Patents by Inventor Leonard E. Lowrie

Leonard E. Lowrie 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).

  • Interstage treatment of mechanical pulp
    Patent number: 4718980
    Abstract: A two-stage pulp refining system in which the fibrous material from the first stage refiner is in contact with an alkaline bleaching solution between refining stages at a temperature of 32.degree.-96.degree. C. and at a consistency of 15-25% on an oven dry basis. The material is then diluted and then pressed to a consistency of at least 20% and passes through the second stage refiner.
    Type: Grant
    Filed: December 30, 1985
    Date of Patent: January 12, 1988
    Assignee: Weyerhaeuser Company
    Inventors: Leonard E. Lowrie, William L. Duncan