Nozzle head, manufacturing method thereof, and droplet ejection device

Abstract

To provide a multi-nozzle with high discharge uniformity, and a drop discharge device comprising the multi-nozzle.SOLUTION: A nozzle head comprises: a plate part provided in a plate-shape; a drop discharge nozzle which is provided on the plate part, and includes a plurality of drop discharge nozzles for discharging drops according to an electrostatic discharge method; and a pseudo nozzle part which is provided on the plate part and provided in the periphery of the drop discharge nozzle part, and includes a plurality of pseudo nozzles. In the nozzle head, the plurality of drop discharge nozzles are provided in an array in a first direction, and the pseudo nozzle part may be provided on both sides of the drop discharge nozzle part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a nozzle head, a method for manufacturing a nozzle head, and a droplet ejection device. [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 multi-nozzles for electrostatic inkjet heads has been progressing from the viewpoint of improving productivity. However, with multi-nozzles, there is a risk that the diameter of each nozzle will be uneven. If the diameter of each nozzle is uneven, it will be impossible to eject droplets uniformly onto the target. As a result, it is difficult to form a uniform image.

[0005] Therefore, an object of the present invention is to provide a multi-nozzle with high ejection uniformity and a droplet ejection device having the multi-nozzle. [Means for solving the problem]

[0006] According to one embodiment of the present invention, there is provided a nozzle head including: a plate portion having through holes; a droplet discharge nozzle portion including a plurality of droplet discharge nozzles disposed corresponding to the through holes of the plate portion and configured to discharge droplets by an electrostatic discharge method; and a pseudo-nozzle portion disposed around the droplet discharge nozzle portion of the plate portion and including a plurality of pseudo-nozzles with closed tips.

[0007] In the nozzle head, the plurality of droplet discharge nozzles may be arranged side by side in a first direction, and the pseudo-nozzle portions may be provided on both sides of the droplet discharge nozzle portions in the first direction.

[0008] In the nozzle head, the plurality of pseudo-nozzles may be provided over an entire range of 1 mm to 5 mm in the first direction from the pseudo-nozzle arranged on the outermost side.

[0009] In the nozzle head, the pseudo-nozzle section may include five or more pseudo-nozzles on both sides of the droplet ejection nozzle section in the first direction.

[0010] In the nozzle head, a first distance between adjacent droplet ejection nozzles may be the same as a second distance between adjacent pseudo-nozzles.

[0011] In the nozzle head, the plurality of droplet ejection nozzles may be arranged in a first direction and a second direction intersecting the first direction, and the pseudo-nozzle portion may be arranged to surround the droplet ejection nozzle portion.

[0012] In the nozzle head, the pseudo-nozzles may be arranged side by side on both sides in the first direction and on both sides in the second direction so as to correspond to each of the droplet ejection nozzles arranged on the outside among the plurality of droplet ejection nozzles, and the number of the pseudo-nozzles in each row arranged on one side in the first direction and one side in the second direction may be 2 or more and 30 or less.

[0013] In the nozzle head, the pseudo nozzle may have a frame shape.

[0014] In the nozzle head, a first height from the plate portion to the tip of the pseudo-nozzle may be lower than a second height from the plate portion to the tip of the droplet ejection nozzle.

[0015] According to one embodiment of the present invention, there is provided a droplet ejection device including the nozzle head described above.

[0016] According to one embodiment of the present invention, there is provided a method for manufacturing a nozzle head, comprising: preparing a master mold having a first surface and a second surface opposite the first surface, a first recess group having a plurality of first recesses on the first surface side, and a second recess group having a plurality of second recesses arranged around the first recess group; forming a plurality of first structures having open tips in the first recesses, forming a plurality of second structures having closed tips in the second recesses, and forming a planar third structure on the first surface; forming a resist mask so as to shield the plurality of first structures and the plurality of second structures; forming a fourth structure on the third structure; removing the resist mask; and releasing the first structures, the second structures, the third structures, and the fourth structures from the master mold, thereby forming a droplet ejection nozzle from the first structure, forming a pseudo-nozzle from the second structure, and forming a plate portion from the third structure and the fourth structure.

[0017] In the nozzle head, the insulating layer may be exposed at the bottom of the first recess.

[0018] In the nozzle head, the plurality of droplet ejection nozzles may be formed side by side in a first direction, and the plurality of pseudo-nozzles may be formed on both sides of the droplet ejection nozzles in the first direction.

[0019] In the nozzle head, the plurality of pseudo-nozzles may be formed over an entire range of 1 mm to 5 mm in the first direction from the pseudo-nozzle arranged on the outermost side.

[0020] In the nozzle head, five or more of the pseudo nozzles may be formed on both sides of the droplet ejection nozzle.

