PURPOSE: To produce a blow molded product whose interior is partitioned along an injection direction using a small-sized device without damaging the strength and beauty thereof.
CONSTITUTION: In a blow molding method, a hollow round parison 5a is injected from the gap between a columnar core 12a and the cylindrical die 13a surrounding the core 12a and held in a mold to inject air into the parison. Resin passage grooves 15a guiding the resin on the side surface of the core toward the center of the core are radially formed to the leading end in the parison injection direction of the core 12a and, when the hollow round parison 5a is injected from the gap between the core 12a and the die 13a surrounding the core 12a, partition walls 16a are formed in the hollow round parison 5a by the resin passed through the resin passage grooves 15a and air is blown in the parison 5a within the mold.
IWAWAKI AKIRA
UMEZAWA YOSHIMASA
ARAKI SATOSHI
SHIMIZU TAKASHI
