SU64034A1 - The method of obtaining diazoamino compounds - Google Patents

Description

Mixtures of diazoalgino compounds with naphthol type AU are widely used to obtain ice azo dyes on the fiber and are known by the name Rapidogenic dyes.

The diazo amino compound (triazenes) is obtained by reacting an aqueous solution of a diazonium salt with a primary or secondary fatty or aromatic amine (stabilizer). In order to obtain these compounds, any suitable aromatic amines are diazotized in an aqueous solution, which do not have solubility groups, and the diazonium salt solution is sutured into a stabilizer solution.

Diazoamino compounds prepared according to the German patents 513209, 535670, 5507I, 552283, which describe the use of stabilizers with groups that give the triazene molecule a good solubility, are practically valuable for obtaining fiber-insoluble azo dyes.

The synthesis of triazenes is carried out in a neutral or acetic acid medium, and has a number of disadvantages, of which the most significant for production are the following;

1. The diazoamino compound is well dissolved in water, therefore. they are obtained in possibly more concentrated solutions. The conduct of the processes of diazotization and the formation of triazenes in concentrated solutions is associated with a number of unsuitable side processes and with the contamination of the final product with inorganic salts formed during the neutralization of excess acid. In view of the foregoing, the diazo amino compounds are not sufficiently concentrated and, moreover, require special purification.

2. In the preparation of diazo amino compounds, the mineral acid, taken for diazotization, should be neutralized. To use caustic alkalis for this purpose because of the possible formation of isodiazoates, carbonic acids and alkalis cause strong foaming, which makes it difficult to carry out the production process. Most patents recommend the use of sodium acetate, but the process

the formation of triazenes in acetic acid is reversed, and in order to shift the equilibrium in the desired direction towards the end of the process, it is not possible to avoid the addition of a neutralizing agent.

3. Slight deviations from the recipe in the synthesis of diazo amino compounds, associated with non-observance of the HrN medium, lead to side processes and the formation of undesirable impurities (symmetrical triazenes).

The authors of the present invention, in order to eliminate the aforementioned deficiencies in the synthesis of diazo-amino compounds, suggest using sulfonium diazoniums for the preparation of triazenes, their introduction into the process in the form of an aqueous solution or suspension.

Diazo amino compounds with this synthesis method are very pure and can be primed with no pre-treatment to prepare mixtures with different azo components.

Due to the high purity of this kind of mixtures, insoluble ice dyes obtained from them on a fiber, in a substrate, or in a substance have a higher concentration compared to conventional mixtures.

Residues of mother solutions from the synthesis contain mainly aromatic sulfonic acids and can be added to the re-preparation of diazonium sulfo salts.

The preparation of diazo amino compounds is carried out by pouring solutions or from spenzes of diazonium sulfosalts into a solution of a stabilizer salt. The process occurring in this case can be expressed by the following scheme:

Of N

i K - N - OSOa R -1- R S Oj Xa

ill N

- R - N; i - o: H {rsg, H. .

Sulfonic acids have a more acidic character than the diazo amino compounds and remain

in solution in the form of sodium salts, while the diazo-amino compound precipitates as a precipitate, free from impurities of inorganic salts.

Impurities of aromatic sulfonic acids to diazo.mino compounds improve the quality of inks from the diazo compounds and nitrogen compounds, so in some cases it is more advantageous not to wash the triazene with water, to leave small amounts of aromatic sulfonic acids, or even add them to the finished product.

Example 1: 39 g of 2,5-dichlorodiazabepzol-4-methyl-3-nitrobenzenesulfonic acid salt are dissolved in 200 ml of water and the solution is poured, with a good cross, into a concentrated aqueous solution of 26.3 g of 2-methylamine-4-sulphobe sodium salt acid It gives out a yellow crystalline precipitate of the Diazoamino compound, which is filtered, washed on the filter with a solution of sodium chloride and a substance.at at 40. The yield of the diazoamino compound is 92% of the theoretically possible. The filtrate from the diazo-amino compound is used to re-obtain the dichlorochiso-benzene sulphate salt using conventional methods.

Example 2. A suspension of 30.8 g of sulphonic salt obtained from dX sulfonaphthalene and 4-chloro-o-t-luidine in 50 ml of water is poured, with good stirring, into a solution of 24.9 g of the sodium salt of 4-sulfo-2-aminobenzoic acid. It precipitates a precipitate of the Diazoamine compound, which is further processed as; described in example I.

The output is quantitative.

Example 3. Sulfonate salt, obtained from m-chloroaniline and o-dichlorobenzenesulfonic acid, in an amount of 0.1 gr-mol. suspended in 50 ml of water.

Susnenz is poured into a solution of 24.9 g of the sodium salt of 2-amino: 4 sulfobenzoic acid in 50 ml of water. A yellow crystalline dia.azo amino compound .6 falls out in almost quantitative yield.

Subject invention

Claims (4)

1. A method for the preparation of diazoamino compounds by the interaction of a diazonium with a primary or secondary amine containing groups that promote its solubility, -Distinguished by the fact that diazonin is used in the form of an aqueous solution or suspended from it with an aromatic sulfonic acid. 2. Application obtained under item 1 diazomino compounds to obtain mixtures with different azo-components. 3. Use of the mixtures obtained in accordance with claim 2 to obtain insoluble azo dyes on a fiber, on a substrate, and chi in substance. 4. The method according to claim 1, which also applies to the fact that when performing its mother liquors, it is used for the re-production of sulfonium diazonium salts.