Liquid ejection head and method for manufacturing liquid ejection head

Abstract

An object of the technique of the present disclosure is to provide a highly reliable liquid ejection head in which a nozzle is less likely to be damaged.SOLUTION: The liquid ejection head of the present disclosure is configured to be capable of performing recording by ejecting a liquid onto a recording medium. The liquid discharge head includes a nozzle forming member in which a nozzle for discharging a liquid is formed, and a protrusion protruding from a surface of the nozzle forming member in a direction in which the nozzle discharges the liquid. A base end of the convex portion is embedded in the nozzle forming member.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In a liquid ejection head that performs recording by ejecting liquid from a nozzle onto a recording medium, a step may be formed near the nozzle to protect the nozzle from contact with the outside.

[0003] Patent Document 1 discloses a liquid ejection head in which part of a liquid-repellent film formed on the ejection surface (ejection port surface) of a nozzle plate (nozzle forming member) is removed, and a convex portion (step) is formed in the removed portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-208349 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the case of the protrusions formed by the method of Patent Document 1, if a strong impact is applied for some reason, the protrusions may peel off.

[0006] Therefore, an object of the present disclosure is to provide a highly reliable liquid ejection head in which nozzle damage is unlikely to occur. [Means for solving the problem]

[0007] The liquid ejection head of the present disclosure comprises a nozzle for ejecting liquid and a nozzle forming member having the nozzle, and is characterized in that a portion of a convex portion that protrudes above the surface of the nozzle forming member is embedded in the nozzle forming member. [Effects of the Invention]

[0008] According to the technology of the present disclosure, it is possible to provide a highly reliable liquid ejection head in which nozzle damage is unlikely to occur. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view of the liquid ejection head according to the embodiment, seen from the rear bottom surface. [Figure 2] FIG. 2 is a schematic partial cross-sectional view of a recording element substrate according to an embodiment. [Figure 3] FIG. 3 is a schematic bottom view of a recording element substrate. [Figure 4] FIG. 10 is a schematic diagram showing an example of cleaning. [Figure 5] 10 is a flowchart showing an example of a method for manufacturing a recording element substrate. [Figure 6] 5A to 5C are explanatory diagrams illustrating steps of a method for manufacturing a recording element substrate. [Figure 7] 10A and 10B are diagrams showing modified examples of the liquid ejection head. [Figure 8] FIG. 10 is a diagram showing a modified example of the liquid ejection head. [Figure 9] 10 is a flowchart showing an example of a method for manufacturing a recording element substrate. [Figure 10] FIG. 4 is an explanatory diagram of one step of a method for manufacturing a recording element substrate. [Figure 11] FIG. 2 is a schematic cross-sectional view of a recording element substrate according to an embodiment. [Figure 12] 10A to 10C are explanatory diagrams illustrating a modified example of the steps of the method for manufacturing the recording element substrate. [Figure 13] FIG. 4 is an explanatory diagram of one step of a method for manufacturing a recording element substrate. [Figure 14] FIG. 10 is an explanatory diagram of a coating step of a third resin in one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] [First embodiment] <Liquid ejection head 100> FIG. 1 is a perspective view of a liquid ejection head 100 that can be applied to this embodiment, seen from the rear bottom surface.

[0011] The coordinate axes in the figure will be explained. The ±X direction indicates the longitudinal direction of the liquid ejection head 100, i.e., the direction in which multiple nozzles are arranged. The ±Y direction indicates the depth direction of the liquid ejection head 100. The -Y direction corresponds to the transport direction of the recording medium 208 (see Figure 2, etc.). The -Y direction will be referred to as the transport direction as appropriate. The Z direction indicates the height direction of the liquid ejection head 100. The -Z direction corresponds to the direction in which liquid is ejected from the liquid ejection head 100.

[0012] In this embodiment, the description will be made assuming that the "liquid" is ink. However, the liquid that can be used in this embodiment is not limited to ink. In other words, various recording liquids may be used, including treatment liquids that are used for the purposes of improving the fixation of ink on a recording medium, reducing uneven gloss, or improving abrasion resistance.

[0013] "Recording" (also called "printing") does not only mean forming meaningful information such as letters and figures. "Recording" also means forming meaningless information such as images, designs, or patterns. Furthermore, "recording" does not matter whether it is something that is visible to humans or not. In other words, "recording" also means forming a structure on a recording medium or processing the medium.

[0014] As shown in FIG. 1, the liquid ejection head 100 includes a recording element substrate 101 capable of ejecting liquid (for example, ink).

[0015] In this embodiment, the liquid ejection head 100 is capable of full-color recording using cyan, magenta, yellow, and black ink. However, recording using inks of colors other than these four may also be performed. For example, monochrome recording using black ink may also be performed.

[0016] In this embodiment, a plurality of recording element substrates 101 are arranged linearly (in-line) along the X direction. Each recording element substrate 101 is electrically connected to an electric wiring board 103 via a flexible wiring board 102. The electric wiring board 103 includes a signal input terminal (not shown) and a power supply terminal (not shown).

[0017] The signal input terminal and the power supply terminal are electrically connected to a control unit (for example, a CPU, not shown) of the liquid ejection device when the liquid ejection head 100 is attached to the main body (not shown) of the liquid ejection device. The signal input terminal and the power supply terminal supply an ejection drive signal and power required for ejection to the recording element substrate 101, respectively.

[0018] By consolidating the wiring using an electric circuit provided inside the electric wiring board 103, the number of signal input terminals and power supply terminals can be made smaller than the number of recording element boards 101. With this configuration, when assembling the liquid ejection head 100 to the liquid ejection device or when replacing the liquid ejection head 100, the number of electrical connection parts that need to be removed can be reduced.

