Process for preparation of yellow shade modification of gamma quinacridone
US4760144A · kind A · utility
13Cited by
8References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1986 |
| Grant date | Jul 26, 1988 |
| Priority date | — |
| Expiry date | Nov 13, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B67/0027
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Process for preparing yellow shade modification of gamma quinacridone whereby the .gamma..sub.II form is converted to the .gamma..sub.I form (1) by milling in an alcohol and in the presence of a base or (2) by premilling the .gamma..sub.II form to the .gamma..sub.I form and then refluxing or milling the resulting .gamma..sub.I form in an alcohol in the presence of a base, the resulting product being a highly crystalline, bright, yellow shade, ready dispersable .gamma..sub.I quinacridone pigment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.