Feng Dengchong, Guo Qi, Huang Zhenjie, Zhou Baiyang, Gong Li, Lu Shaolin, Yang Yuzhao, Yu Dingshan, Zheng Zhikun, Chen Xudong
Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Guangdong Engineering Technology Research Center for High-Performance Organic and Polymer Photoelectric Functional Films, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China.
Instrumental Analysis Research Center, Sun Yat-sen University, Guangzhou, 510275, China.
Adv Mater. 2024 Jun;36(23):e2314201. doi: 10.1002/adma.202314201. Epub 2024 Mar 12.
As counterfeit techniques continue to evolve, ensuring the security of conventional "static" encryption methods becomes increasingly challenging. Here, the viscoelasticity-controlled relaxation is introduced for the first time in a bilayer wrinkling system by regulating the density of hydrogen bond networks in polymer to construct a "dynamic" encryption material. The wrinkling surface can manipulate light during the dynamic relaxation process, exhibiting three stages with frosted glass, structural color, and mirror reflection. By regulating the viscoelasticity of skin layer through UV irradiation, the wavelength and the relaxation rate of the wrinkles can be controlled. As a result, dynamic wrinkling anti-counterfeiting patterns and time-resolved multistage information encryption are achieved. Crucially, the encryption material is developed as an anti-counterfeiting label for packing boxes in daily applications, allowing the encrypted information to be activated manually and identified by naked eyes, surpassing the existing time-resolved encryption materials in utilization potential. Besides, the dynamic hydrogen bond networks are extended to various dynamic interaction networks, demonstrating the versatility of the dynamic encryption strategy. This work not only provides an additional dimension for dynamic information encryption in daily practical use, but also offers theoretical guidance for the development of advanced optical anti-counterfeiting and smart display materials in the future.
随着造假技术不断发展，确保传统“静态”加密方法的安全性变得越来越具有挑战性。在此，通过调节聚合物中氢键网络的密度，首次在双层皱纹系统中引入粘弹性控制的弛豫，以构建一种“动态”加密材料。皱纹表面在动态弛豫过程中能够操纵光线，呈现出磨砂玻璃、结构色和镜面反射三个阶段。通过紫外线照射调节表层的粘弹性，可以控制皱纹的波长和弛豫速率。结果，实现了动态皱纹防伪图案和时间分辨多阶段信息加密。至关重要的是，该加密材料被开发成日常应用中包装盒的防伪标签，使加密信息能够手动激活并通过肉眼识别，在利用潜力方面超越了现有的时间分辨加密材料。此外，动态氢键网络被扩展到各种动态相互作用网络，展示了动态加密策略的通用性。这项工作不仅为日常实际应用中的动态信息加密提供了一个新的维度，也为未来先进光学防伪和智能显示材料的发展提供了理论指导。
