Uses: 5-Sulfoisophthalic acid monosodium salt is usually used to prepare a variety of environment-friendly water-based coatings or waterborne polyurethane resins, can also be used in inks, magnetic tape, and polyester and nylon fiber, as well as make PET bottle inks own better printability, excellent interlayer adhesion of tape , improve the dyeability and light resistance of polyester and nylon fibers, can take part in the esterification reaction of polyester as the substitute of Dimethyl-5-sulfoisophthalate sodium salt, can improve the drying property of products. Can also be used in medicine, pesticides, polyester, and other fields as a catalyst.