A good bleach should have the following properties. After desizing the cotton fabric is subjected to scouring operation. Some finishes change the look and feel of the cotton fabric, while others add special characteristics such as durable press, water repellency, flame resistance, shrinkage control and others. Mercerizing of cotton is done in three basic stages of materials. There are three types of technique in desizing and four method of desizing that has been used in wet processing. Process of cotton textile materials desizing different. The aim of this work is the development of a comprehensive concept for the enzymatic. Single stage process for desizing, scouring, and bleaching.
After conducting desizing with atmospheric pressure plasma treatment, the cotton denim fabric was subjected to an enzymatic colour fading process. Onestep process for enzymatic desizing and bioscouring of. Bleaching is a process by which the natural coloring matter and any other colouring matter is removed from natural fibers which are responsible for diminishing the fabric whiteness. Dilute acid converts starch into water soluble compound and removes it. After passing fabric from desizing solution fabric is batched for 812 hours.
The most important aspects of oxidizing agents are that they can be applicable to wide range of fabrics, the size content of which is often not known. The finish is temporary with starch or wax, and durable with resin. Feasibility study of integrated desizing, scouring and bleaching of cotton woven fabric with h2o2 and investigation of various physical properties with traditionally treated fabric. A clean fabric will ensure that the next wet process can be done without interference from unwanted residual components. Through the orthogonal experiment, the optimum process conditions of conventional enzyme desizing process and ultrasonic enzyme desizing process were. E nzymes are complex organic, soluble biocatalysts, formed by living organisms, that catalyze chemical reaction in biolo gical pro cesses. Onestep process for enzymatic desizing and bioscouring of cotton fabrics article in journal of natural fibers 72. Continuous bleaching process with cbr bleaching machine. Textile fibers and their classification textile course. Finally cold wash is carried out and then squeezed and dried.
Textile wet processing is one of the most polluting industrial processes. Sizing agents are selected on the basis of type of fabric, environmental friendliness, ease of removal, cost considerations, effluent treatment, etc. The process variables were chosen according to the box behnken method of statistical tool for process optimization. The scouring process consists of treatment of cotton fabric under alkaline conditions at high temperature. Most of the companies offer 23 types of desizing enzymes that can be used for different temperature and ph. This article has presented the process sequence of wet processing for cotton goods or fabric. The process, which may be applied at the yarn or fabric stage, involves immersion under. It is a complex process, and its complexity depends on the composition of textile material. Cotton is still the king of fibers because most of the worlds apparel is made of cotton. The process, which are done to make the textile mtl suitable for dyeing. Reactive dye are so called because their molecules react chemically with the fiber polymers of some fiber to from a covalent.
After dyeing or printing of singed fabric, brightness and luster of the color and fabric becomes better. Fabric should be dry, fabric component should be clean, power failure must be checked, electromagnetic device should be checked, speed should be the same. Oxidative desizing desizing with oxidizing agents though the use of oxidants for desizing of cotton fabric is widely accepted but their large scale industrial application is yet to be exploited. May 03, 2014 for example, if the desizing liquor is stronger, the process can be completed in a short time so much so that the process can be made a continuous one. Pdf application of corona discharge on desizing of. Cotton fabrics are probably finished in more different ways than any other type of fabrics. The process involves a novel bleaching agent, sodium perborate, spb which was used a lone without any additives in the.
Desizing is the process or removing the starch or size the covering the warp yarn using enzyme. This process is applied on textile in form of liquid with involves some for chemical action on the textile. Application of corona discharge on desizing of polyvinyl alcohol on cotton fabrics article pdf available in journal of applied polymer science 1145. The conventional reactive he dyeing process is explained through time vs. The cotton plants root system is very efficient at seeking moisture and nutrients from the soil. The inputs and outputs of the conventional pretreatment process viz. Tt315 chemical processing of textiles labi pdf book. For woven fabrics, the size applied to the warp yarns during weaving can interfere with the penetration and fixation of print color. This inspecific alkaline scouring process has a high energy, water and alkali consumption and can also cause a damage of the cellulosic material. Advantages and disadvantages the acid steeping process is less time consuming than the rot steeping process. Flow chart of wet processing for cotton fabric textile. Effect of atmospheric pressure plasma treatment on the.
