DE19615898A1 - Dyeing of fibres with amino group-containing dyes to give high wet fastness - Google Patents

Abstract

The dyeing of fibres containing OH and/or NH groups with a dye containing one or more primary or secondary amino groups is effected in presence of a water-dispersible polyisocyanate. The fibres are preferably treated with the polyisocyanate during or after the dyeing process.

Description

In order to migrate textiles from OH and / or NH group-containing fibers, to dye sweat and washable, you generally use the so-called called reactive dyes. These dyes contain reactive groups that are under Coloring conditions with the OH and / or NH groups of the fiber covalent bin received. The most common reactive groups include N-heterocycles, which contain chlorine and / or fluorine atoms as leaving groups, by their Cleavage under alkaline reaction conditions a covalent bond of Colorant is made to the fiber. Vinyl sulfones are also commonly used or sulfuric acid ester of β-hydroxyethyl sulfone, which under alkaline loading saponify conditions and form vinyl sulfone, which then additive with the hydroxyl groups of the cellulose fiber reacts. Isothiocyanate groups are reactive hooks also known (see, e.g., US 2,937,186). From the use of Isocyanate groups are used as reactive hooks because of their low hydrolysis resistance discouraged (cf. Angew. Chem. 73 (1961), 125ff). A disadvantage of Dyeing with reactive dyes is the relatively high cost of dyeing as well poorer handling of the highly reactive dyes.

Direct dyes that do not contain reactive groups and because of physical Processes bound to the fiber are also suitable for dyeing Cellulose and its blends with synthetic fibers, being the unproblematic Application, high economy and good lightfastness of these dyes in the Stand in the foreground. The wet fastness properties of those with direct dyes dyed textiles mostly to be desired. An improvement in fastness can with these dyes by post-treatment, for. B. with cationic Aids. The way these aids work is based on the one hand on a decrease in the hydrophilicity of the dye due to ion pairing and on the other hand, gluing the pores of the textile fibers.

From CH-560 802 is already a method for the after-treatment with Disper Sions dyes known textile materials with isocyanate releasers known. This Isocyanate splitters are crosslinking products of isocyanates with e.g. B. alcohols, Phenols, thiols, carboxylic acids which decompose under the influence of heat and Release isocyanates. The dyeing processes known from the prior art are not satisfactory in terms of all the requirements placed on them.

A new dyeing process has now been found which is easy to handle and economical direct dyes served and thereby achieved dyeings whose Fastness properties are comparable to those of reactive dyes.

The present invention relates to a method for dyeing OH and / or Fibers containing NH groups with dyes having at least one primary or secondary amino group have what in the presence of at least one water-dispersible polyisocyanate.

The colorations achieved with the process according to the invention are noticeable characterized by an excellent wet fastness.

The fibers to be dyed with the method according to the invention are preferably cellulose or wool or their mixtures or any Mixtures of the types of fibers mentioned with other fibers such. B. polyamide, Polyester, etc.

The term "water-dispersible" in connection with the ver according to the invention Turning polyisocyanates means that the polyisocyanates in a concentration tion of <0.1 to 99.5% by weight, preferably 0.1 to 10% by weight with water result in finely divided dispersions.

Mixtures of Polyiso can also be used as water-dispersible polyisocyanates cyanates that are not self-dispersible, with external, ionic or not ionic emulsifiers are used.

In a preferred embodiment of the method according to the invention however, self-dispersing polyisocyanates are used, for example

• (I) water-dispersible nonionic polyisocyanate mixtures from polyiso cyanates and polyether-modified polyisocyanates with cycloaliphatic and / or araliphatic and / or aliphatic isocyanate groups, which ent in the main chain, if appropriate, ester and / or amide groups hold,  
• (II) polyisocyanate mixtures of polyisocyanates and carboxylate group modifi graced polyisocyanates with cycloaliphatic and / or aliphatic bound NEN isocyanate groups or
• (III) water-dispersible, nonionic polyisocyanates with aromatically bound NEN isocyanate groups or mixtures of such polyisocyanates.

