METHOD OF PREPARING A MOLDED ARTICLE

摘要

A method of forming a shaped thermoplastic sheet includes providing a mold apparatus that includes a first mold portion having a contoured and perforated interior mold surface, and a perimeter edge. At least one sheet retainer attaches to the upper surface of a frame the surrounds at least a portion of the first mold portion perimeter edge. Each sheet retainer includes a clamp portion that is positionable relative to the perimeter edge of the first mold portion. With a first portion of a heated thermoplastic sheet retained within the clamp portion a step of the method includes independently, reversibly and laterally moving each sheet retainer, towards and/or away from the perimeter edge of the first mold portion. Sheet retainer positioning allows localized control over the contacting of the interior mold surface and heated thermoplastic sheet thickness which controls the thickness of vanous portions of the final molded article