Nozzle, nozzle manufacturing method and droplet discharge device

Abstract

The nozzle includes: a plate portion configured as a plate; a droplet discharge nozzle portion disposed on the plate portion and including a plurality of droplet discharge nozzles that discharge droplets by electrostatic discharge; and a dummy nozzle portion disposed on the plate portion and surrounding the droplet discharge nozzle portion and including a plurality of dummy nozzles. In the above nozzle, the plurality of droplet discharge nozzles are arranged side by side along a first direction, and the dummy nozzle portions may also be disposed on both sides of the droplet discharge nozzle portions.

Description

[Technical Field]

[0001] This invention relates to a nozzle, a method for manufacturing the nozzle, and a droplet discharge device. [Previous Technology]

[0002] In recent years, inkjet printing technology has been applied in industrial processes. For example, the manufacturing process of color filters for liquid crystal displays is one such example. As an inkjet printing technology, piezoelectric printheads, which eject droplets through mechanical pressure or vibration, have been the most common method used in the past. However, electrostatic ejection printheads, which can eject finer droplets, have attracted attention. Patent Document 1 discloses an electrostatic ejection inkjet recording device.

[0003] 『Patent Document』《Patent Document 1》: Japanese Patent Publication No. H10-34967 [Summary of the Invention]

[0004] Recently, in the application of electrostatic ejection inkjet heads, multi-nozzle technology has been developed from the perspective of improving productivity. However, in the case of multiple nozzles, there is a risk that the nozzle diameters will become uneven. When the nozzle diameters are uneven, it is impossible to uniformly eject droplets from the target object. As a result, it is difficult to form a uniform image.

[0005] Therefore, one of the objects of the present invention is to provide a multi-nozzle system with high discharge uniformity and a droplet discharge device having the multi-nozzle system.

[0006] According to one embodiment of the present invention, a nozzle is provided, comprising: a plate portion having a through hole, a droplet discharge nozzle portion having a plurality of droplet discharge nozzles disposed corresponding to the through hole of the plate portion and having a plurality of droplet discharge nozzles for discharging droplets by electrostatic discharge, and a pseudo-nozzle portion having a plurality of pseudo-nozzles disposed around the periphery of the droplet discharge nozzle portion in the plate portion and having a front end closed.

[0007] In the above-mentioned nozzle, the aforementioned plurality of droplet discharge nozzles may also be arranged in parallel along the first direction, and the aforementioned pseudo-nozzle portion may also be arranged on both sides of the aforementioned droplet discharge nozzle portion in the aforementioned first direction.

[0008] In the above-mentioned nozzle, the aforementioned plurality of dummy nozzles may also be provided as a whole, extending from the outermost dummy nozzle toward the aforementioned first direction over a range of 1 mm or more and 5 mm or less.

[0009] In the above-mentioned nozzle, the aforementioned pseudo-nozzle section may also include more than 5 pseudo-nozzles on both sides of the aforementioned droplet discharge nozzle section in the first direction.

[0010] In the above-mentioned nozzle, the first distance between adjacent droplet discharge nozzles can also be the same as the second distance between adjacent pseudo-nozzles.

[0011] In the above-mentioned nozzle, the aforementioned plurality of droplet discharge nozzles may also be arranged in parallel along the first direction and the second direction intersecting the first direction, and the aforementioned pseudo-nozzle portion may also be arranged in a manner that surrounds the aforementioned droplet discharge nozzle portion.

[0012] In the above-mentioned nozzle, the aforementioned dummy nozzles may also be arranged side by side on both sides of the aforementioned first direction and both sides of the aforementioned second direction in a manner corresponding to each of the aforementioned multiple droplet discharge nozzles arranged on the outside. The number of the aforementioned dummy nozzles arranged on one side of the aforementioned first direction and one side of the aforementioned second direction may be more than 2 and less than 30.

[0013] In the above-mentioned nozzle, the aforementioned dummy nozzle may also have a frame shape.

[0014] In the above-mentioned nozzle, the first height from the plate portion to the front end of the dummy nozzle may also be lower than the second height from the plate portion to the front end of the droplet discharge nozzle.

[0015] According to one embodiment of the present invention, a droplet discharge device comprising the above-described nozzle is provided.

[0016] According to one embodiment of the present invention, a method for manufacturing a nozzle is provided, wherein a first recess group having a first surface and a second surface opposite to the first surface and including a plurality of first recesses on the side of the first surface, and a second recess group having a plurality of second recesses disposed around the first recess group, a parent mold is prepared, a plurality of first structures with open front ends are formed in the first recesses, a plurality of second structures with closed front ends are formed in the second recesses, and a plurality of second structures with closed front ends are formed in the first recesses. A planar third structure is formed in the surface, and a photoresist mask is formed in such a way as to cover the aforementioned plurality of first structures and the aforementioned plurality of second structures. A fourth structure is formed on the aforementioned third structure. The aforementioned photoresist mask is removed, and the aforementioned first structure, the aforementioned second structure, the aforementioned third structure and the aforementioned fourth structure are demolded from the aforementioned parent mold. A droplet discharge nozzle is formed from the aforementioned first structure, a pseudo nozzle is formed from the aforementioned second structure, and a plate portion is formed from the aforementioned third structure and the aforementioned fourth structure.

