Pretreatment auxiliaries for dyeing and printing refer to chemical auxiliaries used before dyeing or printing textiles to improve fiber properties, remove impurities, and enhance the effects of subsequent processing. Their main functions include assisting in processes such as desizing, scouring, bleaching, and mercerizing, ensuring that the fabric possesses good wettability, whiteness, cleanliness, and uniformity, providing ideal base conditions for subsequent dyeing or printing. These auxiliaries are widely used in the pretreatment stage of cotton, linen, chemical fibers, and their blends, and are a key step in improving the quality of dyeing and printing.
In practical applications, there are many types of pretreatment auxiliaries for dyeing and printing, commonly including penetrants, scouring agents, chelating dispersants, hydrogen peroxide stabilizers, and alkali agents. Penetrants can significantly reduce the surface tension of liquids, promoting rapid and uniform penetration of the treatment solution into the fiber interior; scouring agents effectively remove natural impurities in fibers such as waxes, pectin, and cottonseed hulls; chelating dispersants, by binding with metal ions, prevent hard water from affecting the treatment effect and avoid redeposition of impurities; hydrogen peroxide stabilizers ensure a stable and controllable oxidation reaction during bleaching, preventing fiber damage.
