DE2619320A1 - PROCESS FOR THE PRODUCTION OF EASILY REMOVABLE COLORS - Google Patents

Description

concerning:

" Process for the production of easily removable dyes"

The invention relates to dyes that are unstable in remote or so volatile in that they can easily be made so that p ₃ ^- blank efärbten materials, for example textiles, wash out. The dyes to be produced according to the invention are those which contain ethoxylated nitrogen groups.

Ausv. ^: Chb; a-e bxv ;. lexer.!, c .i.i'ei'uij.'ii'C dyes v; earth often used for coloring "code" fabrics during production and / or during finishing to identify certain synthetic or natural fibers, The fibers can be colored, for example, before they are spun into yarns and then in Knotting or weaving processes are used to ensure that there are no unwanted fibers or yarns are present «At the last the stains are then washed out or otherwise disintegrated

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BATH ORIGINAL

before the product is sold. Such fickle dyes must be useful in order to be useful be easy to remove even after exposure to extreme conditions, which possibly prevail during the production and finishing of the textile in question. This volatility affects the dyes in every way of textile. On the other hand, however, it is essential that the dyes have good color stability have ^ so that they are not already exposed to the action of heat or light, for example when processing the Fabric, fade or discolor.

Easily removable dyes which are widely used in practice are the polyethyleneoxy dyes described in U.S. Patent 3,157,633. Of these, combinations of a dye radical and one or more polyethyleneoxy groups are preferred. Azo and anthraquinone groups, inter alia, are mentioned as dye radicals in the patent. A typical process for the preparation of such dyes consists in forming a paranitroso derivative from an aromatic polyethyleneoxy-mitro compound by treating it with sodium nitrite at a temperature below room temperature and a very low pH. The nitrous derivative is then mixed with a metal and an acid, for example with zinc and hydrochloric acid _? reduced to the paranmino derivative. After filtering off the metal from the solution, the amino derivative is then diaotated with additional sodium nitrite at a low temperature, whereupon the diasonium is coupled with an aromatic hydroxy compound at a highly alkaline pH value. The resulting mixture is neutralized and filtered again to remove any metal residue «The implementation

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All of these individual steps took several days, with the reaction mixtures being processed during the processing need to be cooled to a greater or lesser extent. In addition, the entire process must be carried out in vessels which ge ^ en prolonged contact with strongly acidic Mixtures are resistant.

Another problem is the removal of the metal used in making the dyes. Although the intermediate and end products are filtered, metal is then always present in the piltrates, which can lead to difficulties for the manufacturer in terms of environmental pollution. Stay there are traces of metal in the dye itself the risk of discoloration on the fabric and, moreover, there are difficulties in draining off the washing water that occurs when the dye is washed out.

To reduce Mitroso derivatives to the corresponding amine, one can also use catalytic hydrogenation processes, but must then be pressure-safe Facilities worked i ^ earth and also exist still difficulties in removing the specialty catalysts used.

It has also been suggested (see J.11. L'edder et al. in J.Chem.Soc., 4003 (1957) and later publications) , when introducing a diazonium group in various aromatic compounds in an organic solvent or in a mixed one Medium of solvent and water to work. However, because when using solvent systems solvent recovery involves considerable costs, these proposals could prove to be worthwhile

not enforce in practice. Further proposals to introduce the liazonium group in an aqueous medium, remained without practical success due to the inadequate yield.

Surprisingly _, according to the invention, a process for the preparation of easily removable polyethyleneoxy dyes in very good yield is proposed, in which operation is carried out in aqueous riedium without the use of metals or strongly acidic solutions the dyes can be produced in a considerably shorter time than before.

The inventive method for the preparation of easily removable dyes is that treating an aqueous solution of an aromatic Polyäthylenoxyverbinduiig at a pH value between about 2 lind 5 ^mi "k an excess of nitrous acid so that directly forms a diazonium salt, and daii one the resulting diazonium salt is then reacted with a nucleophilic compound in order to couple the salt to this compound and thus to form an unstable, ie easily washable, dye.

According to the invention, generally speaking, a substituted one is used as the aromatic polyethyleneoxy compound or unsubstituted amine, phenol, etc., that between 10 and 500, preferably between about Contains 20 and 250 iithylenoxy units. With increasing

-oxy number of Athyleiyelnheiten decreases the coloring power of the unstable dyes made from it inevitably away. On the other hand, however, the dyes are with

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with an increasing number of ethyleneoxy units, it becomes more and more difficult to remove from sensitive fibers.

In the aromatic polyethyleneoxy compound the ' aromatic group, for example a substituted or unsubstituted benzene, naphthalene or anthracene group be. Examples include: phenol, resorcinol, aniline, naphthol, naphthylamine, toluidine and the like.

The reaction of the aromatic polyethyleneoxy compounds with excess nitrous acid is, as already mentioned, carried out at a pH between about 2 and 5. The conversion is expediently carried out at normal temperature, although lower and higher temperatures can also be used. The nitrous acid is expediently formed in situ, including a combination of a nitrite, such as sodium nitrite, with a strong acid such as hydrochloric acid, sulfuric acid and the like. Used. During the reaction, the nitrous acid must be present in excess, preferably is this excess is about 6 to 9 moles of nitrous acid per mole of aromatic compound.

