Method for enzymatic treatment of textiles such as wool

Abstract

The application provides a method of treating fibrous textile goods comprising treating the fibrous textile goods with an enzyme. This enzyme can be used to covalently link one or more active functional compounds to the fibres and/or to trap one or more acitve functional compound within an inter-fibre matrix and/or within an intra-fibre matrix formed by the action of the enzyme. Preferably, the enzyme is a traglutaminase, especially a calcium-dependent transglutaminase. The enzyme may be used to add primary-amine containing active agents to the textile goods and also for the addition of proteins or peptides that have functional groups linked to them.

Description

FIELD OF THE INVENTION

[0001] The present invention relates to a method of treating fibrous textile goods, such as wool, wool fibres or animal hair with an enzyme, such as a transglutaminase, preferably either including or in the absence of a protease enzyme. This treatment can be used to trap one or more active functional compounds within, by linking either covalently or non-covently such compounds onto, the fibrous textile goods.

BACKGROUND TO THE INVENTION

[0002] The use of enzymes in the treatment of textile goods has gained widespread acceptance and the applications of such technology are many and diverse, including industrial processes and household laundering. Thus, enzymes find industrial applicability in the desizing of fabric, in enzymatic stone-washing of denim to create an aged look, and in numerous other treatments to impart enhanced fabric properties, such as a clean fabric surface, free of microhairs and fibres, or improved pilling properties or fabric hand. In domestic laundry products, enzymes are employed to assist in the cleaning of goods, to remove soils and stains and also to counter the formation of surface fibre, which gives a worn appearance.

[0003] In particular, proteases have been widely employed in the industrial treatment of wool goods to impart desirable properties. There exists a general understanding of the mode of action of protease on wool substrates. The enzymatic processes that are currently being used, however, are difficult to control and can lead to results that are not sufficiently predictable and reproducible and cause significant damage to the fibre cuticle with consequent strength loss. The major problems associated with wool goods are its tendency to shrink and its handle (prickliness).

[0004] The dimensional stability of textile articles is obviously of great significance, influencing the acceptability to the consumer by defining the fit and comfort after repeated launderings. A variety of methods to produce shrinkproof wool materials are known and widely used. The most common method is a chlorine-based process, which comprises an acid chlorination of the wool material followed by a polymer application. Alternative methods involve coating of the wool fibres to reduce the friction coefficient using a polymer or monomers, which are polymerised on the fibres. These methods achieve a significant level of shrink-resistance to wool textiles, but they are difficult to control, and may affect adversely the handle of wool goods, as well as generate damaging substances that may be released into the environment. Therefore, environmentally friendly methods such as enzyme based processes and less aggressive chemical processes, such as the low temperature plasma treatment have been suggested.

[0005] The scalar structure of the wool fibre is partly responsible for the tendency of wool goods to dimensional instability. One idea to reduce wool shrinkage is to remove or alter the scales of the wool fibre surface using, for example, proteases. Ideally, a commercial process would remove the surface scales to a limited extent, reducing the fibre coefficient of friction without significantly reducing wool fibre strength. The use of proteases alone is not yet widely used industrially, the main reasons being the significant losses of weight and strength that result and also the relatively low degree of reproducibility. Many methods based on the degradation of the structure of scales are destructive, causing molecular degradation of the proteins, which is ultimately responsible for the macroscopic reduction in weight and strength of the processed wool or animal hair textiles.

[0006] Enzymatic treatments have also been suggested to improve the handle of wool textiles as an alternative to the use of various chemical agents, such as silicone softeners. Protease treatments may however, if not closely controlled, cause undesirable levels of weight and strength loss on the wool textiles.

[0007] Protease treatments of wool goods invariably lead to a reduction, however slight, in fabric properties such as tensile or bursting strength. There is also a measurable weight loss arising from enzyme treatments. Such reductions must be balanced against the enhancement of properties such as pilling performance or fabric hand, and processing conditions and enzyme type are carefully selected to maximise the desirable benefits whilst controlling losses in strength and weight.

[0008] Transglutaminase is an enzyme which is found in a number of organisms and different organs and tissues. It is responsible for cross-linking proteins by forming covalent bonds between lysine and glutamine residues. Transglutaminases usually have a higher affinity for glutamine residues than lysine residues.

[0009] A variety of amines have been reported as substrates for transglutaminase, including dansylcadaverine, methyl amine, butyl amine, bistamine and putrescine and hydroxylamine. Hydroxylamine is in fact the amine donor in a standard assay for transglutaminase activity wherein hydroxylamine is covalently bound to an N-terminal blocked peptide containing glutamine and glycine to produce hydroxamate, which is detected by colour formation in the presence of ferric chloride and acid. One Unit of transglutaminase is defined as that amount which will form 1 &mgr;M of hydroxamate per minute at 37° C.

[0010] Transglutaminases may be used in combination with proteases to optimise an enzyme system that minimises the effect of such less desirable effects like a reduction in weight and strength, whilst achieving various desirable finishing effects, such as shrink-resistance.

[0011] Some of the reductions in weight and strength are a consequence of the mechanical agitation during processing, but the protease treatments alone do contribute significantly to reductions in weight and strength. Enzyme processing can be carried out in a variety of machinery types, which are commonly available in the industry. The characteristics of these machines are varied in terms of capacity, mechanical action and agitation and liquor-to-goods ratio, etc.

[0012] Prior to an enzymatic treatment, the fabric to be treated preferably should be clean and free of any impurities, such as oils and Does or softening agents, which may interfere with the action of the enzyme. Fabrics are preferably scoured prior to the enzyme treatment. It is of benefit, therefore to optimise both all process parameters and enzyme system in order to minimise these losses and to improve the quality of the finished textile goods.

