Plating apparatus

Abstract

Provided is a plating device that improves the time required for plating and suppresses variations in the thickness of a plated film that is formed. A plating device is provided with: a plating tank for storing a plating solution; a cylindrical metal tube which is a first electrode and has a hollow portion; the cylindrical screen pipe is made of an insulating material and is provided with a hollow part; the metal tube, the screen tube, and the second electrode are accommodated in the plating tank, the metal tube is disposed in the hollow portion of the screen tube, a plating formation portion is formed between the inner side of the screen tube and the outer side of the metal tube, the second electrode is disposed on the outer side of the screen tube, and an upward flow for raising the plating liquid is generated in the hollow portion of the metal tube. The plating method is characterized in that the object to be plated rises in the hollow part of the metal tube along with the rising flow of the plating liquid, is discharged out of the metal tube, is stirred, is lowered in the plating formation part, and is plated by applying a current between the metal tube serving as the first electrode and the second electrode during the lowering, an auxiliary electrode electrically connected to the metal tube, which is a first electrode, is provided in the plating formation part.

Description

Technical Field

[0001] The present invention relates to a plating apparatus. Background Art

[0002] So-called jet-type plating apparatuses are widely used for forming external electrodes of electronic components, etc. Patent Document 1 (Japanese Patent Application Laid-Open No. 2021-138999) discloses a jet-type plating apparatus.

[0003] The plating device disclosed in Patent Document 1 includes a plating tank. A metal pipe (cathode) as a first electrode, a mesh pipe (partition wall) made of an insulating material, and a second electrode (anode) are housed in the plating tank.

[0004] A metal pipe is arranged inside the mesh pipe, and a plating forming part is formed between the inner side of the mesh pipe and the outer side of the metal pipe. The plating forming part refers to a region (space) where the plated object is plated. A second electrode is arranged outside the mesh pipe.

[0005] A jetting unit is provided under the metal pipe. The jetting unit is used to generate an upward flow of the plating solution inside the metal pipe. That is, in the device disclosed in Patent Document 1, the jetting unit is a source for generating a jet flow of the plating solution.

[0006] The plating apparatus disclosed in Patent Document 1 contains a plating solution, an object to be plated (eg, a main body of an electronic component), and a conductive medium in a plating tank, and further contains insulating balls to improve the fluidity of the object to be plated as needed.

[0007] The object to be plated, the dielectric, and the insulating balls rise in the metal pipe along with the rising flow of the plating solution generated in the metal pipe, and are ejected outward from the upper end of the metal pipe and stirred.

[0008] The stirred objects to be plated, dielectrics, and insulating balls are then deposited on the upper side of the plating forming portion. At this time, the plating forming portion is already full of other objects to be plated, dielectrics, and insulating balls. The objects to be plated, dielectrics, and insulating balls deposited on the upper side of the plating forming portion then gradually descend in the plating forming portion. At this time, a current is applied between the metal tube as the first electrode and the second electrode, thereby forming a plating film in the plating forming area (area where the base electrode, etc. are formed) on the surface of the object to be plated.

[0009] The plated object, dielectric, and insulating ball with the plated film formed thereon are pushed out from the lower end of the plated forming section, and rise again inside the metal tube along with the rising flow of the plating liquid generated inside the metal tube, and are ejected outward from the upper end of the metal tube and stirred. The plated object circulates in the plating device several to several thousand times until the predetermined thickness of the plated film is reached.

[0010] During plating on the object to be plated in the plating forming portion, the medium plays a role of electrically connecting the metal pipe as the first electrode and the plating forming region on the surface of the object to be plated.

[0011] Prior Art Literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent Application Publication No. 2021-138999 Summary of the invention

[0014] Problem that the invention aims to solve

[0015] In the plating step, the amount (volume) and size of the medium are appropriately adjusted depending on the desired state of the plated film and the like.

[0016] When the number of dielectrics is small, the diameter of the dielectrics is small, the plating formation area on the surface of the object to be plated is small, etc., the electrical connection between the metal tube as the first electrode and the plating formation area of ​​the object to be plated may not be sufficiently achieved. If the electrical connection between the metal tube as the first electrode and the plating formation area of ​​the object to be plated is not sufficiently achieved, it may take a long time to reach a predetermined thickness of the plated film, or the thickness of the formed plated film may vary among the objects to be plated.

[0017] Therefore, increasing the number of dielectrics has been studied. However, if the number of dielectrics is increased, the electric field will be shielded by the dielectrics. Due to the shielding of the electric field by the dielectrics, there is a concern that the film formation time will be prolonged or the plating thickness will vary.

