Pre-processing process editing voice

1. Singeing

Whether the flannel needs singeing should be decided according to the fabric structure and processing requirements. Under normal circumstances, flannel does not need singeing, such as printed single-sided fleece. If the printed pattern is printed on the fleece side, singeing loses its meaning. However, printed single-sided velvet, such as the printed pattern, is printed on the non-velvet side, and the non-velvet side can be singed. Gas singeing is better, but the flame size and speed should be controlled to achieve the singeing effect without affecting the quality of the singeing.

2. Desizing (cooking)

If the slurry on the flannel is not cleaned, the fibers will be adhered to the slurry, which will affect the fuzzing effect. Therefore, the flannel must not only be desizing, but also require a good desizing effect. At the same time, it is required to maintain a certain amount of wax on the fabric before flocking, because the presence of wax is conducive to the insertion and detachment of the raising needles and improving the raising effect. In order to maintain the waxy quality of the fabric I: the flannel fabric can be scoured without scouring, but without scouring, the impurities on the grey fabric cannot be removed, which will affect the appearance of the finished product. For example, from the perspective of improving the desizing effect, enzyme desizing effect is better for starch slurry, but enzyme desizing cannot remove impurities, so it is not suitable. Practice has proved that using a higher concentration of lye to desizing can improve the desizing effect, and at the same time, it can also achieve the light scouring effect of removing some impurities, so that the capillary effect can reach 6-8cm/30min.

Generally, two-step caustic soda stacking is used, which is more conducive to puffing cotton seed hulls and improving the quality of flannel semi-products. The remaining lye can be used for the second alkali rolling.

Desizing and scouring methods are nothing more than rope scouring and bleaching and width scouring and bleaching. The selection should be based on the characteristics of the fabric and the processing requirements. Usually, except for the tighter and thicker flannel, the general looser fleece fabric To choose rope 1: better art. After desizing (scouring), the grease removal rate on the flannel is generally about 45%.

3. Bleaching

Flannel bleaching generally uses sodium hypochlorite bleaching process. Because the flannel is lightly scoured or not scoured, in addition to strengthening the desizing process, the bleaching process should also be strengthened. Only in this way can the quality of the flannel scouring and bleaching semi-products be guaranteed. Flannel bleaching requires not only to ensure the strength of the fabric, but also to achieve the required whiteness standard, and the cloth surface should be free of cotton seed hulls.

4. Mercerizing

After the fabric is mercerized, the yarn twist increases, the fiber swells, and the warp and weft density changes accordingly. At the same time, mercerizing can also remove some natural oil and wax on the fabric, thereby increasing the difficulty of fluffing, so the flannel generally does not require mercerizing. of.

But mercerizing can reduce the shrinkage rate, increase the vividness of the color, and improve the printing effect of the calico. Therefore, the question of whether the flannel should be mercerized is still worth studying.

5. Fleece

Bleached velvet and dyed velvet usually need to be padded with softeners separately before raising, and bleached velvet needs to be appropriately whitened with whitening agent and paint blue liquid, and then raised; printed velvet can generally be directly raised after bleaching and drying. velvet.

(1) Raising equipment. The raising is carried out on the drawing machine.

The brushing machine is composed of the circumference of the large roller of the main shaft, two small rollers wrapped with 36 steel wire clothings. These small rollers are divided into 18 pairs. The needle points of each pair of pulling teeth point opposite and rotate in the same direction. The needle point points in the same direction as the cloth travel direction, which is called a clock roller. It is customarily called push teeth; the needle point points opposite to the cloth travel direction. The counter-needle roller is customarily called the pull tooth. They revolve in the positive direction of the big roller, and rotate in the reverse direction of the big roller. Under normal circumstances, the counter-needle roller is napped, the needle tip is inserted into the weft, and the cilia is pulled out like a hoe turning the ground; the clockwise roller is used to pull out the cilia, but when the circumferential speed of the clockwise roller is less than that of the large roller It also plays the role of pulling hair when the circumferential speed of the cylinder is reached. The number of raising passes is determined by the structure of the fabric, the twist of the yarn count, the condition of scouring and bleaching, and the speed ratio of the clockwise and counterclockwise rollers of the drawing machine. Generally, it is pulled 6 to 8 times on the raising machine.

