Manufacturing method of liquid ejection head and manufacturing method of liquid ejection device

Abstract

To suppress variation in discharge properties in a liquid discharge head for discharging liquid by vibrating a nozzle plate.SOLUTION: A method for manufacturing a liquid discharge head for discharging liquid by vibrating a nozzle plate 1 including a substrate 81 and a piezoelectric body 82 includes: a piezoelectric body formation step of forming the piezoelectric body 82 on the substrate 81 at 450°C to 600°C; and a nozzle hole formation step of forming a nozzle hole 4 penetrating the substrate 81 and the piezoelectric body 82.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Among liquid ejection heads using piezoelectric bodies, there are known liquid ejection heads that eject ink by vibrating the nozzle surface, and it is known that such liquid ejection heads require large vibrations in order to eject ink.

[0003] Patent Document 1 discloses a head structure provided with nozzle holes penetrating a nozzle substrate plate and a piezoelectric thin film, which is said to enable ink droplet ejection energy to be increased and stable ink ejection to be performed.

[0004] Also, Patent Document 2 discloses that the nozzle part of the vibration substrate is vibrated to generate a standing wave near the surface of the liquid ink held in the nozzle toward the center of the nozzle, and droplets are ejected from the ink surface at the center of the nozzle. This is said to be highly energy efficient and capable of ejecting small droplets. Also, Patent Document 1 discloses an embodiment in which two substrates are bonded together to form a nozzle penetrating both substrates, and the substrates around the nozzle are vibrated to eject droplets.

[0005] However, conventional technology has not yet been able to ensure sufficient vibration. In order to ensure sufficient vibration, it is conceivable to attempt to increase the piezoelectric constant of the piezoelectric body by, for example, depositing the piezoelectric body at a high temperature, thereby obtaining a large displacement. Summary of the Invention [Problem to be solved by the invention]

[0006] However, when the conventional manufacturing method for thin film piezoelectric materials is applied to a liquid ejection head that ejects ink by vibrating the nozzle surface, the substrate warps due to excessive temperature, etc. If nozzle holes are formed on a substrate in a warped state, there is a problem that the nozzle shape within the substrate varies, resulting in variations in the ejection characteristics.

[0007] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to suppress variations in ejection characteristics in a liquid ejection head that ejects liquid by vibrating a nozzle plate. [Means for solving the problem]

[0008] In order to solve the above problems, the manufacturing method of the liquid ejection head of the present invention is a manufacturing method of a liquid ejection head in which a nozzle plate having a substrate and a piezoelectric body vibrates to eject liquid, and includes a piezoelectric body forming step of forming a film of the piezoelectric body on the substrate at 450°C to 600°C, and a nozzle hole forming step of forming a nozzle hole penetrating the substrate and the piezoelectric body. The piezoelectric body forming step forms the piezoelectric body by a sputtering method or a CVD (Chemical Vapor Deposition) method. It is characterized by: Effect of the Invention

[0009] According to the present invention, in a liquid ejection head that ejects liquid by vibrating a nozzle plate, it is possible to suppress variations in ejection characteristics. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view of an example of a liquid ejection head according to the present invention. [Diagram 2] 1 is a schematic cross-sectional view of a main portion of an example of a liquid ejection head according to the present invention. [Diagram 3] 1 is a schematic exploded perspective view of a main portion of an example of a liquid ejection head according to the present invention. [Figure 4] 1 is an exploded perspective schematic view of an example of a liquid ejection head according to the present invention. [Diagram 5] FIG. 4 is a schematic cross-sectional view of a liquid ejection head according to a comparative example. [Figure 6] FIG. 4 is a schematic cross-sectional view of a main part of a liquid ejection head according to a comparative example. [Figure 7] FIG. 2 is a schematic cross-sectional view of an example of a liquid ejection head. [Figure 8] FIG. 11 is a schematic cross-sectional view of another example of a liquid ejection head. [Figure 9] FIG. 11 is a schematic cross-sectional view of another example of a liquid ejection head. [Figure 10] FIG. 11 is a schematic perspective view of another example of a liquid ejection head. [Figure 11] FIG. 1 is a schematic diagram of an example of a liquid ejection device. [Figure 12] FIG. 2 is a schematic diagram of an example of a head unit. [Figure 13] FIG. 1 is a block diagram illustrating an example of a liquid circulation device. [Figure 14] FIG. 11 is a schematic diagram of another example of the liquid ejection device. [Figure 15] FIG. 11 is a schematic diagram of another example of the liquid ejection device. [Figure 16] FIG. 2 is a schematic diagram of an example of a liquid ejection unit. [Figure 17] FIG. 11 is a schematic diagram of another example of the liquid ejection unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a method for manufacturing a liquid ejection head and a method for manufacturing a liquid ejection device according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiments, and may be modified within the scope of what a person skilled in the art can imagine, such as other embodiments, additions, modifications, deletions, etc., and any aspect is within the scope of the present invention as long as it provides the functions and effects of the present invention.

