Nozzle head, method of manufacturing nozzle head, and liquid droplet ejection device

Abstract

A nozzle head includes a plate portion provided in a plate shape, a droplet ejection nozzle portion provided on the plate portion, including a plurality of droplet ejection nozzles that eject droplets in an electrostatic ejection manner, and a dummy nozzle portion provided on the plate portion and provided around the droplet ejection nozzle portion, including a plurality of dummy nozzles. In the nozzle head, the plurality of droplet ejection nozzles can be provided side by side in a first direction, and the dummy nozzle portion can be provided on both sides of the droplet ejection nozzle portion.

Description

Technical Field

[0001] This invention relates to a nozzle head, a method for manufacturing the nozzle head, and a droplet ejection device. Background 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 application. Previously, inkjet printing technologies primarily used piezoelectric inkjet heads, which eject droplets through mechanical pressure or vibration. However, electrostatic inkjet heads, capable of ejecting even finer droplets, have attracted attention. Patent Document 1 discloses an electrostatic inkjet recording device.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 10-34967 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Recently, multi-nozzle technology has been developed for electrostatic inkjet printhead applications to improve productivity. However, in the case of multi-nozzle systems, the diameters of the nozzles may be uneven. When the nozzle diameters are uneven, droplets cannot be evenly ejected onto the object. As a result, it is difficult to form a uniform image.

[0008] Therefore, one of the objectives of this invention is to provide a multi-nozzle system with high jet uniformity and a droplet jetting device having the multi-nozzle system.

[0009] means for solving problems

[0010] According to one embodiment of the present invention, a nozzle head is provided, comprising: a plate portion having a through hole; a droplet ejection nozzle portion disposed corresponding to the through hole of the plate portion, including a plurality of droplet ejection nozzles for ejecting droplets in an electrostatic ejection manner; and a simulated nozzle portion disposed around the droplet ejection nozzle portion in the plate portion, and including a plurality of simulated nozzles with their front ends closed.

[0011] In the nozzle head, a plurality of droplet ejection nozzles may be arranged side by side in a first direction, and the simulated nozzle portion may be arranged on both sides of the droplet ejection nozzle portion in the first direction.

[0012] In the nozzle head, a plurality of the simulated nozzles may be arranged on the entire area ranging from 1 mm to 5 mm from the simulated nozzle arranged on the outermost side toward the first direction.

[0013] In the nozzle head, the simulated nozzle section may include more than five simulated nozzles on both sides of the droplet ejection nozzle section in the first direction.

[0014] In the nozzle head, the first distance between adjacent droplet ejection nozzles can be the same as the second distance between adjacent simulated nozzles.

[0015] In the nozzle head, a plurality of droplet ejection nozzles may be arranged side by side in a first direction and in a second direction intersecting the first direction, and the simulated nozzle portion may be configured to surround the droplet ejection nozzle portion.

[0016] In the nozzle head, the simulated nozzles can be arranged side by side on both sides of the first direction and both sides of the second direction, corresponding to each of the multiple droplet ejection nozzles arranged on the outer side. The number of simulated nozzles in each column arranged on one side of the first direction and one side of the second direction can be more than 2 and less than 30.

[0017] In the nozzle head, the simulated nozzle may have a frame shape.

[0018] In the nozzle head, the first height from the plate portion to the front end of the simulated nozzle can be lower than the second height from the plate portion to the front end of the droplet ejection nozzle.

[0019] According to one embodiment of the present invention, a droplet ejection device including the nozzle head is provided.

[0020] According to one embodiment of the present invention, a method for manufacturing a nozzle head is provided, comprising: preparing a master mold having a first surface and a second surface located on the opposite side of the first surface, and including a first recess group having a plurality of first recesses on the first surface side and a second recess group disposed around the first recess group and having a plurality of second recesses; forming a plurality of first structures with front openings in the first recesses, forming a plurality of second structures with front closings in the second recesses, and forming a planar third structure on the first surface; forming an anti-corrosion mask to cover the plurality of first structures and the plurality of second structures; forming a fourth structure on the third structure; and demolding the first structure, the second structure, the third structure, and the fourth structure from the master mold by removing the anti-corrosion mask, thereby forming a droplet jet nozzle from the first structure, a simulated nozzle from the second structure, and a plate portion from the third structure and the fourth structure.

[0021] In the nozzle head, an insulating layer may be exposed at the bottom of the first recess.

[0022] In the nozzle, a plurality of droplet ejection nozzles may be formed side by side in a first direction, and a plurality of simulated nozzles may be formed on both sides of the droplet ejection nozzles in the first direction.

[0023] In the nozzle head, a plurality of the simulated nozzles may be formed on a whole within a range of more than 1 mm and less than 5 mm from the simulated nozzle disposed on the outermost side toward the first direction.

