GB1561187A - Water-insoluble dyestuff formulations - Google Patents

Abstract

The novel aqueous preparations of water-insoluble dyes containing water-soluble N-hydroxyalkylureas which can be obtained conveniently by reacting alkanolamines with compounds containing isocyanate groups, in an aqueous phase. These N-hydroxyalkylureas serve to prevent drying-out and act as stabilizers against flocculation; they do not significantly increase the viscosity of the preparation. The preparations can in particular be used as printing inks for the preparation of print carriers for transfer printing; in that case, they contain sublimable dyes.

Description

(54) WATER-INSOLUBLE DYESTUFF FORMULATIONS (71) We, BAYER AKTIENGESELLSCHAFT, a body corporate organised and existing under the laws of Germany, of Leverkusen, Federal Republic of Germany, do hereby declare, the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:: The invention relates to aqueous formulations of water-insoluble dyestuffs (as hereinafter defined), which are characterised in that they contain water-soluble N-hydroxyalkylureas which correspond to the formula

wherein R is an n-valent alkyl, cycloalkyl or aryl radical which is optionally substituted and optionally interrupted by hetero-atoms, such as that which remains after removing n-isocyanate groups from a corresponding n-valent isocyanate, R1 represents an alkylene radical having at least two carbon atoms, R2 represents hydrogen, an alkyl radical or the radical -R1OH and n represents a number from 1 to 5.

Suitable alkyl radicals R are those with 1 to 18 C atoms; suitable cycloalkyl radicals R are those with 5 or 6 ring carbon atoms and suitable aryl radicals R are phenyl and naphthyl radicals, it being possible for the radicals mentioned to contain, for example, urethane, urea, uretdione, biuret or isocyanuric acid radicals. The aryl radicals and cycloalkyl radicals can preferably carry Cl-C4 -alkyl substituents or chlorine substituents.

Preferred ureas are those of the formula (I), wherein R represents an n-valent C1-C6-alkyl radical which is optionally interrupted by urea or biuret groups, a cyclohexyl or cyclopentyl radical which is optionally substituted by methyl groups or a phenyl radical which is optionally substituted by C1-C4-alkyl, chlorine, bromine, fluorine or C1-C4-alkoxy, Rl represents

R2 represents H or Rl.

R3 represents H or CH3 and n represents 1, 2 or 3.

Particularly preferred radicals R which remain after removing one isocyanate group are the methyl, cyclohexyl and phenyl radicals, and preferred radicals R which remain after removing two isocyanate groups are the hexamethylene, the cyclohexylene and the phenylene radical, it being possible for the radicals listed to be substituted by 1 to 3 methyl groups. Preferred radicals R which remain after removing three isocyanate groups are alkylene, cycloalkylene and arylene radicals, containing urethane, urea or biuret groups.

The following, particularly suitable N-hydroxyalkyl-ureas may be mentioned as examples:

(wherein R3 = H or CH3; and R2 = H or

The following agent for preventing drying out is very particularly preferred:

Some of the hydroxyalkylureas to be used according to the invention are known from the literature, for example in DOS (German Published Specification) 2,106,726, or they can be prepared from hydroxyalkylamines compounds containing isocyanate groups according to customary processes which are known from the literature (Houben-Weyl, Volume 8, page 157-158).

In this procedure, the reactions can be carried out without a solvent or in solvents, advantageously in water.

Suitable aliphatic, cycloaliphatic and aromatic compounds containing isocyanate groups which may be mentioned are: 1 ,4-cyclohexane diisocyanate, phorone diisocyanate (1,6-(2,2,4- and 2,4,4-trimethyl-hexamethylene) diisocyanate), 1,3-cyclopentylene diisocyanate, m- and p-phenylene diisocyanate, 2,4,6-toluylene triisocyanate, 4,4'-, 1,3- and 1 ,4-xylylene diisocyanate, durene diisocyanate, 1-tert. -butyl-2,4-phenylene diisocyanate, 1-chloro-2,4-phenylene diisocyanate and preferably, however, phenyl isocyanate, methyl isocyanate, cyclohexyl isocyanate, hexamethylene diisocyanate, 2,4- and 2,6-toluylene diisocyanate and mixtures thereof, isophorone diisocyanate (1-isocyanatomethyl-5 isocyanato-1 ,3,3-trimethylcyclohexane) ,3 ,3-trimethylcyclohexane).