[0021] In the nozzle head, a first distance between adjacent droplet ejection nozzles may be the same as a second distance between adjacent pseudo-nozzles.

[0022] In the nozzle head, the plurality of droplet ejection nozzles may be arranged in a first direction and a second direction intersecting the first direction, and the pseudo-nozzles may be formed so as to surround the droplet ejection nozzles.

[0023] In the nozzle head, the pseudo nozzles are formed in a row on both sides in the first direction and on both sides in the second direction so as to correspond to each of the droplet ejection nozzles formed on the outside among the plurality of droplet ejection nozzles, and the number of the pseudo nozzles formed in each row on one side in the first direction and one side in the second direction may be 2 or more and 30 or less.

[0024] In the nozzle head, the pseudo nozzle may be formed to have a frame shape. [Effects of the Invention]

[0025] By using one embodiment of the present invention, it is possible to provide a multi-nozzle with high discharge uniformity and a droplet discharge device having the multi-nozzle. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic diagram of a droplet ejection device according to an embodiment of the present invention. [Figure 2] 1A and 1B are a plan view and a cross-sectional view of a nozzle head according to an embodiment of the present invention; [Figure 3] FIG. 2 is an enlarged plan view of a nozzle head according to an embodiment of the present invention. [Figure 4] FIG. 1 is a perspective view of a droplet ejection nozzle according to an embodiment of the present invention. [Figure 5] 1A and 1B are a top view and a cross-sectional view of a droplet ejection nozzle according to an embodiment of the present invention. [Figure 6] FIG. 1 is a perspective view of a pseudo-nozzle according to an embodiment of the present invention. [Figure 7] 1A and 1B are a top view and a cross-sectional view of a pseudo-nozzle according to an embodiment of the present invention; [Figure 8] FIG. 2 is a manufacturing flow diagram of a nozzle head according to an embodiment of the present invention. [Figure 9] FIG. 2 is a manufacturing flow diagram of a nozzle head according to an embodiment of the present invention. [Figure 10] 1A and 1B are a plan view and a cross-sectional view of a nozzle head according to an embodiment of the present invention; [Figure 11] 1A and 1B are a plan view and a cross-sectional view of a nozzle head according to an embodiment of the present invention; [Figure 12] 1A and 1B are a top view and a cross-sectional view of a pseudo-nozzle according to an embodiment of the present invention; [Figure 13] 1A and 1B are a top view and a cross-sectional view of a pseudo-nozzle according to an embodiment of the present invention; [Figure 14] 1 is an electron microscope photograph of a droplet ejection nozzle in a nozzle head manufactured using an embodiment of the present invention. [Figure 15] 1 is an optical microscope photograph of droplets ejected using the nozzle head of Example 1. [Figure 16] 1 is a graph showing the size of droplets ejected using the nozzle head of Example 1. [Figure 17] 10 is an optical microscope photograph of droplets ejected using a nozzle head of a comparative example. [Figure 18] 10 is a graph showing the size of droplets ejected using a nozzle head of a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] The droplet ejection device 100 includes a control unit 110 , a storage unit 115 , a power supply unit 120 , a drive unit 130 , a droplet ejection unit 140 , and a target object holder 160 .

[0032] The control unit 110 includes a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other arithmetic processing circuit. The control unit 110 controls the discharge process of the droplet discharge unit 140 using a preset droplet discharge program.

[0033] 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.

[0034] The power supply unit 120 is connected to the control unit 110, the drive unit 130, and the droplet ejection unit 140. The power supply unit 120 applies a voltage to the droplet ejection unit 140 based on a signal input from the control unit 110. In this example, the power supply unit 120 applies a pulsed voltage (1000 V in this example) to the droplet ejection unit 140. Note that the voltage is not limited to a pulsed voltage, and a constant voltage may be applied all the time. The voltage applied from the power supply unit 120 to the nozzle head 150 causes the liquid held in the ink tank 145 to be ejected as droplets from the tip 153 a (see FIG. 2(B)) of the droplet ejection nozzle 153 of the nozzle head 150, which will be described later, in the direction of the target object 200 (third direction D3).

[0035] The driving unit 130 is composed of driving members such as a motor, a belt, and gears. Based on instructions from the control unit 110, the driving unit 130 moves the droplet discharge unit 140 (more specifically, the nozzle head 150 described below) in one direction (in this example, the second direction D2) relative to the target object holder 160. Note that the driving unit 130 may move the target object while fixing the droplet discharge unit 140. The driving unit 130 may also be used in combination with a goniostage to finely adjust the position of the nozzle head 150.

