EP1517962A1

EP1517962A1 - Method for producing disazo pigments

Info

Publication number: EP1517962A1
Application number: EP03735467A
Authority: EP
Inventors: Olaf Schupp; Felix W. Grimm; Manfred Opravil; Joachim Weber
Original assignee: Clariant GmbH
Current assignee: Clariant Produkte Deutschland GmbH
Priority date: 2002-06-20
Filing date: 2003-05-27
Publication date: 2005-03-30
Also published as: US20060167236A1; WO2004000947A1; DE10227527A1; US7262284B2; JP2005535738A; CN1662610A; CN1305971C

Abstract

The invention relates to a method for the production of disazo pigments of general formula (I) or a mixture of said disazo pigments by means of azocoupling, wherein R1 and R2 are the same or different and represent hydrogen Cl-C4-alkyl, Cl-C4 alkoxy, CI-C5-alkoxycarbonyl, nitro, cyano, halogen, phenoxy or trifluoromethyl; D1 and D2 are the same or different and represent an aromatic heterocycle from the group ofbenzimidazole, benzimidazolone, benzimidazolthione, benzoxazole, benzoxazolone, benzothiazolone, indazole, phthalimide, naphthalimide, benzotriazole, chinoline, benzodiazines, phenmorpholine, phenmorpholinone, benzo[c,d]indolone, benzimidazo[1,2-a]pyrimidone, carbazole and indole. The invention is characterised in that the coupling product resulting from the azocoupling is subjected to a finish in an organic solvent with an alkaline pH value or in an aqueous organic solvent with a neutral or alkaline pH value.

Description

description

Process for the preparation of disazo pigments

The present invention relates to a new process for the preparation of disazo pigments with heterocyclic bases as the diazo component.

Some disazo pigments occur in their synthesis as finely divided prepigments that when sintered they sinter to hard and coarse-grained powders that can no longer be satisfactorily dispersed. In order to bring them into a form that can be used in application technology, the fine particles have to be subjected to a crystal growth process by means of a finish.

DE-A-24 51 097 discloses disazo pigments with heterocyclic bases as the diazo component and a process for the preparation of these disazo pigments.

DE-A-23 29 781 discloses disazo pigments with aminobenzoxazinediones as the diazo component. Pigments in this class have low color strengths.

DE-A-42 25 295 discloses disazo pigments with aminophenyl-benzothiazole as the diazo component. Pigments in this class have poor lightfastness.

DE-A-42 29 207 discloses a process for producing disazo pigments, characterized in that a surfactant with a cloud point is used. The use of the pigments produced according to the invention is limited to use in printing inks.

When using pigments for coloring high molecular weight organic materials, high demands are placed on the application properties of the pigments, such as high

Color strength, good light and weather fastness, in the case of use in paint systems, perfect over-paint fastness, high gloss, low viscosity of the highly pigmented paint concentrates (millbase) and the ready-to-use paints, and high transparency and brilliant colors, especially in the case of metallic paintwork. In the case of coloring plastics, in addition to the coloristics and fastness properties such as fastness to bleeding, good dispersibility is particularly required. Among other things, high color strengths and gloss are decisive in printing systems. The pigments should be used as universally as possible.

The disazo pigments prepared by the known processes with heterocyclic bases as the diazo component partly do not meet today's requirements, and partly they are not universally applicable.

There was a need for improvement and therefore the task of finding a process for producing disazo pigments with heterocyclic bases which provides pigments which meet today's requirements and whose use is not restricted to a single area of application.

It has been found that, surprisingly, the object is achieved by a finish in aqueous-organic solvent at neutral or alkaline pH, or in organic solvent at alkaline pH.

The invention relates to a process for the preparation of disazo pigments of the general formula (I)

or a mixture of said disazo pigments by azo coupling, wherein

R ¹ and R ^{2 are the} same or different and are hydrogen, CC ₄ alkyl, CC ₄ alkoxy, Ci-Cs-alkoxycarbonyl, nitro, cyano, halogen, phenoxy or trifluoromethyl; D ¹ and D ^{2 are the} same or different and are an aromatic heterocycle from the group benzimidazole, benzimidazolone, benzimidazolthione, benzoxazole, benzoxazolone, benzothiazolone, indazole, phthalimide, naphthalimide, benzotriazole, quinoline, benzodiazines, phenmorpholine, benzmidoline, phenmorpholinone indolone, benzimidazo [1, 2-a] pyrimidone,

Carbazole and indole, wherein said heterocycles are unsubstituted or by 1, 2, 3 or 4 identical or different radicals from the group halogen, C 1 -C ₄ alkyl, acetamido, carbomethoxyamino, CrC alkoxy, nitro, phenyl, phenoxy or Trifluoromethyl are substituted, where the phenyl radical can be substituted by chlorine, methyl or methoxy; and wherein said heterocycle is linked directly or through a phenylene group to the azo group in formula (I);

characterized in that the result of the azo coupling

Coupling product is subjected to a finish in organic solvent at alkaline pH, or in aqueous-organic solvent at neutral or alkaline pH.

R ¹ and R ² are preferably identical or different and are hydrogen, methyl, ethyl, methoxy, ethoxy, propoxy, butoxy, fluorine, chlorine, bromine, cyano, nitro, methoxycarbonyl, ethoxycarbonyl or trifluoromethyl.

Preferred aromatic heterocycles are those from the group benzimidazolone, phthalimide, naphthalimide and benzodiazines, such as quinazoline, quinazolinone, quinazolinedione, phthalazine, phthalazinone, phthalazinedione, quinoxaline, quinoxalinone and quinoxalinedione.

The heterocycles D ¹ and D ² are preferably unsubstituted or substituted by 1, 2 or 3 identical or different radicals from the group methyl, ethyl, methoxy, ethoxy, nitro, fluorine, chlorine, bromine, phenyl or trifluoromethyl. The general formula (I) is to be understood as an idealized formula and also includes the corresponding tautomeric compounds and the possible ones Configuration isomers of any tautomeric form. In the rings of D ¹ and D ^2, for example, -NH-CO groups can also be present in various tautomeric forms. The disazo pigments of the general formula (I) are normally in the hydrazone form. The general formula (I) therefore primarily includes the bishydrazone form.

The coupling product is expediently azo-coupled from one or more diazotized amines of the formula D-NH ₂ , in which D has the abovementioned meaning D ¹ or D ² , advantageously with 0.45 mol to 0.55 mol, preferably 0.5 to 0, 53 mol, per mol of the total diazonium salts to be reacted, one or more coupling components of the general formula (III)

wherein R ¹ and R ^{2 have} the meaning given above.

Coupling products which are prepared by coupling only a diazotized amine of the formula D-NH ₂ are preferably used, so that pigments of the general formula (I) are obtained in which D ¹ and D ^{2 have} the same meaning.

In particular, coupling products are used which have been prepared by coupling only one diazotized amine of the formula D-NH ₂ with only one coupling component of the general formula (IV), wherein

R ¹ and R ^{2 are the} same or different and are hydrogen, methyl, methoxy, chlorine or trifluoromethyl, so that pigments of the general formula (I) are obtained in which D ¹ and D ^{2 have} the same meaning.

