This invention relates to a process for preparing pigment compositions by conditioning an organic pigment, at about 50 to about 200.degree. C., with (1) at least about 0.1% by weight, relative to the organic pigment, of one or more surfactants of formula (I) ##STR1## wherein R.sup.1 is a C.sub.8 -C.sub.30 aliphatic group optionally having one or more carbon atoms in the main chain replaced with --O--, --S--, --CONH--, --NHCO--, --CH.dbd.CH--, C.sub.5 -C.sub.7 cycloalkylene, phenylene, or --OSi(C.sub.1 -C.sub.4 alkyl).sub.2 -, R.sup.2 is hydrogen, C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.6 hydroxyalkyl, R.sup.3 is hydrogen, C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.6 hydroxyalkyl, or R.sup.2 and R.sup.3 together are C.sub.4 -C.sub.7 alkylene, and X is a direct bond, or X and R.sup.2 form a five- to seven-membered heterocyclic ring (and R.sup.3 can form a double bond in X), or X, R.sup.2, and R.sup.3 together with the N-oxide nitrogen atom represent a bicyclic heterocycle, and (2) about 1 to about 100 parts by weight, per part by weight of the organic pigment, of a liquid in which the organic pigment is substantially insoluble.

This invention relates to a process for preparing pigment compositions by conditioning an organic pigment, at about 50 to about 200.degree. C., with (1) at least about 0.1% by weight, relative to the organic pigment, of one or more surfactants of formula (I) and/or formula (II) ##STR1## and/or ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, X, Y, Z, and Z' are defined herein; and (2) about 1 to about 100 parts by weight, per part by weight of the organic pigment, of a liquid in which the organic pigment is substantially insoluble.

The use of sulfuric monoesters of the formulae (I) and (II) in which R.sup.1 is a straight-chain or branched alkyl group of 10 to 24 carbon atoms, R.sup.2 is a hydrogen atom or a C.sub.1 -C.sub.6 -alkyl group, M.sup.+ is a hydrogen ion, an alkali metal ion, 1/2 an alkaline earth metal ion, or an ammonium ion of the formula N.sup.+ R.sup.3 R.sup.4 R.sup.5 R.sup.6, where the substituents R.sup.3, R.sup.4, R.sup.5 and R.sup.6 independently of one another are each hydrogen atoms or C.sub.1 -C.sub.6 -alkyl groups, which alkyl groups can be substituted by 1 to 3 hydroxyl groups, and n is a number from 0 to 4; or of a mixture of at least two sulfuric monoesters of the formulae (I) and/or (II), for preparing surface-treated pigments from the classes of the quinacridones and dioxazines.

This invention relates to a process for preparing perylene pigment compositions by (a) reacting, at a temperature of less than about 25.degree. C., a mixture of (1) a perylene tetracarboxylic compound, (2) at least about 0.1% by weight, relative to the perylene tetracarboxylic compound, of a surfactant of formula (I) ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, X, Y, Z, and Z' are defined herein, (3) an equivalent excess, relative to the amount of the perylene tetracarboxylic compound, of ammonia or a primary amine R.sup.A --NH.sub.2, wherein R.sup.A is defined herein, and (4) optionally, a solvent, to form a perylene intermediate; (b) heating the perylene intermediate at a temperature of about 50.degree. C. to about 250.degree. C., optionally in the presence of certain non-pigmentary cyclic anhydrides or imides and/or solvents; and (c) collecting the perylene pigment composition.

Linear unsubstituted and substituted quinacridone pigments and quinacridone mixed-crystal pigments are obtained by cyclizing dianilinoterephthalic acid with polyphosphoric acid and then hydrolyzing the ring closure mixture, said mixture being metered into an amount of water or orthophosphoric acid which is such that the final orthophosphoric acid concentration is greater than or equal to 50% by weight in the hedrolysis mixture.