Inkjet head, method for manufacturing the same, method for manufacturing semiconductor device using the inkjet head, and printing apparatus

Abstract

The present disclosure provides an inkjet head capable of continuously ejecting droplets at a high frequency even when an ink having a high viscosity is used. The present disclosure relates to an inkjet head including a nozzle plate portion (10) in which a nozzle (11) that ejects a droplet is formed, a vibrating plate (31, 33) disposed opposite an inlet of the nozzle (11), a weight (34) disposed in contact with the vibrating plate (31), and an actuator (50) that abuts against the weight (34), wherein the weight (34) is caused to fly by driving the actuator (50) in accordance with a drive signal, and ink inside an ink chamber (60) formed between the nozzle plate portion (10) and the vibrating plate (31, 33) is ejected from the nozzle (11), and wherein a housing chamber (70) in which the actuator (50) is disposed is configured to be separated from the ink chamber (60) by the vibrating plate (31, 33).

Description

Technical Field

[0001] This invention relates to an inkjet head, a method for manufacturing an inkjet head, a method for manufacturing a semiconductor device using the inkjet head, and a printing apparatus, and particularly to an inkjet head that ejects ink using the vibration of an actuator, a method for manufacturing an inkjet head, a method for manufacturing a semiconductor device using the inkjet head, and a printing apparatus. Background Technology

[0002] Currently, inkjet technology, which ejects micro-droplets of ink, is used in image forming apparatuses to depict images on paper. In these apparatuses, the ink is adjusted to a composition and viscosity suitable for penetration into the paper to form an image. However, in recent years, there has been a growing demand for applying inkjet technology to applications beyond image formation on paper.

[0003] Applications of inkjet technology include ink coating on resins and metals, overlay coating of inks, 3D printing, and coating of droplets containing functional microparticles. In these applications, the droplets tend to have a higher viscosity than the inks used in existing inkjet printing.

[0004] In existing electrothermal inkjet technologies, the droplets are ejected by bubbles generated from film boiling due to heating, making it difficult to eject droplets with high viscosity. Furthermore, in existing electromechanical inkjet technologies, the actuator displacement is relatively small, making it difficult to transfer sufficient momentum to the droplets and impart sufficient initial velocity to the droplets ejected from the nozzle.

[0005] Therefore, in inkjet technology using electromechanical conversion, it is also proposed to transfer the momentum of the actuator via the flying body to ensure the displacement of the vibrating body that the flying body collides with, thereby improving the ejection characteristics of the droplets (see, for example, Patent Document 1).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 04-126254 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, the prior art in Patent Document 1 requires the use of non-conductive paraffin as ink, which limits its application range. Furthermore, the efficiency of converting the electrical energy applied to the actuator into the kinetic energy of the flying body is insufficient, making it difficult to stably spray ink with a viscosity higher than a few mPa·s. Moreover, if the ink viscosity increases, it becomes difficult to supply ink to the periphery of the nozzle, thus making it difficult to continuously spray ink at a high frequency of a few kHz.

[0011] Therefore, the present invention was made in view of the above-mentioned existing problems, and its object is to provide an inkjet head that can continuously eject droplets at a high frequency even when using inks with high viscosity.

[0012] Solution for solving the problem

[0013] To solve the above-mentioned problems, the inkjet head of the present invention is characterized by comprising: a nozzle plate portion having a nozzle on which droplets are ejected; a vibrating plate disposed opposite to the inlet of the nozzle; a weight disposed in contact with the vibrating plate; and an actuator abutting against the weight, wherein the actuator is driven according to a drive signal to cause the weight to fly, thereby causing ink formed in an ink chamber between the nozzle plate portion and the vibrating plate to be ejected from the nozzle. The inkjet head is characterized in that the housing chamber in which the actuator is disposed is configured to be separated from the ink chamber by the vibrating plate.

[0014] In this inkjet head of the present invention, the receiving chamber and the ink chamber are separated by a vibrating plate, allowing the actuator and counterweight to be separated from the ink without filling the receiving chamber with ink, thus enabling the use of various inks. Furthermore, it reduces the loss of kinetic energy transmitted from the actuator to the vibrating plate via the counterweight, enabling the continuous ejection of high-viscosity inks at a higher frequency.

[0015] Furthermore, in one embodiment of the present invention, the ink chamber includes an ejection region comprising the inlet of the nozzle and a storage region adjacent to the ejection region, wherein the ejection region is smaller than the storage region in terms of the gap between the nozzle plate and the vibrating plate.

[0016] Furthermore, in one aspect of the present invention, the gap in the ejection region is in the range of 1 μm or more and 50 μm or less.

[0017] Furthermore, in one embodiment of the present invention, the viscosity of the ink is in the range of 20 mPa·s or higher. Additionally, in this specification, "viscosity" refers to the viscosity value of the ink at the ink temperature when the inkjet head is operating.

[0018] Furthermore, in one embodiment of the present invention, the aforementioned vibrating plate is constructed by a laminated structure of a beam-shaped spring portion and a thin plate portion, wherein the thin plate portion is constructed of a flexible sheet material.

[0019] Furthermore, in one embodiment of the present invention, the portion of the spring portion opposite to the inlet of the nozzle is formed to be wide.

[0020] Furthermore, in one embodiment of the present invention, the aforementioned weight is spherical and is fitted and positioned within the positioning portion provided on the aforementioned spring portion.

[0021] Furthermore, in one embodiment of the present invention, the aforementioned weight is spherical and is positioned on a pedestal on the main surface of the storage chamber side of the aforementioned thin plate portion.

[0022] Furthermore, in one embodiment of the present invention, the spring portion has a protrusion on the main surface of the nozzle side facing the nozzle inlet, and the protrusion is configured to be inserted into the nozzle inlet with a gap.

[0023] Furthermore, in one embodiment of the present invention, an ink supply hole is formed through the vibrating plate, through which ink is supplied to the ink chamber.

[0024] Furthermore, in one aspect of the present invention, a combination of multiple actuators and the aforementioned counterweight is provided, and a spacer portion is disposed between the nozzle plate portion and the vibrating plate portion, the spacer portion being disposed between adjacent actuators.

[0025] Furthermore, in one embodiment of the present invention, a support member is provided to support the nozzle plate portion, and the support member is fixed to a laminated structure including the nozzle plate portion, the spacer portion, and the vibrating plate.

[0026] Furthermore, in one embodiment of the present invention, the aforementioned support member is a non-driving part integrally formed with the aforementioned actuator.

[0027] Furthermore, in one aspect of the present invention, a combination of multiple actuators and weights is provided, and a spacer portion is provided between the nozzle plate portion and the vibrating plate. The vibrating plate has a beam on the main surface of the thin plate portion on the receiving chamber side and a support column on the main surface of the thin plate portion on the ink chamber side. The beam and the support column are bonded to the thin plate portion opposite each other with a gap between adjacent multiple weights, and the support column is also bonded to the nozzle plate portion.

[0028] Furthermore, in one embodiment of the present invention, the spacer portion is composed of a cured photosensitive thin-film resist fixed to the nozzle plate portion and the vibrating plate.

[0029] Furthermore, in one embodiment of the present invention, the nozzle plate portion includes a discharge path for the ink branching from the nozzle within the nozzle plate portion.

[0030] Furthermore, in order to solve the above-mentioned problems, the printing apparatus of the present invention is characterized by comprising: an inkjet head as described in any of the above claims; and a drive control unit for driving the inkjet head.

[0031] Furthermore, in order to solve the above-mentioned problems, the method for manufacturing a semiconductor device of the present invention is characterized in that a solvent-free ink is printed using the printing apparatus described above and a semiconductor is mounted on a substrate.

[0032] Furthermore, in order to solve the above-mentioned problems, the method for manufacturing an inkjet head of the present invention is characterized in that an adhesive photosensitive film resist is disposed on the nozzle plate portion or the vibrating plate, the photosensitive film resist is exposed and developed to form a pattern, the vibrating plate or the nozzle plate portion is disposed on the photosensitive film resist after the pattern is formed, and the laminate including the nozzle plate portion, the photosensitive film resist and the vibrating plate is post-baked to cure the photosensitive film resist and serve as the spacer portion, thereby forming a laminate in which the nozzle plate portion and the vibrating plate are bonded together with respect to the spacer portion.

[0033] Furthermore, in one aspect of the present invention, a temporary determining part is provided between the nozzle plate portion and the vibrating plate to define the gap between the nozzle plate portion and the vibrating plate, and the temporary determining part is removed after the actuator and the counterweight are disposed on the vibrating plate and the inkjet head is assembled.

[0034] Furthermore, in one aspect of the present invention, the height of the temporary determining portion is smaller than the height of the spacer portion.

[0035] The effects of the invention are as follows.

[0036] In this invention, an inkjet head is provided that can continuously eject droplets at a high frequency even when using inks with high viscosity. Attached Figure Description

[0037] Figure 1 This is a schematic cross-sectional view showing the structure of the inkjet head according to the first embodiment.

[0038] Figure 2 This is a schematic top view showing the shape of the base portion of the spring portion 31. Figure 2 (a) shows an example of a square. Figure 2 (b) shows an example of a circle.

[0039] Figure 3 This is a schematic cross-sectional view showing the ink flow path in the inkjet head of the first embodiment, showing the relationship with... Figure 1 The directions shown in the sectional view are orthogonal. Figure 3 (a) shows the state before the ink is ejected. Figure 3 (b) shows the state when the ink is ejected.

