Kim Hyeli, Kwon Goomin, Park Cheolheon, You Jungmok, Park Wook
Department of Electronic Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea.
Institute for Wearable Convergence Electronics, Department of Electronics and Information Convergence Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea.
Micromachines (Basel). 2022 Jan 22;13(2):168. doi: 10.3390/mi13020168.
Anti-counterfeiting technologies for small products are being developed. We present an anti-counterfeiting tag, a grayscale pattern of silver nanowires (AgNWs) on a flexible substrate. The anti-counterfeiting tag that is observable with a thermal imaging camera was fabricated using the characteristics of silver nanowires with high visible light transmittance and high infrared emissivity. AgNWs were patterned at microscale via a maskless lithography method using UV dicing tape with UV patterns. By attaching and detaching an AgNW coated glass slide and UV dicing tape irradiated with multiple levels of UV, we obtained AgNW patterns with four or more grayscales. Peel tests confirmed that the adhesive strength of the UV dicing tape varied according to the amount of UV irradiation, and electrical resistance and IR image intensity measurements confirmed that the pattern obtained using this tape has multi-level AgNW concentrations. When applied for anti-counterfeiting, the gradient-concentration AgNW micropattern could contain more information than a single-concentration micropattern. In addition, the gradient AgNW micropattern could be transferred to a flexible polymer substrate using a simple method and then attached to various surfaces for use as an anti-counterfeiting tag.
针对小型产品的防伪技术正在研发中。我们展示了一种防伪标签，它是在柔性基板上的银纳米线（AgNWs）灰度图案。利用银纳米线具有高可见光透过率和高红外发射率的特性，制作出了能用热成像相机观察到的防伪标签。通过使用带有紫外线图案的紫外线切割胶带，采用无掩膜光刻法在微观尺度上对银纳米线进行图案化。通过将涂覆有银纳米线的玻璃载玻片与照射了多级紫外线的紫外线切割胶带进行粘贴和分离，我们获得了具有四种或更多灰度级的银纳米线图案。剥离测试证实，紫外线切割胶带的粘合强度随紫外线照射量而变化，电阻和红外图像强度测量证实，使用该胶带获得的图案具有多级银纳米线浓度。当用于防伪时，梯度浓度的银纳米线微图案比单浓度微图案能包含更多信息。此外，梯度银纳米线微图案可以通过一种简单的方法转移到柔性聚合物基板上，然后附着在各种表面上用作防伪标签。
