JP2004076050A - Electrode for electroplating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode for electroplating, which can be freely transformed in response to a complex shape of an article to be treated, and does not cause a voltage drop in a length direction, elution of a composing metal or a deposition phenomenon of sludge. <P>SOLUTION: This electrode comprises a long carbon fiber 11, an electroconductive clamping member 13 for clamping the upper end of the carbon fiber 11 through the soft metal 12, a first bag 14 composed of a cloth or a net for encircling the outside of the above carbon fiber, and a second bag 15 composed of the cloth or the net for encircling the outside of the first bag 14. Then, the electrode can be freely transformed in response to the complex shape of the article to be treated, and prevents the voltage drop in the length direction, the elution of the composing metal or the deposition phenomenon of the sludge. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrode for electroplating, which is effective when electroplating a complex shape inside or outside surface or a large or long object with metal.
[0002]
[Prior art]
Generally, electrodes used as anodes for electroplating have (1) sufficient electrical conductivity to maintain a uniform current distribution over the entire electrode, and (2) chemical erosion by a plating bath solution. In addition to (3) it is necessary to have flexibility to cope with a workpiece having a complicated shape.
Conventionally, metal fibers such as stainless steel have been mainly used as flexible electrodes. Further, carbonaceous materials are widely used in terms of excellent electrical conductivity and chemical stability.
[0003]
Further, the use of carbon fiber (carbon fiber) as an electrode for electroplating has been studied because of its excellent electrical properties, chemical stability and mechanical properties, and a plurality of carbon fibers are bundled in a circumferential direction at predetermined intervals. Electroplated electrodes for binding have also been proposed.
[0004]
[Problems to be solved by the invention]
However, when a metal fiber such as stainless steel is used in the conventional electrode for electroplating having the above-described configuration, the voltage drop in the length direction of the electrode is remarkable, and the elution of the electrode constituent metal or the adhesion of sludge is caused. This caused a phenomenon, and there was a problem in terms of electrical characteristics and corrosion resistance.
Further, when a carbonaceous material is used, it is not possible to cope with a workpiece having a complicated shape due to lack of flexibility.
[0005]
In the above-mentioned electrode for electroplating using carbon fiber, carbon fiber was originally developed as a composite material with a synthetic resin, and exhibits various physical properties only when used as a composite material. However, when used as an electrode, the electric resistance increases and there is a problem in the connection between the terminal connected to the conductive wire. Further, there is a drawback that dust in the treatment liquid is entangled with the fine carbon fibers and adheres to the surface to increase the surface resistance and decrease the current-carrying performance. Further, dust easily adheres to the portion where the carbon fibers are tied, and the dust once adhered cannot be easily removed. This is because carbon fibers are so thin that they cannot exert a large stress during cleaning. Furthermore, when carbon fibers are bundled and bound in the circumferential direction as in the conventional case, the solution is shaken by the vibration of the device or the insertion / removal of the workpiece, whereby the electrode is repeatedly bent, and the fiber on the outer surface with respect to the center of the electrode is The fiber was repeatedly subjected to tensile and compressive stresses, causing slippage between the fibers, causing the fibers to break.
In addition, tying in the circumferential direction itself gives a local bending load to the fiber. These phenomena become larger as the binding is made stronger, the binding pitch is smaller, and the length is longer. Note that the strength of binding the carbon fiber is shifted in the axial direction unless it is bound to a certain degree.
Furthermore, since there is almost no gap between the carbon fibers in the portion bound in the circumferential direction, the contact area between the treatment liquid and the carbon fibers is reduced, and the current-carrying performance is significantly reduced. Further, there is a possibility that the cooling effect of the processing liquid is reduced, and when a large current is applied, heat is generated to increase the electric resistance.
[0006]
The present invention has been proposed in view of the above-mentioned circumstances, and can be freely deformed in accordance with the complicated shape of an object to be processed, and causes a voltage drop in a length direction, elution of constituent metals or a phenomenon of sludge adhesion. An object of the present invention is to provide an electrode for electroplating that does not need to be performed.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 includes a long carbon fiber, a conductive clamp member for clamping an upper end of the carbon fiber via a soft metal, and an outer periphery of the carbon fiber. It is provided with a first bag made of a cloth or a net to be covered.
