EFFECT OF PAPERBOARD SURFACE MODIFICATIONS ON ELECTRICAL CONDUCTIVITY OF PRINTED UHF RFID ANTENNAS

Abstract

The effect of surface roughness and water contact angle of commercial paperboard before and after surface modification by calendering, coating and calendering and plasma treatment on the functionality of UHF RFID antennas printed with thermal transfer aluminum ribbon was evaluated. A hydrophilic surface was created by coating or plasma treatment, which improved the wettability of the paperboard surface, the spreading of the thermoplastic tie layer and theadhesion of the conductive aluminum layer. Anew paper product was created with permanent surface wettability by coating, without theneed for plasmatreatment before printing. Theplasma treatment provided time-limited wettability, needed only during printing, and made it possible to restore the original hydrophobic surface of thepaperboard. In addition to themeaning of these surface modifications, the importance and need to reduce the surface roughness was confirmed, as the higher surface roughness of the paperboard limited the effect of the plasma treatment in terms of its printability and the functionality of the printed aluminum antenna. The printability of the paperboard and the functionality of the printed antennas were evaluated using electrical conductivity. The electrical conductivities of the dipole and inductor loop of the UHF RFID antennas printed on modified paperboards varied depending on theantenna design.