An Insight into the Diffusion of Direct Dyes into Cellulosic Materials: Effect of Fabric Characteristics, Dye Structure, and Bath Composition.

The comprehension of capillarity phenomenon is important in chemical, printing, and textile dyeing. The current paper provides an insight into the diffusion of direct dyes into cellulosic materials with regard to the change of fabric characteristics, dye structure, and bath composition. First, an experimental device was developed and series of experiments were carried out using cotton as textile fabric model and direct dyes (Direct Orange 39, Direct Red 79, and Direct Red 80) as wicking liquids. Data were analyzed based on the evolution of diffusion rate [D (cm2/s)] versus C/C0. Results exhibited that the capillary ascension of dyes depends on weft count, weave structure, yarn type, angle contact, wet agent, dye structure, and dye concentration. The D (cm2/s) values were much higher than for twisted yarn. The tortuosity lowered the diffusion of the dye along with fabrics. The rate of water transport increased with weft count and it became more important when the structure of fabric is more tightened. Both inter-yarn space and vertical position of the fabric limited the ascension of the liquid. In brief, along this study, we demonstrated that the proposed apparatus could provide a potential evaluation of wicking phenomenon along with textile materials. [ABSTRACT FROM AUTHOR]