[0008]
Further, the invention according to claim 2 is characterized in that a second bag made of a cloth or a net further enclosing the outside of the first bag is provided.
[0009]
Further, in the invention according to claim 3, the carbon fiber is made of a unidirectional woven fabric.
[0010]
Further, in the invention described in claim 4, the soft metal clamps the carbon fiber between opposed gentle convex curved surfaces.
[0011]
Further, in the invention described in claim 5, the soft metal is a plurality of wires.
[0012]
Further, in the invention according to claim 6, the soft metal is a plurality of pipe members.
[0013]
Further, in the invention described in claim 7, the soft metal is lead.
[0014]
Further, in the invention described in claim 8, the soft metal is copper.
[0015]
According to the ninth aspect of the present invention, the second bag is made of a cloth or a net that is coarser than the first bag.
[0016]
Further, in the invention according to claim 10, the periphery of the conductive clamp member is sealed with a synthetic resin or soft rubber.
[0017]
Further, in the invention according to claim 11, the lower end of the first bag body is configured to be opened and closed by a cord.
[0018]
In the twelfth aspect of the present invention, the lower end of the second bag body can be opened and closed by a cord.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings showing one embodiment. FIG. 1 is a partially omitted front view showing an example of the electroplating electrode according to the present invention, FIG. 2 is a side view partially omitted of the electroplating electrode of the present invention, and FIG. It is a principal part expanded sectional view of the electrode for plating.
[0020]
Here, the electrode 10 for electroplating includes a long carbon fiber 11, a conductive clamp member 13 for clamping an upper end 11 a of the carbon fiber 11 via a soft metal 12, and surrounds the outside of the carbon fiber 11. A first bag body 14 made of a cloth or a mesh to be formed, and a second bag body 15 made of a cloth or a net further surrounding the outside of the first bag body 14 are provided.
[0021]
The conductive clamp member 13 includes a conductive terminal plate 13 a having a fixing hole 16, a fixing member 13 b having a lower end and an open side surface facing the terminal plate 13 a, a plurality of fixing bolts 17, and the like. As shown in FIG. 3, the soft metal 12 is disposed so that the convex surfaces that are curved to each other face each other, and the fixing bolt 17 penetrates. Therefore, by tightening the fixing bolt 17, the upper end 11 a of the carbon fiber 11 held between the soft metals 12 is pressed, and electrical conduction with the conductive clamp member 13 is obtained. The soft metal 12 has a plate shape convexly curved, and can clamp the carbon fiber 11 between opposed gentle convex curved surfaces. Further, as the soft metal 12, a metal such as lead or copper can be optimally used.
[0022]
When the soft metal 12 is configured to have a gentle convex curved surface facing as described above, it is possible to disperse the pressing force at the contact portion between the conductive clamp member 13 and the carbon fiber 11 and prevent the carbon fiber 11 from breaking. Reliable contact can be obtained. In addition, since it is fixed by the fixing bolt 17, attachment and detachment are easy, and replacement work is easy.
[0023]
In addition, the soft metal 12 may be composed of a plurality of wires or pipe materials 18 according to the amount of electricity as shown in FIG. When the soft metal 12 is composed of a plurality of wires or pipe members 18 as described above, the structure of the soft metal 12 can be simplified and can be manufactured at low cost.
[0024]
The carbon fibers 11 used in the present invention are made of carbonaceous fiber tows produced by firing and carbonizing organic synthetic fibers of acrylic or rayon type. The carbon fiber 11 is used after being cut to an arbitrary length according to the shape of the object to be treated, and is desirably lightly twisted or lightly knitted to avoid dispersion and clutter of the single fiber. Formed. At this time, twisting or knitting too strongly promotes internal heat generation of the electrode, which is not preferable. Also, by connecting a plurality of string-shaped electrodes to a single conductive clamp member 13, an octopus-shaped branch electrode can be formed. In particular, when processing a complicated object to be treated, the carbon fibers 11 can be inserted into a porous tube of a soft synthetic resin having electrical insulation properties or a cloth bag of glass fibers to form an electrode. Furthermore, a string of a soft synthetic resin or glass fiber may be spirally wound around the electrode to prevent contact between the object and the electrode.
