The textile industry is fast to adopt new enzymes. It is a fashion-driven industry that is always preparing garments with new looks. Enzymes can provide a tool for supporting new fashions as well as improving the basic processing steps in the making of textiles.
Over recent years, Novozymes has been first with promising new enzymes and applications. Our first real breakthrough came in 1987 when Novozymes discovered a major enzyme application within the treatment of denim jeans.
We discovered that one of our cellulases removed some of the indigo dye from denim and gave the fabric a worn look. Within a matter of three years, almost everybody in the denim finishing industry had heard of cellulases, tried them and was using them. This application based on the enzyme Denimax was the reason for the growth of textiles into a major market for industrial enzymes.
Today, we have a leading position for textile enzymes. Our products are used widely for improving production methods and fabric finishing.
One of the oldest applications in this industry is the use of amylases to remove starch size. The warp (longitudinal) threads of fabrics are often coated in starch in order to prevent their breakage during weaving.
Cellulases have become the No. 1 tool for fabric finishing. Apart from stonewashing with the DeniMax range, the cellulase Cellusoft is used to prevent pilling and improve the smoothness, softness and col-our brightness of cotton fabrics in a process which we call BioPolishing.
Our technologies within bleaching of the textiles are safer environmental wise and damage the fiber much less that existing methods. For example our process in an aqueous medium that provides a bleached look in the color density of the surface of dyed fabric. Another process gives a simultane-ously desizing and bleaching of a sized fabric that contains starch.
The catalase Terminox Ultra is used for degrading residual hydrogen peroxide after the bleaching of cotton. It reduces the rinsing necessary to remove bleach or it can be used to replace chemical treat-ments.
Novozymes? proteases are used for wool treatment and the degumming of raw silk.
Below are a few of our patents covering the textile area. If you are interested in one of the patents or if you are interested in a technology that is not listed here, do not hesitate to contact us for more details or search one of the patent databases for other of our patents.
Title of Technology: Manufacturing a fabric or a garment with a stone-washed or worn look
Abstract: The present invention relates to a method of manufacturing a fabric or a garment with a stonewashed or worn look, without any or very lim-ited strength loss of the fabric. The popularity of a stonewashed or worn look in denim fabrics among customers of all ages has been well documented by sales in a large number of countries throughout the world.
The look is obtained by coating the yarn, fabric or garment with a polymer e.g. xyloglucan prior to dyeing and afte rwards creating the abraded or worn look by enzymatic degradation of said polymer e.g. by using a xyloglucanase. The xyloglucanase is not able to hydrolyse the cellulosic fabric, and hence no strength loss will be obtained.
Detailed Description: A popular look for denim is the stonewashed or worn look. Denim is most often cotton cloth. Traditionally stonewashing has been per-formed by laundering the denim material or garment in the presence of pumice stones. This stonewashed look primarily consists of re-moval of dye in a manner to yield a material with areas, which are lighter in colour, while maintaining the desirable white on blue con-trast, and a material which is softer in texture.
Use of enzymes to stonewash has become increasingly popular be-cause use of stones alone have several disadvantages. For example, stones used in the process cause wear and tear on the machinery, they cause environmental waste problems due to the grit produced and result in high labour costs associated with the manual removal of the stones from pockets of garments. Consequently, reduction or elimination of stones in the wash may be desirable.
Contrary to the use of pumice stones, enzymes are safe for the ma-chinery, result in little or no waste problem and drastically reduced labour costs.
It is an object of the present invention to create an enzymatic process for manufacturing a fabric or a garment with a ?stone-washed? look, a ?worn? look or any other fashion look known in the art based on pro-viding fabric or garments with localized variation in colour density, wherein the used enzyme has no or only a very low activity towards insoluble cellulose. In particular, it is an object to create an enzymati c process by coating the yarn or fabric or garment with a polymer prior to dyeing and afterwards creating the abraded or worn look by degra-dation of the polymer coating.
According to the present invention the first step in this new method of manufacturing a fabric or a garment with a stone-washed or a worn look is to coat the yarn or fabric or garment with a biodegradable polymer. A characteristic feature of the polymer for use in this inven-tion is that it should be able to bind tightly to the surface of the fibers, yarns, fabrics or garments in question. The biodegradable polymer may typically be a xyloglucan polymer, because xyloglucan binds very strongly to cellulose.
Glossary of Terms
| Term: |
Definition: |
| Xyloglucans |
Xyloglucans occur widely in the primary walls of higher plant cells, where they are bound in close association with cellulose microfibrils. Xyloglucans are linear chains of (1®4)b-D-glucan, but, unlike cellu-lose, they possess numerous xylosyl chain units added at regular sites of the O-6 position of the glucosyl units of the chain. According to the present invention xyloglucan obtained from monocotyledons and/or dicotelydons are preferred, in particular tamarind seeds.
