Minh Nguyen Hoang, Kim Kwanoh, Kang Do Hyun, Yoo Yeong-Eun, Yoon Jae Sung
Nano Lithography and Manufacturing Research Center, Korea Institute of Machinery and Materials (KIMM) Daejeon 34103 South Korea
Dept. Nanomechatronics, University of Science and Technology (UST) Daejeon 34113 South Korea.
Nanoscale Adv. 2024 Oct 22;6(23):5853-60. doi: 10.1039/d4na00814f.
Labels with structural color based on photonic crystals (PCs) have drawn significant attention due to their unique color emission, offering promising solutions for anti-counterfeiting applications. However, to meet the demands of future high-security applications, conventional structural color labels require further improvement. This study introduces a novel approach to fabricate highly encrypted anti-counterfeiting labels by combining close-packed and non-close-packed monolayers of nanoparticles (NPs) onto adhesive surfaces. The photonic crystals, arranged in specific geometric shapes, exhibit overt-covert characteristics. The hidden label is only revealed under specific external triggers, such as attaching or removing a transparent cover film. The principle of color modulation of the photonic crystal is elucidated, highlighting the role of packing density and refractive index matching. Additionally, the scalability and cost-effectiveness of the fabrication process in this study are expected to facilitate future commercialization. Various anti-counterfeiting applications, including water-responsive labels and multi-layer authentication, are demonstrated also, which enables higher security levels and versatility of this study.
基于光子晶体（PCs）的结构色标签因其独特的颜色发射而备受关注，为防伪应用提供了有前景的解决方案。然而，为了满足未来高安全性应用的需求，传统的结构色标签需要进一步改进。本研究引入了一种新颖的方法，通过将紧密堆积和非紧密堆积的纳米颗粒（NPs）单层组合到粘性表面上来制造高度加密的防伪标签。以特定几何形状排列的光子晶体具有显性-隐性特征。隐藏的标签仅在特定的外部触发条件下才会显示出来，例如贴上或揭下透明覆盖膜。阐明了光子晶体颜色调制的原理，突出了堆积密度和折射率匹配的作用。此外，本研究中制造工艺的可扩展性和成本效益有望促进未来的商业化。还展示了各种防伪应用，包括水响应标签和多层认证，这使得本研究具有更高的安全性和多功能性。
