Continuous metal foil plating apparatus, continuous metal foil plating method, and method for managing electrolytic solution of continuous plating apparatus

Abstract

The present invention relates to a manufacturing apparatus and a manufacturing method capable of manufacturing metal foils such as iron-nickel alloy foils, nickel foils, and copper foils with high quality through a continuous plating method. The continuous metal foil plating apparatus according to the present invention includes an electrolytic cell for accommodating an electrolytic solution, an anode disposed inside the electrolytic cell, a cathode disposed opposite the anode at a predetermined interval, and a power supply device for applying current to the anode and the cathode. An electrolytic solution is supplied to one side of the space formed between the anode and the cathode, and the electrolytic solution is discharged from the other side of the space. The height of the one side where the electrolytic solution is supplied is formed higher than the height of the other side, and the electrolytic solution flows through the space formed between the anode and the cathode due to the potential energy difference between the one side and the other side. Metal ions contained in the electrolytic solution are electrodeposited on the cathode during the process of passing through the space formed between the anode and the cathode, and a metal foil is formed.

Description

Detailed Description of the Invention

[0001] 〔Technical Field〕 The present invention relates to a continuous metal foil plating apparatus, a continuous metal foil plating method, and an electrolytic solution management method for a continuous plating apparatus. More specifically, the present invention relates to a continuous plating apparatus, a continuous plating method, and an electrolytic solution management method for use in continuous plating that can produce high-quality metal foils such as iron-nickel alloy foils, nickel foils, and copper foils through a continuous plating method.

[0002] 〔Background Art〕 Invar alloy is an alloy with a very low coefficient of thermal expansion and is a material used in various fields such as precision measuring instruments, bimetals, shadow masks, lead frames for integrated circuits, display sealing materials, and metal masks for organic light-emitting diodes.

[0003] In order to increase the resolution of OLEDs applied to smartphones, it is necessary to reduce the thickness of the fine metal mask (FMM) used in the vapor deposition process.

[0004] Such a fine metal mask is manufactured through a top-down method involving casting-rolling-etching. However, in such a top-down method, it is difficult to realize a fine metal mask having a thickness of 10 μm or less. Therefore, attempts have been made to manufacture an invar alloy foil having a thin thickness through electroforming plating and then perform etching, or to directly manufacture a fine metal mask having a pattern formed through electroforming plating.

[0005] On the other hand, since invar alloy is composed of an iron-nickel alloy, it is difficult to realize the physical properties required for a metal mask if the uniformity of the alloy composition in the plating solution is not maintained. Therefore, despite many research and developments to maintain the uniformity of the alloy composition, the invar alloy foils manufactured by electroforming plating technology to date do not meet the physical properties required for a fine metal mask.

[0006] In addition, organic components such as saccharin and thiourea are added to the inverter electrolyte for the purpose of increasing the density of the plated inverter alloy foil and controlling internal stress. Such organic components can be eutectic inside the crystal during the plating process and may also precipitate in the form of FeS or the like at the crystal boundary (especially near the triple point) during the heat treatment process. The eutectic of such impurities induces adverse effects such as increasing the coefficient of thermal expansion of the produced inverter alloy foil and increasing brittleness. Therefore, in order to improve the properties of the inverter alloy foil produced through continuous plating, an electrolyte management technology that reduces the factors inducing the coefficient of thermal expansion is required, but little technology regarding this has been developed.

[0007] 〔Summary of the Invention〕 〔Problems to be Solved by the Invention〕 The first object of the present invention is to provide a continuous metal foil plating apparatus capable of producing high-quality metal foils such as alloy foils like Fe-Ni alloys, as well as nickel foils, copper foils, etc.

[0008] The second object of the present invention is to provide a continuous metal foil plating method capable of producing high-quality metal foils such as alloy foils like Fe-Ni alloys, as well as nickel foils, copper foils, etc.

[0009] The third object of the present invention is to provide an electrolyte management method that can uniformly maintain the physical properties of the metal foil formed during continuous plating and minimize the factors that adversely affect the physical properties.

[0010] 〔Means for Solving the Problems〕 A first aspect of the present invention includes an electrolytic cell for containing an electrolytic solution, a positive electrode disposed inside the electrolytic cell, a negative electrode disposed opposite to the positive electrode at a predetermined interval, and a power supply device for applying a current to the positive electrode and the negative electrode. An electrolytic solution is supplied to one side of the space formed between the positive electrode and the negative electrode, and the electrolytic solution is discharged from the other side of the space. The height of the one side where the electrolytic solution is supplied is formed higher than the height of the other side. Due to the potential energy difference between the one side and the other side, the electrolytic solution flows through the space formed between the positive electrode and the negative electrode. During the process of passing through the space formed between the positive electrode and the negative electrode, metal ions contained in the electrolytic solution are electrodeposited on the negative electrode to form a metal foil. The present invention provides a continuous plating apparatus for manufacturing a metal foil, characterized in that.

[0011] A second aspect of the present invention is a method of supplying an electrolytic solution between a positive electrode and a negative electrode disposed opposite to the positive electrode at a predetermined interval, applying a current to the positive electrode and the negative electrode, and forming a metal foil on the surface of the negative electrode. The method includes making the height of one side of the space formed between the positive electrode and the negative electrode higher than the height of the other side, and allowing the electrolytic solution to flow through the space formed between the positive electrode and the negative electrode due to the potential energy difference between the one side and the other side, and passing through the space formed between the positive electrode and the negative electrode. The present invention provides a continuous metal foil plating method, characterized in that.

