EP0013892B1 - Process for dyeing synthetic fibre materials by the extraction method - Google Patents

Abstract

1. Process for dyeing synthetic, hydrophobic fibre materials with organophilic dyestuffs, which are free from sulphonic acid groups, by the extraction method, in which the liquor, which circulates in a closed circuit, flows through a dyestuff depot from which the dyestuff is removed by a dissolution process and is then fed to the material to be dyed, characterized in that the depot is charged with non-finished, if necessary coarsely comminuted or spray-dried dyestuffs having a minimum solubility of 20 mg/l in water at 130 degrees C and an aqueous, emulsifier-free dyeing liquor is allowed to flow through the depot at the dyeing temperature.

Description

The invention relates to a process for dyeing synthetic, hydrophobic fiber materials with organophilic dyes free of sulfonic acid groups by the extraction method.

This special variant of an exhaust process, in which the liquor, which is expediently circulating in a circuit, flows through a dye depot, from which the dye is removed by a dissolving process and then fed to the material to be colored, is known (cf. DE-A-1 918 309, 1,938,792 and 2,215,336).

The known processes are almost exclusively aimed at the use of organic solvents as the liquor medium, but they have the disadvantage that the dyes introduced therein have a distribution coefficient which is substantially lower than that of water as the coloring medium. This fact in turn means that when using organic solvents, complete bath exhaustion is never achieved, which necessitates complex cleaning operations on the dyeing machines.

The colorings often leave something to be desired in terms of rub fastness and levelness.

There has been no lack of attempts to overcome these disadvantages, for example by switching on special filters (cf. DE-A-2 047192).

However, these methods have so far not been successful in practice.

In the patent literature cited above, the use of water as a coloring medium is sometimes also suggested, but without giving detailed information on the technical implementation of this idea.

In Example 18b of DE-A-2 247 568 alone, a Soxhlet apparatus is described in which the colorant is deposited in a glass fiber sleeve which is de facto flowed through by the cold water condensed on the reflux condenser of the apparatus.

This variant of the method has also so far not been used in practice, since the extraction process is too slow.

It has now been found that, while overcoming the disadvantages dealt with above, the extraction process known per se can be carried out in a simple manner, i.e. can be used for dyeing hydrophobic fibers without using special preparations and while observing economically interesting dyeing times, if the depot is loaded with a dye with a minimum solubility in water of 20 mg / l at 1'30 ° C and flowed through by an aqueous dye liquor at dyeing temperature leaves that is free of emulsifiers and dispersants.

The flow through the fleet can take place directly or indirectly in a so-called by-pass.

The execution of this dyeing process or the dye depots is not tied to certain equipment requirements. The use of precoat filters, as recommended in DE-A-1 918 309 for dyeing from organic solvents, is also possible, such as, for example, fine-meshed filter baskets or systems which enable liquid / liquid extraction with relatively low-melting dyes. Systems of this type are already recommended for the use of dye solutions in water-immiscible solvents (DE-A-2 239563).

Suitable dyes for carrying out the process are described in detail and comprehensively in the patent literature or - in the case of commercial products - are listed in the Color Index. They can belong to a wide variety of chromophoric systems. Examples include dyes from the azo, anthraquinone, quinophthalone, perinone and methine series, and organophilic optical brighteners.

Suitable dyes are, in particular, those which are more than 50 mg / l, in particular 100 mg / l, soluble in the aqueous liquor at 130 ° C.

The solubility in water is determined by methods known per se, for example by taking a measured amount of dye solution at 130 ° C. from a suitable apparatus, as described, for example, in Melliand Textile Reports 11, (1969), page 1342, using a sample with Water-miscible polar, organic solvents (eg dimethylformamide) are diluted and the dye content therein is determined photometrically.

