Droplet ejection device and droplet ejection method

Abstract

To provide a droplet discharge device that can change a discharge pattern without replacing a multi-nozzle head.SOLUTION: A droplet discharge device of an embodiment of the present invention includes: an object holding part for holding an object; at least one first droplet discharge nozzle for discharging a first droplet; a second droplet discharge nozzle having a second distal end having a second inner diameter smaller than a first inner diameter of a first distal end in the first droplet discharge nozzle, for discharging a second droplet by using the first droplet discharged from the first droplet discharge nozzle; and a drive part that controls a relative positional relationship of the object held by the object holding part and the second droplet discharge nozzle and a relative position relationship of the first droplet discharge nozzle and the second droplet discharge nozzle.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a droplet ejection device and a droplet ejection method. [Background technology]

[0002] In recent years, inkjet printing technology has been applied to industrial processes. One example is the manufacturing process of color filters for liquid crystal displays. Conventionally, so-called piezo-type heads, which eject droplets using mechanical pressure or vibration, have been widely used in inkjet printing technology, but electrostatic ejection inkjet heads, which can eject finer droplets, are attracting attention. Patent Document 1 discloses an electrostatic ejection inkjet recording device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-34967 Summary of the Invention [Problem to be solved by the invention]

[0004] Recently, the development of simultaneous-discharge multi-nozzle heads has been progressing with the aim of improving productivity while maintaining the characteristics of electrostatic inkjet heads, which can eject fine droplets. Simultaneous-discharge multi-nozzle heads allow for flexible nozzle layout design. However, these heads have the drawback of only forming patterns with a predetermined nozzle layout. To form a different ejection pattern, a new multi-nozzle head with a different nozzle layout must be prepared. This poses challenges, such as the additional time required for setup and replacement of the multi-nozzle head. Meanwhile, conventional piezoelectric multi-nozzle heads with a fixed pitch have the following issues: (1) it is difficult to reduce the ejection volume in the first place; and (2) ejecting ink at locations other than the nozzle pitch requires raster scanning, rather than simultaneous ejection. This limits the pattern formation time due to the scanning speed.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a droplet ejection device that can change the ejection pattern without replacing the multi-nozzle head. [Means for solving the problem]

[0006] According to one embodiment of the present invention, there is provided a droplet ejection device including: an object holding unit for holding an object; at least one first droplet ejection nozzle for ejecting a first droplet; a plurality of second droplet ejection nozzles having a second tip portion with a second inner diameter smaller than a first inner diameter of a first tip portion of the first droplet ejection nozzle, for ejecting second droplets using the first droplets ejected from the first droplet ejection nozzle; and a drive unit for controlling the relative positional relationship between the object held in the object holding unit and the second droplet ejection nozzle, and the relative positional relationship between the first droplet ejection nozzle and the second droplet ejection nozzle.

[0007] In the droplet ejection device, each of the plurality of second droplet ejection nozzles may be connected to a plate portion having a through-hole with a third inner diameter larger than the second inner diameter.

[0008] In the droplet ejection device, the at least one first droplet ejection nozzle may include a plurality of first droplet ejection nozzles, and the distance between adjacent second droplet ejection nozzles may be smaller than the distance between adjacent first droplet ejection nozzles.

[0009] In the droplet ejection device, the first droplet ejection nozzle may be a piezoelectric nozzle, and the second droplet ejection nozzle may be an electrostatic ejection nozzle.

[0010] In the droplet ejection device, the plurality of second droplet ejection nozzles may be provided in a first direction and a second direction intersecting the first direction.

[0011] The droplet ejection device may further include an inspection unit that inspects the opening state of the second droplet ejection nozzle.

[0012] In the droplet ejection device, the second droplet ejection nozzle may be cleaned when a predetermined condition is satisfied.

