Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy , Fujian Normal University , Fuzhou 350117 , China.
Fujian Provincial Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices , Xiamen 361005 , China.
ACS Appl Mater Interfaces. 2018 Nov 21;10(46):40149-40155. doi: 10.1021/acsami.8b14625. Epub 2018 Nov 8.
Nowadays, urged by the high demand to reduce paper consumption, rewritable paper receives more and more attention. However, it is a great challenge to conveniently fabricate the rewritable paper which has long legible time of information and is easy to use simultaneously. Here, we report a new type of long-lasting rewritable paper based on color-memorizing thermochromic dye and photothermal-converting toner, which is fabricated by a two-step printing process. The rewritable paper demonstrates excellent rewriting performances (legible time > 6 months and reversibility > 100 times). The thermochromic effect is based on a temperature-driven phase change mechanism, accompanied by a lactone ring tautomerism of crystal violet lactone. The color of the rewritable paper rapidly changes from blue to colorlessness when the temperature is higher than 65 °C, and the colorless state can be maintained at room temperature. The color returns to blue when the temperature is lower than -10 °C. By using an electrothermal pen, a thermal printer, and near infrared (NIR) light, characters and images with high resolution can be handwritten, thermal-printed, and photoprinted on the rewritable paper. The written/printed information can be cleaned under lower temperature or can be quickly erased by NIR light. This rewritable paper is easy for large-scale production and will have promising opportunities in practical applications, such as long-lasting information recording and reading, rewritable label, reprintable displays, and so on.
如今，由于人们强烈要求减少纸张消耗，可重复书写纸受到了越来越多的关注。然而，同时方便地制造具有长时间可读信息且易于使用的可重复书写纸是一个巨大的挑战。在这里，我们报告了一种基于彩色记忆热致变色染料和光热转化调色剂的新型长时可重复书写纸，它是通过两步打印工艺制造的。可重复书写纸表现出优异的重写性能（可读性时间>6 个月，可逆性>100 次）。热致变色效应基于温度驱动的相转变机制，伴随着晶体紫内酯的内酯环互变异构。当温度高于 65°C 时，可重复书写纸的颜色会迅速从蓝色变为无色，并且在室温下可以保持无色状态。当温度低于-10°C 时，颜色会恢复为蓝色。通过使用电热笔、热敏打印机和近红外（NIR）光，可以在手写、热敏打印和光打印可重复书写纸上书写高分辨率的字符和图像。书写/打印的信息可以在较低温度下清除，或者可以通过 NIR 光快速擦除。这种可重复书写纸易于大规模生产，在实际应用中具有广阔的前景，例如长时间信息记录和读取、可重复标签、可重印显示器等。
