Process for producing a shaped article by injection moulding
US4459257A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1983 |
| Grant date | Jul 10, 1984 |
| Priority date | — |
| Expiry date | Jun 29, 2003 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2011/0083
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The process for producing a shaped article comprising a polythene terephthalate (PETP) core containing from 0 to 50% of mineral fillers and a covering layer of a second thermoplastics material having a softening point below that of the PETP. The second material and the PETP are injected one after the other into a mould which is maintained at a temperature below the crystallization point of the PETP having regard to its fillers. The second material injected in the first phase acts as a thermal buffer slowing down temperature equalization between the PETP injected in the second injection phase and the mould, thus ensuring the required properties in the PETP core.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.