DE1040719B - Process for the preparation of trisazo dyes - Google Patents

Description

Process for the preparation of trisazo dyes It has been found that new trisazo dyes are obtained by using diazodisazo compounds of the general formula (where R is a radical from the benzene or naphthalene series, XI, X2 is hydrogen, the methyl or methoxy group and Z is an acid radical) with 2,3-dioxynaphthalene-6-sulfonic acid.

The diazodisazo compounds are prepared in the following way: A tetrazotized 4,4'-diaminodiphenyl is first in mineral acid solution with a 1-amino-8-oxynaphthalene-disulfonic acid coupled and then in alkaline solution reacted with a diazotized amine of the benzene or naphthalene series.

The coupling of the diazodisazo compounds thus obtained with 2,3-dioxynaphthalene-6-sulfonic acid takes place in an alkaline medium.

The trisazo dyes obtainable by the present process color in lively blue to reddish blue shades and are excellent for dyeing leather, especially suede. The dyes are very good soluble in water and stain well through. The dyeings obtained have good lightfastness and good waterfastness in which they are advantageously more similar to known dyes Composition differ.

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

Example 1 18.4 parts of 4,4'-diaminodiphenyl are tetrazotized and coupled with 31.9 parts of 1-amino-8-oxynaphthalene-3,6-disulfonic acid with mineral acid. An aminobenzene prepared from 9.3 parts of aminobenzene is added to the resulting intermediate Diazo solution and couples in the presence of sodium carbonate. The resulting diazodisazo compound is with a solution of 24.0 parts of 2,3-dioxynaphthalene-6-sulfonic acid in the presence implemented by sodium carbonate. When the coupling is complete, it is deposited and dried. A dark, water-soluble powder is obtained, the leather with a slightly red emulsion Colors blue.

If 14.3 parts of 1-aminonaphthalene are used instead of aminobenzene, this is how you get similar blue dyes. If 1-amino-8-oxynaphthalene-3,6-disulfonic acid is used instead 1-amino-8-oxynaphthalene-4,6-disulfonic acid is obtained as an intermediate component purple-tinged blue coloring products.

Example 2 18.4 parts of 4,4'-diaminodiphenyl are tetrazotized and coupled with 31.9 parts of 1-amino-8-oxynaphthalene-3,6-disulfonic acid with mineral acid. A slurry of the diazo compound is added to the intermediate product, which was prepared from 17.3 parts of 1-aminobenzene-4-sulfonic acid, and couples in Presence of sodium carbonate. The resulting diazodisazo compound is with a Solution of 24.0 parts of 2,3-dioxynaphthalene-6-sulfonic acid in the presence of sodium carbonate implemented. After depositing and drying, a dark powder is obtained that consists of Aqueous solution dyes leather a red-embroidered blue.

If, instead of 1-aminobenzene-4-sulfonic acid, other arylamine sulfonic acids are used, such as 2-chloro-1-aminobenzene-4-sulfonic acid, 2-chloro-6-methyl-l-aminobenzene-4-sulfonic acid, 1-aminobenzene-2,4-disulfonic acid or 1-aminobenzene-2,5-disulfonic acid, so gets one blue dyes of similar properties. If you take the example 1 and 2 instead of 4,4'-diaminodiphenyl as tetrazo components 4,4'-diamino-3,3'-dimethoxydiphenyl or 4,4'-diamino-3,3'-dimethyldiphenyl, so will also be blue coloring dyes obtain.

Claims (1)

PATENT CLAIM: Process for the production of trisazo dyes by coupling diazodisazo compounds of the general formula (where R is a radical from the benzene or naphthalene series, X1, X, hydrogen, the methyl or methoxy group and Z is an acid radical) with oxynaphthalene sulfonic acids, characterized in that the azo component used is 2,3-dioxynaphthalene-6-sulfonic acid. Considered publications: German Patent Specifications No. 153 557, 917 633; U.S. Patent No. 583,635. When the application was made public, a staining table and explanation were provided.