[0040] Figure 4This is an exploded perspective view showing the structure of the inkjet head according to the second embodiment.

[0041] Figure 5 This is a schematic top view showing the relationship between the vibrating plate 30 and the spacer portion 20 in the second embodiment.

[0042] Figure 6 This is a photograph illustrating an embodiment of the vibrating plate 30 in the second embodiment. Figure 6 (a) shows the state in which the thin plate portion 33 is stacked on the spring portion 31. Figure 6 (b) shows the state with the weight 34 fixed to the vibrating plate 30. Figure 6 (c) shows the area around the hammer 34 magnified.

[0043] Figure 7 This is a schematic top view showing a construction example of the actuator substrate 51 in the second embodiment.

[0044] Figure 8 This is a schematic perspective view showing the relationship between the actuator substrate 51 and the vibrating plate 30 in the second embodiment.

[0045] Figure 9 This is a diagram showing the simulation results of the inkjet head according to the third embodiment. Figure 9 (a) shows the ink flow rate distribution around the vibrating plate 30. Figure 9 (b) shows the pressure distribution of the ink around the vibrating plate 30.

[0046] Figure 10 This is a diagram showing the simulation results of changing the interval between the vibrating plate 30 and the nozzle plate portion 10 in the inkjet head of the third embodiment, showing the flow rate distribution of ink around the vibrating plate 30.

[0047] Figure 11 This is a graph showing the ink ejection results in the inkjet head according to the third embodiment. Figure 11 (a) shows the ink ejection speed. Figure 11 (b) shows the volume of ink ejected.

[0048] Figure 12 This is a schematic cross-sectional view showing the structure of the inkjet head according to the fourth embodiment.

[0049] Figure 13 This is a schematic cross-sectional view showing the structure of the inkjet head according to the fifth embodiment.

[0050] Figure 14 This is a schematic cross-sectional view showing the structure of the inkjet head according to the sixth embodiment.

[0051] Figure 15 This is a schematic cross-sectional view showing the structure of the inkjet head according to the seventh embodiment.

[0052] Figure 16 This is a schematic cross-sectional view showing the structure of the inkjet head according to the eighth embodiment.

[0053] Figure 17 This is a schematic cross-sectional view showing the structure of the inkjet head according to the ninth embodiment.

[0054] Figure 18 This is a schematic cross-sectional view showing the structure of the inkjet head according to the tenth embodiment.

[0055] Figure 19 This is a schematic top view of the plate that constitutes the beam in the tenth embodiment.

[0056] Figure 20 This is a schematic cross-sectional view showing the structure of the inkjet head according to the twelfth embodiment.

[0057] Figure 21 This is a schematic cross-sectional view showing the structure of the inkjet head according to the thirteenth embodiment. Detailed Implementation

[0058] (First Implementation)

[0059] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Identical or equivalent constituent elements, components, and processes shown in the drawings are labeled with the same symbols, and repeated descriptions are omitted where appropriate. Figure 1 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment.

[0060] like Figure 1 As shown, the inkjet head of this embodiment includes a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, a housing portion 40, and an actuator 50. A nozzle 11 is formed in the nozzle plate portion 10. The vibrating plate 30 includes a spring portion 31, a positioning portion 32, and a thin plate portion 33, with a counterweight 34 disposed on the positioning portion 32. An ink chamber 60 is formed on the side of the thin plate portion 33 closer to the nozzle plate portion 10 than the side of the thin plate portion 33 closer to the actuator 50 than the side of the thin plate portion 33 closer to the actuator 50 than the side of the thin plate portion 33 of the vibrating plate 30.

[0061] The nozzle plate 10 is a component that separates the ink chamber 60, which is filled with ink, from the destination from which the ink is ejected. A nozzle 11, which extends from the ink chamber 60 to the outside, is formed in the nozzle plate 10. Figure 1 The example shown depicts a nozzle plate 10 configured as a generally plate-like structure of uniform thickness, but different thicknesses, protrusions, recesses, etc., can also be formed as needed. Figure 1In this paper, a single plate-shaped component is shown as the nozzle plate portion 10, but the nozzle plate portion 10 can also be a stacked structure of a plate-shaped component on which the nozzle 11 is formed and a nozzle communication path substrate connected to the nozzle 11.

[0062] Nozzle 11 is a through hole formed in nozzle plate portion 10, through which ink filled in ink chamber 60 is ejected from ink chamber 60 to the outside. The shape of nozzle 11 is not limited, but... Figure 1 In the example shown, the nozzle 11 in the ink chamber 60 has a truncated cone shape with an enlarged diameter at the inlet side and a cylindrical shape with the same diameter at the outlet side. Specifically, the apex angle at the inlet side ranges from 20 degrees to 60 degrees, and the diameter at the outlet side ranges from 0.015 mm to 0.1 mm. By setting the nozzle 11 to a combination of a truncated cone and a cylinder, even high-viscosity inks can have their fluid resistance reduced when passing through the nozzle 11, enabling efficient droplet ejection.

[0063] The spacer portion 20 is a generally plate-shaped component with the opening described above, and is disposed between the nozzle plate portion 10 and the vibrating plate 30 to maintain the distance between the nozzle plate portion 10 and the vibrating plate 30. For example... Figure 1 As shown, the nozzle 11 is located inside the opening of the spacer portion 20, and the opening forms part of the ink chamber 60. Furthermore, the lower surface of the spacer portion 20 contacts the nozzle plate portion 10 and is fixed by an adhesive or the like, and the upper surface contacts the vibrating plate 30 and is fixed by an adhesive or the like.

[0064] The vibrating plate 30 is a component disposed on the spacer section 20 to separate the ink chamber 60 from the receiving chamber 70, and vibrates within the ink chamber 60 with the movement of the weight 34. Figure 1 In the example shown, the vibrating plate 30 includes a metal spring portion 31 that is a beam-shaped component, a positioning portion 32 formed in the spring portion 31, and a thin plate portion 33 made of a flexible sheet. The vibrating plate 30 separates the ink chamber 60 and the receiving chamber 70, so even when the ink chamber 60 is filled with ink, the ink will not reach the receiving chamber 70 side, thus preventing the weight 34 and actuator 50 disposed in the receiving chamber 70 from contacting the ink. This allows for the use of conductive ink materials and inks containing functional microparticles, increasing the freedom of ink material selection. Furthermore, since the movement of the weight 34 and actuator 50 is not hindered by the ink, even when using ink materials with high viscosity, the energy applied to the actuator 50 can be efficiently transferred to the weight 34 and the vibrating plate 30, resulting in efficient droplet ejection from the nozzle 11.

[0065] The spring section 31 is a beam-shaped elastic component integrally formed with a metal frame. It moves towards the ink chamber 60 in conjunction with the movement of the weight 34 launched by the actuator 50, and moves towards the storage chamber 70 based on elastic force. A positioning section 32 is formed in the spring section 31 at a position opposite to the nozzle 11, and the weight 34 is fitted and positioned in the positioning section 32. As will be explained below, the shape of the spring section 31 can be a wide, flat pedestal section with the weight 34 abutting against it, or a beam section extending from both sides of the pedestal section with supports at both ends. However, any structure that can elastically restore the position of the weight 34 is acceptable, and it can also be a cantilever beam structure or other structures.

[0066] Figure 2 This is a schematic top view showing the shape of the base portion of the spring portion 31. Figure 2 (a) shows an example of a square. Figure 2 (b) shows a circular example. The pedestal part is in Figure 2 The example shown in (a) has a square shape with a width of W and a length of W. Figure 2 The example shown in (b) has a circular shape with a diameter D. Figure 2 In the examples shown in (a) and (b), the widths of the pedestal portion are W and D, which are wider than the beam portion. Squares and circles are shown here, but rectangles and ellipses are also possible. As explained below, when multiple nozzles 11 and spring portions 31 are provided, a circle is preferred as the pedestal portion in order to suppress interference with adjacent nozzles 11 and improve ejection efficiency. Furthermore, when a rectangle is used as the pedestal portion, it is preferable to form rounded corners by increasing the thickness of the corner portions of the rectangle to prevent cracks in the thin plate portion 33 due to stress concentration at the corner portions.

[0067] The positioning part 32 is a hole formed in the spring part 31 at the position opposite to the nozzle 11. The diameter of the hole is smaller than the diameter of the counterweight 34. The counterweight 34 abuts against and fits into the hole to be positioned. Figure 1 In the middle, a through hole is shown as the positioning part 32, but the structure is not limited as long as it can position the weight 34. A concave part (a blind hole that does not pass through) or a convex part (e.g., a ridge-shaped convex part that protrudes in a circular shape in order to position the weight 34) can also be formed.

[0068] The thin plate portion 33 is a flexible, sheet-like component that is laminated and bonded to the spring portion 31 of the vibrating plate 30 and the frame. Furthermore, the thin plate portion 33 is bonded to the spring portion 31 of the vibrating plate 30 and the frame, sealing the space between them. The thin plate portion 33 is positioned between the ink chamber 60 and the receiving chamber 70, sealing them and thus separating the ink chamber 60 from the receiving chamber 70. Moreover, because the thin plate portion 33 is flexible, it deforms between the ink chamber 60 and the receiving chamber 70 in response to the movement of the counterweight 34 and the spring portion 31. Figure 1 In the example shown, an opening with a diameter approximately the same as that of the positioning part 32 is formed in the thin plate part 33 at a position corresponding to the positioning part 32. However, as long as the counterweight 34 can be fitted and positioned in the positioning part 32, the opening may not be formed.

