A METHOD OF OBTAINING A CELLULOSIC TEXTILE FABRIC WITH REDUCED TENDENCY TO PILLING FORMATION

Abstract: A method for obtaining a cellulosic textile fabric having a strongly reduced tendency to pilling formation, preferably corresponding to a pilling note of at least 4, more preferably of at least 4.5, which method comprises treating the fabric with a cellulase capable of performing a partial hydrolysis of the fibre surface corresponding to a < 2 % weight loss based on the untreated cellulosic textile fabric. The cellulase is preferably a 43 kD endoglucanase derived from or producible by Humicola insolens, DSM 1800, SEQ ID NO:1, or a functional analogue of said cellulase such as a variant which is modified by substitution of one or more amino acid residues in one or more of the positions 8, 55, 58, 62, 67, 132, 147, 162, 221, 222, 223, 280; or modified by truncation, preferably genetically truncation, at any position from position 213.

Description: A METHOD OF OBTAINING A CELLULOSIC TEXTILE FABRIC WITH REDU¬ CED TENDENCY TO PILLING FORMATION The present invention relates to a method for obtaining a cellulosic textile fabric having a strongly reduced tendency to pilling formation. More specifically, the invention rela¬ tes to a method wherein the cellulosic textile fabric is sub¬ jected to an enzymatic treatment with a cellulase without substantial weight loss. BACKGROUND OF THE INVENTION Without the application of finishing components, most cotton fabrics and cotton blend fabrics have a handle appearance that is rather hard and stiff. The fabric surface also is not smooth because small fuzzy microfibrils protrude from it. In addition, after a relatively short period of wear, pilling appears on the fabric surface thereby giving it an unappea¬ ling, worn look. A known method for obtaining a soft and smooth fabric is to subject cellulosic fabrics to treatment by cellulolytic en¬ zymes during their manufacture. This treatment is known as Bio-Polishing (hereinafter denoted biopolishing) , cf. Bazin j . and Sasserod, S . : Enzymatic Bio-Polishing of Cellulosic Fabric, Paper presented on October 25th, 1991, at "5βeme Con- gres de 1 ' Association des Chimistes de 1 ' Industrie Textile" , Mulhouse, France, which is hereby incorporated by reference. Biopolishing is a specific treatment of the yarn surface which improves fabric quality with respect to handle and ap¬ pearance without loss of fabric wettability. The most impor¬ tant effects of biopolishing can be characterised by less fuzz and pilling, increased gloss/luster, improved fabric handle, increased durable softness and improved water absor- bency. Biopolishing usually takes place in the wet processing of the manufacture of knitted and woven fabrics. Wet processing com¬ prises such steps as e.g. desizing, scouring, bleaching, washing, dying/printing and finishing. During each of these steps, the fabric can be subjected to mechanical action. However, since the cellulolytic enzymes catalyse hydrolysis of the cellulosic fibre surface, the enzymatic action will eventually result in a weight loss of fibre or fabric. Even though the biopolishing is carried out in such a way so as to obtain a controlled, partial hydrolysis of the fibre surface, a proper polishing effect without excessive loss of fabric strength has hitherto been obtained at a weight loss of fa¬ bric of 3-5 w/w%. Such a weight loss is undesirable for the textile industry and, for economical reasons, makes the biop¬ olishing process less desirable. Thus, it is the object of the present invention to provide a method for obtaining a cellulosic textile fabric with strong¬ ly reduced tendency to pilling formation but without substan- tial weight loss of fabric. SUMMARY OF THE INVENTION Surprisingly, it has been found that it is possible to obtain a cellulosic textile fabric having a strongly reduced tenden¬ cy to pilling formation at a significantly reduced weight loss by subjecting the fabric to a biopolishing process, pre¬ ferably using monocomponent cellulases. Accordingly, the method of the invention comprises treating a cellulose-fibre-containing textile fabric with a cellulase capable of performing a partial hydrolysis of the fibre sur- face corresponding to a weight loss of less than 2 w/w%, ba- sed on the untreated cellulosic textile fabric, or correspon¬ ding to a weight loss of less than about 2%, calculated as the difference, in terms of percentage, of the weight loss of the cellulase treated textile fabric and the weight loss of the textile fabric treated without cellulase (blank) . DETAILED DESCRIPTION OF THE INVENTION The fabric In the present context, the terms "cellulosic textile fabric" and "cellulose-fibre-containing textile fabric" are intended to