GB2150583A

GB2150583A - Monoazo dye mixtures

Info

Publication number: GB2150583A
Application number: GB08429929A
Authority: GB
Inventors: Peter Liechti
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1983-12-02
Filing date: 1984-11-27
Publication date: 1985-07-03
Also published as: DE3443621A1; GB8429929D0; JPS60135460A; GB2150583B; FR2555997A1; FR2555997B1; CH654589A5

Abstract

Mixtures of at least two different disperse dyes of the formula <IMAGE> wherein R1 and R2 are each C3-C8-alkyl and R3 is C1-C2-alkyl, the number of alkyl-C atoms of R1, R2 and R3 per dye molecule together being at least 7 and at most 14, are distinguished by a good pH- stability and very good build-up properties and substantivity; they are particularly good for dyeing polyester fibres.

Description

SPECIFICATION Dye mixtures The invention relates to novel dye mixtures, to processes for producing them, and to their use for dyeing and printing textile materials.

Dyes of the formula

(wherein X and Y independently of one another are each alkyl, and Z is methyl or ethyl) are known. Thus, for example, the dye wherein X = Y = ethyl and Z = methyl is a dye which is often met with in practice but which, however, is very rapidly decomposed at pH values of the dye bath above 5 and is therefore of no significance in exhaust dyeing. It is thus used almost exclusively in continuous dyeing. When X and Y are extended to propyl, the dye indeed still exhausts weli and exhibits good build-up properties, But its pH-stability is not sufficiently improved. Not until X and Y = butyl does the pH-stability meet the requirements of exhaust dyeing; this dye however exhausts badly and exhibits inadequate build-up properties.

It has now been found that mixtures of the said dyes, in particular of the dipropyl due with the dibutyl dye, surprisingly exhibit a very good pH-stability and also very good build-up properties and very good substantivity.

The invention accordingly relates to a dye mixture containing at least two dyes which correspond to the formula I

wherein R, and R2 independently of one another are each a cC3-C8-alkyí group, and R3 is a C,-C2-alkyl group, the number of alkyl-C atoms of R1 and R2 and R3 per dye molecule together being at least 7 and at most 14, especially 7 to 11.

Preferred dye mixtures contain two dyes of the formula I in the ratio of 30-70% by weight of the one dye to 70-30% by weight of the other dye; it is in particular a 50: 50% by weight ratio.

When R, and R2 independently of one another are each C3-C8-alkyl, it is straight-chain or branched-chain alkyl, for example n-propyl, iso-propyl, n-butyl, sec-butyl, i-butyl, n-hexyl, n-octyl and 2-ethylhexyl. The two groups R, and R2 can be identical or different from one another.

Preferred dye mixtures contain the dyes of the formulae

or the dyes of the formulae

wherein R3 in each case has the meaning defined.

The dye mixtures according to the invention can be produced by various methods, for example: a) by mixing together two or more dyes of the formula I which differ from one another; b) by melting together two or more dyes of the formula I which differ from one another; or c) by diazotising a diazo component of the formula

and coupling the diazotised product to a mixture of two or more coupling components differing from one another and corresponding to the formula

wherein R1, R2 and R3 have the meanings defined, and reacting the mixture of the coupling products of the formula

with metallic cyanide in a polar, optionally aqueous, organic solvent to obtain a mixture-of the dyes of the formula I.

When the process variant a) is used, the dye mixture according to the invention is produced by mixing together in the dry or wet state the individual dyes of the formula I at room temperature. To this mixture are advantageously added dispersing agents, particularly those of anionic or nonionic nature, and water, and the mixture is ground with the aid of grinding elements (for example glass balls) into the form of a ready-for-use dispersion.

Anionic dispersing agents suitable for the said purpose are for example condensation products of naphthalenesulfonic acids and formaldehyde, especially dinaphthylmethanedisulfonates or modified lignin sulfonates.

Examples of known and particularly suitable nonionic dispersing agents are addition products of about 3 to 40 mols of ethylene oxide with alkylphenols, fatty alcohols and fatty amines.

When the stated variant b) is used for producing the dye mixture according to the invention, the dyes in this case melted together to form a homogeneous melt; this is subsequently allowed to cool, and is then ground, optionally with an anionic or nonionic dispersing agent and water, in the presence of grinding elements; and by this variant too is obtained a ready-for-use dispersion.

Finally, in the case of process variant c), the starting products of the formulae II and Ill are known, and can be produced by known methods. Thus, for example, the coupling components of the formula Ill are obtained by reacting the corresponding acetamidoanilines of the formula

with alkyl halides of the formula R1-Hal or R2-Hal or with alkyl sulfates of the formula R,-O-SO3 or R2-O-SO30H, in the presence of acid acceptors, for example alkali carbonates, especially sodium carbonate.