Water-dispersible polyisocyanate mixtures (I) are preferably used. With

• a) an average NCO functionality of 1.8 to 4.2, preferably 2.1 to 4.2,
• b) a content of aliphatic and / or cycloaliphatic iso cyanate groups (calculated as NCO, molecular weight = 42) from 3.0 to 21.5% by weight, based on the polyisocyanate mixture (I),
• c) a content of ethylene arranged within polyether chains oxide units (calculated as C₂H₄O, molecular weight = 44) from 2 to 20 wt .-%, based on polyisocyanate mixture (I), the polyether chains have a statistical average of 5 to 70 ethylene oxide units, and
• d) an ester group content of 0 to 300 mol% and / or a content of amide groups from 0 to 300 mol%, based on the ent in the mixture hold free NCO groups.

The water-dispersible polyisocyanate mixtures (I) can be known Way by reacting a polyisocyanate component A) with a (middle) NCO functionality from 1.9 to 4.4, preferably 2.0 to 4.3, consisting of at least one polyisocyanate with exclusively aliphatic and / or cycloaliphatic isocyanate groups and optionally with a mono- or polyvalent, on average from 5.0 to 70 ethylene oxide units having polyalkylene oxide polyether alcohol B) while maintaining a NCO / OH equivalent ratio of at least 2: 1, generally from 4: 1 to approx. 1000: 1, the rest being the nature and proportions of the above Output components are chosen so that the resulting implementation tion products correspond to the conditions mentioned under a) to d) above.  

The polyisocyanate components A) are those with uretdione and / or isocyanurate, urethane and / or allophanate, biuret or oxadiazinetrione structure, as for example in DE-A-16 70 666, DE-A-37 00 209 and DE-A- 39 00 053 or in EP-A-336 205 and EP-A-339 396 are described by Prepolymerization or other modification easier (preferably ali phatic and / or cycloaliphatic) diisocyanates can be prepared.

Suitable diisocyanates for the production of such polyisocyanate components A) are basically those in the molecular weight range 140 to 400 with aliphatic and / or cycloaliphatically bound isocyanate groups, such as. B. 1,4-Diisocya natobutane, 1,6-diisocyanatohexane, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1,6-diisocyanatohexane, 1,10-diisocyanatodecane, 1,3- and 1,4- Diisocyanatocyclohexane, 1-isocyanato-3,3,5-trimethyi-5-isocyanatomethylcyclo hexane (isophorone diisocyanate) and 4,4'-diisocyanatodicydohexylmethane or belie bige mixtures of such diisocyanates by trimerization to trisisocyanato isocyanurate or biuretization or allophanatization and subsequent Thin layers are free of monomeric diisocyanates.

Such isocyanate mixtures can be used, those for the better Emulsifiability in water either contained in the mixture of emulsifiers or in which the emulsifiability by reaction of a part (5-50%, preferably 8- 30%) of the NCO groups with compounds which are capable of salt formation (e.g. dimethylolpropionic acid or N, N-dimethylethanolamine (e.g. according to DE- A 43 19 571 or DE-A 44 18 836)) and / or hydrophilic, preferably monofunctional polyethers (according to DE-A 42 11 480) was brought about.

If you want to have hydrolyzable compounds, you can use them proportionately or alone Isocyanates containing esters and / or amide groups can be used by Reaction of isocyanates with components containing OH groups after known methods can be obtained.

As isocyanates are diisocyanates such as. B. 1,4-diisocyanatobutane, 1,6- Diisocyanatohexane, 1,5-diisocyanato, 2,2-dimethylpentane, 2,2,4- or 2,4,4-tri methyl-1,6-diisocyanatohexane, 1,10-diisocyanate decane, 1,3- and 1,4-diisocyanato cyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (Iso phorone diisocyanate), 4,4'-diisocyanatodicydohexylmethane and any mixtures such diisocyanates. In principle, aromatic isocyanates, e.g. B.  Toluene diisocyanates, 4,4-diisocyanato-di-phenylmethane are used: because whose poor lightfastness and high reactivity to water are however, the aliphatic isocyanates are preferred. Proportionally can within the specified parameters also polyisocyanates by modification of the above mentioned diisocyanates, or mixtures thereof according to literature Process with uretdione, urethane, isocyanurate, biuret, or allophonate groups can also be used.