indicate any type of fabric, in particular woven or knit¬ ted fabric, prepared from a cellulose-containing material, containing cellulose or cellulose derivatives, e.g. from wood pulp, and cotton. Also, in the present context, the term "fa¬ bric" is intended to include garments and other types of pro- cessed fabrics. Examples of cellulosic textile fabric is cot¬ ton, viscose (rayon); lyocell; flax (linen); all blends of viscose, cotton or lyocell with other fibers such as polye¬ ster; viscose/cotton blends, lyocell/cotton blends, viscose/- wool blends, lyocell/wool blends, cotton/wool blends; flax (linen) , ramie and other fabrics based on cellulose fibers, including all blends of cellulosic fibers with other fibers such as wool, polyamide, acrylic and polyester fibers, e.g. viscose/cotton/polyester blends, wool/cotton/polyester blends, flax/cotton blends etc. In the present context, the term "strongly reduced tendency to pilling formation" is intended to mean a permanent (and excellent) resistance to formation of pills on the surface of the treated (biopolished) fabric surface in comparison with fabric which has not been subjected to the method of the pre- sent invention. The tendency to pilling formation may be te¬ sted according to the Swiss norm SN 198525, published in 1990 by Schweizerische Nor en-Vereinigung, Kirchenweg 4, Postfach, CH-8032 Zurich, Switzerland, which describes a test of pil- ling-resistance for textiles which in turn is based on the Swiss norms SNV 95 150 (Textiles - Standard climatic condi¬ tions and test conditions for the physical tests under stan- dard climate conditions) and SN 198 529 (Testing of textil¬ es - "Scheuerfestigkeit" - Martindale method) . The results of the test is expressed in terms of "pilling notes" which is a rating on a scale from pilling note 1 (heavy pill formation) to pilling note 5 (no or very little pill formation) , allo- wing pilling notes. In a preferred embodiment of the present invention, the met¬ hod provides a textile fabric preferably having a pilling note of at least 4, more preferably of at least 4.5, especi¬ ally of 5, measured according to SN 198525 (1990). In another preferred embodiment, the method of the invention provides a textile fabric having rating which is at least 1, preferably at least 2 , especially at least 3, pilling note(s) higher than of the corrsponding untreated textile fabric; the absolute pilling notes being measured according to SN 198525 (1990) . According to the method of the invention, the partial hydro¬ lysis of the fibre surface corresponds to a weight loss of less than about 2 w/w%, preferably a weight loss of less than about 1.8 w/w%, more preferably of less than about 1.5 w/w%. The weight loss is determined under controlled conditions, i.e. according to SNV 95150, vide supra . The weight loss is expressed as the difference, in terms of percentage, of the weight loss of the cellulase treated textile fabric and the weight loss of the textile fabric treated without cellulase (blank) . The process As mentioned above, cellulase treatment of the fabric may be carried out simultaneously with other fabric manufacturing procedures, e.g. desizing, or after the bleaching of the fa¬ bric. It is to be understood that the method of the invention can be carried out in any conventional wet textile processing step, preferably after the desizing or bleaching of the tex¬ tile fabric, either simultanously with a conventional (well- known) process step or as an additional process step. The method will typically be accomplished in high-speed circular systems such as jet-overflow dyeing machines, high-speed win¬ ches and jiggers. An example of a useful High-speed system is the "Aero 1000" manufactured by Biancalani, Italy. Alternati¬ vely, the method can be accomplished in a two-step biopolish- ing process, e.g. as disclosed in the International Patent Application published as WO 93/20278, wherein the first step is a separate cellulase treatment which is carried out essen¬ tially without mechanical treatment, and followed by a second step wherein the fabric is subjected to a mechanical treat- ment. This cellulase treatment can be carried out in a J-Box, on a Pad-Roll or in a Pad-Bath. Cellulase treatment according to the present invention and desizing are reconcilable processes that can be conducted at the same conditions, i.e. pH, temperature, dosage/time ratio, etc. By performing these processes simultaneously, the over¬ all fabric manufacturing process becomes shortened. Such time saving arrangements are a major benefit of the process of the invention. Enzyme dosage greatly depends on the enzyme reaction time, i.e. a relatively short enzymatic reaction time necessitates a relatively increased enzyme