Cationic retarding agent is the most commonly used cationic dye dyeing retarding agent, the most is a cationic surfactant, such as surfactant (TAN) levelling agent 1227, 1631 surfactants (levelling agent Ⅳ state).
Cationic slow dyeing agent has affinity to acrylic fiber. For small molecules, and fiber smaller affinity cationic retarding agent, because of the high diffusion rate, the dyeing at first on fiber dyeing, such as cationic dye into the fibers, due to slow the affinity of dye and fiber is less than the affinity of dye and fiber, will be gradually replaced by dye, thus reduce the dyeing rate.
The amount of this type of slow dyeing agent should not be too large, or it will cause dyeing concentration in the late dyeing, but cause uneven dyeing. For cationic slow-dyeing agents with complex molecular structure and high affinity for fibers, they can compete with cationic dyes during dyeing, thus reducing the dyeing rate of cationic dyes. However, cationic slow-dyeing agents occupy a certain dyeing position in the fibers, thus reducing the dyeing percentage of cationic dyes. The higher the amount of cationic retarding agent, the more significant the retarding effect, but the dye will become lighter.
The amount of cationic retarder depends on the nature and concentration of the dye used. For dyes with small K value or light color, the amount of cationic retarder is higher, and for dyes with large K value or deep dark color, the amount of retarder is lower. Cationic slow-dyeing agent has saturation value on acrylic fiber and compatibility with cationic dyes. Cationic slow-dyeing agent with high affinity should be used for cationic dyes with high affinity. The amount of cationic retarding agent and cationic dye should not exceed the dyeing saturation value of the fiber.