PURPOSE: To realize a target fixed form and almost uniform thickness by a method wherein a preform, which is almost in the same form and thickness as those of a raised bottom part of a hollow vessel having the raised bottom is formed, which is pinched and pressed between the lower end face of a stretch rod having the form of the inside of the raised bottom part and a mold face of the raised bottom part of a flow mold and blow molding is performed.
CONSTITUTION: A bottomed and tubular preform 1 having a raised bottom 2 possessing almost the same form and thickness as those of a raised bottom part 12 of a hollow vessel 11 is formed, which is put into a blow mold 3 under a softened state and a form of the lower end face 8 of a stretch rod 6 is made into that of the inside of the raised bottom part 12 of the hollow vessel 11 which is going to mold. A mold face of a movable mold 3a is fitted in the undersurface of the raised bottom 2, which is placed between the stretch rod 6 and movable mold 3a vertically, the stretch rod 6 and movable mold 3a are displaced in the direction 7 and the preform 1 is stretched in the direction 7. Then a preform 1a is stuck close to the mold face of the blow mold 3, molded and taken out by sending air 104 into a preform 1a.
MATSUHASHI SETSU
TOKIWA DAIROKU
