DE917991C - Process for the preparation of new trisazo dyes - Google Patents

Description

Process for the production of new trisazo dyes Trisazo dyes, obtained by coupling 1 mole of tetrazodiphenyl in an acidic medium with 1 mole of i-amino - $ - oxynaphthalene-3, 6-disulfonic acid, further coupling in an alkaline medium with 1 mol of diazobenzene and final coupling obtained with m-phenylenediamine or m-tolylenediamine are valuable black nouns Dyes that come as direct deep black, diamond deep black, or oxydiamine black brands are on the market and for dyeing cotton, wool, leather and fibers from regenerated Cellulose can be used.

These dyes, however, have the great deficiency that they always contain technical by-products, which dye acetate silk very yellow-brown. This prevents the dyes from being used for dyeing mixed fabrics, which contain acetate silk effects that should remain undyed or practically white.

It has now been found that azo dyes of a similar structure which do not show this disadvantage can be obtained by using the diazo compounds of amino disazo dyes of the general formula where R and D are aromatic radicals, x is i or 2 and the amino group bonded to D is in the p-position to the azo group, couples with aromatic i, 3-dioxy compounds, which may be partially hydrogenated, and selects the components so that the finished trisazo dyes contain two water-solubilizing but no nitro groups. These dyes dye animal or vegetable fibers deep black, whereas acetate silk does not dye them or it turns them acidic. They can therefore be used for dyeing blended fabrics with acetate silk effects.

Except for dyeing cotton, wool and regenerated fibers Cellulose can also use the new dyes for dyeing leather or synthetic materials Fibers are used.

According to the above general formula, i-amino-8-oxynaphthalene-mono- or -disulfonic acids used, which with 2 moles of diazo components of the specified Composition both acidic and alkaline turn to primary disazo dyes let connect, z. B. i-Amino-8-oxynaphthalene-4-sulfonic acid, i-amino-8-oxynaphthalene-3, 5-disulfonic acid, i-amino-8-oxynaphthalene-3, 6-dis-sulfonic acid, i-amino-8-oxynaphthalene-4, 6-disulfonic acid.

The residues of aromatic diamines (D) are those of 4,4'-diaminodiphenyl, p-phenylenediamine, .4, 4'-diaminostilbene and i, 4-diaminonaphthalene and their substitution products called.

The radicals R are generally those of aromatic amino compounds, mainly those which do not contain any solubilizing groups. In the case, that the: middle component (Aminooxynaphthalinsulfonsäure) only one sulfonic acid group contains, the radical R, which can also be further substituted, should be a Solubilizing group such as SO3H or C O O H contain.

The preparation of the diazo compounds of the amino disazo dyes The above general formula is done in a known manner either by coupling the Tetrazo compound of a diamonds in acidic solution with i-amino-8-oxynaphthalenesulfonic acid, whereupon a monodiazo compound comes into play in an alkaline medium, or you start from the diazo compound of an aromatic amine which is in the p-position carries a nitro or acylamino group to the amino group, it couples this in an acidic medium with an i-amino-8-oxynaphthalenesulfonic acid and then in an alkaline medium with the diazo compound of another monoamino compound which is not a nitro or Contains acylamino group, whereupon the nitro group is reduced or the acylamino group saponified and the amino disazo dye thus obtained is diazotized.