Examples of amines of the formula D-NH ₂ are heterocyclic amines from the group benzimidazole, benzimidazolone, benzimidazolthione, benzoxazole, benzoxazolone, benzothiazolone, indazole, phthalimide, naphthalimide, benzotriazole, quinoline, benzodiazines, such as quinazoline, quinazolinone, quinazoline, quinazolinone, quinazolinone, Phthalazinedione, quinoxaline, quinoxalinone and quinoxalinedione, phenmorpholine, phenmorpholinone, benzo [c, d] indolone, benzimidazo [1,2-a] pyrimidone, carbazole and indole, where the heterocycles can be unsubstituted or substituted by the radicals mentioned above, for example 4 -Amino-6-chlorobenzimidazole, 4-amino-6-chloro-2-methylbenzimidazole, 5-amino-2-acetamidobenzimidazole, 5-amino-2-carbomethoxyaminobenzimidazole, 5-aminobenzimidazol-2-one, which is in the 6-position by methyl , Ethyl, methoxy, ethoxy, nitro, fluorine, chlorine, bromine or trifluoromethyl may be substituted; 5-aminobenzimidazol-2-one, which can be substituted in the 7-position by methyl, ethyl, methoxy, ethoxy, nitro, fluorine, chlorine, bromine or trifluoromethyl; 5-amino-1-methylbenzimidazol-2-one, 5-amino-1-p-chlorophenylbenzimidazol-2-one, 5-amino-1-p-methoxyphenylbenzimidazol-2-one, 5-amino-1-ethylbenzimidazol-2- on, 5-amino-3-methylbenzimidazol-2-one, 5-amino-4,6-dichlorobenzimidazol-2-one, 5-amino-4,6,7-trichlorobenzimidazol-2-one, 6-amino-4- chloro-5-nitrobenzimidazol-2-one, 7-amino-5-chloro-1-methylbenzimidazol-2-one, 5-amino-6-methylbenzimidazol-2-thione; 5-amino-7-chlorobenzoxazol-2-one, 6-amino-5-chlorobenzoxazol-2-one; 6-Amino-benzothiazol-2-one; 3-amino-6-chloroindazole, 5-aminoindazole, 6-aminoindazole, 5-aminophthalimide, 3-amino-1, 8-naphthalimide, 5-amino-2- (2-hydroxyphenyl) benzotriazole, 6-amino-2-hydroxy-4-methyl-quinoline, which is additionally represented by 5 -Methyl, 7-chloro, 7 -methyl, 7-ethoxy, 8-methyl or 8-methoxy may be substituted, especially 6-amino-5-chloro-4,8-dimethyl-2-hydroxyquinoline, 6-amino-8 - Chloro-4,5-dimethyl-2-hydroxyquinoline, 6-amino-5,8-dimethoxy-4-methyl-2-hydroxyquinoline, 6-amino-5-chloro-4-methyl-8-methoxy-2-hydroxyquinoline , 6-amino-4,5,8-trimethyl-2-hydroxyquinoline and 6-amino-5,8-dimethyl-2-hydroxyquinoline; 7-aminoquinoline, 7-amino-2-hydroxyquinoline, 7-amino-2-hydroxy-4-methylquinoline, which additionally by 6-nitro, 6-methoxy, 6-isopropoxy, 6-butoxy, 6-methyl or 6-chlorine , 5-chlorine or 5-methyl may be substituted, in particular 7-amino-2-hydroxy-4-methylquinoline and 7-amino-2-hydroxy-4-methyl-6-methoxyquinoline; 6-amino-2-methyl-quinazolin-4-one, 6-amino-7-chloro-2-methyl-quinazolin-4-one, 6-amino-2 (4'-methoxyphenyl) -quinazolin-4-one, 2- (4'-amino-3'-chlorophenyl) quinazolin-4-one; 6-amino-8-chlorphenmorpholin-3-one; 7-amino-6-methylphenmorpholin-3-one; 6-amino-quinazoline-2,4-dione, 6-amino-3-methylquinazoline-2,4-dione, 6-amino-7-nitroquinazoline-2,4-dione, 6-amino-7-chloro-quinazoline- 2,4-dione, 6-amino-8-nitroquinazoline-2,4-dione, 7-amino-quinazoline-2,4-dione and 7-amino-6-nitroquinazoline-2,4-dione; 6-amino-phthalazin-1,4-dione; 6-amino-quinoxaline-2,3-dione, which is optionally substituted in the 7-position by methyl, ethyl, methoxy, ethoxy, nitro, fluorine, chlorine, bromine or trifluoromethyl, in particular 6-amino-5,7-dichloroquinoxaline 2,3-dione and 6-amino-5,7,8-trichloroquinoxaline-2,3-dione, 7-amino-5-chloroquinoxaline-2,3-dione and 8-amino-6-chloro-1-methylquinoxaline- 2,3-dione; 3-aminocarbazole, 3-amino-N-ethyl-carbazole, and aminobenzo [c, d] indol-2-one, 7- and 8-amino-4-methyl-benzimidazo [1, 2-a] pyrimid-2 -one.

Particularly preferred examples of amines of the formula D-NH ₂ are 5-aminobenzimidazol-2-one, which in the 6-position additionally by methyl, methoxy, chlorine, nitro or trifluoromethyl and in the 1- and / or 3-position additionally by methyl or Ethyl may be substituted; 6-aminoquinoxaline-2,3-dione, which can additionally be substituted in the 7-position by methyl, methoxy, chlorine, nitro or trifluoromethyl and in the 1- and / or 4-position additionally by methyl or ethyl, 6-aminoquinazoline-2 , 4-dione, which is additionally in the 7-position by methyl, Methoxy, chlorine, nitro or trifluoromethyl and in the 1- and / or 3-position can additionally be substituted by methyl or ethyl.

Examples of coupling components are 1, 4-bis (acetoacetylamino) benzene, 2-fluoro-1, 4-bis (acetoacetylamino) benzene, 2-chloro-1, 4-bis (acetoacetylamino) benzene, 2-bromo-1, 4 bis (acetoacetylamino) benzene, 2-trifluoromethyl-1,4-bis (acetoacetylamino) benzene, 2-cyano-1,4, bis (acetoacetylamino) benzene, 2-methyl-1,4, bis (acetoacetylamino) benzene , 2-methoxy-1,4-bis (acetoacetylamino) benzene, 2-ethoxy-1,4-bis (acetoacetylamino) benzene, 2-phenoxy-1,4, bis (acetoacetylamino) benzene, 2-nitro-1,4 bis (acetoacetylamino) benzene, 2,5-dichloro-1,4-bis (acetoacetylamino) benzene, 2,5-dimethyl-1,4, bis (acetoacetylamino) benzene, 2,5-dimethoxy-1,4 bis (acetoacetylamino) benzene, 2,5-diethoxy-1,4-bis (acetoacetylamino) benzene, 2-ethoxy-5-methoxy-1,4-bis (acetoacetylamino) benzene, 2-chloro-5-methyl-1 , 4-bis (acetoacetylamino) benzene, 2-chloro-5-methoxy-1, 4-bis (acetoacetylamino) benzene, 2-chloro-5-ethoxy-1, 4- bis (acetoacetylamino) benzene, 2-methyl-5 -methoxy-1,4-bis (acetoacetylamino) benzene and 2-methyl-5-ethoxy-1,4-bis (Acetoacetylamino) benzene.

