WO2008154671A1

WO2008154671A1 - Process for treating cellulosic fibres

Info

Publication number: WO2008154671A1
Application number: PCT/AT2008/000223
Authority: WO
Inventors: Andrew Hunter Morris Renfrew; James Martin Taylor; Heidrun Fuchs
Original assignee: Lenzing AG; Chemiefaser Lenzing AG
Current assignee: Lenzing AG
Priority date: 2007-06-21
Filing date: 2008-06-20
Publication date: 2008-12-24
Anticipated expiration: 2009-12-21
Also published as: AT505504A1; AT505504B1

Abstract

The present invention relates to a process for treating cellulosic fibres and for compounds that are suitable to be used in said process. According to the process of the invention, the cellulosic fibres are contacted with a textile auxiliary agent of the general formula (I) wherein: n = 0 or 1; X = halogen, especially Cl or Br, alkoxyl, hydroxyl, optionally substituted alkyl or arylamino; Z = a vinyl group, or a group -CH2CH2-U, where U is a group displaceable by alkali, e.g. Cl, OSO3H or SSO3H; A and B can be the same or different and may be H, methyl, methoxyl or a sulphonic acid group; D = an optionally substituted alkyl, aralkyl or aryl group; Y = a primary or secondary amino group; R and R1 independently are H, methyl or ethyl, or a salt thereof, respectively.

Description

Process for treating cellulosic fibres

The present invention relates to a process for treating cellulosic fibres and for compounds that are suitable to be used in said process. The process according to the invention renders cellulosic fibres suitable for dyeing with reactive dyes, under neutral or weakly acidic conditions. Moreover, if the treated cellulosic fibres are blended with non-cellulosic fibres such as polyester or wool, such blended materials are now suitable for a one-bath, one-step, dyeing procedure.

Background

Problems arise in colouring cellulosic fibres with reactive dyes. Fixation is normally carried out at pH 1 1-12, and hydrolysed reactive dye is always a significant by-product of fibre reaction. Accordingly, very large quantities of coloured effluent are generated worldwide, which potentially present an environmental hazard and which require expensive treatment before disposal. Moreover, reactive dyes for cellulosic fibres use large quantities of electrolyte which also presents problems of disposal.

The dyeing of blended fibres or fabrics, e.g. of blends of polyester and cellulosic fibres gives rise to an added difficulty. While dyes are known which allow a one-bath, one step dyeing, of blends of polyester and cellulosic fibres, they do not build-up and are suitable only for pale to medium shades. Generally, each fibre has to be dyed under a different set of conditions which is time consuming and costly.

It is an object of the present invention to provide a process for the treatment of cellulosic fibres whereby the treated fibres can be dyed easily with, e.g., a reactive dye without the above-mentioned drawbacks.

This object is solved by a process for treating cellulosic fibres, wherein the fibres are contacted with a textile auxiliary agent which is characterized in that a compound of the general formula (I)

wherein n = 0 or 1 ,

X = halogen, especially Cl or Br, alkoxyl, hydroxyl, optionally substituted alkyl or arylamino,

Z = a vinyl group, or a group -CH₂CH₂-U, where U is a group displaceable by alkali, e.g. Cl,

OSO₃H or SSO₃H,

A and B can be the same or different and may be H, methyl, methoxyl or a sulphonic acid group,

D = an optionally substituted alkyl, aralkyl or aryl group,

Y = a primary or secondary amino group,

R and Rj independently are H, methyl or ethyl,

or a salt thereof, respectively, is used as the textile auxiliary agent.

It has been found that the compounds of formula (I) address the above-mentioned problems. Fibres and textile assemblies that are pre-treated with the compounds according to the process of the present invention allow the fixation of cellulose reactive dyes under neutral or weakly acidic conditions, thereby preventing or greatly minimising hydrolysis of the dyes. Dyebaths, containing unused dye and electrolyte, can therefore be recycled, greatly reducing the volume of effluent for treatment.

So-called "cationized" cellulose fibres are known from the state of the art. The manufacture of cationized cellulosic fibres is described, for instance, in JP-A 61-258801, JP-A 52-26561 , JP-A 2-274738, EP-A O 683 251, EP-A O 690 166 or WO 96/26220. However, none of these processes and products has enjoyed even moderate success up to. now.

Preferred textile auxiliary agents to be used in the process according to the present inventions are those of formulae (II) to (X) below:

(VI)

The textile auxiliary agent may be used in the form of the sodium, lithium, potassium, calcium or magnesium salt.

According to a preferred embodiment of the present invention, the treatment is carried out in a neutral to alkaline environment.

Especially, the fibres may be contacted with an alkaline solution of the textile auxiliary agent.

The cellulosic fibres to be treated with the process according to the invention may be selected from the group consisting of cotton fibres, Viscose fibres, Modal fibres, Lyocell fibres and mixtures thereof. In a preferred embodiment, the cellulosic fibres are Lyocell fibres and are provided in the never-dried state. As "never-dried state", the skilled artisan understands the state of the freshly spun Lyocell fibre before it has been dried for the first time.