-SO₂-V, -SO₂-OV, -NH-SO2-V,

-(Alkylen-O-)_nV', -CH₂-CH₂-CN,

wobei V für gegebenenfalls substituiertes Alkyl, Aralkyl oder Aryl, V, und V2 für Wasserstoff oder gegebenenfalls substituiertes Alkyl, Aralkyl oder Aryl, V' für V, oder Acyl und n für Zahlen von 1 - 8 stehen.Particularly suitable are dyes which carry a hydrophilizing substituent group R, such as -COOH, -COOV, -O-COOV, -O-CONHV,

-SO ₂ -V, -SO ₂ -OV, -NH-SO2-V,

- (alkylene-O-) _n V ', -CH ₂ -CH ₂ -CN,

where V is optionally substituted alkyl, aralkyl or aryl, V, and V2 is hydrogen or optionally substituted alkyl, aralkyl or aryl, V 'is V, or acyl and n are numbers from 1-8.

oder C₂H₄ON, wobei V und n die oben angegebene Bedeutung haben.Of particular importance from this group are those dyes which carry the following substituents: -COOH, -COOV, -O-COOV, -O-CO-NH-V, - (CH ₂ -CH ₂ -O-) _n V

or C ₂ H ₄ ON, where V and n have the meaning given above.

• • a) Monoazofarbstoffe der Formel
    
    in der
    • D für den Rest einer aromatischen carbocyclischen oder heterocyclischen Diazokomponente steht,
    • Ar für den Rest einer aromatischen carbocyclischen oder heterocyclischen Kupplungskomponente und
    • K, und K2 H, Alkyl, Aralkyl, Aryl- oder Oxalkylgruppen bedeuten,
    • wobei K₁, K₂ oder Ar gegebenenfalls über ein Brückenglied mindestens einmal den Substituenten R tragen.
  • b) Monoazofarbstoffe der Formel
    
    in der
    • D, für den Rest einer carbocyclischen oder heterocyclischen Diazokomponente steht, die mindestens einmal den Substituenten R gegebenenfalls über ein Brückenglied gebunden trägt, Ar die in a) angegebene Bedeutung hat und
    • K₃ und K₄ H oder gegebenenfalls substituierte Alkyl-, Aryl-, Aralkyl- bzw. Oxalkylgruppen bedeuten.
  • c) Monoazofarbstoffe der Formel
    
    in der
    • D2 für den Rest einer carbocyclischen oder heterocyclischen Diazokomponente steht und
    • K für den Rest einer Kupplungskomponente der Phenol-, Naphthol-, Acylessigsäureamid-, Pyrazol-, Pyridin- oder Chinolin-Reihe, wobei mindestens einer der Reste D2 oder K mindestens einmal den Substituenten R trägt, der gegebenenfalls über das phenolische bzw. enolische Sauerstoffatom gebunden ist.
  • d) Disazofarbstoffe der Formel
    
    in der
    • Ar₂ einen Arylenrest bedeutet.
    • Ar, und Ar3 stehen für Aryl- oder Hetarylreste, wobei in Ar₁, Ar₂ oder Ar₃ mindestens einmal ein Substituent R vorhanden sein muss.
  • e) Anthrachinonfarbstoffe der allgemeinen Formel
    
    worin
    • E für Halogen, bevorzugt Brom oder Chlor steht, für Alkoxy- oder Aryloxy, für die Carboxylgruppe bzw. deren funktionelle Derivate oder gegebenenfalls subst. Alkyl- und Arylreste,
    • n 0, 1 oder 2 bedeutet,
    • A₁, A₂, A3 oder A4 jeweils Wasserstoff, eine gegebenenfalls durch Alkyl-, Aralkyl-, Cycloalkyl-, Aryl- oder Hetaryl-Reste substituierte Aminogruppe der Hydroxy- oder Nitrogruppe bedeuten, wobei mindestens einer der Reste A,, A2, A₃, A4 eine gegebenenfalls subst. Aminogruppe oder Hydroxy darstellt und die Substituenten A,-A4 E oder der Anthrachinonkern sebst mindestens einmal den Substituenten R gegebenenfalls über ein Brückenglied gebunden trägt.
  • f) Chinophthalonfarbstoffe der Formel
    
