JPS59155116A - Method of producing solid electrolytic condenser - 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 The present invention relates to a method for manufacturing a solid electrolytic capacitor, and particularly to a method for leading out and packaging a cathode lead of a resin-sealed solid electrolytic capacitor element.

Conventionally, in the manufacturing method of solid electrolytic capacitors, as shown in Fig. 1, an anode lead 3, in which an anode body 2 made of a valve metal is protruded from the anode body 2, is attached to a band-shaped conductive plate 1 made of aluminum or the like by welding or the like. After suspending the body and anodizing it in a chemical conversion tank (not shown) to form a dielectric layer on the surface of the anode body 2,
- Depositing a semiconductor layer such as manquan dioxide and a cathode conductive layer consisting of a carbon layer and a silver-based layer to form the capacitor element 5; Next, as shown in FIG. 2, after the anode lead 3 and the anode external lead 4 are connected by welding or the like, the anode lead 3 is cut and the anode lead 3 connected to the conductive plate 1 is removed.

Next, as shown in FIG. 3, after inserting a cathode lead 7 and a chip-shaped solder 8 into a metal case 6 such as aluminum, a capacitor element 5 is inserted, and the solder inside the case 6 is heated. 8 is melted to connect the cathode conductive layer on the outer periphery of the capacitor element 5 and the cathode lead 7 via 80 layers of solder. Next, as shown in FIG. 4, a resin 9 such as liquid epoxy is injected and filled into the upper layer of the capacitor element 5 to which the cathode lead 7 is connected inside the case 6, and after 7'C, it is heated and hardened. It formed a solid electrolytic capacitor.

Such conventional methods for manufacturing solid electrolytic capacitors have the following drawbacks.

(a) Since the cathode lead attachment and resin sealing processes are separated, the process becomes long and productivity is poor.

(b) In the process of resin sealing, it takes a long time to fill the resin and then harden it, resulting in poor workability.

(c) Since the pot life of the resin used is short, there is a lot of resin wasted.

(d) The workability of injection and filling is poor because liquid resin is used.

An object of the present invention is to provide a method for manufacturing a solid electrolytic capacitor that eliminates such conventional drawbacks.

According to the present invention, a dielectric layer is formed on an anode body made of a valve metal with a protruding anode lead, and after fC, a semiconductor layer and a cathode conductive layer are sequentially formed on the surface of the dielectric layer, and an anode external layer is formed on the anode lead. The process of connecting the leads to form a capacitor element, the process of inserting the capacitor element and the cathode lead wire in parallel into the case, the process of filling the peripheral part of the capacitor element with solder material, and the process of filling the case with solder material. A method for manufacturing a solid electrolytic capacitor is obtained, which includes a step of filling the upper layer of the solder material with powdered resin, and a step of heating the case to melt the solder material and melt/solidify the powdered resin.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 2 and 5 to 7.

An anode IJ-de 3 made of a tantalum metal wire is suspended by welding or the like, and an anode body 2 made of a molded body of tantalum metal powder is protruded from the anode body 2 on a band-shaped conductive plate l such as an aluminum plate shown in Fig. 1. After forming a dielectric layer (not shown) on the surface of the anode body 2 by anodizing in a dielectric layer forming chemical bath (not shown), a semiconductor layer (not shown) such as mankan dioxide is applied to the surface.
Then, a cathode conductive layer (not shown) consisting of a carbon layer and a silver paste layer is formed. Next, as shown in FIG. 2, the anode lead 3 and the tip 4a of the anode external lead 4, whose tip is bent into an L-shape and which is hung at equal intervals from another band plate lO such as cardboard, are welded. After fc, the anode lead 3 is cut at the upper part of the connection position and the anode lead 3 connected to the conductor 11 plate 1 is removed.

Next, as shown in FIG. 5, the capacitor element 5 and the cathode lead 7 are brought into parallel contact with each other in a case 16 made of, for example, a brass plate whose surface is plated with solder. Insert it so as to surround the capacitor element 5. Next, as shown in FIG. 6, the case 6 is set in a resin molding auxiliary jig 11 made of a releasable material such as silicone rubber and provided with holes, and the solder layer 18 filled in the case 6 is Fill the upper part of the epoxy resin (D powdered thermosetting adhesive 9).

Next, since the filled powdered resin 19 does not penetrate into the solder/@18, the case 16 is passed through a constant temperature drying oven heated to a temperature at which the solder 18 melts and the solder 18 and resin 19 are removed.
After being melted and solidified in a state where it is separated into two layers (the resin 19 is in a pre-cured state but solidified), the melting temperature of the solder 18 is 80°C to 200°C, which is lower than the melting temperature of 190°C to 250°C.
When the resin 19 is completely cured by heating at .degree. C., a solid electrolytic capacitor as shown in FIG. 7 is obtained. In addition, the case that houses the capacitor element is made of a material that does not adhere to solder, such as aluminum, and the capacitor element, cathode lead, solder material, and powdered resin are inserted and filled so that the case has heat resistance that does not allow solder to adhere. Of course, heating may be performed by immersing it in molten solder while holding it using a molding auxiliary jig made of a material.

As described above, the present invention has the following effects.

(1) Cathode lead attachment and resin sealing process for solid electrolytic capacitors (can be carried out as one continuous process in a short time without separating the steps until the resin solidifies).

(11) Because it uses a powdered resin with a long bottle life, it has excellent productivity, with less restrictions on working time and no wastage of materials.

[Brief explanation of drawings]

1 to 54 are side views showing the manufacturing process of a conventional solid electrolytic capacitor. 5 to 7 are side sectional views of the manufacturing process according to the present invention. 1... Conductor'ii: plate, 2... Anode body,
3...Anode lead, 4...Anode external lead, 5...Capacitor element, 6.16...
...Case, 7...Cathode lead, 8°18.
...Solder, 9. '19...Resin, 10.
... Band plate, ]l ... Forming auxiliary jig.

Claims (1)

[Claims] After forming a dielectric layer on an anode body made of valve metal with an anode lead protruding thereon, a step of sequentially forming a semiconductor layer and a cathode conductive layer on the surface thereof, and connecting an anode external lead to the anode lead, forming a capacitor element;
A step of inserting the capacitor element and the cathode lead wire almost parallel into the case, a step of filling the periphery of the capacitor element with solder material, and a step of filling the upper layer of the solder material of the case with powdered resin. and a step of heating the case to melt the solder material and melt and solidify the powdered resin.