[0012] A third aspect of the present invention includes the steps of collecting an electrolytic solution from a plating bath or an electrolytic solution storage tank for supplying the electrolytic solution, adjusting the concentration of the electrolytic solution to the undiluted state or a diluted state at a predetermined ratio by selectively diluting the electrolytic solution with a diluent at a predetermined ratio, irradiating light on the electrolytic solution with the adjusted concentration to analyze the light absorption characteristics of the electrolytic solution with the adjusted concentration and analyze the composition of the electrolytic solution, and adjusting the composition of the electrolytic solution in the plating bath based on the difference between the analyzed composition of the electrolytic solution and the preset composition of the electrolytic solution. When the analysis of the light absorption characteristics is performed in the ultraviolet region, the electrolytic solution and the diluent are analyzed in a state diluted at a predetermined ratio. The present invention provides an electrolytic solution management method, characterized in that.

[0013] 〔Advantages of the Invention〕 According to the present invention, by controlling and supplying the electrolytic solution to pass between the positive electrode and the negative electrode by utilizing the potential energy difference due to the height difference between the side where the electrolytic solution is supplied and the side where it is discharged, a steady state where the amount of the electrolytic solution supplied between the positive electrode and the negative electrode is the same as the amount of the electrolytic solution discharged, or a state very close to the steady state is realized, and thus the uniformity of the composition of the electrolytic solution in contact with the cathode during the electroplating process can be greatly improved as compared with the conventional case.

[0014] Accordingly, in the case of the Fe-Ni alloy foil manufactured by the apparatus of the present invention, it is expected to satisfy the characteristics required for the fine metal mask.

[0015] In addition, when the apparatus and method according to the present invention are used for manufacturing foils of pure metals such as nickel foil and copper foil, the density of the formed foil can be further improved, and thus a metal foil having improved characteristics as compared with the metal foil manufactured by the conventional plating apparatus can be obtained.

[0016] 〔Brief Description of the Drawings〕 FIG. 1 is a perspective view of a continuous metal foil plating apparatus according to Example 1 of the present invention.

[0017] FIG. 2 is a partially exploded perspective view of a continuous metal foil plating apparatus according to Example 1 of the present invention.

[0018] FIG. 3 is a cross-sectional view of a continuous metal foil plating apparatus according to Example 1 of the present invention.

[0019] FIG. 4 is a cross-sectional view of a continuous metal foil plating apparatus according to Example 2 of the present invention.

[0020] FIG. 5 is a schematic view of a continuous metal foil plating apparatus according to Example 3 of the present invention.

[0021] FIG. 6 is a schematic view of a continuous metal foil plating apparatus according to Example 4 of the present invention.

[0022] FIG. 7 shows the ultraviolet-visible spectrum results measured while diluting an iron-nickel electrolytic solution with ultrapure water.

[0023] Figure 8(a) shows the ultraviolet-visible spectrum results measured while diluting a 97 g / L NiSO4 solution with ultrapure water, and Figure 8(b) shows the ultraviolet-visible spectrum results measured while diluting an 85 g / L FeSO4 solution with ultrapure water.

[0024] Figure 9(a) shows the ultraviolet-visible spectrum results measured while diluting an 85 g / L FeSO4 solution with ultrapure water after exposing it to air for 24 hours, and Figure 9(b) shows the ultraviolet-visible spectrum results measured while diluting the solution with ultrapure water after exposing an 85 g / L FeSO4 solution to air for 24 hours and removing the precipitate.

[0025] Figure 10(a) shows the ultraviolet-visible spectrum results measured while diluting a 2 g / L ascorbic acid solution with ultrapure water, and Figure 10(b) shows the ultraviolet-visible spectrum results measured while diluting a 2.6 g / L saccharin solution with ultrapure water.

[0026] Figure 11 shows the ultraviolet-visible spectrum of a standard plating solution (97 g / L Ni, 85 g / L FeSO4, 2.6 g / L saccharin, 1.0 g / L ascorbic acid, 25 g / L boric acid, 0.2 g / L lauryl) analyzed using a short optical path cell (transmission length: 0.1 mm), and the ultraviolet-visible spectrum analyzed using a general cell (transmission length: 10 mm) after diluting the plating solution by 1 / 100.

[0027] Figure 12 shows the ultraviolet-visible spectrum results of 30 g / L NaCl, 0.2 g / L sodium laurylsulfate (hereinafter referred to as "lauryl"), and 25 g / L boric acid.

[0028] Figure 13(a) shows the ultraviolet-visible spectrum results when NiSO4 and multiple additives are mixed, and Figure 13(b) shows the ultraviolet-visible spectrum results when FeSO4 and multiple additives are mixed.

[0029] Figure 14(a) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid and diluting it 1 / 200 with ultrapure water, and Figure 14(b) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid in the undiluted state. 3+ Figure 14(a) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid and diluting it 1 / 200 with ultrapure water, and Figure 14(b) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid in the undiluted state. 3+ Figure 14(a) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid and diluting it 1 / 200 with ultrapure water, and Figure 14(b) shows the ultraviolet-visible spectrum results obtained by adding a certain amount of Fe to 1.0 g / L of ascorbic acid in the undiluted state.

[0030] Figure 15 is a schematic diagram of the plating solution analysis process according to an embodiment of the present invention.

[0031] Figure 16 shows a training set and a validation set for the partial least squares regression analysis algorithm.

[0032] Figure 17 shows the ultraviolet-visible spectrum results obtained through each of the solutions shown in Figure 16, where dilution was performed 1 / 200 in the 200 - 500 nm region and analysis was performed in the undiluted state in the 500 - 1000 nm region.

[0033] Figure 18 shows the calibration results derived through partial least squares regression analysis using the data of Figures 16 and 17.

[0034] 〔Best Mode for Carrying Out the Invention〕 Hereinafter, the configuration and operation of the embodiments of the present invention will be described with reference to the accompanying drawings.

[0035] In the description of the present invention, when it is determined that a specific description of related known functions or configurations obscures the gist of the present invention unnecessarily, the detailed description thereof is omitted. Further, when a certain part describes a certain component as "including", this does not exclude other components unless otherwise stated to the contrary, and means that other components may be further included.

[0036] In the present invention, the "steady state" means a state in which the amount of the electrolytic solution flowing into the space between the positive electrode and the negative electrode is the same as the amount of the electrolytic solution discharged from the space between the positive electrode and the negative electrode.

