VORRICHTUNG UND VERFAHREN ZUR HERSTELLUNG EINES MEHRSCHICHTIGEN GEGENSTANDES, WIE Z.B. EINES VORFORMLINGS, BEISPIELSWEISE ZUR HERSTELLUNG EINES BLASGEFORMTEN BEHAELTERS.

摘要

A multi-layer laminate structure from which containers are injection blow moldable, includes a layer of scrap (111) composed of the other thermoplastic resins used in making the laminate structure, which comprises outer and inner polyolefin layers (103, 105) an intermediate oxygen barrier layer (107), preferably ethylene-vinyl alcohol copolymer, and adhesive layers (109, 113) bonding the barrier layer to the inner layer (105) and the scrap layer (111) which is interiorly of the outer polyolefin layer. Apparatus (1) for producing parisons having such a structure has a sequence of extruder elements (3, 4, 5) which discharge polymeric materials in turn into a common duct (42) to form a laminate composed of a plurality of thin polymeric layers, said duct conveying the laminate to a principal delivery channel (40) for joining with a relatively thick polymeric layer flowing in the principal delivery channel (40) from another extruder element (7) upstream of the said elements (3, 4, 5); the resulting structure thereafter issues as a parison from a nozzle (23) of the apparatus (1).