[0012] The manufacturing method for a liquid ejection head of the present embodiment is a manufacturing method for a liquid ejection head in which a nozzle plate having a substrate and a piezoelectric body vibrates to eject liquid, and is characterized by including a piezoelectric body forming process in which the piezoelectric body is formed on the substrate at 450°C to 600°C, and a nozzle hole forming process in which a nozzle hole penetrating the substrate and the piezoelectric body is formed.

[0013] Fig. 1 is a schematic cross-sectional view for explaining one example of a liquid ejection head obtained by this embodiment. Fig. 1 shows a nozzle plate 1, a nozzle hole 4, a substrate 81, a piezoelectric body 82, a common liquid chamber plate 83, a common liquid chamber 84, a partition wall 85, a ceiling plate 86, and a supply path 87. Note that the figure shows only the essential parts in order to explain the liquid ejection head of this embodiment, and other members may be provided as necessary.

[0014] Liquid (e.g., ink) is supplied to a common liquid chamber 84 provided in a common liquid chamber plate 83 (common liquid chamber substrate) through a supply path 87 provided in a ceiling plate 86. The ceiling plate 86 may be made of, for example, a metal member, and the common liquid chamber plate 83 may be made of, for example, Si.

[0015] The nozzle plate 1 has a substrate 81 and a piezoelectric body 82 provided on the side of the discharge target. When the nozzle plate 1 vibrates, liquid in a common liquid chamber 84 is discharged from the nozzle holes 4. The number, arrangement, and shape of the nozzle holes 4 can be changed as appropriate, but the nozzle holes 4 are formed to penetrate the substrate 81 and the piezoelectric body 82.

[0016] The nozzle plate 1 may be provided with electrodes in order to eject liquid by vibration of the nozzle plate 1. Known materials can be used for the electrodes.

[0017] Next, a method for manufacturing the liquid ejection head of this embodiment will be described. 2 is a diagram for explaining the process of forming the nozzle plate 1, and is a schematic cross-sectional view of the nozzle plate 1. In FIG. 2, a piezoelectric body forming process and a nozzle hole forming process are performed.

[0018] 2A shows a substrate 81. The substrate 81 can be changed as appropriate, but for example, a Si substrate can be used. When the substrate 81 is a Si substrate, SiO 2 Alternatively, an oxide film such as the above may be formed. The thickness of the substrate 81 is preferably, for example, 200 μm to 900 μm.

[0019] 2(B) is a diagram for explaining the piezoelectric body forming step, in which a piezoelectric body 82 is formed on a substrate 81. The piezoelectric body 82 is preferably made of PZT (lead zirconate titanate). The thickness of the piezoelectric body 82 is preferably 1 μm to 6 μm, for example.

[0020] In the piezoelectric body formation process, the temperature at which the piezoelectric body is formed (film formation temperature ) The deposition temperature is 450°C to 600°C. By keeping the temperature within this range, it is possible to prevent the substrate 81 from warping when forming the piezoelectric body. If the deposition temperature is higher than 600°C, the temperature becomes too high and the substrate 81 warps, causing problems such as variations in the shape of the nozzle holes formed in a later process within the liquid ejection head. If the deposition temperature is lower than 450°C, the piezoelectric body is not sufficiently formed, and sufficient ejection characteristics cannot be obtained.

[0021] The film formation temperature is preferably 450° C. to 550° C. In this case, it is possible to further suppress warping of the substrate 81. This makes it possible to further suppress variations in the ejection characteristics within the liquid ejection head.

[0022] The piezoelectric body 82 can be formed by, for example, a sputtering method, a CVD (Chemical Vapor Deposition) method, a sol-gel method, etc. In the sol-gel method, a precursor solution of the piezoelectric body is applied onto the substrate 81, and then the substrate and the precursor solution of the piezoelectric body are heated at the above-mentioned film formation temperature.

[0023] 2(C) is a diagram for explaining the nozzle hole forming step, in which a nozzle hole 4 is formed penetrating a substrate 81 and a piezoelectric body 82. The method for forming the nozzle hole 4 can be appropriately changed, but for example, dry etching can be used.

[0024] According to the manufacturing method of the liquid ejection head of this embodiment, it is possible to prevent the substrate from warping when forming the piezoelectric body. This makes it possible to suppress the nozzle shape from varying within the liquid ejection head. For example, it is possible to prevent the nozzle holes near the center of the nozzle plate 1 from having different shapes from the nozzle holes on the end sides. In addition, it is possible to prevent the nozzle holes on one end side of the nozzle plate 1 from having different shapes from the nozzle holes on the other end sides.

[0025] This makes it possible to suppress variations in the ejection characteristics of the liquid ejected from each nozzle, such as the droplet volume, droplet speed (droplet velocity), and landing position accuracy, within the liquid ejection head, which further improves the image quality.