(2) "Zero point" raising theory. The "zero point" raising theory of raising has certain guiding significance for discussing the size of raising power and production practice. The so-called "zero point" raising means that the fabric does not come out after passing through the drawing machine. Using this method to find the "zero point" approximately, the size of the raising force can be controlled. Generally speaking, the raising force is controlled by adjusting the rotation speed of the clockwise and counter-clockwise rollers. According to the needs, the speed ratio can be adjusted by adjusting the speed change device to carry out the raising. The amount of raising is adjusted by the running speed of the fabric. The speed of the drawing machine is fast, and the number of times the needle tip contacts the fabric is less, and the amount of raising is less. On the contrary, the amount of raising is increased.

(3) Factors that affect the raising effect. The padding softener before the pile is conducive to raising the pile. The commonly used softeners are actually emulsifiers, such as paraffin wax, stearic acid, Akrabang A, softener 101 and soap, etc. Among them, softener 101 is more effective. The amount of softener 101 is 10～209/L, the temperature is 60～65"12, and the temperature should not exceed 80°C for a long time to avoid wax precipitation. The prepared padding liquid should be white emulsion, if it is turmeric and sticky. It means that the emulsification is not complete, and it is easy to cause stains on the padding fabric.

②The tension of the fabric during raising will affect the raising effect, because the resultant force of the tension is vertically distributed at the needle tip of the raising. The tension is large, the vertical pressure of the fabric on the needle 1 tip is also large, the resistance of the needle roller is large, the belt slip is also large, the pile power is small, the pile is shorter, and it is suitable for thin and compact chemical fiber fabrics that are easy to stretch. The tension is small, the raising force is large and uneven, the fabric will jump on the needle roller, and even cause the weft yarn to move, and the pile surface is like waves and is very uneven. Therefore, the tension control should be moderate during raising. The method of controlling the tension of the fabric in the drawing machine E is mainly controlled by the tensioning device of the cloth feed roller and the cloth exit roller, and adjust the tension appropriately.

③The moisture content of the fabric before raising and the temperature of the cloth body also have an effect on raising. Heated fabrics are easier to raise than cold fabrics. When the moisture content is 5% to 6%, it can eliminate static electricity and facilitate raising.

(4) Raising operations and requirements. The raising operation is also very important for the maintenance of the needle roller. When raising the needle roller when it encounters serious cloth sucking phenomenon, the cloth at the cloth entering place jumps sharply, the cloth is pulled at the cloth outlet, and the fabric fluff can not rise again, the raising should be stopped, and the fabric should be filled with new softener 10l. Fleece again, otherwise it will damage the needle cloth and damage the fabric. When raising the pile, it is necessary to strictly prevent the fabric from breaking. Because the broken fabric is wound on the counter-needle roller, not only the fabric is completely torn at this time, but the needle roller is also seriously injured or even scrapped. It should also be noted that the fabric should be moved left and right frequently during operation to ensure the uniformity of the sharpness of the needle points and the quality of the fabric. In addition, the needle point of the new needle roller is too sharp and needs to be sharpened before use. Generally, when the napping roller is used for about half a year, the needle point will become dull and sharpened.

In the long-term practice of napping, people have accumulated a lot of experience, such as stenting before napping to facilitate napping, smoothing operations in each napping, and mastering multiple light pulls during napping.

The pile requires short, dense and uniform piles. More importantly, the foot should be careful not to pile excessively, otherwise it will seriously affect the strength of the fabric. Generally, samples should be taken to test the strength when the pile is close to the standard. The weft strength after the pile should be at least 177N( 18kgf) above, otherwise it will affect the use fastness.

In long-term practice, people have summarized the "three attendance" system of attendance inspection, frequent investigation, and frequent contact on the raising operation method, which has a good effect on improving and ensuring the raising of the raising doubt.

6. Wash velvet

After the fabric has been raised, the surface will have a layer of fluffy fluff, the fabric feels very soft, and some short fluffs that are pulled off during the raising process are attached to the surface of the flannelette. These short fluffs must be removed, otherwise it will be printed during printing. Causes defects such as dragging color, dragging paste, and intarsia tube. For printing after washing, usually 8～129/L acorn powder or starch slurry is used for sizing.