Provided is a method for manufacturing a liquid ejection head substrate and a method for manufacturing a liquid ejection head capable of reducing degradation of the quality of a printed image. To this end, in formation of a liquid ejection head substrate, a part required to have more precise relative positional relation or not required to have high fabrication precision is set as a first part, and for the first part, a single-shot exposure method is employed. Also, a part required to have higher fabrication precision is set as a second part, and for the second part, a split exposure method is employed.

Examples include a process comprising forming a molded panel that includes a fluid ejection die molded in the molded panel. The molded panel is formed with a mold chase and a release liner. The mold chase has a fluid slot feature that aligns with fluid feed holes of the fluid ejection die. The mold chase and release liner is released from the molded panel such that the molded panel has a fluid slot formed therethrough corresponding to the fluid slot feature of the mold chase, and the fluid slot is fluidly connected to the fluid feed holes of the fluid ejection die.

A nozzle plate of a fluid ejection head for a fluid ejection device, a fluid ejection head containing the nozzle plate, and a method for making the fluid ejection head containing the nozzle plate. The nozzle plate contains two or more arrays of nozzle holes therein and a barrier structure disposed on an exposed surface of the nozzle plate between adjacent arrays of nozzle holes, wherein the barrier structure deters cross-contamination of fluids between the adjacent arrays of nozzle holes.

In some examples, a print cartridge includes a monolithic molding, and a printhead die embedded into a molding. The printhead die has a front surface exposed outside the molding to dispense fluid drops through nozzles and an opposing back surface covered by the molding except at a channel in the molding through which fluid is to pass directly to the back surface. The printhead die also has a nozzle health sensor molded into the molding to detect defective nozzles in the printhead die.

A flow path structure which forms a flow path of liquid, includes: a light absorbing member (first substrate) having absorbing properties with respect to laser light; a light transmitting member (second substrate) which is joined to the light absorbing member and has transmitting properties with respect to the laser light; a first flow path (flow path) which is surrounded by a welding interface between the light absorbing member and the light transmitting member; and a second flow path which is formed in a flow path pipe (flow path pipe) which protrudes from a front surface opposite of the welding interface in the light transmitting member, and communicates with the first flow path, in which the flow path pipe is included in a region of the first flow path in a plan view from a direction orthogonal to the welding interface.

In some examples, a printhead can include a main printer fluid line, a firing chamber in fluid communication with the main printer fluid line to receive printer fluid from the main printer fluid line, and a resistor positioned in the firing chamber. The resistor can, for example, receive an electronic current to cause the resistor to heat up and eject printer fluid droplets from the printhead. The printhead can further include a photolithographically fabricated check valve positioned in the firing chamber. The check valve can, for example, be openable to allow filling of the firing chamber with printer fluid and closeable to at least partially seal the main printer fluid line from printer fluid blowback caused by the resistor.

A piezoelectric device includes a diaphragm provided on a side of one surface of a substrate, and a piezoelectric actuator having a first electrode, a piezoelectric body layer, and a second electrode which are stacked in a first direction on a side of a surface opposite to the substrate of the diaphragm, in which when one area far from an end portion of the second electrode is a first area and one area near the end portion of the second electrode is a second area, of two areas of the second electrode in a second direction intersecting the first direction, the second electrode has a stiffness of 17,000 N/m or more in the second area in the first direction, which is higher than a stiffness in the first area in the first direction, and a length in the second area in the first direction is equal to or less than a length of the piezoelectric body layer in the second area in the first direction.

When a filter for example is provided in a liquid supply path in the manufacture of a liquid ejection head, the filter can be prevented from being displaced or deformed. A manufacture method of a liquid ejection head having a liquid ejection unit for ejecting liquid and a liquid supply unit for supplying liquid to the liquid ejection unit has a processing of abutting a filter to a melting unit provided in the liquid supply unit and applying heat to the melting unit via the filter to melt the melting unit to thereby fix the filter to the melting unit, and a processing of burying the melting unit fixed to the filter by molding material.

A piezoelectric actuator is disclosed that may include a insulating layer, individual electrodes, a common electrode, and a piezoelectric layer. The common electrode may include divisional electrodes that are connected with one another. The individual electrodes may be disposed between the insulating layer and the piezoelectric layer while the piezoelectric layer may be disposed between the individual electrodes and the common electrode. Further, the divisional electrodes may be configured to face the individual electrodes.

There is provided a nozzle plate of an inkjet head, the nozzle plate including: a first surface that is bonded to an upper layer substrate by an adhesive; and a second surface in which an opening of a nozzle that ejects an ink is provided. A step is formed at an edge of the first surface.