Apparatus and method for multi-layer injection molding

Abstract

An injection molding apparatus and method for multi-layer molding of preforms and closures has a central melt channel, an annular melt channel radially spaced from the central melt channel, and an annular ring channel surrounding the central melt channel. The central melt channel has a first portion for flow of a first material, a second portion for flow of the first material and a second material, and a flow extension connecting the first portion and the second portion. The flow extension has a flow opening in communication with the annular ring channel for flow of the second material. The apparatus and method also include a cavity for receiving flow of the first material and the second material from the central melt channel, and for receiving flow of a third material from the annular melt channel. In addition, the apparatus and method include a first melt passage in communication with the annular melt channel, a second melt passage in communication with the annular ring channel, and a third melt passage in communication with the central channel.

Dependencies are inferred from the claim text.