dosage, and vice versa. In ge¬ neral, enzyme dosage may be stipulated in accordance with the reaction time available. In this way cellulase treatment of the fabric according to the present invention can be brought into conformity with e.g. the desizing conditions, if for instance these two reactions are to be carried out simultane¬ ously. An enzyme dosage/time ratio similar to what is known from conventional biopolishing may be used. Preferred enzyme do¬ sages are from about 100 to about 100,000 ECU/kg fabric, more preferably from about 500 to about 20,000 ECU/kg fabric, especially from about 1000 to about 5,000 ECU/kg fabric. Typically, the reaction time is from about 10 minutes to about 4 hours, preferably from about 20 minutes to about 2 hours but the reaction can be carried out for any period of time between about 1 minute and about 24 hours, in dependence of the specific type of processing equipment. The method of the invention may be carried out in the presen- ce of certain components which can be added to the cellulase, i.e. the formulated cellulase composition, or separately to the wash liquor wherein the enzyme treatment takes place. Examples of such components include a stabilizer, a wetting agent, a buffer and a dispersing agent. The stabilizer may be an agent stabilizing the cellulolytic enzyme. The wetting agent serves to improve the wettability of the fibre whereby a rapid and even desizing may be obtained. The wetting agent is preferably of an oxidation stable type. The buffer may suitably be a phosphate, borate, citrate, ace- tate, adipate, triethanolamine, monoethanolamine, diethanola- mine, carbonate (especially alkali metal or alkaline earth metal, in particular sodium or potassium carbonate, or ammo¬ nium and HC1 salts) , diamine, especially diaminoethane, imi- dazole, or a ino acid buffer. Preferably, the buffer is a mono-, di-, or triethanolamine buffer. The dispersing agent may suitably be selected from nonionic. anionic, cationic, ampholytic or zwitterionic surfactants. More specifically, the dispersing agent may be selected from carboxymethylcellulose, hydroxypropylcellulose, alkyl aryl sulphonates, long-chain alcohol sulphates (primary and secon- dary alkyl sulphates) , sulphonated olefins, sulphated monog- lycerides, sulphated ethers, sulphosuccinates, sulphonated methyl ethers, alkane sulphonates, phosphate esters, alkyl isothionates, acyl sarcosides, alkyl taurides, fluorosurfac- tants, fatty alcohol and alkylphenol condensates, fatty acid condensates, condensates of ethylene oxide with an a ine, condensates of ethylene oxide with an amide, block polymers (polyethylene glycol, polypropylene glycol, ethylene diamine condensed with ethylene or propylene oxide) , sucrose esters, sorbitan esters, alkyloamides, fatty amine oxides, ethoxyla- ted monoamines, ethoxylated diamines, ethoxylated polyamines, ethoxylated amine polymers and mixtures thereof. Preferably, the dispersing agent is an ethoxylated fatty acid ester or a nonylphenyl polyethyleneglycol ether. Further, the method of the invention may be carried out in the presence of a conventional antiredepostion agent, e.g. polymeric agents such as polyvinylpyrrolidone (PVP) , carboxy¬ methylcellulose (CMC) , and polyacrylates. The enzyme In the present context, the term "cellulase" or "cellulolytic enzyme" refers to an enzyme which catalyses the degradation of cellulose to glucose, cellobiose, triose and other cello- oligosaccharides. In the present context the term "enzyme" or "cellulase enzy¬ me" is understood to include a mature protein or a precursor form thereof as well to a functional fragment thereof which essentially has the activity of the full-length enzyme. Fur¬ thermore, the term "enzyme" is intended to include homologues or analogues of said enzyme. Such homologues comprise an ami¬ no acid sequence exhibiting a degree of identity of at least 60% with the amino acid sequence of the parent enzyme, i.e. the parent cellulase. The degree of identity may be determi- ned by conventional methods, see for instance, Altshul et al., Bull. Math. Bio. 48; 603-616, 1986, and Henikoff and Henikoff, Proc. Natl. Acad. Sci. USA 89; 10915-10919, 1992. Briefly, two amino acid sequences are aligned to optimize the alignment scores using a gap opening penalty of 10, a gap extension penalty of 1, and the "blosum 62" scoring matrix of Henikoff and Henikoff, supra. Alternatively, the homologue or analogue of the enzyme may be one encoded by a nucleotide sequence hybridizing with an oli- gonucleotide probe prepared on the basis of the nucleotide sequence or an amino acid sequence under the following condi¬ tions: presoaking in 5 X SSC and prehydbridizing for 1 hr. at about 40"C in a solution of 20% formamide, 