DE2636608A1 - Red dye for cellulosic fibres - comprises (1)-hydroxy-(3,6)-di-sulpho-(8)-acetamido-(2)-(3'-phosphono-pheny- l-azo)-naphthalene - Google Patents

Abstract

Novel 1-hydroxy-3:6-disulpho-8-acetamino-2-(3'-phosphonophenylazo)napht- halene and its salts are prepd. by reacting N-acetyl-H-acid with diazotised m-aminobenzene-phosphoric acid in the presence of suitable additives. Used as a red azo dyestuff for cellulose fibres, e.g. cotton, used pref. as the ammonium or acid ammonium salt. It may be used under acid conditions and together with suspension dyestuffs.

Description

Process for the production of new dyes

The invention relates to a process for the preparation of l-hydroxy-3,6-disulfo-8-acetamino-2- (3t-phosphonophenylazo) naphthalene and its salts, in particular the alkali metal and ammonium salts; the basic connection corresponds to the following formula: These new light red azo dyes have properties which are improved over those of known substances, ie good lightfastness and color strength; they are convenient to use in the dyeing industry, readily soluble in aqueous solutions (with or without surface-active agent (s), organic solvent (s) or the like) and easy to prepare.

For example, it has been found that the new dyes are lightfast and are more effective or more productive than normally used substances. So is for example versus a pound of the new dye for coloring a given amount of substrate (such as 100% cotton or another fiber) a larger amount, up to to about 1.65 pounds, of another high molecular weight dye required to make the to dye the same amount of material.

The dyes of the invention, although generally known as Dyes are useful, particularly useful for reactive dyeing, i.e., for a Process in which the dye reacts on the cellulose fibers of the Substrate is bound by means of a phosphoric ester bond, which in the presence of a Carbodiimides such as cyanamide is formed.

This process is described in detail in patent application P 25 05 497.1 , to which reference is hereby made in full.

Even if the acidic dye according to the invention is also in the form of the free Acid is used in the formulation, it can also be in the form of the alkali metal or ammonium salts can be produced and used. He is preferably in the Form of the free acid, particularly preferably in the form of ammonium or one acidic ammonium salt is used. Salts the dye with under pickling conditions volatile amines can also be used. The ammonium and acidic ammonium salts are formed simply by adding ammonium hydroxide to solutions of the dye made of the free acid. Corresponding are pH settings of the dyebath upwards preferably carried out with ammonia, less preferred with a volatile amine such as dimethylamine. pH adjustments are made downwards, if necessary, preferably with hydrochloric acid or another volatile under pickling conditions Acid.

The dye according to the invention in the form of the free acid is when it is used at a low pH value, as exemplified below, used in aqueous solution. At higher pH depends on the nature of the ammonium or Alkali metal salt of the dye in solution from the content of ammonia or alkali metal of the solution, measured by the pH. The ammonium salts are usually the tri or tetraammonium salts or mixtures thereof within those generally used pH range. Mixtures of ammonium and alkali metal salts can also be used will.

The compounds of the invention can generally be prepared thereby that N-acetyl-H-acid with diazotized m-aminobenzenephosphonic acid in the presence suitable additives is implemented. The production of N-acetyl-H-acid is in Fierz-David, "Fundamental Processes of Dye Chemistry", Interscience Publishers, 1949, p. 263 to 264. The general response of certain naphthol sulfonic acids with 3-aminobenzenephosphonic acid is described in Example 1 of US Pat. No. 3,220,550.

The method according to the invention is characterized in detail in the introduction mentioned type characterized in that to a solution of H-acid and an alkali metal carbonate Acetic anhydride in water was added dropwise with stirring, then alkali metal carbonate again added, heated to deacylate the hydroxyl group and the resulting solution Is ice-cooled that a m-aminophenylphosphonic acid and alkali carbonate containing aqueous solution mixed with an aqueous nitrite solution, cooled, concentrated in Added hydrochloric acid to ice and the resulting second solution at once to the first Solution of acetyl-H-acid given and is stirred, whereupon concentrated Hydrochloric acid was added to a pH of about 0.5, the solution was filtered and the precipitated one Solid washed with glacial acetic acid, dried and, if necessary, replaced by acidic ion exchange resin is further purified in aqueous alcoholic solution.

