Patents by Inventor John D. Withenshaw

John D. Withenshaw 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).

  • Patent number: 5433881
    Abstract: An improvement in the process of granulating bleach activator using an organic binder selected from starch and cellulose derivatives polyacrylates, polymaleates and polyvinyl pyrrolidone, the process comprising dry mixing particulate activator and at least a portion of the binder in particulate form and then moistening the mixture with a granulating liquid, comprises using as granulating liquid an aqueous solution of a granulating aid which is a sequestrant optionally combined with a water-soluble inorganic salt. The granules are then dried. The product has improved activity in laundry detergents especially in low temperature wash and cold fill conditions.
    Type: Grant
    Filed: December 2, 1992
    Date of Patent: July 18, 1995
    Assignee: Warwick International Group Limited
    Inventors: John Townend, Anthony J. Gradwell, John D. Withenshaw
  • Patent number: 4921631
    Abstract: An extruded particulate body comprises a binder, usually having a melting point in the range 20.degree.-80.degree. C., with particulate bleach activator and particulate water-soluble disintegration aid substantially uniformly distributed throughout the body. The bleach activator is a mixture of a relatively non-surface active bleach activator, preferably tetra-acetylethylene diamine, and a relatively surface active activator, usually a C.sub.6-10 alkanoyloxy benzene sulphonate. The disintegration aid is usually a bleach stabilizor preferably a phosphonic acid or salt thereof. The extruded bodies are for incorporation into a particulate detergent formulation which contains a peroxy bleach component.
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: May 1, 1990
    Assignee: Warwick International Limited
    Inventors: Anthony J. Gradwell, John D. Withenshaw