CH309183A - Process for the preparation of a water-insoluble disazo dye. - Google Patents

Description

  

  Process for the preparation of a water-insoluble disazo dye. It has been found that a valuable new water-insoluble disazo dye can be obtained. when 1 mol of diazotized 1.-aniino-2-methoxybenzene is obtained in acidic medium with 1.

       Mol of 1-amino-2-methoxy-5-methylbenzene couples, the aminomonoazo compound obtained is further diazotized and coupled with 1 mole of oxybenzene.



  The new water-insoluble disazo dye, when dispersed in the usual way, dyes synthetic polyamide fibers in yellow-orange shades with good light, wet and sublimation fastness properties. Striped nylon is evenly covered. The new disazo dye can also be used at elevated temperature. Dyeing of polyester and polyaeryl nitrile fibers can be used.

   Also draws. it is characterized by its very good drawability and great depth of color on Acetatreyon, the color tone corresponding to that on synthetic polyamide fibers. The new, water-insoluble disazo dye is also suitable for coloring paints, oils, synthetic resins or synthetic fibers in the mass.



  In the following example the 'files mean weighted parts. <I> Example: </I> \? 4.5 parts of 1-amino-2-methoxybenzene are dissolved in 400 parts of water and 64 parts of concentrated hydrochloric acid and the solution is cooled to 0 by adding 400 parts of ice. The 1-amino-2-methoxybenzene is then diazotized with a solution of 14 parts of sodium nitrite in 40 parts of water.

   When the diazotization is complete, a solution of 27 parts of 1-amino-2-methoxy-, 5-methylbenzene in 500 parts of water and 32 parts of concentrated hydrochloric acid is added dropwise to the diazo mixture, and 45 parts of sodium acetate are added to accelerate the coupling. When the coupling has ended, 200 parts of sodium chloride are added to the reaction mass and the monoazo compound which has separated out is filtered off.

   It is stirred into 2000 parts of water and 64 parts of concentrated hydrochloric acid, the slurry is adjusted to 10 to 15 by adding ice and diazotized with a solution of 15 parts of sodium nitrite in 50 parts of water. The diazole solution is then filtered and the filtrate is washed with a solution of 20 parts of oxybenzene in 200 parts of water, 48 parts of sodium carbonate,

       21 parts of 36 percent sodium hydroxide solution and 80 parts of sodium acetate combined at 0 to 5, coupling to the disazo dye occurs. This is filtered off, washed neutral and dried. The new, water-insoluble disazo dye is a brown-red powder that contains acetate silk, polyamide fibers. such as nylon and Perlon, and polyester fibers such as Dacron, dyes in yellow-orange tones with excellent fastness properties.



  In comparison, the dye which carries the remainder of the aminobenzene as the initial component is 3 @ 5% and that with the 1-amino-3-methylbenzene read as the initial component is 55% weaker in color than the dye of the example.

 

Claims (1)

PATENT CLAIM: Process for the preparation of a water-insoluble disazo dye, characterized in that 1 mol of diazotized 1-amino-2-methoxybenzene is mixed in an acidic medium with 1 mol of 1-amino-2-methoxy <B> -, 5 </B> - methylbenzene couples, the aminomonoazo compound obtained is further diazotized and coupled with 1 mol of oxybenzene. The new water-insoluble disazo dye, when dispersed in the usual way, dyes synthetic polyamide fibers in yellow-orange shades with good light, wet and sublimation fastness properties. 'Striped nylon is evenly covered. The new disazo dye can also be used to dye polyester and polyacrylonitrile fibers at elevated temperatures. In addition, it is characterized by very good drawing ability and great depth of color on Aeet.at- reyon, whereby the color tone corresponds to that on synthetic polyamide fibers. The new water-insoluble disazo dye is also suitable for dyeing. of paints, oils, synthetic resins or artificial fibers in the mass.