Liquid discharge head, liquid discharge device, and liquid discharge apparatus

A liquid discharge head, comprising:

• a nozzle plate including a nozzle from which a liquid is to be discharged;
• a liquid chamber substrate on the nozzle plate, the liquid chamber substrate having an individual chamber communicating with the nozzle;
• a diaphragm on the liquid chamber substrate, the diaphragm defining a part of a wall of the individual chamber;
• a piezoelectric actuator on the diaphragm, the piezoelectric actuator including a piezoelectric body configured to deform the diaphragm in response to a drive voltage applied to the piezoelectric body;
• a wiring portion connected to the piezoelectric actuator to apply the drive voltage to the piezoelectric body of the piezoelectric actuator, the wiring portion covering a first region of the piezoelectric actuator;
• and
• a protective film, wherein
• the first region is at a first end of the piezoelectric actuator in a longitudinal direction of the individual chamber,
• a second region of the piezoelectric actuator is at a second end of the piezoelectric actuator opposite the first end in the longitudinal direction of the individual chamber,
• a first outer periphery of the piezoelectric body in the second region is interior of a second outer periphery of the individual chamber in the second region in the longitudinal direction,
• a gap region between the first outer periphery and the second outer periphery has:
• a first gap region having a first width in the longitudinal direction;
• and
• a second gap region having a second width in a transverse direction orthogonal to the longitudinal direction, the second width larger than the first width,
• the protective film covers a part of the first gap region in the second region, wherein
• the protective film includes multiple protruding portions protruding in the longitudinal direction toward the first region to cover multiple parts of the first gap region in the second region,
• the multiple protruding portions are arranged along the transverse direction, and
• the multiple protruding portions cover multiple parts of the piezoelectric body in the second region.