On-demand regulation of decoloration rate of photochromic polymers for self-erased time-dependent information encryption

Abstract

Nowadays, high security of information encryption technology, especially those time-dependent encrypting, are increasingly important, but remains a great challenge. Herein, we developed a novel time-dependent information encryption technology, which based on a series of photochromic spirooxazine-contained polymers with different rigidity. The color of these polymers can be reversibly switched between blue and colorless via irradiation of UV light and storage in dark. The decoloration rate of these polymers can be modulated by changing the rigidity of the polymers. By taking full advantage of this property, two self-erased time-dependent information encryption strategies were established. After UV irradiation, the encoded information was self-erased with time in dark. During this process, fake or correct information was generated. The correct information was only identified at a pre-designed period of time. This time-dependent property implies new prospect for information encryption with a high level of security.