Liquid discharge head, liquid discharge device, and discharge module

Abstract

To provide a liquid discharge head which is small-sized and has the high reliability of an electrical connection part.SOLUTION: A liquid discharge head comprises: a plurality of element substrates on which a plurality of discharge elements discharging the same type of liquid are arranged; and a plurality of electrical wiring members which supply power to the plurality of respective element substrates. The plurality of element substrates are arrayed along a prescribed direction having an inclination with respect to the array direction in which the plurality of discharge elements are arrayed. Each of the plurality of electrical wiring members is arranged on an end in the direction in which the plurality of discharge elements on the element substrate are arrayed and extends in the same direction intersecting the prescribed direction from each of the plurality of element substrates.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a liquid ejection head, a liquid ejection device, and an ejection module. [Background technology]

[0002] In general, it is desirable to reduce the manufacturing cost of a liquid ejection head. In order to reduce the manufacturing cost of a liquid ejection head, attempts have been made to miniaturize the liquid ejection head by miniaturizing the element substrate. On the other hand, further miniaturization of the element substrate reduces the bonding area between the element substrate and the flow path member that supplies liquid to the element substrate, lowering the reliability of the bonding.

[0003] To ensure reliability of adhesion, the print head assembly (i.e., liquid ejection head) of Patent Document 1 has rectangular print chips (i.e., "element substrates") arranged in-line to ensure a sufficient adhesion area. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent Application Publication No. 2005 / 0162468 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the print head assembly disclosed in Patent Document 1, a single print chip is used to eject multiple types of liquid, which may result in unevenness. Furthermore, the print chip disclosed in Patent Document 1 and the printed circuit board are electrically connected by a TAB film that is connected over almost the entire area of ​​the long side of the print chip. As a result, in order to seal this electrical connection, a sealing region that seals almost the entire area of ​​the long side of the print chip is required, making it difficult to miniaturize the element substrate.

[0006] SUMMARY OF THE DISCLOSURE In view of the above, an object of the present disclosure is to provide a liquid ejection head that is small in size and has highly reliable electrical connections. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the liquid ejection head disclosed herein is a liquid ejection head having a plurality of element substrates on which a plurality of ejection elements that eject the same type of liquid are arranged, and a plurality of electrical wiring members for supplying power to each of the plurality of element substrates, wherein the plurality of element substrates are arranged along a predetermined direction that is inclined with respect to the arrangement direction in which the plurality of ejection elements are arranged, and each of the plurality of electrical wiring members is arranged at an end of the element substrate in the direction in which the plurality of ejection elements are arranged, and extends from each of the plurality of element substrates in the same direction that intersects the predetermined direction. Effect of the Invention

[0008] According to the technique of the present disclosure, it is possible to provide a liquid ejection head that is small in size and has highly reliable electrical connections. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a liquid ejection device according to an embodiment. [Diagram 2] FIG. 1 is a perspective view showing a schematic example of a liquid ejection head according to an embodiment. [Diagram 3] FIG. 2 is a schematic top view of a liquid ejection head according to an embodiment. [Figure 4] 10A to 10C are diagrams illustrating the effect of reliability of electrical connection between an element substrate and an electrical wiring member in an embodiment. [Diagram 5] 11A and 11B are diagrams illustrating the effect of reliability of electrical connection between an element substrate and an electrical wiring member in a comparative example. [Figure 6] 11A and 11B are diagrams illustrating the effect of reliability of electrical connection between an element substrate and an electrical wiring member in a comparative example. [Figure 7]5A to 5C are diagrams illustrating the effect of suppressing unevenness in a liquid ejection head according to an embodiment. [Figure 8] 13 is a diagram showing the effect of suppressing unevenness in one comparative example. [Figure 9] 13 is a diagram showing the effect of suppressing unevenness in one comparative example. [Figure 10] FIG. 13 is a diagram for explaining an application example of an embodiment. [Figure 11] FIG. 13 is a diagram for explaining a comparative example. [Figure 12] FIG. 1 is a perspective view showing a schematic cross section of a liquid ejection head according to an embodiment. [Figure 13] FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG. [Figure 14] FIG. 13 is a diagram for explaining a comparative example. [Figure 15] FIG. 1 is a perspective view showing a schematic example of a liquid ejection head according to an embodiment. [Figure 16] FIG. 2 is a schematic top view of a liquid ejection head according to an embodiment. [Figure 17] FIG. 1 is a perspective view showing a schematic cross section of a liquid ejection head according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A liquid ejection head and a liquid ejection device according to an embodiment of the present invention will be described below with reference to the drawings. In each of the following embodiments, an inkjet recording head and an inkjet recording device that ejects ink will be described in a specific configuration, but the present invention is not limited thereto. The liquid ejection head, liquid ejection device, and liquid supply method of the present invention are applicable to devices such as printers, copiers, facsimiles with communication systems, and word processors with printer units, as well as industrial recording devices that are combined with various processing devices. For example, they can also be used for applications such as biochip production and electronic circuit printing.

[0011] In addition, the embodiments described below are appropriate specific examples of the present invention, and therefore various technically preferable limitations are attached to the embodiments, but as long as they are in line with the concept of the present invention, the present embodiments are not limited to the embodiments in the specification or other specific methods.

[0012] [First embodiment] <Liquid discharge device 10> FIG. 1 is a schematic diagram of a liquid ejection device 10 according to the present embodiment.

[0013] In this embodiment, the longitudinal direction of the recording unit 12 is defined as the ±X direction. The lateral direction of the recording unit 12 is defined as the ±Y direction. The recording medium P is transported in the +Y direction, which is appropriately referred to as the "transport direction." The direction of gravity (downward) is defined as the +Z direction, and the antigravity direction (upward) is defined as the -Z direction.