Particularly preferred coupling components are 1,4-bis (acetoacetylamino) benzene, 2-methyl-1,4-bis (acetoacetylamino) benzene, 2,5-dimethyl-1,4-bis (acetoacetylamino) benzene, 2-chloro-1 , 4-bis (acetoacetylamino) benzene,

2,5-dichloro-1,4-bis (acetoacetylamino) benzene, 2-chloro-5-methyl-1,4-bis (acetoacetylamino) benzene, 2-trifluoromethyl-1,4, bis (acetoacetylamino) benzene and 2- Methoxy-1,4-bis (acetoacetylamino) benzene.

The coupling product can be prepared by one of the customary methods, for example in an aqueous medium by means of an azo coupling reaction, by adding a) the diazonium salt to the coupling component (direct coupling) or b) the coupling component to the diazonium salt (indirect coupling), or c) it can also the diazonium salt and the coupling component by means of a mixing nozzle, a microreactor or a microjet reactor can be mixed with one another by simultaneous, continuous feeding.

Both the diazonium salt and the coupling component can be dissolved or used as a suspension, in the case of indirect coupling it is also customary to add the coupling component in solid form. The coupling component is preferably added as a freshly precipitated suspension to the diazonium salt present as a solution or suspension. It may be advantageous to carry out the coupling in the presence of customary coupling-promoting agents, such as, for example, long-chain amine oxides and phosphine oxides. By choosing the appropriate coupling method and parameters and, if necessary, by adding an agent that promotes the coupling, the conversion to the desired disazo coupling product can be optimized and the formation of mono coupling products can be minimized. Couplings in aqueous-organic or purely organic solvents can also be used to produce the coupling products. The process parameters essential for azo coupling, such as time, temperature, pH, use of buffers, solvents or surfactants, are known to the person skilled in the art from the literature. Usual pH values are 2 to 10. Usual temperatures are 0 to 75 ° C.

The coupling product used in the process according to the invention can be used both in the form of a press cake, preferably an aqueous-moist press cake, and in the dried state, for example as granules or powder.

In the process according to the invention, the finish of the coupling product is preferably carried out in a suspension which contains 1 to 50% by weight, preferably 2 to 20% by weight, in particular 3 to 17.5% by weight, of the coupling product, based on the total weight the suspension. Larger amounts of solvent can be used, but this can become uneconomical. With smaller amounts of solvent, the stirrability of the mixture can be impaired. Organic solvents for the finish are alcohols with 1 to 20, especially 1 to 10, carbon atoms, such as, for example, methanol, ethanol, n-propanol, isopropanol, butanols, such as n-butanol, iso-butanol, tert-butanol, pentanols , such as n-pentanol, 2-methyl-2-butanol, hexanols, such as 2-methyl-2-pentanol, 3-methyl-3-pentanol, 2-methyl-2-hexanol, 3-ethyl-3-pentanol, octanols such as 2,4,4-trimethyl-2-pentanol, cyclohexanol; or glycols, such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, or glycerin; Polyglycols, such as polyethylene or polypropylene glycols; Ethers such as methyl isobutyl ether, tetrahydrofuran, dimethoxyethane or dioxane; Glycol ethers, such as monoalkyl ethers of ethylene or propylene glycol or diethylene glycol monoalkyl ethers, where alkyl can be methyl, ethyl, propyl and butyl, butyl glycols or methoxybutanol; Polyethylene glycol monomethyl ether, especially those with an average molar mass of 350 to 550 g / mol, and polyethylene glycol dimethyl ether, especially those with an average molar mass of 250 to 500 g / mol; Ketones such as acetone, diethyl ketone, methyl isobutyl ketone, methyl ethyl ketone or cyclohexanone; aliphatic acid amides such as formamide, dimethylformamide, N-methylacetamide or N, N-dimethylacetamide; Urea derivatives such as tetramethyl urea; or cyclic carboxamides, such as N-methylpyrrolidone, valero- or caprolactam; Esters, such as CrC ₆ carboxylic acid alkyl esters, such as butyl formate, ethyl acetate or propyl propionate; or carboxylic acid Ci-Cβ glycol ester; or glycol ether acetates, such as 1-methoxy-2-propyl acetate; or phthalic or benzoic acid Ci-Cβ-alkyl esters, such as ethyl benzoate; cyclic esters such as caprolactone; Nitriles such as acetonitrile or benzonitrile; aliphatic or aromatic hydrocarbons, such as cyclohexane or benzene; or benzene substituted by alkyl, alkoxy, nitro or halogen, such as toluene, xylenes, ethylbenzene, anisole, nitrobenzene, chlorobenzene, o-dichlorobenzene, 1, 2,4-trichlorobenzene or bromobenzene; or other substituted aromatics such as benzoic acid or phenol; aromatic heterocycles such as pyridine, morpholine, picoline or quinoline; and also hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone; Sulfones and

Sulfoxides such as dimethyl sulfoxide and sulfolane; as well as mixtures of these solvents. When making your selection, please note that the solvent is stable under the selected conditions. In the case of an aqueous-organic solvent, at least 2.5% by weight, preferably at least 5% by weight, in particular at least 7.5% by weight, of the liquid phase is expediently organic solvent. Particularly preferred solvents are CrCβ alcohols, in particular methanol, ethanol, isopropanol, isobutanol and tert-butanol and tert-amyl alcohol, or butyl glycol, dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone or dimethyl sulfoxide.

An aqueous-organic solvent with 2.5 to 95% by weight, preferably 5 to 90% by weight, in particular 7.5 to 75% by weight, organic solvent, based on the total weight of the liquid phase, is preferred.

In the process according to the invention, the setting of an alkaline pH causes a change in the tautomeric form of the coupling product, but depending on the amount of base and the nature of the liquid phase, one or even multiple deprotonation of the coupling product with salt formation can also take place. Both are generally visible through a color change.

In order to adjust an alkaline pH, the bases are alkali metal hydroxides, optionally in the form of their aqueous solutions, such as sodium or potassium hydroxide, or alkali metal alcoholates, where alkali is in particular sodium or potassium, and the alcoholate is preferably derived from d-Cβ alcohols, such as for example sodium or potassium methanolate, ethanolate, isopropoxide, tert-butoxide and tert-amylate, are used. The alkali metal alcoholates can also be prepared in situ by reacting the corresponding alcohol with the alkali metal, alkali metal hydride or alkali metal amide.

The amount of base used can vary over a wide range. The change in tautomeric form generally takes place at pH> = 9, preferably greater than 9.5, in particular greater than 10.5, very particularly greater than 11.0, and the amount of the base must be chosen accordingly. The base can also be used in larger amounts for salt formation, for example 0.5 to 20 mol, preferably 0.5 to 15 mol, in particular 0.5 to 10 mol, based on 1 mol of the pigment. Also is a finish at even higher base concentrations possible, for example in up to 20 wt .-%, preferably up to 15 wt .-% base, based on the total weight of the liquid phase.

An aqueous-organic medium is preferably chosen at neutral or alkaline pH.

The finish in the process according to the invention is preferably at a temperature of 0 to 250 ° C., particularly 15 to 200 ° C., in particular 50 to 190 ° C., for a time of 5 minutes to 96 hours, particularly 5 minutes to 48 hours, in particular 5 Minutes to 24 hours, optionally carried out under increased pressure.

