What is the purpose of washing after reactive dyeing？

①Remove the alkaline agent remaining on the fabric to prevent "alkaline soaping" during high-temperature soaping, hydrolyzing and breaking the bonded and fixed dyes, forming new floating colors, reducing dyeing fastness and even causing light colors;

②Remove the unfixed dyes and hydrolyzed dyes remaining on the fabric to prevent the dye concentration in the soap solution from being too high during soaping, resulting in secondary staining and reducing the soaping effect.

Therefore, after dyeing, it must be washed with running cold water and then fully washed with hot water. Since the floating dyes on cotton fibers have higher solubility in hot water, the effect of hot washing to remove floating colors is better. Production practice has proved that good soaping effect can only be produced on the basis of good washing.