    in der
    • E, und E2 Wasserstoff, Halogen, Alkoxy, Acyloxy, Acylamino oder die Carboxylgruppe bzw. deren funktionelle Derivate bedeuten,
    • m 0, 1 oder 2 bedeutet und der Chinolin oder der Phthaloylrest mindestens einmal den Substituenten -G-R trägt.
  • g) Nitro-Diarylaminofarbstoffe der Formel
    
    in der
    • E3 Wasserstoff, Alkoxy oder Aryloxy, substituierte Amino, Halogen, Arylazo, Carboxyl oder funktionelle Derivate eines Sulfonsäure oder Carboxyl-Restes bedeuten und mindestens einer der aromatischen 'Ringe oder E3 mindestens einmal den Substituenten -R trägt.
  • h) Methinfarbstoffe der Formel
    
    in der
    • K, und K2 H oder gegebenenfalls substituierte Alkyl, Aralkyl bzw. Oxalkylgruppen bedeuten.
    • E4 steht für Wasserstoff, Alkyl oder Alkoxy
    • V, und V2 stehen für Nitril, Alkoxycarbonyl, Alkylcarbonyl oder Alkylsulfongruppen, wobei entweder V₁, V₂, K,, K₂, E₄ oder der aromatische Ring mindestens einmal den Substituenten R tragen.

Particularly preferred dyes are derived, for example, from the following classes of compounds:

• • a) Monoazo dyes of the formula
    
    in the
    • D represents the remainder of an aromatic carbocyclic or heterocyclic diazo component,
    • Ar for the rest of an aromatic carbocyclic or heterocyclic coupling component and
    • K and K2 are H, alkyl, aralkyl, aryl or oxalkyl groups,
    • where K ₁ , K ₂ or Ar optionally carry the substituent R at least once via a bridge member.
  • b) monoazo dyes of the formula
    
    in the
    • D stands for the remainder of a carbocyclic or heterocyclic diazo component which at least once carries the substituent R optionally bound via a bridge member, Ar has the meaning given in a) and
    • K ₃ and K _{4 are} H or optionally substituted alkyl, aryl, aralkyl or oxalkyl groups.
  • c) monoazo dyes of the formula
    
    in the
    • D2 represents the remainder of a carbocyclic or heterocyclic diazo component and
    • K for the rest of a coupling component of the phenol, naphthol, acylacetic acid amide, pyrazole, pyridine or quinoline series, at least one of the radicals D2 or K bearing at least once the substituent R, which may be via the phenolic or enolic oxygen atom is bound.
  • d) disazo dyes of the formula
    
    in the
    • Ar _{2 represents} an arylene radical.
    • Ar and Ar3 stand for aryl or hetaryl radicals, whereby a substituent R must be present in Ar ₁ , Ar ₂ or Ar ₃ at least once.
  • e) Anthraquinone dyes of the general formula
    
    wherein
    • E stands for halogen, preferably bromine or chlorine, for alkoxy- or aryloxy, for the carboxyl group or its functional derivatives or optionally subst. Alkyl and aryl radicals,
    • n means 0, 1 or 2,
    • A ₁ , A ₂ , A3 or A4 each represent hydrogen, an amino group of the hydroxyl or nitro group optionally substituted by alkyl, aralkyl, cycloalkyl, aryl or hetaryl radicals, at least one of the radicals A ,, A2, A ₃ , A4 a possibly subst. Represents amino group or hydroxy and the substituents A, -A4 E or the anthraquinone nucleus itself at least once carries the substituent R optionally bound via a bridge member.
  • f) quinophthalone dyes of the formula
    
    in the
    • E and E2 are hydrogen, halogen, alkoxy, acyloxy, acylamino or the carboxyl group or their functional derivatives,
    • m denotes 0, 1 or 2 and the quinoline or the phthaloyl radical bears the substituent -GR at least once.
  • g) nitro-diarylamino dyes of the formula
    
