Liquid discharge head, liquid discharge device, and manufacturing method for liquid discharge head

Abstract

To provide a liquid discharge head configured so that reliability on a connection part between an element substrate and an electric wiring board can be improved.SOLUTION: A liquid discharge head, which discharges liquid, comprises an element substrate having a terminal and a wiring substrate including a wiring part contacted with and connected to the terminal. A second distance between an end part of the element substrate and the wiring part is larger than a first distance between a surface on which the terminal is arranged and a portion opposing to the terminal of the wiring part, in a direction perpendicular to the surface on which the terminal is arranged in the element substrate.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a liquid ejection head, a liquid ejection device, and a method for manufacturing a liquid ejection head, and more particularly to a technique for connecting a terminal on a substrate and a wiring portion of a wiring board. [Background technology]

[0002] As an example of this type of technology, Patent Document 1 describes a method for manufacturing a liquid ejection head, which includes a process for directly connecting an electrode terminal of an element substrate and a wiring portion of a wiring substrate (electrical wiring substrate). Specifically, the wiring portion of the electrical wiring substrate is brought close to the electrode terminal provided on the element substrate, and then the electrodes are abutted or metal-bonded, and then the electrode portion is protected by a resin layer such as a sealant. This improves the productivity of liquid ejection heads, without requiring operations such as wire placement during connection, as in wire bonding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-54066 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the process of connecting the wiring portion to the terminal of the substrate is performed in a state where the terminal and the wiring portion face each other. Therefore, for example, if the wiring substrate is tilted unintentionally, the wiring portion may come into contact with the element substrate in a region other than the region facing the terminal. As a result, there is a risk of causing problems such as poor electrical connection.

[0005] In view of the above, an object of the present disclosure is to provide a liquid ejection head capable of improving the reliability of the connection between an element substrate and an electric wiring substrate. [Means for solving the problem]

[0006] The liquid ejection head of the present disclosure comprises an element substrate having terminals, and a wiring substrate including a wiring portion connected to and in contact with the terminals, and is characterized in that a second distance between an end of the element substrate and the wiring portion is greater than a first distance, in a direction perpendicular to the surface of the element substrate on which the terminals are provided, between a surface on which the terminals are provided and a portion of the wiring portion facing the terminals. Effect of the Invention

[0007] According to the liquid ejection head of the present disclosure, it is possible to improve the reliability of the connection portion between the element substrate and the electric wiring substrate. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of a liquid ejection device according to an embodiment; [Diagram 2] FIG. 2 is a perspective view showing one of the head parts according to the embodiment. [Diagram 3] FIG. 2 is a perspective view illustrating a configuration of a liquid ejection unit according to the embodiment. [Figure 4] FIG. 2 is an exploded perspective view of the liquid ejection unit according to the embodiment. [Diagram 5] FIG. 2 is a diagram for explaining a configuration for connection according to an embodiment. [Figure 6] FIG. 2 is a cross-sectional view illustrating a liquid ejection unit according to an embodiment of the present invention. [Figure 7] 4A and 4B are diagrams illustrating the positional relationship between an element substrate and an electric wiring substrate according to an embodiment. [Figure 8] 5 is a flowchart showing a manufacturing process of the liquid ejection device according to the embodiment. [Figure 9] FIG. 2 is an explanatory diagram of a manufacturing process according to an embodiment. [Figure 10] FIG. [Figure 11] FIG. 2 is a cross-sectional view illustrating a liquid ejection unit according to an embodiment of the present invention. [Figure 12] FIG. 2 is a cross-sectional view illustrating a liquid ejection unit according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [First embodiment] FIG. 1 is a diagram showing a configuration of a liquid ejection device 100 according to an embodiment of the present disclosure.

[0010] First, the coordinate system shown in the figures referred to in this specification will be described. As shown in Fig. 1, the -Y direction is the direction in which the recording medium 101 is transported, and the +Y direction is the upstream side of the transport direction. The X direction is the longitudinal direction (width direction) of the liquid ejection head 103, and at this time, the lateral direction (depth direction) of the liquid ejection head 103 is the direction along the Y direction. The Z direction is the height direction of the liquid ejection head 103.

[0011] As shown in FIG. 1, a liquid ejection device 100 includes a transport unit 102 that transports a recording medium 101 in a transport direction, and a liquid ejection head 103 that ejects liquid onto the recording medium 101 .

[0012] In this embodiment, cut paper is used as the recording medium 101. The transport unit 102 has a transport belt, transport rollers for rotating the transport belt, and the like. In detail, the transport unit 102 transports the recording medium 101 by rotating the transport belt while adsorbing it to the transport belt using a suction mechanism (not shown). The recording medium 101 on which recording has been performed by the liquid ejection head is peeled off from the transport belt by a mechanism (not shown) downstream and ejected to a paper ejection unit (not shown). The liquid ejection head 103 is a so-called page-wide type liquid ejection head in which ejection openings are arranged in accordance with the width (length in the X direction) of the recording medium 101.

