Recording element substrate, liquid ejection head, and liquid ejection device

Abstract

The objective is to provide a recording element substrate in which recording elements, circulating elements, and wiring are efficiently arranged. [Solution] The recording element substrate includes a first unit including a first element and a second element, a second unit including a third element and a fourth element, and power wiring including a first portion and a second portion. The power wiring includes an extended portion that extends along the boundary line between the first unit and the second unit. The first element and the third element are arranged symmetrically with respect to the extended portion. The second element and the fourth element are arranged symmetrically with respect to the extended portion. The first portion and the second portion are arranged symmetrically with respect to the extended portion.

Description

Technical Field

[0001] The present disclosure relates to a recording element substrate, a liquid ejection head, and a liquid ejection device.

Background Art

[0002] Generally, a liquid ejection head that ejects liquid for recording includes a liquid ejection head that ejects liquid. The liquid ejection head includes a recording element substrate including an energy generating element (recording element) that generates energy for ejecting liquid.

[0003] In addition, when the liquid ejection head is not used for a long time, there is a risk that the liquid may concentrate or thicken inside the liquid ejection head. In order to suppress such a situation, liquid circulation may be performed.

[0004] Patent Document 1 discloses a recording element substrate including a first pump that circulates liquid between a common flow path and a pressure chamber formed in the recording element substrate, a second pump provided at a position different from the recording element substrate, and a recording element.

[0005] According to the recording element substrate of Patent Document 1, even after a long period in which liquid is not ejected, by performing liquid circulation using the first pump and the second pump, ejection of the desired liquid from the ejection port can be achieved.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Incidentally, the recording element substrate described in Patent Document 1 has a substrate (element substrate) that includes a first pump (circulation element) and recording elements. Although not mentioned in Patent Document 1, the substrate of the recording element substrate is provided with various drivers and various wirings to drive the first pump and recording elements. In order to suppress the increase in size, there was room to improve the arrangement of the recording elements, circulation elements, and wiring in the recording element substrate of Patent Document 1.

[0008] Therefore, the present invention aims to provide a recording element substrate in which recording elements, circulating elements, and wiring are efficiently arranged. [Means for solving the problem]

[0009] The recording element substrate comprises a first unit including a first element and a second element, a second unit including a third element and a fourth element, and power supply wiring including a first portion for supplying power to the first unit and a second portion for supplying power to the second unit, wherein the power supply wiring includes an extended portion extending along the boundary line between the first unit and the second unit, the first element and the third element are arranged symmetrically with respect to the extended portion, the second element and the fourth element are arranged symmetrically with respect to the extended portion, and the first portion and the second portion are arranged symmetrically with respect to the extended portion. [Effects of the Invention]

[0010] The technology of this disclosure provides a recording element substrate in which recording elements, circulating elements, and wiring are efficiently arranged. [Brief explanation of the drawing]

[0011] [Figure 1] A diagram showing an example of a liquid dispensing device that can be applied to one embodiment. [Figure 2] A diagram showing an example of a liquid dispensing head that can be applied to one embodiment. [Figure 3] A diagram illustrating the configuration of a flow path that can be applied to one embodiment. [Figure 4] A diagram for explaining the principle of generation of the circulation flow. [Figure 5] An explanatory diagram showing how the concentration of the liquid is eliminated. [Figure 6] A diagram showing an example of a circuit configuration applicable to one embodiment. [Figure 7] A schematic diagram showing an example of a circuit applicable to one embodiment. [Figure 8] A schematic diagram showing the arrangement on an element substrate applicable to one embodiment. [Figure 9] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 10] A diagram showing a comparative example of the wiring configuration of the element substrate. [Figure 11] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 12] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 13] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 14] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 15] A schematic enlarged view showing a part of a wiring configuration applicable to one embodiment. [Figure 16] A schematic diagram of the vicinity of a discharge port applicable to one embodiment. [Figure 17] A schematic diagram of the vicinity of a discharge port applicable to one embodiment. [Figure 18] A schematic diagram of the vicinity of a discharge port applicable to one embodiment. [Figure 19] A diagram showing an example of a recording element substrate applicable to one embodiment. [Figure 20] A diagram showing an example of a liquid discharge device applicable to one embodiment. [Figure 21] A schematic cross-sectional view of a recording element substrate applicable to one embodiment.

Best Mode for Carrying Out the Invention

[0012] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the present disclosure, and not all combinations of features described in these embodiments are essential for the solution of the present disclosure. The same components are denoted by the same reference numerals, and descriptions of components with common reference numerals are omitted as appropriate. In the following description, first, the basic configuration of the present disclosure will be described, and then the characteristic parts of the present disclosure will be described.

[0013] [First Embodiment] <Liquid ejection device 50> FIG. 1 is a schematic perspective view showing an example of a liquid ejection device 50 applicable to the present embodiment.

[0014] The liquid ejection device 50 shown in FIG. 1 can perform recording by ejecting liquid onto a recording medium P by a liquid ejection head 1 that scans in a scanning direction (X direction) intersecting the conveyance direction (Y direction) of the recording medium P in a plane. That is, in the present embodiment, a so-called serial type liquid ejection device 50 is used. The liquid ejection head 1 can eject liquid (for example, ink). For example, four types of ink, black (K), cyan (C), magenta (M), and yellow (Y), are ejected from the liquid ejection head 1. The liquid ejection head 1 can eject these inks to record a full-color image. The ink ejected from the liquid ejection head 1 is not limited to the above four types of ink. Other types of ink may be ejected from the liquid ejection head 1. That is, the type and number of inks ejected by the liquid ejection head 1 are not limited.

[0015] The liquid discharge head 1 is detachably mounted on the carriage 60. The carriage 60 reciprocates along the guide axis 51 in the main scanning direction (X direction). The recording medium P is transported by the transport means in a transport direction (Y direction) that intersects (orthogonal in this embodiment) with the scanning direction (X direction). The transport means includes a first transport roller 55, a second transport roller 56, a third transport roller 57, and a fourth transport roller 58. In the figures referenced below, the Z direction represents the vertical direction and intersects (orthogonal in this embodiment) with the XY plane defined by the X and Y directions.

[0016] In this embodiment, a main tank 2, which functions as a liquid storage unit, is provided outside the liquid discharge head 1. The liquid stored in the main tank 2 is supplied to a sub-tank 54 of the liquid discharge head 1 via a supply tube 59 or the like by the driving force of an external pump 61. The liquid discharge head 1 is fixed to the carriage 60 by a positioning unit (not shown) and electrical contacts. The liquid discharge head 1 discharges liquid while moving in the scanning direction (X direction) together with the carriage 60 and records it on the recording medium P.

[0017] An external pump 61, which is connected to the main tank 2 that serves as the ink supply source, is connected to a supply tube 59. A connector (not shown) is provided at the end of the supply tube 59. With the liquid dispensing head 1 mounted on the liquid dispensing device 50, the connector at the other end of the supply tube 59 is liquid-tightly connected to the connector insertion port, which is the liquid inlet, provided on the housing 53 of the liquid dispensing head 1 (see Figure 2(a)). This forms a liquid supply path from the main tank 2 through the external pump 61 to the liquid dispensing head 1.

[0018] In this embodiment, the four types of liquids described above are used. Therefore, four sets of the main tank 2, external pump 61, supply tube 59, and sub-tank 54 are provided, each corresponding to one of the four types of liquids. In other words, in this embodiment, four independent liquid supply paths corresponding to each type of liquid are formed. Thus, the liquid discharge device 50 of this embodiment is equipped with a liquid supply system from which liquid is supplied from the main tank 2.

[0019] Furthermore, the liquid dispensing device 50 of this embodiment does not include a liquid recovery system for recovering the liquid remaining inside the liquid dispensing head 1 into the main tank 2. Therefore, the liquid dispensing head 1 is provided with a connector insertion port for connecting a tube for recovering the liquid.

[0020] <Liquid dispensing head 1> Figure 2(a) is an exploded perspective view showing an example of a liquid dispensing head 1 that can be applied to this embodiment.

[0021] As shown in Figure 2(a), the liquid discharge head 1 includes a sub-tank 54 for temporarily storing liquid internally, and a recording element substrate 3 for discharging the liquid supplied from the sub-tank 54 onto the recording medium P (see Figure 1). The liquid discharge head 1 also includes a channel forming substrate 4 having a channel connecting the sub-tank 54 and the recording element substrate 3, a support substrate 7 supporting the channel forming substrate 4, and a face cover 5 covering the support substrate 7 except for the recording element substrate 3.

[0022] In the liquid dispensing head 1, liquid dispensing may become unstable. For example, if volatile components (e.g., water) evaporate from the dispensing port 11 (see Figure 2(b), etc.) and solid components in the liquid concentrate near the port 11, liquid dispensing becomes unstable. Various modifications can be made to the liquid dispensing head 1 to suppress such situations.

[0023] One example of this design is to provide a cap member (not shown) that covers the discharge port surface where the discharge port 11 is formed, at a position off-center in the X direction from the transport path of the recording medium P (see Figure 1). By covering and protecting the discharge port surface with the cap member when recording is not in operation, drying of the discharge port 11 can be suppressed, and evaporation of volatile components can be inhibited.

[0024] Furthermore, a suction mechanism (not shown) for drawing in liquid may be provided. In this case, the cap member is used to perform a suction operation, such as drawing liquid from the discharge port 11. By performing this suction operation, the liquid near the discharge port 11 is refreshed, and the quality of the resulting image can be maintained.

[0025] Furthermore, when recording is not in progress, pre-discharge may be performed and the concentrated liquid may be discarded. In addition, during recording, a small amount of liquid may be pre-discharged to a location on the recording medium P that is not visually noticeable.

[0026] Pre-discharge and suction operations contribute significantly to maintaining image quality. On the other hand, pre-discharge and suction operations require minimizing liquid waste. In contrast, the circulation of liquid within the recording element substrate, as described later, can maintain image quality without discarding liquid, by suppressing liquid concentration and viscosity.

[0027] For example, as in the technology described in Patent Document 1, by driving a pump (circulation element) provided on the substrate of the recording element to circulate the liquid, it is possible to reduce the amount of liquid waste while suppressing drying of the discharge port and concentration of the liquid. With such technology, it is possible to minimize the number of pre-discharge and suction recovery operations. Furthermore, by minimizing the number of pre-discharge and suction operations, throughput and yield can be improved.

[0028] Furthermore, it is not necessary to provide circulation elements in all flow paths (individual flow paths described later) in the liquid discharge head 1. By providing circulation elements in some flow paths, throughput and yield can be improved compared to cases where no circulation elements are provided.