According to a method of synthesis for the preparation of higher polyisocyanates, it is possible to prepare, by partial hydrolysis of diisocyanates or polyisocyanates, via the stage of the carbamic acid and the amine, higher urea-linked or biuret-linked systems, for example, a biuret-linked compound which is formally formed from 3 mols of hexamethylene diisocyanate, with the addition of 1 mol of water and splitting off of 1 mol of carbon dioxide. The polyisocyanate thus obtained is suitable for the preparation of preferred hydroxyalkylureas.

Substances, containing isocyanate groups, which are also suitable are obtained by reacting diols or polyols with difunctional or polyfunctional isocyanates, if the molar ratio of hydroxy compound to isocyanate is chosen so that free NCO groups always remain present in the statistically formed reaction products, that is to say, for example, reaction products of 1 mol of trimethylolpropane and 3 mols of toluylene diisocyanate or isophorone diisocyanate.

As used herein the term "water-insoluble dyestuff" includes pigments and optical brighteners.

Possible water-insoluble dyestuffs are, for example: 1. Pigments for example, organic pigments of the azo, anthraquinone, azoporphine, thioindigo or polycyclic series, and also of the quinacridone, dioxazine, naphthalenetetracarboxylic acid or perylenetetracarboxylic acid series, such as are known from the Colour Index, 2nd edition, or inorganic-pigments, such as zinc sulphides, cadmium sulphides or selenides, ultramarine, titanium dioxide, iron oxides, nickel or chromium titanium yellow, chromium oxides, chromate pigments and carbon black as well as their mixtures.

2. Disperse dyestuffs. These include polyester and polyamide dyestuffs which are insoluble or virtually insoluble in water, in particular those of the azo, anthraquinone, methine, quinophthalone and aminocoumarine series, such as are listed, for example, in the Colour Index, 3rd edition (1971), volume 2, page 2,483-2,741. Water-insoluble optical brighteners, such as those of the coumarine, stilbene, naphthalimide or carbostyryl series, are also disperse dyestuffs in the sense of this invention.

These include, preferably. dyestuffs which sublime in the range from 160-220"C, such as are customarily used in transfer printing (compare, for example, British Patent Specification 1,221,126).

Examples which may be mentioned are: C.I. Disperse Yellow 60 No. 12,712, C.I.

Disperse Yellow 3 No. 11,855, C.I. Disperse Red 5 No. 11,215, C.I. Disperse Red 13 No.

11,115, C.I. Disperse Red 4 No. 60,755, C.I. Disperse Violet 1 No. 61,100, C.I. Disperse Blue 19 No. 61,110, C.I. Disperse Blue 14 No. 61,500, C.I. Disperse Blue 3 No. 61,505 and C.I. Disperse Blue 26 No. 63,305.

Sublimable carbinol bases and carbinol base derivatives (particularly ethers) of cationic dyestuffs are also suitable (compare DT-OS (German Published Specifications) 2,323,538, 2,324,017, 2,325,154 and 2,325,155).

In addition, the formulations can contain customary auxiliaries, such as mould preventatives and surface-active agents.

Surface-active agents which can be used are anionic, non-ionic or cationic surface-active agents or mixtures thereof. Examples of anionic surface-active agents which are mentioned are: sulphated alkylene oxide adducts, sulphated partially esterified polyhydric alcohols, alkylsulphonates, sodium dialkylsulphosuccinates, alkylbenzenesulphonates, condensation products of naphthalenesulphonic acids and formaldehyde, ligninsulphonates and oxyligninsulphonates, as well as condensation products of ditolyl ether, formaldehyde and sulphuric acid, or condensation products of m-cresol, 2 naphthol-6-sulphonic acid, formaldehyde and sodium sulphite.

