Abstract: The invention provides a process for preparing N,N?-di(3?,5?-dimethylphenyl)perylene bis(dicarboximide), and other pigments having modified properties, by reaction of perylene-3,4,9,10-tetracarboxylic dianhydride with 3,5-dimethylaniline, or a mixture of 3,5-dimethyl aniline and at least one other primary amine, in the presence of a secondary amine or tertiary amine as catalyst, wherein the reaction occurs in an aqueous reaction medium and in the presence of added seed crystals of N,N?-di(3?,5?-dimethylphenyl) perylenebis(dicarboximide), such that the aqueous medium is present at the beginning of the reaction.

Abstract: The invention provides a process for preparing N,N?-di(3?,5?-dimethylphenyl) perylenebis(dicarboximide) by reaction of perylene-3,4,9,10-tetracarboxylic dianhydride with 3,5-dimethylaniline in the presence of a secondary or tertiary amine as catalyst, which comprises effecting the reaction in an aqueous reaction medium and in the presence of added seed crystals of N,N?-di(3?,5?-dimethylphenyl) perylenebis(dicarboximide).

Abstract: Chlorinated violanthrones or isoviolanthrones are prepared by reacting violanthrone or isoviolanthrone with chlorine in the presence of a diluent, using aliphatic carboxylic acids and/or aliphatic halo carboxylic acids as diluent for this purpose.

Abstract: Colorant mixtures for use in printing inks contain isoquinoline-azo pigments of the formula I ##STR1## where X is chlorine, bromine, C.sub.1 -C.sub.4 -alkoxy or nitro,n is 1, 2 or 3, and the ring A can be substituted, and an isoquinoline-azo dye of the formula II ##STR2## where Y is C.sub.6 -C.sub.20 -alkoxy which may be interrupted by one or more oxygen atoms, and the ring B can be substituted.

Abstract: Haloisatoic anhydrides are prepared by halogenating appropriately unsubstituted isatoic anhydrides with elemental chlorine or bromine in the presence of chlorosulfonic acid at from -10.degree. C. to +100.degree. C. using not less than 0.5 mole of halogen per mole of isatoic anhydride.

Abstract: Isoindoline metal complexes of the formula I ##STR1## wherein R.sup.1 and R.sup.2 are independently of each other H or C.sub.1 -C.sub.4 -alkyl, X.sup..crclbar. is one equivalent of a colorless anion and Me is Zn.sup.2+, Ni.sup.2+, Co.sup.2+ or Cu.sup.2+, are suitable for pigmenting surface coatings, plastics and printing inks.

Abstract: Quinophthalone dyes of the formula ##STR1## where X is O or NC--C--R, where R is cyano, unsubstituted or N-substituted carbamyl, carboalkoxy, quinazolonyl, quinoxalinonyl, benzimidazolyl or benzothiazolyl and the rings A, B, the quinoline system and/or the fused benzo systems may be substituted by insolubilizing groups, in surface finishes, printing inks and plastics, in particular in thermoplastics, gives bright hues having good fastness properties coupled with high thermostability.

Abstract: Tetrachloro-3-iminosisoindolin-1-one (I) or its alkali metal salt (Ia) is prepared by reacting tetrachloro-ortho-phthalodinitrile with lithium hydroxide, sodium hydroxide and/or potassium hydroxide in substantially anhydrous tert-butanol and, if desired, liberating (I) from (Ia) by means of a dilute acid.

Abstract: Compounds which, in one of the possible tautomeric forms, correspond to the general formula I ##STR1## where n is 1 or 2 and, if n is 1, R is unsubstituted or substituted aryl or heteroaryl or, if n is 2, R is a bridge member, and the rings A and B can be further substituted, are outstanding colorants for surface coatings, printing inks or plastics.

Abstract: A compound having the formula (I): ##STR1## wherein D is a radical of a heterocyclic or aromatic component selected from the group of aniline, anthraquinone, phthalimide or aminobenzene radicals, wherein the radical is unsubstituted or is substituted by fluorine, chlorine, bromine, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, trifluoromethyl, cyano, C.sub.1 -C.sub.4 -alkylsulfonyl, carboxylic acid ester groups, carbamyl, sulfamyl, 1,3,4- or 1,2,4-oxadiazolyl or acylamino groups; X is CO-- or --SO.sub.2 --; and R is an aliphatic, aromatic or heterocyclic radical selected from the group of C.sub.1 -C.sub.