JP2020110957A - Ink jet head, ink jet device, and manufacturing method of ink jet head - Google Patents

Abstract

To provide an ink jet head allowing for securement of ink ejection performance and pressure resistance, and to provide an ink jet device and a manufacturing method of an ink jet head.SOLUTION: The ink jet head according to one embodiment comprises: a nozzle plate 30 and an actuator base. The nozzle plate has a plurality of nozzles 31. The actuator base has a plurality of wall portions 25, a plurality of first grooves 23a, and a plurality of second grooves 23b. The wall portions each have joint surfaces 25c joined to the nozzle plate. First grooves each are disposed on one side of the corresponding wall portion and form a pressure chamber C1 communicating with the plurality nozzles. The second grooves each are disposed on the other side of the corresponding wall portion. A nozzle plate and an actuator base are joined together via an adhesive 50 between the joint surfaces of the plurality of wall portions and the nozzle plate. In more than a half of the plurality of wall portions, the adhesive is disposed on the second groove side rather than on the first groove side.SELECTED DRAWING: Figure 4

Description

Embodiments of the present invention relate to an inkjet head, an inkjet device, and a method for manufacturing an inkjet head.

In a share mode shared wall type inkjet head including a plurality of pressure chambers, a plurality of pressure chambers communicating with the nozzles and a plurality of air chambers arranged between the plurality of pressure chambers are alternately provided in a predetermined parallel direction. The composition is known. In such a liquid ejection head, a nozzle plate is joined to an actuator base having a plurality of grooves forming pressure chambers and air chambers by, for example, an adhesive.

JP, 2010-131939, A

In such an ink jet head, it is difficult to control the application position of the adhesive, and the ink may protrude into the pressure chamber. If the adhesive that has run off is applied to the nozzles, it adversely affects the ejection performance of the ink droplets and causes deterioration of print quality. On the other hand, if the application amount of the adhesive is reduced in order to prevent the adhesive from squeezing out, the pressure resistance is impaired due to insufficient bonding strength.

The problem to be solved by the present invention is to provide an inkjet head, an inkjet device, and a method of manufacturing an inkjet head, which can ensure ejection performance and pressure resistance.

An inkjet head according to one embodiment includes a nozzle plate and an actuator base. The nozzle plate has a plurality of nozzles. The actuator base has a plurality of walls, a plurality of first grooves, and a plurality of second grooves. The wall portion has a joint surface joined to the nozzle plate. The first groove forms a pressure chamber which is arranged on one side of the wall portion and communicates with the plurality of nozzles. The second groove is arranged on the other side of the wall portion. The nozzle plate and the actuator base are joined to each other via an adhesive agent between the joining surfaces of the plurality of walls and the nozzle plate. In the majority of the wall portions of the plurality of wall portions, the adhesive is distributed more toward the second groove side than on the first groove side.

FIG. 3 is an exploded perspective view showing the configuration of the inkjet head according to the first embodiment. FIG. 3 is a perspective view showing the configuration of part of the inkjet head. Sectional drawing which shows the structure of some inkjet heads. Explanatory drawing which shows the manufacturing method of the same inkjet head. Explanatory drawing which shows the structure of the inkjet printer using the same inkjet head. FIG. 6 is an explanatory view showing a method of manufacturing an inkjet head according to another embodiment.

An inkjet head 1 which is a liquid ejection head and an inkjet printer 100 which is an inkjet device according to the first embodiment will be described below with reference to FIGS. 1 to 5. In each drawing, for convenience of explanation, the configuration is enlarged, reduced, or omitted. Arrows X, Y, Z in the figure indicate three directions orthogonal to each other. In the present embodiment, an example is shown in which the first direction of the inkjet head 1 is arranged along the X axis, the second direction is arranged along the Y axis, and the third direction is arranged along the Z axis.

FIG. 1 is an exploded perspective view showing a part of the inkjet head 1 according to the first embodiment, FIG. 2 is a perspective view showing a part of the configuration of the inkjet head 1, and FIG. 3 is a part of the inkjet head 1. FIG.

The inkjet head 1 shown in FIGS. 1 to 6 is a liquid ejection head and includes an actuator base 20, a nozzle plate 30, and a frame 40. The inkjet head 1 is a share mode shared wall type inkjet head.