[0025]
The first bag body 14 is made of a cloth or a net made of polyethylene, polyester, Teflon (registered trademark) or the like having acid resistance, alkali resistance, and chemical resistance. Is held by The lower end of the first bag body 14 is configured to be openable and closable, and is confined by, for example, a cord 19. The second bag 15 is made of a cloth or a net having acid resistance, alkali resistance, and chemical resistance similarly to the first bag 14, and the upper end is fixed to the outer periphery of the conductive clamp member 13 by the fixing member 20. Fixed. The lower end of the second bag 15 is also configured to be openable and closable, for example, is bound by a cord 21. Further, the second bag body 15 is made of a cloth or a net that is coarser than the first bag body 14, and a fixing cord 22 is attached at an appropriate position, and the second bag body 15 is tied to a fixing material (not shown). Can be attached.
[0026]
By attaching the weight 23 to the lower end of the second bag 15, the electrode 10 for electroplating can be stabilized in the processing tank. The periphery of the conductive clamp member 13 is sealed with a synthetic resin or soft rubber 24. By sealing the periphery of the conductive clamp member 13 with these materials, it is possible to prevent corrosion due to the processing liquid.
[0027]
The carbon fiber 11 used in the present invention is a tow composed of a bundle of many single fibers having a diameter of several microns, and has a remarkably large surface area as compared with a conventional electrode. Therefore, the electrolysis efficiency during plating is extremely high.
Experimental example 1
Using a copper-tin-nickel alloy plating solution, plating was performed at a voltage of 3 V, a current density of 2.5 A / 10 dm ² , a bath temperature of 20 ° C., a time of 2 minutes, and a pH of 8.5. When plating was performed under the above standard conditions, good results could be obtained.
[0028]
It has been experimentally confirmed that the electrode for electroplating configured as described above has a small voltage drop in the length direction and has a substantially uniform current distribution throughout. It is presumed that the reason depends on the graphite crystal orientation of the carbon fibers constituting the electrode. In other words, it is considered that graphite crystallites are oriented parallel to the fiber axis direction in the step of calcining and carbonizing the raw yarn of the carbon fiber, and the electrical conductivity in the length direction is remarkably improved. This ordered crystal orientation is promoted by heat treatment while applying tension to the yarn.
[0029]
5A and 5B show another embodiment of the present invention, in which FIG. 5A is a cross-sectional view showing a conductive clamp member of an electrode for electroplating of the present invention, and FIG. 5B is a woven fabric made of carbon fiber. It is a top view which shows the example which laminated | stacked (carbon cloth) 1 to 4 respectively. The woven fabric (carbon cloth) 25 is woven in a belt shape using carbon fiber as a warp and synthetic fibers such as polyethylene as a weft. Further, the woven fabric 25 may be used by laminating a required number of these carbon cloths.
[0030]
In the case of the above configuration, since the carbon powder has flexibility as compared with the electrode sintered with carbon powder, there is no possibility that the broken or worn carbon powder is dispersed in the processing liquid and adversely affects the finished product. . Further, since it is flexible and can be transported and stored in a wound state, it is easy to handle.
[0031]
Depending on the conditions of use, only the first bag 14 can be used as an electrode for electroplating.
[0032]
6A and 6B show another embodiment of the present invention, in which FIG. 6A is a cross-sectional view showing an example of a reinforced electrode for electroplating of the present invention, and FIG. 6B is an electrode for electroplating of the present invention. It is a principal part front view which shows the example which reinforced. In the present embodiment, a pipe-like reinforcing material 26 is arranged along the woven fabric 25 and is fixed by a fixing member 27 at an appropriate position. With this configuration, it is possible to prevent the electrode for electroplating from being carelessly deformed in the processing solution.
[0033]
7A and 7B show another embodiment of the present invention, in which FIG. 7A is a cross-sectional view showing an example of a reinforced electrode for electroplating of the present invention, and FIG. 7B is an electrode for electroplating of the present invention. It is a principal part front view which shows the example which reinforced. In the present embodiment, a pipe-like reinforcing material 28 is arranged along the woven fabric 25 and is fixed by a fixing cord 29 at an appropriate position. With this configuration, it is possible to prevent the electrode for electroplating from being carelessly deformed in the processing solution.
[0034]
FIG. 8 is a main part front view showing another embodiment of the present invention. In the present embodiment, the upper end 11a of the carbon fiber 11 is provided with a metal plating 30. As shown in an enlarged view in FIG. 9, metal plating is performed on a portion of the upper end of the carbon fiber 11 where the conductive clamp member 13 is to be mounted.
