JPH05291085A - Manufacture of solid electrolytic capacitor - Google Patents

Abstract

PURPOSE:To provide a method of manufacturing a solid electrolytic capacitor, where the solid-state electrolytic capacitor can be easily sealed up with resin and lessened in manufacturing cost and size. CONSTITUTION:A sealing auxiliary plate 4 composed of a lid 26 and a resin reservoir 28 formed as joined to the lid 26 is provided, the opening face of an anode 6 surrounded with a capacity forming part 8 and an upright wall 10 is blocked by the lid 26 of the sealing auxiliary plate 4, sealing resin 38 is filled into the upright wall 10 through the resin reservoir 28 and hardened, and then an excessive sealing resin 38' left inside the resin reservoir 28 is cut off together with the resin reservoir 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a solid electrolytic capacitor using a solid electrolyte such as an organic conductive polymer as an electrolyte.

[0002]

2. Description of the Related Art A solid electrolytic capacitor of this type has been proposed which uses an anode body having a C-shaped cross section by surrounding a capacity forming surface with a standing wall. In the case of using such an anode body, a sealing treatment is performed after a treatment for forming a capacitor element such as a chemical conversion oxide film, a solid electrolyte layer, a conductor layer is performed on the capacitance forming surface. This sealing process is performed using a sealing resin.

By the way, in such a solid electrolytic capacitor, a hybrid integrated circuit is mainly used, and miniaturization and weight reduction are unavoidable in accordance with a demand for miniaturization thereof. For this reason, the anode body, which is a component thereof, is also downsized, and the portion where the sealing resin is injected tends to be miniaturized.

However, since the sealing process with the sealing resin is performed by injection with a dispenser or dipping process, the fluidity of the sealing resin greatly affects the sealing accuracy and the reliability of airtightness, It also affects the yield. In other words, the characteristics and treatment of this sealing resin affect the shape and size reduction of the solid electrolytic capacitor, and may be a factor that hinders the size reduction in some cases. Furthermore, the encapsulating resin also greatly affects the processing cost of the exterior.

Therefore, an object of the present invention is to provide a method of manufacturing a solid electrolytic capacitor which facilitates resin encapsulation, reduces the manufacturing cost and downsizes the product.

[0006]

In the solid electrolytic capacitor of the present invention, a lid portion (26) and a sealing auxiliary plate (4) having a resin reservoir portion (28) continuously formed on the lid portion are formed, The opening surface of the anode body (6) in which the capacity forming portion (8) is surrounded by the standing wall portion (10) with the lid portion of the sealing auxiliary plate is closed, and the sealing resin is filled from the resin reservoir portion into the standing wall portion. (3
8) is filled and the encapsulating resin is cured, and then the excess encapsulating resin (38) that remains inside the resin accumulating portion together with the resin accumulating portion is filled.
´) is separated.

[0007]

[Function] The resin reservoir portion of the auxiliary sealing plate communicates with the portion of the anode body where the sealing resin is to be injected, and is poured from this resin reservoir portion to the portion where the sealing resin is to be injected utilizing the fluidity of the sealing resin. The resin is sealed by the curing. Then, the resin encapsulation part and the surplus encapsulation resin inside the part are separated from the lid part side to complete the resin encapsulation.

The lid portion covering the opening surface of the anode body forms a part of the exterior structure and contributes to maintaining the airtightness of the solid electrolytic capacitor.

[0009]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of a method for manufacturing a solid electrolytic capacitor of the present invention. As shown in FIG. 1A, a sealing auxiliary plate 4 is bonded to the capacitor element 2 as a pretreatment for resin sealing. The capacitor element 2 is formed by an anode body 6 which is a base member. The anode body 6 has standing wall portions 10 formed on three sides of a capacity forming portion 8 having a rectangular flat plate shape, and each standing wall portion 10 forms a capacity. It is a form in which the portion 8 is surrounded. An oxide film layer 12 is formed on the capacitance forming portion 8 by a chemical conversion process after the etching process.
The solid electrolyte layer 14 is formed on the upper surface of 2, and the conductor layer 16 is further formed thereon. Then, an L-shaped anode terminal 18, which is bent along the shape of the anode body 6, is attached to the back surface of the anode body 6 by a fixing means such as welding or adhesion with a conductive adhesive, and the conductor layer 16 is also provided. The conductive adhesive 22 on the upper surface of which the cathode terminal 20 forms a conductor layer
It is fixed with. The cathode terminal 20 has a C-shaped cross section corresponding to the shape or thickness of the anode body 6, and the other end side is fixed to the back side of the anode body 6 with an insulating adhesive 24.

