Process for preparing low color polyarylates
US4959449A · kind A · utility
5Cited by
2References
40Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 25, 1989 |
| Grant date | Sep 25, 1990 |
| Priority date | — |
| Expiry date | May 25, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/83
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polyarylates formed by reacting the diester of a dihydric phenol such as bisphenol-A and at least one aromatic dicarboxylic acid in the presence of an esterification catalyst is provided with improved color by the addition of cobalt during polymerization. The amount of cobalt can be reduced and an additional amount of an ultramarine blue pigment can be added to the reaction mixture to maintain the color improvement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.