a first sloped portion that is provided between the first wall surface and the third wall surface includes a first constituting surface that extends in a third direction between the first direction and the second direction.

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.

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.

In example implementations, an apparatus is provided. The apparatus includes a channel, an opening in the channel, and a heating element aligned with the opening on opposite sides of the channel. The channel contains a droplet of a first liquid containing a particle, wherein the droplet is carried within a second liquid in the channel. The heating element is to heat the first liquid to generate a vapor in the first liquid to eject the droplet of the first liquid through the opening.

A head module includes a pressure chamber, a piezoelectric member, a supply manifold, a return manifold, and a damper portion. The pressure chamber is configured to hold liquid therein and in fluid communication with a nozzle orifice. The piezoelectric member is configured to apply pressure to liquid held in the pressure chamber. The supply manifold is in fluid communication with the pressure chamber and configured to allow liquid to flow into the pressure chamber therefrom. The return manifold is in fluid communication with the pressure chamber and configured to allow liquid not ejected from the nozzle orifice to flow thereinto. The damper portion is positioned between the supply manifold and the return manifold when viewed in plan from a nozzle surface of the head module. The nozzle surface has the nozzle orifice defined therein. The damper portion includes a particular plate having a particular recessed portion.

A liquid discharge head, comprising an insulating member arranged on a substrate, a resistive heating element arranged in the insulating member and configured to generate thermal energy used to discharge a liquid, a bubble chamber provided above the insulating member and configured to generate bubbles of the liquid based on the thermal energy, and a temperature detection element capable of detecting a temperature in the bubble chamber, wherein the temperature detection element is arranged between the resistive heating element and the bubble chamber and in a conductive layer closest to the bubble chamber in a plurality of conductive layers provided with respect to the insulating member.

Fluid is continuously recirculated through a thermal fluid-ejection printhead. Prior to firing a thermal resistor of the printhead to thermally eject a drop of the fluid through a nozzle of the printhead, the fluid is recirculated on-demand through a chamber of the printhead between the nozzle and the thermal resistor. The thermal resistor is fired to thermally eject the drop of the fluid through the nozzle. The fluid has a concentration of solids greater than 12% by volume.

An apparatus includes a reservoir and a printhead. The printhead includes a support structure including a deformable portion defining at least a top surface of a pumping chamber, a flow path extending from the reservoir to the pumping chamber to transfer fluid from the reservoir to the pumping chamber, and an actuator disposed on the deformable portion of the support structure. A trench is defined in a top surface of the actuator. Application of a voltage to the actuator causes the actuator to deform along the trench, thereby causing deformation of the deformable portion of the support structure to eject a drop of fluid from the pumping chamber.

An apparatus includes a reservoir and a printhead. The printhead includes a support structure including a deformable portion defining at least a top surface of a pumping chamber, a flow path extending from the reservoir to the pumping chamber to transfer fluid from the reservoir to the pumping chamber, and an actuator disposed on the deformable portion of the support structure. A trench is defined in a top surface of the actuator. Application of a voltage to the actuator causes the actuator to deform along the trench, thereby causing deformation of the deformable portion of the support structure to eject a drop of fluid from the pumping chamber.

A liquid ejection apparatus includes a liquid storing unit capable of storing liquid, a liquid ejection unit including an ejection port that is capable of ejecting the liquid, and a pressure control unit that receives the liquid from the liquid storing unit and allows the liquid having a pressure controlled to be within a predetermined pressure range to be supplied to the liquid ejection unit. Additionally, the liquid ejection apparatus includes a first circulation unit that supplies the liquid having the pressure controlled by the pressure control unit to the ejection port while circulating the liquid between the liquid ejection unit and the pressure control unit, and a second circulation unit that circulates the liquid between the liquid storing unit and the pressure control unit.