Background of the Invention <BR> <BR> Dyed cellulosic textiles are commonly used in making a large variety of products, e. g. , denim jeans. One class of denim are garments and articles which are characterized as overdyed denim. These products are produced by subjecting a warp dyed denim with undyed fill yarn to a further dyeing step. The further dyeing step imparts to the denim a particular color tint which is introduced by the dye, which is especially evident from the fill yarn. This further dyeing step acts to primarily dye the fill yarn of the desized denim but also imparts some degree of dyeing to the previously dyed warp yarn. Producing overdyed denim garments and articles requires that the desized denim is contacted in a dye bath with a selected dye under appropriate conditions. For such dyeing operations, direct dyes and fiber reactive dyes as defined in the Colour Index are generally used. The denim containing products are contacted with the direct dye in a bath under conditions which are dictated by the direct dye selected. These conditions are generally at a temperature in the range of 85°-95°C, for a period of about 0.5-2. 5 hours in an aqueous bath which typically further includes an effective amount of a salt generally to provide a bath concentration of 5-40 g of salt per liter of bath. Typical dye baths have a pH in the range of 7- 8. 5.

Summary of the Invention The present invention relates to methods for enzymatic decolorization (bleaching) and dyeing, preferably overdyeing, of a textile material in a single bath process, i. e. , in which the bleaching and dyeing, preferably over dyeing, processes are preformed in the same aqueous bath.

In one embodiment of the present invention, a dyed, preferably an overdyed, textile material, such as, a fabric or other cellulosic material, is prepared by treating the fabric or other cellulosic material in an aqueous bath with a bleaching system comprising (i) a hydrogen peroxide source and at least one enzyme exhibiting peroxidase activity and/or (ii) at least one enzyme exhibiting oxidase activity and an oxygen source, and adding to the same aqueous bath at least one dye precursor and/or preformed dye in an amount effective for dyeing, preferably overdyeing, the fabric or other cellulosic material. The dye precursor is preferably added sequentially, after the bleaching step. In an alternative embodiment, a preformed dye is added sequentially using a dye that is not oxidized by the enzyme system employed.

In another preferred embodiment, a textile material, such as, an dyed, preferably, overdyed, fabric or other cellulosic material, is prepared by treating the fabric or other cellulosic material in an aqueous bath with a bleaching system comprising (i) a hydrogen peroxide source and at least one enzyme exhibiting peroxidase activity and/or (ii) at least one enzyme exhibiting oxidase activity and an oxygen source, and adding to the same aqueous bath at least one dye precursor and/or preformed dye and an additional amount of (i) and/or (ii) in amounts effective for dyeing, preferably, overdyeing, the fabric or other cellulosic material.

Detailed Description of the Invention Accordingly, the present invention relates to methods for enzymatic decolorization (bleaching) and dyeing, preferably, overdyeing, of a textile material, such as a fabric or other cellulosic material, in which the bleaching and overdyeing processes are preformed sequentially or alternatively simultaneously in the same aqueous bath.

Dyed Fabric or Article The fabric or article is preferably a textile, yarn, fiber, garment or film. The textile, yarn, fiber, garment or film may also be dyed. The fabric or article may be made of cotton, diacetate, flax, fur, hide, linen, lyocel, polyacrylic, polyamide, polyester, polyurea (such as Spandex), ramie, rayon, tencel, triacetate, viscose or wool. Preferably, the fabric or article is a cellulosic or cellulose-containing fabric or article.

The fabrics and articles may be constructed of a warp yarn, which is woven with a filing yarn.

Generally, the warp yarn is dyed a color such as indigo, blue, black or other color while the filing yarn is generally an unbleached or white yarn. Dyed fabrics and articles where both the warp yarn and the filling yarn are dyed may also be used.

In a preferred embodiment, the fabric or article is a dyed fabric or article, e. g. , denim.

Enzyme The second component contained in the bleaching and overdyeing bath used in the methods of the present invention is (a) a hydrogen peroxide source and at least one enzyme exhibiting peroxidase activity and/or (b) at least one enzyme exhibiting oxidase activity on the compound.

Enzymes exhibiting peroxidase activity include, but are not limited to, peroxidase (EC 1.11. 1.7) and haloperoxidase, e. g., chloro- (EC 1.11. 1.10), bromo- (EC 1. 11. 1) and iodoperoxidase (EC 1. 11. 1.8).

