Liquid discharge head, liquid discharge apparatus, method of manufacturing article, and method of manufacturing liquid discharge head

Abstract

To provide a technique advantageous for reducing force acting on a plate of a liquid discharge head.SOLUTION: A liquid discharge head includes a plate having a nozzle surface including a nozzle hole for discharging liquid, and a frame-shaped first member fixed to a portion of the nozzle surface by an adhesive member and formed so as not to overlap the nozzle hole in a direction perpendicular to the nozzle surface. The first member has a linear expansion coefficient larger than that of the plate. Between a first position and a second position on a first side of the nozzle surface, the first position is closer to a first end of the first side than the second position. In a direction parallel to the nozzle surface and perpendicular to the first side, a first shortest distance from the first position to an inner peripheral edge of the first member is smaller than a second shortest distance from the second position to the inner peripheral edge of the first member.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a liquid ejection head, a liquid ejection device, a method for manufacturing an article, and a method for manufacturing a liquid ejection head. [Background technology]

[0002] Liquid ejection devices are used to form images by ejecting liquids such as ink onto media such as paper, and in industrial fields to form functional films by ejecting liquids such as ink onto media such as glass substrates and semiconductor substrates.

[0003] A liquid ejection device includes a liquid ejection head. The liquid ejection head has a chip plate with a nozzle surface including nozzle holes for ejecting liquid. When a medium is transported to a position facing the liquid ejection head, liquid is ejected from the nozzle holes, forming a pattern, such as an image or a functional film, on the medium. As patterns become more precise, the accuracy of the liquid that lands on the medium increases, resulting in a narrower distance between the liquid ejection head and the medium. Meanwhile, as media sizes continue to increase, the need to form patterns over large areas in a short period of time has increased, dramatically increasing the medium transport speed. Contact between the nozzle surface of the liquid ejection head and the medium due to particles or uneven thickness of the medium can damage the nozzle surface of the liquid ejection head, potentially resulting in liquid ejection failure or deviation in the liquid ejection direction. Patent Document 1 discloses that a protective member is provided on the liquid ejection head to protect the nozzle surface. The protective member is bonded to a portion of the nozzle surface with an adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-65011 Summary of the Invention [Problem to be solved by the invention]

[0005] The chip plate and the protective member are often made of different materials and have different linear expansion coefficients. When the chip plate and the protective member, which have different linear expansion coefficients, are bonded with an adhesive, forces such as compressive force, tensile force, or shear force may act on the chip plate and the protective member during the manufacturing process of the liquid ejection head. If excessive force acts on the chip plate, there is a problem that the chip plate may crack.

[0006] The present disclosure provides an advantageous technique for reducing the force acting on the plate of a liquid ejection head. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a liquid ejection head comprising: a plate having a nozzle surface including nozzle holes for ejecting liquid; and a frame-shaped first member fixed to a portion of the nozzle surface with an adhesive member and formed so as not to overlap the nozzle holes in a direction perpendicular to the nozzle surface, wherein the first member has a linear expansion coefficient greater than that of the plate; of a first position and a second position on a first side of the nozzle surface, the first position is closer to a first end of the first side than the second position; and in a direction parallel to the nozzle surface and perpendicular to the first side, a first shortest distance from the first position to an inner peripheral edge of the first member is shorter than a second shortest distance from the second position to the inner peripheral edge of the first member.

[0008] a step of applying adhesive to at least one of the plate and the first member; a step of aligning the plate and the first member by sandwiching the adhesive between them so that the nozzle holes do not overlap the first member in a direction perpendicular to the nozzle surface; and a step of hardening the adhesive to fix the plate and the first member, wherein the first member has a linear expansion coefficient greater than that of the plate; and wherein, of a first position and a second position on a first side of the nozzle surface, the first position is closer to a first end of the first side than the second position; and, after the adhesive is hardened, a first shortest distance from the first position to an inner peripheral edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than a second shortest distance from the second position to the inner peripheral edge of the first member. [Effects of the Invention]

[0009] According to the present disclosure, an advantageous technique for reducing the force acting on the plate of a liquid ejection head is provided. [Brief explanation of the drawings]

[0010] [Figure 1] 1A is a schematic top view of the liquid ejection device according to the first embodiment, and FIG. 1B is a schematic side view of the liquid ejection device according to the first embodiment. [Figure 2] 1A is a schematic perspective view of a liquid ejection head according to a first embodiment, FIG. 1B is a schematic plan view of the liquid ejection head according to the first embodiment, and FIG. 1C is a cross-sectional view of the liquid ejection head according to the first embodiment taken along line IIC-IIC′. [Figure 3] 1A is a schematic plan view of a liquid ejection head according to a comparative example, FIG. 1B is a schematic plan view of a protective member according to a comparative example, and FIG. 1C is a schematic plan view of a part of the protective member according to a comparative example. [Figure 4]1A is a schematic plan view of a bonding region between a chip plate and a protective member according to the first embodiment, and FIG. 1B is a schematic plan view of a part of the bonding region according to the first embodiment. [Figure 5] 10 is a table showing calculation results of forces generated between two members due to heat according to the first embodiment. [Figure 6] 10A is a schematic plan view of a liquid ejection head according to a second embodiment, and FIG. 10B is a schematic plan view of a bonding region of a chip plate and a protective member according to the second embodiment. [Figure 7] 1A is a schematic plan view of a liquid ejection head according to a third embodiment, FIG. 1B is a schematic plan view of a liquid ejection head according to a fourth embodiment, and FIG. 1C is a schematic plan view of a liquid ejection head according to a fifth embodiment. [Figure 8] 1A is a schematic plan view of a liquid ejection head according to Modification 1. FIG. 1B is a schematic plan view of a liquid ejection head according to Modification 2. FIG. 1C is a schematic plan view of a liquid ejection head according to Modification 3. [Figure 9] 10 is a table showing experimental results according to an example. DETAILED DESCRIPTION OF THE INVENTION

[0011] A liquid ejection head according to an embodiment of the present invention, a method for manufacturing a liquid ejection head, etc. will be described with reference to the drawings. Note that the following embodiment is merely an example, and those skilled in the art can appropriately modify and implement the detailed configuration, for example, without departing from the spirit of the present invention.

[0012] In the drawings referred to in the following description of the embodiments and examples, elements denoted by the same reference numerals have the same functions unless otherwise specified. When a plurality of identical elements are arranged in a drawing, the reference numerals and their descriptions may be omitted.

[0013] Furthermore, the drawings may be represented schematically for the convenience of illustration and explanation, and the shape, size, arrangement, etc. of elements depicted in the drawings may not necessarily strictly correspond to the actual objects.

[0014] In the following description, directions are indicated using an XYZ coordinate system, which is a Cartesian coordinate system. The X, Y, and Z axes are perpendicular to one another. The direction of the X axis is also referred to as the X direction, the direction of the Y axis as the Y direction, and the direction of the Z axis as the Z direction. For example, the positive direction of the X axis refers to the same direction as the X-axis arrow in the coordinate system shown in the figure, and the negative direction of the X axis refers to the direction 180 degrees opposite to the direction of the X-axis arrow in the coordinate system shown in the figure. Furthermore, when simply referred to as the X direction, it refers to a direction parallel to the X axis, regardless of whether it is in the direction indicated by the X-axis arrow in the figure. The same applies to the Y and Z axes other than the X axis. For example, a plane including the X and Y axes is referred to as an XY plane.

[0015] In addition, in this specification, the term "main component" refers to the component that is the largest in weight when the object is made up of multiple components (materials), meaning that the component in question accounts for 50% or more by weight.

[0016] In this specification, the liquid handled by the liquid ejection head may be referred to as "ink," but the ink according to the embodiment is not limited to a liquid containing a recording material for forming characters or images. For example, the ink may be a liquid containing a functional material for forming a functional thin film such as an electrode or an optical filter, or a functional element such as an organic EL element. It may also be a liquid containing an insoluble solid component.

[0017] Furthermore, the act of discharging a liquid onto an object is sometimes referred to as "recording," but the recording referred to here is not necessarily limited to recording information such as characters or images. For example, it also includes applying a liquid to an object to manufacture an article such as a functional thin film, a functional element, or a three-dimensional object. Furthermore, the object onto which the liquid is applied is sometimes referred to as a "recording medium," but this is not limited to a medium for recording information such as characters or images, and includes components (e.g., substrates) that serve as base materials for manufacturing articles such as a functional thin film, a functional element, or a three-dimensional object.

[0018] [First embodiment] A liquid ejection device according to a first embodiment will be described. Fig. 1(a) is a schematic top view of the liquid ejection device 1 according to the first embodiment. Fig. 1(b) is a schematic side view of the liquid ejection device 1 according to the first embodiment. For ease of illustration, elements constituting the liquid ejection device 1, such as a power supply and a device cover, are omitted from Figs. 1(a) and 1(b).

[0019] The liquid ejection device 1 includes a base 9. The base 9 is provided with a stage 10 on which a recording medium 6 is set. The recording medium 6 is, for example, a substrate for forming an organic EL element. A sub-scanning guide rail 7 extending in the X direction in a plan view is fixed to the base 9 via a support member 8. A main scanning guide rail 5 serving as a carriage movable on the sub-scanning guide rail 7 in the X direction is mounted on the sub-scanning guide rail 7. A main scanner 4 movable on the main scanning guide rail 5 in the Y direction is mounted on the main scanning guide rail 5. A liquid ejection unit 2 capable of ejecting liquid toward the recording medium 6 is attached to the main scanner 4. By moving the main scanning guide rail 5 in the X direction and the main scanner 4 in the Y direction, the liquid ejection unit 2 can be freely scanned in the X and Y directions over the recording medium 6 set on the stage 10. In this way, the liquid ejection device 1 can move the liquid ejection unit 2 to perform scanning. However, the scanning mechanism is not limited to the configuration shown in the figure and may have any configuration as long as it can scan the liquid ejection unit 2 relative to the recording medium 6. For example, the recording medium 6 may be moved in one of the X and Y directions, and the liquid ejection unit 2 may be moved in the other direction. Alternatively, the liquid ejection unit 2 may be fixed, and the recording medium 6 may be moved in both the X and Y directions.

[0020] The liquid ejection unit 2 is equipped with a liquid ejection head 100 capable of ejecting liquid toward the recording medium 6. The liquid is, for example, ink for forming organic EL elements. The liquid ejection head 100 is equipped with liquid ejection elements that apply pressure to ink by utilizing, for example, deformation of a piezoelectric element or boiling caused by a heating element, thereby ejecting the ink from the nozzles.

[0021] A main tank 11 is installed on the base 9. The main tank 11 is an example of a tank for supplying liquid to the liquid ejection head 100. The main tank 11 stores ink to replenish the ink when the remaining ink level in the sub-tank of the liquid ejection unit 2 decreases. The main tank 11 is connected to a flow path 15 for circulating the stored ink.

