Let's introduce some common washing processes of Tiansheng Chemical:
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Garment Wash
Generally, the water temperature is around 40 ° - 50 ° C, and the temperature may be higher sometimes according to the fabric and requirements. Add a certain amount of softener TS-688, and if necessary, add anti-dye TS-350. The process time varies from 5 to 30 minutes according to the requirements of the bulk goods. The actual operation is determined according to experience. Because this process is relatively simple and the single quantity is relatively large, it is relatively cheap.
2. Bio polishing
Use bio-polishing enzyme 0.5% - 2.0% (for the weight of clothes), temperature 45 ° C to 55 ° C, time 20 to 30 minutes, penetrant 0.5 g/L (can not be put in order to reduce costs), pH 4.5 to 5.5 (use 0.5 mL of 98HAc and 0.5 g of sodium acetate per liter to adjust the PH value), bath ratio 1:10-1:15. After finishing with biological polishing enzyme, the surface fuzz is almost invisible: it is not easy to produce fuzzing and pilling, and the hygroscopicity, drapability and hand feel of clothes have been significantly improved. The method of controlling the weight loss ratio of clothes from 3% to 5% is used to judge the polishing effect without excessive damage to the strength. However, after bio-polishing, some of the color and shade change greatly, which should be paid attention to in use.
3. Desizing
The purpose of desizing is to remove the size from the clothing, so as to facilitate the post-processing and have good production conditions. Because most denim uses starch or modified starch size, amylase can be used for desizing. Common desizing process formula (calculated per liter): enzymatic TS-231 1g to 2g, sodium carbonate 2 to 5g, penetrant TS-CE1 to 2g, glacial acetic acid 0.51.5mL, softener TS-688 0-2g. Process conditions: pH 6.0 to 7.0, bath ratio 1:10 or 1:15, temperature 50°C to 60°C, time 30min. Because there is usually residual alkali on denim, acetic acid is added to the desizing bath, and the pH value is adjusted from 6.0 to 7.0, so that the amylase can play its best role. Softener is added to produce streaks in the desizing process of some heavy denim. Of course, the cost of using this method is too high, so when there is no special requirement for desizing, only pumice stone and a small amount of anti back staining agent TS-350 can be added. The temperature is relatively high, and the time is 10 to 20 minutes. The actual operation depends on the technician's experience.
4. Enzyme/ Stone wash
Cellulase is fermented by a single fungus. It can hydrolyze the surface of cellulose and partially produce water-soluble products such as short-chain polysaccharides and glucose. Because the dyeing and finishing of denim is only on the surface of the fiber, cellulase removes the dye attached to the surface of the fiber while partially hydrolyzing the surface of the fiber. According to the requirements of pH value of water during stone washing, cellulase is divided into acidic cellulase and neutral cellulase. The optimal pH value of acid cellulase is 4.5-5.5 (sensitive to pH value and low price). The optimal pH value of neutral cellulase is 68 (relatively stable for pH value and high price). Process conditions: cellulase 0.5% to 1.5% (for the weight of fabric), pH value 4.5 to 5.5 (acid enzyme), 6.0 to 8.0 (neutral enzyme), treatment time 30 to 60 minutes, temperature 30 ° C to 50 ° C, not more than 60 ° C, because biological enzyme will be killed if it exceeds 60 ° C, so if the time is too long in the process, when the water temperature becomes low, the cellulase can only be drained and re-discharged without steam heating, The pumice dosage is 0 to 500g/kg (depending on the degree of aging), and the bath ratio is 1:10 or 1:15. Using cellulase to wash the stone mill can greatly reduce the amount of pumice (only about 25% of the original amount of pumice stone), even without pumice stone. At the same time, it can increase the washing capacity of the washing machine and reduce environmental pollution. Due to the reduction of pumice grinding on the fabric, the fabric feel obviously soft, natural and bright after washing. During the washing process of the stone mill, the indigo dye that falls off in the water bath has obvious back-stained phenomenon when the pH is below 6.0, which leads to the blue color of the denim seam inlay and inner pocket material, and the blue-white contrast style after finishing is reduced. When the pH in the water bath is above 7.0, the phenomenon of back staining will be significantly reduced. Therefore, neutral cellulase is suitable for high-grade clothing finishing. Acidic cellulase can be used in low-grade and various stone mill rinsing processes. The Japanese process is to turn on steam to over 60 °C after fermenting and washing to kill the biological enzyme completely before washing
5.Bleaching
Three common methods of bleaching:
1. Oxygen bleaching (water element) uses hydrogen peroxide and caustic soda to destroy the structure of the dye under high temperature to achieve leg color effect. After washing, it needs not be neutralized after three times of water. It is mainly used to wash black cattle, that is, black jeans. However, Chinese washing technicians generally prefer to use potassium permanganate to bleach, which is much more technically difficult. However, it saves money and time, and the requirements for washing technicians are too high.
2. Sodium hypochlorite is used for chlorine bleaching (secondary ya). If less soda is added to the elastic fabric, wash it and neutralize it with baking soda. This is the simplest and most commonly used bleaching method.
3. Salt free bleaching (salt free bleaching) is a very common method in Japan. It is relatively difficult to bleach the blue denim fabric at a high temperature of 80 to 90 degrees using salt free indigo bleaching agent and caustic soda. Restore the original packaging after neutralization. This method is generally not used unless there are special requirements.
