A liquid discharge head includes: a substrate, where a recording element is disposed; and a discharge orifice forming member, where a discharge orifice, facing the recording element, and configured to discharge the liquid, is formed. The liquid discharge head has a pressure chamber, a first liquid channel configured to supply liquid to the pressure chamber, and a second liquid channel configured to recover liquid from the pressure chamber. The substrate has a liquid supply channel connected to the first liquid channel to supply liquid to the first liquid channel, and a liquid recovery channel connected to the second liquid channel, to recover liquid from the second liquid channel. Pressure at an inlet portion of the liquid supply channel is higher than pressure at an outlet portion of the liquid recovery channel, and a flow velocity of liquid within the pressure chamber is 3 to 140 mm/s.

A recording apparatus that performs recording on a recording medium, includes a liquid discharge head including a plurality of element substrates each having a discharge port configured to discharge liquid and a heat element configured to heat the liquid, a channel member including a common supply channel configured to communicate with the plurality of the element substrates and to supply the liquid to the plurality of the element substrates, and a common collecting channel configured to communicate with the plurality of the element substrates and to collect the liquid from the plurality of the element substrates, wherein the common supply channel and the common collecting channel are respectively disposed out of alignment in a conveyance direction of the recording medium, and wherein, upstream of the element substrates, the recording apparatus comprises a heat unit configured to heat the liquid flowing in the common supply channel.

A wafer structure is disclosed and includes a chip substrate and an inkjet chip. The chip substrate is a silicon substrate fabricated by a semiconductor process on a wafer of 12 inches. The inkjet chips are formed on the chip substrate by the semiconductor process and diced into the inkjet chip. The inkjet chip includes plural ink-drop generators generated by the semiconductor process on the chip substrate. Each of the plurality of ink-drop generators includes a nozzle. A diameter of the nozzle is in a range between 0.5 micrometers and 10 micrometers. A volume of an inkjet drop discharged from the nozzle is in a range between 1 femtoliter and 3 picoliters. The ink-drop generators form plural longitudinal axis array groups having a pitch and plural horizontal axis array groups having a central stepped pitch equal to or less than 1/600 inches.

A liquid ejection head includes a liquid ejection head substrate having ejection elements that generate liquid ejecting energy, an ejection port formation member having ejection ports, and liquid chambers between the liquid ejection head substrate and the ejection port formation member to house liquid to be ejected through the ejection ports. The liquid ejection head substrate includes a substrate, an insulating film stacked on the substrate to insulate the ejection elements, communication ports in the substrate and the insulating film to communicate with the liquid chambers, and a liquid-resistant insulating film adherent to the ejection port formation member. The liquid-resistant insulating film covers the insulating film at its ejection port formation member side and includes a first portion partially contacting the ejection port formation member and a second portion covering the inner surfaces of the communication ports in the insulating film, the first and second portions being continuous.

A liquid ejection head includes a print element substrate including multiple ejection openings, pressure chambers, a common flow path, and pumps, the pumps being configured to circulate liquid between the common flow path and the pressure chamber; and a flow path member laminated to the print element substrate. The flow path member includes a supply flow path and a collection flow path, the supply flow path being configured to supply liquid to the print element substrate, and the collection flow path being configured to collect liquid that is not ejected. The supply flow path and the collection flow path have liquid connection with the same common flow path. A circulating pump generates a flow of liquid flowing in an order of the supply flow path, the common flow path, and the collection flow path, the circulating pump being provided at a position different from the print element substrate.

Printheads and printers are described herein. In one example, a printhead includes a plurality of nozzles configured to eject ink drops of different sizes wherein a low drop weight (LDW) drop is ejected through a nozzle with a circular bore (CB), and a high drop weight (HDW) drop is ejected through a nozzle with a non-circular bore (NCB).

The present invention provides a fine bubble generating apparatus capable of generating fine bubbles efficiently. The present invention includes a fluid flow passage that includes a narrow portion in at least a part thereof, a heating part capable of heating a liquid flowing through the fluid flow passage, and a controlling unit that controls the heating part. The controlling unit controls the heating part to generate film boiling in the liquid to generate ultrafine bubbles.

A liquid discharge head includes an element substrate including a plurality of discharge ports configured to discharge liquid in a discharge direction onto a recording medium, and a heating element configured to heat the liquid, and a flow path member including a supply flow path configured to supply the liquid to the element substrate and a collection flow path configured to collect the liquid from the element substrate. The supply flow path and the collection flow path extend in a longitudinal direction of the flow path member and at least a part of the supply flow path and at least a part of the collection flow path overlap each other when being viewed in the direction parallel to the discharge direction.

A wafer structure is disclosed and includes a chip substrate and a plurality of inkjet chips. The chip substrate is a silicon substrate fabricated by a semiconductor process. At least one inkjet chip is directly formed on the chip substrate by the semiconductor process and diced into the at least one inkjet chip for inkjet printing. Each of the inkjet chip includes a plurality of ink-drop generators produced by a semiconductor process and formed on the chip substrate. Each of the ink-drop generators includes a thermal-barrier layer, a resistance heating layer, a conductive layer, a protective layer, a barrier layer, an ink-supply chamber and a nozzle.

An inkjet printing apparatus includes: a print head device including an inkjet head to spray a composition for ink including a plurality of bipolar elements; an ink circulation device including an ink storage to store the composition for ink, and transfer the composition for ink to the print head device; an ink injection device to inject the composition for ink into the ink storage; and a temperature adjusting device to adjust a temperature of the composition for ink. The temperature adjusting device includes: a first temperature adjusting device to adjust a temperature to be included in a first reference temperature range; a second temperature adjusting device to adjust a temperature to be included in a second reference temperature range; and a third temperature adjusting device to adjust a temperature to be included in a third reference temperature range.