[0018] Therefore, an object of the present invention is to solve the above-mentioned conventional problems and to provide a plating apparatus that improves the time required for plating and suppresses the thickness variation of the formed plated film.

[0019] Technical solutions to solve problems

[0020] In order to solve the above-mentioned conventional problems, a plating device according to one embodiment of the present invention comprises: a plating tank for storing a plating solution; a cylindrical metal tube, which is a first electrode and has a hollow portion; a cylindrical screen tube, which is made of an insulating material and has a hollow portion; and a second electrode. The metal tube, the screen tube and the second electrode are respectively accommodated in the plating tank, the metal tube is arranged in the hollow portion of the screen tube, a plating forming portion is formed between the inner side of the screen tube and the outer side of the metal tube, the second electrode is arranged on the outer side of the screen tube, an upward flow for raising the plating solution is generated in the hollow portion of the metal tube, an object to be plated rises in the hollow portion of the metal tube along with the upward flow of the plating solution, is discharged to the outside of the metal tube, and after being stirred, descends in the plating forming portion. During the descent, the object is plated by applying a current between the metal tube, which is the first electrode, and the second electrode, wherein an auxiliary electrode electrically connected to the metal tube, which is the first electrode, is provided in the plating forming portion.

[0021] Effects of the Invention

[0022] In the plating apparatus according to one embodiment of the present invention, since the auxiliary electrode assists the electrical connection between the metal pipe as the first electrode and the plating forming region of the object to be plated, the time required to reach a desired plating thickness can be improved.

[0023] In addition, in a plating device involved in one embodiment of the present invention, since the auxiliary electrode assists the electrical connection between the metal tube serving as the first electrode and the plating forming area of ​​the plated object, a uniform current can be supplied to the plating forming area, thereby suppressing the thickness deviation of the formed plating film. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a cross-sectional view of the plating apparatus 100 according to the first embodiment.

[0025] Figure 2 is a cross-sectional view of the plating apparatus 100, showing Figure 1 The single-dash arrow AA part.

[0026] Figure 3 (A) is a front view of main parts of the metal pipe 2 and the auxiliary electrode 15 of the plating apparatus 100 . Figure 3 (B) is a cross-sectional view of main parts of the metal pipe 2 and the auxiliary electrode 15 of the plating apparatus 100 . Figure 3 (C) is a plan view of main parts of the metal pipe 2 and the auxiliary electrode 15 of the plating apparatus 100 .

[0027] Figure 4 (A) is a front view of a main part of a metal pipe 2 of a plating apparatus 1100 according to a comparative example. Figure 4 (B) is a cross-sectional view of a main part of the metal pipe 2 of the plating apparatus 1100 . Figure 4 (C) is a plan view of the main parts of the metal pipe 2 of the plating device 1100 .

[0028] Figure 5 (A) is a graph showing the distribution (frequency) of the thickness of the plated film of Example 1 in Experiment 1. Figure 5 (B) is a graph showing the distribution (frequency) of the thickness of the plated film of Comparative Example 1 in Experiment 1.

[0029] Figure 6 This is a graph showing the variation in thickness of the plated films of Example 1 and Comparative Example 1 in Experiment 1.

[0030] Figure 7 It is a front view of the main part of the plating apparatus 200 according to the second embodiment.

[0031] Figure 8 (A) is a cross-sectional view of a main part of the plating apparatus 200A. Figure 8 (B) is a cross-sectional view of a main part of the plating apparatus 200B. Figure 8 (C) is a cross-sectional view of a main part of the plating apparatus 200C.

[0032] Fig. 9 This is a graph showing the variation in thickness of the plated films of Example 21, Example 22, and Example 23 in Experiment 2. DETAILED DESCRIPTION

[0033] The following, with the attached Figure 1 First, the mode for implementing the present invention will be described.

[0034] In addition, each embodiment illustratively shows an embodiment of the present invention, and the present invention is not limited to the contents of the embodiment. In addition, it is also possible to combine the contents recorded in different embodiments to implement, and the implementation contents in this case are also included in the present invention. In addition, the drawings are used to help the understanding of the specification, and are sometimes schematically depicted, and the ratio of the dimensions of the depicted constituent elements or constituent elements is sometimes inconsistent with the ratio of their dimensions recorded in the specification. In addition, there are cases where the constituent elements recorded in the specification are omitted in the drawings, and the number of elements is omitted and depicted, etc.