[0013] According to one embodiment of the present invention, there is provided a droplet ejection method including: ejecting a first droplet from a first droplet ejection nozzle, thereby providing the first droplet to at least one of a plurality of second droplet ejection nozzles having a second tip end having a second inner diameter smaller than a first inner diameter of a first tip end of the first droplet ejection nozzle; and the second droplet ejection nozzle provided with the first droplet uses the first droplet to eject the second droplet onto a target object.

[0014] In the droplet ejection method, the first droplet ejection nozzle may be a piezoelectric nozzle, and the second droplet ejection nozzle may be an electrostatic ejection nozzle.

[0015] In the droplet ejection method, the second droplet ejection nozzle may be cleaned when a predetermined condition is satisfied. [Effects of the Invention]

[0016] By using one embodiment of the present invention, it is possible to provide a droplet ejection device that can change the ejection pattern without replacing the multi-nozzle head. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram of a droplet ejection device according to an embodiment of the present invention. [Figure 2] FIG. 1 is a plan view of a multi-nozzle head according to an embodiment of the present invention. [Figure 3] FIG. 1 is a perspective view of a droplet ejection nozzle according to an embodiment of the present invention. [Figure 4] 1A and 1B are a plan view and a cross-sectional view of a droplet ejection nozzle according to an embodiment of the present invention. [Figure 5] 1A to 1C are schematic diagrams illustrating a droplet ejection method according to an embodiment of the present invention. [Figure 6] 1A to 1C are schematic diagrams illustrating a droplet ejection method according to an embodiment of the present invention. [Figure 7] 1A to 1C are schematic diagrams illustrating a droplet ejection method according to an embodiment of the present invention. [Figure 8] 1A to 1C are schematic diagrams illustrating a droplet ejection method according to an embodiment of the present invention. [Figure 9] FIG. 1 is a plan view of a multi-nozzle head according to an embodiment of the present invention. [Figure 10] 1 is a schematic diagram of a droplet ejection device according to an embodiment of the present invention. [Figure 11] FIG. 2 is a schematic plan view of a formed pattern. [Figure 12] 1 is a schematic diagram of a droplet ejection device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, each embodiment of the invention disclosed in this application will be described with reference to the drawings. However, the present invention can be embodied in various forms without departing from the spirit of the invention, and should not be construed as being limited to the description of the embodiments exemplified below.

[0019] In the drawings referred to in this embodiment, identical parts or parts having similar functions are given the same or similar symbols (symbols consisting of a number followed by A, B, or -1, -2, etc.), and repeated explanations may be omitted. Also, for convenience of explanation, the dimensional ratios in the drawings may differ from the actual ratios, and some components may be omitted from the drawings.

[0020] Furthermore, in the detailed description of the present invention, when defining the positional relationship between a certain component and another component, "above" and "below" do not only mean being located directly above or directly below a certain component, but also include cases where there are other components interposed between them, unless otherwise specified.

[0021] First Embodiment (1-1. Configuration of the droplet ejection device 100) FIG. 1 is a schematic diagram of a droplet ejection device 100 according to one embodiment of the present invention.

[0022] The droplet ejection device 100 includes a control unit 110 , a memory unit 115 , a power supply unit 120 , a drive unit 130 , an ink tank 135 , a first droplet ejection unit 140 , a second droplet ejection unit 150 , and a target holding unit 160 .

[0023] The control unit 110 includes a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or other arithmetic processing circuit. The control unit 110 controls the discharge process of the first droplet discharge unit 140 using a preset droplet discharge program.

[0024] The storage unit 115 functions as a database that stores a droplet ejection program and various information used in the droplet ejection program. The storage unit 115 is implemented by a memory, an SSD, or a memory-capable element.

