Liquid discharge head, liquid discharge unit, and liquid discharge device

Abstract

The present invention provides a liquid ejection head that can suppress fluctuations in ink placement due to airflow effects, regardless of the transport direction of the print head. [Solution] A liquid discharge head 11 is provided with a nozzle substrate 20A on which a plurality of nozzles 19 are formed, which discharges droplets onto a recording medium being transported in the sub-scanning direction from the nozzles 19, and which is movable in the main scanning direction perpendicular to the sub-scanning direction, wherein the nozzle substrate 20A has a plurality of nozzle rows A, B, C, D formed in the main scanning direction, each consisting of a plurality of nozzles 19 arranged in parallel in the sub-scanning direction, and the density of nozzles 19 forming the outer nozzle rows A, D, which are nozzle rows located outside the nozzle substrate 20A in the main scanning direction, is lower than the density of nozzles 19 forming the inner nozzle rows B, C, which are nozzle rows located inside the nozzle substrate in the main scanning direction.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head, a liquid ejection unit, and a liquid ejection device.

Background Art

[0002] Conventionally, an inkjet liquid ejection device including a liquid ejection head for ejecting a liquid is known. The liquid ejection head includes a nozzle substrate on which a plurality of nozzles for ejecting a liquid are arranged, a valve member for opening and closing the nozzles, and an actuator having a displacement mechanism for displacing the valve member between a nozzle open position and a nozzle closed position, and the actuator is operated to eject the liquid from the nozzles. As an image forming method using this liquid ejection head, there are known a single-pass method in which an image is formed by conveying a recording medium with respect to a fixed head, and a multi-pass method in which the recording medium is conveyed and the head is moved in a direction orthogonal to the conveying direction of the recording medium to form an image.

[0003] In the above-described multi-pass method, as shown in FIG. 3(a), in order to form an image while reciprocating the head in the main scanning direction orthogonal to the sub-scanning direction with respect to the recording medium conveyed in the sub-scanning direction, a high-density and high-quality image can be formed, and it is mainly suitable for forming high-quality images such as photographic images. In such a multi-pass liquid ejection head, as shown in FIGS. 3(b) and (c), due to the influence of the air flow generated by the reciprocating movement of the head and the air flow generated by the ejection of the liquid, the ejected liquid is washed away from the normal landing position, resulting in density unevenness and streaks, and there is a problem that the image quality deteriorates.

[0004] To solve the above-mentioned problems, a technology is known that includes a control means for controlling the amount of ink ejected from the downstream nozzle row to the recording medium based on the ejection density of the ink ejected from the upstream nozzle row to the recording medium (see, for example, "Patent Document 1"). The control means controls the amount of ink ejected by the downstream nozzle row based on the degree of wraparound airflow, which is calculated based on the ejection density and indicates the degree to which wraparound airflow occurs when the transport airflow of the recording medium bypasses the self-airflow of the ink ejected from the upstream nozzle row. [Overview of the project] [Problems that the invention aims to solve]

[0005] The aforementioned technology requires the implementation of a system that determines the ink ejection amount of the downstream nozzle row based on the ejection amount of the upstream nozzle row. Furthermore, when image formation is performed using a multi-pass method, the control direction differs between the forward and return paths, resulting in a problem where the control mechanism of the liquid ejection head becomes extremely complex. The present invention aims to solve the above-mentioned problems and provide a liquid ejection head that can suppress fluctuations in ink landing position due to the influence of airflow, regardless of the transport direction of the head. [Means for solving the problem]

[0006] The invention described in claim 1 comprises a nozzle substrate on which a plurality of nozzles are formed, which discharges droplets onto a recording medium to be transported in the sub-scanning direction from the nozzles, which is movable in the main scanning direction perpendicular to the sub-scanning direction, wherein a plurality of nozzle rows, each consisting of a plurality of nozzles arranged in parallel in the sub-scanning direction, are formed on the nozzle substrate in the main scanning direction, and the density of the nozzles forming the outer nozzle row, which is the nozzle row positioned outside the nozzle substrate in the main scanning direction, is lower than the density of the nozzles forming the inner nozzle row, which is the nozzle row positioned inside the nozzle substrate in the main scanning direction. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a liquid ejection head that can suppress fluctuations in the ink landing position due to the influence of airflow, regardless of the transport direction of the head. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic cross-sectional view of a liquid dispensing head to which one embodiment of the present invention can be applied. [Figure 2] This is a schematic diagram illustrating a nozzle array formed on a conventional nozzle substrate. [Figure 3] This is a schematic diagram illustrating the problems with the conventional configuration. [Figure 4] This is a schematic diagram illustrating the problems with the conventional configuration. [Figure 5] This is a schematic diagram showing the arrangement of nozzles formed on the nozzle substrate of a liquid discharge head according to the first embodiment of the present invention. [Figure 6] This is a schematic diagram showing the arrangement of nozzles formed on the nozzle substrate of a liquid discharge head according to a second embodiment of the present invention. [Figure 7] This is a schematic diagram showing the nozzle substrate of a liquid discharge head according to a third embodiment of the present invention. [Figure 8] This is a schematic diagram showing the arrangement of nozzles formed on the nozzle substrate of a liquid discharge head according to a fourth embodiment of the present invention. [Figure 9] This is a schematic diagram showing the arrangement of nozzles formed on the nozzle substrate of a liquid discharge head according to a fifth embodiment of the present invention. [Figure 10] A schematic front view showing an example of a liquid dispensing device equipped with a liquid dispensing head according to each embodiment of the present invention. [Figure 11] The latest version of the "Hypothetical Head" (Hypothetical Head) is available for use in the "Hypothetical Head" (Hypothetical Head) project. [Figure 12] This is a schematic plan view of another liquid dispensing device equipped with a liquid dispensing head according to each embodiment of the present invention. [Figure 13] This is a schematic side view of another liquid dispensing device equipped with a liquid dispensing head according to each embodiment of the present invention. [Figure 14] This is a schematic plan view illustrating a unit of another device equipped with a head according to each embodiment of the present invention. [Figure 15] This is a schematic front view illustrating another liquid dispensing unit of yet another liquid dispensing device equipped with a liquid droplet dispensing head according to each embodiment of the present invention. [Figure 16] A schematic front view of an electrode manufacturing apparatus, which is yet another liquid dispensing apparatus equipped with a liquid dispensing head according to each embodiment of the present invention. [Modes for carrying out the invention]