[0022] The liquid ejection device 1 is provided with a flow path 14 that opens and closes between a sub-tank of the liquid ejection unit 2 and a first flow path 15. Since the sub-tank moves as the liquid ejection unit 2 is scanned in the XY directions, the flow path 14 is configured to include a flexible piping portion.

[0023] The liquid ejection device 1 includes a liquid ejection head 100 in which the ejection openings of multiple nozzles are aligned and mechanical strength is ensured. This allows, for example, stable production of organic EL elements over a long period of time. Alternatively, high-quality recording using information recording ink can be performed stably over a long period of time.

[0024] 2(a) is a schematic perspective view of the liquid ejection head 100 according to the first embodiment. The liquid ejection head 100 is attached to a liquid ejection unit 2 shown in FIG. 1, which is made up of a holder, piping, and the like.

[0025] The liquid ejection head 100 includes a protective member 101, a tip plate 102, an adhesive member 103, a frame member 104, a flexible flat cable 105, and a base 106. The tip plate 102 is an example of a plate. The protective member 101 is an example of a first member. The frame member 104 is an example of a second member. The base 106 is an example of a third member.

[0026] Fig. 2(b) is a schematic plan view of the liquid ejection head 100 according to the first embodiment. Fig. 2(c) is a cross-sectional view taken along the line IIC-IIC' of the liquid ejection head 100 according to the first embodiment. That is, Fig. 2(c) schematically illustrates the cross section of the liquid ejection head 100 taken along the IIC-IIC' plane parallel to the XZ plane shown in Fig. 2(b), viewed in the negative direction of the Y axis. Fig. 2(b) also schematically illustrates the liquid ejection head 100 viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 hidden by the protective member 101 are illustrated by dashed lines for convenience.

[0027] The tip plate 102 is a plate-shaped member. That is, the tip plate 102 has a rectangular parallelepiped shape. When viewed in the Z direction, the tip plate 102 has a rectangular shape. The tip plate 102 has a plurality of nozzle holes 120, a plurality of liquid chambers (not shown), and a plurality of liquid flow paths (not shown) defined therein.

[0028] The chip plate 102 has a nozzle surface 121 including a plurality of nozzle holes 120, a back surface 122 opposite the nozzle surface 121, and four side surfaces. The Z direction is a direction perpendicular to the nozzle surface 121. The Y direction is the longitudinal direction of the nozzle surface 121. The X direction is the lateral direction of the nozzle surface 121. The nozzle surface 121 faces in the negative direction of the Z axis. The back surface 122 faces in the positive direction of the Z axis. The nozzle surface 121 is a surface parallel to the XY plane. Liquid is ejected from each of the plurality of nozzle holes 120 in the negative direction of the Z axis.

[0029] The nozzle surface 121 is a rectangular surface and has four sides S1, S2, S3, and S4. Sides S1 and S3 are parallel to each other, and sides S2 and S4 are parallel to each other. Sides S1 and S3 intersect (are perpendicular to) each other with sides S2 and S4. The two sides S1 and S3 that face each other in the X direction are long sides that extend in the Y direction. The two sides S2 and S4 that face each other in the Y direction are short sides that extend in the X direction. In other words, sides S1 and S3 are longer than sides S2 and S4.

[0030] A plurality of liquid ejection elements (not shown) are arranged inside the chip plate 102. Each of the plurality of liquid ejection elements (not shown) imparts energy to the liquid to eject the liquid from a corresponding one of the plurality of nozzle holes 120.

[0031] The back surface 122 of the chip plate 102 is fixed to the base 106 with an adhesive member (not shown). The base 106 has a supply port for supplying ink to the chip plate 102. The adhesive member is a cured adhesive.

[0032] The frame member 104 is a frame-shaped member with an open center that surrounds the outer periphery of the tip plate 102. The frame member 104 is supported by a base 106. The frame member 104 is fixed to the base 106 with screws 107. The frame member 104 has a surface 141 that faces in the same direction as the nozzle surface 121. Note that a spacer 108 may be disposed between the frame member 104 and the base 106 to align the heights in the Z direction between the nozzle surface 121 of the tip plate 102 and the surface 141 of the frame member 104. That is, the frame member 104 may be supported by the base 106 via the spacer 108.

[0033] A flexible flat cable 105 is electrically and mechanically connected to the chip plate 102. Specifically, electrical contacts are provided on one side surface 123 of the two side surfaces of the chip plate 102 in the X direction, and the flexible flat cable 105 is electrically and mechanically connected to the electrical contacts. The electrical contacts are electrically connected to the liquid ejection elements in the chip plate 102. The flexible flat cable 105 is used as a transmission path for signals that drive the liquid ejection elements in the chip plate 102. A gap 109 is provided between the chip plate 102, the frame member 104, and the base 106. The flexible flat cable 105 is arranged along the gap 109 and is pulled out from between the frame member 104 and the base 106 on the side surface of the liquid ejection head 100 to the outside and connected to a control board (not shown).

[0034] 2(c) shows only one flexible flat cable 105, but the present invention is not limited to this. The liquid ejection head 100 may include two or more flexible flat cables. For example, the liquid ejection head 100 may include two flexible flat cables. One of the two flexible flat cables may be connected to one of the two side surfaces of the chip plate 102 in the X direction, and the other of the two flexible flat cables may be connected to the other of the two side surfaces of the chip plate 102 in the X direction.

[0035] The protective member 101 is a plate-shaped member. The protective member 101 is fixed to a portion of the nozzle surface 121 of the chip plate 102 with an adhesive member 103. The protective member 101 is a frame-shaped member formed so as not to overlap the plurality of nozzle holes 120 in the Z direction. In other words, the protective member 101 is formed in a shape with an opening in the center so as to surround the plurality of nozzle holes 120. The protective member 101 is disposed across the chip plate 102 and the frame member 104, and is fixed to the chip plate 102 and the frame member 104 via the adhesive member 103. The adhesive member 103 is a cured adhesive.

[0036] By providing the protective member 101 on the nozzle surface 121 side of the chip plate 102, it is possible to reduce damage to the nozzle surface 121 caused by particles or uneven thickness of the recording medium 6, and to reduce non-ejection of liquid, deviation of the liquid ejection direction, etc. This makes it possible to prevent poor liquid ejection from occurring in the liquid ejection head 100.

[0037] Furthermore, the protective member 101 is disposed so as to overlap the chip plate 102 and the frame member 104 in the Z direction, and is fixed to the chip plate 102 and the frame member 104. In the first embodiment, the protective member 101 is disposed so as to overlap a portion of the nozzle surface 121 of the chip plate 102 and a portion of the surface 141 of the frame member 104 in the Z direction, and is fixed to a portion of the nozzle surface 121 of the chip plate 102 and a portion of the surface 141 of the frame member 104 with an adhesive member 103.

[0038] 2(c), both the nozzle surface 121 and the surface 141 are fixed to the protective member 101 with the adhesive member 103, but this is not limiting. For example, the protective member 101 and the nozzle surface 121 of the chip plate 102 may be fixed with the adhesive member 103, and the protective member 101 and the surface 141 of the frame member 104 may be fixed with an adhesive member (not shown) that is different from the adhesive member 103.

[0039] Furthermore, ink ejected from the nozzle holes 120 of the liquid ejection head 100 may become mist and re-adhere to the nozzle surface 121 of the chip plate 102. Electrical contacts to which the flexible flat cable 105 is connected are disposed on the side surface 123 of the chip plate 102. The protective member 101 is disposed so as to cover the gap 109 shown in white in FIG. 2(b). The gap 109 is sealed with the protective member 101 and the adhesive member 103, thereby preventing ink from entering the gap 109 and from flowing around the side surface 123 of the chip plate 102. In this way, the protective member 101 can prevent ink from entering the gap 109, thereby preventing short circuits from occurring in the electrical contacts of the chip plate 102. This prevents liquid ejection problems from occurring in the liquid ejection head 100.

[0040] The chip plate 102 has minute ink flow paths and minute nozzle holes 120 formed therein. Due to the miniaturization of the internal structure of the chip plate 102, it is preferable that the chip plate 102 be manufactured using a semiconductor process, and silicon is preferably used as the main material, i.e., the main component, of the chip plate 102. The chip plate 102 has a layered structure in which multiple silicon wafers are stacked. The thickness of the thinnest layer in the layered structure is approximately several tens to several hundred μm.

[0041] Furthermore, the frame member 104 is provided on the base 106 mainly to cover the base 106 and the flexible flat cable 105. From the viewpoint of workability and the like, a metal is preferably used as the main component of the frame member 104. The metal is a pure metal or an alloy. Examples of metals used as the main component of the frame member 104 include aluminum, invar, kovar, titanium, and stainless steel.

[0042] As shown in Figures 2(a), 2(b), and 2(c), when one chip plate 102 is provided for one frame member 104, aluminum or stainless steel is preferably used as the main component of the frame member 104, among metals.

[0043] In addition, if the area of ​​the coating region where the liquid is to be coated increases as the recording medium 6 increases in size, the liquid ejection head 100 may include multiple tip plates 102 arranged in a staggered pattern. In such cases, multiple tip plates 102 may be provided for one frame member 104, resulting in a large frame member 104. As the frame member 104 increases in size, the tip plates 102 become more susceptible to the effects of the linear expansion of the frame member 104 via the protective member 101 and adhesive member 103. Therefore, it is preferable that the main component of the frame member 104 be a metal with a low linear expansion coefficient. For example, among metals, invar, kovar, titanium, or stainless steel is preferably used as the main component of the frame member 104. As the stainless steel, martensitic stainless steel is preferably used.

[0044] The protective member 101 is disposed on the nozzle surface 121 of the tip plate 102. Therefore, of the protective member 101 and the tip plate 102, the protective member 101 is disposed closer to the recording medium 6 than the tip plate 102. The protective member 101 is located at a position closest to the recording medium 6 within the liquid ejection head 100. As a result, the nozzle surface 121 is protected by the protective member 101.

[0045] The protective member 101 is a component that may come into contact with the recording medium 6, and therefore is required to be strong. The liquid ejection head 100 also requires recovery operations, such as wiping off ink adhering to the nozzle surface 121 of the tip plate 102 with a wiper and suctioning ink remaining in the nozzle holes 120 after a pause using a suction mechanism. Even during such recovery operations, the protective member 101 may come into contact with the wiper or suction mechanism, and therefore is required to be durable. From the viewpoint of achieving both strength and durability, a metal is preferably used as the main component of the protective member 101. The metal may be a pure metal or an alloy. Examples of metals used as the main component of the protective member 101 include alloys such as invar, kovar, and stainless steel, as well as titanium. Thus, the material of the protective member 101 is different from the material of the tip plate 102.

