Patents by Inventor Toru Koma

Toru Koma 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: 5607621
    Abstract: Disclosed are a phosphorescent synthetic resin material capable of absorbing and accumulating light therein in the light and phosphorescing in the dark, a method for the production of the material, and a formed article or molded article made of the phosphorescent synthetic resin material. The phosphorescent synthetic resin material having a phosphorescent pigment, SrAl.sub.2 O.sub.4, uniformly dispersed in the synthetic resin is obtained by mixing the synthetic resin with the phosphorescent pigment and an activator and kneading the resultant mixture at a temperature 10 to 20.degree. C. higher than the melting point of the synthetic resin. In a preferred embodiment, the resultant compound is extruded at a temperature 10.degree. to 20.degree. C. higher than the melting point of the synthetic resin under an extrusion pressure in the range of 50 to 130 kg/cm.sup.2 and the extruded strands are chopped to produce pellets.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: March 4, 1997
    Assignee: YKK Corporation
    Inventors: Kiyomitsu Ishihara, Takayuki Yonetani, Yoshiharu Yamaguchi, Toru Koma