Patents by Inventor Benjamin S. Tennyson

Benjamin S. Tennyson 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).

  • Purification of aqueous dye solutions
    Patent number: 6153789
    Abstract: The present invention provides a method of purifying an aqueous dye solution having an aldehyde and/or ketone impurity including a step of reacting the impurity with a hydrazine derivative, forming a water-insoluble hydrazone compound. The hydrazone compound is then removed from the solution to form a dye having an increased purity.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: November 28, 2000
    Assignee: BASF Corporation
    Inventors: Kevin P. Cusack, Kwang Kim, Dennis L. Edie, Benjamin S. Tennyson