5 X Denhardt's solution, 50 mM sodium phosphate, pH 6.8, and 50 μg denatured sonicated calf thymus DNA, followed by hybridization in the same solution supplemented with 100 μM ATP for 18 hrs. at about 40 * C, followed by a wash in 0.4 X SSC at a temperature of about 45 * C. Molecules to which the oligonucleotide probe hybridizes under these conditions are detected using standard detection pro- cedures (e.g. Southern blotting) . Homologues of the present enzyme may have one or more amino acid substitutions, deletions or additions. These changes are preferably of a minor nature, that is conservative amino acid substitutions that do not significantly affect the folding or activity of the protein, small deletions, typically of one to about 30 amino acids; small amino- or carboxyl-terminal ex¬ tensions, such as an amino-terminal methionine residue, a small linker peptide of up to about 20-25 residues, or a small extension that facilitates purification, such as a po- ly-histidine tract, an antigenic epitope or a binding domain. See in general Ford et al. , Protein Expression and Purifica¬ tion 2.: 95-107, 1991. Examples of conservative substitutions are within the group of basic amino acids (such as arginine, lysine, histidine) , acidic amino acids (such as glutamic acid and aspartic acid) , polar amino acids (such as glutamine and asparagine) , hydrophobic amino acids (such as leucine, iso- leucine, valine) , aromatic amino acids (such as phenylalani- ne, tryptophan, tyrosine) and small amino acids (such as gly- cine, alanine, serine, threonine, methionine) . It will be apparent to persons skilled in the art that such substitutions can be made outside the regions critical to the function of the molecule and still result in an active enzy¬ me. Amino acids essential to the activity of the enzyme of the invention, and therefore preferably not subject to sub¬ stitution, may be identified according to procedures known in the art, such as site-directed mutagenesis or alanine-scan- ning mutagenesis (Cunningham and Wells, Science 244. 1081- 1085, 1989). In the latter technique mutations are introdu- ced at every residue in the molecule, and the resultant mu¬ tant molecules are tested for cellulolytic activity to iden¬ tify amino acid residues that are critical to the activity of the molecule. Sites of ligand-receptor interaction can also be determined by analysis of crystal structure as determined by such techniques as nuclear magnetic resonance, crystallo¬ graphy or photoaffinity labelling. See, for example, de Vos et al., Science 255: 306-312, 1992; Smith et al., J. Mol. Biol. 224: 899-904, 1992; Wlodaver et al., FEBS Lett. 309: 59-64, 1992. The homologue may be an allelic variant, i.e. an alternative form of a gene that arises through mutation, or an altered enzyme encoded by the mutated gene, but having substantially the same activity as the enzyme of the invention. Hence muta¬ tions can be silent (no change in the encoded enzyme) or may encode enzymes having altered amino acid sequence. The homologue of the present enzyme may also be a genus or species homologue, i.e. an enzyme with a similar activity derived from another species. A homologue of the enzyme may be isolated by preparing a gen- omic or cDNA library of a cell of the species in question, and screening for DNA sequences coding for all or part of the homologue by using synthetic oligonucleotide probes in accor¬ dance with standard techniques, e.g. as described by Sambrook et al.. Molecular Cloning:A Laboratory Manual. 2nd. Ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, 1989, or by means of polymerase chain reaction (PCR) using specific primers as described by Sambrook et al., supra. Preferably, the cellulolytic enzyme to be used in the method of the invention is a monocomponent (recombinant) cellulase, i.e. a cellulase essentially free from other proteins or cel¬ lulase proteins. A recombinant cellulase component may be cloned and expressed according to standard techniques conven¬ tional to the skilled person. In a preferred embodiment of the invention, the cellulase to be used in the method is an endoglucanase (EC 3.2.1.4), pre¬ ferably a monocomponent (recombinant) endoglucanase. Preferably, the cellulase is a microbial cellulase, more pre¬ ferably a bacterial or fungal cellulase. Examples of bac¬ terial cellulases are cellulases derived from or producible by bacteria from the group of genera consisting of Pseudomo- nas or Bacillus lautus . The cellulase or endoglucanase may be an acid, a neutral of an alkaline cellulase or endoglucanase, i.e. exhibiting maxi¬ mum cellulolytic activity in the acid, neutral of alkaline range, respectively. Accordingly, a useful cellulase is an acid cellulase, pre- ferably