Enzymes exhibiting oxidase activity include, but are not limited to, bilirubin oxidase (EC 1.3. 3.5), catechol oxidase (EC 1.10. 3.1), laccase (EC 1.10. 3.2), o-aminophenol oxidase (EC 1.10. 3.4), and polyphenol oxidase (EC 1.10. 3.2). Preferably, the enzyme is a laccase obtained from a genus selected from the group consisting of Aspergillus, Botrytis, Collybia, Fomes, Lentinus, Myceliophthora, Neurospora, Pleurotus, Podospora, Polyporus, Rhizoctonia, Scytalidium, and Trametes. In a more preferred embodiment, the laccase is obtained from a species selected from the group consisting of Coprinus cinereus, Humicola brevis var. thermoidea, Humicola brevispora, Humicola grisea var. thermoidea, Humicola insolens, and Humicola lanuginosa (also known as Thermomyces lanuginosus), Myceliophthora thermophila, Myceliophthora vellerea, Polyporuspinsitus, Rhizoctonia solani, Scytalidium indonesiacum, Scytalidium thermophila, and Torula thermophila. The laccase may be obtained from other species of Scytalidium, such as Scytalidium acidophilum, Scytalidium album, Scytalidium aurantiacum, Scytalidium circinatum, Scytalidium flaveobrunneum, Scytalidium hyalinum, Scytalidium lignicola, and Scytalidium uredinicolum. The laccase may be obtained from other species of Polyporus, such as Polyporus alveolaris, Polyporus arcularius, Polyporus australiensis, Polyporus badius, Polyporus biformis, Polyporus brumais, Polyporus ciliatus, Polyporus colensoi, Polyporus eucalyptorum, Polyporus meridionalis, Polyporus palustris, Polyporus rhizophilus, Polyporus rugulosus, Polyporus squamosus, Polyporus tuberaster, Polyporus tumulosus, Polyporus varius, and Polyporus zonatus. The laccase may also be obtained from Trametes, such as, Trametes versicolor and Trametes villosa Peroxidases which may be employed in the methods of the present invention may be isolated <BR> <BR> from and are producible by plants (e. g. , horseradish peroxidase) or microorganisms such as fungi or bacteria. Some preferred fungi include strains belonging to the subdivision Deuteromycotina, class Hyphomycetes, e. g., Arthromyces, Caldariomyces, Cladosporium, Dreschlera, Embellisia, Fusarium, Humicola, Myrothecium, Tricoderma, Ulocladium, or Verticillum, in particular, Arthromyces ramosus (FERM P-7754), Caldariomyces fumago, Dreschlera haloes, Embellisia alli, Fusarium oxysporum (DSM 2672), Humicola insolens, Myrothecium verrucana (IFO 6113), Trichoderma resii, Ulocladium chartarum, Verticillum alboatrum, and Verticillum dahlie. Other preferred fungi include strains belonging to the subdivision Basidiomycotina, class Basidiomycetes, e. g., Coprins, Coriolus, Phanerochaete, or Trametes, in particular Coprinus cinereus f. microsporus (IFO 8371), Coprins macrorhizus, Coriolus versicolor (e. g. , PR4 28-A) or Phanerochaete chrysosporium (e. g., NA-12). Further preferred fungi include strains belonging to the subdivision Zygomycotina, class Mycoraceae, e. g., Mucor or Rhizopus, in particular Mucor hiemalis.

Some preferred bacteria include strains of the order Actinomycetales, e. g., Streptomyces spheroids (ATCC 23965), Streptomyces thermoviolaceus (IFO 12382) or Streptoverticillum verticillium ssp. verticillium. Other preferred bacteria include Bacillus pumillus (ATCC 12905), Bacillus stearothermophilus, Pseudomonas fluorescens (NRRL B-11), Pseudomonaspurrocinia (ATCC 15958), Rhodobacter sphaeroides, Rhodomonas palustri, and Streptococcus lactis.

Methods of producing enzymes to be used according to the invention are described in the art, e. g. , FEBS Letters 1625, 173 (1), Applied and Environmental Microbiology, Feb. 1985, pp. 273- 278, Applied Microbiol. Biotechnol. 26, 1987, pp. 158-163, Biotechnology Letters 9 (5), 1987, pp.

