JPS59117210A - 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.

Conventionally, solid electrolytic capacitors using a valve metal such as tantalum as an anode body have been manufactured by immersing the anode body in a solution or melt of manganese nitrate, etc., and then heating the anode body to an appropriate temperature to form a semiconductor layer such as manganese dioxide. Thermal decomposition method is used. However, with this method, N generated during thermal decomposition
Because of the Ox scum, the semiconductor layer does not become a homogeneous, uniformly thin layer, but becomes porous and has poor adhesiveness. Therefore, there was a drawback that the resistance of the semiconductor +*a itself and the contact resistance with the carbon layer provided on the semiconductor layer were increased, and the loss of the capacitor was increased.

It is well known that when IC1 pyrolysis is carried out in a steam atmosphere, a homogeneous and uniform thin layer is formed.
The temperature exceeds 30'C, and as a result, the lead wire of tantalum, etc. drawn out from the anode body is exposed to sparks when welding the wire and terminal to the anode body. It is dangerous to fly, makes work difficult, and generally increases leakage current.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a solid electrolytic capacitor that is easy to operate and that can improve loss and leakage current characteristics by overcoming the above-mentioned drawbacks.

In order to achieve the above object, the present invention provides a solid state in which a sintered body after an anodic oxide film is formed is immersed in a semiconductor mother liquor, and then thermally decomposed in a steam atmosphere of 200°C or less to form a semiconductor layer. The present invention provides a method for manufacturing an electrolytic capacitor.

In addition, in order to achieve the above object, the present invention provides that after immersing the sintered body after forming the anodic oxide film in a semiconductor mother liquor to which a reducing agent such as ammonium nitrate, urea, formic acid, and alcohols has been added, The present invention provides a method for manufacturing a solid electrolytic capacitor, characterized in that a semiconductor layer is formed by thermal decomposition in a steam atmosphere at a temperature of 200° C. or lower.

Furthermore, in order to achieve the above object, the present invention provides that the sintered body after forming the anodic oxide film is immersed in a liquid; The present invention provides a method for manufacturing a solid electrolytic capacitor, characterized in that a semiconductor layer is formed by thermal decomposition in a steam atmosphere at a temperature of 200° C. or lower.

That is, according to the present invention, the thermal decomposition temperature is 200° C. or lower, which is in the low temperature range, so that the semiconductor liquid such as mankanite nitrate does not splash when decomposed, and therefore, The subsequent welding of the terminal becomes easier, and since a homogeneous and uniform thin semiconductor layer is formed, loss is improved and leakage current characteristics are further improved.

d3, the reducing agent promotes thermal decomposition, and the working efficiency jr<A.

Next, let's talk about the embodiments of the present invention.

Example 1 Tantalum was used as the valve metal, and a sintered body made of tantalum powder was crushed in a phosphoric acid aqueous solution and heated to 140
An anodic oxide film is formed by performing oxidation at a voltage of V1.

After forming the anodic oxide film, the sintered tube was impregnated with an aqueous solution of 40-60% mankanite nitrate with 0 addition of ammonium and thermally decomposed in a steam atmosphere at 180"C, and this process was completed. Repeat 5 to 7 times to form a mankane dioxide layer.After forming the mankane dioxide layer, as usual,
Carbon layer (11! Metal layer of best layer and solder layer is provided to produce Kuntal solid wood electrolytic content.

The tantalum solid electrolytic capacitor of the present invention with a rating of 35 V and 10 μF thus produced was impregnated with a conventional reducing agent-free manganese nitrate solution and thermally decomposed at 250°C in a steam atmosphere. The initial characteristics of 100 pieces of each were measured and the results shown in Table 1 were obtained. As a result, Table 1 shows that the present invention has a loss of about 13% and a leakage current of about 7%.
This is a 9% reduction, and it is clear that both loss and leakage current characteristics have been improved.

Example 2゜ In addition, a rated 16
When the initial characteristics of tantalum solid electrolytic capacitors of V10 μF according to the present invention and those of the conventional example were measured, the results shown in Table 2 were obtained.

Table 2 In other words, according to the present invention, the loss is reduced by about 8%, and the leakage current is reduced by about 80%.

As described above, according to the present invention, a solid electrolytic capacitor that not only facilitates terminal welding work but also has significantly improved loss and leakage current characteristics is provided.

Special applicant: Nichizu Capacitor Co., Ltd.

Claims (3)

[Claims] (1) In the manufacturing method of solid electrolytic capacitors, an anodized film, a semiconductor layer, a carbon layer, and a metal layer are sequentially formed on a sintered body made of valve metal powder. A method for producing a solid electrolytic capacitor, which comprises immersing it in a semiconductor mother liquor and then thermally decomposing it in a steam atmosphere at 200°C or lower to form a semiconductor layer. (2) In a method for manufacturing a solid electrolytic capacitor in which an anodic oxide film, a semiconductor layer, a sword-bond layer, and a metal layer are sequentially provided on a sintered body made of valve metal powder, sintering after the anodic oxide film is formed. A solid electrolytic capacitor characterized in that a solid electrolytic capacitor is immersed in a semiconductor mother liquor to which a reducing agent such as ammonium nitrate, urea, formic acid, and alcohols has been added, and then thermally decomposed in a steam atmosphere at 200°C or less to form a semiconductor layer. manufacturing method. (3) In a method for producing a solid electrolytic capacitor in which an anodized film, a semiconductor layer, a carbon layer, and a metal layer are sequentially provided on a sintered body made of valve metal powder, the sintered body after the anodic oxide film is formed is mixed with a semiconductor mother liquor. ammonium nitrate, after soaking in
200℃ containing reducing agents such as urea, formic acid and alcohols
A method for manufacturing a solid electrolytic capacitor, characterized by forming a semiconductor layer by thermal decomposition in the following steam atmosphere.