[0025] The power supply unit 120 is connected to the control unit 110, the memory unit 115, the drive unit 130, the ink tank 135, the first droplet ejection unit 140, the second droplet ejection unit 150, and the target holding unit 160. The power supply unit 120 applies a voltage to the first droplet ejection unit 140 and the second droplet ejection unit 150 based on a signal input from the control unit 110. In this example, the power supply unit 120 applies a pulsed voltage to the first droplet ejection unit 140 and the second droplet ejection unit 150. Note that the voltage is not limited to a pulsed voltage, and a constant voltage may be applied all the time. The voltage applied to the first droplet ejection unit 140 from the power supply unit 120 causes a first droplet 147 to be ejected from a tip 141a of a first droplet ejection nozzle 141 (described later) in the direction of the target 200 (third direction D3). Similarly, a voltage applied to the second droplet ejection section 150 from the power supply section 120 causes the second droplet 157 to be ejected in the direction of the target object 200 (third direction D3) from the second droplet ejection nozzle 153 (tip 153a) provided in the multi-nozzle head 151 of the second droplet ejection section 150 described later.

[0026] The drive unit 130 is composed of drive members such as a motor, a belt, and gears. Based on instructions from the control unit 110, the drive unit 130 moves the first droplet discharge unit 140 (first droplet discharge nozzle 141) and the second droplet discharge unit 150 (more specifically, the multi-nozzle head 151) relative to the target object holder 160 (in the second direction D2 in this example). In this way, the drive unit 130 controls the relative positional relationship between the target object 200 and the multi-nozzle head 151 (second droplet discharge nozzle 153) and the relative positional relationship between the first droplet discharge nozzle 141 and the multi-nozzle head 151 (second droplet discharge nozzle 153) when the device is in use (when discharging droplets).

[0027] The driving unit 130 may suitably fix the first droplet discharge unit 140 (first droplet discharge nozzle 141) and the second droplet discharge unit 150 (multi-nozzle head 151) and move the target object 200. The driving unit 130 may also be used in combination with a goniostage to finely adjust the first droplet discharge nozzle 141 and the multi-nozzle head 151 (second droplet discharge nozzle 153).

[0028] The object holder 160 has a function of holding the object 200. In this example, a stage is used as the object holder 160. There are no particular restrictions on the mechanism by which the object holder 160 holds the object 200, and a general holding mechanism is used. In this example, the object 200 is vacuum-adsorbed to the object holder 160. However, the present invention is not limited to this, and the object holder 160 may hold the object 200 using a fixture.

[0029] The target object 200 refers to a member onto which droplets are discharged from the droplet discharge unit. In this example, a glass plate is used as the target object 200. However, the target object 200 is not limited to a glass plate. For example, it may be a metal plate or an organic resin member. Furthermore, metal wiring or an organic resin member may be formed on the target object 200. Furthermore, a counter electrode for droplet discharge may be provided on the target object 200. At this time, a GND potential may be applied to the target object 200.

[0030] (1-2. Configuration of the first droplet ejection unit 140) The first droplet discharge unit 140 is disposed above the target object 200 (target object holding unit 160) and the second droplet discharge unit 150 when discharged by the drive unit 130. The first droplet discharge unit 140 includes a first droplet discharge nozzle 141 and a piezoelectric element 145 for discharging droplets (first droplets 147). In this example, a piezoelectric inkjet nozzle is used for the first droplet discharge nozzle 141. The piezoelectric element 145 is provided above the first droplet discharge nozzle 141, but the location of the piezoelectric element 145 may be changed as appropriate. The piezoelectric element 145 is electrically connected to the power supply unit 120. The piezoelectric element 145 applies pressure to the liquid supplied from the ink tank 135 by a voltage applied from the power supply unit 120, thereby discharging the first droplet 147 from a tip 141a (also referred to as a first tip) of the first droplet discharge nozzle 141.

[0031] The first droplet discharge nozzle 141 of the first droplet discharge unit 140 is provided perpendicular to the surface of the target object 200 (the upper surface of the target object holder 160).

[0032] (1-3. Configuration of the second droplet ejection unit 150) The second droplet discharge unit 150 is disposed above the target object 200 (target object holding unit 160) by the drive unit 130 when discharging droplets. The first droplet discharge unit 140 is disposed above the second droplet discharge unit 150 when discharging droplets. Therefore, the second droplet discharge unit 150 is disposed between the first droplet discharge unit 140 and the target object 200 (target object holding unit 160) when discharging droplets. The second droplet discharge unit 150 may be partially connected to or fixed to the first droplet discharge unit 140. The second droplet discharge unit 150 includes a multi-nozzle head 151.

