Cellulose as an Eco-Friendly and Sustainable Material for Optical Anticounterfeiting Applications: An Up-to-Date Appraisal.

The falsification of documents, currency, pharmaceuticals, branded goods, clothing, food products, and packaging leads to severe consequences. Counterfeited products can not only pose health risks to consumers but also cause substantial economic losses that can negatively impact the global markets. Unfortunately, most anticounterfeiting strategies are easily duplicated due to rapid technological advancements. Therefore, innovative and cost-effective antiforgery techniques that can offer superior multilevel security features are continuously sought after. Due to the ever-growing global awareness of environmental pollution, renewable and eco-friendly native biopolymers are garnering wide attention in anticounterfeiting applications. This review highlights the potential use of cellulose-based eco-friendly materials to combat the counterfeiting of goods. The initial section of the review focuses on the structure, properties, and chemical modifications of cellulose as a sustainable biomaterial. Further, the topical developments reported on cellulose and nanocellulose-based materials used as fluorescent security inks, films, and papers for achieving protection against counterfeiting are presented. The studies suggest the convenient use of celluose and modified cellulose materials for promising optical antiforgery applications. Furthermore, the scope for future research developments is also discussed based on the current critical challenges in the fabrication of cellulose-based materials and their anticounterfeit applications.