HK1026221B - Novel disazo dyestuffs - Google Patents

Description

Novel disazo dyes

The present invention relates to disazo dyes, to a process for their preparation and to their use as fibre-reactive dyes in dyeing and printing processes.

The present invention provides compounds according to formula (I) and salts thereof,

wherein

R₁And R₃Represents hydrogen or a methyl group,

R₂and R₄Represents hydrogen, methyl or methoxy, and

R₅represents hydrogen or C_1-4Alkyl radical

Preferably, naphthyl A has 2 to 3 sulfo groups. In ring B the sulfo groups are attached in the 6, 7, 8 position. Preferably, ring C is substituted with at least one methyl or methoxy group. Specific examples of substituted ring C are benzene residues obtained by coupling with m-toluidine, 2, 5-dimethylaniline, 2-methoxy-5-methyl-aniline, 5-methoxy-2-methylaniline and 3, 6-dimethyl-aniline.

More preferred compounds of formula (I) are represented by formula (Ia),

the compounds of formula (I) may be formed as the free acid or salt form.

When the compound of formula (I) is in the form of a salt, the requirement for a cation attached to the sulfo group is not high provided that the corresponding salt is water soluble, and the cation may be any non-chromophoric cation commonly used in the field of fibre-reactive dyes.

Examples of such cations may be alkali metal cations and unsubstituted ammonium cations, such as lithium, sodium, potassium, ammonium, mono-, di-, tri-and tetramethylammonium, triethylammonium, and mono-, di-and triethanolammonium. Preferred cations are alkali metal cations and ammonium cations, most preferably sodium cations.

The sulphocations in the compounds of formula (I) may be the same or different, for example they may be a mixture of the above mentioned cations, i.e. the compounds of formula (I) may be in the form of mixed salts.

It is another object of the present invention to provide a process for forming compounds of formula (I), their salts or mixtures thereof, which process comprises reacting a compound according to formula (II) with a compound of general formula (III),

wherein R is₁，R₂，R₃，R₄And R₅Having the meaning given above.

The condensation reaction is carried out according to known methods and is preferably carried out at a temperature of 20 to 50 c, more preferably 30 to 40 c and a pH of 4 to 5.

The starting materials are both readily available and can be synthesized from common commercially available starting materials.

The compounds of formula (I) can be isolated in accordance with known methods, for example by salting out with an alkali metal salt by conventional methods, filtration, and optionally drying under vacuum at slightly elevated temperatures.

Depending on the reaction conditions and isolation conditions, the compounds of formula (I) can be formed as free acids or in the form of preferred salts or even in the form of mixed salts containing, for example, one or more of the above-mentioned cations.

The compounds of formula (I) may be converted from the free acid to the salt form or to a mixture of salts and vice versa or the compounds of formula (I) may be converted from one salt form to the other by conventional methods.

The compounds of formula (I), their salts and mixtures thereof are reactive dyes. They are suitable for dyeing and printing substrates containing hydroxyl groups or containing nitrogen. They can produce brown dyeings or prints (prints).

It is a further object of the present invention to provide a process for dyeing or printing hydroxyl-containing or nitrogen-containing substrates, in which the dyeing or printing is carried out with compounds of the formula (I), their salts and mixtures thereof as described above.

Preferred substrates which may be mentioned are leather or fibrous materials which consist of or contain natural or synthetic polyamides and in particular natural or regenerated cellulose such as cotton, viscose or viscose staple fibres. The substrates which are generally preferred are textile materials consisting of or containing cotton.

The compounds of formula (I), their salts or mixtures thereof are used in the form of dyebaths or printing pastes according to all customary dyeing and printing processes in the field of reactive dyeing. Dyeing is preferably effected by exhaustion from an aqueous medium and at a temperature in the range from 30 to 80 ℃, more preferably from 50 to 60 ℃ and a salt content of from 10 to 80g/l, preferably from 10 to 50g/l, more preferably from 10 to 30 g/l. Preferably, the ratio of liquid to article (herein, liquid to substrate) is from 4: 1 to 30: 1, more preferably from 6: 1 to 20: 1.

It is a further object of the present invention to provide the use of the compounds defined above, their salts or mixtures thereof for dyeing or printing substrates as described above.

The compounds according to the invention and their salts have good miscibility with known fibre-reactive dyes. The compounds of the invention, their salts or mixtures thereof can therefore be used as a component in a dyeing or printing process alone or in mixtures of dyeing or printing compositions comprising other reactive dyes of the same type, i.e. the reactive dyes of the process have similar dyeing properties, such as fastness and degree of exhaustion from the dyebath onto the substrate. In particular, the dyes of the present invention can be used in trichromatic dyebaths with certain suitable yellow and blue dyes having the same or other equivalent reactive groups in the appropriate proportions to produce a wide range of hues. The resulting color-matched dyeings or prints have fastness properties which do not differ significantly from those dyeings or prints produced using the individual dyes of the invention.

When used as dyes, the compounds of formula (I), their salts or mixtures thereof provide good exhaustion and fixation rates. In addition, any unfixed dye is easily washed off the substrate. The dyeings and prints formed exhibit good fastness to light and to moisture, such as washing, water, sea water and perspiration. They also exhibit good resistance to oxidizing agents such as chlorinated water, hypochlorite bleach, peroxide bleach and perborate-containing detergents.

The compounds of formula (I), their salts or mixtures thereof can also be used for the preparation of printing inks which are particularly suitable for the inkjet process.

The following examples illustrate the invention. In the examples, all parts and percentages are by weight and all temperatures are in degrees Celsius, unless indicated to the contrary.

