A method for manufacturing a liquid ejection head includes selectively exposing a first photosensitive resin layer to light, thereby curing the portion of the first photosensitive resin layer defining a flow channel member; forming a second photosensitive resin layer on the first photosensitive resin layer; selectively exposing the second photosensitive resin layer to light, thereby curing the portion of the second photosensitive resin layer defining an ejection opening member; and removing the unexposed portions of the first and the second photosensitive resin layer at one time with a developer. Before removal with the developer, the water absorption W of the intermediate layer, the water absorption W1 of the exposed portion of the first photosensitive resin layer, and the water absorption W2 of the exposed portion of the second photosensitive resin layer satisfy the relationship WW1>W2.

A valve unit includes a flow path member having an opening surface that has a flow path opening of a liquid flow path, a valve having a sealing surface configured to seal the flow path opening, and a sealing member disposed on one of a peripheral portion of the flow path opening in the opening surface and a portion of the sealing surface facing the peripheral portion. The sealing surface is configured to be moved forward and backward relative to the opening surface to open and close the flow path opening. The sealing member is configured to be in contact with the peripheral portion of the flow path opening and the sealing surface when the valve is closed. The sealing member includes a fluorinated polyether.

There are provided a conductive base; a plurality of head main bodies which are held by the base and each have a switching element and a pressure generating element for discharging a liquid in a pressure generating chamber; a plurality of covers which are separated from the base, at least one of the pressure generating element and the switching element being sandwiched between the base and each of the covers; and a plurality of conduction portions which each conduct the base and the cover to each other at a plurality of locations.

A head chip, a liquid jet head, a liquid jet recording device, and a method of manufacturing a head chip each capable of suppressing the variation in ejection performance between the ejection channels without changing the shape of a channel (a drive wall) are provided. In the head chip according to an aspect of the present disclosure, when a region in which the first common electrode part and a second common electrode part are opposed in an X direction to each other across the drive wall, and which is configured to generate an electrical field in the drive wall is defined as an opposed region, a dimension in a Z direction in a first upside common part is formed so as to decrease in a direction from the drive wall located at the first side in the X direction toward the drive wall located at the second side in the X direction among the plurality of drive walls, a dimension in the Z direction in a second upside common part is formed so as to decrease in a direction from the drive wall located at the second side in the X direction toward the drive wall located at the first side in the X direction among the plurality of drive walls, and a dimension in a Y direction in the opposed region decreases in directions from the drive walls located at both end sides in the X direction toward the drive wall located in a central portion in the X direction.

There are provided a head chip, a liquid jet head, a liquid jet recording device, and a method of manufacturing a head chip each capable of ensuring an inter-electrode distance of each of channels while achieving narrowing of a pitch of the channels. In the head chip according to an aspect of the present disclosure, an electrical conducting material removal area in which laser irradiation scars are formed throughout an entire area in an X direction of a portion located between a lower end opening of an ejection channel and a lower end opening of a non-ejection channel is disposed in a portion located between the lower end opening of the ejection channel and the lower end opening of the non-ejection channel in a lower surface of an actuator plate.

A fluid ejection head for a fluid jet ejection device and a method for improving adhesion between a nozzle plate and a flow feature layer of the ejection head. The fluid ejection head includes a silicon substrate containing at least one array of fluid ejectors deposited thereon. At least one fluid supply via is etched through the silicon substrate adjacent to the at array of fluid ejectors. A flow feature layer is attached to the silicon substrate. The flow feature layer contains at fluid chambers and fluid flow channels corresponding the array of fluid ejectors for ejecting fluid provide fluid from the at least one fluid supply via to fluid chambers. At least a portion of the flow feature layer comprises an attachment surface having improved surface adhesion characteristics, and a nozzle plate containing nozzle holes is laminated to the flow feature layer to provide the fluid ejection head.

A liquid ejecting head with a sealing member includes: a liquid ejecting head including a liquid ejecting surface configured to eject ink; a fixing member configured to be attachable to and detachable from the liquid ejecting head; and a sealing member configured to seal the liquid ejecting head and the fixing member. When the liquid ejecting head to which the fixing member is joined is mounted on a cover, the sealing member seals the liquid ejecting head and the cover.

A method for manufacturing a flow path member includes bringing a flexible member into contact with a first substrate including a recessed portion via an adhesive agent so as to cover the recessed portion, wherein the flexible member is configured to suppress vibrations of a liquid in a flow path, curing the adhesive agent in a state where at least an area of the flexible member covering the recessed portion is supported by a support member, bonding a second substrate to a side of the first substrate with which the flexible member is brought into contact, wherein the second substrate is configured to form the flow path facing the flexible member, and removing the support member from the flexible member in a period after the curing and before the bonding.

The electrohydrodynamic print head comprises a nozzle carrier with a plurality of nozzles arranged thereon. A plurality of electrodes associated with the nozzles are located on the front side of the nozzles. A support structure supporting the electrodes is located on the nozzle carrier and comprises a plurality of support elements arranged between the nozzles. Ink retainers are arranged between the nozzles and the support elements. The front surfaces of the ink retainers are located behind the front ends of the nozzles in order to prevent the nozzles from being submerged by ink. Guard electrodes can be provided between the ejection electrodes and the ink retainers to reduce the electrical fields at the ink retainers and thereby to improve their efficiency to pin the ink. Suction ducts surrounding each nozzle allow to remove ink from the nozzles.

A manufacturing method of a liquid ejection unit includes: arranging an electric wiring board on a print element board such that the electric wiring board abuts the print element board, the print element board including an ejection port configured to eject liquid, an energy generating element configured to generate energy for ejecting the liquid from the ejection port, and an electrode pad electrically connected to the energy generating element, the electric wiring board including a terminal for electrical connection to the electrode pad; connecting the electrode pad and the terminal to each other by using an electric connection member; and covering an electric connection portion with a sealing agent, the electric connection portion including at least the electric connection member, the electrode pad, and the terminal, in which in the connecting, the electric connection member is shaped to include at least one bending point.