[0017] In the above-mentioned nozzle, the insulating layer may also be exposed at the bottom of the aforementioned first recess.

[0018] In the above-mentioned nozzle, the aforementioned plurality of droplet discharge nozzles may also be formed in parallel along the first direction, and the aforementioned plurality of dummy nozzles may also be formed on both sides of the aforementioned droplet discharge nozzles in the aforementioned first direction.

[0019] In the above-mentioned nozzle, the aforementioned plurality of dummy nozzles may also be formed as a whole from the outermost dummy nozzle, which extends over a range of 1 mm or more and 5 mm or less in the first direction.

[0020] In the above-mentioned nozzle, the aforementioned pseudo-nozzles may also be formed in more than 5 forms on both sides of the aforementioned droplet discharge nozzle.

[0021] In the above-mentioned nozzle, the first distance between adjacent droplet discharge nozzles can also be the same as the second distance between adjacent pseudo-nozzles.

[0022] In the above-mentioned nozzle, the aforementioned plurality of droplet discharge nozzles may also be formed in parallel along the first direction and the second direction intersecting the first direction, and the aforementioned pseudo-nozzle may also be formed in a manner that surrounds the aforementioned droplet discharge nozzle.

[0023] In the above-mentioned nozzle, the aforementioned dummy nozzles may also be formed in parallel on both sides of the aforementioned first direction and both sides of the aforementioned second direction in a manner corresponding to each of the aforementioned multiple droplet discharge nozzles formed on the outer side. The number of the aforementioned dummy nozzles in each row formed on one side of the aforementioned first direction and one side of the aforementioned second direction may be more than 2 and less than 30.

[0024] In the above-mentioned nozzle, the aforementioned dummy nozzle can also be formed in a frame shape.

[0025] By using one embodiment of the present invention, a multi-nozzle system with high discharge uniformity and a droplet discharge device having the multi-nozzle system can be provided.

Implementation Method

[0044] The various embodiments of the invention disclosed in this application will be described below with reference to the drawings. However, the invention may be implemented in various forms without departing from its spirit and is not to be interpreted as limited to the description of the embodiments exemplified below.

[0045] Furthermore, in the drawings referenced in this embodiment, the same or similar symbols are used to mark the same parts or parts with the same function (only symbols such as A, B, or -1, -2, etc. are marked after the numbers), and repeated descriptions are sometimes omitted. Also, the dimensional ratios in the drawings may sometimes differ from the actual ratios or omit a part of the structure from the drawings for ease of explanation.

[0046] Furthermore, in the detailed description of the present invention, when specifying the positional relationship between a structure and other structures, the terms "above" and "below" do not only include the case of being directly above or below a structure, unless otherwise noted, they are considered to include the case where there are other structures in between.

[0047] <First Implementation Type>

[0048] (1-1. Structure of the droplet discharge device 100)

[0049] Figure 1 is a schematic diagram of a droplet discharge device 100 related to one embodiment of the present invention.

[0050] The droplet discharge device 100 includes a control unit 110, a storage unit 115, a power supply unit 120, a drive unit 130, a droplet discharge unit 140, and a target support unit 160.

[0051] 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 circuits. The control unit 110 uses a pre-set droplet discharge program to control the discharge process of the droplet discharge unit 140.

[0052] The storage unit 115 has the function of storing a database for the "droplet discharge program" and "various information used by the droplet discharge program". The storage unit 115 uses memory, solid-state drive (SSD) or other storage-enabled components.

[0053] The power supply unit 120 is connected to the control unit 110, the drive unit 130, and the droplet discharge unit 140. The power supply unit 120 applies voltage to the droplet discharge unit 140 based on the 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 discharge unit 140. In addition, a fixed voltage can be applied continuously without being limited to the pulsed voltage. Through the voltage applied to the printhead 150 by the power supply unit 120, the liquid loaded in the ink tank 145 is discharged from the printhead 150 as a droplet at the front end 153a (see Figure 2(B)) of the droplet discharge nozzle 153 described later, along the direction of the target object 200 (third direction D3).

[0054] The drive unit 130 is composed of drive components such as a motor, belt, and gears. Based on instructions from the control unit 110, the drive unit 130 moves the droplet discharge section 140 (more specifically, the nozzle 150 described later) relative to the target support section 160 in one direction (in this example, the second direction D2). Furthermore, the drive unit 130 can also fix the droplet discharge section 140 while moving the target object. Additionally, the drive unit 130 can be used in conjunction with a goniometer to fine-tune the position of the nozzle 150.

