| 摘要 |
A foamable plastic material is introduced to an extruder to produce a tubular parison of the material that is subsequently clamped between mold halves moving both axially and radially inwardly to form cavities for open mounted containers. Cavities for two containers are provided with each set of mold haves clamped together around the parison at the middle of the mold set to provide individual container cavities extending on either side of the clamped portion, said individual cavities terminating in the mouth portion of the container cavity which is joined in a mouth to mouth relationship with an individual container cavity of the next set of mold halves. A portion of the molten plastic material can be removed from the parison extruder at a point upstream from the point of introduction of a foaming agent and routed to the extrusion head where it is coextruded with the material containing foaming agent thus resulting in a coextruded parison having an outer layer of plastic material that contains no foaming agent and an inner layer of the same plastic material that contains a foaming agent. The resulting product is one where the outer layer provides a smooth and glossy surface finish of unfoamed plastic material to the container comprised mainly of foamed plastic material.
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