Process for producing molded article made of synthetic resin
US6180042A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1996 |
| Grant date | Jan 30, 2001 |
| Priority date | — |
| Expiry date | Nov 7, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/3044
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In producing a molded article of a synthetic resin, the following steps are used: a step of injecting an outer layer forming material into a molding cavity through a gate in a mold; a step of injecting a core forming material to allow the core forming material to flow into the outer layer forming material existing in the gate and the cavity and to allow the outer layer and core forming materials to flow within the cavity, thereby advancing the formation of the first construction portion; a step of allowing a front portion of the core forming material in a flowing direction to break through a front portion of the outer layer forming material in the flowing direction to flow into said cavity, thereby advancing the formation of the second construction portion under advancement of the first construction portion; and a step of pushing both the materials existing within the gate into said cavity by the outer layer material, thereby completing the formation of the first and second construction portion. Thus, it is possible to mass-produce a molded article of a synthetic resin including the first construction portion having a sandwich structure including a core and an outer layer, and the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.