If the finish is carried out at alkaline pH, it is advisable to lower the pH again by adding acid before isolating the pigment. Organic acids such as e.g. aliphatic or aromatic carboxylic or sulfonic acids, such as formic acid, acetic acid, propionic acid, butyric acid, hexanoic acid, oxalic acid, citric acid, benzoic acid, phenylacetic acid, benzenesulfonic acid or p-toluenesulfonic acid, and inorganic acids such as e.g. Hydrochloric acid, sulfuric acid or phosphoric acid.

It is preferred to neutralize until an acidic pH is reached, but in principle it is sufficient to reverse the change in tautomeric form or deprotonation which has occurred as a result of the addition of the base.

The pigments are isolated in the usual way by filtration. Before the pigment is isolated, any solvent which may be used can be distilled, if appropriate under reduced pressure, or else by

Steam distillation can be removed.

The pigments produced by the process according to the invention can be used as preferably aqueous presscakes, but as a rule they are solid systems of free-flowing, powdery nature or granules. To improve the coloristic properties and to achieve certain application effects, auxiliaries such as, for example, surfactants, pigmentary and non-pigmentary dispersants, fillers, fillers, resins, waxes, defoamers, anti-dusting agents, extenders, colorants for shading, preservatives, drying retardants, additives for controlling the rheology, Wetting agents, antioxidants, such as flame retardants or deflagration-inhibiting agents, UV absorbers, light stabilizers, or a combination thereof can be used. Auxiliaries can be added at any time before, during or after the finish or grinding or after isolation, all at once or in several portions.

The total amount of auxiliaries added can be 0 to 40% by weight, preferably 1 to 30% by weight, particularly preferably 2.5 to 25% by weight, based on the pigment.

Suitable surfactants are anionic or anionic, cationic or cationic and nonionic substances or mixtures of these agents. Examples of anionic substances are fatty acid taurides, fatty acid N-methyl taurides, fatty acid isethionates, alkylphenyl sulfonates, alkylnaphthalenesulfonates, alkylphenol polyglycol ether sulfates,

Fatty alcohol polyglycol ether sulfates, fatty acid amide polyglycol ether sulfates, alkyl sulfosuccinamates, alkenyl succinic acid semiesters, fatty alcohol polyglycol ether sulfosuccinates, alkane sulfonates, fatty acid glutamates, alkyl sulfosuccinates, fatty acid sarcosides; Fatty acids, for example palmitic, stearic and oleic acid; Soaps, for example alkali salts of fatty acids,

Naphthenic acids and resin acids, for example abietic acid, alkali-soluble resins, for example rosin-modified maleate resins and condensation products based on cyanuric chloride, taurine, N, N'-diethylaminopropylamine and p-phenylenediamine. Resin soaps, i.e. Alkaline salts of resin acids.

Quaternary ammonium salts, fatty amine oxyalkylates, oxyalkylated polyamines, fatty amine polyglycol ethers, fatty amines, di- and polyamines derived from fatty amines or fatty alcohols, and the like, come as cation-active substances Oxalkylates, imidazolines derived from fatty acids, and salts of these cation-active substances, such as, for example, acetates. Examples of nonionic substances are amine oxides, fatty alcohol polyglycol ethers, fatty acid polyglycol esters, betaines such as fatty acid amide-N-propyl-betaine, phosphoric acid esters of aliphatic and aromatic alcohols, fatty alcohols or fatty alcohol polyglycol ethers, fatty acid amide ethoxylates, fatty alcohol-alkylene oxide adducts and alkylphenol adducts and alkylphenol into adducts and alkylphenol.

Nonpigmentary dispersants mean substances that are not structurally derived from organic pigments by chemical modification. They are added as dispersants either already during the production of pigments, but often also when the pigments are incorporated into the application media to be colored, for example in the production of lacquers or printing inks by dispersing the pigments in the corresponding binders. Polymeric substances, for example polyolefins, polyesters, polyethers, polyamides, polyimines, polyacrylates, polyisocyanates, block copolymers thereof, copolymers of the corresponding monomers or polymers of one class which have been modified with a few monomers of another class. These polymeric substances carry polar anchor groups such as, for example, hydroxyl, amino, imino and ammonium groups, carboxylic acid and carboxylate groups, sulfonic acid and sulfonate groups or phosphonic acid and phosphonate groups, and can also be modified with aromatic, non-pigmentary substances. Non-pigmentary dispersants can furthermore also be aromatic substances which are chemically modified with functional groups and are not derived from organic pigments. Nonpigmentary dispersants are known in the art and some are available commercially (for example, Solsperse ^®, Avecia; Disperbyk ^®, Byk, Efka ^®, Efka). A few types are to be mentioned in the following, but in principle any other substances described can be used, for example condensation products made from isocyanates and alcohols, di- or polyols, amino alcohols or di- or polyamines, polymers made from hydroxycarboxylic acids, copolymers Olefin monomers or vinyl monomers and ethylenically unsaturated carboxylic acids, esters, urethane-containing polymers of ethylenically unsaturated monomers, urethane-modified polyesters, condensation products based on cyanuric halides, polymers containing nitroxyl compounds, polyester amides, modified polyamides, modified acrylic polymers, comb dispersants made from polyesters and acrylic acid polymers, polymers, triazine polymers, phosphates, phosphates, phosphates modified polyethers, or dispersants derived from aromatic, non-pigmentary substances. These basic structures are often further modified, for example by chemical reaction with other functional groups or by salt formation.

By pigmentary dispersants are meant pigment dispersants which are derived from an organic pigment as the base body and are produced by chemical modification of this base body, for example saccharin-containing pigment dispersants, piperidyl-containing pigment dispersants, naphthalene or perylene-derived pigment dispersants, pigment dispersants with functional groups which have a methylene group with the Basic pigment bodies are linked, chemically modified basic pigment bodies, pigment dispersants containing sulfonic acid, sulfonamide or sulfonic acid ester groups, pigment dispersants containing ether or thioether groups, or pigment dispersants containing carboxylic acid, carboxylic acid ester or carbonamide groups.

It was surprising that the finish according to the invention allows the production of dispersible disazo pigments which, without this finish, can be produced after

Drying was previously difficult or impossible to disperse. The use of auxiliaries is not absolutely necessary in the process according to the invention for the preparation of the disazo pigments.

The use of the disazo pigments according to the invention is not restricted to one area of application. When dyeing high molecular weight organic materials, they are characterized by excellent application properties, in particular by very good dispersibility, good rheology, high color strength, perfect bleeding and bleeding Fastness to overcoating and very good light and weather fastness. Depending on requirements, opaque or transparent pigments can be produced and the color tone can be varied.

The pigments produced by the process according to the invention can be used for pigmenting high molecular weight organic materials of natural or synthetic origin, for example plastics, resins, lacquers, paints or electrophotographic toners and developers, as well as inks and printing inks.