The actuator base 20 includes a substrate 21 and a laminated piezoelectric body 22. The actuator base 20 is joined to face the nozzle plate 30 with the frame 40 sandwiched therebetween, and forms a common chamber C3 with the nozzle plate 30.

The substrate 21 has a rectangular plate shape. The substrate 21 is preferably made of PZT, ceramics, glass, free-cutting ceramics, or a material containing these. The substrate 21 has a plurality of supply holes 21a and recovery holes 21b, which are through holes penetrating in the thickness direction.

The laminated piezoelectric body 22 is formed on the surface of the substrate 21 on the nozzle plate 30 side. In the present embodiment, two laminated piezoelectric bodies 22 extending along a predetermined first direction are arranged in parallel on the main surface of the substrate 21. The laminated piezoelectric body 22 is configured by laminating two piezoelectric members. The piezoelectric member is made of, for example, a PZT (lead zirconate titanate)-based piezoelectric ceramic material. Besides, lead-free piezoelectric ceramics such as KNN (potassium sodium niobate) may be used as the piezoelectric member in consideration of the environment. The two piezoelectric members are polarized so that their polarization directions are opposite to each other, and are bonded via an adhesive layer.

A groove row 23A having a plurality of grooves 23 arranged in the first direction is formed on an end surface of the laminated piezoelectric body 22 facing the nozzle plate 30. The cross-sectional shape of the laminated piezoelectric body 22 along the first direction and the third direction is a comb tooth shape. A pillar-shaped partition wall portion 25 formed of a piezoelectric element is formed between the adjacent grooves 23. The partition wall portion 25 serves as a drive element that changes the volume of the groove 23.

In the groove row 23A, a plurality of first grooves 23a and a plurality of second grooves 23b are alternately arranged in the first direction. The plurality of grooves 23 are arranged in parallel in the first direction, extend in the second direction, and are arranged in parallel with each other. The grooves 23a and 23b are formed over the entire length of the laminated piezoelectric body 22 in the second direction. That is, the grooves 23a and 23b open on the nozzle plate 30 side. Electrodes 24 are formed on the inner bottom surface and both side surfaces of each of the grooves 23a and 23b.

Both ends of the first groove 23a in the second direction open in the opening 41a of the frame member 41 and communicate with the common chamber C3. The first grooves 23a are provided at the positions facing the nozzles 31, respectively, and the same number as the nozzles 31 is provided. The first groove 23a constitutes a pressure chamber C1 that communicates with the common chamber C3 and the nozzle 31.

At both ends of the second groove 23b in the second direction, cover walls 27 made of a photocurable resin are provided. The cover wall 27 closes both ends of the second groove 23b in the second direction. The second groove 23b is closed by a cover wall 27 that covers both ends in the second direction, a nozzle plate 30 that covers the third direction, and partition walls 25 arranged on both sides in the first direction, and the pressure chamber C1 and the common chamber C3. To form an air chamber C2 separated from.

The partition wall portion 25 is, for example, a rectangular parallelepiped wall-shaped member that is arranged between the plurality of grooves 23 and extends along the second direction. The partition wall portion 25 is composed of a piezoelectric element in which a first piezoelectric element 25a and a second piezoelectric element 25b laminated on the first piezoelectric element 25a are laminated. A joint surface 25c, which is an end surface of the partition wall portion 25 on the nozzle plate 30 side, is joined to the nozzle plate 30 via an adhesive 50. By bonding the joint surface 25c of the partition wall portion 25 to the nozzle plate 30, the air chamber C2 formed by the second groove 23b is closed.

As the adhesive 50, for example, an epoxy adhesive effective for ink resistance is used. For example, in this embodiment, an adhesive of the type that is heated to 80° C. during curing is used. The adhesive 50 is biased closer to the second groove 23b arranged on the other side than the first groove 23a arranged on the one side of the partition wall 25.

In the inkjet head 1, the position of the adhesive 50 between the partition walls 25 facing each other in the majority of the nozzles 31 (80% or more, for example) is closer to the second groove 23b side than the center of the partition wall 25. The edge of the application area of the adhesive 50 on the side of the first groove 23a is retracted without protruding from the edge of the partition wall 25. The amount of adhesive 50 applied is not uniform, and the amount applied on the second groove 23b side is large. The amount of protrusion of the adhesive 50 from the joining surface 25c of the partition wall portion 25 to the groove side is larger on the second groove 23b side than on the first groove 23a side.