[0046] Since the protective member 101 is fixed to the chip plate 102 by the adhesive member 103 , it is preferable that the linear expansion coefficient of the protective member 101 is close to that of the chip plate 102 .

[0047] Here, we will explain the manufacturing method of the liquid ejection head 100. First, in the first step, the protective member 101, the chip plate 102, the frame member 104, and the base 106 are prepared. At this time, an assembly is prepared in which the chip plate 102 is fixed to the base 106 and the frame member 104 is fixed to the base 106 with screws 107.

[0048] Next, in the second step, an adhesive, which is a raw material of the adhesive member 103, is applied to the protective member 101. The term "adhesive" refers to a substance used for adhesion that is uncured and has viscosity or fluidity. In the first embodiment, the adhesive applied to the protective member 101 is preferably a thermosetting or photosetting adhesive, which will be described later. This type of adhesive has fluidity or viscosity at room temperature, but hardens when heated or exposed to light. Note that photosetting adhesives may be exposed to high temperatures when hardened by exposure to light. Of these adhesives, thermosetting adhesives are preferably used.

[0049] Next, in a third step, the adhesive is sandwiched between the chip plate 102 and the protective member 101 so that the nozzle holes 120 do not overlap the protective member 101 in the Z direction, the chip plate 102 and the protective member 101 are aligned with the adhesive sandwiched between the frame member 104 and the protective member 101, and the frame member 104 and the protective member 101 are aligned. At this time, it is preferable that the protective member 101 and the chip plate 102 are pressurized, and the protective member 101 and the frame member 104 are pressurized so that the thickness of the adhesive is uniform. Note that the adhesive only needs to be interposed between the protective member 101 and the chip plate 102 and between the protective member 101 and the frame member 104, and the adhesive may be applied to the chip plate 102 and the frame member 104, or may be applied to the protective member 101, the chip plate 102, and the frame member 104. That is, in the case of the chip plate 102 and the protective member 101, it is sufficient that the adhesive is supplied to at least one of the chip plate 102 and the protective member 101. In the case of the frame member 104 and the protective member 101, it is sufficient that the adhesive is supplied to at least one of the frame member 104 and the protective member 101.

[0050] Next, in the fourth step, a heat treatment is performed to harden the adhesive, thereby fixing the chip plate 102 and the protective member 101 with the adhesive member 103, and fixing the frame member 104 and the protective member 101 with the adhesive member 103. The adhesive is hardened, and the liquid ejection head 100 including the adhesive member 103 is cooled.

[0051] When printing on paper or film, the distance between the tip plate 102 and the recording medium 6 is on the order of millimeters. On the other hand, when printing on a flat panel of a display, the distance between the tip plate 102 and the recording medium 6 is on the order of submillimeters. Therefore, the protective member 101 placed on the nozzle surface 121 of the tip plate 102 preferably has a thickness on the order of several tens of micrometers and a shape that is free of protruding burrs or other defects. Furthermore, the protective member 101 is preferably fixed to the nozzle surface 121 of the tip plate 102 with submillimeter precision, and the opening shape of the protective member 101 is preferably formed with precision one order of magnitude smaller than that precision. To satisfy this requirement for the protective member 101, the protective member 101 is preferably fabricated by laser processing or etching using photolithography, rather than by mechanical processing such as punching.

[0052] The protective member 101 may be required to have strength, durability, and processability, and in some cases, the surface of the protective member 101 may be required to be coated with a liquid-repellent film. Considering the film-forming properties of the liquid-repellent film, titanium or an alloy containing iron, cobalt, nickel, and chromium, among other metals, is preferably used as the main component of the protective member 101. Furthermore, for example, invar or kovar is preferably used as the alloy.

[0053] The adhesive member 103 must have sufficient adhesion to the protective member 101, the chip plate 102, and the frame member 104. Furthermore, since the adhesive member 103 serves as a sealing portion that seals the gap 109, it is preferable that the adhesive member 103 has high durability against ink. From this perspective, a bisphenol-based epoxy resin or the like is preferably used for the adhesive member 103. The adhesive member 103 must have an adhesion force stronger than the force generated due to the difference in linear expansion coefficient between the two members, i.e., between the protective member 101 and the chip plate 102, and between the protective member 101 and the frame member 104. The generated force is a compressive force, a tensile force, or a shear force.

[0054] The adhesive member 103 is a cured adhesive. Room-temperature curing, thermosetting, or photocuring resins (adhesives) can be used as the adhesive. However, to bond two components with high precision, it is preferable that the adhesive be cured in a short time after the two components are aligned, and a photocuring resin or a thermosetting resin is preferably used as the adhesive. Photocuring resins are the adhesives that cure in the shortest time, but it is difficult to irradiate all of the adhesive applied between the chip plate 102 and the protective member 101 with light. Furthermore, when a photocuring resin is used as the adhesive, the initiator is likely to remain in the adhesive member 103. For this reason, a thermosetting resin is preferably used as the adhesive.

[0055] When the adhesive is a thermosetting resin, the manufacturing process of the liquid ejection head 100 includes a heating step of heating the adhesive to harden it. Even if the adhesive is a photocurable resin, the adhesive may be heated to harden it. When hardening the adhesive, the protective member 101, the chip plate 102, and the frame member 104 thermally expand due to heating. After the adhesive hardens, the protective member 101, the chip plate 102, and the frame member 104 thermally contract during the cooling process. The protective member 101 has a larger linear expansion coefficient than the chip plate 102. This means that there is a difference between the linear expansion coefficients of the protective member 101 and the chip plate 102, and forces such as compressive, tensile, or shearing forces act on the chip plate 102.

[0056] Although it depends on the thickness of the adhesive, the adhesive expands or compresses as it hardens, generating a force associated with this deformation. To reduce the effects of expansion or compression as the adhesive hardens and to make the thickness of the adhesive member 103 after hardening uniform, the adhesive member 103 (adhesive) may contain filler particles as an additive. Suitable filler particles include inorganic oxides such as silica, alumina, or titania. The filler particles are not limited to the above examples, as long as they can be adjusted to a thickness that will not damage the adhesive member 103 even when pressure is applied to the adhesive member 103 after hardening.

[0057] Here, a liquid ejection head of a comparative example will be described. Fig. 3(a) is a schematic plan view of a liquid ejection head 100X according to the comparative example. The liquid ejection head 100X includes a protective member 101X, a chip plate 102X, and a frame member 104X. The chip plate 102X has a similar configuration to the chip plate 102, and the frame member 104X has a similar configuration to the frame member 104, but the protective member 101X has a different configuration from the protective member 101. The protective member 101X is disposed across the chip plate 102X and the frame member 104X and is fixed to the chip plate 102X and the frame member 104X with an adhesive member.

[0058] 3(a) schematically illustrates the liquid ejection head 100X as viewed in the negative direction of the Z axis, and for convenience, the portion of the liquid ejection head 100X that is hidden by the protective member 101X is illustrated by a dashed line. The protective member 101X is disposed so as to cover the gap 109X, which is illustrated in white in FIG. 3(a). The gap 109X is the gap between the chip plate 102X and the frame member 104X.

[0059] The protective member 101X has a rectangular opening in the center so as not to overlap the nozzle holes 120X of the tip plate 102X in the Z direction. Fig. 3(b) is a schematic plan view of the protective member 101X according to the comparative example. The inner peripheral edge 111X of the protective member 101X is rectangular.

[0060] 3(c) is a schematic plan view of a portion of the region of the protective member 101X according to the comparative example that overlaps with the chip plate 102X in the Z direction. That is, FIG. 3(c) illustrates only a portion of the bonding region R0X of the protective member 101X that is bonded to the chip plate 102X. Region RB in FIG. 3(c) is an end region of the bonding region R0X, where the force generated between the protective member 101X and the chip plate 102X is the highest. 3(c), the force generated between the protection member 101X and the chip plate 102X is indicated by different shades of black. The darker the black, the stronger the force generated.

[0061] The amount of displacement of the center of the protective member 101X due to thermal expansion of the protective member 101X is small. However, the amount of displacement of the edges of the protective member 101X due to thermal expansion of the protective member 101X is large because it is the sum of the displacements from the center to the edges. In this way, the components 101X, 102X, and 104X are bonded with adhesive in a thermally expanded state, and the protective members 101X, 102X, and 104X thermally contract during the cooling process. Therefore, when the inner peripheral edge 111X is rectangular, the areas near the edges of each side of the chip plate 102X are most affected by linear expansion, resulting in greater compressive, tensile, or shear forces than other areas. The four corners of the chip plate 102X are the edges in both the longitudinal and lateral directions, and are therefore the areas subjected to the greatest forces. This raises the risk of the chip plate 102X cracking from the four corners.

[0062] Industrial liquid ejection devices are becoming increasingly precise in their image resolution, and as a result, liquid ejection heads are being required to eject minute amounts of liquid, achieve high-precision liquid impact accuracy, and deliver stable liquid ejection. In particular, the inks used in industrial liquid ejection devices are special solvent inks, which often suffer from drying and moisture absorption. Therefore, structural improvements have been implemented, such as incorporating an ink circulation mechanism inside the liquid ejection head and shortening the nozzle length. The chip plate 102X has a layered structure consisting of multiple silicon wafers, with the thinnest layer in the layered structure having a thickness of approximately several tens to several hundred microns. Therefore, thermal deformation, such as thermal expansion or contraction, of the protective members 101X, 102X, and 104X can significantly increase the risk of cracking or chipping due to compressive, tensile, or shear forces.

[0063] FIG. 4(a) is a schematic plan view of the bonding region R0 of the tip plate 102 and the protective member 101 according to the first embodiment. FIG. 4(b) is a schematic plan view of a portion of the bonding region R0 according to the first embodiment. The bonding region R0 of the protective member 101 is a portion of the protective member 101 that overlaps with a portion of the tip plate 102 in the Z direction. That is, FIG. 4(a) illustrates the bonding region R0 of the protective member 101 that is bonded to a portion of the tip plate 102. As shown in FIG. 4(a), an opening is defined by an inner peripheral edge 111 of the protective member 101 that surrounds multiple nozzle holes 120. The longitudinal ends of the opening in the protective member 101 are wider in the lateral direction than the longitudinal center of the opening. The longitudinal direction is the Y direction, and the lateral direction is the X direction.

[0064] The nozzle surface 121 has four sides S1 to S4. Side S1 is an example of a first side. Side S1 is a side that extends in the Y direction and includes two ends E1 and E2 in the Y direction and a center C1 in the Y direction. The center C1 is the center in the Y direction between end E1 and end E2.

