Oxidation process for preparing quinacridone pigments
US5286863A · kind A · utility
20Cited by
18References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1991 |
| Grant date | Feb 15, 1994 |
| Priority date | — |
| Expiry date | Dec 18, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B48/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process for preparing quinacridone pigments comprising oxidizing 6,13-dihydroquinacridone or derivatives thereof at elevated temperatures in the presence of a base, dimethyl sulfoxide medium and a quinone catalyst, drowning the resulting pigment solution to precipitate the quinacridone pigment and isolating the desired quinacridone product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.