CH426052A - Process for the preparation of water-insoluble monoazo dyes - Google Patents

Description

  

  Process for the preparation of water-insoluble monoazo dyes The main patent relates to a process for the preparation of water-insoluble monoazo dyes of the general formula
EMI0001.0005
    where R1 is the residue of a diazo component of the benzene, naphthalene or heterocyclic series free of water-soluble groups, both R being the same or different low molecular weight alkyl radicals,

   which together men have at least one negative substituent and at least one 1 to 5 carbon atoms aufwei send -O-acrylic radical, and wherein the core A can carry further substituents with the exception of groups which make water soluble.

   They are prepared by converting 1 mol of the diazo compound from an amine of the benzene, naphthalene or heterocyclic series free of water-solubilizing groups, 1 mol of a tertiary amine of the formula
EMI0001.0020
    where both R 'denote the same or different low molecular weight alkyl radicals which together have at least one negative substituent and at least one hydroxyl group,

   and at least 1 mole of a functional derivative of 1 to 5 carbon atoms that acid interacts with.



  The tertiary amines of the composition (II) have by definition in the N-alkyl radicals at least one negative substituent (for example a halogen atom, a nitrile, a nitro or a C-acyl group) and at least one hydroxyl group.



  In addition, they can be substituted in the 2- and / or 5-position of the benzene nucleus by halogen atoms or low molecular weight alkyl, alkoxy or acylamino groups, the hydrogen atoms of which are optionally completely or partially replaced by fluorine.



  It has now been found that water-insoluble monoazo dyes of the general formula
EMI0001.0048
    have particularly advantageous properties in some respects. In this formula, Y and X denote identical or different halogen atoms. The other symbols are the same as in the main patent. The dyes are obtained when 1 mol of the diazo compound is derived from an amine of the general formula which is free from water-solubilizing groups
EMI0001.0052
    in which X and Y have the aforementioned meaning, implemented in the manner indicated in the main patent specification.



  The new dyes attract z. B. on cellulose ester fibers (e.g. acetate synthetic silk, triacetate synthetic silk), synthetic polyamide fibers (e.g. nylon), polyvinyl fibers, terephthalic acid ester fibers (e.g. terylene, dacron, registered trademarks) and polyacrylonitrile fibers (e.g. Orion, Dynel, Acrilan, registered trademarks) in orange, yellowish-brown tones.

   The colors obtained with them are very light, smoke, sweat, wash and sublimation fast. The particular advantage of the new dyes is that they can be combined with other dyes for the production of dyeings in fashion shades.



  The parts mentioned in the following example are parts by weight.



  <I> Example 1 </I> 83 parts of 2,6-dichloro-4-nitro-1-aminobenzene who entered the nitrosylsulfuric acid prepared from 450 parts of concentrated sulfuric acid and 28.5 parts of sodium nitrite. The mixture is stirred for 4 hours at room temperature,

      loads the viscous reaction mass onto 1400 parts of water and 2400 parts of ice and destroys a small excess of nitrous acid with amidosulfonic acid. A solution of 76 parts of N-cyanoethyl-N-oxyethylaniline in 50 parts of 301laigen hydrochloric acid and 30 parts of ice is added to the clear diazo solution. Coupling occurs immediately.

   After stirring for 1 hour, the dye suspension obtained is diluted with 7000 parts of water, filtered, washed free of acid and dried.



  50 parts of the 2,6-dichloro-4-nitro-4 '- (N-cyanoethyl N-oxyäthylamino) 1,1'-azobenzene thus obtained are heated to boiling together with 200 parts of acetic anhydride for 2 hours. After cooling, small amounts of an impurity are filtered off and the filtrate is then diluted with 750 parts of ethyl alcohol. The new dye crystallizes out when left to stand.

   In the purified state it melts at 132-133. He can be in übli cher way, z. B. by grinding with a dispersing agent and with sodium sulfate, process into a dye preparation with which acetate synthetic silk and polyterephthalic acid ester fibers in yellow-tinged orange-brown shades with excellent fastness properties, especially with excellent light,

   Fastness to smoke gas and sublimation, can dye.



  A dyebath is prepared from 0.6 parts of the dye thus obtained and dispersed with the aid of Turkish red oil, 6 parts of a fatty alcohol sulfonate and 3000 parts of water. 100 parts of acetate rayon are introduced into the bath at room temperature, heated to 80 within one hour and held at this temperature for 1 hour. After this time the dyeing process is finished.

   The material to be dyed is taken out of the bath, rinsed and dried. It is colored in yellowish orange-brown tones with excellent fastness properties.



  To improve the dispersibility, the dye can be used prior to the dyeing process with suitable wetting agents, dispersants or emulsifiers, preferably in the presence of inorganic salts, e.g. B. sodium sulfate, who grind the. It can also be intimately mixed as an aqueous paste with a dispersing agent and converted into a dye powder by suitable drying.

   Synthetic polyamide fibers are dyed using the same method at 90-100, terephthalic acid ester fibers at 120-130 under pressure or at 90-100 in the presence of transfer agents.



  The same dye is obtained when 1- (N-cyanoethyl-N-acetoxyethylamino) benzene is used as the coupling component.



  Dyes with similar properties are obtained by using 2,6-dibromo-4-nitro-l-aminobenzene as the diazo component or 1- (N-cyanoethyl-N-acetoxyethylamino) -3-methylbenzene as the coupling component.

      <I> Example 2 </I> 29.6 parts of 1-amino-2,6-dibromo-4-nitrobenzene are diazotized according to the instructions given in Example 1, the reaction mass is poured into ice water and the excess of nitrous oxide is removed Acid with amidosulfonic acid and, if necessary, clarify the solution by filtering.

   A cold solution of 23.2 parts of 1- (N-cyanoethyl-N-acetoxyethyl-amino) -benzene in 100 parts of glacial acetic acid is then allowed to flow in at 0-5 and the mixture is stirred until the end Coupling reaction. The dye is filtered off. washes it acid-free and dries it. It melts at 130-133 C.

   Finely dispersed, it can be used to dye acetate silk or polyester fibers. Orange-brown dyeings with excellent fastness properties are obtained.

 

Claims (1)

PATENT CLAIM Process for the preparation of water-insoluble monoazo dyes of the general formula EMI0002.0140 in which X and Y are identical or different halogen atoms and both R are identical or different from one another low molecular weight alkyl radicals which together have at least one negative substituent and at least 1 to 5 carbon atoms having -O-acyl radical, and in which the nucleus A. can carry further substituents with the exception of water-solubilizing groups, characterized in that 1 mol of the diazo compound is obtained from an amine of the general formula which is free from water-soluble groups EMI0003.0001 in which X and Y are identical or different halogen atoms, 1 mol of a tertiary amine of the formula EMI0003.0004 in which both R 'are identical or different low molecular weight alkyl radicals, which together have at least one negative substituent and at least one hydroxyl group, and at least 1 mole of a functional derivative of 1 to 5 carbon atoms which the acid allows to act on one another. SUBClaims 1. The method according to claim, characterized in that the esterification reaction is carried out before the coupling reaction. 2. The method according to claim, characterized in that the esterification reaction is carried out after the coupling reaction.