[0065] The following description focuses on two positions P1 and P2 on side S1. Position P1 is an example of a first position, and position P2 is an example of a second position. End E1 is an example of a first end. End E2 is an example of a second end. End E2 is the end of side S1 opposite end E1. Of the two positions P1 and P2, position P1 is closer to end E1 of side S1 than position P2. In the first embodiment, position P2 is located at the center C1 of side S1. Furthermore, each of ends E1 and E2 is one of the four corners of the nozzle surface 121.

[0066] In the X direction, which is parallel to the nozzle surface 121 and perpendicular to the side S1, the shortest distance from position P1 to the inner circumferential edge 111 of the protective member 101 is defined as L1. The shortest distance L1 is the straight-line distance in the X direction. In addition, the shortest distance in the X direction from position P2 to the inner circumferential edge 111 of the protective member 101 is defined as L2. The shortest distance L2 is the straight-line distance in the X direction. The shortest distance L1 is an example of a first shortest distance. The shortest distance L2 is an example of a second shortest distance. The shortest distance L1 is shorter than the shortest distance L2.

[0067] Here, when viewed in the Z direction, an imaginary line extending in the X direction and including position P1 touches the inner circumferential edge 111 of the protective member 101 at one or more points. When, when viewed in the Z direction, an imaginary line extending in the X direction and including position P1 touches only one point on the inner circumferential edge 111 of the protective member 101, the shortest distance L1 is the distance from position P1 to the one point. When, when viewed in the Z direction, an imaginary line extending in the X direction and including position P1 touches multiple points on the inner circumferential edge 111 of the protective member 101, the shortest distance L1 is the distance from position P1 to the point that is closest to position P1 among the multiple points.

[0068] Similarly, when viewed in the Z direction, an imaginary line extending in the X direction and including position P2 touches the inner circumferential edge 111 of the protective member 101 at one or more points. When, when viewed in the Z direction, an imaginary line extending in the X direction and including position P2 touches only one point on the inner circumferential edge 111 of the protective member 101, the shortest distance L2 is the distance from position P2 to the one point. When, when viewed in the Z direction, an imaginary line extending in the X direction and including position P2 touches multiple points on the inner circumferential edge 111 of the protective member 101, the shortest distance L2 is the distance from position P2 to the point closest to position P2 among the multiple points. In the first embodiment, when viewed in the Z direction, an imaginary line extending in the X direction and including position P2 touches the inner circumferential edge 111 at two points.

[0069] Furthermore, when viewed in the Z direction, multiple imaginary straight lines extending in the X direction that intersect with side S1 and the inner circumferential edge 111 can be defined. That is, side S1 includes multiple positions that intersect with these multiple imaginary straight lines. Position P1 is the position with the shortest distance to the inner circumferential edge 111 among multiple positions on side S1 toward end E1 with respect to center C1. Position P2 is the position with the longest distance to the inner circumferential edge 111 among multiple positions on side S1.

[0070] The shortest distance L1 is the width of the bonding region R0 at position P1. The shortest distance L2 is the width of the bonding region R0 at position P2. Because the width L1 of the bonding region R0 at the longitudinal end near position P1 is narrower than the width L2 of the longitudinal center near position P2, forces such as compression, tension, or shear force generated by the difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the chip plate are reduced. This reduces the force applied to the end of the chip plate 102, thereby preventing the chip plate 102 from cracking.

[0071] In the bonding region R0, it is preferable that the end portions included in the longitudinal end regions RD are narrower than the central portion included in the longitudinal central region RC. In other words, it is preferable that the area of ​​the longitudinal end regions RD in the bonding region R0 is smaller than the area of ​​the longitudinal central region RC. The end region RD is the end region on the side of end E1 of ends E1 and E2.

[0072] The edge region RD will now be described. For example, a square region A1 included in the nozzle surface 121 is defined. Region A1 is a region that includes the end E1 of side S1 of the nozzle surface 121. In the Z direction, the edge region RD is a region of the protective member 101 that overlaps with region A1. In the edge region RD shown in FIG. 4(b), the force generated between the protective member 101 and the chip plate 102 is indicated by shades of black. The darker the black, the greater the force generated.

[0073] As described above, the bonding area at the longitudinal ends of the bonding region R0 is smaller than that at the longitudinal center of the bonding region R0, so that forces such as compression, tension, or shear force generated by the difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the chip plate are reduced. This reduces the force applied to the ends of the chip plate 102. In other words, this provides a technology that is advantageous for reducing the force acting on the chip plate 102 of the liquid ejection head 100. As a result, cracking of the chip plate 102 is suppressed.

[0074] Because the chip plate 102 is brittle and prone to cracking, the bonding between the protective member 101 and the chip plate 102 must prevent cracking of the chip plate 102 and peeling of the adhesive member 103, which are opposing phenomena. Therefore, the minimum distance L1 is preferably 10% to 80% of the minimum distance L2. That is, it is preferable that 0.1≦(L1 / L2)≦0.8. By setting L1 / L2 to 0.1 or greater, the adhesion between the adhesive member 103 and the protective member 101 and between the adhesive member 103 and the chip plate 102 at the end near position P1 is increased, reducing the likelihood of peeling between the adhesive member 103 and the protective member 101 and the adhesive member 103 and the chip plate 102. Furthermore, by setting L1 / L2 to 0.8 or less, the force generated by the difference between the linear expansion coefficients of the protective member 101 and the chip plate 102 can be sufficiently reduced. This sufficiently reduces the possibility of cracking the chip plate 102. The value of L1 / L2 may be appropriately designed depending on the combination of the material of the protective member 101 and the type of adhesive.

[0075] Next, we will focus on two positions P2 and P3 on side S1. Position P3 is an example of a third position. Of the two positions P2 and P3, position P3 is closer to end E2 of side S1 than position P2. Position P3 is the position with the shortest distance to the inner circumferential edge 111 among multiple positions on side S1 closer to end E2 than center C1.

[0076] In the X direction, which is parallel to the nozzle surface 121 and perpendicular to the side S1, the shortest distance from the position P3 to the inner peripheral edge 111 of the protective member 101 is defined as L3. The shortest distance L3 is a linear distance in the X direction. The shortest distance L3 is an example of a third shortest distance. The shortest distance L3 is shorter than the shortest distance L2. This prevents the chip plate 102 from cracking, even in the edge region on the side of the end E2 opposite the end E1.

[0077] The minimum distance L3 is preferably 10% to 80% of the minimum distance L2. That is, it is preferable that 0.1≦(L3 / L2)≦0.8. This effectively prevents cracking of the chip plate 102 and peeling of the adhesive member 103, even in the end region on the side of the end E2 opposite the end E1.

[0078] The configuration of the side S1 of the protective member 101 has been described above, but the present invention is not limited to this. The configuration of the side S3 of the protective member 101 may also be the same as the configuration of the side S1. This reduces the force applied to the four corners of the chip plate 102, effectively preventing the chip plate 102 from cracking. Furthermore, the protective member 101 does not necessarily have to be formed as a single piece. For example, it may have a cut.

[0079] Here, a specific example will be described. In FIG. 4(b), L1 = 1 mm, L2 = 2 mm, and L1 / L2 = 0.5. Furthermore, if the bonding width in the short direction in the edge region RD is 1.5 mm, the bonding area in the 5 mm square region A1 is reduced to approximately 80% of the bonding area in the 5 mm square region A1' shown in FIG. 3(c). As a result, the force generated in the edge region RD is reduced. Furthermore, as described above, since the linear expansion of the protective member 101 is less affected near the center of the bonding region R0, the central region RC may have the same width as the central region of the bonding region R0X shown in FIG. 3(c). In this central region RC, the adhesive force between the protective member 101 and the chip plate 102 can be maintained.

[0080] Also, for example, L1 = 0.5 mm, L2 = 2 mm, and L1 / L2 = 0.25. In this case, the bonding area in the 5 mm square region A1 is reduced to about 70% of the bonding area in the 5 mm square region A1' shown in FIG. 3(c). As a result, the force generated in the end region RD is reduced, and cracking of the chip plate 102 in the end region RD can be suppressed.

[0081] Since the protective member 101 is fixed to both the chip plate 102 and the frame member 104 with the adhesive member 103, it is effective to prevent cracking of the chip plate 102 and peeling of the adhesive member 103 if the linear expansion coefficient of the protective member 101 is close to the linear expansion coefficients of the chip plate 102 and the frame member 104.

[0082] Silicon may be selected as the main component of the chip plate 102. In this case, it is preferable that both the protective member 101 and the frame member 104 have a linear expansion coefficient similar to that of silicon, but it is not realistic to make all of the members 101, 102, and 104 have the same linear expansion coefficient. For example, although there are alloys with linear expansion coefficients close to that of silicon, these alloys may not necessarily be used as the material for the protective member 101 and the frame member 104.

[0083] To effectively prevent cracking of the chip plate 102 and peeling of the adhesive member 103, it is preferable that the relationship be "linear expansion coefficient of chip plate 102 < linear expansion coefficient of protective member 101 ≦ linear expansion coefficient of frame member 104".

[0084] FIG. 5 is a table showing calculation results of the force generated by heat between two members according to the first embodiment. In FIG. 5, the row items indicate the material of the protective member 101, and the column items indicate the material of the chip plate 102 and the material of the frame member 104. In FIG. 5, the force generated between the protective member 101 and the chip plate 102 and the force generated between the protective member 101 and the frame member 104 are shown in association with the materials of each of the members 101, 102, and 104. In FIG. 5, the unit of the force generated between the two members is megapascals (MPa). In addition, in FIG. 5, the linear expansion coefficient (ppm / °C) of each material is shown below the name of each material.

[0085] As described above, the chip plate 102 is preferably primarily made of silicon. That is, it is preferable that the material of the chip plate 102 is primarily made of silicon. Furthermore, because the chip plate 102 contains fine structures such as liquid chambers and liquid flow paths, the chip plate 102 is prone to cracking when subjected to excessive force. That is, when bonding the protective member 101 and the chip plate 102, it is necessary to prevent cracking of the chip plate 102 and peeling of the adhesive member 103. However, there is a risk that cracking of the chip plate 102 will occur before peeling of the adhesive member 103 occurs. Taking into consideration the adhesion to the chip plate 102, a material with a linear expansion coefficient smaller than that of the chip plate 102 is selected for the protective member 101. Furthermore, considering the difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the frame member 104, kovar or titanium is preferably used as the primary component of the protective member 101, among metals, and kovar is preferably used among kovar and titanium.

[0086] On the other hand, in the joint between the protective member 101 and the frame member 104, there is a low risk of cracking as in the chip plate 102, and there is a high risk of only peeling occurring in the adhesive member 103. From this perspective, stainless steel or aluminum is preferably used as the main component of the frame member 104, among metals. From the perspective of the workability and cost of the frame member 104, stainless steel is preferably used as the main component of the frame member 104, among metals.