357-360, Nature 326, 2 April 1987, FEBS Letters 4270, 209 (2), p. 321, EP 179 486, EP 200 565, GB 2 167 421, EP 171 074, and Aaric. Biol. Chem. 50 (1), 1986, p. 247.

Particularly preferred enzymes are those which are active at a pH in the range of about 2.5 to about 12.0, preferably in the range of about 4 to about 10, most preferably in the range of about 4.0 to about 7.0 and in the range of about 7.0 to about 10.0. Such enzymes may be isolated by screening for the relevant enzyme production by alkalophilic microorganisms, e. g. , using the ABTS assay described in R. E. Childs and W. G. Bardsley, Biochem. J. 145, 1975, pp. 93-103.

Other preferred enzymes, are those which exhibit a good thermostability as well as a good stability towards commonly used dyeing additives such as non-ionic, cationic, or anionic surfactants, cheating agents, salts, polymers, etc.

When the enzyme employed is a peroxidase, the water bath must contain a hydrogen peroxide <BR> <BR> source, e. g. , hydrogen peroxide itself. The hydrogen peroxide source may be added at the<BR> beginning or during the process, e. g. , in an amount in the range of 0.001-5 mM, preferably in the range 0.01-1 mM. One source of hydrogen peroxide includes precursors of hydrogen peroxide, <BR> <BR> e. g. , a perborate or a percarbonate. Another source of hydrogen peroxide includes enzymes which are able to convert molecular oxygen and an organic or inorganic substrate into hydrogen peroxide and the oxidized substrate, respectively. These enzymes produce only low levels of hydrogen peroxide, but they may be employed to great advantage in the process of the invention as the presence of peroxidase ensures an efficient utilization of the hydrogen peroxide produced. Examples of enzymes which are capable of producing hydrogen peroxide include, but are not limited to, glucose oxidase, urate oxidase, galactose oxidase, alcohol oxidase, amine oxidase, amino acid oxidase and cholesterol oxidase.

When the enzyme is an oxidase, a source of oxygen, such as air, must also be available.

Preferably a mediator for the enzyme (s) is used in the method. Any suitable mediator may be used. Suitable mediators for oxidase enzymes, and in particular, for laccase, include, for example, acetosyringon, methylsyringate, ethylsyringate, butylsyringate and laurylsyringate, 10- propionic acid-phenothiazine (PPT). Suitable mediators for peroxidase enzymes include, for, example, methylsyringate and PPT.

Dye Precursors The dye precursor (s) is added in the bath after decolorizing the fabric. Any suitable dye precursor may be employed in the present invention. Preferably, mono-, di-or polycyclic aromatic or heteroaromatic compounds are used in the methods of the present invention as dye precursors. Optionally, the mono-, di-or polycyclic aromatic or heteroaromatic compounds are substituted with one or more functional groups or substituents, wherein each functional group or substituent is selected from the group consisting of halogen ; sulfo ; sulfonato ; sulfamino ; sulfanyl ; amino; amido; nitro; azo; imino; carboxy; cyano; formyl ; hydroxy; halocarbonyl ; carbamoyl ; carbamidoyl ; phosphonato; phosphonyl ; C1 18-alkyl ; C1 18-alkenyl ; d-is-atkyny) ; C1 18-alkoxy ; C1 18-oxycarbonyl ; Ci-is-oxoaikyi ; C1 18-alkyl sulfanyl ; C1 18-alkyl sulfonyl ; C1 18-alkyl imino oramino which is substituted with one, two or three C1 18-alkyl groups; wherein each C1 18-alkyl, C1 18-alkenyl and d-ia-aikynyi group may be mono-, di or poly-substituted by any of the proceeding functional groups or substituents. Examples of such mono-, di-or polycyclic aromatic or heteroaromatic compounds include, but are not limited to, acridine, anthracene, azulene, benzene, benzofurane, benzothiazole, benzothiazoline, carboline, carbazole, cinnoline,

chromane, chromene, chrysene, fulvene, furan, imidazole, indazole, indene, indole, indoline, indolizine, isothiazole, isoquinoline, isoxazole, naphthalene, naphthylene, naphthylpyridine, oxazole, perylene, phenanthrene, phenazine, phtalizine, pteridine, purine, pyran, pyrazol, pyrene, pyridazine, pyridazone, pyridine, pyrimidine, pyrrole, quinazoline, quinoline, quinoxaline, sulfonyl, thiophene, and triazine, each of which are optionally substituted. Examples of such compounds include, but are not limited to, aromatic diamines, aminophenols, phenols and naphthols.

