JPS6017909A - 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 solid electrolytic capacitor in which a conductive polymer compound obtained by doping a dopant into a finely divided acetylene-based polymer is used as a solid electrolyte.

A solid electrolytic capacitor has a structure in which a solid electrolyte is attached to a film-forming metal such as aluminum or tantalum having an anodized film. Manganese dioxide, which is formed by thermal decomposition of manganese nitrate, is mainly used as the solid electrolyte in conventional solid capacitors of this type. However, due to the high heat required during this thermal decomposition and the oxidizing effect of the NOx gas generated, there is a 11" J scratch on the dielectric metal oxide film such as aluminum or tantalum, which reduces the withstand voltage and There are extremely serious drawbacks such as increased leakage current and deterioration of dielectric properties.Furthermore, step-b of re-formation is required.

In order to compensate for these drawbacks, attempts have been made to form a solid electrolyte layer without applying high heat, that is, to use an organic semiconductor material such as Koden IJ Bamboo as a solid electrolyte. As an example, 7,7,8,8-tetracyanoquinodimethane (TCN
Q) A solid electrolytic capacitor containing a conductive polymer composition containing a complex salt as a solid electrolyte, Nn-propylisoquinoline and 7.7,8.8-tetra described in JP-A-58-17609. I consisting of cyanoquinodimethane
II J7J, solid electrolytic capacitor υ is known.

These TCNQCN compounds have poor f-1 adhesion to the anodized film and insufficient conductivity of 10@-3 to 10@-259 cm@-1, resulting in a small capacitance value and large dielectric loss. Furthermore, the thermal stability over time is also poor, resulting in poor reliability.

The purpose of the present invention is to solve the above-mentioned conventional drawbacks by using an organic 2
An object of the present invention is to provide a solid electrolyte using a 1' conductor as a solid 7U electrolyte.

The present defense is characterized by a solid electrolyte using an acetylene polymer doped with dopanes 1 to 4 having high conductivity as a solid electrolyte, and the solid electrolytic capacitor obtained by the present invention is a conventional solid electrolytic capacitor. Compared to solid electrolytic capacitors using inorganic oxide raw materials or organic semiconductors, it has significantly superior performance in terms of capacity, dielectric loss, and stability over time.

The present invention will be explained in detail below.

The acetylene-based polymer used in the present invention is a ethylene homopolymer or a copolymer of acetylene or substituted acetylene. Typical examples of substituted acetylenes are phenylacetylene and naphthyla 1? Jiren, tc
Examples include r t-butylacetylene.

Since a capacitor is manufactured by entering the boria-di1non-based high polymer into a porous anode metal, it is necessary to be in the form of fine particles, and preferably 1 μm or less. Such polyacetylene-based high polymers can be produced, for example, by using a specific catalyst composition described in Japanese Patent Application No. 18-84145. The acetylene polymers mentioned above are AS F5, BF3, SO
3, +2.811 F5.1-+2 SO4, FeO
By doping an electron acceptor such as E, :+, WCl2, l-1CJ), 04 or Li with an electron donor such as Na, the electrical conductivity increases to 1 or 8~1(Ll
It can be rolled to Con 1 over a wide range up to s, cm-1. In addition, acetinone-based polymers have good adhesion to metals such as TCNQ.
It is better than famous salt.

Therefore, if a conductive ↑)1 high polymer obtained by doping an acetylene-based high polymer with an electron acceptor or an electron donor is used as an electromagnetic material, the following effects can be obtained.

■ Electrolyte layer can be formed without heating the upper part! There is no damage to the oxide film of the l electrode, and there is no need to perform anodic oxidation (reformation) for repair. Therefore, the rated voltage can be increased several times compared to conventional capacitors, and the shape can be made smaller to obtain a capacitor with the same capacity and rated voltage.

3- ■ -B leakage current is small.

■ Capacitors with high withstand voltage can be manufactured.

■ Electrolyte conductivity is 102 to 103 s, co+-1
is sufficiently high that there is no need to install a conductive layer such as graphite. Therefore, the process is simplified, which is advantageous in terms of rice.

An example of a method for producing a solid electrolyte capacitor using a finely divided acetylene polymer doped with an electron acceptor or electron donor as an electrolyte is to use a valve metal such as aluminum or tantalum niobium IeT on which a dielectric film is formed. The adhesion process was carried out two to three times by applying a suspension of fine particles of acetylene polymer or an acetylene polymer doped with an electron acceptor or 17 electrons to the electrode body and drying it. , to form an electrolyte layer.

If an undoped acetylene polymer is used for the electrolyte layer, doping is performed after the deposition process.

The conductivity of the solid electrolyte is 10-1 to 103 s, cn+-
It becomes 1.

Next, take out the cathode with Jζ in the silver paste and case = 4- Place it in a container and seal it with resin.

The present invention will be explained in more detail with reference to Examples below.

Example 1 A high-purity aluminum foil is electrolytically etched to obtain a high surface area magnification and then anodized in a weakly acidic solution to produce an oxidized thin film dielectric.

This aluminum element was doped with an acetylene polymer having an average particle size of 0.3zzm in a FeCJL3-nitromethane solution, and the acetylene polymer was washed with methane. Repeat the steps of applying a gelatinous suspension and drying to form one electrolyte layer, remove the cathode with silver paste, place it in a case, seal it with resin, and solidify]
I created 1no.

Example 2 In Example 1, a solid electrolytic capacitor was created using an acetylene-based high polymer with an average particle size of 0.1 μm doped with BF4 by changing the CfL3-21~romethane solution to a N028F4-nitromethane solution. .

Example 3 A paste-like suspension in which an alleylene-phenylacetylene Jt polymer having an average particle size of 0.2 μm is suspended in 1 heluene is applied to an anodized aluminum element in the same manner as in Example 1, and then dried. This operation was repeated to form an arethy1non-phenylacetylene copolymer layer, and then doping was performed by contacting with iodine vapor to form an electrolyte layer, thereby producing a solid electrolytic capacitor.

Table 1 shows the results of comparing the characteristics of Examples 1 and 2.3 with a conventional solid capacitor using manganese dioxide as an electrolyte (Comparative Example 1) using an anodized aluminum element similar to Example 1. .

Table 1 J: Sea urchin dopant according to the present invention l-
A solid electrolytic capacitor using a fine-grained acetylene-based polymer doped with as an electrolyte has a lower dielectric loss, b4'' than a conventional solid electrolytic capacitor using manganese dioxide as an electrolyte.
It is possible to create solid electrolytic capacitors with low current, high rated voltage, and high withstand voltage. The solid electrolytic capacitor according to the present invention has a larger rated voltage value than that of a solid electrolytic capacitor using manganese dioxide, and a large capacity can be obtained with the same shape.

The metal of the element in Example 1 was aluminum, and the metal of the element was aluminum, but other valve metals such as tantalum and aluminum foil may also be used. Even if the shape is a powder sintered element, One method is not only chemical doping but also electrochemical doping [J', 'C, S.

Chem, C0m1l11. l11.1979594.
C & E N J an, 26°39 (InO2)
; J, C, S, CI) em, CovIlun
,,19B1゜311] Demonii.

Claims (1)

[Claims] A solid electrolytic capacitor characterized in that a solid electrolyte is a conductive polymer compound obtained by doping a dopant into a finely divided 12-1 non-based polymer.