[0029] Furthermore, the liquid dispensing head 1 may be equipped with circulation elements at all locations corresponding to the four types of liquids, or it may be equipped with circulation elements at only one location corresponding to one type of liquid. In other words, the liquid dispensing head 1 may be configured to circulate all four types of liquids, or it may be configured to circulate only one type of liquid.

[0030] <Recording element substrate 3> Figure 2(b) is an overall view showing an example of a recording element substrate 3 that can be applied to this embodiment.

[0031] Figure 2(b) shows a recording element substrate 3 capable of dispensing four types of liquids. The recording element substrate 3 is provided with dispensing ports 11 for dispensing liquids and pads 20 for electrical mounting. For example, black, cyan, magenta, and yellow inks are dispensed from the recording element substrate 3. The dispensing ports 11 for these various liquids are formed along the Y direction (first direction), and these dispensing ports 11 form a row of dispensing ports.

[0032] In each nozzle row, two nozzles 11 are arranged offset from each other along the X direction (second direction), and a number of nozzles 11 are arranged at equal intervals along the Y direction. Alternatively, in each nozzle row, the nozzles 11 may be arranged in a single row along the Y direction without being offset in the X direction. Furthermore, two nozzle rows for dispensing black ink may be formed to create five nozzle rows for dispensing four colors of ink.

[0033] Furthermore, the combinations of liquid types discharged from the recording element substrate 3 are not limited to those described above. Moreover, the types of liquids discharged from the recording element substrate 3 are not limited to the four types described above.

[0034] Figures 3(a) to 3(c) are schematic diagrams illustrating the configuration of the flow channels in the recording element substrate 3 that can be applied to this embodiment.

[0035] Figure 3(a) is a schematic plan view of the vicinity of the discharge port 11 along the direction in which the liquid droplet is discharged. Figures 3(b) and (c) are cross-sectional views taken along the line IIIb-IIIb in Figure 3(a).

[0036] As shown in Figures 3(b) and (c), the recording element substrate 3 comprises an ejection port forming member 19 on which an ejection port 11 is formed, and an element substrate 18 including an energy generating element that supplies energy to the liquid. The element substrate 18 comprises a first ejection element that generates energy for ejecting the liquid, and a first circulation element that generates energy for circulating the liquid.

[0037] In this embodiment, an electrothermal conversion element is used as the first discharge element and the first circulation element. A discharge heater RhA is used as the first discharge element. A circulation heater RhB is used as the first circulation element. A piezoelectric element may be used as the first discharge element, or a piezoelectric element may be used as the first circulation element.

[0038] Furthermore, the element substrate 18 has a first supply port 22 and a second supply port 32 that are connected to the flow path formed in the discharge port forming member 19. In this embodiment, the first supply port 22 and the second supply port 32 are independent supply ports.

[0039] Multiple partition walls 21 are formed on the discharge port forming member 19, separating the interior of the recording element substrate 3 while the discharge port forming member 19 and the element substrate 18 are bonded together. The partition walls 21 extend along the short-side direction (X direction) where the short side of the recording element substrate 3 extends. As a result, straight-type individual channels 23 are formed in the recording element substrate 3 of this embodiment.

[0040] In this disclosure, "straight type" means a shape in which a first discharge element and a first circulation element are arranged on a single flow path, with both ends of the flow path located on either side of the discharge port, and the flow path extends along a direction that intersects the direction in the plane with respect to the direction in which the row of discharge ports extends. That is, in the recording element substrate 3 of this embodiment having a straight-type flow path, a discharge heater RhA and a circulation heater RhB are provided along a direction (second direction, X direction) that is perpendicular in the plane with respect to the direction in which the row of discharge ports extends (first direction, Y direction).

[0041] A filter 31 for removing foreign matter from the liquid may be provided in the flow path of the recording element substrate 3. In this embodiment, the filter 31 is provided on the outside of the individual flow path 23 formed in the discharge port forming member 19. Specifically, the filter 31 is provided on the inlet side and the outlet side of the individual flow path 23. Alternatively, the filter 31 may be provided between the discharge heater RhA and the circulation heater RhB in the individual flow path 23. In this case, the filter 31 does not need to be provided on the upstream side (the side where the circulation heater RhB is provided) on the outside of the individual flow path 23.

[0042] The flow of liquid through the individual channel 23 can be broadly divided into two types. The first is the first flow (circulating flow 27) for circulating the liquid, which is generated by driving the circulating heater RhB. As described above, in the second direction, the ends of the straight individual channel 23 face each other. That is, in the straight individual channel 23, the inlet and outlet of the circulating flow 27 face each other at a distance from each other. With this configuration, since new liquid is supplied from the inlet of the individual channel 23 immediately after the concentrated liquid is discharged from the outlet of the individual channel 23, it is possible to prevent the discharged liquid from entering the inlet of the individual channel 23.

[0043] On the other hand, in the U-shaped flow path described later using Figure 18, the inlet and outlet of the individual flow path are located close to each other, so even if concentrated liquid is discharged from the outlet, that liquid may re-enter from the inlet. In other words, in the U-shaped flow path, even if circulation is performed, the concentration of the liquid may not be sufficiently resolved. However, in the straight-type individual flow path 23, such a situation can be suppressed compared to the U-shaped flow path.

[0044] The second flow occurs when the discharge heater RhA is driven and when refilling after discharge. Below, the first flow will be explained using Figure 3(b), and the second flow will be explained using Figure 3(c).

[0045] Figure 3(b) is a diagram illustrating the first flow. Note that Figure 3(b) is a cross-sectional view taken along the line IIIb-IIIb in Figure 3(a).

[0046] As shown in Figure 3(b), a common channel 24 is formed in the element substrate 18, which is connected to the first supply port 22 and the second supply port 32, respectively. With the element substrate 18 and the discharge port forming member 19 bonded together, the common channel 24 is connected to a channel formed in the member bonded to the surface facing the opposite direction to the direction in which the bonding surface between the element substrate 18 and the discharge port forming member 19 faces. In this way, with the element substrate 18 and the discharge port forming member 19 bonded together, a channel is formed in the element substrate 18 that penetrates the element substrate 18 in the Z direction.

[0047] The discharge port forming member 19 has a first connecting channel 13 located on the inlet (upstream) side of the individual channel 23 and a second connecting channel 25 located on the outlet (downstream) side of the individual channel 23. At one upstream end of the individual channel 23, the first connecting channel 13 is connected to the first supply port 22. At the other downstream end of the individual channel 23, the second connecting channel 25 is connected to the second supply port 32. In this way, both ends of the individual channel 23 are located on opposite sides of the discharge port 11.

[0048] The first connecting channel 13 is located closer to the circulating heater RhB than to the discharge port 11. In Figure 3(b), a liquid meniscus is present at the discharge port 11. That is, the discharge port 11 shown in Figure 3(b) has a discharge port interface formed as the interface between the liquid and the atmosphere. In this state, when the circulating heater RhB, which is located closer to the first supply port 22 than to the second supply port 32, is driven, a circulating flow 27 for circulating the liquid is generated.

[0049] As a circulating flow 27 is generated, the liquid flows in the following order: common channel 24, first supply port 22, first connecting channel 13, individual channel 23, second connecting channel 25, and second supply port 32. The liquid then returns to the common channel 24. In this embodiment, a circulation occurs in which the liquid returning from the second supply port 32 flows back into the first supply port 22 via the common channel 24.

[0050] Figure 3(c) illustrates the second flow. Note that Figure 3(c) also uses the same cross-section as Figure 3(b) for its explanation.

[0051] As shown in Figure 3(c), a discharge heater RhA is provided on the element substrate 18 at a position corresponding to the discharge port 11. The discharge heater RhA is located closer to the second supply port 32 than to the first supply port 22.

[0052] When discharging liquid from the discharge port 11, liquid is supplied from the first supply port 22 and the second supply port 32 to the first connecting channel 13 and the second connecting channel 25, respectively. Then, liquid is refilled into the individual channel 23 from both the first connecting channel 13 and the second connecting channel 25. With the individual channel 23 refilled with liquid, the discharge heater RhA is driven to cause foaming of the liquid present in the individual channel 23, and the resulting foaming energy can be used to discharge droplets from the discharge port 11. In this way, the individual channel 23 in this embodiment also functions as a pressure chamber.

[0053] <Principle of Circulation Flow 27> Figures 4(a) to 4(c) are diagrams illustrating the principle of generating the circulating flow 27. The cross-sections shown in each of Figures 4(a) to 4(c) are the same as those in Figure 3(b). For the sake of explanation, the filter 31 (see Figure 3(a), etc.) is not shown.

[0054] Figure 4(a) shows the growth process of bubbles B after they are generated by film boiling of the liquid due to the operation of the circulating heater RhB. In Figure 4(a), an equivalent circuit is shown in which the first flow resistance R1 and the second flow resistance R2 are likened to electrical resistances.

[0055] As shown in Figure 4(a), when the circulating heater RhB is activated, bubbles B are generated in the liquid flowing through the individual channel 23.

[0056] The circulating heater RhB is located closer to the first supply port 22 than to the second supply port 32. Therefore, the first flow resistance R1 between the circulating heater RhB and the first supply port 22 is smaller than the second flow resistance R2 between the circulating heater RhB and the second supply port 32. Bubbles B, generated by film boiling of the liquid, grow towards the first supply port 22 side where the smaller first flow resistance R1 exists, due to the difference between the first and second flow resistances R2. Consequently, in the individual flow path 23, the liquid flow Fa toward the first supply port 22 is larger than the liquid flow Fb toward the second supply port 32.

[0057] Figure 4(b) illustrates the contraction process of bubble B.

[0058] As shown in Figure 4(b), during the contraction process of bubble B, liquid flows in from the first supply port 22 and the second supply port 32 to compensate for the volume lost due to the contraction of bubble B, generating flows Fc and Fd, respectively. As described above, the first flow resistance R1 on the first supply port 22 side (see Figure 4(a)) is smaller than the second flow resistance R2 on the second supply port 32 side. Therefore, the liquid flow Fc that flows in from the first supply port 22 is larger than the liquid flow Fd that flows in from the second supply port 32. Also, bubble B contracts on the second supply port 32 side of the circulating heater RhB. Then, bubble B disappears at a position shifted on the second supply port 32 side of the circulating heater RhB.

[0059] Figure 4(c) illustrates the process after bubble B has been deflated.

[0060] As described above, the flow Fc is greater than the flow Fd. Therefore, a circulating liquid flow 27 is generated from the first supply port 22 toward the second supply port 32. The magnitude of the circulating flow 27 changes due to the influence of the first flow resistance R1, the second flow resistance R2, and the bubbles B. It is preferable that the circulating heater RhB is located closer to one of the ends of the individual flow path 23 than the discharge heater RhA. Furthermore, it is preferable that the value obtained by dividing the first flow resistance R1 by the second flow resistance R2 (R1 / R2) is between 0.05 and 0.40.

