A wafer structure is disclosed and includes a chip substrate and at least one inkjet chip. The chip substrate is a silicon substrate which is fabricated by a semiconductor process on a wafer of at least 12 inches. The at least one inkjet chip is directly formed on the chip substrate by the semiconductor process, and the wafer is diced into the at least one inkjet chip, to be implemented for inkjet printing.

A liquid ejecting head including: a first liquid ejecting portion configured to eject a liquid; a second liquid ejecting portion configured to eject a liquid; a first supply flow path configured to supply the liquid to the first liquid ejecting portion and the second liquid ejecting portion; and a temperature detection element for measuring a temperature of the liquid. The first supply flow path includes a common portion to which the liquid is supplied; a first branch portion that communicates with the common portion at a communication position, and that supplies the liquid from the common portion to the first liquid ejecting portion; and a second branch portion that communicates with the common portion at the communication position, and that supplies the liquid from the common portion to the second liquid ejecting portion. The temperature detection element is disposed at a vicinity of the communication position.

A liquid discharge head includes a recording element substrate including a discharge port. A channel member is configured to supply the recording element substrate with a liquid. An electric wiring board is configured to supply the recording element substrate with power. A plate-like protective member is directly or indirectly fixed to the channel member. In a case where a direction in which the recording element substrate is viewed from the channel member is defined as downward, the protective member includes a first bent portion configured to be bent in a transverse direction of the liquid discharge head. The first bent portion is located at a position that is above an upper end of the channel member and below a midpoint of a line segment connecting the upper end of the channel member and an upper end of the protective member.

Misalignment of printing positions is reduced in a print head that circulates an ink between a printing apparatus and the print head in a case where the misalignment is apt to change dynamically along with heat deformation. To this end, printing element substrates in the print head are adjusted to a target temperature and then a liquid is circulated through the print element substrates. After thermal expansion of the print head reaches a steady state, an amount of misalignment of printing positions in a direction of conveyance of the print head is obtained by using a test pattern printed by using printing elements. Further, a correction value for correcting the misalignment of the printing positions is set based on the obtained amount of misalignment of the printing positions.

Provided is a liquid ejection head comprising: an ejection opening row along a first direction; a pressure chamber with print-element; a passage communicating with the pressure chamber; a supply opening row along the first direction with supply openings extending in a second direction to supply liquid to the passage; a collection opening row along the first direction with collection openings extending in the second direction to collect a liquid from the passage; a first common supply passage along the first direction to supply a liquid to the supply opening row; a first common collection passage along the first direction to collect a liquid from the collection opening row; a first supply side communication opening extending in the second direction to supply a liquid to the first common supply passage; and a first collection side communication opening extending in the second direction to collect a liquid from the first common collection passage, wherein at least one of the first supply side communication opening and the first collection side communication opening is provided at a plurality of positions.

Provided is a liquid ejection head comprising a base plate and at least two device chips in which ejection ports for ejecting a liquid are formed and which are disposed on the base plate. At least one first reference mark is provided on the base plate. A second reference mark is provided on each of the device chips. At least one space is formed between adjacent ones of the device chips. The second reference marks and the first reference mark present in the space are disposed on an array axis along which the device chips are arrayed.

A fluid ejection device includes a fluid ejection die including a substrate and a fluid architecture supported by the substrate, and a molded body molded around the fluid ejection die, with the molded body interlocked with the fluid architecture of the fluid ejection die.

An ink-jet treatment liquid includes: an emulsified particle containing a silicone oil; and an aqueous medium. The silicone oil contains at least an ionic group-containing silicone oil, and content rate of the silicone oil in the ink-jet treatment liquid is 5% by mass or more and 15% by mass or less. Viscosity of the silicone oil is 1,000 mm.sup.2/s or more.

An inkjet head includes a first and a second channel substrates. At least one of the first and the second channel substrates is formed of silicon. A bonding interface of the first and the second channel substrates is bonded via an adhesive layer. A protective film containing a compound having a Si—C bond is formed on: an ink channel surface formed of silicon among the first and the second channel substrates; and a surface of the channel substrate side formed of silicon in the adhesive layer.

A liquid ejection head 2 in the present disclosure is provided with a first channel member 4 including a first surface 4-1, a plurality of ejection ports in the first surface, a plurality of pressurizing chambers which are individually communicated with the plurality of ejection ports, and a second surface 4-2 on the opposite side to the first surface 4-1; with a pressurizing member on the second surface 4-2; and with a second channel member 6 including a third surface 6-3, a fourth surface 6-4 on the opposite side to the third surface 6-3, a raised part 6e which protrudes from the fourth surface, and a first through hole 6a in the raised part 6e. The second channel member 6 is provided on a region in the second surface 4-2 of the first channel member 4, in which the pressurizing member is not arranged. When viewed on a plane, an outer circumference 7a of the raised part is located on inner side from an outer circumference 7b of the fourth surface 6-4.