As OH-containing compounds with esters and / or amide groups Suitable products that have on average at least 2 OH groups and on average have at least one ester and / or amide group.

Are suitable for. B. short-chain polyester from dicarboxylic acids, and dicarbon acid esters with monofunctional alcohols or phenols or Dicar bonic anhydrides with diols and / or trilones.

The following may be mentioned as dicarboxylic acids or dicarboxylic acid derivatives: carbonic acid dimethyl ester, diethyl ester, diphenyl ester, ethylene glycol carbonate, Propylene glycol carbonate, oxalic acid, malonic acid diester, amber, glutaric, Maleic acid and its resulting anhydrides, adipic, sebacic, (optionally hydrogenated) phthalic, hydroxymono or dicarboxylic acids (optionally in the form of internal esters (lactones)), such as glycol, wine, milk, Citric, hydroxycapronic, as well as hydroxybutter or ricinoleic acid.

As diols such. B. the technically widely available, ethane, propane (1,2 or 1,3-), isomeric butane, pentane, hexane etc. diols, furthermore containing ether groups Oligo- or polymer of ethylene and propylene glycol suitable. Cycloaliphatic or aromatic diols are mentioned - but are because of high viscosity of the esters is not preferred. Suitable triplets are, for example Glycerin, trimethylolpropane.

Polyesters are formed by condensation of the acids and / or their esters with monofunctional alcohols and / or the anhydrides of the acids with the diols or triplets listed obtained by known methods. By Use of the OH compounds in excess and subsequent extraction with Water or by cruciform distillation can have a narrow molecular weight distribution and thus producing a low viscosity and a low content of non-ester  load-bearing components can be achieved. The ring opening is also very suitable Transesterification of lactomes (e.g. butyro-valero or caprolactone). This transesterification can optionally be carried out using the measures mentioned above be coupled.

Particularly suitable compounds containing OH groups are represented by Reaction of a di- or hydroxy-carboxylic acid with alkylene oxide obtained Defined, low molecular weight ester diols are formed in a simple manner.

OH compounds containing amide groups can be obtained from the acids mentioned or their esters (lactones) by reaction with hydroxyamines, the one secondary amino group such as B. adducts of ethyl or propylene oxide Mono-alkylamine (methyl, ethylene, tc. Amine) contain.

This reaction is particularly suitable because of the selectivity of the Amino groups leads to predominantly defined compounds. The middle ones Molecular weights of the OH compounds according to the invention are 148-2000, preferably 148-1000, particularly preferably 148-500.

To prepare the isocyanate, NCO-containing compounds with OH containing component in the NCO-OH ratio of 1.3-20, preferably 1.5-10 used.

At NCO / OH <1.5 ratios one remains - on the structure of the isocyanate dependent proportion of unreacted isocyanate. From industrial hygiene Reasons should these free isocyanates z. B. removed by thin film distillation (In this case, even a high NCO / OH ratio is preferred because then viscosity-increasing chain extension reactions are largely suppressed will.)

The water-dispersible poly used in the process according to the invention Isocyanates can be used to facilitate incorporation into the aqueous phase if necessary, dissolved in a solvent inert to isocyanate groups be used. Suitable solvents are e.g. B. ethyl acetate, butyl acetate, Ethylene glycol monomethyl or ethyl ether acetate, 1-methoxypropyl-2-acetate, 2- Butanone, 4-methyl-2-pentanone, cyclohexanone, toluene, or their mixtures, however also solvents such as propylene glycol diacetate, diethylene glycol dimethyl ether,  Diethylene glycol ethyl and butyl ether acetate, N-methylpyrrolidone and N- Methylcaprolactam, or mixtures of such solvents. These solvents will be the water-dispersible polyisocyanates, optionally in amounts of up to 90% by weight, preferably at most 50% by weight and particularly preferably at most at least 20% by weight, based on the solution formed. Most notably however, the use of solvent-free, water-dispersible poly is preferred isocyanates.