[0013] The liquid ejection head 103 is composed of liquid ejection heads 103C, 103M, 103Y, and 103K that eject cyan, magenta, yellow, and black liquids (e.g., inks) in order from the upstream side in the conveying direction of the recording medium. The liquid ejection head 103C that ejects cyan ink is composed of a head portion 103Ca and a head portion 103Cb joined together. Like the liquid ejection head 103C, the liquid ejection head 103M for magenta ink is composed of a head portion 103Ma and a head portion 103Mb joined together. Like the liquid ejection head 103M, the liquid ejection head 103Y for yellow ink is composed of a head portion 103Ya and a head portion 103Yb joined together. Like the liquid ejection head 103Y, the liquid ejection head 103K for black ink is composed of a head portion 103Ka and a head portion 103Kb joined together. Hereinafter, when there is no need to particularly distinguish between the head portions 103Ca, 103Cb, 103Ma, 103Mb, 103Ya, 103Yb, 103Ka, and 103Kb, they will simply be referred to as head portions.

[0014] The liquid ejection heads 103C, 103M, 103Y, and 103K each have the same configuration. The liquid ejection heads 103C, 103M, 103Y, and 103K are supplied with ink of a color corresponding thereto, thereby ejecting the ink of each color described above. Hereinafter, when there is no need to particularly distinguish between the liquid ejection heads 103C, 103M, 103Y, and 103K, they will simply be referred to as liquid ejection heads 103. In this embodiment, the liquid ejection head 103 ejects cyan, magenta, yellow, and black ink, thereby enabling full-color printing on the conveyed recording medium 101.

[0015] FIG. 2 is a perspective view showing one of the head parts in the liquid ejection head 103 according to the present embodiment described with reference to FIG.

[0016] 2, the head portion of the liquid ejection head 103 includes a liquid ejection unit 202 having a mechanism for ejecting liquid, and a common support member 203 that supports a plurality of liquid ejection units 202. The head portion of the liquid ejection head 103 also includes a reference member 201 that has a positioning function with respect to the liquid ejection device 100. The liquid ejection head 103 is positioned with respect to the liquid ejection device 100 by engaging this reference member 201 with an engagement portion (not shown) of the liquid ejection device 100.

[0017] In this embodiment, four liquid ejection units 202 are arranged in a staggered pattern on a common support member 203. Approximately 1000 ejection ports 204 are formed in each liquid ejection unit 202, and the liquid ejection unit 202 ejects liquid from the ejection ports 204, enabling recording at 1200 dpi.

[0018] FIG. 3 is a perspective view showing a detailed configuration of the liquid ejection unit 202 shown in FIG.

[0019] 3, the liquid ejection unit 202 includes an element substrate 301 including ejection ports for ejecting liquid, liquid flow paths communicating with the ejection ports, energy generating elements, etc., and an electric wiring substrate 302 electrically connected to the element substrate 301. Examples of the electric wiring substrate 302 include FPC (Flexible printed circuits) and TAB (Tape Automated Bonding).

[0020] The liquid ejection unit 202 includes a support member 303 for reinforcing the element substrate 301. The support member 303 is joined to the ejection surface side of the element substrate 301. The electric wiring substrate 302 is provided with a drive circuit substrate 304 for driving an energy generating element (not shown) that generates energy for ejecting liquid. In this embodiment, a piezoelectric element is used as the energy generating element.

[0021] FIG. 4 is an exploded perspective view of the liquid ejection unit 202 in this embodiment.

[0022] 4, a plurality of electrode terminals 401 are provided along the longitudinal direction at both ends of the element substrate 301. An electrical connection portion 402 is provided along the lateral direction at an end of the electrical wiring substrate 302. At the electrical connection portion 402, a conductor (e.g., a wiring containing copper and nickel) is exposed in a pad shape, and functions as a connection region with the electrode terminal 401. When the electrical connection portion 402 comes into contact with the electrode terminal 401, the element substrate 301 and the electrical wiring substrate 302 are electrically connected.

[0023] FIG. 5 is a diagram for explaining a configuration for connecting the element substrate 301 and the electric wiring substrate 302 in this embodiment.

[0024] 5, first alignment marks 501 are provided at both ends of element substrate 301 to serve as a reference for alignment when connecting electric wiring substrate 302. On the other hand, second alignment marks 502 are provided at the ends of electric wiring substrate 302 to serve as a reference for alignment with element substrate 301. By this alignment, electrical connection portion 402 of electric wiring substrate 302 can be aligned with element substrate 301 with high precision.

[0025] As described above, the element substrate 301 of this embodiment includes a piezoelectric element as an energy generating element for discharging liquid. The element substrate 301 that discharges liquid by a piezoelectric method tends to be provided with a relatively large number of electrode terminals 401. For this reason, in this embodiment, the distance between two adjacent electrode terminals is relatively narrow. Under such circumstances, in order to accurately connect the electrical connection portion 402 to the electrode terminal 401, it is preferable to align the first alignment mark 501 and the second alignment mark 502 with high accuracy.