[0036] The droplet ejection unit 140 includes an ink tank 145 and a nozzle head 150. An electrostatic ejection type inkjet nozzle is used for the nozzle head 150. Details of the nozzle head 150 will be described later. The nozzle head 150 is used by being fixed to a mount and an attachment (not shown). The mount and attachment may have a groove (long hole) in a portion corresponding to the droplet ejection nozzle 153 for temporarily storing ink supplied from the ink tank 145.

[0037] 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 limitations 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, this is not limiting, and the object holder 160 may hold the object 200 using a fixture.

[0038] (1-2. Configuration of the nozzle head 150) The configuration of the nozzle head 150 will be described in detail below. Fig. 2(A) is a plan view of the nozzle head 150. Fig. 2(B) is a cross-sectional view of the nozzle head 150 taken along line C1-C2. Fig. 3 is an enlarged view of the plan view of the nozzle head 150. Fig. 4 is a perspective view of the droplet discharge nozzle 153. Fig. 5(A) is a top view of the droplet discharge nozzle 153. Fig. 5(B) is a cross-sectional view of the droplet discharge nozzle 153 taken along line A1-A2. Fig. 6 is a perspective view of the pseudo-nozzle 155. Fig. 7(A) is a top view of the pseudo-nozzle 155. Fig. 7(B) is a cross-sectional view of the pseudo-nozzle 155 taken along line B1-B2.

[0039] As shown in FIGS. 2(A) and 2(B), the nozzle head 150 includes a plate portion 151, a droplet ejection nozzle portion 152, and a pseudo-nozzle portion 154.

[0040] The plate portion 151 is provided in a plate shape. The plate portion 151 extends in the first direction D1. The plate portion 151 is made of a metal material such as stainless steel. The thickness of the plate portion 151 is set appropriately. In this example, the thickness of the plate portion is not less than 10 μm and not more than 100 μm.

[0041] As shown in FIGS. 4, 5(A), and 5(B), the droplet discharge nozzle section 152 is provided on one surface of the plate section 151. The droplet discharge nozzle section 152 includes a plurality of droplet discharge nozzles 153. The droplet discharge nozzles 153 are arranged side by side in the first direction D1. In this embodiment, droplet discharge nozzles 153-1, 153-2, . . . , 153-(N-1), and 153-N are provided on the plate section 151. N is a natural number equal to or greater than 20. In this example, N=21. Note that when it is not necessary to separately describe the droplet discharge nozzles 153-1, 153-2, . . . , 153-(N-1), and 153-N, they will be described as droplet discharge nozzles 153. A metal material such as nickel is used for the droplet discharge nozzles 153. The droplet discharge nozzles 153 have a tapered shape.

[0042] The plate portion 151 has a through-hole 151o in a portion corresponding to (overlapping with) the droplet discharge nozzle 153, the through-hole 151o having an inner diameter r151o larger than the inner diameter r153a of the discharge port of the droplet discharge nozzle 153 (the opening 153ao of the tip portion 153a of the droplet discharge nozzle 153). The inner diameter of the through-hole of the plate portion 151 may be 1 μm or more and 100 μm or less. The inner diameter of the tip portion 153a of the droplet discharge 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 droplet discharge nozzle 153, a voltage may be applied to the plate portion 151 (or the ink tank 145), or a voltage may be applied to the ink. When a voltage is applied to the plate portion 151 and the droplet discharge nozzle 153, electrodes may be provided. The electrodes 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 a voltage is applied uniformly to the entire plate portion 151. Furthermore, although the present embodiment shows an example in which a voltage is applied to the droplet ejection nozzle 153, the plate portion 151, or the ink, a voltage may also be applied to a jig (for example, a mount or attachment) that holds the nozzle head 150.

[0043] As shown in FIG. 2, the pseudo-nozzle portion 154 is provided on the same surface of the plate portion 151 as the droplet discharge nozzle portion 152. The pseudo-nozzle portion 154 includes a plurality of pseudo-nozzles 155. The pseudo-nozzle portion 154 is provided around the droplet discharge nozzle portion 152. In this example, the pseudo-nozzle portions 154 are provided on both sides of the droplet discharge nozzle portion 152 in the first direction D1. The plurality of pseudo-nozzles 155 may be arranged in a predetermined area from the outermost pseudo-nozzle 155 (pseudo-nozzle 155-1). From the viewpoint of the electric field strength in the peripheral area, the plurality of pseudo-nozzles 155 may be provided over an entire range of 1 mm to 5 mm (preferably 2 mm) from the outermost pseudo-nozzle 155 in the first direction D1. In this case, the number of pseudo-nozzles 155 provided on one side of the droplet discharge nozzle portion 152 in the first direction D1 may be 1 / 5 or more of the number of droplet discharge nozzles 153. For example, the number of pseudo-nozzles 155 provided on one side of the droplet discharge nozzle section 152 in the first direction D1 may be 5 to 50, preferably 10 to 30. In this embodiment, a left pseudo-nozzle 155L including five pseudo-nozzles 155 (pseudo-nozzles 155-L1 to 155-L5) is provided on the left side of the droplet discharge nozzle section 152 including 21 droplet discharge nozzles 153. Similarly, a right pseudo-nozzle 155R including five pseudo-nozzles 155 (pseudo-nozzles 155-R1 to 155-R5) is provided on the right side of the droplet discharge nozzle section 152. Note that when it is not necessary to separately describe the pseudo-nozzles as 155-L1 to 155-L5, they will be described as pseudo-nozzles 155.

