Process for production of multi-layer pipes for draw-forming
US4649004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 1984 |
| Grant date | Mar 10, 1987 |
| Priority date | — |
| Expiry date | Dec 26, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31797
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process for the production of a multi-layer pipe to be used for formation of a bottle by drawblow-forming, comprising forming by co-extrusion a pipe having inner and outer layers of a polyester composed mainly of ethylene terephthalate units and an intermediate layer of an oxygen-barrier resin interposed between the inner and outer layers. An adhesive resin layer is preferable interposed between every two adjacent layers. The co-extruded multi-layer pipe is sized in the molten state so that the diameter of the pipe is uniform. The process continues by cooling the outer portion of the molten multi-layer pipe by contact with water and simultaneously introducing an inert gas or an inert gas containing a water mist into the interior of the pipe to thereby cool the inner portion of the pipe and prevent oxidation in the pipe. A multi-layer pipe prepared according to this process is excellent in the transparency and the draw-formability into a multi-layer drawn bottle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.