Patents by Inventor David Leonard Boutle

David Leonard Boutle 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).

  • Polyurethane-polyanhydride subbing layer for photo sensitive elements
    Patent number: 4093458
    Abstract: Polymeric subbing compositions for polyester photobase, especially polyethylene terephthalate films, comprising, a mixture of a polyurethane resin with a homopolymer or copolymer or a mixture of a homopolymer and a copolymer of an unsaturated cyclic carboxylic acid anhydride, preferably maleic anhydride or itaconic anhydride, in which the mixture contains up to 75% by weight of the anhydride polymer.
    Type: Grant
    Filed: June 1, 1976
    Date of Patent: June 6, 1978
    Assignee: Imperial Chemical Industries Limited
    Inventors: Patrick Terence McGrail, Stephen Richard Smith, Frederick Robert Bannister, David Leonard Boutle
  • Shoe uppers
    Patent number: 3982335
    Abstract: A shoe upper having in place of the upper leather thereof a fleeceless water vapor permeable microporous sheet of elastomeric polyurethane material having a thickness of about 0.8 - 1.8 mm. and having an extension at break of at least 200%.
    Type: Grant
    Filed: October 12, 1971
    Date of Patent: September 28, 1976
    Assignee: Porvair Limited
    Inventors: Victor Ralph Cunningham, David Leonard Boutle
  • Artificial leather sheet material
    Patent number: 3968293
    Abstract: A water vapor permeable artificial leather material is disclosed which consists essentially of tough microporous elastomeric polymer material free from fibrous reinforcement having a thickness of at least 0.8 mm and a microporous appearance modifying surface layer or finish.
    Type: Grant
    Filed: October 11, 1973
    Date of Patent: July 6, 1976
    Assignee: Porvair Limited
    Inventors: Victor Ralph Cunningham, David Leonard Boutle