a fungal acid cellulase, more preferably a fungal acid cellulase enzyme with substantial cellulolytic activity at acidic conditions which is derived from or producible by fungi from the group of genera consisting of Trichoderma, Actinomyces, Myrothecium, Aspergillus, and Botrytis . A preferred useful acid cellulase is derived from or produ¬ cible by fungi from the group of species consisting of Tri¬ choderma viride, Trichoderma reesei , Trichoderma longibrachi- atum , Myrothecium verrucaria , Aspergillus niger, Aspergillus oryzae , and Botrytis cinerea . Another useful cellulase or endoglucanase is a neutral or alkaline cellulase, preferably a fungal neutral or alkaline cellulase, more preferably a fungal alkaline cellulase or endoglucanase with substantial cellulolytic activity at alka- line conditions which is derived from or producible by fungi from the group of genera consisting of Aspergillus, Penicil- lium, Myceliophthora, Humicola, Irpex, Fusarium, Stachy- botrys, Scopulariopsis , Chaetomium, Mycogone, Verticillium, Myrothecium, Papulospora, Gliocladium, Cephalosporium and Acremonium . A preferred alkaline cellulase is derived from or producible by fungi from the group of species consisting of Humicola insolens , Fusarium oxysporum, Myceliopthora thermophile, or Cephalosporium sp. , preferably from the group of species con- sisting of Humicola insolens , DSM 1800, Fusarium oxysporum, DSM 2672, Myceliopthora thermophile, CBS 117.65, or Cephalo¬ sporium sp . , RYM-202. A preferred example of a native or parent cellulase is an alkaline endoglucanase which is immunologically reactive with an antibody raised against a highly purified ~ 43kD endogluca¬ nase derived from Humicola insolens , DSM 1800, or which is a derivative of the ~ 43kD endoglucanase exhibiting cellulase activity. A preferred endoglucanase component has the amino acid sequence enclosed as SEQ ID No. 1 which is also disclo¬ sed in the International Patent Application published as WO 91/17243, SEQ ID#2, which is hereby incorporated by referen¬ ce. Another preferred endoglucanase component is the core enzyme corresponding to the amino acid sequence enclosed as SEQ ID No. 1, but having the amino acid sequence correspon¬ ding to position 1-213, i.e. truncated at position 213. It is contemplated that other useful endoglucanases are enzymes having amino acid sequences corresponding to the amino acid sequence enclosed as SEQ ID No. 1, but which are truncated, preferably genetically truncated, at any position between position 213 and position 247 of the SEQ ID No. 1, i.e. ha¬ ving an amino acid sequence consisting of between 213 and 247 amino acid residues. Other examples of useful cellulases are variants having, as a parent cellulase, a cellulase of fungal origin, e.g. a cellu¬ lase derivable from a strain of the fungal genus Humicola , Trichoderma or Fusarium. For instance, the parent cellulase may be derivable from a strain of the fungal species H. inso- lens, Trichoderma reesei or F. oxysporum, preferably the ~ 43kD endoglucanase derived from Humicola insolens, DSM 1800, or is a functional analogue of any of said parent cellulases which i) comprises an amino acid sequence being at least 60% homo- logous with the amino acid sequence of the parent cellulase, ii) reacts with an antibody raised against the parent cellu¬ lase, and/or iii) is encoded by a DNA sequence which hybridizes with the same probe as a DNA sequence encoding the parent cellulase. Property i) of the analogue is intended to indicate the deg¬ ree of identity between the analogue and the parent cellulase indicating a derivation of the first sequence from the sec¬ ond. In particular, a polypeptide is considered to be homolo¬ gous to the parent cellulase if a comparison of the respect- ive amino acid sequences reveals an identity of greater than about 60%, such as above 70%, 80%, 85%, 90% or even 95%. Sequence comparisons can be performed via known algorithms, such as the one described by Lipman and Pearson (1985) . The additional properties ii) and iii) of the analogue of the parent cellulase may be determined as follows: Property ii) , i.e. the immunological cross reactivity, may be assayed using an antibody raised against or reactive with at least one epitope of the parent cellulase. The antibody, which may either be monoclonal or polyclonal, may be produced by methods known in the art, e.g. as described by Hudson et al., 1989. The immunological cross-reactivity may be determi¬ ned using assays known in the art, examples of which are We¬ stern Blotting or radial immunodiffusion assay, e.g. as desc¬ ribed by Hudson et al., 1989. The oligonucleotide probe used in the characterization of the analogue in accordance with property iii) defined