[0035] [First embodiment]

[0036] exist Figure 1 , Figure 2 , Figure 3 (A) to (C) show the plating apparatus 100 according to this embodiment. Figure 1 2 is a cross-sectional view of the plating apparatus 100 . Figure 2 is also a cross-sectional view of the plating apparatus 100, showing Figure 1 The AA portion is indicated by the single-dot dash arrow. Figure 3 (A) is a main part front view showing a metal pipe 2 and an auxiliary electrode 15 described later of the plating apparatus 100 . Figure 3 (B) is a cross-sectional view of the main parts of the metal pipe 2 and the auxiliary electrode 15 . Figure 3 (C) is a plan view of the main parts of the metal pipe 2 and the auxiliary electrode 15 .

[0037] The plating apparatus 100 includes a plating tank 1. The top of the plating tank 1 is open. The plating tank 1 is used to store a mixture 16 of a plating solution, an object to be plated, and a medium described later. Insulating balls may be added to the mixture 16 as necessary to improve the fluidity of the object to be plated.

[0038] The plating device 100 includes a cylindrical metal tube 2 inside a plating tank 1. The metal tube 2 has a hollow portion 2a. The metal tube 2 is a first electrode, and in the present embodiment, is a cathode electrode. In the present embodiment, the metal tube 2 is cylindrical. However, the metal tube 2 may also be a polygonal tube. The material of the metal tube 2 is arbitrary, and various metals may be used. The dimensions of the metal tube 2, such as the outer diameter, inner diameter, and length, are arbitrary and may be appropriately set.

[0039] In this embodiment, if Figure 3 As shown, two conductive rod-shaped support parts 2b are formed integrally with the metal pipe 2 at the upper part of the metal pipe 2. However, the number of the support parts 2b is arbitrary, and may be one or more than two.

[0040] The plating device 100 is provided with a screen tube 3 made of an insulating material inside the plating tank 1. The screen tube 3 has a hollow portion 3a. In the present embodiment, the screen tube 3 is cylindrical. However, the screen tube 3 may also be a polygonal cylindrical shape. The screen tube 3 is formed into a screen (mesh) shape that allows the plating solution to pass but does not allow the plated object, the medium, and the insulating ball to pass. The material of the screen tube 3 is arbitrary, for example, various resins can be used. The dimensions of the screen tube 3, such as the outer diameter, inner diameter, and length, are arbitrary and can be set appropriately.

[0041] The inner diameter of the mesh tube 3 is larger than the outer diameter of the metal tube 2. The metal tube 2 is arranged in the hollow portion 3a of the mesh tube 3. A plating forming portion 4 is formed between the inner side of the mesh tube 3 and the outer side of the metal tube 2. The plating forming portion 4 is a region (space) where the plated object is plated. Figure 1 , Figure 2 In FIG. 1 , the plating forming portion 4 is drawn in a grid shape. The area between the outer diameter of the metal pipe 2 and the inner diameter of the mesh pipe 3 is the plating forming portion 4. The dimensions such as the length of the plating forming portion 4 are arbitrary and can be set appropriately.

[0042] The object to be plated, the dielectric, and the insulating balls are accumulated inside the plating forming portion 4 and gradually fall downward. During the fall, the surface of the object to be plated is plated.

[0043] The plating device 100 includes a second electrode 5 inside the plating tank 1. In the present embodiment, the second electrode 5 is an anode electrode. In the present embodiment, the second electrode 5 includes a cylindrical metal. The second electrode 5 is arranged outside the mesh tube 3. The material of the second electrode 5 is arbitrary, and various metals can be used.

[0044] like Figure 2 As shown, regarding the plating device 100, when viewed in a planar direction, the metal pipe 2, the mesh pipe 3, and the second electrode 5 are arranged in a concentric circle shape so that their central axes coincide with each other. Therefore, the plating device 100 uniformly applies current between the metal pipe 2 as the first electrode and the second electrode 5 in any region of the plating forming portion 4, thereby suppressing the thickness deviation of the formed plated film.

[0045] The plating device 100 includes a jet unit 6 below the metal pipe 2. The jet unit 6 includes a jet port 6a. The jet port 6a jets the plating solution toward the hollow portion 2a of the metal pipe 2 to generate an upward flow of the plating solution inside the hollow portion 2a.

