Super Adhesive Fluorescent Materials for Encrypted Messages, Underwater Leak Repair, and Their Potential Application in Fluorescent Tattoos

Abstract Achieving high‐performance luminescence for underwater bonding remains a significant challenge in materials science. This study addresses this issue by synthesizing a luminescent material based on an aggregation‐induced emission (AIE) monomer and copolymerizing it with lipoic acid (LA) to create an AIE supramolecular polymer. The resulting copolymer exhibits strong fluorescence under ultraviolet (UV) irradiation at 365 nm due to the AIE of TPEE and enables underwater adhesion. The P(LA‐TPEE) polymer demonstrates potential for digital encryption and decryption of quick response (QR) codes underwater. Furthermore, it can dissolve well in anhydrous ethanol, producing an environment‐friendly and super waterproof adhesive. Most notably, the P(LA‐TPEE) solution can be sprayed on human skin, creating an invisible tattoo that only became visible under UV light due to the hydrogen bond (H‐bond) and π–π structures. This smart tattoo can be quickly wiped away with alcohol, avoiding the painful and harmful process of tattoo removal. It can also be repeatedly applied to draw the preferred tattoo pattern. This AIE supramolecular polymer shows great potential in underwater adhesion and repair, underwater message encryption, and non‐toxic and painless invisible tattooing. Overall, this study provides a valuable approach for material design in the future.