It is considered as one of the oldest natural materials used to make fabric. Teliand tesfaye tolessa adere institute of chemical technology, matunga e, mumbai 400019, india abstract now days, all research efforts in the field of wet processing of textiles are directed towards sustainable process through chemical substitution. Then the fabric is immersed into the desizing liquor. A combined desizing, scouring and bleaching of medium and fine varieties of cotton fabrics was sug gested by parikhi, which involves the use ofdtpa as stabilizer for hydrogen peroxide. Pretreatment of fabric before dyeing it is the process of removing starch materials present in the grey fabric. In desizing process of cotton fabric can be accomplished by physical, chemical or combination of physical and chemical mechanism. A process to remove the sizing material from the fabric is called desizing. The desized fabrics were then subjected to dyeing using reactive dyes yellow he6g and navy blue her, where analogous dyeing and fastness. The process by which the textile mtls are treated associated with water is called wet processing. Short and efficient desizing and scouring process of. Af ter dyeing and finishing, the woven material is ready for delivery either directly to manufacturer of textile products where they are finally stitched into clothes. Grey cotton fabric contains natural impurities as well as size added to the fabric to facilitate weaving.
Download tt315 chemical processing of textiles labi book pdf free download link or read online here in pdf. To accelerate dye and chemical absorption of the fabrics. The physical properties like whiteness, percent loss in fabric weight, tensile strength of the treated fabric have been compared with those of the fabric treated to conventional desizing, scouring and bleaching process. Desizing is done in order to remove the size from the warp yarns of the woven fabrics. Sizing and desizing of cotton and polyester yarns using. The process variables were chosen according to the boxbehnken method of statistical tool for process optimization. Short and efficient desizing and scouring process of cotton. Explain various operations in different departments in a. As a whole this process consist of desizing process, scouring and bleaching. Pdf desizing of untreated cotton fabric with the conventional and. A study on enzymatic treatments of unscoured cotton fabric.
Several different finishes may be applied to a single fabric. The auxiliary devices of ultrasonic treatment was designed and manufactured. Mercerization process of cotton fabric textile learner. All books are in clear copy here, and all files are secure so dont worry about it. Desizing is the process of removing sizing materials from the fabric, which is applied in order to increase the strength of the yarn which can withstand with the friction of loom.
Cleaner production technologies in desizing of cotton fabric taylor. Mercerizing of cotton fabric methods of mercerizing process. Desizing of a grey fabric can also be done by using alkali and oxidising agents. Desizing removal of protective starch coating o scouring cleaning o bleaching whitening o singeing and shearingremoval of protruding fibers o tentering alignment of yarns in a fabric o calendering pressing o mercerization caustic soda treatment of cotton o fulling shrinkage treatment of wool. Carding cardingcarding is the process of taking rough, raw fibers and detangling and straightening them.
The process basically consists of boiling the cotton fabric with strong alkali and detergent at high temperature. Fabric which has not been desized is very stiff and causes difficulty in its treatment with different solution in subsequent processes. Desizing cotton material is desized to remove the sizing material that is applied to the gray yarn and to become free of the added matter for effective scouring and bleaching. The resultant performance properties were also compared. Enzymes are complex organic, soluble biocatalysts, formed by living organisms, that catalyze chemical reaction in biological processes. Acid steeping is a risky process and may result in the degradation of cotton cellulose while rot steeping, hot caustic soda treatment and hot washing with detergents are less efficient for the removal of the starch sizes. If weaker solutions are used, the process is bound to be batch one.
The main disadvantage is that there is no control over the process. Introduction cotton is the leading fibre in textile industry. Desizing process in textile industry fashion2apparel. Desizing is one of the key processes for the pretreatment of cotton fabric. In this work, we demonstrate a completely green and economically viable sizing and desizing process for cotton and polyester yarns using liquid and supercritical co2 as alternative solvent systems and inexpensive, nonfluorous co2philes as size compounds. Cotton fabric, enzyme, desizing, bioscouring, bleaching, sustainable process. There are mainly 3 divisions of wet processing i pretreatment. The cotton fabric was desized using 2000l desizing enzyme with the conventional enzyme desizing process and ultrasonic enzyme desizing process respectively. Enzymatic desizing of starches on cotton fabrics oxidative desizing acid desizing removal of water. Mercerization is a process applied to cotton and sometimes to cotton blends to increase lustre thus also enhancing appearance, to improve strength, and to improve their affinity for dyes. Materials chemical required greige cotton fabric yarn, hydrochloric acid or sulphuric acid and water desizing procedure. Starch is widely used as a sizing agent, being readily available, relatively cheap and based on natural, sustainable raw materials.