    in the
    • E3 is hydrogen, alkoxy or aryloxy, substituted amino, halogen, arylazo, carboxyl or functional derivatives of a sulfonic acid or carboxyl radical and at least one of the aromatic rings or E3 bears the substituent -R at least once.
  • h) methine dyes of the formula
    
    in the
    • K, and K2 are H or optionally substituted alkyl, aralkyl or oxalkyl groups.
    • E4 stands for hydrogen, alkyl or alkoxy
    • V and V2 stand for nitrile, alkoxycarbonyl, alkylcarbonyl or alkylsulfone groups, with either V ₁ , V ₂ , K ,, K ₂ , E ₄ or the aromatic ring bearing the substituent R at least once.

Unless otherwise defined, the alkyl and alkoxy radicals mentioned above in any context preferably have 1-4 C atoms and can be or auxiliary chemistry usual substituents (eg OH, CN, Cl, NO ₂ , F, Br, alkoxycarbonyl or alkoxy), with the exception of ionic radicals (except COOH) in the dye radicals. Suitable aryl or aryloxy radicals are naphthalene and especially benzene radicals, which may be substituted by alkyl, alkoxy, CI, F, Br, NO ₂ , alkoxycarbonyl, CF ₃ , CN or COOH subst. are. Suitable hetaryl radicals are pyridyl, thienyl, furyl, quinolinyl, thiazolyl, thiadiazolyl and pyrazolyl.

Suitable alkylene radicals preferably have 2-10 C atoms in the chain, which can optionally be substituted by alkyl, aryl, aralkyl or COOH. -C2H4- is preferred.

Suitable arylene residues are naphthylene and especially phenyl residues, e.g. by alkyl or aryl subst. could be.

Suitable bridge members are O, S, CO, alkylene, phenylene and others.

Suitable derivatives of the carboxyl group are nitriles, carboxamides, alkyl esters, acid anhydrides and imides.

On the one hand, very particular preference is given to those dyes of the formulas given above which have at least one radical R = - (CH ₂ CH ₂ -O) _n -V and where n = 2-5, preferably = 3-4, and on the other hand those of these formulas which have at least one radical R = COOV, OCOOV, OCONHV, C ₂ H ₄ OH or C2H4CN.

• Farbstoffe der Azobenzolreihe,
• die in der Kupplungskomponente die vorstehend genannten Reste und in der Diazokomponente in ortho- und/oder para-Stellung zur Azolreihe stark elektronenziehende Substituenten, wie CN, NO2, S02-Alkyl, aufweisen, sowie der Hetarylazobenzolreihe.

Within the latter type are preferred:

• Azobenzene series dyes,
• which in the coupling component have the abovementioned radicals and in the diazo component in the ortho and / or para position to the azole series strongly electron-withdrawing substituents, such as CN, NO2, SO2-alkyl, and the hetarylazobenzene series.

worin

• R, für C₂H₄OH, C₂H₄OCOCH₃, C₂H₄0COOCH₃, C₂H₄OCOOC₂H₅, C₂H₄COOCH₃, C₂H₄COOC₂Hs, C₂H₄OC₂H₄OCH₃, C₂H₄0CONHX,
• R₂ für R, oder H, C₂H₅, C₂H₄CN, C₂H₄OCH₃,
• R3 für H, CH, oder NHCOCH₃,
• R4 für H, CI oder OCH₃,
• Rs für CI, Br, CN, NO₂,
• R₆ für NO2, CN,
• R₇ für H, CI, Br oder CN und
• X für C₁-C₄-Alkyl oder Phenyl stehen.

