WO1999011747A1

WO1999011747A1 - Wash process for textiles

Info

Publication number: WO1999011747A1
Application number: PCT/EP1998/005401
Authority: WO
Inventors: Andreu Colomera; Teresa Copete Vidal
Original assignee: Cognis Deutschland Gmbh
Priority date: 1997-09-04
Filing date: 1998-08-26
Publication date: 1999-03-11
Also published as: DE19738625C1; EP1009798A1

Abstract

The invention relates to a wash process for textiles in which an aqueous bath containing only or mainly knitwear is treated with (a) 1 to 50 g/l powdered silicon compounds and (b) 0.5 to 4 g/l cellulases. In this way, besides the 'used look' imparted to the knitwear, slight wear of the fibres results simultaneously in a particularly pleasant soft feel of the knitwear.

Description

Washing process for textiles

Field of the Invention

The invention relates to a washing method for knitwear using defined amounts of ground silicon compounds and cellulases.

State of the art

In particular, very young consumers often want textiles that already give a worn impression ("used look") and at the same time have a pleasant soft feel, ie increased wearing comfort. In jeans, for example, this is referred to as a stonewash effect, the texture of which is combined chemical and mechanical treatment of the denim fabric with cellulases and pumice stone is achieved.

It was already known from the prior art that cellulases have the property of detaching blue indigo dye from denim fibers. An overview is given by N. Klange in C.R. 2nd TRICEL Symposium, Espoo, Finland, 1993, p. 263 published. In the further development of this knowledge, the European patent EP-B1 0452393 (Cayla) proposes a process for the heterogeneous prewashing of cotton textiles, which is carried out using certain cellulases at pH values below pH = 6. From European patent application EP-A2 0307564 (Ecolab) a method for creating differently colored areas of textiles made of cellulose by treatment with an aqueous liquor is known which, in addition to cellulases, can contain nonionic surfactants of the fatty alcohol ethoxylate type with up to 20 ethylene oxide units per mole of fatty alcohol .

In addition to the fact that pumice stone is a natural and expensive source of raw materials, the stones are ground so strongly after only one use that reuse is no longer an option. In the case of blue jeans, part of the pumice stones can also be found in the pockets and must be laboriously removed by hand. Another problem is that only a limited number of textiles can be treated in this way and a not inconsiderable part is so badly damaged by them in this procedure that it is no longer eligible for sale.

In this context, reference should be made to the relevant prior art for the exchange of pumice stone in textile washing processes. For example, in Chem. Abstr. 121, 282.299 proposed to replace pumice stones with ceramic or hard rubber balls. From US 5,213,581 a method for producing stonewashed jeans is known, in which cellulases are used together with inorganic salts, for example silicates. A similar process is proposed in WO 95/09225 (Ivax), wherein the stonewash effect is achieved with the aid of cellulases and unground silicates of the bentonite type are added to the liquor in order to prevent redeposition of the dye. However, the bentonites are not used to treat the fibers, i.e. have no abrasive properties. Finally, in WO 95/35363 (Novo) it is recommended to replace pumice stone with expanded perlite. Perlite is a volcanic lava rock that loses water at 1200 ° C and results in a lightweight rock foam when expanded. The foam breaks easily into small chunks, which can then be used like pumice stone without further crushing. However, the high resemblance to pumice stone means that the same problems are associated with the use of this material, in particular with regard to reusability and dust formation.

Less known than the use of cellulases and pumice stones for the surface treatment of denim fabrics is their use for producing a "used look" on knitwear, such as pullovers. At the present time, the method of choice is to pretreat the fabrics with pumice stones first and the liquor then add cellulases, but as described above, the use of pumice stone is associated with many problems and is therefore increasingly undesirable.

The object of the invention was therefore to provide a method for treating knitwear which at the same time produces a structural effect and improves the soft feel.

Description of the invention

The invention relates to a washing process for textiles, in which an aqueous liquor containing wholly or predominantly knitwear with

(a) 1 to 50 g / l ground silicon compounds and

(b) 0.5 to 4 g / l cellulases - based on the volume of the wash liquor - treated.

Surprisingly, it was found that ground silicon compounds, preferably ground silicates or ground glass, in combination with cellulases are not only ideally suited to producing a structural effect on knitwear and thus giving them a "used look", but also due to slight fiber abrasion on the Surface also improve the soft feel and thus the wearing properties noticeably.

Knitwear

Knitwear, which is also often referred to as knitted fabric, is to be understood as stretchable, textile fabrics which consist of mesh-like loops of thread. They therefore represent a differentiation from the so-called fabrics, which contain threads crossed at right angles. Typical examples of knitwear, on the treatment of which the method according to the invention is directed, are ware goods, such as, for example, stockings, gloves, pullovers and chain goods, such as, for example, jersey and underwear. The knitwear can consist of both vegetable and synthetic fibers. Although cotton fabrics are preferred, lyocell or cellulose fibers, for example, and fiber blends, for example with polyester or polyamide fibers, are also suitable.

