Environ Sci Pollut Res Int. 2025 Dec 13. doi: 10.1007/s11356-025-37294-3. Online ahead of print.
ABSTRACT
This study evaluates the effectiveness of metal-organic acid mordanting systems as sustainable alternatives to high-concentration metallic mordants in natural dyeing of wool yarns using Rubia tinctorum (madder) and Reseda luteola (weld). A total of 46 treatments involving single metals, organic acids, and their binary combinations were applied, and the dyed yarns were assessed for colorimetric parameters (K/S), ultraviolet protection factor (UPF), and antioxidant activity. The results demonstrated that binary mordant systems, especially those combining copper and iron salts with citric or tartaric acid, significantly enhanced color strength (K/S up to 12.05), UV protection (UPF > 90), and radical scavenging activity (up to 96.10%), often surpassing the performance of conventional 5% metal mordants. Non-parametric Kruskal-Wallis tests showed statistically significant improvements (p < 0.05) for weld-dyed samples in all functional categories, while correlation matrices revealed strong associations between K/S, UPF, and antioxidant values in weld, but weaker links in madder. These findings confirm that binary metal-acid mordanting systems can effectively reduce metallic load without compromising or even enhancing dye performance, photoprotection, and bioactivity contributing to both textile sustainability and functional innovation.
PMID:41389125 | DOI:10.1007/s11356-025-37294-3