[0019] Furthermore, the electrical connection portions of the recording element substrate 101 and the flexible wiring substrate 102 are sealed with a first sealing material 104. On the other hand, the electrical connection portions of the flexible wiring substrate 102 and the electrical wiring substrate 103 are sealed with a second sealing material 105. The recording element substrate 101 is fixed by an adhesive (not shown) to a base 106, which has a flow path formed therein for passing ink. There are multiple adhesive portions between the recording element substrate 101 and the base 106.

[0020] Ink is supplied to the base 106 through a housing 107. The base 106 and the flexible wiring board 102 are covered by a cover 109 having an opening 108. The recording element substrate 101 is exposed from the opening 108 of the cover 109. The edge of the opening 108 is sealed with a curable liquid material so as to be approximately flat.

[0021] FIG. 2 is a schematic partial cross-sectional view of a recording element substrate 101 that can be applied to this embodiment.

[0022] As shown in FIG. 2, the recording element substrate 101 includes a nozzle forming member 202 in which nozzles 201 for ejecting liquid are formed, a substrate 203 made of silicon, and a convex portion 204 that protrudes from the lower surface of the substrate 203 beyond the lower surface of the nozzle forming member 202.

[0023] A portion of the protrusion 204 is embedded in the nozzle forming member 202. In this embodiment, the depth to which the base end of the protrusion 204 is embedded in the nozzle forming member 202 (the length in the Z direction in FIG. 2) is approximately equal to the thickness of the nozzle forming member 202 (the length in the Z direction in FIG. 2).

[0024] The nozzle forming member 202 is formed with a pressure chamber 205 that receives pressure when liquid is ejected from the nozzle 201. The nozzle 201 is formed so as to be connected to the pressure chamber 205. A substrate 203 is laminated on the upper surface of the nozzle forming member 202. The substrate 203 is formed with a flow path 206 for supplying liquid to the pressure chamber 205 of the nozzle forming member 202, and is provided with a heater 207 that is a heat generating resistance element.

[0025] With the lower surface of the substrate 203 bonded to the upper surface of the nozzle forming member 202, the heater 207 is provided at a position facing the nozzle 201, and the flow path 206 is connected to the pressure chamber 205. A pulse signal of a constant power is supplied to the heater 207 through electrical wiring (not shown).

[0026] In this embodiment, power is supplied to the heater 207 in the form of extremely short pulses. For example, power is supplied to the heater 207 with a pulse width of approximately 0.1 μsec to 10.0 μsec. By supplying power to the heater 207 in this manner, film boiling occurs in the liquid filled inside the pressure chamber 205. The resulting bubbling energy then causes the liquid to be ejected from the nozzle 201.

[0027] However, if for some reason the recording medium 208 is transported in a deformed state, the recording medium 208 may come into contact with the nozzle 201, possibly scraping off the nozzle 201. For example, if glossy paper containing inorganic particle components with a relatively high rigidity is used as the recording medium 208 and a paper jam occurs, the nozzle 201 may be scraped off by the glossy paper that has been deformed by the paper jam.

[0028] Therefore, in this embodiment, a convex portion 204 is provided near the nozzle 201 to prevent the nozzle 201 from being scraped by the recording medium 208. With this configuration, even if the deformed recording medium 208 approaches the nozzle 201, the protruding convex portion 204 comes into contact with the deformed recording medium 208 and pushes it back, thereby preventing the nozzle 201 from being damaged.

[0029] However, in the configuration of Patent Document 1, the convex structure (convex portion) was adhered to the underside of the nozzle forming member 202, so if the glossy paper came into contact with the convex structure with a relatively strong force, there was a risk that the convex structure would peel off.

[0030] In contrast to this, in this embodiment, the upper surface of the convex portion 204 is bonded to the lower surface of the substrate 203, the base end of the convex portion 204 is embedded in the nozzle forming member 202, and the tip end of the convex portion 204 protrudes downward from the lower surface of the nozzle forming member 202. In other words, the convex portion 204 in this embodiment is supported from its side by the nozzle forming member 202.

[0031] 2 indicates the height of the base end of the convex portion 204. "H1" in FIG. 2 indicates the height of the tip end of the convex portion 204. The height of the base end of the convex portion 204 is the same as the thickness of the nozzle forming member 202. With this configuration, the base end of the convex portion 204 is embedded in the nozzle forming member 202, and therefore, the convex portion 204 can withstand the impact that occurs when the recording medium 208 comes into contact with it better than the configuration of Patent Document 1. Therefore, compared to the configuration of Patent Document 1, the risk of the convex portion 204 peeling off can be reduced even when the convex portion 204 comes into contact with glossy paper.

[0032] It is preferable that the protrusion 204, the first sealing material 104 (see FIG. 1), and the second sealing material 105 (see FIG. 1) are made of the same material (for example, a thermosetting epoxy resin). This configuration allows the use of standardized materials, which reduces the amount of work required compared to when these components are made from different materials.

[0033] Furthermore, the modulus of elasticity of the convex portions 204 is preferably 2 GPa (gigapascals) or more. This configuration allows them to withstand the impact that occurs when the recording medium 208 comes into contact with them. It is even more preferable that the modulus of elasticity of the convex portions 204 is 4 GPa or more. This configuration allows them to withstand with even greater ease the impact that occurs when the recording medium 208 comes into contact with them.

[0034] FIG. 3 is a schematic bottom view of the recording element substrate 101. As shown in FIG.

