JP2000188238A - Capacitor and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor excellent in capacitor characteristics while decreasing the number of times of polymerization by providing a conductive polymer layer in which polyethylene dioxythiophene and polypyrrole are compounded in at least one dielectric layer. SOLUTION: A polyethylene dioxythiophene layer is formed on the dielectric layer 3 of an aluminum etched foil 1. The thiophene layer is then touched to a pyrrole monomer solution to form a conductive polymer layer where polypyrrole and a polyethylene dioxythiophene layer are compounded through chemical polymerization reaction. Subsequently, it is cleaned and dried and polymerization including a series of processes from immersion coating to drying is repeated until the conductive polymer layer 4 has a specified thickness. Thereafter, a cathode layer 7 is formed on the conductive polymer layer 4, a cathode lead wire 6 is fixed thereto and followed by epoxy resing packaging and aging thus completing a large number of capacitors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a small-sized and large-capacity capacitor having excellent capacitor characteristics, and relates to a conductive material in which polyethylenedioxythiophene and polypyrrole are compounded on at least one surface of a dielectric layer. TECHNICAL FIELD The present invention relates to a capacitor having a conductive polymer layer and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, with the digitization of electric equipment,
As for the capacitor, a capacitor having a small size, a large capacity, and a low impedance in a high frequency region is required.

Hitherto, many capacitors have been proposed in which a conductive polymer having high electric conductivity is used as the electrolyte of the capacitor to reduce the impedance in a high frequency range.

[0004] 3, 4 on aluminum with a dielectric coating
P-ethylenedioxythiophene as a repeating unit
A capacitor in which a conductive polymer containing a toluenesulfonic acid anion as a dopant is formed by chemical polymerization has been proposed (JP-A-2-15611).

A solution obtained by dissolving 3,4-ethylenedioxythiophene monomer and an oxidizing agent in a solvent is applied to an oxidized aluminum electrode, and then the solvent is removed at room temperature or by heating. A manufacturing method is described in which a conductive polymer layer is formed, the excess oxidizing agent is washed away from the conductive polymer layer with water, and finally dried to obtain a capacitor.

[0006] A capacitor element in which a mixed solution of 3,4-ethylenedioxythiophene and an oxidizing agent is wound around a separator made of glass paper on an anode electrode foil and a cathode electrode foil. A solid electrolytic capacitor has been proposed in which polyethylenedioxythiophene formed by a chemical polymerization reaction in a mixed solution impregnated in a separator and held by a separator is used as an electrolyte layer (Japanese Patent Application Laid-Open No. 9-1990).
-293639).

[0007] Using ferric p-toluenesulfonate as an oxidizing agent and ethylene glycol as a solvent, the capacitor element impregnated with the mixed solution is allowed to stand at a temperature of 25 ° C to 100 ° C for chemical polymerization. A production method is described in which a conductive polymer layer made of polyethylenedioxythiophene is formed by a reaction, washed with water, an organic solvent, and the like, and finally dried to obtain a capacitor.

Further, a large-capacity film capacitor has been proposed, in which a dielectric made of an electrodeposited polyimide thin film is formed on an etched aluminum foil, and then a conductive polymer layer is sequentially formed by chemical polymerization and electrolytic polymerization to form an electrode. (The 58th Annual Meeting of the Institute of Electrical Chemistry, Abstracts, pp. 251-252 (1991)
Year)).

[0009]

However, a mixed solution in which 3,4-ethylenedioxythiophene monomer and an oxidizing agent are dissolved in a solvent is applied or impregnated to the capacitor element, and the evaporation of the solvent and the chemical polymerization reaction are simultaneously carried out. In the manufacturing method in which the conductive polymer layer is formed by proceeding, an excess oxidizing agent remains in the formed conductive polymer layer.

If the excess oxidizing agent is not sufficiently removed by washing, the capacity is reduced and the loss, impedance and leakage current increase when exposed to high temperature and high humidity, and the characteristics are deteriorated. Must be removed by washing.

When the excess oxidizing agent is removed by washing, a cavity is formed in a portion where the oxidizing agent is removed, and a dense conductive polymer layer cannot be obtained. There is a problem that excellent capacitor characteristics such as low impedance in the region cannot be obtained.
Further, in order to obtain a certain degree of capacitor characteristics, there is a problem that the number of times of polymerization increases.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a solid electrolytic capacitor having excellent capacitor characteristics and to provide a manufacturing method capable of reducing the number of times of polymerization.