Ethylene oxide adducts and adducts of propylene oxide and ethylene oxide are preferably employed as non-ionic surface-active agents. Ethylene oxide adducts are reaction products of 3 to 60 mols of ethylene oxide and, for example, alkylphenols, long-chain alcohols, long-chain amines or long-chain carboxylic acids, as well as polypropylene glycols. A large proportion of these compounds are described in N. Schönfeldt, Oberflachenaktive Anlagerungsprodukte des Athylenoxids (Surface-active Addition Products of Ethylene Oxide), Wissenschaftliche Verlagsgesellschaft Stuttgart, 1959.Adducts of 10 to 20 mols of ethylene oxide/nonylphenol, phenylethylphenol or benzylhydroxydiphenyl are preferred, as well as, in particular, oxyethylation products, containing 10 to 20 mols of ethylene oxide, of compounds which are obtainable. by subjecting chromates containing phenolic OH groups, or ethers thereof, to a condensation reaction with formaldehyde and amines which contain at least 2 NH groups which are reactive towards formaldehyde, in particular of compounds with the recurring structural unit of the formula

wherein R denotes an alkylene radical which is optionally interrupted by O, S, NR4, CO, arylene or cycloalkylene, or a cycloalkylene radical, R1 and R2 denote hydrogen, alkyl or hydroxyalkyl, R3 denotes hydrogen, alkyl, cycloalkyl, alkoxy, carboxyl ar alkoxycarbonyl and R4 denotes alkyl or hydroxyalkyl.

Compounds of this type are described, for example, in U.S. Patent Specification 3,166,516, U.S. Patent Specification 3,278,637 and DT-OS (German Published Specification) 2,421,606.

Further non-ionic surface-active agents which can be used are, inter alia, fatty acid esters of polyhydric alcohols, such as glycerol, sorbitol, pentaerythritol and glucose and sucrose.

Furthermore, optionally substituted fatty acid amides arid polyamines.

Suitable cationic surface-active agents are long-chain ammonium compounds of the Zephirol type.

The dyestuff dispersions are prepared by wet comminution according to customary processes, for example in a kneader, ball mills, high-speed stirred ball mills, dissolvers, corundum disc mills or rotor-stator mills. They contain 20-65%, preferably 30-50%, of dyestuff, 3-25, preferably 5-15, % of N-hydroxyalkylurea, 1-25%, preferably 5-15%, of surface-active agent and 10-50, preferably 20-40, % of water (the percentages are percentages by weight).

The formulations according to the invention have a good stability towards flocculation, good flow characteristics and, above all, a good water retention power.

In comparison with known additives, to the dyestuff formulation, for preventing drying out the urea compounds added according to the invention have the advantage that they do not increase the viscosity of the formulation.

Example I 1.472 g (14 mols) of diethanolamine are initially introduced into 2,648 g of distilled water.

1,176 g (7 mols) of hexamethylene diisocyanate are added dropwise to this solution, whilst stirring, in such a way that the reaction temperature is kept below 30". After the addition, the mixture is stirred for a further 2 hours at 60"C. A clear, almost colourless 50 per cent strength solution of the addition product is obtained.

Example 2 133 g (1 mol) of diisopropanolamine are initially introduced into 292.3 g of distilled water. 159.3 (0.33 mol) of a biuret-linked triisocyanate formally prepared from 3 mols of hexamethylene diisocyanate by adding 1 mol of water and splitting off 1 mol of CO2, (the commercial product "Desmodur" (Trade Mark) N, BAYER AG) are added dropwise to the solution, whilst stirring, in such a way that the reaction temperature is kept below 30 .

After the addition, the mixture is stirred for a further 2 hours at 600C. A clear, oily solution of the addition product is obtained.