Opposite from the patent specification 711 386, Example 2, has become known weak blue brown trisazo dye of the coloring composition i-amino- The corresponding trisazo dye, obtained by the present process and containing one fewer sulfonic acid group, has a significantly better drawability and the deeper black tone of its colorations. Example i For one of 18.4 kg of 4,4'-diaminodiphenyl, 431 io n-hydrochloric acid and 14 kg of techn. Sodium nitrite tetrazo solution prepared in the usual way is allowed to run a neutral solution of sodium saline of 29.8 kg of i-amino-8-oxynaphthalene-3,6-disulfonic acid at about 10 ° to 12 °. After stirring for several hours at this temperature, about 41.9 of anhydrous sodium acetate is used to blunt it to such an extent that Congo paper is still clearly blued. The mixture is then stirred for 18 to -23 hours at this temperature until the i-amino-8-oxynaphthalene-3,6-disulfonic acid has practically disappeared, cooled to 0 ° with ice, sodium carbonate is added until a neutral or slightly alkaline reaction is obtained then a diazo solution prepared in the usual way from 7.8 kg of aniline is added and a solution of sodium carbonate is run in at 5 to 10 ° until the reaction remains, clearly alkaline. When the diazobenzene has disappeared, an aqueous solution of ii kg of i, 3-dioxybenzene is added. After the dyeing process is finished, it is gently warmed, salted out with about 5 ° J, rock salt and filtered. After drying, a dark, water-soluble powder is obtained which dyes wool, cotton or leather in greenish black shades.

Compared to known dyes, the end components i, 3-diaminobenzene or contain 2,4-diaminoi-methylbenzene, the new dye provides essential purer silk acetate effects.

Instead of aminobenzene, other aromatic amines can be used which do not contain sulfonic acid groups, thereby reducing the hue to a certain extent Extent can be influenced. For example, the dyes from i-amino-2-chlorobenzene, i-Amino-4-chlorobenzene, 2, 4- or 2, 5-dichloro-i-amirlobenzene reddish shades of black. Example 2 If the i, 3-dioxybenzene in Example i is replaced by 12.6 parts 1, 3, 5-trioxybenzene, a dark powder is obtained after separation and drying, the animal and vegetable fiber colors in blue-black tones while it Acetate silk leaves practically undyed.

Instead of 1, 3, 5-trioxybenzene, for example 1, 2, 3-trioxybenzene, i, 3-Dioxynaphthalene, dihydroresorcinol can be used, green or red tinged receives black dyes of similar properties. Example 3 1q., 7 kg of i-amino-4-nitrobenzene are diazotized in the usual way. The diazo solution is cooled with ice Congo acid reaction with a weakly acidic solution of 3,9 kg of i-amino-8-oxynaphthalene-3, 6-disulfonic acid combined. As soon as the i-amino-8-oxynaphthalene-3, 6-disulfonic acid has disappeared, a concentrated solution of about 6.5 kg of sodium carbonate is left flow in and add a diazo solution prepared in the usual way from 9.5 kg of aniline added. Finally, a solution of about 18 kg of sodium carbonate is allowed to flow in, until a clearly alkaline reaction is present, and stir for 2 hours at 0 °.

For the purpose of reducing the nitro group, one sets after neutralization with about 141 io n hydrochloric acid one Solution of 42 kg of crystalline Sulfur sodium added, stirred for 1 to 2 hours at about 20 to 25 ° until solution has occurred, filtered if necessary from impurities and precipitates with rock salt. One filtered and washes with salt water.

The amino disazo dye is dissolved in water. To this you add 7 kg Add sodium nitrite and run the mixture in ice and hydrochloric acid. The diazodisazo compound is then combined with a weakly alkaline solution of ii kg of 1,3-dioxybenzene, with soda, sodium acetate or sodium bicarbonate serving as acid-binding agents can. After separating and drying, a dark dye powder is obtained, which dyes animal and especially vegetable fibers black, whereas acetate silk leaves uncolored.

A black dye with similar properties is obtained if the aniline is replaced by the equivalent amount of a-naphthylamine.

Claims (1)

PATENT CLAIM: Process for the preparation of new trisazo dyes, characterized in that the diazo compounds of amino disazo dyes of the general formula where R and D are aromatic radicals, x is i or 2 and the amino group bonded to D is in the p-position to the azo group, couples with aromatic i, 3-dioxy compounds, which may be partially hydrogenated, and selects the components so that the finished trisazo dyes contain two water-solubilizing but no nitro groups. Referred publications German patent specifications 711 386, 66 351.