![]() Scouring is an important operation by which natural impurities (greases, waxes, fats etc.,) and acquired impurities from the fabric are removed. PVA can also be recovered by applying nano-filtration or ultra filtration. ![]() Polyvinyl alcohol can be easily removed if washing is carried out at higher temperatures (near boiling point). If polyvinyl alcohol (PVA) or carboxy methyl cellulose (CMC) is used for sizing, they are removed with a detergent/water solution as they are readily soluble in water. Peroxide fully degrades starch to CO and HO. In recent times, peroxide is also employed for desizing. Then the clothes are subjected to mild acid treatment and rinsed well with water. The enzymes hydrolyse starch and converts it to readily soluble sugars. In this method, the cloth is steeped in baths containing enzymes and kept for 4 to 8 hours at 55 to 80 0C. When modified starch is employed for sizing, desizing with enzyme is preferable. The greige cloth is treated with dilute sulfuric acid (0.5%) at room temperature for a period of 4 to 12 hours and then washed well. In these two methods, starch molecule is broken down and converted to more soluble materials and thus its removal is facilitated. If starch is used as the sizing agent, the following two methods are employed for its removal. The methods and chemicals used for desizing depend on the type of sizing agent used. If the sizes are present, they may hinder dyeing, printing and finishing processes. It is a process employed to remove the sizing materials present in the greige cloth to make it suitable for further processing. They are very soluble in water and hence can be removed easily from the fabric. Among these sizes, polyacrylates are exclusively used for sizing nylon and polyester. The other sizing compounds, namely, gelatin, oil, polystyrene, polyacrylates (of sodium and ammonium salts), and polyacetates are employed for sizing synthetics. (Carboxy methyl cellulose has twin advatages: (i) warps sized with CMC can be woven at lower humidities, and (ii) when CMC is used for sizing, desizing becomes much easier as the CMC film readily dissolves in water). The important sizing agents used for cotton sizing are polyvinyl alcohol (PVA) and carboxy methyl cellulose (CMC). These synthetic sizes provide enhanced performance and can be easily removed by desizing. However the trend is now changing and starches are slowly replaced by synthetic sizes. Native starch and modified starches are extensively used for sizing hitherto. It is the cheapest and effective sizing agent. Starch is the traditional sizing agent exclusively used for cotton fabrics. It is the process by which warp thread is sized with starch (or other synthetic sizing materials) to give necessary tensile strength and smoothness required for weaving. Fig: Wet processing in textile industry Stages of Wet Processing in Textile Industry In this article, I will discuss all above stages of wet processing in textile industry and it is for the cotton materials. Wet processing in textile industry is one of the most important part of textile processing. Finishing operations are mostly wet processes and they include desizing (removal of the added size compounds), scouring/kier boiling, bleaching, mercerizing, dyeing/printing and final finishing. Slashing or sizing is the process in which certain natural or synthetic compounds are applied to yarns to bind the fibers together and stiffen the yarn to provide abrasion resistance during weaving. Most of the weaving operations are carried out under dry conditions, except slashing. RF, PLC, CAD, HW Startups, Robotics, Microcomputing, DIY Audio, DIY Gear, DIY, Mindstorms, ASM, EE Books, Product Design, LabVIEW, Breadboard, RTLSDR, Manufacturing, Electronic Circuits.Cotton processing consists of two basic processes namely, weaving and finishing. AskElectronics, Electronics, ECE, RPi, NiceChips, DevKit, Arduino, micro:bit, Nucleo, STM32F4, MSP430, PSoC, ARM, Amp Hour, FPGA, DSP,. ![]() How to solder: SMD Resistors, SMD ICs, SMD QFP IC, SMD Drag Solder, SMD Tips, 1980 Soldering Videos.Online: Ucamco, GerbLook, EasyEDA, MayhewLabs. Gerbv, GerberLogix, DFM Now, ViewMate, ZofzPCB, GC-Prevue, RefGerbView. Pro ($$$$): Altium, Allegro, OrCAD, PADS, Xpedition. WIKI / FAQ / PCB Review Tips / 3D models / SPICE models / Book ListĮagle, Fritzing, Horizon, KiCad, LibrePCB, ( Comparison).Links within /r/PrintedCircuitBoard subreddit: This subreddit isn't meant for repairing PCBs. Official Printed Circuit Board Subreddit - schematic capture / PCB layout / gerber / review / electronics assembly / circuit simulation.
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