SCOURING Name : MAZADUL HASAN SHESHIR ID: 2010000400008 Batch: 13th Batch (Session 2009-2013) Department: Wet Processing Technology Email: mazadulhasan@yahoo.com Blog: www. Textilelab.blogspot.com Southeast University Department of Textile Engineering PREPARED BY ©right SCOURING Natural fibers contain oils, fats, waxes, minerals, leafy matter and motes as impurities that interfere with dyeing and finishing. Synthetic fibers contain producer spin finishes, coning oils and/or knitting oils. Mill grease used to lubricate processing equipment mill dirt, temporary fabric markings and the like may contaminate fabrics as they are being produced. The process of removing these impurities is called Scouring. Even though these impurities are not soluble in water, they can be removed by Extraction, dissolving the impurities in organic solvents, Emulsification, forming stable suspensions of the impurities in water and Saponification, Converting the contaminates into water soluble components. Definition: The tern scouring applies to the removal of impurities such as oil, wax gum, soluble impurities and solid dirt commonly found in textile material. The process consists essentially of treatment with alkali, a good supply of water is essential. Scouring: Types of Scouring Treatments : 1. Scouring By Chemicals Means 2. Bio scouring or scouring with Enzymes Objects: - The main object of this process is to iron the fabric. 1. To remove natural as well as added impurities of essentially hydrophobic character as completely as possible. 2. To increase absorbency of textile materials. 3. To leave the fabric in a highly hydrophilic condition without undergoing physical or chemical treatment or damage. 4. Remove all natural impurities such as oil , wax , fat etc from the surface of the fabric . 5. Produce the fabric more hydrophilic. 6. Increasing the absorbency and clean the fabric by use alkaline. 7. To make the suitable situation for next bleaching, dyeing, printing, and finishing process. 8. Removing the natural coloring matter of the cotton fabric. Objects Of Scouring: Theory: Scouring is the process which is removes all the natural impurities like oil wax fat etc, from the surface of the fabric and produce the fabric more hydrophilic, Scouring done by using alkali such as NaoH & Na2Co3. Natural impurities of cellulosic fabric are normally removed by boiling off in a strong alkaline solution. The main object of scouring cotton fabrics is to remove natural as well as added impurities of essentially hydrophobic character as completely as possible and leave the fabric in a highly absorptive condition without undergoing chemical or physical damage significantly. 3C17 – COOH + 3NaOH= 3C17H35COONa +3H2O Or Oil + Caustic =Soap + Glycerine There are three types of scouring: Saponification Emulsification Detergency Method: Saponification method is used for this experiment. Theory Of Scouring: SCOURING BLEACHING CURVE Chemical Use Caustic (NaOH) Neutralize acidic materials, saponify glycerides (Waxes and Oils), and solubilize silicate. Sodium Silicate Penetrate and break down lignins in motes. Surfactant Reduces surface tension and minimize interfacial tensions. Detergent Emulsify oils, fats, and waxes; remove oil – borne stains; suspend materials after they have been removed. Chelating (Sequestering) agent Deactivate metal ions. Builder (Salt) Cause detergents to become increasingly effective. Solvent Assist emulsification by dissolving oily materials. Chemical Used and Purpose: Scouring process depends on: - 1. The type of cotton. 2. The color of cotton. 3. The cleanliness of cotton. 4. The twist and count of the yarn. 5. The construction of the fabric. Scouring process depends on: - Yarns and fabrics may be dirty, contain natural waxes or oils, or have been treated with size or lubricants used in spinning, weaving or knitting. These can all interfere with dyeing, often leading to non-level results. Scouring is a large topic, and the process used depends on the fibre type and its condition. “True” scouring of greige cellulosic fabrics is typically done, after desizing, at the boil or at higher temperature in pressure vessels, with as much as 10 grams sodium hydroxide per litre of water, plus surfactants, and the process may last for several hours. Commercial scouring of wool may use solvents, similar to dry cleaning, as part of the process. White fabrics sold at retail have normally be scoured at the mill; “natural” fabrics usually have not (some “natural” fabrics have been scoured but not bleached). SCOURING [...]