[0013] A variety of enzyme-based methods have been used to process wool textiles. U.S. Pat. No. 5,529,928 describes a method using an initial oxidative step or an enzyme treatment (e.g. a peroxidase, a catalase, or a lipase) followed by a protease treatment, followed by heat treatment to obtain wool textiles with improved handle and shrink-resistant properties.

[0014] Lorand et at. (1979) observed the specificity of the guinea pig liver transglutaminase for synthetic primary amines. It is revealed in this study that optimal transglutaminase activity is achieved when compounds have alkyl amine side-chain lengths equivalent to 5 methylene groups, no branching nor groups bulkier than methylene along the alkyl amine chain and hydrophobic moieties attached to the alkyl chain.

[0015] U.S. Pat. No. 5,490,980 describe a method using transglutaminases to cross-ink beneficial substances containing an amine moiety to glutamine residues in skin, hair or nails, but not to fibrous textile goods.

[0016] While wool fibre (in the form of tops, yarns or fabrics) is dead, human hair is still growing and has a living root. As a consequence, the type of active agents that can be applied to living hair in a scalp are different from those applicable to wool fibres, which can be treated in industrial conditions. Treatment temperature, pH, type and harshness of chemicals are very different. In particular, the active agents applicable to wool and hair are generally different, and the process of applying transglutaminase and any active agent are also generally different (for example, by using microbial transglutaminase, which has an optimum temperature of 50° C.).

[0017] Both human hair and wool consist mainly of keratins and have approximately the same basic morphology. Human hair is, however, more resistant to chemical and enzymatic attack than wool.

[0018] Wool fibres are available in large quantities and are more flexible than hair and are therefore easy to spin into threads and make garments. Because of the protruding scales in the wool fibre felting shrinkage is a major problem, mainly in knitted garments.

[0019] Differences also exist in the type of chemicals that may be applied. Strong alkali and acids, dyes, resins, etc, can easily be applied to wool without concern to toxicity to the wool, since it is dead. The range of finishing compounds applicable to human hair and wool are also different. Wool processing takes place in large industrial machinery and allows for the use of harsh chemicals and harsh treatment conditions.

[0020] Japanese patent JP 3213574 describes a process to treat wool or animal hair using a calcium independent transglutaminase of mircrobial origin by cross-linking the amino acid functional groups of the cuticle of animal hair so as to produce hair or hair fibre containing material having improved shrink-resistance, pilling resistance and hydrophobic property.

[0021] The deficiencies in terms of performance, cost and environment of the wool processing methods used currently in the textile industry indicate that there is a need for a new process that imparts improvements in shrink resistance, softness, appearance, resistance to pilling without a decrease in tensile and bursting strength.

[0022] This invention features a number of departures from normal accepted practice in the enzymatic treatment of wool goods, which renders it novel both in terms of application method and in the effects achieved.

[0023] The invention provides a method of treating fibrous textile goods, preferably derived from wool or animal hair, comprising treating the fibrous textile goods with an enzyme to either covalently or non-covalently bind one or more active functional compounds to the fibres and/or to trap one or more functional compounds within an inter-fibre matrix and/or within an intra-fibre matrix formed by the enzyme.

[0024] A second aspect of the invention provides a method of protecting fibrous textile goods, preferably derived from wool or animal hair, from attack by biological detergents comprising treating the fibrous textile goods with an enzyme to covalently link one or more fibres of the fibrous textile goods.

[0025] A third aspect of the invention provides a method of treating fibrous textile goods to improve dimensional stability and/or improve yarn strength comprising treating the fibrous textile goods with a calcium-dependent transglutaminase. Such a treatment also may improve tensile and burst strength, shrinkage resistance, handle, reduces pilling, improves softness, improves dye uptake and washfastness, especially when used together with a protease.

[0026] Preferably, the fibrous textile goods are derived from wool fibre blended with one or more cellulosic or synthetic fibres.

[0027] Preferably, the enzyme is a transglutaminase (TGase), especially a calcium-dependent transglutaminase such as tissue type II transglutaminase.

[0028] The biological detergent may be one containing a protease. The inventors have unexpectedly found that using an enzyme to cross-link the fibres reduces the amount of damage from biological detergents such as those containing proteases, and effectively reduces the amount of dye released during washing.

[0029] Fibrous textile goods obtainable by the methods of the invention are also provided.

[0030] In the context of the present invention a pretreatment with reducing agents may be applied with the intent of breaking cystine bonds on wool to make it more accessible to further action by enzymes.

[0031] Alternatively, an oxidative treatment may be used.

[0032] Proteolytic enzymes may be used to break down the cuticle structure in the fibre surface in such a way to render it more accessible to transglutaminases, without excessive fibre damage and loss of weight and strength. Transglutaminases form intra- and inter-isopeptide bonds in the keratin molecule, stabilising the protein molecules. Their use results in an increase in total fibre and fabric strength, as well as rendering the fabrics less prone to felt. When used in combination with proteases, transglutaminases prevent excessive molecular breakdown associated with protease treatments, preventing thereby a reduction in weight and strength loss.

[0033] The proteases may be used before, during or after the use of transglutaminase.

[0034] The processing of wool textiles with transglutaminases may involve a treatment with calcium-dependent transglutaminases such as tissue transglutaminase, alone or after a pretreatment with a protease. Incubation with transglutaminases carried out prior to a protease treatment leads to a reduction in the loss of yarn and fabric strength compared to a protease treatment only (under the same conditions). The same benefits may also result from processing by pre-soaking the wool or animal hair fibres with TGases in the absence of Ca2+to allow a better penetration of the enzyme into the fibre. The enzyme may then be activated in a later stage by the addition of the Ca2+ions.