[0035] 3, the recording medium 208 (see FIG. 2) is transported in the -Y direction. Therefore, by providing the convex portions 204 so as to extend along the direction in which the nozzles 201 are arranged (±X direction), which is perpendicular to the transport direction, the nozzles 201 can be protected.

[0036] In this embodiment, the convex portion 204 is arranged so as to be parallel to one nozzle row 301 formed by arranging a plurality of nozzles 201 along the X direction. Note that in this embodiment, the plurality of nozzle rows 301 are arranged along the transport direction (Y direction), and one convex portion 204 is provided between two adjacent nozzle rows 301.

[0037] An example of dimensions of a configuration applicable to this embodiment will be described below. The pitch "P1" between two nozzles may be within a range of 20 to 500 μm. The diameter "d" of the nozzle 201 may be within a range of 5 to 100 μm. The distance "L" from the end of the nozzle 201 to the convex portion 204 in the Y direction may be greater than 20 μm and less than 500 μm. It is more preferable that the distance "L" be 50 μm or greater and 200 μm or less. The shorter the distance "L", the better the guarding effect for protecting the nozzle 201.

[0038] However, on the other hand, when the material that forms the convex portion 204 is applied, there is a risk that the material will adhere to the nozzle 201. Therefore, by setting the distance "L" to 50 μm or more, it is possible to almost completely eliminate the risk that the material that forms the convex portion 204 will adhere to the nozzle 201 when it is applied.

[0039] Furthermore, if the distance "L" is 500 μm or more, there is almost no effect of protecting the nozzle 201. If the distance "L" is 200 μm or less, the effect of protecting the nozzle 201 becomes extremely large.

[0040] 3 indicates the pitch between two nozzle rows in the Y direction. The width "W" of the convex portion 204 is automatically determined by determining the pitch "P2" and the distance "L." For example, the width "W" of the convex portion 204 can be calculated using the following formula (1):

[0041] (Formula 1) W = Pitch "P2" - (Distance "L" x 2)

[0042] The pitch "P2" varies depending on the internal structure of the recording element substrate 101 and the conditions for image formation. The pitch "P2" may be 200 μm or more and 2000 μm or less.

[0043] FIG. 4(a) is a schematic diagram showing a state in which the nozzle 201 is being cleaned using a blade 401 that can be applied to this embodiment.

[0044] 4(a), the blade 401 is configured to be able to remove foreign matter 402 (for example, ink adhering to the nozzle surface) while moving along the blade traveling direction (X direction). Note that in this embodiment, it is possible to use one blade 401 to clean multiple nozzle rows 301 at once.

[0045] FIG. 4(b) is a schematic cross-sectional view showing how the foreign matter 402 is properly removed.

[0046] 4(b), when the height "H1" of the convex portion 204 is an appropriate dimension, the blade 401 can be used to remove foreign matter 402 adhering to the vicinity of the nozzle 201. The height "H1" of the convex portion 204 may be 10 μm or more and 100 μm or less. It is more preferable that the height "H1" of the convex portion 204 is more than 20 μm and less than 60 μm.

[0047] Assume that the distance "L" is greater than 20 μm and less than 500 μm, and the width "W" of the convex portion 204 is within the range of dimensions that can be calculated using the above formula (1). In this case, if the height "H1" is 60 μm or more, it becomes increasingly difficult for the blade 401 to reach the nozzle surface, and the cleaning ability of the nozzle 201 tends to decrease. If the height "H1" is 20 μm or less, the effect of protecting the nozzle 201 decreases. It is preferable that the height "H2" be 3 μm or more.

[0048] When the base end of the convex portion 204 is buried in the nozzle-forming member 202 by 3 μm or more, the convex portion 204 is more firmly fixed than in a configuration in which the convex portion 204 is not buried in the nozzle-forming member 202. It is more preferable that the height "H2" is 5 μm or more. When a portion of the convex portion 204 is buried in the nozzle-forming member 202 by 5 μm or more, the convex portion 204 is more firmly fixed than in a configuration in which the convex portion 204 is buried in the nozzle-forming member 202 by 3 μm.

[0049] FIG. 4C is a schematic cross-sectional view showing a reference example of removing the foreign matter 402.

[0050] 4(c), from the viewpoint of protecting the nozzle 201, the higher the height "H1" of the convex portion 204, the better. However, if the dimension of the height "H1" of the convex portion 204 is too large, the blade 401 will not reach the nozzle surface, making it difficult to remove the foreign matter 402. Therefore, it is preferable that the height "H1" of the convex portion 204 be configured to fall within the above-mentioned dimension.

[0051] 5 is a flowchart showing a method for manufacturing the recording element substrate 101 that can be applied to this embodiment. In FIG. 5, the symbol "S" represents a step. 6(a) to 6(d) are explanatory diagrams illustrating the steps of a method for manufacturing the recording element substrate 101 that can be applied to this embodiment. Below, the manufacturing process for the recording element substrate 101 will be described along with FIG. 5, with reference to FIGS. 6(a) to 6(d).

[0052] In S501, a substrate 203 having a flow channel 206 and a heater 207 is prepared.

[0053] Fig. 6(a) is an explanatory diagram of S501. For convenience of explanation, the surface facing upward in Fig. 6(a) will be referred to as the upper surface in the following explanation.

[0054] 6(a), in S501, a substrate 203 is prepared that includes a channel 206 and a heater 207. A plurality of channels 206 and a plurality of heaters 207 are arranged in the vertical direction in the drawing.