[0033] The multi-nozzle head 151 is used while being fixed to a mount and an attachment (not shown). The multi-nozzle head 151 is provided with a plurality of second droplet discharge nozzles 153 for discharging droplets (second droplets 157). The second droplet discharge nozzles 153 are electrostatic discharge type inkjet nozzles. Details of the multi-nozzle head 151 will be described below.

[0034] (1-4. Configuration of multi-nozzle head 151) Fig. 2 is a plan view of the multi-nozzle head 151. Fig. 3 is a perspective view of the second droplet discharge nozzle 153. Fig. 4(A) is a top view of the second droplet discharge nozzle 153. Fig. 4(B) is a cross-sectional view of the second droplet discharge nozzle 153 taken along line A1-A2.

[0035] As shown in FIG. 2, the multi-nozzle head 151 includes a plate portion 152 and a second droplet ejection nozzle 153 .

[0036] The plate portion 152 is provided in a plate shape. In this example, the plate portion 152 extends in the first direction D1. Metal materials such as nickel, copper, and stainless steel are used for the plate portion 152, but the material may be changed as appropriate as long as it is usable when an electric potential can be applied. The thickness of the plate portion 152 is set appropriately. In this example, the thickness of the plate portion 152 is 10 μm or more and 100 μm or less.

[0037] As shown in FIGS. 3 and 4, the second droplet discharge nozzle 153 is connected to one surface (lower surface) of the plate portion 152 at its upper portion. The multi-nozzle head 151 includes a plurality of second droplet discharge nozzles 153. The second droplet discharge nozzles 153 are arranged side by side in the first direction D1. In this embodiment, second droplet discharge nozzles 153-1, 153-2, . . . , 153-(N-1), and 153-N are provided on the plate portion 152, where N is a natural number equal to or greater than 3. Note that when there is no need to separately describe the second droplet discharge nozzles 153-1, 153-2, . . . , 153-(N-1), and 153-N, they will be referred to as the second droplet discharge nozzles 153. The second droplet discharge nozzles 153 are made of a metal material such as nickel or copper, but may be made of any material suitable for application of an electric potential. The second droplet discharge nozzles 153 have a tapered shape. In this example, the distance D1 between adjacent second droplet discharge nozzles 153 (the distance between the second droplet discharge nozzle 153-1 and the second droplet discharge nozzle 153-2) is 200 μm.

[0038] The plate portion 152 has a through-hole 152o in a portion corresponding to (overlapping with) the second droplet ejection nozzle 153, the through-hole 152o having an inner diameter r152o (also referred to as a third inner diameter) larger than the inner diameter r153a (also referred to as a second inner diameter) of the ejection port of the second droplet ejection nozzle 153 (opening 153ao of the tip portion 153a of the second droplet ejection nozzle 153). The inner diameter of the through-hole of the plate portion 152 may be 1 μm or more and 100 μm or less. The inner diameter of the tip portion 153a of the second droplet ejection nozzle 153 may be several hundred nanometers or more and 50 μm or less, preferably 1 μm or more and 30 μm or less, and more preferably 5 μm or more and 20 μm or less. In this embodiment, a voltage may be applied to the second droplet ejection nozzle 153, a voltage may be applied to the plate portion 152, or a voltage may be applied to the ink stored in the second droplet ejection nozzle 153. When a voltage is applied to the plate portion 152 and the second droplet ejection nozzle 153, an electrode may be provided. The electrode may be made of tungsten, nickel, molybdenum, titanium, gold, silver, copper, platinum, or the like. In this case, a plurality of electrodes may be provided so that the voltage is applied uniformly to the entire plate portion 152. Furthermore, although the present embodiment shows an example in which a voltage is applied to the second droplet ejection nozzle 153, the plate portion 152, or the ink, a voltage may also be applied to a jig (for example, a mount or attachment) that holds the multi-nozzle head 151.

