| 摘要 |
PURPOSE:To enhance quality of an image with aqueous ink and to reduce a voltage by generating ink bubble by electric decomposition between a pair of electrodes or on one of them, and then so applying a voltage as to vary the volume of the bubble by discharging. CONSTITUTION:When electrodes 22, 23 are conducted therebetween, hydrogen 24 is generated by electric decomposition of aqueous ink 20 and heat is generated at the electrode 22. The surface of the electrode 22 is covered with hydrogen bubble 24 and vaporized ink, the electrodes 22, 23 are insulated therebetween to stop electric conduction. Then, a boundary 25 between the bubble 24 and the ink becomes the same potential as that of the electrode 23, and when an electric field intensity between a raised surface and the electrode is raised, a discharge is inducted in the bubble 24, pressure in an ink supply passage 26 is raised due to the heat at the time of discharge, the expansion of the bubble 24 and bubble generated due to the vaporization of the ink to inject ink 20 from a nozzle 21. In this case, the electric field intensity is reduced by the expansion of the bubble to stop discharging. |
