Integrated and surface optical anti-counterfeiting features in fibrous materials – A comprehensive review

Fibrous materials including textiles, apparels, banknotes, security documents, health care products, filters, construction, aerospace, packaging etc. form a part of our everyday life. Anti-counterfeiting involves implementation approaches to prevent the production of fake replicas of these goods, and facilitates increased brand protection, thereby improving consumer trust, and reducing economic losses. This article focuses on the recent research advancements on both integrated- and surface-level optical approaches that have emerged to combat counterfeiting in fibrous materials. The initial sections provide a comprehensive overview of the techniques used in preparing fibers for anti-counterfeiting applications, broadly classified into primary and secondary approaches. Further, the exemplars drawn from latest research demonstrate real-time application of fibers with embedded security features. This review also provides a critical and comparative analysis of fabrication approaches for smart optical fibers, emphasizing scalability, mechanical performance, and the advantages as well as limitations associated with spinning techniques, polymer matrices, and incorporated optical agents. Finally, current limitations and future perspectives on sustainable fabrication and multifunctional integration are also discussed to guide the development of next-generation optical anti-counterfeiting applications. Overall, this review offers a comprehensive reference framework to guide future innovations and broaden the applications of anti-counterfeiting strategies in fibrous materials.