DE2311396A1 - Copper contg. water sol. diazo dyes - for dyeing leather in fast violet shades - Google Patents

Abstract

Title cpds. are of formula (I): (where D is the same or different opt. substd. phenyl or naphthyl gp., Z is -O- or -COO- linked to D in the O-posn. to the azo bridge). They are prepared by converting a cpd. (I) where D' replaces D and OH replaces -O-Cu-Z (whose D' carries H, OH, COOH, SO3H or O-alkyl in the O-posn. to the azo bridge) into the Cu complex.

Description

Copper-containing, water-soluble disazo dyes. The invention relates to dyes of the formula I in which D is identical or different optionally substituted phenyl or naphthyl radicals and Z is a radical of the formula -0- or -COO- bonded to radical D in the ortho position to the azo bridge.

Substituents for the radicals D are, for example, nitro, methyl, methyl, Methoxy, ethoxy, chlorine, bromine, sulfophenylazo or carboxyl and especially hydroxysulfonyl.

Carry the radicals D in order to achieve good solubility, preferably a hydroxysulfonyl group and usually a further substituent.

Of particular technical importance are dyes of the formula Ia, in which the radical D is derived from the following amines: 2-amino-6-nitrophenol-4-sulfonic acid, 2-aminophenol-4-sulfonic acid, 2-aminophenol-4,6-disulfonic acid, 2-amino-6-chlorophenol-4-sulfonic acid, 2-amino-4-chlorophenol-6-sulfonic acid, 2-hydroxy - amino-5-sulfobenzoic acid, 2-amino-4-sulfobenzoic acid, 2-amino-5-sulfobenzoic acid, 1-aminonaphthalene-4-sulfonic acid, 2-aminonaphthalene-6-sulfonic acid, 4-aminoazobenzene -), 4'-disulfonic acid.

To prepare the dyes of the formula I, compounds of the formula II can be used in which the radical D 'in the ortho position to the azo bridge bears a hydrogen atom or an -OH-, -COOH-, -SO3H- or -Oalkyl group, are converted into the corresponding copper complexes.

In this context, alkyl is preferably methyl or xthyl.

The copper plating methods are known in principle and are carried out under analogous to comparable conditions.

The compounds of the formula II are obtained by reacting a diazo compound of amines of the formula D'NH2 with the compound of the formula I-acid imide The coupling takes place in the usual way in a weakly alkaline medium. After the coupling has ended, the dyes formed can be precipitated from the coupling mixture by salting out, separated off and coppered in a further step; in most cases, however, the coppering can be carried out without intermediate isolation of the acid dye.

The copper plating is carried out according to the generally known manufacturing process executed from coppered azo dyes; when -OH- is ortho to the azo group or —CO2H groups, brief heating with the copper-releasing agent is preferably sufficient weakly acidic to weakly alkaline medium, with the o-substituents NOCH5 or -H and -SO5H under the conditions of the dealkylating or the oxidative Coppering worked.

The usual, appropriate means are used as copper-releasing agents water-soluble simple or complex salts of copper with organic or inorganic acids. Mainly there are the water-soluble copper salts of mineral acids or lower fatty acids; suitable are e.g.

Copper (II) sulfate, copper (II) acetate or ammoniacal copper salt solutions. After coppering, the dyes formed can expediently be removed from the reaction mixture excreted and separated by salting out.

The dyes of the formula I are ideal for coloring anything Types of leather. This gives dyeings with excellent fastness properties. Particularly noteworthy is the high color strength of this class of dyes, which are too opaque extensive surface coloring, as well as the very good coloring behavior.

Example 1 23.4 parts of 2-amino-6-nitrophenol-4-sulronic acid become listed in 150 parts by volume of water, mixed with 50 parts of ice and at 150C in Diazotized for 30 to 40 minutes with 22 parts by volume of sodium nitrite solution (5n). Awake 2 hours the excess of nitrous acid is eliminated with sulfamic acid, and after adding 450 parts by volume of water, 23.1 parts of I-acid imide are in the Stirred diazonium solution. After adding a further 200 parts of ice, 15.05 parts are left 50% sodium hydroxide solution flow in and stir for 2 hours. In the well-stirred dye solution 25 parts of vitriol are then dissolved and 8.8 parts of 50% sodium hydroxide solution are added. The solution is heated to 80 ° C, then the dye is made by adding 222 parts Table salt excreted. After cooling to room temperature, the Filter material with 100 parts by volume of 20% saline solution and washed at 800C dried.

The yield is approximately 77 parts of a blue-black dye powder with a salt content of 26%. When coloring on different types of leather Strong navy blue tones with excellent fastness properties are obtained.

The amines mentioned in the table below give analogously the corresponding copper complexes.

Example D-NH2 dyeing on leather 2 2-aminophenol-4-sulfonic acid violet 3 2-aminophenol-4,6-disulfonic acid violet 4 2-amino-6-chlorophenol-4-sulfonic acid purple 5 2-amino-4-chlorophenol-6-sulfonic acid purple 6 2-hydroxy-3-amino-5-sulfobenzoic acid red-violet 7 2-amino-4-sulfobenzoic acid violet 8 2-amino-5-sulfobenzoic acid violet Example 9 22.3 parts of naphthionic acid (1-aminonaphthalene-4-sulfonic acid) are used in 300 parts by volume of water dissolved, neutralized with dilute sodium hydroxide solution, with 21 Parts by volume of sodium nitrite solution (5n) are added and then, while stirring, to a mixture from 100 parts of ice, 100 parts of water and 30 parts by volume of hydrochloric acid (10N). After 2 hours, the excess nitrous acid is eliminated with sulfamic acid. In the diazo solution, after the addition of 200 parts of ice and 300 parts of water, 23.1 g of I-acid imide is stirred, then the mixture is mixed with about 42 parts of sodium hydroxide solution (5n) adjusted to a pH of 8.

After 2 hours, 25 parts of vitriol are in the dye solution dissolved, the pH value is brought to 7 with sodium hydroxide solution, and after heating it up 500C, 100 parts by volume of a 5% hydrogen peroxide solution are added dropwise within one hour to. It is held at 50 ° C. for a further hour and then another 25 parts by volume are added dropwise Add 5 goat hydrogen peroxide solution in about 30 minutes. During the whole During the oxidation period, the pH value is always kept at 7 by adding sodium hydroxide solution.

After 2 hours, filter and add 30 parts of table salt to 100 parts by volume Dye solution deposited the copper complex dye and sucked off at room temperature. The filter material becomes with 100 parts by volume 20 pointer saline solution washed and dried at 800C. About 45 parts of a black one are obtained Dye powder that dyes leather in deep purple tones with very good fastness properties.

Example D-NH2 dyeing on leather 10 2-aminonaphthalene-6-sulfonic acid violet 11 4-Aminoazobenzene-3,4'-disulfonic acid violet

Claims (3)

Claims 1. Copper-containing water-soluble diazo dyes of the formula in which D is identical or different optionally substituted phenyl or naphthyl radicals and Z is a radical of the formula -O- or -COO- bonded to radical D in the ortho position to the azo bridge. 2. Process for the preparation of dyes according to Claim 1, characterized in that compounds of the formula in which the radical D 'in the ortho position to the azo bridge carries a hydrogen atom or an -OH, -COOH, -SO3H- or O-alkyl group, are converted into the copper complexes. 3. Containing dye preparations for dyeing leather in addition to customary constituents of dyestuffs according to claim 1.