CS262065B1 - New reactive dye of its preparation - Google Patents

Abstract

A reactive vinylsulfone type dye of the general formula I, where X is hydrogen, sodium, potassium, magnesium or an alkaline earth metal, is prepared by diazotizing (3-sulfatoxyethylsulfonyllocresidin in an aqueous medium and coupling the diazonium salt suspension with 1-naphthol-4-sulfonic acid in a weakly acidic to neutral medium and dyeing cellulose textiles a deep red neutral shade.

Description

The present invention relates to a novel reactive dye of a deep red neutral shade 8 of a process for its preparation.

Dyes with a phosphatoxyethylsulfonyl group are only slowly (activated) in the alkaline bath 1 with a strong alkali, while hydrating to the non-reactive hydroxyform; the colors are then poorly abundant. This type of dye also includes a red dye prepared from β-phosphatoxyethylsulfonylcresidine and 1-naphthol-4-sulfoacid according to AO 190 949, dated September 1, 1981, having the aforementioned disadvantages; The active azo component / β-phosphatoxyethylsulfonylcresidine used for its preparation is difficult to access and economically expensive.

It has now been found that these disadvantages are overcome by the dye of the present invention

where

X is hydrogen, sodium, potassium, magnesium or an alkaline earth metal, providing a coloring of a deep red tint (species, absorbance coefficient = 36); Vinylation occurs already with the use of a weak base such as NaHCO 3, no undesired hydroxy form is formed in the bath and the subsequent thermal treatment (steaming, thermofix) binds the vinyl form quantitatively to the fiber.

According to the invention, the process for preparing a binder is characterized in that β-sulfatoxyethylsulfonylcresidine is diazotized in an aqueous medium and the diazonium salt suspension is coupled with 1-naphthol-4-sulfoacid in a weakly acid to neutral medium.

The dye according to the invention dyes all kinds of cellulosic textile material both by pulling and flaking methods, with the highest stability - up to 8 hours - of the flaking bath composition: 20 to 40 g of dye + 100 g of urea + 20 g of NaHCO3 in 1000 ml of water; after the fabric has been tilted between rollers, dried at 60 ^° C and thermofixed at 140 ° C for 2 to 5 minutes, a deep red color of neutral shade (λ _max = 503 nm) is obtained.

Example 1

97.6 parts of λ-sulfatoxyethylsulfonyl cresidine are stirred in 600 parts of water to a fine suspension, 48 parts by volume of conc. hydrochloric acid, 300 parts of ice and diazotized with a total of 120 parts by volume of a solution containing 20.8 parts of sodium nitrite. 67.3 parts of 1-naphthol-4-sulfoacid are stirred in 1200 parts of water, the slight acidic reaction is neutralized with NaHCO 3 and the solution is filtered from an insoluble residue. A suspension of the above-prepared diazonium salt was added to the filtrate while blurring the acidic reaction to NaHCO3 conglow. After all of the diaza has been poured in, the NaHCO 3 reaction is adjusted to pH = 5 to 6.5 and stirred for 2 hours when the coupling is complete. Add 13 parts of kieselguhr and after 20 min. mixing and filtering, the filtrate (2,400 parts by volume) was salted out by adding 240 parts of KCl and stirring for 20 hours. The salted dye is filtered and, after good suction, dissolved in 1900 [mu] l of water and dried.

171-180 parts of a dye coloring the cellulosic textile material with a deep red neutral shade of good fastness are obtained. When parts are mentioned in the text, parts are by weight unless otherwise stated.

Claims (2)

A novel reactive dye of a deep red neutral shade of the formula wherein X is hydrogen, sodium, potassium, magnesium or alkaline earth metal. 2. A process for the preparation of a novel reactive dye of a deep red neutral shade of formula I according to claim 1, characterized in that the β-sulfatoxyethylsulfonyl cresidine is diazotized in an aqueous medium and the diazonium salt suspension is coupled with a 1-naphthol-4-sulfoacid.