As an example, in the present embodiment, in the partition wall portion 25 between the pressure chamber C1 facing 80% or more of the nozzles 31 among the plurality of nozzles 31 and the air chamber C2 adjacent thereto, the application area of the adhesive 50. Is closer to the second groove 23b than the center of the partition wall 25, and has a positional relationship that does not protrude into the first groove 23a.

Here, as an example of a manufacturing process of the inkjet head 1, a method of biasing the adhesive 50 to the second groove 23b side and joining the actuator base 20 and the nozzle plate 30 will be described. In the manufacturing process of the inkjet head 1, the bonding process for bonding the actuator base 20 and the nozzle plate 30 includes a coating process of coating the adhesive 50 on the bonding surface 25c of the partition wall 25, and an actuator base 20 after the coating of the adhesive 50. And a curing step of curing the adhesive 50.

In the present embodiment, as an example, as shown in FIG. 4, for example, in the coating process of applying the adhesive 50 to the bonding surface 25c, the adhesive 50 is applied to the bonding surface 25c of the partition wall portion 25 on the second groove side. Apply to the position. As a specific example, for example, the center of the application area of the adhesive 50 is arranged at a position closer to the second groove 23b than the center of the joint surface 25c. In the present embodiment, the coating is applied to a half region closer to the second groove than the center. As described above, by applying the adhesive while shifting the application position, the inkjet head 1 is formed in which the position of the adhesive 50 is biased.

The electrode 24 is a conductive film made of a conductive material such as nickel. The electrode 24 is formed on the bottom of the first groove 23 a and is connected to the wiring pattern 26 on the substrate 21. The electrode 24 is formed by a method such as a vacuum deposition method or an electroless nickel plating method. The electrode 24 may be formed of gold or copper, for example. Alternatively, two or more kinds of conductive films may be laminated.

The wiring pattern 26 (wiring electrode) is, for example, a conductive film formed of a conductive material such as nickel similar to the electrode 24 and having a predetermined pattern shape. The wiring pattern 26 is formed on the main surface of the substrate 21. The wiring pattern 26 is formed at the same time when the electrode 24 is formed by a method such as a vacuum deposition method or an electroless plating method. The wiring pattern 26 is formed so as to extend to the outside of the frame member 41, and the drive circuit can be connected by an FPC or the like at the portion exposed to the outside of the frame member 41.

A manifold that forms a predetermined ink flow path is connected to the surface of the actuator base 20 opposite to the nozzle plate 30. The manifold includes a supply path that is a flow path that communicates with the common chamber C3 and a supply flow path 133a, and a recovery path that communicates with the common chamber C3 and a recovery flow path 133b. For example, a circuit board on which a driving IC is mounted is provided on the outer surface of the manifold, and the driving IC is electrically connected to the electrode 24 via an FPC (Flexible Printed Circuits) and a wiring pattern.

The nozzle plate 30 is made of a resin material such as a polyimide film and has a rectangular plate shape. A plurality of nozzles 31 penetrating in the thickness direction is formed on the nozzle plate 30. The plurality of nozzles 31 communicate with each pressure chamber C1. In this embodiment, the nozzles 31 are arranged in two rows, and 600 nozzles 31 are arranged in parallel in each row. The nozzle plate 30 is disposed so as to face the actuator base 20, covers the groove array 23A on the substrate 21 to close the opening of the second groove 23b, and the pressure chamber C1 configured by the first groove 23a is formed by the nozzle. Connect to 31.

The frame 40 is configured in a rectangular frame shape, and includes a frame member 41 that forms a rectangular opening 41a in the center. The frame member 41 has a predetermined thickness and is arranged between the actuator base 20 and the nozzle plate 30 to communicate with the first groove 23a of the actuator base 20 arranged in the opening 41a. Form C3.

In the inkjet head 1 configured as described above, in a state where the actuator base 20, the nozzle plate 30, and the frame 40 are assembled, the plurality of pressure chambers C1 communicating with the nozzles 31 are formed in the opening 41a of the frame member 41. A plurality of air chambers C2 closed by the nozzle plate 30 and the cover wall 27 and a common chamber C3 communicating with the plurality of pressure chambers C1 are formed. The pressure chambers C1 and the air chambers C2 are arranged alternately in the first direction and are partitioned by the partition wall portion 25 formed of a piezoelectric element.