[0055] Wiring (not shown) is provided on the substrate 203 so that the heater 207 can be driven as desired, and a flow path 206 is formed thereon. An example of a method for forming the wiring including the heater 207 is photolithography technology for forming semiconductor elements. An example of a method for forming the flow path 206 is dry etching. Other examples of a method for forming the flow path 206 include wet etching and sandblasting. The explanation will be continued below with reference to FIG. 5 again. After S501, S502 is performed.

[0056] In S502, a first resin 601 in the form of a dry film is placed on the upper surface of the substrate 203. The first resin 601 is a negative ultraviolet curable resin. From the viewpoint of ink resistance, it is preferable to use an epoxy resin as the first resin 601. In this embodiment, a cationically polymerized epoxy resin is used as the first resin 601.

[0057] The thickness of the first resin 601 (see FIG. 6(b)) placed on the upper surface of the substrate 203 is the same as the height of the pressure chambers 205 (see FIG. 2, etc.) in the nozzle forming member 202 (see FIG. 2, etc.). In this embodiment, the nozzle forming member 202 is composed of a layer for forming the pressure chambers 205 and a layer for forming the nozzles 201 (see FIG. 2, etc.). When the first resin 601 hardens, a layer for forming the pressure chambers 205 in the nozzle forming member 202 is formed.

[0058] In S503, the first resin 601 is masked using a first mask 602 (see FIG. 6(b)). The first mask 602 masks a first planned portion 603 (see FIG. 6(b)) for forming holes 611 (see FIG. 6(d)) for applying a third resin that will form the convex portion 204 (see FIG. 2, etc.). The first mask 602 also masks a second planned portion 604 (see FIG. 6(b)) for forming the pressure chamber 205 (see FIG. 2, etc.). The description will be continued below, again with reference to FIG. 5. After S503, S504 is performed.

[0059] In S504, the upper surface of the first resin 601 is irradiated with first ultraviolet rays 605 (see FIG. 6(b)) to harden the first resin 601.

[0060] Fig. 6(b) is an explanatory diagram of S504. For the sake of convenience, the surface facing upward in Fig. 6(b) will be referred to as the upper surface in the following description.

[0061] As shown in Fig. 6(b), in S504, first ultraviolet light 605 is irradiated onto the upper surface of the first resin 601 through the first mask 602. This causes the unmasked portions of the first resin 601 to harden. The description will be continued below with reference to Fig. 5 again. After S504, S505 is performed.

[0062] In S505, the above-mentioned second resin 606 (see FIG. 6(c)) is applied by spin coating to the upper surface of the first resin 601 (see FIG. 6(c)). Like the first resin 601, the second resin 606 is also a negative ultraviolet curable resin. When the second resin 606 is cured, one of the two layers that make up the nozzle forming member 202 is formed, which is the layer that forms the nozzle 201 (see FIG. 2, etc.). The description will be continued below, again with reference to FIG. 5. After S505, S506 is performed.

[0063] In S506, the second resin 606 is masked using a second mask 607 (see FIG. 6(c)). The second mask 607 masks a third planned portion 608 (see FIG. 6(c)) for forming a hole 611 for applying the above-mentioned third resin, and a fourth planned portion 609 (see FIG. 6(b)) for forming a nozzle 201 (see FIG. 2, etc.). The description will be continued below with reference to FIG. 5 again. After S506, S507 is performed.

[0064] In S507, the upper surface of the second resin 606 is irradiated with second ultraviolet light 610 (see FIG. 6(c)), thereby hardening the second resin 606.

[0065] FIG. 6C is an explanatory diagram of S507.

[0066] As shown in Figure 6(c), in S507, second ultraviolet light 610 is irradiated onto the upper surface of the second resin 606 through the second mask 607. This causes the unmasked portions of the second resin 606 to harden. The description will be continued below with reference to Figure 5 again. After S507, S508 is performed.

[0067] In S508, the first resin 601 and the second resin 606 are subjected to a development process to form the nozzle forming member 202.

[0068] FIG. 6D is an explanatory diagram of S508.

[0069] As shown in FIG. 6(d), the nozzle forming member 202 has holes 611 for applying a third resin that forms the pressure chambers 205, the nozzles 201, and the convex portions 204 (see FIG. 2, etc.). By the development process, the first planned portion 603 (see FIG. 6(b)) and the second planned portion 604 (see FIG. 6(b)) are washed away from the first resin 601. Then, the third planned portion 608 (see FIG. 6(c)) and the fourth planned portion 609 (see FIG. 6(c)) are washed away from the second resin 606.

[0070] In this manner, the uncured portions of the first resin 601 and the second resin 606 are washed away, thereby forming the pressure chambers 205 and the nozzles 201 in the second predetermined portion 604 and the fourth predetermined portion 609, respectively. Then, the first predetermined portion 603 and the third predetermined portion 608 are washed away, thereby forming the holes 611. That is, in S508, the first resin 601 and the second resin 606 are subjected to a development process, thereby simultaneously forming the pressure chambers 205, the nozzles 201, and the holes 611 in the nozzle forming member 202. The description will be continued below with reference to FIG. 5 again. After S508, S509 is performed.

[0071] In S509, a liquid third resin having thermosetting properties is applied to the inside of the hole 611 (see FIG. 6(d)). In S509, the third resin is applied to a desired height. From the viewpoint of ink resistance, the third resin is preferably an epoxy resin. In S509, the third resin may be applied by a dispenser, or may be applied by screen printing, jet dispensing, or the like.