[0061] By setting the value of the first flow resistance R1 / second flow resistance R2 to fall within the above range, the circulating flow 27 can be made to its maximum value. For the circulating flow 27 to be maximized, it is important to increase the liquid flow Fa toward the first supply port 22 and increase the liquid flow Fc flowing in from the first supply port 22. Therefore, it is effective to reduce the first flow resistance R1.

[0062] Furthermore, it is important to minimize the liquid flow Fb toward the second supply port 32 and minimize the liquid flow Fd flowing in from the second supply port 32. Therefore, increasing the second flow resistance R2 is effective. Thus, it is important to make the first flow resistance R1 small and the second flow resistance R2 large, that is, to make the value of the first flow resistance R1 / second flow resistance R2 (R1 / R2) less than 1. Also, a larger bubble B, that is, a larger bubble volume, leads to an increase in the discharge volume of fluid generated in the individual flow channels 23, and thus the circulation flow 27 increases.

[0063] Examples of methods to increase the bubble volume include enlarging the circulating heater RhB and increasing the width and height of the individual flow channels 23 to reduce flow resistance. Other methods include reducing the viscosity of the liquid, increasing the temperature of the liquid discharge head 1 (see Figure 1), and using double pulses for the drive pulse.

[0064] As a portion of the circulating flow 27 enters the discharge port 11, the concentrated liquid inside the discharge port 11 is sent to the second supply port 32. Then, fresh liquid is flowed into the discharge port 11 from the first supply port 22 through the individual flow path 23. In this way, by making it difficult for concentrated liquid to remain inside the discharge port 11, the influence of the concentrated liquid can be suppressed, and the liquid discharge state at the start of the discharge operation can be improved.

[0065] The circulating flow 27 is a transient flow associated with the growth and contraction processes of bubbles B. Therefore, after bubbles B are defoamed, the inertial flow attenuates over time and stops after a certain period. Consequently, in order to generate the circulating flow 27 steadily for a certain period of time, it is necessary to repeatedly drive the circulating heater RhB. The driving cycle of the circulating heater RhB is not limited as long as it is possible to discharge the concentrated liquid in the discharge port 11.

[0066] However, considering the 10 μs cycle time from the generation of bubble B to its elimination, the circulation effect is not very high when driven at a drive frequency of about 100 kHz. Therefore, in order to obtain a suitable circulation effect, it is preferable to drive the circulation heater RhB at a period of, for example, 100 Hz to several tens of kHz.

[0067] Furthermore, the higher the driving frequency, the more the circulating flow 27 is maintained, and the greater the effect of discharging the concentrated liquid. However, it is also necessary to consider that the temperature of the liquid will rise due to the heat generated by driving the circulating heater RhB. Therefore, it is necessary to drive the circulating heater RhB appropriately.

[0068] Figures 5(a) to 5(d) are explanatory diagrams illustrating how liquid concentration is resolved. In Figures 5(a) to 5(d), concentrated areas of the liquid are shown in darker colors, and the degree of concentration is indicated by the shade of color.

[0069] As shown in Figure 5(a), when the circulating heater RhB is temporarily stopped, volatile components in the liquid evaporate from the discharge port 11, and the liquid concentrates near the discharge port 11.

[0070] As shown in Figure 5(b), by driving the circulating heater RhB and generating a circulating flow 27, the concentration of the liquid near the discharge port 11 can be eliminated.

[0071] As shown in Figure 5(c), when the circulating heater RhB is temporarily stopped again, the liquid concentrates near the discharge port 11.

[0072] As shown in Figure 5(d), the circulating heater RhB is driven again to generate a circulating flow 27, thereby eliminating the concentration of the liquid near the discharge port 11.

[0073] As explained above, in the straight-type individual flow path 23, the concentration state of the liquid is reset each time the circulating heater RhB is paused and the circulation operation is repeated.

[0074] <ink> As explained above, in this embodiment, the liquid discharge state can be maintained well by circulating the fluid. Therefore, changes in discharge speed and other factors can be further reduced, and discharge can be stabilized.

[0075] On the other hand, depending on the application of the liquid ejection device 50 (see Figure 1) equipped with the liquid ejection head 1, inks with different types of colorants and solid content may be used. In other words, it is preferable that the liquid ejection head 1 has the performance to maintain a high level of ejection stability regardless of the type of ink used.

[0076] For example, to address issues that may arise from the moisture content in the ink (e.g., curling and cockling on plain paper), inks with reduced water content are sometimes used. Inks with low water content tend to have higher concentrations of solid components other than water, such as organic solvents, pigments, and resins. As a result, inks with low water content are prone to a rapid increase in viscosity as the water evaporates, which can reduce the stability of ink ejection.

[0077] For such inks, the method of generating a circulating flow 27 in the individual channel 23 is very effective because it can suppress an increase in the viscosity of the ink. Generally, inks with a high solid content have a solid content of 10 wt% or more. For example, the technology of this disclosure is preferably applied to inks in which the solid content is 10 wt% (mass%) or more.

[0078] Furthermore, since the viscosity of the ink changes depending on the ink temperature, the temperature at which the liquid ejection head 1 is operated may affect the ink viscosity and, consequently, the ejection stability. Therefore, the entire substrate can be heated to a constant temperature using the circulating heater RhB located on the recording element substrate 3.

[0079] When the circulating heater RhB is driven to generate the circulating flow 27, the instantaneous flow velocity can be within the range of several tens of mm / s to 1000 mm / s. The average flow velocity of the circulating flow 27 on the order of several hundred microseconds depends on the driving frequency of the circulating heater RhB. This is because the circulating flow 27 attenuates over time and stops after a certain period of time. When the circulating heater RhB is driven at approximately the same driving frequency (discharge frequency) as the discharge heater RhA (approximately 10 to 20 kHz), the average flow velocity of the circulating flow 27 can be within the range of several mm / s to 100 mm / s.

[0080] When using pigment ink with a relatively high concentration (for example, ink with a viscosity of 3 cp to 6 cP at the operating temperature of the liquid ejection head 1), the ink tends to thicken at the ejection port 11 depending on the non-ejection time (stop time). Therefore, when using ink with a relatively high pigment concentration, changes in ejection speed are likely to occur, which may lead to a decrease in ejection stability.

[0081] Therefore, in this case, it is necessary to circulate the ink over a relatively short period of time. For example, it is necessary to perform steady-state or transient circulation at a high frequency during the idle time of the liquid ejection head 1 to eliminate ink concentration. When using the circulation heater RhB, transient circulation is performed. Performing transient circulation at a high frequency contributes to eliminating ink concentration at the ejection port 11.

[0082] On the other hand, when using pigment ink with a relatively low concentration (for example, ink with a viscosity of 1 cp or more and 2 cP or less at the operating temperature of the liquid ejection head 1), the ejection speed may change depending on the stopping time of the liquid ejection head 1. However, this effect is relatively small compared to when the ejection speed of high-concentration ink changes.

[0083] Furthermore, depending on the stopping time of the liquid discharge head 1, there is a risk that the ink may become thicker at the discharge port 11. Therefore, when restarting the liquid discharge head 1 after it has been stopped for a certain period of time or longer, it is necessary to perform a recovery process (such as a suction operation, a wiping operation, or a preliminary discharge combining these). However, ink is wasted during the recovery process. Therefore, in this embodiment, the concentration of ink at the discharge port 11 is eliminated without generating waste ink by performing a recovery operation that generates a circulating flow 27.

[0084] Depending on the stopping time of the liquid ejection head 1, it is possible to restore the ejection performance of the liquid ejection head 1 by performing only a circulation operation without generating waste ink. Alternatively, it is possible to restore the ejection performance by performing a circulation operation while also combining it with a suction operation to remove air bubbles inside the head, which is separate from the concentration removal process, in order to minimize waste ink. Regardless of the ink concentration, it is desirable to return the ink to its initial fresh state as much as possible in order to suppress the effects of ink concentration.

[0085] <Element substrate 18> Figure 6 shows an example of a circuit configuration of an element substrate 18 that can be applied to this embodiment.

[0086] As shown in Figure 6, the liquid dispensing device 50 includes a power supply circuit 102 that supplies power to the element substrate 18 and a controller 101 that transmits an enable signal to the element substrate 18.

[0087] The element substrate 18 includes a discharge module 104 for discharging liquid, a circulation module 105 for circulating liquid, and a control data supply circuit 106 for outputting various signals. The element substrate 18 also includes a time-division selection signal line 111, a circulation group selection signal line 110, and a discharge group selection signal line 109 connected to the control data supply circuit 106.

[0088] The discharge module 104 includes a discharge heater RhA, a discharge drive element MD1 for supplying current to the discharge heater RhA, and a discharge wiring 107 for connecting the discharge heater RhA and the discharge drive element MD1. The discharge wiring 107 is a drain wiring. The discharge drive element MD1 is a transistor that drives the discharge heater RhA. The discharge heater RhA may also serve other roles, such as a circulating heater for circulating liquid, an element for heating a specific area of ​​the recording element substrate, or a temperature detection element for monitoring the heater's temperature information.

[0089] The ejection module 104 includes a first logic circuit AND1 for selectively driving the ejection drive element MD1. By passing current through the ejection heater RhA, heat is generated, causing the liquid to foam and be ejected, which can then be recorded onto the recording paper of the recording medium P (see Figure 1). Multiple ejection heaters RhA are arranged in a line along the Y direction to form an ejection heater row 112 (ejection element row).

[0090] The circulation module 105 includes a circulation heater RhB, a circulation drive element MD2 for supplying current to the circulation heater RhB, and a circulation wiring 108 for connecting the circulation heater RhB and the circulation drive element MD2. The circulation wiring 108 is a drain wiring. The circulation drive element MD2 is a transistor for supplying current to the circulation heater RhB. The circulation module 105 includes a second logic circuit AND2 for selectively driving the circulation drive element MD2.

[0091] By passing an electric current through the circulating heater RhB, heat is generated, causing bubbles B to grow and creating a circulating flow 27 in the individual channel 23 (see Figures 4(a) to (c), etc.). Multiple circulating heaters RhB are arranged in a line along the Y direction to form a circulating heater row 113 (circulating element row). The circulating heater RhB may also serve as an ejection heater for discharging liquid, an element for heating a specific area of ​​the recording element substrate, or a temperature detection element for monitoring the heater's temperature information.