The coupling reaction of the mixture of the coupling components of the formula Ill with the diazo component of the formula II is performed in a known manner, a coupling product mixture of the formula IV being obtained, which can then be isolated. In this mixture, the halogen atom in the diazo component is subsequently replaced by the cyano group: this is effected by reacting the coupling product mixture of the formula IV with metallic cyanides. This reaction, which is preferably carried out with copper cyanide, is preferably performed in a polar, optionally aqueous solvent, such as dimethyl sulfoxide, dimethylformamide. N-methylpyrrolidone or pyridine/water mixtures, at a temperature of about 40 to 1 50 C, preferably 80 to 1 30 C. A mixture of dyes of the formula I is obtained by this method.

A further analogous possibility for producing dye mixtures of the formula I consists of diazotising a diazo component of the formula V

reacting the diazotised product with a mixture of coupling components of the formula Ill to give a coupling product mixture of the formula

and exchanging the halogen atom in the diazo component for a nitro group by means of alkali nitrite and copper salts.

The novel dye mixtures of the formula I are used for dyeing and printing materials, particularly textile materials, which are dyeable with disperse dyes. Before being used, the dye mixtures are advantageously converted, if this has not been done during production, into dye preparations. For this purpose, the mixtures can be ground to bring their mean particle size down to between 0.01 and 10 pm. Grinding can be carried out in the presence of dispersing agents. For example, the dried dye mixture is ground together with a dispersing agent, or is kneaded in paste form with a dispersing agent, and thereupon dried in vacuo or by spray drying.With the preparations thus obtained it is possible, after the addition of water, to dye, pad or print in a long liquor (ratio of goods to liquor greater than 1:5) or in a short liquor (ratio of goods to liquor 1:1 to 1:5).

From an aqueous suspension or dispersion, the novel dye mixtures have excellent affinity for shaped articles made from fully-synthetic or semi-synthetic materials of high molecular weight.

They are particularly suitable for dyeing, padding or printing fibres, filaments or fleeces, fabrics or knitted goods made from linear aromatic polyesters, as well as from cellulose-2 1 /2-acetate and cellulose triacetate. Also synthetic polyamides, polyolefins, acrylonitrile polymerisation products and polyvinyl compounds can be dyed and printed with the novel dye mixtures.

Particularly valuable dyeings are obtained on linear aromatic polyesters. These are in general polycondensation products of terephthalic acid and glycols, especially ethylene glycol, or polycondensation products of terephthalic acid and 1 ,4-bis-(hydromethyl)-hexahydrobenzene.

The polyester fibres are dyed, by processes known per se, in the presence of carriers at temperatures of between about 80 and 1 25 C, or in the absence of carriers under pressure at about 100 to 140 "C, by the exhaust process. Furthermore, these fibres can be padded or printed with the aqueous dispersions of the dye mixtures, and the resulting impregnating fixed at about 140 to 230"C, for example by means of steam, contact heat or hot air. Cellulose-2 1 /2-acetate is dyed preferably between about 65 and 85"C, and cellulose triacetate at temperatures up to 11 5 C.

There are usually added the already mentioned customary dispersing agents, which are preferably anionic or nonionic, and which can be used also in admixture with one another.

The customary thickening agents are used for padding and printing, for example modified or unmodified natural products, for example alginates, British gum, gum arabic, crystal gum, locust bean flour, tragacanth, carboxymethylcellulose, hydroxyethylcellulose, starches or synthetic products, for example polyacrylamides or polyvinyl alcohols.

The dyeings obtained have good fastness properties; to be especially emphasised is their capability of being able to be mixed with any dyes, particularly with yellow dyes, and of not exhibiting "catalytic fading"; and also to be emphasised is their good pH-stability, in particular in the exhaust process, and their very good and uniform substantivity.

The Examples which follow further illustrate the invention without the scope thereof being limited by them. Except where otherise stated, 'parts' are parts by weight.

Example 1: 2.5 parts of the dye of the formula

and 2.5 parts of the dye of the formula

are mixed together, and the mixture is ground with 10 parts of a low-salt dispersing agent (dinaphthylmethanesulfonic acid type) in 85 parts of water, with the aid of 300 parts of glass balls of 0.5 mm diameter, in a Mikrosol mill. The resulting dispersion containing a dye mixture can be used for dyeing polyester materials.

The dyes of the above formulae are obtained as follows: 8.6 parts (about 0.033 mol) of 3dibutylaminoacetanilide (produced by 8 hours' heating, at the reflux temperature, of 3aminoacetanilide with excess butyl bromide in the presence of sodium carbonate) are dissolved in 300 parts of 50% aqueous acetic acid, and to the solution is then added dropwise, within 2 hours, a diazonium salt solution produced from 5.1 parts of 40% nitrosylsulfuric acid in 12 parts of 96% sulfuric acid and 7.9 parts (0.03 mol) of 2,4-dinitro-6-bromoaniline. The precipitated dye of the formula

is filtered off under suction, washed with water and then with methanol and dried. There are obtained 1 3.7 parts (85.3% of theory) of dark blue powder, m.p. 195 to 1 97 C.