[0044] 3, the distance D1 between adjacent droplet discharge nozzles (the distance between droplet discharge nozzle 153-1 and droplet discharge nozzle 153-2), the distance D2 between adjacent droplet discharge nozzles 153 and pseudo-nozzles 155 (the distance between droplet discharge nozzle 153-1 and pseudo-nozzle 155-L5), and the distance D3 between adjacent pseudo-nozzles 155 (the distance between pseudo-nozzle 155-L4 and pseudo-nozzle 155-L5) are all the same. In this example, the distances D1, D2, and D3 between the nozzles are 200 μm.

[0045] As shown in FIGS. 6 and 7(B), the tip 155a of the pseudo-nozzle 155 does not have an opening and is closed. Therefore, the pseudo-nozzle 155 does not eject droplets. The pseudo-nozzle 155 is made of the same material as the droplet ejection nozzle 153. The pseudo-nozzle 155 may have the same shape as the droplet ejection nozzle 153. In this case, the height H155 of the pseudo-nozzle 155 (also referred to as the first height; specifically, the height from the upper surface 151a of the plate portion 151 to the tip 155a of the pseudo-nozzle 155) may be the same as the height H153 of the droplet ejection nozzle 153 (also referred to as the second height; specifically, the height from the upper surface 151a of the plate portion 151 to the tip 153a of the droplet ejection nozzle 153).

[0046] Here, when droplets are discharged by an electrostatic discharge method using a nozzle head including multiple nozzles, the electric field may be stronger in the peripheral region of the plate than in the center of the plate. In the case of the nozzle head 150 of this embodiment, pseudo-nozzle sections 154 are arranged around the droplet discharge nozzle section 152. In other words, multiple pseudo-nozzles 155 are arranged in the region where the electric field is stronger. Since the tips of the multiple pseudo-nozzles 155 are closed, droplets are not discharged. On the other hand, the electric field in the region where the droplet discharge nozzles 153 are arranged is uniform. This makes it possible to uniform the size of the droplets discharged from each droplet discharge nozzle 153.

[0047] (1-3. Manufacturing Method of Nozzle Head 150) The manufacturing method of the nozzle head 150 will be described with reference to the drawings. Figures 8(A) to 8(D) and 9(A) to 9(C) are cross-sectional views showing the manufacturing flow of the nozzle head.

[0048] First, as shown in FIG. 8(B), a matrix 2000 for forming the droplet discharge nozzles 153 and pseudo-nozzles 155 is prepared. In this embodiment, the concave matrix 2000 has a first surface 2000A and a second surface 2000B opposite the first surface 2000A. The matrix 2000 includes a first matrix 2001 and a second matrix 2005. Also provided on the first surface 2000A side are a first recess group 2006 having a plurality of first recesses 2007 for forming the droplet discharge nozzles, and a second recess group 2008 having a plurality of second recesses 2009 provided around the first recess group 2006 for forming the pseudo-nozzles.

[0049] The master die 2000 is formed by film formation, photolithography, and etching. Specifically, a plate-shaped first master die 2001 is prepared. The first master die 2001 may be a metal substrate, or an insulating substrate or a semiconductor substrate with a conductive film formed on its upper surface. As shown in FIG. 8(A), an insulating layer 2003 is formed on the upper surface of the first master die 2001 in a portion where the droplet discharge nozzles 153 are to be formed. Next, as shown in FIG. 8(B), a second master die 2005 made of a metal material is formed on the first master die 2001. The second master die 2005 may be formed by forming a metal layer and then processing it using photolithography, etching, or the like. At this time, the first master die 2001 is exposed at the bottom of the first recess 2007. The insulating layer 2003 is exposed at the bottom of the second recess 2009.

