A fluid propelling apparatus, including a plastic compound, a MEMS at least partially surrounded by the compound, and a heat sink next to the MEMS, to transfer heat away from the MEMS, wherein the heat sink is at least partly surrounded by the compound.

In an embodiment, a fluid ejection device includes a thin-film layer formed over a substrate. A primer layer is formed over the thin-film layer, and a chamber layer is formed over the primer layer that defines a fluidic channel leading to a firing chamber. The fluid ejection device includes a slot that extends through the substrate and into the chamber layer through an ink feed hole in the thin-film layer. The fluid ejection device also includes a particle tolerant extension of the primer layer that protrudes into the slot. In some implementations, the particle tolerant primer layer extension extends across a full width of the slot.

In an implementation, a printhead includes a printhead die molded into a molding. The 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 may pass directly to the back surface. The die also has a nozzle health sensor molded into the molding to detect defective nozzles in the printhead die.

A system and method of printing on a strand element with a printer head. The printer head includes a conduit and a cavity formed within the conduit, wherein the cavity is configured to receive the strand element and pass the strand element from a first end of the cavity to a second end of the cavity. The printer head also includes a first set of fluid nozzles formed on the conduit and positioned on a perimeter of the cavity around a first target location within the cavity, wherein each of the fluid nozzles in the first set is positioned to aim at the first target location, and the first target location corresponds to a location of a first segment of the strand element when the strand element is positioned within the cavity.

A liquid ejection head substrate includes a heating resistor array including a plurality of heating resistors and a protective film covering at least one of the heating resistors. The liquid ejection head substrate further includes a supply opening array and an electrode. The supply opening array is disposed on a side of a surface of the liquid ejection head substrate on which the protective film is provided. The supply opening array includes a plurality of supply openings through which a liquid is supplied arranged in a direction along the heating resistor array. The electrode is disposed on the side of the surface in a space between the supply openings adjacent to each other in a direction along the supply opening array. The electrode is configured such that a voltage is applied between the electrode and the protective film.

A circuit die may include an outermost circuit layer having electrical transmission routing and an alignment target overlying the outermost circuit layer.

In a liquid ejection head in which ejection modules are arrayed on a flow path forming member, each ejection module includes a recording element substrate provided on a support member. The recording element substrate includes a liquid supply channel, a liquid collection channel, and ejection ports. The support member includes supply-side liquid communication ports communicating with the liquid supply channel and collection-side liquid communication ports communicating with the liquid collection channel. The supply-side liquid communication ports and the collection-side liquid communication ports are alternately provided along the direction in which the ejection modules are arrayed. The closest pair of liquid communication ports in the adjacent ends of two adjacent ejection modules are both supply-side or collection-side liquid communication ports.

Provided is a liquid ejection head that can suppress variation in the circulation flow rate or the pressure of the liquid among a plurality of pressure chambers and suppress a difference in temperature distribution between adjacent element substrates to suppress image unevenness. The liquid ejection head includes a plurality of ejection modules including an element substrate in which a plurality of ejection orifices that eject a liquid are aligned in an array. In one ejection module of the ejection modules adjacent to each other, the liquid is supplied from one side of an ejection orifice array, and the liquid is collected from the other side of the ejection orifice array, and in the other ejection module of the ejection modules adjacent to each other, the liquid is supplied from the other side, and the liquid is collected from the one side.

In a case where air bubbles exist in ink at the time of circulating the ink within a liquid ejection module, the amount circulating ink runs short and stability of ejection is blocked. The liquid ejection module has: a pressure chamber that communicates with an ejection port and which stores a liquid; an energy generation element that produces energy for causing a liquid to be ejected from the ejection port; a supply flow path that supplies a liquid to the pressure chamber; a collecting channel that collects a liquid from the pressure chamber; a liquid sending chamber that connects to the collecting channel; a connection flow path that connects the liquid sending chamber and the supply flow path; and a liquid sending unit configured to circulate a liquid, and the liquid sending chamber has a continuously inclined structure.

A cleaning method of a liquid ejection head where recording element substrates having an ejection orifice forming-face having ejection orifice arrays which are aligned, and at least one array ejects a different recording liquid than another, includes wiping and preliminary ejection. In the wiping, a wiping member is caused to move along and wipe the arrays. In the preliminary ejection, before the wiping of the entire ejection orifice forming-face is completed, preliminary ejection from the wiped ejection orifices is started. The wiping and preliminary ejection are sequentially performed from a recording element substrate at one end to a recording element substrate at the other end.