JP2003077768A - Method for manufacturing solid electrolytic capacitor and solid electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a solid electrolytic capacitor in which the problem that residual stress is generated in an anode body through grooving at a specified position thereof and twist or warp takes place in the anode body at the grooved part. SOLUTION: Since a plurality of through holes 2a are formed linearly at constant intervals at specified positions of an anode body 2, and linear grooves are formed symmetrically on the surface and rear by pressing specified positions of the anode body including the through holes 2a from the surface and rear, the generation of residual stress in the anode body is retarded and the grooved part is not twisted nor warped, thus realizing stabilization of production while enhancing the production efficiency and stabilizing the quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a solid electrolytic capacitor used in various electronic devices and a solid electrolytic capacitor.

[0002]

2. Description of the Related Art FIG. 6 is a partially cutaway perspective view showing the structure of a conventional solid electrolytic capacitor of this type. In FIG. 6, reference numeral 21 denotes a capacitor element.
1 is separated into an anode lead-out portion 23 and a cathode lead-out portion 24 by attaching a polyimide adhesive tape 25 to a predetermined position of an anode body 22 obtained by roughening the surface of an aluminum foil which is one of valve action metals by etching. Then, a solid electrolyte layer 26 made of a conductive polymer is formed on the surface of the anode body 22 of the cathode lead portion 24, and a cathode layer 29 made of a carbon paint layer 27 and a silver paint layer 28 is further formed on the solid electrolyte layer 26. Are sequentially laminated.

Then, the anode lead terminal 30 is connected to the anode lead-out portion 23 of the capacitor element 21 thus constructed, and the cathode lead terminal 31 is connected to the anode lead-out portion 24, and then the anode lead terminal 30 and the cathode are connected. The capacitor element 21 is formed by coating the above-mentioned capacitor element 21 with an insulating exterior resin 32 in a state in which a part of the lead terminal 31 is exposed to the outside.

[0004]

However, in the above-mentioned conventional solid electrolytic capacitor, the anode body 22 made of aluminum foil having the surface roughened and provided with the roughened layer is provided with the polyimide adhesive tape 25 to the anode lead portion 23 and the cathode. Although the lead-out portion 24 is separated, when the solid electrolyte layer 26 is formed on the cathode lead-out portion 24, the solid electrolyte is passed from the cathode lead-out portion 24 to the anode lead-out portion through the gap between the polyimide adhesive tape 25 and the roughened layer. However, there is a problem in that it may reach 23 and cause insulation failure, or in some cases dielectric breakdown may occur.

For this reason, the width of the polyimide adhesive tape 25 is widened, a material having high adhesion to the anode body 22 made of aluminum foil is used, or the predetermined size of the anode body 22 to which the polyimide adhesive tape 25 is attached. An attempt has been made to crush the roughened layer formed on the surface by grooving the position by means such as press working, thereby preventing the solid electrolyte from entering the anode lead-out portion 23. It was

However, the above-mentioned polyimide adhesive tape 2
Even if the width of No. 5 is widened or a material having high adhesion to the anode body 22 is used, it is difficult to always obtain a stable effect for many production lots. When grooving is performed at a predetermined position of the anode body 22 to be attached, the aluminum foil forming the anode body 22 is crushed around the groove by this grooving and stretches so as to escape. Due to unevenness, residual stress is generated inside the aluminum foil, resulting in twisting and warping of the grooved aluminum foil, which reduces productivity and production efficiency. In addition, there is a problem that the quality is adversely affected.