[0024] In the nozzle head, the simulated nozzles can be formed in more than five forms on both sides of the droplet ejection nozzle.

[0025] In the nozzle head, the first distance between adjacent droplet ejection nozzles can be the same as the second distance between adjacent simulated nozzles.

[0026] In the nozzle head, a plurality of droplet ejection nozzles are arranged side by side in a first direction and in a second direction intersecting the first direction, and the simulated nozzles may be configured to surround the droplet ejection nozzles.

[0027] In the nozzle head, the simulated nozzles can be arranged side by side on both sides of the first direction and both sides of the second direction, corresponding to each of the multiple droplet ejection nozzles formed on the outer side. The number of simulated nozzles in each row formed on one side of the first direction and one side of the second direction can be more than 2 and less than 30.

[0028] In the nozzle head, the simulated nozzle can be formed with a frame shape.

[0029] The effects of the invention

[0030] By using one embodiment of the present invention, a multi-nozzle system with high jet uniformity and a droplet jetting device having the multi-nozzle system can be provided. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a droplet ejection device according to one embodiment of the present invention.

[0032] Figure 2 This is a plan view and a cross-sectional view of a nozzle head according to one embodiment of the present invention.

[0033] Figure 3 This is an enlarged plan view of a nozzle head according to one embodiment of the present invention.

[0034] Figure 4 This is a perspective view of a droplet ejection nozzle according to one embodiment of the present invention.

[0035] Figure 5 The image shows a top view and a cross-sectional view of a droplet ejection nozzle according to one embodiment of the present invention.

[0036] Figure 6 This is a perspective view of a simulated nozzle according to one embodiment of the present invention.

[0037] Figure 7 The images show a top view and a cross-sectional view of a simulated nozzle according to one embodiment of the present invention.

[0038] Figure 8 This is a flowchart illustrating the manufacturing process of a nozzle head according to one embodiment of the present invention.

[0039] Figure 9 This is a flowchart illustrating the manufacturing process of a nozzle head according to one embodiment of the present invention.

[0040] Figure 10 This is a plan view and a cross-sectional view of a nozzle head according to one embodiment of the present invention.

[0041] Figure 11 This is a plan view and a cross-sectional view of a nozzle head according to one embodiment of the present invention.

[0042] Figure 12 The images show a top view and a cross-sectional view of a simulated nozzle according to one embodiment of the present invention.

[0043] Figure 13 The images show a top view and a cross-sectional view of a simulated nozzle according to one embodiment of the present invention.

[0044] Figure 14 Electron microscope image of a droplet ejection nozzle in a nozzle head manufactured using one embodiment of the present invention.

[0045] Figure 15 An optical microscope photograph of a droplet ejected using the nozzle head of Example 1.

[0046] Figure 16 A graph showing the size of droplets ejected using the nozzle head of Example 1.

[0047] Figure 17 An optical microscope photograph of a droplet ejected using a nozzle head from a comparative example.

[0048] Figure 18 A graph showing the size of droplets ejected using a nozzle head from a comparative example. Detailed Implementation

[0049] Hereinafter, various embodiments of the invention disclosed in this application will be described with reference to the accompanying drawings. However, the present invention can be implemented in various ways without departing from its spirit and is not limited to the description of the embodiments illustrated below.

[0050] Furthermore, in the accompanying drawings referenced in this embodiment, the same or similar reference numerals are given to the same parts or parts having the same function (reference numerals such as A, B, or -1, -2, etc. are added after the numbers), and sometimes repeated descriptions are omitted. In addition, for ease of explanation, the scale of the drawings may differ from the actual scale, or some structures may be omitted in the drawings.

[0051] Furthermore, in the detailed description of the present invention, when the positional relationship between a structure and another structure is specified, "above" and "below" not only include the case where it is located directly above or below a certain structure, but also include the case where other structures are inserted in between, unless otherwise stated.

[0052] <First Implementation Method>

[0053] (1-1. Structure of the droplet ejection device 100)

[0054] Figure 1 This is a schematic diagram of a droplet ejection device 100 according to one embodiment of the present invention.

[0055] 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 an object holding unit 160.

[0056] 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 circuits. The control unit 110 uses a pre-set droplet ejection program to control the ejection process of the droplet ejection unit 140.

[0057] The storage unit 115 functions as a database for storing the droplet ejection program and various information used in the droplet ejection program. The storage unit 115 uses memory, SSD (Solid State Disk), or other storage elements.

[0058] 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 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 (1000V in this example) to the droplet ejection unit 140. Alternatively, a constant voltage can be applied, but not limited to a pulsed voltage. The liquid held in the ink cartridge 145 is ejected from the front end 153a (see reference 153a) of the droplet ejection nozzle 153 in the nozzle head 150 by the voltage applied from the power supply unit 120 to the nozzle head 150. Figure 2 (B) is sprayed as a droplet toward the object 200 in the direction of (third direction D3).

