A head includes: an attachment attached to a holder with a screw, the attachment having a through hole to which the screw is inserted, and the through hole having: a female screw having a valley and a crest; and a first concave having a diameter larger than a diameter of the valley of the female screw, the first concave opening toward the holder.

A liquid ejecting head includes an introduction portion for introducing a gas supplied, a discharge portion for discharging the gas, and drive circuits provided in each of head chips, in which the drive circuits include a first drive circuit for driving the first head chip and a second drive circuit for driving the second head chip, a gas path through which the gas flows from the introduction portion to the discharge portion includes a first path coupled to the introduction portion, a second path coupled to the discharge portion, a first branch path coupling the first path and the second path, and a second branch path coupling the first path and the second path so as not to pass through the first branch path, the first drive circuit is disposed in the first branch path, and the second drive circuit is disposed in the second branch path.

A liquid discharge head includes a nozzle from which a liquid is dischargeable in a liquid discharge direction, an individual chamber communicating with the nozzle, a common chamber configured to store the liquid to be supplied to the individual chamber, a pressure generator configured to apply pressure to the liquid in the individual chamber, a holder holding the pressure generator, a first temperature detector adjacent to the common chamber, the first temperature detector configured to detect temperature proximate to the common chamber, and a second temperature detector held by the holder, the second temperature detector configured to detect temperature of the holder.

A liquid discharge head is provided which comprises a head body, a casing and a thermal insulator. The head body comprises a surface having one or more holes configured to discharge liquids therethrough. The casing, disposed on the head body, comprises a heat generator configured to generate heat and a heat sink configured to dissipate the heat. The thermal insulator is between the heat sink and the head body.

There is provided a liquid discharge head including: a communication plate having a plurality of descenders in respective communication with a plurality of nozzles, a pressure chamber plate being stacked on the communication plate and having a plurality of pressure chambers, a piezoelectric element arranged in a position overlapping with the pressure chambers in a stacking direction, and a discharge common channel extending in an array direction and being in communication with the plurality of pressure chambers. The discharge common channel includes: a first discharge portion formed in the communication plate; and a second discharge portion formed in the pressure chamber plate and in communication with the first discharge portion, the second discharge portion reaching as high as to a surface of the pressure chambers at the side of the piezoelectric element along the stacking direction.

A liquid discharge head includes a head body, a driver IC, a housing, a heat dissipation plate, and a pressing member. The head body includes a discharge hole configured to discharge a liquid. The driver IC controls driving of the head body. The housing is located on the head body, and includes an opening at a side surface. The heat dissipation plate is located at the opening of the housing, and is configured to dissipate heat generated by the driver IC. The pressing member presses the driver IC against the heat dissipation plate. In addition, the heat dissipation plate is fixed to the pressing member.

A method for processing water-based low-viscosity liquid inkjet inks for digital, contactless inkjet printing, wherein the inkjet ink is applied from systematically arranged nozzles in a time-dependent and location-dependent manner and divided into individual volume units, characterized in that the inkjet ink at the nozzle outlet is or is being cooled to temperatures below the temperature of the ambient air. A device for processing water-based low-viscosity liquid inkjet inks for digital, contactless inkjet printing, comprising at least one print head, whereby inkjet inks are applicable from systematically arranged nozzles in a time-dependent and location-dependent manner and divided into individual volume units, characterized in that the print head and/or the inkjet ink supplied to the print head is coolable.

A stress caused in an actuator member with respect to input or output of heat is reduced. There is provided a liquid jet head including an actuator member having a pressure chamber, a low rigidity support part which is disposed at one side with respect to the actuator member, and is coupled to the actuator member, and a high rigidity support part which is disposed at the other side opposite to the one side with respect to the actuator member, and is coupled to the actuator member. The high rigidity support part has a high rigidity part which includes a head constituent member of the liquid jet head higher in linear expansion coefficient and Young's modulus than the actuator member, and which reduces a thermal deformation of the high rigidity support part in a direction of extension or contraction of the actuator member with respect to input or output of heat to or from the liquid jet head to be smaller than a thermal deformation exhibited in the direction of the extension or the contraction by the head constituent member with respect to the input or the output of the heat. The low rigidity support part is lower in rigidity in the direction of the extension or the contraction than the actuator member.

A liquid ejection head includes a supply channel structure and a heater. The supply channel structure has a supply channel configured to allow liquid to flow therefrom to ejection channels that are configured to lead liquid to nozzles aligned in a first direction. The heater is configured to heat liquid. Assuming that a side of the liquid ejection head, in which the nozzles are provided, is defined as a lower side of the liquid ejection head, the heater is disposed above the supply channel structure.

A liquid ejecting head includes piezoelectric elements for ejecting liquid from nozzles, pressure chambers in communication with the nozzles, individual supply flow passages for supplying the liquid to the nozzles, individual collection flow passages for collecting the liquid not ejected from the nozzles, a diaphragm that defines a wall surface of the pressure chambers and deforms by driving the piezoelectric element, a flexible substrate having a drive circuit electrically coupled to the piezoelectric elements, and a heat release member that is either in contact with an surface of the flexible substrate that faces away from the drive circuit, or in contact with the drive circuit, and conducts heat of the drive circuit to the diaphragm. The heat release member is disposed closer to the individual supply flow passage than to the individual collection flow passage.