[0026] FIG. 6 is a cross-sectional view that shows a schematic diagram of a liquid ejection unit 202 in this embodiment, and mainly shows the positional relationship between an electrical connection portion 402 of an electrical wiring board 302 and an electrode terminal 401 of an element substrate.

[0027] 6, the element substrate 301 includes a flow path forming substrate 601 having a flow path (not shown), an actuator substrate 602 having a surface on which electrode terminals 401 are provided, and a discharge port forming substrate 403 on which discharge ports 204 are formed. The actuator substrate 602 is layered on the discharge port forming substrate 403, and the flow path forming substrate 601 is layered on the actuator substrate 602.

[0028] The electric wiring board 302 includes a base portion 604 including polyimide, a wiring portion 605 including copper and nickel, and a cover portion 606 including a solder resist. The connection between the element substrate 301 and the electric wiring board 302 is maintained by a non-conductive resin (Non Conductive Paste) 607.

[0029] A sealant 608 is applied on the non-conductive resin 607. The sealant 608 preferably has a rigidity for protecting the connection between the element substrate 301 and the electric wiring substrate 302 from external forces, and is capable of suppressing corrosion caused by the liquid for ejection and moisture in the environment. A preferred example of the sealant 608 is epoxy resin. However, examples of the sealant 608 are not limited to epoxy resin. The sealant 608 can contain various materials according to the required performance.

[0030] 6, the electrical connection portion 402 of the electrical wiring board 302 has a connection range 402a that connects with the electrode terminals 401, and a non-connection range 402b that is adjacent to the connection range 402a and does not face the electrode terminals 401. Specifically, the connection range 402a faces the range in which the electrode terminals 401 on the actuator substrate 602 of the element substrate 301 are arranged, and is connected to these electrode terminals 401.

[0031] In this embodiment, the non-connected range 402b of the electrical connection portion 402 has an inclined portion 609 that is inclined in a direction (upward in FIG. 6) away from the actuator substrate 602. This inclined portion 609 is formed by being shaped in a manufacturing process that will be described later with reference to FIGS.

[0032] The angle of this inclined portion 609 is preferably 160 degrees or more with respect to a horizontal portion 610 of electrical connection portion 402 that is approximately parallel to the surface on which electrode terminal 401 is provided. This is because electric wiring board 302 has an elastic restoring force, and as the angle of inclined portion 609 becomes smaller, this elastic restoring force increases. In other words, if the angle of inclined portion 609 is too small, it becomes difficult to form and maintain inclined portion 609 by the above-mentioned forming.

[0033] Furthermore, as will be described in detail later in FIG. 7, the electrical connection portion 402 is configured so that the distance between the highest point of the slope of the non-connected area 402b and the actuator substrate 602 is greater than the distance between the connected area 402a and the actuator substrate 602.

[0034] By connecting the wiring portion 605 to the electrode terminal 401, it becomes possible to supply energy and an electric signal for ejecting liquid from the electric wiring board 302 to the element substrate 301. Then, the element substrate 301 is energized and communicates with the outside via the electric wiring board 302, and is able to eject liquid.

[0035] In this embodiment, the actuator substrate 602 of the element substrate 301 includes an energy generating element (piezo element, not shown) that is configured by an upper electrode film (not shown), a piezoelectric layer (not shown), and a lower electrode film (not shown). When the actuator substrate 602 receives a signal supplied from the wiring portion 605 via the electrode terminal 401, the actuator substrate 602 changes the volume of the piezo element and ejects a droplet from the ejection port 204.

[0036] In the piezoelectric element substrate 301, the number of flow paths is divided into individual flow paths equal to the number of ejection ports 204 that eject droplets, and a piezoelectric element that generates pressure for ejection is attached to each of the individual flow paths. If it is attempted to form ejection ports 204 at high density without changing the dimensions of the element substrate 301, it is necessary to increase the number of piezoelectric elements. As the number of piezoelectric elements increases, the number of electrode terminals 401 required also increases. As the number of electrode terminals 401 increases, the number of electrodes also increases accordingly.

[0037] As described above, according to the connection configuration of this embodiment, the non-connection area 402b adjacent to the connection area 402a of the electrical connection portion 402 of the electric wiring board 302 is inclined to move away from the actuator substrate 602 of the element substrate 301. Therefore, even if the electric wiring board 302 is unintentionally inclined while the wiring portion 605 is being brought closer to the actuator substrate 602, the non-connection area 402b is in a state of being separated from the actuator substrate 602 by the inclined portion 609 formed in advance. According to such a connection method, it is possible to prevent the wiring portion 605 from coming into contact with the actuator substrate 602 in the process of connecting the electric wiring board 302 to the element substrate 301.

[0038] Fig. 7 is a diagram for explaining the positional relationship in the connection between the element substrate 301 and the electric wiring substrate 302 described in Fig. 6. Note that Fig. 7 shows a connection step in the manufacturing process of the liquid ejection head, and at this stage, the non-conductive resin 607 and the sealing material 608 (see Fig. 6) shown in Fig. 6 have not been formed.