[0039] The inner diameter r153a (second inner diameter) of the discharge port (tip portion 153a) of the second droplet discharge nozzle 153 is smaller than the inner diameter (also referred to as the first inner diameter) of the discharge port (tip portion 141a) of the first droplet discharge nozzle 141. Therefore, the discharge amount per unit time of the second droplet discharge nozzle 153 is smaller than the discharge amount per unit time of the first droplet discharge nozzle 141.

[0040] Furthermore, in this embodiment, the second droplet ejection section 150 is not connected to the ink tank 135. When ejecting droplets, the first droplet ejection section 140 (first droplet ejection nozzle 141) moves above the second droplet ejection section 150 (multi-nozzle head 151) by the control section 110 and the drive section 130. That is, in this embodiment, the ejection position can be controlled based on the relative positional relationship between the first droplet ejection nozzle 141 and the multi-nozzle head 151 including a plurality of second droplet ejection nozzles.

[0041] (1-5.Droplet discharge method) Next, a droplet ejection method according to this embodiment will be described. Figures 5 to 8 are schematic diagrams showing the droplet ejection method.

[0042] First, the first droplet ejection section 140 is moved to a predetermined position in the first direction D1 by the control section 110 and the drive section 130. At this time, the first droplet ejection section 140 (first droplet ejection nozzle 141) is placed at a predetermined position on the multi-nozzle head 151 of the second droplet ejection section 150. Next, as shown in Fig. 5, the first droplet ejection nozzle 141 ejects the liquid held in the ink tank 135 as a first droplet 147 in the third direction D3 (specifically, downward) to a predetermined position above the multi-nozzle head 151 by a voltage applied from the power supply section 120.

[0043] The ejected first droplets 147 are provided to predetermined second droplet ejection nozzles 153 and temporarily stored. As shown in FIG. 6, the first droplet ejection unit 140 repeats the above process. As a result, the first droplets 147 are provided (stored) in some of the multiple second droplet ejection nozzles 153. At this time, in this embodiment, the second droplet ejection nozzles 153 are connected to the plate unit 152 on the upper side. The plate unit 152 has a through-hole with a larger inner diameter than the second droplet ejection nozzles 153. As a result, it can be said that the second droplet ejection nozzles 153 have a structure that makes it easy to store first droplets.

[0044] Next, the power supply unit 120 applies a pulsed voltage (in this example, 1000 V with the target (GND potential) as a reference) to the second droplet discharge unit 150 (multi-nozzle head 151) based on control from the control unit 110. As a result, as shown in FIG. 7, the second droplet discharge nozzle 153 simultaneously discharges second droplets 157 using the first droplets 147 (a part of the first droplets 147) provided to the second droplet discharge nozzle 153. As a result, a discharge pattern by the second droplets 157 is formed on the target 200, as shown in FIG. 8.

[0045] In this embodiment, even though the second droplet ejection unit 150 has a multi-nozzle head including multiple electrostatic droplet ejection nozzles, the second droplet ejection unit 150 is not directly connected to the ink tank. This limits the simultaneous ejection of droplets from all of the second droplet ejection nozzles. Only the first droplet ejection unit 140 is connected to the ink tank 135. In this embodiment, when forming an ejection pattern, the position from which droplets are to be ejected is controlled by moving the first droplet ejection unit 140, and the size of the droplets is controlled by the second droplet ejection unit 150.

[0046] Therefore, by using this embodiment, it is possible to change the discharge pattern without replacing the multi-nozzle head. Also, in the case of this embodiment, a pattern can be formed on a target object using small-diameter droplets discharged from the electrostatic discharge nozzle. In other words, by using this embodiment, it is possible to form a desired discharge pattern with high precision.

[0047] Second Embodiment In this embodiment, a second droplet ejection unit (multi-nozzle head) different from that in the first embodiment will be described. Specifically, an example in which second droplet ejection nozzles are arranged two-dimensionally will be described. For convenience of explanation, some components will be omitted.

