Advanced anticounterfeiting polymer inks for high-level encryption and authentication technologies

Smart polymeric materials have garnered significant attention in the field of anticounterfeiting. As traditional anticounterfeiting inks are frequently copied and counterfeited over time, creating a demand for more advanced anticounterfeiting inks. This review introduces innovative encryption mechanisms and methods for advanced anticounterfeiting inks, including Förster resonance energy transfer, charge and electron transfer, aggregation-induced emission, phase separation, white light emission, double encryption, and unclonable inks. The mechanisms of chromism, luminescence emission, and preparation methods of these inks are discussed, providing insights into their potential applications in security technologies, including inks against counterfeiting and innovative encryption techniques. Polymers have gained significant attention in this field because of their versatility, the ability to integrate diverse functional properties, increasing reusability and lifetime, photostability, photo-fatigue resistant characteristics, and ease of application on various substrates. This review introduces advanced methods and mechanisms, such as dynamic encryption, double encryption, and unclonable anticounterfeiting, for combating forgery and counterfeiting to protect documents and luxury products. This is achieved through polymer-based high-security anticounterfeiting inks. Finally, the application methods of these inks on different substrates is an important challenge, for which printing has gained significant attention because of its simplicity, high rate of production, reproducibility, and precise applicability.