[0069] The counterweight 34 is a generally spherical component disposed between the actuator 50 and the vibrating plate 30, and is positioned by abutting and engaging with the positioning part 32. When the inkjet head is not driven, the counterweight 34 abuts against the actuator 50, and is held in a position balanced with the restoring force of the spring part 31 by the front end of the actuator 50 towards the ink chamber 60. Figure 1 In the example shown, the weight 34 is fixed to the opening of the thin plate portion 33 and the positioning portion 32 using adhesive. However, if the weight 34 does not fall off the positioning portion due to the balance between the force applied by the actuator 50 and the restoring force of the spring portion 31, it may not be necessary to fix it with adhesive. Here, the weight 34 is shown as a sphere, but it is not limited to any object that flies by utilizing the momentum generated by the deformation of the actuator 50. For example, it could also be a rectangular block shape.

[0070] The housing portion 40 is a component that forms the shape of the inkjet head and holds the vibrating plate 30, the spacer portion 20, and the nozzle plate portion 10. Furthermore, a receiving chamber 70 is formed inside the housing portion 40, and the housing portion 40 positions and holds the actuator 50. Also, as explained below, an ink flow path is formed in the housing portion 40, through which ink is supplied from the outside to the ink chamber 60.

[0071] The actuator 50 is a component that is driven by an external drive signal, deforms by applying voltage, and transfers kinetic energy to the weight 34, which abuts against its front end, causing it to fly towards the nozzle 11. The actuator 50 can use currently known materials and constructions, such as piezoelectric materials using lead zirconate titanate (PZT: PbTiO3-PZrO3 solid solution). As described above, the front end of the actuator 50 abuts against the weight 34, and when the actuator 50 is not driven, force is applied to the weight 34 and the spring portion 31 in the direction of the ink chamber 60. Here, the amount of force applied and pressed towards the weight 34 and the spring portion 31 in the direction of the ink chamber 60 is not limited, and is set according to the elastic constant of the spring portion 31 and the mass of the weight 34. As an example, it is preferable to apply a few μm to a few tens of μm from the position where no external force is applied to the spring portion 31. The actuator 50 has electrodes for applying voltage (not shown), but since the receiving chamber 70 is separated from the ink chamber 60 by the vibrating plate 30, the ink does not come into contact with the actuator 50, so even if the ink is made of a conductive material, it does not hinder the operation of the actuator 50.

[0072] The ink chamber 60 is a space comprised of the nozzle plate portion 10, the spacer portion 20, and the vibrating plate 30. Ink is filled into the chamber through the ink flow path and ink supply orifice described below. Furthermore, the area including the inlet of the nozzle 11 constitutes the ejection area, and other areas within the ink chamber 60 adjacent to the ejection area are storage areas. Figure 1 In the example shown, the area with the width W of the spring portion 31 is the ejection region, and the surrounding area is the storage region. The distance (gap) between the nozzle plate portion 10 and the vibrating plate 30 in the storage region is the distance d1 between the nozzle plate portion 10 and the thin plate portion 33, and the distance (gap) between the nozzle plate portion 10 and the vibrating plate 30 in the ejection region is the distance d2 between the nozzle plate portion 10 and the spring portion 31. In this case, the distance d2 is smaller than the distance d1. The distances d1 and d2 are not limited, but regarding the distance d2, in order to efficiently eject inks with high viscosity, it is preferable to set it to a range of 1 μm or more and 50 μm or less, and more preferably to a range of 5 μm or more and 30 μm or less.

[0073] When the distance between two opposing plates at a distance d2 is reduced and the liquid filling the space between the plates is compressed, the pressure acting on the plates is proportional to the width W of one side if the plate is square, and proportional to the fourth power of the diameter D of the plate if the plate is circular, and inversely proportional to the cube of the distance d2. Similarly, the resistance of the ejection area is proportional to the square of the plate size and inversely proportional to the cube of the distance d2. Furthermore, the volume of ink flowing from the ejection area to the nozzle 11 and the storage area due to the displacement of the vibrating plate 30 is proportional to the square of the plate size. Making d1 larger than d2 is effective in increasing the ink supply from the storage area to the ejection area, thereby increasing the ejection frequency, and reducing the pressure in the storage area that inhibits the displacement of the vibrating plate, thereby increasing the ejection speed and thus improving ejection efficiency. Preferably, the distance d1 is set to be more than twice the distance d2.

[0074] Within the ink chamber 60, the distance d2 in the ejection region is made smaller than the distance d1 in the storage region. This suppresses the expansion of ink from the ejection region toward the storage region when pressure is applied to the ink within the ink chamber 60 by the movement of the counterweight 34 and the spring 31. This is because a smaller distance d2 increases the fluid resistance as the ink moves laterally within the ink chamber 60. Consequently, the movement of the counterweight 34 is efficiently transmitted to the ink as movement from the spring 31 toward the nozzle 11, increasing the droplet velocity even for inks with high viscosity, such as 20 mPa·s or higher. While there is no upper limit to the ink viscosity, it is preferably 1 Pa·s or less, and more preferably 200 mPa·s or less, for optimal droplet ejection. Furthermore, since the distance d1 in the storage region is larger than the distance d2 in the ejection region, ink can be rapidly supplied to the ink chamber 60 from the outside, preventing insufficient ink even during high-frequency droplet ejection.

[0075] If the width W of the ejection area within the ink chamber 60 is too large, it becomes difficult for ink to flow from the storage area into the vicinity of the nozzle 11 in the ejection area, making it difficult to eject droplets from the nozzle 11 at a high frequency. Furthermore, if the width W of the ejection area is too small, even if pressure is applied to the ink within the ejection area using the movement of the counterweight 34 and the spring 31, the lateral fluid resistance is insufficient, increasing the amount of ink moving towards the storage area, thus making it difficult to ensure the volume and velocity of the droplets ejected from the nozzle 11 to the outside. Preferably, the width W of the ejection area is in the range of 200 μm or more and 2 mm or less, and more preferably in the range of 200 μm or more and 1 mm or less.

[0076] The storage chamber 70 is a space formed inside the housing portion 40, which houses the counterweight 34 and the actuator 50. As described above, the storage chamber 70 is separated from the ink chamber 60 by the thin plate portion 33 of the vibrating plate 30. The storage chamber 70 is not filled with ink, and space is ensured around the actuator 50 and the counterweight 34.

[0077] Figure 3 This is a schematic cross-sectional view showing the ink flow path in the inkjet head of this embodiment, illustrating the relationship with... Figure 1 The directions shown in the sectional view are orthogonal. Figure 3 (a) shows the state before the ink is ejected. Figure 3 (b) shows the state of the ink as it is ejected. For example... Figure 3 As shown in (a) and (b), ink flow paths 41 and 42 are formed in the housing portion 40, and ink supply holes 35 and ink discharge holes 36 are formed in the vibrating plate 30 at positions corresponding to the ink flow paths 41 and 42. When ink is supplied to the ink flow path 41 from the outside of the housing portion 40, the ink reaches the ink chamber 60 via the ink flow path 41 and the ink supply hole 35. Since ink is continuously supplied to the ink flow path 41 from the outside, the ink filling the ink chamber 60 is discharged to the outside and recycled via the ink discharge hole 36 and the ink flow path 42. The recycled ink can also be reused by a recycling system and supplied to the ink flow path 41.

[0078] like Figure 3 As shown in (b), if the actuator 50 is driven by a drive signal and a voltage is applied, the actuator 50 deforms due to the piezoelectric effect, and the weight 34, which was in contact with the front end of the actuator 50, is thrown towards the nozzle 11. The weight 34, thrown by the actuator 50, causes the thin plate portion 33 and the spring portion 31 to elastically deform and be pressed into the ink chamber 60. At this time, in the ejection area including the inlet of the nozzle 11, pressure is applied to the ink in the outward direction (lower part of the figure) to generate flow, and droplets of ink are ejected after passing through the nozzle 11. The spring portion 31 returns to its original shape due to the elastic force, causing the weight 34 to abut against the front end of the actuator 50 again and return to its original position. Figure 3 The state of (a) is repeated during the period when the actuator 50 is driven according to the drive signal. Figure 3 The jetting action shown in (a) and (b) involves repeatedly ejecting droplets of ink from the nozzle 11 of the inkjet head.

[0079] As described above, in the inkjet head of this embodiment, the receiving chamber 70 and the ink chamber 60 are separated by the vibrating plate 30. This allows the actuator 50 and the counterweight 34 to be separated from the ink without filling the receiving chamber 70 with ink, thus enabling the use of various inks and increasing the freedom of ink material selection. Furthermore, it reduces the loss of kinetic energy transmitted from the actuator 50 to the vibrating plate 30 via the counterweight 34, enabling the continuous ejection of high-viscosity inks at a higher frequency.

[0080] Furthermore, the ink chamber 60 has an ejection area including the inlet of the nozzle 11 and a storage area adjacent to the ejection area. Regarding the gap between the nozzle plate portion 10 and the vibrating plate 30, the distance d2 in the ejection area is smaller than the distance d1 in the storage area. Therefore, even for inks with a high viscosity of 20 mPa·s or more, such as inks with a high viscosity of 20 mPa·s or more and 1 Pa·s or less, the speed of the ejected droplets can be increased.

