Patent · US Expired

Process for producing multi-layer molded product

US6231798A · kind A · utility

5Cited by
12References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 27, 1996
Grant dateMay 15, 2001
Priority date
Expiry dateSep 27, 2016

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C2045/1609
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

There is provided a process for producing a multi-layer molded product having a plurality of thermoplastic resin layers. This process provides for (i) a step of supplying first and second molten thermoplastic resins each through first and second resin supplying gates which are temperature-controllable independently of each other, to between female and male molds kept in an open state with a time difference being provided between supply starts of the first and second resins, and (ii) a step of closing the female and male molds after completion of supply of the first and second resins. The process enables production of high-quality multi-layer molded products having a plurality of resin layers with good repeatability under relatively low resin supply pressure and by single mold closing. Further, high-quality multi-layer molded products can readily be produced without restrictions on materials used.

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