[0037] <First Embodiment> The first embodiment of the present invention includes an electrolytic cell for storing an electrolytic solution, a positive electrode disposed inside the electrolytic cell, a negative electrode disposed opposite to the positive electrode at a predetermined interval, and a power supply device for applying a current to the positive electrode and the negative electrode. An electrolytic solution is supplied to one side of the space formed between the positive electrode and the negative electrode, and the electrolytic solution is discharged to the other side of the space. The height of the one side where the electrolytic solution is supplied is formed higher than the height of the other side, and the electrolytic solution flows through the space formed between the positive electrode and the negative electrode due to the potential energy difference between the one side and the other side. Metal ions contained in the electrolytic solution are electrodeposited on the negative electrode during the process of passing through the space formed between the positive electrode and the negative electrode to form a metal foil. It is a continuous metal foil electroplating apparatus characterized by this.

[0038] Thus, when the electrolytic solution is caused to flow by utilizing the potential energy difference at the location where the electrolytic solution is supplied and discharged, it is advantageous to maintain the electrolytic solution in a steady-state or a state very close to the steady-state within the space between the positive electrode and the negative electrode. Therefore, not only can the composition of the electrolytic solution between the positive electrode and the negative electrode where electroplating is performed be kept constant, but also the generation of bubbles and vortices during the process of flowing the electrolytic solution can be reduced, and a metal foil with excellent uniformity can be obtained. As a result, in the case of alloy plating, the composition uniformity can be enhanced over the entire metal foil, and in the case of single-metal plating, the density can be enhanced.

[0039] The electrolyte level (H in ) on the electrolyte supply side and the electrolyte level (H out ) on the electrolyte discharge side, the difference (H in - H out ), is not particularly limited as long as the electrolyte can flow due to the potential energy. For example, the difference (H in - H out ) can be set to be greater than 0 or equal to or greater than the distance between the positive electrode and the negative electrode. Further, the difference (H in - H out ) can be adjusted in various ways according to the required flow rate of the electrolyte. For example, when increasing the flow rate, the height difference can be increased, and when decreasing the flow rate, the height difference can be decreased.

[0040] In the first embodiment, the electrolyte guide means can be further included, which is disposed on the electrolyte injection side of the positive electrode and guides the electrolyte to be supplied to the space formed between the positive electrode and the negative electrode at a predetermined angle and speed.

[0041] The electrolyte guide means can be advantageous for realizing a steady state or a state very close to the steady state of the electrolyte supplied between the positive electrode and the negative electrode by assisting the electrolyte to enter between the positive electrode and the negative electrode at a predetermined angle and speed while maintaining laminar flow.

[0042] In the first embodiment, an electrolyte storage tank can be further included to collect the electrolyte discharged through the space formed between the positive electrode and the negative electrode and to process the collected electrolyte. The processing of the electrolyte includes removing impurities generated from the electrodeposition process or adding necessary components to maintain the composition of the electrolyte in its initial state.

[0043] In the first embodiment, the electrolyte supplied through the electrolyte storage tank can be supplied to the lower part on one side of the electrolyte guide means, fill the upper part of the electrolyte guide means, and then be supplied to the space between the positive electrode and the negative electrode.

[0044] In the first embodiment, various electrolytes for forming metal foils such as an electrolyte for forming an Fe-Ni alloy foil, an electrolyte for forming a nickel foil, and an electrolyte for forming a copper foil can be used. For example, in the case of the electrolyte for forming an Fe-Ni alloy foil, iron sulfate hydrate (Iron Sulfate, FeSO4, 7H2O), nickel sulfate hexahydrate (Nickel sulfate hexahydrate, NiSO4, 6H2O), boric acid (Boric acid, H3BO3), sodium saccharine (Sodium saccharine, C7H4NO3SNa), sodium lauryl sulfate (Sodium Lauryl Sulfate, Cl2H 25 O4SNa), and sodium chloride (NaCl) can be included. More specifically, the electrolyte can include 0.49 to 0.94 parts by weight of nickel sulfate hexahydrate, 0.20 to 0.31 parts by weight of boric acid, 0.009 to 0.044 parts by weight of sodium saccharine, 0.0009 to 0.0033 parts by weight of sodium lauryl sulfate, and 0.23 to 0.37 parts by weight of sodium chloride with respect to 1 part by weight of iron sulfate hydrate.

[0045] In the first embodiment, the positive electrode can be formed of a downwardly concave arc-shaped plate, and the positive electrode material can be used without special restrictions as long as it has characteristics that can be used in a positive electrode. Also, the shape of the positive electrode can be variously adjusted according to the shape of the opposing negative electrode.

[0046] In the first embodiment, the negative electrode can be formed in the shape of a drum with a circular cross-section.

[0047] In the first embodiment, the drum-shaped negative electrode is made of a clad metal having two or more layers. The surface layer is made of a first metal such as titanium, a titanium alloy, or stainless steel, and the inner layer can be made of copper (Cu), silver (Ag), aluminum (Al), or an alloy thereof (copper alloy, silver alloy, aluminum alloy) with excellent electrical conductivity. The clad metal can be manufactured by various methods such as welding two thin plates, joining using a bonding material, plating, or coating.

[0048] In the first embodiment, unevenness (or a pattern) for forming the surface roughness of the metal foil formed on the negative electrode within a predetermined value range may be formed on the surface of the negative electrode.

[0049] In the first embodiment, the electrolytic solution guiding means may have a flat shape or a bent shape inclined at a predetermined angle, and the entry angle of the electrolytic solution supplied to the space formed between the positive electrode and the negative electrode can be adjusted by adjusting the shape (inclined angle or curvature) of the electrolytic solution guiding portion.

[0050] In the first embodiment, an auxiliary guide (cover) for leveling the height of the electrolytic solution may be disposed above the electrolytic solution guiding means.

[0051] By means of such an auxiliary guide (cover), the height of the electrolytic solution can be kept constant for the entire drum-shaped negative electrode.