[0050] In the above, an example has been shown in which the insulating layer 2003 is formed in the portion where the droplet discharge nozzle 153 is formed, but the present invention is not limited to this. For example, the insulating layer 2003 may be formed on the entire upper surface of the first master mold 2001. In this case, a conductive layer or a catalyst layer may be formed in the portion where the insulating layer 2003 is exposed in the region where the pseudo-nozzle 155 is formed. Furthermore, the second master mold 2005 may be bonded to the first master mold 2001.

[0051] 8(C), a plurality of structures 1531 (also referred to as first structures) are formed in the first recess 2007 by electrolytic casting (plating), a plurality of structures 1551 (also referred to as second structures) are formed in the second recess 2009, and planar structures 1511 (also referred to as third structures) are formed on the first surface 2000A. The structures 1531, 1551, and 1511 are formed at the same time. The structures 1551 are formed around the structures 1531. In this example, the structures 1551 are formed on both sides of the group of structures 1531.

[0052] At this time, as shown in FIG. 8(B), the insulating layer 2003 is exposed at the bottom 2007B of the first recess 2007. Therefore, the presence of the insulating layer 2003 prevents electrolytic casting from being performed at the tip of the structure 1531. Therefore, the tip 1531a of the structure 1531 is opened. This results in the formation of a droplet discharge nozzle 153 having an opening 153ao at the tip 153a. On the other hand, the top surface of the first mother die 2001 is exposed at the tip of the structure 1551 (where the catalyst layer or conductive film is present), and therefore electrolytic casting is performed. Therefore, the tip of the structure 1551 is blocked. This results in the formation of a pseudo-nozzle 155.

[0053] Next, as shown in Fig. 8(D), a resist mask 2011 is formed on portions corresponding to the tip 153a of the droplet discharge nozzle 153 and the tip 155a of the pseudo-nozzle 155. Next, as shown in Fig. 9(A), a structure 1513 is formed by electrolytic casting on the exposed portion of the structure 1511. After the structure 1513 is formed, the resist mask 2011 is removed (Fig. 9(B)).

[0054] 9(C), the structures 1511, 1511, 1531, and 1551 are removed (released) from the matrix 2000. As a result, the plate portion 151 is formed from the structures 1511 and 1513. The droplet discharge nozzle 153 is formed from the structure 1531. The pseudo-nozzle 155 is formed from the structure 1551. In this way, the nozzle head 150 can be manufactured.

[0055] In the above, when a structure is formed on the matrix 2000 using electrolytic casting, the electric field tends to become non-uniform in the edge regions of the matrix 2000. However, in the present embodiment, the edge regions of the matrix 2000 are regions where pseudo-nozzles are formed. Therefore, the electric field in the region where the droplet discharge nozzles 153 are formed becomes uniform. This makes it possible to make the shape of the droplet discharge nozzles 153, and further the opening shape of the tip portions 153a, uniform.

[0056] Therefore, by using this embodiment, the shapes of the droplet ejection nozzles become uniform, and therefore the ejection uniformity of the droplet ejection nozzles can be improved.

[0057] Second Embodiment In this embodiment, a nozzle head 150A different from that in the first embodiment will be described. Specifically, an example in which a pseudo-nozzle portion is provided so as to surround a droplet ejection nozzle will be described. For convenience of explanation, some components will be omitted.

[0058] (2-1. Configuration of nozzle head 150A) Fig. 10(A) is a plan view of the nozzle head 150A. Fig. 10(B) is a cross-sectional view of the nozzle head 150A taken along line C1-C2. As shown in Fig. 10(A) and Fig. 10(B), the nozzle head 150A includes a plate portion 151, a droplet ejection nozzle portion 152A, and a pseudo-nozzle portion 154A.

[0059] The droplet discharge nozzle section 152A is provided on one surface of the plate section 151. The droplet discharge nozzle section 152A includes a plurality of droplet discharge nozzles 153A. The droplet discharge nozzles 153A are arranged side by side 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 droplet discharge nozzle section 152A includes 4 rows x 100 columns = 400 droplet discharge nozzles.

[0060] As shown in FIGS. 10A and 10B, the pseudo-nozzle portion 154A is provided on the same surface of the plate portion 151 as the droplet-discharging nozzle portion 152A. The pseudo-nozzle portion 154A includes a plurality of pseudo-nozzles 155A. The pseudo-nozzle portion 154A is provided around the droplet-discharging nozzle portion 152A. In this example, the pseudo-nozzle portion 154A is provided so as to surround the droplet-discharging nozzle portion 152A. The number of pseudo-nozzles provided in each row on both sides (left and right sides) in the first direction D1 and both sides (top and bottom sides) in the second direction D2 may be between two and thirty. Specifically, five rows of pseudo-nozzles 155A are provided on both the left and right sides of the droplet-discharging nozzle portion 152A. Furthermore, two rows of pseudo-nozzles 155A are provided on both the top and bottom sides of the droplet-discharging nozzle portion 152A. When the droplet discharge nozzle section 152A includes 1,000 rows x 1,000 columns = 1,000,000 droplet discharge nozzles, 20 rows (columns) of pseudo nozzles 155A may be provided on each of the top, bottom, left, and right sides. In this case, the pseudo nozzles 155A may be spaced 10 μm apart (pitch) from the outermost pseudo nozzle 155 (pseudo nozzle 155-1) to the adjacent pseudo nozzles 155A.

