Preparation of pigments
US6512115B2 · kind B2 · utility
1Cited by
9References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 6, 2001 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Mar 6, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B19/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a process for preparing triphendioxazine compounds by cyclizing the intermediates (IV) in the presence of manganese oxide and sulfuric acid to form compounds of the general formula (I) a process for condensing compounds of the general formula (II) with compounds of the general formula (III) to form the chlorine-free intermediates (IV) and also compounds of the general formula (IV).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.