Fiber and Fabric‐Integrated Tracing Technologies for Textile Sorting and Recycling

Over 85% of textiles currently end up in landfills, despite a recent study indicating 74% of low-value, post-consumer textiles, nearly 500,000 tons per year in Europe alone, are readily available for fiber-to-fiber recycling. A key challenge in implementing fiber-to-fiber recycling is feedstock ambiguity; even advanced near infrared sorting systems face significant challenges in differentiating blended fiber fabrics at scale. Furthermore, an increasing emphasis on ethical fiber sourcing and the assurance that fabrics and garments are made with fair labor practices requires enhanced methods of tracing and validation. In the textile and apparel industry, product life cycle management is hampered in part by inaccurate, poorly readable, and detachable standard care labels. Integration of easily readable, cost-effective, and fully recyclable tracing technologies directly into the fiber or fabric could address multiple concurrent challenges across the entire textile supply chain currently inhibiting a transition to a functioning circular economy. In this manuscript, a critical systems-level analysis of the tracing and sorting challenges facing all textile life cycle stages (fiber/yarn/fabric/garment manufacturing, brand/retailer, consumer, sorting, and recycling) provides the foundation for comparing the techno-economic feasibility of emerging technologies that have been proposed for direct fiber, fabric, and garment tracing and sorting. This includes the current standard care label, quick response (QR) codes, and radio frequency identification (RFID) tags as well as emerging direct fiber marking techniques such as those using DNA, organic molecules, or rare earth fluorescent nanoparticles. These emerging fiber marking techniques are also compared to a recently developed fiber-based "barcode" that uses all-polymer photonic structures that can be manufactured at scale and with low-cost while remaining compatible with textile manufacturing processes and being made of recyclable materials. Finally, recommendations are provided for focusing the future technological development of integrated tracing methods as well as promoting cooperation across the textile industry and regulatory bodies.