Fibrillation tendency of cellulosic fibers. VII. Combined effects of treatments with an alkali, crosslinking agent, and reactive dye

Lyocell woven fabrics were treated with crosslinking agents [1,3-dimethyl-4,5-dihydroxyethylene urea (X1) and 1,3-dimethylol-4,5-dihydroxyethylene urea (X2)], binders [polyacrylate (131), anionic polyacrylate (132), anionic polyurethane (B3), and aliphatic polyisocyanate (B4)], and polyfunctional reactive dyes in combination with alkali treatments. The effects of the treatment conditions, including the reagent types, the reagent concentrations, the process types (pretreatments or posttreatments with alkali), and the treatment combinations, on the fibrillation tendency and dyeing behavior in treated samples were investigated. Generally, the fibril number decreased with an increasing concentration of additives and decreased further with reactive dyeing. Fabrics treated with 45 g/L X1 (34 g/kg of fiber) or with 28 g/L X2 (21 g/kg of fiber) and dyed thereafter exhibited no fibrillation. Posttreatments with alkalis caused no changes in either the color shade or fibrillation tendency of crosslinked fabrics, although they enhanced the water retention capacity. The use of mixtures of binders 133 and B4 minimized the fibrillation, but the use of B4 led to changes in the color shade. (c) 2006 Wiley Periodicals, Inc.