JP4806874B2 - Solid electrolytic capacitor manufacturing method and solid electrolytic capacitor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a solid electrolytic capacitor used in various electronic devices and a solid electrolytic capacitor.
[0002]
[Prior art]
FIG. 6 is a partially cutaway perspective view showing the configuration of this type of conventional solid electrolytic capacitor. In FIG. 6, reference numeral 21 denotes a capacitor element, and this capacitor element 21 is aluminum which is one of valve action metals. A polyimide adhesive tape 25 is attached to a predetermined position of the anode body 22 whose surface is roughened by etching to separate it into an anode lead portion 23 and a cathode lead portion 24. A structure in which a solid electrolyte layer 26 made of a conductive polymer is formed on the surface, and a cathode layer 29 made up of a carbon paint layer 27 and a silver paint layer 28 is sequentially laminated on the solid electrolyte layer 26. It is.
[0003]
Then, the anode lead terminal 30 is connected to the anode lead portion 23 of the capacitor element 21 configured as described above, and the cathode lead terminal 31 is connected to the anode lead portion 24, and then the anode lead terminal 30 and the cathode lead terminal 31 are connected. The capacitor element 21 is covered with an insulating exterior resin 32 in a state where a part of each is exposed to the outside.
[0004]
[Problems to be solved by the invention]
However, in the conventional solid electrolytic capacitor, the anode body 22 made of an aluminum foil having a roughened surface and a roughened layer is separated into an anode lead portion 23 and a cathode lead portion 24 by a polyimide adhesive tape 25. However, when the solid electrolyte layer 26 is formed on the cathode lead portion 24, the solid electrolyte reaches the anode lead portion 23 from the cathode lead portion 24 through the gap between the polyimide adhesive tape 25 and the roughened layer. There has been a problem that an insulation failure is caused, or a case where dielectric breakdown occurs rarely occurs.
[0005]
For this purpose, 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 a predetermined position of the anode body 22 to which the polyimide adhesive tape 25 is attached is pressed. Attempts have been made to crush the roughened layer formed on the surface by grooving by means such as processing, thereby preventing the solid electrolyte from entering the anode lead-out portion 23.
[0006]
However, even if the width of the polyimide adhesive tape 25 is widened or a material having high adhesion with the anode body 22 is used, it is difficult to always obtain a stable effect for many production lots. When the groove processing is performed at a predetermined position of the anode body 22 to which the polyimide adhesive tape 25 is attached, the aluminum foil constituting the anode body 22 is crushed around the groove by the groove processing and extends to escape. This elongation is uneven depending on the direction. As a result, residual stress is generated inside the aluminum foil, and the aluminum foil in the grooved portion is twisted and warped. In addition, the production efficiency is lowered, and the quality is adversely affected.
[0007]
The present invention solves such a conventional problem, ensures the insulation between the anode lead portion and the cathode lead portion, stabilizes the quality, does not cause twisting or warping, and has excellent productivity. Another object of the present invention is to provide a method for producing a solid electrolytic capacitor and a solid electrolytic capacitor.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention particularly defines a plurality of through-holes at predetermined positions of a valve-acting metal foil having a surface roughened to form a dielectric oxide film layer. A straight line is provided at intervals, and then a predetermined position including the through-hole is pressed from the front and back surfaces to form a linear groove symmetrically on the front and back surfaces. After producing the separated anode body, and subsequently subjecting the groove portion of the anode body to insulation treatment, a solid electrolyte layer and a cathode layer are sequentially laminated on the surface of the cathode lead portion to form a capacitor element. A cathode lead terminal is connected to the cathode layer of the capacitor element and an anode lead terminal is connected to the anode lead-out portion, and the anode element and a part of the cathode lead terminal are exposed on the outer surface, respectively. This is a method of manufacturing a solid electrolytic capacitor that is covered with an insulating exterior resin. By this method, there is no twisting or warping of the valve action metal foil, and further, groove processing that hardly generates residual stress inside is performed. And having the effect of being able to provide a method of manufacturing a solid electrolytic capacitor with excellent productivity while ensuring the insulation between the anode lead portion and the cathode lead portion to stabilize the quality. .
[0009]
According to a second aspect of the present invention, in the invention according to the first aspect, the insulating 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 a heat resistant silicon. This is done by sticking a heat-resistant tape coated with an adhesive to the groove, and this method has the effect of being able to easily and reliably perform work that requires reliability. Have.
[0010]
The invention according to claim 3 of the present invention is the invention according to claim 1, wherein a continuous strip wound around a reel is used as the valve action metal foil. There is an effect that high work can be performed continuously and efficiently.