In the process according to the present invention, the cellulosic fibres may be provided as fibre assemblies or as a component of a fibre assembly, respectively. For example, the process according to the invention may be carried out on a web of freshly spun fibres, on a tow of endless filaments, on a nonwoven product containing cellulosic fibres, on a yarn, on a fabric, and so on.

The process according to the present invention may further comprise the step of dyeing the fibres with a dye selected from the group consisting of reactive dyes, acid dyes, vat dyes, direct dyes and disperse dyes. Dyeing with a reactive dye is preferred.

The dyeing step may be conducted with sets of parameters that are well known per se to the skilled artisan.

In the case of using a reactive dye, the dyeing step may be carried out at a pH value of from 4 to 12, preferably 5 to 9, most preferred 6 to 8. This means that the dyeing step can be conducted at neutral or only weakly acidic conditions.

The dyeing step may be carried out at room temperature (15-30⁰C) up to temperatures of 40- 95⁰C. Steaming at around 100⁰C and/or pad dry bake processes up to 200⁰C may also be employed.

The present invention also relates to a compound of the general formula (I)

wherein n = 0 or 1 , X = halogen, especially Cl or Br, alkoxyl, hydroxyl, optionally substituted alkyl or arylamino,

OSO₃H or SSO₃H,

D = an optionally substituted alkyl, aralkyl or aryl group,

Y = a primary or secondary amino group,

R and R| independently are H, methyl or ethyl,

or a salt thereof.

Compounds of formula (I) are novel.

As the skilled artisan will understand, compounds of formula (I) wherein X = hydroxyl are present in a tautological equilibrum between the two tautomeric forms

Preferred compounds are those of formulae (II) to (X) below:

(III)

(VIII)

The compounds of the present invention may be prepared in a manner known to the skilled artisan, for example by stepwise replacement of the chlorine atoms of cyanuric chloride, to introduce the new functional groups, or by transformation of a suitable dichlortriazine, firstly with a tertiary amine to make a triazinyl betaine followed substitution of the so-formed quaternary group with a suitable diamine.

Examples:

Example 1 :

(a) To p-aminophenyl-β-sulphatoethylsulphone (14.2 g; 0.05 m) in ice water (100 mis) was added 2 M sodium carbonate to give pH 4.5. The solution so formed was filtered through celite, cooled to OoC, and a solution of cyanuric chloride (9.7 g; 0.053 m) in acetone (100 mis), added dropwise, while maintaining a temperature of 0-2oC and pH 4 - 4.5. The reaction was continued for 2 hrs giving a white precipitate.

HPLC showed the reaction to be complete with the disappearance of the aromatic amine. The reaction mixture was allowed to warm to room temperature and left to stir for 2 hours at pH 4. The precipitate was isolated by filtration and the white solid so obtained, added portionwise to a solution of nicotinic acid (12.4 g; 0.1 m) in water (200 mis) at room temperature and pH 4.5. The pH was maintained at 4.5 with 2 M sodium carbonate solution. A pale yellow colour developed and the reaction continued for 24 hours. HPLC showed the reaction to be virtually complete. The yellow suspension was filtered, the solid washed, in turn with water ( 100 mis), and acetone (200 mis) and air-dried to give the product as a pale yellow solid (19g). The structure of the intermediate is shown below.

(b) The above pale yellow solid (18.7g), was added portionwise to a solution of p- phenylenediamine (4.1 g) in water (200 mis) at room temperature and pH 4.7-5. The pH was maintained at 4.7-5.0 with 2 M sodium carbonate solution and the reaction mixture was stirred for 24 hours, to give a pale purple coloured suspension. HPLC showed a new band and the reaction to be virtually complete. The suspension was filtered, the collected solid washed firstly with water (50 mis), then with acetone (200 mis) and dried in the air to give the product (12 g). HPLC showed a single peak and mass spectral analysis gave a molecular ion at m/z 481 (M-H)^" (100) and a sodium adduct at m/z 503 (M+Na-2H)^"(25). The structure of the pre-treatment agent is shown below.

1a

The above agent was applied to a fabric consisting of Lyocell fibre, at 2% omf, by a pad- steam application, in the presence of sodium carbonate, to give an off-white textile. A 2% dyeing, with Procion Red HE-3B, under neutral conditions, and at 100⁰C, furnished a fabric of equal colour value (K/S) and light fastness, to that of an untreated Lyocell fabric dyed with the same dye but under conventional alkali conditions.

Example 2

Cyanuric chloride (9.2 g; 98%; 0.05mol) was added to water (400 ml) containing mixed phosphate buffer ( I g) and Calsolene oil (5 drops). The suspension was stirred at 23°C, the pH maintained at 7-8 by the addition of sodium hydroxide solution (2M) and held at this pH for 2 hours, until everything was dissolved. 1,2-Diaminopropane (7.4 g; 99%; 0.10 mol) was added and the mixture stirred for approximately two hours. The pH was then adjusted from 10.7 to 5.9 with concentrated hydrochloric acid.

