Modelling the properties of one‐step pigment‐dyed and finished polyester/cotton fabrics using response surface methodology

Dyeing of polyester/cotton blended fabrics with two different classes of dyes for polyester and cotton is a lengthy and expensive procedure owing to different fibre contents that need different auxiliaries, pH, and temperature conditions. The aim of this study was to investigate and model the properties of a combined pigment dyeing and hand‐building finishing system for polyester/cotton blended fabrics. The one‐step process was investigated using response surface methodology, taking concentrations of pigment, softener, and hand‐building finish as experimental variables. It was found that increase in hand‐building finish helps to improve colour fastness at higher pigment concentrations but results in deterioration in fabric tear strength. However, the decrease in tear strength can be minimised by increasing the softener concentration. For a 15 g l^?1 pigment concentration, optimum fabric tear strength, crease recovery angle, bending length, and dry and wet rubbing fastness properties were obtained using 60 g l^?1 of softener and 65 g l^?1 of hand‐building finish. The prediction equations developed in this study can be used to determine the required amounts of softener and hand‐building finish to achieve commercially acceptable results at different pigment concentrations.