| 摘要 |
PURPOSE:To effectively prevent an upheaval accumulation phenomenon of ink generated under the uniformization effect of an electrostatic field in a high-speed printing cycle, and make the upheaval of ink uniform in an optimum state by reducing the electrostatic field stepwise following the progress of a continuous printing cycle. CONSTITUTION:When a switching element 24 is turned ON/OFF in accordance with a signal which complies with image information, a heat signal A is applied to ink 3 from a corresponding thermal resistor 21. At the same time, an electrostatic signal S which forms an electrostatic field is applied to the ink 3, synchronously with the heat signal A. At that time, a voltage value of a variable high voltage supply 33 is reduced by 10V per printing cycle of 100 lines by means of an electrostatic control means 7. Therefore, the electromagnetic signal S is reduced stepwise per printing cycle of 100 lines, and then is applied to the ink 3. For this reason, when the electrostatic signal S is uniform, the attractive force brought to bear on an ink column 3a in an upheaval direction becomes weak by the stepwise reduction value of intensity of the electrostatic signal S. Subsequently, the upheaval of the rising ink column 3a is maintained almost at a constant level. |
