DE485567C - - Google Patents

Description

It has been shown that blue-gray to violet and black vat dyes from benzanthrone sulfonic acids, Their methyl or halogen derivatives can be prepared by treating them with hydroxylamine and the resulting Product heated with alkalis. If necessary, the sulfonation of the benzanthrones and the subsequent hydroxylamine treatment without separation of the benzanthrone sulfonic acid are carried out, so that there is a saving due to reduced consumption of sulfuric acid results.

The alkaline melt can be mixed with alcoholic potassium hydroxide or with molten sodium or potassium hydrox3'd be carried out.

The following examples illustrate good methods according to the invention without affecting the Protection should be limited to it.

. .

example 1

16.8 parts of benzanthrone sulfonic acid are dissolved in 280 parts of sulfuric acid of 66 ° Be while stirring, 17.5 parts of iron sulfate crystals are added and, after cooling, are gradually adding 7 parts of hydroxylamine hydrochloride. The mixture is heated with stirring to 150 ° and holds at 150 ° C for two hours the cooling is poured into 1120 parts of ice and water. The mixture is stirred for several hours filtered, washed the residue with 20 percent brine and dried. That on this Well-obtained intermediate is a reddish brown powder in the form of its sodium salt. It dissolves in concentrated sulfuric acid to form a yellowish-orange solution of the sulfate, wel- ' ches has a green fluorescence. In dilute sulfuric acid it is soluble to a yellowish-orange solution, which through Adding alkali turns reddish brown.

10 parts of the product gradually becomes 100 parts of stirred molten potassium hydroxide added at 180 ° C. The temperature is gradually increased to 240 °, with one considerable foaming and ammonia development occurs. The mixture then becomes a Obtained for an hour at 240 ° and then cooled and extracted with 2000 parts of water. The whole is then heated, bubbled with air and filtered, and the residue becomes Washed out with dilute sodium hydroxide solution. It is then boiled with dilute hydrochloric acid, filtered, the residue washed with water, allowed to drain and dried. The product dyes cotton from blue-gray to blue-black.

Example 2

30 parts benzanthrone be stirred at 98 to 100 ⁰ C and 210 parts of 7prozentigem oleum has occurred until a complete sulfonation. This is indicated by the fact that a sample is completely soluble in water. The mixture is then diluted with 10 parts of water and 580 parts of sulfuric acid at 66 ° Be and stirred. 48 parts of iron sulfate crystals are added, the whole is cooled and then 20 parts of hydroxylamine hydrochloride are gradually added. The mixture is then heated under stirring to 150 ⁰ C and obtained at 150 ° C for two hours, then cooled and poured into 4200 parts of ice and water. 100 parts of salt are then added and the mixture is stirred for several hours, filtered, and the residue is washed out with 2 percent brine and dried.

10 parts of the product gradually becomes 100 parts of stirred molten potassium hydroxide added at 180 ° C. The temperature is gradually increased to 240 ° C, whereby considerable foam formation and development occurs. The mixture is then one hour obtained long at 240 ° C, then cooled and extracted with 2000 parts of water. The whole is heated, oxidized with air, filtered and the residue washed out with dilute sodium hydroxide solution. It is then boiled with dilute hydrochloric acid, filtered and the residue washed with water, allowed to drain and dried. The product dyes cotton from bluish gray to bluish black.

Instead of the 30 parts of benzanthrone, 31.8 parts of methylbenzanthrone can have a temperature of 197 to 199 ° C can be used, which is made from 2-methylbenzanthrone. You get a similar one Dye. Instead of '' hydroxylamine can be a solution of hydroxylamine, which obtained by electrolytic reduction of nitric acid can be applied.

Example 3

23 parts of Bz 1 · chlorobenzanthrone
formula

with the

be stirred at 15 to 20 ⁰ C with 24Ö parts of 7prozentigern oleum until the solubility in water of a sample indicates that a complete sulfonation has occurred. 152 parts of sulfuric acid (96%) and then 12 parts of water are added and the whole is cooled in a water bath. 24 parts of finely ground iron sulfate crystals are then gradually added, followed by 13.2 parts of hydroxylamine hydrochloride. The mixture is then heated and maintained at 145 to 150 ^° C. for two hours. After cooling, the reaction mixture is poured into 800 parts of ice and 800 parts of water, stirred, mixed with 200 parts of salt, stirred again and filtered. The residue is washed acid-free with 2 percent saline solution and dried. (During the wash, the color changes from yellow-brown to chocolate-colored.) Yield equals 60.5 parts.

60 parts of powdered potassium hydroxide and 30 parts of absolute alcohol are added with stirring for half an hour at 150 to 155 ° C heated. The temperature then increases to 170 ° C increased, with 10 ecm of alcohol being distilled off at the same time. 18.2 parts of the 60.5 Portions of the intermediate are now added and the temperature becomes one hour maintained at 170 to 175 ° C for a long time, then within half an hour increased to 230 ° C and maintained at 230 to 240 ° C for two hours. After cooling, the melt is extracted with water, boiled and passed through oxidized by a stream of air. It is then filtered and the residue with alkali-free washed out in hot water and dried. Yield equal to 6.0 parts.

With caustic soda and sodium hydrosulfite you get a blue colored vat, which Cotton dyes purple after oxidation.

Example 4

ι part of a paste (10%), which is made of a dye produced according to any of the preceding embodiments, is reduced by being stirred with 5 parts of water, 8.5 parts of sodium hydroxide 76 ⁰ Tw. and 1.5 parts of sodium hydrosulfite. This mixture is added to 1250 parts of water at 60 ° C. 50 parts of cotton are added to the vat produced in this way and the mixture is ^{worked through at 60 °} C. for half an hour. The cotton is rinsed, the dye is oxidized in the air, acidified, rinsed, soaped and dried.

The sulfonated benzanthrone used as starting material dissolves in concentrated form Sulfuric acid with a yellow-brown color, which shows a strong green fluorescence. The solution in hot water there is no change in color due to the addition of alkali. When melting with Alkali gives you a product which is in concentrated sulfuric acid with a purple color dissolves.

The sulfonated chlorobenzanthrone, which as

The starting material is soluble in concentrated sulfuric acid with a red-orange color. This solution shows yellow fluorescence. The aqueous solution hardly shows any color change on the addition of alkali. When melting with alkali, a product is obtained which in concentrated sulfuric acid is soluble with a gray-green color.

Claims (1)

Claim: Process for the production of vat dyes of the benzanthrone series, thereby characterized in that sulfonated benzanthrones are condensed with hydroxylamine and the product with alkalis, advantageous alcoholic potassium hydroxide solution, heated.