High molecular weight organic materials that can be pigmented with the pigments mentioned are, for example, cellulose ethers and esters, such as ethyl cellulose, nitrocellulose, cellulose acetate or cellulose butyrate, natural resins or synthetic resins, such as polymerization resins or condensation resins, for example aminoplasts, in particular urea and

Melamine formaldehyde resins, alkyd resins, acrylic resins, phenoplasts, polycarbonates, polyolefins, such as polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyacrylonitrile, polyacrylic acid esters, polyamides, polyurethanes or polyesters, rubber, casein, silicone and silicone resins, individually or in mixtures. It does not matter whether the high-molecular organic compounds mentioned are present as plastic masses, melts or in the form of spinning solutions, lacquers, paints or printing inks. Depending on the intended use, it proves advantageous to use the pigments obtained according to the invention as a blend or in the form of preparations or dispersions. Based on the high-molecular organic material to be pigmented, the pigments according to the invention are used in an amount of 0.05 to 30% by weight, preferably 0.1 to 15% by weight.

The pigments produced according to the invention are also suitable as colorants in electrophotographic toners and developers, such as, for example, one- or two-component powder toners (also called one- or two-component developers), magnetic toners, liquid toners, polymerization toners and special toners. Typical toner binders are polymerization, polyaddition and polycondensation resins, such as styrene, styrene-acrylate, styrene-butadiene, acrylate, polyester, phenol-epoxy resins, polysulfones, polyurethanes, individually or in combination, and polyethylene and polypropylene, which also contain other ingredients, such as charge control agents, waxes or flow aids, or can be modified with these additives afterwards.

Furthermore, the pigments prepared according to the invention are suitable as colorants in powders and powder coatings, in particular in triboelectrically or electrokinetically sprayable powder coatings which are used for the surface coating of objects made of, for example, metal, wood, plastic, glass, ceramic, concrete, textile material, paper or rubber ,

Epoxy resins, carboxyl- and hydroxyl-containing polyester resins, polyurethane and acrylic resins are typically used as powder coating resins together with conventional hardeners. Combinations of resins are also used. For example, epoxy resins are often used in combination with carboxyl- and hydroxyl-containing polyester resins. Typical hardener components (depending on the resin system) are, for example, acid anhydrides, imidazoles and dicyandiamide and their derivatives, blocked isocyanates, bisacyl urethanes, phenolic and melamine resins, triglycidyl isocyanurates, oxazolines and dicarboxylic acids.

In addition, the pigments according to the invention are suitable as colorants in ink-jet inks on an aqueous and non-aqueous basis and in inks which work according to the hot-melt process.

Ink-jet inks generally contain a total of 0.5 to 15% by weight, preferably 1.5 to 8% by weight (calculated on a dry basis) of one or more of the compounds prepared according to the invention.

Microemulsion inks are based on organic solvents, water and possibly an additional hydrotropic substance (interface mediator). Microemulsion inks generally contain 0.5 to 15% by weight, preferably 1.5 to 8% by weight, of one or more of the compounds prepared according to the invention, 5 to 99% by weight of water and 0.5 to 94.5% by weight .-% organic solvent and / or hydrotropic compound. "Solvent-based" ink jet inks preferably contain 0.5 to 15% by weight of one or more compounds produced according to the invention, 85 to 99.5% by weight of organic solvent and / or hydrotropic compounds.

Hot-melt inks are usually based on waxes, fatty acids, fatty alcohols or sulfonamides, which are solid at room temperature and become liquid when heated, the preferred melting range being between approx. 60 ° C and approx. 140 ° C. Hot melt ink jet inks are e.g. essentially from 20 to 90% by weight of wax and 1 to 10% by weight of one or more of the compounds prepared according to the invention. Furthermore, 0 to 20% by weight of an additional polymer (as a "dye dissolver"), 0 to 5% by weight of dispersing aid, 0 to

Contain 20% by weight of viscosity modifier, 0 to 20% by weight of plasticizer, 0 to 10% by weight of tack additive, 0 to 10% by weight of transparency stabilizer (prevents, for example, crystallization of the waxes) and 0 to 2% by weight of antioxidant his. Typical additives and auxiliaries are e.g. in U.S. Patent 5,560,760.

Furthermore, the pigments produced according to the invention are also suitable as colorants for color filters both for additive and subtractive color production and for electronic inks.

Soft polyvinyl chloride (PVC) was selected from the large number of known plastics to assess the properties of the pigments in the plastics field.

To assess the properties of the pigments in the printing sector, a gravure printing system based on nitrocellulose (NC) was selected from the large number of known printing systems.

To assess the properties of the pigments in the lacquer sector, an alkyd-melamine resin lacquer (AM) based on a medium-oil alkyd resin and a butanol-etherified melamine resin was used from the large number of known lacquers High-solid acrylic stoving enamel based on a non-aqueous dispersion (HS) and an aqueous enamel based on polyurethane (PUR) selected.

The color strength and hue were determined in accordance with DIN 55986. The rheology of the mill base after dispersion (millbase rheology) was assessed visually using the following five-point scale.

5 thin

4 liquid

3 viscous

2 slightly stocked

1 stocked

The fastness to overcoating was determined in accordance with DIN 53221. The viscosity was determined after the millbase had been diluted to the final pigment concentration using the Rossmann viscose spatula, type 301 from Erichsen. Gloss measurements were carried out on film infusions at an angle of 20 ° in accordance with DIN 67530 (ASTMD 523) using the "multigloss" gloss meter from Byk-Mallinckrodt.

In the following examples, parts are parts by weight and percentages are percentages by weight.

example 1

a) Diazonium salt solution

35.5 parts of 6-amino-1H, 3H-quinazoline-2,4-dione are heated to boiling in 200 parts by volume of glacial acetic acid and 60 parts by volume of 31% hydrochloric acid are added dropwise. After the addition of 800 parts of water, the mixture is diazotized at 0 to 5 ° C. by adding 26 parts by volume of 40% sodium nitrite solution. After stirring for 90 minutes, make up to 2.5 liters with water. After clarification, excess nitrite is destroyed with sulfamic acid.

b) Solution of the coupling component 31.7 parts of 2-chloro-1,4-bis (acetoacetylamino) benzene are dissolved in 250 parts of water and 150 parts of ice by adding 24 parts by volume of 33% sodium hydroxide solution.

c) clutch

193.6 parts of 33% sodium hydroxide solution, 100 parts of water and 160 parts of ice are introduced and pH 7 to 7.5 is adjusted with glacial acetic acid. The diazonium salt solution is added, and a temperature of 7 to 10 ° C. is set with ice. The solution of the coupling component is allowed to run in in 15 min, then the mixture is heated to a temperature of 98 ° C. in the course of 4.5 hours with stirring. Filter at 80 ° C and wash the press cake with water. 507 parts of press cake with a solids content of 13.5% are obtained.

d) Finish 147.8 parts of presscake according to Example 1c) are stirred in 62.2 parts of water and 190 parts of N-methylpyrrolidone. At 60 ° C with 7.2 parts of 33% sodium hydroxide solution pH 12.3. The color of the suspension becomes darker from approx. PH 9.0 and changes from yellow to orange in the range of pH 10.5. The suspension is stirred under reflux for 5 hours, then the pH is adjusted to 1.5 using 31% hydrochloric acid. The color changes to greenish-yellow. It is filtered, washed with 50% aqueous N-methylpyrrolidone, then with water and dried at 80 ° C. 16.4 parts of pigment are obtained, which in the AM lacquer provides transparent colorations with a yellow hue.