[0048] (2-1. Configuration of multi-nozzle head 151A) Fig. 9 is a plan view of the multi-nozzle head 151A in the second droplet ejection section 150A. As shown in Fig. 9, the multi-nozzle head 151A includes a plate section 152 and a second droplet ejection nozzle 153A.

[0049] A plurality of second droplet discharge nozzles 153A are provided on one surface of the plate portion 152. The second droplet discharge nozzles 153A are arranged at equal intervals in a first direction D1 and a second direction D2 that intersects with the first direction D1 (in this example, perpendicular to it). In this example, the multi-nozzle head 151A includes 3 rows x 13 columns = 39 droplet discharge nozzles. The number of second droplet discharge nozzles 153 arranged can be changed as appropriate. For example, it may be 4 rows x 100 columns = 400 nozzles, or 1,000 rows x 1,000 columns = 1,000,000 nozzles.

[0050] In this embodiment, even though the second droplet ejection unit 150A has a multi-nozzle head including a plurality of electrostatic droplet ejection nozzles arranged two-dimensionally, the second droplet ejection unit 150A is not directly connected to the ink tank 135. This limits the simultaneous ejection of droplets from all of the second droplet ejection nozzles 153. In this case, only the first droplet ejection unit 140 is connected to the ink tank 135. In this embodiment, when forming an ejection pattern, the position from which droplets are to be ejected is controlled by moving the first droplet ejection unit 140, and the size of the droplets is controlled by the second droplet ejection unit 150A.

[0051] Therefore, by using this embodiment, it is possible to change the discharge pattern without replacing the multi-nozzle head. Also, by discharging droplets using an electrostatic droplet discharge nozzle, it is possible to form a desired discharge pattern with high precision.

[0052] In this embodiment, the second droplet discharge nozzles 153A are arranged side by side at equal intervals in the first direction D1 and the second direction D2, but the present invention is not limited to this. For example, the second droplet discharge nozzles 153A may be arranged with a stagger (zigzag) in the second direction, or the intervals between adjacent second droplet discharge nozzles 153A may be different.

[0053] Third Embodiment In this embodiment, a droplet ejection device different from the first and second embodiments will be described. Specifically, an example in which a plurality of first droplet ejection nozzles are provided will be described. For convenience of explanation, some components will be omitted.

[0054] 10 is a schematic diagram of a droplet ejection device 100B. As shown in Fig. 10, the droplet ejection device 100B includes a control unit 110, a memory unit 115, a power supply unit 120, a drive unit 130, a first droplet ejection unit 140B, a second droplet ejection unit 150B, and a target object holder 160.

[0055] The first droplet discharge section 140B includes a plurality of first droplet discharge nozzles 141B. In this example, two first droplet discharge nozzles 141B are arranged side by side in the first direction D1. Note that each first droplet discharge nozzle 141B may be controlled to move and discharge independently. Also, the number of first droplet discharge nozzles 141B may be changed as appropriate.

[0056] In this embodiment, the distance D1 between adjacent first droplet ejection nozzles 141B (more specifically, the tip portions 141Ba of the first droplet ejection nozzles 141B) is greater than the distance D2 between adjacent second droplet ejection nozzles 153B (more specifically, the tip portions 153Ba of the second droplet ejection nozzles 153B).

[0057] The second droplet discharge nozzles 153B of the second droplet discharge section 150B may be arranged in the first direction D1 and the second direction D2, similar to the second droplet discharge nozzles 153A.

[0058] In this embodiment, an example has been shown in which two first droplet discharge nozzles 141B are arranged side by side in the first direction D1, but the present invention is not limited to this. Three or more first droplet discharge nozzles 141B may be provided, and adjacent first droplet discharge nozzles 141B may be arranged side by side in a direction intersecting the first direction D1.