[0026] FIG. 3 shows a schematic cross-sectional view of the nozzle plate 1 in this embodiment. FIG. 3(A) is a schematic diagram showing a state in which nozzle holes 4 are formed in a nozzle plate 1. As shown in FIG. Since it is possible to prevent the substrate 81 from warping, it is possible to align the heights of the left and right nozzle holes 4. For example, as shown in the figure, it is possible to align the heights of the nozzle surfaces 1b and 1c near the nozzle holes 4. This also makes it possible to align the shapes of the nozzle holes in the liquid ejection head.

[0027] 3(B) is a diagram showing a schematic example of a case where liquid 88 flows through the nozzle hole 4 and a case where liquid 88 accumulates in the nozzle hole 4. Since the nozzle surfaces 1b and 1c are aligned in the vicinity of the nozzle hole 4, the shape of the meniscus can be made the same on both sides of the central axis of the nozzle hole 4. Furthermore, the shapes of the meniscus can be made uniform between nozzle holes in the liquid ejection head.

[0028] 3(C) is a diagram showing a schematic example of a case where liquid 88 is ejected from the nozzle hole 4, and the arrow shows a schematic direction in which the liquid 88 is ejected. The liquid 88 can be ejected straight from the nozzle hole 4. Also, it is possible to suppress variation in the ejection direction between the nozzle holes 4 in the liquid ejection head.

[0029] Here, a liquid ejection head in a comparative example will be described below. Fig. 5 is a schematic cross-sectional view of the liquid ejection head in the comparative example. In the comparative example, the piezoelectric body 82a is formed at a temperature higher than the film formation temperature in this embodiment, for example, at a temperature exceeding 600°C, which is lower than 800°C, so that the substrate 81a becomes warped, and the nozzle plate 1a also becomes warped.

[0030] If the nozzle holes 4a are formed in this state, the left and right sides of the nozzle holes will have different heights. In addition, the nozzle shape and the internal volume of the nozzles will differ from one another. This causes the ejection characteristics to vary within the liquid ejection head.

[0031] In order to explain the above in detail, an enlarged schematic cross-sectional view of the dashed line portion in FIG. 5 is shown in FIG. As shown in Fig. 6(A), because the nozzle hole 4a is formed in the warped nozzle plate 1a, the left and right sides of the nozzle hole will have different heights. For example, the figure shows that the nozzle surface 1b and the nozzle surface 1c are at different heights.

[0032] When liquid is supplied to the nozzle holes 4a in this state, the height of the meniscus will differ between the left and right sides as shown in Fig. 6(B) and the nozzle shape, internal volume, etc. will differ from nozzle to nozzle.

[0033] In this case, as shown in Fig. 6C, not only does the ejection bend occur, but the amount of the ejection bend varies from nozzle to nozzle. In addition, the amount of liquid droplets ejected from each nozzle, the droplet speed (velocity of the droplets), and the landing position accuracy vary from nozzle to nozzle, and the ejection characteristics vary within the liquid ejection head. This causes problems such as failure to obtain good quality images.

[0034] Next, a description will be given of the bonding process and the like in the manufacturing method for the liquid ejection head of this embodiment. Fig. 4 is an exploded perspective view for explaining this embodiment.

[0035] Fig. 4(A) is a schematic perspective view of a ceiling plate 86. A supply path 87 is formed in the ceiling plate 86. Fig. 4(B) is a schematic perspective view of a common liquid chamber plate 83 (common liquid chamber substrate). A common liquid chamber 84 is formed in the common liquid chamber plate 83. Fig. 4(C) is a schematic perspective view of a nozzle plate 1, which is the nozzle plate 1 obtained in Fig. 3.

[0036] By bonding the respective members shown in Fig. 4, it is possible to obtain the liquid ejection head of this embodiment shown in Fig. 1. In the bonding process in this embodiment, after the nozzle hole forming process, a ceiling plate 86 is bonded to the substrate 81 side of the nozzle plate 1.

[0037] According to the present embodiment, there is also provided a method for manufacturing a liquid ejection head, which is a method for manufacturing a liquid ejection device using the method for manufacturing a liquid ejection head of the present embodiment.

[0038] (Example 1 and Comparative Example 1) In Example 1, as shown in Fig. 2 to Fig. 4, the liquid ejection head shown in Fig. 1 is manufactured. First, a SiO 2 This was used as a substrate 81. Next, the SiO 2 On the film, a PZT film was formed to a thickness of 10 μm at a film formation temperature of 550° C. by sputtering to form a piezoelectric body 82. In this way, the nozzle plate 1 was formed. Next, the nozzle plate 1 was subjected to dry etching to form the nozzle holes 4 having a diameter of 25 μm.

[0039] Next, the various components are bonded together as shown in Fig. 4. The common liquid chamber plate 83 is made of Si, and a common liquid chamber 84 and a partition wall 85 are formed in the shapes shown in Figs. 1 and 4. A metal member is used for the ceiling plate 86, and a supply path 87 is formed. Next, the various components are bonded together to produce the liquid ejection head of Example 1 shown in Fig. 1. Furthermore, electrodes having a thickness of 0.1 µm are formed on the top and bottom of the piezoelectric body 82. When the amount of displacement of the nozzle plate 1 in the vicinity of the nozzle holes 4 of the obtained liquid ejection head was examined, the amount of nozzle displacement was 600 nm.