above, may suitably be prepared on the basis of the full or partial nu¬ cleotide or amino acid sequence of the parent cellulase. The hybridization may be carried out under any suitable condi- tions allowing the DNA sequences to hybridize. For instance, such conditions are hybridization under specified conditions, e.g. involving presoaking in 5xSSC and prehybridizing for lh at ~40°C in a solution of 20% formamide, 5xDenhardt's sol¬ ution, 50mM sodium phosphate, pH 6.8, and 50μg of denatured sonicated calf thymus DNA, followed by hybridization in the same solution supplemented with lOOμM ATP for 18h at -40°C, or other methods described by e.g. Sambrook et al., 1989. Examples of useful cellulase variants are variants of the 43 kD endoglucanase derived from or producible by Humicola inso- lens , DSM 1800, SEQ ID N0:1, modified by substitution of one or more amino acid residues in one or more of the positions 8, 55, 58, 62, 67, 132, 147, 162, 221, 222, 223, 280; and optionally further modified by truncation, preferably geneti- cally truncation, at any position from position 213. Preferred cellulase variants are variants of the 43 kD endog¬ lucanase derived from or producible by Humicola insolens , DSM 1800, SEQ ID NO:l, modified by substitution of one or more 5 amino acid residues as follows: Y8F S55E/D D58A/S/N W62E 10 D67R/N F132A/D/E/G Y147S A162P V221S 15 N222S Q223T Y280F. Surprisingly, it has been found that, in case of using an alkaline endoglucanase such as the 43 D H. insolens , DSM 201800, endoglucanase or the mentioned modified variants there¬ of, it may be advantageous to carry out the method of the present invention at a pH below about 9, preferably at a pH below 6, more preferably at a pH of from about 4.5 to about 5.5, especially at a pH of about 5.0. 25 In the context of this invention, cellulase activity can be expressed in ECU. Cellulolytic enzymes hydrolyse CMC, thereby increasing the viscosity of the incubation mixture. The re¬ sulting reduction in viscosity may be determined by a vibra¬ tion viscosimeter (e.g. MIVI 3000 from Sofraser, France) . 30 Determination of the cellulolytic activity, measured in terms of ECU, may be determined according to the following analysis method (assay) : The ECU assay quantifies the amount of cata- lytic activity present in the sample by measuring the ability of the sample to reduce the viscosity of a solution of car- boxy-methylcellulose (CMC) . The assay is carried out at 40°C; pH 7.5; 0.1M phosphate buffer; time 30 min; using a relative enzyme standard for reducing the viscosity of the CMC(car- boxymethylcellulose Hercules 7 LFD) substrate; enzyme concen¬ tration approx. 0.15 ECU/ml. The arch standard is defined to 8200 ECU/g. Although the useful cellulase may be used as such in the met- hod of the present invention, it is preferred that it is for¬ mulated into a suitable composition. Thus, the useful cellu¬ lase may be used in the form of a granulate, preferably a non-dusting granulate, a liquid, in particular a stabilized liquid, a slurry, or in a protected form. Dust free granu¬ lates may be produced, e.g. as disclosed in US 4,106,991 and US 4,661,452 (both to Novo Nordisk A/S) and may optionally be coated by methods known in the art. Liquid enzyme preparations may, for instance, be stabilized by adding a polyol such as e.g. propylene glycol, a sugar or sugar alcohol or acetic acid, according to established met¬ hods. Other enzyme stabilizers are well known in the art. Protected enzymes may be prepared according to the method disclosed in EP 238 216. The performance of enzymes greatly depends on process condi- tions such as e.g. pH and temperature. In accomplishing the process of this invention, of course, factors such as e.g. pH-dependent performance and thermal stability should be ta¬ ken into consideration in the choice of cellulytic enzymes. Other conditions such as e.g. the addition of wetting agents, etc., also depend on the overall process to be performed, as well as the enzyme employed. The invention is further illustrated by the following non- limiting example. EXAMPLE Apparatus: The test was carried out in an Atlas LP2 Launder-O-Meter using 2 swatches per beaker. Textile: Bleached interlock knitted 100% cotton fabric, 205 g/m 2 . The fabric was cut into pieces of a size 14x12 cm (about 3.5 g each) and conditioned overnight at 20°C and 65% relative humidity under constant conditions. Enzymes: A: Reference (Cellusoft L, a commercial acid cellulase preparation produced and sold by Novo Nordisk A/S, DK- 2880 Bagsvaerd, Denmark) . B: 43 kD endoglucanase from Humicola insolens, DSM 1800. C: Variant of B (substitution D58A) D: Variant of B (substitution F132D) E: Variant of B (substitution Y280F) F: Variant of