[0081] (Second Implementation)

[0082] Next, the second embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 4 This is an exploded perspective view showing the structure of the inkjet head according to this embodiment. Figure 4 As shown, the inkjet head has a structure that combines a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, and a housing portion 40. Figure 4 In the middle, the thin plate portion 33 is bonded to the surface of the vibrating plate 30 opposite to the housing portion 40, which is not shown in the figure. In this embodiment, the difference from the first embodiment is that a plurality of nozzles 11 are provided in the nozzle plate portion 10, and correspondingly, a plurality of spring portions 31, a counterweight 34, an ink supply hole 35, an ink discharge hole 36, and an actuator 50 (not shown in the figure) are also provided.

[0083] A plurality of nozzles 11 are formed in a straight line at equal intervals on the nozzle plate 10. A spring portion 31 with two supporting beams is formed on the vibrating plate 30 at a position opposite to each nozzle 11. Furthermore, a counterweight 34 is arranged in combination with each spring portion 31. Figure 4 In this embodiment, the weights 34 are shown separated from the vibrating plate 30 on the housing portion 40 side. However, similar to the first embodiment, the weights 34 are respectively fitted and positioned and fixed to the positioning portions 32 of the spring portion 31. Furthermore, a plurality of ink supply holes 35 and ink discharge holes 36 are formed near the root of the beam-shaped portion in the vibrating plate 30 and the spring portion 31.

[0084] The spacer portion 20 has an opening 21 that includes multiple spring portions 31. Multiple slits 22 and tongue-shaped portions 23 are alternately formed on the upper and lower edges of the opening 21. The slits 22 are portions of the opening 21 that extend to multiple ink supply holes 35 and ink discharge holes 36. The tongue-shaped portions 23 are portions of the spacer portion 20 that extend to cover the root of the beam-shaped portion of the multiple spring portions 31.

[0085] The ink flow paths 41 and 42 of the housing 40 include cylindrical through holes for ink inflow and outflow paths to the outside, and enlarged portions formed to connect with the through holes in a manner that covers a plurality of ink supply holes 35 and ink discharge holes 36. Therefore, in the inkjet head of this embodiment, ink supplied from the through holes of the ink flow path 41 reaches the plurality of ink supply holes 35 via the enlarged portions, and fills the opening 21 constituting the ink chamber 60 from the ink supply holes 35 via the cut-out portion 22. The ink in the ink chamber 60 reaches the cut-out portion 22 on the opposite side via the opening 21, and is discharged from the ink discharge hole 36 via the enlarged portion of the ink flow path 42 and the through holes and is recovered.

[0086] Figure 5 This is a schematic top view showing the relationship between the vibrating plate 30 and the spacer portion 20 in this embodiment. The area depicted by the dashed line in the figure shows the shape of the opening 21 in the spacer portion 20. Figure 5 As shown, if the spacer portion 20 and the vibrating plate 30 are stacked, the ink supply hole 35 and the ink discharge hole 36 are located at the front end of the cut portion 22. Therefore, the ink that reaches the ink supply hole 35 from the ink flow path 41 is supplied to the storage area and the ejection area of ​​the ink chamber 60 through the cut portion 22. Furthermore, the ink filling the ink chamber 60 reaches the ink discharge hole 36 through the cut portion 22 and is discharged from the ink flow path 42.

[0087] Furthermore, the spring portion 31 includes a straight beam portion 31a and a wide, flat pedestal portion 31b, with a positioning portion 32 formed on the pedestal portion 31b. The beam portion 31a extends from both sides of the pedestal portion 31b in the vertical direction shown in the figure and is integrally formed with the frame. If the part where the beam portion 31a connects to the frame is taken as the root, the tongue-shaped portion 23 of the spacer portion 20 is formed protruding into the interior of the frame and overlaps with the root of the beam portion 31a. Since the vibrating plate 30 and the spacer portion 20 are fixed by adhesive, the tongue-shaped portion 23 is also bonded to the root of the beam portion 31a, thereby reinforcing the root of each spring portion 31. By utilizing the reinforcement of the tongue-shaped portion 23, even in the case of elastic deformation of adjacent spring portions 31, it is possible to prevent deformation from being transmitted to the root and causing unexpected deformation in the spring portion 31.

[0088] Figure 6 This is a photograph illustrating an embodiment of the vibrating plate 30 of this embodiment. Figure 6 (a) shows the state in which the thin plate portion 33 is stacked on the spring portion 31. Figure 6 (b) shows the state with the weight 34 fixed to the vibrating plate 30. Figure 6 (c) shows the area around the hammer 34 magnified.

[0089] exist Figure 6In the example shown in (a), the thin plate portion 33 is made of a transparent film, illustrating the localized reflection of light by the surface of the thin plate portion 33. The transparent film is preferably a polyimide film or a polyphenylene sulfide (PPS) film. Furthermore, the thin plate portion 33 is disposed on the beam portion 31a and the pedestal portion 31b constituting the spring portion 31, and an opening is formed in the thin plate portion 33 at the positioning portion 32 of the pedestal portion 31b. An adhesive is applied circumferentially to the opening in the thin plate portion 33 to fix the pedestal portion 31b and the thin plate portion 33 in place.

[0090] exist Figure 6 In the examples shown in (b) and (c), a case is illustrated where counterweights 34 are mounted on the pedestal portion 31b and fixed with adhesive. Figure 6 As shown in (b), the thin plate portion 33 is stacked in such a way that it not only covers the spring portion 31 but also covers the frame to which the beam portion 31a is connected, and the frame and the thin plate portion 33 are also fixed by adhesive.

[0091] Figure 7 This is a schematic top view showing an example of the structure of the actuator substrate 51 in this embodiment. Figure 7 As shown, the actuator substrate 51 is a plate-shaped component formed from piezoelectric material such as PZT into a generally rectangular shape, with multiple actuators 50 formed along one side in a comb-like pattern. Although in Figure 7 The diagram is omitted, but electrodes are formed on both sides of the actuator 50. Applying a voltage to these electrodes causes the actuator 50 to extend and retract along the length of the comb teeth. The spacing between the comb-shaped actuators 50 is... Figure 4 to Figure 6 The spring portions 31 shown are spaced equally and are configured such that the front ends of the actuators 50 abut against the counterweights 34. The plurality of actuators 50 correspond to the actuators in this invention. The size and shape of the actuator substrate 51 are not limited; as an example, a substrate with actuators 50 of 5mm length formed at 0.5mm intervals on a 0.3mm thick PZT substrate can be provided.

[0092] Figure 8 This is a schematic perspective view showing the relationship between the actuator substrate 51 and the vibrating plate 30 in this embodiment. Figure 8 For simplicity, the nozzle plate portion 10, spacer portion 20, thin plate portion 33, and housing portion 40 are omitted from the illustration, but as shown in the figure... Figure 4 As shown, they are respectively configured and adhered to the back surface of the vibrating plate 30. For example... Figure 8 As shown, weights 34 are bonded and fixed to the spring portion 31 of the vibrating plate 30, and the front ends of the plurality of actuators 50 formed on the actuator substrate 51 are arranged to abut against the weights 34 respectively.

[0093] Force is applied to the actuator substrate 51 so that the front end of the actuator 50 abuts against the counterweight 34, pressing the counterweight 34 towards the spring portion 31. After determining the amount of pressing the counterweight 34 and the relative angle with respect to the vibrating plate 30, the actuator substrate 51 is fixed to the housing portion 40 with adhesive. Furthermore, a flexible cable 80 is mounted on one side of the actuator substrate 51, and each wire of the flexible cable 80 is connected to the individual electrodes of the actuator 50 and the common electrode shared by multiple actuators 50 using an anisotropic conductive film.

[0094] If a drive signal is transmitted from outside the inkjet head via the flexible cable 80, voltage is applied to the actuators 50 from both sides via the wiring, anisotropic conductive film, and electrodes of the flexible cable 80, thereby causing each actuator 50 to extend or retract independently. As the actuator 50 extends, kinetic energy is transferred to the counterweight 34, which abuts against the front end of the actuator 50, propelling the counterweight 34 towards the spring portion 31 and ejecting ink from the ink chamber 60 through the nozzle 11. Therefore, in the inkjet head of this embodiment, ink droplets can be ejected individually from multiple nozzles 11, enabling the desired ink coating operation.

[0095] And, as Figure 8 As shown, the front ends of both sides of the actuator substrate 51 where the actuator 50 is formed are bonded to the frame of the vibrating plate 30. The vibrating plate 30, the spacer portion 20, and the nozzle plate portion 10 are held by both sides of the actuator substrate 51. Here, the two sides of the actuator substrate 51 support the nozzle plate portion 10, which corresponds to the support member in this invention. The two sides of the actuator substrate 51 are integrally formed of the same piezoelectric material as the actuator 50, but since no electrodes are formed, they are non-driven portions that do not perform piezoelectric-based extension and retraction. By using the two sides of the actuator substrate 51, i.e., the non-driven portions, to hold the frame of the vibrating plate 30, the vibrating plate 30 can be held in a region as close as possible to the actuator 50 and the spring portion 31. As a result, the deformation of the frame caused by the extension and retraction of the actuator 50 can be suppressed, and the amount of variation of each actuator 50 and the spring portion 31 can be accurately controlled, thereby enabling accurate control of the ejection of ink droplets.

[0096] As described above, in the inkjet head of this embodiment, multiple actuators 50 can individually impart kinetic energy to multiple counterweights 34 and spring portions 31, thereby ejecting ink droplets from multiple nozzles 11. Furthermore, the frame of the vibrating plate 30 is held in place by the non-driving portion of the actuator substrate 51, which can suppress deformation of the frame and accurately control the ejection of ink droplets.

