An inkjet printing device includes a stage; an inkjet head disposed above the stage and comprising nozzles through which ink is discharged, the ink including bipolar elements extending in a direction; an ink circulation part which supplies the ink to the inkjet head, and to which the ink remaining after being discharged from the inkjet head is supplied; and at least one sensing part disposed between the inkjet head and the ink circulation part and sensing a number of the bipolar elements that are discharged through the nozzles.

A liquid ejecting head includes: a pressure chamber substrate; and a communication plate, in which the pressure chamber substrate includes a first pressure chamber that extends in a first direction and applies pressure to a liquid, and a first supply channel, and the communication plate includes a first communication channel that extends in a second direction intersecting with the first direction and communicates with the first supply channel, and a second supply channel that communicates with the first supply channel and the first pressure chamber.

A liquid ejecting head includes a first pressure compartment extending in a first direction; a second pressure compartment extending in the first direction; a first communication passage continuous from the first pressure compartment and extending in the first direction; a second communication passage continuous to the second pressure compartment and extending in the first direction; a third communication passage continuous from the first communication passage and extending in a second direction intersecting with the first direction; a fourth communication passage continuous to the second communication passage and extending in the second direction; a fifth communication passage continuous from the third communication passage and continuous to the fourth communication passage and extending in the first direction; and a nozzle provided on the fifth communication passage.

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.

An aspect of the present disclosure is a liquid ejection apparatus including: a liquid ejection head including a conversion element that generates energy required to eject liquid, a first protection layer that blocks contact between the conversion element and the liquid, a second protection layer that partially covers the first protection layer and functions as a first electrode, a second electrode that is electrically connected to the first electrode through the liquid, and an ejection port that ejects the liquid, and a control unit configured to control a potential difference between the first electrode and the second electrode in printing to a predetermined value by changing at least one of potentials of the first electrode and the second electrode. The control unit sets the potential difference based on at least one of a condition and a configuration of the liquid ejection head.

In some examples, a fluid ejection die includes a plurality of nozzles arranged in a plurality of nozzle columns, the plurality of nozzle columns distributed across a width of the fluid ejection die in a staggered manner, wherein nozzles of each respective nozzle column of the plurality of nozzle columns are spaced apart along a length of the fluid ejection die, wherein the plurality of nozzle columns includes a first pair of neighboring nozzle columns that are spaced by a first distance across the width. The plurality of nozzle columns includes a second pair of neighboring nozzle columns that are spaced by a second distance across the width, the second distance being larger than the first distance.

Provided are an inkjet printing apparatus and a recovery method capable of suppressing ink thickening in the ejection openings in the suction process for the ejection openings. A vacuum wiper is moved being in contact with the ejection opening surface of the print head to perform a vacuum wiping process for the arrayed ejection openings sequentially. Ink is circulated in flow paths including the flow paths communicating with the ejection openings for which the vacuum wiping process has been finished.

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.

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 plurality of wall surfaces that constitute inner walls of the pressure compartment includes a surface of the recessed portion and the first wall surface, and an angle formed by the first surface and the first wall surface is greater than 90° and less than 180°.