DE836385C - Process for the preparation of acidic anthraquinone dyes - Google Patents

Description

Process for the preparation of acidic anthraquinone dyes It has been found that acidic anthraquinone dyes which are reddish blue are obtained when anthraquinone derivatives of the following general formula are obtained wherein X and Y are alkyl radicals and the arylamino radical can be further substituted, allowing halogenating agents to act. The new dyes dye wool, silk, super polyamide fibers and other textiles in very lively reddish-blue tones with excellent properties such as washfastness, milled fastness and lightfastness. The dyes are also distinguished by their good drawability from a neutral bath.

For halogenation suitable starting materials are, for example: i-Amin0-4- (2'6'-dimethyl) -phenylaminoanthrachinon-2-SU1fonsäure, i-Amin0-4- (2'4'6'-trimethyl) - phenylaminoanthrachinon - 2 - sulfonic acid , i - amino - 4 - (2'4'- dimethyl - 6'-ethyl) - phenylamino-2--antlirachinon sulfoiisäure etc. Instead of the free sulfonic acids can also their alkali metal salts are used. The process is preferably carried out in conc. Sulfuric acid, sulfuric acid monohydrate or in dilute oleum in the presence or absence of halogen carriers such as iodine, iron salts, etc. at temperatures from 0 to 40 ', at the end of which the temperature can be increased to 40 to 8o'. Example i 20 parts of i-amino-4- (2'4'6'-trimethyl) -phenylaminoanthraquinOn-2-sulfonic acid sodium are dissolved in 12o parts of sulfuric acid monohydrate at 10 to 25 '. Then 6.9 parts of bromine are slowly run in with thorough stirring at from 0 to 30 ', preferably from 10 to 20'. After 10 to 14 hours, the temperature is increased to 6o 'for 3 hours, whereupon the reaction mass is poured onto ice and water. The precipitated dye is filtered off, stirred in 30% sodium chloride solution, neutralized, filtered again and dried. The dye thus obtained, a thank-you blue powder, dyes wool in very vivid reddish-blue shades with excellent fastness properties.

If you take i-amin0-4- (2'4'6'-triniethyl) - phenylaminoanthraquinone - 2 - sulfonic acid sodium, a corresponding amount of i-amino-4 - (2'6'-dimethyl - 4'-methoxy ) - phenylaminoanthra -quinone-2-sulfonic acid sodium, you get a greener dye with similar properties. EXAMPLE 2 18.8 parts of i - amino - 4 - (2'4'6'-trimethyl) - phenyl -aminoaiithraquinone-2-sulfonic acid are dissolved in 20 parts of oleum of 20%, at 10 to 20 ', with stirring. At 0 to 10 ', 7.5 parts of bromine are added dropwise and the mixture is left to stir at 10 to 20' until the reaction has ended. The dye formed is deposited by pouring it into water or ice and is identical to that of Example i. Instead of oleum, Sch #% - eic acid monohydrate can also be used.

If, instead of i-amin0-4- (2'4'6'-trimethyl) -plieii #, laminoanthraquinone-2-sulfonic acid, the equivalent amount of i-amin0-4- (2'4'-diethyl-6'- Methyl) -phenylamijioanthrachinon-2-sulfonic use, one obtains a similar dye.

Example 3 14.6 parts of i-amin0-4- (2'6'-dimethyl) -phenylaminianihi-aquinone-2-sulfonic acid are dissolved in 130 parts of sulfuric acid from 95 to 100%, at 10 to 20 '-, t and 6 parts of bromine are slowly added with thorough stirring. The mixture is stirred until the reaction has ended, and at the end the temperature can be increased to 40 to 6o '. The dye formed is separated off in the customary manner by pouring it into ice and water and filtered off. After working up and drying, a dark blue powder is obtained which dyes wool, silk and other textiles in very vivid reddish blue shades with excellent fastness properties. Example 4 2o parts of i-amino-4- (2'4'6'-trimethyl) -phenylaminoanthraquinone-2-sulfonic acid sodium are dissolved in 12o parts of oleum from 3 to 40 /, with thorough stirring at 10% 20 ', whereupon 0.2 parts of iodine are added. 3.4 parts of chlorine are then slowly passed in. After the reaction has ended, it is worked up in a known manner. The dye obtained dyes wool in very vivid, genuine reddish-blue tones.

Instead of oleum, sulfuric acid from 95 to 100% can be used and finally heated to 40 to 70 ° for a few hours in order to terminate the reaction more quickly.

If instead of i-amin0-4- (2'4'6'-thimethyl) -phenylaminoanthraquinone - 2 - sulfonic acid sodium a corresponding amount of i-amin0-4- (2'6'-dimethyl) - phenylaminoanthraquinone - 2 - If sodium sulfonic acid is used, a similar dye is obtained which dyes wool in somewhat redder tones.

Claims (1)

PATENT CLAIM: Process for the production of acidic anthraquinone dyes, characterized in that anthraquinone derivatives of the following general formula are used wherein X and Y are alkyl radicals and the arylamino radical can be further substituted, allowing halogenating agents to act.