[0097] (Third Implementation)

[0098] Next, the third embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 9This is a diagram showing the simulation results of the inkjet head according to this embodiment. Figure 9 (a) shows the ink flow rate distribution around the vibrating plate 30. Figure 9 (b) shows the pressure distribution of the ink around the vibrating plate 30. Figure 9 In (a) and (b), the Z-axis direction is from the vibrating plate 30 toward the nozzle plate 10, and is in Figure 1 The direction of the ejected droplets (downward).

[0099] Figure 9 The simulation results shown in (a) and (b) illustrate the results of laminar flow stabilization calculations performed by dividing the spring section 31 into quarters from a top view. As simulation conditions, the width of the beam section 31a was set to 0.15 mm, the width of the pedestal section 31b to 0.5 mm, the length to 0.5 mm, and the diameter of the nozzle 11 to 40 μm. Furthermore, the distance d2 between the nozzle plate section 10 and the spring section 31 in the ejection area was set to 20 μm, the ink viscosity to 100 mPa·s, and the ink density to 1000 kg / m³. 3 The pedestal portion 31b moves toward the nozzle plate portion 10 at a speed of 0.1 m / s. Furthermore, the thickness of the spring portion 31 is set to 75 μm, and the distance d1 between the nozzle plate portion 10 and the thin plate portion 33 in the storage area is set to 95 μm.

[0100] Figure 9 In (a), tiny arrows indicate the direction of ink movement within ink chamber 60, and the shades of color indicate the ink flow rate. For example... Figure 9 As shown in (a), in nozzle 11, ink flows upward (outward from nozzle 11) at a relatively high flow rate. Furthermore, a region with a lower flow rate exists in a ring around nozzle 11, and ink flows out from the ejection area toward the storage area near the outer periphery of the platform portion 31b. Figure 9 In the pressure distribution shown in (b), with nozzle 11 as the center, the pressure is higher near the center of the base portion 31b and lower near the outer periphery of the base portion 31b.

[0101] Figure 10 This is a diagram showing the simulation results of changing the interval between the vibrating plate 30 and the nozzle plate portion 10 in the inkjet head of this embodiment, showing the flow rate distribution of ink around the vibrating plate 30. Figure 10 Images (a) to (f) show the velocity distribution when the distance d2 between the nozzle plate portion 10 and the spring portion 31 in the ejection region is set to 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, and 30 μm, respectively. Other conditions are the same as... Figure 9 The conditions shown are the same.

[0102] likeFigure 10 As shown in (a) to (f), as the distance d2 increases, the flow velocity of the ink moving from nozzle 11 toward the outside (upper part of the figure) decreases. Furthermore, the flow velocity in the in-plane direction around nozzle 11 and near the outer periphery of the platform portion 31b also decreases. Specifically, because the distance d2 increases, the amount of ink moving in the in-plane direction increases. Figure 10 The simulation results shown in (a) to (f) show that if the distance d2 in the ejection area is too large, it is impossible to impart sufficient velocity to the ink ejected from the nozzle 11 to the outside, thus making it difficult to eject droplets stably.

[0103] Next, an inkjet head was fabricated, and droplet ejection tests were conducted using inks of different viscosities. The inkjet head structure was the same as that shown in the second embodiment, using a beam structure with two end supports (beam 31a and base 31b) as the spring part 31 of the vibrating plate 30. The thickness of the vibrating plate 30 was 75 μm, the thickness of the spacer part 20 was 20 μm, the thickness of the nozzle plate part 10 was 100 μm, the diameter of the nozzle 11 was 40 μm, and the counterweights 34 used were counterweights with diameters of 0.6 mm and 0.8 mm. The frequency of the drive signal applied to the actuator 50 was 100 Hz, and the voltage was 240 V. As ink samples, standard viscometer calibration solutions JS50, JS100, and JS200 (manufactured by Nippon Lubricating Grease Co., Ltd.) were used. The viscosities of each ink sample JS50, JS100, and JS200 at approximately 25°C during the evaluation were 35 mPa·s, 73 mPa·s, and 136 mPa·s, respectively.

[0104] Figure 11 This is a graph showing the ink ejection results from the inkjet head of this embodiment. Figure 11 (a) shows the ink ejection speed. Figure 11 (b) shows the ink ejection volume. As the counterweight 34, a counterweight with a diameter of 0.6 mm is used in JS50 and JS100, and a counterweight with a diameter of 0.8 mm is used in JS200. Figure 11 The horizontal axis of (a) and (b) shows the distance (gap) d2 between the nozzle plate portion 10 and the base portion 31b in the ejection area. Figure 11 The vertical axis of (a) shows the velocity of the droplets ejected from nozzle 11. Figure 11 The vertical axis of (b) shows the ejection volume of each droplet ejected from nozzle 11.

[0105] like Figure 11As shown in (a), it can be confirmed that in any sample ink, an ejection velocity greater than 0 m / s is achieved, allowing droplets to be ejected from nozzle 11 even when using inks with very high viscosity. In particular, if droplets can be ejected from nozzle 11 at a velocity of 5 m / s or higher, the ejection direction of the droplets can be stabilized, improving the positional accuracy of ink coating. It can be confirmed that in sample inks JS50 and JS100, droplets can be ejected from nozzle 11 up to a distance of 30 μm from d2; however, to achieve ejection speeds of 5 m / s or higher, it is preferable to set the distance d2 to 20 μm or less. Furthermore, as... Figure 11 As shown in (b), it can be confirmed that the ejection volume of the ink is not significantly related to the distance d2. Regardless of the distance d2, droplets of approximately the same volume can be ejected.

[0106] In the inkjet head of this embodiment, when the spring portion 31 of the vibrating plate 30 moves toward the nozzle 11, the ink between the nozzle plate portion 10 and the vibrating plate 30 is compressed, and ink in the ejection area is ejected from the nozzle 11. Simultaneously, within the ejection area, the ink also moves outwards toward the storage area. The narrower the distance d2 between the nozzle plate portion 10 and the spring portion 31 in the ejection area, the greater the in-plane fluid resistance between the spring portion 31 and the nozzle plate portion 10, and more ink moves toward the nozzle 11. This is because the ink in the ejection area generates greater pressure, thus releasing the pressure and allowing the ink to pass through the nozzle 11.

[0107] As described above, in this embodiment, based on simulations and experiments, it was confirmed that by setting the distance d2 in the ejection region to a range of 1 μm or more and 50 μm or less, and setting the width W or diameter D of the platform portion 31b of the ejection region to a range of 200 μm or more and 2 mm or less, droplets can be ejected from the nozzle 11 even if the viscosity of the ink is 20 mPa·s or more and 1 Pa·s or less. To eject inks with higher viscosity, it is necessary to increase d2 and W or D, and to increase the mass of the counterweight 34. To impart sufficient kinetic energy to the counterweight 34, it is preferable that the mass of the actuator 50 is greater than the mass of the counterweight 34. More preferably, the mass of the actuator 50 is three times or more the mass of the counterweight 34.

[0108] (Fourth Implementation)

[0109] Next, the fourth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 12 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment.

[0110] like Figure 12As shown, the inkjet head of this embodiment includes a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, a housing portion 40, an actuator 50, an ink chamber 60, and a receiving chamber 70. A nozzle 11 is formed in the nozzle plate portion 10. The vibrating plate 30 includes a spring portion 31, a positioning portion 32, and a thin plate portion 33, with a counterweight 34 disposed on the positioning portion 32. The thin plate portion 33 is disposed on the ink chamber 60 side relative to the spring portion 31, and bulges out towards the receiving chamber 70 from the storage area of ​​the ink chamber 60. Within the ink chamber 60, the distance d1 between the thin plate portion 33 at its maximum bulge position and the nozzle plate portion 10 is greater than the distance d2 between the spring portion 31 and the nozzle plate portion 10 in the ejection area.

[0111] Even in the inkjet head of this embodiment, the receiving chamber 70 and the ink chamber 60 are separated by the thin plate portion 33 of the vibrating plate 30. This allows the actuator 50 and the counterweight 34 to be separated from the ink without filling the receiving chamber 70 with ink, thus enabling the use of various inks and increasing the freedom of ink material selection. Furthermore, it reduces the loss of kinetic energy transmitted from the actuator 50 to the vibrating plate 30 via the counterweight 34, enabling the continuous ejection of high-viscosity inks at a higher frequency.

[0112] Furthermore, the ink chamber 60 has an ejection area including the inlet of the nozzle 11 and a storage area adjacent to the ejection area. Regarding the gap between the nozzle plate portion 10 and the vibrating plate 30, the distance d2 in the ejection area is smaller than the distance d1 in the storage area, so that even for inks with high viscosity of 20 mPa·s or more and 1 Pa·s or less, the speed of the ejected droplets can be increased.

[0113] (Fifth Implementation)

[0114] Next, the fifth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 13 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment.

[0115] like Figure 13 As shown, the inkjet head of this embodiment includes a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, a housing portion 40, an actuator 50, an ink chamber 60, and a storage chamber 70. A nozzle 11 is formed in the nozzle plate portion 10, and a protrusion 12 protruding further into the ink chamber 60 than other areas is formed around the nozzle 11. The vibrating plate 30 includes a spring portion 31, a positioning portion 32, and a thin plate portion 33, and a counterweight 34 is disposed on the positioning portion 32. Within the ink chamber 60, the distance d1 between the thin plate portion 33 in the storage area and the nozzle plate portion 10 is greater than the distance d2 between the spring portion 31 and the protrusion 12 in the ejection area.