[0014] As shown in FIG. 1(a), the liquid ejection device 10 includes a conveying means 11 and a recording unit 12. The conveying means 11 conveys a sheet-shaped recording medium P in a predetermined direction (in the present embodiment, the +Y direction). As a result, the recording medium P passes under the recording unit 12 (the +Z direction side) in the predetermined direction at a predetermined speed. The recording unit 12 is mainly composed of a liquid ejection head 100, which will be described later. The liquid ejection head 100 is also composed of a plurality of ejection modules. The ejection module includes an element substrate having an ejection element array in which a plurality of ejection elements that eject the same type of liquid are arranged, and an electrical connection portion arranged at an end of the ejection element array in the arrangement direction. Furthermore, the ejection module includes an electrical connection member that is electrically connected to the electrical connection portion and extends in a direction intersecting the arrangement direction of the ejection element array. In this case, the ejection port in the ejection element array and the energy generating element for receiving electrical energy sent via the electrical connection member and ejecting liquid from the ejection port are collectively referred to as the "ejection element".

[0015] The liquid ejection head 100 includes a plurality of ejection ports 201 (see FIG. 3) that eject liquid (e.g., ink containing coloring material) as droplets. The plurality of ejection ports 201 are arranged in a range corresponding to the width (length in the X direction) of the recording medium P along a direction (X direction) that intersects (orthogonal in this embodiment) with the conveying direction (+Y direction) of the recording medium P. When the recording medium P passes under the liquid ejection head 100, ejection elements provided corresponding to each ejection port of the liquid ejection head 100 are driven according to ejection data. As a result, liquid is ejected from the ejection ports 201 toward the recording medium P in the +Z direction, and an image is recorded. In this way, the liquid ejection device 10 in this embodiment is a full-line type recording device that ejects liquid from the ejection element array 202 (see FIG. 3) arranged along the width direction (X direction) of the recording medium P while conveying the recording medium P continuously or intermittently, thereby performing recording.

[0016] FIG. 1B is a block diagram showing a control configuration of the liquid ejection device 10 in this embodiment. The liquid ejection device 10 includes a CPU 20, a ROM 21, and a RAM 22. The CPU 20 uses the RAM 22 as a work area according to a program stored in the ROM 21 and controls each part of the liquid ejection device 10 in an integrated manner. For example, the CPU 20 performs a predetermined image processing on image data received from an externally connected host device 30 according to a program and parameters stored in the ROM 21, and generates ejection data for driving the ejection elements of the liquid ejection head 100. The CPU 20 drives the liquid ejection head 100 according to the ejection data, and ejects liquid at a predetermined frequency. The CPU 20 also drives the conveying motor 23, and causes the conveying means 11 to convey the recording medium P in the +Y direction at a speed corresponding to the ejection frequency of the ejection operation by the liquid ejection head 100. As a result, an image corresponding to the image data received from the host device 30 is recorded on the recording medium P.

[0017] The liquid sending unit 24 is a unit for supplying liquid to the liquid ejection head 100. The liquid sending unit 24 controls a pressure control unit and a switching mechanism provided therein under the management of the CPU 20, and controls the flow of liquid in a liquid flow path including the liquid ejection head 100. The liquid sending unit 24 may function as a liquid supply unit that supplies liquid to the liquid ejection head 100, or may function as a liquid circulation unit that circulates liquid in a circulation path including the liquid ejection head 100.

[0018] <Description of Liquid Ejection Head 100> FIG. 2 is a perspective view that diagrammatically illustrates an example of the liquid ejection head 100 according to the present embodiment.

[0019] 2, the liquid ejection head 100 in this embodiment includes a first flow path member 101, a second flow path member 102, an element substrate 104, and an electric wiring member 105. The liquid ejection head 100 is configured by laminating the first flow path member 101 and the second flow path member 102 to which the element substrate 104 to which the electric wiring member 105 is electrically connected is attached. The first flow path member 101 and the second flow path member 102 are members that distribute liquid supplied from a liquid sending unit 24 (see FIG. 1(b)) of the liquid ejection device 10 to each element substrate 104. In other words, it can be said that the liquid ejection head 100 has a flow path portion in which a supply flow path that supplies liquid to the element substrate 104 is formed.

[0020] Inside the first flow path member 101, a flow path extending in the X direction and a flow path communicating with the second flow path member 102 in a state where the second flow path member 102 is stacked on the first flow path member 101 are formed. In the second flow path member 102, a flow path communicating with the first flow path member 101 is formed in a state where the second flow path member 102 is stacked on the first flow path member 101. Furthermore, in the second flow path member 102, a flow path communicating with the second flow path member 102 is formed in a state where the element substrate 104 is attached to the second flow path member 102. Inside the first flow path member 101, a flow path extending in the X direction is formed. By stacking the first flow path member 101, the second flow path member 102, and the element substrate 104 in this order, a flow path communicating from the flow path of the first flow path member 101 to each recording element of the element substrate 104 is formed.

[0021] On the upper surface of the second flow path member 102, 15 element substrates 104 are arranged (disposed in-line) in a substantially straight line in a direction intersecting the transport direction. In this embodiment, an electric wiring member 105 electrically connected to the element substrate 104 extends to the outside of the long side of the liquid ejection head 100 in the short direction of the liquid ejection head 100 (here, the -Y direction). An example of the electric wiring member 105 is a flexible wiring board. For example, by using four liquid ejection heads 100 configured in this manner and configuring each liquid ejection head 100 to eject ink of a different color, it is possible to eject ink of four colors, YMCK (yellow, magenta, cyan, black).

[0022] FIG. 3 is a schematic top view of the liquid ejection head 100 in this embodiment.

[0023] As shown in FIG. 3, the liquid ejection head 100 has a plurality of element substrates 104 on which a plurality of ejection elements that eject the same type of liquid are arranged, and a plurality of electrical wiring members 105 for supplying power to each of the plurality of element substrates.

[0024] The element substrates 104 are arranged along a predetermined direction (for example, the X direction in the figure) that is inclined with respect to the arrangement direction of the ejection elements. Each of the electric wiring members 105 is arranged at an end of the element substrate 104 in the direction in which the ejection elements are arranged, and extends from each of the element substrates 104 in the same direction (for example, the -Y direction in the figure) that intersects with the predetermined direction. In this embodiment, the shape of the element substrate 104 is substantially rectangular. The shape of the element substrate 104 may be substantially parallelogram. However, considering the substrate cutting process included in the manufacturing process of the element substrate 104, the shape of the element substrate 104 is preferably substantially rectangular rather than substantially parallelogram. An ejection port 201 for ejecting liquid is formed on the upper surface of the element substrate 104. Hereinafter, the surface of the element substrate 104 on the side on which the ejection port 201 is formed will be referred to as the "ejection surface" as appropriate. An ejection element array 202 in which a plurality of ejection ports 201 are arranged is disposed so as to be inclined at a certain angle with respect to the longitudinal direction (that is, the X direction) of the liquid ejection head 100. Hereinafter, the direction in which the ejection elements are arranged is referred to as the "arrangement direction."

