Analysis of the influence of post-processing parameters on the curling phenomenon of knitted fabrics using pixel images

Curling is a common phenomenon in knitted fabrics, which can affect production efficiency and quality, and edge curling is greatly affected by dyeing and finishing processes. This article proposes a pixel-analysis-based testing method to quantify edge curling problems and reveal the relationship between curling and dyeing parameters. This study investigated three different colors (white, blue, and black) on the same fabric sample. For each color, three finishing methods were used: no softener, adding softener, and high-temperature setting after adding softener. The results showed that the rolled edges of the fabric were severe, and even without the addition of softener, the rolled edges of all three colors of fabrics were improved significantly after dyeing. The rolled edges of white fabrics are the lightest, whereas the curled edges of blue and black fabrics gradually increase. Softener effectively improves the problem of edge curling by reducing the friction coefficient between yarns, decreasing internal stress in fabrics, and lowering the bending stiffness of yarns. The mechanical effects of high-temperature setting and pressure flatten the fuzz, which can reduce the friction coefficient and bending stiffness of the yarn, and also help improve edge curling.