A novel low add

A novel low add-on dyeing process of cotton fabric with C.I. Reactive Black 5 has been implemented successfully with the assistance of dye-jet ejector units to produce precise wet pick-up ranging from 20% to 50%. The steaming process of the low add-on technology was investigated through evaluating the effects of relative humidity, steaming temperature, steaming time and water ratio on the surface temperature of the wet fabric and their influence on the dye properties, as well as the effect of the wet pick-up on dye properties. The optimal dyeing process was also conducted, including build-up properties and the concentrations of the alkaline agent and the electrolyte via the evaluation of the color strength (K/S value) and dye fixation rate. A comparison was made between the novel low add-on dyeing process and conventional dyeing process by assessing the dye properties, color shade and color levelness. The results indicated that the fabric dyed with the low add-on process had excellent washing fastness, rubbing fastness, a similar color shade and superior levelness in comparison with conventional one-bath pad-steam dyeing