Patent · US Expired

Process for injection foaming, and machine and composition therefore

US6773640B2 · kind B2 · utility

10Cited by
8References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 21, 2001
Grant dateAug 10, 2004
Priority date
Expiry dateJun 2, 2022

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29D35/148
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A process for injection-foaming a thermoplastic resin by using an injection molding machine with a two-stage-compression screw, injecting a physical foaming agent into the cylinder of the machine at a pressure lower than the storage pressure of the physical foaming agent, mixing it with a melted resin and expanding the volume of the cavity of the mold at the time of injection, and an injection molding machine and resin composition suitable therefore.

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