| abstract |
The invention relates to mixed crystals of 1,4-diketopyrrolo[3,4-c]pyrroles, consisting of 1 mol each of two different compounds of formulae <IMAGE> (I) <IMAGE> (II) as well as single-phase solid solutions of two different compounds of formulae I and II, wherein the diketopyrrolopyrrole having the smaller geometrical constitution is present in an amount of 53 to 70 mol %. A and B are as defined in claim 1. The novel mixed crystals as well as the novel solid solutions are admirably suited for pigmenting organic material of high molecular weight. |