[0055] The droplet discharge section 140 includes an ink reservoir 145 and a printhead 150. The printhead 150 uses an electrostatic discharge type inkjet nozzle. Details of the printhead 150 will be described later. The printhead 150 can be fixed to a mount and an accessory (not shown) for use. The mount and accessory may also have grooves (elongated holes) in the portion corresponding to the droplet discharge nozzle 153 for temporarily storing ink supplied from the ink reservoir 145.

[0056] The target support portion 160 functions to support the target object 200. In this example, a platform is used for the target support portion 160. The mechanism by which the target support portion 160 supports the target object 200 is not particularly limited; a general support mechanism can be used. In this example, the target object 200 is vacuum-adsorbed onto the target support portion 160. Furthermore, the target support portion 160 is not limited to this; a fixture can also be used to support the target object 200.

[0057] (1-2. Construction of nozzle 150)

[0058] The structure of the nozzle 150 is described in detail below. Figure 2(A) is a plan view of the nozzle 150. Figure 2(B) is a cross-sectional view of the nozzle 150 between C1 and C2. Figure 3 is an enlarged plan view of the nozzle 150. Figure 4 is a perspective view of the droplet discharge nozzle 153. Figure 5(A) is a top view of the droplet discharge nozzle 153. Figure 5(B) is a cross-sectional view between A1 and A2 in the droplet discharge nozzle 153. Figure 6 is a perspective view of the dummy nozzle 155. Figure 7(A) is a top view of the dummy nozzle 155. Figure 7(B) is a cross-sectional view between B1 and B2 in the dummy nozzle 155.

[0059] As shown in Figures 2(A) and 2(B), the nozzle 150 includes a plate portion 151, a droplet discharge nozzle portion 152, and a pseudo-nozzle portion 154.

[0060] The plate portion 151 is provided in a plate shape. The plate portion 151 extends along the first direction D1. Metal materials such as stainless steel can be used for the plate portion 151. The thickness of the plate portion 151 can be appropriately set. In this example, the thickness of the plate portion is 10 μm or more and 100 μm or less.

[0061] As shown in Figures 4, 5(A), and 5(B), a droplet discharge nozzle portion 152 is provided on one side of the plate portion 151. The droplet discharge nozzle portion 152 includes a plurality of droplet discharge nozzles 153. The droplet discharge nozzles 153 are arranged side by side along 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 portion 151. N is a natural number of 20 or more. In this example, N = 21. Furthermore, unless it is necessary to separately describe the droplet discharge nozzles 153-1, 153-2, ..., 153-(N-1), and 153-N, the droplet discharge nozzle 153 will be described. The droplet discharge nozzle 153 can be made of a metal material such as nickel. The droplet discharge nozzle 153 has a tapered shape.

[0062] The plate portion 151 has a through hole 151o in the portion (overlapping portion) corresponding to the droplet discharge nozzle 153. The through hole 151o has an inner diameter r151o larger than the inner diameter r153a of the discharge port of the droplet discharge nozzle 153 (the opening portion 153ao of the front end portion 153a of the droplet discharge nozzle 153). The inner diameter of the through hole of the plate portion 151 can be 1 μm or more and 100 μm or less. The inner diameter of the front end portion 153a of the droplet discharge nozzle 153 can be several hundred nm 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, voltage can be applied to the droplet discharge nozzle 153, voltage can be applied to the plate portion 151 (or ink tank 145), and voltage can also be applied to the ink. Electrodes can also be provided when applying voltage to the plate portion 151 and the droplet discharge nozzle 153. The electrodes can be made of materials such as tungsten, nickel, molybdenum, titanium, gold, silver, copper, and platinum. In this case, multiple electrodes can be provided to uniformly apply voltage to the entire plate portion 151. Furthermore, although this embodiment discloses an example of applying voltage to the droplet discharge nozzle 153, the plate portion 151, or the ink, voltage can also be applied to the fixture (e.g., the holder and accessories) holding the printhead 150.

[0063] As shown in FIG. 2, a dummy nozzle portion 154 is disposed in the plate portion 151 on the same surface as the droplet discharge nozzle portion 152. The dummy nozzle portion 154 includes a plurality of dummy nozzles 155. The dummy nozzle portion 154 is disposed around the periphery of the droplet discharge nozzle portion 152. In this example, the dummy nozzle portion 154 is disposed on both sides of the droplet discharge nozzle portion 152 in the first direction D1. Furthermore, the plurality of dummy nozzles 155 can also be disposed in a designated area from the outermost dummy nozzle 155 (dummy nozzle 155-1). From the viewpoint of the electric field strength in the periphery, the plurality of dummy nozzles 155 can also be disposed as a whole in a range of 1 mm or more and 5 mm or less (preferably 2 mm) extending toward the first direction D1 from the outermost dummy nozzle 155. In this case, the number of dummy nozzles 155 disposed on one side of the droplet discharge nozzle portion 152 in the first direction D1 can also be 1 / 5 or more relative to the number of droplet discharge nozzles 153. For example, the number of dummy nozzles 155 provided on one side of the droplet discharge nozzle section 152 in the first direction D1 can be 5 or more and 50 or less, preferably 10 or more and 30 or less. In this embodiment, a left dummy nozzle 155L containing 5 dummy nozzles 155 (dummy nozzles 155-L1 to 155-L5) is provided on the left side of the droplet discharge nozzle section 152, which includes 21 droplet discharge nozzles 153. Similarly, a right dummy nozzle 155R containing 5 dummy nozzles 155 (dummy nozzles 155-R1 to 155-R5) is provided on the right side of the droplet discharge nozzle section 152. Furthermore, unless it is necessary to describe them separately as dummy nozzles 155-L1 to 155-L5, they will be described using the dummy nozzles 155 as an example.