[0011]
According to a fourth aspect of the present invention, there is provided a solid electrolytic capacitor manufactured using the manufacturing method according to the first aspect, wherein the anode body is provided in a groove portion that separates the anode lead portion and the cathode lead portion. The structure is such that part of the through hole remains at both ends of the groove portion of the capacitor element, which ensures the insulation between the anode lead portion and the cathode lead portion, thereby improving quality and reliability. It has the effect of being able to provide an excellent solid electrolytic capacitor stably.
[0012]
The invention according to claim 5 of the present invention is the invention according to claim 4, wherein the valve action metal foil is made of one or more of aluminum, tantalum, niobium, zircon, titanium, or an alloy thereof. Accordingly, the operational effect of the invention according to claim 4 can be obtained more efficiently.
[0013]
The invention according to claim 6 of the present invention is the invention according to claim 4, wherein the solid electrolyte layer is a hetero five-membered ring compound and a dielectric thereof, and the dopant is an aryl sulfonic acid or an alkyl phosphate ester. The structure formed by electrolytic oxidation polymerization using at least one of them has the operational effect that the operational effect of the invention of claim 4 can be obtained more efficiently.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the invention according to the first to sixth aspects of the present invention will be described using an embodiment of the present invention.
[0015]
FIG. 1 is a partially cutaway perspective view showing a configuration of a solid electrolytic capacitor according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a capacitor element. The capacitor element 1 is one of valve action metals. A plurality of through-holes 2a are linearly provided at predetermined intervals in a predetermined position of an anode body 2 whose surface is roughened by etching, and a straight line is formed by pressing at a predetermined position including the through-holes 2a. A polyimide adhesive tape 5 is pasted on a groove (not shown) formed in a shape to separate the anode lead portion 3 and the cathode lead portion 4, and the surface of the anode body 2 of the cathode lead portion 4 has a high conductivity. A solid electrolyte layer 6 composed of molecules is formed, and a cathode layer 9 composed of a carbon paint layer 7 and a silver paint layer 8 is sequentially laminated on the solid electrolyte layer 6. It is those who are.
[0016]
Reference numerals 10 and 11 denote an anode lead terminal connected to the anode lead portion 3 and the cathode lead terminal 4 connected to the cathode lead portion 4 of the capacitor element 1 thus configured. Reference numeral 12 denotes the anode lead terminal 10 and the cathode lead terminal. 11 is an insulating exterior resin that covers the capacitor element 1 in a state in which a part of 11 is exposed to the outside.
[0017]
Next, a method for manufacturing the solid electrolytic capacitor of the present embodiment configured as described above will be described. First, as shown in FIGS. 2 (a) and 2 (b), a continuous strip-shaped aluminum foil is etched to form a surface. Is provided with a roughened layer (not shown) and anodized to form a dielectric oxide film layer (not shown) on the surface of the roughened layer. A plurality of through holes 2a are provided in a straight line at predetermined intervals.
[0018]
In the present embodiment, in order to continuously produce a plurality of capacitor elements 1, the through holes 2 a are provided in two straight lines so as to form two rows in the width direction of the anode body 2. It is.
[0019]
Subsequently, as shown in FIGS. 3 (a) and 3 (b), a straight groove 2b is formed on the front and back surfaces by pressing from the front and back surfaces of the anode body 2 into a predetermined position including the through hole 2a provided in the anode body 2. By forming symmetrically, the anode body 2 separated into the anode lead portion 3 and the cathode lead portion 4 with the groove 2b as a boundary is produced.
[0020]
Subsequently, as shown in FIG. 4, an insulating process is performed by sticking a polyimide adhesive tape 5 on the linear groove 2 b provided on the anode body 2, and then a step for obtaining the individual capacitor element 1 is performed. One punching process (punching part 13) is performed.
[0021]
Subsequently, 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. Further, a carbon paint layer 7 and a silver paint layer 8 are formed on the solid electrolyte layer 6. After sequentially forming the cathode layers 9 to be stacked, a punching process (punching part 14) which is one of the steps for obtaining the individual capacitor elements 1 is performed, whereby the capacitor element 1 as shown in FIG. obtain.
[0022]
Thereafter, the cathode lead terminal 11 is connected to the cathode layer 9 of the capacitor element 1 configured as described above, and the anode lead terminal 10 is connected to the anode lead-out portion 3, and one of the anode lead terminal 10 and one of the cathode lead terminals 11 is connected. The capacitor element 1 is covered with an insulating exterior resin 12 in a state where the portions are exposed on the outer surface, respectively, to produce the solid electrolytic capacitor of the present embodiment.
