Patent · US Expired

Moulding process and article produced by the process

US6120714A · kind A · utility

20Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1997
Grant dateSep 19, 2000
Priority date
Expiry dateOct 31, 2017

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2035/0811
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A process for forming a molded article having a multilayer structure which comprises successively injecting melts of at least two materials into the cavity portion of a mold, solidifying a part thereof in the cavity portion to form the multilayer structure, characterized in that as a first step, one of the molten materials is injected into the cavity portion and the portion of the injected molten material contacting with the mold surface is solidified to a predetermined thickness to form a skin layer; as the second step, the next molten materials is fed into the cavity, the unsolidified portion of the molten material previously fed is pushed out of the cavity and a part of the thus fed molten material is cooled and solidified from the surface of the mold to form the next layer; and the procedure of the second step is successively repeated using the remainder of the molten materials alternately, and the molded article produced by the above molding process.

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