[0025] Further, the multiple element substrates 104 are arranged so that two adjacent element substrates 104 have an overlapping region when viewed in a direction intersecting a predetermined direction (for example, the Y direction side). For example, the outlets 201 of one element substrate 104 of two adjacent element substrates 104 and the outlets 201 of the element substrate 104 adjacent to that element substrate 104 are arranged so as to overlap on the same axis in a direction intersecting the arrangement direction (Y direction).

[0026] Hereinafter, a region in the arrangement direction where the ejection element arrays of two adjacent element substrates among the plurality of element substrates overlap on the same axis in a direction intersecting the ejection element array direction (for example, the Y direction) will be referred to as a "connecting portion." On the other hand, a region in the X direction where the ejection element arrays of two adjacent element substrates do not overlap on the same axis in the Y direction will be referred to as a "non-connecting portion."

[0027] Further, an electrical connection portion 204 is provided at the further tip side in the arrangement direction (+X direction side). That is, the electrical connection portion 204 is provided at the further tip side in the arrangement direction than the ejection port arranged at the end of the arrangement direction in which the multiple ejection ports are arranged. The electrical connection portion 204 has a plurality of terminals arranged along the arrangement direction. Each terminal is electrically connected to the liquid ejection device 10 main body via the electrical wiring member 105. Note that each terminal may be arranged along the X direction as long as it can be electrically connected to the electrical wiring member 105. The electrical wiring member 105 is electrically connected to the electrical connection portion 204 of each element substrate 104 and extends in a direction intersecting the arrangement direction. Each element substrate 104 is electrically connected to an electrical wiring board (not shown) included in the recording unit 12 via the electrical wiring member 105.

[0028] FIG. 4 is a diagram for explaining the effect of the reliability of the electrical connection between the element substrate 104 and the electrical wiring member 105 in this embodiment.

[0029] As shown in FIG. 4, each electrical wiring member 105 extends from a terminal arranged on each electrical connection portion 204 provided on the ejection surface of each element substrate 104 toward the short side of the liquid ejection head 100 (in the illustrated example, the -Y direction) to the outside of the long side of the liquid ejection head 100.

[0030] Here, in order to realize a highly reliable electrical connection, it is preferable to prevent electrical interference by arranging the electrical connection portion 204 at a certain distance from the ejection element array 202 in the arrangement direction of the ejection elements. With this configuration, even if the distance 301 from the ejection element array 202 to the electrical connection portion between the element substrate 104 and the electrical wiring member 105 is increased, the effect on the area of ​​the element substrate 104 can be reduced compared to the comparative example described later.

[0031] <Comparative Example> In order to facilitate understanding of the electrical connections in this embodiment, two comparative examples that do not satisfy the requirements of the present invention will be described below. Note that descriptions of configurations that are the same as or correspond to those in this embodiment will be omitted as appropriate, and differences will be mainly described.

[0032] FIG. 5 is a diagram showing an example in which the electrical connection portions are not disposed at the ends in the arrangement direction.

[0033] 5, the shape of the element substrate 401 in this comparative example is substantially a parallelogram, which is different from the present embodiment. In this comparative example, the substantially parallelogram element substrate 401 is arranged in the X direction, so that the arrangement direction is tilted with respect to the X direction.

[0034] Also, the position where the electrical connection portion 402 is provided at approximately the center in the longitudinal direction of the element substrate 401 is different from that of the present embodiment. Therefore, the electrical wiring member 403 is also attached to approximately the center in the longitudinal direction of the element substrate 401.

[0035] In such a configuration, in order to ensure the distance 405 from the ejection element array 404 to the electrical connection portion 402, the length of the element substrate 401 in the short direction (Y direction) must also be increased. In other words, the area of ​​the element substrate 401 in the comparative example is larger than the area of ​​the element substrate 104 (see FIG. 4) in this embodiment. Therefore, in the configuration of this comparative example, it is more difficult to achieve both a small element substrate and reliable electrical connection compared to this embodiment.

[0036] FIG. 6 is a diagram showing an example in which the element substrate is arranged without tilting the arrangement direction.

[0037] As shown in FIG. 6, the difference from the present embodiment is that the ejection ports are arranged without being inclined with respect to the longitudinal direction of each element substrate 501. When the electrical wiring members 502 are extended in a direction intersecting the arrangement direction in a state in which the ejection ports are arranged without being inclined with respect to the longitudinal direction of each element substrate 501, it is necessary to arrange the element substrates 501 in a staggered manner in order to secure an area for providing a connecting portion. When arranging the element substrates 501 in a staggered manner, if all of the electrical wiring members 502 are extended in the same direction (for example, the -Y direction), the electrical wiring members of one of the two adjacent element substrates will interfere with the other element substrate. For example, if the orientation of the second element substrate from the left in the figure is reversed, the electrical wiring members 502 of that element substrate will physically collide with the third element substrate from the left in the figure.

[0038] To avoid such a situation, the element substrates 501 must be arranged so that the electrical wiring members 502 of each element substrate 501 extend alternately in opposite directions (+Y direction and -Y direction). This requires the addition of an electrical wiring substrate (not shown) that electrically connects to the electrical wiring members 502 not only on the -Y direction side but also on the +Y direction side, which increases manufacturing costs. This concludes the description of the electrical connections in the comparative example. Below, we return to the description of this embodiment.