Examples of aromatic and heteroaromatic compounds for use in the present invention include, but are not limited to: 3, 4-diethoxyaniline, 2-methoxy-p-phenylenediamine, 1-amino4-b-methoxyethylamino-benzene (N-b-methoxyethylp-phenylenediamine), 1-amino-4-bis- (b-hydroxyethyl)-aminobenzene (N, N-bis- (b-hydroxyethyl)-p-phenylenediamine), 2-methyl-1, 3-diamino-benzene (2, 6-diaminotoluene), 2, 4-diaminotoluene, 2,6-diaminopyridine, 1-amino-4-sulfonato-benzene, 1-N-methylsulfonato-4-aminobenzene, 1-methyl-2-hydroxy-4-amino-benzene (3-aminoo-cresol), 1-methyl-2-hydroxy-4-b-hydroxyethylamino-benzene (2-hydroxy-4-b-hydroxyethylamino-toluene), 1-hydroxy-4-methylamino-benzene (p-methylaminophenol), 1-methoxy-2, 4-diamino-benzene (2, 4-diaminoanisole), 1-ethoxy-2, 3-diamino-benzene (2, 4-diaminophenetole), 1-b-hydroxyethyloxy-2, 4-diamino-benzene (2, 4-diaminophenoxyethanol), 1, 3-dihydroxy-2-methylbenzene (2-methylresorcinol), 1,2, 4-trihydroxybenzene, 1,2, 4-trihydroxy-5-methylbenzene (2, 4, 5-trihydroxytoluene), 2,3, 5-trihydroxytoluene, 4, 8-disulfonato-1-naphtol, 3-sulfonato-6-amino-1-naphtol (J acid), 6, 8-disulfonato-2-naphtol, 1, 4-Phenylenediamine, 2, 5-Diaminotoluene, 2-Chloro-1, 4-phenylenediamine, 2-Aminophenol, 3-Aminophenol, 4-Aminophenol, 1, 3-Phenylenediamine, 1-Naphthol, 2-Naphthol 4-Chlororesorcinol, 1,2, 3-benzenetriol (Pyrogallol), 1, 3-Benzenediol (Resorcinol), 1, 2-Benzenediol (Pyrocatechol), 2-Hydroxy-cinnamic acid, 3-Hydroxy-cinnamic acid, 4-Hydroxy-cinnamic acid, 2,3-diaminobenzoic acid, 2,4-diaminobenzoic acid, 3,4-diaminobenzoic acid, 3,5-diaminobenzoic acid, Methyl 2,3-diaminobenzoate, Ethyl 2,3-diaminobenzoate, Isopropyl 2,3-diaminobenzoate, Methyl 2,4-diaminobenzoate, Ethyl 2,4-diaminobenzoate, Isopropyl 2,4-diaminobenzoate, Methyl 3,4-diaminobenzoate, Ethyl 3,4-diaminobenzoate, Isopropyl 3,4-diaminobenzoate, Methyl 3,5-diaminobenzoate, Ethyl 3,5-diaminobenzoate, Isopropyl 3,5-diaminobenzoate, N, N-dimethyl-3, 4-diaminobenzoic acid amide, N, N-diethyl-3, 4-diaminobenzoic acid amide, N, N-dipropyl-3, 4-diaminobenzoic acid amide, N, N-dibutyl-3, 4-diaminobenzoic acid amide, 4-Chlo, ro-1-naphthol, N-Phenyl-p-phenylenediamine 3, 4-Dihydroxybenzaldehyde, Pyrrole, Pyrrole-2-isoimidazole, 1,2, 3-Triazole, Benzotriazole, Benzimidazole, Imidazole, Indole, 1-Amino-8-hydroxynaphthalene4-sulfonic acid (S acid),