[0013]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems. In the capacitor of the present invention, polyethylenedioxythiophene and polypyrrole are compounded on at least one of the dielectric layers. This is a configuration including a conductive polymer layer.

Further, a method of manufacturing a capacitor according to the present invention comprises:
A step of preparing a mixed solution of 3,4-ethylenedioxythiophene monomer and an oxidizing agent dissolved in a solvent, a step of preparing a dielectric layer, and applying the mixed solution to at least one of the dielectric layers Forming a polyethylenedioxythiophene layer on at least one of the dielectric layers by a chemical polymerization reaction between the 3,4-ethylenedioxythiophene monomer and the oxidizing agent; Or a pyrrole monomer mixed with a solvent
A step of preparing a solution, contacting the pyrrole monomer solution with the polyethylene dioxythiophene layer, formed by a chemical polymerization reaction between the oxidizing agent and the pyrrole monomer in the polyethylene dioxythiophene layer. Forming a conductive polymer layer in which polypyrrole and the polyethylene dioxythiophene layer are combined.

According to the present invention, a mixed solution obtained by dissolving a 3,4-ethylenedioxythiophene monomer and an oxidizing agent in a solvent is applied to at least one of the dielectric layers to form a 3,4-ethylenedioxythiophene monomer. After a polyethylene dioxythiophene layer is formed on at least one of the dielectric layers by a chemical polymerization reaction between the polyethylene dioxythiophene layer and the oxidizing agent, a pyrrole monomer solution is brought into contact with the polyethylene dioxythiophene layer.
(Pyrrol monomer has the ability to dissolve the oxidizing agent in the same manner as the organic solvent.) Dissolution of the oxidizing agent in the polyethylene dioxythiophene layer and chemical polymerization of the dissolved oxidizing agent with the pyrrole monomer The reaction is allowed to proceed simultaneously to form polypyrrole, and a conductive polymer layer in which the polyethylenedioxythiophene layer and the polypyrrol are combined is formed.

Polypyrrole is formed at or near the site of the oxidizing agent in the polyethylene dioxythiophene layer, and a dense conductive polymer layer in which the polyethylene dioxythiophene layer and the polypyrrol are complexed can be obtained. Therefore, a capacitor having excellent capacitor characteristics such as a high capacity achievement rate, a low loss, and a low impedance in a high frequency region can be obtained with a small number of polymerizations.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION
The capacitor comprises a conductive polymer layer in which polyethylene dioxythiophene and polypyrrole are compounded on at least one of the dielectric layers.

In a capacitor in which the dielectric layer is composed of a valve metal oxide film, the conductive polymer layer functions as an electrolyte which also functions as a cathode, while in a film capacitor in which it is composed of a polymer thin film, a simple structure is used. Functions as an electrode.

The invention according to claim 2 of the present invention is characterized in that
A step of preparing a mixed solution in which ethylenedioxythiophene monomer and an oxidizing agent are dissolved by a solvent; a step of preparing a dielectric layer; and applying the mixed solution to at least one of the dielectric layers. Forming a polyethylenedioxythiophene layer on at least one of the dielectric layers by a chemical polymerization reaction of 1,4-ethylenedioxythiophene monomer and the oxidizing agent; Preparing a mixed pyrrole monomer solution, contacting the pyrrole monomer solution with the polyethylene dioxythiophene layer, and contacting the oxidizing agent in the polyethylene dioxythiophene layer with the pyrrole monomer solution;
Forming a conductive polymer layer in which polypyrrol formed by a chemical polymerization reaction with a monomer and a polyethylenedioxythiophene layer are combined, and a method for manufacturing a capacitor, A mixed solution of 3,4-ethylenedioxythiophene monomer and an oxidizing agent dissolved in a solvent is applied to at least one of the dielectric layers,
After a polyethylenedioxythiophene layer is formed on at least one of the dielectric layers by a chemical polymerization reaction of 3,4-ethylenedioxythiophene monomer and an oxidizing agent, a pyrrole monomer solution is added to the polyethylenedioxythiophene layer. And the dissolution of the oxidizing agent in the polyethylenedioxythiophene layer and the chemical polymerization reaction proceed simultaneously to form polypyrrol, and the conductive polymer layer in which the polyethylenedioxythiophene layer and the polypyrrol are combined. To form

Polypyrrole is formed at or near the site of the oxidizing agent in the polyethylene dioxythiophene layer, and a dense conductive polymer layer in which the polyethylene dioxythiophene layer and polypyrrol are complexed is obtained. Therefore, a capacitor having excellent capacitor characteristics such as a high capacity achievement ratio, a low loss, and a low impedance in a high frequency region can be realized with a small number of polymerizations.