The present invention solves such conventional problems,
(EN) A solid electrolytic capacitor manufacturing method and a solid electrolytic capacitor which are excellent in productivity, in which the quality of the product is reliably stabilized by ensuring the insulation between the anode lead-out part and the cathode lead-out part and twisting and warping do not occur. The purpose is to do.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention, in particular, provides a predetermined valve action metal foil having a surface roughened to form a dielectric oxide film layer. A plurality of through holes are linearly provided at regular intervals at positions, and then a predetermined position including the above through holes is pressed from the front and back surfaces to form linear groove portions symmetrically between the front and back surfaces. As an anode body separated into an anode lead-out portion and a cathode lead-out portion is manufactured, subsequently, a groove portion of the anode body is subjected to an insulation treatment, and then a solid electrolyte layer and a cathode layer are sequentially laminated on the surface of the cathode lead-out portion. To form a capacitor element, connect the cathode lead terminal to the cathode layer of the capacitor element, and connect the anode lead terminal to the anode lead portion, and expose the anode lead terminal and a part of the cathode lead terminal to the outer surface, respectively. This is a method of manufacturing a solid electrolytic capacitor in which the above-mentioned capacitor element is covered with an insulating exterior resin in such a state that there is no twisting or warping of the valve metal foil, and there is no residual stress inside. To provide a method for manufacturing a solid electrolytic capacitor that is excellent in productivity while performing groove processing that does not easily generate heat to ensure the insulation between the anode lead portion and the cathode lead portion to stabilize quality. It has the effect of being able to

According to a second aspect of the present invention, in the invention according to the first aspect, the insulation treatment applied to the groove portion of the anode body separated into the anode lead portion and the cathode lead portion with the groove portion as a boundary is heat-resistant. This is done by attaching a heat resistant tape coated with a flexible silicone adhesive to the groove, and this method makes it possible to perform reliable work easily and reliably. Has an effect.

According to a third aspect of the present invention, in the invention according to the first aspect, a continuous strip-shaped foil wound around a reel is used as the valve action metal foil. Therefore, it has an effect that highly accurate work can be continuously and efficiently performed.

According to a fourth aspect of the present invention, there is provided a solid electrolytic capacitor manufactured by using the manufacturing method according to the first aspect, wherein a groove portion for separating the anode body into an anode lead portion and a cathode lead portion. It is configured such that a part of the through-holes provided on the capacitor element remain at both ends of the groove portion of the capacitor element, respectively, thereby ensuring the insulation between the anode lead portion and the cathode lead portion and ensuring the quality, It has an effect that a solid electrolytic capacitor having excellent reliability can be stably provided.

According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the valve action metal foil is made of any one or more of aluminum, tantalum, niobium, zircon, titanium, or an alloy thereof. With this configuration, the function and effect of the invention according to claim 4 can be obtained more efficiently.

According to a sixth aspect of the present invention, in the invention according to the fourth aspect, the solid electrolyte layer comprises a hetero five-membered ring compound as a monomer and a dielectric material thereof, and the dopant is an aryl sulfonic acid or an alkyl phosphorus. It is configured to be formed by electrolytic oxidative polymerization using at least one of acid esters, and thereby, the function and effect of the invention according to claim 4 can be obtained more efficiently. Have.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the inventions particularly described in claims 1 to 6 of the present invention will be described using an embodiment of the present invention.

FIG. 1 is a partially cutaway perspective view showing the structure of a solid electrolytic capacitor according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a capacitor element, which is made of a valve metal. A plurality of through-holes 2a are linearly provided at predetermined positions on the anode body 2 whose surface is roughened by etching, and are pressed at a predetermined position including the through-holes 2a. The anode lead-out portion 3 is formed by attaching a polyimide adhesive tape 5 on a groove (not shown) formed in a straight line by processing.
And a cathode lead-out portion 4, and a solid electrolyte layer 6 made of a conductive polymer on the surface of the anode body 2 of the cathode lead-out portion 4.
And a cathode layer 9 composed of a carbon paint layer 7 and a silver paint layer 8 are sequentially laminated on the solid electrolyte layer 6.

