Textile preprocessing is an important step in the manufacturing process. The common methods of textile preprocessing including bleaching, dyeing, printing, and finishing, each of them has its advantages and disadvantages.
Textile Preprocessing Methods
Textile preprocessing is the process of cleaning and preparing textile fibers for spinning into yarn or fabric. The most common methods of textile preprocessing are scouring, mercerization, and bleaching. Scouring is a process of cleaning cotton fiber with an alkaline solution to remove impurities such as dirt, oil, and wax. Mercerization is a process of treating cotton fiber with an alkaline solution to make it stronger and more lustrous. Bleaching is a process of using chemicals to whiten textile fibers.
Shedding is to remove lint or fabric from the surface of the fabric and bleaching is the process of removing color from the fabric. Shedding can be done by hand that of a person uses a lint brush, roller, or picker to remove lint by hand; or through a machine, normally called a shedding mechanism that sheds fabric have rotating blades that shave off lint and other debris from the fabric surface.
Bleaching is the process of removing colors or other impurities from a fabric that needs to be proceeded by chemicals or sunlight. Chemical bleaching agents including chlorine, hydrogen peroxide, and sodium hydrosulfite, are used as harsh chemical materials to break down the bonds between molecules. While sunlight bleaching relies on the ultraviolet radiation in sunlight to break down the molecules that give color to fabrics, it is physical bleaching that uses heat or light to destroy the pigments.
The dyeing process can be done with natural dyes or synthetic dyes, with the main purpose is to adding color to a fabric. Natural dyes are made from plant sources, while synthetic dyes are made from petroleum products. Generally, the dyeing is done before printing but can also be done after printing to add different colors to the design.
Printing is the process of applying a design to a fabric that is done with digital or screen printing methods.
Screen printing uses a stencil to apply ink to the fabric, while digital printing uses inkjet or laser printers to print the design onto the fabric. Printing is usually done after dyeing and before finishing.
Finishing is the process of adding treatments to improve the appearance or performance of a fabric. Finishing can include washing, drying, ironing, and coating with chemicals such as flame retardants or water repellents.
Factors that Affect Choosing Textile Preprocessing Methods
1. Textile Fibers
Textile fibers are the raw materials for textile products, which can be categorized into 2 main types: natural fibers and synthetic fibers.
Natural fibers include cotton, linen, wool, silk, and hemp, while synthetic fibers include polyester, nylon, and acrylic.
2. Designs & Types of Fabrics
Fabric design can be a complex process, but it all starts with a basic understanding of the properties of the fabric and how they can be used to create different looks and textures, which makes fabric designing an important part of the textile preprocessing methods of fabrics.
The 3 main types of fabric are woven, knit, and non-woven. Each type of fabric has unique characteristics that must be considered when designing a new fabric. Different types of fabrics require different textile preprocessing methods. The most common type of fabric is cotton. Cotton fabric is pre-shrunk using hot water and steam treatment before it is dyed or printed. This process helps to keep the fabric from shrinking after it is dyed or printed. Other types of fabrics, such as silk, wool, and linen, are not pre-shrunk and must be treated carefully to avoid damaging them during the textile preprocessing stage.
The necessity for textile processing arises from the characteristic impurities and imperfections of textile fibers, and the requirement that, in order to reach the desired performance properties of a fabric, various types of treatments such as warping, shedding, and bleaching must be applied by subsequent manufacturing processes.