[0009] Figure 1 shows a schematic cross-sectional view of a liquid dispensing unit 10 to which one embodiment of the present invention can be applied, along the short-side direction of the liquid dispensing head. In the figure, the liquid dispensing unit 10 comprises a plurality of liquid dispensing heads 11 for dispensing liquid, a base member 12 for holding the plurality of liquid dispensing heads 11, and a cover member 13 which serves as a nozzle cover for the liquid dispensing heads 11. Furthermore, the liquid dispensing unit 10 comprises a manifold 14 that forms a flow path for supplying liquid to the plurality of liquid dispensing heads 11, a printed circuit board (PCB) 17 connected to a flexible wiring member 16 equipped with a driver IC 15 which is a drive circuit, and a module case 18.

[0010] Each of the multiple liquid discharge heads 11 includes a nozzle substrate 20 on which a nozzle 19 is formed, a flow path substrate 22 on which individual liquid chambers 21 which are pressure chambers leading to the nozzle 19 are formed, a diaphragm 24 including a piezoelectric element 23, a piezoelectric element holding substrate 25 laminated on the diaphragm 24, and a frame member 26 which is a common flow path member laminated on the piezoelectric element holding substrate 25. The nozzle substrate 20 uses a single-crystal silicon wafer as its substrate material, and the flow channel substrate 22, together with the individual liquid chambers 21, forms a supply-side individual flow channel 27 leading to the individual liquid chambers 21 and a recovery-side individual flow channel 28 leading to the individual liquid chambers 21. The piezoelectric element holding substrate 25 uses a single crystal silicon wafer as a substrate material, and forms a supply-side intermediate individual flow path 31 that communicates with the supply-side individual flow path 27 through the opening 29 of the diaphragm 24, and a recovery-side intermediate individual flow path 32 that communicates with the recovery-side individual flow path 28 through the opening 30 of the diaphragm 24.

[0011] The piezoelectric element holding substrate 25 and the frame member 26 form a supply common flow path 33 that communicates with the supply-side intermediate individual flow path 31 and a recovery common flow path 34 that communicates with the recovery-side intermediate individual flow path 32. The supply common flow path 33 communicates with the supply port 36 through the flow path 35 of the manifold 14. The recovery common flow path 34 communicates with the recovery port 38 through the flow path 37 of the manifold 14. The printed circuit board 17 and the piezoelectric element 23 are connected via a flexible wiring member 16, and a driver IC 15 is mounted on the flexible wiring member 16. In, an actuator unit 40 is configured in the members such as the nozzle substrate 20, the flow path member 22, the piezoelectric element 23, and the actuator (not shown) with diagonal lines. In the present embodiment, the plurality of liquid ejection heads 11 are attached to the base member 12 at predetermined intervals. The attachment of the liquid ejection head 11 to the base member 12 is achieved by inserting the liquid ejection head 11 into the opening 39 provided in the base member 12 and joining and fixing the peripheral edge of the nozzle substrate 20 constituting the liquid ejection head 11 to the cover member 13 joined and fixed to the base member 12. Also, a flange portion (not shown) provided outside the frame member 26 of the liquid ejection head 11 is joined and fixed to the base member 12. Note that the fixing structure between the liquid ejection head 11 and the base member 12 is not limited to the above configuration, and any configuration such as adhesion, caulking, screw fixing, etc. may be adopted. In this configuration, the liquid ejection head 11 is reciprocally moved in a direction parallel to the main scanning direction described later by a moving mechanism (not shown). Figure 1 In, the actuator unit 40 is configured in the members such as the nozzle substrate 20, the flow path member 22, the piezoelectric element 23, and the actuator (not shown) with diagonal lines. In, the actuator unit 40 is configured in the members such as the nozzle substrate 20, the flow path member 22, the piezoelectric element 23, and the actuator (not shown) with diagonal lines.

