There is provided a liquid jetting apparatus, including: a first pressure chamber and a second pressure chamber arranged in a first direction; a first insulating film covering the first and second pressure chambers; a first piezoelectric element arranged to face the first pressure chamber with the first insulating film being intervened therebetween; a second piezoelectric element arranged to face the second pressure chamber with the first insulating film being intervened therebetween; a trace arranged between the first and the second piezoelectric elements adjacent to each other in the first direction; and a second insulating film covering the trace. An end, in the first direction, of a part of the second insulating film covering the trace between the first piezoelectric element and the second piezoelectric element is positioned inside an end of a partition wall partitioning the first pressure chamber and the second pressure chamber.

A method is provided for manufacturing a piezoelectric device including a piezoelectric element that is disposed above a diaphragm and that has a multilayer structure including a first electrode disposed above the diaphragm, a piezoelectric layer disposed on the first electrode, and a second electrode disposed on the piezoelectric layer. The method includes forming the multilayer structure including the first electrode, the piezoelectric layer, and the second electrode above the diaphragm, forming a voltage application electrode extending outwardly from an end of the second electrode to cover a region located above the piezoelectric layer in an inactive section having no second electrode, applying a voltage between the first electrode and the second electrode, and removing the voltage application electrode.

Provided are a vibrating plate, a first electrode provided over the vibrating plate, a piezoelectric layer provided over the first electrode, and a second electrode provided over the piezoelectric layer are provided. The piezoelectric layer is interposed between the first electrode and the second electrode. The piezoelectric layer includes an active portion of which at least one end portion is defined by the first electrode, and a non-active portion provided on an outside of the end portion of the first electrode for defining the active portion. The vibrating plate includes a first vibration portion under the non-active portion and a second vibration portion on an outside of the first vibration portion. The second vibration portion includes a taper part having the thickness which is increased toward the first vibration portion.

A liquid ejecting head includes a plurality of actuators, a plurality of pressure chambers that are provided so as to correspond to the actuators, and communicate with a common liquid chamber, a first member that defines the common liquid chamber, and includes a compliance sheet that absorbs vibrations of liquid on an upstream side of the common liquid chamber, and an inlet that is formed so as to penetrate the compliance sheet, a canopy portion that is provided at an open peripheral edge of the inlet of the first member, and has a receiving surface to which the compliance sheet is joined, and a receiving portion that is provided opposite the inlet across the canopy portion, and receives liquid introduced from the inlet.

The head has a passage member having a nozzle and a pressurizing chamber which is communicated with the nozzle and is positioned on the side opposite to the side where the nozzle is opened, a piezoelectric actuator substrate which is superimposed on the passage member so as to cover the pressurizing chamber, and a flexible printed circuit which faces the piezoelectric actuator substrate from the opposite side to the passage member. The piezoelectric actuator substrate has a piezoelectric body which is exposed on the flexible printed circuit side. The piezoelectric body has a via hole opened toward the flexible printed circuit and has a projection portion at the edge part of the via hole which projects to the flexible printed circuit side.

A liquid discharge head includes a plurality of nozzles configured to discharge a liquid, a plurality of pressure chambers respectively communicating with the plurality of nozzles, a plurality of common-supply branch channels each communicating with two or more of the plurality of pressure chambers, a common-supply main channel communicating with each of the plurality of common-supply branch channels, a plurality of common-collection branch channels each communicating with two or more of the plurality of pressure chambers, and a common-collection main channel communicating with each of the plurality of common-collection branch channels. The plurality of nozzles is arrayed in a two-dimensional matrix in a first direction and a second direction intersecting with the first direction, the plurality of common-supply branch channels and the plurality of common-collection branch channels are alternately arranged in the second direction.

There is provided a liquid jet apparatus including a channel substrate having a plurality of pressure chambers and a film covering the plurality of pressure chambers, a piezoelectric layer, a plurality of individual electrodes, a common electrode, and a trace extending from one of the plurality of individual electrodes to pass through between two adjacent individual electrodes of the plurality of individual electrodes. An opening of the piezoelectric layer is provided between the two adjacent individual electrodes, and a metallic film is formed to cover the trace in such an area of the trace as to overlap with the opening positioned between the two adjacent individual electrodes.

A piezoelectric device includes a piezoelectric layer, a first moisture resistant layer, and a second moisture resistant layer stacked in this order. The first moisture resistant layer has a flexibility higher than that of the second moisture resistant layer, and the second moisture resistant layer has a moisture permeability lower than that of the first moisture resistant layer.

An inkjet head manufacturing method for an inkjet head that includes a head chip including: a nozzle ejecting ink; and a flow path substrate including an ink flow path which communicates with the nozzle and through which the ink flows, the method including: composite substrate manufacturing that is manufacturing a composite substrate including a plurality of regions which forms flow path substrates by being split; first protective film forming that is forming a first protective film on a surface of the composite substrate and an inner wall surface of the ink flow path; splitting that is splitting the composite substrate into the flow path substrates; and second protective film forming that is forming a second protective film on at least an exposed face in a split face of the flow path substrate generated in the splitting, the exposed face being exposed in a surface of the head chip.

The present invention may provide an inkjet head including a pressure chamber in which an aspect ratio of a partition wall is higher, the inkjet head less likely to be broken at the time of fabrication. An inkjet head of the present invention may include a diaphragm that vibrates by actuation of a piezoelectric body, and a pressure chamber a volume of which fluctuates by vibration of the diaphragm. In the pressure chamber, a region in contact with the diaphragm is divided from an adjacent pressure chamber or flow path by a partition wall formed of metal, and the partition wall has an aspect ratio of 1.3 or higher.