CH261271A - Process for the preparation of a new monoazo dye. - Google Patents

Description

  

  Process for the production of a new monoazo dye. The invention relates to a process for the preparation of a new monoazo dye which is obtained by adding N-ss-oxy ethyl-N-ss'-phenylethyl-m-aminotoluene, diacotized p-nitroaniline and a sulfurizing agent to one another in such a way Implementation brings

      that the oxyethyl group is converted into the corresponding sulfuric acid ester group and the diazo radical enters the 4-position to the tertiary nitrogen atom.

    To obtain the new dye, N-ß-oxyethyl-N-ss'-phenylethyl-m-aminotoluene either first couple with diazotized p-nitaniline and then convert the coupling product into the corresponding sulfuric acid ester or first sulfate and couple the product obtained with diazotized p-nitroaniline.



  The new dye forms a dark red powder which is soluble in water to form a red solution and in sulfuric acid to form a dull yellow solution.



  <I> Example: </I> 13.8 parts of p-nitr aniline are diazotized. The cooled to 5 to 100 C solution of the azo compound is gradually stirred with a cooled solution of 35.7 parts of the sodium salt of the sulfuric acid ester of N-ß-oxyethyl-N-ßs'-phenylethyl-m-aminotoluene in 400 parts of water, which contains enough sodium carbonate to keep the mixture alkaline to brilliant yellow, was added.

      The suspension of the monoazo dye is stirred for two hours. The dye is then filtered off, washed with 2.5% strength aqueous sodium chloride solution and dried at 30 to 400.degree.



  The new dye forms a dark red powder, which dissolves in water under an image trough of a red solution and in sulfuric acid to form a pale yellow solution. It dyes cellulose acetate artificial silk in crimson red shades, provided the dyeing is carried out from a neutral dye bath containing Glauber's salt or sodium chloride, the dyeings produced having good fastness properties against wet treatment and light as well as good etchability and being fast to sublimation.



  The sulfuric acid ester of N-ss-oxyethyl-N-ss'-phenylethyl-m-aminotoluene can be obtained by that NT-ss-oxyethyl-m-toluidine with ss-phenylethyl bromide in boiling, aqueous suspension in the presence of Brings lime to the formation of N-ss-Oxyäthyl-N-ss'-phenylethyl-m-aminotoluene (bp. 216 to 2200 C / 20 mm) to implement.

   This latter compound is converted into its sulfuric acid ester by treatment with chlorosulfonic acid in an ethylene dichloride solution.

 

Claims (1)

PATENTA <B> N </B> SPRUCH Process for the preparation of a new monoazo dye, characterized in that N-ss-oxyethyl-N-ss'-phenylethyl-m-aminotoluene, diazotized p-nitroaniline and a sulfurizing agent are reacted with one another in such a way brings, that the oxyethyl group is converted into the corresponding sulfuric acid ester group and the diazo radical enters the 4-position --tun tertiary nitrogen atom. The new dye forms a dark red powder, which is soluble in water under an image trough of a red solution and in sulfuric acid to form a dull yellow solution. SUBCLAIMS: 1. Process according to patent claim, characterized in that N-ss-oxyethyl-N-ss'-phenylethyl-m-aminotoluene is coupled with diazotized p-nitroaniline and the coupling product is sulfated to the corresponding sulfuric acid ester. 2. Process according to patent claim, characterized in that N-ss-oxyethyl-N-ss'-phenylethyl-m-aminotoltzol sulfated and the product obtained is coupled with diazotized p-nitroaniline.