[0064] As shown in Figure 3, the distances between adjacent droplet discharge nozzles (the distance between droplet discharge nozzle 153-1 and droplet discharge nozzle 153-2) d1, the distances between adjacent droplet discharge nozzle 153 and dummy nozzle 155 (the distance between droplet discharge nozzle 153-1 and dummy nozzle 155-L5) d2, and the distances between adjacent dummy nozzles 155 (the distance between dummy nozzle 155-L4 and dummy nozzle 155-L5) d3 are all the same. In this example, the distances d1, d2, and d3 between each nozzle are 200 μm.

[0065] As shown in Figures 6 and 7(B), the front end 155a of the dummy nozzle 155 is closed and does not have an opening. Therefore, the dummy nozzle 155 will not discharge droplets. The dummy nozzle 155 is made of the same material as the droplet discharge nozzle 153. The dummy nozzle 155 may also have the same shape as the droplet discharge nozzle 153. In this case, the height H155 of the dummy nozzle 155 (also referred to as the first height, specifically the height from the top surface 151a of the plate portion 151 to the front end 155a of the dummy nozzle 155) may also be the same as the height H153 of the droplet discharge nozzle 153 (also referred to as the second height, specifically the height from the top surface 151a of the plate portion 151 to the front end 153a of the droplet discharge nozzle 153).

[0066] Here, when using a nozzle containing multiple nozzles to discharge droplets via electrostatic discharge, the electric field may sometimes be larger in the peripheral region of the plate compared to the center. In the case of the nozzle 150 of this embodiment, a dummy nozzle section 154 is arranged around the droplet discharge nozzle section 152. In short, multiple dummy nozzles 155 are arranged in the region where the electric field is larger. Since the front ends of the multiple dummy nozzles 155 are closed, they do not discharge droplets. On the other hand, the electric field in the region where the droplet discharge nozzles 153 are arranged becomes uniform. This makes the size of the droplets discharged from each droplet discharge nozzle 153 uniform.

[0067] (1-3. Manufacturing method of nozzle 150)

[0068] The manufacturing method of the nozzle 150 is illustrated using diagrams. Figures 8 (A) to (D) and 9 (A) to (C) are cross-sectional views illustrating the manufacturing process of the nozzle.

[0069] First, as shown in FIG8(B), a master mold 2000 is prepared for forming the droplet discharge nozzle 153 and the dummy nozzle 155. In this embodiment, the concave master mold 2000 has a first surface 2000A and a second surface 2000B on the opposite side of the first surface 2000A. The master mold 2000 includes a first master mold 2001 and a second master mold 2005. Furthermore, a first recess group 2006 having a plurality of first recesses 2007 for forming the droplet discharge nozzle is provided on the first surface 2000A side, and a second recess group 2008 having a plurality of second recesses 2009 for forming the dummy nozzle is provided around the aforementioned first recess group 2006.

[0070] The master mold 2000 is formed by performing film deposition, photolithography, and etching. Specifically, a first master mold 2001 is prepared to be plate-shaped. The first master mold 2001 can be a metal substrate or a substrate on which a conductive film is formed. As shown in FIG8(A), an insulating layer 2003 is formed on the portion of the first master mold 2001 where the droplet discharge nozzle 153 is formed. Next, as shown in FIG8(B), a second master mold 2005 made of metal material is formed on the first master mold 2001. The second master mold 2005 can also be formed by forming a metal layer and then processing it by photolithography and etching. At this time, the insulating layer 2003 is exposed at the bottom of the first recess 2007. The first master mold 2001 is exposed at the bottom of the second recess 2009.

[0071] Furthermore, while the above describes an example of forming an insulating layer 2003 on the portion where the droplet discharge nozzle 153 is formed, the present invention is not limited thereto. For example, the insulating layer 2003 may also be formed entirely on the top surface of the first mother mold 2001. In this case, a conductive layer or a catalyst layer may also be formed on the exposed portion of the insulating layer 2003 in the region where the dummy nozzle 155 is formed. Furthermore, the second mother mold 2005 may also be bonded to the first mother mold 2001.