[0072] The viscosity of the third resin during application is preferably 50 Pa·s (Pascal seconds) or more and 1000 Pa·s or less. If the viscosity of the third resin is within this range, it is possible to form a convex shape that protrudes outward from the nozzle surface to a desired height.

[0073] Furthermore, it is more preferable that the viscosity of the third resin during application be 100 Pa·s or more and 500 Pa·s or less. If the viscosity of the third resin is within this range, it becomes easier to mold the third resin into a convex shape. The explanation will be continued below, again with reference to FIG. 5. After S509, S510 is performed.

[0074] In S510, the third resin is heated. As described above, the third resin has thermosetting properties. Therefore, when the third resin is heated, the third resin hardens. By hardening the third resin, the convex portion 204 is completed.

[0075] FIG. 6(e) is an explanatory diagram of S510.

[0076] 6(e), the substrate 203, the nozzle forming member 202, and the convex portion 204 are separate members. Therefore, when viewing the cross section of the recording element substrate 101, it can be seen that the bottom surface of the convex portion 204 is fixed to the upper surface of the substrate 203.

[0077] Furthermore, a boundary line appears between the nozzle forming member 202 and the convex portion 204. Therefore, even if the color of the nozzle forming member 202 and the color of the convex portion 204 are the same, by looking at the cross section of the recording element substrate 101, it can be seen that the base end of the convex portion 204 is embedded in the hole 611 (see FIG. 6(d)) of the nozzle forming member 202.

[0078] As described above, in the liquid ejection head of this embodiment, the base ends of the convex portions are formed in a state where they are embedded in the nozzle forming member.

[0079] With this configuration, the lower surface of the convex portion (the surface facing downward in FIG. 6(e)) is fixed, compared to a configuration in which the convex portion is fixed to the ejection port surface (i.e., the surface of the nozzle forming member 202). Furthermore, part of the outer peripheral surface of the convex portion is fixed to the inner peripheral surface of the hole formed in the nozzle forming member. Therefore, compared to a configuration in which the convex portion is fixed to the ejection port surface, the area to which the convex portion is fixed can be increased. Therefore, even if a recording medium or the like collides with the convex portion, the convex portion is more likely to withstand the impact.

[0080] Therefore, according to the technology of this embodiment, it is possible to provide a highly reliable liquid ejection head.

[0081] In the liquid ejection head of Patent Document 1, convex portions are formed in the areas where the liquid-repellent film has been removed. In other words, in the liquid ejection head of Patent Document 1, it is difficult to form convex portions unless a liquid-repellent film is first formed and then a portion of the liquid-repellent film is removed to define the area where the convex portions are to be formed. In this embodiment, convex portions can be formed regardless of whether or not a liquid-repellent film is present, which provides greater freedom in forming convex portions compared to the liquid ejection head of Patent Document 1.

[0082] Furthermore, even when forming a liquid-repellent film, there is no need to remove the liquid-repellent film once it has been formed in order to define the areas where the convex portions are to be formed, and therefore the manufacturing method of this embodiment produces less waste than the manufacturing method of Patent Document 1. In this way, according to the technology of this embodiment, even when forming a liquid-repellent film, it is possible to provide a highly reliable liquid ejection head without wasting the liquid-repellent film.

[0083] [Modification of the first embodiment] 7(a) to 7(e) are diagrams showing modified examples of the liquid ejection head of the first embodiment.

[0084] FIG. 7A is a diagram showing a first modified example of the liquid ejection head of the first embodiment.

[0085] As shown in Figure 7(a), when the recording element substrate 101 is viewed in plan, multiple convex portions 204 may be formed in a dashed line shape along a direction intersecting the transport direction. Even with this configuration, a highly reliable liquid ejection head can be provided. With this configuration, the amount of the third resin that constitutes the convex portions 204 can be reduced compared to the example in Figure 3, thereby reducing costs.

[0086] FIG. 7B is a diagram showing a second modified example of the liquid ejection head of the first embodiment.

[0087] 7(b), in a plan view of the recording element substrate 101, the plurality of convex portions 204 may be dotted in a dot pattern along a direction intersecting the transport direction. Even with this configuration, a highly reliable liquid ejection head can be provided. With this configuration, compared to the first modification, the amount of the third resin that constitutes the convex portions 204 can be reduced, further reducing costs.

[0088] FIG. 7C is a diagram showing a third modified example of the liquid ejection head of the first embodiment.

[0089] 7(c), in a plan view of the recording element substrate 101, convex portions 204 having portions extending along the transport direction may be formed outside the ends of the nozzle row 301 so as to connect portions extending in a direction intersecting the transport direction. With this configuration, compared to the example in FIG. 3, it is easier to protect the nozzles 201 located at both ends of the nozzle row, and a more reliable liquid ejection head can be provided.

[0090] FIG. 7D is a diagram showing a fourth modified example of the liquid ejection head of the first embodiment.

[0091] 7(d), in a plan view of the recording element substrate 101, the convex portions 204 may be formed outside the ends of the nozzle array 301, each having a portion extending along the transport direction so as not to connect the portions extending along a direction intersecting the transport direction. With this configuration, compared to the third modification, the amount of the third resin that constitutes the convex portions 204 to be applied can be reduced, resulting in cost savings.

[0092] FIG. 7(e) is a diagram showing a fifth modified example of the liquid ejection head of the first embodiment.

[0093] 7(e), when the pitch between two nozzles is relatively large, a grid-shaped convex portion 204 may be formed so as to surround one nozzle 201 when the recording element substrate 101 is viewed in plan. In this way, when the pitch between two nozzles is relatively large, the convex portion 204 may be formed so as to extend not only parallel to the nozzle row 301 but also so as to pass between the two nozzles. With this configuration, compared to the example in FIG. 3, the formation of the convex portion 204 between the two nozzles further improves the protection of the nozzle 201.