[0092] The ejection module 104 receives the ejection group selection signal, time-division selection signal, and enable signal (which controls the pulse width, or the time the ejection drive element MD1 is turned on and current is flowing) from the control data supply circuit 106 as inputs to the first logic circuit AND1. The ejection group selection signal is input via the ejection group selection signal line 109. The time-division selection signal is input via the time-division selection signal line 111. The enable signal is input via the enable signal line HE. In accordance with each of these input signals, the ejection drive element MD1 is selected to conduct and current flows to the ejection heater RhA.

[0093] In the circulating module 105, the circulating group selection signal, the time-division selection signal, and the enable signal are input to the second logic circuit AND2. The circulating group selection signal is output from the control data supply circuit 106 and input via the circulating group selection signal line 110. In response to each of these input signals, the second logic circuit AND2 is selected to conduct and current flows to the corresponding circulating heater RhB.

[0094] Sharing the signal line for transmitting the time-division selection signal in the discharge module 104 and the circulation module 105 contributes to reducing the amount of serial data transferred and reducing the layout area of ​​the signal wiring inside the element substrate 18 (as described later).

[0095] Furthermore, the element substrate 18 has an external input terminal for an enable signal. The enable signal is transmitted from the controller 101. The enable signal controls the pulse width (the time the transistor is turned on and current is flowing) of the discharge drive element MD1 and the circulation drive element MD2 of the selected discharge module 104 and circulation module 105. Due to manufacturing variations in the element substrate 18, variations in heater resistance values, power supply variations, and voltage drops in power supply wiring when multiple heaters are driven simultaneously may occur. The enable signal is used to adjust the current pulse width to generate more desired thermal energy, taking these variations into consideration.

[0096] Furthermore, the clock signal, data signal, and latch signal are transmitted from the controller 101. The clock signal is input via the clock signal line CLK. The clock signal line CLK serially transfers selection information for selecting the discharge module 104 and the circulation module 105 to the first shift register 203a and the second shift register 203b (see Figure 7(a)), respectively. The data signal is input to the control data supply circuit 106 via the data signal line DATA. The latch signal is input to the control data supply circuit 106 via the latch signal line LT. The latch signal line LT holds the selection information.

[0097] Furthermore, the power supply circuit 102 is configured to supply power to the discharge module 104 and the circulation module 105. The element substrate 18 has a ground wire GNDH that receives power supplied from the power supply circuit 102, and a first power supply wire VH. Power is supplied to the discharge module 104 and the circulation module 105, respectively, at a common voltage (for example, 24V) via the first power supply wire VH.

[0098] However, if it is desired to further mitigate fluctuations in discharge energy due to voltage drops when multiple heaters are driven simultaneously, power may be supplied individually from the power supply circuit 102 to the discharge module 104 and the circulation module 105, respectively. In this case, the element board 18 is provided with separate power supply voltage and ground potential supply wiring and external connection terminals for the discharge module 104, and separate power supply voltage and ground potential supply wiring and external connection terminals for the circulation module 105.

[0099] Generally, drive circuits operate at higher voltages than logic circuits. For this reason, substrates are used that contain both high-voltage transistors and ordinary transistors. In this embodiment, the ejection drive element MD1 and the circulation drive element MD2 are composed of high-voltage MOS transistors, specifically DMOS transistors (Double-diffused MOSFETs).

[0100] The drive current of the circulating heater RhB generates thermal energy to circulate the liquid in the individual flow path 23 (see Figure 4(a), etc.). If the drive current of the circulating heater RhB is smaller than the drive current of the discharge heater RhA, the current driving capability of the DMOS transistor may be relatively low. It is preferable that the area of ​​the circulating drive element MD2 is smaller than the area of ​​the discharge drive element MD1.

[0101] Figure 7(a) is a schematic diagram of a control data supply circuit 106 that can be applied to this embodiment.

[0102] As shown in Figure 7(a), the control data supply circuit 106 includes a decoder circuit 205 connected to the time-division selection signal line 111, a first latch circuit 204a connected to the decoder circuit 205, and a first shift register 203a connected to the first latch circuit 204a.

[0103] The control data supply circuit 106 includes a circulating group selection circuit 201 connected to the circulating group selection signal line 110, and a second latch circuit 204b connected to the discharge group selection signal line 109. The control data supply circuit 106 also includes a second shift register 203b connected to the second latch circuit 204b, and external input terminals for inputting a clock signal, a data signal, and a latch signal, respectively.

[0104] In the control data supply circuit 106, the logic circuits are composed of low-voltage MOS transistors. For example, the cyclic group selection circuit 201, the first shift register 203a, the second shift register 203b, the first latch circuit 204a, the second latch circuit 204b, and the decoder circuit 205 are all composed of low-voltage MOS transistors. The first logic circuit AND1 and the second logic circuit AND2 (see Figure 6) are also composed of low-voltage MOS transistors.

[0105] Figure 7(b) is a schematic diagram of a circulating group selection circuit 201 that can be applied to this embodiment.

[0106] As shown in Figure 7(b), the circulation group selection circuit 201 includes a discharge group selection signal line 109 and a circulation group selection signal line 110.

[0107] Figure 8 is a schematic diagram showing the arrangement of elements on a substrate 18 that can be applied to this embodiment.

[0108] As shown in Figure 8, the element substrate 18 includes a plurality of discharge heaters RhA, a plurality of circulation heaters RhB, a plurality of discharge drive elements MD1, and a plurality of circulation drive elements MD2. The plurality of discharge heater rows 112 and the plurality of circulation heater rows 113 are formed along the direction (Y direction) in which the long side of the element substrate 18 extends.

[0109] Specifically, the multiple discharge heaters RhA include the first discharge heater RhA-1, the second discharge heater RhA-2, the third discharge heater RhA-3, and the fourth discharge heater RhA-4. Hereafter, unless there is a need to distinguish between the first discharge heater RhA-1, the second discharge heater RhA-2, the third discharge heater RhA-3, and the fourth discharge heater RhA-4, they will be referred to as discharge heaters RhA.

[0110] Furthermore, the multiple circulating heaters RhB include the first circulating heater RhB-1, the second circulating heater RhB-2, the third circulating heater RhB-3, and the fourth circulating heater RhB-4. Hereafter, unless there is a need to distinguish between the first circulating heater RhB-1, the second circulating heater RhB-2, the third circulating heater RhB-3, and the fourth circulating heater RhB-4, they will be referred to as circulating heaters RhB.

[0111] Multiple discharge drive elements MD1 and multiple circulation drive elements MD2 are arranged alternately along the Y direction. The arrangement of multiple discharge drive elements MD1 and multiple circulation drive elements MD2 alternately in a row along the Y direction forms a drive element row 301.

[0112] The main components of the discharge heater RhA and the circulation heater RhB include a resistive material. For example, the discharge heater RhA and the circulation heater RhB include tantalum silicon nitride or tungsten silicon nitride as the resistive material.

[0113] The ejection drive element MD1 and the circulation drive element MD2 are provided on the same semiconductor layer. Both the ejection drive element MD1 and the circulation drive element MD2 can be N-type field-effect transistors. The arrangement of the multiple ejection heater rows 112 and the multiple circulation heater rows 113 may be reversed from the example shown in Figure 8. That is, two rows of ejection heater rows 112 may be arranged between two rows of circulation heater rows 113.

[0114] Figure 9 is a schematic enlarged view showing a part of the wiring configuration of the element substrate 18.

[0115] As shown in Figure 9, the element substrate 18 comprises a first unit 403-1 including a plurality of electrical components and a second unit 403-2 including a plurality of electrical components.

[0116] The first unit 403-1 includes a first discharge heater RhA-1 that generates energy for discharging liquid, and a first circulation heater RhB-1 that generates energy for circulating liquid. The first unit 403-1 includes a first discharge drive element MD1-1 that drives the first discharge heater RhA-1, and a first circulation drive element MD2-1 that drives the first circulation heater RhB-1. The first unit 403-1 includes a first discharge wiring 107-1 that connects the first discharge heater RhA-1 and the first discharge drive element MD1-1, and a first circulation wiring 108-1 that connects the first circulation heater RhB-1 and the first circulation drive element MD2-1.

[0117] Hereafter, unless there is a need to distinguish between the first discharge wiring 107-1, the second discharge wiring 107-2, the third discharge wiring 107-3, and the fourth discharge wiring 107-4, they will be referred to as discharge wiring 107. Similarly, unless there is a need to distinguish between the first circulation wiring 108-1, the second circulation wiring 108-2, the third circulation wiring 108-3, and the fourth circulation wiring 108-4, they will be referred to as circulation wiring 108.

[0118] The second unit 403-2 includes a second discharge heater RhA-2 for generating energy to discharge liquid and a second circulation heater RhB-2 for generating energy to circulate liquid. The second unit 403-2 includes a second discharge drive element MD1-2 for driving the second discharge heater RhA-2 and a second circulation drive element MD2-2 for driving the second circulation heater RhB-2. The second unit 403-2 includes a second discharge wiring 107-2 connecting the second discharge heater RhA-2 and the second discharge drive element MD1-2, and a second circulation wiring 108-2 connecting the second circulation heater RhB-2 and the second circulation drive element MD2-2.

[0119] The element substrate 18 has a first power supply wiring VH (see Figure 6) that supplies power to the first discharge heater RhA-1, the first circulation heater RhB-1, the second discharge heater RhA-2, and the second circulation heater RhB-2. The first power supply wiring VH includes a first extension portion 402-1 that extends between the first discharge heater RhA-1 and the second discharge heater RhA-2. Hereinafter, unless there is a need to distinguish between the first extension portion 402-1 and the second extension portion 402-2, they will be referred to as extension portion 402.

[0120] The first unit 403-1 and the second unit 403-2 are arranged symmetrically with respect to the first extension 402-1. Specifically, the first extension 402-1 is located on the boundary line between the first unit 403-1 and the second unit 403-2. The first unit 403-1 and the second unit 403-2 are arranged symmetrically with respect to the boundary line between the first unit 403-1 and the second unit 403-2.

[0121] Furthermore, the first power supply wiring VH includes a longitudinal portion 401 that extends along the long side of the element substrate 18. Each of the multiple discharge heaters RhA and the multiple circulation heaters RhB is connected to the longitudinal portion 401 of the first power supply wiring VH, and power is supplied from the first power supply wiring VH.

[0122] Furthermore, the element substrate 18 includes a second power supply wiring 404 that extends along the long side of the element substrate 18. The base end of the first extended portion 402-1 is connected to the longitudinal portion 401. The tip of the first extended portion 402-1 is connected to the second power supply wiring 404 via a conductive plug 405. The main component of the conductive plug 405 includes a metallic material. Examples of materials constituting the conductive plug 405 include tungsten or copper.

