Hoechst Aktiengesellschaft

Adolf Kroh

Otto Fuchs

Erwin Dietz

Ernst Spietschka

Otmar Hafner

Hans-Tobias Macholdt

Wolfgang Rieper

Alexander Sieber

Manfred Urban

Wolfgang Teige

Gustav Kapaun

Albert Munkel

Frank Prokschy

Michael Maikowski

Robert Gutbrod

Andreas Sommer

Michael Kappert

Jurgen Hohn

A process for the preparation of 2,9-dimethylquinacridone pigments or mixed crystal pigments or mixtures of 2,9-dimethylquinacridone and quinacridones which in the two outer fused benzene rings can be substituted, characterized by the form of their crystalline particles having an average ratio of length to width of &lt;2:1 and an average particle size of &lt;0.4 .mu.m, by adding to the solution of 2,9-dimethylquinacridone before or during the finishing of the corresponding crude quinacridones of the quinacridones mentioned in water or solvent mixtures at temperatures from about 60.degree. to about 200.degree. C., in each case a compound of the general formula (I) ##STR1## in an amount of about 1 to 20% by weight, in which Q is a quinacridone radical which is unsubstituted or substituted, Y is an --NR.sup.4 R.sup.5 group or the radical of a five-, six- or seven-membered heterocycle which contains one to three hetero atoms and can be substituted, R and R' are hydrogen or alkyl, and R.sup.1 to R.sup.5 are hydrogen and/or alkyl or alkylene, and n is a number from 1 to 4, the pigments themselves thus prepared and their use for the pigmenting of natural or synthetic materials and of lacquer systems.

Modified 2,9-dimethylquinacridone pigments, process for their

Quinacridones having selectively adjusted triboelectric effects, which quinacridones contain about 0.05% to 100 percent by weight of triboelectrically active compounds of the general formula I

Quinacridones having selectively adjusted triboelectric effects

Addition compounds which are suitable as dispersants for solids in organic media are obtained from polyepoxides based on novolaks having 3 to 11 nuclei and a mixture of aliphatic, aromatic and/or heterocyclic amines.

Addition compounds, a process for the preparation, and their use, based

Pigments of the formula I ##STR1## where A is a five- or six-membered aromatic fused or unfused heterocycle which contains one to three hetero atoms from the series consisting of nitrogen and/or oxygen and/or sulfur and which is bonded to the methylene group via a carbon atom, R.sub.1 and R.sub.2 are each hydrogen, alkyl C.sub.1 -C.sub.4, alkylene C.sub.2 or aryl, and together R.sub.1 and R.sub.2 may also be an aliphatic or aromatic ring, R.sub.3 is hydrogen, alkyl C.sub.1 -C.sub.4 hydroxylkyl C.sub.1 -C.sub.3 or alkylene C.sub.2, P is the radical of a polycyclic pigment or a radical of a mix-crystal of polycyclic pigments, and n is a number from 0.0001 to 0.2, are useful for pigmenting high molecular weight materials in the form of plastic materials, melts, spinning solutions, surface coatings, paints, printing inks, baking finishes of the class of the alkyd melamine resin or acrylic melamine resin finishes, two-component coatings based on polyisocyanate-crosslinkable acrylic resins and printing inks based on nitrocellulose.

Pigments and use thereof

An improved magenta colorant for electrophotographic multicolor recording processes, comprising mix-crystals from 95 to 60 parts of a compound of the formula I below and 5 to 40 parts of a compound of the following formula II ##STR1## and use thereof for preparing toners or developers which are used for electrophotographic copying of subject copies and for printing electronically, optically and magnetically stored data.

Magenta colorant for electrophotographic recording processes

A process for preparing the high-hiding form of the .gamma.-crystal modification of unsubstituted linear transquinacridone having improved tinctorial strength and producing a coating of higher gloss, which comprises carrying out (a) the known cyclization of 2,5-diphenylaminoterephthalic acid in highly concentrated polyphosphoric acid or in acid polyphosphoric acid ester to the quinacridone and/or (b) the known hydrolysis of the quinacridone melt obtained in (a) and/or (c) the known aqueous alkali extraction of the quinacridone obtained in (b) and/or (d) the known finishing of the quinacridone obtained in (a) in the presence of 0.5 to 10 percent by weight, based on quinacridone, of surface-active agents.

