Knowledge of fabric finishing

1. Make fabric size and shape stable

Tensioning -- the use of cellulose, silk, wool and other fibers in the humid conditions have a certain plasticity, the width of the fabric gradually widened to the specified size and drying stability of the finishing process, also known as the fixed.

Heat setting - refers to the process of heat treating synthetic fabric under certain tension to make its size and shape stable.

2. Improve the appearance of clothing fabrics

Singeing: the fluff on the surface of cotton and its blended textile is removed by direct burning with flame to make the surface smooth and clean, which is convenient for the following processing and ensure the product quality. The temperature of flame is usually 900 ~ 1000℃, and the surface temperature of hot metal plate is 800℃, which is higher than the decomposition temperature or ignition point of various fibers.

Calender finish: through the effect of mechanical pressure, heat and humidity of the calender, the surface fibers are arranged in parallel by means of fiber plasticity, so as to improve the surface smoothness, regular reflection of light, and thus improve the color of the fabric.

Calendering: the calendering machine consists of a hot hard roller and a soft roller. The surface of the hard roller is engraved with Yang pattern, the soft roller is engraved with Yin pattern, the two match each other. By means of the plasticity of the fabric under hot and humid conditions, the fabric is rolled by yin-yang roller to produce concave and convex pattern.

Frosting: the finished fabric can produce suede, feel improved, comfortable to wear, can be done on the raising machine, the fabric by repeated friction to produce suede.

3. Improve the soft feel of clothing fabrics.

Soft finishing is the process of making up for the stiffness and roughness of the fabric. Including mechanical soft finishing, chemical soft finishing and hard finishing.

The mechanical soft finishing mainly USES the mechanical method, under the tension state, to kneading the fabric several times, in order to reduce the rigidity of the fabric, so that it can be restored to the appropriate soft degree.

The chemical method USES the action of a softener to reduce the coefficient of friction between fibers for a softer effect.

Stiffening finish gives the fabric a smooth, firm, thick and plump feel, improves strength and abrasion resistance, enhances body and bone feel and improves appearance.

Stiffening finishing and processing are generally carried out in combination with fixed width. Softener is added into the slurry to improve the comprehensive feel. Similarly, for simple soft finishing, stiffening agent is added to strengthen the fabric body and bone.

4. Improve the durability of clothing fabrics

Mothproof finish

Mothproof finishing AIDS should be highly effective and low toxicity, no side effects on the human body, does not affect the performance of all aspects of the fabric. Common mothproofing finishing methods include wool chemical modification and mothproofing agent finishing.

(1) chemical modification of wool: through chemical modification, a new and stable crosschain structure is formed. When moths eat this crosschain structure, it is difficult to digest and finally kill it, so as to improve the moth prevention performance.

(2) mothproofing finishing method: through finishing, wool fibers are directly carried with chemicals that have killing effect on the moths, which are directly immersed into the skin of the moths or killed by the respiratory and digestive organs.

5. Give fabric special properties

Common are waterproof finishing, water-repellent finishing, flame-retardant finishing.

Waterproof finish is to coat the fabric so that neither water nor air can pass through. Water-repellent finish makes the surface of the fiber hydrophilic to hydrophobic. The fabric is breathable and not easily wetted by water.

Flame retardant finishing, finishing fabric has different degrees of ability to prevent the spread of flame, leaving the fire source, can quickly stop burning.

Flame-retardant finishing has three ways:

(1) burnout method: the flame retardant combines with cellulose fiber or chemical fiber with ionic bond or covalent bond, so that it does not dissolve in the fiber and obtains the durability flame retardant effect.

(2) original liquid method: the flame retardant agent is directly added to the spinning solution.

(3) copolymerization: the flame retardant is added to the polymer chain segment to make the fabric with washing resistance, bleaching resistance, sweat resistance and other qualified fastness, without causing absorption by the skin. Printing and dyeing factory mainly adopts the first method.