Preparation of mixed crystals and solid solutions of 1, 4-diketo-pyrrolpyrroles
US5693824A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 1996 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Sep 12, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B67/0039
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for the preparation of mixed crystals of 1,4-diketopyrrolo3,4-c!pyrroles, consisting of 1 mol each of two different compounds of formula ##STR1## by heating a corresponding mixture in solid form to the temperature range from 220.degree. to 380.degree. C. A and B are, for example, each a group of formula ##STR2## wherein R.sub.1 and R.sub.2 are each independently hydrogen, chloro, bromo, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylamino, phenyl or --CN, G is --O--, --NR.sub.7 --, --N.dbd.N-- or --SO.sub.2 --, R.sub.3 and R.sub.4 are hydrogen, and R.sub.7 is hydrogen, methyl or ethyl. The mixed crystals and solid solutions obtained are excellently suited for pigmenting high molecular weight material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.