/?-Aminophenyl-β-sulphatoethylsulphone (13.6 g; 95.5%; 0.05 mol) was added, the pH adjusted to 4 and the reaction continued, with sodium carbonate solution (2M) used, to maintain a pH of 4-4.5. When the pH was steady, the reaction mixture was allowed to stir for an hour at a constant pH of 3.9, and the white solid which formed isolated by filtration, washed with water and dried in an electric oven at 40⁰C overnight.

The product (12.3g) showed a single band on HPLC at tR 0.66 and analysis by mass spectrometry gave ions at 449 (M+H)⁺ (35), 369 (M+H-SO₃)⁺(4) and 282 (100). The structure is shown below:

Application of this agent to cotton, by an exhaust dyeing method, gave a white fabric. Fixation of reactive dyes, under neutral dyeing conditions, at the boil, gave colour values comparable to those from conventional dyeing with alkali.

Example 3

To crushed ice / water (80OmL) was added cyanuric chloride (186.3g;1.0 mole) and Sera Wet C-NR wetting agent (5 drops). A solution of 3-aminobenzene-sulphonic acid was added drop-wise maintaining 0-5⁰C and pH 6.5 at all times. The addition was carried out over a period of 20 minutes then allowed to warm to 12⁰C to give the Dichlorotriazine (DCT). To a 1 litre beaker was added 1 ,4-phenylenediamine (1 1 1.4g; 1.02 mole) followed by water (40OmL). The contents of the beaker were then adjusted to pH 3.0 by the drop-wise addition of cone, hydrochloric acid. Total final volume of solution was 70OmL.

The solution containing the product of stage 1 (DCT) was adjusted to pH 3 by the drop-wise addition of concentrated hydrochloric acid. The 1 ,4-phenylenediamine solution was added drop-wise while maintaining pH 3.0 at all times, by the addition of IM Na₂CO₃ to give a suspension. The suspension was filtered, the filter cake slurried in acetone (IL), refiltered and dried at 4O⁰C to give the product, (424.2g; strength 87%;) as an off-white solid in 91% yield. The structure is as shown below:

Application to viscose by an exhaust dyeing method gave an off white fabric, to which reactive dyes could be fixed under neutral dyeing conditions.

The following agents were synthesised in a similar manner:

Example 4

Example 5

Example 6

Example 7

Claims

Claims:

1. A process for treating cellulosic fibres, wherein the fibres are contacted with a textile auxiliary agent, characterized in that a compound of the general formula (I)

wherein n = 0 or 1 ,

X = halogen, especially Cl or Br, alkoxyl, hydroxyl, optionally substituted alkyl or arylamino.

OSO₃H or SSO₃H.

D = an optionally substituted alkyl, aralkyl or aryl group,

Y = a primary or secondary amino group,

R and R| independently are H, methyl or ethyl,

or a salt thereof, respectively, is used as the textile auxiliary agent.

2. A process according to claim 1 , characterized in that the textile auxiliary agent is selected from the group of compounds having the following formulas (II) to (X)

(H)

(VII)

3. A process according to any one of the preceding claims, characterized in that the textile auxiliary agent is used in the form of the sodium, lithium, potassium, calcium or magnesium salt.

4. A process according to any one of the preceding claims, characterized in that the treatment is carried out in a neutral to alkaline environment.

5. A process according to claim 4, characterized in that the fibres are contacted with an alkaline solution of the textile auxiliary agent.

6. A process according to any one of the preceding claims, characterized in that the cellulosic fibres are selected from the group consisting of cotton fibres, Viscose fibres, Modal fibres, Lyocell fibres and mixtures thereof.

7. A process according to claim 6, characterized in that the fibres are Lyocell fibres and are provided in the never-dried state.

8. A process according to claim 6, characterized in that the fibres are provided as fibre assemblies or as a component of a fibre assembly, respectively.

9. A process according to any one of the preceding claims, further comprising the step of dyeing the fibres with a dye selected from the group consisting of reactive dyes, acid dyes, vat dyes, direct dyes and disperse dyes.

10. A process according to any one of the preceding claims, further comprising the step of treating the fibres with an agent selected from the group of fragrances, therapeutically active materials, flame retardant or flame resistant materials, odour absorbing materials and water proofing materials.

1 1. A compound of formula (I)

wherein n = 0 or 1 ,

OSO₃H or SSO₃H,

D = an optionally substituted alkyl, aralkyl or aryl group,

Y = a primary or secondary amino group,

R and R[ independently are H, methyl or ethyl,

or a salt thereof.

12. A compound according to claim 1 1, selected from the group of compounds having the following formulas (II) to (X)

(III)

(VI)