Post-process:
It is a technical treatment method that gives the fabric a color effect, a morphological effect (bright and clean, suede, crisp, etc.) and a real effect (impermeable, no felting, no ironing, no moth, flame resistance, etc.). The finishing of the fabric is done by chemical Or the main physical method to improve the appearance and feel of the fabric, enhance the wearing performance or give special functions to the process, which is the “icing on the cake” processing process of textiles.
Finishing methods can be divided into two categories: physical/mechanical finishing and chemical finishing. According to the purpose of finishing and the different effects produced, it can be divided into basic finishing, appearance finishing and functional finishing.
Purpose of finishing:
- Make the width of textiles uniform and stable in size and shape. Such as (tensioning), mechanical or chemical shrink-proof, anti-wrinkle and heat setting.
- Improving the appearance of textiles: including improving the gloss and whiteness of textiles, and enhancing or weakening the fluff on the textile surface. Such as whitening, calendering, electro-optical, Yawen, sanding, shearing and shrinking.
- Improve the feel of textiles: chemical or mechanical methods are mainly used to make textiles have a comprehensive touch feeling such as soft, smooth, plump, stiff, thin or thick. Such as softness, stiffness, weight gain, etc.
- Improve the durability of textiles: chemical methods are mainly used to prevent damage or erosion of fibers by sunlight, atmosphere or microorganisms, and extend the service life of textiles. Such as anti-moth, anti-mold finishing and so on.
- Give textiles special properties: including making textiles have certain protective properties or other special functions. Such as flame-retardant, anti-bacterial, water-repellent, oil-repellent, anti-ultraviolet and anti-static.
The development of fabric finishing technology is toward product functionalization, differentiation, high-grade, diversification and in-depth processing of processing technology, and emphasizes improving the wearability of the product and increasing the added value of the product. In recent years, various new technologies (such as low-temperature plasma treatment, bioengineering, ultrasonic technology, electron beam radiation treatment, inkjet printing technology, microcapsule technology, nanotechnology, etc.) have been introduced and borrowed from other technical fields to improve processing Depth, get a good finishing product. As human beings pay more and more attention to environmental pollution and destruction, they are paying more and more attention to health, advocating a “low-carbon” economy, and finishing technologies require environmentally-friendly “green” processing to produce “clean” and “low-carbon” textile products.
The basic finishing methods of fabrics include: stabilizing size, improving the appearance of finishing methods, improving the feel and optimizing performance of finishing methods, making the fabrics multi-functional and high value-added finishing methods, making the fabrics advanced finishing methods, and meeting special requirements Sorting method.
Various finishing processes are as follows:
1 pre-shrink
Pre-shrinking is a process that uses physical methods to reduce the shrinkage of the fabric after soaking in water to reduce the shrinkage rate. Mechanical preshrinking is the process of spraying steam or spraying to wet the fabric, and then applying warp mechanical squeezing to increase the buckling wave height, and then dry it loosely.
2 stenter
Tenting is a process that uses the plasticity of cellulose, silk, wool and other fibers under humid conditions to gradually widen the width of the fabric to a specified size for drying, so that the shape of the fabric can be stabilized. It is also called fixed-width finishing.
3 sizing
Sizing refers to the finishing process in which the fabric is dipped into the slurry and dried to obtain a thick and stiff effect.
4 heat setting
Heat setting is a process that makes the morphology of thermoplastic fibers and blended or interwoven fabrics relatively stable. It is mainly used for the processing of synthetic fibers such as nylon or polyester that are easy to shrink and deform after being heated and their blends. The heat-set fabric can improve the dimensional stability and feel more stiff.
5 whitening
Whitening is the process of increasing the whiteness of textiles by using the principle of complementary colors of light, also known as whitening. There are two kinds of whitening methods: blue and fluorescent whitening.
6 Calendering, electro-optic and embossing
Calendering is the process of making use of the plasticity of the fiber under humid and hot conditions to flatten the surface of the fabric or make parallel fine twills to enhance the luster of the fabric. Flat calendering consists of hard rolls and soft rolls. After the fabric is rolled, the yarn is flattened, the surface is smooth, the luster is enhanced, and the hand feels stiff. Soft calendering consists of two soft rolls forming a soft nip point. After the fabric is rolled, the yarn is slightly flat, with a soft luster and a soft hand.
Electro-optical is the use of electrically heated rollers to calender the fabric.
Embossing is composed of steel rolls and soft rolls engraved with positive patterns. Under hot rolling conditions, the fabric can obtain shiny patterns.
7 sanding, sanding
The process of using a sanding roller (or belt) to grind a layer of short and dense fluff on the surface of the fabric is called sanding, also known as sanding. The sanding finishing can make the warp and weft yarns produce fluff at the same time, and the fluff is short and dense.
8 fluffing
Fuzzing is the process of picking up the fibers on the surface of the fabric with dense needles or thorns to form a layer of fluff. It is also called brushing finishing. Fuzzing is mainly used for woolen fabrics, acrylic fabrics and cotton fabrics. The fluff layer can improve the warmth of the fabric, improve the appearance and make the hand feel soft.
9 Shearing
Shearing is the process of using a shearing machine to cut the unwanted hair on the surface of the fabric. Its purpose is to make the fabric weave clear and the surface smooth, or to make the pile or pile surface of the raised and raised fabrics neat. Generally woolen, velvet, artificial fur, carpets and other products need to be sheared.
10 soft
There are two methods for soft finishing, mechanical finishing and chemical finishing. Mechanical soft finishing is achieved by rubbing and bending the fabric many times, and the softening effect after finishing is not ideal. Chemical softening is to apply a softener on the fabric to reduce the coefficient of friction between the fiber and yarn, so as to obtain a soft and smooth hand feeling, and the finishing effect is significant.