[0040] Next, as Comparative Example 1, a liquid ejection head shown in FIG. 5 and FIG. 6 was produced in the same manner as in Example 1, except that the film formation temperature in Example 1 was changed to 800°C.

[0041] Next, the ejection characteristics of the obtained liquid ejection head were evaluated by ejecting ink onto a medium under the following measurement conditions.

[0042] [Measurement conditions] Number of nozzles: 1024 nozzles Standard droplet volume: 5pl Drop speed: 7m / sec Distance between head and media: 1mm Ink type: Water-based pigment ink Ink viscosity: 5cp

[0043] The results are shown in Table 1. It can be seen that in this example, the variation in the ejection characteristics can be suppressed. In the table, the droplet volume (max-min) indicates the difference between the droplet volume [pl] at which the volume of a single droplet is maximum among the multiple nozzle holes in the liquid ejection head, and the droplet volume [pl] at which the volume of a single droplet is minimum. In addition, in the table, the droplet speed (max-min) indicates the difference between the droplet speed [m / sec] at which the ejection speed is maximum among the multiple nozzle holes in the liquid ejection head, and the droplet speed [m / sec] at which the ejection speed is minimum. In addition, the amount of bending 3σ indicates the average value within the liquid ejection head. For these, the smaller the value, the less the variation.

[0044] [Table 1]

[0045] An embodiment of the liquid ejection head and liquid ejection device obtained by the present invention will be described below. Fig. 7 is a cross-sectional explanatory diagram along a direction perpendicular to the nozzle arrangement direction of the liquid ejection head according to the embodiment (longitudinal direction of the pressure chambers), and Fig. 8 is a cross-sectional explanatory diagram along the nozzle arrangement direction of the liquid ejection head according to the embodiment.

[0046] The liquid ejection head 100 of this embodiment is formed by laminating and bonding a nozzle plate 1 having a piezoelectric body, a flow path plate 2 which is an individual flow path member, and a vibration plate member 3 which serves as a wall member. It also includes a common flow path member 20 which also serves as a frame member of the head. It may further include a piezoelectric actuator 11 which displaces a vibration region (vibration plate) 30 of the vibration plate member 3.

[0047] The nozzle plate 1 has a plurality of nozzles 4 for ejecting liquid.

[0048] The flow path plate 2 forms a plurality of pressure chambers 6 communicating with a plurality of nozzles 4, individual supply flow paths 7 which are individual flow paths communicating with each of the pressure chambers 6, and an intermediate supply flow path 8 which serves as a liquid introduction section communicating with one or more (one in this embodiment) individual supply flow paths 7.

[0049] The diaphragm member 3 has a plurality of displaceable diaphragms (vibration regions) 30 that form the wall surfaces of the pressure chambers 6 of the flow path plate 2. Here, the diaphragm member 3 has a two-layer structure (not limited to this) and is composed of a first layer 3A that forms a thin portion from the flow path plate 2 side and a second layer 3B that forms a thick portion.

[0050] A deformable vibration region 30 is formed in the first layer 3A, which is a thin portion, in a portion corresponding to the pressure chamber 6. Within the vibration region 30, a convex portion 30a, which is a thick portion that is bonded to the piezoelectric actuator 11, is formed in the second layer 3B.

[0051] A piezoelectric actuator 11 including an electromechanical conversion element is disposed on the opposite side of the diaphragm member 3 to the pressure chamber 6 as a driving means (actuator means, pressure generating means) for deforming the vibration area 30 of the diaphragm member 3.

[0052] This piezoelectric actuator 11 is formed by forming grooves by half-cut dicing in a piezoelectric member bonded onto a base member 13, and forming a required number of columnar piezoelectric elements 12 in a comb shape at specified intervals in the nozzle arrangement direction. The piezoelectric elements 12 are bonded to protruding portions 30a, which are thick portions formed in the vibration region 30 of the vibration plate member 3.

[0053] This piezoelectric element 12 is formed by alternately laminating piezoelectric layers and internal electrodes, with the internal electrodes being drawn out to the end faces and connected to external electrodes (end face electrodes), and flexible wiring member 15 being connected to the external electrodes.

[0054] The common flow path member 20 forms a common supply flow path 10 that communicates with the multiple pressure chambers 6. The common supply flow path 10 communicates with an intermediate supply flow path 8 that serves as a liquid introduction section via an opening 9 provided in the vibration plate member 3, and communicates with the individual supply flow paths 7 via the intermediate supply flow path 8.

[0055] In this liquid ejection head 100, for example, by lowering the voltage applied to the piezoelectric element 12 from a reference potential (intermediate potential), the piezoelectric element 12 contracts, the vibration area 30 of the vibration plate member 3 is pulled, and the volume of the pressure chamber 6 expands, causing liquid to flow into the pressure chamber 6.