[0012] In the present embodiment, the plurality of liquid ejection heads 11 are attached to the base member 12 at predetermined intervals. The attachment of the liquid ejection head 11 to the base member 12 is achieved by inserting the liquid ejection head 11 into the opening 39 provided in the base member 12 and joining and fixing the peripheral edge of the nozzle substrate 20 constituting the liquid ejection head 11 to the cover member 13 joined and fixed to the base member 12. Also, a flange portion (not shown) provided outside the frame member 26 of the liquid ejection head 11 is joined and fixed to the base member 12. Note that the fixing structure between the liquid ejection head 11 and the base member 12 is not limited to the above configuration, and any configuration such as adhesion, caulking, screw fixing, etc. may be adopted. In this configuration, the liquid ejection head 11 is reciprocally moved in a direction parallel to the main scanning direction described later by a moving mechanism (not shown).

[0013] Figure 2 shows the arrangement of nozzles 19 formed on a conventional nozzle substrate 20. In a conventional nozzle substrate 20, multiple nozzles 19 are arranged in parallel in the sub-scanning direction, which is the transport direction of the recording medium, forming a nozzle row. Multiple rows (four rows, A to D in this example) of this nozzle row are formed in the main scanning direction, which is perpendicular to the sub-scanning direction. Having described the problems with the multi-pass method, the problems with the liquid discharge head 11 equipped with the nozzle substrate 20 shown in Figure 2 will be explained below.

[0014] Figure 4 is a schematic diagram showing the effect of airflow on a liquid ejection head 11 equipped with a nozzle substrate 20. In an ideal state, no airflow is generated in the liquid ejection head 11 due to head movement, and the ink, which is the liquid ejected from each nozzle 19, lands perpendicular to the recording medium. However, in actual devices, as shown in Figure 4, the airflow due to head movement and the ejection airflow due to ink droplets flying in the upstream space interfere with each other, generating airflow vortices, and the ink ejected from each nozzle 19 lands at a position shifted from the ideal position. Here, the airflow due to head movement affects the nozzle row D formed on the nozzle substrate 20 in the forward path, and the same nozzle row A in the return path.

[0015] To address the aforementioned problems, the present invention reduces the nozzle density on the upstream side of the liquid ejection head's movement compared to the downstream side, thereby reducing the ejection airflow on the upstream side. This suppresses interference between the airflow caused by head movement and the ejection airflow on the upstream side, thereby suppressing the occurrence of droplet placement misalignment and forming high-quality images. Furthermore, to similarly suppress airflow interference in both the forward and return paths, the nozzle density of the outer nozzle rows (nozzle rows A and D in Figure 4), located outside the nozzle substrate, is reduced. This configuration suppresses the occurrence of ink droplet placement misalignment on the recording medium in both the forward and return paths without complicating the drive control mechanism of the liquid ejection head, resulting in high-quality images. The following explanation will be based on the drawings.

[0016] Figure 5 shows a nozzle substrate 20A according to a first embodiment of the present invention. The nozzle substrate 20A, which is attached to the liquid discharge head 11, differs from the nozzle substrate 20 shown in Figure 2 in that the position of the nozzle 19 is different. The nozzle substrate 20A has multiple nozzles 19 arranged in parallel in the sub-scanning direction to form nozzle rows, and multiple rows (four rows, A to D in this example) of these nozzle rows are formed in the main scanning direction, which is perpendicular to the sub-scanning direction. Of the nozzle rows A to D, nozzle rows A and D located outside the nozzle substrate 20A in the main scanning direction constitute the outer nozzle row, and nozzle rows B and C located inside the nozzle substrate 20A in the same direction constitute the inner nozzle row.

[0017] In the configuration shown in Figure 5, the density of nozzles 19 in the inner nozzle rows B and C is configured such that the desired image resolution is, for example, 150 dpi. On the other hand, the density of nozzles 19 in the outer nozzle rows A and D is configured such that the resolution is 75 dpi, which is half the density of the inner nozzle rows. This configuration reduces the number of ink ejection nozzles 19, thereby reducing the ejection airflow and suppressing the generation of airflow vortices, resulting in high-quality images. This provides a liquid ejection head that can suppress variations in ink landing position due to airflow influence, regardless of the transport direction of the head.

[0018] Figure 6 shows a nozzle substrate 20B according to a second embodiment of the present invention. The nozzle substrate 20B, which is attached to the liquid discharge head 11, differs from the nozzle substrate 20A shown in Figure 5 in that it has nozzle rows A' and D', which are other outer nozzle rows, outside of the outer nozzle rows A and D. Nozzle row A' has the same nozzle density as nozzle row A, resulting in a resolution of 75 dpi, and each nozzle 19 is positioned in a location corresponding to the position of the nozzle 19 that was removed from nozzle row B in nozzle row A. Nozzle row D' has the same nozzle density as nozzle row D, resulting in a resolution of 75 dpi, and each nozzle 19 is positioned in a location corresponding to the position of the nozzle 19 that was removed from nozzle row C in nozzle row D. This configuration allows for the same effects as in the first embodiment, while also ensuring the overall resolution of the liquid discharge head 11 and enabling the acquisition of even better images.