The water-dispersible polyisocyanates come in the Ver drive in amounts of 0.005 to 50% by weight, preferably 1 to 10% by weight, based on textile substrate used, preferably they are used in cold processing because processes are used, i.e. they are incorporated together with the dye puts. Before using the polyisocyanates, they can be used in 1-4 times the amount Water, based on polyisocyanate, predispersed. The Use of component (I) processing times of up to 24 hours. At Use of water-dispersible aromatic polyisocyanates (III) are the ver Working times significantly shorter due to the higher reactivity to water zer and are generally less than 8 hours.

The water-dispersible polyisocyanates to be used according to the invention can used at the processing temperatures usual in the textile industry will. Depending on the temperature, there may be different processing times ten for the products to be used according to the invention. So you have for example with polyisocyanate according to DE-A-42 11 480 Ex. A) at 23-25 ° C. relatively long processing times, because at this temperature after 5 Hours before about 60% isocyanate groups. At a temperature of 35 ° C are still about 50% after 5 hours and at 50 ° C for polyisocyanate A) 3 hours before 33% isocyanate groups. The processing time at a be The right temperature can be selected by choosing a suitable one according to the invention applicable polyisocyanate are affected.

The pH of the dyebath should be used when adding the invention end polyisocyanates preferably between 5 and 8.5, especially in neutra len range. PH values below 4 or above 9 should be avoided.

Dyes suitable for carrying out the process according to the invention have at least one primary or secondary acylatable amino group and  are well known. A substantive character of the dyes is advantageous d. H. Direct dyes, for example those for dyeing cotton and paper with corresponding amino functions are preferred, such as. B. the two Black dyes of structures (I) and (II)

Also preferred are so-called color bases (dye chromophores) of the general formula [FB] - (H) _1-4 , which are used as acylatable intermediates in reactive or direct dye synthesis and which likewise have substantive properties. Examples of color bases of the formula [FB] - (H) _1-4 are the following structures (III) to (XII)

Dyes containing sulfo groups and triazine groups are particularly preferred basic primary and secondary amino groups, as described in DE-A- 29 15 323, DE-A-30 30 916, DE-A-33 13 965, DE-A-34 40 777 and DE-A- 36 25 576 are described as paper dyes and in non-ionized form of the formula (XIII)

correspond to what
FB for the rest of a dye chromophore, such as. B. contained in structures (III) to (XII),
Z₁ for a bridge member -CO-, -SO₂- or

Z₂ for a pontic

the bridge member Z₁ or Z₂ is bound to an N atom in FB,
Y represents Cl, OH, NH₂ or an aliphatic or aromatic amine radical, optionally also for X,
X for a basic group preferably -NR²-Q-NR³R⁴,

or
a rest of the formula

wherein the aromatic rings may have additional substituents such as SO₃H, CO₂H, CH₃, C₂H₅, Cl, Br, CH₃O, C₂H₅O,
Q for linear or branched C₂-C₆ alkylene,
R² is hydrogen or C₁-C₄-alkyl,
R³ and R⁴ independently of one another are hydrogen-unsubstituted C₁-C₆-alkyl, C₂-C₆-alkyl substituted by hydroxyl or cyano, phenyl-C₁-C₃-alkyl, the phenyl radical of which by up to three substituents from the series chlorine, C₁- C₄- Alkyl and C₁-C₄-alkoxy may be substituted, Cub-C₆-cycloalkyl which is unsubstituted or substituted by up to three C₁-C₄-alkyl groups, or
R³ and R⁴ together with the N atom bonded to them form a 5- or 6-membered, optionally a further heteroatom (from the series O, N, S) including a saturated ring,
m for an integer from 1 to 4,
n for 0 or an integer from 1 to 4 and
p represents 0 or an integer from 1 to 3,
where the conditions regarding the number of basic groups X present

n + 2p <m + 1 and n + p ≠ 0

be valid,
and can be present as an inner salt.