Silicon compounds

Silicon dioxide is preferably used as the ground silicon compound, in the simplest case it is sand. However, preference is given to using ground silicates or ground glass, the origin of which is not critical. Accordingly, conventional recycling glass is basically just as suitable for the production of the regrind as, for example, expensive glass foam. For example, diatomaceous earth can be considered as a natural source. The silicate starting materials preferably contain no water of crystallization, so that they do not expand at higher temperatures; Perlite, which changes to a pumice stone-like mass at 1200 ° C, is therefore not an option as a starting material, because the same problems associated with pumice stone itself are associated with its use. Particularly good application results are obtained with ground silicates or ground glass, which have a grain size in the range from 0.01 to 200 μm and specifically have a composition in which 40 to 70% by weight of all particles have an average diameter of less than 50 μm, 40 to 70 wt .-% of 50 to 100 μm and 20 to 40 wt .-% of greater than 100 μm - with the proviso that the information is complementary to 100 wt .-%. Usually, the millbase is used in amounts of 0.5 to 2.5 and preferably 1.0 to 2.0 kg / kg of the textile fabric used. The production of the ground silicon compounds can be carried out according to the methods of the prior art in comminution machines suitable for this purpose, for example crushers, roller mills, grinding media mills or impact mills, as described, for example, in Winnacker-Küchler, Chemische Technologie, Vol. 1, 4th ed. P. 87-93 (1984).

Cellulases

Cellulases (1, 4-ß-D-glucan-4-glucanohydrolases; EC 3.2.1.4.) Are enzyme complexes that are involved in the breakdown of native cellulose. The acidic cellulases which are preferably to be used as optional component (b) in the sense of the invention are enzymes which are preferably prepared from cultures of Aspergillus or Trichoderma species and have an optimum activity at acidic pH values in the range from 4 to 6 . Acid cellulases, which are sold by Novo Nordisk under the Celluzyme® brand and are produced by submerged fermentation of the fungus Humicola insolens, are particularly preferred. Overviews of the interaction of cellulases with cellulose are, for example, from E.Hoshino in J. Biochem. 114, 230; 236 (1994), ibid. 115, 837 (1994) and J. Ferment. Bioeng. 77, 496 (1994). The cellulases are usually used in amounts of 0.1 to 15% by weight, based on the textile fabrics.

Zeolites

In a preferred embodiment of the process according to the invention, zeolites can be used as further additives. Zeolites are to be understood as meaning optionally water-containing alkali metal or alkaline earth metal aluminosilicates of the general formula (I)

M2zO * AI ₂ θ3 * x Siθ2 * y H ₂ 0 (I)

where M stands for an alkali or alkaline earth metal of valence z, x for numbers from 1, 8 to 12 and y for numbers from 0 to 8 [Chem.i.u.Zt., 20, 117 (1986)]. Typical examples of zeolites are the naturally occurring minerals clinoptilolite, erionite or chabasite. However, synthetic zeolites are preferred, for example

Zeolite NaA Naι [(AI0 ₂ ) i2 (SiO ₂ ) i2] * 27 H 0.

Zeolite NaX Na ₈ 6 [(AI0 ₂ ) 86 (Si0 ₂ ) ιo6] * 264 H ₂ 0

Zeolite Y Na ₅ 6 [(AlO ₂ ) 56 (SiO 2) i36] * 325 H ₂ 0

Zeolite LK ₉ [(AI0 ₂ ) 9 (Si0 ₂ ) 27] * 22 H ₂ 0 Mordenite Na ₈ , 7 [(Al0 ₂ ) ₈ , 7 (Si0 ₂ ) 39.3] * 24 H ₂ 0

For the purposes of the process according to the invention, zeolite NaA and mixtures of zeolite NaA and NaX are preferably used, the proportion of zeolite NaX in such mixtures advantageously being below 30%, in particular below 20%. Suitable zeolites have no particles larger than 30 mm and consist of at least 80% particles smaller than 10 mm. Their average particle size (volume distribution, measurement method: Coulter Counter) is in the range from 1 to 10 mm. Preferred zeolites have an average particle size of 2 to 4 mm. Their calcium binding capacity, which is determined according to the information in German patent application DE-AS 24 12 837, is in the range from 100 to 200 mg CaO / g. The zeolites, which are usually used in amounts of 1 to 15, preferably 1 to 10,% by weight, based on the textile fabrics, can also contain excess alkali from their production.

Nonionic surfactants

For the purposes of the process according to the invention, it has proven advantageous for enzyme stabilization and dust binding to use the cellulases together with suitable, preferably anhydrous, nonionic surfactants, such as, for example, fatty alcohol polyglycol ether of the formula (II),

in which R ^{1 is} a linear or branched alkyl radical having 12 to 22 carbon atoms and n is a number from 2 to 50 and preferably 5 to 30. Typical examples are addition products of an average of 2 to 50 and in particular 5 to 10 moles of ethylene oxide onto technical fatty alcohols with 12 to 18 carbon atoms such as, for example, dodecanol, isododecanol, coconut oil alcohol, isostearyl alcohol, cetearyl alcohol and / or tallow fatty alcohol. The nonionic surfactants are usually used in amounts of 1 to 15% by weight, preferably 1 to 10% by weight, based on the textile fabrics.