Example 2

a) Diazonium salt solution

29.8 parts of 5-aminobenzimidazolone are mixed in 60 parts by volume of 31% hydrochloric acid and 500 parts of water at 50.degree. After cooling to 5 to 10 ° C., 40% sodium nitrite solution is diazotized by adding 26 parts by volume. After stirring for 1 hour, the volume is made up to 2.5 liters with water and, after clarification, excess nitrite is destroyed with sulfamic acid. b) Solution of the coupling component

27.6 parts of 1,4-bis (acetoacetylamino) benzene are dissolved in 400 parts of water by adding 30 parts by volume of 33% sodium hydroxide solution. After adding 160 parts of ice, 40% by volume of 50% acetic acid is precipitated.

c) clutch

193.6 parts of 33% sodium hydroxide solution, 100 parts of water and 160 parts of ice are introduced and pH 7 to 7.5 is adjusted with glacial acetic acid. The diazonium salt solution is added, and a temperature of 7 to 10 ° C. is set with ice. The suspension of the coupling component is allowed to run in in 35 min, then the mixture is heated to a temperature of 98 ° C. within 7 hours with stirring. Filter at 80 ° C and wash the press cake with water. 324 parts of press cake with a solids content of 19% are obtained.

d) finish

105.5 parts of the press cake according to Example 2c) are stirred in 104.5 parts of water and 190 parts of N-methylpyrrolidone. At 60 to 65 ° C., 6.7 parts of 33% sodium hydroxide solution are used to set pH 12.4, the color of the suspension changes from yellow to orange. After stirring for 5 hours under reflux, the pH is adjusted to 1.5 with 31% hydrochloric acid, the color changing to a reddish yellow. It is filtered, washed with 50% N-methylpyrrolidone, then with water and dried at 80 ° C. 11 parts of pigment are obtained which, in the AM lacquer, provide orange, opaque and strongly colored lacquers. The fastness to painting is flawless. Strong and glossy prints are obtained in NC printing.

Comparative Example 1

The chromophore from Example 2 was produced according to DE 24 51 097 Example 64. Comparison of example 2d) against comparison example 1

The lacquers in the AM lacquer of the pigment according to Example 2d) are significantly more intense, opaque and redder than those of Comparative Example 1. The rheology is rated 3, the viscosity is 3.4 seconds, the gloss of a drawn paint has a value of 78 and the gloss of a cast paint has a value of 80. In the case of Comparative Example 1, the rheology is rated 1, the Viscosity cannot be measured (thickened too much), the paintwork is so matt that a gloss cannot be measured or cast.

Example 3

a) diazonium salt solution: according to example 2a)

b) Solution of the coupling component: according to Example 1b)

c) clutch

193.6 parts of 33% sodium hydroxide solution, 100 parts of water and 160 parts of ice are introduced and pH 7 to 7.5 is adjusted with glacial acetic acid. The diazonium salt solution is added, and a temperature of 7 to 10 ° C. is set with ice. The solution of the coupling component is allowed to run in over 15 minutes, and the mixture is then heated to a temperature of 98 ° C. in the course of 3.5 hours. Filter at 80 ° C and wash the press cake with water. 735 parts of press cake with a solids content of 8.4% are obtained.

d) Alkaline finish

238 parts of press cake according to Example 3c) are stirred in 218 parts of N-methylpyrrolidone. The pH is adjusted to 12.4 with 4.4 parts of 33% sodium hydroxide solution at 60 ° C., the color of the suspension becoming noticeably darker from pH 10. After stirring for 5 hours under reflux, the pH is adjusted to 1.5 using 31% hydrochloric acid, and the color tone becomes light and orange again. It is filtered, washed with 50% N-methylpyrrolidone, then with water and dried at 80 ° C. 19.3 parts of pigment are obtained which, in the AM lacquer, provide orange, opaque and strongly colored lacquers. e) Neutral finish

238.1 parts of presscake according to Example 3c) are suspended in 71.9 parts of water and 290 parts of N-methylpyrrolidone and stirred at 150 ° C. for 5 hours. After cooling, it is filtered, washed with 50% N-methylpyrrolidone and then with water and dried at 80 ° C. 15.6 parts of pigment are obtained which, in the AM lacquer, provide orange, opaque and strongly colored lacquers.

Comparative Example 2

The chromophore from Example 3 was prepared according to DE 24 51 097 Example 1 by using 5-aminobenzimidazolone as the base and 2-chloro-1,4-bis (acetoacetylamino) benzene as the coupling component.

Comparison of example 3d) against comparison example 2

The coatings in the AM coating of the pigment according to Example 3d) are significantly more intense and redder than those of Comparative Example 2. The viscosity is 3.6 seconds, the gloss drawn has a value of 70 and the gloss cast has a value of 72. In the case of comparative example 2, the viscosity is 9.0 seconds, the gloss drawn has a value of only 32 and cast the varnish is so matt that a gloss can no longer be measured.

Comparison of example 3e) against comparison example 2

The coatings in the AM coating of the pigment according to Example 3e) are significantly more intense and redder and noticeably more opaque than those of Comparative Example 2. The viscosity is 5.8 sec, the gloss drawn has a value of 71 and the gloss cast has a value of 19. In the case of

Comparative example 2, the viscosity is 9.0 sec, the gloss drawn has a value of only 32 and the cast is so matt that a gloss is no longer measurable.

Example 4

a) diazonium salt solution: according to Example 1a) b) Solution of the coupling component: according to example 2b)

c) clutch

193.6 parts of 33% sodium hydroxide solution, 100 parts of water and 160 parts of ice are introduced and pH 7 to 7.5 is adjusted with glacial acetic acid. The diazonium salt solution is added, and a temperature of 7 to 10 ° C. is set with ice. The suspension of the coupling component is allowed to run in over 30 min, then the mixture is heated to a temperature of 98 ° C. in the course of 3 hours with stirring. Filter at 80 ° C and wash the press cake with water. 472.2 parts of press cake with a solids content of 12.7% are obtained.

d) finish

157.5 parts of press cake according to Example 4c) are stirred in 52.5 parts of water and 190 parts of N-methylpyrrolidone. At 60 ° C with 7.6 parts of 33% sodium hydroxide solution pH 12.5. The color of the suspension changes from greenish-yellow to reddish-yellow. The suspension is stirred under reflux for 5 hours, then the pH is adjusted to 2 with 31% hydrochloric acid. The color changes to greenish-yellow. It is filtered, washed with 50% aqueous N-methylpyrrolidone, then with water and dried at 80 ° C. 16.5 parts of pigment are obtained, which in the AM lacquer provides transparent colorations with a yellow hue.

