Process for polyesters with improved properties
US6048957A · kind A · utility
25Cited by
9References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1998 |
| Grant date | Apr 11, 2000 |
| Priority date | — |
| Expiry date | Apr 24, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29B2009/165
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a process for producing polyesters displaying exceptionally low acetaldehyde concentrations and good clarity comprising the steps of: PA1 polycondensing in the melt phase, a polyester monomer/oligomer mixture under conditions sufficient to form a precursor having in intrinsic viscosity less than 75% of a possible maximum intrinsic viscosity; and PA1 solid stating said precursor under conditions sufficient to increase said intrinsic viscosity at least about 0.05 dl/g.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.