As we all know, the raw wool contains a lot of sediment, grass, minerals, sand, urine alkali and other impurities and lanolin. Therefore, in the wool processing process, the second process is the wool washing. The purpose of washing is to remove impurities such as sediment, to remove lanolin, and to whiten the whiteness of wool. Therefore, the choice of detergent is particularly important. Washing is not clean will affect wool, spinning, weaving and dyeing processes. These impurities are removed by washing and loose white wool fibers are obtained for textile. Wool cleaning agent can be divided into neutral wool washing agent, alkaline wool washing agent and acid wool washing agent according to acid and alkali degree.
Classification of wool cleaning agents
1. Neutral hair detergent
Neutral scouring agents include anionic surfactants and non-ionic surfactants.
Among anionic surfactants, sodium alkyl sulfonate or sodium p-methoxyfatty amine benzenesulfonate has the best washing effect. In order to improve the washing effect, sodium oxide, sodium sulfate sodium polymetaphosphate and other synergists can also be added.
The neutral detergent of non-ionic surfactant has good detergency, and this kind of detergent is not absorbed by wool, and the amount of detergent is less. At present, nonylphenol polyoxyethylene ether and other nonionic surfactants are used most.
2. Alkaline hair detergent
When wool is washed in a lotion with PH value of 8.5~9.5, its spinnability, antistatic property and water absorption are more favorable. Common alkaline washing agents are sodium alkyl benzene sulfonate, cleaning agent R5, anionic surfactants plus soda ash and so on. Because wool is sensitive to alkali, it is necessary to carefully arrange and master the pH value, lotion temperature and drying temperature when washing wool to prevent damage to the fiber. According to the different agents used, it is divided into soap and alkali washing, light alkali washing and ammonium alkali washing.
3. Acid hair detergent
The method of acid wool washing can remove the alkaline effect of alkaline soil impurities, protect the original elasticity and strength of wool fiber, and reduce the degree of shrinkage. The surfactant added to the acid solution can make the lotion quickly spread to the inside of the fiber and improve the wetting emulsification effect. And can make the fiber swelling, improve the uniformity of the opening Angle of the scale layer, so that the wool is easy to wash, good luster. Nonionic surfactants such as lauryl alcohol polyoxyethylene ether and anionic surfactants such as sodium alkyl sulfonate and sodium alkyl benzene sulfonate can be used as acid wool washing agents.