Surprisingly, when the aromatic polyethyleneoxy compound is reacted with excess nitrous acid, the diazonium salt is formed immediately, which is then coupled with a nucleophilic compound so that the easily removable dye is formed * Serves as a nucleophilic compound _? generally speaking, _s a dye coupler that is preferably a substituted aromatic compound. Examples include _e a _s .: phenols resorcinols, naphthols, naphthylamines ,, Aniline _s acetylacetones, acetylacetonates _P Acetoacetanilides, malonic acid and its esters, j ^ -Methylene-

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- 6 acids, esters, aldehydes and ketones and the like.

The Kuppluiigsreaktion is zwockmäßigerweise "performed at a '.Temperature which is below K orm al temperature, ö ^{e <i} can ^ocn nian also" operate at Hardly temperature or higher, the coupling is carried out under alkaline conditions, is obtained under generally Better yields at room temperature, since the resulting mazonium salt is relatively unstable under strongly alkaline conditions.

The invention is based on the examples in which parts and 1% mean parts by weight or (lew.-70, explained in more detail.

Manufacturing process A

ifie Preparation of p-Diazoiiiumsalzes of Polyäthylenoxyaniliii v / ie carried out as follows: In a equipped with a stirrer Gefäii at room temperature under stirring, to 124 parts Polyäthylenoxyanilin (65 "/ o in V / ater) V with 1OÜ ethyl enoxygrupp en ^> O parts / ater was added. Then 1R parts are further stirring solid! sodium nitrate was added and stirring until the dissolution of sodium nitrate continued s' to adjust the pH-V / ert the mixture to etv / a ^ ₅ O adjust, with stirring 10 parts of hydrochloric acid (20 ° Baume) were added and the whole was stirred for a further 2 hours.

At this stage the reaction mixture contains a considerable excess of nitrous acid or not must be destroyed if the subsequent coupling reaction is carried out under alkaline conditions will. However, if the coupling takes place under acidic conditions,

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like "when coupling to a primary or secondary tertiary amine, so the excess of nitrous oxide Acid removed. This is preferably done by placing the reaction mixture under vacuum and the solution then removes nitrous oxide. To the distance the nitrogen oxides can also be air or nitrogen through ' blow the mixture through and also can optionally the excess nitrous acid also by adding a sufficient amount of sulfamic acid, Urea or the like. be bound.

The actual yield of the diazonium salt which forms under these conditions can be demonstrated by determining the molecular absorption coefficient of the compound. It has surprisingly been found that the extinction coefficient of the diazonium salt obtained in this way is at least the same and in many cases higher than that of the same compound when this has been prepared with the aid of the known reduction-diazotization process. Typical molecular extinction coefficients of the diazonium compound are between 55,000 and ~ 1, B, 000, which suggests an essentially quantitative yield.

Manufacturing process B

To 346 parts of a 65 / yigen aqueous solution of Polyäthylenoxyanilin with 100 Ethylenoxygruppen be 25 parts of sodium nitrite in a suitable reaction vessel, dissolved in 70 parts of water, added. With vigorous stirring, 8.5 Parts by volume of sulfuric acid are added, whereupon the reactor content is stirred for a further 90 minutes. The pH is

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then slightly below 2. Now is using an effective Vacuum pump with continued stirring in the A vacuum is carefully created in the reactor, the nitrogen oxides escaping with considerable foaming from the mixture, outside. Hear the development from colored geese up, so is; the reaction mixture ready for coupling.

Manufacturing process G up to 1 ''

It was made according to manufacturing modes A and B above worked, but the Polyätirylenoxyanilin was replaced by Polyäthylenoxy-m-toluidine and Polyäthyleiioxy-m-chloralaniline.

Manufacturing types G to ΙΊ

Production methods A and B were used, but the number of ethyleneoxy groups in the Polyathyleiioxyari.ilin was changed to 20, 55 ■> 5 ^ and 20Ü.

Other types of manufacture

For the following production types, the work trip corresponds to that of the previous production types, However, the polyethyleneoxyaniline used to form the Diazoniumsalzlösung.es through the following compounds are replaced in stoichiometric ranks was: Polyäthylenoxyphenol, Polyäthylenoxyresorcin, Polyäthylenoxyanisol, Polyäthylenoxy-manisidin, Polyäthylenoxy-m-phenylenediamine, Polyäthylenoxy-aminophenol, Polyathylenoxydiphenylamine, Polyäthylenoxy-p-aminodiphenylamin, Polyäthylenoxynaphthämmin, Polyäthylenoxynaphthylenediamine and Poly-

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ethylene oxynaphthoi.
Example 1_

7.4 parts of chromotropic acid (1ÜÜ> j), 8 parts .Natriumhydroxid (50 / ^) and JO parts of water are "stirred together at room temperature in a reactor until the chromotropic acid is dissolved. The solution is then according to the ^ Preparation method A "prepared hiazonium salt mixture was slowly added and the mixture was then stirred vigorously for j> 0 min, whereby a pH value; is maintained above 12, then add sufficient additional hydrochloric acid to bring the pH to about 7 _? 5 goes back.