Example 3 61 g (1 mol) of ethanolamine are initially introduced into 118 g of distilled water. 57 g (1 mol) of methyl isocyanate are added dropwise to this solution, whilst stirring, in such a way that the reaction temperature is kept below 30". After the addition, the mixture is stirred for a further 2 hours at 60"C. A clear, colourless, mobile solution of the addition product is obtained.

Example 4 A mixture consisting of a) 50% of the dyestuff Disperse Yellow 54 (C.I. 27,020), b) 8% of the non-ionic surface-active agent of the following structure

wherein x, v and z together denote about 60, c) So of the agent for preventing drying out, obtained in accordance with Example 1, d) 0.6% of commercially available preservatives and e) 36.4% of water is homogenised by stirring and then ground in a continuously operating commercially available stirred mill with grinding bodies, which contains glass beads of 0.3 - 0.5 mm as as the grinding bodies, down to a dyestuff division of less than 5 ,u. A formulation with good flow characteristics is obtained.

Example 5 A mixture consisting of a) 45% of the dry dyestuff of the formula

b) 5% of the non-ionic surface-active agent described in Example 4, c) 0.5% of the anionic dispersing agent of the structure

d) 0.6% of commercially available preservatives, e) 5% of the agent for preventing drying out described in Example 1 and f) 43.9% of water is homogenised by stirring and then ground in a continuously operating commercially available stirred mill with grinding bodies with glass beads of 0.3 to 0.5 mm JZ) until the particle size is less than 5 Il.

Example 6 A mixture consisting of a) 40% of the dry dyestuff of the formula

b) 5% of the non-ionic surface-active agent described in Example 4, c) 0.6% of commercially available preservatives, d) 5% of the agent for preventing drying out described in Example 1 and e) 49.4% of water is homogenised by stirring and then ground in a continuously operating stirred mill with grinding bodies with glass beads of 0.3 - 0.5 mm e, until the particle size is less than 5 .

Example 7 A mixture consisting of a) 50% of the dry dyestuff 1-amino-2-bromo-4hydroxyanthraquinone, b) 10% of the non-ionic surface-active agent described in Example 1, c) 0.6% of commercially available preservatives, d) 5% of the agent for preventing drying out described in Example 1 and e) 34.4% of water is homogenised by stirring and then ground in a continuously operating stirred mill with grinding bodies with glass beads of 0.3 - 0.5 mm P) until the particle size is less than S 1l.

Example 8 A mixture consisting of a) 50% of the dry dyestuff 1-hydroxy-4-ptolylaminoanthraquinone, b) 8% of the non-ionic surface-active agent described in Example 4, c) 0.6% of commercially available preservatives, d) 5% of the agent for preventing drying out described in Example 1 and e) 36.4% of water is homogenised by stirring and then ground in a continuously operating stirred mill with grinding bodies with glass beads of 0.3 - 0.5 mm C3 until the particle size is less than 5 ,u.

The formulations prepared in accordance with Examples 3 - 8 are excellently suitable for the preparation of printing inks for transfer printing.

Example 9 A mixture consisting of a) 40% of the dry dyestuff Pigment Yellow 14 (C.I. 21,095)

b) 12% of a non-ionic surface-active agent prepared by reacting 14 mols of ethylene oxide with 1 mol of a compound which was obtained by reacting hydroxybiphenyl with benzyl chloride, c) 10% of the agent for preventing drying out described in Example 1, d) 0.6% of commercially available preservatives and e) 37.4% of water is processed to a homogenous paste in a dispersion kneader: the dyestuff, surface-active agent and a small proportion of the water are kneaded in the dispersion kneader for 10 minutes so that a temperature of 70"C is reached.

The mixture is then diluted in the kneader with the remaining water, the preservative and the agent for preventing drying out.

Example 10 A mixture consisting of a) 35% of the dry dyestuff Pigment Yellow 17 (C.I. 21,105)

b) 10% of the surface-active agent described in Example 9, c) 10% of the agent for preventing drying out described in Example 1, d) 0.6% of commercially available preservatives and e) 39.4% of water is processed in a dispersion kneader in the manner described in Example 9.

