Enhancing the Sustainability of Kenaf-Cotton Blends: The Role of Pre-treatment in Optimized Solubilized Vat Dyeing

The use of non-conventional natural fibers in textiles requires appropriate processing to achieve acceptable dyeing performance. Kenaf fiber offers environmental benefits but presents dyeing challenges due to its complex fiber structure. This study aims to analyze the impact of pre-treatment on the dyeing characteristics of solubilized vat dyes applied to handloom-woven kenaf and handspun cotton fabrics. Four pre-treatment conditions were examined: untreated, scouring, bleaching, and combined scouring–bleaching. The fabrics were dyed under controlled conditions and evaluated through fabric characterization, visual color assessment, and color fastness tests to washing, rubbing, and perspiration. The results show that pre-treatment has a significant effect on dye uptake, color uniformity, and durability. The combined scouring–bleaching treatment produces the most uniform and intense color and achieves excellent color fastness performance. These improvements are associated with enhanced fiber cleanliness and improved accessibility of the fiber structure for dye fixation. This study demonstrates that pre-treatment is a key factor in optimizing the dyeing performance of kenaf–cotton blended fabrics and provides practical insights for the development of sustainable and value-added textile products.