[0072] Next, as shown in FIG8(C), by electrolytic casting (electroplating), a plurality of structures 1531 (also referred to as the first structure) are formed in the first recess 2007, a plurality of structures 1551 (also referred to as the second structure) are formed in the second recess 2009, and a planar structure 1511 (also referred to as the third structure) is formed in the first surface 2000A. Structures 1531, 1551, and 1511 are formed at the same time. Structure 1551 is formed around the periphery of structure 1531. In this example, it is formed on both sides of the group of structures 1531.

[0073] At this time, as shown in FIG8(B), the insulating layer 2003 is exposed at the bottom 2007B of the first recess 2007. Therefore, the front end of the structure 1531 is not subjected to electrolytic casting due to the presence of the insulating layer 2003. Therefore, the front end 1531a of the structure 1531 is opened. Thereby, a droplet discharge nozzle 153 with an opening 153ao at the front end 153a can be formed. On the other hand, the front end of the structure 1551 is exposed on the top of the first parent mold 2001 (where a catalyst layer or conductive layer is present), and is therefore subjected to electrolytic casting. Therefore, the front end of the structure 1551 is closed. Accordingly, a pseudo nozzle 155 can be formed.

[0074] Next, as shown in FIG8(D), a photoresist mask 2011 is formed on the portion of the front end 153a of the corresponding droplet discharge nozzle 153 (specifically, the front end 1531a) and the portion of the front end 155a of the corresponding pseudo nozzle 155 (specifically, the front end 1551a). Next, as shown in FIG9(A), the exposed portion of the structure 1511 is formed into a structure 1513 by electrolytic casting. After the structure 1513 is formed, the photoresist mask 2011 is removed (FIG9(B)).

[0075] Finally, as shown in Figure 9(C), structures 1511, 1513, 1531, and 1551 are removed (demolded) from the parent mold 2000. Herein, plate portion 151 is formed from structures 1511 and 1513. Droplet discharge nozzle 153 is formed from structure 1531. Pseudo-nozzle 155 is formed from structure 1551. Through the above, nozzle 150 can be manufactured.

[0076] In the above description, when the structure is formed on the parent mold 2000 using electrolytic casting, the electric field in the edge region of the parent mold 2000 tends to become non-uniform. However, in this embodiment, the edge region of the parent mold 2000 is the region where the pseudo-nozzle is formed. Therefore, the electric field in the region where the droplet discharge nozzle 153 is formed becomes uniform. This makes the shape of the droplet discharge nozzle 153—more specifically, the opening shape of the front end 153a—uniform.

[0077] Therefore, by using this embodiment, the shapes of the multiple droplet discharge nozzles become uniform. Thus, the uniformity of discharge using multiple droplet discharge nozzles can be improved.

[0078] <Second Implementation Type>

[0079] In this embodiment, a nozzle 150A that differs from the first embodiment will be described. Specifically, an example in which the dummy nozzle portion is arranged to surround the droplet discharge nozzle will be described. Furthermore, for the sake of explanation, it is appropriate to omit certain components.

[0080] (2-1. Construction of Nozzle 150A)

[0081] Figure 10(A) is a plan view of nozzle 150A. Figure 10(B) is a cross-sectional view of nozzle 150A between C1 and C2. As shown in Figures 10(A) and 10(B), nozzle 150A includes plate portion 151, droplet discharge nozzle portion 152A and pseudo nozzle portion 154A.

[0082] A droplet discharge nozzle section 152A is provided on one side 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 along a first direction D1 and a second direction D2 that intersects (orthogonal in this example) the first direction D1. In this example, the droplet discharge nozzle section 152A includes 4 columns × 100 rows = 400 droplet discharge nozzles.

[0083] As shown in Figures 10(A) and 10(B), a dummy nozzle portion 154A is disposed on the same surface as the droplet discharge nozzle portion 152A within the plate portion 151. The dummy nozzle portion 154A includes a plurality of dummy nozzles 155A. The dummy nozzle portion 154A is disposed around the droplet discharge nozzle portion 152A. In this example, the dummy nozzle portion 154A is disposed in a manner that surrounds the droplet discharge nozzle portion 152A. The number of dummy nozzles disposed in each row on both sides (left and right sides) in the first direction D1 and on both sides (upper and lower sides) in the second direction D2 can be more than 2 and less than 30. Specifically, 5 rows of dummy nozzles 155A are disposed on the left and right sides of the droplet discharge nozzle portion 152A. Furthermore, 2 columns of dummy nozzles 155A are disposed on the upper and lower sides of the droplet discharge nozzle portion 152A. Furthermore, when the droplet discharge nozzle section 152A includes 1,000 columns × 1,000 rows = 1,000,000 droplet discharge nozzles, 20 columns (rows) of dummy nozzles 155A can also be arranged on each of the top, bottom, left, and right sides. In this case, the interval (spacing) between the multiple dummy nozzles 155A from the outermost dummy nozzle 155 (dummy nozzle 155-1) to the adjacent dummy nozzle 155A can also be 10 μm.