Natural cotton, after weaving and washing, is an offwhite color like a light shade of ecru or cream. The purpose of a desizing process is to remove sizes that have been attached to warp yarns during a weaving process. A process for desizing of a sized fabric containing starch or starch derivatives during manufacture of a fabric, which process comprises incubating said sized fabric in an aqueous treating solution having a ph in the range between 1 and 5 which aqueous treating solution comprises an alphaamylase. Flow chart of wet processing for cotton fabric textile chapter. Normally, if the fabric is to be dyed, it goes straight to the dyer at that point. Woven fabric can be thought of as a threepart system.
During this time starch is converted from insoluble starch to soluble alphaglucose. The most commonly used methods for cotton are enzymatic desizing and oxidative desizing. The optimum desizing in terms of weight loss% and tegewa violet scale was obtained at 60 c, ph 56 for 30 min in the presence of 4. Jul 29, 2015 oxidative desizing desizing with oxidizing agents though the use of oxidants for desizing of cotton fabric is widely accepted but their large scale industrial application is yet to be exploited. The flow diagram of the fibre to fabric process is shown in figure 1. Introduction cotton grows on the seeds of the cotton plant and is one of the most recognized textiles in the world. After desizing, the fabric is squeezed and stored in a storage tank. As has been seen so far, tensionless mercerization is a process in which the fiber is freely allowed to swell and shrink due to alkali absorption without any tension being applied, and after the alkali is washed off, dimensions are set, and is a process from which a stretch cotton with around 20% elasticity can be attained, using a fiber which. If it is to be sold as bleached fabric or made into white clothing, it is first bleached, washed, then often treated with optic whiteners and washed again. The mechanical, chemical and dyeing properties of the ozonized fabric have been compared with those of the fabric subjected to conventional desizing, scouring and hydrogen peroxide bleaching.
Read online tt315 chemical processing of textiles labi book pdf free download link book now. Desizing is the process of removing the size material from the warp yarns in woven fabrics. Pretreatment of textiles prior to dyeing edward menezes and mrinal choudhari rossari biotech ltd. With regard to manmade fibers, which are generally white. Through the orthogonal experiment, the optimum process conditions of conventional enzyme desizing process and ultrasonic enzyme desizing process were determined. Changes occurring of cotton fiber during scouring process. Combined desizing, scouring and bleaching of cotton using ozone. The process on small scale sector is also known as boiling. Pdf feasibility study of integrated desizing, scouring. To remove noncellulosic substance in case of cotton.
It is a process of coloring fibers, yarns, or fabrics with either natural or. Btra developed a singlestage process in kier which is claimed to produce high degree of whiteness with minimum damage to cellulose2. Saponifiable oils and free fatty acids are converted into soaps. From this point of view, new efficient strategies for cotton wet processing are. The size is added to grey fabric in a weaving preparatory process called sizing. Desizing, irrespective of what the desizing agent is, involves impregnation of the fabric with the desizing agent, allowing the desizing agent to degrade or solubilise the size material, and finally to wash out the degradation products. Sustainable processes for pretreatment of cotton fabric.
Woven fabric finishing woven fabric finishing includes preparation of the cloth desizing, scouring, bleaching and mercerising, dyeing, printing and finishing resin treatment, waterproofing or flameproofing and. Study on the enzyme desizing process for cotton fabric using. Reuse of bleach bath cotton and cotton blend preparation are performed using continuous or batch processes and usually are the largest water consumers in a mill. Warp yarns are coated with sizing agents prior to weaving in order to reduce their frictional properties, decrease yarn breakages on the loom and improve weaving productivity by increasing weft insertion speeds. After recycling the scouring and bleaching process water three times, the baths still contain 55 % alkali and 67. Scouring of cotton fabric 1introduction scouring of cotton fabric is a chemical washing process with the aim of removing impurities that may appear in raw cotton such as oils, fats, waxes and other impurities. The effects of the ozone desizing and combined conventional desizing and scouring on tear strength and abrasion resistance of 100% cotton terry fabrics turhan y 1 and soydas s2. A fiber that can be spun into yarn or processed into textile such as a woven fabric, knit fabric, lace, felt, nonwoven etc by means of an appropriate interlacing method is called as textile fiber. Reuse of scouring and bleaching process water for desizing. The focus is on the following three specific sectors of the textile industry all of which process cotton, wool and synthetic fibres. In desizing, the starches and polymers that are applied which are insoluble, are converted into water soluble corn pound to ease their removal. First fibers are made into yarn, then the yarn is woven in various ways to become fabric. The colour fading effect was found to be more significant when compared with the conventional enzymatic colour fading process.
