Method of making preform and container with crystallized neck finish

摘要

A preform and container each having a crystallized neck finish and method of making the same, wherein the method involves introducing a first thermoplastic material into a first mold section to form a substantially crystallized neck portion of a preform, and introducing a second thermoplastic material into a second mold section to form a substantially amorphous body-forming portion of a preform. The first material may have a substantially higher crystallization rate than the second material, and/or the first mold section may be at a higher temperature than the second mold section. In one embodiment, an indexer carrying two core sets is movable between first and second cavity sets for sequentially molding the neck portions on the first core set in the first cavity set, and then transferring the cores and neck portions to the second cavity set for molding the body-forming portions. The method enables cost-effective manufacture of preforms with crystallized neck finishes and enables production of a thermal resistant finish within a close dimensional tolerance.