DROPLET DISCHARGE HEAD, LIQUID CARTRIDGE, DROPLET DISCHARGE RECORDING DEVICE, AND FORMATION METHOD OF PROTECTION SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To obtain a droplet discharge head which enables stable ink ejection and reduction of the deterioration of a piezoelectric element and achieves high reliability.SOLUTION: A droplet discharge head 101 includes: a nozzle plate 103 having nozzle holes 109; a drive element substrate 112 having a piezoelectric element 116 which generates a pressure in a liquid chamber 110a leading to the nozzle holes 109 through a diaphragm 115; and a protection substrate 113 which is joined to the drive element substrate 112 through an adhesive 125 forming a space 114 with the piezoelectric element 116. The protection substrate 113 includes a communication hole 113b for allowing the space 114 to connect with an external atmosphere.