The data that support the findings of this study are available within the article and its Supporting Information files. Extra data are available from the corresponding authors upon reasonable request.

Interest and effort toward new materials for rewritable paper have increased dramatically because of the exciting advantages for sustainable development and better nature life cycle. Inspired by how nature works within living systems, herein, we have used fluorans, as a concept verification, to endow original acidochromic, basochromic or photochromic molecules with broader properties, such as switchable with solvent, water, heat, electricity, stress, other force, etc., via simplified methods (i.e., via variation of submolecular structure or microenvironments). The hydrochromic visual change and reversible behavior of selected molecules have been explored, and the primary mechanism at the atomic or subatomic level has been hypothesized. In addition, several newly demonstrated hydrochromic fluorans have been utilized for water-jet rewritable paper (WJRP), which exhibit great photostability, high hydrochromic contrast, and fast responsive rate and which can be reused at least 30 times without significant variation. The water-jet prints have good resolution and various colors and can keep legibility after a few months or years. This improved performance is a major step toward practical applications of WJRP.

A simple and general platform for thermochromic fluorescent materials with excellent performance and multiple feasible applications.

The development and application of novel activated furan copolymers is reported. The platform provides a colorimetric method for sensing amines in aqueous media through the generation of a highly colored donor–acceptor Stenhouse adduct (DASA). Furthermore, the resulting DASA–polymer conjugates, which are obtained after amine sensing, are characterized to determine fundamental structure–property relationships for this emerging class of negative photochromic species.

No abstract