Patent · US Expired

Method of three layer injection molding with sequential and simultaneous coinjection

US6099780A · kind A · utility

42Cited by
7References
8Claims
0Family size

Inventor

Key dates

Filing dateDec 3, 1998
Grant dateAug 8, 2000
Priority date
Expiry dateDec 3, 2018

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29K2105/253
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method of multi-cavity valve gated three layer injection molding to form containers or preforms having a middle layer of a barrier material between inner and outer layers of a PET type material. The barrier material is injected through an annular channel in each heated nozzle simultaneously with the PET type material being injected through a central melt bore in each valve pin. This reduces cycle time and produces a thicker inner layer of PET.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.