[0035] The use of a calcium dependent transglutaminase to deliver benefits such as increased tensile and burst strength, improved shrink resistance, handle, reduction of pilling, improved softness, improved softness and improved dye uptake and washfastness presents the advantage of an effective control of the enzyme activation/deactivation by the addition of either calcium or a sequestering agent.

[0036] The selection of an optimised transglutaminases, specifically tailored by gene manipulation, could ensure a high degree of dimensional stability, whilst minimising the negative effects from other enzymes (proteases) or chemicals, such as strength loss and harsh handle. Further, the enzyme preparation may be tailored to deliver improvements in other areas as well as dimensional stability.

[0037] Such a recombinant enzyme may be identified or produced by conventional recombinant technology. EP 0268772A2 describes the expression of biologically active Factor XIII. U.S. Pat. No. 6,190,896 describes the production of an active human cellular transglutaminase, and WO 0129187 describes a process for the production of a microorganism-origin transglutaminase.

[0038] Transglutaminase or its optimised derivatives can be used to improve, for example, fabric handle, pilling performance, wrinkle resistance, the setting process, improve durable press finishing.

[0039] The active agents may be attached to the fibrous textile goods by means of using a transglutaminase to react a primary amine group with a peptide bound &ggr;-glutamine or a &ggr;-glutamine with &egr;-lysine residue on the fibres and form a covalent bond. Alternatively, the active agents may be trapped within a matrix of inter-cross-linked fibres or, indeed, within an intra-fibre cross-linked matrix. That is, within a matrix by cross-inking adjacent fibres or by cross-linking within the same fibre.

[0040] The active agents may be modified by addition of a primary amine to the active agent. Preferably, the active agent comprises the group —R′NH2 where —R′ is an aliphatic branched or unbranched hydrocarbon chain containing 1 to 8, preferably 2 to 6, more preferably at least 5 carbon atoms. Preferably the R′ is unbranched.

[0041] Alternatively, the primary amine of general formula of —R′NH2 may be linked to a different functional group which imparts further functionalities to the fibrous goods. These may, in turn, be used to link further active agents, such as commercial polymers for improving shrink and improving softness, to the fibrous goods.

[0042] The active agent may have several alkylamine moieties. These may be used to cross-link fibres or to bond the fibres to further active agents.

[0043] Putrescine (1,4-diaminobutane) may be used as the active agent.

[0044] Transglutaminase or its optimised derivatives can also be used to incorporate either covalently or non-covalently active agents that, once attached into the fibre surface, improve the binding and consequently the performance of active agents (e.g. commercial polymers used for shrink resistance—such as silicone oils and cationic polymers—and improving softness—such as amino silicones).

[0045] Suitable active compounds include but are not limited to perfumes, insect repellents, dyeing agents, softening agents, water repellents, antimicrobial agents, sunscreens and mixtures thereof. The active agents include but are not limited to intact proteins, hydrolysed proteins and modified hydrolysates, such as peptides and peptide derivatives, keratin, silk, casein, fibronectin and hydrolysed collagen.

[0046] Preferred fragrances include vanillin, thymol and menthylsalicylate.

[0047] Preferred antimicrobials include phenol, cresol, hydroxybenzoates, triclosan and cinnamic acid.

[0048] The active compounds may, in a first step, be linked to a protein or a protein fragment chemically, and in a second step, the protein or a protein fragment containing the active agent is crosslinked to the fibres using transglutaminase. The protein or protein fragment may be casein, for example. The compound may be a shrinkage prevention compound.

[0049] TGase cross-linking of polyamines to wool also provides additional amine groups that may be used as a platform to link other compounds (using e.g. carbodimides—B. F. Erlanger, 1980, Preparation of Antigenic Hapten—Carrier Conjugates, Methods in Enzymology, 70, 85-104). The ability of TGase to give wool specific and desired functions using these methods presents considerable advantages.

[0050] All compounds that produce a beneficial finishing effect on wool or animal hair textiles can also be used in the present invention given that the compound can be modified to contain at least one primary amine.

[0051] The proteolytic enzyme to be used in the context of the present invention may be from plant, animal, bacterial or fungal origin. The proteases used are most preferably subtilisins, such as Savinase 16L (ex. Novo Nordisk).

[0052] Examples of the transglutaminase types suited for this application include the following: guinea pig liver, human origin, maize, alfalfa (Medicago saliva), slime mould (Physarum polycephalum), Phytophtora cactorum and bacteria (Bacillus subtilus, Streptoverticillium mobaraense). Ajinomoto Inc. patented a method for production of a commercial transglutaminase by a batch fermentation process using bacteria containing genes from Streptoverticillium sp. Preferably a Ca2+activated tissue transglutaminase should be used. This list is not intended to be exhaustive, and omission from this list should not be taken as an indication that particular types are more suited that others. Indeed, the ideal transglutaminase preparation may be derived from genetic manipulation of one of any number of naturally occurring sources. Further suitable transglutaminases may be derived from mammals, insects, crustaceans, plants and microorganisms.

[0053] As stated above, it has been found that a significant degree of dimensional control of wool and wool blend fabrics may be achieved if a transglutaminase is used. The transglutaminase enzyme used for such a treatment may be chosen from mammalian, plant or microbial source, but to optimise the properties of the treated fabric, it may be advantageous to employ an enzyme system specifically manufactured to achieve good dimensional stability and whose activity is easily controllable.

[0054] Among the existing transglutaminases, a calcium dependent transglutaminase, such as tissue (type II) transglutaminase, presents several advantages. This enzyme is activated by the presence of calcium ions, which renders it easily controllable. It is active at room temperatures, being most active at 37° C., which allows a wide range of processing methods to be used, as well as significant energy savings to be made. It is also readily inactivated by heating to 60° C. or by removal of Ca2+either by washing or with addition of chelating agents for divalent metal ions, e.g. EDTA.