[0061] By using this embodiment, the shapes of the droplet ejection nozzles become uniform, and therefore the ejection uniformity of the droplet ejection nozzles can be improved.

[0062] <Third embodiment> In this embodiment, a nozzle head different from those in the first and second embodiments will be described. Specifically, an example in which pseudo nozzles are provided in a frame shape will be described. Note that portions that overlap with the first and second embodiments will be omitted as appropriate.

[0063] (3-1. Configuration of nozzle head 150B) Fig. 11(A) is a plan view of the nozzle head 150B. Fig. 11(B) is a schematic cross-sectional view of the nozzle head 150B between C1 and C2. As shown in Fig. 11(A) and Fig. 11(B), the nozzle head 150B includes a plate portion 151, a droplet ejection nozzle portion 152B, and a pseudo-nozzle portion 154B.

[0064] The droplet discharge nozzle section 152B is provided on one surface of the plate section 151. The droplet discharge nozzle section 152B includes a plurality of droplet discharge nozzles 153B. The droplet discharge nozzles 153B are arranged side by side in a first direction D1 and a second direction D2 that intersects with the first direction D1. In this example, the droplet discharge nozzle section 152B includes 4 rows x 100 columns = 400 droplet discharge nozzles.

[0065] As shown in FIGS. 11(A) and 11(B), the pseudo-nozzle portion 154B is provided on the same surface of the plate portion 151 as the droplet-discharging nozzle portion 152B. The pseudo-nozzle portion 154B includes a plurality of pseudo-nozzles 155B. The pseudo-nozzle portion 154B is provided around the droplet-discharging nozzle portion 152B. In this example, the pseudo-nozzle portion 154B is provided so as to surround the droplet-discharging nozzle portion 152B. Specifically, four frame-shaped pseudo-nozzles 155B are provided surrounding the droplet-discharging nozzle portion 152B. In this case, the pseudo-nozzles 155B may be rectangular, as shown in FIG. 11(B), or may be tapered toward their tips.

[0066] By using this embodiment, the shapes of the droplet ejection nozzles become uniform, and therefore the ejection uniformity of the droplet ejection nozzles can be improved.

[0067] <Fourth embodiment> In the first embodiment of the present invention, an example was shown in which the height H155 of the pseudo-nozzle 155 was the same as the height H153 of the droplet ejection nozzle 153, but the present invention is not limited to this. In this embodiment, a nozzle head different from that of the first embodiment will be described. Specifically, an example in which the height of the droplet ejection nozzle and the height of the pseudo-nozzle are different will be described. Note that portions that overlap with the first and second embodiments will be omitted as appropriate.

[0068] 12(A) is a top view of the pseudo-nozzle 155C. FIG. 12(B) is a cross-sectional view of the pseudo-nozzle 155C taken along the line B1-B2. The height H155C of the pseudo-nozzle 155C may be lower than the height H153 of the droplet ejection nozzle 153. This prevents the droplet ejection nozzle 153 from getting in the way when ejecting droplets. Therefore, by using one embodiment of the present invention, droplets can be ejected stably.

[0069] Fifth Embodiment In this embodiment, a nozzle head different from that of the first embodiment will be described. Specifically, an example in which a filler is filled into a pseudo-nozzle will be described. Note that parts that overlap with the first and second embodiments will be omitted as appropriate.

[0070] FIG. 13A is a top view of the pseudo nozzle 155D. FIG. 13B is a cross-sectional view of the pseudo nozzle 155D taken along the line B1-B2. The pseudo nozzle 155D may be filled with a filler 157. The filler 157 may be provided only at the tip of the pseudo nozzle 155, or may extend up to the plate portion 151. In this case, the pseudo nozzle 155D may be filled with a material other than the ink material. In this example, the pseudo nozzle 155 is filled with a resin material. The filler 157 may be made of a glass material or a ceramic material in addition to a resin material. Depending on the material used, the electric field may change. Therefore, from the perspective of uniforming the electric field, the filler may be made of a metal material or a conductive material. Furthermore, the filler 157 may be made of a liquid that does not exert an ejection force due to an electric field, such as a nonpolar solvent, silicone, a hydrocarbon solvent, or an ionic liquid. By using this embodiment, droplets can be ejected stably. [Example]

[0071] An example of a nozzle head according to one embodiment of the present invention will be described below.

