Patents by Inventor David J. C. Espley

David J. C. Espley 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).

  • Heat-sealable antistatic polypropylene films
    Patent number: 4294882
    Abstract: An oriented heat-sealable antistatic polypropylene film is manufactured by applying to one or both surfaces of a base polypropylene film, preferably by co-extrusion, a layer of a heat-sealable olefinic polymer (for example, a predominantly linear random copolymer of ethylene with butene-1) containing between 0.2 and 10% by weight of an anionic hydrocarbyl (preferably long chain alkyl) sulphonate. A slip agent, for example oleamide, may also be incorporated in the base polypropylene film. The antistatic film has improved heat-sealing properties which permits it to be run successfully on packaging machinery at high speeds.
    Type: Grant
    Filed: August 23, 1979
    Date of Patent: October 13, 1981
    Assignee: British Cellophane Limited
    Inventors: William J. Andrews, David J. C. Espley, William J. M. Philpott
  • Heat-sealable antistatic polypropylene films
    Patent number: RE31269
    Abstract: An oriented heat-sealable antistatic polypropylene film is manufactured by applying to one or both surfaces of a base polypropylene film, preferably by co-extrusion, a layer of a heat-sealable olefinic polymer (for example, a predominantly linear random copolymer of ethylene with butene-1) containing between 0.2 and 10% by weight of an anionic hydrocarbyl (preferably long chain alkyl) sulphonate. A slip agent, for example oleamide, may also be incorporated in the base polypropylene film. The antistatic film has improved heat-sealing properties which permits it to be run successfully on packaging machinery at high speeds.
    Type: Grant
    Filed: May 11, 1982
    Date of Patent: June 7, 1983
    Assignee: British Cellophane Limited
    Inventors: William J. Andrews, David J. C. Espley, William J. M. Philpott