Double‐State Anticounterfeiting Labels Based on Light‐Emitting Polymer‐Stabilized Blue Phase

Abstract Anticounterfeit labels with multiple information‐carrying functions serve a critical role in boosting security and minimizing counterfeit‐related losses, whose development remains challenging. Here, a security label with the ability to encode information in reflective and fluorescent sates is fabricated from light‐emitting polymer‐stabilized blue phase (LE‐PSBP) liquid crystals (LCs). The LE‐PSBP with temperature‐dependent reflective color can be encoded with information by UV irradiation through photomasks. On the other hand, introduction of a fluorescent molecule, which can be easily photocyclized upon UV irradiation, enables the convenient encoding of fluorescent information without impacting the reflective information. As an illustration, a security label with distinct information in reflective and fluorescent states is demonstrated. Such innovative security labels have tremendous potential to provide a platform for multi‐information encoding to enhance the protection level in anticounterfeiting technology.