... illustration of various steps identified to achieve fast and efficient Enzymatic Cotton Scouring process Procedure of Scouring Process: Procedure of Scouring Process: The main processes occurring during scouring are: 1 Saponification of fats into water-soluble soap and water-miscible glycerin under alkaline conditions, 2 Hydrolysis of proteins into water-soluble degradation products, 3 Dissolution of hydrolysis... ammonia of simpler amino compounds, 4 Conversion of pectose and pectin into their soluble salts, 5 Dissolution of mineral matter, 6 Emulsification of unsaponifiable oils and waxes, and 7 Removal of dirt particles from the kier liquor by the detergent present therein Alkaline Enzyme Scouring of Cotton Textiles Alkaline Enzyme Scouring of Cotton Textiles The invention relates to a process for treatment of. .. Smoother surface profile Lesser Weight loss Environmental benefits Lower cost of Auxiliaries AQUEOUS SCOURING Aqueous scouring is the preferred way of scouring fabrics because water is nonflammable, non-toxic, plentiful and cheap When preparing woven goods, the scouring step follows desizing and wet fabric proceed to the scouring range without drying in between The components in the scouring bath must... 1. 0-2 .0 g/l Caustic soda 36°Be……………………………= 1. 0-3 .0 g/l Soda ash……………………………………………= 1. 0-4 .0 g/l Temperature…………………………………… = 9 0-1 00°C Time………………………………………………….= 3 0-6 0 min pH…………………………………………………….= 10.5+ /-0 .5 M:L…………………………………………………… = 1:10 Scouring Procedure: 1 Set the with substrate at room temperature with wetting agent, detergent, sequestering agents, and alkalis 2 Raise the temperature to 9 5-1 00°C @ 1-3 °/min... treatments; temperature, processing time, pH, concentration of reagents, depend on the fibre,whiteness required and on the machine used.Incomplete scouring processes usually originate dyeing and printing defects due to different degrees of wettability and to inconsistent affinity for dyes of the material Scouring of Cotton Scouring of Cotton In the scouring process the cotton cellulose material is treated... ,a 0.1% direct red solution us used A drop of the dye solution is taken by a pipette and put softly on to the sample surface The nature of the absorption is observed carefully Two thinks is considered The time for absorption the drop The shape of the absorbed area on the sample surface Estimation of Scouring: Estimation of Scouring: 1 2 3 Determination of weight loss Absorbency Test • Immersion... fabrics Scouring of Silk Scouring of Silk The scouring of pure silk is a degumming process used to remove sericin (silk gum) from fibroin floss Sericin is the gummy element which keeps together the fibroin floss and gives the silk a hard hand and dull appearance It is carried out on yarn, on dyed yarn, piece-dyed fabric or on products ready for printing The treatment, which causes a loss of weight... for one hour Rinse thoroughly a Batch Scouring Procedure 1 Run fabric in a bath containing : 2 3 Steam fabric one hour at 212F in J-box or steamer Rinse thoroughly at 1600F Blends Blends Scouring fabrics with a blend of fibers requires consideration of the sensitivities of each fiber to scouring chemicals and to process conditions Sensitivities to consider when scouring blends are: Cotton: Resistant... Hydrolysis of proteins into water soluble degradation products Dissolution of amino compounds Solubilising of pectose and pectins by converting into soluble salts Dissolution and extraction of mineral matter Emulsification and solubilisation of natural oils and waxes Removal and dispersion of dirt particles and kitty by the action of alkali and detergent The material after scouring is more... weight ranging between 24 and 28%, gives the degummed silk a lustrous appearance and a soft hand; the treatment is carried out with soapy solutions or with buffer dissolving agents It is also possible to use enzymes (protease), which hydrolyses sericin Scouring of Wool- Synthetics Scouring of Wool On wool, the scouring process removes oils and contaminants accumulated during upstream processing steps . essentially of treatment with alkali, a good supply of water is essential. Scouring: Types of Scouring Treatments : 1. Scouring By Chemicals Means 2. Bio scouring or scouring with Enzymes Objects: - The. Purpose: Scouring process depends on: - 1. The type of cotton. 2. The color of cotton. 3. The cleanliness of cotton. 4. The twist and count of the yarn. 5. The construction of the fabric. Scouring. process of cotton fabrics An illustration of various steps identified to achieve fast and efficient Enzymatic Cotton Scouring process. Procedure of Scouring Process: Procedure of Scouring Process: The