Buffer salts

Together with the surfactants, it is advisable to use buffer salts, which can be, for example, alkali and / or alkaline earth metal sulfates, carbonates, phosphates and citrates. Typical examples are sodium sulfate, potassium sulfate, calcium carbonate, sodium phosphate and sodium citrate. Although it is of course not a salt, citric acid can also be used. Polyethylene or polypropylene glycol ethers can also be used as dust binders an average molecular weight in the range of 500 to 5,000. The buffer salts are usually used in amounts of 1 to 10, preferably 1 to 3,% by weight, based on the textile fabrics.

Compounds

In a particular embodiment of the invention, the process can also be carried out using compounds of the following composition,

(a) 95 to 99, preferably 75 to 95% by weight of ground silicon compounds,

(b) 0.1 to 4, preferably 1 to 2% by weight of cellulase,

(c) 0.1 to 10, preferably I to 5% by weight of zeolites,

(d) 0.1 to 10, preferably 1 to 5% by weight of nonionic surfactants and

(e) 0.5 to 3, preferably 1.5 to 1.5% by weight of buffer salts,

with the proviso that the amounts add up to 100% by weight. The compounds can also be formulated as aqueous gel-like preparations, optionally with the use of polymers, which facilitates their use.

Execution of the procedure

The liquor weight ratio of the knitwear to water is preferably in the range from 1:10 to 1:30. Usually a liquor consisting of about 3 to 5 kg of knitwear and 30 to 50 kg of water is prepared, which is firstly treated with 3 to 5 kg of ground silicon compounds, preferably ground glass, and 50 to 100 and preferably 5 to 10 g of cellulase and optionally zeolites, anhydrous nonionic surfactants and / or buffer salts. It is advisable to carry out the process at a pH in the range from 5.0 to 5.5 and at a temperature in the range from 50 to 55 ° C. If desired, conventional laundry softeners, for example of the esterquat type, can be used together with the preparations. As described above, the process according to the invention can also be carried out using the appropriate compounds. Examples

Example 1. 2.5 kg of differently colored sweaters were placed in a Siemens Siewamat 3573 washing machine with a capacity of 5.5 kg of laundry and about 60 l of water. The sweaters were prewashed once at 40 ° C using a conventional heavy-duty detergent containing amylase. The fleet was then made of 1.2 kg of ground glass of the Miltopan® GB type (Pulcra / ES, particle size distribution: 75% <50 μm, 20% 50 to 100 μm, 5%> 100 μm) and 100 g of a preparation

35% by weight cellulase

15% by weight tallow fatty alcohol + 5 EO and

50% by weight sodium citrate / citric acid (1: 1)

admitted. The sweaters were treated at 50 ° C for 35 min and then rinsed twice. Afterwards, they had a pleasant soft feel and an even texture effect.

Example 2. Example 1 was repeated with a product which had a particle size distribution of 75% <50 μm, 20% 50 to 100 μm and 5%> 100 μm, and the glass recovered from the first treatment being used for the mechanical treatment of the fabrics was reinstated. After completion of the wash, the sweaters had a soft feel and textured effect like the pattern from Example 1.

Example 3. Example 2 was repeated and used for the mechanical treatment of the tissue ground glass, which had already been recovered a total of five times. In addition to the ground glass, a product of the following composition was used:

15% by weight cellulase

10% by weight tallow fatty alcohol + 5 EO and

15% by weight of zeolite A

60% by weight sodium citrate / citric acid (1: 1)

After completion of the process, these sweaters also had the same soft feel and texture effect as the pattern from Example 1.

Claims

claims

1. Waxing process for textiles, in which an aqueous liquor containing wholly or predominantly knitwear is

(a) 1 to 50 g / l ground silicon compounds and

(b) 0.5 to 4 g / l cellulases

- based on the volume of the wash liquor - treated.

2. The method according to claim 1, characterized in that knitwear made of cotton, lyocell, viscose or mixtures thereof is used.

3. Process according to claims 1 and 2, characterized in that ground silicates, sand, glass and / or diatomaceous earth are used as component (a).

4. Process according to claims 1 to 3, characterized in that silicon compounds are used which have a diameter in the range of 0.01 to 200 microns.

5. Process according to claims 1 to 4, characterized in that acidic cellulases are used as component (b) which have an optimum activity at a pH in the range from 4.5 to 5.5.

6. Process according to claims 1 to 5, characterized in that a liquor ratio of knitwear: water is set from 1:10 to 1:30 parts by weight.

7. Process according to claims 1 to 6, characterized in that zeolites of the formula (I) are also used,

M2zO * Al2θ3 * x Siθ2 * y H ₂ 0 (I)

in which M stands for an alkali or alkaline earth metal of valence z, x for numbers from 1, 8 to 12 and y for numbers from 0 to 8. Process according to claims 1 to 7, characterized in that fatty alcohol polyglycol ethers of the formula (II) are also used,

R ¹ 0 (CH ₂ CH ₂ 0) _n H (II)

in which R ^{1 is} a linear or branched alkyl radical having 12 to 22 carbon atoms and n is a number from 2 to 50.