[0056] Thereafter, the voltage applied to the piezoelectric element 12 is increased to expand the piezoelectric element 12 in the stacking direction, and the vibration region 30 of the vibration plate member 3 is deformed in the direction toward the nozzle 4, thereby contracting the volume of the pressure chamber 6, whereby the liquid in the pressure chamber 6 is pressurized and the liquid is ejected from the nozzle 4.

[0057] Fig. 9 is a cross-sectional explanatory diagram along a direction (longitudinal direction of pressure chambers) perpendicular to the nozzle arrangement direction of a liquid ejection head in still another embodiment.Fig. 10 is a schematic perspective view of the liquid ejection head of this embodiment.

[0058] The liquid ejection head 100 of this embodiment is a circulation type liquid ejection head, and is formed by laminating and bonding a nozzle plate 1, a flow path plate 2, and a vibration plate member 3 serving as a wall member. It also includes a piezoelectric actuator 11 that displaces a vibration region (vibration plate) 30 of the vibration plate member 3, and a common flow path member 20 that also serves as a frame member of the head.

[0059] The flow path plate 2 forms a plurality of pressure chambers 6 each connected to a plurality of nozzles 4 via a nozzle connecting passage 5, a plurality of individual supply flow paths 7 each connected to the plurality of pressure chambers 6 and also serving as fluid resistance sections, and one or more intermediate supply flow paths 8 serving as liquid introduction sections connected to two or more individual supply flow paths 7.

[0060] As in the above embodiment, the individual supply flow path 7 includes two flow path sections, a first flow path section 7A and a second flow path section 7B, which have a higher fluid resistance than the pressure chamber 6, and a third flow path section 7C, which is arranged between the first flow path section 7A and the second flow path section 7B and has a lower fluid resistance than the first flow path section 7A and the second flow path section 7B.

[0061] The flow path plate 2 is formed by stacking a plurality of plate-like members 2A to 2E, but is not limited to this.

[0062] In addition, the flow path plate 2 forms a plurality of individual recovery flow paths 57 along the surface direction of the flow path plate 2, each of which is connected to a plurality of pressure chambers 6 via a nozzle connecting passage 5, and an intermediate recovery flow path 58 which serves as one or more liquid discharge portions connected to two or more individual recovery flow paths 57.

[0063] The individual recovery flow path 57 includes two flow path sections, a first flow path section 57A and a second flow path section 57B, which have a higher fluid resistance than the pressure chamber 6, and a third flow path section 57C, which is disposed between the first flow path section 57A and the second flow path section 57B and has a lower fluid resistance than the first flow path section 57A and the second flow path section 57B. In the individual recovery flow path 57, a flow path section 57D, which is downstream of the second flow path section 57B in the circulation direction, has the same flow path width as the third flow path section 57C.

[0064] The common flow path member 20 forms a common supply flow path 10 and a common recovery flow path 50. In this embodiment, the common supply flow path 10 is composed of a flow path portion 10A that is aligned with the common recovery flow path 50 in the nozzle arrangement direction, and a flow path portion 10B that is not aligned with the common recovery flow path 50.

[0065] The common supply flow path 10 communicates with an intermediate supply flow path 8 serving as a liquid introduction portion through an opening 9 provided in the vibration plate member 3, and communicates with the individual supply flow paths 7 through the intermediate supply flow path 8. The common recovery flow path 50 communicates with an intermediate recovery flow path 58 serving as a liquid outlet portion through an opening 59 provided in the vibration plate member 3, and communicates with an individual recovery flow path 57 through the intermediate recovery flow path 58.

[0066] In addition, the common supply flow path 10 communicates with a supply port 71 , and the common recovery flow path 50 communicates with a recovery port 72 .

[0067] Other aspects such as the layer configuration of the diaphragm member 3 and the configuration of the piezoelectric actuator 11 are similar to those of the above embodiment.

[0068] In this liquid ejection head 100, as in the above embodiment, the piezoelectric element 12 is stretched in the stacking direction, and the vibration area 30 of the vibration plate member 3 is deformed in a direction toward the nozzle 4, thereby contracting the volume of the pressure chamber 6, thereby pressurizing the liquid in the pressure chamber 6 and ejecting the liquid from the nozzle 4.

[0069] Furthermore, liquid that is not ejected from the nozzles 4 passes through the nozzles 4, is recovered from the individual recovery flow paths 57 to the common recovery flow path 50, and is then re-supplied from the common recovery flow path 50 to the common supply flow path 10 via an external circulation path. Even when liquid is not being ejected from the nozzles 4, liquid circulates from the common supply flow path 10 to the common recovery flow path 50 via the pressure chambers 6, and is then re-supplied to the common supply flow path 10 via an external circulation path.

[0070] In this embodiment as well, the pressure fluctuations caused by liquid ejection can be attenuated and propagation to the common supply flow path 10 and the common recovery flow path 50 can be suppressed with a simple configuration.

