Blow molding method, blow mold, and blow-molded container

A method including a blow molding method for two-step blow molding into a final molded article having a temporary part that is cut off for obtaining an end product, the method comprising the steps of:

• a primary blow molding step that blow-molds a preform into an intermediate molded article in a primary blow mold, the primary blow mold including a primary temperature control section, and the intermediate molded article having the temporary part;
• a shrinkage step that discharges blow air from the intermediate molded article to shrink the intermediate molded article in the primary blow mold;
• a secondary blow molding step that blow-molds the intermediate molded article into the final molded article in a secondary blow mold, the secondary blow mold including a secondary temperature control section, and
• cutting off the temporary part from the final molded article,
• wherein the primary blow mold includes a first primary temperature control section, a second primary temperature control section and a third primary temperature control section that are defined by dividing the primary temperature control section in a vertical stretch direction,
• wherein the primary blow molding step includes:
• cooling a first intermediate molding region of the intermediate molded article that follows a neck thereof and corresponds to the temporary part of the final molded article using the first primary temperature control section,
• controlling a temperature of a second intermediate molding region that corresponds to a bottomed body of the end product to a temperature higher than a temperature set for the first primary temperature control section using the second primary temperature control section, and
• controlling a temperature of a third intermediate molding region that corresponds to a neck of the end product and is situated between the first intermediate molding region and the second intermediate molding region to a temperature between a temperature set to the first primary temperature control section and a temperature set to the second primary temperature control section using the third primary temperature control section, and
• wherein the shrinkage step shrinks a second intermediate molding region of the intermediate molded article, the temperature of the second intermediate molding region having been controlled by the second primary temperature control section.