| abstract |
An object of the present invention is to prevent a solution from adhering around a nozzle and prevent clogging of the nozzle. A water repellent having higher water repellency than a nozzle substrate by co-depositing a fluoride pitch after electroless Ni-P treatment of a nozzle substrate on a peripheral surface of a discharge port of the nozzle or an inner surface of the nozzle. The films 101 and 102 are formed. In addition, during standby for discharge, different voltages Va and Vb smaller than the discharge start voltage Vc are alternately applied to the solution to cause the liquid surface to oscillate in the nozzle and to stir the charged components in the solution. Alternatively, at the time of discharge standby, a predetermined voltage is applied to the piezo element 41, the internal volume of the solution chamber 24 is increased, and control is performed so that the liquid level of the solution is located in the nozzle by a change in the internal pressure. [Selection diagram] FIG. |