4, 5-Dihydroxynapthaiene-2, 7-disulfonic acid (Chromotropic acid), Anthranilic acid, 4-Aminobenzoic acid (PABA), 2-Amino-8-naphthol-6-sulfonic acid (Gamma acid), 5-Amino-1-naphthol-3-sulfonic acid (M acid), 2-Naphthol-3, 6-disulfonic acid (R acid), 1-Amino-8-naphthol-2, 4-disulfonic acid (Chicago acid), 1-Naphthol-4-sulfonic acid (Neville-winther acid), Peri acid, N-Benzoyl J acid, N-Phenyl J acid, 1, 7-Cleves acid, 1, 6-Cleves acid, Bon acid, Naphthol AS, Disperse Black 9, Naphthol AS OL, Naphthol AS PH, Naphthol AS KB, NaphtholASBS, Naphthol AS D, Naphthol AS B1, Mordant Black 3 Cl 14640 (Eriochrome Blue Black B), 4-Amino-5-hydroxy-2, 6-Naphthalene Disulphonic acid (H acid), Fat Brown RR Solvent Brown 1 (Cl 11285), Hydroquinone, Mandelic Acid, Melamine, o-Nitrobenzaldehyde, 1, 5-Dihydroxynaphthalene, 2, 6-Dihydroxynaphthalene, 2, 3-Dihydroxynaphthalene, Benzylimidazole, 2, 3-Diaminonaphthalene, 1, 5-Diaminonaphthalene, 1, 8-Diaminonaphthalene, Salicylic acid, 3-aminosalicylic acid, 4-aminosalicylic acid, 5-aminosalicylic acid, Methyl-3-aminosalicylate, Methyl-4-aminosalicylate, Methyl-5-aminosalicylate, Ethyl-3-aminosalicylate, Ethyl-4-aminosalicylate, Ethyl-5-aminosalicylate, Propyl-3-aminosalicylat, Propyl-4-aminosalicylate, Propyl-5-aminosalicylate, Salicylic amide, 4-Aminothiophenol, 4-Hydroxythiophenol, Aniline, 4, 4'-Diaminodiphenylamine sulfate, 4-Phenylazoaniline, 4-Nitroaniline, N, N-Dimethyl-1, 4-phenylenediamine, N, N-Diethyl-1, 4-phenylenediamine, Disperse Orange 3, Disperse Yellow 9, Disperse Blue 1, N-Phenyl-1, 2-phenylenediamine, 6-Amino-2-naphthol, 3-Amino-2-naphthol, 5-Amino-1-naphthol, 1, 2-Phenylenediamine, 2-Aminopyrimidine, 4-Aminoquinaldine, 2-Nitroaniline, 3-Nitroaniline, 2-Chloroaniline, 3-Chloroaniline, 4-Chloroaniline, 4- (phenylazo) resorcinol (Sudan Orange G, Cl 11920), Sudan Red B, Cl 26110, Sudan Red 7B, Cl 26050, 4'-Aminoacetanilide, Alizarin, 1-Anthramine (1-Aminoanthracene), 1-Aminoanthraquinone, Anthraquinone, 2,6-Dihydroxyanthraquinone (Anthraflavic Acid), 1,5-Dihydroxyanthraquinone (Anthrarufin), 3-Amidopyridine (Nicotinamide), Pyridine-3-carboxylic acid (Nicotinic Acid), Mordant Yellow 1, Alizarin Yellow GG, Cl 14025, Coomassie Grey, Acid Black 48, Cl 65005, Palantine Fast Black WAN, Acid Black 52, Cl 15711, Palantine Chrome Black 6BN, Cl 15705, Eriochrome Blue Black R, Mordant Black 11, Eriochrome Black T, Naphthol Blue Black, Acid Black 1, Cl 20470,1, 4-Dihydroxyanthraquinone (Quinizarin), 4-Hydroxycoumarin, Umbelliferone, 7-Hydroxycoumarin, Esculetin 6,7-Dihydroxycoumarin, Coumarin, Chromotrope 2B Acid Red 176, Cl 1657, Chromotrope 2R Acid Red 29, Cl 16570, Chromotrope FB Acid Red 14, Cl 14720,2, 6-Dihydroxyisonicotinic acid, Citrazinic acid, 2, 5-Dichloroaniline, 2-Amino-4-chlorotoluene, 2-Nitro-4-chloroaniline, 2-Methoxy- 4-nitroaniline and p-Bromophenol.

More preferably, the dye precursors used in the present invention are N, N,-Diethyl-1, 4- phenylenediamine sulfate, 4, 4'-Diaminodiphenylamine sulfate, N-Phenyl-1, 4-phenylenediamine, N-Phenyl-1, 2-phenylenediamine, or 4-Hydroxycinnamic.

