| 摘要 |
A method is disclosed for blow molding polyethylene terephthalate preforms, such as injection molded parisons, to achieve exterior surface indentations on blown containers without using profiled mold cavity walls. In the method, a profile is molded or otherwise formed in the exterior wall of the preform, defining a preform wall portion having sections of different thicknesses. Then, the preform is blow molded under conditions so that the polyethylene terephthalate material strain hardens in order to cause the different wall thicknesses to expand and stretch proportionately. As a result, the blown containers formed by this method include a surface contour which is essentially proportionately shaped to the surface profile formed on the pre-existing preforms.
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