CH203426A - Process for the preparation of a polyazo dye. - Google Patents

Description

  

  Process for the preparation of a polyazo dye. It has been found that new diazotizing dyes can be obtained by using yellow pyrazolone dyes of the general formula AN = NB, where A represents the remainder of any diazotizing component, which can also contain azo groups, and B represents the remainder of a 1- Aminoarylpyrazolones,

      with acid halides of organic sulfo or carboxylic acids which contain a substituent which can be converted into an amino group, such as a nitro group or an N-acyl radical, on an aromatic nucleus, and converts the substituents mentioned into the amino group, e.g. B. by reduction or saponification.

    Suitable acid halides of the type mentioned are, for example, nitrobenzoyl halides, nitrobenzene sulfohalides, nitrophenyl acetic acid halides, nitrobenzophenonecarboxylic acid halides, and also the core substitution products of the compounds mentioned, preferably those with negativating substituents, such as.

   B. -N0_, -CO-, -, S02-, -C = N, halogen etc.



  The same dyes can of course also be produced in such a way that aminopyrazolones are condensed with the above-mentioned acid halides of organic sulfo or carboxylic acids and then in any order with a diazo or. Coupling the diazoazo compound and converting the substituent which can be converted into the amino group into the amino group.



  Compared to known dyes which contain aminoarylpyrazolone and its derivatives as the end component, the new dyes are distinguished by the fact that they are dyed onto the fiber and, after diazotizing and developing with f-naphthol, give significantly more yellow tones. Using the process described, it is possible to produce diazotization dyes which, when developed with f-naphthol, give yellow colorations.

   Since such dyes are not yet known and since there is great interest in practice in diazotization dyes which can be developed to yellow with β-naphthol, the process represents a significant technical advance.

      The subject of the present patent is a process for the production of a polyazo dye. The procedure is characterized by the fact that the procedure used in Switzerland is used. U.S. Patent No. 190894 disazo dye of the constitution
EMI0002.0008
         diazotized, coupled with the condensation product of m-aminophenylpyrazolone -3-carboxylic acid and m-nitrobenzoyl chloride and reduced the nitro group to the amino group.

   The new dye is a red-brown powder and dyes cotton in yellow tones after diazotizing and developing with ss-naphthol.



       Example: 219 parts of m-aminophenylpyrazolone-3-carboxylic acid are dissolved neutrally in 3000 parts of water with the addition of soda and treated with m-nitrobenzoyl chloride at 65 to 70 ° C., the reaction always being kept slightly alkaline by adding an acid-binding agent until the amino group can no longer be detected by diazotization. When the reaction is complete, it is made clearly alkaline, heated for a short time and isolated after cooling by adding acid.



  36.8 parts of the intermediate product thus obtainable are in the presence of 30 Tei len soda with the diazo compound from 65 parts of the body
EMI0002.0030
    coupled, then with 42 parts of sodium sulphide crystalline. reduced. The isolated dye dyes cotton after diazotization and development with j3-naphthol in more yellow shades than the corresponding dye with non-condensed aminophenylpyrazolonecarboxylic acid.

 

Claims (1)

PATENT CLAIM: Process for the production of a polyazo dye, characterized in that one uses the process of Switzerland. Patent No. 191) 894 available disazo dye of constitution EMI0002.0043 diazotized, couples with the condensation product of m-aminophenylpyrazolone-3-carboxylic acid and m-nitrobenzoyl chloride and reduces the nitro group to the amino group. The new dye is a red-brown powder and, after diazotizing and developing with ss-naphthol, dyes cotton in yellow tones.