[0019] Figure 7 shows a nozzle substrate 20C according to a third embodiment of the present invention. The nozzle substrate 20C, which is attached to the liquid discharge head 11, differs from the nozzle substrate 20B shown in Figure 6 in that each corner of the rectangular nozzle substrate 20C is chamfered 20Ca (C chamfer). With this configuration, the reciprocating liquid discharge head 11 has a shape closer to a streamlined shape with respect to the direction of movement compared to the first and second embodiments, which reduces the airflow caused by the head movement, suppresses the generation of airflow vortices and allows for the acquisition of images with good image quality. The chamfer 20Ca may also be an R chamfer, and an R chamfer can reduce air resistance more effectively than a C chamfer, and further suppress the generation of airflow.

[0020] Figure 8 shows a nozzle substrate 20D according to a fourth embodiment of the present invention. The nozzle substrate 20D, which is attached to the liquid discharge head 11, differs from the nozzle substrate 20C shown in Figure 7 in that it has additional outer nozzle rows A' and D' outside of the other outer nozzle rows A' and D'. Furthermore, the nozzle substrate 20D differs from the nozzle substrate 20C in that the density of nozzles 19 in nozzle rows A, A', A”, D, D', D”, is 1 / 3 of the density of nozzles 19 in nozzle rows B, C, and that each corner of the rectangular nozzle substrate 20D is chamfered 20Da (C chamfer).

[0021] The nozzle density in nozzle row A is set to a density that results in a resolution of 50 dpi, which is 1 / 3 of the density in nozzle row B, and is arranged in such a way that two of the three nozzles 19 that are arranged in series in nozzle row B are removed. Nozzle row A' is set to a density that results in a resolution of 50 dpi, which is the same as nozzle row A, and each nozzle 19 is positioned in nozzle row A corresponding to the position of the upstream nozzle 19 of the two nozzles 19 that were removed from nozzle row B. Nozzle row A'' is set to a density that results in a resolution of 50 dpi, which is the same as nozzle row A, and each nozzle 19 is positioned in nozzle row A corresponding to the position of the downstream nozzle 19 of the two nozzles 19 that were removed from nozzle row B.

[0022] The nozzle density in nozzle row D is one-third of the density in nozzle row C, resulting in a resolution of 50 dpi. Nozzle row D' is configured such that two of the three nozzles 19 that were in series in nozzle row C are removed. Nozzle row D' has the same nozzle density as nozzle row D, resulting in a resolution of 50 dpi, and each nozzle 19 is positioned in nozzle row D corresponding to the position of the downstream nozzle 19 of the two nozzles 19 removed from nozzle row C. Nozzle row D'' has the same nozzle density as nozzle row D, resulting in a resolution of 50 dpi, and each nozzle 19 is positioned in nozzle row D corresponding to the position of the upstream nozzle 19 of the two nozzles 19 removed from nozzle row C.

[0023] In the fourth embodiment, since the density of nozzles 19 in nozzle row A, which is the outer nozzle row, is 1 / 3 of the density of nozzles 19 in nozzle row B, which is the inner nozzle row, the other outer nozzle rows A' and A'' are provided in two rows outside of outer nozzle row A. The same applies to nozzle rows D' and D''. Each corner of the rectangular nozzle substrate 20D is chamfered 20Da (C chamfer). The chamfer width of chamfer 20Da is larger than that of chamfer 20Ca shown in the third embodiment, and in this example, it is formed to be 1.5 times the chamfer width of chamfer 20Ca. Note that chamfer 20Da may also be R chamfer.

[0024] With this configuration, the size of the chamfer 20Da increases in proportion to the number of other outer nozzle rows provided. As a result, the reciprocating liquid discharge head 11 becomes more streamlined in the direction of movement compared to the third embodiment, further reducing the airflow caused by head movement, suppressing the generation of airflow vortices, and enabling the acquisition of images with even better image quality.

[0025] Figure 9 shows a nozzle substrate 20E according to a fifth embodiment of the present invention. The nozzle substrate 20E, which is attached to the liquid discharge head 11, differs from the nozzle substrate 20A shown in Figure 5 in that the spacing L1 between the outer nozzle rows A and D and the inner nozzle rows B and C is narrower than the spacing W1 between each nozzle 19 in nozzle rows B and C. Spacing W1 is the same as the spacing between each nozzle 19 that constitutes the density of nozzles 19 that make up a resolution of 150 dpi, and the spacing L2 between nozzle rows B and C is the same as spacing W1.

[0026] This configuration allows for a lower density of outer nozzles compared to inner nozzle rows, thereby suppressing the generation of airflow vortices even when the spacing L1 is smaller than the spacing W1, resulting in high-quality images. Furthermore, the length L of the nozzle substrate 20E can be made smaller than that of the nozzle substrate 20A, enabling miniaturization of the liquid discharge head 11.