Particularly preferred dyes correspond to the formula

wherein

• R, for C ₂ H ₄ OH, C ₂ H ₄ OCOCH ₃ , C ₂ H ₄ 0COOCH ₃ , C ₂ H ₄ OCOOC ₂ H ₅ , C ₂ H ₄ COOCH ₃ , C ₂ H ₄ COOC ₂ Hs, C ₂ H ₄ OC ₂ H ₄ OCH ₃ , C ₂ H ₄ 0CONHX,
• R ₂ for R, or H, C ₂ H ₅ , C ₂ H ₄ CN, C ₂ H ₄ OCH ₃ ,
• R3 for H, CH, or NHCOCH ₃ ,
• R4 for H, CI or OCH ₃ ,
• Rs for CI, Br, CN, NO ₂ ,
• R ₆ for NO2, CN,
• R ₇ for H, CI, Br or CN and
• X represents C ₁ -C ₄ alkyl or phenyl.

Suitable diazo components of these particularly preferred types are also

Very particularly preferred polyether dyes are those of the formula IX in which at least one of the radicals R ₁ -R _{7 represents} the radical - (C ₂ H ₄ O) _m X, which is attached to the azobenzene molecule directly or via a bridge, for example O or CO is bound and m is 2-5.

The dyes are used in the form of powder or granules or - according to a preferred process variant - as tablets. If appropriate, these molds can contain customary auxiliaries such as dispersants, mold release agents, blending agents, etc. An intensive grinding process, however, is not necessary when manufacturing these preparations.

The dyeings can be carried out at the boiling point of the aqueous dye liquor or - preferably - in closed dyeing systems at temperatures of approx. 130 ° C.

The fiber material is dyed in a weakly acidic to weakly alkaline bath, advantageously at a pH of 3.5-6; the liquor ratio can vary between 1: 3 to 1:40, preferably in the range 1: 8 to 1:20.

Auxiliaries with a known effect can be added to the dye liquor - for example phenol derivatives such as o-phenylphenol, methyl salicylic acid, chlorinated aromatic hydrocarbons such as o-dichlorobenzene or methylnaphthalenes or 2,2'-dinaphthylsulfonic acid sodium. Depending on the color depth and liquor ratio, the amounts of auxiliary agents which are added vary between 0.1 g / l and 4 g / l.

The aqueous moths, which apart from the specified auxiliaries can only contain the substances necessary for pH regulation, are generally free of organic solvents.

For dyeing by the process according to the invention, structures made of polyesters, cellulose acetates or polyamides are suitable as textile materials, these fibers being able to be used in a mixture with one another or together with natural fibers such as wool or cotton.

In the case of fiber mixtures, the present process for dyeing the synthetic fibers can be combined with dyeing operations for dyeing the native fiber components. Of course, dye mixtures are also used to dye a type of fiber using the dyeing process according to the invention.

The following examples illustrate the invention without being limited thereto. The percentages given are weight percent percent based on the material to be dyed; the temperatures are given in degrees Celsius.

example 1

C.I. Disp. Yellow 42 beschickt, die Anlage mit Wasser ohne jeden weiteren Zusatz gefüllt und die wässrige Flotte rasch auf 130°C aufgeheizt. Die Zirkulation durch den Wickelkörper erfolgt im Wechsel von 3 Min. bzw. 5 Min. von innen nach aussen und umgekehrt. Der Wasserstrom kann dabei sofort, d.h. mit Beginn der Aufheizphase oder auch erst nach Erreichen von 100 bzw. 130°C durch das Depot geleitet werden. Nach einer Färbezeit von 45 Min. bei 130°C ist der Farbstoff vollständig aus dem Depot gelöst und auf die Polyester-Kreuzspule aufgezogen. Das Färbebad wird nach Abkühlen auf ca. 80°C abgelassen. Nach einer kurzen Spülpassage erhält man eine Gelbfärbung in 1/1 Richttyptiefe von ausgezeichneter Egalität, die sich in keiner Weise in Farbtiefe und Farbton von einer wie üblich reduktive nachbehandelten 6%igen Färbung unterscheidet, die mit formiertem Handelsfarbstoff hergestellt wurde.500 parts of polyester yarn are dyed in the form of a bobbin in a bobbin dyeing machine with a dye depot; for this purpose, the depot with 9 parts of a coarsely comminuted, unformed dye of the formula

