Patents by Inventor Andrew J. Apps

Andrew J. Apps 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: 4152384
    Abstract: This invention provides a method for producing porous elastomeric sheet material, wherein ungelled elastomer liquid material is admixed with hollow spherical filler particles and then spread to form a sheet, which is then dried and gelled. The dried and gelled sheet of filled elastomer is subjected to rigorous biaxial stretching, wherein the elastomeric material surrounding at least some of the particles is stretched and ultimately broken by the rigorous stretching, to form a porous sheet material.
    Type: Grant
    Filed: June 20, 1977
    Date of Patent: May 1, 1979
    Assignee: 4D Research and Development Company Limited
    Inventor: Andrew J. Apps