[0072] <1. Nozzle head configuration> A nozzle head having a pseudo nozzle according to one embodiment of the present invention and a nozzle head not having a pseudo nozzle as a comparative example will be described below.

[0073] (Nozzle head of Example 1) The nozzle head of the first embodiment has the following configuration. Droplet ejection nozzles: 21 nozzles x 1 row Dummy nozzles: 5 on both sides of the droplet ejection nozzle The nozzle head of Example 1 was formed by electrolytic casting and bonded to a mount.

[0074] Fig. 14 is an electron microscope photograph of the droplet discharge nozzle. As shown in Fig. 14, the droplet discharge nozzles are arranged in a row. The droplet discharge nozzle has the following configuration. Distance between adjacent droplet ejection nozzles: 200 μm Droplet ejection nozzle height: 50 μm Inner diameter of the tip of the droplet ejection nozzle: 20 μm Tilt from the bottom to the tip of the droplet ejection nozzle: 20°

[0075] (Nozzle head of comparative example) The nozzle head in the comparative example has the following configuration. Droplet ejection nozzles: 100 nozzles x 1 row False nozzle: None The nozzle head of the comparative example was formed by electrolytic casting.

[0076] <2. Droplet ejection results> Fig. 15 is an optical microscope photograph of droplets ejected using the nozzle head of Example 1. Fig. 16 is a graph showing the size (diameter) of droplets ejected using the nozzle head of Example 1. Fig. 17 is an optical microscope photograph of droplets ejected using the nozzle head of the comparative example. Fig. 18 is a graph showing the size (diameter) of droplets ejected using the nozzle head of the comparative example.

[0077] 17 and 18, when the nozzle head of the comparative example was used, the droplet ejected from the first droplet ejection nozzle was 43% larger than the droplet ejected from the fifth droplet ejection nozzle, and the droplet ejected from the 100th droplet ejection nozzle was 39% larger than the droplet ejected from the 96th droplet ejection nozzle.

[0078] 15 and 16, when the nozzle head of Example 1 was used, the droplets ejected from the first droplet ejection nozzle were 13% larger than the droplets ejected from the fourth droplet ejection nozzle, and the droplets ejected from the 21st droplet ejection nozzle were 7% larger than the droplets ejected from the 17th droplet ejection nozzle.

[0079] Therefore, it was confirmed that by using the nozzle head of Example 1 according to one embodiment of the present invention, the size of the ejected droplets can be made more uniform than with the nozzle head of the comparative example.

[0080] (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.

[0081] In the first embodiment of the present invention, an example has been shown in which the pseudo-nozzle 155 has the same shape as the droplet ejection nozzle 153, but the present invention is not limited to this. The pseudo-nozzle 155 may have a shape different from that of the droplet ejection nozzle 153. For example, it may have a rectangular shape, a conical shape, or a semicircular shape. In other words, it is sufficient that the pseudo-nozzle 155 has a shape that protrudes from the plate portion 151.

[0082] In the first embodiment of the present invention, an example was shown in which the distance D1 between adjacent droplet ejection nozzles, the distance D2 between adjacent droplet ejection nozzles 153 and pseudo-nozzles 155, and the distance D3 between adjacent pseudo-nozzles 155 were all the same, but the present invention is not limited to this. The distance D1 between adjacent droplet ejection nozzles, the distance D2 between adjacent droplet ejection nozzles 153 and pseudo-nozzles 155, and the distance D3 between adjacent pseudo-nozzles 155 may all be different. For example, the distance D3 between adjacent pseudo-nozzles 155 may be smaller than the distance D1 between adjacent droplet ejection nozzles and the distance D2 between adjacent droplet ejection nozzles 153 and pseudo-nozzles 155. This can improve the uniformity of the electric field. [Explanation of symbols]

[0083] 100 droplet ejection device, 110 control unit, 115 memory unit, 120 power supply unit, 130 drive unit, 140 droplet ejection unit, 145 ink tank, 150 nozzle head, 151 plate unit, 151a upper surface, 151o through-hole, 152 droplet ejection nozzle unit, 153 droplet ejection nozzle, 153a tip unit, 153ao opening unit, 154 pseudo-nozzle unit, 155 pseudo-nozzle, 155a Tip portion, 157, filling material, 160, object holder, 200, object, 1511, structure, 1531, structure, 1531a, tip portion, 1533, structure, 1551, structure, 2000, master mold, 2001, first master mold, 2003, insulating layer, 2005, second master mold, 2006, first recess group, 2007, first recess, 2008, second recess group, 2009, second recess, 2011, resist mask

Claims

1. a plate portion having a through hole; a droplet discharge nozzle unit including a plurality of droplet discharge nozzles that are provided corresponding to the through holes of the plate unit and discharge droplets by an electrostatic discharge method; a pseudo-nozzle portion provided in the plate portion around the droplet ejection nozzle portion, the pseudo-nozzle portion including a plurality of pseudo-nozzles whose tips are closed, the droplet ejection nozzle and the pseudo-nozzle are provided to protrude from the plate portion, The inner diameter of the tip of the droplet discharge nozzle is 50 μm or less. Inkjet nozzle head.