[0046] The plating device 100 includes a circulation line 7 formed of a pipe. One end of the circulation line 7 is connected to a liquid suction port 8 formed in the plating tank 1. The other end of the circulation line 7 is connected to an injection port 6a of the injection unit 6. A pump 9 and a filter 10 are provided in the middle of the circulation line 7. When the pump 9 is driven, the circulation line 7 sucks the plating solution from the liquid suction port 8 and injects the plating solution from the injection port 6a.

[0047] The plating device 100 includes a mixing section 11 below the metal pipe 2 and the mesh pipe 3 and above the injection section 6. The mixing section 11 is an area where the plating liquid injected from the injection port 6a of the injection section 6 and the plated object, the medium, and the insulating balls descending from the plating forming section 4 are mixed. In the present embodiment, the mixing section 11 contains an insulating material and has an inverted frustum-shaped indentation formed on the upper surface. In addition, the so-called inverted frustum refers to a frustum whose upper bottom surface is larger than the lower bottom surface. However, the shape of the indentation is arbitrary, and it can also be mortar-shaped instead of the inverted frustum. In addition, the injection section 6 is formed on the bottom surface of the indentation of the mixing section 11.

[0048] The plating device 100 is provided with a guide portion 12 above the metal pipe 2 and the screen pipe 3. In the guide portion 12, the plated object, the medium, and the insulating balls are stirred along with the rising flow of the plating liquid formed inside the hollow portion 2a of the metal pipe 2 by the injection from the injection port 6a of the injection portion 6 and discharged (sprayed) from the opening on the upper side of the hollow portion 2a of the metal pipe 2, and are guided to the area of ​​the plating forming portion 4 after being stirred. The guide portion 12 contains an insulating material and is in the shape of an inverted frustum. The upper end of the metal pipe 2 protrudes from the bottom surface of the guide portion 12. The upper end of the hollow portion 2a of the metal pipe 2 is open at the bottom surface of the guide portion 12. The bottom surface of the guide portion 12 is connected to the screen pipe 3.

[0049] The plating device 100 is provided with an insulating reflector 13 above the opening of the plating tank 1. The reflector 13 is sometimes called a guide plate. The reflector 13 plays a role in suppressing the scattering of the plating solution. In addition, a support portion 2b of the metal pipe 2 is mounted on the lower surface of the reflector 13. In addition, a cylindrical suppression plate 13a is formed on the lower surface of the reflector 13. The suppression plate 13a is arranged in the guide portion 12. The plating solution sometimes overflows from the upper edge of the guide portion 12, but the suppression plate 13a allows only the plating solution to overflow from the guide portion 12, thereby suppressing the overflow of the plated object, the dielectric, and the insulating ball.

[0050] The plating apparatus 100 includes a power source 14. One line of the power source 14 is connected to the support portion 2b of the metal pipe 2 as the first electrode, and the other line is connected to the second electrode 5. The power source 14 applies a current between the metal pipe 2 as the first electrode and the second electrode 5.

[0051] The plating device 100 is provided with an auxiliary electrode 15, which is an important structure in the present invention, in the plating forming part 4. The auxiliary electrode 15 is electrically connected to the metal tube 2, which is the first electrode. When the object to be plated is plated in the plating forming part 4, the auxiliary electrode 15 plays a role of assisting the metal tube 2, which is the first electrode. More specifically, when the object to be plated is plated in the plating forming part 4, the metal tube 2, which is the first electrode, and the plating forming area of ​​the object to be plated are electrically connected via a conductive path formed by a plurality of media. In the plating device 100, since the auxiliary electrode 15 electrically connected to the metal tube 2, which is the first electrode, is provided, the power supply points are increased, and the electrical connection between the metal tube 2, which is the first electrode, and the plating forming area of ​​the object to be plated becomes more reliable.

[0052] In the present embodiment, the auxiliary electrode 15 is in a plate shape. However, the shape of the auxiliary electrode 15 is arbitrary and is not limited to the plate shape. The auxiliary electrode 15 may be in a rod shape, a block shape, or the like, for example.

[0053] In the present embodiment, the auxiliary electrode 15 is in a triangular plate shape, but the auxiliary electrode 15 is not limited to the triangular plate shape, and may be in a rectangular plate shape, for example.

