Apparatus for making a wood-plastic profile
US6527532B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1998 |
| Grant date | Mar 4, 2003 |
| Priority date | — |
| Expiry date | Dec 21, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/94
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a method for making a dimensionally stable wood-thermoplastic composite material composed of a wood component and a thermoplastic component comprising the steps of forming a wood-thermoplastic mass at a temperature above the melting temperature of the thermoplastic component. The mass is then passed through a converging die to form a shaped extrudate profile having a cross sectional shape wherein at least a part of the converging die is maintained at a substantially higher temperature than that of the mass. The profile is then fed through a low friction thermally insulating land section, the land section having the substantially the same cross sectional shape as the exit end of the converging die. The profile is then quenched in a non-oxidizing environment to form a substantially dimensionally stable outer shell around the profile, the shell having a temperature below the melting temperature of the thermoplastic component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.