Nano Fixing Agent F6 is an auxiliary agent that can improve the color fastness of dyes on fabrics. The film-forming properties of the active Nano Fixing Agent F6 on the fabric improve its color fastness. In the high-temperature drying process of the dye-fixing agent treated fabric, the reactive groups on the dye-fixing agent molecules cross-link into macromolecules by themselves, forming a protective film with a certain strength on the surface of the fabric and fiber to coat the dye On the fiber, the dye is not easy to fall off. It can form insoluble colored substances with dyes on the fabric to improve the washing and perspiration fastness of the color, and sometimes it can also improve the light fastness. The bleaching and Nano Fixing Agent F6 can improve the washing fastness after fixing, and the color of the fixing working fluid is rarely faded, and it can effectively avoid the generation of light peeling and color change. The fabrics treated with the fixing agent have significantly improved soaping fastness and perspiration fastness, and the fixing agent does not contain formaldehyde, which conforms to environmental protection performance and does not affect the original style of the fabric. The aldehyde-free fixing agent has reactive groups in the molecule, which can be combined with dyes and fibers to improve the fixing effect. And it can improve the wet fastness and washing fastness of direct dyes, reactive dyes or printed materials, and will not affect the hand feel and re-wetting properties of the dyed products.