Real-time dyebath monitoring of reactive dyeing on cationized cotton for levelness control: part 2—effects of leveling agents and dye dosing

Abstract

Cationization of cotton brings advantages in the reactive dyeing process, such as eliminating the use of electrolytes and increasing color yield. However, high dye strike rates caused by the electronic attractions between anionic dyes and cationized cotton may result in poor levelness of dyeing, especially for light shades. For some monochloritriazine–monochloritriazine homobifunctional reactive dyes, lowering dyeing temperature and controlling the addition of electrolytes can effectively control the dye strike rate and improve the levelness of dyed cationized cotton. However, for other reactive dyes, the use of effective leveling agents is necessary. In this study, a variety of anionic, cationic, and amphoteric leveling agents were applied to control the dye exhaustion process of three monochloritriazine–vinylsulphone heterobifunctional reactive dyes on the cotton fabric cationized using 3-chloro-2-hydroxypropyl trimethylammonium chloride. The leveling effect of adding dyes in portions was also evaluated and it was used in combination with leveling agents to further improve the levelness of dyeing.