[0039] <Suppression of unevenness> 7 is a diagram for explaining the effect of the liquid ejection head in this embodiment in suppressing unevenness. Here, for convenience of explanation, the description will be given in a state where the electric wiring member is removed from the element substrate. In addition, among the multiple liquid ejection heads 100 shown in FIG. 2, the liquid ejection head that ejects magenta ink will be referred to as the first liquid ejection head 100m, and the liquid ejection head that ejects cyan ink will be referred to as the second liquid ejection head 100c. In addition, the element substrate adjacent to the first element substrate 611 of the first liquid ejection head 100m will be referred to as the second element substrate 612. In addition, the element substrate adjacent to the third element substrate 613 of the second liquid ejection head 100c will be referred to as the fourth element substrate 614.

[0040] 7, the ejection element arrays on two adjacent element substrates are configured so that at least one ejection port overlaps with another in the conveying direction (Y direction) of the recording medium. For example, the illustrated "area 601" and "area 602" are "non-connecting portions," and "area 603" is a "connecting portion."

[0041] In the figure, "D1" indicates the distance between two ejection element arrays that eject ink of different colors in a "non-seam portion." For example, the distance in the transport direction from the ejection element array of the first element substrate 611 to the ejection element array of the third element substrate 613 in a "non-seam portion" region 601 is "D1." Similarly, the distance in the transport direction from the ejection element array of the second element substrate 612 to the ejection element array of the fourth element substrate 614 in a "non-seam portion" region 602 is also "D1."

[0042] On the other hand, "D2" indicates the maximum distance between two ejection element arrays that eject ink of different colors in the "connecting portion". For example, the distance in the transport direction from the ejection element array of the second element substrate 612 to the ejection element array of the third element substrate 613 in the region 603 that is the "connecting portion" is "D2". And the distance in the transport direction between two adjacent ejection element arrays that eject ink of the same color in the "connecting portion" is "ΔD". For example, in the "connecting portion" 603, the distance in the transport direction from the ejection element array of the third element substrate 613 to the ejection element array of the fourth element substrate 614, both of which eject cyan ink, is "ΔD".

[0043] As shown in FIG. 7, the multiple element substrates 104 are configured to include areas where the ejection element arrays of two adjacent element substrates 104 overlap with each other in a direction (e.g., the Y direction in the figure) that intersects a predetermined direction (e.g., the X direction in the figure).

[0044] Specifically, the first liquid ejection head 100m and the second liquid ejection head 100c are disposed in the transport direction (i.e., the Y direction). The first element substrate 611 and the second element substrate 612 of the first liquid ejection head 100m are disposed so as to be inclined at a certain angle with respect to the longitudinal direction (i.e., the X direction) of the first liquid ejection head 100m. Similarly, the third element substrate 613 and the fourth element substrate 614 of the second liquid ejection head 100c are disposed so as to be inclined at a certain angle with respect to the longitudinal direction (i.e., the X direction) of the second liquid ejection head 100c.

[0045] In general, the distance between the "non-connecting portions" of two liquid ejection heads that eject inks of different colors (i.e., distance "D1") tends to be large. On the other hand, in the "connecting portion," the distance from the ejection element array of an element substrate to the ejection element array of an element substrate adjacent to the element substrate (i.e., distance "ΔD") tends to be small compared to the distance between the "non-connecting portions" (i.e., distance "D1").

[0046] Therefore, in this embodiment, it can be said that the following two equations hold true. Formula (1)...ΔD≪D1 Formula (2)...D2=D1+ΔD

[0047] Here, taking into consideration "Equation (1)" and "Equation (2)", the distance in the transport direction between the ejection element rows that eject ink of different colors in the "connection portion" (i.e., "D2") can be expressed using the following equation: Formula (3)...D2≒D1

[0048] In other words, the distance between two adjacent ejection element rows that eject ink of different colors (corresponding to D2 and D1, respectively) is approximately the same in both the "joining portion" and the "non-joining portion." In other words, the time from when cyan ink is applied to when magenta ink is applied to a recording medium transported at a constant speed in the +Y direction does not differ significantly between the "joining portion" and the "non-joining portion."

[0049] Therefore, with the liquid ejection head of this embodiment, there is no noticeable unevenness due to the time difference when ejecting secondary color ink between the “non-connecting portion” and the “connecting portion.” In this way, with the technology disclosed herein, it is possible to provide a liquid ejection head in which the element substrate is made smaller while suppressing the occurrence of unevenness.

[0050] <Comparative Example> In the following, two comparative examples will be presented to explain the effect of suppressing unevenness in this embodiment. Note that descriptions of configurations that are the same as or correspond to those in this embodiment will be omitted as appropriate, and differences will be mainly described.

[0051] FIG. 8 is a diagram showing the effect of suppressing unevenness in the third comparative example.

[0052] As shown in FIG. 8, the shape of the element substrate 701 in the third comparative example is a substantially parallelogram, and the ejection element arrays for two colors are arranged on one element substrate, which is different from the present embodiment. Also, one element substrate 701 in this comparative example includes an ejection element array 721 and an ejection element array 722, and each ejection element array ejects ink of a different color, which is different from the present embodiment. In this comparative example, the distance between the ejection element arrays in the "non-connecting portion" (region 711 and region 712) (distance indicated by "D1" in the figure) is different from the distance between the ejection element arrays in the "connecting portion" (region 713) (distance indicated by "D2" in the figure). In other words, the difference between D1 and D2 is not small, and it can be said that the distance between the ejection element arrays ejecting ink of different colors is not the same in the "non-connecting portion" and the "connecting portion". That is, in a recording medium transported at a constant speed in the +Y direction, the time difference between when the ejection element array 722 applies ink and when the ejection element array 721 applies ink differs between the "joint portion" and the "non-joint portion". Therefore, in a configuration like this comparative example, unevenness due to the time difference of secondary colors becomes noticeable between the "non-joint portion" and the "joint portion". For example, assume that magenta ink is ejected from the ejection element array 721, and then cyan ink is ejected from the ejection element array 722 in this order. In this case, when the ink hits the recording medium, the penetration speed into the recording medium differs for each color, and beading may occur, resulting in unevenness.

[0053] FIG. 9 is a diagram showing the effect of suppressing unevenness in the fourth comparative example.