[0087] The stainless steel is preferably stainless steel designated as SUS403 in JIS (Japanese Industrial Standards) or stainless steel designated as SUS309S in JIS. Hereinafter, stainless steel designated as SUS403 in JIS will be simply referred to as "SUS403." Furthermore, stainless steel designated as SUS309S in JIS will be simply referred to as "SUS309S."

[0088] SUS403 is a stainless steel containing less than 0.15% carbon (C), less than 0.50% silicon (Si), less than 1.00% manganese (Mn), less than 0.040% phosphorus (P), less than 0.030% sulfur (S), less than 2.00% nickel (Ni), and between 11.50% and 13.00% chromium (Cr).

[0089] SUS309S is a stainless steel containing less than 0.08% carbon (C), less than 1.00% silicon (Si), less than 2.00% manganese (Mn), less than 0.045% phosphorus (P), less than 0.030% sulfur (S), between 12.00% and 15.00% nickel (Ni), and between 22.00% and 24.00% chromium (Cr).

[0090] SUS403 is a martensitic stainless steel with a low coefficient of linear expansion and significant cost benefits. SUS309S is an austenitic stainless steel with better chemical resistance than martensitic stainless steels. These can be selected based on the ink being used.

[0091] Aluminum is lightweight and inexpensive, but it has a large linear expansion coefficient, and when joining aluminum to titanium, which has a large linear expansion coefficient out of the kovar and titanium preferred for the protective member 101, a force of 50 MPa is generated, so an adhesive with a strong adhesive strength must be selected depending on the generated force.

[0092] Although alumina is a material with a small linear expansion coefficient and generates a small force, it is not practical due to its low workability.

[0093] The force generated by heat between the two members shown in Figure 5 is calculated based on the following formula. The two members are subjected to forces due to the thermal distortion that each receives due to heat, and the distortion due to constraints that affect each other when the two members are connected by adhesive, and the force generated by heat between the two members is calculated using the following formula derived from Hooke's law under the condition that these forces are balanced. Thermal stress = ((E1×E2)×(α1-α2)×(T1−T0)) / (E1+E2) E1, E2: Young's modulus α1, α2: Linear expansion coefficient T1: adhesive curing temperature (100°C) T0: Normal temperature (25℃)

[0094] If the force acting between the two members is equal to or less than the adhesion strength of the adhesive member 103, the likelihood of peeling occurring in the adhesive member 103 decreases. The adhesion strength of the adhesive member 103 can be expressed in terms of shear strength and tensile strength, but since linear expansion due to heat causes peeling when joining the protective member 101 and the adhesive member 103, it is considered sufficient for the shear strength of the adhesive member 103 to be greater than the force acting between the two members. The shear strength of epoxy resin is several tens of megapascals, depending on the type of adhesive and the members to be bonded.

[0095] If the difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the frame member 104 is greater than 6 ppm / °C, the force acting between the two members will likely exceed the shear strength of the adhesive member 103, causing peeling. Therefore, it is preferable that the difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the frame member 104 be 6 ppm / °C or less.

[0096] In the example shown in FIG. 5, it is preferable that the protective member 101 is made of Kovar and the frame member 104 is made of SUS403, the protective member 101 is made of titanium and the frame member 104 is made of SUS309S, the protective member 101 is made of titanium and the frame member 104 is made of SUS403, the protective member 101 is made of SUS403 and the frame member 104 is made of SUS309S, or the protective member 101 is made of SUS403 and the frame member 104 is made of SUS403.

[0097] Among these combinations, a combination in which the protective member 101 is made of Kovar and the frame member 104 is made of SUS403 is more preferable, as this combination has a small difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the chip plate 102, and a small difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the frame member 104.

[0098] As described above, according to the first embodiment, even if there is a difference between the linear expansion coefficient of the protective member 101 and the linear expansion coefficient of the chip plate 102, forces such as compressive force, tensile force, or shear force that occur when joining the protective member 101 and the chip plate 102 are reduced, and cracking of the chip plate 102 is suppressed.

[0099] Furthermore, the bonding area of ​​the protective member 101 with the chip plate 102 is reduced in the edge region RD where compressive, tensile, or shear forces are highest. This reduces the area of ​​the adhesive member 103 at the interface between the protective member 101 and the chip plate 102. In the edge region RD, where the effect of the difference in linear expansion coefficients is greatest, the bonding area of ​​the adhesive member 103 is reduced, reducing the mutual influence of the protective member 101 and the chip plate 102, thereby suppressing cracking of the chip plate 102. Furthermore, because the central region RC, which is less susceptible to the effect of the difference in linear expansion coefficients, has the same shape as the comparative example, the overall adhesion of the protective member 101 is ensured, and peeling between the protective member 101 and the adhesive member 103 and between the chip plate 102 and the adhesive member 103 can be suppressed.

[0100] Furthermore, cracking and peeling of the chip plate 102 due to differences in linear expansion coefficients can be suppressed, which results in the ability to select a material with a large linear expansion coefficient for the protective member 101, thereby broadening the range of material options. Furthermore, since a material with a large linear expansion coefficient can be selected for the protective member 101, the range of options for the material of the frame member 104 joined to the protective member 101 is also broadened. The frame member 104 is a relatively large member of the liquid ejection head 100, and therefore has a significant impact on cost and weight. Therefore, broadening the range of options for the material of the frame member 104 allows for reductions in cost and weight of the entire liquid ejection head 100.

[0101] [Second embodiment] A liquid ejection head according to a second embodiment will now be described. Hereinafter, elements with the same reference symbols as those in the first embodiment will be assumed to have substantially the same configurations and functions as those described in the first embodiment unless otherwise specified, and differences from the first embodiment will be mainly described. Fig. 6(a) is a schematic plan view of a liquid ejection head 100 according to a second embodiment. Fig. 6(a) schematically illustrates the liquid ejection head 100 as viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 hidden by the protective member 101 are illustrated by dashed lines for convenience, as in Fig. 2(b).

[0102] In the second embodiment, the shape of the inner peripheral edge 111 of the protective member 101 is different from that in the first embodiment. In the second embodiment, the configuration of the side S2 of the protective member 101 is also such that the joint width at the end is smaller than the joint width at the center, similar to the configuration of the side S1.

[0103] 6(b) is a schematic plan view of the bonding region R0 of the chip plate 102 and the protective member 101 according to the second embodiment. The bonding region R0 of the protective member 101 is a part of the protective member 101, and is a region of the protective member 101 that overlaps with a part of the chip plate 102 in the Z direction. That is, FIG. 6(b) illustrates the bonding region R0 of the protective member 101 that is bonded to a part of the chip plate 102.

[0104] As described in the first embodiment, the nozzle surface 121 has four sides S1 to S4. Side S2 is an example of a second side. Side S2 is a side that extends in the X direction and includes two ends E3 and E4 in the X direction and a center C2 in the X direction. The center C2 is the center in the X direction between ends E3 and E4.

[0105] The following description focuses on two positions P4 and P5 on side S2. Position P4 is an example of the fourth position, and position P5 is an example of the fifth position. Edge E3 is an example of the third edge. Edge E4 is an example of the fourth edge. Edge E4 is the edge of side S2 opposite edge E3. Of the two positions P4 and P5, position P4 is closer to edge E3 of side S2 than position P5. In the second embodiment, position P5 is located at the center C2 of side S2. Each of edges E3 and E4 is one of the four corners of the nozzle surface 121.

[0106] In the Y direction, which is parallel to the nozzle surface 121 and perpendicular to the side S2, the shortest distance from the position P4 to the inner circumferential edge 111 of the protective member 101 is defined as L4. The shortest distance L4 is a linear distance in the Y direction. Furthermore, in the Y direction, the shortest distance from the position P5 to the inner circumferential edge 111 of the protective member 101 is defined as L5. The shortest distance L5 is a linear distance in the Y direction. The shortest distance L4 is an example of a fourth shortest distance. The shortest distance L5 is an example of a fifth shortest distance. The position P4 is the position with the shortest distance to the inner circumferential edge 111 among multiple positions on the side S2 toward the end E3 with respect to the center C2. The position P5 is the position with the longest shortest distance to the inner circumferential edge 111 among multiple positions on the side S2. The shortest distance L4 is shorter than the shortest distance L5. This prevents the chip plate 102 from cracking, even in the end region on the end E3 side.

[0107] The shortest distance L4 is preferably 10% to 80% of the shortest distance L5. That is, it is preferable that 0.1≦(L4 / L5)≦0.8. This effectively prevents cracking of the chip plate 102 and peeling of the adhesive member 103, even in the end region on the edge E3 side.

[0108] Next, the following description focuses on two positions P5 and P6 on side S2. Position P6 is an example of a sixth position. Of the two positions P5 and P6, position P6 is closer to end E4 of side S2 than position P5.

[0109] In the Y direction, which is parallel to the nozzle surface 121 and perpendicular to the side S2, the shortest distance from the position P6 to the inner peripheral edge 111 of the protective member 101 is defined as L6. The shortest distance L6 is a linear distance in the Y direction. The shortest distance L6 is an example of a sixth shortest distance. Among multiple positions on the side S2 toward the end E4 with respect to the center C2, the position P6 is the position with the shortest shortest distance to the inner peripheral edge 111. The shortest distance L6 is smaller than the shortest distance L5. That is, the width of the longitudinal end of the bonding region R0 is narrower than the width of the longitudinal center of the bonding region R0, and the width of the lateral end of the bonding region R0 is narrower than the width of the lateral center of the bonding region R0. This effectively prevents the chip plate 102 from cracking, even in the end region on the side of the end E4 opposite the end E3.

[0110] The shortest distance L6 is preferably 10% to 80% of the shortest distance L5. That is, it is preferable that 0.1≦(L6 / L5)≦0.8. This effectively prevents cracking of the chip plate 102 and peeling of the adhesive member 103, even in the end region on the side of the end E4 opposite to the end E3.

[0111] The configuration of side S2 of protective member 101 has been described above, but the present invention is not limited to this, and the configuration of side S4 of protective member 101 may be the same as the configuration of side S2. This reduces the force acting on the four corners of chip plate 102, effectively preventing chip plate 102 from cracking.

[0112] [Third embodiment] A liquid ejection head according to a third embodiment will now be described. Hereinafter, elements with the same reference symbols as those in the first or second embodiment will be assumed to have substantially the same configurations and functions as those described in the first or second embodiment unless otherwise specified, and differences from the first and second embodiments will be mainly described. Fig. 7(a) is a schematic plan view of a liquid ejection head 100 according to a third embodiment. Fig. 7(a) shows a schematic view of the liquid ejection head 100 as viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 hidden by the protective member 101 are shown by dashed lines for convenience, as in Fig. 2(b).

