Mechael Sara S, D'Amaral Gloria M, Carmichael Tricia Breen
Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada N9B 3P4.
ACS Appl Mater Interfaces. 2023 Sep 20;15(37):44422-44432. doi: 10.1021/acsami.3c07035. Epub 2023 Sep 5.
The proliferation of printed electronic devices is feeding the growth of the Internet of Things, with devices deployed everywhere to collect and communicate data. At the same time, the increase in low-cost disposable devices is a cause for serious environmental concern. In particular, widely used plastic substrates such as poly(ethylene terephthalate) are persistent hazards to the environment. Paper is promising as a greener substrate for printed electronics because it is biodegradable and sourced from renewable materials as well as being low cost and compatible with roll-to-roll printing. However, the porous microstructure of paper promotes wicking of functional inks, leading to poor electrical performance and printing resolution. Hydrophobic coatings applied to the surface of paper create a planarized, printable surface, but these materials may compromise biodegradability and/or recyclability. This paper describes a new resist-free patterning method for printed paper-based electronics that takes advantage of the porous structure of paper. Debossed contact printing uses the pressure from a debossing tip to compress the porous structure of paper and create a patterned relief structure. Printing functional inks with an unpatterned roller deposits ink only on the raised regions of the relief structure. We demonstrate debossed contact printing of silver, carbon black, and conducting polymer inks and show that this new fabrication method is suitable for the fabrication of printed devices with dense features. We demonstrate the fabrication of antennas and patterned electrodes for RFID and smart wallpaper applications, respectively.
印刷电子设备的激增推动了物联网的发展，各类设备被部署到各处用于收集和传输数据。与此同时，低成本一次性设备的增加引发了严重的环境问题。特别是，诸如聚对苯二甲酸乙二酯等广泛使用的塑料基板对环境存在持久危害。纸张有望成为印刷电子领域更环保的基板，因为它可生物降解，源自可再生材料，成本低且与卷对卷印刷兼容。然而，纸张的多孔微观结构会促进功能性墨水的毛细作用，导致电气性能和印刷分辨率不佳。应用于纸张表面的疏水涂层可创建一个平整的可印刷表面，但这些材料可能会损害生物降解性和/或可回收性。本文介绍了一种用于印刷纸基电子产品的新型无抗蚀剂图案化方法，该方法利用了纸张的多孔结构。压印接触印刷利用压印尖端的压力压缩纸张的多孔结构，形成图案化的浮雕结构。用无图案的滚筒印刷功能性墨水时，墨水只会沉积在浮雕结构的凸起区域。我们展示了银、炭黑和导电聚合物墨水的压印接触印刷，并表明这种新的制造方法适用于制造具有密集特征的印刷设备。我们分别展示了用于射频识别（RFID）和智能壁纸应用的天线和图案化电极的制造。