[0054] In the present embodiment, the auxiliary electrode 15 is mounted on the outside of the metal tube 2 serving as the first electrode and is electrically connected to the metal tube 2. The triangular plate-shaped auxiliary electrode 15 is mounted on the outside of the metal tube 2 with one side as the upper side and the vertex opposite to the one side as the lower side. Therefore, the auxiliary electrode 15 is not likely to become an obstacle for the plated object, the medium, and the insulating ball to pass through the plating forming portion 4. That is, the further the plating forming portion 4 goes from the top to the bottom, the larger the cross-sectional area of ​​the space except for the part where the auxiliary electrode 15 is located, so the plated object, the medium, and the insulating ball pass smoothly. In addition, the auxiliary electrode 15 may not be mounted on the metal tube 2, but may be independently hung down from, for example, a reflector 13.

[0055] In this embodiment, when viewed in the planar direction, the four auxiliary electrodes 15 are arranged radially around the metal pipe 2. Therefore, the auxiliary electrodes 15 can evenly supply current to the plating forming portion 4. In addition, the number of auxiliary electrodes 15 is not limited to 4, and may be less than 4 or more than 4.

[0056] In the plating apparatus 100 according to the first embodiment having the above-described structure, the auxiliary electrode 15 assists in the electrical connection between the metal pipe 2 as the first electrode and the plating forming region of the object to be plated, thereby shortening (improving) the time required to reach a desired plating thickness.

[0057] Furthermore, in the plating device 100 according to the first embodiment, since the auxiliary electrode 15 assists in the electrical connection between the metal tube 2 as the first electrode and the plating forming area of ​​the object to be plated, a uniform current can be supplied to the plating forming portion 4, thereby suppressing thickness deviation of the formed plating film.

[0058] (Usage Example of Plating Apparatus 100)

[0059] An example of a plating process using the plating apparatus 100 is described below.

[0060] First, a desired plating solution is put into the plating tank 1 .

[0061] Next, objects to be plated, dielectrics, and insulating balls of desired shapes, desired sizes, and desired numbers are introduced into the guide portion 12 in the plating tank 1. The order of introducing the plating solution and the objects to be plated, dielectrics, and insulating balls may be reversed. The introduced objects to be plated, dielectrics, and insulating balls are accumulated in the plating forming portion 4.

[0062] Next, the pump 9 is driven to eject the plating solution from the ejection port 6a of the ejection portion 6. As a result, an upward flow of the plating solution is generated inside the metal pipe 2. Then, a portion of the objects to be plated, the dielectric, and the insulating balls accumulated in the plating forming portion 4 are taken out from the lower end of the plating forming portion 4 to the mixing portion 11, mixed with the ejected plating solution, and rise inside the metal pipe 2 along with the upward flow.

[0063] The object to be plated, the dielectric, and the insulating balls rising in the metal pipe 2 are ejected outward from the upper end of the metal pipe 2 and stirred.

[0064] The stirred object to be plated, dielectric, and insulating balls are deposited on the upper side of other objects to be plated, dielectric, and insulating balls that have already been deposited on the plating forming portion 4 .

[0065] A portion of the objects to be plated, dielectrics, and insulating balls accumulated in the plating forming section 4 is taken out from the lower end of the plating forming section 4 to the mixing section 11, whereby newly accumulated objects to be plated, dielectrics, and insulating balls gradually descend. In this way, the objects to be plated, dielectrics, and insulating balls circulate inside the plating device 100.

[0066] Next, the power source 14 is driven to apply a current between the metal pipe 2 as the first electrode and the second electrode 5. As a result, plating on the object to be plated is started in the plating forming portion 4.

[0067] When a plated film of a desired thickness is formed on the object to be plated after a given period of time, the power source 14 is stopped to stop plating the object to be plated. Next, the pump 9 is stopped to stop the circulation of the object to be plated, the dielectric, and the insulating balls in the plating apparatus 100.

[0068] The plating process is completed by taking out the object to be plated, the dielectric, and the insulating ball from the plating tank 1 and sorting the object to be plated.

[0069] (Experiment 1)

[0070] In order to confirm the effectiveness of the present invention, the following Experiment 1 was performed.

[0071] The above-mentioned plating apparatus 100 was prepared for Example 1.

[0072] In addition, a plating device 1100 was prepared for Comparative Example 1. Figure 4 As shown in (A) to (C) of FIG. 1 , the plating apparatus 1100 omits the auxiliary electrode 15 attached to the metal pipe 2 of the plating apparatus 100 (the structure is set to be without the auxiliary electrode 15 ). The other structures of the plating apparatus 1100 are set to be the same as those of the plating apparatus 100 .

[0073] In addition, in both the plating apparatus 100 and the plating apparatus 1100, the length of the plating forming portion 4 is set to 220 mm.