[0116] Figure 13The example shown is of a protrusion 12 protruding with the same width W as the spring portion 31, but the protrusion 12 may also be formed with a different width than the spring portion 31. Furthermore, the protrusion 12 is shown to have a shape with a flat upper surface, but it may also be formed from a curved surface, an inclined surface, a multi-layered surface, etc.

[0117] Even in the inkjet head of this embodiment, the receiving chamber 70 and the ink chamber 60 are separated by the thin plate portion 33 of the vibrating plate 30. This allows the actuator 50 and the counterweight 34 to be separated from the ink without filling the receiving chamber 70 with ink, thus enabling the use of various inks and increasing the freedom of ink material selection. Furthermore, it reduces the loss of kinetic energy transmitted from the actuator 50 to the vibrating plate 30 via the counterweight 34, enabling the continuous ejection of high-viscosity inks at a higher frequency.

[0118] Furthermore, the ink chamber 60 has an ejection area including the inlet of the nozzle 11 and a storage area adjacent to the ejection area. Regarding the gap between the nozzle plate portion 10 and the vibrating plate 30, the distance d2 in the ejection area is smaller than the distance d1 in the storage area, so that even for inks with high viscosity of 20 mPa·s or more and 1 Pa·s or less, the speed of the ejected droplets can be increased.

[0119] (Sixth Implementation Method)

[0120] Next, the sixth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 14 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment. This embodiment is a variation of the second embodiment.

[0121] like Figure 14 As shown, the inkjet head of this embodiment includes a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, a housing portion 40, actuators 50a and 50b, an ink chamber 60, and a receiving chamber 70. A plurality of nozzles 11 are formed in the nozzle plate portion 10, and a spring portion 31, a thin plate portion 33, and a counterweight 34 are arranged at positions corresponding to each nozzle 11. Furthermore, a spacer portion 20, a vibrating plate 30, and an adjustment portion 37 are arranged between adjacent nozzles 11, and an ink chamber 60 is formed for each nozzle 11.

[0122] In the area where the spacer portion 20 is formed, the adjustment portion 37 is disposed on the receiving chamber 70 side relative to the vibrating plate 30. The adjustment portion 37 is a component for adjusting the height of the surface in contact with the actuator 50b. The contact surface between the adjustment portion 37 and the vibrating plate 30 is fixed with adhesive. Figure 14As shown, the height of the upper surface of the adjusting part 37 is the same as the height of the position where the counterweight 34 and the actuator 50a abut. To ensure reliable contact between the adjusting part 37 and the front end of the actuator 50b regardless of manufacturing errors, it is preferable to position the upper surface of the adjusting part 37 slightly higher than the front end of the actuator 50a. Furthermore, the front end of the actuator 50b is contacted and fixed to the upper surface of the adjusting part 37 using an adhesive.

[0123] Actuators 50a and 50b are provided on the comb-shaped portion of actuator 50, which is made of piezoelectric material, and actuators 50a and 50b are arranged alternately. For example... Figure 14 As shown, the front end of actuator 50a abuts against the counterweight 34, and the front end of actuator 50b contacts the upper surface of adjustment part 37 and is fixed with adhesive. Actuator 50a is extended and retracted when a voltage is applied according to a drive signal to transmit kinetic energy to the counterweight 34, and therefore corresponds to the actuator in this application. Actuator 50b is not driven when no drive signal is applied and becomes a non-driven part, holding the vibrating plate 30, the spacer part 20, and the nozzle plate part 10 via adjustment part 37, and therefore corresponds to the support member in this invention.

[0124] exist Figure 14 In the inkjet head shown, a stacked structure of spacer portion 20, vibrating plate 30, and adjustment portion 37 is formed between multiple actuators 50a, and this stacked structure is maintained by the non-driving portion of the actuator 50, namely the actuator 50b. As a result, the deformation of the spring portion 31 in adjacent ink chambers 60 due to the extension and retraction of the actuator 50a can be suppressed, and the control accuracy of droplet ejection in each ink chamber 60 can be improved.

[0125] Figure 14 The example shown depicts the adjustment section 37 and the vibrating plate 30 as separate components. However, the vibrating plate 30 and the adjustment section 37 can also be integrally formed by increasing the thickness of the vibrating plate 30 in the region opposite to the actuator 50b. Alternatively, the thin plate section 33 can be extended to the region of the actuator 50b, and the thickness of the thin plate section 33 in the region opposite to the actuator 50b can be increased to integrally form the thin plate section 33 and the adjustment section 37.

[0126] As described above, in the inkjet head of this embodiment, a stacked structure including spacer portions 20 is provided between adjacent plurality of actuators 50a. Since the stacked structure including spacer portions 20 is maintained by the non-driving portion of the actuator 50, i.e., the actuator 50b, the control accuracy of droplet ejection in each ink chamber 60 can be improved.

[0127] (Seventh Implementation)

[0128] Next, the seventh embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 15This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment.

[0129] Figure 15 The structure shown in (a) is a variation of the first embodiment. In the first embodiment, a flexible sheet-like component is used as the thin plate portion 33, but a sheet-like component made of metal capable of elastic deformation can also be used as the thin plate portion 33. Furthermore, in the first embodiment, the spring portion 31 and the thin plate portion 33 are separately constructed, but they can also be integrally formed from the same material.

[0130] Figure 15 The structure shown in (b) is a variation of the first embodiment. In the first embodiment, a positioning portion 32 with a through hole is formed in the spring portion 31, but a concave positioning portion 32a may also be formed on the receiving chamber 70 side of the spring portion 31. The positioning portion 32a is concave and does not extend from the receiving chamber 70 to the ink chamber 60, so it is not necessary to use an adhesive to seal the opening of the thin plate portion 33 to prevent ink leakage.

[0131] Figure 15 The construction shown in (c) is Figure 15 A variation of (b). In this variation, a concave positioning portion 32a is formed in the spring portion 31, and the thin plate portion 33 is positioned on the ink chamber 60 side relative to the spring portion 31, so that it is not necessary to form an opening in the thin plate portion 33 at the position corresponding to the positioning portion 32a, and the isolation between the ink chamber 60 and the storage chamber 70 becomes easier.

[0132] Figure 15 The construction shown in (d) is Figure 15 A variation of (c). In the second embodiment, the spring portion 31 is constructed using a beam portion 31a extending from both sides of the pedestal portion 31b as a two-end support beam structure, but it may also be constructed with a helical spring 38 holding the pedestal portion 31b of the spring portion 31.

[0133] This invention is not limited to the embodiments described above, and various modifications can be made within the scope of the claims. The technical scope of this invention also includes embodiments obtained by appropriately combining the technical solutions disclosed in different embodiments. The actuator can utilize a laminated piezoelectric element. By using a laminated piezoelectric element, the driving voltage can be reduced.

[0134] (Eighth Implementation Method)

[0135] Next, the eighth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 16 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment.

[0136] Figure 16The structure shown is a variation of the first embodiment. In the first embodiment, the vibrating plate 30 includes a spring portion 31, a hole formed in the spring portion 31 (i.e., a positioning portion 32), and a thin plate portion 33, with a counterweight 34 disposed on the positioning portion 32. In contrast, in this embodiment, the thin plate portion 33 has a pedestal portion 33a on its main surface on the side of the storage chamber 70, and the counterweight 34 is positioned on the pedestal portion 33a.

[0137] Since the counterweight 34 is positioned on the base portion 33a, the spring portion 31 may not have a hole. Figure 16 The cross-section shown can also be rectangular. The thin plate portion 33 may also lack an opening. Figure 16 The cross-section shown can also be rectangular.

[0138] When the spring portion 31 has a hole in the positioning portion 32, the thin plate portion 33 with an opening needs to be precisely bonded to the spring portion 31 with the hole. However, since the counterweight 34 needs to be bonded to the circumference of the hole in the positioning portion 32 and the circumference of the opening in the thin plate portion 33, if a gap is formed between the positioning portion 32 and the thin plate portion 33 and the counterweight 34, there is a concern that ink may leak into the collection chamber 70. Furthermore, it is sufficient to fill the gap in the positioning portion 32 opposite to the nozzle with adhesive, but if the adhesive is not filled sufficiently, air bubbles will accumulate in the gap in the positioning portion 32, affecting the ejection characteristics. As described in this embodiment, the thin plate portion 33 has a base portion 33a on the main surface on the collection chamber 70 side. When the counterweight 34 is positioned in the base portion 33a, the hole in the spring portion 31 is not required, and a flat vibrating plate can be used. A flat vibrating plate can obtain good ejection characteristics.

[0139] To ensure ink ejection accuracy, the position where the counterweight 34 is positioned on the vibrating plate 30 needs to be opposite to the nozzle 11 via the vibrating plate 30. By providing the pedestal portion 33a on the thin plate portion 33 in such a way that the counterweight 34 is positioned opposite to the nozzle 11, the counterweight 34 can be positioned on the vibrating plate 30 with high precision.

[0140] The material of the pedestal portion 33a can be an adhesive photosensitive film resist. The adhesive photosensitive film resist is preferably applied to the sheet portion 33 by pressing or hot pressing.