Reference numerals 10 and 11 denote an anode lead terminal connected to the anode lead-out portion 3 and a cathode lead terminal connected to the cathode lead-out portion 4 of the capacitor element 1 thus constructed, and 12 denotes the anode lead terminal 10 described above. Cathode lead terminal 1
1 is an insulating exterior resin that covers the capacitor element 1 in a state in which a part of each is exposed to the outside.

Next, a method of manufacturing the solid electrolytic capacitor of the present embodiment having the above-mentioned structure will be described.
First, as shown in FIGS. 2A and 2B, a continuous strip-shaped aluminum foil is etched to roughen the surface to provide a roughened layer (not shown), which is then anodized. Dielectric oxide layer (not shown) on the surface of the roughened layer
A plurality of through-holes 2a are linearly provided at predetermined positions on the anode body 2 in which the holes are formed.

In the present embodiment, in order to continuously manufacture a plurality of capacitor elements 1, the through holes 2a are linearly arranged in two rows so as to form two rows in the width direction of the anode body 2. It is provided.

Subsequently, as shown in FIGS. 3 (a) and 3 (b),
By pressing from the front and back surfaces of the anode body 2 at predetermined positions including the through holes 2a provided in the anode body 2, linear groove portions 2b are formed symmetrically on the front and back sides, and the anode lead portion 3 with the groove portion 2b as a boundary. The anode body 2 separated into the cathode lead-out portion 4 is manufactured.

Subsequently, as shown in FIG. 4, the polyimide adhesive tape 5 is attached on the linear groove portion 2b provided in the anode body 2 to perform insulation treatment, and thereafter, to obtain the individual capacitor element 1. The punching process (the punching process part 13) is performed as one of the steps.

Then, a solid electrolyte layer 6 made of polypyrrole, which is a conductive polymer, is formed on the surface of the cathode lead portion 4 by electrolytic oxidation polymerization, and a carbon paint layer 7 and a silver paint are further formed on the solid electrolyte layer 6. After sequentially stacking and forming the cathode layer 9 including the layer 8, a punching process (punching process portion 14), which is one of the steps for obtaining the individual capacitor element 1, is performed to obtain a capacitor as shown in FIG. The element 1 is obtained.

After that, the cathode lead terminal 11 is connected to the cathode layer 9 of the capacitor element 1 thus constructed, and the anode lead terminal 10 is connected to the anode lead portion 3, and the anode lead terminal 10 and the cathode lead terminal are connected. 1
The solid electrolytic capacitor according to the present embodiment is manufactured by coating the capacitor element 1 with an insulating exterior resin 12 in a state in which a part of each is exposed to the outer surface.

In the solid electrolytic capacitor according to the present embodiment having the above-described structure, before the predetermined position of the anode body 2 is pressed from the front and back surfaces to form the linear groove portion 2b symmetrically between the front and back surfaces, this groove portion is formed. By arranging a plurality of through holes 2a linearly at regular intervals at positions included in 2b,
Stabilization of production and production efficiency are solved by solving the problems that have been encountered in the past, such as the twisting and warping of the grooved portion of the anode body caused by the groove processing that was performed at predetermined positions on the anode body. As shown in FIG. 5, the through holes 2a linearly formed at a predetermined interval in the anode body 2 form the anode lead-out portion 3 of the capacitor element 1 and the cathode layer. Since it is arranged so as to be located at both ends of the part for separating 9 respectively, residual stress is less likely to occur inside the anode body 2 and the quality can be stabilized at the same time.

In the present embodiment, the solid electrolyte layer 6
In the above description, pyrrole was used as the conductive polymer material constituting the above. However, the same effect as pyrrole can be obtained by using a hetero five-membered ring compound such as thiophene.

Although an aluminum foil is used as an example of the valve metal foil which constitutes the anode body 2, any one of tantalum, niobium, zircon and titanium, or a composite or alloy thereof is also used. Can be used to obtain the same effect as the aluminum foil.