2. the plurality of droplet ejection nozzles are arranged in a first direction, the pseudo-nozzle portions are provided on both sides of the droplet ejection nozzle portion in the first direction, The inkjet nozzle head according to claim 1 .

3. the plurality of pseudo-nozzles are provided over an entire range of 1 mm to 5 mm in the first direction from the outermost pseudo-nozzle; The inkjet nozzle head according to claim 2 .

4. the pseudo-nozzle unit includes five or more pseudo-nozzles on both sides of the droplet ejection nozzle unit in the first direction; The inkjet nozzle head according to claim 2 .

5. a first distance between adjacent droplet ejection nozzles is the same as a second distance between adjacent pseudo-nozzles; The inkjet nozzle head according to claim 1 .

6. the plurality of droplet discharge nozzles are arranged in a first direction and a second direction intersecting the first direction, The inkjet nozzle head according to claim 1 , wherein the pseudo-nozzle portion is provided so as to surround the droplet-discharging nozzle portion.

7. the pseudo-nozzles are arranged side by side on both sides in the first direction and on both sides in the second direction so as to correspond to the outermost droplet ejection nozzles of the plurality of droplet ejection nozzles, the number of the pseudo nozzles in each row provided on one side in the first direction and on one side in the second direction is 2 or more and 30 or less; The inkjet nozzle head according to claim 6.

8. The inkjet nozzle head according to claim 6 , wherein the pseudo nozzle has a frame shape.

9. a first height from the plate portion to the tip of the pseudo-nozzle is lower than a second height from the plate portion to the tip of the droplet ejection nozzle; The inkjet nozzle head according to any one of claims 1 to 8.

10. A droplet ejection device comprising the inkjet nozzle head according to claim 1 .

11. preparing a matrix having a first surface and a second surface opposite to the first surface, the matrix including a first recess group having a plurality of first recesses on the first surface side, and a second recess group having a plurality of second recesses provided around the first recess group; forming a plurality of first structures having open ends in the first recess, forming a plurality of second structures having closed ends in the second recess, and forming a planar third structure on the first surface; forming a resist mask so as to shield the plurality of first structures and the plurality of second structures; forming a fourth structure on the third structure; removing the resist mask and releasing the first structure, the second structure, the third structure, and the fourth structure from the matrix, thereby forming a droplet ejection nozzle from the first structure, forming a pseudo-nozzle from the second structure, and forming a plate portion from the third structure and the fourth structure; A method for manufacturing a nozzle head.

12. The method for manufacturing a nozzle head according to claim 11 , wherein the insulating layer is exposed at the bottom of the first recess.

13. the plurality of droplet ejection nozzles are aligned in a first direction, the plurality of pseudo-nozzles are formed on both sides of the droplet ejection nozzle in the first direction; The method for manufacturing a nozzle head according to claim 12.

14. the plurality of pseudo-nozzles are formed over an entire range of 1 mm to 5 mm in the first direction from the pseudo-nozzle arranged on the outermost side; The method for manufacturing a nozzle head according to claim 13.

15. The method for manufacturing a nozzle head according to claim 13 , wherein five or more pseudo nozzles are formed on both sides of the droplet ejection nozzle.

16. a first distance between adjacent droplet ejection nozzles is the same as a second distance between adjacent pseudo-nozzles; The method for manufacturing the nozzle head according to any one of claims 12 to 15.

17. the plurality of droplet ejection nozzles are formed side by side in a first direction and a second direction intersecting the first direction, the pseudo-nozzle is formed so as to surround the droplet ejection nozzle; The method for manufacturing a nozzle head according to claim 12.

18. the pseudo-nozzles are formed side by side on both sides in the first direction and on both sides in the second direction so as to correspond to the outermost droplet ejection nozzles of the plurality of droplet ejection nozzles, the number of the pseudo nozzles in each row formed on one side in the first direction and one side in the second direction is 2 or more and 30 or less; The method for manufacturing a nozzle head according to claim 17.

19. The pseudo nozzle is formed to have a frame shape. The method for manufacturing a nozzle head according to claim 17.

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