Abstract
Sustainability in electronics has a growing importance due to, e.g. increasing electronic waste, and global and European sustainability goals. Printing technologies and use of paper as a substrate enable manufacturing of sustainable electronic devices for emerging applications, such as the multi-layer anti-counterfeit label presented in this paper. This device consisted of electrochromic display (ECD) element, NFC (near field communication) tag and circuitry, all fully roll-to-roll (R2R) printed and assembled on plastic-free paper substrate, thus leading to a sustainable and recyclable device. Our setup uses harvested energy from HF field of a smartphone or reader, to switch an electrochromic display after rectification to prove authenticity of a product. Our novelty is in upscaling the manufacturing process to be fully printable and R2R processable in high-throughput conditions simulating industrial environment, i.e. in pilot scale. The printing workflow consisted of 11 R2R printed layers, all done in sufficient quality and registration. The printed antennas showed sheet resistance values of 32.9±1.9 mΩ/sq. The final yield was almost 1500 fully printed devices, and in R2R assembly over 1400 labels were integrated with 96.5% yield. All the assembled tags were readable with mobile phone NFC reader. The optical contrast (ΔE*) measured for the ECDs was over 15 for all the printed displays, a progressive switching time with a colour change visible in less than 5 s. The smart tag is ITO-free, plastic-free, fully printed in R2R and has a good stability over 50 cycles and reversible colour change from light to dark blue.
Original language | English |
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Pages (from-to) | 2921-2934 |
Journal | The International Journal of Advanced Manufacturing Technology |
Volume | 117 |
Issue number | 9-10 |
DOIs | |
Publication status | Published - Dec 2021 |
MoE publication type | A1 Journal article-refereed |
Funding
Part of the facilities used were provided by the Academy of Finland Research Infrastructure “Printed Intelligence Infrastructure (PII-FIRI, grant no. 32020). Open access funding provided by Technical Research Centre of Finland (VTT). Research leading to this paper was carried out in Supersmart research project that has received funding from the European Institute of Innovation and Technology (EIT), a body of the European Union, under the Horizon 2020, the EU Framework Programme for Research and Innovation.