“Acrostic” Encryption: Stress‐Manipulation on Information Display

Abstract Polymers are ideal materials for information printing and storage and encryption through multiple channels. In this study, the visible color, fluorescent, and stress‐color are combined to print information. Stress‐color is achieved using an acid‐tunable dynamic reaction between a β‐diketone and an amine group via the light‐induced transformation of spiropyran (SP), which also directly prints the visible color information. The color and fluorescent patterns are stable via the reaction between SP and amine released from a dynamic enaminone structure. By achieving the stress‐color information coding, the data is further encrypted in an “acrostic” form by programmatically coding the information at several stages. The pattern or information in stress‐color is closely related to the decoding strain, whereas the fluorescent and color patterns display all the information written in various strains. As a result, the secret information is hidden among public data, resulting in acrostic encryption.