Here, examples of the oxidizing agent include ferric alkylbenzenesulfonate, ferric naphthalenesulfonate, ferric alkylnaphthalenesulfonate, ferric anthraquinonesulfonate, and mixtures thereof. Preferably, ferric naphthalene sulfonate is used.

The solvent used for the mixed solution includes water, methanol, ethanol, isopropanol, butanol.
And mixtures thereof, but ethanol is preferably used.

The step of applying the mixed solution includes:
Examples include brush coating, dip coating, drop coating, spray coating and the like, and preferably dip coating can be used.

The solvent for the pyrrole monomer solution includes:
Examples thereof include water, methanol, ethanol, isopropanol, butanol, and a mixture thereof. Ethanol is preferably used.

Further, as described in claim 3, the dielectric layer may be an oxide of a valve metal. Further, aluminum can be used as the valve metal.

Further, the dielectric layer may be constituted by a polymer film.

Further, the polymer film can be constituted by a polyimide film.

Hereinafter, embodiments of the present invention will be described in detail. (Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIG.

The aluminum-etched foil 1 having a length of 8 mm and a width of 3.3 mm is partitioned into 4 mm and 3 mm portions.
A polyimide tape 2 having a width of 1 mm was stuck on both sides.

Next, 3 mm of the aluminum-etched foil 1
Attach the anode lead wire 5 to the × 3.3 mm portion, and attach the 4 mm × 3.3 mm portion of the aluminum etched foil 1 to the
Using a 3% aqueous solution of ammonium adipate at 70 ° C., the voltage was first raised from 0 to 10 V at a rate of 10 mV / sec, then a constant voltage of 10 V was applied for 40 minutes, and the dielectric layer 3 was formed by anodic oxidation. After washing with running deionized water for 10 minutes, drying was performed at 105 ° C. for 5 minutes.
This configuration was regarded as a capacitor, and the capacity in the chemical conversion solution was measured to be 18 μF.

A ferric naphthalene sulfonate solution was prepared by dissolving an oxidizing agent comprising a transition metal salt of ferric naphthalene sulfonate in 5.2% by weight of water and 57.65% by weight of ethanol as a solvent. . Next, 7.5 g of ethanol as a solvent was used.
Was mixed with 3 g of the ferric naphthalenesulfonate solution. Further, 3,4-ethylenedioxythiophene monomer-0.2 which is a thiophene derivative monomer
After mixing 4 g, the mixture was stirred to prepare a mixed solution.

Aluminum etched foil 1 in the mixed solution
The part provided with the dielectric layer 3 was immersed for 1 minute, pulled up, placed in an oven at 120 ° C., and left for 20 minutes.
The solvent was quickly evaporated by heating, and the chemical polymerization reaction proceeded to form a polyethylenedioxythiophene layer on the dielectric layer 3.

Next, a 50% by weight pyrrole monomer solution was prepared using ethanol as a solvent. The portion of the aluminum-etched foil 1 provided with the polyethylene dioxythiophene layer was immersed in the pyrrole monomer solution, and left for 15 minutes in a state where the pyrrole monomer solution was in contact with the polyethylene dioxythiophene layer. . By the chemical polymerization reaction between the oxidizing agent in the polyethylene dioxythiophene layer and the pyrrole monomer, polypyrrol is formed at or near the oxidizing agent site, and the polypyrrol and the polyethylene dioxythiophene layer are combined. The conductive polymer layer 4 was formed.

Next, the aluminum-etched foil 1 was immersed in ethanol of an organic solvent for 10 minutes for cleaning. Then, put 10 pieces of aluminum-etched foil 1 in deionized water.
The substrate was immersed for a minute to wash. Then, it was placed in an oven and dried at 105 ° C. for 5 minutes.

Until the conductive polymer layer 4 has a predetermined thickness, the number of times of polymerization, which is a series of steps from dip coating to drying, is repeated 10 times.

After the formation of the conductive polymer layer 4, the cathode layer 7 is formed thereon with a carbon layer and a silver paint layer.
A cathode lead wire 6 was mounted thereon.

Further, after packaging using an epoxy resin, aging treatment was performed to complete a total of 10 capacitors.