B (substitution D67R) G: Variant of B (substitution Y147S) H: Variant of B (substitution S55E) J: Variant of B (substitutions Y8F, W62E, A162P, V221S, N222S, Q223T) K: Variant of B (substitution Y147N) Experimental conditions: (Launder-O-Meter biopolishing) 4 beakers (8 swatches) were used for each test. Liquor ratio 1:20 Liquor volume 140 ml Abrasive agent 20 steel balls (d=14mm,llg) pH 5.0 Buffer 1 g/1 acetate Time 60 min Temperature 55°C Inactivation: Each test was terminated by washing all the swatches at 70°C followed by rinsing three times in a standard European home laundry machine, AEG Oko-Lavamat 665. Drying: The swatches were air dried and conditioned overnight at 20°C and 65% relative humidity. Tests: The commercial enzyme preparation A was tested in 4 dosages in the range 0-4.0 w/w%, based on the weight of the textile. Each of the enzyme preparations B-K were tested in 4 dosages in the range 0-5.0 ECU/g textile. Results: The following parameters were measured/calculated: * Weight loss, in terms of percentage, of the weight loss of the cellulase treated textile fabric and the weight loss of the textile fabric treated without cellulase (blank) . * Pilling note (PN) , measured according to SN 198525 (1990) using a Martindale Pilling Tester at 500 revolutions. The pilling note of the untreated textile as well as of the textile treated without cellulase (blank) was 1. The following table shows the measured weight loss correspon¬ ding to a resulting pilling note of 4.5 of the cellulase tre¬ ated textile. TABLE Enzyme Weight loss (Δ%) A (ref.) 5.6 B 2.0 C 1.3 D 1.3 E 2.0 F 1.7 G 1.2 H 1.0 J 1.2 K 1.5 SEQUENCE LISTING (1) GENERAL INFORMATION: (i) APPLICANT: NOVO NORDISK A/S (ii) TITLE OF INVENTION: A Method of Obtaining a Cellu¬ losic Textile Fabric with Reduced Tendency to Pilling Formation (iii) NUMBER OF SEQUENCES: 1 (iv) CORRESPONDENCE ADDRESS: (A) ADDRESSEE: NOVO NORDISK A/S, Corporate Patents (B) STREET: Novo Alle (C) CITY: Bagsvaerd (E) COUNTRY: DENMARK (F) ZIP: DK-2880 (V) COMPUTER READABLE FORM: (A) MEDIUM TYPE: Floppy disk (B) COMPUTER: IBM PC compatible (C) OPERATING SYSTEM: PC-DOS/MS-DOS (D) SOFTWARE: Patentln Release #1.0, Version #1.25 (2) INFORMATION FOR SEQ ID NO:l: (i) SEQUENCE CHARACTERISTICS: (A) LENGTH: 305 amino acids (B) TYPE: amino acid (D) TOPOLOGY: linear (ii) MOLECULE TYPE: protein (vi) ORIGINAL SOURCE: (A) ORGANISM: Humicola insolens (B) STRAIN: DSM 1800 (xi) SEQUENCE DESCRIPTION: SEQ ID NO:l: Met Arg Ser Ser Pro Leu Leu Pro Ser Ala Val Val Ala Ala Leu Pro -21 -20 -15 -10 Val Leu Ala Leu Ala Ala Asp Gly Arg Ser Thr Arg Tyr Trp Asp Cys -5 1 5 10 Cys Lys Pro Ser Cys Gly Trp Ala Lys Lys Ala Pro Val Asn Gin Pro 15 20 25 Val Phe Ser Cys Asn Ala Asn Phe Gin Arg lie Thr Asp Phe Asp Ala 30 35 40 Lys Ser Gly Cys Glu Pro Gly Gly Val Ala Tyr Ser Cys Ala Asp Gin 45 50 55 Thr Pro Trp Ala Val Asn Asp Asp Phe Ala Leu Gly Phe Ala Ala Thr 60 65 70 75 Ser lie Ala Gly Ser Asn Glu Ala Gly Trp Cys Cys Ala Cys Tyr Glu 80 85 90 Leu Thr Phe Thr Ser Gly Pro Val Ala Gly Lys Lys Met Val Val Gin 95 100 105 Ser Thr Ser Thr Gly Gly Asp Leu Gly Ser Asn His Phe Asp Leu Asn 110 115 120 lie Pro Gly Gly Gly Val Gly lie Phe Asp Gly Cys Thr Pro Gin Phe 125 130 135 Gly Gly Leu Pro Gly Gin Arg Tyr Gly Gly lie Ser Ser Arg Asn Glu 140 145 150 155 Cys Asp Arg Phe Pro Asp Ala Leu Lys Pro Gly Cys Tyr Trp Arg Phe 160 165 170 Asp Trp Phe Lys Asn Ala Asp Asn Pro Ser Phe Ser Phe Arg Gin Val 175 180 185 Gin Cys Pro Ala Glu Leu Val Ala Arg Thr Gly Cys Arg Arg Asn Asp 190 195 200 Asp Gly Asn Phe Pro Ala Val Gin lie Pro Ser Ser Ser Thr Ser Ser 205 210 215 Pro Val Asn Gin Pro Thr Ser Thr Ser Thr Thr Ser Thr Ser Thr Thr 220 225 230 235 Ser Ser Pro Pro Val Gin Pro Thr Thr Pro Ser Gly Cys Thr Ala Glu 240 245 250 Arg Trp Ala Gin Cys Gly Gly Asn Gly Trp Ser Gly Cys Thr Thr Cys 255 260 265 Val Ala Gly Ser Thr Cys Thr Lys lie Asn Asp Trp Tyr His Gin Cys 270 275 280 Leu

Claims: CLAIMS 1. A method for obtaining a cellulosic textile fabric having a strongly reduced tendency to pilling formation, the method comprising treating a cellulose-fibre-containing textile fa- brie with a cellulase (cellulolytic enzyme) capable of per¬ forming a partial hydrolysis of the fibre surface correspon¬ ding to a weight loss of less than 2 w/w% based on the untre¬ ated cellulosic textile fabric. 2. A method according to claim 1, wherein the pilling forma- tion corresponds to a pilling note of at least 4, more pre¬ ferably of at least 4.5. 