The Reactions of Cold‐dyeing Procion Dyes with Cellulose

The historical development of reactive dyes for cellulose and wool is reviewed briefly. The reactions of dichloro‐s‐triazinyl dyes with water, cellulose‐model compounds and with the primary and secondary hydroxyl groups of cellulose are discussed and a scheme for describing the fixation of these dyes under mild and severe conditions of alkalinity and temperature is presented. Paper chromatography, colour reactions in presence of a pyridine—caustic soda mixture, and cuprammonium solubility have helped to provide the evidence on which this scheme is based.