| 摘要 |
<p>PURPOSE: To prevent the heat creep phenomenon of a bottom part at a time of heating and sterilization by forming the bottom part of the molded body of a preform into a dome shape to form a secondary molded body and heating the bottom part and a part of the body part of the molded body by an infrared radiator to shrink the same and setting the bottom part to a size received in a semispherical plane to perform secondary blow molding. CONSTITUTION: The neck part of a preform is supported by a core mold 34 and a fluid is blown into the preform to form a secondary molded body 30. Next, the bottom part 38 and a part 39 of the body part of the secondary molded body 30 is heated by infrared heaters 42, 43 in a heat treatment process to obtain a tertiary molded body 40 wherein the bottom part 38 and a part 39 of the body part are shrunk. In this case, the bottom part 45 and a part 46 of the body part are set to a size wherein the trough bottom part of a final container is received in an imaginary semispherical plane 60 and formed into a shape relatively approaching the semispherical plane 60. Next, a fluid is blown into split molds 52 to perform secondary blow molding to form the bottom shape of the final container equipped with trough parts and foot parts by a bottom mold 5.</p> |