[0052] The entry angle of the electrolytic solution can be adjusted in various ways. For example, it can be made substantially the same as the curvature of the positive electrode and the negative electrode.

[0053] In the first embodiment, the shape of the location where the electrolytic solution is discharged may be such that the electrolytic solution is discharged directly into the electrolytic solution storage tank as soon as it passes between the positive electrode and the negative electrode facing each other, or after passing through a discharge guide such as a flat shape, a concave shape, or a convex shape and then discharged into the electrolytic solution storage tank.

[0054] In the first embodiment, means for suppressing the generation of vortices in the electrolytic solution may be provided to suppress the generation of bubbles in the process of discharging the electrolytic solution into the electrolytic solution storage tank.

[0055] In the first embodiment, the surface of the negative electrode may be formed with a predetermined pattern composed of a region where electrodeposition is performed and a region where electrodeposition is not performed. Through the negative electrode formed with such a pattern, the pattern of the negative electrode is transferred to the metal foil formed, and it can be immediately formed into a shape such as a metal mesh or a fine metal mask.

[0056] <Second Embodiment> The second embodiment of the present invention is a method of supplying an electrolytic solution between a positive electrode and a negative electrode disposed opposite to the positive electrode at a predetermined interval, applying a current to the positive electrode and the negative electrode so that a metal foil is formed on the surface of the negative electrode, wherein the height of one side of the space formed between the positive electrode and the negative electrode is made higher than the height of the other side, and the electrolytic solution flows through the space formed between the positive electrode and the cathode due to the potential energy difference between the one side and the other side and passes through the space formed between the positive electrode and the negative electrode, and a metal foil is formed on the surface of the negative electrode.

[0057] <Third Embodiment> The third embodiment of the present invention includes the steps of collecting an electrolytic solution from a plating bath or an electrolytic solution storage tank that supplies the electrolytic solution, adjusting the concentration of the electrolytic solution to a stock solution state or a diluted state at a predetermined ratio by selectively diluting the electrolytic solution with a diluent at a predetermined ratio, irradiating the electrolytic solution with the adjusted concentration with light to analyze the absorption characteristics of the electrolytic solution with the adjusted concentration to analyze the composition of the electrolytic solution, and adjusting the composition of the electrolytic solution in the plating bath based on the difference between the analyzed composition of the electrolytic solution and a preset composition of the electrolytic solution. When the analysis of the absorption characteristics is performed in the ultraviolet region, the electrolytic solution and the diluent are analyzed in a state diluted at a predetermined ratio.

[0058] The electrolytic solution analysis method of the present invention improves the accuracy of analysis by performing the analysis in a state where the electrolytic solution is diluted with a diluent at a predetermined ratio without analyzing the electrolytic solution in a stock solution state when analyzing the components of the electrolytic solution using ultraviolet light.

[0059] In the third embodiment, the diluent preferably contains water (H2O) and has no absorbance in the wavelength range of 200 to 500 nm. The dilution ratio of the electrolytic solution to the diluent may be 1 / 2 to 1 / 400. Here, the fact that there is no absorbance in the wavelength range of 200 to 500 nm means that not only is there no complete absorbance, but also absorbance occurs at a noise level that does not affect the analysis.

[0060] This is because when the dilution ratio of the electrolytic solution is less than 1 / 2 or more than 1 / 400, it is difficult to improve the analysis accuracy of the absorbance characteristics of the components detected in the ultraviolet region. Here, a dilution ratio of 1 / 2 means mixing a diluent corresponding to twice the volume of the electrolytic solution, and 1 / 400 means mixing a diluent corresponding to 400 times the volume of the electrolytic solution. More preferably, the dilution ratio of the electrolytic solution may be 1 / 50 to 1 / 200.

[0061] In the third embodiment, when analyzing the absorbance characteristics in the wavelength range of 300 to 1000 nm, the electrolytic solution can be analyzed in its undiluted state without dilution.

[0062] When performing analysis on the visible light region or the wavelength range of 300 to 1000 nm close to it, analyzing the electrolytic solution in its undiluted state rather than in a diluted state can improve the analysis accuracy.

[0063] In the third embodiment, the spectroscopic analysis stage can include a first spectroscopic analysis stage for analyzing the wavelength range of 10 to 500 nm and a second spectroscopic analysis stage for analyzing the wavelength range of 300 to 1000 nm.

[0064] Through such ultraviolet-visible spectroscopy, it becomes possible to analyze various components contained in the iron-nickel electrolytic solution.

[0065] In the third embodiment, the electrolytic solution may contain Fe 2+ , Ni 2+ and saccharin.

[0066] In the third embodiment, the analysis of the composition of the electrolytic solution can include a step of processing the data obtained by analyzing the absorption characteristics through multivariate calibration.

[0067] Through multivariate calibration, in particular, various metal ions and organic components contained in the iron-nickel electrolytic solution can be analyzed quickly and reliably.

[0068] The multivariate calibration can be performed, for example, through a partial least square (PLS) algorithm.

[0069] Reliable analysis results can be obtained for various components contained in the iron-nickel electrolytic solution through the partial least square (PLS) algorithm.

[0070] In the third embodiment, the partial least square algorithm may be optimized to analyze Ni 2+ , Fe 2+ , Fe 3+ , stress reliever, antioxidant or iron ion precipitate that may be contained in the iron-nickel electrolytic solution, but the present invention is not limited to the exemplified components.

[0071] In the third embodiment, the stress reliever may contain saccharin, and the antioxidant may contain ascorbic acid, but the present invention is not limited to the analysis of electrolytic solutions containing the exemplified stress reliever or antioxidant.

[0072] In the third embodiment, the wavelength of the light may be 10 nm to 1000 nm.

[0073] Through this, it becomes possible to analyze the ultraviolet-visible-near infrared region, and analysis can be performed on various components contained in the electrolytic solution.

