A new absorption/fluorescence dual-mode hydrochromic dye for water-jet printing and anti-counterfeiting applications†
Most hydrochromic materials only exhibit either absorption or fluorescence changes, which greatly restrict their applications. Herein, we reported a new hydrochromic dye capable of a absorption/fluorescence dual-mode change via transforming rhodamine B from its structure of lactone to pyrroline. Taking advantage of its excellent physico-chemical properties, this hydrochromic dye has been applied in water-jet printing, which has fast coloration speed, good reversibility, high resolution, and absorption/fluorescence two-mode display. Based on its fluorescence property, its application in information encryption has been illustrated. This dual-mode hydrochromic dye shows great potential in multifunctional integrated devices.