[0027] Next, a liquid dispensing device equipped with the liquid dispensing head 11 described above will be explained. As shown in Figures 10 and 11, the printing apparatus 500, which is both a liquid ejection device and an image forming apparatus, includes an incoming means 501 for loading the continuous body 510, which is the recording medium, and a guiding and transporting means 503 for guiding and transporting the continuous body 510 loaded by the incoming means 501 toward the printing means 505. The printing apparatus 500 also includes a printing means 505 that performs a printing operation to form an image by ejecting liquid onto the continuous body 510, a drying means 507 for drying the continuous body 510 to which the liquid has adhered, and an outgoing means 509 for unloading the continuous body 510.

[0028] The continuous material 510 is fed out from the main winding roller 511 of the loading means 501, guided and transported by rollers of the loading means 501, the guiding and transporting means 503, the drying means 507, and the unloading means 509, and then wound onto the winding roller 591 of the unloading means 509. In the printing means 505, the continuous material 510 is transported on the transport guide member 559 facing the head unit 550, which is a liquid discharge unit, and an image is printed by the liquid discharged from the head unit 550.

[0029] The printing apparatus 500 is equipped with liquid ejection units 10A and 10B similar to the liquid ejection unit 10 described above on the head unit 550, and each liquid ejection unit 10A and 10B is mounted on a common base member 552. Each liquid dispensing unit 10A, 10B, when the direction in which the liquid dispensing heads 11 are arranged in a direction perpendicular to the continuum transport direction is defined as the head arrangement direction, will dispense liquid of the same color from the head row 11A1, 11A2 set of liquid dispensing unit 10A. Similarly, the head row 11B1, 11B2 set of liquid dispensing unit 10A, the head row 11C1, 11C2 set of liquid dispensing unit 10B, and the head row 11D1, 11D2 set of liquid dispensing unit 10B will dispense liquid of the desired color, respectively.

[0030] Next, another example of a printing apparatus that is a liquid ejection device according to the present invention will be described with reference to Figures 12 and 13. The printing apparatus 400, which is both a liquid ejection device and an image forming apparatus, is a serial type printing apparatus, and the carriage 403 reciprocates in the main scanning direction by the main scanning movement mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, etc. The guide member 401 is stretched across the left and right side plates 491A and 491B and holds the carriage 403 in a movable position. The carriage 403 reciprocates in the main scanning direction by receiving the driving force of the main scanning motor 405 via the timing belt 408 stretched between the drive pulley 406 and the driven pulley 407.

[0031] The carriage 403 is equipped with a liquid dispensing unit 440 which integrally includes a liquid dispensing head 11 and a head tank 441. Here, the liquid dispensing head 11 dispenses liquids of various colors, such as yellow (Y), cyan (C), magenta (M), and black (K). The liquid dispensing head 11 is mounted with a nozzle row consisting of multiple nozzles arranged in a sub-scanning direction perpendicular to the main scanning direction, and with the liquid dispensing direction facing downwards. The liquid dispensing head 11 is connected to a liquid circulation device (not shown), and the liquid of the desired color is circulated and supplied to the liquid dispensing head 11.

[0032] The printing apparatus 400 is equipped with a transport mechanism 495 for transporting the paper 410, which is the recording medium. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 that drives the transport belt 412. The transport belt 412, which is an endless belt, is stretched between a transport roller 413 and a tension roller 414, and is used to pick up the paper 410 and transport it to a position facing the liquid discharge head 11. Pickup is performed by electrostatic attraction or air suction, etc. The transport belt 412 is moved circumferentially in the sub-scanning direction by the driving force of the sub-scanning motor 416 being transmitted via a timing belt 417 and a timing pulley 418.

[0033] A maintenance and recovery mechanism 420 for maintaining and restoring the liquid discharge head 11 is positioned on one side of the carriage 403 in the main scanning direction and to the side of the conveyor belt 412. The maintenance and recovery mechanism 420 consists of, for example, a cap member 421 that caps the nozzle surface of the liquid discharge head 11, and a wiper member 422 that wipes the nozzle surface. The main scanning movement mechanism 493, the maintenance and recovery mechanism 420, and the conveyor mechanism 495 are mounted on a housing that includes side plates 491A, 491B, and a back plate 491C. In the printing apparatus 400 with the above configuration, the paper 410 is held in place by the transport belt 412, and the paper 410 is transported in the sub-scanning direction by the circular movement of the transport belt 412. At this time, the carriage 403 is moved in the main scanning direction, and the liquid ejection head 11 is driven according to the image signal, thereby ejecting liquid onto the stationary paper 410 to form an image.

[0034] Next, the liquid dispensing unit 440 described above will be explained based on Figure 14. The liquid ejection unit 440 is composed of a housing portion consisting of side plates 491A, 491B and a back plate 491C, as well as a main scanning movement mechanism 493, a carriage 403, a liquid ejection head 11, and other components that make up the printing apparatus 400, which is a liquid ejection device and an image forming apparatus. Furthermore, it is also possible to configure a liquid dispensing unit in which the maintenance and recovery mechanism 420 described above is further attached to, for example, the side plate 491B of the liquid dispensing unit 440.