[0074] <Example 1> FIG. 1 is a perspective view of a continuous metal foil plating apparatus according to Embodiment 1 of the present invention, FIG. 2 is a partially exploded perspective view of the continuous metal foil plating apparatus according to Embodiment 1 of the present invention, and FIG. 3 is a cross-sectional view of the continuous metal foil plating apparatus according to Embodiment 1 of the present invention.

[0075] Referring to FIGS. 1 to 3, the continuous metal foil plating apparatus according to Embodiment 1 of the present invention mainly includes a plating tank 100, an electrolytic solution guiding means 200 disposed inside the plating tank 100, a positive electrode 300 coupled to one side of the upper surface of the electrolytic solution guiding means 200, a negative electrode 400 disposed at a predetermined interval from the positive electrode 300, and an electrolytic solution storage tank 500 disposed at the lower part of the plating tank 100.

[0076] The plating tank 100 is composed of a container that forms a space inside. In the embodiment of the present invention, it does not have a cover for covering the upper part, but it may be provided with a cover for covering the upper part. Also, the space is generally in a substantially rectangular shape, but it is not limited by this shape and may be in various shapes such as a rectangular shape, a circular shape, or an elliptical shape.

[0077] As shown in FIG. 2, the electrolytic solution guiding means 200 includes a positive electrode attachment part 210 that is concave downward and to which the positive electrode is attached, and an electrolytic solution guiding part 220 that guides the electrolytic solution supplied from the electrolytic solution storage tank 500 to enter the space between the positive electrode 300 and the negative electrode 400 at a controlled angle and speed.

[0078] The positive electrode attachment part 210 is formed in a concave shape downward so as to correspond to the shape of the positive electrode.

[0079] The electrolytic solution guiding part 220 has a gently convex shape upward. In the embodiment of the present invention, the electrolytic solution guiding part 220 is formed in a gently convex shape, but it may be in various shapes such as an inclined planar shape. Also, the installation angle of the electrolytic solution guiding part 220, as shown on the upper side of FIG. 3, affects the entry angle and speed of the electrolytic solution and can be adjusted and installed at various angles (such as θ1, θ2, θ3, θ4, etc.) according to the plating conditions.

[0080] At the left end of the positive electrode attachment portion 210 on the drawing surface, since it is open, the electrolytic solution that has passed between the positive electrode and the negative electrode is formed so as to be immediately discharged downward.

[0081] The maximum height of the electrolytic solution guide portion 220 is the height of the position where the electrolytic solution is supplied, and is formed higher than the height of the position where the electrolytic solution is discharged. Thereby, when a difference occurs between the potential energy of the position where the electrolytic solution is supplied to the electrolytic solution guide portion 220 and the potential energy of the position where the electrolytic solution is discharged, and the electrolytic solution is supplied to the upper part of the electrolytic solution guide portion 220, the electrolytic solution can flow to the position where it is discharged by its own weight without an externally applied force.

[0082] Further, the electrolytic solution guide means 200 forms a partition wall 230 that separates the space (first space) where the electrolytic solution is supplied and the space (second space) where the electrolytic solution is discharged in the plating tank 100, so that the supplied electrolytic solution and the discharged electrolytic solution are not mixed with each other.

[0083] The electrolytic solution that has fallen from the position where the electrolytic solution is discharged is recovered in the electrolytic solution storage tank 500 through the inlet 510 of the electrolytic solution storage tank 500 in the second space, and the electrolytic solution discharged through the outlet 520 is supplied to the first space.

[0084] The positive electrode 300 can be formed of a plate shape with a substantially arc-shaped cross section, but is not necessarily limited to a plate shape, and is not particularly limited as long as it has a facing surface that maintains a predetermined interval from the negative electrode 400.

[0085] For example, it can be formed in a shape in which the positive electrode 300 itself is supported in the plating tank 100 without adhering to the electrolytic solution guide means 200.

[0086] The negative electrode 400 has a roll shape that extends a predetermined length in the length direction for continuous plating. A rotating shaft 410 is formed on the negative electrode 400 and is rotationally driven by a driving means (not shown).

[0087] The negative electrode may be formed of a material in which copper and titanium with excellent electrical conductivity are clad. Such a cladding material is suitable for forming a uniform current density across the entire negative electrode by allowing the current applied from the outside to be rapidly transmitted to the entire negative electrode through the copper.

[0088] The distance between the positive electrode 300 and the negative electrode 400 is preferably maintained at the same distance throughout so that the electrolytic solution can easily maintain a steady state. Depending on the need for controlling the composition of the electrolytic solution and the composition of the formed foil, etc., the distance between the positive electrode 300 and the negative electrode 400 may be changed to gradually increase or decrease from the supply side to the discharge side of the electrolytic solution.

[0089] The electrolytic solution storage tank 500 is located below the plating tank 100 and recovers the electrolytic solution used in the electrodeposition process through an electrolytic solution recovery port 120 connected to the second space S2 of the plating tank 100, and supplies the treated electrolytic solution to the first space S1 through an electrolytic solution supply port 110 connected to the first space S1 of the plating tank 100.

[0090] On the other hand, in Example 1 of the present invention, the electrolytic solution storage tank 500 is installed below the plating tank 100, but it can be installed in various positions such as in parallel with the plating tank 100 or above the plating tank 100.

[0091] Also, the electrolytic solution may be processed through the electrolytic solution storage tank 500 and not supplied to the plating tank 100, and the electrolytic solution recovery tank and the electrolytic solution supply tank may be separately separated and used. In this case, the electrolytic solution recovered in the electrolytic solution recovery tank can be supplied to the electrolytic solution supply tank after undergoing processing processes such as removal of impurities and composition control.

[0092] Using the metal foil continuous plating apparatus 10 as described above, the manufacturing of the metal foil can be carried out as follows.