[0113] The shape of the protective member 101 of the third embodiment is similar to the shape of the protective member 101 of the second embodiment, but in the third embodiment, the surface roughness of one part of the protective member 101 is greater than the surface roughness of the other part.

[0114] The bonding region R0 of the protective member 101 has a bonding surface 112 that faces the nozzle surface 121 and is bonded to the nozzle surface 121. The bonding surface 112 is an example of a first surface. The bonding surface 112 has portions B1 to B4 that overlap with the four corners of the nozzle surface 121 in the Z direction perpendicular to the nozzle surface 121. The portions B1 to B4 do not overlap with the centers of the sides S1 to S4 of the nozzle surface 121 in the Z direction. The bonding surface 112 also has a portion B5 other than the portions B1 to B4. The portion B5 overlaps with a position P2 in the Z direction. The portion B5 also overlaps with the centers of the sides S1 to S4 of the nozzle surface 121 in the Z direction. The portion B1 is an example of a first portion, and the portion B5 is an example of a second portion. The surface roughness of the portions B1 to B4 is greater than that of the portion B5. This increases the adhesive strength between the adhesive member 103 and the portions B1 to B4 on the joining surface 112.

[0115] [Fourth embodiment] A liquid ejection head according to a fourth embodiment will now be described. Hereinafter, elements with the same reference symbols as those in the first, second, or third embodiment will be assumed to have substantially the same configurations and functions as those described in the first, second, or third embodiment unless otherwise specified, and differences from the first, second, and third embodiments will be mainly described. Fig. 7(b) is a schematic plan view of a liquid ejection head 100 according to a fourth embodiment. Fig. 7(b) shows a schematic view of the liquid ejection head 100 as viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 hidden by the protective member 101 are shown by dashed lines for convenience, as in Fig. 2(b).

[0116] In the first embodiment, the width of the bonding region R0 is L2 only at the center C1 on the side S1, but this is not limited to this. In the fourth embodiment, a section D2 in the Y direction of the bonding region R0 of a predetermined length that includes the center C1 on the side S1 has the width L2. In other words, the inner peripheral edge 111 of the protective member 101 has a straight line portion parallel to the side S1 whose distance in the X direction from the side S1 is L2.

[0117] According to the fourth embodiment, the bonding region R0 has a long section D2 in the Y direction with a width L2, which can suppress cracking at the end of the chip plate 102, and further improves the adhesion between the protective member 101 and the adhesive member 103, and the adhesion between the chip plate 102 and the adhesive member 103.

[0118] [Fifth embodiment] A liquid ejection head according to a fifth embodiment will be described. Hereinafter, elements with the same reference symbols as those in the first, second, third, or fourth embodiment will have substantially the same configurations and functions as those described in the first, second, third, or fourth embodiment unless otherwise specified, and differences from the first, second, third, and fourth embodiments will be mainly described. Fig. 7(c) is a schematic plan view of a liquid ejection head 100 according to a fifth embodiment. Fig. 7(c) shows a schematic view of the liquid ejection head 100 as viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 hidden by the protective member 101 are shown by dashed lines for convenience, as in Fig. 2(b).

[0119] While the protective member 101 of the first embodiment has been described as being formed in an opening shape that entirely surrounds the plurality of nozzle holes 120, the protective member 101 of the fifth embodiment has a bridging structure in which a plurality of bridging members 113 connect both short sides of the opening. The plurality of bridging members 113 are arranged between the plurality of nozzle rows. That is, each of the plurality of nozzle rows is surrounded by the protective member 101. Each nozzle row is composed of two or more nozzle holes 120 arranged in the Y direction. The plurality of nozzle rows are arranged at intervals from each other in the X direction. According to the fifth embodiment, the plurality of nozzle holes 120 are surrounded by the protective member 101 for each nozzle row, thereby improving nozzle protection performance.

[0120] [Variation 1] Modification 1 is a modification of the liquid ejection head 100 of the second embodiment. Fig. 8(a) is a schematic plan view of the liquid ejection head 100 according to Modification 1. Fig. 8(a) schematically illustrates the liquid ejection head 100 as viewed in the negative direction of the Z axis, and the portions of the liquid ejection head 100 that are hidden by the protective member 101 are illustrated by dashed lines for convenience, similar to Fig. 2(b).

[0121] In the second embodiment, as shown in Figures 6(a) and 6(b), the bonding region R0 is formed so that the bonding width narrows linearly from the center C1 toward the end. In Modification 1, as shown in Figure 8(a), when viewed in the Z direction, the bonding region R0 of the protective member 101, i.e., the inner peripheral edge 111 of the protective member 101, has an arc-shaped portion facing each of the sides S1 to S4. By making the inner peripheral edge 111 arc-shaped, it is possible to reduce the force generated at the end of the chip plate 102 and increase the overall bonding area of ​​the bonding region R0, thereby ensuring high adhesion.

[0122] [Variation 2] Modification 2 is a modification of the liquid ejection head 100 of the fourth embodiment. Fig. 8(b) is a schematic plan view of the liquid ejection head 100 according to Modification 2. Fig. 8(b) schematically illustrates the liquid ejection head 100 as viewed in the negative direction of the Z axis, and the portions of the liquid ejection head 100 that are hidden by the protective member 101 are illustrated by dashed lines for convenience, similar to Fig. 2(b).

[0123] In the fourth embodiment, as shown in Fig. 7(b), a section D2 in the Y direction of the bonding region R0 including the center C1 of the side S1 has a width L2, and the width gradually narrows from section D2 toward the end, as shown in Fig. 7(b). However, this is not limited to this. For example, as shown in Fig. 8(b), a section D2 in the Y direction of the bonding region R0 including the center C1 of the side S1 may have a width L2, and a section D1 in the Y direction of the bonding region R0 including the position P1 of the side S1 may have a width L1. In other words, the inner peripheral edge 111 of the protective member 101 may have a straight line portion parallel to the side S1, the distance from the side S1 in the X direction being L1.

[0124] [Variation 3] Modification 3 is another modification of the liquid ejection head 100 of the fourth embodiment. Fig. 8(c) is a schematic plan view of the liquid ejection head 100 according to Modification 3. Fig. 8(c) schematically illustrates the liquid ejection head 100 as viewed in the negative direction of the Z axis, and portions of the liquid ejection head 100 that are hidden by the protective member 101 are illustrated by dashed lines for convenience, similar to Fig. 2(b).

[0125] Similar to the fourth embodiment, the protective member 101 in the third modification has a section D2 including a center C1, ensuring sufficient adhesive strength. In the end region, the inner peripheral edge 111 is formed in an arc shape. This effectively reduces the bonding area at the four corners of the chip plate 102.

[0126] [Example] Examples 1 to 11 and Comparative Example 1 showing experimental results will be described below. FIG. 9 is a table showing experimental results according to the examples. In the results section shown in FIG. 9, cases where no cracks occurred in the chip plate 102 are indicated by "A," and cases where cracks occurred in the chip plate 102 are indicated by "B." In addition, in the results section shown in FIG. 9, cases where the protective member 101 did not peel off from the chip plate 102 are indicated by "A," and cases where the protective member 101 peeled off from the chip plate 102 are indicated by "B." In addition, in the results section shown in FIG. 9, cases where the protective member 101 did not peel off from the frame member 104 are indicated by "A," and cases where the protective member 101 peeled off from the frame member 104 are indicated by "B."

[0127] Example 1 A description will be given of Example 1 corresponding to the first embodiment. In Example 1, the liquid ejection head 100 shown in Figures 2(a) to 2(c) was manufactured.

[0128] First, a titanium plate was prepared and subjected to photolithographic etching to produce a titanium protective member 101 having the shape shown in Figures 2(a) to 2(c). The thickness of the protective member 101 was set to 75 µm in consideration of shape stability. L1 / L2 and L3 / L2 were set to 0.1. Here, the linear expansion coefficient of titanium is 8.6 ppm / °C.

[0129] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0130] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0131] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0132] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0133] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0134] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0135] Example 2 A description will be given of Example 2 corresponding to the second embodiment. In Example 2, the liquid ejection head 100 shown in Figures 6(a) and 6(b) was manufactured.

[0136] First, a titanium plate was prepared and subjected to photolithographic etching to produce a titanium protective member 101 having the shape shown in Figures 6(a) and 6(b). The thickness of the protective member 101 was set to 90 µm in consideration of shape stability. L1 / L2, L3 / L2, L4 / L5, and L6 / L5 were set to 0.5. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0137] Also, an assembly was prepared in which a frame member 104 made of SUS403 was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS403 is 9.9 ppm / °C.

[0138] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a bisphenol-type thermosetting epoxy resin with a naphthalene skeleton. The protective member 101 with the adhesive applied was sucked with a suction pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0139] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0140] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0141] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0142] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0143] Example 3 A description will be given of Example 3 corresponding to the first embodiment. In Example 3, the liquid ejection head 100 shown in Figures 2(a) to 2(c) was manufactured.

[0144] First, a kovar plate was prepared and then photolithographically etched to produce the kovar protective member 101 shown in Figures 2(a) to 2(c). The thickness of the protective member 101 was set to 50 μm in consideration of shape stability. L1 / L2 and L3 / L2 were set to 0.8. The linear expansion coefficient of kovar is 5.2 ppm / °C.

[0145] Also, an assembly was prepared in which a frame member 104 made of SUS403 was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS403 is 9.9 ppm / °C.

[0146] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a thermosetting epoxy resin whose main structure was bisphenol A and bisphenol F, to which silica particles with a particle size of 10 μm had been added. The protective member 101 to which the adhesive had been applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102. After that, while being aligned with an alignment device, a pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. Thereafter, the adhesive was heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0147] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 5 μm, and that they were joined with high precision.

[0148] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0149] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0150] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0151] Example 4 A description will be given of Example 4 corresponding to the third embodiment. In Example 4, the liquid ejection head 100 shown in Fig. 7(a) was manufactured.

[0152] First, a plate made of SUS403 was prepared and then etched using photolithography to produce the protective member 101 made of SUS403 shown in Figure 7(a). The thickness of the protective member 101 was set to 90 μm to ensure stability of the shape. L1 / L2 (L3 / L2, L4 / L5, L6 / L5) was set to 0.1. The linear expansion coefficient of SUS403 is 9.9 ppm / °C.

[0153] Finally, as shown in FIG. 7(a), the four corners B1 to B4 of the bonding surface 112 of the protection member 101 were roughened by sandblasting to improve the adhesion of the adhesive member 103 at these portions B1 to B4.

[0154] Also, an assembly was prepared in which a frame member 104 made of SUS403 was fixed with screws 107 to a base 106 on which a chip plate 102 made of silicon was attached.