[0055] It is known that enzymes require specific and controlled treatment conditions in order to achieve optimum and reproducible end-effects during processing of wool goods. Typically, the type of electrolyte used, temperature, liquor pH and agitation are all controlled to a high degree to ensure an effective and even treatment over the goods as a whole.

[0056] The treatment liquor may contain suitable pH-buffering agents to maintain a constant pH in the range appropriate for optimum activity of the enzyme being employed. In the case of transglutaminases, the solution may also contain a suitable reducing agent and an appropriate concentration of calcium ions if the mammalian transglutaminase is to be used. Other auxiliaries may be present in the treatment liquor—for example surfactants, provided that their presence does not interfere with the action of the enzyme. In this regard, the co-application of the enzyme treatment with other finishes from die same liquor is not to be excluded, provided that the enzyme treatment and any other co-applied treatment(s) are mutually compatible.

[0057] The impregnation of the wool goods with transglutaminase may be carried out at a temperature of 15-70° C., especially 15-60° C., most preferably 30-40° C. The enzymes may be dissolved in water at concentrations between 0.5-10.0 &mgr;m of enzyme per ml of treatment liquor, most preferably 1.0-5.0 &mgr;g of enzyme per ml of liquor. The incubation time should be from at least 30 minutes up to 18 hours, depending on the enzyme concentration and treatment temperature.

[0058] If a proteolytic enzyme is to be used, it is most preferably applied at temperatures between 45-55° C. during 15 to 60 minutes. The process can, however, be carried out at lower temperatures for a longer treatment time.

[0059] Enzyme processing can be carried out in a variety of machinery types, which are commonly available in the industry.

[0060] Fabrics derived from wool fibres are suited to this process. Further, fabrics constructed from wool/synthetic blends or wool/cellulosic fibre blends (such as cotton/wool) are also suitable for treatment by this process.

[0061] In the present invention the textile samples may be submitted, for example, to a pretreatment with a reducing agent prior to the application of transglutaminase. Textile samples may also be pretreated with a proteolytic enzyme before applying the transglutaminase enzyme.

[0062] For example, the guinea pig liver transglutaminase (a tissue transglutaminase, which is commercially available from Sigma) may be applied to a wool yarn by immersion in a solution containing the enzyme. The reaction may be carried out in a media with or without a reducing agent, such as dithiothreitol, 2-mercaptoethanol, and glutathione.

[0063] This enzyme may be activated by the presence of calcium ions, and is most active at 37° C., and it is readily inactivated by washing with chelating agents or heating to 60° C.

[0064] Other transglutaminases may be used, the treatment parameters depending on which specific enzyme is to be applied. For example, microbial transglutaminase obtainable from Ajinomoto Inc. may be used.

[0065] The invention will now be further illustrated by reference to a series of examples but the invention is not limited thereto. In the examples, TGase refers to tissue transglutaminase from guinea pig liver. The use of microbial transglutaminase is denoted by mTGase obtained from Streptoverticillum by Ajinomoto Inc.

[0066] FIG. 1a shows that yarn strength change (from control) of samples treated with TGase/Ca for several treatment times (control treated in Tris-HCI buffer without TGase (-▪-)). One set of samples was pretreated with Savinase 16L (-□-) and a second set in buffer alone with no Savinase added (Savinase control).

[0067] FIG. 1b shows yarn elongation change (from control) of samples treated with TGase/Ca for several treatment times (control treated in Tris-HCI buffer without TGase). One set of samples was pretreated with Savinase 16 L (-□-) and a second set in buffer alone with no Savinase added (Savinase control (-▪-)).

[0068] FIG. 2 shows yarn strength change from control of samples treated during 6 hours with a range of concentrations of TGase (-570 -) (controls -♦- were treated in the same manner except without adding TGase). The samples were pre-treated with Savinase 16 L and buffer only control.

[0069] FIG. 3a shows yarn strength change from control of samples treated with TGase/Ca2+during 18 hours (controls were treated in the same manner except without adding TGase). The samples were pre-treated with sodium carbonate (Carb) and sodium sulphite (Sul). The samples were also treated with Savinase 16 L (Sav) with respective buffer only controls (Ct).

[0070] FIG. 3b shows percentage strength gain from control versus percentage elongation gain from control of yarn samples treated with 1.0 and 5.0 &mgr;g/ml of TGase (corresponding to 1 and 5 in the graphite) for samples pretreated with sulphite, chlorine and PMS (controls were treated in the same manner except without adding TGase).

[0071] FIG. 3c shows percentage strength gain from control versus percentage elongation gain from control of yarn samples treated with 10.0, 100.0 and 1000.0 &mgr;g/ml of mTGase (corresponding to 10, 100 and 1000 in thc graphic) for samples pretreated with sulphite, chlorine and PMS (controls were treated in the same manner except without adding TGase).

[0072] FIG. 4 shows yarn strength loss caused by a protease treatment (change from control samples). Samples were treated with Savinase prior (SavCtTG and SavTG—red) and after (CtTGSav and TGSav—blue) an 18-hour tTG treatment (control—Ct, Sav—Sav). Savinase controls were treated in the same manner except without Savinase 16 L and tTG controls without tTG),

[0073] FIG. 5a shows absorption at 511 nm of the washing liquor after each cycle of detergent washes of samples submitted to different TGase treatments after several washes with a biodetergent (the percentage reduction in absorbance relative to the control is shown as percentage values). Cycles of detergent wash followed by a transglutaminase treatment were repeated 3 times (tTG5—tTG at 5.0 &mgr;/ml; tTG5 tryptone—tTG at 5.0 &mgr;g/ml, with 1.0 mg/ml of tryptone (casein digest); mTG100—mTG100 at 100.0 &mgr;g/ml.). Controls were treated in buffer without adding TGase.

