Carboxymethyl cellulose (CMC) plays an important role in washing powder, mainly to improve the washing effect and protect clothes. Specifically, the role of carboxymethyl cellulose in washing powder can be divided into the following aspects:

1. Preventing redeposition
During the washing process, the dirt is stripped from the clothing fibers by the detergent, but these dirt may be deposited on the clothes again, which greatly reduces the washing effect. Carboxymethyl cellulose can form a protective film to wrap these dirt particles and prevent them from reattaching to the clothing fibers. This feature greatly improves the cleaning ability of the detergent, making the clothes cleaner after washing.

2. Provide thickening effect
Carboxymethyl cellulose has good water solubility and can form a high viscosity solution in water. This thickening effect helps to improve the stability and dispersibility of the washing powder, so that the washing powder can be more evenly distributed in the water, thereby improving its washing effect. In addition, the thickening effect can also increase the adhesion of the washing powder, making it easier to adhere to the surface of the clothes and improve the washing efficiency.

3. Protect fibers
During the washing process, clothing fibers may be damaged by the dual effects of chemical components in detergents and mechanical agitation. Carboxymethyl cellulose can form a protective film on the fiber surface, reducing the erosion of chemical components on the fiber, and also slowing down the wear of mechanical agitation on the fiber. This protective effect is especially important for fine and delicate clothing fibers (such as silk, wool, etc.).

4. Improve foam performance
Carboxymethyl cellulose has a certain effect on the stability of foam. An appropriate amount of carboxymethyl cellulose can adjust the foam performance of washing powder, so that it can produce an appropriate amount of foam, which can fully exert the washing effect without affecting the rinsing effect due to excessive foam. At the same time, stable foam can also enhance the lubrication effect of washing powder during the washing process and reduce the friction between clothing and the wall of the washing machine barrel.

5. Provide lubrication
During the washing process, friction between clothing and the washing machine is inevitable. Carboxymethyl cellulose can form a slippery colloidal solution in water. This solution forms a lubricating film on the surface of clothing, reducing friction, thereby protecting clothing fibers and extending the service life of clothing.

6. Improve solubility
Carboxymethyl cellulose has good solubility in water, which allows washing powder to dissolve more quickly in water and exert its washing effect. At the same time, carboxymethyl cellulose can also help other insoluble ingredients (such as certain detergent aids) to disperse more evenly in water, improving the overall performance of detergents.

7. Increase the stability of detergents
Certain active ingredients in washing powder (such as enzymes, bleaching agents, etc.) may degrade during storage, resulting in a decrease in washing effect. Carboxymethyl cellulose can stabilize these active ingredients and extend the shelf life of washing powder through its colloid protection.

Carboxymethyl cellulose plays multiple roles in washing powder. It not only improves the washing effect and protects clothing fibers, but also improves the physical properties and stability of washing powder. Therefore, carboxymethyl cellulose, as an important additive, is widely used in various washing products.