CH418495A - Process for the preparation of monoazo dyes - Google Patents

Description

  

      Process for the preparation of monoazo dyes ES has been found that valuable monoazo dyes of the formula
EMI0001.0009
    obtained when a compound of the formula
EMI0001.0014
         where X is hydroxyl,

          Halogen or the radical O'- R5 (R4) -0- n-1 is diazotized,

          the diazonium compound thus obtained with a pyrazole derivative of the formula
EMI0001.0032
         couples and the coupling product is esterified with an alcohol of the formula Rä- (R4) n-1 OH (IV) if the diazo component is a compound of the formula (II)

      was used, where X is hydroxyl or halogen. In this formula, R1 is a hydrogen atom or an optionally substituted hydrocarbon radical, R2 is an optionally substituted, low molecular weight alkyl radical,

      a carboxylic acid ester group or an optionally substituted carboxylic acid amide group, R3 a hydroxyl or amino group, R4 an optionally substituted alkylene radical,

            RS is an optionally substituted cycloalkyl radical and n is a small integer.



  The phenylene solid A can be further substituted, but not by sulfonic acid groups or carboxyl groups. The radicals R1, R2, R4 and R5 also contain, if they are substituted, no sulfonic acid groups or carboxyl groups.



  Particularly preferred dyes of the formula (I) are those! Which, as radical R1, are unsubstituted or, for example,

   B. by halogen, especially chlorine or bromine, or alkyl, especially with 1 to 4 carbon atoms, substituted phenyl, the methyl group, a carboxylic acid ester group or an optionally substituted carboxamide group, the hydroxyl group as the substituent R,

       and an unsubstituted or e.g. B. by 1 to 4, preferably 1 to 2 carbon atoms: containing alkyl, alkoxy or alkylcarbonyl groups or by 1 to 2 halogen atoms, especially chlorine or bromine atoms,

       Substituted cyclohexyl radical as substituents R5 and in idenen the alkylene radical R4 contains 1 to 3 carbon atoms and in particular 1 carbon atom.



       Diazotization, coupling and esterification are carried out in the customary manner. For example, coupling is carried out in a weakly acidic to alkaline medium. For the esterification, the dried coupling product can be dissolved in an organic solvent, e.g.

   B. Chlorher- zol, are reacted with thionyl chloride and .anschkessend with an alcohol of the formula (IV).



  It is particularly advantageous to convert the new dyes obtained in this way from their use in a known manner into dye preparations. For this purpose, they are comminuted until the particle size in the mean is about 0.01 to 10 microns and in particular about 0.1 to 5 microns.

   The comminution can take place in the presence of dispersants or fillers. For example, the dried dye is ground with a dispersant, optionally in the presence of fillers, or kneaded in paste form with a dispersant and then dried in vacuo or by atomization.

   With the preparations obtained in this way, minn, after adding more or less water, can dye or pad or print in a so-called long or short liquor.



       When dyeing in a long liquor, up to about 20 g of dye per liter are generally used, when padding up to about 150 g per liter, preferably 0.1 to 1.00 g per liter,

   and when printing up to about 1-50 g in the kilogram of printing paste. The Flot tenverhältrns can be selected within wide limits; z. B. between about 1: 3 and 1: 200, preferably between 1: 3 and 1:80.



  The dyes are absorbed from aqueous .Suspension on moldings made of fully synthetic or semi-synthetic high molecular weight substances.

    They are particularly suitable for dyeing, padding or printing fibers, threads or fleeces, woven or knitted fabrics:

  from linear, aromatic polyesters and from cellulose 2 1/2 iacetate or cellulose triacetate. Synthetic polyamides, polyolefins, acrylonitrile polymerisation products and polyvinyl compounds can also be: colored with them. Particularly valuable dyeings are used on linear, aromatic polyesters; receive.

   These are generally polycondensation products of terephthalic acid and glycols, particularly ethylene glycol, and z. B. under the protected names Terylen, Diolen or Dacron in the trade.



  It is colored according to methods known per se. Polyesters can be dyed in the presence of carriers at temperatures between) about 80 and 125 C or in the absence of carriers under pressure at about 100 to 140 by the exhaust process.

    They can also be padded, padded or printed with the aqueous dispersions of the new dyes and the impregnation obtained can be fixed at about 140 to 230 ° C., e.g. B. with the help of water vapor or air.

   In the particularly favorable temperature range between 180 and 220 C, the dyes quickly diffuse into the polyester fiber and do not sublime again, even if these high temperatures are left to act for a long time. This avoids the annoying soiling of the dyeing apparatus.



       Cellulose 2 1/2 acetate is dyed preferably between about 65 and 80 C and cellulose triacetate at temperatures up to about 115 C. The most favorable pH range is between 2 and 9 and especially between 4 and B.



  Usually, the usual .Dispergiermittel are added, which are preferably artionic or nonionic and can also be used in a mixture with one another. About 0.5 g of dispersing agent per liter of dye preparation is often sufficient, but larger quantities, e.g. B.. Up to about 3 g per liter can be used. Amounts in excess of 5 g usually result in no further advantage.

   Known Artioni cal dispersants that come into consideration for the process are, for example, condensation products of naphthalenesulfonic acids and formaldehyde, especially Dinaphthyhnethandisulfonate, esters of, sulfonated succinic acid, Turkish red oil and alkali, alze of sulfuric acid esters ider fatty alcohols, z.

   B. Sodium cetyl sulphate, sulphite cellulose waste or their alkali salts, soaps or alkali sulphates of; Monoglycerides of;

          Fatty acids. Examples of known and particularly suitable nonionic dispersants are addition products of about 3-4.0 mol of ethylemoxide with alkylphenols, fatty alcohols or fatty amines and their;

          neutral sulfuric acid esters.