Process for preparing high-hiding gamma-modification of unsubstituted

Powdered pigments with improved rheological properties, processes for

Addition products formed from polymeric diphenylmethane 4,4'-diisocyanates, amines, monoactive and diactive polymers are suitable for use as dispersants for solids in organic media.

Addition compounds and process for their preparation

The invention relates to a process for coloring water-insoluble thermoplastic plastics with dyestuffs of the formula ##STR1## The dyestuffs are added to the melt of the thermoplastic plastic or to its precursors.

Process for mass coloring thermoplastic plastics

Compositions of linear trans-quinacridones containing at least one component (I) selected from unsubstituted, chloro- and methyl-substituted quinacridone and at least one component (II) selected from bis-(carbamoyl)-quinacridones, the carbamoyl groups of which are unsubstituted, N-mono-alkyl substituted or N,N-dialkyl-substituted, are pigments useful for coloring plastics and especially lacquers. These compositions are preferably prepared by joint ring closure of the corresponding 2,5-dianilino-terephthalic acids or esters.

Quinacridone mixtures, process for their manufacture and their use as

Easily dispersible preparations of organic pigments are obtained by coating the pigment particles with essentially colorless aromatic compounds having a molecular structure being similar to that of the pigment and having an aliphatic chain of more than 5 carbon atoms. These preparations are stable to flocculation and useful for pigmenting hydrophilic and hydrophobic media.

Pigment preparations

Unsubstituted linear trans-quinacridone of the gamma-crystal modification is obtained by cyclization of 2,5-dianilino-terephthalic acid with the 2.5 to 4-fold quantity of polyphosphoric acid or of an acidic polyphosphoric acid methyl ester, followed by hydrolysis of the condensation product in water, intensive grinding of the aqueous crude quinacridone in the presence of an alcohol or ketone and heating of the resulting product to 80.degree. to 200.degree. C.

Process for the manufacture of the gamma-crystal modification of linear

Naphthalimide-4,5-dicarboxylic acids of the formula ##STR1## or the anhydrides thereof, wherein R is alkyl having 1 to 8 carbon atoms or hydroxyalkyl or alkoxyalkyl having each 1 to 6 carbon atoms in the alkyl or alkoxy portion, which are obtained by reacting an alkali metal salt of naphthalene-1,4,5,8-tetracarboxylic acid in an aqueous solution with amines of the formula

Naphthalimide-4,5-dicarboxylic acids

Novel naphthalimide-4,5-dicarboxylic acids of the general formula ##STR1## or the anhydrides thereof, wherein R.sub.1 is hydrogen, hydroxy, amino, alkyl having 1 to 8 carbon atoms, hydroxyalkyl, alkoxyalkyl, aminoalkyl, monoalkylaminoalkyl, hydroxyalkoxyalkyl, alkoxyalkoxyalkyl, carbalkoxyalkyl, carboxyalkyl or phenylalkyl having each 1 to 6, preferably 1 to 4 carbon atoms in the alkyl or alkoxy portion or phenyl substituted by 1 to 3 halogen atoms, amino, alkyl, alkoxy, acylamino, acyl having each 1 to 4 carbon atoms, benzoyl or Carboxyl, and a process for preparing them, wherein naphthalene-1,4,5,8-tetracarboxylic acid, the mono- or dianhydride thereof are reacted as alkali salts in an aqueous solution with amines of the formula

Process for preparing naphthoylene-arylimidazo-peri-dicarboxylic acid-imide-compounds of the formula ##SPC1## Wherein R.sub.1 is hydrogen, hydroxy or amino, phenyl, alkyl having 1 to 8 carbon atoms, hydroxyalkyl, alkoxyalkyl, amino-alkyl, mono- or dialkylaminoalkyl, hydroxyalkoxyalkyl, alkoxyalkoxyalkyl, carbalkoxyalkyl, carboxylalkyl or phenyl-alkyl having each 1 to 6, preferably 1 to 4 carbon atoms in the alkyl or alkoxy portion and R is hydrogen or halogen, alkyl, alkoxy, carbalkoxy having each 1 to 4 carbon atoms, nitro, cyano, carbonamido, mono- or dialkylcarbonamido or sulfonamido, mono- or dialkylsulfonamido and n represents the integers 1 to 3, in which process naphthalimide-4,5-dicarboxylic acids of the general formula ##SPC2## Or the anhydride thereof are condensed in an aqueous medium with a diamine of the general formula ##SPC3## At temperatures of from 80.degree. to 160.degree.C. R.sub.1, R and n having the above meanings.

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Selters, Germany

Adolf Kroh