[0094] FIG. 8 is a diagram showing a sixth modified example of the liquid ejection head of the first embodiment.

[0095] 6(d), in order to apply the third resin, holes 611 that penetrate the nozzle forming member 202 in the Z direction are formed in the nozzle forming member 202 in the orientation for manufacturing the recording element substrate 101. However, the region for applying the third resin is not limited to the holes 611 that penetrate the nozzle forming member 202.

[0096] In the example shown in FIG. 8, the depth to which the convex portion 204 is embedded in the nozzle forming member 202 (length extending in the Z direction in FIG. 8) is approximately equal to the length of the nozzle 201 (length extending in the Z direction in FIG. 8).

[0097] In this way, in order to apply the third resin that constitutes the protrusions 204, recesses 800 that are approximately equal to the length of the nozzles 201 may be formed in the second resin 606 that constitutes the nozzle forming member 202. Also, regardless of the length of the nozzles 201, recesses 800 may be formed that are shorter than the thickness of the nozzle forming member 202. In other words, the area for applying the third resin need only be a hole with a depression, and does not have to be a through-hole. Then, the protrusions 204 can be formed by applying the third resin to the recesses 800. Even with this configuration, a highly reliable liquid ejection head can be provided.

[0098] [Second embodiment] The present embodiment aims to provide a liquid ejection head that can further improve the protection of the nozzles. In the following description, the same reference numerals are used to designate the same or corresponding components as those in the first embodiment, and a description thereof will be omitted, with differences being mainly described.

[0099] FIG. 9 is a flowchart showing a method for manufacturing the recording element substrate 101 that can be applied to this embodiment.

[0100] As shown in FIG. 9, in this embodiment, S900 is performed after S509 and before S510.

[0101] In S900, a flat surface is formed on the third resin.

[0102] FIG. 10 is an explanatory diagram of S900.

[0103] 10 , in this embodiment, after forming the convex shape of the third resin to form the convex portion 204, the tip of the third resin is scraped off with a scraper 1000 to form a flat surface. If the dispenser needle used when applying the third resin is used as the scraper 1000, a flat surface can be efficiently formed on the third resin. Note that, as long as a flat surface can be formed on the third resin, a device other than the device used when applying the third resin may be used as the scraper 1000.

[0104] FIG. 11 is a schematic cross-sectional view of a recording element substrate 101 that can be applied to this embodiment.

[0105] 11, the cross-sectional shape of the tip of the convex portion 204 in this embodiment that protrudes beyond the ejection port surface of the nozzle forming member 202 is approximately trapezoidal. By making the tip of the convex portion 204 flat, the tip of the convex portion 204 can be angled so that it protrudes from the outside toward the inside. This makes it less likely that the recording medium 208 will come into contact with the nozzle 201 compared to the first embodiment, in which the tip is round, even if the amount of protrusion from the ejection port surface is the same as in the first embodiment.

[0106] Therefore, according to the liquid ejection head of this embodiment, it is possible to further improve the protection of the nozzles.

[0107] [Modification of the second embodiment] Fig. 12 is a diagram showing a modified example of S900. In the example of Fig. 10, the flat surface is formed by scraping off the tip of the third resin with a scraper 1000 (see Fig. 10). However, the method for forming the flat surface on the third resin is not limited to this method.

[0108] As shown in Fig. 12, a pressing member 1200 may be used to press the third resin from its tip toward its base end to form a flat surface. The material constituting the pressing member 1200 includes a fluororesin. The pressing surface of the pressing member 1200 that presses the third resin is treated with a liquid-repellent coating. With this configuration, even when a third resin with a relatively high viscosity is pressed to form a convex shape, the pressing member 1200 can be easily released from the third resin.

[0109] In the example of Fig. 12, flat surfaces are formed on multiple third resins using one pressing member 1200. This method of forming multiple flat surfaces at once improves productivity. However, a flat surface may also be formed on one third resin using one pressing member 1200. This method also allows a flat surface to be formed on the tip of the third resin.

[0110] [Third embodiment] The present embodiment aims to provide a liquid ejection head with higher reliability. In the following description, the same reference numerals are used to designate components similar to or corresponding to those in the first and second embodiments, and a description thereof will be omitted, with differences being mainly described.

[0111] In S503 (see Figure 5) of this embodiment, in addition to the portion masked in the first embodiment, at least one side of the first planned portion 603 (see Figure 6(b)) is masked by a first mask 602 (see Figure 6(b)).

[0112] In S506 (see Figure 5) of this embodiment, in addition to the portion masked in the first embodiment, at least one side of the third planned portion 608 (see Figure 6(c)) is masked by a second mask 607 (see Figure 6(c)).

[0113] In S508 (see FIG. 5) of this embodiment, a groove 1300 (see FIG. 13) is formed on at least one side of the hole 611. That is, in this embodiment, the pressure chamber 205, the nozzle 201, the hole 611, and the groove 1300 are simultaneously formed by the development process of S508.

[0114] FIG. 13 is an explanatory diagram of S508 in this embodiment.

[0115] As shown in FIG. 13, the nozzle forming member 202 of this embodiment has a groove 1300 formed on at least one side of the region where the protrusion 204 (see FIGS. 14(a) and (b)) is buried.

[0116] FIG. 14(a) is an explanatory diagram of the third resin application step in this embodiment.