[0039] As shown in FIG. 7 , a second distance between the end of the element substrate 301 and the electrical wiring substrate 302 is greater than a first distance, in a direction perpendicular to the surface on which the electrode terminals 401 are provided, between the surface on which the electrode terminals 401 are provided and a portion facing the electrode terminals 401.

[0040] Specifically, in the direction perpendicular to the surface of the actuator substrate 602 on which the electrode terminals 401 are provided, a distance 701 from the surface to the connected area 402a is greater than a distance 702 from the edge of the surface to the non-connected area 402b.

[0041] As a result, even if the electric wiring board 302 is tilted unintentionally during the process of connecting the electric wiring board 302 to the element substrate 301, it is possible to prevent the wiring portion 605 from coming into contact with the actuator substrate 602.

[0042] Furthermore, by keeping the connection area 402a of the electrical wiring board 302 linear and tilting the non-connection area 402b, it is possible to properly ensure electrical connection while preventing unintended contact between the wiring portion 605 and the actuator board 602 described above.

[0043] The liquid ejection unit 202 of this embodiment manufactured by such a manufacturing method can suppress problems (such as current leakage and short circuits) caused by the wiring portion 605 coming into contact with the actuator substrate 602.

[0044] <Manufacturing Method of Liquid Ejector 100> 8 is a flowchart showing the manufacturing process of the liquid ejection device 100 in this embodiment. Note that the symbol "S" in the explanation of each process indicates the step (process) in the flowchart.

[0045] In S801, the element substrate 301 (not shown in FIG. 8) is set. After this step is completed, the step of S802 is carried out.

[0046] In S802, a non-conductive resin 607 (not shown in FIG. 8) is applied to the electrode terminals 401 (not shown in FIG. 8) of the element substrate 301 and the periphery of the electrode terminals 401. After this step is completed, the step of S803 is carried out.

[0047] Furthermore, before connecting the electric wiring board 302 (not shown in FIG. 8) to the element substrate 301, a hydrophilic treatment may be applied to the surface of the electric wiring board 302 facing the element substrate 301. The surface to which the hydrophilic treatment has been applied has improved wettability, making it easier for the non-conductive resin 607 to wet and spread, and it is possible to prevent the non-conductive resin 607 from dripping and flowing into the discharge port 204 (not shown in FIG. 8). Note that a treatment other than hydrophilic treatment may be applied to prevent the non-conductive resin 607 from dripping. Furthermore, the present invention is not limited to applying a hydrophilic treatment to the electric wiring board 302.

[0048] In S803, the element substrate 301 and the electric wiring substrate 302 are aligned. Before this step is performed, the electric wiring substrate 302 is held in a sucked state by a bending tool 900 (see FIG. 9(a)) described later. After this step is completed, the step of S804 is performed.

[0049] In S804, the electric wiring board 302 is brought close to the element substrate 301. Specifically, the electric wiring board 302 is brought close to the surface on which the electrode terminals 401 of the element substrate 301 are provided by the bending tool 900 while being kept substantially parallel to the surface. After this step is completed, the step of S805 is performed.

[0050] In S805, the electric wiring board 302 is connected to the element substrate 301. Specifically, in a state where the connection area 402a of the electric wiring board 302 is in contact with the electrode terminal 401 of the element substrate 301, the connection area 402a is heat-pressurized to the electrode terminal 401 from above the base portion 604 using a bending tool 900 (see FIG. 9(b)). After completion of this step, the step of S806 is performed.

[0051] In S806, the non-conductive resin 607 is cured. Specifically, temperature and time are applied to the non-conductive resin 607 according to the curing characteristics of the non-conductive resin 607 used. Then, a curing contraction force is generated, and the non-conductive resin 607 is cured. The non-conductive resin 607 is cured, thereby maintaining the connection between the element substrate 301 and the electric wiring substrate 302. After the completion of this step, the step of S807 is performed.

[0052] In S807, a sealant 608 is applied onto the non-conductive resin 607. Through this process, the liquid ejection unit 202 is completed. After this process is completed, the process of S808 is carried out.

[0053] In S808, the liquid ejection unit 202 is attached to the main body of the liquid ejection head 103 (not shown in FIG. 8). Through this process, the liquid ejection head 103 is completed. After this process is completed, the process of S809 is carried out.

[0054] In S809, the liquid ejection head 103 is attached to a predetermined position in the liquid ejection device 100 (not shown in FIG. 8). Through this process, the liquid ejection device 100 is completed.

[0055] The above is a description of the flowchart of the manufacturing process for the liquid ejection device 100.

[0056] FIG. 9( a ) is an explanatory diagram of a process of bringing the electric wiring board 302 close to the element substrate 301 .