Example 1

96 parts of 2-aminonaphthalene-3, 6, 8-trisulfonic acid are placed in 500 parts of water and the pH is adjusted to 0.5 with hydrochloric acid. Under ice-cooling conditions, sodium nitrite was added and a diazonium salt solution was obtained. 56 parts of 2-aminonaphthalene-7-sulfonic acid are added and the pH is maintained between 3 and 4 during the coupling with sodium carbonate solution. After the first coupling reaction was completed, 20 parts of sodium nitrite was added to the resulting solution, which was then added to an ice-water mixture and acidified with 100 parts of 30% hydrochloric acid. After the diazotization reaction was complete, 27 parts of m-toluidine were added for coupling and the pH was kept between 3 and 4 with sodium carbonate solution. After raising the pH to 5-6, 36 parts of 2, 4, 6-trifluoropyrimidine are added and the pH is maintained at this value with sodium carbonate solution at a temperature of 50-60 ℃. At the end of the reaction, the resulting dye is salted out, filtered and dried under vacuum at 50 ℃. In its free acid form, the corresponding formula of the dye is as follows

And the cotton was dyed in a reddish brown color with good moisture resistance. Of particular mention are the lightfastness after irradiation with xenon lamps.

Examples 2 to 30

Table 1 discloses several dyes formed according to a method similar to that described in example 1 and using the corresponding starting materials. In all cases, the resulting dye dyes or prints cotton cloth brown, and the resulting dyeings and prints exhibit good light and moisture resistance, and oxidation stability.

TABLE 1

Application example A

0.3 part of the dye of example 1 is dissolved in 100 parts of demineralized water and 3g of mirabilite (calcined) are added. The dye bath was heated to 50 ℃ and then 100 parts of cotton fabric (bleached) were added. After 30 minutes at 50 ℃, 0.4 parts of sodium carbonate (calcined) was added to the bath. The temperature was maintained at 50 ℃ during the addition of sodium carbonate. The dye bath was then heated to 60 ℃ and further dyed at 60 ℃ for 1 hour. The dyed fabric was then rinsed with running cold water for 3 minutes and then further rinsed with running hot water for 3 minutes. The dye is rinsed in 500 parts of boiling demineralized water with 0.25 parts of olive oil soap for 15 minutes. After rinsing with running hot water (3 minutes) and centrifugation, the dyeings were dried in a drying cabinet at about 70 ℃. The brown cotton dyeings obtained exhibit good fastness properties, in particular a high degree of wet fastness, which are stable to oxidation.

Application example B

10 parts of cotton fabric (bleached) are added to a dye bath containing 100 parts of demineralized water and 3g of mirabilite (calcined). The dyebath was heated to 50 ℃ over 10 minutes and 0.5 part of the dye from example 1 was added. After 30 minutes at 50 ℃, 1 part sodium carbonate (calcined) was added to the bath. The dye bath was then heated to 60 ℃ and dyeing continued for 45 minutes at 60 ℃. The dyed fabric was rinsed with running cold water and then with running hot water and boiled in boiling water according to the method of application example a. The fastness properties of the brown cotton dyeing obtained after rinsing and drying were identical to those shown in application example a.

Cotton was similarly dyed using the dyes of examples 2 to 30 or mixtures of the individual exemplified dyes according to the method described in application example a or B. The cotton dyeing obtained is thus brown and exhibits good fastness properties.

Application example C

Printing paste consisting of the following components is printed on cotton fabric according to a conventional printing method

40 parts of the dye of example 1

100 parts of urea

350 parts of water

500 parts of 4% sodium alginate thickener and

10 parts of sodium bicarbonate

1000 parts are added in total. The printed fabric was dried and fixed in steam at 102-104 c for 4-8 minutes. Following the procedure of application example a, rinsing with cold water and then with hot water, the fabrics were scoured in boiling water and dried. The brown print obtained generally has good fastness properties.

Cotton articles were likewise printed using the dyes from examples 2 to 30 or mixtures of the individual dyes specified in application example C. All prints obtained were brown and showed good fastness properties.

Application example D

3 parts of the dye from example 1 are dissolved at 60 ℃ in 83 parts of demineralized water and 15 parts of diethylene glycol. After cooling to room temperature, a brown printing ink is obtained which, according to the inkjet process, is particularly suitable for printing paper or textile materials composed of cotton.

Similarly, the dyes of examples 2 to 30 or mixtures of the individual dyes exemplified can be used for the preparation of printing inks in accordance with the process given in application example D.

Claims (6)

1. A compound according to formula (I) or a salt thereof,

wherein

R₁And R₃Represents hydrogen or a methyl group,

R₂and R₄Represents hydrogen, methyl or methoxy, and

R₅represents hydrogen or C_1-4An alkyl group.

2. A compound according to claim 1 having formula (Ia),

3. a process for forming compounds of formula (I), their salts or mixtures thereof, which process comprises reacting a compound according to formula (II) with a compound of general formula (III),

wherein R is₁，R₂，R₃，R₄And R₅Having the meaning given in claim 1,

4. a process for dyeing and printing hydroxyl-containing or nitrogen-containing organic substrates, wherein dyeing or printing can be carried out with compounds of the formula (I), their salts or mixtures thereof as described in claim 1.

5. Use of compounds of formula (I), their salts or mixtures thereof according to claim 1 for dyeing or printing textile materials consisting of or containing cotton.

6. Use of compounds of formula (I), their salts or mixtures thereof according to claim 1 for dyeing or printing hydroxyl-group-containing or nitrogen-containing organic substrates or for preparing printing inks suitable for the inkjet process.