Example 1 175 g of H-acid (0.5 mol, purified by reprecipitation, commercially available Product), 30 g of sodium carbonate and 750 ml of water were mixed and dissolved to dissolve heated to 50 oC. 85 g (0.83 mol) of acetic anhydride were added dropwise over 15 minutes, and the solution was then stirred at 50 ° C. for 1 h. 75 g of sodium carbonate were then added added and the solution was heated to 95 ° C. for 1 h to avoid any acylation of the hydroxyl group to undo. The solution was then chilled in ice.

86.5 g (0.5 mol) of m-aminophenylphosphonic acid and 53 g (0.5 mol) of sodium carbonate were dissolved in 500 ml of water. 37 g (0.54 mol) of sodium nitrite in 100 ml of water were added and the 0 solution cooled to 10.degree. The solution became 125 ml more concentrated Hydrochloric acid and 500 g of ice were added. This solution became at once the solution of acetyl-H-acid was added and the resulting solution was stirred for 1 hour. Then 500 ml was concentrated Hydrochloric acid was added (pH = 0.5) and the solution was filtered. The precipitated solid was washed with glacial acetic acid and dried under vacuum at 50.degree.

The further purification to the free acid was carried out by dissolving the dye in aqueous methanol and passing the solution through an acidic ion exchange resin. Removal of the solvent resulted in a dye which, after titration, was a tetrabasic acid with a purity of> 95%, making that given above Structure was confirmed.

As a further analytical method, the free acid in solution became the tripotassium salt implemented and the solution concentrated to dryness, the potassium salt heptahydrate the empirical formula C18H 13011N3S2PK3 2 7H20.

Result of the elemental analysis: calc.: C 27.5 N 5.4 S 8.1 P 3.9 H20 16.0 molecular weight 785 found. : C 26.9 N 5.8 S 7.7 P 3.5 H 2 O 15.5 Molecular Weight 789 Example 2 A paste-like printing ink was prepared using 0.05 percent by weight of the dye of the formula and 0.15 percent by weight of a blue dye of the structure This dye is prepared by reacting bromamic acid with o-amino-p-xylylenediphosphonic acid, as described in Example 25 of DT-OS 2,505,497.

The printing paste also contained 0.2 percent by weight of a wetting agent (Igepal CO-710, nonylphenoxypoly (ethyleneoxy) ethanol with 10 to 11 ethyleneoxy units), 0.1 percent by weight (NH4) 2HPO4, 3.0 percent by weight dicyandiamide, 1.0 percent by weight Sodium alginate, 33.0 percent by weight of a 70% Varsol emulsion, the remainder being water. The resulting printing paste was adjusted to a pH of 8.6 with ammonium hydroxide.

The printing paste produced in this way was applied to 100% cotton-2 fabric screen printed with a print run of around 6 g / m2 (5 g / sq.yd.) (around 100% average print run). The fabric was dried and turned into a printed cotton fabric at 204 ° C. for 60 seconds fixed with a good color fixation.

In Examples 3 to 5 below, all percentages relate to on the weight of the fleet.

Example 3 A dye liquor with the following ingredients was made manufactured: 1.0% red dye of example 1 3.0% H3P04 (85 %) 8.0% Cyanamid AC-50 (50%) 2.0% Carbowax 350 0.25% Igepal CO-710 pH 1.5 Die The above liquor was padded to 100% cotton with 70% absorption 104 ° C and hardened for 60 sec at about 200 ° C. The cloth was rinsed at the same time practically no color was removed.