Short and efficient desizing and scouring process of cotton textile materials mangesh d. Sustainable processes for pretreatment of cotton fabric springerlink. However for light and medium shades or when fiber brightness is important, bleaching becomes an essential operation before dyeing or printing. Acid steeping is a risky process and may result in the degradation of cotton cellulose while rot steeping, hot caustic soda treatment and hot washing with detergents are. Coldpadbatch biopretreatment of cotton woven fabrics. Kr8104 that is highly active under acidic conditions. Therefore, desizing the removal of warp size becomes.
Enzymatic desizing for effective processing processing. This water soluble product could be easily washed out in actual practice. Material safety data sheet for u s a and european union 1. From an economic standpoint, cottons water use efficiency allows cotton to generate more revenue per gallon of water than any other major field crop. This process is used on woven fabrics but not on knitted fabrics. An attempt has been made to desize, scour and bleach grey cotton fabric simultaneously using ozone. A closedloop process for cotton fabric preparation desizing, scouring, bleaching that is environmentally safe was devised. The added matter or size is removed from the fabric by a process called desizing. Desizing of cotton fabric can be accomplished by physical, chemical or. Both sides of the fabric is burnt out by the flame, it helps in subsequent chemical process of the fabric. The efficiency of a treating bath formulation consisting of h 2 o 2, sodium hydroxide, chelating agents, wetting agent, metal ions, and mgso 4 7h 2 o in effecting combined desizing, scouring, and bleaching of cotton fabric using a winch beck system was investigated under different conditions. The organic cotton sized fabrics were treated with alphaamylase with various process variables such as enzyme concentration, temperature and reaction time. Enzymes are quite specific in their action on a particular substance.
Enzymatic desizing is the classical desizing process of degrading starch size on cotton fabrics using enzymes. Pfd prepared for dyeing rtd ready to dye definitions. Combined desizing, scouring and bleaching of cotton. The fabric should be washed with hot water after desizing. Therefore the local production of cotton desizing enzyme will no doubt be a. The residual size on the warp yarns can resist subsequently applied dyes and chemicals, therefore, it needs to be removed before any subsequent wet processing of the fabric. Study on the enzyme desizing process for cotton fabric. Pdf an investigation of the concentration and performance of.
Since, acid can attack cellulose care has to be taken to avoid damaging the cotton. The total starch present in the grey fabric was calculated by hydrolyzing the starch with h 2 so 4 0. Desizing is a process of removing the sizing agents covering the warp yarns prior to the finishing process because the sizing agents will lead to uneven dyeing, printing or finishing due to the sizing agents ability to act as waterproofrepellent barrier. Bleaching is enough for prepared the fabrics for dyeing and printing but mercerizing is done for adding some advantage to the fabric. The desized fabric can be used in wet condition or dry condition. Luster and strength of the fabric increases for mercerizing process.
In enzymatic desizing the grey fabric is first padded with the desizing mixture. Prior to the desizing process, therefore, the size analysis should be performed in order to set desizing conditions suitable for the sizes. The aim of this study was to investigate the effects of ultrasound on textile pretreatment processes. In this method cotton fabric is treated with dilute sulfuric acid with a concentration of 510 gl at a temperature of about 40c for 34 hrs. Then, the desizing enzyme mixture is added to the padding mangle.
To remove natural color and make the fabric for next process. Us2974001a us748784a us74878458a us2974001a us 2974001 a us2974001 a us 2974001a us 748784 a us748784 a us 748784a us 74878458 a us74878458 a us 74878458a us 2974001 a us2974001 a us 2974001a authority us united states prior art keywords fabric bleaching liquor desizing grams prior art date 19570720 legal status the legal status is an assumption and is not a. The quality of fabric that has been cold bleached does not have to be different from any other bleach process. Immobilized enzyme can be use many times which enables to improve environment friendly pretreatment processes for the textile industry. Cotton based woven fabric encompasses desizing of the sizing elements starch, polyvinyl alcohol etc are usually applied on warp yarns to avoid breakages during weaving process, alkali scouring to take out the natural impurities such as fats and waxes, pectines and proteins followed by a hypochlorite or hydrogen peroxide bleaching process.