Scouring process~All about textile scouring.

<div dir="ltr" style="text-align: left;" trbidi="on"> <div class="MsoNormal" style="line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="background: white;"><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Fabric that are formed form natural fiber  specially cotton fabric have to subjected a pre treatment process named scouring to remove natural & additive impurities such as oil, wax, fat, hand dust, etc. also to produce a hydrophilic & clean textile material. Scouring is a pre treatment process. It is one of the vital processes of wet processing. On cotton fibers, this treatment removes fatty and pectic substances, softening motes and <o:p></o:p></span></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">preparing the material to absorb the subsequent treatment agents. Also scouring are done in silk and wool fabric. <o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring are done to obtain below advantages<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">1.    To make the fabric highly hydrophilic.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">2.    To remove impurities such as oils, waxes, gum, husks as nearly as possible.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">3.    To increase absorbency of fabric or textile materials without physical & chemical damage.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">4.    To produce a clean material by adding alkali.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">5.    To make the fabric ready for the next process.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">6.    To remove non-cellulosic substance in case of cotton.   <o:p></o:p></span></div> <div class="MsoNormal"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring process depends on:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">1.    The type of cotton.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">2.    The color of cotton.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">3.    The cleanliness of cotton.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">4.    The twist & count of yarn.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">5.    The construction of the fabric.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">6.    The shade% & type of shade of finished product.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Chemicals used in Scouring process:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">  <o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Caustic Soda</b>-  Neutralize acidic materials, saponify glycerides, solubilise silicates.<o:p></o:p></span></div> <div class="MsoNormal" style="line-height: normal; margin-bottom: 16.75pt;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Surfactants- </b>Reduce surface tension & minimize interfacial tension.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Detergents: </b>Emulsify oil, fats, waxes, & remove oil-borne stains.<b><o:p></o:p></b></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Chelating agents: </b>Deactivate metal ions.<b><o:p></o:p></b></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Sodium silicate: </b>Penetrate & break down lignins.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Soda ash: </b>Maintain pH.<b><o:p></o:p></b></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>Sodium silicate: </b>Assist emulsification by dissolving oily materials<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Process that are done in scouring:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal"> <span style="line-height: 115%;"><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">There are three main process done in scouring to remove impurities<o:p></o:p></span></span></div> <div style="background: white; line-height: 21.75pt; margin-bottom: 21.75pt; margin-left: 0in; margin-right: 0in; margin-top: 0in; text-align: justify; text-justify: inter-ideograph;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>i) Saponification :</b> In this process caustic soda are reacted with fats and leads to  formation a hydrophilic soaps. That’s how fats are removed from fiber surface.  <o:p></o:p></span></div> <div style="background: white; line-height: 21.75pt; margin-bottom: 21.75pt; margin-left: 0in; margin-right: 0in; margin-top: 0in; text-align: justify; text-justify: inter-ideograph;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>ii) Emulsification :</b> Wases are esters of higher fatty acids and can not removed via saponification. Also mineral oils, lubricants cannot be removed via saponification. <span style="background-attachment: initial; background-clip: initial; background-image: initial; background-origin: initial; background-position: initial; background-repeat: initial; background-size: initial;">Wax and non saponifiable oils (Non polar) are removed by emulsification as they are immiscible in water (Polar). Normal washing soap  is used as a emulsifying agent which make emulsion of them. </span>Soap generated from the saponification process also act as a emulsifying agent.<o:p></o:p></span></div> <div style="background: white; line-height: 21.75pt; margin-bottom: 21.75pt; margin-left: 0in; margin-right: 0in; margin-top: 0in; text-align: justify; text-justify: inter-ideograph;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>iii) Detergency :</b> Finally, After removal of fats and waxes normal dust and dirt particle have to remove by using a good detergent. <o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring process:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">1.    Batch process.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">2.    Semi-continuous process.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">3.    Discontinuous process.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">4.    Modern process.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: 20.55pt; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring process of cotton:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Generally, there are two principle of cotton scouring.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">1.    Discontinuous (kier boiling process or winch dyeing machine )<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in; text-indent: -.25in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">2.    Continuous (scouring in ‘J’ or ‘L’ box) <o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><br clear="all" /> <o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring process of silk:<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ Impurities present in silk.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ Sericin up to 30% (main impurities)<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Mineral matter, coloring matter, traces of waxes & fats =1-1.5%<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ the removing of these impurities in silk are called degumming.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Scouring of jute :(Bast fiber)<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ Bast fiber, jute, linen etc. multicellular fiber, having polygonal shape. The cells are cemented with each other by lignin which is non-cellulosic unit & is about 11-14%.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ If strong alkali is used for jute scouring, its strength is reduced as lignin is removed & cells are separated. So mild alkali is used in jute scouring at low temperature.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <b><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">Assessment of Scouring:<o:p></o:p></span></b></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <br /></div> <div class="MsoListParagraph" style="background: white; line-height: normal; margin-bottom: .0001pt; margin: 0in; mso-add-space: auto; mso-list: l0 level1 lfo1; text-indent: -.25in;"> <!--[if !supportLists]--><span style="font-family: "georgia" , "times new roman" , serif; font-size: large;"><b>1.<span style="font-stretch: normal; font-variant-numeric: normal; font-weight: normal; line-height: normal;">     </span></b><!--[endif]--><b>Drop test:<o:p></o:p></b></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ In a pipette, a solution of 0.1% direct red or congo red is taken & droplet of solution put on the different places of the fabric. Then the absorption time of the fabric is observed.<o:p></o:p></span></div> <div class="MsoNormal" style="background: white; line-height: normal; margin-bottom: .0001pt; margin-bottom: 0in;"> <span style="font-family: "georgia" , "times new roman" , serif; font-size: large;">ʘ The standard time of absorption of one drop of solution is 0.5-0.8 sec.<o:p></o:p></span></div> <br /> <div class="MsoNormal"> <br /></div> </div>

Scouring process~All about textile scouring.

Fabric that are formed form natural fiber  specially cotton fabric have to subjected a pre treatment process named scouring to remove natu...

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