[0059] FIG. 11 is a plan view of a pattern formed using the first droplet discharge unit 140B and the second droplet discharge unit 150B. As shown in FIG. 11, a pattern 190 formed by second droplets 157 is provided on a target object 200. In this embodiment, the first droplet discharge unit 140B and the second droplet discharge unit 150B are used in combination. At this time, the first droplet discharge nozzles 141B of the first droplet discharge unit 140B move two-dimensionally to desired positions on the multi-nozzle head 151B. By discharging droplets from each of the first droplet discharge nozzles 141B at once, a complex desired pattern can be formed in a short time without replacing the multi-nozzle head.

[0060] In this embodiment, the first droplet discharge section 140B may discharge (also referred to as drawing) droplets onto the second droplet discharge section 150B at the timing when the substrate is transported or when the substrate is aligned.

[0061] In conventional cases, the droplet discharge (drawing) process begins after the substrate transport and alignment operations are completed. On the other hand, in this embodiment, the process time (substrate transport and alignment) can be allocated to the first droplet discharge process. Therefore, immediately after substrate alignment, droplets can be discharged simultaneously from the second droplet discharge unit 150B. As a result, extremely high-speed drawing is possible.

[0062] Therefore, by using this embodiment, it is possible to form a desired ejection pattern with high precision using an electrostatic ejection type multi-nozzle head, and it is possible to perform high-speed drawing that eliminates wasted time, and it is also possible to form more complex ejection patterns.

[0063] <Fourth embodiment> In this embodiment, a droplet ejection device different from the first to third embodiments will be described. Specifically, a droplet ejection device having an inspection unit will be described. For convenience of explanation, some members will be omitted.

[0064] Fig. 12 is a schematic diagram of the droplet ejection device 100C. As shown in Fig. 12, the droplet ejection device 100C includes a control unit 110, a memory unit 115, a power supply unit 120, a drive unit 130, a first droplet ejection unit 140, a second droplet ejection unit 150, and a target object holder 160, as well as an inspection unit 170.

[0065] The inspection unit 170 may inspect the tip 153a of the second droplet discharge nozzle 153 before discharging droplets. A CMOS image sensor may be used for the inspection unit 170. Some of the droplets discharged from the first droplet discharge unit 140 may remain in the second droplet discharge nozzle 153 of the second droplet discharge unit 150. When the inspection unit 170 inspects the second droplet discharge unit 150 for the second droplet 157, if the tip 153a of the second droplet discharge nozzle 153 satisfies a predetermined condition, the second droplet discharge nozzle 153 may be subjected to a cleaning process. In this case, the predetermined condition may be a blockage rate of the tip 153a of 30% or more. An organic solvent may be used to clean the second droplet discharge nozzle 153.

[0066] By using this embodiment, the second droplets 157 can be stably ejected from the second droplet ejection section.

[0067] (Variation) Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the scope of the present invention. For example, to the above-described embodiments, a person skilled in the art may appropriately add or delete components, combine or change the design of the embodiments, or add or omit processing or change conditions, and these modifications and alterations are also included within the scope of the present invention as long as they maintain the gist of the present invention.

[0068] In the first embodiment of the present invention, an example has been shown in which the ejected first droplet 147 is provided to a predetermined second droplet ejection nozzle 153 and temporarily stored, but the present invention is not limited to this. By controlling the timing of voltage application to the multi-nozzle head 151, the second droplet 157 may be ejected without being stored after being provided to the second droplet ejection nozzle 153. Specifically, voltage may be applied to the first droplet ejection nozzle 141 and the second droplet ejection nozzle 153 simultaneously.

[0069] In the first embodiment of the present invention, an example has been shown in which the first droplet discharge unit 140 is disposed on the target object 200 (target object holder 160) and the second droplet discharge unit 150, but the present invention is not limited to this. The first droplet discharge unit 140 may discharge the first droplets 147 onto the target object 200 without passing through the second droplet discharge unit 150 (multi-nozzle head 151). This makes it possible to form a high-resolution pattern on the target object 200 as well as a pattern with large droplet size.