[0074] FIG. 5b shows tensile strength of yarns unraveled from fabrics submitted to different TGase treatments for cycles 1 and 3 (the percentage strength gain relative to the control is shown as percentage values). The yarn strength of the control samples is 2.19 N (black line).

[0075] FIG. 6 shows a table indicating felting shrinkage after three 5A washes of samples treated with transglutaminase and an active agent followed by a treatment with a commercial polymer.

[0076] FIG. 7 shows softness of wool samples after a treatment with tissue and microbial transglutaminase and an active agent followed by a treatment with a commercial softener.

[0077] FIG. 8 shows subjective analysis of residual scent after a treatment with 5.0 and 20.0 &mgr;g of tTGase per ml. of liquor and an added scent by a panel of 12 judges (2 and 5 days after treatment). The panel graded the samples from the least to the most intense residual scent. A control was treated in the same manner but without tTGase.

[0078] FIG. 9a shows wool fibres treated with transglutaminase in the presence of calcium ions and flourescine cadaverine.

[0079] FIG. 9b shows wool fibres treated with transglutaminase in the presence of EDTA and flourescine cadaverine.

EXAMPLE 1

Transglutaminase Cross-Linking of Wool for Different Treatment Times

[0080] Samples of 100% superfine lambswool yarn {fraction (1/13)}nm (ex. Patons) were washed in a solution containing a reducing agent, 5.0 g/l of sodium sulphite, and 1 g/l of a non-ionic detergent at a liquor to fibre ratio of 250 ml/g for 30 minutes at 60° C., and subsequently rinsed in water. The yarn samples were then treated in a shaker rotating at 100 rpm for 60 minutes at 37° C., in a 0.05 M TRIS buffer solution (the pH was adjusted to 8.5 with hydrochloric acid) containing 1% of Savinase 16 L (ex. Novo Nordisk) on the weight of wool yarn. The treated samples were washed with a non-ionic detergent at pH 5, and then in boiling water for 15 minutes to deactivate the proteolytic enzyme. Finally, the samples were rinsed before submitted to further treatment. As a control to the protease treatment, sulphite washed yarn samples were also treated with buffer only. The guinea pig liver transglutaminase (ex. Sigma) was then applied to the Savinase treated and respective buffer control samples at 1.0 &mgr;g of transglutaminase per ml of liquor in a buffered solution with 0.05 M TRIS buffer (the pH was adjusted to 8.5 with hydrochloric acid). The liquor also contained 5 mM dithiothreitol (DTT) and 5 mM of calcium ion. The liquor to yarn ratio applied was 1:12. The yarn samples were then incubated in a shaker rotating at 100 rpm for a period of time between 2 to 18 hours 8 hours at approximately 37° C. As a control to the transglutaminase treatments yarn samples were treated under exactly the same parameters in a solution containing buffer, 5 mM DTT and 5 mM calcium ion.

[0081] The enzymatic reaction was stopped after the specified time and the yarn samples were washed in a buffered phosphate saline solution (PBS) pH 7.4 and 1.0% of Tween 80 detergent. The yarn samples were washed in three consecutive cycles with this solution. The yarn samples were then rinsed in water in three consecutive cycles and then dried and conditioned at the standard temperature and humidity.

[0082] The tensile strength or breaking load of the yarn samples and elongation at break were determined by the method BS EN ISO 2062:1995, and the transglutaminase treatments were compared to a buffer alone treated control (no TGase added) for both the Savinase treated samples and the Savinase controls (no Savinase added).

[0083] The greater improvements in strength were obtained with transglutaminase treatments following a protease treatment (see FIG. 1a). There was also a significant increase in elongation at break for die transglutaminase treated samples, in particular for those submitted to a Savinase pretreatment (see FIG. 1b).

EXAMPLE 2

Transglutaminase Crosslinking of Wool—Optimisation of Delivery and Concentration of Enzyme Used

[0084] Samples of 100% wool yarn previously treated with sodium sulphite (as described in Example 1) were treated with Savinase 16L in exactly the same manner as described above. All samples were treated with 5.0, 20.0 and 100.0 &mgr;g of guinea pig liver transglutaminase per ml of liquor, and incubated for 6 hours at 37° C. All other treatment parameters were the same as in Example 1. To a second set of samples pretreated exactly in the same manner ⅓of the total transglutaminase was added to the treatment bath every two hours (all other treatment parameters were the same). The samples were washed and dried as described in Example 1.

[0085] There was a significant improvement in the strength of all transglutaminase treated yarns compared to the buffer treated controls. These improvements were significantly greater for yarn pretreated with Savinase. In particular, the treatment with 5.0 &mgr;g of transglutaminase per mL of liquor produced a gain of strength of about 34% compared to the respective control, while the Savinase control samples treated with transglutaminase resulted in a gain of 15% (see FIG. 2). Adding enzyme in three separated aliquots on the same incubation time gave a significant improvement in strength gain compared with the samples treated with one batch of enzyme at the start of the process.

EXAMPLE 3

Effect of Different Pretreatments on the Transglutaminase Crosslinking of Wool

[0086] Pretreatment with sodium sulphite and sodium carbonate

[0087] In this example two batches of yarn samples were first treated with a) 0.5 g/L of sodium carbonate and 1 g/l of a non-ionic detergent and b) 5.0 g/l of sodium sulphite and 1 g/L of a non-ionic detergent both at a liquor to fibre ratio of 250 ml/g for 30 minutes at 60° C. Samples from a) and b) were then submitted to a Savinase treatment as described in Example 1. The proteolytic reaction was stopped by washing the samples with a non-ionic detergent at pH 5 and then in hot water at 80° C. for 15 minutes. Finally, the samples were rinsed before submitted to further treatment. As a control to the protease treatment, yarn samples from a) and b) were also treated with buffer only.