[0141] By exposing and developing the photosensitive film resist disposed on the thin plate portion 33, a pattern can be formed to create a base portion 33a of a desired shape. The photosensitive film resist with adhesive properties is not particularly limited; for example, a film-shaped photosensitive adhesive material manufactured by Tokyo Ohka Kogyo Co., Ltd. can be used. This photosensitive adhesive material has a film shape of a predetermined thickness and adhesive properties, thus it can be adhered to the thin plate portion 33 with good thickness accuracy. Furthermore, post-baking after adhesion allows the base portion 33a to be easily bonded to the thin plate portion 33.

[0142] (Ninth Implementation)

[0143] Next, the ninth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 17 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment. This embodiment is a variation of the eighth embodiment.

[0144] The spring portion 31 has a protrusion 31c on its main surface facing the nozzle 11, which is opposite to the inlet of the nozzle 11. The protrusion 31c is configured to be inserted into the inlet of the nozzle 11 with a gap. The protrusion 31c can be inserted into the inlet of the nozzle 11 with a gap when the actuator 50 is driven, or it can be inserted into the inlet of the nozzle 11 with a gap before and during the actuator 50 is driven, but it is preferable to insert into the inlet of the nozzle 11 with a gap before and during the actuator 50 is driven.

[0145] The spring portion 31 has a protrusion 31c, which prevents air from accumulating at the inlet side of the nozzle 11 within the nozzle plate portion 10. Furthermore, the smaller the distance d2 between the nozzle plate portion 10 and the spring portion 31, the easier it is to feed ink into the nozzle 11, thereby suppressing ink leakage into the storage area. Additionally, the ink flow resistance can be precisely controlled using the gap (the gap between the double cylinders) between the sidewall of the protrusion 31c and the sidewall of the nozzle 11 inlet. The gap (the gap between the double cylinders) between the sidewall of the protrusion 31c and the sidewall of the nozzle 11 inlet is preferably 5 μm to 20 μm before, and during, the actuator operation. By setting the gap within the aforementioned preferred range, foreign matter can be prevented from being trapped in the gap, and the ink flow resistance can be precisely controlled.

[0146] (Tenth Implementation)

[0147] Next, the tenth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 18 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment. This embodiment is a variation of the second embodiment.

[0148] like Figure 18As shown, the inkjet head of this embodiment includes a nozzle plate portion 10, a spacer portion 20, a vibrating plate 30, a beam 14, a housing portion 40, an actuator 50, an ink chamber, and a storage chamber. A plurality of nozzles 11 are formed in the nozzle plate portion 10, and a spring portion 31, a thin plate portion 33, and a counterweight 34 are arranged at positions corresponding to each nozzle 11.

[0149] The vibrating plate 30 has a beam 14 on the main surface of the receiving chamber side of the thin plate section 33, and a support column 13 on the main surface of the ink chamber 60 side of the thin plate section 33. The beam 14 and the support column 13 are positioned opposite each other across the thin plate section 33 between adjacent multiple counterweights 34 and are bonded to the thin plate section 33. The support column 13 is also bonded to the nozzle plate section 10.

[0150] If multiple actuators are driven simultaneously, a large pressure is generated between the vibrating plate 30 and the nozzle plate 10, causing the nozzle plate 10 to flex and the nozzle 11 to retract in the ejection direction. This results in a portion of the energy used by the actuator 50 to press the vibrating plate 30 via the counterweight 34 being lost. In contrast, the vibrating plate 30 has a support column 13 that is also bonded to the nozzle plate 10, and a beam 14 is provided opposite to the support column 13 across the thin plate 33, thereby improving the rigidity of the nozzle plate 10.

[0151] The support column 13 may also have the following layered structure: the side bonded to the vibrating plate 30 is made of the same component as the vibrating plate 30, and the side bonded to the nozzle plate portion 10 is made of the same component as the spacer portion 20. The support column 13 may be formed of the same material as the vibrating plate 30 and the spacer portion 20, or it may be formed of a different material.

[0152] Beam 14 can be constructed by Figure 19 The beam 14 shown is formed by stacking and bonding plates to the thin plate portion 33. The height of the beam 14 can be adjusted according to the thickness of the plates constituting the beam 14. The greater the height of the beam 14, the greater the effect of improving the rigidity of the nozzle plate portion 10. Therefore, it is preferable that the height of the beam 14 can be, for example, 300 μm or more, or the height of the counterweight 34 or more.

[0153] (Eleventh Implementation Method)

[0154] Next, the eleventh embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. In this embodiment, the spacer portion 20 is composed of a cured photosensitive thin-film resist fixed to the nozzle plate portion 10 and the vibrating plate 30.

[0155] Since the gap between the nozzle plate portion 10 and the vibrating plate 30 affects the ejection characteristics, including the ink ejection speed, ejection volume, and ejection direction, it needs to be constructed with high precision. However, since the gap is relatively narrow, when the spacer portion 20 is fixed to the nozzle plate portion 10 and the vibrating plate 30 using an adhesive, the gap will change due to the thickness of the adhesive.

[0156] By using an adhesive photosensitive thin-film resist as the material for the spacer portion 20, the nozzle plate portion 10 and the vibrating plate 30 can be fixed to the spacer portion 20 even without the use of an adhesive. Since no adhesive is present between the nozzle plate portion 10 and the vibrating plate 30 and the spacer portion 20, the spacing between the nozzle plate portion 10 and the vibrating plate 30 can be formed with high precision. Furthermore, since the resist is a thin-film dry resist, it can be uniformly and easily applied to the nozzle plate portion or the vibrating plate containing the nozzle.

[0157] The formation of a laminated structure of a nozzle plate portion 10, a spacer portion 20, and a vibrating plate 30 using an adhesive photosensitive thin film resist can be performed by the following method: an adhesive photosensitive thin film resist is disposed on the nozzle plate portion or the vibrating plate; the photosensitive thin film resist is exposed and developed to form a pattern; the vibrating plate or the nozzle plate portion is disposed on the patterned photosensitive thin film resist; the laminate containing the nozzle plate portion, the photosensitive thin film resist, and the vibrating plate is post-baked to cure the photosensitive thin film resist and serve as the spacer portion, thereby forming a laminate in which the nozzle plate portion and the vibrating plate are bonded together with respect to the spacer portion.

[0158] The application of the adhesive photosensitive film resist to the nozzle plate or vibrating plate is preferably performed by pressing or hot pressing. Similarly, the placement of the vibrating plate or nozzle plate onto the photosensitive film resist after patterning is also preferably performed by pressing or hot pressing.

[0159] The above-described pattern formation involves exposing and developing an adhesive photosensitive thin-film resist to create openings. The adhesive photosensitive thin-film resist is not particularly limited; for example, a thin-film-shaped photosensitive adhesive material (photosensitive permanent film TMMF NS-1020) manufactured by Tokyo Ohka Kogyo Co., Ltd. can be used. Because this photosensitive adhesive material is a thin-film shape with a predetermined thickness and possesses adhesive properties, it can be bonded with good thickness accuracy between the nozzle plate and the diaphragm. Furthermore, post-bakement after bonding facilitates the easy combination of the nozzle plate, the diaphragm, and the spacers between them.

[0160] (Twelfth Implementation)

[0161] Next, the twelfth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 20 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment. This embodiment is the one shown in the first embodiment. Figure 3 A variation of the above.

[0162] Figure 20 This is a schematic cross-sectional view showing the ink flow path in the inkjet head of this embodiment and the air discharge path branching off from the nozzle, showing the state before ink is ejected. Figure 20 As shown, ink flow paths 41 and 42 are formed in the housing portion 40. An ink supply hole 35 and an ink discharge hole 36 are formed in the vibrating plate 30 at positions corresponding to the ink flow paths 41 and 42. An air discharge flow path 44, branching from the nozzle 11, is formed in the housing portion 40 and the nozzle plate portion 10. The air discharge flow path may consist of only one side of the nozzle 11, or it may consist of air discharge flow paths 43 and 44 on both sides of the nozzle 11. With this air discharge flow path, it is difficult to draw air in from the nozzle 11 side, and even if air is drawn in, it can be quickly discharged. Furthermore, based on the viewpoint of aligning the ink ejection direction as closely as possible with the nozzle axis, it is preferable to have air discharge flow paths 43 and 44 on both sides of the nozzle 11. The air discharge flow paths 43 and 44 suppress pressure deviation within the nozzle 11 during ejection. Furthermore, by causing the ink to flow slowly from one side of the air discharge channels 43 and 44 to the other, air discharge can be promoted and changes in the physical properties of the ink at the nozzle can be suppressed.

[0163] If the inlet side of nozzle 11 has a relatively large space, air can easily get trapped in that space, affecting the ink ejection characteristics. In particular, if the thickness of nozzle plate 10 is greater than the distance d2 in order to improve the rigidity of nozzle plate 10, then the distance d2 is narrower. Consequently, a larger space is formed on the inlet side of the nozzle within the nozzle plate, and air can easily get trapped in that space. By providing an air discharge path 44, air can be discharged, thus suppressing air from getting trapped in the space on the inlet side of nozzle 11.

[0164] While it is possible to draw air from the nozzle outlet, this requires stopping printing and installing a suction cap on the nozzle 11, which is cumbersome. The inkjet head has an air exhaust path 44, so printing does not need to be stopped and a suction cap on the nozzle 11 is not required.

[0165] The air discharge path 44 can discharge ink along with air and can recover the discharged ink. The recovered ink is degassed by a degassing device assembled in the circulation system and reused, and is supplied to the ink path 41 and / or the air discharge path 43.