In another embodiment, the aromatic or heteroaromatic compound reacts with the dye already present on the fabric or article. In another preferred embodiment, the fabric or article contain one or more aromatic, e. g. , phenolic, compounds which enhance the binding of the dye precursor, such as, the mono-, di-or polycyclic aromatic or heteroaromatic compound to the fabric or article.

In addition to a dye precursor (s), suitable modifier compounds may also be employed to change the color produced on the fabric or other material. Although a dye precursor can also act as a "modifier compound", the term"modifier compound"is used herein to describe compounds that are not a direct or only a weak substrate for the oxidase or peroxidase, but which readily condense with the dye precursor compound to produce color. The dye precursor (s) and modifier compound (s) may be combined in a number of different ways to produce different colors and effects. For example, in the treatment of denim, the dye precursor (s) and modifier compound (s) may be used to obtain a"vintage"or"tinted"type effect on a desized and abraded denim.

Preferably, the modifier compound is a naphthol-type compound or a meta-substituted diamine or meta-substituted aminophenol. More preferably, suitable modifiers are Naphthol, 5-Amino-1- naphthol, 2-Naphtol, 2, 3-Dihydrozynaphthalene, and 2-Hydroxycinnamic acid.

The dye precursor is preferably added to the bath about 10 to about 40 minutes following the addition of the enzyme, depending on the dose of enzyme employed. In a preferred embodiment, no additional quantity of enzyme is added with the dye precursor. However, depending on the concentration of enzyme initially added to the system for decolorization, an additional amount of peroxidase and/or oxidase enzyme may be added with the dye precursorto complete the overdyeing process, as needed.

Alternatively, or in addition to a dye precursor, a preformed dye may be used. Preferably, the preformed dye is not oxidized by enzyme system.

The relative proportions of the constituents used in the process vary over a wide range and depend on the ultimate textile treatment effect desired. Variables to be considered include process conditions such as time, temperature and pH. These relative proportions may be determined by routine experimentation. In a preferred embodiment, the aqueous bath used in

the methods of the present invention preferably has a water/textile ratio in the range of about 5: 1 to about 200: 1, more preferably in the range of about 3: 1 to about 200: 1, more preferably 5: 1 to 20: 1. Preferably, the enzyme is present in an amount in the range of. 005 to 20 mg/ml, more preferably in the range of. 05 to 12 mg/ml. Preferably, a mono-, di-or polycyclic aromatic or heteroaromatic compound is added at a concentration in the range of. 005 to 20 mg/ml, more preferably in the range of. 5 to 5 mg/ml.

Preferably, the bleaching process is carried out for 10 to 50 min, more preferably 15 to 30 min.

Preferably the dyeing process is carried out for 5 to 60 min., more preferably 15 to 45. However, the time of the bleaching process and dyeing process are determined based on a number of factors including, for example, the concentration of the enzyme, the concentration and type of dye precursor, and the extent of shade desired, and can be determined using routine experimentation.

The aqueous bath may further comprise conventional constituents, e. g., wetting agents, suspension agents, dispersants, surfactants, leveling agents, and buffering agents. For example, the dye liquor may further comprise a mono-or divalent ion which includes, but is not limited to, sodium, potassium, calcium and magnesium ions (0-3 M, preferably 25 mM-1 M), a polymer which includes, but is not limited to, polyvinylpyrrolidone, polyvinylalcohol, polyaspartate, polyvinylamide, polyethelene oxide (0-50 g/l, preferably 1-500 mg/1) and a surfactant (10 mg-5 g/I). Examples of such surfactants are anionic surfactants such as carboxylates, for example, a metal carboxylate of a long chain fatty acid; N-acylsarcosinates ; mono or di-esters of phosphoric acid with fatty alcohol ethoxylates or salts of such esters; fatty alcohol sulphates such as sodium dodecyl sulphate, sodium octadecyl sulphate or sodium cetyl sulphate ; ethoxylated fatty alcohol sulphates; ethoxylated alkylphenol sulphates ; lignin sulphonates ; petroleum sulphonates ; alkyl aryl sulphonates such as alkyl-benzene sulphonates or lower alkylnaphthalene sulphonates, e. g., butyl-naphthalene sulphonate ; salts or sulphonated naphthalene-formaldehyde condensates; salts of sulphonated phenol-formaldehyde condensates; or more complex <BR> <BR> sulphonates such as amide sulphonates, e. g. , the sulphonated condensation product of oleic<BR> acid and N-methyl taurine orthe dialkyl sulphosuccinates, e. g. , the sodium sulphonate ordioctyl succinate. Further examples of such surfactants are non-ionic surfactants such as condensation products of fatty acid esters, fatty alcohols, fatty acid amides or fatty-alkyl-or alkenyl-substituted phenols with ethylene oxide, block copolymers of ethylene oxide and propylene oxide, acetylenic glycols such as 2,4, 7, 9-tetraethyl-5-decyn-4, 7-diol, or ethoxylated acetylenic glycols. Further examples of such surfactants are cationic surfactants such as aliphatic mono-, di-, or polyamines such as acetates, naphthenates or oleates ; oxygen-containing amines such as an amine oxide

