbon atom adjacent to the nitrogen atom of the indole ring. In a preferred embodiment, one of the indol-3-yl radicals is substituted with a hydrogen-bonding group and the other indol-3-yl radical is substituted with a hydrogen-bonding group or with an electron-withdrawing group. These indicator dyes, especially those of the preferred embodiment, possess a relatively high pKa and a relatively broad absorption spectrum in the visible range.
    Type: Grant
    Filed: October 23, 1973
    Date of Patent: November 7, 1978
    Assignee: Polaroid Corporation
    Inventors: Stanley M. Bloom, Alan L. Borror, Paul S. Huyffer
  • Methoxymethoxy protected intermediates for photographic dyes
    Patent number: 4104269
    Abstract: This invention relates to compounds of the formula: ##STR1## wherein: X is methyl, methoxy, hydroxy, amino, chloro or carboxy;m is a positive integer from 1 to 2; andA is an alkyl radical having from 9-17 carbon atoms.The compounds of this invention are particularly useful in diffusion transfer photographic products and processes.
    Type: Grant
    Filed: February 28, 1977
    Date of Patent: August 1, 1978
    Assignee: Polaroid Corporation
    Inventor: Paul S. Huyffer
  • Intermediates for photographic dyes
    Patent number: 4035401
    Abstract: Compounds defined by the following general formula: ##STR1## wherein: X is methyl, methoxy, hydroxy, amino, chloro or carboxy;m is a positive integer from 1 to 2; andA is alkyl having from 9-17 carbon atoms.The compounds of this invention are particularly useful as intermediates for producing photographic dyes.
    Type: Grant
    Filed: August 22, 1972
    Date of Patent: July 12, 1977
    Assignee: Polaroid Corporation
    Inventor: Paul S. Huyffer
  • 3,3-Disubstituted phthalides and naphthalides
    Patent number: 3933849
    Abstract: This invention relates to a class of phthalein indicator dyes useful as optical filter agents in photographic processes to protect a selectively exposed photosensitive material from further exposure during processing in the presence of incident light. Such dyes comprise 3,3-disubstituted phthalides and 3,3-disubstituted naphthalides wherein one of said 3,3 substituents is a carbazol-3-yl radical and the other is an indol-3-yl radical possessing a hydrogen-bonding group substituted on a carbon atom adjacent to the heterocyclic N atom, both of said carbazolyl and indolyl radicals having hydrogen substituted on the heterocyclic N atom.
    Type: Grant
    Filed: April 26, 1974
    Date of Patent: January 20, 1976
    Assignee: Polaroid Corporation
    Inventor: Paul S. Huyffer