| 摘要 |
PURPOSE:To obtain a thermoplastic polyester container having a high mechanical, chemical, and thermal stability, a high transparency, excellent dimensional stability, and good appearance by a method in which a thermoplastic polyester is molded by a blow mold, biaxially stretched in the mold, heat-set by steam, and then cooled by air. CONSTITUTION:A stretching rod 3 is raised by an air cylinder 4, and a preform 2 of polyester is stretched axially. A valve 12 is opened, compressed air is blown into the preform 2 through an ar inlet path to stretch the preform 2 in the sideward direction in order to obtain a blow molded container 2'. The valve 12 is then closed, an exhaust valve 6 is opened, and steam is blown onto the inner surface of the container 2' from a jet nozzle 8 through the stretching rod 3 at the same time as the gas is exhausted for heat setting. As soon as the heat setting is finished, the steam is switched to compresed cooling air to press and cool the inner surface of the container 2' while discharging the gas to obtain an objective container. |