[0059] The drive unit 130 comprises a motor, belt, gears, and other drive components. Based on instructions from the control unit 110, the drive unit 130 moves the droplet ejection unit 140 (more specifically, the nozzle head 150 described later) relative to the object holding unit 160 in one direction (in this example, the second direction D2). The drive unit 130 can fix the droplet ejection unit 140 to move the object. Furthermore, the drive unit 130 can be used in conjunction with a goniometer stage and can fine-tune the position of the nozzle head 150.

[0060] The droplet ejection unit 140 includes an ink cartridge 145 and a nozzle head 150. The nozzle head 150 uses an electrostatic inkjet nozzle. Details of the nozzle head 150 will be described later. The nozzle head 150 is used while being fixed to a bracket and accessory (not shown). The bracket and accessory may have a recess (elongated hole) for temporarily storing ink supplied from the ink cartridge 145 in a portion corresponding to the droplet ejection nozzle 153.

[0061] The object holding part 160 has the function of holding the object 200. In this example, the object holding part 160 uses a stage. The mechanism by which the object holding part 160 holds the object 200 is not particularly limited and a general holding mechanism is used. In this example, the object 200 is vacuum-adsorbed onto the object holding part 160. Furthermore, not limited to this, the object holding part 160 can use a fixing tool to hold the object 200.

[0062] (1-2. Structure of nozzle head 150)

[0063] The structure of nozzle head 150 will be described in detail below. Figure 2 (A) in the figure is a plan view of nozzle head 150. Figure 2 (B) is a cross-sectional view of nozzle head 150 between C1 and C2. Figure 3 This is an enlarged view of the plan view of nozzle head 150. Figure 4 This is a perspective view of the droplet ejection nozzle 153. Figure 5(A) in the image is a top view of the droplet jet nozzle 153. Figure 5 (B) is a cross-sectional view between A1 and A2 in the droplet jet nozzle 153. Figure 6 This is a 3D view simulating nozzle 155. Figure 7 (A) in the image is a top view of the simulated nozzle 155. Figure 7 (B) in the figure is a cross-sectional view between B1 and B2 in the simulated nozzle 155.

[0064] like Figure 2 (A) and Figure 2 As shown in (B), the nozzle head 150 includes a plate portion 151, a droplet ejection nozzle portion 152, and a simulated nozzle portion 154.

[0065] The plate portion 151 is plate-shaped. 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 appropriately set. In this example, the thickness of the plate portion is 10 μm or more and 100 μm or less.

[0066] like Figure 4 , Figure 5 (A) and Figure 5 As shown in (B), a droplet ejection nozzle section 152 is provided on one side of the plate section 151. The droplet ejection nozzle section 152 includes a plurality of droplet ejection nozzles 153. The droplet ejection nozzles 153 are arranged side by side in the first direction D1. In this embodiment, droplet ejection nozzles 153-1, 153-2, ..., 153-(N-1) and 153-N are provided on the plate section 151. N is a natural number greater than or equal to 20. In this example, N = 21. Furthermore, since it is not necessary to describe the droplet ejection nozzles 153-1, 153-2, ..., 153-(N-1) and 153-N separately, they will be described as droplet ejection nozzles 153. The droplet ejection nozzles 153 are made of a metal material such as nickel. The droplet ejection nozzles 153 have a conical shape.

[0067] The plate portion 151 has a through hole 151o in the portion (overlapping portion) corresponding to the droplet ejection nozzle 153. The inner diameter r151o of this through hole is larger than the inner diameter r153a of the ejection port (the opening portion 153ao of the front end portion 153a of the droplet ejection nozzle 153). The inner diameter of the through hole in 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 ejection nozzle 153 can be several hundred nm or more and 50 μm or less, preferably 1 μm or more and 30 μm or less, more preferably 5 μm or more and 20 μm or less. In this embodiment, voltage can be applied to the droplet ejection nozzle 153, voltage can be applied to the plate portion 151 (or ink cartridge 145), and voltage can be applied to the ink. When voltage is applied to the plate portion 151 and the droplet ejection nozzle 153, electrodes can be provided. The electrodes can include tungsten, nickel, molybdenum, titanium, gold, silver, copper, platinum, etc. At this time, multiple electrodes can be provided so that voltage is applied evenly to the entire plate portion 151. In addition, although this embodiment shows an example of applying voltage to the droplet ejection nozzle 153, the plate portion 151 or the ink, voltage can also be applied to the clamp (e.g., bracket or accessory) holding the nozzle head 150.