[0054] As shown in FIG. 9, this comparative example differs from the present embodiment in that two element substrates each ejecting ink of a different color are arranged in a staggered manner as a set of element substrate groups. For example, assume that cyan ink is ejected from the fifth element substrate 801, and magenta ink is ejected from the sixth element substrate 802. Even with the configuration of this comparative example, the distance between the ejection element arrays ejecting ink of different colors in the "non-joining portion" is no longer equal to the distance between the ejection element arrays ejecting ink of different colors in the "joining portion". In other words, the distance "D1" between the ejection element arrays ejecting ink of different colors in the regions 811 and 812 is no longer equal to the distance "D2" between the ejection element arrays ejecting ink of different colors in the region 813.

[0055] Therefore, with a configuration such as that of this comparative example, unevenness due to the time difference when ejecting secondary color ink between the "non-joining portion" and the "joining portion" becomes noticeable.

[0056] <Summary> As explained above, by arranging the distance from an ejection element array that ejects liquid to an ejection element array that ejects liquid of a different color from the ejection element array so that it is equal in the "connecting portion" and the "non-connecting portion," it is possible to suppress unevenness caused by the time difference when ejecting liquid.

[0057] In this embodiment, magenta and cyan have been used as examples of ink colors. For example, when using inks of more colors (generally four or more colors of YMCK), the effect of unevenness due to the time difference when ejecting liquid may become more noticeable. For this reason, the configuration of this embodiment is more effective.

[0058] Furthermore, as described above, by arranging each electrical wiring member 105 further toward the tip side in the arrangement direction and extending in the same direction to the outside of the long side of the liquid ejection head 100, it is possible to achieve both miniaturization of the element substrate 104 and reliability of the electrical connection.

[0059] Therefore, according to the technique of the present disclosure, it is possible to provide a small-sized, highly reliable liquid ejection head.

[0060] [Example of application] In general, in the case of a line head in which an element substrate is arranged at an angle to the transport direction to achieve a desired printing width, it is desirable that the distance in the transport direction from the ejection element array at the "connecting portion" to the ejection element array that ejects a liquid of a different color from the ejection element array is short. This is because the smaller the distance in the transport direction from the ejection element array at the "connecting portion" to the ejection element array that ejects a liquid of a different color from the ejection element array, the more the generation of airflow can be suppressed. The relationship between the distance of the connecting portion and the inclination of the element substrate will be described below with reference to Figures 10 and 11.

[0061] <Relationship between the distance and inclination between two adjacent element substrates> FIG. 10 is a diagram for explaining an application example of this embodiment.

[0062] 10, when multiple element substrates 104 ejecting ink of the same color are arranged in-line close to each other, the airflow that flows in as the recording medium is transported is obstructed by the airflow that accompanies the ejection of ink from each ejection port 201. For this reason, it can be said that the smaller the distance between the ejection element arrays on two adjacent element substrates 104 at the "connecting portion", the less likely the airflow that accompanies the transport of the recording medium will flow in. In other words, it can be said that the shorter the distance 901 shown in the figure, the more the airflow that accompanies the transport of the recording medium is suppressed. As a result, in the "connecting portion" in this case, the airflow that accompanies the transport of the recording medium is reduced, and thus the distortion of the droplets ejected from each ejection port 201 is also suppressed.

[0063] For the sake of convenience, the following description will be given by calling the element substrate on the left side of the three element substrates shown in FIG. 10 the first element substrate, and calling the element substrate in the center of the figure adjacent to the first element substrate the second element substrate. For example, the distance between the first ejection element of the first element substrate and the second ejection element of the second element substrate adjacent to the first element substrate, which is disposed at the same position as the first ejection element in the predetermined direction, in a direction perpendicular to the predetermined direction, is preferably 2.6 mm or less. In other words, the distance between the first ejection element of the first element substrate and the second ejection element of the second element substrate adjacent to the first element substrate, which is disposed at the same position as the first ejection element in the X direction, in the Y direction perpendicular to the X direction, is preferably 2.6 mm or less. With this configuration, it is possible to suppress the generation of airflow due to the conveyance of the recording medium.

[0064] <Comparative Example> In the following, a comparative example will be shown and described to explain the relationship between the distance and the inclination between two adjacent element substrates in this embodiment. Note that the description of the same or corresponding configuration as in this embodiment will be omitted as appropriate, and the description will focus on the differences.

[0065] FIG. 11 is a diagram for explaining the fifth comparative example.

[0066] As shown in FIG. 11, in this comparative example, a plurality of element substrates 1001 are arranged at a greater inclination (closer to 90°) than in the application example shown in FIG. 10. The distance between two adjacent element substrates 1001 is also greater than in the application example shown in FIG. 10. As a result, in this comparative example, the distance from the discharge element array 1003 of the element substrate 1001 to the discharge element array 1003 of the element substrate 1001 adjacent to the element substrate 1001 (distance 1105 shown in the figure) is also greater than in the application example shown in FIG. 10. And, between the two adjacent discharge element arrays, airflow due to the conveyance of the recording medium is also likely to occur. As a result, the amount of airflow flowing in between the two adjacent discharge element arrays at the "connecting portion" is greater than in the application example shown in FIG. 10, so that the distortion of the droplets discharged from the discharge port also increases. Therefore, in order to suppress the distortion of the droplets due to the airflow flowing in the "connecting portion", it is important to bring the two adjacent discharge element arrays closer to each other at the "connecting portion".

[0067] Returning now to Fig. 10, the description of the application example of this embodiment will be continued. As shown in Fig. 10, in order to bring a plurality of ejection element arrays 202 that eject ink of the same color closer to each other, it is preferable to make the angle at which the element substrate 104 is arranged smaller (closer to 0°).

[0068] As described above, the multiple element substrates 104 are arranged along a predetermined direction (e.g., the X direction in the figure) that is inclined with respect to the arrangement direction in which the multiple ejection elements are arranged. As an example, when the printing width (i.e., the length in the longitudinal direction of the element substrate 104) is a typical 0.85 inch, the predetermined direction (the X direction in the figure) is inclined at about 7° with respect to the arrangement direction. In other words, it can be said that the element substrate 104 is arranged at an inclination of about 7° with respect to the X direction in the figure. By arranging the multiple element substrates 104 at an incline in this manner, the multiple ejection element arrays 202 that eject ink of the same color can be brought closer to each other.

