Patents by Inventor Warren Hewertson

Warren Hewertson 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).

  • 2,5-Dimethyl-2,4-hexadiene production
    Patent number: 4130598
    Abstract: Process for the production of 2,5-dimethyl-1,5-hexadiene by heating isobutene with a 1,1,2-trihalo ethylene in the vapor phase in the presence of a free-radical generator. The free-radical generator is preferably a peroxide and the reaction temperature in the range 200.degree.-600.degree. C. The product may be readily isomerized to 2,5-dimethyl-2,4-hexadiene, which is useful as an insecticide intermediate.
    Type: Grant
    Filed: July 2, 1976
    Date of Patent: December 19, 1978
    Assignee: Imperial Chemical Industries Limited
    Inventors: Warren Hewertson, David Holland, David J. Milner
  • Production of aromatic polyesters of improved color
    Patent number: 4082724
    Abstract: A polyethylene terephthalate composition comprising highly polymeric polyethylene terephthalate and in an amount sufficient to prevent color degradation of said polyethylene terephthalate (1) a trihalide or tri (pseudohalide) of antimony, and (2) an organic oxo compound of phosphorus.
    Type: Grant
    Filed: May 24, 1974
    Date of Patent: April 4, 1978
    Assignee: Imperial Chemical Industries Limited
    Inventor: Warren Hewertson