Answer After the silk is sand washed, a soft layer of frosty white fluff (commonly known as grayscale) is produced on the surface of the fabric. In silk sand washing processing, it is divided into ...
Answer After the silk is sand washed, a soft layer of frosty white fluff (commonly known as grayscale) is produced on the surface of the fabric. In silk sand washing processing, it is divided into light, medium and heavy sand washing. Light sand washing requires the silk surface to be basically gray-free, maintain the original appearance, and have a soft and smooth hand feel. Heavy sand washing requires that the silk surface is not shiny, has a large gray scale, has a strong velvet feel, and has good wrinkle resilience; the indicators of medium sand washing are between light and heavy sand washing. During the dyeing and sand-washing processes of silk, it is very easy to produce “gray damage” defects. Because of the different states and physical and chemical effects during processing, the “gray damage” produced is also different. If the silk is not arranged in time during the sand washing process, the silk will be tangled or the amount of silk and water will be improperly controlled, resulting in “strips of dust” (commonly known as white strips); when using a centrifugal dehydrator to dehydrate, the brakes will be too fast, causing the dehydrator to “lumpy gray wounds” (commonly known as scratches) caused by being out of sync with silk Damage); “gray damage” (commonly known as strain) caused by the tension caused by the silk being clogged during vat dyeing and the silk being wrapped upside down on the oval guide roller during rope machine dyeing; the friction between the silk and the equipment during the processing. Friction, various “local bruises” caused by friction between pieces of silk. There are also heavy sand washing or repeated repairs, or the color light or rope dyeing temperature is too high and the time is too long, which makes the silk surface gray too much, like heavy sand washing, that is, “uniform gray damage” is formed.
The prevention method is as follows.
① During sand washing, master the amount of cloth and water; strictly control the silk processing time (including the time of soda ash sand washing and hot air and cold air time).
② Do not apply sudden braking when dehydrating.
③ When dyeing, attention should be paid to different equipment and different silk blanks, and the amount of silk should be controlled. The liquor ratio should not be too small to avoid excessive squeezing and friction of the blank silk and causing dust damage; the liquor ratio for rope dyeing should be With proper control, it is necessary to keep the gray silk in the dyeing bath Move freely without getting tangled; the water flow speed of the vat dyeing should match the speed of the silk blank to prevent clogging; when dyeing silk that does not require grayscale with a rope dyeing machine, the temperature should not be too high, otherwise it will easily cause the silk blank to be dyed Friction occurs due to boiling, causing ash wounds.
There are five methods of revision.
④Sand washing method. The principle of sand washing is used to produce uniform fluff on the silk surface to cover up “local gray damage”.
②Light oil wiping method. Dip a small amount of olive oil into the same piece of silk of the same color and rub it in your hands to allow the olive oil to fully penetrate. Use this silk to rub the whitened gray wound in one direction to make a small amount stick to the villi of the gray wound. Olive oil, the color becomes slightly darker, and it looks like there is no gray damage. When operating, be careful not to use too much oil, otherwise oil spots will appear. This method can only temporarily eliminate the dust damage. After washing, the dust damage will reappear.
③Dye application method. Dip the dye into the dyeing solution with a brush and carefully apply it to the gray wound to make the color of the gray wound consistent with other places. Then use an iron to flatten it to fix the color at high temperature.
④Enzyme treatment method. Utilizing the principle of enzyme refining, that is, protease can decompose proteins at appropriate temperatures and pH values, and the silk that needs to be repaired is treated with enzymes. The fine fluff that causes “uniform gray damage” on the silk surface is decomposed first, thereby eliminating the gray scale. However, the action of 2709 alkaline protease is slower, and due to the long wet treatment time, the color of the silk will fall off and the hue will change. You can use the “Silk Wash 2000” fast protease produced in Switzerland, which can eliminate grayscale in a short time and has good results.
⑤Singeing method. The principle of singeing is used to burn off the uniformly damaged fluff formed on the silk surface to eliminate the gray scale. However, this method is difficult to master. High-temperature singeing can easily cause the silk to deteriorate and turn yellow, so be extra careful.
The above ①②③ method is suitable for the repair of “local gray damage” such as “white strips” and “scratches”, and the ④⑤ method is suitable for the repair of “uniform gray damage”.
Extended reading: https://www. alltextile.cn/product/product-7-78.html
Extended reading: https://www.brandfabric.net/t-c-stretch-interweave-fabric/
Extended reading:https://www.alltextile.cn/product/product-94-270.html
Extended reading:https://www.china-fire-retardant.com/post/9375.html
Further reading: https://www.brandfabric.net/soft-shell-lamination-3-layer-fabric/
Extended reading: https://www.alltextile.cn/product/product-14-574.html