Patents by Inventor Tutomu Isaka

Tutomu Isaka 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).

  • Stretching of polyethylene terephthalate films
    Patent number: 4237088
    Abstract: Biaxially oriented thermoplastic films, for example polyethylene terephthalate films, are further stretched in one direction in a stretching zone having a distance in the direction of stretching which is greater than the breadth of said film. As a result, stretched films having a uniform thickness in the breadthwise direction are obtained in a high yield rate.
    Type: Grant
    Filed: October 12, 1978
    Date of Patent: December 2, 1980
    Assignee: Toyobo Co., Ltd.
    Inventors: Shohei Yoshimura, Tutomu Isaka
  • Method of stretching polypropylene films
    Patent number: 4134957
    Abstract: Biaxially oriented thermoplastic films, for example polypropylene films, are further stretched in one direction in a stretching zone having a distance in the direction of stretching which is greater than the breadth of said film. As a result, stretched films having a uniform thickness in the breadthwise direction are obtained in a high yield rate.
    Type: Grant
    Filed: February 16, 1978
    Date of Patent: January 16, 1979
    Assignee: Toyobo Co., Ltd.
    Inventors: Shohei Yoshimura, Tutomu Isaka