[0093] Referring to FIG. 3, the electrolytic solution stored in the electrolytic solution storage tank 500 is supplied to the lower part of the first space S1 through the electrolytic solution supply port 110. When the electrolytic solution is supplied and the first space S1 is filled with the electrolytic solution and the level of the electrolytic solution exceeds the upper end of the electrolytic solution guide portion 220, it will flow down by its own weight into the space between the positive electrode 300 and the negative electrode 400, and the electrolytic solution that has flowed down will pass through the space between the positive electrode 300 and the negative electrode 400 and be discharged into the second space S2.

[0094] Then, when the amount of the electrolytic solution supplied to and discharged from the space between the positive electrode 300 and the negative electrode 400 reaches a steady state or a state very close to the steady state, the negative electrode 400 is rotationally driven to apply a power supply so that electrodeposition is performed on the negative electrode 400. Of course, the negative electrode 400 may be rotationally driven simultaneously with the supply of the electrolytic solution or before reaching the steady state.

[0095] <Example 2> FIG. 4 is a cross-sectional view of the metal foil continuous plating apparatus according to Example 2 of the present invention.

[0096] The metal foil continuous plating apparatus according to Example 2 forms an electrolytic solution discharge guide portion 240 that bends and extends outside the negative electrode in the same way as the electrolytic solution supply portion side on the electrolytic solution discharge portion side, so that the discharged electrolytic solution can be smoothly discharged, which is a structure advantageous for maintaining laminar flow (or steady state) on the discharge side.

[0097] <Example 3> FIG. 5 is a schematic circuit diagram of the metal foil continuous plating apparatus according to Example 3 of the present invention.

[0098] The metal foil continuous plating apparatus according to Example 3 is an example of an apparatus that arranges the metal foil continuous plating apparatuses according to Example 1 in parallel for plating. In Example 3, two metal foil continuous plating apparatuses are arranged, but three or more apparatuses may be arranged and used if necessary.

[0099] The continuous metal foil electroplating apparatus according to Example 3 shows a process in which the foil electroplated from the first continuous metal foil electroplating apparatus 10 is peeled off and then continuously fed into the second continuous metal foil electroplating apparatus (10') to perform two-layer electroplating.

[0100] The continuous metal foil electroplating apparatus according to Example 3 is a method of electroplating through the second continuous metal foil electroplating apparatus 10' when the thickness of the metal foil formed by the first continuous metal foil electroplating apparatus 10 is thin, partial additional electroplating is required, or different metal electroplating is required. When partial additional electroplating is required, the surface of the negative electrode constituting the second continuous metal foil electroplating apparatus 10' may be divided into a region where electroplating is performed and a region where electroplating is not performed.

[0101] In addition, since the plating baths of the first continuous metal foil electroplating apparatus 10 and the second continuous metal foil electroplating apparatus 10' are separated, the compositions of the electrolytes used can be different. In this case, it is also possible to manufacture metal foils with different compositions in the thickness direction.

[0102] <Example 4> FIG. 6 is a schematic diagram of the continuous metal foil electroplating apparatus according to Example 4 of the present invention.

[0103] The continuous metal foil electroplating apparatus according to Example 4 has a structure in which two continuous metal foil electroplating apparatuses are arranged in one plating bath in the continuous metal foil electroplating apparatus according to Example 3. If necessary, three or more continuous metal foil electroplating apparatuses may be arranged in one plating bath.

[0104] <Example 5> Example 5 relates to a method for managing the electrolyte used in the above-described continuous metal foil electroplating apparatus.

[0105] Spectrum analysis was performed on the Fe-Ni electrolyte using a light source with a wavelength of 200 to 1000 nm. At this time, the ultraviolet-visible light analysis was performed in the scan mode at room temperature, and the scan speed was 10 nm / s.

[0106] Referring to Fig. 7, peaks for light absorption were observed between 200 and 300 nm, near 400 nm, near 650 nm, near 725 nm, and near 1000 nm. Among these, the light absorption peak observed between 200 and 300 nm was observed in the form of noise exceeding the detection limit, but it was confirmed that it changes to the form of a normal peak while the dilution ratio of the electrolyte solution increases.

[0107] Referring to Fig. 8(a), characteristic peaks of Ni 2+ ions were observed near 400 nm, near 650 nm, near 725 nm, and near 1000 nm. Referring to Fig. 8(b), characteristic peaks of Fe 2+ ions were observed near 900 nm. The peak observed between 200 and 300 nm in Fig. 8(b) is judged to be the characteristic peak of Fe 3+ contained as an impurity in FeSO4.

[0108] Referring to Fig. 9(a), the peak of Fe 2+ ions changes depending on the exposure time in air, which is judged to be due to the oxidation of Fe 2+ ions and the formation of precipitates. Referring to the spectra before and after the removal of the precipitate in Fig. 9(b), characteristic peaks for Fe 3+ were observed near 325 nm, and light absorption due to the precipitate was widely observed between 200 and 1000 nm. 3+

[0109] Referring to Fig. 10(a) and Fig. 10(b), light absorption was observed in the 200 - 300 nm region when saccharin and ascorbic acid were contained. At this time, since the intensity of the light absorption was strong, when analyzing in the undiluted state, peaks in the form of noise exceeding the detection limit were observed. However, when the solution containing saccharin and ascorbic acid was diluted 1 / 10, a normal peak form was observed. For saccharin, characteristic peaks were observed in the 200 - 300 nm region, and for ascorbic acid, characteristic peaks were observed near 270 nm.

[0110] ​Figure 11 shows the ultraviolet-visible spectrum of a standard plating solution (97 g / L Ni, 85 g / L FeSO4, 2.6 g / L saccharin, 1.0 g / L ascorbic acid, 25 g / L boric acid, 0.2 g / L lauryl) analyzed using a short optical path cell (transmission length: 0.1 mm). The ultraviolet-visible spectrum results analyzed using a general cell (transmission length: 10 mm) after diluting the plating solution 1 / 100 are also shown together. Peaks of saccharin and ascorbic acid were observed in the ultraviolet region both when using the short optical path cell and when diluting the plating solution. In both cases, the peak magnitude and shape of saccharin were similar, but there were differences in the peak magnitude and position of ascorbic acid. Through this, it can be seen that analyzing the diluted plating solution is advantageous for component analysis because peaks with higher sensitivity can be obtained compared to using a short optical path cell.

