Self-erasable dynamic surface patterns via controllable elastic modulus boosting multi-encoded and tamper-proof information storage

Dynamic surface patterns (DSPs) have attracted significant interest in anti-counterfeiting, enabling information to be stored, encrypted and decrypted in response to external stimuli. However, creating dynamic surface patterns, capable of controlling wrinkling time and independently modulating different information in both wrinkled and fluorescent states, remains a tremendous challenge. These limit DSPs to further enhance tamper-proofing capacity and extend the information storage density. Here, a rationally designed patterning strategy based on controllable elastic modulus was demonstrated to fabricate self-erasable dynamic surface patterns (S-DSPs) that increase information storage density. These novel S-DSPs strategically integrated amino co-oligomers (ACOs) with the 9-anthracenemethanol (9-AM) as skin layers, designing a bilayer multi-encoding system which could carry several different types of information with wrinkled and fluorescent patterns. The ACOs with relatively low molecular weight can endow the elastic modulus of skin layers with a wide range of regulation. As a result, the difference between the compressive strain and the critical wrinkle strain in the bilayer system would be precisely modulated by photo-dimerization to form quick-response (minimum < 1 min) and self-erasable (3 min∼8 days) wrinkled patterns for S-DSPs. Meanwhile, the fluorescence pattern could be independently erased and reprogrammed without affecting the change in the wrinkle pattern under modulus-controlled conditions. Moreover, controllable self-erasure in S-DSPs significantly develops tamper-proof capabilities in a supply chain. This original strategy could provide a new approach to the tamper-proof, high-density, and multi-encoded information storage in the product security or inkless printing.