The Essential Role of pH Control in the Dyeing of Carpet Fibres

In the dyeing of nylon, wool, acrylic and even polyester fibres for carpets, control of the dyebath pH is essential for the attainment of level reproducible results. It is not uncommon, however, to find in practice that the means of controlling the pH is inadequate in terms of the particular chemicals chosen or in the concentrations employed. This arises because of an imprecise knowledge of the function of buffering or other pH-controlling agents, and the practice of a false economy in their use. This paper outlines these principles and indicates simple, economic and reliable means of pH control. The systems described relate to optimized dyeing methods, particularly those where dyeing behaviour is critically affected by dyebath pH