[0155] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a bisphenol-type thermosetting epoxy resin with a naphthalene skeleton. The protective member 101 with the adhesive applied was sucked with a suction pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0156] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0157] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0158] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0159] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0160] Example 5 A description will be given of Example 5 corresponding to the fourth embodiment. In Example 5, the liquid ejection head 100 shown in Fig. 7(b) was manufactured.

[0161] First, a titanium plate was prepared and then photolithographically etched to produce a titanium protective member 101 with the shape shown in Figure 7(b). The thickness of the protective member 101 was set to 75 μm to ensure stability of the shape. L1 / L2 (L3 / L2) was set to 0.5. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0162] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0163] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0164] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0165] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0166] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0167] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0168] Example 6 A description will be given of Example 6 corresponding to the fifth embodiment. In Example 6, the liquid ejection head 100 shown in Fig. 7(c) was manufactured.

[0169] First, a titanium plate was prepared and then photolithographically etched to produce a titanium protective member 101 with the shape shown in Figure 7(c). The thickness of the protective member 101 was set to 90 μm to ensure stability of the shape. L1 / L2 (L3 / L2) was set to 0.5. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0170] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0171] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0172] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0173] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0174] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0175] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0176] Example 7 A description will be given of Example 7 corresponding to Modification 1. In Example 7, the liquid ejection head 100 shown in Fig. 8(a) was manufactured.

[0177] First, a titanium plate was prepared and then photolithographically etched to produce a titanium protective member 101 with the shape shown in Figure 8(a). The thickness of the protective member 101 was set to 75 μm to ensure stability of the shape. L1 / L2 (L3 / L2, L4 / L5, L6 / L5) was set to 0.5. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0178] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0179] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0180] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 5 μm, and that they were joined with high precision.

[0181] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0182] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0183] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0184] Example 8 A description will be given of Example 8 corresponding to Modification 2. In Example 8, the liquid ejection head 100 shown in Fig. 8(b) was manufactured.

[0185] First, a titanium plate was prepared and then photolithographically etched to produce a titanium protective member 101 with the shape shown in Figure 8(b). The thickness of the protective member 101 was set to 90 μm to ensure stability of the shape. L1 / L2, L3 / L2, L4 / L5, and L6 / L5 were set to 0.25. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0186] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0187] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0188] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 5 μm, and that they were joined with high precision.

[0189] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0190] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0191] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0192] Example 9 A description will be given of Example 9 corresponding to Modification 3. In Example 9, the liquid ejection head 100 shown in Fig. 8(c) was manufactured.

[0193] First, a titanium plate was prepared and then photolithographically etched to produce a titanium protective member 101 with the shape shown in Figure 8(b). The thickness of the protective member 101 was set to 90 μm to ensure stability of the shape. L1 / L2 (L3 / L2, L4 / L5, L6 / L5) was set to 0.25. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0194] Next, an assembly was prepared in which a frame member 104 made of SUS309S was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS309S is 14.4 ppm / °C.

[0195] Next, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The protective member 101 with the adhesive applied was adsorbed with an adsorption pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0196] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 5 μm, and that they were joined with high precision.

[0197] No cracks were found in the chip plate 102. Furthermore, an ultrasonic microscope was used to observe whether peeling or voids occurred in the bonded region, but no defects were found.

[0198] Furthermore, the chip plate 102 of the liquid ejection head 100 was immersed in ink, and then taken out and observed under a microscope. As a result, it was confirmed that there was no problem with the sealing performance.

[0199] Finally, the liquid ejection head 100 was set in the liquid ejection device 1 and a liquid ejection test was performed, which confirmed that there were no problems with the liquid ejection performance. After that, a recovery operation was performed 100 times using a wiper, and the liquid ejection after the recovery operation was also stable.

[0200] Example 10 A description will be given of Example 10 corresponding to the second embodiment. In Example 10, the liquid ejection head 100 shown in Figures 6(a) and 6(b) was manufactured.

[0201] First, a titanium plate was prepared and subjected to photolithographic etching to produce a titanium protective member 101 having the shape shown in Figures 6(a) and 6(b). The thickness of the protective member 101 was set to 90 μm to ensure stability of the shape. L1 / L2, L3 / L2, L4 / L5, and L6 / L5 were set to 0.08. The linear expansion coefficient of titanium is 8.6 ppm / °C.

[0202] Also, an assembly was prepared in which a frame member 104 made of SUS403 was fixed with screws 107 to a base 106 on which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of SUS403 is 9.9 ppm / °C.

[0203] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a bisphenol-type thermosetting epoxy resin with a naphthalene skeleton. The protective member 101 with the adhesive applied was sucked with a suction pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0204] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 5 μm, and that they were joined with high precision.

[0205] No cracks were found in the chip plate 102. An ultrasonic microscope was also used to observe the bonding area for peeling or voids, but no defects were found. However, when the chip plate 102 of the liquid ejection head 100 was immersed in ink, then removed and observed under a microscope, it was confirmed that ink had passed through the gap 109 and adhered to the flexible flat cable 105. It is believed that peeling had occurred in a microscopic area that could not be observed with the ultrasonic microscope.

[0206] Example 11 An explanation will be given of Example 11 corresponding to the first embodiment. In Example 11, the liquid ejection head 100 shown in Figures 2(a) to 2(c) was manufactured.

[0207] First, a Kovar plate was prepared and subjected to photolithographic etching to produce a Kovar protective member 101 having the shape shown in Figures 2(a) to 2(c). The thickness of the protective member 101 was set to 50 μm in consideration of shape stability. L1 / L2 and L3 / L2 were set to 0.8. The linear expansion coefficient of Kovar is 5.2 ppm / °C.

[0208] From the viewpoint of light weight and cost, aluminum was used as the material for the frame member 104. An assembly was prepared in which the aluminum frame member 104 was fixed with screws 107 to a base 106 to which a silicon chip plate 102 was attached. Here, the linear expansion coefficient of aluminum is 24.0 ppm / °C.

[0209] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a bisphenol-type thermosetting epoxy resin with a naphthalene skeleton. The protective member 101 with the adhesive applied was sucked with a suction pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0210] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0211] No cracks were found in the chip plate 102. However, when an ultrasonic microscope was used to observe the bonding area for peeling or voids, it was confirmed that some peeling had occurred at the interface between the protective member 101 and the frame member 104.

[0212] Example 12 A description will be given of Example 12 corresponding to the third embodiment. In Example 12, the liquid ejection head 100 shown in Fig. 7(a) was manufactured.

[0213] First, as in Example 4, a SUS403 plate was prepared and then photolithographically etched to produce a SUS403 protective member 101 as shown in FIG. 7(a). The thickness of the protective member 101 was set to 90 μm to ensure shape stability. L1 / L2 (L3 / L2, L4 / L5, L6 / L5) was set to 0.1. The linear expansion coefficient of SUS403 is 9.9 ppm / °C.

[0214] In Example 4, the four corners of the joining surface 112 of the protection member 101 were roughened by sandblasting, but in Example 12, sandblasting was not performed.

[0215] Similarly to Example 4, an assembly was prepared in which a frame member 104 made of SUS403 was fixed with screws 107 to a base 106 on which a chip plate 102 made of silicon was attached.

[0216] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering Co., Ltd.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101. The adhesive used was a bisphenol-type thermosetting epoxy resin with a naphthalene skeleton. The protective member 101 with the adhesive applied was sucked with a suction pad and placed in a predetermined position on the chip plate 102, and then, while being aligned with an alignment device, pressure of 1 kgf was applied from above to spread the adhesive evenly over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, and the liquid ejection head 100 was fabricated.

[0217] After removing the liquid ejection head 100 from the oven, the positional relationship between the chip plate 102 and the protective member 101 was checked using a microscope, and it was confirmed that the deviation from the alignment mark was less than 10 μm, and that they were joined with high precision.

[0218] No cracks were found in the chip plate 102. An ultrasonic microscope was also used to observe the bonding area for peeling or voids, but no defects were found. However, when the chip plate 102 of the liquid ejection head 100 was immersed in ink, then removed and observed under a microscope, it was confirmed that ink had passed through the gap 109 and adhered to the flexible flat cable 105. It is believed that peeling had occurred in a microscopic area that could not be observed with the ultrasonic microscope.

[0219] (Comparative Example 1) A description will be given of Comparative Example 1, which corresponds to the comparative example. In Comparative Example 1, a liquid ejection head 100X shown in Figures 3(a) to 3(c) was manufactured.

[0220] First, a titanium plate was prepared and subjected to photolithographic etching to produce a titanium protective member 101X having the shape shown in Figures 3(a) to 3(c). The thickness of the protective member 101 was set to 50 μm to ensure stability of the shape. Since there was no change in the bonding width, L1 / L2 was 1.0. Here, the linear expansion coefficient of titanium was 8.6 ppm / °C.

[0221] An assembly was also prepared in which an alumina frame member 104X was fixed with screws to a base on which a silicon chip plate 102X was attached. The linear expansion coefficient of alumina is 7.7 ppm / °C.

[0222] Next, as in Example 1, a dispenser (manufactured by Musashi Engineering, Inc.) was used to apply a predetermined amount of adhesive to a predetermined position on the protective member 101X. A bisphenol-type thermosetting epoxy resin with a naphthalene skeleton was used as the adhesive. The adhesive-coated protective member 101X was then sucked with a suction pad and placed in a predetermined position on the chip plate 102X. After that, while being aligned with an alignment device, pressure of 1 kgf was applied from above to evenly spread the adhesive over the bonding area. The adhesive was then heated in an oven at 120°C for 1 hour to harden the adhesive, thereby producing the liquid ejection head 100X.

[0223] After removing the liquid ejection head 100X from the oven, it was observed under a microscope and it was confirmed that a crack had occurred at the edge of the tip plate 102X. Because a crack had occurred in the tip plate 102X, further evaluation was not carried out.

[0224] [Embodiment of manufacturing method of article] In this embodiment, an article is manufactured using the liquid ejection device described above. The article may be an intermediate product or a final product. The article manufacturing method according to this embodiment is suitable for manufacturing an article such as an organic light-emitting diode (OLED) panel using a liquid ejection device. The article manufacturing method according to this embodiment includes a step (coating step) of depositing or applying a solution film (a solution containing a solute and a solvent for forming an organic film) on a substrate by a printing method or the like using a liquid ejection device to obtain a coated substrate. The method also includes a step (drying step) of drying the solution film on the coated substrate to obtain a dry substrate on which a dry film has been formed. Furthermore, this manufacturing method includes other well-known steps (such as baking, cooling, dehumidification, dry cleaning, electrode formation, and sealing film formation). The article manufacturing method according to this embodiment is advantageous over conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

[0225] The present disclosure is not limited to the above-described embodiments, and many modifications of the embodiments are possible within the technical concept of the present disclosure. Furthermore, the effects described in the present embodiments are merely a list of the most preferable effects resulting from the embodiments of the present disclosure, and the effects of the embodiments of the present disclosure are not limited to those described in the present embodiments.

