A liquid ejection apparatus includes a liquid ejection head and a controller. The controller configured to perform: determining whether a discharge failure occurs in a first nozzle; in a case where it is determined that the discharge failure occurs in the first nozzle, determining whether a certain condition is satisfied; in a case where it is determined that the certain condition is satisfied: applying a flushing signal to a second driving element; applying a driving signal to the second driving element; determining whether the discharge failure occurs in a second nozzle; in a case where it is determined that the discharge failure does not occur in the second nozzle, executing a first purge; and in a case where it is determined that the discharge failure occurs in the second nozzle, executing a second purge.

There is provided liquid discharging head including; channel member which includes plates stacked in a first direction and adhered to each other via adhesive, and in which individual channels each including nozzle and pressure chamber communicated with the nozzle is formed. The plates include first plate and second plate adhered to adhesion surface of the first plate via the adhesive. Hollows each construct one of the individual channels are opened in the adhesion surface. The hollows are arranged side by side in second direction orthogonal to the first direction in the adhesion surface, and three or more grooves are formed in the adhesion surface between two of the hollows adjacent to each other in the second direction, each of the three or more grooves extending in third direction which is orthogonal to the first direction and which crosses the second direction.

A liquid discharge head includes a flow passage substrate which is formed with individual flow passages, the individual flow passages including nozzles and pressure chambers communicated with the nozzles respectively, the pressure chambers being open on a surface of the flow passage substrate; a sealing member which is adhered to the surface via an adhesive and which seals the pressure chambers; and an actuator substrate which has a piezoelectric layer adhered to a surface of the sealing member on a side opposite to the flow passage substrate via an adhesive and individual electrodes formed on a side opposite to the sealing member with respect to the piezoelectric layer. The sealing member is composed of a material different from a material of the piezoelectric layer; and the surface has an adhesion area to which the sealing member is adhered and a non-adhesion area to which the sealing member is not adhered.

There is provided liquid discharging head including individual channels, supply throttles, and return throttles formed in plates. The supply throttles are formed in first plate of the plates and the return throttles are formed in second plate of the plates. Each of the supply throttles has cross section which is rectangle having first and second sides. Each of the return throttles has cross section which is rectangle having first and second sides. The length of the first side of each of the supply throttles and the length of the first side of each of the return throttles are substantially identical. The length of the second side of each of the supply throttles and the length of the second side of each of the return throttles are substantially identical. Aspect ratio of each of the supply throttles and aspect ratio of each of the return throttles are substantially identical.

A liquid discharge head includes a flow passage member, a sealing member, and an actuator member. The flow passage member is formed with individual flow passages each including a nozzle and a pressure chamber and the flow passage member has a surface on which the pressure chamber is open. The sealing member is arranged on the surface and seals the pressure chamber. The actuator member has a piezoelectric layer, a driving electrode, and a high electric potential portion. The piezoelectric layer is adhered to a first surface of the sealing member on a side opposite to the flow passage member, via a first adhesive having an insulating property. The driving electrode is arranged on a side opposite to the sealing member with respect to the piezoelectric layer at a position overlapped with the pressure chamber in a first direction orthogonal to the surface.

an adhesive having a first amount exists on a side of the first piezoelectric element line, of a joint of the wiring substrate and the pressure chamber substrate or the vibration plate, an adhesive having a second amount that is larger than the first amount exists on a side of the second piezoelectric element line of the wiring substrate, of the joint, and a first discharging element related to the first piezoelectric element line is different from a second discharging element related to the second piezoelectric element line.

There is provided a piezoelectric actuator, including: a vibration plate; a first piezoelectric body; a second piezoelectric body; a first electrode disposed on a first surface of the first piezoelectric body; a second electrode disposed on a second surface of the second piezoelectric body; an intermediate electrode disposed on an intermediate surface of the first piezoelectric body and overlapping with the first and second electrodes; an intermediate trace connected to the intermediate electrode on the intermediate surface and drawn out to one side in a first direction beyond the first piezoelectric body and the second piezoelectric body; a first trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace; and a second trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace.

A liquid ejecting head includes: a plurality of head chips having nozzles; a holder holding the plurality of head chips; and a planar heater disposed on the holder and heating the holder, in which the heater includes an outer peripheral region along an outer edge of the holder and a middle region positioned inside the outer peripheral region in a plan view, and a heat generation amount per unit time of the outer peripheral region is larger than a heat generation amount per unit time of the middle region.

A lead-free piezoelectric material includes perovskite-type metal oxide containing Na, Nb, Ba, Ti, and Mg and indicates excellent piezoelectric properties. The piezoelectric material satisfies the following relational expression (1): 0.430≤a≤0.460, 0.433≤b≤0.479, 0.040≤c≤0.070, 0.0125≤d≤0.0650, 0.0015≤e≤0.0092, 0.9×3e≤c−d≤1.1×3e, a+b+c+d+e=1, where a, b, c, d, and e denote the relative numbers of Na, Nb, Ba, Ti, and Mg atoms, respectively.

A liquid discharge head is provided in which heat of a heat sink is less apt to transfer to a head body. The liquid discharge head includes a head body 2a having a discharge hole for discharging a liquid therethrough, a driver IC 93 configured to control driving of the head body 2a, a casing 91 which is disposed on the head body 2a and has openings 91a and 91b on a side surface of the casing, and a heat sink 90 which is disposed on the openings 91a and 91b of the casing 91 and configured to dissipate heat generated in the driver IC 93, and a thermal insulation part 91e disposed between the heat sink 90 and the head body 2a. This makes it possible to reduce the likelihood that the heat of the heat sink 91e transfers to the head body 2a.