Next, an inkjet printer 100 having the inkjet head 1 will be described with reference to FIG. FIG. 5 is an explanatory diagram showing the configuration of the inkjet printer 100. As shown in FIG. 5, the inkjet printer 100 includes a housing 111, a medium supply unit 112, an image forming unit 113, a medium discharge unit 114, a conveyance device 115, and a control unit 116.

The inkjet printer 100 conveys, for example, paper P as a recording medium as an ejection target while conveying a paper P as a recording medium as an ejection target along a predetermined conveyance path A1 from the medium supply unit 112 to the medium discharge unit 114 through the image forming unit 113. The liquid ejecting apparatus performs an image forming process on the paper P by ejecting the liquid.

The medium supply unit 112 includes a plurality of paper feed cassettes 112a. The medium ejection unit 114 includes a paper ejection tray 114a. The image forming unit 113 includes a support unit 117 that supports a sheet, and a plurality of head units 130 that are disposed above the support unit 117 and face each other.

The support unit 117 includes a conveyor belt 118 that is provided in a loop in a predetermined area for forming an image, a support plate 119 that supports the conveyor belt 118 from the back side, and a plurality of belt rollers 120 that are provided on the back side of the conveyor belt 118. , Is provided.

The head unit 130 includes a plurality of inkjet heads 1, a plurality of ink tanks 132 as liquid tanks mounted on the inkjet heads 1, and a connection channel 133 that connects the inkjet head 1 and the ink tank 132. And a circulation pump 134 which is a circulation unit. The head unit 130 is a circulation type head unit that circulates a liquid.

In the present embodiment, as the inkjet head 1, inkjet heads 1C, 1M, 1Y, and 1B of four colors of cyan, magenta, yellow, and black, and ink tanks 132C and 132M that store inks of these colors, respectively. , 132Y, 132B. The ink tank 132 is connected to the inkjet head 1 by a connection channel 133. The connection flow path 133 includes a supply flow path 133a connected to the supply port of the inkjet head 1 and a recovery flow path 133b connected to the discharge port of the inkjet head 1.

A negative pressure control device such as a pump (not shown) is connected to the ink tank 132. Then, by controlling the negative pressure inside the ink tank 132 by the negative pressure control device in accordance with the water head pressure between the inkjet head 1 and the ink tank 132, the ink supplied to each nozzle of the inkjet head 1 has a predetermined shape. It is formed on the meniscus.

The circulation pump 134 is a liquid feed pump including, for example, a piezoelectric pump. The circulation pump 134 is provided in the supply flow path 133a. The circulation pump 134 is connected to the drive circuit of the control unit 116 by wiring. A CPU (Central Processing Unit) 116a is configured to control the circulation pump 134. The circulation pump 134 circulates the liquid in a circulation flow path including the inkjet head 1 and the ink tank 132.

The transport device 115 transports the paper P along the transport path A1 from the paper feed cassette 112a of the medium supply unit 112 to the image discharge tray 114a of the medium discharge unit 114 through the image forming unit 113. The transport device 115 includes a plurality of guide plate pairs 121a to 121h arranged along the transport path A1 and a plurality of transport rollers 122a to 122h.

The control unit 116 includes a CPU 116a that is a controller, a ROM (Read Only Memory) that stores various programs, a RAM (Random Access Memory) that temporarily stores various variable data and image data, and the like from the outside. And an interface unit for inputting data and outputting data to the outside.

In the inkjet head 1 and the inkjet printer 100, at the time of driving to eject the liquid from the nozzle 31, the control unit 116 applies a drive voltage via the wiring pattern 26 by the drive circuit. When a potential difference is applied to the electrode in the pressure chamber C1 driven by the application of a voltage and the electrodes in the air chambers C2 adjacent to each other, the first piezoelectric element 25a and the second piezoelectric element 25b are deformed in opposite directions, and both piezoelectric elements are deformed. The driving element is bent and deformed by the deformation of the element. For example, first, the ink is guided into the pressure chamber C1 by deforming the pressure chamber C1 to be driven in the opening direction to make the inside of the pressure chamber C1 a negative pressure. Subsequently, the pressure chamber C1 is deformed in the closing direction, and the pressure in the pressure chamber C1 is increased to eject ink droplets from the nozzles 31.

