| 摘要 |
PURPOSE:To always direct ink jet to the same direction when the injection of ink is started and stopped, by providing a non-symmetric part to an orifice. CONSTITUTION:If a protruded part 11 and a recessed part 12 for making an orifice 10 asymmetric are provided to the lower side of the orifice 10, the ink droplet injected from the orifice 10 always rises from the lower side and stopped in a state directed to the lower side when the injection of ink is started and stopped. The asymmetric part may be provided to the A-part, B-part or C-part of the outlet side of the orifice or in the orifice. By providing the above- mentioned asymmetric part, the disturbance of ink jet is eliminated when the injection of the ink is started and stopped and stop and start can be performed in such a state that ink jet is always directed to a desired direction. As a result, the contamination of a head periphery, especially, the contamination of a charging electrode can be prevented and reliability is enhanced. |