For these 10 capacitors, 1k
The capacity at Hz, the loss factor, and the impedance at 400 kHz were each measured. The average values are shown in the following (Table 1).

[0039]

[Table 1]

According to the present embodiment, after a polyethylene dioxythiophene layer is formed on a dielectric layer, a pyrrole monomer solution is brought into contact with the polyethylene dioxythiophene layer to oxidize the polyethylene dioxythiophene layer. The dissolution of the agent and the chemical polymerization reaction proceed simultaneously to make polypyro-
To form a conductive polymer layer in which the polyethylene dioxythiophene layer and the polypyrrol are combined. Polypyrrole is formed at or near the site of the oxidizing agent in the polyethylene dioxythiophene layer, and a dense conductive polymer layer in which the polyethylene dioxythiophene layer and polypyrrol are complexed is obtained, As shown in Table 1, it is possible to obtain a capacitor having excellent capacitor characteristics such as a high capacity achievement ratio, a low loss, and a low impedance in a high frequency region.

(Comparative Example 1) As Comparative Example 1, after forming a polyethylenedioxythiophene layer, a pyrrole monomer solution was brought into contact with the polypyrrole and the polyethylenedioxythiophene layer without being subjected to a complexing treatment.
A capacitor was manufactured in the same manner as in Embodiment 1, except that the polyethylene dioxythiophene layer was changed to a conductive polymer layer.

The results of measuring the characteristics are shown in the above (Table 1). In Comparative Example 1, since the oxidizing agent in the polyethylenedioxythiophene layer was removed by washing with an organic solvent and deionized water, a cavity was formed, so that it was difficult to obtain a dense conductive polymer layer. Therefore, as shown in Table 1, it was found that excellent capacitor characteristics could not be obtained.

(Comparative Example 2) As Comparative Example 2, after forming a polyethylene dioxythiophene layer, a pyrrole monomer solution was brought into contact with the polypyrrole and the polyethylene dioxythiophene layer without being subjected to a treatment to form a composite.
A capacitor was manufactured in the same manner as in Embodiment 1, except that the polyethylene dioxythiophene layer was used as a conductive polymer layer and the number of polymerizations was changed to 15 times.

The results of measuring the characteristics are shown in the above (Table 1). In Comparative Example 2, since the oxidizing agent in the polyethylene dioxythiophene layer was removed by washing with an organic solvent and deionized water, a cavity was formed, so that it was difficult to obtain a dense conductive polymer layer. Therefore, even if the number of times of polymerization is increased, as shown in Table 1, the capacitor characteristics of the present invention are lower than those obtained by compounding the conductive polymer layer with the polyethylene dioxythiophene layer and polypyrrole. It turned out to be inaccessible.

As is clear from the comparison between Comparative Examples 1 and 2 in Table 1 and Embodiment 1, in Embodiment 1, the polyethylene dioxythiophene layer and polypyrrol were combined. Since a dense conductive polymer layer was obtained, it was found that a capacitor having excellent capacitor characteristics such as a high capacity achievement rate, a low loss, and a low impedance in a high frequency region was obtained with a small number of polymerizations. did.

(Embodiment 2) Instead of forming a dielectric layer composed of an oxide film on an aluminum foil of 20 mm × 20 mm as in Embodiment 1, a 0.5 μm thick polyimide thin film is formed by spin coating. Then, a total of ten capacitors were manufactured under the same conditions as in the first embodiment except that a dielectric layer made of the polyimide thin film was formed. The same characteristic evaluation as in the first embodiment was performed, and the average values thereof are shown in (Table 1).

The capacity obtained here was 91% in capacity achievement rate. According to the present embodiment, after forming the polyethylene dioxythiophene layer on the dielectric layer,
Pyrolemonomer in the polyethylenedioxythiophene layer
A conductive polymer in which the solution is brought into contact, the dissolution of the oxidizing agent in the polyethylene dioxythiophene layer and the chemical polymerization reaction proceed simultaneously to form polypyrrol, and the polyethylenedioxythiophene layer and the polypyrrol are complexed. Form a layer. Polypyrrole is formed at or near the site of the oxidizing agent in the polyethylene dioxythiophene layer, and a dense conductive polymer layer in which the polyethylene dioxythiophene layer and polypyrrol are complexed is obtained, With a small number of polymerizations, as shown in (Table 1), a high capacity achievement rate,
A capacitor having excellent capacitor characteristics such as low loss and low impedance in a high frequency region can be obtained.