[0088] The four resulting sets of yarn samples were then treated with 1.0 &mgr;g of transglutaminase per ml of liquor, and incubated for a period of time between 2 to 18 hours at ambient temperature. All other treatment parameters were the same as in Example 1. As a control to the transglutaminase treatments yarn samples were treated as in Example 1.

[0089] The results indicate that the transglutaminase treatment for the samples pre-treated with a reducing agent such as sodium sulphite result in a greater increase in yarn strength than those treated with sodium carbonate (for both Savinase treatment and respective buffer control—FIG. 3). In particular, the sulphite treatment followed by Savinase and finally by transglutaminase results in an increase in strength of 37%.

[0090] Pretreatment with chlorine and permonosulphuric acid (PMS)

[0091] In this example samples of 100% wool yarn samples treated with sodium sulphite (as described in Example 1) and 100% wool knitted fabric samples (supplied by Cooper & Roe, UK) pretreated with chlorine and permonosulphuric acid (PMS) were compared in terms of type of pretreatment on transglutaminase cross-linking. All samples were pretreated with Savinase 16 L in exactly the same manner as described in Example 1. Samples from each type of pretreatment were treated with 1.0 and 5.0 &mgr;g of guinea pig liver transglutaminase per ml of liquor. All other treatment parameters were the same as in Example 1.

[0092] A second set of samples was treated with microbial transglutaminase from Ajinomoto Inc. Samples from each type of pretreatment were treated with 10.0, 100.0 and 1000.0 &mgr;g of microbial transglutaminase per ml of liquor. The treatments were carried out in a TRIS-HCl buffered solution pH 7.0 at 50° C. for 2 hours. The liquor also contained 5 mM DTT. The liquor to yarn ratio applied was 1:12.

[0093] The chlorine and PMS treated samples were compared with samples treated with sodium sulphite and sodium carbonate incubated (as described above) with 5 &mgr;g of guinea pig liver transglutaminase per ml of liquor and 100 □g of microbial transglutaminase per ml of liquor. Tensile strength and elongation at break were determined for all samples (FIGS. 3b and 3c) and all transglutaminase treatments were compared to buffer only treated controls.

[0094] It can be seen from FIGS. 3a and 3b that the effect of a transglutaminase treatment varies for the three types of pretreatment. The gain in strength is greater for PMS treated fabric and the percentage elongation gain is greater for the sulphite treated yarns, for both tissue and microbial transglutaminases. Strength gains as high as 30% comparing to the control can be achieved for PMS treated fabrics, and elongation gain of up to 35% comparing to the control were obtained for the sulphite pretreatment using the microbial TG.

EXAMPLE 4

Transglutaminase Treatments Prior to Protease Treatment

[0095] This experiment was carded using the same procedure as described in Example 1, except that in one batch of samples the protease treatment was carried out prior to the transglutaminase treatment and on the second batch the protease treatment was carried out after the transglutaminase treatment. In both yarn sample batches the concentration of Savinase 16 L were carried out as described in Example 1. All samples were treated with 1.0 &mgr;g transglutaminase was per ml of liquor, and incubated for 18 hours at 37° C. All other treatment parameters were the same as described in Example 1. The samples were washed and dried as described in Example 1.

[0096] The results (see FIG. 4) indicate that the transglutaminase treatment prior to the Savinase treatment not only reduced the loss of strength caused by the subsequent protease treatment (comparing to the Savinase/protease treatment) but also increased the strength of the yarns in a greater extent comparing to the transglutaminase buffer control (comparing to die Savinase/protease treatment).

EXAMPLE 5

Protection of Wool Fibres and Garments from Attack with Domestic Biodetergents Using Transglutaminase

[0097] In this example 10 g samples from a 100% wool knitted fabric (dyed with a reactive red dye) were washed with 10 ml/l of Persil Performance (commercial biodetergent containing proteases) for 30 minutes at 40° C. with a LR of 1:15 in 250 ml beakers in a shaker at 100 rpm and then flat dried.

[0098] One set of the washed samples was then treated with 5.0 and 20.0 &mgr;g/mL of tTGase, 5.0 &mgr;g/mL of tTGase and 1.0 mg/mL of a casein enzymatic digest (tryptone) for 2 hours at 37° C., pH 8.5 (compared with a control treated only with buffer under the same conditions). Another set of samples was incubated with 100 &mgr;g/mL of mTGase at 55° C., pH 7.0 for 1 hour (compared to a buffer only control treated under the same conditions). Samples were then washed again as described above and treated with transglutaminase and the procedure repeated three times.

[0099] The absorbance of the washing solutions was used as a measure of the amount of dye released into the washing bath after each washing cycle (FIG. 5a). The percentage values shown in FIG. 5a illustrate the reduction in absorbance at 511 nm, which was calculated as the percentage difference in the measured absorbance between control samples treated only with buffer and the transglutaminase treated samples. After 3 detergent wash/transglutaminase treatment cycles the treated fabrics still release significantly less dye than the control treated only with buffer.

[0100] Strength loss and elongation was also measured, both after the transglutaminase treatment and after each detergent wash. The results in FIG. 5b show an increasing retention of strength of the transglutaminase treated samples after each detergent wash (compared to samples treated with buffer alone).