of polyoxyethylene alkylamine ; amide-linked amines prepared by the condensation of a carboxylic acid with a di-or polyamine ; or quaternary ammonium salts.

In the methods of the present invention, the treatment may be carried out at a temperature in the range of about 5 to about 100C, preferably in the range of about 35 to about 80°C, and more preferably in the range of about 35°C to 50°C or 50°C to about 80°C, and a pH in the range of about 2.5 to about 12, preferably between about 4 and about 10, more preferably in the range of about 4.0 to about 7.0 or in the range of about 7.0 to about 10.0. Preferably, a temperature and pH near the temperature and pH optima of the enzyme, respectively, are used.

Following treatment in the aqueous bath, the fabric or article may be rinsed with hot or cold water. One or more of the rinses may also include a scavenger for dye components which may have been freed or remain as residual products from the single bath process. The fabric or article also may be subjected to further conventional treatments steps, e. g. , finishing such as by treatment with softening, finishing and lubricating agents.

The invention is further illustrated by the following non-limiting example.

EXAMPLES MATERIALS Fabric 32 Burlington (sulfur bottom type) denim swatches (14cm x 18.3cm, 12g each), pre-desized and abraded according to standard protocols. Two swatches for each labomat beaker.

Enzymes/Chemicals : Mvceliophthora laccase 120 LAMU/g, Mvceliophthora laccase/methvl svrinaate Laccase cassava, 800 LAMU/g, Sodium acetate: buffer salts (targeting pH5.0), Non-ionic surfactant for overdyeing post wash.

Precursors/coualers for overdyeing : A. N, N-diethyl-p-phenylenediamine, B. 4, 4'-diaminodiphenylamine sulfate, C. N-phenyl-1, 2-phenylenediamine, D. 2,3-dihydroxy naphthalene, EQUIPMENT Labomat Type BFA Beaker Dyer, HunterLab Labscan XE Spectrophotometer, METHOD

Table 1 Precursor Laccase/MES t_accase/ME Beaker combinatio Laccase Laccase/MES Dose s t_dyeing/t_ n (lamu/ml) (Dosing) (owg) (min) (min) B1 A/B # All-in 1% 0 60/60 B2 A/B # All-in 3% 0 60/60 B3 A/B # All-in 5% 0 60/60 B4 A/B # Sequential 3% 30 60/90 B5 A/B Sequential 5% 30 60/90 B6 A/B 0.12 (solid) # # # 60 B7 A/B 0.36 (solid) # # # 60 B8 A/B 0.60 (solid) # # # 60 B9 A/B # # # # 60 B10 C/D # All-in 5% 0 60/60 B11 C/D # Sequential 5% 30 60/90 B12 C/D 0.60 (solid) # # # 60 B13 C/D # # # # 60 B14 # # Blank 1 % 30 0/30 B15 Blank 3% 30 0/30 B16 # # Blank 5% 30 0/30 Other process conditions for all trials are: 70°C, pH 5 (buffered), 10: 1LR, 55rpm In one trial, the solid precursor combination and laccase/methylsyringate (MES) were added directly to beaker and run for 60 minutes. In another trial, the laccase/methylsyringate was added to the beaker, and after 30min, the solid precursor combination was added to the beaker and continued to run for 60 minutes. The swatches were removed from the dye bath, excess dye squeezed off, and transfered into beakers pre-filled with 0. 1% nonionic surfactant NF (20: 1 LR) and run at 40°C for 15 minutes. The swatches were then rinsed thoroughly and air dryed.