[0035]
With such a configuration, the contact between the conductive clamp member 13 that supplies the current and the carbon fiber 11 is improved, and the conductivity at the connection portion can be significantly improved.
[0036]
FIG. 10 is a main part front view showing another embodiment of the electrode for electroplating of the present invention. In the present embodiment, the metal plating 30 is applied to the upper end 11a of the carbon fiber 11 and the metal plating 30 is applied to the conductive clamp member 31 at the same time.
[0037]
With such a configuration, the contact between the upper end 11a of the carbon fiber 11 and the conductive clamp member 31 can be further improved.
[0038]
FIG. 11 is an experimental example showing a comparison between the electrode for electroplating of the present invention and a conventional voltage. The example shown as S-1 by the solid line is the electrode for electroplating according to the present invention. No abnormality is observed even when a voltage of 5V to 15V is applied, and even when a voltage of 15V or more is applied, the current is proportionally increased. There was an increase. On the other hand, the electrode connected to the conventional pressure terminal shown by the broken line emitted smoke when a voltage of 12 to 15 V was applied. Further, even if the same voltage is applied to the conductive clamp member having a large contact resistance, the current flowing through the electrode is extremely small.
[0039]
As described above, in the present invention, the contact resistance between the conductive clamp member and the carbon fiber 11 is small, and a current proportional to the voltage applied to the conductive clamp member flows. Further, even if the applied voltage is 12 to 15 V, there is no possibility that a smoke phenomenon occurs at the connection portion. On the other hand, the conventional electrode produced a smoke phenomenon and was not usable.
[0040]
【The invention's effect】
Since the present invention has the above-described configuration, the following effects can be obtained.
[0041]
According to the first aspect of the present invention, the carbon fiber comprises a long carbon fiber, a conductive clamp member for clamping an upper end of the carbon fiber via a soft metal, and a cloth or net surrounding the outside of the carbon fiber. And a first bag body.
[0042]
With such a configuration, it is not necessary to bind the carbon fibers in the circumferential direction, so that the carbon fibers can be prevented from being broken by an external force. In addition, the carbon fibers and the processing liquid can be uniformly contacted in the longitudinal direction, and there is no unevenness in current supply. Further, since the carbon fibers are surrounded by the first bag, it is possible to prevent dust in the treatment liquid from adhering to the surface of the carbon fibers and prevent an increase in electric resistance. Further, the workpiece can be freely deformed corresponding to the complicated shape of the workpiece, and the voltage drop in the length direction can be reduced.
[0043]
According to the second aspect of the present invention, since the first bag is provided with the second bag made of a cloth or a net that further surrounds the outside of the first bag, dust in the processing liquid is deposited on the carbon fiber surface. The first bag body and the second bag body can be prevented from sticking to each other, so that an increase in electric resistance can be prevented. Further, the workpiece can be freely deformed corresponding to the complicated shape of the workpiece, and the voltage drop in the length direction can be reduced.
[0044]
Further, in the invention described in claim 3, since the carbon fiber is made of a unidirectional woven fabric, the carbon fiber is rich in flexibility and does not have a possibility of being bent or worn.
[0045]
Further, in the invention according to claim 4, the soft metal clamps the carbon fiber between the opposed gentle convex curved surfaces, so that the pressing force in the holding portion is dispersed to prevent the carbon fiber from breaking. can do.
[0046]
Further, in the invention described in claim 5, since the soft metal is a plurality of wires, the structure is simple and the carbon fibers can be reliably held according to the amount of electricity.
[0047]
Further, in the invention described in claim 6, since the soft metal is a plurality of pipe members, the structure is simple and the carbon fibers can be reliably held according to the amount of electricity.
[0048]
Further, in the invention according to claim 7, since the soft metal is lead, it is possible to prevent the carbon fibers from breaking while maintaining the electrical conductivity with the conductive clamp member.
[0049]
Further, in the invention according to claim 8, since the soft metal is copper, it is possible to prevent the carbon fibers from breaking while maintaining the electrical conductivity with the conductive clamp member.
[0050]
According to the ninth aspect of the present invention, since the second bag body is made of a cloth or a net that is coarser than the first bag body, the outer second bag is formed by dust in the processing liquid. The body can be prevented from being clogged first.
