| 摘要 |
<p>PURPOSE:To manufacture a bottle stretched sufficiently and having a firm base, by heating the front end of a stretch rod beforehand, by stretching a bottomed parison in the axial direction by the stretch rod thus heated, and by subjecting the stretched parison to blow molding. CONSTITUTION:A bottomed parison 1 is heated and then set in a mold 3, with the top portion of the parison 1 held by a chuck 2. A stretch rod 4 moving vertically through the center of the chuck 2 pushes up the base of the parison 1 to stretch the parison in the axial direction, while compressed air or the like is blown in through holes 41 of the stretch rod to stretch the parison in the circumferential direction and to subject the same to blow molding. The front end of the stretch rod 4 is heated beforehand to a temperature higher than the glass transition temperature of the plastic constituting the parison and lower than the melting point thereof.</p> |