[0069] In this case, in order to prevent two adjacent element substrates 104 from interfering with each other, it is preferable to make the length of the element substrate 104 in the direction intersecting the arrangement direction smaller. For example, it is preferable to configure the length of the element substrate 104 in the direction intersecting the arrangement direction to be 1.5 mm or less. More specifically, when the shape of the element substrate 104 is substantially rectangular, it is preferable to configure the length of the short side of the element substrate 104 to be 1.5 mm or less. In other words, it is preferable to configure the width w1 of the element substrate 104 to be smaller than the width w2 of the element substrate 1001 (see FIG. 11).

[0070] Furthermore, by making the element substrate 104 smaller, in addition to suppressing the generation of airflow caused by the transport of the recording medium, the manufacturing cost of the element substrate 104 can also be reduced. The greater the distance (distance 901 in the figure) from the ejection element array 202 of the element substrate 104 to the ejection element array 202 of the element substrate 104 adjacent to the element substrate 104, the greater the inclination of the element substrate 104. Therefore, the greater the distance from the ejection element array 202 of the element substrate 104 to the ejection element array 202 of the element substrate 104 adjacent to the element substrate 104, the greater the length of the element substrate 104 relative to the effective print length 902. In other words, the manufacturing cost of the element substrate 104 increases by the amount that the length of the element substrate 104 increases.

[0071] Also, from the viewpoint of miniaturizing the element substrate 104, it is preferable to shorten the distance from one ejection element array 202 of an element substrate 104 to another ejection element array 202 of an element substrate 104 adjacent to the element substrate 104. In addition, it can be said to be important to arrange the ejection element arrays at a high density, or to make the wiring multi-layered in order to miniaturize the circuit area occupied by the element substrate 104.

[0072] According to the technology disclosed herein, it is possible to provide an element substrate that is small and has highly reliable electrical connections. It is also possible to provide a liquid ejection head that is small and has reduced unevenness. In other words, according to the technology disclosed herein, it is possible to provide an element substrate and a liquid ejection head that are small and highly reliable.

[0073] [Second embodiment] In this embodiment, a liquid ejection head having a function of circulating one color of liquid will be described. In the following, the same names and symbols will be used for configurations that are the same as or correspond to those in the first embodiment, and descriptions will be omitted, and differences will be mainly described.

[0074] FIG. 12 is a perspective view that diagrammatically shows a cross section of a third liquid ejection head 1100 according to the second embodiment.

[0075] 12, a supply flow path 1101 through which the liquid flows when the liquid is ejected, and a recovery flow path 1102 through which the liquid flows when the liquid not ejected is recovered are formed in the first flow path member 101 in the third liquid ejection head 1100. In other words, it can be said that the flow path portion in this embodiment is formed with a recovery flow path that recovers the liquid not ejected from the ejection elements.

[0076] FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG.

[0077] 13, the third liquid ejection head 1100 in this embodiment includes a first connection flow path 1201 that communicates the supply flow path 1101 with the element substrate 104 in a stacked state of a first flow path member 101 and a second flow path member 102. Similarly, the third liquid ejection head 1100 includes a second connection flow path 1202 that communicates the element substrate 104 with the recovery flow path 1102.

[0078] When the liquid is being ejected, the liquid flows through the supply flow path 1101 and the first connection flow path 1201 in this order, and is ejected from the ejection port 201 of the element substrate 104. However, there are cases where the liquid supplied to the element substrate 104 is not all ejected from the ejection port 201. The liquid that is not ejected from the ejection port 201 flows to the recovery flow path 1102 via the second connection flow path 1202. For example, this flow can recover the ejection port 201 that is not ejecting, the thickened ink caused by evaporation from the ejection port 201, air bubbles, etc., to the recovery flow path 1102. Furthermore, it is also possible to suppress the ink in the ejection port 201 from thickening. The liquid recovered to the recovery flow path 1102 is recovered to the recovery path of the liquid ejection device main body. That is, in this embodiment, the liquid circulates between the liquid ejection device main body and the third liquid ejection head 1100.

[0079] Generally, when ink circulation is performed, ink containing solid components and high concentration is often ejected. Therefore, the amount of pigment, emulsion, etc. tends to increase. In such a case, the ink aggregation on the recording medium is more likely to change than with conventional inks, and unevenness due to time differences between the "non-joining part" and the "joining part" may become noticeable.

[0080] As the amount of solid components such as pigments and emulsions increases, the ink is more likely to adhere to the ejection surface, and a liquid that dissolves the adhered matter may be applied by wiping or the like. Therefore, in this embodiment as well, it is preferable to arrange the end of the ejection element array in the arrangement direction and the terminal of the electrical connection portion farther apart. By increasing the distance from the tip of the ejection element array in the arrangement direction to the terminal of the electrical connection portion, reliability is further ensured.

[0081] Therefore, even if the liquid ejection head has a circulation function, it can be said that a configuration in which each electrical wiring member is arranged further toward the tip side in the arrangement direction and extends in the same direction to the outside of the long side of the liquid ejection head is effective. In other words, according to the technology disclosed herein, it is possible to provide a small and highly reliable element substrate and liquid ejection head.

[0082] <Comparative Example> In the following, in order to explain the effect of circulation in this embodiment, a comparative example will be shown and described. Note that, as appropriate, explanations of configurations that are the same as or correspond to those in this embodiment will be omitted, and differences will be mainly described.

[0083] FIG. 14 is a diagram for explaining the sixth comparative example.

[0084] In the liquid ejection head 1300 of this comparative example, multiple color liquids are ejected from one element substrate 104.

[0085] As shown in FIG. 14, a liquid ejection head 1300 in this comparative example includes a supply flow path 1301 , a supply flow path 1302 , a supply flow path 1303 , and a supply flow path 1304 .

[0086] The liquid ejection head 1300 further includes a connection flow path 1305, a connection flow path 1306, a connection flow path 1307, and a connection flow path 1308. The liquid ejection head 1300 further includes a recovery flow path 1311, a recovery flow path 1312, a recovery flow path 1313, and a recovery flow path 1314. The liquid ejection head 1300 further includes a connection flow path 1315, a connection flow path 1316, a connection flow path 1317, and a connection flow path 1318.

