Multidimensionally Programming Photoswitching via Orthogonal Covalent‐Noncovalent Chemistry for Dual‐Track Time‐Resolved Optical Encryption

ABSTRACT

Encoding targeted information into the temporal evolution of optical states, rather than relying on static on/off states, is essential for storage, optical encryption and anti‐counterfeiting. However, achieving multiple independent information‐display processes remains a challenge. Herein, a “dual‐track” time‐resolved optical encryption strategy is realized based on multidimensional programming of donor–acceptor Stenhouse adduct (DASA) photoswitching through orthogonal covalent‐noncovalent chemistry. The temporal optical evolution during the photo‐bleaching and thermal‐recovery processes can be predictably programmed through the orthogonal combination of noncovalent interactions and covalent incorporation between DASAs and polyurethanes. Distinct from conventional strategies, noncovalent hydrogen‐bonding interactions synchronously suppress the photo‐bleaching rate ( k _photo ) and thermal‐recovery rate ( k _dark ) through isomerization confinement, whereas covalent incorporation reshapes the isomerization energetics, simultaneously accelerating k _photo (2.4‐fold) and retarding k _dark (60% decrease). This orthogonal regulation mode is generally applicable across diverse polyurethane chemistries and establishes a four‐quadrant kinetic map for DASA photoswitching, providing multiple encoding units with distinguishable temporal optical evolution. The photo‐bleaching and thermal‐recovery processes function as two independent information‐display tracks, allowing encrypted information to appear in either track, both tracks, or neither track. This work establishes a novel “dual‐track” paradigm for optical encryption by decoupling information in reversible photoswitching processes.