A piezoelectric device includes a piezoelectric body, a vibration plate that vibrates when the piezoelectric body is driven, a first electrode positioned between the piezoelectric body and the vibration plate, and a second electrode positioned to be separated from the first electrode by the piezoelectric body. The piezoelectric body has an active portion that is a part sandwiched between the first electrode and the second electrode in a first direction along a thickness direction of the piezoelectric body, and a change width of a dC/dV value, which represents a change in capacitance with respect to a change in a voltage applied along a second direction orthogonal to the first direction, from one end of the active portion on a side of the first electrode to the other end of the active portion on a side of the second electrode in the first direction is 10% or less.

An inkjet print head includes a plurality of droplet jetting devices. The plurality of droplet jetting devices is formed of a nozzle layer defining, for each of the plurality of droplet jetting devices, a nozzle, a membrane layer carrying, on a membrane, a restrictor layer and an actuator for generating pressure waves in a liquid in a pressure chamber that is connected to the nozzle. The actuator is positioned in an actuator chamber in the restrictor layer, and a distribution layer defining a supply line for supplying the liquid to the pressure chamber. The restrictor layer includes an inlet restrictor having a cross-section and an outlet restrictor positioned on opposites sides of the actuator and having a cross-section that is different from the cross-section of the inlet restrictor.

A liquid discharge device in which a drive circuit substrate that outputs a first drive signal supplied to a first electrode, a substrate, a first drive circuit that has a first circuit element in which a ground potential is supplied to one end and outputs the first drive signal, a first capacitor in which one end is electrically coupled to the second electrode and a ground potential is supplied to the other end, and a second capacitor in which one end is electrically coupled to the second electrode and a ground potential is supplied to the other end, the substrate includes a first surface and a second surface, the first capacitor is a chip capacitor, the second capacitor is an electrolytic capacitor, the first circuit element and the first capacitor are provided on the first surface, and the second capacitor is provided on the second surface.

A liquid discharge device including a drive circuit substrate that drives a piezoelectric element of a liquid discharge head, and that includes a substrate which includes a first wiring layer having a first wiring through which the first drive signal propagates, a second wiring layer having a second wiring through which the second drive signal propagates, and a third wiring layer located between the first wiring layer and the second wiring layer and having a fourth wiring through which the reference voltage signal propagates, in which a third wiring through which the third drive signal propagates is provided on any one of the first wiring layer, the second wiring layer, and the third wiring layer.

A liquid discharge device including a first piezoelectric element that has a first electrode and a second electrode and discharges a liquid from a first nozzle by being driven, a second piezoelectric element that has a third electrode and a fourth electrode and discharges a liquid from a second nozzle by being driven, a reference voltage signal propagation path that electrically couples the second electrode and the fourth electrode and propagates the reference voltage signal supplied to a first coupling point to the second electrode and the fourth electrode, and a first capacitor electrically coupled to the reference voltage signal propagation path at a second coupling point provided in the reference voltage signal propagation path, in which the second coupling point is located between the first coupling point and the second electrode in the reference voltage signal propagation path.

A liquid ejecting system includes a head unit that includes a pressure chamber, a drive element driven by an applied drive waveform, a vibration plate that vibrates by drive of the drive element, and a nozzle through which a liquid is ejected by a pressure applied in the pressure chamber by vibration of the vibration plate, and an input portion to which an input parameter for detecting an ejection failure of the liquid based on residual vibration of the vibration plate is input from a server through a network connection portion.

A liquid ejecting system includes a head unit that includes a nozzle for ejecting a liquid, a pressure chamber communicating with the nozzle, and a drive element for applying pressure fluctuation to a liquid in the pressure chamber by supplying a drive pulse, an acquisition portion that acquires output information regarding a usage condition of the head unit, a first connection portion that is communicably connected to a server through a network, a first output portion that outputs the output information through the first connection portion, a first input portion to which input information regarding a waveform of the drive pulse supplied to the drive element is input through the first connection portion. A decision portion that decides the waveform of the drive pulse supplied to the drive element based on the input information.

A liquid ejecting system includes a head unit that includes a nozzle for ejecting a liquid, a pressure chamber communicating with the nozzle, and a drive element for applying pressure fluctuation to a liquid in the pressure chamber by supplying a drive pulse, a first connection portion that is communicably connected to a server through a network, a decision portion that decides a waveform of the drive pulse supplied to the drive element based on first input information, and a first input portion to which the first input information is input from the server through the first connection portion.

A white ink jet ink composition according to the present disclosure includes hollow resin particles, resin particles, and water. The hollow resin particles have a glass transition temperature of 120° C. or more, the resin particles are composed of an acrylic resin or a urethane resin, and the content of the resin particles is 5% by mass or more relative to the total mass of the ink composition.

A substrate having a recessed portion, a diaphragm, and a piezoelectric actuator are provided, the diaphragm includes a first layer containing silicon as a constituent element, and a third layer disposed between the first layer and the piezoelectric actuator and containing zirconium as a constituent element, and a laminated side surface of the first layer and the third layer is covered with a moisture-resistant protective film containing at least one selected from the group made of oxide, nitride, metal, and diamond-like carbon.