JPS6193611A - Manufacture of solid electrolytic capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a solid electrolytic capacitor, and in particular a method for forming a flat capacitor element using a metal film that can improve the strength of the anode lead against the capacitor element. It is related to.

[Prior art] -This type of solid electrolytic capacitor is, for example, the Utility Model Act of 1973-
As disclosed in Japanese Patent No. 12885, a metal wire having a valve action is planted in advance as an anode lead in a capacitor element made by press-molding and sintering metal powder having a valve action into a flat rectangular shape. , a first external lead member is welded to the anode lead, and a second external lead member is soldered to the electrode lead layer formed on the circumferential surface of the capacitor element via an oxide layer and a semiconductor layer, and the capacitor The entire circumferential surface of the element is covered with a resin material.

According to this capacitor, for example, Utility Model Application No. 51-7894
As disclosed in Publication No. 7, the exterior form of the capacitor element can be made much thinner than that of a capacitor element having a cylindrical shape, so it meets the recent demands for lightness, thinness, shortness, and smallness. For example, it is widely used in fields such as calculators, cameras, and watches.

[Problems to be solved by the invention] By the way, in this capacitor, the anode lead planted on the capacitor element has an extremely thin covering thickness with metal powder due to the flattening of the capacitor element, so the strength of the planting is also low. There is a problem in that leakage current characteristics are impaired due to dropout or rattling during the manufacturing process.

However, although the planting strength can be improved to some extent by increasing the compressed density of the metal powder, the CV value (capacitance x voltage) of the capacitor element will be extremely reduced, making it impossible to obtain the desired capacitor characteristics. Therefore, the pressurized density cannot be increased unnecessarily. For this reason, the problem of the planting strength of the anode lead still remains as an issue to be solved.

Therefore, an object of the present invention is to provide a method for manufacturing a solid electrolytic capacitor that can improve the strength of the anode lead against the capacitor element by using a metal film having a valve action to an extent that does not pose a practical problem.

[Means for solving the problem] Therefore, in order to achieve the above-mentioned object, the present invention includes a step of applying a metal powder that induces a valve action to a metal film having a valve action, and a step of applying a metal powder that causes a valve action to a metal film that has a valve action. a step of connecting a metal wire having the structure as an anode lead, a step of winding a metal film around the anode lead, a step of crushing the wound body of the metal film into a flat shape, a step of adhering the metal powder to the metal film, and/or Alternatively, the method includes a step of sintering the rolled body after the step of crushing it.

[Function] According to this invention, since the anode lead is connected to the metal film by welding or the like, it is possible to ensure sufficient planting strength to prevent flat dust from forming on the capacitor element. This eliminates all troubles caused by the characteristics.

Moreover, since the capacitor element is constructed by crushing a rolled body of metal film, flat dust can be set appropriately. For this reason, it is possible to appropriately meet the needs of light, thin, short, and small.

[Embodiment] Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

First, as shown in Figure 1, tantalum and niobium.

For example, the same metal powder 2 is uniformly applied to a metal film 1 such as aluminum that has a valve effect. This deposition may be done by using plasma spraying, or by using metal powder,
A mixed member consisting of a binder and a solvent can also be applied by spraying, screen printing, or the like. Then, this metal film 1 is sintered in a vacuum, and the metal powder 2 is
is fused to the metal film 1. Next, as shown in FIG. 2, the metal film 1 is cut into a predetermined length, and
A metal wire having a valve action at its end is welded as the anode lead 3. Note that this anode lead 3 is made of metal film 1. Preferably, it is the same metal as the metal powder 2. Next, as shown in FIG. 3, the metal film 1 is wound around the anode lead 3. Next, as shown in FIG. 4, the capacitor element 4 is formed by crushing the rolled metal film 1 into a flat shape and sintering it. Next, as shown in FIG. 5, an electrode lead layer 5 is formed on the circumferential surface of the capacitor element 1 by an ordinary method via an oxide layer, a semiconductor layer, and a graphite layer. Then, the first external lead member 6 is connected to the anode lead 3 and the second external lead member 7 is connected to the electrode lead layer 5, and the entire circumferential surface of the capacitor element 4 is covered with a resin material 8 by molding. A solid electrolytic capacitor is obtained.

Note that the sintering operation can also be performed only after the rolled body is crushed.

[Effects of the Invention] As described above, according to the present invention, since the anode lead is connected to the metal film by welding or the like, sufficient planting strength can be obtained regardless of flat dust caused by crushing of the wound body. , and any problems caused by this in terms of characteristics can be completely eliminated.

Moreover, the capacitor element is constructed by crushing a wound body of metal film, and since the thickness of the metal film is extremely thin, the flattening of the wound body by crushing can be done without increasing the pressing force too much. , can be easily achieved.

[Brief explanation of the drawing]

The figures are explanatory views of the method of the present invention, in which Fig. 1 is a plan view showing the state of adhesion of metal powder to the metal film, Fig. 2 is a plan view showing the state of connection of the anode lead to the metal film, and Fig. 2 is a plan view showing the state of connection of the anode lead to the metal film. 3
FIG. 4 is a perspective view showing a rolled state of the metal film, FIG. 4 is a perspective view showing the rolled body in a collapsed state, and FIG. 5 is a front view showing the completed state. In the figure, 1 is a metal film, 2 is a metal powder, 3 is an anode lead, and 4 is a capacitor element.

Claims (3)

[Claims] (1) A step of applying a metal powder having a valve action to a metal film having a valve action, a step of connecting a metal wire having a valve action to the metal film as an anode lead, and a step of winding the metal film around the anode lead. , a step of crushing a rolled body of metal film into a flat shape, and a step of sintering after a step of adhering metal powder to the metal film and/or a step of crushing the rolled body. Method of manufacturing electrolytic capacitors. (2) The method for manufacturing a solid electrolytic capacitor according to claim 1, wherein the metal film, metal powder, and anode lead are made of the same metal. (3) A method for manufacturing a solid electrolytic capacitor according to claims 1 or 2, characterized in that the anode lead is connected to the metal film by welding.