[0070] In the first embodiment of the present invention, an example has been shown in which the plurality of second droplet ejection nozzles 153 eject droplets simultaneously, but the present invention is not limited to this. The droplets may be ejected sequentially in multiple batches.

[0071] Furthermore, in the first embodiment of the present invention, an example has been shown in which the second droplet 157 is ejected after ejection from several second droplet ejection nozzles 153, but the present invention is not limited to this. For example, one first droplet 147 may be ejected and stored in the second droplet ejection nozzle 153, and then the second droplet 157 may be ejected. The timing of ejecting the first droplet and the second droplet may be controlled as appropriate.

[0072] Furthermore, in the first embodiment of the present invention, an example was shown in which the first droplet discharge nozzle 141 and the multi-nozzle head 151 (second droplet discharge nozzle 153) were positioned above the target object to discharge droplets, but the present invention is not limited to this. For example, when discharging the first droplet 147, the first droplet discharge nozzle 141 and the multi-nozzle head 151 (second droplet discharge nozzle 153) do not have to be positioned above the target object 200. Furthermore, when discharging the second droplet 157, the first droplet discharge nozzle 141 does not have to be positioned above the multi-nozzle head 151 (second droplet discharge nozzle 153) and the target object 200. [Explanation of symbols]

[0073] 100 droplet ejection device, 110 control unit, 115 memory unit, 120 power supply unit, 130 drive unit, 135 ink tank, 140 first droplet ejection unit, 141 first droplet ejection nozzle, 141a tip unit, 145 piezoelectric element, 147 first droplet, 150 second droplet ejection unit, 151 multi-nozzle head, 151o through-hole, 152 plate unit, 153 second droplet ejection nozzle, 153a tip unit, 153ao opening unit, 157 second droplet, 160 object holding unit, 170 inspection unit, 190 pattern, 200 object

Claims

1. an object holder for holding an object; at least one first droplet ejection nozzle for ejecting a first droplet; a plurality of second droplet ejection nozzles each having a second tip portion with a second inner diameter smaller than a first inner diameter of the first tip portion of the first droplet ejection nozzle, for ejecting a second droplet using the first droplet ejected from the first droplet ejection nozzle; a drive unit that controls a relative positional relationship between the target held by the target holding unit and the second droplet discharge nozzle, and a relative positional relationship between the first droplet discharge nozzle and the second droplet discharge nozzle, the first droplet ejection nozzle is a piezoelectric nozzle, the second droplet ejection nozzle is an electrostatic ejection nozzle; Droplet ejection device.

2. each of the plurality of second droplet ejection nozzles is connected to a plate portion having a through-hole with a third inner diameter larger than the second inner diameter; The droplet ejection device according to claim 1 .

3. the at least one first droplet ejection nozzle includes a plurality of first droplet ejection nozzles; the distance between adjacent second droplet ejection nozzles is smaller than the distance between adjacent first droplet ejection nozzles; The droplet ejection device according to claim 1 or 2.

4. the plurality of second droplet ejection nozzles are arranged in a first direction and a second direction intersecting the first direction; The droplet ejection device according to claim 1 .

5. further comprising an inspection unit that inspects the opening state of the second droplet ejection nozzle; The droplet ejection device according to claim 1 .

6. the second droplet ejection nozzle is cleaned when a predetermined condition is satisfied; The droplet ejection device according to claim 5 .

7. discharging a first droplet from a first droplet discharge nozzle to provide the first droplet to at least one of a plurality of second droplet discharge nozzles, the second droplet discharge nozzle having a second tip portion with a second inner diameter smaller than a first inner diameter of the first tip portion of the first droplet discharge nozzle; the second droplet ejection nozzle, to which the first droplet has been provided, ejects a second droplet onto a target object using the first droplet; the first droplet ejection nozzle is a piezoelectric nozzle, the second droplet ejection nozzle is an electrostatic ejection nozzle; Droplet ejection method.

8. the second droplet ejection nozzle is cleaned when a predetermined condition is satisfied; The droplet ejection method according to claim 7 .

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