[0068] like Figure 2As shown, a simulated nozzle section 154 is disposed on the same surface as the droplet ejection nozzle section 152 in the plate section 151. The simulated nozzle section 154 includes a plurality of simulated nozzles 155. The simulated nozzle section 154 is disposed around the droplet ejection nozzle section 152. In this example, the simulated nozzle section 154 is disposed on both sides of the droplet ejection nozzle section 152 in the first direction D1. Furthermore, the plurality of simulated nozzles 155 can be disposed in a defined area starting from the outermost simulated nozzle 155 (simulated nozzle 155-1). From the viewpoint of the electric field strength of the surrounding area, the plurality of simulated nozzles 155 can also be disposed on the entire area of ​​1 mm to 5 mm (preferably 2 mm) from the outermost simulated nozzle 155 toward the first direction D1. In this case, the number of simulated nozzles 155 disposed on one side of the droplet ejection nozzle section 152 in the first direction D1 can be more than 1 / 5 of the number of droplet ejection nozzles 153. For example, the number of simulated nozzles 155 provided on one side of the droplet ejection 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 simulated nozzle 155L containing 5 simulated nozzles 155 (simulated nozzles 155-L1 to 155-L5) is provided on the left side of the droplet ejection nozzle section 152, which contains 21 droplet ejection nozzles 153. Similarly, a right simulated nozzle 155R containing 5 simulated nozzles 155 (simulated nozzles 155-R1 to 155-R5) is provided on the right side of the droplet ejection nozzle section 152. Furthermore, since it is not necessary to describe them separately as simulated nozzles 155-L1 to 155-L5, they will be described as simulated nozzles 155.

[0069] like Figure 3 As shown, the distances between adjacent droplet ejection nozzles (the distance between droplet ejection nozzle 153-1 and droplet ejection nozzle 153-2) D1, the distances between adjacent droplet ejection nozzle 153 and simulated nozzle 155 (the distance between droplet ejection nozzle 153-1 and simulated nozzle 155-L5) D2, and the distances between adjacent simulated nozzles 155 (the distance between simulated nozzle 155-L4 and simulated nozzle 155-L5) D3 are all the same. In this example, the distances D1, D2, and D3 between each nozzle are 200 μm.

[0070] like Figure 6 and Figure 7As shown in (B), the front end 155a of the simulated nozzle 155 does not have an opening and is closed. Therefore, the simulated nozzle 155 does not eject droplets. The simulated nozzle 155 uses the same material as the droplet ejection nozzle 153. The simulated nozzle 155 may have the same shape as the droplet ejection nozzle 153. In this case, the height H155 of the simulated nozzle 155 (also called the first height, specifically, the height from the upper surface 151a of the plate portion 151 to the front end 155a of the simulated nozzle 155) may also be the same as the height H153 of the droplet ejection nozzle 153 (also called the second height, specifically, the height from the upper surface 151a of the plate portion 151 to the front end 153a of the droplet ejection nozzle 153).

[0071] Here, when using a nozzle head containing multiple nozzles to eject droplets via electrostatic jetting, the electric field in the area surrounding the plate sometimes increases compared to the center of the plate. In the case of the nozzle head 150 of this embodiment, a simulated nozzle section 154 is disposed around the droplet ejection nozzle section 152. That is, multiple simulated nozzles 155 are disposed in the area where the electric field increases. Since the front ends of the multiple simulated nozzles 155 are closed, no droplets are ejected. On the other hand, the electric field in the area where the droplet ejection nozzles 153 are disposed becomes uniform. As a result, the size of the droplets ejected from each droplet ejection nozzle 153 can be made uniform.

[0072] (1-3. Manufacturing method of nozzle head 150)

[0073] The manufacturing method of nozzle head 150 is illustrated with the accompanying drawings. Figure 8 (A) to (D) Figure 9 (A) to (C) in the figure are cross-sectional views showing the manufacturing process of the nozzle head.

[0074] First, such as Figure 8 As shown in (B), a master mold 2000 is prepared for forming a droplet jet nozzle 153 and a simulated nozzle 155. In this embodiment, the concave master mold 2000 has a first surface 2000A and a second surface 2000B opposite to the first surface 2000A. The master mold 2000 includes a first master mold 2001 and a second master mold 2005. In addition, a first recess group 2006 is provided on the first surface 2000A side, which has a plurality of first recesses 2007 for forming the droplet jet nozzle; and a second recess group 2008 is provided around the first recess group 2006 and has a plurality of second recesses 2009 for forming the simulated nozzle.

[0075] A master mold 2000 is formed through film formation, photolithography, and etching. Specifically, a first master mold 2001 is prepared in the form of a plate. The first master mold 2001 can be a metal substrate or a material on which a conductive film is formed on the upper surface of an insulating substrate or a semiconductor substrate. Figure 8 As shown in (A), an insulating layer 2003 is formed on the portion of the upper surface of the first mold 2001 where the droplet injection nozzle 153 is formed. Next, as... Figure 8 As shown in (B), a second mold 2005 made of metal material is formed on the first mold 2001. The second mold 2005 can also be formed by photolithography and etching after the metal layer is formed. At this time, the insulating layer 2003 is exposed at the bottom of the first recess 2007. The first mold 2001 is exposed at the bottom of the second recess 2009.