[0035] Next, another example of a liquid dispensing unit according to one embodiment of the present invention will be described with reference to Figure 15. The liquid discharge unit 450 shown in Figure 15 has a liquid discharge head 11 to which a flow path component 444 is attached, and a tube 456 connected to the flow path component 444. The flow path component 444 is located inside a cover 442, and a connector 443 for electrical connection to the liquid discharge head 11 is provided on the upper part of the flow path component 444. A configuration including a head tank 441 instead of the flow path component 444 is also possible. In the liquid ejection units 10, 10A, 10B, 440, 450, 550, and the printing devices 400, 500, which are liquid ejection devices, the same effects and benefits as those of the liquid ejection head 11 described above can be obtained.

[0036] In the present invention, the liquid used is not particularly limited as long as it has a viscosity and surface tension that can be dispensed from the head, but it is preferable that its viscosity becomes 30 mPa·s or less at room temperature and atmospheric pressure, or upon heating and cooling. More specifically, this includes solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functional materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium, edible materials such as natural pigments, and solutions, suspensions, and emulsions containing these. These can be used, for example, in inkjet inks, surface treatment liquids, and three-dimensional molding material liquids. The energy source for discharging liquid includes piezoelectric actuators (multilayer piezoelectric elements and thin-film piezoelectric elements), thermal actuators using electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a diaphragm and a counter electrode.

[0037] The "liquid discharge head" is not limited to any particular pressure generating means. For example, in addition to the piezoelectric actuator described above (which may use a multilayer piezoelectric element), it may also use a thermal actuator that uses an electrothermal conversion element such as a heating resistor, or an electrostatic actuator consisting of a diaphragm and a counter electrode. A "liquid discharge unit" is a liquid discharge head with integrated functional components and mechanisms, and includes an assembly of parts related to liquid discharge. For example, a "liquid discharge unit" may include a combination of a liquid discharge head with at least one of the following components: a head tank, carriage, supply mechanism, maintenance and recovery mechanism, main scanning movement mechanism, and liquid circulation device. Here, integration includes, for example, cases where a liquid dispensing head and functional components or mechanisms are fixed to each other by fastening, bonding, engaging, etc., or where one is held movably relative to the other. Furthermore, the liquid dispensing head and functional components or mechanisms may be detachable from each other.

[0038] Liquid dispensing units can be configured with an integrated liquid dispensing head and head tank, or with the two integrated by being connected to each other via tubing or similar means. It is also possible to add a unit containing a filter between the liquid dispensing head and head tank of these liquid dispensing units. Furthermore, liquid dispensing units include those in which the liquid dispensing head and carriage are integrated, and those in which the liquid dispensing head, carriage, and main scanning movement mechanism are integrated. Additionally, some liquid dispensing units have the liquid dispensing head movably held by a guide member that constitutes part of the scanning movement mechanism, and the liquid dispensing head and scanning movement mechanism are integrated.

[0039] Some liquid discharge units integrate the liquid discharge head, carriage, and maintenance / recovery mechanism by fixing a cap component, which is part of the maintenance / recovery mechanism, to a carriage to which the liquid discharge head is attached. Other liquid discharge units integrate the liquid discharge head and supply mechanism by connecting a tube to a liquid discharge head to which a head tank or flow path component is attached. Liquid from a liquid storage source is supplied to the liquid discharge head via this tube. The main scanning movement mechanism shall include the guide member alone. The supply mechanism shall include the tube alone and the loading section alone.

[0040] In this invention, the liquid discharge unit is described in combination with a liquid discharge head, but the liquid discharge unit also includes a head module that includes the liquid discharge head described above, and a head unit in which the functional components and mechanisms described above are integrated. Liquid dispensing devices include those equipped with a liquid dispensing head, liquid dispensing unit, head module, head unit, etc., which drive the liquid dispensing head to dispense liquid. Liquid dispensing devices include not only those capable of dispensing liquid onto surfaces to which liquid can adhere, but also those capable of dispensing liquid into gases or liquids.

[0041] The liquid dispensing device may also include means for feeding, conveying, and dispensing paper onto materials to which liquid can adhere, as well as other pre-treatment and post-treatment devices. Examples of liquid ejection devices include image forming devices that eject ink to form an image on a recording medium, and three-dimensional molding devices that eject molding liquid onto a powder layer formed in layers to create three-dimensional objects. Furthermore, liquid dispensing devices are not limited to those that visualize meaningful images such as letters or figures through the dispensed liquid. For example, they also include devices that form patterns that do not have meaning in themselves, or devices that create three-dimensional images.

[0042] The above-mentioned objects to which liquids can adhere refer to objects to which liquids can adhere, at least temporarily, including those that adhere and solidify or adhere and penetrate. Specific examples include recording media such as paper, film, and cloth; electronic components such as electronic circuit boards and piezoelectric elements; powder layers; organ models; and inspection cells. Unless otherwise specified, it includes all objects to which liquids can adhere. The material to which the liquid can adhere may be any material, such as paper, thread, fibers, fabric, leather, metal, plastic, glass, wood, or ceramics, as long as the liquid can adhere to it, even temporarily.

[0043] Other examples of liquid dispensing devices include processing liquid coating devices that dispense processing liquid onto the surface of paper for purposes such as modifying the surface of the paper, and injection granulation devices that granulate fine particles of raw materials by spraying a composition liquid, in which raw materials are dispersed in a solution, through a nozzle.