  When padding and printing, the usual thickeners are used, e.g. B. modified or unmodified natural products, for example alginates, British gum, gum arabic, crystal gum, locust bean gum, tragamt, carboxymethyl cellulose, hydroxyethyl cellulose,

      Starch or synthetic products such as polyacrylamides or polyvinyl alcohol.



  The colorations obtained are extremely genuine, e.g. B. excellent thermofixing, subliming, pleating, smoke gas, dyeing, dry cleaning, chlorine and wet fast, z.

   B. water, wash and perspiration resistant. Etchability and, reserve of wool and cotton are good. Outstanding;

      is the lightfastness, even in light tones, so the new. Dyes are also very suitable as mixing components for the production of pastel-colored fashion shades. The dyes are at temperatures up to at least 20 C and, especially at 8,

  0 to 140 C, resistant to boiling and reduction. This resistance is not adversely affected either by the liquor ratio or by the presence of dye accelerators.



  The new dyes, in combination with small amounts of blue dyes, are suitable for the production of cheaper, light, wash, sweat, chlorine, sublimated, pleated and thermofixed as well as etchable green dyes and together with red and blue dyes Production of real black colors. The parts mentioned in the examples are parts by weight and the percentages are percentages by weight.

   The temperatures are given in degrees Celsius.



  <I> Example 1 </I> 68.5 parts of p-aminobenzoic acid are mixed in 150 parts of concentrated hydrochloric acid and cooled to 0 with ice. It is diazotized at 0-5 with 35 parts of sodium nitrite in 100 parts of water. The mixture is stirred for 1 hour and the excess nitrite present is destroyed with amidosulfonic acid.



  For coupling, 87 parts of 1-phenyl-3-methyl-5-pyrazolone are dissolved in 250 parts of water and 50 parts of 301% sodium hydroxide solution. After the mixture has cooled to 0-5, the diazonium salt suspension is allowed to run in and the mixture is stirred at 3-5 'overnight. In the morning, the dye is filtered off and purified by reprecipitation from water.



  32 parts of the thus obtained; dried yellow pigment are mixed with 400 parts of chlorobenzene and 15 parts of thionyl chloride and kept at 120-130: until the evolution of hydrogen chloride gas has ended.

   The dye goes into solution. It is cooled and the 4- (4'-chloroearbonylphenylazo) -43-methyl-1-iphenyl-pyrazolone obtained is precipitated with petroleum ether and filtered off.



  34 parts of this compound are added to 150 parts of cyclohexanol and heated to 120-130 for 3 hours. The cooled mixture is poured into 1000 parts of water and the dye obtained is filtered off. The yield is good. The dye dyes polyester fibers in beautiful yellow tones.

   If you react with cyclopentylmethyl alcohol, you get a dye which has very similar coloring properties.



  <I> Example 2 </I> 1.1 parts of p-aminobenzoic acid cyclohexyl ester are mixed with 5.0 parts of water and 12.5 parts of concentrated hydrochloric acid and diazotized at 0 with 4 parts of sodium indtritol in 20 parts of water. The mixture is stirred for 11/2 hours and the excess nitrite is destroyed with sulfonic acid.



  Then 10 parts of 1- (2'-ethylphenyl) -3-methyl-5-pyrazo # ion are dissolved in 50 parts; Water and 21 dividers; 3011 / o sodium hydroxide solution. The mixture is cooled to 0-5 and the diazonium salt solution is slowly added. So then stir at 3-5 overnight. In the morning it is acidified with hydrochloric acid, and Idas reaction product is filtered off.

   The dye dyes polyester fibers in beautiful yellow shades with good fastness properties.



  If the diazonium salt is coupled with 1- (2'-chlorophenyl) -3-methyl-5-pyrazolone, a similarly good dye is obtained.



  <I> Example 3 </I> 11 parts of p-aminobenzoic acid cyclohexyl ester are diazotized according to the instructions given in Example 2. Then, 8.7 parts of 5-amino-3-methyl-1-phenyl-pyrazole are dissolved in 125 parts of water and 125 parts of glacial acetic acid and the mixture is cooled to 0-5. The diazonium salt solution is added. and stir for 1 hour at 0-5.

   The pH is then adjusted to 4-5 with sodium acetate and the mixture is stirred at 5 overnight. In the morning it is filtered off, washed neutral with water and the dye obtained is dried at 60-70 ° under reduced pressure. It dyes polyester fibers in beautiful yellow tones with good fastness properties.

 

Claims (1)

PATENT CLAIM Process for the production of, mono, azo dyes of the formula EMI0003.0120 wherein R1 is a hydrogen atom or an optionally substituted hydrocarbon radical, R2 is an optionally substituted, low molecular weight alkyl radical, a carboxylic acid ester group or an optionally: substituted carboxylic acid amide group, R3 is a hydroxyl or amino group, R4 is an optionally substituted alkylene radical, RS is a. optionally substituted; Cycloalkyl radical and n denote a small integer and the ring A hold further substituents ent. can, characterized in that one is a compound of the formula EMI0003.0165 wherein X is hydroxyl, halogen or the radical P.5- (R4) n =, 0- is diazotized, the so obtained diazonium compound with a pyrazole derivative of the formula EMI0003.0182 couples and the coupling product is esterified with an alcohol of the formula R5- (R4) n_1 OH (IV) if a compound of the formula (II) is used as the diazo component was used, where X is hydroxyl or halogen.