Abstract: Finely divided 1,4-diketopyrrolo[3,4-c]pyrroles of the formula ##STR1## where A and B are each independently of the other a radical of the formula ##STR2## wherein at least 84% by weight of the particles have a Stokes equivalent diameter of .ltoreq.0.25 .mu.m, and mixtures thereof.The substituents R.sub.1 and R.sub.2 are defined in claim 1.These pigments are notable for a very pure hue and outstanding transparency.

Abstract: Mixed crystals of at least two different compounds of formula ##STR1## wherein A and B are each independently of the other a cation of formula ##EQU1## or N.sup.+ H(R.sub.1)(R.sub.2)(R.sub.3) M is a mono-, di- or trivalent metal cation, n is 1, 2 or 3, R.sub.1, R.sub.2 and R.sub.3 are each independently of one another hydrogen, C.sub.1 -C.sub.22 alkyl, C.sub.7 -C.sub.24 aralkyl, C.sub.5 -C.sub.6 cycloalkyl or C.sub.6 -C.sub.18 aryl, m is 0 or 1, and R is hydrogen, C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, in which compounds of formula I that form the mixed crystals the cations A and B constitute a composite structure ##EQU2## wherein x is a value from 0.2 to 0.8, and the X-ray diffraction pattern of said mixed crystals differs from that of the corresponding compounds in which x is 1 or 0.These mixed crystals can be used as pigments for colouring organic material of high molecular weight and have exceptional properties, especially dispersibility, heat- and lightfastness.

Abstract: Dyes of formula ##STR1## wherein D is the radical of a diazo component of the benzene or naphthalene series or of the heterocyclic series, R.sub.1 is hydrogen or C.sub.1 -C.sub.4 alkyl and R.sub.2 is phenyl or substituted phenyl, give dyeings of good fastness properties on nitrogen-containing or hydroxyl group containing fibre materials.