A liquid discharge head includes an electric connecting portion between a flexible wiring substrate and a contact wiring substrate. The contact wiring substrate has a first surface on which a contact pad is provided and a second surface opposite the first surface. The electric connecting portion is disposed on the second surface side of the contact wiring substrate.

There is provided a liquid discharge head including a piezoelectric body having a plurality of individual electrodes and a first common electrode, and a plurality of conductor layers. The plurality of individual electrodes have first to fourth individual electrode arrays, and the first common electrode has first and second extending portions, a plurality of first projecting portions, and a plurality of second projecting portions. Each of the first projecting portions overlaps partially with one of the plurality of individual electrodes forming the second individual electrode array along the stacking direction, and each of the second projecting portions overlaps partially with one of the plurality of individual electrodes forming the third individual electrode array along the stacking direction. The plurality of conductor layers are formed between the plurality of first projecting portions and the plurality of second projecting portions, without contacting the first common electrode and without contacting each other.

A liquid discharge head includes a common flow channel extending along a first direction, and individual flow channels arranged along the first direction. Each individual flow channel includes a first pressure chamber and a second pressure chamber arranged along the first direction, each of which communicates with the common flow channel, a nozzle located away from the first and second pressure chambers in a second direction orthogonal to the first direction, and a connection flow channel connecting the first pressure chamber, the second pressure chamber, and the nozzle with each other. One end of the connection flow channel in the second direction communicates with the first pressure chamber and the second pressure chamber, and the other end thereof in the second direction communicates with the nozzle. The connection flow channel extends along the second direction from the one end to the other end thereof in the second direction.

In order to provide an inkjet head using an adhesive containing an epoxy resin as a main agent and an imidazole-based curing agent as a curing agent, capable of securing a time for joining work before curing, and having excellent long-term reliability, and a production method for the inkjet head, constituent members are bonded to each other by an adhesive containing at least an epoxy resin as a main agent, a microencapsulated imidazole-based curing agent as a curing agent, and an alcohol that dissolves the microcapsules at a low temperature, and preferably, a residue of the microcapsules dissolved by the alcohol is dispersed in the cured epoxy resin.

A liquid droplet discharge head includes a reservoir having a slit portion through which a flexible substrate is extracted outward. A closing member is disposed in the slit portion, and a sealing resin is disposed on the closing member.

A liquid discharge apparatus includes a nozzle plate with nozzles and actuators and a drive controller. First and second nozzles are directly adjacent to each other in a first direction. First and third nozzles are directly adjacent to each other in a second direction. The drive controller is configured to apply a drive signal to first, second, and third actuators corresponding to the first, second, and third nozzles, respectively, during a drive cycle. A difference between a first timing at which the drive signal is applied to the first actuator and a second timing at which the drive signal is applied to the second actuator and a difference between the first timing and a third timing at which the drive signal is applied to the third actuator is an odd number multiple of a half of an inherent vibration cycle of the liquid discharge apparatus.

A liquid ejecting apparatus includes a drive circuit that outputs a drive signal, wherein the drive circuit includes a modulation circuit that modulates a base drive signal to output a modulation signal, an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal, a demodulation circuit that demodulates the amplified modulation signal to output the drive signal, and a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, wherein the substrate includes a first face and a second face opposite to the first face, wherein the demodulation circuit includes a first coil and a second coil electrically coupled in parallel with the first coil, and wherein the first coil is positioned so as to overlap at least part of the second coil in a direction normal to the first face.

A piezoelectric element includes: a first electrode and a second electrode; and a piezoelectric layer provided between the first electrode and the second electrode and having a perovskite structure, in which 0<P1/P2≤0.5 and 0<P1 where, when a positive predetermined voltage is applied to the piezoelectric layer, then a voltage applied to the piezoelectric layer is set to 0 V for 0.1 seconds, and then a triangular wave voltage waveform having a maximum voltage of the predetermined voltage is applied to the piezoelectric layer to obtain a hysteresis curve drawn counterclockwise, P1 is a residual polarization amount at a start point of the hysteresis curve and P2 is a residual polarization amount at an end point of the hysteresis curve.

An inkjet printing apparatus comprises an inkjet head disposed above a stage and including nozzles through which ink including bipolar elements is discharged, the bipolar elements each having regions partially doped with different polarities. At least part of the nozzles is deflected from a direction in case that the nozzles are in a deflected state.

A liquid ejection head comprises: a first print element substrate having an ejection port for ejecting a liquid; a support member supporting the first print element substrate; and an adhesive agent provided for adhering the first print element substrate to the support member, wherein the first print element substrate includes a supply port opposed to the support member and communicating with the ejection port, a first surface opposed to the support member and surrounding the supply port, and a second surface opposed to the support member and provided along at least a part of an outer edge of the first surface and retracted from the first surface relative to the support member, and the adhesive agent is filled in a first space between the first surface and the support member, and at least a part of a second space between the second surface and the support member.