[0111] Also, when analyzing by dilution, it is possible to mitigate the matrix effect. Generally, when using a plating solution, side reactions such as hydrogen generation reactions occur, so a pH change is accompanied. Therefore, for the analysis of substances such as ascorbic acid that exhibit pH dependence, prior adjustment of the pH of the analysis solution is required. However, when analyzing by dilution, accurate analysis results can be obtained while omitting such a process.

[0112] Referring to Figure 12, in the case of an electrolyte solution containing NaCl, boric acid, and lauryl, no characteristic peaks were observed in the 200 - 1000 nm region.

[0113] Figure 13(a) shows the ultraviolet-visible spectrum analyzed while adding NaCl, boric acid, lauryl, etc. to a solution containing 97 g / L NiSO4. As shown in Figure 13(a), the characteristic peak regarding NiSO4 was clearly observed, but no change in the characteristic peak due to the addition of NaCl, boric acid, lauryl, etc. was observed. This is because Ni in the solution 2+It means that the ion has no interaction with NaCl, boric acid, lauryl, etc.

[0114] Figure 13(b) is the ultraviolet-visible spectrum analyzed while adding NaCl, boric acid, lauryl, etc. to the solution containing 85 g / L of FeSO4. Similar to Figure 13(a), the characteristic peak regarding FeSO4 was clearly observed, but no change in the characteristic peak due to the addition of NaCl, boric acid, lauryl, etc. was observed. This means that 2+ the Fe ion also has no interaction with NaCl, boric acid, lauryl, etc.

[0115] Figure 14 shows the ultraviolet-visible spectrum results obtained by adding Fe 3+ to the solution containing ascorbic acid. The peak of ascorbic acid observed near 270 nm gradually decreased as Fe 3+ was added. No additional absorbance due to Fe 3+ was observed, and an increase in the peak estimated to be due to Fe 2+ was observed. When the molecular ratio of ascorbic acid to Fe 3+ became 1:2, all the peaks of ascorbic acid disappeared, and the peak due to Fe 3+ began to be observed. When it became 1:2.5, the Fe 3+ peak became clear. This indicates that ascorbic acid and Fe 3+ reacted at a ratio of 1:2, ascorbic acid was oxidized, and Fe 3+ was reduced to Fe 2+ .

[0116] Through the analysis results of the absorbance characteristics of the solution as described above, Ni 2+ , Fe 2+ , Fe 3+ , Fe precipitate, saccharin, ascorbic acid, etc. in the electrolyte show absorbance characteristics in the analysis of the wavelength range of 200 - 1000 nm, while NaCl, boric acid, lauryl, etc. not only do not show absorbance characteristics, but it can also be seen that there is substantially no interaction with Ni 2+ , Fe 2+ ions.

[0117] Also, Ni 2+ , Fe 2+ , Fe 3+ , Fe precipitates, etc. have distinct light absorption characteristics in the visible light region of 300 to 1000 nm (including a part of near-infrared light). The organic substances, saccharin and ascorbic acid, have distinct light absorption characteristics in the ultraviolet region of 200 to 300 nm. However, the characteristic peaks are clearly observed in the diluted state at a predetermined ratio (for example, 1 / 200).

[0118] Fe 3+ rapidly reacts with ascorbic acid and is reduced to Fe 2+ , and the reaction ratio was ascorbic acid:Fe 3+ = 1:2.

[0119] Hydrogen ions did not have a separate peak, but the pH change could change the peak intensity of ascorbic acid. At this time, the peak intensity of ascorbic acid was greater when analyzed after dilution than when using a short optical path cell.

[0120] Then, for the analysis of the iron-nickel electrolytic solution, it is preferable to analyze the undiluted solution in the visible light region and the diluted solution in the ultraviolet region. Therefore, it can be seen that it is preferable to analyze the undiluted solution and the diluted solution concurrently during the ultraviolet-visible light analysis.

[0121] Also, since peak overlap occurs from each substance, it can be seen that it is preferable to use a multivariate analysis algorithm during analysis. The chemical species that affect the spectrum are Fe 2+ , Fe 3+ , Ni 2+ , saccharin, ascorbic acid, hydrogen ions, precipitates, etc. Among them, those for which calibration with high accuracy is possible are Fe 2+ , Fe 3+ , Ni 2+ , saccharin, and ascorbic acid.

[0122] Next, five substances with light absorption characteristics (Fe 2+ , Fe 3+, Ni 2+ , multivariate calibration was performed through the partial least square (PLS) algorithm for the analysis of ascorbic acid and saccharin.

[0123] Figure 15 is a diagram showing the data collection process for partial least squares regression analysis. For the analysis, the plating solution in its original liquid state was collected, and a part of it was diluted 1 / 200 with ultrapure water. The absorbance in the wavelength range of 200 - 500 nm for the diluted plating solution was analyzed, and for the original solution, the absorbance in the wavelength range of 500 - 1000 nm was analyzed, and these were integrated to form one spectrum. Multivariate calibration was performed through the partial least squares method between the components of the initial plating solution and its spectrum, and the evaluation of their accuracy was carried out.

[0124] Figure 16 is a diagram showing the training set and validation set for the partial least squares regression analysis algorithm. In the training set and validation set, the concentrations of Fe 3+ and ascorbic acid were adjusted considering both reactions.

[0125] As shown in Figure 17, ultraviolet - visible spectroscopy was performed for each training set. For the ultraviolet region, the spectra of the electrolyte dilution solution diluted 1 / 200 were concatenated, and for the visible light region, the spectra of the original electrolyte solution were concatenated and determined as the X - axis factor.

[0126] The analysis was performed using R software and the built - in PLS algorithm. The verification used the cross - validation method, and no separate data pre - processing was carried out.

