摘要:
Methods and systems for co-injection molding multilayer articles having one or more molded apertures disposed between a gate region and a peripheral region of the article are disclosed. The articles include an interior layer disposed between an inner layer and an outer layer. An article has interior layer coverage over at least 98% of a perimeter of a cross-section of the article downstream of the one or more molded apertures. A method includes modifying fluid flowing past an aperture-forming region of a mold cavity to compensate for the drag of the aperture-forming region on the velocity of the fluid flowing proximal to the aperture-forming region.
摘要:
A mold for molding an injection molded article comprises a mold cavity with a non-symmetrical portion. At least one flow leader in the non-symmetrical portion of the cavity produces a symmetrical flow boundary in a multilayer flow downstream of the non-symmetrical portion of the mold cavity. The at least one flow leader may be a variable thickness flow leader or may alternatively be a plurality of flow leaders having a flow path length that differs from the flow path length of an adjacent flow leader by no more than about 15%. The multilayer flow comprising an inner layer, an outer layer, and an interior layer. Co-injection molding apparatus and methods that may use the foregoing mold are disclosed. Similarly, co-injection molded articles and containers that may result from the foregoing mold, apparatus, and methods are disclosed.