LAUSR

The processes of wetting and solvent evaporation in the drying sessile conductive ink droplets formed by inkjet printing are clarified for characterization to be referenced for diverse applications. The electric resistance of the PEDOT:PSS ink line patterns on the nanopaper, the film material of cellulose nanofibers, is affected by the shape and structure of the wire, which are dominated by the elementary process of the droplet drying dynamics. The evaporation flow rate of the ink droplets on the nanopapers decreases at the later stage of the drying process. This is dominated by the decrease in the air–liquid interfacial surface area, while the evaporation flux is roughly constant. The wetting of droplets formed by the inkjet printer is different from the quasi-static droplet placement. The contact angles of sufficiently smaller droplets are smaller, indicating higher apparent wettability because of the momentum effect. This is distinguished from the gravity effect. The conductive particles in the ink hel...