[0074] Mixtures of a plated object, a dielectric, and an insulating ball were prepared for Example 1 and Comparative Example 1. The structure and mixing amount of the mixture for Example 1 and the mixture for Comparative Example 1 were the same.

[0075] The total amount of the plated object, dielectric, and insulating balls was 1720cc. The mixing ratio was 1376cc (80 volume %) of the plated object, 86cc (5 volume %) of the dielectric, and 258cc (15 volume %) of the insulating balls.

[0076] For Example 1 and Comparative Example 1, the same plating solution was prepared.

[0077] Example 1 The plating apparatus 100, the mixture, and the plating solution were used to perform plating on the object for 210 minutes. The magnitude of the applied current was set to 0.17 A / dm 2 The spray flow rate of the plating solution was set to 85 L / min. However, after 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, and 210 minutes from the start of plating, the plating device 1100 was stopped, 30 objects to be plated were taken out, and the thickness of the formed plated films was measured.

[0078] In Comparative Example 1, the plating apparatus 1100, the mixture, and the plating solution were used to perform plating on the object for 210 minutes. The magnitude of the applied current was set to 0.17 A / dm 2 The spray flow rate of the plating solution was set to 85 L / min. Then, similarly, after 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, and 210 minutes from the start of plating, the plating device 1100 was stopped, 30 objects to be plated were taken out, and the thickness of the formed plated films was measured.

[0079] Table 1 shows the details of Example 1 and Comparative Example 1.

[0080] [Table 1]

[0081]

[0082] exist Figure 5 (A) shows the distribution (frequency) of the thickness of the plated film formed on 30 objects to be plated 60 minutes after the start of plating in Example 1. Figure 5 (B) shows the distribution (frequency) of the thickness of the plated film formed on 30 objects to be plated in Comparative Example 1 60 minutes after the start of plating.

[0083] right Figure 5 (A) and Figure 5 As can be seen from the comparison of (B), Example 1 tends to have a larger thickness of the plating film than Comparative Example 1 as a whole.

[0084] As described above, the plating apparatus 100 can confirm that the deposition rate of the plated film is improved by attaching the auxiliary electrode 15 to the metal pipe 2 to assist the electrical connection between the metal pipe 2 and the plated formation region of the object to be plated via the auxiliary electrode 15 .

[0085] exist Figure 6 The graphs for Example 1 and Comparative Example 1 show the variation (CV (%)) in the thickness of the plated film after 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, and 210 minutes from the start of plating.

[0086] according to Figure 6 It can be seen that Example 1 has a small deviation as a whole. Example 1 has a smaller deviation than Comparative Example 1 after 60 minutes, 90 minutes, 120 minutes, and 150 minutes from the start of plating. Comparative Example 1 has a large deviation after 60 minutes from the start of plating. After 180 minutes and 210 minutes, Example 1 and Comparative Example 1 have the same degree of deviation.

[0087] In this way, the plating device 100 installs the auxiliary electrode 15 on the metal tube 2, thereby assisting the electrical connection between the metal tube 2 and the plating forming area of ​​the plated object through the auxiliary electrode 15, and can supply a uniform current to the plating forming area, so that it can be confirmed that the thickness deviation of the formed plated film is suppressed.

[0088] As described above, the present invention exhibits unique excellent effects.

[0089] [Second embodiment]

[0090] A plating apparatus 200 according to the second embodiment was produced. The plating apparatus 200 is obtained by modifying a part of the structure of the plating apparatus 100 according to the first embodiment.

[0091] Specifically, in the plating device 100, four triangular auxiliary electrodes 15 are installed on the outside of the metal pipe 2 as the first electrode. The plating device 200 is modified as follows. Figure 7 As shown, the four auxiliary electrodes 25 are removed from the metal pipe 2 so that they are suspended in the plating forming portion 4 by the conductive and rod-shaped supporting portion 25b. In addition, the shape of the auxiliary electrode 25 is changed from a triangular plate to a rectangular plate. In addition, the front end of the supporting portion 25b of the auxiliary electrode 25 is respectively attached to the lower surface of the reflector 13, for example.

[0092] The auxiliary electrode 25 is electrically connected to the metal pipe 2 as the first electrode via the support portion 25b. The auxiliary electrode 25 assists the metal pipe 2 as the first electrode and plays a role of increasing the number of power supply points.