The sealing auxiliary plate 4 is an auxiliary member for assisting the resin sealing and forms a part of the exterior structure. That is, the sealing auxiliary plate 4 is formed by integrally forming the lid portion 26 and the resin reservoir portion 28 that cover the opening face formed by the standing wall portion 10 on the anode body 6, and the boundary portion between the both. A notch portion 30 is formed to separate the two. The resin reservoir 28 is formed with a wall plate 32 covering both side surfaces and a drain portion 34 for draining the surplus sealing resin to the outside. The drain part 34 is formed by bending a part of the auxiliary sealing plate 4 into a V shape, setting its height lower than that of the wall plate 32, and forming an inclined part 36 for guiding the excess sealing resin. Further, the drain portion 34 is set to a height that optimizes the supply amount of the sealing resin to the anode body 6 side, and in the embodiment, it is set slightly lower than the wall plate 32 to seal the wall plate 32 side. Prevents unnecessary flow of resin.

Next, as shown in FIG. 1B, a sealing resin 38 is supplied to the resin reservoir 28 and heated to melt it, and the anode body 6 is sealed by its fluidity. Pour into the space where it should be. By setting the supply amount of the sealing resin 38 to be larger than the volume of the sealing space plus the volume of the resin reservoir 28, the resin sealing can be reliably performed. In this case, 38 'is a surplus sealing resin that does not finally contribute to the sealing.

Next, after the encapsulating resin 38 is cooled and cured, as shown in FIG. 1C, the excess encapsulating resin 38 'is cut off together with the resin reservoir 28 to form a solid electrolytic capacitor as a product. Can be obtained.

Next, a concrete processing method of the method for manufacturing the solid electrolytic capacitor of the present invention will be described with reference to FIGS.

First, as shown in FIG. 2, the anode body 6 is formed using a film-forming metal such as aluminum. The anode body 6 is formed by pressing or cutting, and has a shape in which three sides of the capacity forming portion 8 are surrounded by the standing wall portion 10,
The opening 11 is formed for the convenience of drawing out the cathode terminal 20 and injecting the sealing resin 38. An opening surface surrounded by the standing wall portion 10 is formed on the upper surface of the anode body 6.

Next, as shown in FIG. 3, an oxide film layer 12 is formed on the capacity forming portion 8 of the anode body 6 by etching and then chemical conversion treatment, and a vapor phase is formed on the upper surface of the oxide film layer 12. The solid electrolyte layer 14 made of a polymer film such as polypyrrole is formed by polymerization, chemical polymerization or electrolytic polymerization.
On the upper surface of this solid electrolyte layer 14, a conductive layer 16 is formed with a conductive adhesive to form a substantial cathode. Then, an L-shaped anode terminal 18 is attached to the back surface of the anode body 6,
Further, the cathode terminal 20 is fixed to the upper surface of the conductor layer 16 with a conductive adhesive 22 to complete the capacitor element 2.

Next, as shown in FIG. 4, the sealing auxiliary plate 4 is formed using the same metal material as the anode body 6, for example.
The opening surface of the anode body 6 of the capacitor element 2 is aligned with the lid portion 26 of the sealing auxiliary plate 4, and the both are welded or bonded with an adhesive. At this time, if the junction between the anode body 6 and the lid portion 26 is made tight, the airtightness is strengthened accordingly.

Next, as shown in FIG. 5A, a block-shaped encapsulating resin 38 having an appropriate volume is put in the resin reservoir 28,
In this state, the sealing resin 38 is heated and melted.