[0071] Next, an example of a liquid ejection device obtained by the present invention will be described with reference to Figures 11 and 12. Figure 11 is a schematic explanatory diagram of the device, and Figure 12 is a plan explanatory diagram of an example of a head unit of the device.

[0072] This liquid ejection device, a printing device 500, is equipped with an input means 501 for inputting a continuous body 510, a guide and conveying means 503 for guiding and conveying the continuous body 510 such as continuous paper or sheet material inputted from the input means 501 to a printing means 505, the printing means 505 for ejecting liquid onto the continuous body 510 to print an image, a drying means 507 for drying the continuous body 510, and an ejection means 509 for ejecting the continuous body 510.

[0073] The continuous body 510 is sent out from the original winding roller 511 of the carrying-in means 501 , guided and transported by the rollers of the carrying-in means 501 , the guiding and transporting means 503 , the drying means 507 , and the carrying-out means 509 , and taken up by the take-up roller 591 of the carrying-out means 509 .

[0074] This continuous body 510 is transported in the printing means 505 on a transport guide member 559 opposite the head unit 550 and head unit 555, an image is formed by liquid ejected from the head unit 550, and post-processing is performed with processing liquid ejected from the head unit 555.

[0075] Here, in the head unit 550, for example, full line type head arrays 551A, 551B, 551C, and 551D for four colors (hereinafter, referred to as "head array 551" when no distinction is made between colors) are arranged from the upstream side in the transport direction.

[0076] Each head array 551 is a liquid ejection means, and ejects liquid of black K, cyan C, magenta M, and yellow Y onto the transported continuum 510. The types and number of colors are not limited to these.

[0077] Head array 551 is, for example, liquid ejection heads (also simply referred to as "heads") 100 according to the present invention arranged in a staggered pattern on base member 552, but is not limited to this.

[0078] The liquid ejection head and liquid ejection device obtained by the present invention may be configured to circulate liquid, for example, may be a liquid circulating device using a liquid ejection head. An example of a liquid circulating device will be described with reference to Fig. 13. Fig. 13 is a block diagram of the same circulating device. Note that, although only one head is shown here, when multiple heads are arranged, a supply side liquid path and a recovery side liquid path will be connected to the supply side and recovery side of the multiple heads, respectively, via a manifold or the like.

[0079] The liquid circulation device 600 is composed of a supply tank 601, a recovery tank 602, a main tank 603, a first liquid feed pump 604, a second liquid feed pump 605, a compressor 611, a regulator 612, a vacuum pump 621, a regulator 622, a supply side pressure sensor 631, and a recovery side pressure sensor 632.

[0080] Here, the compressor 611 and the vacuum pump 621 constitute a means for generating a pressure difference between the pressure in the supply tank 601 and the pressure in the recovery tank 602 .

[0081] The supply side pressure sensor 631 is located between the supply tank 601 and the head 100, and is connected to a supply side liquid path connected to the supply port 71 of the head 100. The recovery side pressure sensor 632 is located between the head 1 and the recovery tank 602, and is connected to a recovery side liquid path connected to the recovery port 72 of the head 100.

[0082] One side of the recovery tank 602 is connected to the supply tank 601 via a first liquid feed pump 604 , and the other side of the recovery tank 602 is connected to the main tank 603 via a second liquid feed pump 605 .

[0083] As a result, liquid flows into the head 100 from the supply tank 601 through the supply port 71, is recovered through the recovery port 72 to the recovery tank 602, and the liquid is sent from the recovery tank 602 to the supply tank 601 by the first liquid delivery pump 604, thereby forming a circulation path through which the liquid circulates.

[0084] Here, a compressor 611 is connected to the supply tank 601 and is controlled so that a supply side pressure sensor 631 detects a predetermined positive pressure. On the other hand, a vacuum pump 621 is connected to the recovery tank 602 and is controlled so that a recovery side pressure sensor 632 detects a predetermined negative pressure.

[0085] This allows liquid to be circulated through the head 100 while maintaining a constant negative pressure at the meniscus.

[0086] Furthermore, when liquid is discharged from the nozzles 4 of the head 100, the amount of liquid in the supply tank 601 and the recovery tank 602 decreases. Therefore, the second liquid feed pump 605 is used to replenish the recovery tank 602 with liquid from the main tank 603 as appropriate.

[0087] The timing of refilling the liquid from the main tank 603 to the recovery tank 602 can be controlled based on the detection results of a liquid level sensor installed in the recovery tank 602, such as refilling the liquid when the liquid level in the recovery tank 602 falls below a predetermined level.

[0088] Next, another example of a printing device as a liquid ejection device obtained by the present invention will be described with reference to Figures 14 and 15. Figure 14 is an explanatory plan view of the main part of the device, and Figure 15 is an explanatory side view of the main part of the device.

[0089] This printing device 500 is a serial type device, and a carriage 403 is reciprocated in the main scanning direction by a 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 hung between left and right side plates 491A, 491B to movably hold the carriage 403. The carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via a timing belt 408 hung between a drive pulley 406 and a driven pulley 407.

[0090] A liquid ejection unit 440, which integrates a liquid ejection head 100 and a head tank 441, is mounted on this carriage 403. The liquid ejection head 100 of the liquid ejection unit 440 ejects liquid of each color, for example, yellow (Y), cyan (C), magenta (M), and black (K). The liquid ejection head 100 is mounted with a nozzle row made up of a plurality of nozzles arranged in a sub-scanning direction perpendicular to the main scanning direction, and the ejection direction facing downward.

[0091] The liquid ejection head 100 is connected to the above-mentioned liquid circulation device 600, and liquid of a desired color is circulated and supplied.

[0092] The printing apparatus 500 includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

[0093] The conveyor belt 412 attracts the paper 410 and conveys it to a position facing the liquid ejection head 100. The conveyor belt 412 is an endless belt, and is stretched between a conveyor roller 413 and a tension roller 414. The paper can be attracted by electrostatic attraction or air suction.

[0094] The conveyor belt 412 moves in a circular motion in the sub-scanning direction as the conveyor rollers 413 are rotated by a sub-scanning motor 416 via a timing belt 417 and a timing pulley 418 .

[0095] Furthermore, a maintenance and recovery mechanism 420 for performing maintenance and recovery of the liquid ejection head 100 is disposed on one side of the conveyor belt 412 on one side of the carriage 403 in the main scanning direction.

[0096] The maintenance and recovery mechanism 420 is composed of, for example, a cap member 421 that caps the nozzle surface (surface on which nozzles are formed) of the liquid ejection head 100, a wiper member 422 that wipes the nozzle surface, and the like.

[0097] The main scanning movement mechanism 493, the maintenance and recovery mechanism 420, and the transport mechanism 495 are attached to a housing including side plates 491A and 491B and a back plate 491C.

[0098] In the printing device 500 configured in this manner, the paper 410 is fed onto the conveyor belt 412 and adsorbed thereon, and the paper 410 is conveyed in the sub-scanning direction by the circular movement of the conveyor belt 412.

[0099] Therefore, by driving the liquid ejection head 100 in response to an image signal while moving the carriage 403 in the main scanning direction, liquid is ejected onto the stationary paper 410 to form an image.

[0100] Next, an example of a liquid discharge unit using a liquid discharge head obtained by the present invention will be described with reference to Fig. 16. Fig. 16 is an explanatory plan view of the main part of the unit.

[0101] Of the components constituting the liquid ejection device, this liquid ejection unit 440 is composed of a housing portion constituted by side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, a carriage 403, and a liquid ejection head 100.

[0102] It is also possible to configure a liquid discharge unit in which the above-mentioned maintenance and recovery mechanism 420 is further attached to, for example, the side plate 491B of this liquid discharge unit 440.

[0103] Next, still another example of the liquid discharge unit will be described with reference to Fig. 17. Fig. 17 is a front explanatory view of the unit.

[0104] The liquid ejection unit 440 is composed of a liquid ejection head 100 to which a flow path part 444 is attached, and a tube 456 connected to the flow path part 444 .

[0105] The flow path part 444 is disposed inside the cover 442. A head tank 441 may be included instead of the flow path part 444. Furthermore, a connector 443 for electrically connecting with the liquid ejection head 100 is provided on the upper part of the flow path part 444.

[0106] In the present application, the liquid to be ejected may have a viscosity and surface tension that allows it to be ejected from the head, and is not particularly limited, but it is preferable that the viscosity of the liquid is 30 mPa·s or less at room temperature and pressure, or by heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, etc., containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a functionalizing material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, amino acids, proteins, or calcium, an edible material such as a natural colorant, etc., and these can be used for applications such as inkjet ink, surface treatment liquid, a liquid for forming a component of an electronic element or a light-emitting element, an electronic circuit resist pattern, a material liquid for three-dimensional modeling, etc.

[0107] Energy sources for ejecting liquid include piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a vibration plate and an opposing electrode.

[0108] A "liquid ejection unit" is a liquid ejection head integrated with functional parts and mechanisms, and includes a collection of parts related to ejecting liquid. For example, a "liquid ejection unit" includes a combination of a liquid ejection head and at least one of the following components: a head tank, a carriage, a supply mechanism, a maintenance and recovery mechanism, a main scanning movement mechanism, and a liquid circulation device.

[0109] Here, integration includes, for example, a liquid ejection head, a functional part, and a mechanism that are fixed to each other by fastening, bonding, engaging, etc., and one is held movably relative to the other. Also, the liquid ejection head, the functional part, and the mechanism may be configured to be detachable from each other.

[0110] For example, there are liquid ejection units in which the liquid ejection head and the head tank are integrated together, and there are also liquid ejection units in which the liquid ejection head and the head tank are integrated together by being connected to each other by a tube, etc. Here, a unit including a filter can be added between the head tank and the liquid ejection head of these liquid ejection units.

[0111] Furthermore, there is a liquid ejection unit in which the liquid ejection head and the carriage are integrated.

[0112] In some liquid ejection units, the liquid ejection head is movably supported by a guide member that constitutes a part of the scanning movement mechanism, and the liquid ejection head and the scanning movement mechanism are integrated together, and in some liquid ejection units, the liquid ejection head, the carriage, and the main scanning movement mechanism are integrated together.

[0113] Furthermore, there is a liquid ejection unit in which a cap member, which is part of the maintenance and recovery mechanism, is fixed to a carriage on which the liquid ejection head is attached, thereby integrating the liquid ejection head, carriage, and maintenance and recovery mechanism.

[0114] In addition, some liquid ejection units have a head tank or a liquid ejection head to which a flow path component is attached, and a tube is connected to the liquid ejection head, integrating the liquid ejection head with a supply mechanism. Liquid is supplied from a liquid storage source to the liquid ejection head via this tube.

[0115] The main scanning movement mechanism includes the guide member alone, and the supply mechanism includes the tube alone and the loading unit alone.

[0116] "Liquid ejection device" includes devices that have a liquid ejection head or a liquid ejection unit and eject liquid by driving the liquid ejection head. Liquid ejection devices include not only devices that can eject liquid onto objects to which the liquid can adhere, but also devices that eject liquid into air or liquid.

[0117] This "liquid ejecting device" can also include means for feeding, transporting, and discharging items onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0118] For example, examples of "devices that eject liquid" include image forming devices that eject ink to form an image on paper, and three-dimensional modeling devices that eject modeling liquid onto a powder layer formed by layering powder in order to create a three-dimensional object (a three-dimensional model).

[0119] In addition, the term "liquid ejection device" is not limited to devices that use ejected liquid to visualize meaningful images such as letters and figures. For example, it also includes devices that form patterns that have no meaning in themselves and devices that create three-dimensional images.

[0120] The above-mentioned "object to which liquid can adhere" means an object to which liquid can adhere at least temporarily, and to which the liquid adheres and sticks, or to which the liquid adheres and penetrates, etc. Specific examples include media such as paper, recording paper, film, cloth, and other recording media, electronic boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all objects to which liquid can adhere.

[0121] The material of the above-mentioned "object to which liquid can adhere" may be any material to which liquid can adhere even temporarily, such as paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, and ceramics.

[0122] Furthermore, the "liquid ejection device" may be a device in which a liquid ejection head and an object to which liquid can be attached move relatively, but is not limited to this. Specific examples include a serial type device in which a liquid ejection head moves, a line type device in which a liquid ejection head does not move, etc.

[0123] Other examples of "liquid ejecting devices" include a treatment liquid application device that ejects a treatment liquid onto paper to apply the treatment liquid to the surface of the paper for purposes such as modifying the surface of the paper, and an injection granulation device that ejects a composition liquid in which raw materials are dispersed through a nozzle to granulate fine particles of the raw materials.

[0124] In the present application, the terms image formation, recording, printing, imprinting, printing, modeling, and the like are all synonymous. [Explanation of symbols]

[0125] 1 Nozzle plate 1b, 1c Nozzle surface 4 Nozzle Holes 81 Substrate 82 Piezoelectric 83 Common liquid chamber plate 84 Common liquid chamber 85 Bulkhead 86 Ceiling Plate 87 Supply route 88 Ink

Prior Art Documents

Patent Documents

[0126]

Patent Document 1

Patent Document 2

Claims

1. A method for manufacturing a liquid ejection head that ejects liquid by vibrating a nozzle plate having a substrate and a piezoelectric body, comprising: a piezoelectric body forming step of forming the piezoelectric body on the substrate at 450° C. to 600° C.; a nozzle hole forming step of forming a nozzle hole penetrating the substrate and the piezoelectric body, The method for manufacturing a liquid ejection head, wherein the piezoelectric body forming step forms the piezoelectric body by a sputtering method or a CVD (Chemical Vapor Deposition) method.

2. 2. The method for manufacturing a liquid ejection head according to claim 1, wherein the piezoelectric body is made of PZT (lead zirconate titanate).

3. 3. The method for manufacturing a liquid ejection head according to claim 1, wherein the piezoelectric body forming step forms the piezoelectric body at a temperature of 450.degree. C. to 550.degree.

4. 4. The method for manufacturing a liquid ejection head according to claim 1, wherein the nozzle hole forming step forms the nozzle hole by dry etching.

5. 5. The method for manufacturing a liquid ejection head according to claim 1, further comprising, after the nozzle hole forming step, a bonding step of bonding a common liquid chamber substrate to the substrate side of the nozzle plate.

6. A method for manufacturing a liquid ejection device, comprising the steps of: manufacturing a liquid ejection device by using the method for manufacturing a liquid ejection head according to any one of claims 1 to 5.

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