3. A method according to claim 1 or 2, wherein the textile fabric contains cellulose fibres selected from the group con¬ sisting of cotton, viscose (rayon) , lyocell; all blends of viscose, cotton or lyocell with other fibers such as polye¬ ster; viscose/cotton blends, lyocell/cotton blends, viscose/- wool blends, lyocell/wool blends, cotton/wool blends; flax (linen) , ramie and other fabrics based on cellulose fibers, including all blends of cellulosic fibers with other fibers such as wool, polyamide, acrylic and polyester fibers, e.g. viscose/cotton/polyester blends, wool/cotton/polyester blends, and flax/cotton blends. 4. A method according to any of the claims 1-3, wherein the cellulase is a monocomponent cellulase, preferably an endog- lucanase (EC 3.2.1.4). 5. A method according to claim 3 or 4, wherein the cellulase is a icrobial cellulase, preferably a bacterial or fungal cellulase, more preferably a fungal cellulase. 6. The method according to claim 5, wherein the cellulase is an acid cellulase, preferably a fungal acid cellulase, more preferably a fungal acid cellulase with substantial cellulo¬ lytic activity at acidic conditions which is derived from or producible by fungi from the group of genera consisting of Trichoderma, Actinomyces, Trichoderma, Myrothecium, Aspergil¬ lus, and Botrytis . 7. The method according to claim 6, wherein the cellulase is derived from or producible by fungi from the group of species consisting of Trichoderma viride , Trichoderma longibrachia- tum , Myrothecium verrucaria , Aspergillus niger, Aspergillus oryzae, and Botrytis cinerea . 8. The method according to claim 5, wherein the cellulase is a neutral or alkaline cellulase, preferably a fungal neutral or alkaline cellulase, more preferably a fungal alkaline cel¬ lulase with substantial cellulolytic activity at alkaline conditions which is derived from or producible by fungi from the group of genera consisting of Aspergillus, Penicillium, Myceliophthora, Humicola, Irpex, Fusarium, Stachybotrys , Sco- pulariopsis, Chaetomium, Mycogone, Verticillium, Myrothecium, Papulospora, Gliocladium, Cephalosporium and Acre-T-oniuj-i. 9. The method according to claim 8, wherein the alkaline cel¬ lulase is derived from or producible by fungi from the group of species consisting of Humicola insolens , Fusarium oxyspo- rum, Myceliopthora thermophila, or Cephalosporium sp. 10. The method according to claim 9, wherein the cellulase is derived from or producible by fungi from the group of species consisting of Humicola insolens , DSM 1800, Fusarium oxyspo¬ rum, DSM 2672, Myceliopthora thermophila, CBS 117.65, or Cephalosporium sp . , RYM-202. 11. The method according to any of the claims 8-10, wherein the treatment is carried out at a pH below about 9, pre- ferably at a pH below 6, more preferably at a pH of from about 4.5 to about 5.5, especially at a pH of about 5.0. 12. The method according to claim 10 or 11, wherein the cel¬ lulase is a 43 kD endoglucanase derived from or producible by Humicola insolens , DSM 1800, SEQ ID NO:l, or a functional analogue of said cellulase which i) comprises an amino acid sequence being at least 60% homo¬ logous with the amino acid sequence of the cellulase, ii) reacts with an antibody raised against the cellulase, and/or iii) is encoded by a DNA sequence which hybridizes with the same probe as a DNA sequence encoding the cellulase. 13. The method according to claim 12, wherein the cellulase is a variant of the 43 kD endoglucanase derived from or pro- ducible by Humicola insolens , DSM 1800, SEQ ID NO:l, modified by substitution of one or more amino acid residues in one or more of the positions 8, 55, 58, 62, 67, 132, 147, 162, 221, 222, 223, 280; or modified by truncation, preferably geneti¬ cally truncation, at any position from position 213. 14. The method according to claim 12, wherein one or more the amino acid residues are substituted as follows Y8F S55E/D 5 D58A/S/N W62E D67R/N F132A/D/E/G Y147S 10 A162P V221S N222S Q223T Y280F. 1515. The method according to claim 5, wherein the bacterial cellulase is derived from or producible by bacteria from the group of genera consisting of Pseudomonas or Bacillus lautus . 16. The method according to any of the preceding claims, wherein the treatment is carried out in any wet processing 20 stage of a conventional textile fabric manufacturing process. 17. The method according to claim 16, wherein the treatment is accomplished in high-speed circular systems such as jet- overflow dyeing machines (jet-dyer) , high-speed winches and jiggers 2518. The method according to claim 16, wherein the treatment is accomplished in a J-Box, on a Pad-Roll or in a Pad-Bath during a two-step biopolishing process.

Inventors: LUND HENRIK, PEDERSEN HANNE HOEST, LUND, HENRIK, PEDERSEN, HANNE, HOEST
Applicants: LUND HENRIK, NOVONORDISK AS, PEDERSEN HANNE HOEST, LUND, HENRIK, NOVO NORDISK A/S, PEDERSEN, HANNE, HOEST
Application year: 1995
Main classification: D06M16
IPC codes: C12N9, C12N15, C12R1, C12S3, C12S11, D06M16