[0076] Furthermore, while the above description illustrates an example of forming an insulating layer 2003 in the portion forming the droplet jet nozzle 153, the invention is not limited thereto. 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 catalyst layer may be formed in the exposed portion of the insulating layer 2003 in the region forming the simulated nozzle 155. Additionally, the second master mold 2005 may also be bonded to the first master mold 2001.

[0077] Next, as Figure 8 As shown in (C), multiple structures 1531 (also referred to as first structures) are formed in the first recess 2007 by electrolytic casting (electroplating), multiple structures 1551 (also referred to as second structures) are formed in the second recess 2009, and a planar structure 1511 (also referred to as third structure) is formed on the first surface 2000A. Structures 1531, 1551, and 1511 are formed at the same time. Structure 1551 is formed around structure 1531. In this example, it is formed on both sides of the group of structures 1531.

[0078] At this time, as Figure 8 As shown in (B), the insulating layer 2003 is exposed at the bottom 2007B of the first recess 2007. Therefore, since the insulating layer 2003 is present at the front end of the structure 1531, electrolytic casting is not performed. Therefore, the front end 1531a of the structure 1531 is perforated. Thus, a droplet ejection nozzle 153 with an opening 153aao is formed at the front end 153a. On the other hand, at the front end of the structure 1551, since the upper surface of the first master mold 2001 is exposed (where a catalyst layer or conductive film exists), electrolytic casting is performed. Therefore, the front end of the structure 1551 is closed. Thus, a simulated nozzle 155 is formed.

[0079] Next, as Figure 8 As shown in (D), the resist mask 2011 is formed on the portion corresponding to the front end 153a of the droplet jet nozzle 153 (specifically, the front end 1531a) and the portion corresponding to the front end 155a of the simulated nozzle 155 (specifically, the front end 1551a). Next, as... Figure 9 As shown in (A), structure 1513 is formed on the exposed portion of structure 1511 by electrolytic casting. After forming structure 1513, the resist mask 2011 is removed. Figure 9 (B) in the middle.

[0080] Finally, as Figure 9 As shown in (C), structures 1511, 1513, 1531, and 1551 are removed from the master mold 2000 (demolding). Thus, plate portion 151 is formed by structures 1511 and 1513. Droplet injection nozzle 153 is formed by structure 1531. Simulated nozzle 155 is formed by structure 1551. Therefore, nozzle head 150 can be manufactured.

[0081] As described above, when a structure is formed on the master mold 2000 using an electrolytic casting method, the electric field in the end region of the master mold 2000 is prone to becoming non-uniform. However, in the case of this embodiment, the end region of the master mold 2000 is the region where the simulated nozzle is formed. Therefore, the electric field in the region where the droplet injection nozzle 153 is formed is uniform. Thus, it is possible to make the shape of the droplet injection nozzle 153 and the opening shape of the front end portion 153a uniform.

[0082] Therefore, by using this embodiment, the shapes of the multiple droplet ejection nozzles become uniform. Thus, the ejection uniformity of the multiple droplet ejection nozzles can be improved.

[0083] <Second Implementation Method>

[0084] In this embodiment, a nozzle head 150A, which differs from that in the first embodiment, will be described. Specifically, an example in which the simulated nozzle section is arranged to surround the droplet ejection nozzle will be described. In addition, for ease of explanation, some components will be omitted from the description.

[0085] (2-1. Structure of Nozzle Head 150A)

[0086] Figure 10 (A) in the figure is a plan view of nozzle head 150A. Figure 10 (B) in the diagram is a cross-sectional view of nozzle head 150A between C1 and C2. For example... Figure 10 (A) and Figure 10 As shown in (B), the nozzle head 150A includes a plate portion 151, a droplet ejection nozzle portion 152A, and a simulated nozzle portion 154A.

[0087] A droplet ejection nozzle section 152A is disposed on one surface of the plate section 151. The droplet ejection nozzle section 152A includes a plurality of droplet ejection nozzles 153A. The droplet ejection nozzles 153A are arranged side by side in a first direction D1 and a second direction D2 that intersects (orthogonally to) the first direction D1. In this example, the droplet ejection nozzle section 152A includes 4 rows × 100 columns = 400 droplet ejection nozzles.

