Steps of Wet Processing Technology

Steps of Wet Processing Technology Prepared By : Prepared By : Mazadul Hasan sheshir ID: 2010000400008 th 13 Batch (session 2009-2013) Department : Wet Processing Technology Email: mazadulhasan@yahoo.com Blog : www Textilelab.blogspot.com (visit) Southeast University Department Of Textile Engineering I/A 251,252 Tejgaon ,Dhaka Bangladesh Total Textile Process at a Glance Wet processing Singeing    Desizing    Scouring Process There are two types of textile scouring processes – Conventional scouring process: • • • Kier boiling (discontinuous) scouring Scouring in J or L box (continuous) Exhaust method Special scouring process: • • Solvent scouring process Vapor lock scouring proces General recipe for scouring for Kier boiler process: •Alkali (NaOH) - 2 to 5 gm per Litre.  •Soda ash - x gm per Litre to adjust PH (PH required for scouring is 10.5).  •Wetting agent - 1 gm per Litre.  •Sequestering agent - 1 gm per Litre.  •Detergent - 1 to 2 gm per Litre.  •Temperature - 100 to 1250c.  •Time - 6 hours (close vessel) and 8 hours (open vessel)  •M : L - 1 : 10  Description and Working Principle of Scouring Process:  Kier boiler is a long mild steel or cast iron cylindrical vessel provided with two perforated tube sheets (disc with a number of holes) One is placed at the bottom and another is top These discs are connected by a number of tunes which carry the liquor from the bottom compartment to the upper one In the middle compartment steam is passed Thus the tubes carrying the liquor are surrounded by steam which heats them The hot liquor from the multitublar heater is sprayed over the cloth, packed in the kier, through a hollow perforated ring The liquid passes slowly over the packed cloth, collects below the false bottom, from where it is pumped into the auxiliary heater by a centrifugal pump and the cycle repeats  Figure scouring process Figure of dyeing process TEXTILE PRINTING Textile printing is referred as localized dyeing It is the application of color in the form of a paste or ink to the surface of a fabric, in a predetermined pattern Printing designs onto already dyed fabric is also possible In properly printed fabrics the color is bonded with the fiber, so as to resist washing and friction Textile printing is related to dyeing but, whereas in dyeing proper the whole fabric is uniformly covered with one color, in printing one or more colors are applied to it in certain parts only, and in sharply defined patterns In printing, wooden blocks, stencils, engraved plates, rollers, or silk screens can be used to place colors on the fabric Colorants used in printing contain dyes thickened to prevent the color from spreading by capillary attraction beyond the limits of the pattern or design Figure of printing machine Finishing • • Textile finishing is the term used for a series of processes to which all bleached, dyed, printed and certain grey fabrics are subjected before they put on the market The object of textile finishing is to render textile goods fit for their purpose or enduse and/or improve serviceability of the fabric Finishing on fabric is carried out for both aesthetic and functional purposes to improve the quality and look of a fabric Fabric may receive considerable added value by applying one or more finishing processes Finishing processes include : •Raising •Calendering •Crease resistance •Filling •Softening •Stiffening •Water repellency •Moth proofing •Mildew-proofing •Flame retardant •Anti-static •soil resistance Calendering Calendering is an operation carried out on a fabric to improve its aesthetics The fabric passes through a series of calender rollers by wrapping; the face in contact with a roller alternates from one roller to the next An ordinary calender consists of a series of hard and soft (resilient) bowls (rollers) placed in a definite order The soft roller may be compressed with either cotton or wool-paper, linen paper or flax paper The hard metal bowl is either of chilled iron or cast iron or steel The calender may consist of 3, 5, 6, and 10 rollers The sequence of the rollers is that no two hard rollers are in contact with each other Pressure may be applied by compound levers and weights, or hydraulic pressure may be used as an alternative The pressure and heat applied in calendering depend on the type of the finish required The purposes of calendering are to upgrade the fabric hand and to impart a smooth, silky touch to the fabric, to compress the fabric and reduce its thickness, to improve the opacity of the fabric, to reduce the air permeability of the fabric by changing its porosity, to impart different degree of luster of the fabric, and to reduce the yarn slippage Raising An important and oldest textile finishing is brushing or raising Using this process a wide variety of fabrics including blankets, flannelettes and industrial fabrics can be produced The process of raising consists of lifting from the body of the fabric a layer of fibers which stands out from the surface which is termed as "pile" The formation of pile on a fabric results in a "lofty" handle and may also subdue the weave or pattern and color of the cloth There are to types of raising machine; Teasel machine and Card-wire machine The speed of the card-wire raising machine varies from 12-15 yards per minute, which is 20-30% higher than that of teasel-raising That is why the card-wire raising machine is widely used CONCLUSION Wet processing of textiles constitutes innumerable steps leading to finished product, each having a number of complex variables and every lot is like a new lot and much depends on the well-trained manpower rather than modern machines and technology However, developments are taking place at a rapid pace to satisfy the user with quality product and competitive price Though underlying principle for developments is satisfying user needs This in turn will impart cost competitiveness Then, more functional finishes are also being developed However trend is to use more mechanical finishes than chemical finishes The key to success in textile wet processing technology will be the indication of highly trained manpower at lucrative wages in structured manner http://www.textilelab.blogspot.com  (Visit My Blog for more Info ) My Facebook Textile related Pages 1. Yarn  Manufacturing Technology Link : http://www.facebook.com/pages/Yarn-Manufacturing-Technology/485014954866808 2. Fabric  Manufacturing Technology Link : http://www.facebook.com/pages/Fabric-Manufacturing-Technology/459520217425605 3. Garments  Manufacturing Technology Link : http://www.facebook.com/pages/Garments-Manufacturing-Technology/472364799463126 3. Wet processing  Technology Link : http://www.facebook.com/pages/Wet-Processing-Technology-Dyeing-/468645219825404 4. Fashion-Design-and-Technology Link : http://www.facebook.com/pages/Fashion-Design-and-Technology/587655294583875?ref=ts&fref=ts ... 3. Garments  Manufacturing? ?Technology Link : http://www.facebook.com/pages/Garments-Manufacturing -Technology/ 472364799463126 3.? ?Wet? ?processing? ?? ?Technology Link : http://www.facebook.com/pages /Wet- Processing- Technology- Dyeing-/468645219825404... a wide variety of fabrics including blankets, flannelettes and industrial fabrics can be produced The process of raising consists of lifting from the body of the fabric a layer of fibers which... through a series of calender rollers by wrapping; the face in contact with a roller alternates from one roller to the next An ordinary calender consists of a series of hard and soft (resilient)