[0057] 9(a), before the step of bringing the electric wiring board 302 closer to the element substrate 301 is performed, the electric wiring board 302 is held by a shaping tool 900. The shaping tool 900 has a pressing surface 901 capable of pressing and heating the electric wiring board 302, and an adsorption surface 902 capable of adsorbing and holding the electric wiring board 302. The adsorption surface 902 is provided with a suction portion 903 that sucks the electric wiring board 302. The adsorption surface 902 is located above the pressing surface 901 in the vertical direction.

[0058] Therefore, when electric wiring board 302 is sucked up by suction portion 903 while in contact with pressing surface 901, a part of electric wiring board 302 on the inside of the part in contact with pressing surface 901 adheres closely to adsorption surface 902. In other words, when electric wiring board 302 is sucked up by suction portion 903 while in contact with pressing surface 901, electric wiring board 302 is elastically deformed and inclined portion 609 is formed. However, when suction by suction portion 903 stops, electric wiring board 302 returns to its original shape due to an elastic restoring force.

[0059] FIG. 9B is an explanatory diagram of a process for connecting the electric wiring board 302 to the element substrate 301. As shown in FIG.

[0060] 9B, before the step of connecting the electric wiring board 302 to the element board 301 is performed, the non-conductive resin 607 is applied around the electrode terminal 401 of the actuator board 602. In a state in which the inclined portion 609 is formed by the bending tool 900, the non-conductive resin 607 is heated and, as time passes, the non-conductive resin 607 hardens and maintains the shape of the inclined portion 609. That is, even after the bending tool 900 is removed from the electric wiring board 302, the hardened non-conductive resin 607 supports the electric wiring board 302 and maintains the shape of the inclined portion 609. The temperature and time required to harden the non-conductive resin 607 depend on the material contained in the non-conductive resin 607.

[0061] <Contact Between Actuator Substrate 602 and Electrical Connection Part 402> A comparative example will be described below with respect to the contact between the actuator substrate 602 and the electrical connection portion 402. Descriptions of configurations similar to those of this embodiment will be omitted where appropriate, and differences from this embodiment will be mainly described.

[0062] FIG. 10A is a diagram showing a state in which an electric wiring board 302 is properly connected to an element substrate 301 in the comparative example.

[0063] 10(a), in the comparative example, a bonding tool 1000 is used for connecting an electric wiring board 302 to an element substrate 301. The bonding tool 1000 has also been used in the prior art. The bonding tool 1000 is capable of heat-pressure bonding the electric connection portion 402 of the electric wiring board 302 to the electrode terminal 401 of the element substrate 301, and is provided with a suction portion 1001 that sucks the electric wiring board 302. There is no height difference on the bottom surface of the bonding tool 1000, and even if the electric wiring board 302 is sucked by the suction portion 1001, the inclined portion 609 (see FIGS. 6 and 7) is not formed.

[0064] Regardless of the presence or absence of the inclined portion 609, as long as the electric wiring board 302 can be connected in parallel to the element substrate 301, the above-mentioned problems do not occur.

[0065] FIG. 10B is a diagram showing a state in which the electric wiring board 302 is not properly connected to the element board 301 in the comparative example.

[0066] 10(b), the electric wiring board 302 of the comparative example does not have the inclined portion 609. Therefore, for example, when the joining tool 1000 tilts while holding the electric wiring board 302, there is a risk that the electric connection portion 402 may come into contact with the actuator board 602. That is, in this comparative example, there is a risk that the above-mentioned problem may occur.

[0067] In contrast to this, in this embodiment, the electric wiring board 302 has an inclined portion 609 (see FIGS. 6 and 7), and a large clearance is ensured between the actuator substrate 602 and the wiring portion 605. Therefore, according to the technology of the present disclosure, even if the electric wiring board 302 is unintentionally inclined in the process of connecting the electric wiring board 302 to the element substrate 301, the electric connection portion 402 is prevented from coming into contact with the actuator substrate 602.

[0068] Therefore, according to the liquid ejection head 103 of this embodiment, the reliability of the connection between the element substrate 301 and the electric wiring substrate 302 can be improved.

[0069] [Second embodiment] In this embodiment, a recess is provided in the non-connected area to increase the clearance between the element substrate and the electrical wiring substrate. The following mainly describes the differences from the above-described embodiment. The same components as those in the above-described embodiment are given the same reference numerals, and duplicate descriptions of those components are omitted as appropriate.

[0070] FIG. 11A is a schematic cross-sectional view showing a process of connecting an electric wiring board 302 to an element substrate 301 in this embodiment.

[0071] 11(a), in the non-connected area 402b of this embodiment, a recess 1101 that is recessed in a direction away from the actuator substrate 602 is formed in the non-connected area 402b when the electric wiring substrate 302 is connected to the element substrate 301. When the electric wiring substrate 302 is connected to the element substrate 301, the recess 1101 is located above the edge of the actuator substrate 602 in the vertical direction.

