Institute for Color Science and Technology (ICST) Progress in Color, Colorants and Coatings 2008-2134 19 2 2026 05 01 Sustainable Dyeing of Silk Fabric with Mango Leaf Extract: Comparative Assessment of Natural and Metallic Mordants on Colorimetric and Fastness Properties 231 245 82138 10.30509/pccc.2025.167632.1433 EN M. R. Hossen Department of Wet Processing Engineering, Shahid Abdur Rab Serniabat Textile Engineering College, P.O. Box: 8200, Barishal, Bangladesh Senior Executive, Apex Holdings Limited, P.O. Box: 1751, Chandra, Kaliakoir, Gazipur, Bangladesh S. Sayam Department of Fabric Engineering, Barishal Textile Engineering College, P.O. Box: 8200, Barishal, Bangladesh S. Akter Department of Geography and Environmental Studies, National University Bangladesh, Gazipur, P.O. Box: 1704, Dhaka, Bangladesh Journal Article 2025 08 15 This study investigates the sustainable dyeing of silk fabric with mango leaf extract and compares the effects of natural and metallic mordants on colorimetric and fastness properties. Silk fabric was degummed, bleached, and dyed using mango leaf extract under pre-, simultaneous, and post-mordanting techniques with bio-mordants (Aloe vera, lemon, myrobalan, mango bark, eucalyptus) and metallic salts (alum, copper sulfate, ferrous sulfate). Color analysis showed that simultaneous mordanting with mango bark achieved the highest color strength among natural mordants (K/S = 16.25, 127 %), while ferrous sulfate produced the deepest shade under post-mordanting (K/S = 14.93, 117 %). Aloe vera and lemon generated lighter shades, whereas tannin-rich mordants significantly reduced reflectance and improved absorption at λmax, confirming their strong affinity for dyes. Fastness performance was satisfactory across all samples, with washing and rubbing ratings ranging from 4 to 5 on the ISO grey scale. Results demonstrate that natural mordants can provide color performance comparable to that of metallic salts while reducing environmental hazards. The findings highlight the potential of natural mordants and mango leaf extract as eco-friendly alternatives for protein-based textile dyeing; however, further research is necessary to enhance shade reproducibility, extraction efficiency, and scalability for industrial applications. https://pccc.icrc.ac.ir/article_82138_af3fd735f9ffc21a63f5da683f66ffbb.pdf