[0087] For example, when yellow ink is ejected, the ink is supplied from the supply flow path 1301 to the element substrate 104 via the connection flow path 1305. When magenta ink is ejected, the ink is supplied from the supply flow path 1302 to the element substrate 104 via the connection flow path 1306. When cyan ink is ejected, the ink is supplied from the supply flow path 1303 to the element substrate 104 via the connection flow path 1307. When black ink is ejected, the ink is supplied from the supply flow path 1304 to the element substrate 104 via the connection flow path 1308.

[0088] Conversely, when yellow ink is recovered, the ink is recovered from the element substrate 104 to the recovery channel 1311 via the connection channel 1315. When magenta ink is recovered, the ink is recovered from the element substrate 104 to the recovery channel 1312 via the connection channel 1316. When cyan ink is recovered, the ink is recovered from the element substrate 104 to the recovery channel 1313 via the connection channel 1317. When black ink is recovered, the ink is recovered from the element substrate 104 to the recovery channel 1314 via the connection channel 1318.

[0089] As described above, when four colors of ink are supplied to and recovered from one element substrate, not only does the opening area of ​​each supply flow path and each recovery flow path become large, but a supply flow path and a recovery flow path are required for each color of ink. This makes the width (here, the length in the short direction) of the liquid ejection head 1300 extremely large. In addition, the length of each connecting flow path also becomes long, and the shape of each connecting flow path becomes complex. This also increases the effect of pressure loss in the ink flowing in each connecting flow path. Therefore, with such a configuration, it becomes difficult to eject high-viscosity ink or ink at a large flow rate.

[0090] Furthermore, even if the element substrate is made smaller, the density of the ejection ports in the ejection element array increases. Therefore, in a liquid ejection head that has one element substrate that ejects inks of multiple colors and has a circulation function, it becomes difficult to eject high-viscosity ink or ink at a large flow rate due to pressure loss of the liquid flowing in the connecting flow path.

[0091] From the above, it can be said that by configuring one element substrate to eject ink of one color, it is possible to realize a smaller element substrate and simplify the configuration of the connection flow paths. In other words, it can be said that configuring one element substrate to eject ink of one color is effective.

[0092] [Third embodiment] In the second embodiment, a liquid ejection head having a function of circulating one color of liquid was described. Next, a liquid ejection head having a function of circulating two colors of liquid will be described as the third embodiment. Hereinafter, the same names and symbols will be used for configurations that are the same as or correspond to the first and second embodiments, and descriptions will be omitted, and differences will be mainly described.

[0093] FIG. 15 is a perspective view that illustrates an example of a liquid ejection head according to the present embodiment.

[0094] 15, the fourth liquid ejection head 1500 in this embodiment differs from the first embodiment in that a plurality of electrical wiring members 105 extend in opposite directions (in the illustrated example, in the -Y direction and the +Y direction). The fourth liquid ejection head 1500 also differs from the first embodiment in that two types of liquid circulate inside the fourth liquid ejection head 1500.

[0095] FIG. 16 is a schematic top view of a fourth liquid ejection head 1500 in this embodiment.

[0096] 16, an element substrate 104 having a first ejection element array 1501 and an element substrate 104 having a second ejection element array 1502, which eject different types of liquid, are arranged in line on the upper surface of the second flow path member 102. In this embodiment, the electrical wiring member 105 electrically connected to the element substrate 104 having the first ejection element array 1501 extends in the +Y direction. In contrast, the electrical wiring member 105 electrically connected to the element substrate 104 having the second ejection element array 1502 extends in the -Y direction. In other words, the electrical wiring members electrically connected to the electrical connection parts of the element substrates ejecting different colors of liquid extend in opposite directions.

[0097] FIG. 17 is a perspective view that diagrammatically shows a cross section of a fourth liquid ejection head 1500 according to the present embodiment.

[0098] 17, a first supply flow path 1601 through which liquid flows when the liquid is ejected is formed in the first flow path member 101 in the fourth liquid ejection head 1500. Furthermore, a second supply flow path 1603 through which a liquid different from the liquid flowing through the first supply flow path 1601 flows is formed in the first flow path member 101 in this embodiment.

[0099] Conversely, a first recovery flow path 1602 through which liquid flows when recovering the same type of liquid as that flowing through the first supply flow path 1601 is formed in the first flow path member 101 in the fourth liquid ejection head 1500. Similarly, a second recovery flow path 1604 through which liquid flows when recovering the same type of liquid as that flowing through the second supply flow path 1603 is formed in the first flow path member 101 in the fourth liquid ejection head 1500. In other words, it can be said that the flow path section in this embodiment is formed with a second supply flow path 1603 that supplies a different type of liquid from the liquid flowing through the first supply flow path 1601.

[0100] The fourth liquid ejection head 1500 can be said to have a third element substrate on which a first ejection element array 1501 that ejects liquid supplied from a second supply flow path 1603 is arranged, and a second electrical connection member that is electrically connected to the third element substrate. Furthermore, the third element substrate is arranged along a predetermined direction (for example, the X direction in the figure), and the second electrical connection member extends in a direction (+Y direction) opposite to the direction in which the electrical connection member on which the second ejection element array 1502 is arranged extends (-Y direction). In addition, the flow path portion in this embodiment can be said to have a second recovery flow path 1604 that recovers liquid that has not been ejected from the third element substrate.

[0101] With this configuration, even when two types of liquid circulate inside one liquid ejection head, it is possible to both suppress unevenness and reduce the size of the element substrate. In other words, the technology disclosed herein can provide a small, highly reliable element substrate and liquid ejection head.

[0102] [Other embodiments] The configurations of the first to third embodiments described above can also be combined with each other.

[0103] In the first to third embodiments, ink is given as an example of the liquid, but the liquid does not have to be ink. For example, various recording liquids including a treatment liquid used for the purpose of improving the fixation of the ink on the recording medium, reducing uneven gloss, and improving abrasion resistance may be used.

[0104] The disclosure of this embodiment includes the following configuration.