EXAMPLE 6

Effect of Transglutaminase Mediated Incorporation of Active Compounds into Wool Fibres on Felting Shrinkage

[0101] In this example samples of a 100% wool knitted fabric (supplied by Cooper & Roe, UK) were treated with Savinase 16 L using the same procedure as described in Example 1. A pancreatic digest of milk casein (Tryptone) and putrescine were incorporated into wool fibres using transglutaminase. Commercial polymers used for wool shrinkage prevention (supplied by Precision Processes Textiles, UK) were added to fabric samples treated only with Savinase 16 L and to fabrics treated with transglutaminase and an active agent (polymers used included MRSM, XM and TM—see Table 6). Control samples treated only with buffer and treated only with the commercial polymers were included (treatments 4, 5 and 6). All tTG treatments were carried out as in Example 1 using 5.0 &mgr;g of transglutaminase per mil of liquor, and were incubated for 2 hours at a liquor ratio of 1:10. All other treatment parameters were the same as in Example 1. All mTG treatments were carried out using 100 &mgr;g of transglutaminase per ml of liquors, and were incubated for 1 hour at a liquor ratio of 1:10. All other treatment parameters were the same as in Example 3. In treatments 2, 7, 9 and 11 (see Table 6) the casein digest (0.5 mg/ml) was incorporated into the wool fibres using tTG (5.0 &mgr;g/ml) prior to polymer treatments. In treatments 3, 8, 10 and 12 (see Table 6) putrescine (2.0 mM) was incorporated into the wool fibres using tTG (5.0 &mgr;g/ml) prior to polymer treatments.

[0102] The polymer treatments were carried out by exhaustion subsequently to the TG-casein digest/putreascine treatments at pH 5.5 and 40° C., according to manufacturer recommendations.

[0103] In treatments 14 and 15 microbial transglutaminase was incubated together with the polymer at pH 5.5, 40° C. for 1 hour.

[0104] The samples were tested for felting shrinkage according to the IWS TM 31, except that the dimension of the samples tested was reduced to 120×100 mm. After drying, all samples were sewn around the edges. Three fabric samples of each experiment were tested for felting shrinkage by washing in an Electrolux Wascator washing machine with ECE standard detergent at 40° C., according to the ISO 5A programme.

[0105] There was a significant improvement in the felting shrinkage on all transglutaminase treated fabrics compared to the buffer only treated control (no TGase added). In particular, the treatment with 5.0 &mgr;g of transglutaminase per ml of liquor delivered an improvement of a gain of strength about 29% compared to the respective control (see Table 6). Treatments 8 (tTG 5 &mgr;g/ml together with 2.0 mM of putrescine followed by the polymer MRSM) and 15 (mTG 100 &mgr;g/ml together with polymer TM) resulted in the greatest improvements in dimensional stability Treatments 8 and 15 shrunk by 12.2% and 11.6%, respectively, and the control treated in buffer alone (no TG, additive or polymer added) shrunk by as much as 49.5%. There is a significant difference between the effects of incorporated putrescine alone (31%) or polymer MRSM alone (25%) and the added effect of applying the polymer after incorporation of putrescine (12.2%). Similarly, there is a significant difference between the effects of mTG alone (36%) or polymer TM alone (26.5%) and the added effect of applying the polymer together with mTG (12.2%).

EXAMPLE 7

Effect of Transglutaminase Mediated Incorporation of Active Compounds into Wool Fibres on the Handle of Wool Fabrics

[0106] Samples of 100% wool single jersey fabric supplied by Cooper & Roe, UK (5 g), were used in this example. A pancreatic digest of milk casein (Tryptone, 1.0 mg/ml) and putrescine (2.0 m) were incorporated into wool fibres using 5.0 &mgr;g/ml of tTGase as in Example 6. A commercial softener (an amino silicone, supplied by Precision Processes Textiles, UK) was added to untreated fabric samples and to samples treated with transglutaminase and an active agent (tryptone and putrescine—see FIG. 7) according to the manufacturers recommendations. Control samples treated only with buffer (without adding TGase) under exactly the same conditions of the tGase treatments (Example 1) and controls treated under the conditions of application of the softener were included. A control treated only with the commercial softener was also included.

[0107] The mTGase treatment was carried out using 100 &mgr;g of microbial transglutaminase per ml of liquor, for 1 hour, 55° C. and pH 5.5, together with the commercial softener. All other treatment parameters were the same as in Example 3.

[0108] A panel of 15 judges assessed the subjective softness of the wool samples (FIG. 7). All panellists assessed the samples according to the same regime. All judges used the same surface of the fabric (they were asked to assess softness by gently rubbing the face of the fabric between the fingers and thumb, trying to use the same pressure on all samples). The softer the fabric would feel, the higher the score given. Panellists were asked to score the fabrics from 1 (not soft) to 10 (extremely soft), comparing to the control fabric (treated in buffer alone without adding TGase additive or polymer), which was assigned a score of 5. The results shown in FIG. 7 are the mean scores and respective standard deviations.

[0109] The score obtained for the sample treated only with the softener was 7.26, very similar to the score of the sample treated with tTGase and tryptone followed by the softener (7.23), and was significantly softer than the control sample treated with buffer alone without adding TGase additive or polymer (5.0). The sample treated with tTGase and putrescine followed by the softener was given a score of 8.39, which was formed to be significantly different from the sample treated only with softener (with 95% confidence level). The sample treated with mTGase together with the softener was found to be the softest, with a score of 9.2 (the difference to the significant sample treated only with softener was significant for a 95% confidence level).

EXAMPLE 8

The Use of Transglutaminase to Extend the Life of a Desired Scent on Wool Fibres

[0110] Samples of 100% wool knitted fabric (supplied by Cooper & Roe, UK) were treated with 5.0 and 20.0 &mgr;g/ml of tTGase as described in Example 1. Controls were treated in a similar manner but without adding tTGase. A commercially available scent (4 ml/l) was also added to each treatment.