The formulations prepared in accordance with Examples 9 and 10 are excellently suitable for the preparation of printing inks for textile printing.

WHAT WE CLAIM IS: 1. An aqueous formulation of a water-insoluble dyestuff (as hereinbefore defined), comprising a water-soluble N-hydroxyalkylurea of the general formula

in which R denotes an n-valent alkyl cycloalkyl or aryl radical which is optionally substituted and optionally interrupted by hetero-atoms, R1 denotes an alkylene radical having at least two carbon atoms, R2 denotes a hydrogen atom, an alkyl radical or a radical -R1OH and n is 1, 2, 3, 4 or 5.

2. A formulation according to Claim 1, in which the radical R contains a urethane, urea, uretdione, biuret or isocyanuric acid radical.

3. A formulation according to Claim 1, in which the radical R has been derived by removing n isocyanate groups from a corresponding n-valent isocyanate.

4. A formulation according to Claim 1, in which R denotes an n-valent C1 to C6 alkyl radical which is optionally interrupted by urea or biuret groups, a cyclohexyl or cyclopentyl radical which is optionally substituted by methyl groups or a phenyl radical which is optionally substituted by C1 to C4 alkyl, chlorine, bromine, fluorine or C1 to C4 alkoxy, R1 denotes

R2 denotes a hydrogen atom or R1, R3 denotes a hydrogen atom or a methyl group and n is 1, 2 or 3.

5. A formulation according to claim 1, in which the N-hydroxyalkylurea is any of those hereinbefore specifically mentioned.

6. A formulation according to claim 5, in which the N-hydroxyalkylurea is of the formula

7. A formulation according to any of the foregoing claims, in which the water-insoluble dyestuff is a sublimable dyestuff.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. Example 10 A mixture consisting of a) 35% of the dry dyestuff Pigment Yellow 17 (C.I. 21,105) b) 10% of the surface-active agent described in Example 9, c) 10% of the agent for preventing drying out described in Example 1, d) 0.6% of commercially available preservatives and e) 39.4% of water is processed in a dispersion kneader in the manner described in Example 9. The formulations prepared in accordance with Examples 9 and 10 are excellently suitable for the preparation of printing inks for textile printing. WHAT WE CLAIM IS:

1. An aqueous formulation of a water-insoluble dyestuff (as hereinbefore defined), comprising a water-soluble N-hydroxyalkylurea of the general formula

in which R denotes an n-valent alkyl cycloalkyl or aryl radical which is optionally substituted and optionally interrupted by hetero-atoms, R1 denotes an alkylene radical having at least two carbon atoms, R2 denotes a hydrogen atom, an alkyl radical or a radical -R1OH and n is 1, 2, 3, 4 or 5.

2. A formulation according to Claim 1, in which the radical R contains a urethane, urea, uretdione, biuret or isocyanuric acid radical.

3. A formulation according to Claim 1, in which the radical R has been derived by removing n isocyanate groups from a corresponding n-valent isocyanate.

4. A formulation according to Claim 1, in which R denotes an n-valent C1 to C6 alkyl radical which is optionally interrupted by urea or biuret groups, a cyclohexyl or cyclopentyl radical which is optionally substituted by methyl groups or a phenyl radical which is optionally substituted by C1 to C4 alkyl, chlorine, bromine, fluorine or C1 to C4 alkoxy, R1 denotes

R2 denotes a hydrogen atom or R1, R3 denotes a hydrogen atom or a methyl group and n is 1, 2 or 3.

5. A formulation according to claim 1, in which the N-hydroxyalkylurea is any of those hereinbefore specifically mentioned.

6. A formulation according to claim 5, in which the N-hydroxyalkylurea is of the formula

7. A formulation according to any of the foregoing claims, in which the water-insoluble dyestuff is a sublimable dyestuff.

8. A formulation according to claim 1 as hereinbefore specifically described.

9. A printing ink for transfer printing comprising a formulation as claimed in claim 7.