[0117] 14(a), grooves 1300 are formed on at least one side of the region where the protrusions 204 of this embodiment are embedded, for discharging the third resin that has overflowed from the holes 611. By forming the grooves 1300 on both sides of the holes 611 as shown in FIG. 14(a), it is possible to increase the amount of the third resin that can be discharged compared to a configuration in which the grooves 1300 are formed only on one side of the holes 611.

[0118] While the third resin that forms the convex portion 204 is being applied to the hole 611, the third resin may, for some reason or another, overflow from the hole 611. Even if the third resin overflows from the hole 611, the groove 1300 formed on at least one side of the hole 611 allows the overflowing third resin to escape into the groove 1300.

[0119] FIG. 14( b ) is an explanatory diagram of the effect of the groove 1300 .

[0120] 14(b), the amount of overflowing third resin may vary depending on the location where hole 611 is formed. Even if the amount of overflowing third resin varies depending on the location, as long as all of the overflowing third resin can be released into groove 1300, the width "W2" of convex portion 204 will be the same everywhere. In other words, with this configuration, even if the amount of overflowing third resin varies depending on the location, convex portion 204 having a constant width "W2" can be formed with high precision.

[0121] Therefore, according to the technology of this embodiment, it is possible to provide a liquid ejection head with higher reliability.

[0122] [Other embodiments] The order of the steps shown in Fig. 5 may be changed as appropriate, or the steps shown in Fig. 5 may be performed all at once. In the example of Fig. 5, S509 is performed immediately after S508. However, if S509 is performed after S508, another step may be performed between S508 and S509. In this way, the protrusion 204 (see Fig. 2, etc.) can be formed at any time after the hole 611 (see Fig. 6, etc.) is formed.

[0123] The liquid-repellent film preferably has photosensitivity. However, if the liquid-repellent film is sufficiently thin, such as 1 μm or less, the liquid-repellent film does not need to have photosensitivity. This is because if the liquid-repellent film is 1 μm or less in thickness, it can be removed in S508 (development process) in FIG. 5. In this way, the technology of the present disclosure can also be applied to liquid ejection heads in which a liquid-repellent film is formed on the nozzle surface.

[0124] 6(c), no liquid-repellent film is formed on the upper surface of the second resin 606, but a liquid-repellent film may be formed on the upper surface of the second resin 606. It is possible to form the convex portions 204 (see FIG. 2, etc.) regardless of whether or not there is a liquid-repellent film, but by forming a liquid-repellent film on the ejection port surface of the nozzle forming member 202, the liquid repellency of the ejection port surface can be improved compared to when there is no liquid-repellent film.

[0125] In the above embodiment, the heater 207 (see FIG. 2, etc.) is used as a heat generating resistor element that generates energy for ejecting ink. However, a piezoelectric element or other energy generating element may be used as the heat generating resistor element. In this way, ink may be ejected by an ejection method using a piezoelectric element or by other methods.

[0126] Furthermore, in the above embodiment, the nozzle forming member 202 is made of resin, but the material that constitutes the nozzle forming member 202 may be metal or an inorganic material.

[0127] Furthermore, in the above embodiment, the holes 611 (see FIG. 6(d) and the like) are formed by photolithography, but they may also be formed by laser, dry etching, or other methods.

[0128] The present disclosure includes the following configurations and methods.

[0129] [Configuration 1] a nozzle forming member in which a nozzle for ejecting a liquid is formed; a protrusion that protrudes from a surface of the nozzle forming member in a direction in which the nozzle ejects liquid, a base end of the protrusion is embedded in the nozzle forming member; A liquid ejection head characterized by:

[0130] [Configuration 2] a depth to which the protrusion is embedded in the nozzle forming member is substantially equal to a thickness of the nozzle forming member; The liquid ejection head according to configuration 1.

[0131] [Configuration 3] The depth to which the protrusion is embedded in the nozzle forming member is approximately equal to the length of the nozzle. 3. The liquid ejection head according to claim 1 or 2.

[0132] [Configuration 4] The convex portion is made of a thermosetting resin. 4. The liquid ejection head according to any one of the first to third aspects.

[0133] [Configuration 5] The elastic modulus of the protrusions is 2 GPa or more. 5. The liquid ejection head according to any one of the first to fourth aspects.

[0134] [Configuration 6] an electrical connection for receiving electrical power to eject liquid from the nozzle; a sealing material that seals the electrical connection portion; Further provided with The convex portion and the sealing material are made of the same material. 6. The liquid ejection head according to any one of the first to fifth aspects.

[0135] [Configuration 7] When the liquid ejection head is viewed from the ejection direction, the convex portion is formed parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction. 7. The liquid ejection head according to any one of the first to sixth aspects.

[0136] [Configuration 8] When the liquid ejection head is viewed from the ejection direction, the convex portion is arranged in a dashed line parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction. 8. The liquid ejection head according to any one of the first to seventh aspects.

[0137] [Configuration 9] When the liquid ejection head is viewed from the ejection direction, the convex portions are formed in a dotted pattern along a nozzle row in which the nozzles are arranged in a first direction. 9. The liquid ejection head according to any one of the first to eighth aspects.

[0138] [Configuration 10] When the liquid ejection head is viewed from the ejection direction, the convex portion has a region formed parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction, and a region extending in a second direction that is outside the nozzle row in the first direction and intersects the first direction on a plane. 10. The liquid ejection head according to any one of the first to ninth aspects.

[0139] [Configuration 11] When the liquid ejection head is viewed from the ejection direction, the convex portion is formed so as to surround the nozzle. 11. The liquid ejection head according to any one of the first to tenth aspects.