[0072] In addition, in this embodiment, since the recess 1101 is formed, the clearance between the element substrate 301 and the electric wiring substrate 302 can be increased without forming an inclined portion. Therefore, the joining tool 1000 used in the conventional technology can be reused. According to such a connection method, it is not necessary to consider the relationship between the elastic restoring force of the electric wiring substrate 302 and the suction force of the suction portion 1001.

[0073] Therefore, according to the manufacturing method of this embodiment, the connection area 402a can be heat-pressurized to the electrode terminal 401 more easily than in the first embodiment.

[0074] FIG. 11(b) is a schematic cross-sectional view for explaining a recess 1101 in this embodiment.

[0075] As shown in FIG. 11(b), in a state in which the electric wiring board 302 is connected to the element substrate 301, the deepest part 402c of the recess 1101 is located above the edge of the actuator substrate 602 in the vertical direction.

[0076] Furthermore, in the electrical connection portion 402 of this embodiment, if the thickness of the connection range 402a is "F" and the thickness from the adhesive surface with the base portion 604 to the deepest part 402c of the recess 1101 is "F'", the following formula (1) is established.

[0077] Formula (1)...F>F'

[0078] With this configuration, the distance from the edge of the actuator substrate 602 to the deepest part 402c of the recess 1101 is greater than the distance from the surface of the actuator substrate 602 on which the electrode terminals 401 are provided to the underside of the connection range 402a.

[0079] Therefore, in the portion of the non-connection range 402b where the recess 1101 is provided, the wiring portion 605 can be separated from the actuator substrate 602 by the depth of the recess 1101. That is, in the process of connecting the electric wiring substrate 302 to the element substrate 301, the risk of the wiring portion 605 coming into contact with the actuator substrate 602 can be reduced.

[0080] FIG. 11C is a schematic cross-sectional view of a second liquid ejection unit 1100 in this embodiment.

[0081] 11(c), the non-conductive resin 607 flows into the recess 1101, so that the element substrate 301 and the electric wiring substrate 302 are connected more firmly than in the first embodiment. When the above-mentioned hydrophilic treatment is performed, it is preferable to perform the treatment on the recess 1101 as well. This is because the non-conductive resin 607 flows more easily into the recess 1101 than when the hydrophilic treatment is not performed.

[0082] Therefore, according to the second liquid ejection unit 1100, it is possible to improve the reliability of the connection between the element substrate 301 and the electric wiring substrate 302. Furthermore, it is also possible to connect the electric wiring substrate 302 to the element substrate 301 more easily than in the first embodiment.

[0083] [Third embodiment] In this embodiment, a step is provided on the edge of the actuator substrate to increase the clearance between the element substrate and the electrical wiring substrate. The following mainly describes the differences from the above-described embodiment. The same components as those in the above-described embodiment are given the same reference numerals, and duplicate descriptions of those components will be omitted as appropriate.

[0084] FIG. 12(a) is a schematic cross-sectional view showing a process of connecting an electrical connection portion 402 to an electrode terminal 401 in this embodiment.

[0085] 12(a), in a state in which the electric wiring board 302 is connected to the element substrate 301, a step 1201 is formed on the edge of the actuator substrate 602 in this embodiment, which step descends in a direction away from the electrical connection portion 402. In a state in which the electric wiring board 302 is connected to the element substrate 301, the step 1201 is located vertically below the non-connected range 402b.

[0086] FIG. 12B is a schematic cross-sectional view for explaining a step 1201 in this embodiment.

[0087] 12(b), in this embodiment, the distance from the bottom of the step 1201 to the underside of the non-connection area 402b is longer than the distance from the surface of the actuator substrate 602 on which the electrode terminals 401 are provided to the underside of the connection area 402a. With this configuration, the actuator substrate 602 can be separated from the electrical connection portion 402 by the amount of the drop in the step 1201.

[0088] Therefore, in the process of connecting the electrical connection portion 402 to the electrode terminal 401, the risk of the wiring portion 605 coming into contact with the actuator substrate 602 can be reduced.

[0089] FIG. 12C is a schematic cross-sectional view of a third liquid ejection unit 1200 in this embodiment.

[0090] 12(c), the non-conductive resin 607 accumulates in the step 1201, so that the element substrate 301 and the electric wiring substrate 302 are connected more firmly than in the first embodiment. When the above-mentioned hydrophilic treatment is applied to the wiring portion 605, the non-conductive resin 607 can be more effectively prevented from dripping from the step 1201 than when the hydrophilic treatment is not applied.

[0091] Therefore, according to the third liquid ejection unit 1200, it is possible to improve the reliability of the connection between the element substrate 301 and the electric wiring substrate 302. Furthermore, it is also possible to connect the electric wiring substrate 302 to the element substrate 301 more easily than in the first embodiment.

[0092] [Other embodiments] Although examples to which the technology of the present disclosure can be applied have been described above, the technical scope of the present disclosure is not limited to the above examples. The first, second, and third embodiments may be combined as appropriate.

[0093] In the above embodiment, the manufacturing process of the liquid ejection device has been described, but the order of performing each step is not limited as long as the liquid ejection device can be manufactured. The order of each step in the manufacturing process of the liquid ejection device may be changed as appropriate, or the steps may be performed simultaneously.