[0105] [Configuration 1] a plurality of element substrates on which a plurality of ejection elements that eject the same type of liquid are arranged; a plurality of electrical wiring members for supplying power to each of the plurality of element substrates; A liquid ejection head having the plurality of element substrates are arranged along a predetermined direction that is inclined with respect to a direction in which the plurality of ejection elements are arranged, each of the plurality of electrical wiring members is disposed at an end of the element substrate in a direction in which the plurality of ejection elements are arranged, and extends from each of the plurality of element substrates in the same direction intersecting the predetermined direction; A liquid ejection head comprising:

[0106] [Configuration 2] the plurality of element substrates are configured to include areas in which the ejection element arrays of two adjacent element substrates overlap each other in a direction intersecting the predetermined direction; A liquid ejection head according to configuration 1.

[0107] [Configuration 3] The length of the element substrate in a direction intersecting the arrangement direction is 1.5 mm or less. 3. The liquid ejection head according to configuration 1 or 2.

[0108] [Configuration 4] The predetermined direction is inclined at about 7° with respect to the arrangement direction. 4. The liquid ejection head according to any one of configurations 1 to 3.

[0109] [Configuration 5] a first ejection element of a first element substrate in two adjacent element substrates; a distance between a second ejection element of a second element substrate adjacent to the first element substrate and a second ejection element disposed at the same position as the first ejection element in the predetermined direction, in a direction perpendicular to the predetermined direction, is 2.6 mm or less; 5. The liquid ejection head according to any one of configurations 2 to 4.

[0110] [Configuration 6] Further comprising a flow path portion in which a supply flow path is formed to supply a liquid to the element substrate. The liquid ejection head according to configuration 1 or 5.

[0111] [Configuration 7] A recovery flow path that recovers liquid that has not been ejected from the ejection element is formed in the flow path portion. A liquid ejection head according to configuration 6.

[0112] [Configuration 8] a second supply flow path is formed in the flow path section to supply a liquid of a different type from the liquid flowing through the supply flow path; a third element substrate that ejects the liquid supplied from the second supply flow path; a second electrical connection member electrically connected to the third element substrate; having the third element substrate is arranged along the predetermined direction, The second electrical connection member extends in a direction opposite to the direction in which the electrical connection member extends. A liquid ejection head according to configuration 7.

[0113] [Configuration 9] a second recovery flow path that recovers liquid that has not been ejected from the third element substrate is formed in the flow path portion; A liquid ejection head according to configuration 8.

[0114] [Configuration 10] A liquid ejection head according to configuration 1, A liquid delivery unit for supplying liquid to the liquid ejection head according to configuration 1; having A liquid ejection device comprising:

[0115] [Configuration 11] the liquid delivery unit for supplying ink to the liquid ejection head according to configuration 1; a conveying means for conveying a recording medium onto which the ink is to land; having A liquid ejection device according to configuration 10.

[0116] [Configuration 12] an element substrate having an ejection element array in which a plurality of ejection elements that eject the same type of liquid are arranged, and an electrical connection portion disposed at an end of the ejection element array in the direction of the arrangement; an electrical connection member electrically connected to the electrical connection portion and extending in a direction intersecting the arrangement direction; having A dispensing module comprising:

Claims

1. A plurality of element substrates on which a plurality of ejection elements for ejecting the same type of liquid are arranged, A plurality of electrical wiring members for supplying power to each of the plurality of element substrates, A liquid ejection head having, The plurality of element substrates are arranged along a second direction having an inclination with respect to a first direction in which the plurality of ejection elements are arranged, The electrical wiring member is connected to an electrical connection portion provided at an end portion of the element substrate in the first direction, and extends from the electrical connection portion in a third direction intersecting the first direction and the second direction, A liquid ejection head characterized by the above.

2. The plurality of element substrates are configured to include a connection region in which ejection element rows in two adjacent element substrates overlap in a direction intersecting the second direction with each other, The liquid ejection head according to Claim 1.

3. The electrical connection portion is provided between the ejection element at the end portion in the first direction and the end portion of the element substrate, The liquid ejection head according to Claim 1 or 2.

4. The electrical connection portion is not provided at a substantially central portion of the element substrate in the first direction. The liquid ejection head according to Claim 1 or 2.

5. The electrical connection portion is provided in the connection region, The liquid ejection head according to Claim 2.

6. The shape of the element substrate is substantially rectangular, The liquid ejection head according to Claim 1 or 2.

7. The length of the element substrate in a direction intersecting the first direction is 1.5 mm or less, The liquid ejection head according to Claim 1 or 2.

8. Between the first ejection element of the first element substrate and the second ejection element of the second element substrate adjacent to the first element substrate, The distance in the third direction between the second ejection element arranged at the same position as the first ejection element in the second direction is 2.6 mm or less, The liquid ejection head according to Claim 2.

9. Further having a flow path portion in which a supply flow path for supplying liquid to the element substrate is formed, The liquid ejection head according to Claim 1.

10. A recovery flow path for recovering the liquid not ejected from the ejection element is formed in the flow path portion, The liquid ejection head according to Claim 9.

11. A second supply flow path for supplying a liquid of a type different from the liquid flowing through the supply flow path is formed in the flow path portion, A third element substrate that discharges the liquid supplied from the second supply flow path; A second electrical wiring member electrically connected to the third element substrate; having; The third element substrate is arranged along the second direction; The second electrical wiring member extends in a direction opposite to the direction in which the electrical wiring member extends; The liquid discharge head according to claim 10.

12. A second recovery flow path for recovering the liquid that has not been discharged from the third element substrate is formed in the flow path portion; The liquid discharge head according to claim 11.

13. The liquid discharge head according to claim 1 or 2; A liquid feeding unit for supplying liquid to the liquid discharge head; having; A liquid discharge device characterized by this.

14. Further comprising a conveying means for conveying a recording medium on which ink lands; The liquid discharge device according to claim 13.

15. An element substrate having a discharge element row in which a plurality of discharge elements that discharge the same type of liquid are arranged along a first direction, and an electrical connection portion arranged at an end of the discharge element row in the direction of the arrangement; An electrical connection member that is electrically connected to the electrical connection portion and extends in a direction intersecting the first direction; having; A discharge module characterized by this.

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