[0026]

As described above, according to the method for manufacturing a solid electrolytic capacitor of the present invention, a plurality of through holes are linearly provided at predetermined positions at predetermined positions of the valve action metal foil having the dielectric oxide film layer, A predetermined position including this through hole is pressed from the front and back surfaces of the valve action metal foil to form linear groove portions symmetrically on the front and back sides, whereby the anode separated into the anode lead portion and the cathode lead portion with the groove portion as a boundary. By adopting the manufacturing method of manufacturing the body, it is possible to solve the problem that the anode body in the grooved portion is twisted or warped at once, and stabilize the production and improve the production efficiency. In addition, the through holes provided in the anode body are arranged so as to be located at both ends of the part that separates the anode lead-out portion and the cathode layer of the capacitor element, respectively. Occurred Kuna' Te are those so can be realized at the same time stable quality, its contribution are those large becomes.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a configuration of a solid electrolytic capacitor according to an embodiment of the present invention.

FIG. 2A is a plan view of an anode body having through holes for explaining the manufacturing method, and FIG.

FIG. 3A is a plan view of an anode body provided with a groove for explaining the manufacturing method, and FIG. 3B is a side view of the same.

FIG. 4 is a plan view of an anode body subjected to insulation treatment for explaining the manufacturing method.

FIG. 5 is a partially cutaway perspective view showing the configuration of the capacitor element.

FIG. 6 is a partially cutaway perspective view showing a configuration of a conventional solid electrolytic capacitor.

[Explanation of symbols]

1 Capacitor element 2 Anode body 2a through hole 2b groove 3 Anode drawer 4 Cathode drawer 5 Polyimide adhesive tape 6 Solid electrolyte layer 7 Carbon paint layer 8 silver paint layer 9 cathode layer 10 Anode lead terminal 11 Cathode lead terminal 12 Exterior resin 13,14 punching part

Claims (6)

[Claims] 1. A surface of a valve metal foil is roughened, a dielectric oxide film layer is formed on the surface, and a plurality of through holes are linearly formed at predetermined positions of the valve metal foil at regular intervals. Provided,
Subsequently, a predetermined position including the through hole is pressed from the front and back surfaces of the valve action metal foil to form linear groove portions symmetrically on the front and back sides, thereby separating the anode lead portion and the cathode lead portion with the groove portion as a boundary. After manufacturing the anode body, the groove portion of the anode body is subjected to an insulation treatment, and then a solid electrolyte layer and a cathode layer are sequentially laminated on the surface of the cathode lead portion to form a capacitor element. The cathode lead terminal is connected to the cathode layer and the anode lead terminal is connected to the anode lead portion, and the capacitor element is insulated with the insulating exterior in a state where the anode lead terminal and a part of the cathode lead terminal are exposed to the outer surface, respectively. A method for manufacturing a solid electrolytic capacitor coated with a resin. 2. The insulating treatment applied to the groove portion of the anode body separated into the anode lead-out portion and the cathode lead-out portion with the groove portion as a boundary is that a heat-resistant tape coated with a heat-resistant silicon adhesive is applied to the groove portion. The method for producing a solid electrolytic capacitor according to claim 1, wherein 3. The method for producing a solid electrolytic capacitor according to claim 1, wherein the valve action metal foil is a continuous strip wound on a reel. 4. A solid electrolytic capacitor manufactured by using the manufacturing method according to claim 1, wherein a part of a through hole formed in a groove for separating the anode body into an anode lead portion and a cathode lead portion is a capacitor. A solid electrolytic capacitor that is left on both ends of the groove of the device. 5. The solid electrolytic capacitor according to claim 4, wherein the valve metal foil is made of one or more of aluminum, tantalum, niobium, zircon, titanium, or an alloy thereof. 6. The solid electrolyte layer, wherein the monomer is a hetero five-membered ring compound and its dielectric, and the dopant is formed by electrolytic oxidative polymerization using at least one of aryl sulfonic acid or alkyl phosphoric acid ester. The solid electrolytic capacitor according to claim 4.