Symposium on “Recent Advances in the Colouring of Man‐made Fibres”

Abstract

Successful results in dyeing depend on a series of simultaneous equilibria. The formation of micelles by non‐ionic levelling agents has been demonstrated spectroscopically and the micellar size determined. The equilibrium conditions in the formation of complexes between dyes and levelling‐agent micelles have been studied. These conditions are intimately related to the equilibrium between dye and fibre. The latter equilibrium has been investigated with dyeings on polyamides. Study of the simultaneous equilibria dye‐fibre and dye‐levelling agent gives a clear picture of the nature of the retarding and levelling action of textile auxiliaries. The equilibrium between auxiliary and dye decreases the association of the latter. Results obtained in previous diffusion studies, however, have been interpreted as indicating increased association of dyes on addition of levelling agents. These results have been re‐examined, and shown to be in accordance with the theories developed in the present paper.