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.