REACTIVE DYE SELECTION AND PROCESS-DEVELOPMENT FOR EXHAUST DYEING OF CELLULOSE

In dyehouses processing cellulosic fibers with reactive dyes, much pro gress has been made in the quest for zero defect production by the int roduction of controlled coloration techniques which support level dyei ng performance.(1) There is however, still room for further improvemen t, especially in the area of shade reproducibility. Shade reproducibil ity can be significantly improved by considering the compatibility of the dyeing profiles of the dyes selected. By studying the properties o f dyes during the primary and secondary exhaustion phases of the proce ss and their reactivity, the measures and levels of performance requir ed to achieve right-first-time production can be defined. The Reactive Dye Compatibility Matrix (RCM) can be used to define the optimum dyei ng profile for exhaust dyeing with reactive dyes, quantify dye migrati on properties, the degree of process control required to achieve shade reproducibility and level dyeing performance, and an index of dye rea ctivity. Understanding the RCM will allow dyes with similar properties to be identified and used in combination to support right-first-time production, It can predict the performance of dyes on the most recentl y introduced dyeing machinery and in new application techniques which have been designed to minimize the impact of reactive dye systems on t he environment. It can also be used as a diagnostic tool when optimizi ng application techniques.