BLOWMOLDING P.E.T.P. CONTAINER

摘要

A hollow blow-molded bottle-shaped container of a biaxially oriented polyethylene terephthalate which advantageously has a stepped portion (4) formed on the inner peripheral surface of a boundary between a neck portion (1) integrally formed with a shoulder portion (2) with a body portion (3) and the shoulder portion (2) and crystallized by a heat treatment before being biaxially oriented blow-molded from an injection-molded primary piece or parison (P), thereby abruptly reducing the thickness of the wall at the boundary from the neck portion (1) to the shoulder portion (2) to substantially equal to the thickness of the body portion (3). This bottle-shaped container is manufactured from a preformed piece or parison (P) injection-moulded in which a recess groove is formed on the peripheral surface of the shoulder portion forming portion (2a). Thus, the deterioration in the physical properties of the neck portion and shoulder portion of the bottle-shaped container can be eliminated.