Upgradation of Waste Dyed Fiber Through Production of Upcycled Rotor‐Spun Yarn: Enhancing Sustainability in Textiles

ABSTRACT Significant quantities of fiber waste are generated across the textile production chain, a substantial portion of which—particularly the short fibers arising from fabric finishing processes such as sueding—is typically incinerated due to its inadequate length and incompatibility with conventional blow‐room processing. This study demonstrates the upcycling potential of recycled dyed fiber waste (RDFW) from the sueding process by converting it into high‐value rotor‐spun yarn. The RDFW in tuft form were directly introduced into the carding machine, circumventing the blow‐room stage that conventionally rejects short fibers. Specifically, 14Ne and 16Ne open‐end rotor yarns were produced by incorporating 5% and 10% RDFW, and their uniformity and tensile properties were systematically evaluated and compared with yarns manufactured from carding machine waste (CMW) and post‐consumer waste fibers (PCMW). The results reveal that the developed yarns exhibited superior evenness, with notably lower CVm% and imperfection index (IPI) compared to those produced from CMW and PCMW. Furthermore, the findings demonstrate that 14Ne rotor‐spun yarn incorporating up to 10% RDFW can effectively serve as a high‐quality substitute for rotor yarns made from CMW and PCMW. A single jersey knitted fabric was produced from the developed yarn to assess its esthetic appeal and potential end‐use applications. The pre‐dyed nature of the RDFW eliminates the need for additional dyeing, thereby enabling the production of inherently colored or mélange yarns while significantly reducing water, energy, and chemical consumption. Furthermore, repurposing RDFW can substantially mitigate the environmental burden associated with virgin fiber production, offering potential savings of 6000–22,000 L of water and approximately 1.2 kg of CO 2 per kilogram of fiber. Overall, the upcycling of RDFW emerges as a practical and viable strategy to valorize textile finishing waste and advance circular economy principles in sustainable textile manufacturing.