Thermal-magnetic inkjet mechanism for the application of micro pattern fabrication on the highly unlevel microarea

We proposed a novel type of inkjet mechanism (thermal-magnetic driving) employing the magnetic material Curie temperature. In the magnetic circuit composed of N-S of magnet poles, the magnetizing field through temperature-sensitive magnetic fluid inside the circuit will show no-gradient uniform vector field. When the temperature-sensitive magnetic fluid inside the circuit was getting a rapid temperature rise locally, its magnetization will disappear locally, so that results in a precipitous magnetic gradient and pumping force (Maxwell stress). There, the moving elements like piezo-plates are absolutely unnecessary, and a high temperature rise like in the thermal bubble type inkjet is also not necessary. By employing a low Curie-temperature magnetic fluid (Ferrite or FeNiCr nanoparticle), it is possible to generate enough of ejecting power at 50-120°C. In the proposed inkjet system, magnetic fluid ink was used to alleviate the bursting phenomenon of the ink-drop and enlarge the flying distance of ink-drop. The pumping power was realized by the Maxwell stress generated from the precipitous magnetic gradient of the magnetic fluid in the inkjet head. The working mechanism was verified by the analysis software COMSOL MULTIPHYSICS simulation and the optimal structure was analyzed. The fabrication process was also discussed. The detailed simulation results will be presented in the conference presentation.