(Embodiment 3) Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

As the anode electrode foil 11, an aluminum-etched foil 12 provided with a dielectric layer 13 on both sides by anodic oxidation was used after being cut into a size of 2.3 mm in width and 154 mm in length. The cathode electrode foil 14 has a width of 2.
An aluminum etched foil having a length of 3 mm and a length of 180 mm was used.

Next, the anode electrode foil 11 and the cathode electrode foil 14
Is wound via a separator 15 made of manila paper having a thickness of 40 μm and stopped by a stop tape 16 to obtain a capacitor element 17. The external dimensions of the wound capacitor element 17 used here were about 7 mm in diameter,
The distance between the end faces 8 and the lower end face 19 is 3.4 mm. In addition, the anode electrode foil 11 and the cathode electrode foil 14
An anode lead wire 20 and a cathode lead wire 21 are electrically connected in advance, and protrude from the upper end face 18.

Next, the cut surface when the anode electrode foil 11 was formed was anodized. The capacitor element 17 was immersed in a 3% aqueous solution of ammonium adipate at 70 ° C. while supporting the anode lead wire 20. First 10mV / s
The voltage was increased from 0 to 14 V at a speed of ec, and a constant voltage of 14 V was continuously applied for 10 minutes, and a dielectric layer was formed on the cut surface by anodic oxidation. After washing with running deionized water for 10 minutes, drying was performed at 105 ° C. for 5 minutes. This configuration was regarded as a capacitor, and the capacity in the chemical conversion solution was 220 μF.

A ferric naphthalene sulfonate solution was prepared by dissolving an oxidizing agent comprising a transition metal salt of ferric naphthalene sulfonate in 5.2% by weight of water and 57.65% by weight of ethanol as a solvent. . Further, a ferric triisopropylnaphthalenesulfonate solution in which an oxidizing agent comprising a transition metal salt of ferric triisopropylnaphthalenesulfonate was dissolved at 60% by weight of ethanol was prepared. Next, 0.96 g of the ferric naphthalenesulfonate solution and 2.55 g of the ferric triisopropylnaphthalenesulfonate solution were added to 6.45 g of ethanol and mixed. Further, 3,4-ethylenedioxythiophene monomer-0.
After mixing 22 g, the mixture was stirred to prepare a mixed solution.

The capacitor element 17 was immersed in the mixed solution for 2 minutes to be impregnated, pulled up, placed in an oven at 130 ° C., and left for 20 minutes. The solvent quickly evaporates due to the heating, the chemical polymerization reaction proceeds, and the capacitor element 17
, A polyethylene dioxythiophene layer was formed.

Next, a pyrrole monomer not diluted with a solvent
A solution was prepared. The capacitor element 17 is immersed in the pyrrole monomer solution, and the capacitor element 17 is contacted with the polyethylene dioxythiophene layer.
Left for 0 minutes. By the chemical polymerization reaction between the oxidizing agent in the polyethylene dioxythiophene layer and the pyrrole monomer, polypyrrol is formed at or near the oxidizing agent site, and the polypyrrol and the polyethylene dioxythiophene layer are combined. The conductive polymer layer 22 was formed.

Next, the capacitor element 17 was immersed in ethanol of an organic solvent for 15 minutes for cleaning. Subsequently, the capacitor element 17 was immersed in deionized water for 15 minutes to perform cleaning. Then, place in an oven at 120 ° C for 3 hours.
Dried for 0 minutes.

The conductive polymer layer 22 serves as the capacitor element 17
The number of times of polymerization, which is a series of steps from dip coating to drying, was repeated eight times until a predetermined amount was formed in the inside.

After the formation of the conductive polymer layer 22, the capacitor element 17 is housed in a bottomed cylindrical aluminum case, and the opening is closed with an epoxy resin. Completed 10 capacitors.

For these ten capacitors, 1k
The capacity at Hz, the loss factor, and the impedance at 400 kHz were each measured. The average values are shown in (Table 1).

According to the present embodiment, after the polyethylene dioxythiophene layer is formed inside the capacitor element, the polyethylene dioxythiophene layer is brought into contact with a pyrrole monomer solution, and the oxidizing agent in the polyethylene dioxythiophene layer is contacted. Dissolution and chemical polymerization reaction proceed simultaneously to form polypyrrole, and form a conductive polymer layer in which the polyethylenedioxythiophene layer and polypyrrole are complexed. Polypyrrole is formed at or near the site of the oxidizing agent in the polyethylene dioxythiophene layer, and a dense conductive polymer layer in which the polyethylene dioxythiophene layer and polypyrrol are complexed is obtained,
As shown in Table 1, it is possible to obtain a capacitor having excellent capacitor characteristics such as a high capacity achievement ratio, a low loss, and a low impedance in a high frequency region.

