Device and method for treating plastic material
US6716959B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 2001 |
| Grant date | Apr 6, 2004 |
| Priority date | — |
| Expiry date | Jul 20, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/10
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a method for treating plastic material, especially polyethylene terephthalate, wherein the relatively low temperature material is initially crystallized by heating before subjecting said material to heating or condensation in the solid phase. The material is then exposed to a hot treatment gas for at least 10 minutes in at least two chambers (2) of an apparatus and crystallized at a temperature above 135° C., e.g. 140-180° C. The is subsequently heated in a preheating chamber (3) having at least one to eight stages at a temperature of at least 185° C., preferably at least 200° C. and more preferably around 220° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.