[0127] After training, the value of the linear variable (LV) that minimizes the linear coefficient was determined, and the analysis results of the training set and validation set measured with the corresponding LV are shown in FIG. 18. As can be confirmed from FIG. 18, high accuracy can be confirmed by showing that the determined value is very close to the actual concentration.

[0128] 〔Explanation of symbols〕 10: Continuous metal foil plating apparatus 100: Plating bath 200: Electrolyte guiding means 300: Anode 400: Cathode 500: Electrolyte storage tank

Brief description of the drawings

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Claims

1. An electrolytic cell for containing an electrolytic solution, A positive electrode disposed inside the electrolytic cell, A negative electrode disposed opposite to the positive electrode at a predetermined interval, A power supply device for applying a current to the positive electrode and the negative electrode, and The electrolytic solution is supplied to one side of the space formed between the positive electrode and the negative electrode and discharged from the other side of the space, The height of the one side where the electrolytic solution is supplied is formed higher than the height of the other side, and the electrolytic solution flows through the space formed between the positive electrode and the negative electrode due to the potential energy difference between the one side and the other side. A metal foil continuous plating apparatus, characterized in that metal ions contained in the electrolytic solution are electrodeposited on the negative electrode to form a metal foil during the process of passing through the space formed between the positive electrode and the negative electrode.

2. The metal foil continuous plating apparatus according to claim 1, further comprising an electrolytic solution guiding means disposed so as to be in contact with one side of the positive electrode and guiding the electrolytic solution to be supplied to the space formed between the positive electrode and the negative electrode at a predetermined angle and speed.

3. The metal foil continuous plating apparatus according to claim 1, further comprising an electrolytic solution storage tank for collecting the electrolytic solution discharged through the space formed between the positive electrode and the negative electrode and treating the collected electrolytic solution.

4. The electrolytic solution supplied through the electrolytic solution storage tank is supplied to the lower part of one side of the electrolytic solution guiding means, filled to the upper part of the electrolytic solution guiding means, and supplied to the space between the positive electrode and the negative electrode. The metal foil continuous plating apparatus according to claim 1, characterized in that.

5. The electrolytic solution is an electrolytic solution for forming an iron-nickel alloy foil, an electrolytic solution for forming a nickel foil, or an electrolytic solution for forming a copper foil. The metal foil continuous plating apparatus according to claim 1, characterized in that.

6. The positive electrode is formed of a downwardly concave arc-shaped plate, The negative electrode has a drum shape with a non-circular cross section. The metal foil continuous plating apparatus according to claim 1, characterized in that.

7. The electrolytic solution guiding means may have a flat shape inclined at a predetermined angle or a convex shape having a predetermined curvature, and the entry angle of the electrolytic solution supplied to the space formed between the positive electrode and the negative electrode through the electrolytic solution guiding portion is adjusted. The metal foil continuous plating apparatus according to claim 1, characterized in that.

8. The metal foil continuous plating apparatus according to claim 1, further comprising an auxiliary guide for leveling the water surface height of the electrolytic solution above the electrolytic solution guiding means.

9. Including a first metal foil continuous plating apparatus and a second metal foil continuous plating apparatus according to claim 1, A metal foil continuous plating apparatus, characterized in that a first metal foil produced by the first metal foil continuous plating apparatus is introduced into the second metal foil continuous plating apparatus and plated through the second metal foil continuous plating apparatus on the first metal foil to form a second metal foil.

10. A method of supplying an electrolytic solution between a positive electrode and a negative electrode disposed opposite to the positive electrode at a predetermined interval, applying a current to the positive electrode and the negative electrode, and forming a metal foil on the surface of the negative electrode, A method for producing a metal foil, characterized in that the height of one side of the space formed between the positive electrode and the negative electrode is made higher than the height of the other side, and the electrolytic solution flows through the space formed between the positive electrode and the negative electrode due to the potential energy difference between the one side and the other side, and a metal foil is formed on the surface of the cathode when passing through the space formed between the positive electrode and the negative electrode.

11. Collecting an electrolytic solution from a plating bath or an electrolytic solution storage tank for supplying the electrolytic solution; Adjusting the concentration of the electrolytic solution in a stock solution state or a state diluted at a predetermined ratio by selectively diluting the electrolytic solution with a diluent at a predetermined ratio; Irradiating light on the electrolytic solution with the adjusted concentration to analyze the light absorption characteristics of the electrolytic solution with the adjusted concentration and analyze the composition of the electrolytic solution; Adjusting the composition of the electrolytic solution in the plating bath based on the difference between the analyzed composition of the electrolytic solution and a preset composition of the electrolytic solution, A method for managing an electrolytic solution, characterized in that when analyzing the light absorption characteristics in the ultraviolet region, the electrolytic solution and the diluent are analyzed in a state diluted at a predetermined ratio.

12. The diluent contains water (H ２ O), has no light absorption in the wavelength range of 200 to 500 nm, and is diluted 2 to 400 times the volume of the electrolyte, and the method for managing the electrolyte according to claim 11.

13. The method for managing an electrolytic solution according to claim 11, characterized in that when analyzing the light absorption characteristics in a wavelength region of 300 to 1000 nm, the electrolytic solution is analyzed in a stock solution state without dilution.

14. The step of analyzing the light absorption characteristics is A first spectroscopic analysis step of analyzing a wavelength region of 10 to 500 nm; The method for managing an electrolytic solution according to claim 11, characterized by including a second spectroscopic analysis step of analyzing a wavelength region of 300 to 1000 nm.

15. The method for managing an electrolytic solution according to claim 11, characterized in that the analysis of the electrolytic solution composition includes a step of processing data obtained by analyzing the light absorption characteristics by multivariate calibration.

16. The electrolytic solution contains Fe ２＋ , Ni ２＋ and saccharin, and is characterized in that it is a method for managing the electrolytic solution according to claim 11.

17. The electrolyte management method according to claim 16, wherein the electrolyte further contains an antioxidant.

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