Improved Continuous Inkjet for Selective Area Coating Using High-Viscosity Insulating Inks

While drop-on-demand (DOD) inkjet has been broadening its applications, especially in manufacturing sectors such as printed electronics, continuous inkjet (CIJ) has been limited to use in conventional graphics and marking areas. So far, there have been few attempts to use functional materials in CIJ printing despite the advantages of its high-speed printing capability and relatively low implementation costs. Herein, the performance of CIJ in terms of printable ink viscosity, print area, and printing speed is significantly improved. For demonstration, selective area printing methods using insulation inks are presented. The selective area coating is very difficult to implement since charged droplets becoming closer together can increase undesirable charge repulsion effects among them. To reduce the charge interaction among the charged droplets and maximize the printing efficiency, a new voltage driving scheme for selective area coating applications is proposed.