The vat dye printing process is mainly used for the dyeing of cellulose fibers and their blended fabrics. It is not widely used in protein fibers; in synthetic fibers, it is generally only used for the dyeing of vinylon. The dyed vat of the vat dye is divided into two types, the light and the mercerized light, and more mercerized. The mercerizing of cotton cloth, according to different requirements, can be used after the first silk light dyeing or the first dyed silk. When dyeing light color, it is better to use the first dyeing and mercerizing process. Because of the greater affinity of the vat dye to the mercerized cotton fiber, such as first silking and dyeing, it is easy to produce strips and uneven dyeing. However, for certain vat dyes that are not resistant to mercerizing, such as the use of the first dyeing and mercerizing process, a more serious discoloration phenomenon will occur, which should be noted.