S1 is a sum of the areas of a plurality of individual electrodes formed on a first plane of a piezoelectric body of a liquid discharge head, S2 is an area of a first common electrode formed on a second plane, S3 is an area of a second common electrode formed on a third plane, D1 is a distance between a neutral plane and the first plane in a stacking direction, D2 is the distance between the neutral plane and the second plane in the stacking direction, and D3 is the distance between the neutral plane and the third plane in the stacking direction. Then, D1×S1+D2×S2>D3×S3 is satisfied. The liquid discharge head includes a plurality of conductor layers which are formed on the third plane, without contact with the second common electrode and without contact with each other.

A liquid ejecting device includes a flow path member, an actuator, a pump, and a controller. The flow path member includes a flow path configured to direct flow of a pseudoplastic liquid through the flow path member. The actuator is configured to cause droplets to be ejected. The pump is configured to cause the liquid to flow sequentially through a supply reservoir, a plurality of supply manifolds, a plurality of supply flow paths, and a plurality of pressure chambers. The controller is configured to adjust a flow rate of the liquid to a prescribed target flow rate. The flow path has a flow path shape in which an average viscosity of the liquid in the plurality of supply flow paths is less than or equal to half an average viscosity of the liquid in the plurality of supply manifolds when the flow rate is equal to the target flow rate.

There is provided a drive board a manufacturing cost of which can be reduced while enhancing a liquid ejection performance. The drive board according to an embodiment of the present disclosure is a drive board which is applied to a liquid jet head, and outputs a drive signal to a jet section, and includes a first wiring layer and a second wiring layer opposed to each other along a direction perpendicular to a board surface, at least one drive device which is mounted on the first wiring layer, and is configured to generate the drive signal, a first power supply wiring line which is arranged in the first wiring layer, and is a wiring line configured to supply drive power toward the drive device, a differential line which is arranged in the first wiring layer, and is a line configured to transmit a differential signal toward the drive device, and a second power supply wiring line which is arranged in the second wiring layer, which is electrically coupled to the first power supply wiring line via a first through hole, and is opposed to a first area in the differential line. A wiring width in the second power supply wiring line is larger than a line width of the first area in the differential line.

The head chip includes an actuator plate having ejection channels and non-ejection channels extending in a Y direction and arranged alternately in an X direction, an intermediate plate overlapped with the actuator plate in a Z direction, and provided with communication holes communicated with the ejection channels and through holes communicated with the non-ejection channels, and a nozzle plate overlapped with the intermediate plate in the Z direction in a state of closing the through holes, and provided with nozzle holes which are communicated with the communication holes, jet liquid contained in the ejection channels, and are formed at positions corresponding to the ejection channels. The non-ejection channels are communicated with an outside of the head chip. The through holes are each disposed at an inner side in the X direction of the inner surfaces extending in the Y direction of the non-ejection channel viewed from the Z direction.

There are provided a method of manufacturing a head chip capable of suppressing the occurrence of the failure in the process of forming the actuator plate to thereby increase the yield ratio, and a method of manufacturing a liquid jet head using the above method of manufacturing a head chip. The method of manufacturing a head chip according to an embodiment of the present disclosure is a method of manufacturing a head chip having an actuator plate adapted to apply pressure to liquid so as to jet the liquid. Forming the actuator plate includes forming a plurality of grooves on a surface of a piezoelectric substrate having one end and the other end so as to extend from the one end side toward the other end side, forming a conductive film on the surface of the piezoelectric substrate provided with the plurality of grooves, forming a laser processing area in the conductive film between the grooves adjacent to each other by performing laser processing from a start point on the one end side of the piezoelectric substrate to an end point on the other end side, and forming a surface removal area in at least a part including the start point and the end point out of the surface of the piezoelectric substrate by performing surface removal processing in a direction crossing the direction in which the laser processing is performed.

Isolation between electrodes is ensured to enhance resistance to a liquid. A conductive film is provided to a surface of a piezoelectric substrate, and laser processing is performed in a groove extending direction on the conductive film between a first groove and a second groove provided to the piezoelectric substrate to thereby form a laser processing area where the conductive film is removed to the surface of the piezoelectric substrate between the first groove and the second groove. In forming the laser processing area, an irradiation operation with a laser is performed along a plurality of laser processing lines extending in the groove extending direction. Further, the irradiation operation with the laser is performed a plurality of times for each of the laser processing lines, and the irradiation operations with the laser performed along the same laser processing line of the plurality of laser processing lines are performed at a time interval from when ending a previous irradiation operation with the laser to when starting a subsequent irradiation operation with the laser.

A liquid discharge head includes a flow channel member, a pressurization part, a plurality of discharge holes, a flexible substrate, a cover member, and a heater. The flow channel member includes a first surface and a second surface that is positioned on an opposite side of the first surface. The pressurization part is positioned on the first surface. The plurality of discharge holes are positioned on the second surface. For the flexible substrate, a one-end part thereof that is positioned on the pressurization part is electrically connected to the pressurization part. The cover member covers the one-end part of the flexible substrate. The heater is positioned on the cover member.

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.

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.