Optimized single-bath dyeing of bio-based nylon 56/cotton blends with vat dyes: Mechanistic insights and process enhancements.

Nylon 56/cotton (N/C) blended fabrics have excellent durability and can cater to various clothing needs. However, the quality and value of textile garments are significantly influenced by the dyeing process. Due to variations in the structure and characteristics of nylon 56 and cotton fibers in blended fabrics, achieving consistent coloration is challenging, resulting in noticeable color discrepancies. To tackle these issues, this study focused on dyeing nylon 56/cotton blended fabrics in a single bath using vat dyes. The three primary colors of the vat dyes were selected to be suitable for these fabrics. Subsequently, the study explored the impact of different factors on color consistency and optimized the dyeing process conditions using response surface methodology. The findings revealed that fabrics dyed using the optimized process exhibited vibrant colors, uniformity, and excellent colorfastness to soaping and rubbing, surpassing standard requirements. Furthermore, the study delved into the dyeing mechanism of nylon 56/cotton blended fabrics, analyzing the kinetic and thermodynamic properties of dye adsorption on fibers. This analysis aims to provide a theoretical foundation for developing a rational dyeing process and offer guidance for practical production.