[0094] In the above embodiment, the liquid is ink, but the liquid to which the technology of the present disclosure can be applied is not limited to ink. In other words, various recording liquids including treatment liquids used for the purposes of improving the fixation of ink on a recording medium, reducing uneven gloss, and improving abrasion resistance may be used.

[0095] In the above embodiment, the recording medium is described assuming that it is cut paper, but the recording medium is not limited to cut paper as long as it is capable of applying liquid. Other examples of recording media include continuous roll paper, plastic, film, textile, metal, and flexible substrates.

[0096] In the above embodiment, the electrode terminals are provided along both sides of the element substrate, but the electrode terminals may be provided along all sides of the element substrate. In this case, the electrical wiring board is drawn out from all ends of the element substrate. Therefore, compared to the above embodiment, the number of electrodes can be increased, and the density of the multiple ejection ports formed can be increased. By increasing the density of the ejection ports, it becomes possible to maintain high recording quality even during high-speed recording.

[0097] In the above embodiment, the energy generating means is described assuming a piezoelectric element, but the example of the energy generating means is not limited to a piezoelectric element as long as it can impart the energy required for ejection to the liquid. Another example of the energy generating means is an electrothermal converter. For example, a heater as an electrothermal converter may be used to apply heat to the liquid to generate bubbles, thereby ejecting the liquid from the ejection port. The technology disclosed herein can also be applied to such so-called thermal type liquid ejection units.

[0098] In the above embodiment, a so-called page-wide type liquid ejection head is used, but the technology disclosed herein can also be applied to a liquid ejection head that performs printing while scanning, i.e., a so-called serial type liquid ejection head.

[0099] In the above embodiment, multiple liquid ejection units were arranged on one support member, but the technology disclosed herein can also be suitably used in a liquid ejection head in which one liquid ejection unit is arranged on one support member.

[0100] In the above embodiment, the non-conductive resin is applied to the element substrate, but an electrical wiring substrate to which a non-conductive resin is applied may be connected to an element substrate to which a non-conductive resin is not applied. In other words, whether the non-conductive resin is applied to the element substrate or the electrical wiring substrate can be appropriately selected depending on the configuration of the liquid ejection device.

[0101] In the above embodiment, the element substrate and the electric wiring substrate are connected by a non-conductive resin, but the element substrate and the electric wiring substrate may be connected by an anisotropic conductive resin film (ACF: Anisotropic Conductive Film). Also, it is possible to connect the element substrate and the electric wiring substrate by a method such as a metal bonding method using ultrasonic waves, heat, etc., using gold bumps formed on the electrodes.

[0102] In the step of connecting the electric wiring board to the element substrate in the first, second, and third embodiments, the electric wiring board is brought closer to the element substrate in a substantially parallel (horizontal) state with the distance between the element substrate and the electric wiring board increased. However, the technology disclosed in the present disclosure can be applied to the manufacturing method to suppress unintended contact between the element substrate and the electric wiring board. That is, when the electric wiring board is brought closer to the element substrate in the connection step, the entire electric wiring board may be tilted so that the distance from the element substrate increases as the electric wiring board becomes farther from the electrode terminal. According to this manufacturing method, it is possible to suppress contact between the element substrate and the electric wiring board, as in the above-mentioned embodiment. Then, for example, the electric wiring board may be returned to the normal state, and the electrode terminal of the element substrate and the electrolytic wiring board may be connected by applying a pressing force, and then the subsequent step may be performed.

[0103] In the above embodiment, the description is based on the assumption that the electrode terminals are connected to wiring. However, the technology disclosed herein is not limited to the connection between the electrode terminals and wiring, and can be widely applied to technologies for connecting terminals.

[0104] The present disclosure includes the following configurations and methods.

[0105] [Configuration 1] A liquid ejection head, An element substrate having a terminal; a wiring board including a wiring portion connected to the terminal in contact therewith; Equipped with a second distance between an end of the element substrate and the wiring portion is larger than a first distance between a surface of the element substrate on which the terminals are provided and a portion of the wiring portion facing the terminals, in a direction perpendicular to the surface of the element substrate on which the terminals are provided; A liquid ejection head comprising:

[0106] [Configuration 2] the wiring board has an inclined portion inclined in a direction away from a surface of the element substrate on which the terminals are provided, A liquid ejection head according to configuration 1.

[0107] [Configuration 3] The angle of the inclined portion is 160 degrees or more with respect to the horizontal portion of the wiring portion. 3. The liquid ejection head according to configuration 2.

[0108] [Configuration 4] the wiring portion has a recess that is recessed in a direction away from a surface of the element substrate on which the terminals are provided, 4. The liquid ejection head according to any one of configurations 1 to 3.

[0109] [Configuration 5] the element substrate has a step that is spaced apart from the wiring portion from a surface on which the terminals are provided, 5. The liquid ejection head according to any one of configurations 1 to 4.