[0088] like Figure 10 (A) and Figure 10 As shown in (B), a simulated nozzle section 154A is disposed on the same surface as the droplet ejection nozzle section 152A in the plate section 151. The simulated nozzle section 154A includes a plurality of simulated nozzles 155A. The simulated nozzle section 154A is disposed around the droplet ejection nozzle section 152A. In this example, the simulated nozzle section 154A is disposed in a manner that surrounds the droplet ejection nozzle section 152A. The number of simulated nozzles disposed in each column on both sides (left and right sides) of the first direction D1 and both sides (top and bottom sides) of the second direction D2 can be more than 2 and less than 30. Specifically, 5 columns of simulated nozzles 155A are disposed on the left and right sides of the droplet ejection nozzle section 152A. In addition, two rows of simulated nozzles 155A are disposed on the top and bottom sides of the droplet ejection nozzle section 152A. Furthermore, when the droplet ejection nozzle section 152A includes 1,000 rows × 1,000 columns = 1,000,000 droplet ejection nozzles, 20 rows (columns) of simulated nozzles 155A can be arranged on each of the top, bottom, left, and right sides. In this case, the multiple simulated nozzles 155A can have a 10 μm interval between the outermost simulated nozzle 155 (simulated nozzle 155-1) and the adjacent simulated nozzle 155A.

[0089] By using this embodiment, the shapes of the multiple droplet ejection nozzles become uniform. Therefore, the ejection uniformity of the multiple droplet ejection nozzles can be improved.

[0090] <Third Implementation Method>

[0091] In this embodiment, a nozzle head that differs from the first and second embodiments will be described. Specifically, an example of a simulated nozzle arranged in a frame shape will be described. Furthermore, portions that overlap with the first and second embodiments will be omitted from the description as appropriate.

[0092] (3-1. Structure of Nozzle Head 150B)

[0093] Figure 11 (A) in the figure is a plan view of nozzle head 150B. Figure 11 (B) in the diagram is a schematic cross-sectional view of nozzle head 150B between C1 and C2. For example... Figure 11(A) and Figure 11 As shown in (B), the nozzle head 150B includes a plate portion 151, a droplet ejection nozzle portion 152B, and a simulated nozzle portion 154B.

[0094] A droplet ejection nozzle section 152B is disposed on one surface of the plate section 151. The droplet ejection nozzle section 152B includes a plurality of droplet ejection nozzles 153B. The droplet ejection nozzles 153B are arranged side by side in a first direction D1 and a second direction D2 intersecting the first direction D1. In this example, the droplet ejection nozzle section 152B includes 4 rows × 100 columns = 400 droplet ejection nozzles.

[0095] like Figure 11 (A) and Figure 11 As shown in (B), a simulated nozzle portion 154B is disposed on the same surface as the droplet ejection nozzle portion 152B in the plate portion 151. The simulated nozzle portion 154B includes a plurality of simulated nozzles 155B. The simulated nozzle portion 154B is disposed around the droplet ejection nozzle portion 152B. In this example, the simulated nozzle portion 154B is disposed in a manner that surrounds the droplet ejection nozzle portion 152B. Specifically, four simulated nozzles 155B with a frame shape surrounding the droplet ejection nozzle portion 152B are provided. At this time, as... Figure 11 As shown in (B), the simulated nozzle 155B can have a rectangular shape or a tapered shape facing the front end.

[0096] By using this embodiment, the shapes of the multiple droplet ejection nozzles become uniform. Therefore, the ejection uniformity of the multiple droplet ejection nozzles can be improved.

[0097] <Fourth Implementation Method>

[0098] In the first embodiment of the present invention, an example is shown where the height H155 of the simulated nozzle 155 is the same as the height H153 of the droplet ejection nozzle 153, but the present invention is not limited thereto. In this embodiment, a nozzle head different from that in the first embodiment will be described. Specifically, examples of droplet ejection nozzle heights that differ from the height of the simulated nozzle will be described. In addition, parts that are repeated in the first and second embodiments will be appropriately omitted in the description.

[0099] Figure 12 (A) in the image is a top view of the simulated nozzle 155C. Figure 12 (B) in the diagram is a cross-sectional view between B1 and B2 in the simulated nozzle 155C. The height H155C of the simulated nozzle 155C can be lower than the height H153 of the droplet ejection nozzle 153. Therefore, it will not become an obstacle when the droplet ejection nozzle 153 ejects droplets. Thus, by using one embodiment of the present invention, droplet ejection can be stably achieved.

[0100] <Fifth Implementation Method>

[0101] In this embodiment, a nozzle head different from that in the first embodiment will be described. Specifically, an example of filling a simulated nozzle with filler will be described. Furthermore, parts that overlap with those in the first and second embodiments will be omitted from the description as appropriate.

[0102] Figure 13 (A) in the image is a top view of the simulated nozzle 155D. Figure 13 (B) in the figure is a cross-sectional view between B1 and B2 in the simulated nozzle 155D. The simulated nozzle 155D can also be filled with filler 157. Filler 157 can be provided only in the front end of the simulated nozzle 155, or it can be filled into the plate portion 151. In this case, a material different from the ink material can be filled into the simulated nozzle 155D. In this example, resin material is filled into the simulated nozzle 155. In addition to resin material, glass material and ceramic material can also be used as filler 157. Furthermore, the electric field formed may vary depending on the filler material. Therefore, from the perspective of uniform electric field, metallic or conductive materials can be used as filler. In addition, the filler 157 can also be a liquid in which the jetting force caused by the electric field is ineffective, such as a nonpolar solvent, organosilicon, hydrocarbon solvent, or ionic liquid. By using this embodiment, droplets can be jetted stably.