[0023]
The solid electrolytic capacitor according to the present embodiment configured as described above is included in the groove 2b before the predetermined position of the anode body 2 is pressed from the front and back surfaces to form the linear groove 2b symmetrically. By providing a plurality of through-holes 2a in a straight line at regular intervals at a predetermined position, it is possible to provide a portion of the anode body that has been subjected to grooving by grooving that is performed at a predetermined position of the anode body, which has been a conventional problem. Not only can the problem of twisting and warping occur all at once to stabilize production and increase production efficiency, but also as shown in FIG. Since the through-holes 2a provided in a straight line at intervals are located at both ends of the portion separating the anode lead-out portion 3 and the cathode layer 9 of the capacitor element 1, residual stress is generated inside the anode body 2. Less likely to occur and quality Those that can be realized at the same time stabilization.
[0024]
In the present embodiment, pyrrole has been described as the conductive polymer material constituting the solid electrolyte layer 6, but in addition to this, the use of a complex five-membered ring compound such as thiophene has the same effect as pyrrole. Obtainable.
[0025]
Moreover, although aluminum foil was used as an example of the valve action metal foil constituting the anode body 2, any one of tantalum, niobium, zircon, titanium, or a composite or alloy thereof was used. However, an effect equivalent to that of the aluminum foil can be obtained.
[0026]
【The invention's effect】
As described above, the method for manufacturing a solid electrolytic capacitor according to the present invention includes a plurality of through holes that are linearly provided at predetermined intervals in a predetermined position of the valve action metal foil on which the dielectric oxide film layer is formed. Manufacturing of an anode body separated into an anode lead portion and a cathode lead portion with the groove portion as a boundary by pressing a predetermined position from the front and back surfaces of the valve-acting metal foil to form a linear groove portion symmetrically By adopting this method, it is possible to solve the problem of twisting and warping in the anode body of the grooved part at once and to stabilize production and improve production efficiency. In addition, since the through holes provided in the anode body are arranged at both ends of the portion separating the anode lead portion and the cathode layer of the capacitor element, residual stress is hardly generated in the anode body. quality Are those so can be realized at the same time stabilizing, its contribution are those large becomes.
[Brief description of the 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 provided with a through hole for explaining the manufacturing method. (B) Side view (FIG. 3) (a) Plan view of anode body provided with a groove for explaining the manufacturing method (b) Side view (FIG. 4) Insulation treatment for explaining the manufacturing method FIG. 5 is a partially cutaway perspective view showing the structure of the capacitor element. FIG. 6 is a partially cutaway perspective view showing the structure of a conventional solid electrolytic capacitor.
DESCRIPTION OF SYMBOLS 1 Capacitor element 2 Anode body 2a Through hole 2b Groove part 3 Anode lead part 4 Cathode lead part 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)

After roughening the surface of the valve-acting metal foil and forming a dielectric oxide film layer on this surface, a plurality of through holes are provided in a straight line at regular intervals at predetermined positions of the valve-acting metal foil. An anode body separated into an anode lead portion and a cathode lead portion with the groove portion as a boundary by pressing a predetermined position including a through hole from the front and back surfaces of the valve-acting metal foil to form a straight groove portion symmetrically Subsequently, the groove portion of the anode body is subjected to insulation treatment, and then a solid electrolyte layer and a cathode layer are sequentially stacked on the surface of the cathode lead portion to form a capacitor element. The cathode layer of the capacitor element A cathode lead terminal is connected to the anode lead terminal, and an anode lead terminal is connected to the anode lead-out portion, and the capacitor element is insulatively coated with the anode lead terminal and a part of the cathode lead terminal exposed to the outer surface. In the manufacturing method of solid electrolytic capacitor of coating. 2. The insulating 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 performed by attaching a heat-resistant tape coated with a heat-resistant silicon adhesive to the groove portion. The manufacturing method of the solid electrolytic capacitor of description. The manufacturing method of the solid electrolytic capacitor of Claim 1 using the continuous strip | belt-shaped thing wound by the reel as valve action metal foil. A solid electrolytic capacitor manufactured using the manufacturing method according to claim 1, wherein a part of the through hole provided in the groove part separating the anode body into the anode lead part and the cathode lead part is at both ends of the groove part of the capacitor element. Solid electrolytic capacitors that are left in each. The solid electrolytic capacitor according to claim 4, wherein the valve-acting metal foil is made of one or more of aluminum, tantalum, niobium, zircon, and titanium, or an alloy thereof. 5. The solid electrolyte layer according to claim 4, wherein the monomer is a hetero five-membered ring compound and a dielectric thereof, and the dopant is formed by electrolytic oxidation polymerization using at least one of aryl sulfonic acid or alkyl phosphate ester. The solid electrolytic capacitor as described.

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