[0123] In the orientation in which the liquid discharge head 1 (see Figure 1) is used, the element substrate 18 is constructed in this embodiment by stacking a first layer, an insulating layer, and a second layer in the order from bottom to top along the Z direction. The first and second layers contain metal as their main component. For example, the first and second layers are made of aluminum or copper. The first layer (the innermost layer in Figure 9) is provided with a first extension portion 402-1, a longitudinal portion 401, discharge wiring 107, and circulation wiring 108. The insulating layer is provided with a conductive plug 405. The second layer (the frontmost layer in Figure 9) is provided with a second power supply wiring 404.

[0124] Furthermore, the element substrate 18 comprises a first unit 403-1, a second unit 403-2, a third unit 403-3, and a fourth unit 403-4, which are arranged continuously along the Y direction. The third unit 403-3 and the fourth unit 403-4 include multiple electrical components, similar to the first unit 403-1 and the second unit 403-2.

[0125] The third unit 403-3 includes a third discharge heater RhA-3 that generates energy for discharging liquid, and a third circulation heater RhB-3 that generates energy for circulating liquid. The third unit 403-3 includes a third discharge drive element MD1-3 that drives the third discharge heater RhA-3, and a third circulation drive element MD2-3 that drives the third circulation heater RhB-3. The third unit 403-3 includes a third discharge wiring 107-3 that connects the third discharge heater RhA-3 and the third discharge drive element MD1-3, and a third circulation wiring 108-3 that connects the third circulation heater RhB-3 and the third circulation drive element MD2-3.

[0126] The fourth unit 403-4 includes a fourth discharge heater RhA-4 that generates energy for discharging liquid, and a fourth circulation heater RhB-4 that generates energy for circulating liquid. The fourth unit 403-4 includes a fourth discharge drive element MD1-4 that drives the fourth discharge heater RhA-4, and a fourth circulation drive element MD2-4 that drives the fourth circulation heater RhB-4. The fourth unit 403-4 includes a fourth discharge wiring 107-4 that connects the fourth discharge heater RhA-4 and the fourth discharge drive element MD1-4, and a fourth circulation wiring 108-4 that connects the fourth circulation heater RhB-4 and the fourth circulation drive element MD2-4.

[0127] The element substrate 18 has a first power supply wiring VH (see Figure 6) that supplies power to the third discharge heater RhA-3, the third circulation heater RhB-3, the fourth discharge heater RhA-4, and the fourth circulation heater RhB-4. The first power supply wiring VH includes a second extension portion 402-2 that extends between the third discharge heater RhA-3 and the fourth discharge heater RhA-4.

[0128] The third unit 403-3 and the fourth unit 403-4 are arranged symmetrically with respect to the second extension 402-2. Specifically, the second extension 402-2 is located on the boundary line between the third unit 403-3 and the fourth unit 403-4. The third unit 403-3 and the fourth unit 403-4 are arranged symmetrically with respect to the boundary line between the third unit 403-3 and the fourth unit 403-4.

[0129] The first power wiring VH can supply power to the third discharge heater RhA-3 and the fourth discharge heater RhA-4, respectively, using the longitudinal portion 401 and the portion extending along the direction intersecting the longitudinal portion 401. With the above configuration, it is possible to secure a region between the first discharge heater RhA-1 and the second discharge heater RhA-2 for arranging the first extended portion 402-1, which has a relatively wide width (length in the Y direction).

[0130] Furthermore, a region can be secured between the third discharge heater RhA-3 and the fourth discharge heater RhA-4 for arranging the second extension 402-2, which has a relatively wide width (length in the Y direction).

[0131] Furthermore, the second circulation wiring 108-2 and the third circulation wiring 108-3 must be placed between the second discharge heater RhA-2 and the third discharge heater RhA-3. The width (length in the Y direction) of the second circulation wiring 108-2 and the third circulation wiring 108-3 is narrower than the width (length in the Y direction) of the extended portion 402. For this reason, it is entirely possible to place two circulation wirings 108 between the two discharge heaters RhA. Note that the arrangement of multiple discharge heaters RhA and multiple circulation heaters RhB can be reversed.

[0132] Figure 10 shows a comparative example of the wiring configuration of the element substrate 18 according to this embodiment.

[0133] As shown in Figure 10, the first unit 403-1 and the second unit 403-2 are positioned in the same orientation. Thus, in this comparative example, the first unit 403-1 and the second unit 403-2 are not positioned symmetrically with respect to the first extension 402-1. Furthermore, the third unit 403-3 and the fourth unit 403-4 are also positioned in the same orientation and are not positioned symmetrically with respect to the second extension 402-2.

[0134] Furthermore, in the element substrate 18 of Figure 10, the lengths in the Y direction of two adjacent discharge heaters RhA are different in order to match the size in the Y direction of the element substrate 18 of Figure 9. Of these two types of discharge heaters RhA, the length in the Y direction of one is the same as the length in the Y direction of the discharge heater RhA used in the example of Figure 9, but the length in the Y direction of the other is shorter than the length in the Y direction of the discharge heater RhA used in the example of Figure 9.

[0135] In other words, in this comparative example, if all the discharge heaters RhA were the same size as the discharge heaters RhA in Figure 9, the overall length of the element substrate 18 in the Y direction would become longer. Thus, in this comparative example, it becomes difficult to arrange two discharge heaters RhA with relatively large widths (length in the Y direction) consecutively along the Y direction. Furthermore, when using two types of discharge heaters RhA with different sizes, the heat output of each discharge heater RhA is different, making control complicated.

[0136] Furthermore, this comparative example also makes it difficult to accommodate the requirement of placing multiple relatively thin wires (e.g., discharge wire 107, circulation wire 108, and both of these) between the two discharge heaters RhA.

[0137] In contrast, in the element substrate 18 of this embodiment, the two units are arranged symmetrically. Therefore, space is secured for continuously arranging ejection heaters RhA of the desired size along a predetermined direction. By arranging ejection heaters RhA (recording elements) of the desired size in this secured space, the recording element substrate 3 can be manufactured without increasing the size of the element substrate 18.

[0138] Therefore, according to the technology of this embodiment, it is possible to provide a recording element substrate in which recording elements, circulating elements, and wiring are efficiently arranged.

[0139] [Second Embodiment] In the following description, configurations similar to or corresponding to the first embodiment will be omitted from the explanation, and the differences will be described primarily.

[0140] Figure 11 is a schematic enlarged view showing a portion of the wiring configuration of the element substrate 18 that can be applied to the second embodiment.

[0141] As shown in Figure 11, the element substrate 18 of this embodiment includes a ninth unit 602 which comprises a plurality of units. The ninth unit 602 includes a first unit 403-1, a second unit 403-2, a third unit 403-3, and a fourth unit 403-4.

[0142] In this embodiment, for the sake of explanation, one of the two second supply ports 32 is referred to as the second supply port 32-1, and the other as the second supply port 32-2.

[0143] The second supply port 32-1 is provided so as to straddle the first unit 403-1 and the second unit 403-2. The second supply port 32-1 is located approximately in the center in the X direction of the combined area of ​​the first unit 403-1 and the second unit 403-2. The first discharge wiring 107-1 and the second discharge wiring 107-2 are provided so as to avoid the second supply port 32-1. In the Y direction, the second supply port 32-1 is located between the first discharge wiring 107-1 and the second discharge wiring 107-2.

[0144] The second supply port 32-2 is provided so as to straddle the third unit 403-3 and the fourth unit 403-4. The second supply port 32-2 is located approximately in the center in the X direction of the combined area of ​​the third unit 403-3 and the fourth unit 403-4. The third discharge wiring 107-3 and the fourth discharge wiring 107-4 are provided so as to avoid the second supply port 32-2. In the Y direction, the second supply port 32-2 is located between the third discharge wiring 107-3 and the fourth discharge wiring 107-4.

[0145] This configuration also provides the same effects as the first embodiment.

[0146] [Third Embodiment] In the following description, configurations similar to or corresponding to those in the first and second embodiments will be omitted from the explanation, and the differences will be described primarily.

[0147] Figure 12 is a schematic enlarged view showing a portion of the wiring configuration of the element substrate 18 that can be applied to the third embodiment.

[0148] As shown in Figure 12, the element substrate 18 of this embodiment includes a fifth unit 403-5, a sixth unit 403-6, a seventh unit 403-7, and an eighth unit 403-8. The fifth unit 403-5, the sixth unit 403-6, the seventh unit 403-7, and the eighth unit 403-8 are arranged in this order along the Y direction.

[0149] The fifth unit 403-5 includes a first circulation drive element MD2-1, a first discharge drive element MD1-1, a second circulation drive element MD2-2, and a second discharge drive element MD1-2. The fifth unit 403-5 also includes a first discharge heater RhA-1, a second discharge heater RhA-2, a first circulation heater RhB-1, and a second circulation heater RhB-2.

[0150] The fifth unit 403-5 includes a first circulation wiring 108-1 connecting the first circulation drive element MD2-1 and the first circulation heater RhB-1. The fifth unit 403-5 also includes a first discharge wiring 107-1 connecting the first discharge drive element MD1-1 and the first discharge heater RhA-1.

[0151] The fifth unit 403-5 includes a second circulation wiring 108-2 connecting the second circulation drive element MD2-2 and the second circulation heater RhB-2. The fifth unit 403-5 also includes a second discharge wiring 107-2 connecting the second discharge drive element MD1-2 and the second discharge heater RhA-2.

[0152] The sixth unit 403-6 includes a third discharge drive element MD1-3, a third circulation drive element MD2-3, a fourth discharge drive element MD1-4, and a fourth circulation drive element MD2-4. The sixth unit 403-6 also includes a third discharge heater RhA-3, a fourth discharge heater RhA-4, a third circulation heater RhB-3, and a fourth circulation heater RhB-4.

[0153] The sixth unit 403-6 includes a third discharge wiring 107-3 connecting the third discharge drive element MD1-3 and the third discharge heater RhA-3. The sixth unit 403-6 also includes a third circulation wiring 108-3 connecting the third circulation drive element MD2-3 and the third circulation heater RhB-3.

[0154] The sixth unit 403-6 includes a fourth discharge wiring 107-4 connecting the fourth discharge drive element MD1-4 and the fourth discharge heater RhA-4. The sixth unit 403-6 also includes a fourth circulation wiring 108-4 connecting the fourth circulation drive element MD2-4 and the fourth circulation heater RhB-4.

[0155] The seventh unit 403-7 includes a fifth circulation drive element MD2-5, a fifth discharge drive element MD1-5, a sixth circulation drive element MD2-6, and a sixth discharge drive element MD1-6. The seventh unit 403-7 also includes a fifth discharge heater RhA-5, a sixth discharge heater RhA-6, a fifth circulation heater RhB-5, and a sixth circulation heater RhB-6.