Accordingly, dyes of the formulas (XIV) to (XXIII) are particularly preferred

The method according to the invention is usually carried out after the dyeing process used for direct dyes. That according to the invention Polyisocyanate to be added can be added to the dyeing liquor during the dyeing process are set or preferably in a post-treatment step the ge dyed textile can be added. This aftertreatment of the dyed textile by a block application of those to be used according to the invention Polyisocyanates in the form of an aqueous dispersion with subsequent fixing phase. The aqueous padding liquors of the polyisocyanates to be used according to the invention contain, for example, 0.1-20% by weight of polyisocyanate, preferably 2- 20% by weight. The dyed textile is used for the block application Deflection rollers through a chassis with the polyisocyanate dispersion. By downstream squeeze rollers becomes a defined pick-up of the liquor ensured.

The aqueous polyisocyanate dispersions, which are used as padding liquor the, may contain other auxiliaries and additives such as. B. urea, Wetting agents, dispersants and thickeners in amounts of, for example 0.1 to 10% based on the padding liquor. The following are preferred examples Block fleet called:

The fleet intake is generally 50 to 120% of the weight of the goods Pad liquor temperature is preferably 20 to 30 ° C.

Possible fixation options are:

• a) Cold residence times at a temperature of 15 to 30 ° C for 12 to 24 Hours (semi-continuous mode of operation).
• b) treatment with saturated steam at 100 to 106 ° C, for a few minutes ten, preferably 1 to 3 minutes (continuous operation).
• c) dry heat fixation at 100 to 210 ° C within a few minutes, esp special 1 to 3 minutes (continuous operation).
• d) HT steam treatment at 150 to 200 ° C., preferably for 1 to 15, especially 2 to 8 minutes (continuous operation).

After fixing, significantly better fastness properties, in particular Fastness to washing, achieved than with normal direct dyeings.

If washing is still carried out at 90 to 95 ° C after the fixing phase, they are washed again improved wash fastness achieved so far only when using Reaktiv dyes could be achieved.

Example I a) Preparation of the polyisocyanate

1.0 val of an isocyanurate group-containing polyisocyanate based on 1.6- Diisocyanatohexane (HDI) with an NCO content of 21.5% and a viscosity of 3,000 mPas (23 ° C) were stirred at room temperature with 0.11 Val of a monofunctional polyethylene oxide polyether started on methanol an average molecular weight of 350 and then for 3 h Heated to 100 ° C. After cooling to room temperature there was a practically colorless one clear polyisocyanate mixture. The NCO content was 16.0% and the viscosity 3,050 mPas (23 ° C).

8 parts of the polyisocyanate thus obtained were mixed with 2 parts of propylene glycol diluted diacetate. An 80% solution with an NCO content of 12.8% and a viscosity of 510 mPa.s

b) application

20 g of a cotton nettle fabric were dyed with 0.3 g of the dye (II) in the exhaust process at 90 to 95 ° C. (30 g / l sodium sulfate, liquor ratio 1:20, 30 minutes). After rinsing and drying, the dyed fabric was padded out with a padding liquor
75 parts of a polyisocyanate, prepared according to a)
1 part of wetting agent (Erkantol AS)
10 parts of thickener (Levalin TM) and
914 parts of water treated.

The fleet intake was 85% of the weight of the goods. Then 15 h lingers at 30 ° C. It was then rinsed with hot water at 90 to 95 ° C. and dried. The deep black textile thus obtained had very good fastness properties.  

Example 2

Analogously to Example 1, 20 g of cotton fabric with 0.2 g of dye of the formula

colored. The dyed textile was rinsed and dried and then washed out with a padding liquor
75 parts of polyisocyanate according to Example 1 a),
100 parts of urea and
825 parts of water
treated on the foulard (fleet absorption 88%).

The textile thus obtained was dried at 120 ° C. for about 1 minute and then for 1 minute. fixed at 150 ° C. After rinsing, a brilliant, yellowish red color became received with good wash fastness.

Example 3

Analogously to Example 2, 20 g of cotton fabric with 0.2 g of the dye of formula

dyed and aftertreated with a padding liquor according to Example 2. This resulted in one clear blue color with good fastness properties.  

