A piezoelectric printhead includes a piezoelectric printing device, a manifold, a U-shaped flexible printed wiring element and an interconnection element. The piezoelectric printing device includes a piezoelectric plate and a substrate with at least one row of drop ejectors; first and second ink inlet ports; signal lines leading to corresponding signal input pads; and ground traces leading to at least one ground return pad. The manifold is fluidically connected to the ink inlet ports. The flexible printed wiring element includes a device connection region and a pair of legs that extend from the device connection region. The pair of legs includes signal connection lines and at least one ground connection line. The interconnection element is disposed between the device connection region of the flexible printing wiring element and a contact layer of the piezoelectric printing device that includes the signal input pads and the at least one ground return pad.

A liquid ejection head includes an ejection opening; a passage in which an energy generation element is disposed; an ejection opening portion that allows communication between the ejection opening and the passage; a supply passage for allowing the liquid to flow into the passage; and an outflow passage for allowing the liquid to flow out to the outside. An expression of H.sup.−0.34×P.sup.−0.66×W>1.7 is satisfied when a height of the passage is set to H [μm], a length of the ejection opening portion is set to P [μm], and a length of the ejection opening portion is set to W [μm].

A liquid discharging head includes a nozzle plate having a plurality of nozzles from which liquid is discharged; a plurality of individual liquid chambers that are communicably connected to the plurality of nozzles, respectively; a common liquid chamber that supplies liquid to the plurality of individual liquid chambers; and a circulation common liquid chamber that leads to a plurality of circulation channels. A part of the common liquid chamber overlaps the circulation common liquid chamber from a direction in which liquid is discharged from the nozzles, and another part of the common liquid chamber overlaps the circulation common liquid chamber from a direction orthogonal to both the direction in which liquid is discharged from the nozzles and a direction in which the nozzles are aligned.

A die for a printhead is described herein. The die includes a number of fluid feed holes disposed in a line parallel to a longitudinal axis of the die, wherein the fluid feed holes are formed through a substrate of the die. A number of fluidic actuators are proximate to the fluid feed holes to eject fluid received from the plurality of fluid feed holes. The die includes logic circuitry to operate the fluidic actuators, wherein the logic circuitry is disposed on a first side of the plurality of fluid feed holes. Power circuitry to power the plurality of fluidic actuators is disposed on an opposite side of the fluid feed holes from the logic circuitry. Activation traces are disposed between each of the fluid feed holes to couple the logic circuitry to the power circuitry.

A fluidic die may include a fluid channel layer defining a number of fluid channels therein, a slot layer disposed on a side of the fluid channel layer, and a first fluid slot and a second fluid slot defined in the slot layer. At least one of the fluid channels fluidically couples the first fluid slot to the second fluid slot. The first fluid slot and the second fluid slot are defined in the slot layer along a length of the fluidic die.

There are provided an inkjet head, an inkjet image forming apparatus, a nozzle plate manufacturing method, and an inkjet head manufacturing method capable of improving durability against wiping on an ink discharge surface. The inkjet head includes a nozzle substrate including nozzle holes from which ink is discharged. The nozzle substrate has an irregularity structure formed on an ink discharge surface such that neither ink particles contained in the ink nor a wiping member that wipes the ink discharge surface get caught by the irregularity structure.

A fluid ejection device may include fluid actuators, ejection chambers adjacent the fluid actuators, nozzles extending from the ejection chambers, and fluid feed holes to supply fluid from a fluid supply passage to the ejection chambers. The fluid feed holes have ports connected to the ejection chambers. The ports are sized to pass bubbles formed by the fluid actuators out of the ejection chambers.

Provided is a liquid discharging apparatus including a container containing a liquid composition containing water, an organic solvent, and a polyurethane resin, and a discharging head. The discharging head includes: an individual liquid chamber including a circulation flow path through which the liquid composition circulates; and a nozzle communicating with the individual liquid chamber and through which a liquid droplet of the liquid composition is discharged. The solid content of the polyurethane resin in the liquid composition is 7.0% by mass or greater but 20.0% by mass or less.

A piezoelectric printing device includes a piezoelectric plate and a substrate with at least one row of drop ejectors. Each drop ejector includes a pressure chamber on a first side of the substrate and a nozzle on a second side of the substrate. The piezoelectric plate is attached to the substrate by a bonding layer. A first electrode layer is disposed on a first surface of the piezoelectric plate that is proximate to the first side of the substrate. The first electrode layer includes signal lines and ground traces corresponding to each pressure chamber. A second electrode layer including signal input pads and ground return pads is disposed on the first side of the substrate. Signal lines and ground traces in the first electrode layer are electrically connected to signal input pads and ground return pad(s) respectively on the second electrode layer through solder joints.

A piezoelectric printing device includes a substrate and a piezoelectric plate. At least one row of drop ejectors is disposed along a row direction. Each drop ejector includes a nozzle in fluid communication with a pressure chamber that is bounded by side walls. The piezoelectric plate has a first surface that is disposed proximate to the first side of the substrate. A bonding layer is disposed between the piezoelectric plate and the substrate. An electrode layer is disposed between the first surface of the piezoelectric plate and the bonding layer. The electrode layer includes a signal line corresponding to each pressure chamber. Each signal line leads to a signal input pad. The electrode layer also includes ground traces disposed on both sides of each pressure chamber. The ground traces are electrically connected to at least one common ground bus that is electrically connected to at least one ground return pad.