The operation of the inkjet head 1 and the inkjet printer 100 configured as described above will be described. The control unit 116 detects a print instruction based on, for example, a user's operation input or an instruction from the outside. When the print instruction is detected, the control unit 116 drives the transport device 115 to transport the paper P and outputs a print signal to the head unit 130 at a predetermined timing to drive the inkjet head 1. To do. As an ejection operation, the inkjet head 1 selectively drives a piezoelectric element in accordance with an image signal corresponding to image data to eject ink from the nozzle 31 to form an image on the paper P held on the conveyor belt 118. ..

As a liquid discharge operation, the CPU 116a deforms the laminated piezoelectric body 22 by applying a driving voltage to the electrode 24 on the laminated piezoelectric body 22 via the wiring pattern 26 by the driving circuit. For example, the ink is guided into the pressure chamber C1 by deforming the pressure chamber C1 to be driven in a direction of increasing the volume and making the pressure chamber C1 negative pressure. On the other hand, by deforming the pressure chamber C1 in a direction in which the volume decreases and pressurizing the inside of the pressure chamber C1, an ink droplet is ejected from the nozzle 31. Due to the change in the volume of the pressure chamber C1, the droplet Id is ejected from the pair of nozzles 31 that are arranged to face the pressure chamber C1. Then, the liquid droplet Id is ejected onto the paper P that is arranged to face it.

According to the inkjet head 1 and the inkjet printer 100 according to the present embodiment, it is possible to provide an inkjet head, an inkjet device, and a method for manufacturing an inkjet head that can ensure ejection performance and pressure resistance. That is, by biasing the adhesive 50 to the dummy air chamber C2 that does not communicate with the nozzle 31, a required amount of the adhesive 50 can be applied, and high pressure resistance can be ensured by ensuring high adhesive strength. At the same time, the adhesive 50 can be prevented from entering the pressure chamber C1 side, and the influence on the liquid ejection performance can be avoided. Moreover, since it can be realized only by changing the coating position, the existing manufacturing apparatus and manufacturing process can be used.

It should be noted that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements within a range not departing from the gist of the invention in an implementation stage.

In the above-described first embodiment, an example in which the application area is adjusted in the application process of applying the adhesive 50 to the bonding surface 25c has been described as an example, but the present invention is not limited to this. For example, as another embodiment, as shown in FIG. 6, the position of the adhesive is controlled by providing a pressure difference between the first groove 23a and the second groove 23b in the curing step after the sticking process. Good. Specifically, in the manufacturing process of the inkjet head 1, the bonding process for bonding the actuator base 20 and the nozzle plate 30 includes a coating process of applying an adhesive to the bonding surface 25c of the partition wall portion 25 and a coating process after applying the adhesive. A step of attaching the nozzle plate 30 to the actuator base 20 and a step of curing the adhesive are provided.

In the present embodiment, as the adhesive 50, an epoxy-based adhesive that is effective in ink resistance and is of a type that is heated to 80° C. during curing is used. In the present embodiment, the adhesive 50 is applied to the joint surface 25c, the nozzle plate 30 is attached to the partition wall 25 and assembled, and then, when the assembled parts are heated and hardened, they are put in a pressure heating chamber. .. That is, the pressure in the closed air chamber C2 is made lower than the pressure in the pressure chamber C1 communicating with the outside by exposing each assembly component to a high-pressure environment. Therefore, before the adhesive 50 is completely cured, the adhesive 50 flows toward the air chamber C2 side where the pressure is low, and the position of the adhesive 50 is biased. For example, in the coating process, the adhesive can be biased by the pressure difference even when the adhesive is applied to the center of the joint surface 25c of the partition wall portion 25. In this embodiment, as in the first embodiment, the adhesive can be prevented from entering the first groove 23a, that is, the pressure chamber C1 side, and the pressure resistance and the ejection performance can be secured. Further, a pressure difference can be generated between the pressure chamber C1 and the air chamber C2 only by inserting the assembly parts into the pressure chamber, and the area of the adhesive can be easily controlled.

Further, in the above-described embodiment, the actuator base 20 including the laminated piezoelectric body 22 made of the piezoelectric member on the substrate 21 is exemplified, but the present invention is not limited to this. For example, the actuator base 20 may be formed only by the piezoelectric member without using the substrate 21. Further, instead of using two piezoelectric members, one piezoelectric member may be used.