[0110] [Configuration 6] a non-conductive resin applied between the element substrate and the wiring portion, The connection between the wiring portion and the terminal is maintained by the non-conductive resin. 6. The liquid ejection head according to any one of configurations 1 to 5.

[0111] [Configuration 7] the element substrate has an ejection port for ejecting liquid, and an element for generating energy for ejecting the liquid from the ejection port; The liquid ejection head according to any one of configurations 1 to 6.

[0112] [Configuration 8] The element is a piezoelectric element. A liquid ejection head according to configuration 7.

[0113] [Configuration 9] A liquid ejection head according to any one of configurations 1 to 8, A liquid ejection device comprising:

[0114] [Method 10] A method for manufacturing a liquid ejection head including an element substrate having terminals and a wiring substrate including a wiring portion connected to the terminals by contact therewith, a coating step of coating a non-conductive resin that maintains the connection between the terminal and the wiring portion; a connecting step of connecting the terminal and the wiring portion; Including, In the connecting step, the wiring portion is connected to the terminal in a state in which a second distance between an end portion of the element substrate and the wiring portion is larger than a first distance between a surface of the element substrate on which the terminal is provided and a portion of the wiring portion facing the terminal, in a direction perpendicular to the surface of the element substrate on which the terminal is provided. A method for manufacturing a liquid ejection head comprising the steps of:

[0115] [Method 11] In the connecting step, the terminal and the wiring portion are crimped together by a tool for holding the wiring board. A method for manufacturing a liquid ejection head according to method 10.

[0116] [Method 12] the tool has a pressing surface that presses the wiring board, and a suction surface that is located vertically above the pressing surface and that suctions the wiring board; In the connecting step, a part of the wiring board is pressed against the pressing surface, and a part of the wiring board that is not pressed against the pressing surface is sucked up by the suction surface, thereby forming an inclined portion on the wiring board that is inclined away from the terminal. A method for producing a liquid ejection head according to the method 11.

[0117] [Method 13] In the connecting step, the non-conductive resin is hardened to maintain the shape of the inclined portion. A method for producing a liquid ejection head according to method 12.

Claims

1. A liquid ejection head, An element substrate having a terminal; a wiring board including a wiring portion connected to the terminal in contact therewith; Equipped with a second distance between an end of the element substrate and the wiring portion is larger than a first distance between a surface of the element substrate on which the terminals are provided and a portion of the wiring portion facing the terminals, in a direction perpendicular to the surface of the element substrate on which the terminals are provided; A liquid ejection head comprising:

2. the wiring board has an inclined portion inclined in a direction away from a surface of the element substrate on which the terminals are provided, The liquid ejection head according to claim 1 .

3. The angle of the inclined portion is 160 degrees or more with respect to the horizontal portion of the wiring portion. The liquid ejection head according to claim 2 .

4. the wiring portion has a recess that is recessed in a direction away from a surface of the element substrate on which the terminals are provided, The liquid ejection head according to claim 1 .

5. the element substrate has a step that is spaced apart from the wiring portion from a surface on which the terminals are provided, The liquid ejection head according to claim 1 .

6. a non-conductive resin applied between the element substrate and the wiring portion, The connection between the wiring portion and the terminal is maintained by the non-conductive resin. The liquid ejection head according to claim 1 .

7. the element substrate has an ejection port for ejecting liquid, and an element for generating energy for ejecting the liquid from the ejection port; The liquid ejection head according to claim 1 .

8. The element is a piezoelectric element.

8. A liquid ejection head according to claim 7.

9. A liquid ejection head comprising: A liquid ejection device comprising:

10. A method for manufacturing a liquid ejection head including an element substrate having terminals and a wiring substrate including a wiring portion connected to the terminals by contact therewith, a coating step of coating a non-conductive resin that maintains the connection between the terminal and the wiring portion; a connecting step of connecting the terminal and the wiring portion; Including, In the connecting step, the wiring portion is connected to the terminal in a state in which a second distance between an end portion of the element substrate and the wiring portion is larger than a first distance between a surface of the element substrate on which the terminal is provided and a portion of the wiring portion facing the terminal, in a direction perpendicular to the surface of the element substrate on which the terminal is provided. A method for manufacturing a liquid ejection head comprising the steps of:

11. In the connecting step, the terminal and the wiring portion are crimped together by a tool for holding the wiring board. The method for manufacturing a liquid ejection head according to claim 10.

12. the tool has a pressing surface that presses the wiring board, and a suction surface that is located vertically above the pressing surface and that suctions the wiring board; In the connecting step, a part of the wiring board is pressed against the pressing surface, and a part of the wiring board that is not pressed against the pressing surface is sucked up by the suction surface, thereby forming an inclined portion on the wiring board that is inclined away from the terminal. The method for manufacturing a liquid ejection head according to claim 11.

13. In the connecting step, the non-conductive resin is hardened to maintain the shape of the inclined portion. The method for manufacturing a liquid ejection head according to claim 12.

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