A liquid ejecting unit includes: a liquid ejecting head configured to eject a liquid; a holding portion holding the liquid ejecting head; a coupling member; and a first fixing member fixing the liquid ejecting head to the holding portion, in which the coupling member is provided with a first coupling portion and a first through-hole, the liquid ejecting head is provided with a second coupling portion that is configured to be coupled to the first coupling portion, and the first fixing member passes through the first through-hole in a state in which the first coupling portion and the second coupling portion are coupled to each other.

An object of the present invention is to provide a liquid droplet ejection head and a liquid droplet ejection apparatus in which viscosity resistance of a liquid to be ejected is reduced on an ejection side of a nozzle to prevent pointed-end ejection and to improve accuracy of an ejection angle. This object is achieved by the following. That is, a channel 28 having a volume to be changed by a pressure generation element and a nozzle 23 communicating with the channel 28 are included. The inside of the nozzle 23 has a conical portion 23a with a diameter becoming gradually smaller toward an outside, and a cylindrical portion 23b continuous with the conical portion 23a and communicating with the outside. A connecting part of the conical portion 23a to the cylindrical portion 23b has the same opening cross-sectional shape as a connecting part of the cylindrical portion 23b to the conical portion 23a. When an inner diameter of the cylindrical portion 23b is represented by D.sub.0, the cylindrical portion 23b has an axial length of 0.1D.sub.0 to 0.3D.sub.0, and the conical portion 23a has an axial length of 0.6D.sub.0 or more and a conical surface in which a generating line has an angle of 6 degrees or more and 15 degrees or less with respect to a nozzle central axis.

To manufacture a liquid ejection head, a film having a lower surface free energy than a surface free energy of a substrate is first formed on an inner face of a liquid supply port. Next, a dry film to be a flow path forming member is attached to cover the surface of the substrate, and then a member to be an ejection orifice forming member is provided on the surface of the dry film.

A liquid ejection head is equipped with a substrate having therethrough a supply path to be supplied with a liquid, a top plate placed opposite to the substrate, having an ejection orifice for ejecting the liquid and constituting, between the top plate and the substrate, a flow path communicated with the supply path and the ejection orifice and a columnar member extending from the top plate to the inside of the supply path through the flow path. An end surface of the columnar member positioned in the supply path is tilted relative to the top plate in a direction away from the ejection orifice.

A liquid-discharge-head substrate includes a first covering portion covering a first heating resistance element and having electrical conductivity, a second covering portion covering a second heating resistance element and having electrical conductivity, a fuse, and a common wiring line for electrically connecting the first and second covering portions. The common wiring line is electrically connected with the first covering portion via the fuse. The common wiring line and the fuse each have a multilayer structure including a stack of a plurality of conductive layers including a first conductive layer and a second conductive layer that is less oxidizable than the first conductive layer.

A liquid discharge head includes a head substrate and a surface treatment film on a surface of the head substrate. The surface treatment film is an oxide film containing Si. The oxide film contains a transition metal to form a passive film. A content of Si in a vicinity of an interface of the surface treatment film with the head substrate is higher than a content of Si in an inside of the surface treatment film and is 20 at % or more.

A liquid ejecting head includes a driving substrate including a driving element configured to, in response to a signal from an external controller, expand or contract so that a liquid is discharged from a pressure chamber through a nozzle, and a connection portion connecting the driving element to a wiring substrate connectable to the external controller; a sealing member that covers the connection portion and a part of the wiring substrate; and a mask plate partially covering a part of the driving substrate including the connection portion and contacting the sealing member.

A head module includes a base including a plurality of openings, and a plurality of heads inserted into the plurality of openings, respectively, to be mounted on the base. The plurality of heads includes a nozzle plate including a nozzle, an individual channel member disposed on the nozzle plate and including an individual chamber communicating with the nozzle, and a frame fixed to the individual channel member. Coefficients of linear expansion of the nozzle plate and the individual channel member are substantially identical to a coefficient of linear expansion of the base, and one of the nozzle plate and the individual channel member is bonded to the base.

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.

Provided herein are a jet hole plate, a liquid jet head, and a liquid jet recording apparatus that can achieve a long life. A jet hole plate according to an embodiment of the present disclosure is a jet hole plate for use in a liquid jet head. The jet hole plate includes a metal substrate provided with a plurality of jet holes. In the metal substrate, an average crystal grain size in outlet edges of the jet holes is smaller than that in surrounding regions around the outlet edges.