[0111] A panel of 12 judges assessed the samples according to the level of residual smell 2 and 5 days after the treatment (FIG. 8). After 2 days, and particularly after 5 days the samples treated with 20.0 &mgr;g/ml of tTGase and the scent were attributed the most intense level of residual smell (after 5 days 11 of the 12 judges classified the treatment with 20.0 &mgr;g/ml of tTGase as being the one with most intense residual smell.). This indicates that TGase extends the life of a desired scent applied to wool fibres.

EXAMPLE 9

Transglutaminase Crosslinking of Fluorescein Cadaverine to Wool Fibres

[0112] Wool fibres with approximately 21 &mgr;m diameter were washed it a solution with 0.5 g/L sodium carbonate and 1.0 g/L non-ionic detergent. The fibres were subsequently treated in a 0.05 M TRIS buffer solution (the pH was adjusted to 8.0 with hydrochloric acid) containing 20 mg of proteinase VIII per g of fibre in a shaker rotating at 100 rpm for 60 minutes at 37° C. The proteolytic reaction was stopped by washing the samples with a non-ionic detergent at pH 5 and then in hot water at 80° C. for 15 minutes. Finally, the samples were rinsed before submitted to further treatment. As a control to the protease treatment, fibre samples were also treated with buffer alone.

[0113] The guinea pig liver TGase was then applied to the Savinase treated and respective buffer control samples at 1.0 &mgr;g of TGase per ml of liquor in a TRIS buffered solution pH 8.5. The liquor also contained 0.5 mM fluorescein cadaverine, 5 mM DTT and 5 mM of calcium ion. The liquor to yarn ratio applied was 1:250. The fibre samples were incubated in a shaker rotating at 100 rpm for 18 hours at approximately 37° C. As a control to the transglutaminase/calcium treatments, fibre samples were treated under exactly the same manner in a solution containing buffer, 5 mM DTT and 5 mM EDTA, as a negative control.

[0114] After treatment the fibre samples were first washed in PBS pH 7.4 and 1.0% of Tween 80. Further washing with methanol was carried out to remove non-bound fluorescein cadaverine from the surface of the wool fibres. The samples were then air-dried.

[0115] The treated fibre samples were mounted in 70% glycerol and examined under a confocal microscope. FIGS. 9a and 9b illustrate the pictures obtained from fibre samples submitted to a protease treatment followed by a transglutaminase treatment. It is clear from. FIGS. 9a and 9b that there is a significant difference in the amount of fluorescein cadaverine incorporated by the transglutaminase between positive and negative controls.

[0116] This indicates it is effective to cross-link primary amines with beneficial active groups to wool using tissue transglutaminases.

Claims

1. A method of treating fibrous textile goods comprising treating the fibrous textile goods with an enzyme to either covalently or non-covalently link one or more active functional compounds to the fibres and/or to trap one or more active functional compounds within an inter-fibre matrix and/or within an intra-fibre matrix formed by the action of the enzyme.

2. A method, according to claim 1, wherein the fibrous textile goods are derived from wool or animal hair, optionally blended with one or more cellulosic or synthetic fibres.

3. A method, according to claim 1 or 2, wherein the enzyme is a transglutaminase.

4. A method, according to claim 3, wherein the transglutaminase is a calcium-dependent transglutaminase.

5. A method, according to claims 3 or 4, wherein the transglutaminase is a tissue (type II) transglutaminase.

6. A method, according to any one of claims 3 to 5, where the transglutaminase is a recombinant transglutaminase.

7. A method, according to any one of claims 3 to 6, additionally comprising the step of treating the fibrous textile goods with a protease.

8. A method, according to any preceding claim, wherein the active agent is first bound to a protein or protein fragment, prior to treating the fibrous textile goods.

9. A method, according to any one of claims 3 to 8, wherein the transglutaminase is used together with a primary amine-containing compound.

10. A method, according to claim 9, wherein the primary amine-containing compound has a chemical moiety of general formula —R′NH2 group, wherein R′ is an aliphatic hydrocarbon chain containing between 1 to 8 carbon atoms.

11. A method, according to claim 9 or claim 10, wherein the primary amine-containing compound comprises at least two amine groups.

12. A method, according to claim 11, wherein the primary amine-containing compound is putrescine.

13. A method, according to claim any one of claims 10 to 12, wherein the —R′NH2 group is linked to an active group which imparts further one or more functionalities to the fibres.

14. A method, according to claim 13, wherein the further functionalities are used to bind a second active agent to the fibres.

15. A method, according to any preceding claim, wherein the active agent is a perfume, insect repellent, dyeing agent, softening agent, water repellent antimicrobial agent or sunscreen.

16. A method, according to claim 15, wherein the active agent is an intact protein, hydrolysed protein or modified hydrolysate of a protein.

17. A method, according to claim 16, wherein the protein or hydrolysed protein is keratin, silk, casein, fibronectin or collagen.

18. A method, according to any one of claims 3 to 17, wherein the transglutaminase is used as a level of 0.5-10.0 &mgr;g of enzyme per ml. of treatment liquor.

19. A method, according to any preceding claim, wherein the textile goods are treated with a reducing or oxidated agent prior to treatment with enzyme.

20. A method, according to claim 19, wherein the reducing agent is sodium sulphite, dithiothreitol, 2-mercaptoethanol or glutathione.

21. A method of protecting fibrous textile goods derived from wool or animal hair from attack by a biological detergent comprising treating the fibrous textile goods with an enzyme to covalently cross-link one or more fibres of the fibrous textile goods.

22. A method according to claim 21, wherein the enzyme is a transglutaminase.

23. A method of treating fibrous textile goods to improve dimensional stability and/or improved yarn strength and properties comprising treating the fibrous textile goods with a calcium-dependent transglutaminase.

24. A method, according to claim 23, wherein the fibrous textile goods are additionally treated wilt a protease.

25. Fibrous textile goods obtainable by a method according to any preceding claim.