[0044] The liquid dispensing apparatus of the present invention also includes apparatus for manufacturing electrodes and electrochemical elements. The electrode manufacturing apparatus will be described below. Figure 16 is a schematic diagram showing an example of an electrode manufacturing apparatus according to one embodiment of the present invention. The electrode manufacturing apparatus 700 is an apparatus for manufacturing an electrode including a layer having electrode material by discharging a liquid composition using a liquid discharging unit including a liquid discharging head. First, the means and process for forming the layer containing the electrode material will be described.

[0045] The liquid discharge means provided in the electrode manufacturing apparatus 700 shown in Figure 16 is the liquid discharge unit of the present invention described above. A liquid composition is discharged from the liquid discharge head of the liquid discharge unit, thereby applying the liquid composition to the target object and forming a liquid composition layer. The target object (hereinafter sometimes referred to as the "discharge target object") is not particularly limited as long as it is an object on which a layer containing electrode material is formed, and can be appropriately selected according to the purpose. For example, the target object may be an electrode substrate (current collector), an active material layer, a layer containing solid electrode material, etc. The target object may also be an electrode composite layer containing active material on an electrode substrate. Furthermore, the discharge means and discharge process may be means and processes for forming a layer containing electrode material by directly discharging the liquid composition, as long as it is possible to form a layer containing electrode material on the discharge target object. Moreover, the discharge means and discharge process may be means and processes for forming a layer containing electrode material by indirectly discharging the liquid composition.

[0046] Next, we will describe the other components and processes. Other components included in the electrode composite layer manufacturing apparatus are not particularly limited as long as they do not impair the effects of the present invention and can be appropriately selected according to the purpose. Similarly, other steps included in the electrode composite layer manufacturing method are not particularly limited as long as they do not impair the effects of the present invention and can be appropriately selected according to the purpose. For example, components and steps included in the electrode composite layer manufacturing apparatus and manufacturing method include heating means and heating steps.

[0047] Next, the heating means and heating process will be described. The heating means included in the electrode composite layer manufacturing apparatus is a means for heating the liquid composition discharged by the discharge means. Furthermore, the heating step included in the electrode composite layer manufacturing method is a step for heating the liquid composition discharged in the discharge step. By heating the liquid composition, it can be dried.

[0048] Next, we will describe a configuration in which a layer containing electrode material is formed by the direct discharge of a liquid composition. Here, as an example of an electrode manufacturing apparatus that forms a layer containing electrode material, we will describe an electrode manufacturing apparatus that forms an electrode composite layer containing active material on an electrode substrate (current collector). As shown in Figure 16, the electrode manufacturing apparatus 700 includes an ejection process section 110 which includes a step of applying a liquid composition onto a printing substrate 704 having an object to be ejected to form a liquid composition layer, and a heating process section 130 which includes a heating step of heating the liquid composition to obtain an electrode composite layer.

[0049] The electrode manufacturing apparatus 700 is equipped with a transport means 705 for transporting the printing substrate 704, and the transport means 705 transports the printing substrate 704 at a preset speed in the order of the discharge process section 110 and the heating process section 130. There are no particular restrictions on the method for manufacturing the printing substrate 704 having an object to be discharged, such as an active material layer, and well-known methods can be appropriately selected. The discharge process section 110 is equipped with a liquid discharge head 281a for realizing a liquid composition application process for applying a liquid composition onto the printing substrate 704, a storage container 281b for containing the liquid composition 707, a supply tube 281c for supplying the liquid composition 707 in the storage container 281b to the liquid discharge head 281a, and the like.

[0050] In the discharge process section 110, the liquid composition 707 is discharged from the liquid discharge head 281a, and the liquid composition 707 is applied to the printing substrate 704 to form a thin film layer of the liquid composition. The containment container 281b may be integrated with the electrode composite layer manufacturing apparatus, or it may be detachable from the electrode composite layer manufacturing apparatus. Alternatively, the containment container 281b may be a container used for adding to a containment container integrated with the electrode composite layer manufacturing apparatus, or a containment container detachable from the electrode composite layer manufacturing apparatus. The containment container 281b and the supply tube 281c can be arbitrarily selected as long as they are capable of stably containing and supplying the liquid composition 707.

[0051] In the heating section 130, a solvent removal step is performed to remove any solvent remaining in the liquid composition layer by heating. Specifically, the solvent remaining in the liquid composition layer is removed from the liquid composition layer by drying it with heating by the heating device 703 provided in the heating section 130, thereby forming the electrode composite layer. Furthermore, the solvent removal step in the heating section 130 may be performed under reduced pressure.

[0052] There are no particular restrictions on the heating device 703, and it can be appropriately selected according to the purpose. For example, the heating device 703 can be a substrate heater, an IR heater, a hot air heater, etc. The heating device 703 may also be a combination of at least two of the substrate heater, IR heater, and hot air heater. The heating temperature and heating time can be appropriately selected according to the boiling point of the solvent contained in the liquid composition 707 or the film thickness to be formed.

