Invariant kinetic parameters of dyeing

Based on isothermal exhaustion curves recorded at various temperatures, the possibility of describing numerically the uptake profile of a dyestuff has been investigated. Since the exhaustion process is a complex one, its kinetic parameters depend on the experimental conditions and cannot be used to characterise a group of curves. The alternative method proposed in this study is the use of invariant kinetic parameters for describing the exhaustion of a dyestuff in a dyeing system under various conditions. The concepts have been applied to the exhaustion of two reactive dyestuffs on cotton. The results show that all the isothermal exhaustion curves of a dyeing system can be described by a unique group of three parameters, ni, Ei and Ai.