Patents by Inventor Eric Albert Warwicker

Eric Albert Warwicker 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).

  • Water vapor permeable microporous sheet materials and their method of manufacture
    Patent number: 4090010
    Abstract: There is disclosed a process in which both non-solvent e.g., water and filler particles e.g., microscopic sodium chloride are added in certain proportions to a polymer solution e.g., polyurethane in dimethylformamide preferably at elevated temperature and coagulated by immersion in non-solvent. This results in a more rapid coagulation time than when solvent or filler alone are used and also results in a microporous product of improved properties and novel pore structure.
    Type: Grant
    Filed: June 11, 1973
    Date of Patent: May 16, 1978
    Assignee: Porvair Limited
    Inventors: Eric Albert Warwicker, David Price
  • Method of making water vapor permeable polymer sheet material
    Patent number: 4028451
    Abstract: Coagulation apparatus for producing thick microporous polyurethane sheet material by passing a layer of polymer solvent composition beneath a close spaced plate with liquid non-solvent fed to the gap between the plate and the surface to produce controlled initiation of the coagulation.
    Type: Grant
    Filed: February 5, 1975
    Date of Patent: June 7, 1977
    Assignee: Porvair Limited
    Inventor: Eric Albert Warwicker