Test/analysis A HunterLab Labscan Reflectometer was used to evaluate the color change expressed with L*a*b*--CIE L*a*b* system. 3 L* gives the change lightness ; 3 a* gives the change in green (3 a*<0) or red (3 a*>0) ; 3 b* gives the change in yellow (3 b*>0) or blue (3 b*<0). Each result was an average of four measurements. Color difference is calculated against the controls--- swatches that were treated with precursors only.

K/S values can also be obtained from the HunterLab Reflectometer. K/S is calculated from the Kubelka-Munk equation as follows : K/S= (1-R) 2/2R where: K = absorption coefficient, depending on the concentration of the colorant ; S = scattering coefficient, often caused only by the substrate being dyed; and R = reflectance factor (from 0 to 1).

This equation describes the relationship between reflection and the concentration of the colorants of the opaque reflecting samples. K/S denotes the change in color strength of the dyed swatches.

Table 2. Laccase Laccasex L*_Mean L* a*_Mean a* b*_Mean b* KjSa K/S Precursor Base Process MES Std Std Std combination (lamu/ml) ow Dev Dev Dev Dev A/B # Ali-inb 1% 14.76 0. 16 3.89 0. 18-4. 64 0. 4629. 820. 69 A/B # All-in 3% 13.31 0. 26 3.32 0. 05-3. 02 0. 2434. 001. 08 A/B # All-in 5% 13.56 0. 50 3.14 0.16-3. 32 0. 7133. 061. 60 A/B # Sequential'3% 22.20 0. 83 3.92 0.10-5. 58 0. 6014. 921. 07 A/B # Sequential 5% 22.59 0. 55 4.13 0.17-4. 94 0. 9014. 550. 72 0. 12 14.31 0. 34 3.43 0.11-3. 81 0. 4830. 741. 11 (solid) 1 0.36 13.98 0. 57 2.64 0. 12-2. 92 0. 7231. 091. 45 A/B (solid) # # 0.60 13.91 0. 33 2.41 0. 15-2. 12 0. 6830. 402. 01 A/B solid # # A/B (control) # # # 20.99 0. 56 2.26 0.07-9. 10 0. 2915. 640. 95. C/D # All-in 5% 17.22 0. 34 4.55 0.13-0. 76 0. 3023. 800. 73 C/D Sequential 5% 35.20 0. 34 3.82 1. 07-4. 68 1. 68 5. 21 0. 31 0.60 19.33 1.01 3.97 0.12-2. 07 0. 7718. 571. 96 C/D solid # # C/D (control 29.70 0. 47 0. 72 0. 45-12. 57 0.90 5.92 0. 40 Blank # # 1% 40. 78 1.11-2. 48 0.24-11. 79 0. 57 5. 21 0. 43 Blank # # 3% 43. 69 0. 69-2. 63 0. 16-10. 38 0. 4 4. 13 0. 23 Biank # # 5% 43.58 0. 83-2. 71 0. 13-10. 58 0. 644. 210. 28 Note: a. K/S values were measured at the maximum weight length (0,.) of a specific color : for A/B, %. x =530nm; for C/D, qTlax =495nm; for laccase/methyl syringate bleached denim (blank), q"aX=655nm. b. All-in : precursors and laccase/methylsyringate added together in the beginning of the treatment. c. Sequential: precursors added after 30min laccase/methyl syringate treatment.

Two pairs of precursors, A/B and C/D, as previously defined, were selected for this study to generate color on pre-abraded denim swatches by either all-in or sequential method. The color data and color strength values are given in Table 2 and Figure 1-2.

Color generation is illustrated in Figure 1 as del L*, del a* and del b*, calculated against those of the control (treated with precursors only). Figure 1 and 2 show that the all-in method, where laccase/methyl syringate and the dye precursor combination were dosed together in the beginning of the experiment, yielded similar color and color strength on

swatches treated with laccase/methylsyringate and those treated with laccase alone at equivalent dosages. This finding indicated that one-bath denim decolorization and overdyeing with a dye precursor did not occur simultaneously in all-in mode. Instead, only overdyeing of denim took place in this case.

The sequential method, where the precursor combination was added following a 30min laccase/methylsyringate treatment, generated color on pre-decolorized denim swatches, as evidenced by higher del a* (more red), higher del b* (more yellow), and lower del L* (darker), compared to those treated with laccase/methylsyringate only (Figure 1). The color strength values of those by sequential method are generally lower and lightness (L*) higher than those by all-in method. This was largely attributed to less amount of indigo remaining on the fabric surface after the decolorization stage (Figure 2).