Patents by Inventor Katsutoshi Miyakawa

Katsutoshi Miyakawa 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).

  • Method of producing thermoplastic resin films and apparatus for producing the same
    Patent number: 6221301
    Abstract: Method and apparatus for producing thermoplastic resin film which allows a biaxially oriented polyester film to be formed at a high speed of 400 m/min or more. In the method, a molten thermoplastic resin film is brought into contact with a cooling medium, to be cooled and solidified, for producing a cast film. The method is characterized by keeping the surface temperature of the cooling medium in the region immediately before the melt reaching position at not lower than the glass transition temperature and not higher than the melting point of the thermoplastic resin. The apparatus is characterized by a cooling medium having a heater and a cooler to ensure that the surface temperature of the cooling medium in the region immediately before the melt reaching position is kept at the requisite temperature, and by a surface temperature of the cooling drum in the region immediately before the film leaving position being maintained lower than the glass transition temperature of the thermoplastic resin.
    Type: Grant
    Filed: March 9, 1999
    Date of Patent: April 24, 2001
    Assignee: Toray Industries, Inc.
    Inventors: Kenji Tsunashima, Masaharu Toyama, Katsutoshi Miyakawa, Shunichi Osada, Nobutsugu Chigira, Hiroshi Yoshimura
  • Polyester film reflector for a surface light source
    Patent number: 5672409
    Abstract: A reflector used in a surface light source comprising a white polyester film in which fine voids are formed and whose apparent specific gravity is in the range of 0.5 to 1.2. The reflectance of the polyester film can be increased by the fine voids. When the reflector having a high reflectance is used in a surface light source having a side light system, a bright scope of, for example, a liquid crystal display easy to see can be obtained.
    Type: Grant
    Filed: November 15, 1993
    Date of Patent: September 30, 1997
    Assignee: Toray Industries, Inc.
    Inventors: Katsutoshi Miyakawa, Kenji Tsunashima, Seizo Aoki
  • Thermoplastic resin film
    Patent number: 5654394
    Abstract: A thermoplastic resin film wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio "Pw1/PwT" of the sum of spectral intensities of wave-number components present in the wave-number range of 0.15 to 0.45 (1/m) (Pw1) to the sum of spectral intensities of the full wave-number range (PwT) determined when a wave form of the variation in thickness is subjected to analysis of Fourier transformation is not more than 0.20, and wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio "Pw2/PwT" of the sum of spectral intensities of wave-number components present in the wave-number range of 1.00 to 2.00 (1/m) (Pw2) to the sum of spectral intensities of the full wave-number range (PwT) is not more than 0.15. In such a film, the uniformity in thickness can remarkably improved, and snaking and wrinkles in post processing can be prevented.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: August 5, 1997
    Assignee: Toray Industries, Inc.
    Inventors: Katsutoshi Miyakawa, Katsuya Toyoda, Akiko Yamamoto, Kenji Tsunashima, Toshiya Ieki