Example 4 A liquor with the following ingredients was prepared: 0.5% red dye of Example 1 5.0% cyanamide AC-50 (50%) 0.5% Igepal CO-710 0.3% H3PO4 (85%) pH adjusted to 5 with NH4OH. This liquor was made of 100% cotton padded, steamed for 1 min at 104 ° C and then cured for 45 sec at about 200 ° C. When the cloth is boiling with 1.7 g / l anhydrous soda and 1.5 g / l Synthrapol SP was boiled for 2 min, 80% fixation was achieved. The fixation is here defined as the percentage of the color remaining on the fabric after boiling, based on the color as it comes out of the curing oven, with both color measurements were done on a Beckman DBG spectrophotometer.

Example 5 The following liquor was produced: 2.0 % red dye of example 1 4.0% dicyandiamide 0.1% Igepal C0-710 0.125% H3P04 (85%) pH 5 This bath was made on a 50/50 blend of polyester (T54) / cotton padded on at 60% absorption, pre-dried by IR and cured for 75 sec at 204 ° C. After boiling out as in Example 4, the color fixation was 70%.

As noted above, the dyes of the present invention are unusual effective and abundant, by which is meant the dye yield per unit weight of dye exceptional for a dye that is washable on cellulose fabrics and yarns is. The extraordinary effectiveness is due to the fact that the dyes lead by themselves to intense light red colorations, in connection with the fact that that their molecular weight is very low compared to the direct dyes with large molecules that are absorbed directly onto cellulose materials. Consequently delivers each molecule, i.e.

any low molecular weight of these has a high color yield a weight / weight basis.

The low molecular weight, or in other words, the general The dyes according to the invention offer simplicity and smallness of the molecule yet another benefit. Especially when a dye passes through to a substrate chemical conversion is permanently fixed or bound, it is very desirable that any portion of the dye that was not reactively bound during the rinse process is easily washed out so as to lead to a light washout and subsequent To reduce "washed out" during use. In the case of the dyes according to the invention the same phosphonic acid group that is a reactive site also serves as a highly water-solubilizing group that removes all not Supported fixed dye molecules, thereby effective removal of unfixed Dye is ensured during the rinsing process and the subsequent pulling out Washout reduced or even eliminated during use by the wearer will. The dyes according to the invention are washed out more easily during the rinsing process than any red dye currently used in commercial continuous dyeing is used.

The acetyl group is introduced as the smallest group in the dyes, which is able to reduce the inherent photosensitivity of H-acid dyes to overcome.

Other groups also lead to lightfastness, but not as effectively like the acetyl group. In other words, the acetyl group leads to lightfastness in connection with the lowest possible effect on the high red color intensity pro Weight unit of the dyes according to the invention.

The dyes according to the invention have clear advantages in comparison to conventional reactive dyes that are used under strongly alkaline conditions by mostly using them under acidic conditions and so on can be used together with suspension dyes in the same dye liquor can. Alkaline conditions lead to flocculation of the majority of suspension dyes, what the possibilities for simultaneous dyeing of polyester and cotton with Suspension and conventional reactive dyes are drastically limited. In contrast to this have the acidic fixing conditions, as they are in accordance with the phosphonic dyes the invention applied, no adverse effect on the suspension dyes, and the two kinds of dyes can be used together with each other without difficulty be used.

Claims (2)

PATENT CLAIMS 1. Process for the preparation of 1-hydroxy-3,6-disulfo-8-acetamino-2- (3'-phosphonophenylazo) naphthalene and its salts, characterized in that N-acetyl-H-acid with diazotized m-aminobenzenephosphonic acid is reacted in the presence of suitable additives. 2. The method according to claim 1, characterized in that to one Solution of H-acid and an alkali metal carbonate in water, acetic anhydride, with stirring added dropwise, then again added alkali metal carbonate to deacylate the hydroxyl group heated and the resulting solution is ice-cooled that a m-aminophenylphosphonic acid and aqueous solution containing alkali carbonate with an aqueous nitrite solution added, cooled, poured into concentrated hydrochloric acid on ice and the resulting second solution added at once to the first solution of acetyl-H-acid and stirred is then added concentrated hydrochloric acid to a pH of about 0.5, the Filtered solution, washed the precipitated solid with glacial acetic acid, dried and optionally by acidic ion exchange resin in an aqueous-alcoholic solution is further cleaned.