[0084] By using this embodiment, the shapes of the multiple droplet discharge nozzles become uniform. Therefore, the uniformity of discharge using multiple droplet discharge nozzles can be improved.

[0085] <Third Implementation Type>

[0086] In this embodiment, a nozzle that differs from the first and second embodiments will be described. Specifically, an example of a dummy nozzle being configured in a frame shape will be described. Furthermore, portions that overlap with the first and second embodiments will be omitted from the description.

[0087] (3-1. Construction of Nozzle 150B)

[0088] Figure 11(A) is a plan view of nozzle 150B. Figure 11(B) is a schematic cross-sectional view of nozzle 150B between C1 and C2. As shown in Figures 11(A) and 11(B), nozzle 150B includes plate portion 151, droplet discharge nozzle portion 152B and pseudo nozzle portion 154B.

[0089] A droplet discharge nozzle section 152B is disposed on one side 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 along a first direction D1 and a second direction D2 intersecting the first direction D1. In this example, the droplet discharge nozzle section 152B includes 4 columns × 100 rows = 400 droplet discharge nozzles.

[0090] As shown in Figures 11(A) and 11(B), a dummy nozzle portion 154B is disposed in the plate portion 151 on the same surface as the droplet discharge nozzle portion 152B. The dummy nozzle portion 154B includes a plurality of dummy nozzles 155B. The dummy nozzle portion 154B is disposed around the droplet discharge nozzle portion 152B. In this example, the dummy nozzle portion 154B is disposed in a manner that surrounds the droplet discharge nozzle portion 152B. Specifically, four frame-shaped dummy nozzles 155B are provided that surround the droplet discharge nozzle portion 152B. At this time, as shown in Figure 11(B), the dummy nozzles 155B may be rectangular or taper towards the front end.

[0091] By using this embodiment, the shapes of the multiple droplet discharge nozzles become uniform. Therefore, the uniformity of discharge using multiple droplet discharge nozzles can be improved.

[0092] <Fourth Implementation Type>

[0093] In the first embodiment of the present invention, an example was disclosed in which the height H155 of the dummy nozzle 155 was the same as the height H153 of the droplet discharge nozzle 153, but the present invention is not limited thereto. In this embodiment, a nozzle different from that in the first embodiment will be described. Specifically, an example in which the height of the droplet discharge nozzle is different from the height of the dummy nozzle will be described. Furthermore, portions that are repeated in the first and second embodiments will be omitted from the description as appropriate.

[0094] Figure 12(A) is a top view of the dummy nozzle 155C. Figure 12(B) is a cross-sectional view between B1 and B2 in the dummy nozzle 155C. The height H155C of the dummy nozzle 155C can also be lower than the height H153 of the droplet discharge nozzle 153. Therefore, it will not cause obstruction when the droplet is discharged from the droplet discharge nozzle 153. Thus, by using one embodiment of the present invention, droplet discharge can be stabilized.

[0095] <Fifth Implementation Type>

[0096] In this embodiment, a nozzle different from that in the first embodiment will be described. Specifically, an example in which a filler is filled in the dummy nozzle will be described. Furthermore, the parts that are repeated with the first and second embodiments will be omitted from the description.

[0097] Figure 13(A) is a top view of the dummy nozzle 155D. Figure 13(B) is a cross-sectional view between B1 and B2 in the dummy nozzle 155D. The dummy nozzle 155D can also be filled with filler 157. The filler 157 can be provided only at the front end of the dummy nozzle 155, or it can fill all the way to the plate portion 151. In this case, the dummy nozzle 155D can also be filled with a material different from the ink material. In this example, the dummy nozzle 155 is filled with resin material. In addition to resin material, glass material and ceramic material can also be used for filler 157. In addition, depending on the filling material, the electric field formed may sometimes change. Therefore, from the viewpoint of electric field homogenization, metal material or conductive material can also be used for filling. Furthermore, liquids that do not work by the discharge force of the electric field can also be used for filler 157, such as non-polar solvents, polysiloxanes, hydrocarbon solvents, and ionic liquids. By using this embodiment, droplets can be stably discharged.

[0098] 『Example』

[0099] The following describes an embodiment of the nozzle related to one type of the present invention.

[0100] 〈1. Sprinkler Nozzle Construction〉

[0101] The following describes a nozzle with a dummy nozzle and a nozzle without a dummy nozzle as a comparative example, using one embodiment of the present invention.

[0102] (Sprayer of Example 1)

[0103] The nozzle structure of Example 1 is as follows. Droplet discharge nozzle: 21 × 1 row of pseudo-nozzles: 5 on each side of the droplet discharge nozzle

[0104] The nozzle of Example 1 is formed by electrolytic casting and is attached to the base.