[0156] The seventh unit 403-7 includes a fifth circulation wiring 108-5 connecting the fifth circulation drive element MD2-5 and the fifth circulation heater RhB-5. The seventh unit 403-7 also includes a fifth discharge wiring 107-5 connecting the fifth discharge drive element MD1-5 and the fifth discharge heater RhA-5.

[0157] The seventh unit 403-7 includes a sixth circulation wiring 108-6 connecting the sixth circulation drive element MD2-6 and the sixth circulation heater RhB-6. The seventh unit 403-7 also includes a sixth discharge wiring 107-6 connecting the sixth discharge drive element MD1-6 and the sixth discharge heater RhA-6.

[0158] The eighth unit 403-8 includes the seventh discharge drive element MD1-7, the seventh circulation drive element MD2-7, the eighth discharge drive element MD1-8, and the eighth circulation drive element MD2-8. The eighth unit 403-8 also includes the seventh discharge heater RhA-7, the eighth discharge heater RhA-8, the seventh circulation heater RhB-7, and the eighth circulation heater RhB-8.

[0159] The eighth unit 403-8 includes a seventh discharge wiring 107-7 connecting the seventh discharge drive element MD1-7 and the seventh discharge heater RhA-7. The eighth unit 403-8 also includes a seventh circulation wiring 108-7 connecting the seventh circulation drive element MD2-7 and the seventh circulation heater RhB-7.

[0160] The eighth unit 403-8 includes an eighth discharge wiring 107-8 connecting the eighth discharge drive element MD1-8 and the eighth discharge heater RhA-8. The eighth unit 403-8 also includes an eighth circulation wiring 108-8 connecting the eighth circulation drive element MD2-8 and the eighth circulation heater RhB-8.

[0161] In this embodiment, a third extension 402-3 is provided between the second discharge heater RhA-2 and the third discharge heater RhA-3. Hereinafter, unless there is a need to distinguish between the third extension 402-3 and the fourth extension 402-4, they will be referred to as extension 402.

[0162] The third extension portion 402-3 extends in the X direction along the short side of the element substrate 18. One end of the third extension portion 402-3 is connected to the second power supply wiring 404 via a conductive plug 405. The other end of the third extension portion 402-3 is connected to the longitudinal portion 401 of the first power supply wiring VH.

[0163] Each component constituting the fifth unit 403-5 and each component constituting the sixth unit 403-6 are arranged symmetrically with respect to the third extension 402-3. A fourth extension 402-4 is provided between the sixth discharge heater RhA-6 and the seventh discharge heater RhA-7.

[0164] The fourth extension 402-4 extends in the X direction along the short side of the element substrate 18. One end of the fourth extension 402-4 is connected to the second power wiring 404 via a conductive plug 405. The other end of the fourth extension 402-4 is connected to the longitudinal portion 401 of the first power wiring VH. The members constituting the seventh unit 403-7 and the members constituting the eighth unit 403-8 are arranged symmetrically with respect to the fourth extension 402-4. The main components of the third extension 402-3 and the fourth extension 402-4 include a metallic material (e.g., aluminum or copper).

[0165] This configuration also provides the same effects as the first embodiment.

[0166] In this embodiment, each unit is equipped with two discharge heaters, two circulation heaters, and two of each of the two types of drain wiring, but the number of these may be three or more.

[0167] [Fourth Embodiment] In the following description, configurations similar to or corresponding to those in the first to third embodiments will be omitted from the explanation, and the differences will be described primarily.

[0168] Figure 13 is a schematic enlarged view showing a portion of the wiring configuration of the element substrate 18 that can be applied to the fourth embodiment.

[0169] As shown in Figure 13, in this embodiment, a second supply port 32-1 is formed in the element substrate 18 between the second discharge wiring 107-2 and the third discharge wiring 107-3. Furthermore, a second supply port 32-2 is formed between the sixth discharge wiring 107-6 and the seventh discharge wiring 107-7.

[0170] This configuration also provides the same effects as the first embodiment.

[0171] [Fifth Embodiment] In the following description, configurations similar to or corresponding to the first to fourth embodiments will be omitted from the explanation, and the differences will be described primarily.

[0172] Figure 14 is a schematic enlarged view showing a portion of the wiring configuration of the element substrate 18 that can be applied to the fifth embodiment.

[0173] As shown in Figure 14, the element substrate 18 of this embodiment comprises a tenth unit 902 which includes two ninth units 602. For the sake of explanation, one of the two ninth units 602 will be referred to as "ninth unit 602L" and the other as "ninth unit 602R".

[0174] In the element substrate 18 of this embodiment, a plurality of supply ports 901 (four in this embodiment) for supplying liquid to the ninth unit 602 are formed in the center of the direction in which the short side extends (X direction) and along the direction in which the long side extends (Y direction).

[0175] For the sake of explanation, in the following description, with the element substrate 18 viewed from above, the four supply ports 901 will be referred to as "supply port 901-1," "supply port 901-2," "supply port 901-3," and "supply port 901-4," respectively. Each of the supply ports 901-1, 901-2, 901-3, and 901-4 supplies liquid to the ninth unit 602L and the ninth unit 602R, respectively.

[0176] This configuration allows liquid to be supplied to the ninth unit 602L and the ninth unit 602R using a single row of supply ports, which consists of multiple supply ports formed along the Y direction.

[0177] Therefore, compared to a configuration in which two supply port rows are formed along the X direction, one for supplying liquid only to the ninth unit 602L and the other for supplying liquid only to the ninth unit 602R, the element substrate 18 can be miniaturized in the X direction.

[0178] Furthermore, the ninth unit 602L and the ninth unit 602R are arranged symmetrically with respect to the center point 180 of the tenth unit 902. Note that the center point 180 in Figure 14 is a virtual point. With this configuration, the heat generation on the element substrate 18 can be balanced between the left and right sides.

[0179] Therefore, according to the recording element substrate of this embodiment, the recording elements, circulation elements, and wiring can be efficiently arranged while balancing heat generation.

[0180] [Sixth Embodiment] In the following description, configurations similar to or corresponding to those in the first to fifth embodiments will be omitted from the explanation, and the differences will be described primarily.

[0181] Figure 15 is a schematic enlarged view showing a portion of the wiring configuration of the element substrate 18 that can be applied to the sixth embodiment.

[0182] As shown in Figure 15, in the element substrate 18 of this embodiment, two 10th units 902 are arranged along the X direction. Alternatively, three or more 10th units 902 may be arranged along the X direction.

[0183] This configuration also provides the same effects as the fifth embodiment.

[0184] [Seventh Embodiment] In the following description, configurations similar to or corresponding to those in the first to sixth embodiments will be omitted from the explanation, and the differences will be described primarily.

[0185] Figure 16(a) is a plan view showing the configuration of the flow path in the recording element substrate 3 that can be applied to this embodiment along the direction in which the droplets are ejected.

[0186] Figure 16(b) is a cross-sectional view taken along the line XVIb-XVIb in Figure 16(a). As shown in Figure 16(b), in this embodiment as well, straight individual channels 23 are formed. In the example of Figure 3(b), channels extending parallel to the Z direction were formed in the element substrate 18. However, as shown in Figure 16(b), channels that spread away from the discharge port 11 may be formed in the element substrate 18. This configuration also provides the same effects as the first embodiment.

[0187] [Eighth Embodiment] In the following description, configurations similar to or corresponding to those in Embodiments 1 to 7 will be omitted from the explanation, and the differences will be described primarily.

[0188] Figure 17(a) is a schematic plan view showing the configuration of the flow path in the recording element substrate 3, which can be applied to this embodiment along the direction in which the droplets are ejected.

[0189] As shown in Figure 17(a), in this embodiment, a plurality of first supply ports 22 are formed along the X direction. In this embodiment, three first supply ports 22 are formed along the X direction, but four or more first supply ports 22 may be formed.

[0190] Furthermore, multiple discharge ports 11 are formed along the X direction. And multiple rows of discharge ports extending in the Y direction are formed along the X direction. Thus, in this embodiment, compared to the first embodiment, the number of first supply ports 22 and the number of discharge ports 11 in the X direction are increased in the X direction.

[0191] In this embodiment, each of the two discharge ports 11 arranged in the X direction is offset in the Y direction. By offsetting each discharge port 11 in each row of discharge ports in the Y direction in this way, the recording resolution can be improved compared to the case shown in Figure 2(b) where each discharge port 11 in each row of discharge ports is aligned in the Y direction. However, it is not necessary to offset each of these discharge ports 11 in the Y direction.

[0192] Furthermore, no wiring is provided between each supply port at the center in the X direction. This configuration offers greater flexibility in the size of the first supply port 22 located at the center in the X direction compared to a configuration in which wiring is provided between each supply port at the center in the X direction.

[0193] Furthermore, the two discharge ports 11, located in the X direction, are positioned relatively close to the first supply port 22, which is located in the center of the X direction. This configuration eliminates the need for wiring areas between the openings of the central row of ink supply ports, allowing for greater flexibility in the size and resolution of the openings in the central row of ink supply ports. Compared to a configuration where the discharge ports 11 are formed relatively far from the first supply port 22, this configuration allows for faster liquid refilling to the discharge ports 11 and improves recording productivity.

[0194] In the present embodiment, the positions of the three first supply ports 22 formed along the X direction in the Y direction are aligned. However, the positions of the three first supply ports 22 in the Y direction may be shifted in accordance with the position of the discharge port 11, the layout of the wiring, or both of them.

[0195] FIG. 17(b) is a cross-sectional view taken along line XVII-XVII in FIG. 17(a).

[0196] As shown in FIG. 17(b), on the element substrate 18 of the present embodiment, flow paths are formed so as to extend away from the two discharge ports 11 formed along the X direction in the -Z direction.

[0197] As described above, according to the configuration of the present embodiment, compared with the first embodiment (a configuration in which the configuration shown in FIG. 3 is arranged in two rows in the X direction), the size in the X direction can be reduced. Furthermore, the degree of freedom in design can also be improved.

[0198] FIG. 17(c) is a diagram showing a modified example of a flow path applicable to the present embodiment.

[0199] In FIG. 17(b), the flow paths of the element substrate 18 extend away from the discharge ports 11. However, as shown in FIG. 17(c), all of the plurality of flow paths formed in the element substrate 18 may extend straight along the Z direction. Even with such a configuration, the same effects as the configuration of FIG. 17(b) can be obtained.

