METHOD FOR THE PRODUCTION OF A MULTI-LAYER PREFORM AND NOZZLE THEREFOR

摘要

A melt feed device for an injection molding apparatus having at least one nozzle element connected both to a first hot runner and a second hot runner for feeding both the first melt and the second melt into an injection molding mold. The nozzle has three substantially concentrically arranged feed passages, wherein the innermost and the outermost feed passage are in communication with the first hot runner and the central feed passage is in communication with the second hot runner. A closure element is provided that can be reciprocated between a first position in which the closure element closes all feed passages, a second position in which the closure element opens the outermost feed passage but closes the other two feed passages and a third position in which the closure element opens all feed passages. The invention also includes process and molds using the device.