Ecofriendly, Low Temperature Processible Conductive Paste with StrongDurability and High Adhesion Strength Using Catechol Lipid Bioresin

Abstract

Oriental lacquer, which is a catechol lipid-based bio-resin, has gathered significant attention as an eco-friendly natural material due to its high durability, strong adhesion strength, and spontaneous curability at room temperature. In this work, we demonstrated eco-friendly conductive silver paste based on the catechol-lipid bioresin of urushiol lacquer (UL-Ag paste) that can be cured at room temperature. This UL-Ag paste has low electrical resistivity and has advantages of urushiol lacquer such as strong adhesion strength, and high hardness. Urushiol lacquer induced reduction of silver salts at the surface of the silver filer, resulting in the low resistance of the UL-Ag paste (below 4.4 × 10？5 Ω cm). The highly ordered microstructure of silver fillers was formed during the cross-linking process of the urushiol lacquer and it enhanced conductive film of superior hardness (over 200 MPa), antiscratch capability, and strong adhesion strength (class 5B). We have invested the effect of urushiol lacquer on excellent properties of conductive film through FT-IR, thermal analysis (DSC, TGA), SEM analysis, and characterization of urushiol lacquer. Finally, we demonstrated the facile room-temperature processability and screen printability of the UL？Ag paste by fabricating a printed antenna and three-dimensional (3D) electrode assembly based on a plastic 3D block.