Patents Assigned to Mitsui Petrochemical Co., Ltd.
  • Patent number: 5286187
    Abstract: A machine for molding a starting crystalline saturated polyester resin such as polyethylene terephthalate includes a device for first drying and then preheating the starting resin to a temperature above its melting point to lower the viscosity of the resin to such an extent that the resin is not substantially degraded in the compression section of the molding machine. A feed section is provided for quantitatively feeding the molten starting resin to the main body of the molding machine. Accordingly, the starting resin is molded into a desired shape in a molding machine under conditions such that the crystallization temperature of the resulting molded article is within 20.degree. C. of the crystallization temperature of the starting saturated crystalline polyester resin.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: February 15, 1994
    Assignee: Mitsui Petrochemical Co., Ltd.
    Inventors: Hiroji Niimi, Takashi Satake, Kunio Tomita