[0093] The arrangement of the four auxiliary electrodes 25 is as follows: Figure 8 There are three types shown in (A), (B), and (C). In addition, Figure 8 (A), (B), and (C) are cross-sectional views of the main parts of the plating device 200. Figure 8 The plating apparatus 200A shown in (A) is Figure 8 The plating device 200B shown in (B) is Figure 8 The one shown in (C) is a plating device 200C. Figure 7 The plating apparatus 200 shown corresponds to the plating apparatus 200B.

[0094] In the plating apparatus 200A, four auxiliary electrodes 25 are arranged on the side of the metal pipe 2. The four auxiliary electrodes 25 are arranged radially around the metal pipe 2. The auxiliary electrodes 25 may be in contact with the metal pipe 2 or may be separated with a small gap therebetween.

[0095] In the plating apparatus 200B, four auxiliary electrodes 25 are arranged between the metal pipe 2 and the mesh pipe 3. The four auxiliary electrodes 25 are arranged radially with the metal pipe 2 as the center.

[0096] In the plating apparatus 200C, four auxiliary electrodes 25 are arranged on the side of the mesh pipe 3. The four auxiliary electrodes 25 are arranged parallel to the mesh surface of the mesh pipe 3, respectively.

[0097] (Experiment 2)

[0098] In order to compare the performances of the plating apparatus 200A, the plating apparatus 200B, and the plating apparatus 200C with each other, the following Experiment 2 was performed.

[0099] In Example 21, the plating apparatus 200A was used. In Example 22, the plating apparatus 200B was used. In Example 23, the plating apparatus 200C was used.

[0100] For Example 21, Example 22, and Example 23, the same mixture of the object to be plated, dielectric, and insulating ball as used in Experiment 1 (Example 1 and Comparative Example 1) was prepared. The mixture ratios and amounts for Example 21, Example 22, and Example 23 were the same as each other.

[0101] For Example 21, Example 22, and Example 23, the same plating solution as used in Experiment 1 was prepared.

[0102] In Examples 21, 22, and 23, the mixture and the plating solution were used to plate the object for 210 minutes. The magnitude of the applied current was set to 0.17 A / dm 2 The spray flow rate of the plating solution was set to 85 L / min. Then, similarly to Experiment 1, the plating device 200 was stopped after 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, and 210 minutes from the start of plating, and 30 objects to be plated were taken out, and the thickness of the formed plated films was measured.

[0103] The details of Example 21, Example 22, and Example 23 are shown in Table 2, respectively.

[0104] [Table 2]

[0105]

[0106] exist Fig. 9 The deviation (CV (%)) of the thickness of the plated film after 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, and 210 minutes from the start of plating is shown in Example 21, Example 22, and Example 23, respectively.

[0107] according to Fig. 9 It can be seen that the deviation of Example 21 in which the four auxiliary electrodes 25 are arranged on the side of the metal pipe 2 is small overall. Example 21 has a smaller deviation than Example 22 in which the four auxiliary electrodes 25 are arranged between the metal pipe 2 and the mesh pipe 3 and Example 23 in which the four auxiliary electrodes 25 are arranged on the side of the mesh pipe 3 after 60 minutes, 90 minutes, 120 minutes, and 150 minutes from the start of plating. In addition, Example 22 in which the four auxiliary electrodes 25 are arranged between the metal pipe 2 and the mesh pipe 3 has a smaller deviation overall than Example 23 in which the four auxiliary electrodes 25 are arranged on the side of the mesh pipe 3. Example 22 has a smaller deviation than Example 23 after 60 minutes, 90 minutes, 120 minutes, and 180 minutes from the start of plating.

[0108] As described above, when the auxiliary electrode 25 is disposed in the plating forming portion 4, it is possible to suppress the variation in the thickness of the plated film more by disposing it closer to the metal pipe 2 as the first electrode than to disposing it closer to the mesh pipe 3.

[0109] The plating apparatus 100 and the plating apparatus 200 (plating apparatuses 200A, 200B, and 200C) according to the embodiment have been described above, but the present invention is not limited to the above-described contents, and various modifications can be made in accordance with the gist of the invention.

[0110] For example, in the above-described embodiment, the number of the auxiliary electrodes 15 and 25 is set to four, respectively. However, the number of the auxiliary electrodes 15 and 25 is arbitrary, and may be less than four or more than four.

[0111] Furthermore, in the above-described embodiment, the auxiliary electrodes 15 and 25 are formed as triangular plates or rectangular plates, but the auxiliary electrodes 15 and 25 may be formed in any shape and may be formed in other shapes.

