A method for manufacturing a printing bar unit for a printing system includes the steps of providing a support bar having a plurality of primary mounting positions, providing a plurality of exchangeable printheads having a plurality of inkjet nozzles, and releasably mounting the printheads to the support bar. Preceding the step of releasably mounting the printheads to the support bar, a plurality of reference organs are connected at the primary mounting positions to the support bar and undergo an alignment finishing process for forming a plurality of accurate secondary mounting positions, and then in a subsequent step the printheads are releasably mounted to the secondary mounting positions on the reference organs. A dimensional tolerance of the secondary mounting positions on the reference organs relative to each other is more accurate than a dimensional tolerance of the primary mounting positions on the support bar relative to each other.

To provide an ink jet recording method capable of suppressing generation of image streaks and recording a high-quality image, when using a recording apparatus equipped with a line head. Provided is an ink jet recording method which records an image on a recording medium by using an ink jet recording apparatus equipped with a line head. In this method, the line head has a plurality of recording element substrates each having a nozzle array made up of a plurality of nozzles which eject an aqueous ink. The recording element substrates are arranged in the predetermined direction. An average temperature Te (° C.) of an aqueous ink ejected from terminal-portion nozzles constituting the terminal portion of the nozzle array and an average temperature Tc (° C.) of an aqueous ink ejected from center-portion nozzles constituting the center portion of the nozzle array satisfy the following relationship: Te>Tc.

To provide an ink jet recording method capable of suppressing generation of image streaks and recording a high-quality image, when using a recording apparatus equipped with a line head. Provided is an ink jet recording method which records an image on a recording medium by using an ink jet recording apparatus equipped with a line head. In this method, the line head has a plurality of recording element substrates each having a nozzle array made up of a plurality of nozzles which eject an aqueous ink. The recording element substrates are arranged in the predetermined direction. An average temperature Te (° C.) of an aqueous ink ejected from terminal-portion nozzles constituting the terminal portion of the nozzle array and an average temperature Tc (° C.) of an aqueous ink ejected from center-portion nozzles constituting the center portion of the nozzle array satisfy the following relationship: Te>Tc.

A liquid ejection head, including: a first head unit; a second head unit shifted with respect to the first head unit in both of a first direction in which nozzles of the head units are arranged and a second direction orthogonal to the first direction and disposed so as to overlap the first head unit in the second direction; and a first wiring member having flexibility and drawn from the second head unit in the second direction toward the first head unit, wherein the first wiring member includes a large-width portion on which a drive circuit is mounted and a small-width portion having a width in the first direction smaller than a width of the large-width portion in the first direction, and wherein the small-width portion passes through a space existing next to the first head unit in the first direction and extends in the second direction.

A liquid ejection head, including: a first head unit; a second head unit shifted with respect to the first head unit in both of a first direction in which nozzles of the head units are arranged and a second direction orthogonal to the first direction and disposed so as to overlap the first head unit in the second direction; and a first wiring member having flexibility and drawn from the second head unit in the second direction toward the first head unit, wherein the first wiring member includes a large-width portion on which a drive circuit is mounted and a small-width portion having a width in the first direction smaller than a width of the large-width portion in the first direction, and wherein the small-width portion passes through a space existing next to the first head unit in the first direction and extends in the second direction.

A plurality of element arrays are formed between a first terminal array and a second terminal array by a plurality of elements. An element array positioned closer to the second terminal array than to the first terminal array is connected to the second terminal array. An element array positioned closer to the first terminal array than to the second terminal array is connected to the first terminal array.

A plurality of element arrays are formed between a first terminal array and a second terminal array by a plurality of elements. An element array positioned closer to the second terminal array than to the first terminal array is connected to the second terminal array. An element array positioned closer to the first terminal array than to the second terminal array is connected to the first terminal array.

A liquid discharge head includes a recording element board including a discharge port for discharging liquid, a channel member including a channel for supplying the liquid to the recording element board, and supporting the recording element board, a first supporting portion fixed to the channel member on one end side of the channel member in a longitudinal direction, and a second supporting portion fixed to the channel member on another end side of the channel member in the longitudinal direction, and a first member supported by the first supporting portion and the second supporting portion. The first supporting portion supports the first member in such a manner that the first member is movable in the longitudinal direction relative to the first supporting portion.

A liquid discharge device to perform recording by use of a liquid discharge head including discharge ports to discharge a liquid, pressure generation elements to generate energy to be used to discharge the liquid, and pressure chambers communicating with the discharge ports. The liquid discharge device includes: a control unit to control a temperature of the liquid discharge head by applying heat with heating elements arranged in divided areas of a region of the liquid discharge head where the discharge ports are arranged. When there is recording data for the discharge port in a certain one of the divided areas, the control unit causes the heating element in the divided area to generate heat, and when there is no recording data for the discharge port in the certain divided area, the control unit keeps the heating element in the certain divided area from generating heat.

There is provided a liquid ejecting head which is long in a first direction and short in a second direction, including: a first introduction section; a second introduction section; a first filter chamber group having a first filter chamber and a second filter chamber; a second filter chamber group having a third filter chamber and a fourth filter chamber; a first supply flow path for supplying the liquid from the first introduction section to the first filter chamber group; and a second supply flow path for supplying the liquid from the second introduction section to the second filter chamber group, in which the first introduction section, the second introduction section, the first filter chamber group, and the second filter chamber group are arranged side by side in this order in the first direction.