Patents by Inventor Stephen A. Walkden

Stephen A. Walkden 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).

  • Sizing pulp
    Patent number: 4927496
    Abstract: Increased resistance of the cut edges of liquid packaging board to penetration by hot hydrogen peroxide is obtained by adding an aqueous emulsion of ketene dimer, cationic rosin size and insolubilizing agent either separately or in preblended form to the aqueous pulp slurry at a neutral to alkaline pH.
    Type: Grant
    Filed: May 25, 1988
    Date of Patent: May 22, 1990
    Assignee: Hercules Incorporated
    Inventor: Stephen A. Walkden