[0166] When the air exhaust flow path 44 is provided, the flow path is relatively narrowed such that the fluid resistance of the air exhaust flow path 44 is higher than the fluid resistance of the nozzle 11, so as not to substantially affect the ejection characteristics of the ink ejected from the nozzle 11. The fluid resistance of the air exhaust flow path 44 is preferably 5 to 30 times the fluid resistance of the nozzle 11, more preferably 7 to 20 times, and even more preferably 9 to 15 times. The preferred fluid resistance of the air exhaust flow path 43 is also the same.

[0167] (Thirteenth Implementation Method)

[0168] Next, the thirteenth embodiment of the present invention will be described. Descriptions that are repeated in the first embodiment will be omitted. Figure 21 This is a schematic cross-sectional view showing the structure of the inkjet head according to this embodiment. This embodiment is a variation of the eleventh embodiment.

[0169] In the formation of the nozzle plate portion 10, spacer portion 20, and diaphragm 30 using an adhesive photosensitive thin-film resist in the eleventh embodiment, a temporary determining portion 39 for specifying the distance d2 between the nozzle plate portion 10 and the diaphragm 30 may be provided between them. After the actuator 50 and the counterweight 34 are arranged on the diaphragm 30 and the inkjet head is assembled, the temporary determining portion 39 is removed. After the inkjet head is assembled, it means that in the state where the inkjet head is not driven, the counterweight 34 abuts against the actuator 50 and is forced towards the ink chamber 60 by the front end of the actuator 50, thereby maintaining a position balanced with the restoring force of the spring portion 31.

[0170] The distance d2 has a significant impact on the ink ejection characteristics, requiring high precision to minimize the deviation of the distance d2 corresponding to each nozzle. When the vibrating plate 30 is stacked after the temporary determining part 39 is formed, the influence of the deflection of the vibrating plate 30 and the deformation of the vibrating plate 30 itself on the distance d2 can be reduced. Therefore, after the housing part 40 is positioned and the actuator 50 is held, the distance d2 between the nozzle plate part 10 and the vibrating plate 30 can be formed with high precision by removing the temporary determining part 39.

[0171] The location of the temporary determination part 39 is not particularly limited as long as it can ensure the distance d2 between the nozzle plate part 10 and the vibrating plate 30. It can be arranged on the entire surface of the part other than the spacer part 20, or it can be arranged partially on the part of the nozzle plate part 10 opposite to the vibrating plate 30.

[0172] The temporary decision section 39 can be formed by a soluble photoresist. The soluble photoresist can be easily removed by flowing into a resist remover after the inkjet head is assembled. The soluble photoresist can also be a dry film resist that has been used in the past. The dry film resist can be removed using a stripping solution that has been used in the past, such as stripping solution RS-091 manufactured by JCU Corporation.

[0173] The height of the temporary determining part 39 is preferably smaller than the height of the spacer part 20. When using multiple counterweights 34, the multiple counterweights 34 may have dimensional deviations, but by making the height of the temporary determining part 39 smaller than the height of the spacer part 20, even if the multiple counterweights 34 have dimensional deviations, the distance d2 before drive can be the same. Although it depends on the dimensional deviations of the multiple counterweights 34, the height of the temporary determining part 39 is preferably 10% to 30% smaller than the height of the spacer part 20.

[0174] This disclosure also pertains to a printing apparatus equipped with the aforementioned inkjet head and a drive control unit for driving the inkjet head. This printing apparatus can be used for printing with various inks, and is particularly suitable for printing with high-viscosity inks.

[0175] This disclosure also pertains to a method for manufacturing a semiconductor device that includes mounting semiconductors onto a substrate by printing solvent-free ink using the aforementioned printing apparatus. Examples of solvent-free inks include UV-curable inks and solid inks. For example, paraffin wax, which is solid at room temperature, is melted by heating and used as a liquid. According to the aforementioned printing apparatus, high-viscosity inks can be appropriately printed, and solvent-free inks for semiconductor mounting can be appropriately printed. Solvent-free inks are used for mounting semiconductors onto a substrate, such as underfilling, bonding, and buried vias. According to this manufacturing method, high-viscosity solvent-free inks can be printed well, thus facilitating semiconductor mounting onto the substrate.

[0176] Symbol Explanation

[0177] 10—Nozzle plate, 20—Spacer, 30—Vibrating plate, 40—Housing, 50, 50a, 50b—Actuator, 60—Ink chamber, 70—Reservoir, 80—Flexible cable, 11—Nozzle, 12—Protrusion, 13—Support, 14—Beam, 21—Opening, 22—Slit, 23—Tongue, 31—Spring, 31a—Beam, 31b—Base, 31c—Protrusion, 32, 32a—Positioning, 33—Thin plate, 33a—Base on thin plate, 34—Weight, 35—Ink supply hole, 36—Ink discharge hole, 37—Adjustment, 38—Helical spring, 39—Temporary determination, 41, 42—Ink flow path, 43, 44—Air discharge path, 51—Actuator base plate.

Claims

1. An inkjet head, comprising: a nozzle plate portion in which nozzles that eject ink droplets are formed; a vibrating plate disposed opposite an inlet of the nozzles; a weight disposed in contact with the vibrating plate; and an actuator that abuts against the weight, the weight being caused to fly by driving the actuator in accordance with a drive signal, and causing ink in an ink chamber formed between the nozzle plate portion and the vibrating plate to be ejected from the nozzles. The inkjet head according to claim 1, wherein The housing chamber in which the actuator is disposed is separated from the ink chamber by the vibrating plate, The ink chamber has an ejection region that includes the inlet of the nozzles, and a storage region adjacent to the ejection region, The gap between the nozzle plate portion and the vibrating plate is smaller in the ejection region than in the storage region.

2. The inkjet head according to claim 1, wherein The gap in the ejection region is in a range of 1 μm or more and 50 μm or less.

3. The inkjet head according to claim 1 or 2, wherein The viscosity of the ink is in a range of 20 mPa s or more.

4. The inkjet head according to claim 1 or 2, wherein The vibrating plate is composed of a laminated structure of a beam-shaped spring portion and a thin plate portion, and the thin plate portion is composed of a sheet material having flexibility.

5. The inkjet head according to claim 4, wherein A portion of the spring portion that is opposite the inlet of the nozzles is formed to have a wide width.

6. The inkjet head according to claim 4, wherein The weight is in a spherical shape, and is fitted and positioned in a positioning portion provided in the spring portion.

7. The inkjet head according to claim 4, wherein The weight is in a spherical shape, and is positioned in a seat provided in a main surface of the thin plate portion on the housing chamber side.

8. The inkjet head according to claim 7, wherein The spring portion has a protrusion portion on a main surface on the nozzle side in a manner opposite the inlet of the nozzles, and the protrusion portion is configured to be capable of being inserted into the inlet of the nozzles with a gap.

9. The inkjet head according to claim 1 or 2, wherein An ink supply hole is formed through the vibrating plate, and the ink is supplied to the ink chamber via the ink supply hole.

10. The inkjet head according to claim 1 or 2, wherein A plurality of combinations of the actuator and the weight are provided, A spacer portion is provided between the nozzle plate portion and the vibrating plate, The spacer portion is provided between adjacent ones of the plurality of actuator and weight combinations.

11. The inkjet head according to claim 10, wherein A support member that supports the nozzle plate portion is provided, The support member is fixed to a laminated structure that includes the nozzle plate portion, the spacer portion, and the vibrating plate.

12. The inkjet head according to claim 11, wherein The support member is a non-driving portion that is integral with the actuator.

13. The inkjet head according to claim 4, wherein A plurality of combinations of the actuator and the weight are provided, A spacer portion is provided between the nozzle plate portion and the vibrating plate, The beam is provided on the main surface of the thin plate portion on the side of the housing chamber, and the pillar is provided on the main surface of the thin plate portion on the side of the ink chamber. The beam and the pillar are opposed to each other with the thin plate portion interposed therebetween and are bonded to the thin plate portion. The pillar is also bonded to the nozzle plate portion.

14. The ink jet head according to claim 10, wherein The spacer portion is composed of a cured product of a photosensitive thin film resist fixed to the nozzle plate portion and the vibration plate.

15. The ink jet head according to claim 1 or 2, wherein The nozzle plate portion has a flow path for discharging the ink branched from the nozzle within the nozzle plate portion.

16. A printing device characterized by comprising: comprises: the ink jet head according to any one of claims 1 to 15; and a drive control portion that drives the ink jet head.

17. A method for manufacturing a semiconductor device, characterized by mounting a semiconductor on a substrate by printing a solventless ink using the printing apparatus according to claim 16.

18. A method for manufacturing an ink jet head, which is the method for manufacturing an ink jet head according to any one of claims 10 to 14, characterized by arranging a photosensitive thin film resist having adhesiveness on the nozzle plate portion or the vibration plate, performing pattern formation by exposing and developing the photosensitive thin film resist, arranging the vibration plate or the nozzle plate portion on the photosensitive thin film resist after the pattern formation, performing post-baking on a laminate including the nozzle plate portion, the photosensitive thin film resist, and the vibration plate to cure the photosensitive thin film resist as the spacer portion, and forming a laminate in which the nozzle plate portion and the vibration plate are bonded with the spacer portion interposed therebetween.

19. The method for manufacturing an ink jet head according to claim 18, characterized by providing a temporary decision portion that defines the gap between the nozzle plate portion and the vibration plate, between the nozzle plate portion and the vibration plate, and removing the temporary decision portion after the actuator and the weight are arranged on the vibration plate and the ink jet head is assembled.

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