Patents by Inventor Michael E. Dale

Michael E. Dale 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).

  • Tetra-aza indene compounds
    Patent number: 4728601
    Abstract: Tetra-aza indene compounds of the formula ##STR1## wherein R.sub.1 is alkyl or a ring system and R.sub.2 and R.sub.3 are hydrogen or alkyl.These compounds are of use as image toners in photographic materials.
    Type: Grant
    Filed: April 1, 1986
    Date of Patent: March 1, 1988
    Assignee: Ciba-Geigy AG
    Inventors: David Rowland, Michael E. Dale, Geoffrey E. Ficken, William E. Long, Andrew W. Yates