CS260628B1 - Unsymmetrical 1: 2 metal complex dyes and method of their preparation - Google Patents

Abstract

Unsymmetrical 1:2 metallocomplex dyes with two sulfo groups based on chromium complexes of formula I, where the substituents Ai and Az are different and denote —NOz, —Cl, —SOs", with one of the substituents always denoting —SO3- and M+ denoting Na+ and/or NHi+.

Description

The present invention provides unsymmetrical 1: 2 metal-complex chromium complex dyes of formula I

Cr ~ N ~ N

3H wherein the substituents A 1 and A 2 are different and denote -NO 2, -Cl, -SO 3 ^- , wherein one of the substituents always denotes "SO 3" and M denotes Na ⁺ and / or NH 1 ⁺ .

These dyes are new and usable for dyeing woolen and polyamide textile materials that dye highly stable blacks.

Previously known metallocomplex dyes are in the form of 1: 1 fluffy, 1: 2 symmetrical and 1: 2 unsymmetrical complexes containing one sulfo group per molecule. A disadvantage of 1: 1 metal-complex dyes is their low pull-out from neutral and weakly acid dye baths. A disadvantage of symmetrical 1: 2 metal-complex dyes is that it is difficult to achieve highly stable dyes for dyeing wool and polyamide. The disadvantage of 1: 2 unsymmetrical single-sulfo metal complex dyes is their lack of solubility and leveling in conventional dyeing processes.

It has now been found that said drawbacks do not exhibit the 1: 2 metal-complex dyes of the two sulfogroups of the invention, which are based on the unsymmetrical 1: 2 chromium complex of constitution I, wherein the substituents A 1 and A 2 are as previously defined.

Unsymmetrical metal-complex dyes of formula I according to the invention are readily obtainable by reacting compounds of formula II wherein A 1 and A 2 are as previously defined, with a 1: 2 chromium complex of formula (III)

or by treatment with an azo compound of formula IV

to 1: 1 chromium complexes of formula V

N = N where Δι and Az are as previously defined, in an alkaline, neutral or slightly acidic environment at temperatures usually 80 to 100 ° C.

The process for the preparation of unsymmetrical 1: 2 chromium complexes of the formula I according to the invention is preferably carried out in a reaction medium containing ammonium or alkali carbonates. The presence of these substances makes it easier to carry out the complexing reaction in a high concentration of reacting components.

The advantage of the process for the preparation of 1: 2 unsymmetrical complexes of the formula I according to the invention is the high purity of the dye, since the currently used methods for the synthesis of unsymmetrical 1: 2 metalocomplex dyes. possible unsymmetrical 1: 2 metal complex dyes.

In addition to the high solubility of the dye, the product I is distinguished by excellent coloristic properties and high light fastness.

The advantage of the process of preparing 1: 2 asymmetric complexes according to the invention is to achieve high production on a simple production equipment and to guide the production process so that it is possible to work with waste-free technologies. Another advantage of 1: 2 unsymmetrical chromite complexes with two sulfo groups is that it is not necessary to isolate the dye itself before drying.

The invention is further illustrated by the following non-limiting examples.

Example 1

To a suspension of 0.02 mol of 1: 1 chromium (III) complex in 400 mL of H 2 O was added 0.02 mol of azo compound of formula II where A 1 is -SO 2 - and A 2 -Cl and pH was adjusted with 2.1 ml of sodium hydroxide solution c ] = 10 mol / l to 10. 0.010 mol of sodium bicarbonate was added and the reaction mixture was heated at 90-95 ° C for 2 hours, and the resulting dye solution was sclerated and dried to give 22.4 g of dye I, where A 1 is - SO: ma A2 is —Cl, dyeing wool and polyamide materials to black with high light fastness.

Example 1 a d 2

0.02 mol of azo compound IV was added to a suspension of 0.02 mol of a 1: 1 chromium complex of formula V wherein A 1 is -NO 2 and Az is -SO 3 - in 400 ml of water, adjusted to pH 8 with ammonia solution, 0, 02 mol of sodium carbonate and the reaction mixture was maintained for 1 hour at 90-95 C. a solution of ³ was formed barvlva zklerován and dried. 23.8 g of a dye of formula I were obtained, wherein A 1 is -NO 2 and A 2 is -SO 3 ^- , dyeing wool and polyamide materials to a high shade black.

Claims (3)

PURPOSE OF THE INVENTION 1. Unsymmetrical 1: 2 metal-complex dyes with two sulfo groups based on chromium complexes of formula I wherein the substituents A 1 and A 2 are different and denote —NOa, —Cl, —SO3, where one of the substituents always denotes —SO3 and M denotes Na ⁺ and / or NH 4 ⁺ . 2. A process for the preparation of 1: 2 chromium complexes according to claim 1, characterized in that the azo compound of the formula II is optionally reacted with an azo compound of the formula IV OH HO (II) with a 1: 1 chromium complex of azo dyes of formula V wherein the substituents A 1 and A a are as defined above, are reacted with a 1: 1 chromium complex of formula III O.J4 £, δ / 1 in ^y o ....... \ a v. (IN) Where the substituents A 1 and A 2 are as previously defined. 3. A process for the preparation of asymmetric 1: 2 chromium complexes according to claim 1 or 2, characterized in that the dye synthesis is carried out in an alkaline, neutral or slightly acidic medium.