[0112] A plating apparatus according to an embodiment of the present invention is as described in the column of “Solution to Problem”.

[0113] In the plating apparatus, it is also preferable that the first electrode is a cathode electrode and the second electrode is an anode electrode.

[0114] Furthermore, it is also preferable that the auxiliary electrode is attached to the outside of the metal pipe and is electrically connected to the metal pipe. In this case, the auxiliary electrode can be easily provided.

[0115] It is also preferable that the auxiliary electrode hangs down in the plating forming portion. In this case, the auxiliary electrode can be arranged at an arbitrary position of the plating forming portion.

[0116] It is also preferable that there are a plurality of auxiliary electrodes. In this case, current can be supplied to the plating-formed portion more uniformly.

[0117] It is also preferable that the number of auxiliary electrodes is 4. In this case, current can be supplied to the plating-formed portion more uniformly.

[0118] It is also preferable that the auxiliary electrodes are arranged radially around the metal pipe when viewed in the planar direction. In this case, current can be supplied more uniformly to the plated portion.

[0119] It is also preferable that the auxiliary electrode is a metal plate. In this case, it is possible to prevent the auxiliary electrode from hindering the passage of the plated object, dielectric, insulating ball, etc. through the plating forming portion.

[0120] In this case, it is also preferred that the metal plate is a triangular plate, with one side of the triangle as the upper side and the vertex opposite to the one side as the lower side, and is arranged in the plating forming portion. In this case, it is possible to further suppress the auxiliary electrode from obstructing the plated object, dielectric, insulating ball, etc. from passing through the plating forming portion. However, the shape of the metal plate is arbitrary, for example, it can also be a rectangular plate.

[0121] Description of Reference Numerals

[0122] 1···plating tank;

[0123] 2···metal tube (first electrode; cathode);

[0124] 2a···hollow part;

[0125] 2b···supporting portion;

[0126] 3···Screen tube;

[0127] 3a···hollow part;

[0128] 4···plating forming portion;

[0129] 5···2nd electrode (anode);

[0130] 6···jet unit;

[0131] 6a···jet port;

[0132] 7···Circular line;

[0133] 8···Liquid suction port;

[0134] 9···Pump;

[0135] 10···Filter;

[0136] 11···Mixing Department;

[0137] 12···guiding department;

[0138] 13···Reflector (deflector);

[0139] 13a···Suppression plate;

[0140] 14···Power supply;

[0141] 15, 25···Auxiliary electrode;

[0142] 25a···support portion.

Claims

1. A plating device comprising: A plating tank storing the plating solution; The cylindrical metal tube is the first electrode and has a hollow portion; A cylindrical screen pipe made of an insulating material and having a hollow portion; and The second electrode, The metal tube, the mesh tube and the second electrode are respectively accommodated in the plating tank, The metal pipe is arranged in the hollow portion of the mesh pipe, and a plating forming portion is formed between the inner side of the mesh pipe and the outer side of the metal pipe. The second electrode is arranged outside the sieve tube, generating an upward flow in the hollow portion of the metal pipe to cause the plating solution to rise, The object to be plated rises in the hollow portion of the metal pipe along with the rising flow of the plating solution, is discharged to the outside of the metal pipe, is stirred, and then descends in the plating forming portion. During the descent, the object is plated by applying a current between the metal pipe serving as the first electrode and the second electrode. in, An auxiliary electrode electrically connected to the metal pipe as the first electrode is provided in the plating forming portion.

2. The plating device according to claim 1, wherein: The first electrode is a cathode electrode, The second electrode is an anode electrode.

3. The plating device according to claim 1 or 2, wherein: The auxiliary electrode is installed on the outside of the metal tube and is electrically connected to the metal tube.

4. The plating device according to claim 1 or 2, wherein: The auxiliary electrode hangs down in the plating forming portion.

5. The plating device according to any one of claims 1 to 4, wherein: There are a plurality of auxiliary electrodes.

6. The plating device according to claim 5, wherein: There are four auxiliary electrodes.

7. The plating device according to any one of claims 1 to 6, wherein: When viewed in the plane direction, The auxiliary electrodes are arranged radially around the metal tube.

8. The plating device according to any one of claims 1 to 7, wherein: The auxiliary electrode is a metal plate.

9. The plating device according to claim 8, wherein: The metal plate is a triangular plate. The metal plate is arranged in the plating forming portion with one side of the triangle being the upper side and a vertex facing the one side being the lower side.

10. The plating device according to claim 8, wherein: The metal plate is a rectangular plate.

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