Example 4

Analogously to Example 2, 20 g of cotton fabric with 0.7 g of the dye (I) formula

dyed and aftertreated with a pad liquor Example 2. It became deep Preserved black coloring with a good level of authenticity.

Claims (9)

1. Process for dyeing fibers containing OH and / or NH groups with dyes that have at least one primary or secondary amino group have, in the presence of at least one water-dispersible Polyisocyanate. 2. The method according to claim 1, characterized in that the fibers during the dyeing process or afterwards with at least one water-dispersible polyisocyanate are treated. 3. Process according to claims 1 and 2, characterized in that as water-dispersible polyisocyanates

• (I) water-dispersible nonionic polyisocyanate mixtures of poly isocyanates and polyether-modified polyisocyanates with cycloaliphatic and / or araliphatic and / or aliphatic isocyanate groups, which may contain ester and / or amide groups in the main chain,
• (II) polyisocyanate mixtures of polyisocyanates and carboxylate group-modified polyisocyanates with cycloaliphatic and / or aliphatic bound isocyanate groups or
• (III) water-dispersible, nonionic polyisocyanates with aromatically bound isocyanate groups or mixtures of such polyiso cyanates

be used. 4. Process according to claims 1-3, characterized in that as water-dispersible polyisocyanates with polyisocyanate mixtures (I)

• a) an average NCO functionality of 1.8 to 4.2, preferably 2.1 to 4.2,
• b) a content of aliphatic and / or cycloaliphatic isocyanate groups (calculated as NCO, molecular weight = 42) of 3.0 to 21.5% by weight, based on the polyisocyanate mixture (I),
• c) a content of ethylene oxide units arranged within polyether chains (calculated as C₂H₄O, molecular weight = 44) of 2 to 20% by weight, based on the polyisocyanate mixture (I), the polyether chains having a statistical average of 5 to 70 ethylene oxide units, and
• d) a content of ester groups of 0 to 300 mol% and a content of amide groups of 0 to 300 mol%, based on the free NCO groups contained in the mixture

be used. 5. The method according to claims 1-4, characterized in that the water-dispersible polyisocyanates in amounts of 0.005 to 50% by weight based on the weight of the fibers to be dyed. 6. The method according to claims 1 to 5, characterized in that those of the formula as dyes wherein
FB for the rest of a dye chromophore,
Z₁ for a bridge member -CO-, -SO₂- or Z₂ for a pontic the bridge member Z₁ or Z₂ is bound to an N atom in FB,
Y represents Cl, OH, NH₂ or an aliphatic or aromatic amine radical, optionally also for X,
X for a basic group preferably -NR²-Q-NR³R⁴, or
a rest of the formula wherein the aromatic rings may have additional substituents such as SO₃H, CO₂H, CH₃, C₂H₅, Cl, Br, CH₃O, C₂H₅O,
Q for linear or branched C₂-C₆ alkylene,
R² is hydrogen or C₁-C₄-alkyl,
R³ and R⁴ independently of one another for hydrogen, unsubstituted C₁-C₆-alkyl, C₂-C₆-alkyl substituted by hydroxy or cyano, phenyl-C₁-C₃-alkyl, the phenyl radical of which by up to three substituents from the series chlorine, C₁-C₄- Alkyl and C₁-C₄-alkoxy may be substituted, Cub-C₆-cycloalkyl which is unsubstituted or substituted by up to three C₁-C₄-alkyl groups, or
R³ and R⁴ together with the N atom bonded to them form a 5- or 6-membered, optionally another heteroatom from the series O, N, S including a saturated ring,
m for an integer from 1 to 4,
n for 0 or an integer from 1 to 4 and
p represents 0 or an integer from 1 to 3,
the conditions n + 2p <m + 1 and n + p ≠ 0 apply to the number of basic groups X present,
which can be present as an inner salt. 7. The method according to claims l to 6, characterized in that it is the fibers to be dyed are those made of cellulose, wool or their Mixtures or any mixtures of the types of fibers mentioned Polyamide or polyester.