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| Fabrics |
The invention is most beneficially applied to cellulose-containing or cellulosic fabrics, such as cotton, viscose, rayon, ramie, linen, lyocell (e.g. Tencel, produced by Courtaulds Fibers), or mixtures thereof, or mixtures of any of these fibres, or mixtures of any of these fibres together with synthetic fibres (e.g. polyester, polyamid, nylon) or other natural fibers such as wool and silk. In particular, the fabric is a twill, preferably denim. |
| Xyloglucanases |
According to the present invention a xyloglucanase is defined as any enzyme which has an activity towards the substrate xyloglucan. Pref-erably the xyloglucanase according to the invention is produced by micro-organisms such as fungi or bacteria |
| Patent Number: |
Title of Patent: |
| US 5914443 |
Enzymatic stone-wash of Denim using xy-loglucan/xyloglucanase |
| EPO 991807 |
Enzymatic stone-wash of Denim using xy-loglucan/xyloglucanase |
| WO 9849387 |
Enzymatic stone-wash of Denim using xy-loglucan/xyloglucanase |
Title of Technology: A process for combined desizing and ?stone-washing? of dyed denim
Abstract: The present invention provides a process for the treatment of fabrics, which process improves the color distribution/uniformity, stone-wash quality, etc., and which reduces the need for after-painting of the fin-ished clothes.
The invention provides a one-step process for enzymatically desizing and stone-washing dyed denim, which process comprises treating the denim with an amylolytic enzyme, such as an a-amylase, in combina-tion with a first abrading monocomponent endoglucanase and a sec-ond streak-reducing monocomponent endoglucanase.
Detailed Description: The present invention relates to a desizing and stone-washing one-step process whereby dyed denim having localized variation in colour density of improved uniformity is achieved by treating dyed denim, especially dyed denim garment such as denim jeans, with an amy-lolytic enzyme and two different endoglucanases in the very same process step.
During the weaving of textiles, the threads are exposed to consider-able mechanical strain. Prior to weaving on mechanical looms, warp yarns are often coated with size starch or starch derivatives in order to increase their tensile strength and to prevent breaking. The most common sizing agent is starch in native or modified form, yet other polymeric compounds, may also be abundant in the size. In general, after the textiles have been woven, the fabric proceeds to a desizing stage, followed by one or more additional fabric processing steps. Desizing is the act of removing size from textiles. After weav-ing, the size coating must be removed before further processing the fabric in order to ensure a homogeneous and wash-proof result. The preferred method of desizing is enzymatic hydrolysis of the size by the action of amylolytic enzymes.
For the manufacture of denim clothes, the fabric is cut and sown into garments, that is afterwards finished. In particular, for the manufac-ture of denim garment, different enzymatic finishing methods have been developed. The finishing of denim garment normally is initiated with an enzymatic desizing step, during which garments are subjected to the action of amylolytic enzymes in order to provide softness to the fabric and make the cotton more accessible to the subsequent enzy-matic finishing steps.
Cotton wax and other lubricants can be applied to yarns in order to increase the speed of cotton weaving. Also waxes of higher melting points are being introduced. Wax lubricants are predominantly triglyc-eride ester based lubricants. After desizing, the wax either remains or redeposits on the fabric and as a result, the fabric gets darker in shade, gets glossy spots, and becomes more stiff.
For many years denim jeans manufacturers have washed their gar-ments in a finishing laundry with pumice stones to achieve a soft-hand as well as a desired fashionable stone-washed look. This abrasion effect is obtained by locally removing the surface bound dyestuff. Re-cently cellulytic enzymes have been introduced into the finishing process, turning the stone-washing process into a bio-stoning process.
The goal of a bio-stoning process is to obtain a distinct, but homoge-neous abrasion of the garments (stone-washing appearance). How-ever, uneven stone-washing (streaks and creases) are very fre-quently occurring. In consequence repair work (after-painting) is needed on a major part (up to about 80%) of the stone-washed jeans that have been processed in the laundries.
Glossary of Terms
| Term: |
Definition: |
| Abrading endoglucanase or cellulase |
An endoglucanase which is capable of providing the surface of dyed denim fabric localized variations in colour density.
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| Monocomponent endogluca-nase |
An endoglucanase which is essentially free from other proteins, in particular other endoglucanases. Monocomponent endoglucanases are typically produced by recombinant techniques, i.e. by cloning and expression of the relevant gene in a homologous or a heterologous host.
|
| Streak-reducing endogluca-nase (or cellulase) or levelling endoglucanase |
An endoglucanase which is capable of reducing formation of streaks usually present on the surface of dyed denim fabric (usually sown into garment, especially jeans) which has been subjected to a stone-washing process, either an enzymatic stone-washing process or process using pumice for providing localized variations in colour density on the denim surface |
Patent References
| Patent Number: |
Title of Patent: |
| EP 1021513 |
A process for combined desizing and ?stone-washing? of dyed denim
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| WO 97182886 |
A process for combined desizing and ?stone-washing? of dyed denim |