[0103]

Example

[0104] Hereinafter, an embodiment of the nozzle head according to one embodiment of the present invention will be described.

[0105] <1. Structure of the Nozzle Head>

[0106] Hereinafter, a nozzle head having a simulated nozzle and a nozzle head without a simulated nozzle as a comparative example will be described using one embodiment of the present invention.

[0107] (Nozzle head of Example 1)

[0108] The structure of the nozzle head in Example 1 is as follows.

[0109] Droplet ejection nozzles: 21 x 1 column

[0110] Simulated nozzle: There are 5 nozzles on both sides of the droplet ejection nozzle.

[0111] The nozzle head of Example 1 is formed by electrolytic casting and bonded to the bracket.

[0112] Figure 14 An electron microscope image of a droplet ejection nozzle. (e.g.) Figure 14As shown, the droplet ejection nozzles are arranged in a row. The structure of the droplet ejection nozzles is as follows:

[0113] Distance between adjacent droplet ejection nozzles: 200 μm

[0114] Droplet ejection nozzle height: 50μm

[0115] Inner diameter of the tip of the droplet ejection nozzle: 20 μm

[0116] Inclination from the bottom to the front end of the droplet ejection nozzle: 20°

[0117] (Compare the nozzle heads in the example)

[0118] The structure of the nozzle head in the comparative example is as follows.

[0119] Droplet ejection nozzles: 100 units x 1 column

[0120] Simulated nozzle: None

[0121] The nozzle head of the comparative example is formed by electrolytic casting.

[0122] <2. Droplet Ejection Results>

[0123] Figure 15 An optical microscope photograph of a droplet ejected using the nozzle head of Example 1. Figure 16 A graph showing the size (diameter) of droplets ejected using the nozzle head of Example 1. Figure 17 An optical microscope photograph of a droplet ejected using a nozzle head from a comparative example. Figure 18 A graph showing the size (diameter) of droplets ejected using a nozzle head from a comparative example.

[0124] like Figure 17 and Figure 18 As shown, when using the nozzle head of the comparative example, the droplets ejected from the first droplet ejection nozzle were 43% larger than those ejected from the fifth droplet ejection nozzle. Furthermore, the droplets ejected from the 100th droplet ejection nozzle were 39% larger than those ejected from the 96th droplet ejection nozzle.

[0125] On the other hand, such as Figure 15 and Figure 16 As shown, when using the nozzle head of Example 1, the droplets ejected from the first droplet ejection nozzle are 13% larger than those ejected from the fourth droplet ejection nozzle. Furthermore, the droplets ejected from the 21st droplet ejection nozzle are 7% larger than those ejected from the 17th droplet ejection nozzle.

[0126] Therefore, by using the nozzle head of Embodiment 1 of the present invention, it was confirmed that the size of the ejected droplets can be made more uniform compared to the nozzle head of the comparative example.

[0127] (Modified Example)

[0128] It should be understood that, within the scope of the present invention, those skilled in the art can conceive of various modifications and alterations, and these modifications and alterations also fall within the scope of the present invention. For example, any appropriate additions, deletions, combinations, or design changes to the constituent elements of the described embodiments, or any additions, omissions, or conditional changes to the structures, as long as they possess the essential elements of the present invention, are included within the scope of the present invention.

[0129] In a first embodiment of the invention, an example is shown where the simulated nozzle 155 has the same shape as the droplet jet nozzle 153, but the invention is not limited thereto. The simulated nozzle 155 may have a different shape than the droplet jet nozzle 153. For example, it may have a rectangular shape, a conical shape, or a semi-circular shape. That is, the simulated nozzle 155 only needs to have a shape that protrudes from the plate portion 151.

[0130] In a first embodiment of the present invention, an example is shown where the distances D1 between adjacent droplet ejection nozzles, D2 between adjacent droplet ejection nozzles 153 and simulated nozzles 155, and D3 between adjacent simulated nozzles 155 are all the same; however, the present invention is not limited thereto. The distances D1 between adjacent droplet ejection nozzles, D2 between adjacent droplet ejection nozzles 153 and simulated nozzles 155, and D3 between adjacent simulated nozzles 155 may also be different. For example, the distance D3 between adjacent simulated nozzles 155 may be smaller than the distances D1 and D2 between adjacent droplet ejection nozzles 153 and simulated nozzles 155. Therefore, the uniformity of the electric field can be improved.