CI Disp. Yellow 42 is charged, the system is filled with water without any further additives and the aqueous liquor is quickly heated to 130 ° C. The circulation through the winding body takes place alternately from 3 minutes or 5 minutes from the inside to the outside and vice versa. The water flow can be directed through the depot immediately, ie at the beginning of the heating phase or only after reaching 100 or 130 ° C. After a dyeing time of 45 minutes at 130 ° C, the dye is completely detached from the depot and applied to the polyester cheese. The dyebath is drained after cooling to approx. 80 ° C. After a short rinsing passage, a yellow color in 1/1 standard depth of excellent levelness is obtained, which in no way differs in color depth and hue from a reductive aftertreated 6% coloration, which was produced with formed commercial dye.

(* L _{130 ° c} = solubility in water at 130 ° C)

Is the aqueous liquor used for pH regulation e.g. 1 g / l sodium acetate and 1 ml / l acetic acid 30 ° / oig added, so 'colorations are achieved with the same depth, brilliance and fastness.

Example 2

(C.I. Disp.-Violet 50) und 5% Binde- bzw. Trennmittel (hergestellt auf einem Rundlauf oder Exzenter-Tabletten-Presse mit Druck von 900 -1000 Atmosphären) beschickt und die Anlage mit Wasser gefüllt. Die Flotte wird so schnell wie möglich auf 130°C gebracht und 50 Minuten bei dieser Temperatur gefärbt. Nach dem Abkühlen und Ablassen der Flotte und Spülen erhält man eine rotviolette Färbung in 1/1 RTT, die sich nicht von einer red. nachbehandelten Färbung unterscheidet, die mit gefinishtem Farbstoff erhalten wird, wenn die eingesetzten Reinfarbstoffmengen beider Färbungen gleich sind.200 parts of polyester piece goods are wound onto a material carrier and used in the cross-winder dyeing unit described above. The 'depot is made with 1.1 parts of a tabletted dye consisting of 95% of the dye of the formula

(CI Disp.-Violet 50) and 5% binding or separating agent (produced on a rotary machine or eccentric tablet press with a pressure of 900-1000 atmospheres) and the system is filled with water. The liquor is brought to 130 ° C. as quickly as possible and dyed at this temperature for 50 minutes. After cooling and draining the liquor and rinsing, a red-violet color in 1/1 RTT is obtained, which does not differ from a red. post-treated coloring, which is obtained with finished dye if the amounts of pure dye used are the same for both dyeings.

Example 3

L_130° = 55 mg/I in Form eines Sprühgranulates und verfährt im übrigen wie in den Beispielen 1-2 angegeben, so erhält man eine brillante Rotfärbung, die in Farbtiefe, Farbton und Echtheiten einer Färbung nach konventioneller Färbemethode entspricht.Instead of the dye mentioned in Example 1, 0.22 ° / o of the dye of the formula is used

L _{130 °} = 55 mg / l in the form of a spray granulate and otherwise operates as indicated in Examples 1-2, a brilliant red color is obtained which corresponds in color depth, hue and fastness to a dyeing according to the conventional dyeing method.

If, instead of the dyes used in Examples 1-3, the ones listed in the following table are used, level dyeings with the same or even slightly higher color depths, as are obtained with conventionally finished disperse dyes according to the usual dyeing method, are obtained with the same procedure.

Claims (1)

1. Process for dyeing synthetic, hydrophobic fibre materials with organophilic dyestuffs, which are free from sulphonic acid groups, by the extraction method, in which the liquor, which circulates in a closed circuit, flows through a dyestuff depot from which the dyestuff is removed by a dissolution process and is then fed to the material to be dyed, characterised in that the depot is charged with non-finished, if necessary coarsely comminuted or spray-dried dyestuffs having a minimum solubility of 20 mg/l in water at 130°C and an aqueous, emulsifier-free dyeing liquor is allowed to flow through the depot at the dyeing temperature.