Example 5

a) Diazonium salt solution

41.4 parts of 6-amino-7-methoxyquinoxaline-2,3-dione are stirred in 500 parts of water and 60 parts by volume of 31% hydrochloric acid. At 0 to 5 ° C, 40% sodium nitrite solution is diazotized by adding 26 parts by volume. After stirring for 45 min and subsequent clarifying filtration, excess nitrite is destroyed with sulfamic acid.

b) Solution of the coupling component: according to Example 1b) c) clutch

193.6 parts of 33% sodium hydroxide solution, 100 parts of water and 160 parts of ice are introduced and pH 7 to 7.5 is adjusted with glacial acetic acid. The diazonium salt solution is added, a temperature of 7 ° C. is set with ice. The solution of the coupling component is allowed to run in over 15 minutes, and the mixture is then heated to a temperature of 98 ° C. in the course of 2.5 hours. Filter at 80 ° C and wash the press cake with water. 641.7 parts of presscake with a solids content of 11.2% are obtained.

d) Alkaline finish

178.9 parts of presscake according to Example 5c) are stirred in 31.1 parts of water and 190 parts of N-methylpyrrolidone. At 60 ° C with 7.3 parts of 33% sodium hydroxide solution pH 12.2. The color of the suspension becomes darker from approx. PH 9.0 and changes from orange to red-brown in the pH 11 range. After adding 40 parts by volume of 50% N-methylpyrrolidone, the suspension is stirred under reflux for 5 hours, then the pH is adjusted to 1.5 using 31% hydrochloric acid. The color changes to reddish yellow. It is filtered, washed with 50% aqueous N-methylpyrrolidone, then with water and dried at 80 ° C. 19.1 parts of pigment are obtained which, in the AM varnish, provide covering colorations with a yellow hue.

e) Neutral finish

178.9 parts of presscake according to Example 5c) are suspended in 131.1 parts of water and 290 parts of N-methylpyrrolidone and stirred at 150 ° C. for 5 hours. After cooling, it is filtered, washed with 50% N-methylpyrrolidone and then with water and dried at 80 ° C. 19.4 parts of pigment are obtained, which in the AM lacquer provides red-tinged yellow and transparent lacquers.

Comparative Example 3 The chromophore from Example 5 was prepared according to DE 24 51 097 Example 1 by using 6-amino-7-methoxyquinoxaline-2,3-dione as the base and 2-chloro-1,4-bis (acetoacetylamino) benzene as the coupling component were. Comparison of example 5d) against comparison example 3

The lacquers in the AM lacquer of the pigment according to Example 5d) are significantly more intense and lighter in color, significantly more opaque, and also greener and purer than those of Comparative Example 3. The viscosity is 3.8 seconds, the gloss drawn has a value of 69 and the gloss cast has a value of 69. In the case of Comparative Example 3, the viscosity is 4.3 seconds, the gloss drawn has a value of only 27 and Cast gloss has a value of only 15.

Comparison of example 5e) against comparison example 3

The coatings in the AM coating of the pigment according to Example 5e) are significantly more intense in color, significantly lighter, somewhat more opaque and, in addition, greener than those of Comparative Example 3. The luster drawn has a value of 51 and the luster cast has a value of 38. In the case of Comparative Example 3, the luster drawn has a value of only 27 and the luster cast has a value of only 15.

Example 6

a) Diazonium salt solution

103.5 parts of 6-amino-7-methoxyquinoxaline-2,3-dione are stirred in 1250 parts of water and 150 parts by volume of 31% hydrochloric acid. At 0 to 5 ° C, 5N sodium nitrite solution is diazotized by adding 100 parts by volume. After stirring for 90 min and subsequent clarifying filtration, excess nitrite is destroyed with sulfamic acid.

b) Solution of the coupling component

69 parts of 1,4-bis (acetoacetylamino) benzene are dissolved in 1000 parts of water by adding 75 parts by volume of 33% sodium hydroxide solution. After adding 400 parts of ice, 50% acetic acid is precipitated by adding 100 parts by volume. c) clutch

484 parts of 33% sodium hydroxide solution, 250 parts of water and 400 parts of ice are introduced and the pH is adjusted to 6.9 to 7.0 with glacial acetic acid. The diazonium salt solution and 50 parts by volume of a 10% aqueous solution of a fatty alcohol polyglycol ether, prepared from a saturated C16-C18 alcohol by reaction with 25 equivalents of ethylene oxide, are added. The suspension of the coupling component is run in in 75 min, then the mixture is stirred at 95 to 98 ° C. for 3 hours. Filter at 80 ° C and wash the press cake with water. 1110 parts of press cake with a solids content of 16.8% are obtained.

d) Finish alkaline, organic solvent

89.1 parts of presscake according to Example 6c) and 0.4 part of solid sodium hydroxide are stirred in 333.3 parts of N-methylpyrrolidone. Then it is heated to 180 ° C. and water is distilled off. After 5 hours of stirring at 180 ° C., the mixture is cooled to 100 ° C. and adjusted to pH 1.5 by adding 31% hydrochloric acid. After stirring at 100 ° C. for 15 minutes, the mixture is filtered, washed with 50% N-methylpyrrolidone and then with water and dried at 80 ° C. 11 parts of pigment are obtained, which in the AM lacquer provides reddish-yellow and strong-colored lacquers.

e) alkaline finish, room temperature, aqueous-organic solvent 100 parts of press cake according to Example 6c) are in 220 parts of water,

Mix 340 parts of N-methylpyrrolidone and 13 parts of solid sodium hydroxide. The color changes from orange to brown and further to yellow. The suspension is stirred at room temperature for about 70 hours. The pH is adjusted to 1.5 with 31% hydrochloric acid, then the mixture is filtered, washed with 50% N-methylpyrrolidone, then with water and dried at 80.degree. 15.5 parts of pigment are obtained, which in the AM lacquer provides transparent and strongly colored lacquers with a pure, orange color. f) Alkaline finish, aqueous-organic solvent 120.1 parts of presscake according to Example 6c) are stirred in 175.6 parts of water. The pH is adjusted to 11 using 0.47 part of solid sodium hydroxide. After the addition of 275.7 parts of isobutanol, the mixture is stirred at 150 ° C. under pressure for 10 hours. After cooling, the pH is adjusted to 1.5 with 31% hydrochloric acid. The mixture is then stirred under reflux for 1 hour and then the alcohol is removed by passing steam through it. After filtration and washing with water, the mixture is dried at 80 ° C. 18.2 parts of pigment are obtained, the yellow and strong-colored coatings in the AM lacquer.

g) Finish alkaline, aqueous-organic solvent 100 parts of presscake according to Example 6c) are mixed in 191, 4 parts of water and 274.8 parts of N-methylpyrrolidone. The pH is adjusted to 11.1 using 1.42 parts of 33% sodium hydroxide solution. The mixture is stirred under pressure at 130 ° C. for 12 min. After cooling to 50 ° C., the pH is adjusted to 1.5 using 31% hydrochloric acid. After filtration and washing with water, the mixture is dried at 80 ° C. 16.5 parts of pigment are obtained, which in the AM lacquer provides reddish-yellow and strong-colored lacquers.

h) Finish alkaline, aqueous-organic solvent 118.8 parts of presscake according to Example 6c) are stirred in 221 parts of water and 340 parts of N-methylpyrrolidone. The pH is adjusted to 10.8 with 0.56 part of solid sodium hydroxide. The mixture is stirred under pressure at 170 ° C. for 5 hours. After cooling to 50 ° C., the pH is adjusted to 1.5 using 31% hydrochloric acid. After filtration and washing with 50% N-methylpyrrolidone and water, the mixture is dried at 80 ° C. 16.6 parts of pigment are obtained, which in the AM lacquer provides yellow and strongly colored lacquers.

i) Alkaline finish, aqueous organic solvent

120.1 parts of press cake according to Example 6c) are stirred in 175.6 parts of water and 275.7 parts of N-methylpyrrolidone. Then within

A total of 2.8 parts of solid sodium hydroxide were added in portions over the course of 12 hours, while stirring under reflux. The pH is then adjusted to 1.5 using 31% hydrochloric acid, the mixture is stirred under reflux for 15 min and, after cooling, filtered with 50% N-methylpyrrolidone and washed with water and dried at 80 ° C. 19.4 parts of pigment are obtained, which in the AM lacquer provides orange and strongly colored lacquers.

k) Finish neutral, aqueous-organic solvent

118.8 parts of presscake according to Example 6c) are stirred in 221 parts of water and 340 parts of N-methylpyrrolidone. Without addition of alkali, the mixture is stirred under pressure at 170 ° C. for 5 hours. After cooling, the mixture is filtered, washed with 50% N-methylpyrrolidone and with water and dried at 80 ° C. 17 parts of pigment are obtained, which in the AM lacquer provides reddish-yellow and strong-colored lacquers.

