Abstract: The low refractive index of resin built-up agents can decrease the amount of light reflected on the surface of yarn and fabric. The paper explores the impact of various types of built-up agents, different finishing processes, and fabric specifications on the UV protection capability of fabric. The results show that the built-up agent can improve the UV protection performance without reducing the whiteness of the fabric. Different types of additives can enhance the UV protection of white fabrics to different extents.Among these, polyacrylate additives have better UV protection than silicon additives. Adding a builtup agent after desizing can improve the UV protection performance the most compared to adding a builtup agent after mercerizing and liquid ammonia finishing. Baking processing does not favorably improve the UV protection performance of deepening agents. Built-up agents have different effects on the UV protection performance of different fabrics, with twill showing better improvement than plain fabrics.

Key words: built-up agent; anti-ultraviolet; whiteness; reflect; refractive index