DD217532B1 - METHOD FOR PRODUCING A HOMOGENOUS COLOR MIXTURE - Google Patents

Description

Field of application of the invention

The invention relates to the preparation of a homogeneous dye mixture for the direct dyeing of native and regenerated cellulose fibers in navy shades.

Characteristic of the known technical solutions

Dark blue shades on native and regenerated cellulose fibers dyed with Oirektfarbstoffen generally show only moderate wet fastness. If higher demands are made on the wet fastness, such. B. grades between 4 and 5 in the water fastness, the wash fastness 40 ° C, or the perspiration fastness one used the diazotierbaren direct dyes. The most important representative for this use was C.J. Direct Blue 2, a benzidine dye whose production is banned in most industrialized countries for reasons of health protection. For the dye mentioned so far no real replacement could be found. Known simple blue direct dyes do not achieve the nuance and fertility of said diazo blue and had to be adjusted in poorer overall economy due to poorer drawability on cellulose fibers additionally with suitable correction dyes on the corresponding marine blue shade.

Object of the invention

The aim of the invention is to find a dye CJ. Direct Blue 2 substituting dye.

Explanation of the essence of the invention

The object of the invention was the preparation of a dye CJ. Direct Blue 2 similar dye with avoidance of benzidine as starting material and to eliminate the need for correction of the shade on a dry way.

It has been found that the objective and object can be obtained corresponding dyes when diazotized a hydrochloric acid aqueous solution of 4,4'-diaminodiphenylamine-2-sulfonic acid with 94 to 97% of the amount required for bisdiazotization Na-nitrite, the reaction product with one of the amount of Na nitrite corresponding amount of a customary in the technical synthesis Cleve acid mixture, which is known to 46 to 48% of 1 -aminonaphthalene-6-sulfonic acid, 44 to 46% of i-aminonaphthalene-7-sulfonic acid and 6 to 10% of 1-aminonaphthalene-8-sulfonic acid, disengages in the weakly alkaline range, the dye mixture obtained in a known manner completely bis-diazotized and also in a known manner with respect to 4,4'diaminodiphenylamine-2-sulfonic acid doubly molar amount Coupling 2-amino-5-naphthol-7-sulfonic acid in an alkaline medium.

With the dye mixture obtainable according to the invention, dark blue shades without correction or shading dyes are obtained on cellulose fibers of whatever type whose wet fastnesses are comparable to those of CJ. Direct Blue 2 are similar. The dye mixture according to the invention has compared to the CJ. Direct Blue 2 three advantages:

1.) It is not a benzidine dye and thus there are no production bans or restrictions.

2.) It is not a diazotization dye and therefore the application process is simpler and more productive.

Diazotization dyes are dyed, rinsed, diazotized, rinsed, developed and rinsed again, d. H. applied by a so-called three-step method. The dyestuff mixture obtained according to the invention is dyed, rinsed, cationically treated and rinsed, i. H. applied by a so-called two-step method. 3.) Two-stage processes are not only more productive in comparison to three-stage processes, they also have a lower fresh water requirement and consequently also a reduced waste water supply due to the lower number of rinsing processes.

Thus, the dye mixture obtainable according to the invention represents a genuine new development, which takes into account today's requirements with regard to health protection and environmental protection and, moreover, contributes to an increase in production in the textile industry.

embodiment

27.9 parts of 4,4'-diaminodiphenylamine-2-sulfonic acid are stirred in 400 parts of water, mixed with 40 parts of hydrochloric acid and diazotized by adding 13.1 parts of sodium nitrite at 1O ⁰ C. This reaction mixture is disengaged with a cooled to 0 ⁰ C solution of 42.4 parts of the obtained in the synthesis Clevesäureisomerengemisches in 700 parts of water in the weak alkaline range, bisdiazotiert the resulting dyes with 13.8 parts of sodium nitrite in a known manner and with a solution of 47.8 parts of 2-amino-5-naphthol-7-sulfonic acid coupled in the alkaline range

 The homogeneous dye mixture is isolated in the usual manner, dried and ground. There are obtained 140 parts of dye mixture.

With 1.25 parts of the resulting dye mixture 100 parts Zellusloseregeneratfaser be treated by the dye mixture is dissolved in 50 parts of water by boiling and the solution thus prepared is diluted with 150 parts of water to the dyebath. The dyebath will continue to calcite 20 parts of sodium sulfate. added. The dyeing is carried out for 45 minutes at boiling temperature. After this treatment, the fiber is rinsed in clear water, aftertreated in the usual way in the cold medium with a cationic fixing agent, rinsed again and dried. The cellulose regenerated fiber is now dyed in a flowery full navy blue and the dyeing corresponds in its fastness to the Diazofärbung with CJ. Direct Blue 2.

Claims (2)

Invention claim: A process for the preparation of a homogeneous dye mixture, that native and regenerated cellulose fibers navy blue in the shade and the wet fastness of the Diazofärbung of CJ. Direct Blue 2 according dyed directly on the basis of 4,4'-diaminodiphenylamine-2-sulfonic acid as a diazo component and of aminonaphthalene and Aminohydroxynaphthalinsulfonsäuren as coupling components, characterized in that the aqueous hydrochloric acid solution of 4,4'-diaminodiphenylamine-2-sulfonic acid with 94 to 97% of the amount of NaNO ₂ required for complete bis-diazotization, the reaction products obtained with a quantity corresponding to the nitrite use of a mixture of 46 to 48% by weight of i-amino-naphthalene-6-sulfonic acid,
From 44 to 46% by weight of 1-amino-naphthalene-7-sulphonic acid and
6 to 10% by weight of i-amino-naphthalene-8-sulfonic acid coupled, the dye mixture now obtained completely bis-diazotized in a known manner and with a relative to the 4,4 '· diaminodiphenylamine-2-sulfonic acid doubly molar amount 2-amino-5-naphthol-7-sulfonic acid is coupled alkaline.