CH148763A - Process for the preparation of poly-azo dyes. - Google Patents

Description

  

      Process for the preparation of poly azo dyes. Dis- and Tris-Azofarbs.toffe of the type Peri-aminona.phtol-sulfonic acid + Mittelkom component (+ middle component) -i- 2-amino-5-oxynaphthalen-7-sulfonic acid or derivatives thereof are by the German patent No. 1981 ( 12, as well as its addition DR. P. No. <B> 202117 </B> became known.

   The coupling for dis- or. In this process, trisazofa is consistently produced in a soda-alkaline solution with good yield.



  If one tries in an analogous way to build up dis- and poly-azo dyes from diazotized amino mono- or disazo compounds which contain 1.-amino-8-oxynaphthalene or one of its derivatives as initial components,

       It shows which end components, instead of 2-amino-5-oxynaphthalene-7-sulfonic acid or one of its derivatives, contain an N-heterocyclically substituted 1-amino-8-oxynaphthalene or a derivative thereof that incomplete coupling occurs in soda-alkaline or ammoniacal solution. Rather, the Disazov connections are largely decomposed.



  In contrast, a process has now been found by which the dyes of the type mentioned can be produced in good yield and excellent purity. E is indicated by it. that when coupling diazotized amino-azo compounds from diazotized 1-amino-8-oxy-naphthalenesulfonic acids and any middle components of the aromatic series with.

   an N-heterocyclically substituted 1-amino-8-oxynaphthalene sulfonic acid makes the last cup in the presence of a pyridine base.



  This leads to a valuable type of dye that was previously inaccessible or very difficult to access. The products draw surprisingly well on the plant-based fibers in blue. blue-green or green tones with excellent authenticity. If there is also a diazotizable amino group in the heterocyclic residue of the 1-amino-8-oxynaphthalene used as the end component,

       this amino group can be further changed, for example by treatment with acid chlorides or anhydrides (such as phosgene, thiophosgene, acetic anhydride, benzoyl or nitrobenzoyl chloride, etc.) or by treatment with heterocyclic compounds with mobile halogen atoms, such as chloroquinazolines, Chloronaphtalazines,

          2-Ha, logenbenzothiazoles, cyanuric chloride etc. or also further diazotization and coupling in substance or on the fiber.

      <I> Example: </I> The diazo compound from 4892 parts by weight of the azo dye. Dianotated 1-amino-8-oxynaphthalene-3,6-disulfosä, ure and 3-amino-4-cresolmeihy ether is pasted with ice. The thin paste is added with stirring at 0 to 5 to a solution of <B> 580 </B> parts by weight of the condensation product of 1 part cyanuric chloride and 1 part 1-amino-8-oxynaphthalene-3. 6-disulfosair (, and 1 part aniline.

   The 3-chlorine atom has been replaced by _Ivdroxy1. The coupling takes place immediately to give a blue dye, which is worked up in the usual white. It dyes cotton in blue tones that are very lightfast.

 

Claims (1)

PATENT CLAIM: Process for the preparation of poly-azo dyes by coupling the dianotated aminoazo compounds, which are obtainable from dia.zotier- ten 1-amino-8-oxynaphthalene sulfonic acids and any middle components of the aromatic series, with N-heterocyclically substituted ones 1-Amino-8-oxynaphthalenesulfonic acids, characterized in that the last coupling is carried out in the presence of a pyridine base.