Abstract: A process for the preparation of 2,4-dimethyl-3,5-bisalkoxycarbonylpyrrole is described, in which an acetoacetic alkyl ester is nitrosated to give the 2-nitrosoacetoacetic alkyl ester, the nitroso compound is reduced using hydrogen in the presence of a noble metal catalyst to give the amine, and the resulting amino compound is condensed without isolation in the presence of the corresponding non-nitrosated acetoacetic alkyl ester to give the 2,4-dimethyl-3,5-bisalkoxycarbonylpyrrole. The process makes it possible to work under conditions which are milder than in the prior art and to avoid the formation of by-products.

Abstract: A process for the preparation of 2,4-dimethylpyrrole is described in which a 2,4-dimethyl-3,5-bisalkoxycarbonylpyrrole is refluxed with from 10 to 30% strength aqueous alkali metal hydroxide solution until the solid has passed into solution, the reaction mixture is neutralized with acid and the mixture is refluxed further until decarboxylation is complete. The process makes it possible to work under significantly milder, less aggressive conditions than are known from the prior art.

Abstract: Dihydroquinacridones, quinacridones and quinacridonequinones are prepared by cyclizing 2,5-dianilino-3,6-dihydroterephthalic acid derivatives or 2,5-dianilinoterephthalic acid derivatives in the liquid or solid state or in solution, in each case in finely divided form, or in the gas phase, in the presence or absence of an oxidizing agent.

Abstract: Isoindoline pigments are conditioned by means of a heat treatment of the pigment in a mixture of water and benzenemonocarboxylic and/or benzenedicarboxylic acids.Well crystallized, very weatherfast pigmentary forms which give colorations possessing improved purity of shade are obtained.

Abstract: Isoindoline colorants of the formula ##STR1## where the radicals R independently of one another are each methyl or ethyl, give neutral yellow colorations when incorporated into surface coatings. The colorations do not darken on weathering and, compared with prior art pigments, exhibit improved gloss stability on weathering.

Abstract: Isoindoline dyes of the general formula ##STR1## where R.sup.1 is hydrogen, C.sub.1 -C.sub.4 -alkyl or benzyl and R.sup.2 and R.sup.3 independently of one another are each hydrogen, methyl, ethyl, methoxy, ethoxy, chlorine, bromine, fluorine, trifluoromethyl, methoxycarbonyl, ethoxycarbonyl or nitro, give pure brilliant deep yellow colorations with good lightfastness in surface coatings, printing inks and plastics.

Abstract: Compounds of the general formula I ##STR1## where R is hydrogen or C.sub.1 -C.sub.6 -alkyl and X is chlorine or bromine, with the proviso that X is only bromine when R is H, possess pigment properties and are distinguished by high color strength, brilliance and very good fastness properties.

Abstract: A novel modified diarylide pigment contains (a) a pigment which is composed of a tetrazotized benzidine, coupled to an acetoacetarylide and/or a 1-phenyl-3-methylpyrazole-5-one, and (b) a water-soluble component obtained from a symmetric or asymmetric coupling product of a tetrazotized 4,4'-diamino-2,2'-stilbenedisulfonic acid and an acetoacetarylide and/or a 1-phenyl-3-methyl-5-pyrazolone. The novel pigments possess very good color strength, very good gloss characteristics and very good transparency, and exhibit improved printing characteristics, particularly in offset printing inks.

Abstract: Isoindoline dyes of the formula ##STR1## where X is a radical of the formula ##STR2## and R is hydrogen, alkyl, benzyl, phenyl, napth-1-yl or a 5-membered or 6-membered unsaturated heterocyclic radical which may or may not be fused to a benzene ring, and the rings A, the phenyl ring, the naphthyl ring and the heterocyclic radical in R are unsubstituted or substituted by non-solubilizing groups, color finishes, printing inks and plastics in deep red or brown hues which are very lightfast and fast to migration.

Abstract: Isoindoline colorants of the formula ##STR1## where the two R's independently of one another are C.sub.1 -C.sub.4 -alkyl, or are benzyl, phenyl or 1-naphthyl, each of which may be unsubstituted or substituted by groups which do not confer solubility.The colorants give deep, yellow to orange, hues in plastics, surface coatings and printing inks. The colorations have very good lightfastness and fastness to weathering and to migration.

Abstract: Novel isoindoline colorants of the formula ##STR1## where R.sup.1 is phenyl or 1-naphthyl, which are unsubstituted or substituted by groups which do not confer solubility, R.sup.2 and R.sup.3, independently of one another, are C.sub.1 -C.sub.4 -alkyl or benzyl or R.sup.3 is hydrogen and R.sup.2 is C.sub.1 -C.sub.4 -alkyl or benzyl, or is phenyl or 1-naphthyl which are unsubstituted or substituted by groups which do not confer solubility, R.sup.1 and R.sup.2 being identical or different, and the use of these colorants.In surface coatings, printing inks and plastics, the products give brilliant yellow to red colorations, which exhibit very good lightfastness and fastness to weathering, and good fastness to overcoating.

Abstract: Isoindoline colorants of the formula ##STR1## where X is a radical of the formula ##STR2## R.sup.1 is hydrogen, C.sub.1 -C.sub.4 -alkyl, benzyl, phenyl, 1-naphthyl or a 5-membered or 6-membered, unsaturated heterocyclic radical which may or may not be benzo-fused, R.sup.2 and R.sup.3, independently of one another, are hydrogen, C.sub.1 -C.sub.4 -alkyl, benzyl, phenyl or 1-naphthyl, and the ring A and the phenyl, naphthyl and heterocyclic radicals in R.sup.1, R.sup.2 and R.sup.3 can be substituted by groups which do not confer solubility. The colorants give deep, strongly bluish red hues in surface coatings, printing inks and plastics. The colorations have good lightfastness and fastness to migration.

Abstract: Isoindoline colorants of the formula ##STR1## where R.sup.1 is the radical of a 5-membered or 6-membered heterocyclic unsaturated ring, which may or may not be fused to a benzo ring, X is ##STR2## R.sup.2 and R.sup.3 independently of one another are hydrogen, C.sub.1 -C.sub.4 -alkyl, benzyl, phenyl or 1-naphthyl, and R.sup.1, the phenyl and naphthyl radicals, and the ring A may or may not be substituted by groups which do not confer solubility.In surface coatings, printing inks and plastics the novel colorants give yellow to red or brown very deep colorations which have good lightfastness, and fastness to weathering and to overspraying.