With the "blue" dye produced in this way Polyester yarns are dyed before they are used to produce knitted fabrics. From the finished The dye can be washed in a one percent detergent solution ("Tide" detergent J. be easily and completely removed.

example 2

To a vigorously stirred mixture of 1000 parts Jüis "and 30 parts of sodium hydroxide (50" / o'j is added 2j5,5 parts chromotropic acid (75.6; Ό active) and stir until further, until a clear solution is achieved then. the diazonium compound obtained in accordance with preparation method B is added in a steady stream over the course of 1 minute with continued vigorous stirring The molecular extinction coefficient of the compound so prepared is about ^ 5,000.

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animal blue fruit ox'i "is similar to the one according to Example 1, can be removed very easily and completely from yarns dyed with it.

Examples -j to β

The procedure was as in Example Λ and 2, but using equimolar hens of Η-acid, Chicago acid or K-acid. The blue dyes obtained corresponded to those from Examples 1 and 2 in terms of ease of removal.

To a mixture of 5 parts of water and 15 parts of polyethylene oxytoluidine (65 %) with 100 ethyleneoxy groups, the diazonium salt obtained according to method of preparation A is added at room temperature with vigorous stirring and the pH value is adjusted to 4 to 4 with iviatrium acetate , 5 'is set. Stirring is continued until all of the diazonium salt has been consumed.

Wan receives a yellow color, which is the same Same as the blue dye after the preceding ones Examples easily and completely made of a polyester fabric remove loud.

Examples 10 to 1 '/

Iari works analogously to Examples Λ and 2, but using an equiidolar proportion of Chicago acid and the ^{mixtures prepared according to C to l · "1} are coupled to the nucleophilic compound.

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- ΛΛ -

receives blue dyes, which, as above, easily and completely washed out of polyester fabrics ".

Example 18.

Haη works according to Example 2, but an equiinolar amount of barbituric acid used, which is added to the diazonium compound obtained according to B. clutch.

An orange-red dye is obtained with which one dyes a polyester yarn before texturing it. In this case too, the dye can easily and completely with a one percent ash solution be washed out, either already from the yarn or from a knitted fabric made with it.

l) The polyethyleneoxyamines used in the preceding examples can be prepared by bubbling ethylene oxide through a liquid compound, for example m-l'oluidine, aniline, etc., in the presence of a small amount of sodium catalyst. As far as possible, the compound should remain liquid during the atfoxylation. With compounds that are to 25O ⁰ C solid at the reaction temperature of about 50 or decompose at the higher temperatures, one can perform · reaction in an inert solvent.

As can be seen, the invention provides a novel method of making easily removable Polyethyleneoxy dyes from the p-J) iazo derivatives of aromatic Polyäthylenoxyamxnen or -phenolen in very

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good yield provided, with neither iietalle nor strongly acidic solutions being used. As a result, can be with the help of the invention Process such easily removable i'arboffe Produce in a much shorter time without having to cool the reaction mixture and / or filter

Of course, the method according to the invention can be modified in various ways without exceeding the scope of protection. Thus , for example, a wide variety of polyethyleneoxy compounds with different degrees of epoxylation and a large number of nucleophilic compounds can be used and the examples given serve only to illustrate the invention.

rt iAJM ÜPHÜ CHE:

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Claims (1)

Jr A ΐ ti 1 ·) 1 'A ii ο P H üCü j, (T) Process for the manufacture of easily removable Dyes, characterized in that an aqueous solution of an aromatic polyethyleneoxy compound is used at a pH between about 2 and 5 with excess nitrous acid immediately to one Diazoniumsalζ converts and the diazonium salt with a nucleophilic compound couples to the easily removable dye. (2) Process according to Claim 1, characterized in that one is used to form the diazonium salt at least about 6 moles of o-petroleum acid are used for each aromatic compound. (3) Method according to claim 1 or 2, characterized in that one dart after coupling of the diazonium salt with the nucleophilic compound that Reaction mixture neutralized. (4) The method according to claim 1, 2 or 3, characterized characterized by the formation of the Performs diazonium salt at ambient temperature or at a temperature below that. (5) Method according to one of the preceding claims, characterized in that as aromatic polyethyleneoxy compound is a compound having at least 10, preferably 10 to 500 and in particular 20 to 250 ethyleneoxy units are used. 809845/0988 ORIGINAL INSPECTED (6) Process according to one of the preceding claims, characterized in that the aromatic polyethyleneoxy compound is a polyethyleneoxy compound in which the aromatic group is a substituted or unsubstituted iüiiin or phenol. (7) Vr .. method according to one of the preceding claims, characterized in that one as nucleophilic compound used an i'arbstoii'kuppler. (8) Method according to one of the preceding claims, characterized in that as nucleophilic compound an aromatic compound, especially a substituted or unsubstituted one Phenol or uaphthol compound used. 609845/0988