Yoshino Kogyosho Co., Ltd.

Yuich Okuyama

Masahiro Sugai

Yoshihiro Fuse

A biaxially stretched, blow molded bottle made of a resin comprising at least one of polyethylene terephthalate and a copolymerized polyester comprising ethylene terephthalate. The bottle neck is formed, just as the bottle body is formed, by expanding a body of a preform in a shape of a test tube in a stretching step of the molding process. The bottle neck has an average thickness in a range of 0.6 to 1.8 mm, and at the bottle neck, the resin is partially crystallized and is in an oriented crystallized state. A ratio of an absolute value of crystallization enthalpy, &#x394;Hc, to melting enthalpy, &#x394;Hm (|&#x394;Hc|/&#x394;Hm) of the bottle neck is a value less than 0.1, and a rate of dimensional change in the outer diameter of the bottle neck is 0.2% or less.

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Isehara, Japan

Yuich Okuyama