[0200] [Embodiment 9] <U-shaped> In the following description, for the same or corresponding configurations as those in the first to eighth embodiments, the description will be omitted, and the different points will be mainly described.

[0201] In the above embodiment, the straight type individual flow path 23 (see FIG. 3(a) etc.) was used. However, a U-shaped flow path may be used. Hereinafter, the liquid discharge head 1 (see FIG. 1) provided with the U-shaped individual flow path 23 will be described.

[0202] Figures 18(a) to 18(c) are schematic diagrams illustrating the configuration of the flow channels in the recording element substrate 3 applicable to this embodiment. Figure 18(a) is a schematic plan view of the vicinity of the discharge port 11, Figure 18(b) is a cross-sectional view of Figure 18(a), and Figure 18(c) is an enlarged view focusing on one of the flow channels in Figure 18(a).

[0203] As shown in Figure 18(a), in a plan view of the recording element substrate 3 of this embodiment, U-shaped individual channels 23 are formed on the recording element substrate 3.

[0204] In this disclosure, "U-shaped" means that the shape of the flow path having the discharge heater RhA and the circulation heater RhB is U-shaped.

[0205] In this embodiment, multiple U-shaped individual flow channels 23 are formed along the Y direction. In the U-shaped individual flow channels 23, the discharge heater RhA and the circulation heater RhB are arranged along the Y direction. Therefore, in this embodiment, the discharge heater RhA and the circulation heater RhB are arranged alternately along the direction in which the row of discharge ports extends.

[0206] In the U-shaped individual channel 23, the end where the circulating flow 27 turns back is located outside the row of discharge ports. In the individual channel 23, the circulating flow 27 passes through the section where the circulating heater RhB is provided, then turns back at the end of the individual channel 23 and passes through the section where the discharge heater RhA is provided.

[0207] Furthermore, in this embodiment, a supply groove 42 is formed in the center of the recording element substrate 3 in the X direction, extending along the Y direction and supplying liquid from the element substrate 18 to the discharge port forming member 19. Two rows of discharge ports are formed on the discharge port forming member 19, extending along the Y direction in addition to the X direction. When the recording element substrate 3 is viewed from above, one of the two rows of discharge ports is formed to the left of the supply groove 42, and the other is formed to the right of the supply groove 42. In this way, in this embodiment, liquid is supplied from the supply groove 42 to each of the individual flow paths 23 formed on both sides thereof.

[0208] Furthermore, in the recording element substrate 3, multiple individual channels 23 are arranged along the Y direction. In these U-shaped individual channels 23, the ends where the circulating flow 27 folds back are adjacent to each other along the Y direction.

[0209] As shown in Figure 18(b), with the element substrate 18 and the discharge port forming member 19 bonded together, the supply groove 42 is formed to penetrate the element substrate 18 in the Z direction. The supply groove 42 gradually narrows in diameter in the direction in which the liquid is supplied (Z direction). This configuration ensures the flow velocity when supplying liquid. However, this configuration is not essential.

[0210] When liquid is discharged from the discharge port 11, the liquid is supplied from a supply groove 42 formed in the center of the element substrate 18 in the X direction. Individual flow channels 23, which function as a pressure chamber 12, are formed in the discharge port forming member 19 so as to extend outward from the portion to which liquid is supplied from the supply groove 42. When the liquid is circulated, a flow occurs in the pressure chamber 12 from both ends in the X direction toward the center and a flow toward the outside. In this way, both liquid inflow and outflow occur in common at the center of the supply groove 42.

[0211] In this embodiment, one supply groove 42 is formed, but as in the first embodiment, multiple first supply ports 22 (see Figure 3(a), etc.) may be formed. In this case, the first supply ports 22 are shared within the element substrate 18, similar to the first embodiment. Even with such a configuration, it is possible to form U-shaped individual flow channels 23.

[0212] According to this embodiment, since the discharge heater RhA and the circulation heater RhB can be arranged in a single row along the Y direction, the width of the recording element substrate in the X direction can be shortened compared to a straight type.

[0213] [Tenth Embodiment] In the following description, configurations similar to or corresponding to those in the first to ninth embodiments will be omitted from the explanation, and the differences will be the main focus of the description.

[0214] Figures 19(a) and 19(b) show examples of recording element substrates 3 that can be applied to this embodiment.

[0215] In the first embodiment, one recording element substrate 3 was attached to the liquid discharge head 1 (see Figure 2). Four types of liquids were discharged from this single recording element substrate 3. However, multiple recording element substrates 3 may be attached to the liquid discharge head 1. For example, as shown in Figure 19(a), if the recording element substrate 3 is configured to discharge two types of liquids, two recording element substrates 3 may be attached to the liquid discharge head 1. The same effects as in the first embodiment can be obtained with such a configuration.

[0216] Furthermore, the same effects as in the first embodiment can be obtained by using the recording element substrate 3 of the first embodiment, a liquid ejection head 1 equipped with one of the recording element substrates 3 of this embodiment, and a liquid ejection head 1 equipped with the other. In other words, two liquid ejection heads 1 may be used.

[0217] Furthermore, as shown in Figure 19(b), if the recording element substrate 3 is configured to dispense one type of liquid, four recording element substrates 3 may be attached to the liquid dispensing head 1. The same effects as in the first embodiment can be obtained with such a configuration.

[0218] Furthermore, the same effects as in the first embodiment can be obtained by using four liquid discharge heads 1, each equipped with one of the four recording element substrates 3.

[0219] In the examples shown in Figures 19(a) and 19(b), the lengths (lengths in the Y direction) of the multiple recording element substrates 3 were all the same. However, the lengths of each of these recording element substrates 3 may be different.

[0220] [Embodiment 11] In the following description, configurations similar to or corresponding to those in the first to ten embodiments will be omitted from the explanation, and the differences will be the main focus of the description. Figure 20 is a schematic perspective view showing an example of a liquid dispensing device 50 that can be applied to this embodiment.

[0221] In the first embodiment, the liquid was supplied from a main tank 2 (see Figure 1) to a sub-tank 54. However, the technology of this disclosure can be applied even if a main tank 2 is not provided.

[0222] As shown in Figure 20, the liquid ejection device 50 of this embodiment includes an ink cartridge that is detachably attached to the liquid ejection head 1.

[0223] With this configuration, after the liquid inside the ink cartridge is used up, it is possible to dispense the liquid again by replacing it with a new ink cartridge. Furthermore, a head cartridge, which integrates the liquid dispensing head 1 and the ink cartridge, may be detachably mounted on the carriage 60. This configuration also provides the same effects as the first embodiment.

[0224] [Twelfth Embodiment] In the following description, configurations similar to or corresponding to those in the first to eleventh embodiments will be omitted from the explanation, and the differences will be described primarily.

[0225] Figure 21 is a schematic cross-sectional view illustrating the configuration of the flow channels in the recording element substrate 3 to which this embodiment can be applied. Figure 21 shows another example of the cross-sectional view along line IIIb-IIIb in Figure 3(a).

[0226] In the element substrate 18 of the first embodiment, the flow channels located upstream of the first supply port 22 and downstream of the second supply port 32 were shared as a common flow channel 24. However, the flow channels located upstream of the first supply port 22 and the flow channels located downstream of the second supply port 32 may be formed individually. For example, as shown in Figure 21, the element substrate 18 of this embodiment has a first substrate flow channel 221 for supplying liquid to the first supply port 22, and a second substrate flow channel 222 for recovering the liquid supplied from the second supply port 32. The same effects as in the first embodiment can be obtained with such a configuration.

[0227] [Other embodiments] The first to twelfth embodiments have been described above. However, the values, forms, and numbers to which the technology of this disclosure can be applied are not limited to the examples described above, and the values, forms, and numbers described above may be changed as appropriate depending on the configuration of the recording element substrate.

[0228] The number of nozzles forming one nozzle row is not limited to the number exemplified, and may be much larger, such as 512. Also, in the example above, two rows of nozzles capable of dispensing one type of liquid were formed. However, the number of nozzle rows capable of dispensing one type of liquid may be one row, or three or more rows.

[0229] Furthermore, the devices to which the technology of this disclosure can be applied are not limited to serial-type liquid dispensing devices. For example, the technology of this disclosure can also be applied to a page-wide type liquid dispensing device that uses a line head (page-wide head) that is long in the page width direction (X direction) of the recording medium P and records by dispensing liquid onto the recording medium P as it is transported in the transport direction.

[0230] In the embodiments described above, ink was used as the liquid, but the liquids that can be used in the technology of this disclosure are not limited to ink. In addition to ink, various recording liquids can be used as liquids, including processing liquids used to improve the fixation of ink on the recording medium, reduce gloss unevenness, and improve scratch resistance.

[0231] This disclosure includes the following components:

[0232] [Configuration 1] A first unit including a first element and a second element, A second unit including a third element and a fourth element, A power supply wiring including a first part that supplies power to the first unit and a second part that supplies power to the second unit, Equipped with, The power wiring includes an extended portion that extends along the boundary line between the first unit and the second unit. The first element and the third element are arranged symmetrically with respect to the extended portion. The second and fourth elements are arranged symmetrically with respect to the extended portion. The first and second portions are arranged symmetrically with respect to the extending portion. A recording element substrate characterized by the following features.

[0233] [Configuration 2] The first element and the second element differ in size. The third element and the fourth element differ in size. The first element and the third element are of the same size. The second and fourth elements mentioned above are of the same size. A recording element substrate as described in Configuration 1.

[0234] [Configuration 3] The first element and the third element are arranged along a first direction intersecting the extending portion, forming a first element row. The second element and the fourth element are arranged along the first direction and form a second element row. A recording element substrate as described in configuration 1 or 2.

[0235] [Structure 4] The first and third elements are dispensing elements for dispensing liquid. The first unit is, A first discharge drive element that drives the first element, A first discharge wiring that connects the aforementioned first element and the aforementioned first discharge drive element, It further includes, The aforementioned second unit is, A second discharge drive element that drives the third element, A second discharge wiring that connects the aforementioned third element and the aforementioned second discharge drive element, It further includes, The first discharge drive element and the second discharge drive element are arranged symmetrically with respect to the boundary line. The first discharge wiring and the second discharge wiring are arranged symmetrically with respect to the boundary line. A recording element substrate as described in any one of configurations 1 to 3.

[0236] [Composition 5] The second and fourth elements are circulation elements for circulating the liquid. The first unit is, A first circulating drive element that drives the second element, The system further includes a first circulating wiring that connects the second element and the first circulating drive element, The aforementioned second unit is, A second circulating drive element that drives the fourth element, The system further includes a second circulating wiring connecting the fourth element and the second circulating drive element, The first circulating drive element and the second circulating drive element are arranged symmetrically with respect to the boundary line. The first circular wiring and the second circular wiring are arranged symmetrically with respect to the boundary line. The recording element substrate described in Configuration 4.

