Dyeing of advanced denim fabrics (blend of cotton/bicomponent polyester filaments) using different processes and...

Denim clothes are the must-have items of clothing around the world. This kind of fabrics is evolving with the increasing consumer demand in order to keep its place as a versatile article. In this context, this paper contributes to the development and dyeing of a new blend fabric made of cotton fibers and bicomponent polyester filaments (PET/PTT). A comparative study between the mechanical and thermal properties of this fabric and conventional fabrics has confirmed the great interest to use bicomponent (PET/PTT) filaments in the manufacture of denim fabrics; these bicomponent filaments allow to give to wearer the desired elasticity and comfort. For dyeing (cotton/bicomponent polyester filaments) blend fabric, three different processes, using reactive and disperse dyes, were tested and analyzed. These dyeing processes are: two-baths/two-phases, one-bath/two-phases, and one-bath/one-phase processes. In addition, in order to obtain uniform shades between cotton fibers dyed with reactive dyes and bicomponent polyester filaments dyed with disperse dyes, an ant colony algorithm was elaborated to predict the optimal dye recipes. By observing obtained results, the developed algorithm is very effective; it allows to find the combination of reactive dyes necessary to achieve the same shade obtained by the disperse dyes with very small color differences between the two components and without having to make corrections mainly for the one-bath/two-phases process. Indeed, dyeing using the two processes (two baths/two phases and one bath/two phases) presents the best values of color yield (K/S) with almost similar results (ΔE_CMC(2:1) <  < 1). For the one-bath/one-phase process, it presents less significant results; We can observe ΔE_CMC(2:1) greater than 1 in certain shades. This is due to the strongly pH value (basic pH of 11) of reactive dyeing.