Food quality polyester recycling
US5876644A · kind A · utility
46Cited by
19References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1996 |
| Grant date | Mar 2, 1999 |
| Priority date | — |
| Expiry date | Aug 27, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1352
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of recycling post-consumer polyester to obtain recycled polyester of sufficiently high purity to meet food packaging requirements is disclosed. The method includes cleaning comminuted pieces of post-consumer polyester to remove surface contaminants; melting the surface-cleaned post-consumer polyester pieces; extruding the post-consumer melt; blending the melt of post-consumer polyester with a melt of virgin polyester prepolymer; solidifying and pelletizing the blended melt while the virgin polyester prepolymer remains as prepolymer; and polymerizing the solid blended pellets in the solid state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.