[0053] In the electrode manufacturing apparatus 700, the same type of liquid discharge head 281a as the liquid discharge head 11 described above is used. By using the electrode manufacturing apparatus 700 according to an embodiment of the present invention, a liquid composition can be discharged to a target position on the object to be discharged. The electrode mixture layer can be suitably used, for example, as part of the configuration of an electrochemical element. There are no particular restrictions on the components of the electrochemical element other than the electrode mixture layer, and well-known components can be appropriately selected. Examples of components other than the electrode mixture layer include a positive electrode, a negative electrode, a separator, etc.

[0054] Examples of the present invention are as follows: [1] A liquid discharge head comprising a nozzle substrate on which a plurality of nozzles are formed, which discharges droplets onto a recording medium to be transported in the sub-scanning direction from the nozzles, which is movable in the main scanning direction perpendicular to the sub-scanning direction, wherein the nozzle substrate has a plurality of nozzle rows formed in the main scanning direction, each consisting of a plurality of nozzles arranged in parallel in the sub-scanning direction, and the density of the nozzles forming the outer nozzle row, which is the nozzle row located outside the nozzle substrate in the main scanning direction, is lower than the density of the nozzles forming the inner nozzle row, which is the nozzle row located inside the nozzle substrate in the main scanning direction. [2] The liquid discharge head according to [1], wherein the outer nozzle row has another outer nozzle row outside the outer nozzle row, the nozzles are formed at the same density as the outer nozzle row and the positions of the nozzles in the main scanning direction are different from those of the outer nozzle row, and the outer nozzle row and the other outer nozzle row constitute the desired image resolution. [3] The liquid discharge head according to [2] is characterized in that the nozzle substrate has a rectangular shape with chamfered edges on all corners. [4] The liquid discharge head according to [3], characterized in that when the resolution based on the density of the nozzles forming the outer nozzle row and the other outer nozzle row is 1 / n (n>2) of the resolution of the desired image, the other outer nozzle row is provided with n-1 rows, and the size of the chamfer increases in proportion to n. [5] A liquid discharge head according to any one of [1] to [4], characterized in that the distance between the outer nozzle row and the inner nozzle row is narrower than the distance between each nozzle in the inner nozzle row. A liquid dispensing unit characterized by having a liquid dispensing head as described in any one of [6][1] to [5]. A liquid dispensing device characterized by having a liquid dispensing head described in any one of [7][1] to [5]. A liquid dispensing device characterized by having the liquid dispensing unit described in [8][6].

[0055] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the spirit of the invention as described in the claims, unless otherwise specifically limited in the above description. The effects described in the embodiments of the present invention are merely illustrative of the most preferred effects that may arise from the present invention, and the effects of the present invention are not limited to those described in the embodiments. [Explanation of Symbols]

[0056] 10, 10A, 10B, 440, 450 Liquid Dispensing Unit 11,281a ​​Liquid dispensing head 19 nozzles 20A, 20B, 20C, 20D, 20E Nozzle substrate 20Ca, 20Da chamfering 400,500 Liquid ejection device (printing device) 700 Liquid discharge equipment (electrode manufacturing equipment) [Prior art documents] [Patent Documents]

[0057] [Patent Document 1] Patent No. 5936501

Claims

1. A nozzle substrate is provided, which has multiple nozzles formed on it. A droplet is ejected from the nozzle onto the recording medium being transported in the sub-scanning direction. It is movable in the main scanning direction which is perpendicular to the sub-scanning direction, The nozzle substrate has a nozzle row consisting of a plurality of nozzles arranged in parallel in the sub-scanning direction. Multiple columns are formed in the main scanning direction, The outer nozzle row, which is arranged outside the nozzle substrate in the main scanning direction, The density of the nozzles forming the slide row is such that in the main scanning direction the nozzle substrate is located on the inside of the nozzle substrate. The density of the nozzles forming the inner nozzle row, which is the arranged nozzle row, is lower than the density of the nozzles. Outside the outer nozzle row, the nozzles are formed at the same density as the outer nozzle row. The position of the nozzle in the aforementioned sub-scanning direction is different from that of the other outer nozzle row. The outer nozzle row and the other outer nozzle row constitute the desired image resolution. A liquid dispensing head.

2. In the liquid dispensing head according to claim 1, The aforementioned nozzle substrate is characterized by having a rectangular shape with chamfered edges on all corners, and is suitable for liquids. Dispensing head.

3. In the liquid dispensing head according to claim 2, Solution based on the density of the nozzles forming the outer nozzle row and the other outer nozzle row. When the image intensity is 1 / n (n > 2) of the desired image resolution, the other outer nozzle row The liquid is characterized by having n-1 rows, and the size of the chamfer increasing in proportion to n. Body discharge head.

4. In the liquid dispensing head according to claim 3, The distance between the outer nozzle row and the inner nozzle row is such that the inner nozzle row is formed by A liquid dispensing head characterized by having a spacing narrower than the spacing between multiple adjacent nozzles.

5. A liquid characterized by comprising a liquid dispensing head according to any one of claims 1 to 4. Discharge unit.

6. A liquid characterized by comprising a liquid dispensing head according to any one of claims 1 to 4. Discharge device.

7. A liquid dispensing device characterized by having the liquid dispensing unit described in claim 5.

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