[0105] Figure 14 is an electron microscope image of the droplet discharge nozzles. As shown in Figure 14, the droplet discharge nozzles are arranged side by side in a row. The structure of the droplet discharge nozzles is as follows: Distance between adjacent droplet discharge nozzles: 200 μm; Height of droplet discharge nozzles: 50 μm; Inner diameter of the front end of the droplet discharge nozzle: 20 μm; Inclination from the bottom of the droplet discharge nozzle towards the front end: 20°

[0106] (Comparative example nozzle)

[0107] The nozzle in the comparative example is constructed as follows: Droplet discharge nozzles: 100 x 1 row; Pseudo-nozzles: None

[0108] The nozzle of the comparative example is formed by electrolytic casting.

[0109] 〈2. Droplet Ejection Results〉

[0110] Figure 15 is an optical microscope photograph of droplets ejected using the nozzle of Example 1. Figure 16 is a diagram showing the size (diameter) of droplets ejected using the nozzle of Example 1. Figure 17 is an optical microscope photograph of droplets ejected using the nozzle of the comparative example. Figure 18 is a diagram showing the size (diameter) of droplets ejected using the nozzle of the comparative example.

[0111] As shown in Figures 17 and 18, when using the nozzle of the comparative example, the droplets discharged from the first droplet discharge nozzle are 43% larger than the droplets discharged from the fifth droplet discharge nozzle. Furthermore, the droplets discharged from the 100th droplet discharge nozzle are 39% larger than the droplets discharged from the 96th droplet discharge nozzle.

[0112] On the other hand, as shown in Figures 15 and 16, when using the nozzle of Embodiment 1, the droplets discharged from the first droplet discharge nozzle are 13% larger than the droplets discharged from the fourth droplet discharge nozzle. Furthermore, the droplets discharged from the 21st droplet discharge nozzle are 7% larger than the droplets discharged from the 17th droplet discharge nozzle.

[0113] Therefore, it has been confirmed that by using the nozzle of Embodiment 1, which is related to one embodiment of the present invention, the size of the discharged droplets can be made more uniform compared to the nozzle of the comparative example.

[0114] (Modified Example)

[0115] Within the scope of the present invention, any modifications and alterations can be conceived by those skilled in the art, and such modifications and alterations are also understood to fall within the scope of the present invention. For example, for the aforementioned embodiments, those skilled in the art can add or delete constituent elements, combine embodiments, or make design changes, or add, omit, or change processing conditions. As long as these modifications and alterations possess the essence of the present invention, they are also included within the scope of the present invention.

[0116] In the first embodiment of the present invention, an example is disclosed where the dummy nozzle 155 has the same shape as the droplet discharge nozzle 153, but the present invention is not limited thereto. The dummy nozzle 155 may also have a shape different from that of the droplet discharge nozzle 153. For example, it may be rectangular, conical, or semi-circular. In short, the dummy nozzle 155 only needs to have a shape that protrudes from the plate portion 151.

[0117] In the first embodiment of the present invention, it is disclosed that the distances d1 between adjacent droplet discharge nozzles, d2 between adjacent droplet discharge nozzles 153 and dummy nozzles 155, and d3 between adjacent dummy nozzles 155 are all the same, but the present invention is not limited thereto. The distances d1 between adjacent droplet discharge nozzles, d2 between adjacent droplet discharge nozzles 153 and dummy nozzles 155, and d3 between adjacent dummy nozzles 155 may also be different. For example, the distance d3 between adjacent dummy nozzles 155 may also be made smaller than the distances d1 between adjacent droplet discharge nozzles and d2 between adjacent droplet discharge nozzles 153 and dummy nozzles 155. This can improve the uniformity of the electric field. [Simplified Explanation of the Diagram]

[0026] Figure 1 is a schematic diagram of a droplet discharge device related to one embodiment of the present invention.

[0027] Figure 2 is a plan view and a cross-sectional view of a nozzle related to one embodiment of the present invention.

[0028] Figure 3 is a plan view of a nozzle related to one embodiment of the present invention.

[0029] Figure 4 is a perspective view of a droplet discharge nozzle related to one embodiment of the present invention.

[0030] Figure 5 is a top view and a cross-sectional view of a droplet discharge nozzle related to one embodiment of the present invention.

[0031] Figure 6 is a perspective view of a pseudo-nozzle related to one embodiment of the present invention.

[0032] Figure 7 is a top view and cross-sectional view of a pseudo-nozzle related to one embodiment of the present invention.

[0033] Figure 8 is a manufacturing process diagram of a nozzle related to one embodiment of the present invention.

[0034] Figure 9 is a manufacturing process diagram of a nozzle related to one embodiment of the present invention.

[0035] Figure 10 is a plan view and a cross-sectional view of a nozzle related to one embodiment of the present invention.

[0036] Figure 11 is a plan view and a cross-sectional view of a nozzle related to one embodiment of the present invention.

[0037] Figure 12 is a top view and a cross-sectional view of a pseudo-nozzle related to one embodiment of the present invention.

[0038] Figure 13 is a top view and a cross-sectional view of a pseudo-nozzle related to one embodiment of the present invention.

[0039] Figure 14 is an electron microscope photograph of the droplet discharge nozzle in a nozzle manufactured using one embodiment of the present invention.