The liquid to be ejected is not limited to ink, and liquids other than ink can be ejected. The liquid ejecting device that ejects a liquid other than ink may be, for example, a device that ejects a liquid containing conductive particles for forming a wiring pattern of a printed wiring board.

In addition to the above, the inkjet head 1 may have, for example, a structure in which a vibrating plate is deformed to eject ink drops, or a structure in which thermal energy of a heater or the like is used to eject ink drops from nozzles.

The inkjet head 1 has exemplified the configuration in which every other pressure chamber C1 is arranged, but the configuration is not limited to this. For example, two or more dummy air chambers C2 may be arranged between the pair of pressure chambers C1 and C1. Even in this case, the adhesive 50 of the partition wall portion 25 between the pressure chambers C1 and C2 may be provided. The liquid ejection performance of the nozzle can be maintained while ensuring the adhesive strength and the pressure resistance by arranging the position of (1) to the air chamber C2 side.

Further, in the above embodiment, an example in which the liquid ejection device is used in an inkjet recording device has been shown, but the liquid ejection device is not limited to this. For example, it can be used for 3D printers, industrial manufacturing machines, medical applications, and can be reduced in size and weight and cost.

According to at least one embodiment described above, it is possible to provide an inkjet head, an inkjet device, and a method for manufacturing an inkjet head that can ensure ejection performance and pressure resistance.

In addition, although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the scope of equivalents thereof.

1 (1C, 1M, 1Y, 1B)... Inkjet head, 20... Actuator base, 21... Substrate, 21a... Supply hole, 21b... Recovery hole, 22... Laminated piezoelectric body, 23... Groove, 23A... Groove row, 23a... 1st groove, 23b... 2nd groove, 24... Electrode, 25... Partition part (wall part), 25a... 1st piezoelectric element, 25b... 2nd piezoelectric element, 25c... Bonding surface, 26... Wiring pattern , 27... Cover wall, 30... Nozzle plate, 31... Nozzle, 40... Frame, 41... Frame member, 41a... Opening part, 50... Adhesive agent, 100... Inkjet printer, 111... Housing, 112... Medium supply section, 112a... Paper feed cassette, 113... Image forming unit, 114... Medium ejecting unit, 114a... Ejection tray, 115... Conveying device, 116... Control unit, 116a... CPU, 117... Supporting unit, 118... Conveying belt, 119... Support plate, 120... Belt roller, 121a-121h... Guide plate pair, 122a-122h... Conveying roller, 130... Head unit, 132... Ink tank, 133... Connection channel, 133a... Supply channel, 133b... Recovery flow Path, 134... Circulation pump, A1... Conveyance path, C1... Pressure chamber, C2... Air chamber, C3... Common chamber.

Claims (5)

A nozzle plate having a plurality of nozzles,
A plurality of wall portions having a joining surface joined to the nozzle plate; a plurality of first grooves arranged on one side of the wall portion and forming pressure chambers communicating with the plurality of nozzles; An actuator base having a plurality of second grooves arranged on the other side,
The nozzle plate and the actuator base are joined via an adhesive between the joining surface of the plurality of wall portions and the nozzle plate, and in the majority of the wall portions of the plurality of wall portions, An ink jet head in which an adhesive is arranged more biased toward the second groove side than the first groove side. An inkjet head according to claim 1;
An inkjet device, comprising: a transport device that transports a recording medium along a predetermined transport path. A nozzle plate having a nozzle, a wall portion having a joint surface joined to the nozzle plate, a first groove arranged on one side of the wall portion and communicating with the nozzle, and arranged on the other side of the wall portion. An ink-jet which is joined to an actuator base having a plurality of second grooves, respectively, via an adhesive which is biased more toward the second groove side than to the first groove side on the joint surface of the wall portion. Head manufacturing method. The method of manufacturing an inkjet head according to claim 3, wherein when the adhesive is applied to the wall portion or the nozzle plate, the application area or the application amount is biased toward the second groove side. In the state where the nozzle plate and the actuator base are attached with the adhesive disposed between the wall portion and the nozzle plate, the pressure of the first groove is set to the pressure of the second groove. The method for manufacturing an inkjet head according to claim 3, wherein the adhesive is biased toward the second groove side by increasing the height to a value higher than that of the second groove.