PRODUCTION OF MULTILAYERED PLASTIC CONTAINER

摘要

PURPOSE:To obtain a multilayered plastic container excellent in moldability and wall thickness distribution by cooling the surface temp. of at least one of polyolefin layers forming both surface layers of a multilayered sheet to specific temp. and subsequently heating both surface layers to specific temp. to mold the sheet. CONSTITUTION:A multilayered sheet 2 consisting of both surface polyolefin layers, an intermediate layer composed of an oxygen barrier resin with oxygen permeability of 300cc.25mum/m.24hr.atm (25 deg.C, 65%RH) and an interposing layer composed of a modified polyolefinic adhesive resin is formed by co- extrusion and the surface of the sheet 2 on the side being in contact with the surfaces of hot water cooling rolls 3, 4 long is cooled to the m.p. of polyolefin or lower. Subsequently, the surface temp. of both surface layers is heated to temp. higher than the temp. of the intermediate barrier layer and higher than the m.p. of polyolefin forming the surface layers by 1-60 deg.C. Next, the sheet is rapidly molded into a plastic container in-line by a thermal forming apparatus 9.