Inorganic Luminescent based Anti-Counterfeiting Technologies: From Material Innovation to Ink Engineering and Pattern Deposition

• Emerging multi-level and multimodal systems, including up-conversion, persistent luminescence, and stimuli-responsive phosphors that difficult to imitated single-mode emission have been discussed • Unlike existing literature, review covers an in-depth analysis of ink formulation. It covers rheological parameters—such as shear-thinning behaviour, thixotropic recovery, and surface tension—dictate the "readability" and spatial resolution. • Review article explore the state-of-the-art in deposition techniques and the shift toward Physically Unclonable Functions (PUFs) and AI-driven verification. Rise in counterfeiting of passports, currency notes, confidential documents, and high-end consumer products thrives for evolution of new age solutions as it not only affects individuals but also poses a serious threat to Nation’s economy. This review critically assesses the progression from conventional security options to modern-day photoluminescent material-based strategies. Extensive research is underway to develop innovative luminescent materials with advanced optical properties. However, their adoption in industry remains limited due to engineering challenges and difficulties in formulating these materials into practical forms such as stable inks, paints, tags, or films. Therefore, the present review focuses on bridging this gap on the requirements for successful luminescent ink formulation, including compositional variety and necessary rheological studies. Various printing and deposition techniques are systematically illustrated and compared. State of art in luminescent anti-counterfeiting technology, integrating material advancements, ink formulation, pattern deposition, and smartphone-based encryptions techniques for real-world deployment are outlined.