[0051]
In the invention according to claim 10, the periphery of the conductive clamp member is sealed with a synthetic resin or soft rubber, so that the conductive clamp member itself can be prevented from being corroded by the processing liquid. .
[0052]
Further, in the invention according to claim 11, since the lower end of the first bag is configured to be openable and closable by a string, the lower end of the bag is clogged or contaminated by dust or the like. The filter can be easily removed by opening the section, blowing clean water or the like, and performing reverse washing to restore the normal filter function. In addition, the maintenance and inspection of the carbon fiber can be directly performed.
[0053]
According to the twelfth aspect of the present invention, since the lower end of the second bag is configured to be openable and closable by a string, the lower end of the bag is opened when the bag is clogged or contaminated with dust or the like. The normal filter function can be easily restored by blowing back water and blowing clean water. In addition, the maintenance and inspection of the carbon fiber can be directly performed by opening the bag.
[Brief description of the drawings]
FIG. 1 is a partially omitted front view showing an example of an electrode for electroplating according to the present invention.
FIG. 2 is a side view in which a part of the electrode for electroplating is omitted.
FIG. 3 is an enlarged sectional view of a main part of the electrode for electroplating.
FIG. 4 is an enlarged sectional view of a main part showing another embodiment of the electrode for electroplating of the present invention.
FIG. 5 (a) is a cross-sectional view showing a conductive clamp member of the electrode for electroplating, and FIG. 5 (b) is a plan view showing an example in which woven fabrics made of carbon fibers are overlapped by 1 to 4 respectively. It is.
FIG. 6A is a cross-sectional view showing an example in which the electrode for electroplating is reinforced, and FIG. 6B is a front view of a main part showing an example in which the electrode for electroplating is reinforced.
FIG. 7A is a cross-sectional view showing an example in which the electrode for electroplating is reinforced, and FIG. 7B is a front view of a main part showing an example in which the electrode for electroplating is reinforced.
FIG. 8 is a front view of a main part showing another embodiment of the electrode for electroplating.
FIG. 9 is an enlarged front view of a portion A in FIG. 8;
FIG. 10 is a main part front view showing another embodiment of the electrode for electroplating of the present invention.
FIG. 11 is an experimental example showing a comparison between the electrode for electroplating of the present invention and a conventional voltage.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Electroplating electrode 11 Carbon fiber 11a Upper end 12 Soft metal 13 Conductive clamp member 14 First bag 15 Second bag 16 Fixing hole 17 Fixing bolt 18 Wire, pipe material 19 String 20 Fixing member 21 String 22 String 23 Weight 24 Synthetic resin, soft rubber 25 Woven cloth (carbon cloth)
26, 28 Reinforcement material 27 Fixing member 29 Fixing string 30 Metal plating

Claims (12)

A long carbon fiber, a conductive clamp member for clamping an upper end of the carbon fiber via a soft metal, and a first bag body made of a cloth or a net surrounding the outside of the carbon fiber. An electrode for electroplating, characterized in that: 2. The electrode for electroplating according to claim 1, further comprising a second bag made of cloth or a net further surrounding the outside of the first bag. 3. The electrode for electroplating according to claim 1, wherein the carbon fiber is made of a unidirectional woven fabric. The electrode for electroplating according to any one of claims 1 to 3, wherein the soft metal clamps the carbon fiber between opposing gentle convex curved surfaces. The electrode for electroplating according to any one of claims 1 to 4, wherein the soft metal is a plurality of wires. The electrode for electroplating according to any one of claims 1 to 5, wherein the soft metal is a plurality of pipe materials. The electrode for electroplating according to claim 1, wherein the soft metal is lead. The electrode for electroplating according to claim 1, wherein the soft metal is copper. The electrode for electroplating according to any one of claims 2 to 8, wherein the second bag is made of a cloth or a net that is coarser than the first bag. The electroplating electrode according to any one of claims 1 to 9, wherein a periphery of the conductive clamp member is sealed with a synthetic resin or soft rubber. The electrode for electroplating according to any one of claims 1 to 10, wherein a lower end portion of the first bag body is configured to be opened and closed by a string. The electrode for electroplating according to any one of claims 2 to 11, wherein a lower end portion of the second bag body is configured to be opened and closed by a string.

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