Comparative Example 4

The chromophore from Example 6 was prepared according to DE 24 51 097 Example 1 by using 6-amino-7-methoxyquinoxaline-2,3-dione as the base and

Coupling component 1, 4-bis (acetoacetylamino) benzene were used.

Comparison of comparative example 4 against example 6h)

The coatings in the AM coating of the pigment according to Comparative Example 4 are significantly weaker in color and redder and significantly more transparent than those in Example 6h. The gloss drawn only has a value of 31 and the gloss cast has a value of only 22. The paintwork of example 6h) is significantly more shiny: the gloss drawn has a value of 77 and the gloss cast has a value of 76.

Comparison of comparative example 4 against example 6i)

The coatings in the AM coating of the pigment according to Comparative Example 4) are significantly weaker in color, more transparent and more yellow than those in Example 6i). The gloss drawn has a value of only 31 and the gloss cast has a value of only 22. The paintwork of example 6i) is significantly glossier: the gloss both drawn and cast has a value of 64. Comparison of comparative example 4 against example 6k)

The coatings in the AM coating of the pigment according to Comparative Example 4 are significantly weaker in color and significantly redder and significantly more transparent than those in Example 6k. The gloss drawn has a value of only 31 and the gloss cast has a value of only 22. The paintwork of example 6k) is significantly glossier: the gloss drawn has a value of 61 and the gloss cast has a value of 52.

Comparative Example 5 The chromophore from Example 2 was produced according to DE-A-42 29 207 Example 29.

Comparison of comparative example 5 against example 2d):

The pigments prepared according to Example 2d) and Comparative Example 5 were incorporated into a PVC plastic. The colorations of Example 2d) are strong in color and have a pure, reddish-yellow hue. The pigment from Comparative Example 5 is not dispersed, only black specks can be seen. The PVC is not stained. The pigment is completely unsuitable for coloring PVC. Both pigments were compared in an AM lacquer. The pigment from comparative example 5 shows a dark, cloudy full tone and is significantly weaker in color than the pigment from example 2d), which provides a pure, light full tone.

Claims

claims:

1) Process for the preparation of disazo pigments of the general formula (I)

or a mixture of said disazo pigments by azo coupling, in which R ¹ and R ^{2 are} identical or different and are hydrogen, C 1 -C ₄ alkyl, C 1 -C ₄ alkoxy, Ci-Cs-alkoxycarbonyl, nitro, cyano, halogen, phenoxy or trifluoromethyl;

D ¹ and D ^{2 are the} same or different and are an aromatic heterocycle from the group benzimidazole, benzimidazolone, benzimidazolthione, benzoxazole, benzoxazolone, benzothiazolone, indazole, phthalimide, naphthalimide, benzotriazole, quinoline, benzodiazines, phenmorpholine, benzmidoline, phenmorpholinone indolone, benzimidazo [1,2-a] pyrimidone,

Carbazole and indole, wherein said heterocycles are unsubstituted or substituted by 1, 2, 3 or 4 identical or different radicals from the group halogen, CrC-alkyl, acetamido, carbomethoxyamino, Cr C ₄ -alkoxy, nitro, phenyl, phenoxy or trifluoromethyl , where the phenyl radical can be substituted by chlorine, methyl or methoxy; and wherein said heterocycle is connected to the azo group in formula (I) directly or through a phenylene group;

characterized in that the result of the azo coupling

Coupling product is subjected to a finish in organic solvent at alkaline pH or in aqueous-organic solvent at neutral or alkaline pH. 2) Method according to claim 1, characterized in that R ¹ and R ^{2 are the} same or different and hydrogen, methyl, ethyl, methoxy, ethoxy, propoxy, butoxy, fluorine, chlorine, bromine, cyano, nitro, methoxycarbonyl, ethoxycarbonyl or trifluoromethyl mean.

3) Method according to claim 1, characterized in that the aromatic heterocycle is a benzimidazolone, phthalimide, naphthalimide, quinazoline, quinazolinone, quinazolinedione, phthalazine, phthalazinone, phthalazinedione, quinoxaline, quinoxalinone or quinoxalinedione.

4) Method according to one or more of claims 1 to 3, characterized in that the heterocycles D ¹ and D ^{2 are} unsubstituted or substituted by 1, 2 or 3 identical or different radicals from the group methyl, ethyl, methoxy, ethoxy, nitro, Are fluorine, chlorine, bromine, phenyl or trifluoromethyl.

5) Method according to one or more of claims 1 to 4, characterized in that the coupling product is used in the form of a press cake, as granules or as a powder.

6) Method according to one or more of claims 1 to 5, characterized in that the finish of the coupling product is carried out in a suspension which 1 to 50 wt .-%, preferably 2 to 20 wt .-%, in particular 3 to 17, 5 wt .-%, of the coupling product, based on the total weight of the suspension contains.

7) Method according to one or more of claims 1 to 6, characterized in that the organic solvent for the finish an alcohol with 1 to 20 carbon atoms, a glycol, glycerol, a polyglycol, an ether, a glycol ether, a ketone, an aliphatic acid amide, a urea derivative, a cyclic carboxylic acid amide, an ester of an aliphatic or aromatic carboxylic acid, a nitrile, an aliphatic, aromatic or araliphatic hydrocarbon, a benzene substituted by alkyl, alkoxy, nitro, hydroxy, carboxy and / or halogen, an aromatic Heterocycle, hexamethylphosphoric triamide, 1, 3- Dimetyl-2-imidazolidinone; a sulfone, a sulfoxide; or a mixture of these solvents.

8) Method according to one or more of claims 1 to 7, characterized in that the organic solvent for the finish a Ci-Ce alcohol, in particular methanol, ethanol, isopropanol, isobutanol, tert-butanol or tert-amyl alcohol, or Butylglycol, dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone or dimethyl sulfoxide, or a mixture thereof.

9) Method according to one or more of claims 1 to 8, characterized in that the aqueous-organic solvent contains 2.5 to 95 wt .-%, preferably 5 to 90 wt .-%, organic solvent.

10) Method according to one or more of claims 1 to 9, characterized in that in the case of a finish at alkaline pH, the pH is at least 9, preferably greater than 9.5.

11) Method according to one or more of claims 1 to 10, characterized in that the finish is carried out at a temperature between 0 and 250 ° C, preferably between 15 and 200 ° C.

12) Method according to one or more of claims 1 to 11, characterized in that the finish is carried out for a period of 5 minutes to 96 hours.

13) Method according to one or more of claims 1 to 12, characterized in that an acid is added following a finish at alkaline pH.