[0226] The disclosure of the above embodiments includes the following sections.

[0227] (Section 1) a plate having a nozzle surface including nozzle holes for ejecting liquid; a frame-shaped first member that is fixed to a part of the nozzle surface with an adhesive member and is formed so as not to overlap the nozzle hole in a direction perpendicular to the nozzle surface, the first member has a linear expansion coefficient greater than that of the plate; of a first position and a second position on a first side of the nozzle face, the first position is closer to a first end of the first side than the second position; a first shortest distance from the first position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than a second shortest distance from the second position to the inner circumferential edge of the first member; A liquid ejection head characterized by:

[0228] (Section 2) The first shortest distance is 10% or more and 80% or less of the second shortest distance. Item 1. A liquid ejection head according to item 1.

[0229] (Section 3) Of the second position and the third position on the first side, the third position is closer to a second end of the first side than the second position; a third shortest distance from the third position to the inner peripheral edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than the second shortest distance; 3. The liquid ejection head according to item 1 or 2, characterized in that:

[0230] (Section 4) The third shortest distance is 10% or more and 80% or less of the second shortest distance. Item 4. A liquid ejection head according to item 3, characterized in that:

[0231] (Section 5) The second position is a center position of the first side. 5. The liquid ejection head according to any one of items 1 to 4, characterized in that:

[0232] (Section 6) a second side of the nozzle surface intersects with the first side, Of a fourth position and a fifth position on the second side, the fourth position is closer to a third end of the second side than the fifth position; a fourth shortest distance from the fourth position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the second side is shorter than a fifth shortest distance from the fifth position to the inner circumferential edge of the first member; 6. The liquid ejection head according to any one of items 1 to 5, characterized in that:

[0233] (Section 7) The fourth shortest distance is 10% or more and 80% or less of the fifth shortest distance. Item 7. A liquid ejection head according to item 6, characterized in that:

[0234] (Section 8) Of the fifth position and the sixth position on the second side, the sixth position is closer to a fourth end of the second side than the fifth position; a sixth shortest distance from the sixth position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the second side is shorter than a fifth shortest distance from the fifth position to the inner circumferential edge of the first member; Item 8. The liquid ejection head according to item 6 or 7, characterized in that:

[0235] (Section 9) The sixth shortest distance is 10% or more and 80% or less of the fifth shortest distance. Item 9. A liquid ejection head according to item 8, characterized in that:

[0236] (Section 10) The fifth position is a center position of the second side. 10. The liquid ejection head according to any one of items 6 to 9, characterized in that:

[0237] (Section 11) The first side is longer than the second side. 11. The liquid ejection head according to any one of items 6 to 10, characterized in that:

[0238] (Section 12) When viewed in a plan view from a direction perpendicular to the nozzle surface, the width of the first member near the corner is smaller than the width of the first side at the center thereof. 12. The liquid ejection head according to any one of items 1 to 11, characterized in that:

[0239] (Section 13) a first surface of the first member on the nozzle surface side has a first portion overlapping the first position in a direction perpendicular to the nozzle surface, and a second portion other than the first portion overlapping the second position in the direction perpendicular to the nozzle surface, The surface roughness of the first portion is greater than the surface roughness of the second portion. 13. The liquid ejection head according to any one of items 1 to 12, characterized in that:

[0240] (Section 14) Further provided is a second member surrounding the outer periphery of the plate, the first member is disposed so as to overlap the plate and the second member in a direction perpendicular to the nozzle surface, and is fixed to the plate and the second member; 14. The liquid ejection head according to any one of items 1 to 13, characterized in that

[0241] (Section 15) The difference between the linear expansion coefficient of the first member and the linear expansion coefficient of the second member is 6 ppm / °C or less. Item 15. A liquid ejection head according to item 14, characterized in that:

[0242] (Section 16) The first member is mainly composed of metal. 16. The liquid ejection head according to any one of items 1 to 15,

[0243] (Section 17) The main component of the first member is invar, kovar, titanium, or stainless steel. Item 17. A liquid ejection head according to item 16, characterized in that:

[0244] (Section 18) The second member is mainly composed of metal. Item 16. A liquid ejection head according to item 14 or 15.

[0245] (Section 19) The main component of the second member is invar, kovar, titanium, aluminum or stainless steel. Item 19. A liquid ejection head according to item 18, characterized in that:

[0246] (Section 20) A liquid ejection head according to any one of items 1 to 19, a tank for supplying liquid to the liquid ejection head, A liquid ejection device characterized by:

[0247] (Section 21) Item 19: Using the liquid ejection head according to any one of items 1 to 19, a liquid containing a material for manufacturing an article is ejected to manufacture the article. A method for manufacturing an article.

[0248] (Section 22) A method for manufacturing a liquid ejection head, comprising: A step of preparing a plate having a nozzle surface including nozzle holes for ejecting liquid, and a frame-shaped first member; applying an adhesive to at least one of the plate and the first member; a step of aligning the plate and the first member with the adhesive sandwiched between them so that the nozzle holes do not overlap the first member in a direction perpendicular to the nozzle surface; and a step of fixing the plate and the first member by hardening the adhesive, the first member has a linear expansion coefficient greater than that of the plate; of a first position and a second position on a first side of the nozzle face, the first position is closer to a first end of the first side than the second position; after the adhesive is hardened, a first shortest distance from the first position to an inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than a second shortest distance from the second position to the inner circumferential edge of the first member; A method for manufacturing a liquid ejection head, comprising: [Explanation of symbols]

[0249] E1...edge (first edge), E2...edge (second edge), L1...shortest distance (first shortest distance), L2...shortest distance (second shortest distance), P1...position (first position), P2...position (second position), S1...side (first side), S2...side (second side), 1...liquid ejection device, 100...liquid ejection head, 101...protective member (first member), 102...chip plate, 103...adhesive member, 104...frame member (second member), 120...nozzle hole, 121...nozzle surface

Claims

1. a plate having a nozzle surface including nozzle holes for ejecting liquid; a frame-shaped first member that is fixed to a part of the nozzle surface with an adhesive member and is formed so as not to overlap the nozzle hole in a direction perpendicular to the nozzle surface, the first member has a linear expansion coefficient greater than that of the plate; of a first position and a second position on a first side of the nozzle face, the first position is closer to a first end of the first side than the second position; a first shortest distance from the first position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than a second shortest distance from the second position to the inner circumferential edge of the first member; A liquid ejection head characterized by:

2. the first shortest distance is 10% or more and 80% or less of the second shortest distance; 2. The liquid ejection head according to claim 1.

3. of the second position and the third position on the first side, the third position is closer to a second end of the first side than the second position; a third shortest distance from the third position to the inner peripheral edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than the second shortest distance; 2. The liquid ejection head according to claim 1.

4. the third shortest distance is 10% or more and 80% or less of the second shortest distance; 4. The liquid ejection head according to claim 3.

5. The second position is a center position of the first side.

2. The liquid ejection head according to claim 1.

6. a second side of the nozzle face intersects with the first side, Of a fourth position and a fifth position on the second side, the fourth position is closer to a third end of the second side than the fifth position; a fourth shortest distance from the fourth position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the second side is shorter than a fifth shortest distance from the fifth position to the inner circumferential edge of the first member; 2. The liquid ejection head according to claim 1.

7. the fourth shortest distance is 10% or more and 80% or less of the fifth shortest distance; 7. A liquid ejection head according to claim 6.

8. Of the fifth position and the sixth position on the second side, the sixth position is closer to a fourth end of the second side than the fifth position; a sixth shortest distance from the sixth position to the inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the second side is shorter than a fifth shortest distance from the fifth position to the inner circumferential edge of the first member; 7. A liquid ejection head according to claim 6.

9. the sixth shortest distance is 10% or more and 80% or less of the fifth shortest distance; 9. The liquid ejection head according to claim 8.

10. the fifth position is a center position of the second side; 7. A liquid ejection head according to claim 6.

11. The first side is longer than the second side.

7. A liquid ejection head according to claim 6.

12. When viewed in a plan view from a direction perpendicular to the nozzle surface, the width of the first member near the corner is smaller than the width of the first side at a center position.

2. The liquid ejection head according to claim 1.

13. a first surface of the first member on the nozzle surface side has a first portion overlapping the first position in a direction perpendicular to the nozzle surface, and a second portion other than the first portion overlapping the second position in the direction perpendicular to the nozzle surface, The surface roughness of the first portion is greater than the surface roughness of the second portion.

2. The liquid ejection head according to claim 1.

14. Further provided is a second member surrounding the outer periphery of the plate, the first member is disposed so as to overlap the plate and the second member in a direction perpendicular to the nozzle surface, and is fixed to the plate and the second member; 2. The liquid ejection head according to claim 1.

15. a difference between the linear expansion coefficient of the first member and the linear expansion coefficient of the second member is 6 ppm / °C or less; 15. The liquid ejection head according to claim 14.

16. The first member is mainly composed of metal.

2. The liquid ejection head according to claim 1.

17. The main component of the first member is invar, kovar, titanium, or stainless steel.

17. The liquid ejection head according to claim 16.

18. The second member is mainly composed of metal.

15. The liquid ejection head according to claim 14.

19. The main component of the second member is invar, kovar, titanium, aluminum or stainless steel.

19. The liquid ejection head according to claim 18.

20. A liquid ejection head according to any one of claims 1 to 19, a tank for supplying liquid to the liquid ejection head, A liquid ejection device characterized by:

21. 20. An article is manufactured by discharging a liquid containing a material for manufacturing the article using the liquid discharge head according to any one of claims 1 to 19. A method for manufacturing an article.

22. A method for manufacturing a liquid ejection head, comprising: A step of preparing a plate having a nozzle surface including nozzle holes for ejecting liquid, and a frame-shaped first member; applying adhesive to at least one of the plate and the first member; a step of positioning the plate and the first member with the adhesive sandwiched between them so that the nozzle holes do not overlap the first member in a direction perpendicular to the nozzle surface; and a step of fixing the plate and the first member by hardening the adhesive, the first member has a linear expansion coefficient greater than that of the plate; of a first position and a second position on a first side of the nozzle face, the first position is closer to a first end of the first side than the second position; after the adhesive is hardened, a first shortest distance from the first position to an inner circumferential edge of the first member in a direction parallel to the nozzle surface and perpendicular to the first side is shorter than a second shortest distance from the second position to the inner circumferential edge of the first member; A method for manufacturing a liquid ejection head, comprising:

Images