[0131] Explanation of reference numerals in the attached figures

[0132] 100: Droplet ejection device; 110: Control unit; 115: Storage unit; 120: Power supply unit; 130: Drive unit; 140: Droplet ejection unit; 145: Ink cartridge; 150: Nozzle head; 151: Plate part; 151a: Upper surface; 151o: Through hole; 152: Droplet ejection nozzle part; 153: Droplet ejection nozzle; 153a: Front end part; 153ao: Opening part; 154: Simulated nozzle part; 155: Simulated nozzle; 155a: Front end part. 157: Filler, 160: Object holding part, 200: Object, 1511: Structure, 1531: Structure, 1531a: Front end, 1533: Structure, 1551: Structure, 2000: Mold, 2001: First mold, 2003: Insulating layer, 2005: Second mold, 2006: First recess group, 2007: First recess, 2008: Second recess group, 2009: Second recess, 2011: Anti-corrosion mask.

Claims

1. A nozzle head, wherein, include: A plate section with through holes; The droplet ejection nozzle section is provided corresponding to the through hole of the plate section, and includes a plurality of droplet ejection nozzles that eject droplets in an electrostatic ejection manner; as well as A simulated nozzle section, disposed around the droplet ejection nozzle section in the plate section, includes multiple simulated nozzles with their front ends closed. The droplet ejection nozzle and the simulated nozzle have a conical shape. The inner diameter of the opening at the front end of the droplet ejection nozzle is less than 20 μm. The first height from the plate portion to the front end of the simulated nozzle is lower than the second height from the plate portion to the front end of the droplet ejection nozzle. The plurality of droplet ejection nozzles are arranged side by side in a first direction and in a second direction intersecting the first direction. The simulated nozzle section is configured to surround the droplet ejection nozzle section. The simulated nozzles are arranged side-by-side on both sides in the first direction and on both sides in the second direction, corresponding to the individual droplet ejection nozzles located on the outer side of the plurality of droplet ejection nozzles. The number of simulated nozzles in each column arranged on one side of the first direction and one side of the second direction is more than 2 and less than 30.

2. The nozzle head according to claim 1, wherein, The plurality of simulated nozzles are arranged on the entire area ranging from 1 mm to 5 mm from the outermost simulated nozzle toward the first direction.

3. The nozzle head according to claim 1, wherein, The first distance between adjacent droplet ejection nozzles is the same as the second distance between adjacent simulated nozzles.

4. The nozzle head according to claim 1, wherein, The simulated nozzle is filled with a filler made of metallic or conductive material.

5. A droplet ejection device, wherein, Includes the nozzle head as described in any one of claims 1 to 4.

6. A method for manufacturing a nozzle head, wherein, include: Prepare a master mold, the master mold having a first surface and a second surface located on the opposite side of the first surface, and including a first recess group having a plurality of first recesses on the first surface side and a second recess group disposed around the first recess group and having a plurality of second recesses. A plurality of first structures with open front ends are formed in the first recess, a plurality of second structures with closed front ends are formed in the second recess, and a planar third structure is formed on the first surface. A resist mask is formed to shield multiple first structures and multiple second structures; A fourth structure is formed on the third structure; as well as By removing the resist mask, the first structure, the second structure, the third structure, and the fourth structure are demolded from the master mold, thereby forming a droplet jet nozzle from the first structure, a simulated nozzle from the second structure, and a plate portion from the third and fourth structures. The droplet ejection nozzle and the simulated nozzle have a conical shape. The inner diameter of the opening at the front end of the droplet ejection nozzle is less than 20 μm. The first height from the plate portion to the front end of the simulated nozzle is lower than the second height from the plate portion to the front end of the droplet ejection nozzle. The plurality of droplet ejection nozzles are arranged side by side in a first direction and in a second direction intersecting the first direction. The simulated nozzle is configured to surround the droplet ejection nozzle. The simulated nozzles are arranged side-by-side on both sides of the first direction and both sides of the second direction, corresponding to the individual droplet ejection nozzles formed on the outer side of the plurality of droplet ejection nozzles. The number of simulated nozzles in each column formed on one side of the first direction and on one side of the second direction is more than 2 and less than 30.

7. The method for manufacturing a nozzle head according to claim 6, wherein, An insulating layer is exposed at the bottom of the first recess.

8. The method for manufacturing a nozzle head according to claim 6, wherein, The plurality of simulated nozzles are formed on the entire area ranging from 1 mm to 5 mm from the simulated nozzle disposed on the outermost side toward the first direction.

9. The method for manufacturing a nozzle head according to claim 6, wherein, The simulated nozzle is filled with a filler made of metallic or conductive material.

10. A method for manufacturing a nozzle head according to any one of claims 6 to 9, wherein, The first distance between adjacent droplet ejection nozzles is the same as the second distance between adjacent simulated nozzles.

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