10.7 parts (0.02 mol) thereof are dissolved in 95 parts of pyridine, and to the solution are added 1.9 parts of copper-l-cyanide and 55 parts of water; the mixture is subsequently stirred for 10 hours at 60-70"C, the precipitated dye is filtered off at 50"C with suction, washed with a warm pyridine/water mixture at 50"C, then with water and dried. There is thus obtained the dye of the formula

in the form of greenish-brown powder, m.p. 1 96 to 1 98 C; yeild 6.6 parts (~69% of theory).

In an analogous manner is obtained the dye of the formula

m.p. 192-194"C.

Example 2: A dispersion similar to that described in Example 1 is obtained by melting together the two dyes according to Example 1 (m.p. 1 72 to 1 74 C) in the ratio of 1 :1, and then grinding the cooled melt to obtain a dispersion.

Example 3: The dye mixture containing the dyes of the formulae

in the ratio of about 50: 50% by weight is obtained by coupling equimolar amounts of the two coupling components of the formulae

with a diazotised diazo component of the formula

and reacting the mixture obtained to the corresponding cyano derivative in the manner described in Example 1.

Example 4: When 7 parts of the dye of the formula

are melted with 3 parts of the dye of the formula

there is obtained a dye mixture having a melting point of 183 to 186"C.

Example 5: A dye mixture containing the dyes of the formulae

is obtained by coupling the acetylaminoanilides, obtained by mixed alkylation with equimolar amounts of n-propylbromide and n-butylbromide, with diazotised dinitrobromoaniline, and converting the resulting mixture into a mixture with the corresponding cyano compounds.

Example 6: 4000 parts of polyester fabric (Diolen) are dyed, for one hour at 1 30'C, in 100,000 parts of a dye bath containing 1 92 parts of the dispersion according to Example 1 (corresponding to 9.6 parts of mixed dye) and 50 parts each of a wetting agent (for example fatty acid methyl tauride) and of a dispersing agent (for example based on dinaphthylmethane sulfonate).

There is obtained an intense blue dyeing having very good fastness to light. The dye bath is completely exhausted.

When there are used, in place of the dye mixture, 9.6 parts of the respective individual dyes, the exhaustion of the bath is considerably poorer, and in the case of the dibutyl compound the dyeing is less deep.

Example 7: When dyeings according to Example 6 are carried out but with the difference that the dyeings are buffered at pH 4, 5, 6, 7 and 8, a slight change of shade is firstly observed at pH 6, and a weaker dyeing not until pH 7, whereas a comparative dyeing containing the individual dyeing of the formula

becomes clearly weaker even at pH 5.

Claims

1. A dye mixture containing at least two dyes which correspond to the formula I

wherein Rl and R2 independently of one another are each a C3-C,,-alkyl group, and R3 is a C,-C2-alkyl group, the number of alkyl-C atoms of R, and R2 and R3 per dye molecule together being at least 7 and at most 14.

2. A dye mixture according to claim 1, which contains two dyes of the formula

3. A dye mixture according to claim 2, which contains the two dyes in the ratio of 30-70% by weight of the one dye to 70-30% by weight of the other dye.

4. A dye mixture according to claim 3, which contains the two dyes in the ratio of 50% by weight of the one dye to 50% by weight of the other dye.

5. A dye mixture according to claim 2, which contains the dyes of the formulae

wherein R3 has the meaning defined in claim 1.

6. A dye mixture according to claim 1, which contains the dyes of the formulae

wherein Rs has the meaning defined in claim 1.

7. A process for producing a dye mixture according to claim 1, which process comprises a) mixing together two or more dyes of the formula I which differ from one another; b) melting together two or more dyes of the formula I which differ from one another; or c) diazotising a diazo component of the formula

and coupling the diazotised product to a mixture of two or more coupling components different from each other of the formula

wherein R1, R2 and R3 have the meanings defined under the formula I in claim 1, and reacting the mixture of the coupling products of the formula

with metallic cyanide in a polar, optionally aqueous, organic solvent to obtain a mixture of the dyes of the formula I according to claim 1.

8. The use of a dye mixture according to claim 1, or of a dye mixture obtained by one of the processes according to claim 7, for dyeing and printing textile materials.

9. The use according to claim 8 for dyeing and printing polyester materials in the exhaust process.

10. The textile materials dyed and printed according to claims 8 and 9.

11. A dye mixture according to claim 1 substantially as described with reference to any of Examples 1 to 5.

1 2. Process for producing a dye mixture according to claim 7 substantially as described with reference to any of Examples 1 to 5.

1 3. The use of a dye mixture according to claim 1 for dyeing and printing textile material substantially as described with reference to Examples 6 or 7.