Abstract: A blow mold high-pressure switching step in a blow molding process of an injection stretch blow molding machine is arranged at the first half portion of the blow molding process, to shorten the injection molding process and improve the moldability. The blow mold high-pressure switching step 61B3 of increasing a mold clamping force for blow molds which have been closed in a blow molding process 61B is configured to be performed at a timing within a time from the start of the upper/lower mold opening step 62A1 for opening upper and lower molds in the injection molding process 62A to release a preform 3P to the completion of the injection mold high-pressure switching step 62A3 for increasing the mold clamping force for the closed injection molding mold.

Abstract: When a hollow molded body using a preform to be molded with a thin bottom portion is produced while taking advantage of the roughening of the outer surface of an injection core mold, transferred roughening marks are prevented from appearing on the bottom portion of hollow molded bodies, so that the hollow molded body with an aesthetic bottom portion is obtained. An injection core mold (12) has an outer surface of its tip portion corresponding to a preform bottom portion (10) and a lower end portion (14a) of a preform body portion (14). The outer surface corresponding to the preform bottom portion (10) and the lower end portion (14a) of the preform body portion (14) is a mirror-finished surface (20), and the outer surface of the injection core mold for forming the preform other than the mirror-finished surface is a roughened surface (15).

Abstract: An object is to provide an injection stretch blow molding machine and a method for molding a polyethylene container capable of molding a favorable hollow container even if its preform is released from an injection mold early. The injection stretch blow molding machine and the method for molding a polyethylene container molds a preform by injecting and filling a molten polyethylene resin into an injection mold, which includes a cavity mold and a core mold both cooled to a temperature range of 5° C. to 25° C., transfers the molded preform to a blow molding mold, and molds a hollow container by blowing the preform within a time range of ±2 sec from a point in time when a temperature of the preform reaches a first minimum point after a point in time when the injection mold completes being opened.

Abstract: Fixation of a container shape of a hollow molded body is not completed during a blow molding process but is completed during an ejection process of an ejection section, thereby shortening an operation time in a stretch blow molding section, and improving the production efficiency of hollow molded bodies by shortening the time required for the blow molding process during a molding cycle. Cooling air is blown into the inside of the hollow molded body disposed in the ejection section in the ejection process C during the blow molding process B in the next molding cycle to cool the hollow molded body disposed in the ejection section to solidify the container shape.

Abstract: A plastic bottle is provided with a mouth, a main unit, for example, a flexible, cylindrical main unit, connecting the interior of the bottle with the mouth, a base structured to close the bottom portion of the main unit and have a greater rigidity compared to the main unit. The main unit includes a lower body section extending upward from the base, a central body section extending upward from the lower body section, and a crease between the lower and central body sections. The central body section can be configured to deform into a substantially flat shape through the action of external force F so as to bend outward.