[0040] Figure 15 is an optical microscope photograph of droplets ejected using the nozzle of Example 1.

[0041] Figure 16 is a diagram showing the size of the droplets ejected by the nozzle of Example 1.

[0042] Figure 17 is an optical microscope photograph of droplets ejected using the nozzle of the comparative example.

[0043] Figure 18 is a diagram showing the size of the droplets ejected by the nozzle of the comparative example.

Claims

1. A nozzle comprising a plate portion having a through hole, a droplet discharge nozzle portion having a plurality of droplet discharge nozzles disposed corresponding to the through hole of the plate portion and including a plurality of droplet discharge nozzles for discharging droplets by electrostatic discharge, and a pseudo-nozzle portion having a plurality of pseudo-nozzles disposed around the periphery of the droplet discharge nozzle portion in the plate portion and including a plurality of pseudo-nozzles with closed front ends, wherein the droplet discharge nozzles and the pseudo-nozzles have a tapered shape, and the inner diameter of the opening portion at the front end of the droplet discharge nozzles is 20 mm. The first height from the plate portion to the front end of the aforementioned dummy nozzle is lower than the second height from the plate portion to the front end of the aforementioned droplet discharge nozzle. The aforementioned plurality of droplet discharge nozzles are arranged side by side along the first direction and the second direction intersecting the first direction. The aforementioned dummy nozzle portion is arranged in a manner that surrounds the aforementioned droplet discharge nozzle portion. The aforementioned dummy nozzles are arranged side by side on both sides of the aforementioned first direction and both sides of the aforementioned second direction in a manner that corresponds to each of the aforementioned plurality of droplet discharge nozzles arranged on the outer side. The number of the aforementioned dummy nozzles in each row arranged on one side of the aforementioned first direction and one side of the aforementioned second direction is more than 2 and less than 30.

2. The nozzle as described in claim 1, wherein the aforementioned plurality of dummy nozzles are arranged as a whole in a range of 1 mm or more and 5 mm or less from the outermost dummy nozzle toward the aforementioned first direction.

3. The nozzle as claimed in claim 1, wherein the first distance between adjacent droplet discharge nozzles is the same as the second distance between adjacent dummy nozzles.

4. The nozzle as claimed in claim 1, wherein the aforementioned dummy nozzle is filled with a filler made of a metallic or conductive material.

5. A droplet discharge device comprising a nozzle as described in any one of claims 1 to 4.

6. A method for manufacturing a nozzle, comprising preparing a first recess group having a first surface and a second surface opposite to the first surface, including a first recess group having a plurality of first recesses on the side of the first surface and a second recess group having a plurality of second recesses disposed around the first recess group; forming a plurality of first structures with open front ends in the bottom of the first recesses by electrolytic casting; forming a plurality of second structures with closed front ends in the second recesses by electrolytic casting; and forming a planar third structure in the first surface to shield the plurality of first recesses. A photoresist mask is formed by the aforementioned structure and multiple second structures. A fourth structure is formed on the aforementioned third structure. The photoresist mask is removed, and the aforementioned first, second, third, and fourth structures are demolded from the aforementioned parent mold. A droplet discharge nozzle is formed from the aforementioned first structure, a dummy nozzle is formed from the aforementioned second structure, and a plate portion is formed from the aforementioned third and fourth structures. The droplet discharge nozzle and the dummy nozzle have a tapered shape, and the inner diameter of the opening at the front end of the droplet discharge nozzle is 20 mm. The first height from the plate portion to the front end of the aforementioned dummy nozzle is lower than the second height from the plate portion to the front end of the aforementioned droplet discharge nozzle. The aforementioned plurality of droplet discharge nozzles are formed in parallel along the first direction and the second direction intersecting the first direction. The aforementioned dummy nozzles are formed in a manner that surrounds the aforementioned droplet discharge nozzles. The aforementioned dummy nozzles are formed in parallel on both sides of the aforementioned first direction and both sides of the aforementioned second direction in a manner that corresponds to each of the aforementioned plurality of droplet discharge nozzles formed on the outer side. The number of the aforementioned dummy nozzles in each row formed on one side of the aforementioned first direction and one side of the aforementioned second direction is more than 2 and less than 30.

7. The method of manufacturing a nozzle as described in claim 6, wherein an insulating layer is exposed at the bottom of the aforementioned first recess.

8. The method of manufacturing a nozzle as claimed in claim 7, wherein the aforementioned plurality of dummy nozzles are formed integrally from the outermost dummy nozzle in a range of 1 mm or more and 5 mm or less in the aforementioned first direction.

9. A method of manufacturing a nozzle as claimed in claim 7, wherein the first distance between adjacent droplet discharge nozzles is the same as the second distance between adjacent dummy nozzles.

10. A method for manufacturing a nozzle as described in claim 6, wherein the aforementioned dummy nozzle is filled with a filler made of a metallic or conductive material.

Images