(Comparative Example 3) As Comparative Example 3, after forming a polyethylenedioxythiophene layer, a pyrrole monomer solution was brought into contact with the polypyrrole and the polyethylenedioxythiophene layer was not treated to form a composite.
A capacitor was manufactured in the same manner as in Embodiment 3, except that the polyethylene dioxythiophene layer was changed to a conductive polymer layer.

The results of measuring the characteristics are shown in the above (Table 1). In Comparative Example 3, since the oxidizing agent in the polyethylene dioxythiophene layer was removed by washing with an organic solvent and deionized water, a cavity was formed, so that it was difficult to obtain a dense conductive polymer layer. Therefore, as shown in Table 1, it was found that excellent capacitor characteristics could not be obtained.

As is clear from the comparison between Comparative Example 3 and Embodiment 3 in (Table 1), in Embodiment 3,
In order to obtain a dense conductive polymer layer in which the polyethylene dioxythiophene layer and polypyrrol are complexed,
It was found that a capacitor having excellent capacitor characteristics such as a high capacity achievement ratio, a low loss, and a low impedance in a high frequency region was obtained with a small number of polymerizations.

In the second embodiment, a case has been described in which polyimide is used as a polymer to be a dielectric layer. However, any polymer material other than polyimide can be used as long as it is a polymer material capable of forming a thin film. The invention is not limited to that type. Also, the case where a polyimide thin film to be a dielectric layer is formed on an aluminum foil by spin coating has been described. It can be applied, and the present invention is not limited to the forming method.

In the embodiment, a polymerizable monomer is used.
Has been described only for the case where 3,4-ethylenedioxythiophene is used, but derivatives having other substituents can also be used.

In the above embodiment, only the case where the valve metal is aluminum has been described, but other materials such as tantalum, zirconium, niobium, hafnium and titanium, and intermetallic compounds thereof can also be used.

[0066]

As described above, according to the present invention, a dense conductive polymer layer in which polyethylene dioxythiophene and polypyrrol are complexed can be obtained. An advantageous effect is obtained in that a capacitor having excellent capacitor characteristics such as efficiency, low loss, and low impedance in a high frequency region can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view and a sectional view of a capacitor according to a first embodiment of the present invention.

FIG. 2 is an external view and an enlarged internal view of a capacitor element according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 12 Aluminum etched foil 2 Polyimide tape 3, 13 Dielectric layer 4, 22 Conductive polymer layer 5, 20 Anode lead wire 6, 21 Cathode lead wire 7 Cathode layer 11 Anode electrode foil 14 Cathode electrode foil 15 Separator 16 Unwinding tape 17 Capacitor element 18 Upper end face 19 Lower end face

Claims (6)

[Claims] 1. A capacitor comprising a conductive polymer layer in which polyethylene dioxythiophene and polypyrrole are compounded on at least one of the dielectric layers. 2. A step of preparing a mixed solution in which 3,4-ethylenedioxythiophene monomer and an oxidizing agent are dissolved by a solvent; a step of preparing a dielectric layer; and at least one of the dielectric layers. Applying the mixed solution, the 3,4-ethylenedioxythiophene monomer
Forming a polyethylene dioxythiophene layer on at least one of the dielectric layers by a chemical polymerization reaction between the polymer and the oxidizing agent; and preparing a pyrrole monomer itself or a pyrrole monomer solution mixed with a solvent. Contacting the pyrrole monomer solution with the polyethylene dioxythiophene layer, and forming polypyrrol by a chemical polymerization reaction between the oxidizing agent and the pyrrole monomer in the polyethylene dioxythiophene layer. And forming a conductive polymer layer in which the polyethylene dioxythiophene layer is composited. 3. The capacitor according to claim 1, wherein the dielectric layer is an oxide of a valve metal. 4. The valve metal according to claim 1, wherein the valve metal is aluminum.
The capacitor as described. 5. The capacitor according to claim 1, wherein the dielectric layer is a polymer film. 6. The polymer film according to claim 4, wherein the polymer film is a polyimide film.
The capacitor as described.