[0140] [Configuration 12] a cross-sectional shape of a region of the convex portion that protrudes beyond the nozzle forming member is substantially trapezoidal; 12. The liquid ejection head according to any one of the first to eleventh aspects.

[0141] [Configuration 13] a groove is formed in the nozzle forming member on at least one side of a region in which the protrusion is buried; 13. The liquid ejection head according to any one of the first to second aspects.

[0142] [Configuration 14] The nozzle forming member has grooves formed on both sides of an area where the protrusions are embedded. 14. The liquid ejection head according to claim 13.

[0143] [Configuration 15] a liquid-repellent film is formed on the surface of the nozzle forming member; 15. The liquid ejection head according to any one of the first to fourteenth aspects.

[0144] [Configuration 16] a substrate laminated on the nozzle forming member and provided with an energy generating element for ejecting liquid from the nozzle, The base end of the protrusion is in contact with the substrate. 16. The liquid ejection head according to any one of configurations 1 to 15.

[0145] [Method 17] A method for manufacturing a liquid ejection head including a nozzle forming member in which a plurality of nozzles for ejecting liquid are formed, and a convex portion that protrudes from a surface of the nozzle forming member in a direction in which the plurality of nozzles eject liquid, the method comprising: a forming step of forming a hole in the nozzle forming member; a coating step of coating the holes with a curable resin to form protrusions that protrude from the surface of the nozzle forming member; a curing step of curing the convex portion; A method for manufacturing a liquid ejection head, comprising:

[0146] [Method 18] In the forming step, the holes are formed by a photolithography technique. A method for manufacturing a liquid ejection head according to Method 17.

[0147] [Method 19] In the forming step, the holes are formed simultaneously with the plurality of nozzles. 19. A method for manufacturing a liquid ejection head according to Method 17 or 18.

[0148] [Method 20] the protrusions are made of a thermosetting resin, In the curing step, the convex portion is heated. 20. A method for manufacturing a liquid ejection head according to any one of Methods 17 to 19.

Claims

1. a nozzle forming member in which a nozzle for ejecting a liquid is formed; a protrusion that protrudes from a surface of the nozzle forming member in a direction in which the nozzle ejects liquid, a base end of the protrusion is embedded in the nozzle forming member; A liquid ejection head characterized by:

2. a depth to which the protrusion is embedded in the nozzle forming member is substantially equal to a thickness of the nozzle forming member; The liquid ejection head according to claim 1 .

3. The depth to which the protrusion is embedded in the nozzle forming member is approximately equal to the length of the nozzle. The liquid ejection head according to claim 1 .

4. The convex portion is made of a thermosetting resin. The liquid ejection head according to claim 1 .

5. The elastic modulus of the protrusions is 2 GPa or more. The liquid ejection head according to claim 1 .

6. an electrical connection for receiving electrical power to eject liquid from the nozzle; a sealing material that seals the electrical connection portion; Further provided with The convex portion and the sealing material are made of the same material. The liquid ejection head according to claim 1 .

7. When the liquid ejection head is viewed from the ejection direction, the convex portion is formed parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction. The liquid ejection head according to claim 1 .

8. When the liquid ejection head is viewed from the ejection direction, the convex portion is arranged in a dashed line parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction. The liquid ejection head according to claim 1 .

9. When the liquid ejection head is viewed from the ejection direction, the convex portions are formed in a dotted pattern along a nozzle row in which the plurality of nozzles are arranged in a first direction. The liquid ejection head according to claim 1 .

10. When the liquid ejection head is viewed from the ejection direction, the convex portion has a region formed parallel to a nozzle row in which the plurality of nozzles are arranged along a first direction, and a region extending in a second direction that is outside the nozzle row in the first direction and intersects the first direction on a plane. The liquid ejection head according to claim 1 .

11. When the liquid ejection head is viewed from the ejection direction, the convex portion is formed so as to surround the nozzle. The liquid ejection head according to claim 1 .

12. a cross-sectional shape of a region of the convex portion that protrudes beyond the nozzle forming member is substantially trapezoidal; The liquid ejection head according to claim 1 .

13. a groove is formed in the nozzle forming member on at least one side of a region in which the protrusion is buried; The liquid ejection head according to claim 1 .

14. The nozzle forming member has grooves formed on both sides of an area where the protrusions are embedded. The liquid ejection head according to claim 13.

15. a liquid-repellent film is formed on the surface of the nozzle forming member; The liquid ejection head according to claim 1 .

16. a substrate laminated on the nozzle forming member and provided with an energy generating element for ejecting liquid from the nozzle, The base end of the protrusion is in contact with the substrate. The liquid ejection head according to claim 1 .

17. A method for manufacturing a liquid ejection head comprising: a nozzle forming member having a plurality of nozzles formed therein for ejecting liquid; and a convex portion that protrudes from a surface of the nozzle forming member in a direction in which the plurality of nozzles eject liquid, the method comprising: a forming step of forming a hole in the nozzle forming member; a coating step of coating the holes with a curable resin to form protrusions that protrude from the surface of the nozzle forming member; a curing step of curing the convex portion; A method for manufacturing a liquid ejection head, comprising:

18. In the forming step, the holes are formed by a photolithography technique. The method for manufacturing a liquid ejection head according to claim 17.

19. In the forming step, the holes are formed simultaneously with the plurality of nozzles. The method for manufacturing a liquid ejection head according to claim 17.

20. the protrusion is made of a thermosetting resin, In the curing step, the convex portion is heated. The method for manufacturing a liquid ejection head according to claim 17.

Images