[0237] [Composition 6] The first element is positioned closer to the first discharge drive element and the first circulation drive element than the second element. The recording element substrate described in Configuration 5.

[0238] [Composition 7] The system further comprises a first supply port that supplies liquid to a first flow path for supplying liquid to the first element and the second element, and a second flow path for supplying liquid to the third element and the fourth element, The first supply port is provided between the first discharge wiring and the second discharge wiring in a first direction intersecting the extended portion. A recording element substrate as described in any one of items 4 to 6 of the configuration.

[0239] [Structure 8] The first supply port is provided in multiple locations along the first direction. The recording element substrate described in Configuration 7.

[0240] [Composition 9] The first supply port is provided so as to straddle the first unit and the second unit. The first supply port is located in the center of the area encompassing the first unit and the second unit. The recording element substrate described in configuration 8.

[0241] [Configuration 10] No first circular wiring is provided between the second element and the fourth element. No first discharge wiring is provided between the first element and the third element. A recording element substrate as described in any one of items 5 to 9 of the configuration.

[0242] [Composition 11] A third unit including a fifth element and a sixth element, A fourth unit including a seventh element and an eighth element, A second power supply wiring including a third part that supplies power to the third unit and a fourth part that supplies power to the fourth unit, Furthermore, The second power supply wiring is, Including a second extending portion that extends along the second boundary line between the third unit and the fourth unit, The fifth element and the seventh element are arranged symmetrically with respect to the second extending portion. The sixth element and the eighth element are arranged symmetrically with respect to the second extending portion. The unit comprising the first unit and the second unit, and the unit comprising the third unit and the fourth unit, are arranged symmetrically with respect to a third boundary line between the second unit and the third unit. A recording element substrate as described in any one of items 7 to 11 of the configuration.

[0243] [Composition 12] The fifth and seventh elements described above are dispensing elements for dispensing liquid. The sixth and eighth elements are circulation elements for circulating the liquid. A recording element substrate as described in configuration 11.

[0244] [Composition 13] The first supply port is provided in multiple locations along the first direction. A recording element substrate as described in configuration 11 or 12.

[0245] [Composition 14] A third unit including a fifth element and a sixth element, A fourth unit including a seventh element and an eighth element, A second power supply wiring including a third part that supplies power to the third unit and a fourth part that supplies power to the fourth unit, Furthermore, The second power supply wiring is, including a second extending portion extending along a second boundary line between the third unit and the fourth unit, the fifth element and the seventh element are symmetrically arranged with respect to the second extending portion, the sixth element and the eighth element are symmetrically arranged with respect to the second extending portion, the third portion and the fourth portion are symmetrically arranged with respect to the second extending portion, a fifth unit including the first unit and the second unit, and a sixth unit including the third unit and the fourth unit are symmetrically arranged with respect to a predetermined point, The recording element substrate according to any one of Configurations 7 to 14.

[0246] [Configuration 15] Two units including the first unit, the second unit, the third unit, and the fourth unit are symmetrically arranged with respect to a predetermined point, The recording element substrate according to Configuration 14.

[0247] [Configuration 16] The recording element substrate further includes a second supply port different from the first supply port that supplies liquid in common to a first flow path in which the first element and the second element are arranged and a second flow path in which the third element and the fourth element are arranged. The first element and the second element are arranged between the first supply port and the second supply port in a direction in which the boundary line extends. The recording element substrate according to Configuration 14 or 15.

[0248] [Configuration 17] A plurality of the second supply ports are provided along the first direction. The recording element substrate according to Configuration 16.

[0249] [Configuration 18] Note that the recording element substrate further includes a discharge port forming member in which a discharge port for discharging liquid is formed by driving the first element and the third element. A recording element substrate as described in any one of configurations 1 to 17.

[0250] [Composition 19] The material constituting the recording element substrate is A first layer containing metal, A second layer containing metal, including, A recording element substrate as described in any one of configurations 1 to 18.

[0251] [Configuration 20] At least one of the first layer and the second layer includes aluminum. Recording element substrate as described in configuration 19.

[0252] [Composition 21] At least one of the first layer and the second layer contains copper. Recording element substrate as described in configuration 19.

[0253] [Composition 22] The system further includes a power supply wiring that supplies power to the aforementioned power supply wiring, The power supply wiring is provided in the first layer, The power supply wiring is provided in the second layer, Recording element substrate as described in configuration 19.

[0254] [Composition 23] A recording element substrate as described in any one of configurations 1 to 22, A tank for storing liquid to be supplied to the recording element substrate, A liquid dispensing head characterized by having the following features.

[0255] [Composition 24] The liquid discharge head described in configuration 23, A transport means for transporting a recording medium, A liquid dispensing device characterized by comprising the following features.

Claims

1. A first unit including a first element and a second element, A second unit including a third element and a fourth element, A power supply wiring including a first part that supplies power to the first unit and a second part that supplies power to the second unit, Equipped with, The power wiring includes an extended portion that extends along the boundary line between the first unit and the second unit. The first element and the third element are arranged symmetrically with respect to the extended portion. The second and fourth elements are arranged symmetrically with respect to the extended portion. The first and second portions are arranged symmetrically with respect to the extending portion. A recording element substrate characterized by the following features.

2. The first element and the second element differ in size. The third element and the fourth element differ in size. The first element and the third element are of the same size. The second element and the fourth element are of the same size. A recording element substrate according to claim 1.

3. The first element and the third element are arranged along a first direction intersecting the extended portion, forming a first element row. The second element and the fourth element are arranged along the first direction and form a second element row. A recording element substrate according to claim 1.

4. The first element and the third element are dispensing elements for dispensing liquid. The first unit is, A first discharge drive element that drives the first element, A first discharge wiring that connects the first element and the first discharge drive element, It further includes, The second unit is, A second discharge drive element that drives the third element, A second discharge wiring that connects the third element and the second discharge drive element, It further includes, The first discharge drive element and the second discharge drive element are arranged symmetrically with respect to the boundary line. The first discharge wiring and the second discharge wiring are arranged symmetrically with respect to the boundary line. A recording element substrate according to claim 1.

5. The second and fourth elements are circulating elements for circulating the liquid. The first unit is, A first circulating drive element that drives the second element, The system further includes a first circulating wiring that connects the second element and the first circulating drive element. The second unit is, A second circulating drive element that drives the fourth element, The system further includes a second circulating wiring connecting the fourth element and the second circulating drive element, The first circulating drive element and the second circulating drive element are arranged symmetrically with respect to the boundary line. The first circular wiring and the second circular wiring are arranged symmetrically with respect to the boundary line. A recording element substrate according to claim 4.

6. The first element is positioned closer to the first discharge drive element and the first circulation drive element than the second element. A recording element substrate according to claim 5.

7. The system further includes a first supply port that supplies liquid to both the first flow path that supplies liquid to the first element and the second element, and the second flow path that supplies liquid to the third element and the fourth element, The first supply port is provided between the first discharge wiring and the second discharge wiring in a first direction intersecting the boundary line. A recording element substrate according to claim 4.

8. The first supply port is provided in multiple locations along the first direction. A recording element substrate according to claim 7.

9. The first supply port is provided so as to straddle the first unit and the second unit. The first supply port is located in the center of the area encompassing the first unit and the second unit. A recording element substrate according to claim 8.

10. No first circular wiring is provided between the second element and the fourth element. The first discharge wiring is not provided between the first element and the third element. A recording element substrate according to claim 5.

11. A third unit including a fifth element and a sixth element, A fourth unit including a seventh element and an eighth element, A second power supply wiring including a third part that supplies power to the third unit and a fourth part that supplies power to the fourth unit, Furthermore, The second power supply wiring is, Including a second extending portion that extends along the second boundary line between the third unit and the fourth unit, The fifth element and the seventh element are arranged symmetrically with respect to the second extending portion. The sixth element and the eighth element are arranged symmetrically with respect to the second extending portion. The unit comprising the first unit and the second unit, and the unit comprising the third unit and the fourth unit, are arranged symmetrically with respect to a third boundary line between the second unit and the third unit. A recording element substrate according to claim 7.

12. The fifth element and the seventh element are dispensing elements for dispensing liquid. The sixth and eighth elements are circulating elements for circulating the liquid. The recording element substrate according to claim 11.

13. The first supply port is provided in multiple locations along the first direction. The recording element substrate according to claim 11.

14. A third unit including a fifth element and a sixth element, A fourth unit including a seventh element and an eighth element, A second power supply wiring including a third part that supplies power to the third unit and a fourth part that supplies power to the fourth unit, Furthermore, The second power supply wiring is, Including a second extending portion that extends along the second boundary line between the third unit and the fourth unit, The fifth element and the seventh element are arranged symmetrically with respect to the second extending portion. The sixth and eighth elements are arranged symmetrically with respect to the second extending portion. The third and fourth portions are arranged symmetrically with respect to the second extending portion. A fifth unit including the first unit and the second unit, and a sixth unit including the third unit and the fourth unit, are arranged symmetrically with respect to a predetermined point. A recording element substrate according to claim 7.

15. Two units, including the first unit, the second unit, the third unit, and the fourth unit, are arranged symmetrically with respect to a predetermined point. A recording element substrate according to claim 14.

16. The recording element substrate further includes a second supply port, different from the first supply port, which supplies liquid to a first flow path in which the first element and the second element are arranged, and to a second flow path in which the third element and the fourth element are arranged. The first element and the second element are arranged between the first supply port and the second supply port in the direction in which the boundary line extends. A recording element substrate according to claim 14.

17. The second supply port is provided in multiple locations along the first direction. A recording element substrate according to claim 16.

18. The device further comprises a discharge port forming member, which has a discharge port formed thereon from which liquid is discharged by driving the first element and the third element. A recording element substrate according to claim 1.

19. The material constituting the recording element substrate is A first layer containing metal, A second layer containing metal, including, A recording element substrate according to claim 1.

20. At least one of the first layer and the second layer contains aluminum. A recording element substrate according to claim 19.

21. At least one of the first layer and the second layer contains copper. A recording element substrate according to claim 19.

22. The system further includes a power supply wiring that supplies power to the aforementioned power supply wiring, The power supply wiring is provided in the first layer, The power supply wiring is provided in the second layer. A recording element substrate according to claim 15.

23. A recording element substrate according to claim 1, A tank for storing liquid to be supplied to the recording element substrate, A liquid dispensing head characterized by having the following features.

24. The liquid dispensing head according to claim 23, A transport means for transporting a recording medium, A liquid dispensing device characterized by comprising the following features.

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