PARTIALLY FOAMED, THERMOFORMED CONTAINER AND PRODUCTION METHOD THEREFOR

摘要

A foamed container obtained by thermoforming a laminate sheet having an at least three-layered structure including a foamed core layer and non-foamed external layers on both sides of, and adjacent to, the foamed core layer, wherein the foamed core layer comprises a thermoplastic resin, an inorganic filler and a foaming agent, and 99.9 to 50 wt % of the thermoplastic resin and 0.1 to 50 wt % of the inorganic filler are blended to form a foamed body having open cells. Projections are formed on only the outer surface of the container and an expansion ratio of recesses formed in the inner surface of the container is lower than that of the foamed core layer of the laminate sheet before forming. The present invention can provide not only a foamed container having a uniform wall thickness distribution and uniform foaming but also a partially foamed container having a non-uniform wall thickness distribution and non-uniform foaming, having partially highly foamed portions and having an excellent design feature. The partially foamed container of this invention is obtained by moving a gas inside the foaming layer at the time of forming of the container and foaming a part of the container. Therefore, the wall thickness of the container becomes small at portions other than the foamed portion, and the container gives a thin-wall impression as a whole. Though the container is not bulky and is heat-insulating, it has a high heat conductivity and can be refrigerated or boiled.