Introduction


Contrary to its name, biotechnology is not a single technology. Rather it is a group of technologies that share two (common) characteristics -- working with living cells and their molecules and having a wide range of practice uses that can improve our lives. Biotechnology can be broadly defined as "using organisms or their products for commercial purposes." As such, (traditional) biotechnology has been practices since the beginning of records history. (It has been used to :) bake bread; brew alcoholic beverages, and breed food crops or domestic animals (2). But recent developments in molecular biology have given biotechnology new meaning, new prominence, and new potential. It is (modern) biotechnology that has captured the attention of the public. Modern biotechnology can have a dramatic effect on the world economy and society (3). One example of modern biotechnology is genetic engineering. Genetic engineering is the process of transferring individual genes between organisms or modifying the genes in an organism to remove or add a desired trait or characteristic. This paper deals with the application of modern biotechnology in textile industries.


Unique genetic engineering methods to create new and useful fiber modifying enzymes. Most of our enzyme products are made with genetically engineered organisms. This gives our customers the best economy and functionality possible. American industry spends billions of dollars annually on technology systems to manage waste and capture pollution emissions. Industrial biotechnology--the use of genetically enhanced microorganisms (GEMs) and enzymes--offers a new cost-effective way to prevent the creation of pollution in the first place. Among the report's findings * Biotechnology process changes in the textile finishing sector can reduce water usage by about 17% to 18%. Textile mills may potentially reduce water consumption by as much as 30% to 50% through the use of biotechnology.


The use of enzymes in the textile chemical processing is rapidly gaining globally recognition because of their non-toxic and eco-friendly characteristics with the increasingly important requirements for textile manufacturers to reduce pollution in textile production. Enzymes sources, activity, specificity, reaction, mechanism and thermodynamics, function of textile processing with enzymes, major enzymatic applications in textile wet processing and promising areas of enzyme applications in textile processing... The need is to provide the textile technologist with an understanding of enzymes and their use with textile materials.


Enzymes:


Enzymes are generally globular proteins and like other proteins consist of long linear chains of amino acids that fold to produce a three-dimensional product. Each unique amino acid sequence produces a specific structure, which has unique properties. Individual protein chains may sometimes group together to form a protein complex.


 

Bio catalyst:


Enzymes are biocatalysts, and by their mere presence, and without being consumed in the process, enzymes can speed up chemical processes that would otherwise run very slowly. After the reaction is complete, the enzyme is released again, ready to start another reaction. Most of the biocatalyst has limited stability and over a period of time they lose their activity and are not stable again. Usually most enzymes are used only once and discarded after their catalytic action.


Enzymes differ from chemical catalysts in several important ways


  1. Enzyme-catalyzed reactions are at least several orders of magnitude faster than chemically-catalyzed reactions. When compared to the corresponding uncatalysed reactions, enzymes typically enhance the rates by 106 to 1013 times.


  1. Enzymes have far greater reaction specificity than chemically-catalysed reactions and they rarely form byproducts.


  1. Enzymes catalyze reactions under comparatively mild reaction conditions, such as temperatures below 100C, atmospheric pressure and pH around neutral. Conversely, high temperatures and pressures and extremes of pH are often necessary in chemical catalysis.


Enzymes market:

The industrial enzyme market is divided into three application segments: technical enzymes, food enzymes and animal feed enzymes. The following chart shows the global enzyme markets by application sectors, through 2009.






The major enzymes in this category are enzymes for processing cotton and cellulosic textiles, followed by enzymes for processing leather and fur. The enzyme market for the treatment of silk and wool is minor.




 

Bio-Polishing & Handle Modifier


Bio-polishing is the controlled hydrolysis of cellulose fiber to modify the fabric in way that reduce the pilling tendency and increased the softness of the finishing fabric. The bio-polishing is usually applied under acidic condition (ph 4.5-5.5) at 50 C and just after the bleaching process and before dyeing. The process can be applied after dyeing but due that is unacceptable to the dye house this is not preferred.


Enzyme use for Bio-polishing of cellulose fibers:


Bio-polishing is a biological process in which the cellulose acts on the surface of the fabric. The enzyme molecule is more than a thousand times larger than a water molecule and is therefore too large to penetrate the interior of a cotton fiber. Thus only cellulose fibers are affected near the surface. In the reaction, small fibrils protruding from the cotton fiber surface are weakened. They then easily break off from the surface, making it much smoother than before. The smoothing effect has several benefits: The fiber will have a lesser predisposition towards forming pills and will consequently have a clearer surface structure containing less fuzz. These changes in the fabrics appearance are long lasting because the Cellulose treatment actually modifies the fiber itself, rather than just a coating on the surface. Since it is cellulose, it will function on all cotton substrates such as viscose, flax and ramie, as well as parts of mixed fibers and yarns. Mega Pacific Technology has developed a wide variety of bio-polishing enzymes that can function as both stonewash enzymes and bio-polishing enzymes in various strengths of concentrations.


We also developed various bio-polishing enzymes which maintain good color retention with minimal color loss. Cotton and other natural and man-made cellulose fibres can be improved by an enzymatic treatment called Bio-Polishing. The main advantage of Bio-Polishing is the prevention of pilling. Celluloses hydrolyse the micro fibrils (hairs or fuzz) protruding from the surface of yarn because they are most susceptible to enzymatic attack. This weakens the micro fibrils, which tend to break off from the main body of the fibre and leave a smoother yarn surface. A ball of fuzz is called a 'pill' in the textile trade. These pills can present a serious quality problem since they result in an unattractive, knotty fabric appearance. After Bio-Polishing, the fabric shows a much lower pilling tendency. Other benefits of removing fuzz are a softer, smoother feel and superior colour brightness. Unlike conventional softeners, which tend to be washed out and often result in a greasy feel, the softness-enhancing effects of Bio-Polishing are wash proof and non-greasy. AETL's Sebrite series is much effective to impart pill proof biopolishing on woven and knit cotton fabric and garments. Sebrite also gives high color retention.


 

For cotton fabrics, the use of Bio-Polishing is optional for upgrading the fabric. However, Bio-Polishing is almost essential for the new polynosic fibre lyocell. Lyocell is made from wood pulp and is characterized by a tendency to fibrillate easily when wet. In simple terms, fibrils on the surface of the fibre peel up. If they are not removed, finished garments made with lyocell will end up covered in pills. This is the reason why lyocell fabric is treated with celluloses during finishing. Celluloses also enhance the attractive, silky appearance of lyocell. Lyocell was invented in 1991 by Curtails Fibres (now Acordis, part of Akzo Nobel) and at the time was the first new man-made fibre for 30 years. Addcool series is best suitable for biopolishing of lyocell as it works at pH 5.5 6.0 and temperature 30 45 0C, causing less damage to fabric and high quality finishes.


Advantages of bio polishing:


  • Removes the protruding fibers from the surface
  • No Pilling
  • Provides a smooth and clean look
  • Impart a soft feel to the fabric.
  • Environmental friendly process



Image Courtesy:


  1. cabarrusedc.com


This article was originally published in Textile learner blog run by Mazharul Islam Kiron.