Patents by Inventor Donald R. Dimmel

Donald R. Dimmel 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).

  • Method for the delignification of lignocellulosic material by adding a dialkyl substituted octahydroanthraquinone
    Patent number: 6156155
    Abstract: The present invention provides a method for the synthesis of substituted octahydroanthraquinones and substituted anthraquinones which are effective for pulping of lignocellulosics.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: December 5, 2000
    Assignee: Institute of Paper Science and Technology, Inc.
    Inventor: Donald R. Dimmel
  • Lignin derived quinonic compound mixtures useful for the delignification of cellulosic materials
    Patent number: 5049236
    Abstract: A method for the preparation of a mixture of fused ring quinone type compounds from lignin and lignin-derived substances. The mixture of fused ring quinone compounds has been found useful in the wood pulping process as an accelerator in the degradation and separation of wood lignin from the other principal wood constituents, cellulose and hemicellulose.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: September 17, 1991
    Assignee: Institute of Paper Science and Technology, Inc.
    Inventors: Donald R. Dimmel, John C. Wozniak
  • Method for the delignification of wood pulp utilizing fused ring quinone compounds prepared from lignin or lignin derived substances
    Patent number: 5002634
    Abstract: A method for the preparation of a mixture of fused ring quinone type compounds from lignin and lignin derived substances. The mixture of fused ring quinone compounds has been found useful in the wood pulping process as an accelerator in the degradation and separation of wood lignin from the other principal wood constituents, cellulose and hemicellulose.
    Type: Grant
    Filed: September 25, 1989
    Date of Patent: March 26, 1991
    Assignee: Institute of Paper Science and Technology, Inc.
    Inventors: Donald R. Dimmel, John C. Wozniak