Next, as shown in FIG. 5B, when the sealing resin 38 melts, the sealing resin 2 is melted due to its fluidity.
8 flows into the space of the anode body 6 to be sealed with its fluidity, and the surplus sealing resin 38 'remains in the resin reservoir 28 and flows out from the drain 34 to the outside.

Next, after the sealing resin 38 is cooled and hardened, as shown in FIG. 5 (C), shearing is performed on the notch portion 30 which is a portion of the sealing auxiliary plate 4 having low mechanical strength. By applying force, the excess sealing resin 38 is separated from the lid 26 side together with the resin reservoir 28. As a result, the solid electrolytic capacitor as the product shown in FIG. 1C is obtained.

According to such a manufacturing method, the opening surface of the anode body 6 is closed by the sealing auxiliary plate 4 having the lid portion 26 forming a part of the exterior structure, and the sealing auxiliary plate 4 to the anode body 6 is closed. The sealing resin 38 can be injected into the inside of the
In combination with the heating and melting of No. 8, resin injection and sealing can be performed very easily.

Incidentally, in the embodiment, the encapsulating resin 3 having a lump shape is used.
8 was heated and melted to perform resin encapsulation, but the pre-softened encapsulating resin 38 is supplied to the resin reservoir 28 so that the supplementary heat treatment gives proper fluidity to the encapsulating resin 38. You may

[0023]

As described above, according to the present invention,
The following effects can be obtained. a. It is easy to inject the sealing resin into the minute sealing parts,
Along with downsizing of the solid electrolytic capacitor, reliability of resin encapsulation can be improved and manufacturing cost can be reduced. b. By facilitating the injection of the sealing resin, it is not necessary to use a resin supply means such as a high-grade sealing resin supply machine, and the manufacturing cost can be reduced from the viewpoint of manufacturing equipment. c. Various types of sealing resin can be used, from high viscosity to low viscosity, and even when using high viscosity sealing resin, the same resin sealing as when using low viscosity It is possible to improve the reliability of the resin sealing. d. The lid part of the sealing auxiliary plate can be used as part of the exterior structure, and since the lid part covers the opening of the anode body, the airtightness of the solid electrolytic capacitor can be further strengthened, and highly reliable sealing is achieved. The structure can be realized. e. The cost of exterior processing can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a method for manufacturing a solid electrolytic capacitor of the present invention.

2 is a perspective view showing an anode body used in the method for manufacturing the solid electrolytic capacitor shown in FIG. 1. FIG.

3 is a vertical cross-sectional view showing a capacitor element used in the method for manufacturing the solid electrolytic capacitor shown in FIG.

FIG. 4 is a perspective view showing a capacitor element and a sealing auxiliary plate used in the method for manufacturing the solid electrolytic capacitor shown in FIG.

5 is a cross-sectional view showing an intermediate step in the method for manufacturing the solid electrolytic capacitor shown in FIG.

[Explanation of symbols]

 2 Capacitor element 4 Sealing auxiliary plate 6 Anode body 8 Capacitance forming part 10 Standing wall part 26 Lid part 28 Resin reservoir part 38 Sealing resin 38 'Surplus sealing resin

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[Procedure amendment]

[Submission date] April 17, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

[0003]

By the way, in such a solid electrolytic capacitor, a hybrid integrated circuit is mainly used, and miniaturization and weight reduction are unavoidable in accordance with a demand for miniaturization thereof. For this reason, the anode body, which is a component thereof, is also downsized, and the portion where the sealing resin is injected tends to be miniaturized.

Claims (1)

[Claims] 1. An anode body in which a lid portion and a sealing auxiliary plate in which a resin reservoir portion is formed continuously with the lid portion are formed, and the capacity forming portion is surrounded by a standing wall portion with the lid portion of the sealing auxiliary plate. While closing the opening surface of the sealing resin from the resin reservoir into the standing wall and curing the sealing resin, the excess sealing resin remaining inside the resin reservoir along with the resin reservoir is separated. A method of manufacturing a solid electrolytic capacitor, comprising: