JP2008186881A - Solid electrolytic capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor exhibiting excellent impedance characteristics, electrostatic capacitance and thermal durability among solid electrolytic capacitors using a conductive polymer layer as a solid electrolyte layer. <P>SOLUTION: The solid electrolytic capacitor includes the solid electrolyte layer on a dielectric oxide coat provided on a coat-formed metallic surface. The solid electrolyte layer has at least a conductive polymer layer (A) formed by chemical oxidative polymerization and a conductive polymer layer (B) formed by electrolytic polymerization using the layer (A) as an anode. The layer (B) contains anthraquinone-2-sulfonic acid as a dopant. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a solid electrolytic capacitor using a conductive polymer layer as a solid electrolyte layer.

In recent years, with the digitization of electrical equipment and the speeding up of personal computers, capacitors used in these devices are required to be small and large capacity, to exhibit low impedance in a high frequency range, and to have excellent heat durability. Yes.
In order to meet such demands, solid electrolytic capacitors using a conductive polymer layer having hole conductivity as a solid electrolyte layer have been developed, unlike an electrolytic type capacitor using a conventional electrolytic solution.
Such a solid electrolytic capacitor can cover the inner surface of the pore inside the anode body with a conductive polymer layer having a very high conductivity compared to the liquid electrolyte. In recent years, the amount of its use has greatly increased since it exhibits impedance.
In addition, since the performance of the solid electrolytic capacitor greatly depends on the conductive polymer layer, the development of the conductive polymer used for the conductive polymer layer is one of important issues.
Such a conductive polymer can be obtained by, for example, chemical oxidative polymerization or electrolytic polymerization, but there is a problem that must be solved in order to actually apply the conductive polymer to the solid electrolytic capacitor application. .
Specifically, when the conductive polymer is formed on the dielectric oxide film by chemical oxidative polymerization, a conductive polymer layer having high strength cannot be formed on the dielectric oxide film.
In addition, even if the conductive polymer is formed on the dielectric oxide film by electrolytic polymerization, current cannot flow because the dielectric oxide film is an electrical insulator in the first place. There is a problem that a conductive polymer layer cannot be formed on the dielectric oxide film.

As a means to solve this problem in an integrated manner, a conductive polymer layer is formed on the dielectric oxide film by chemical oxidative polymerization, and a conductive polymer layer is laminated on the conductive polymer layer by electrolytic polymerization. A solid electrolytic capacitor using a double conductive polymer layer as a solid electrolyte has been proposed.
According to this proposal, since the conductive polymer layer formed by chemical oxidative polymerization formed first can pass an electric current, it is possible to perform electropolymerization, and it is possible to form a conductive polymer layer having high strength as a whole. it can.
As a result, a solid electrolytic capacitor having a large electrostatic capacity and excellent electrical characteristics and temperature characteristics can be provided (Patent Document 1).
On the other hand, an aqueous solution of manganese nitrate is brought into contact with the dielectric oxide film, and pyrolytic manganese dioxide is deposited on the dielectric oxide film by thermal decomposition at 250 ° C., and then electropolymerization is performed, whereby anthraquinone-2-sulfonic acid is obtained. A solid electrolytic capacitor in which polypyrrole doped with sodium is formed as a conductive polymer layer has been proposed (Patent Document 2).
A solid electrolytic capacitor in which a conductive polymer layer is formed on a dielectric oxide film by chemical oxidative polymerization has also been proposed. As the conductive polymer layer, polythiophene doped with anthracene sulfonic acid is used in the solid electrolytic capacitor (Patent Document 3).
Japanese Patent Publication No. 4-74853 JP-A-3-34304 JP 2000-12394 A

However, when pyrolytic manganese dioxide is used, the specific resistance of the pyrolytic manganese dioxide is relatively high, and the dielectric oxide film is easily damaged when the pyrolytic manganese dioxide is generated by pyrolysis. For this reason, there are problems such as high impedance and large leakage current.
Further, in the case of a solid electrolytic capacitor in which a conductive polymer layer is formed on a dielectric oxide film by chemical oxidative polymerization and the conductive polymer layer includes polythiophene doped with anthracene sulfonic acid, etc., thermal durability There were problems such as inferior.

  An object of the present invention is to provide a solid electrolytic capacitor exhibiting excellent impedance characteristics, capacitance and thermal durability among solid electrolytic capacitors using a conductive polymer layer as a solid electrolyte layer.

  As a result of intensive studies to solve the above problems, the inventors of the present invention have a conductive polymer layer (A) formed by chemical oxidative polymerization, and a conductive polymer layer (B) formed by electrolytic polymerization. And a solid electrolytic capacitor having at least as a solid electrolyte layer, wherein the conductive polymer layer (B) includes an anthraquinone-2-sulfonic acid as a dopant and is suitable for the purpose of the present invention. The invention has been completed.

That is, the present invention
[1] A solid electrolytic capacitor comprising a solid electrolyte layer on a dielectric oxide film provided on a film-forming metal surface,
The solid electrolyte layer is
A conductive polymer layer (A) formed by chemical oxidative polymerization;
And at least a conductive polymer layer (B) formed by electrolytic polymerization using the conductive polymer layer (A) as an anode,
The conductive polymer layer (B) has the following general formula (1)

（式中、Ｘ^１は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１〜Ｒ_７は、それぞれ独立して水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表される化合物をドーパントとして含むことを特徴とする固体電解コンデンサを提供するものであり、

(In the formula, X ¹ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{1 to} R ₇ are each independently a hydrogen atom or a linear or branched alkyl having 1 to 6 carbon atoms. A solid electrolytic capacitor comprising a compound represented by formula (1) as a dopant:

[2] The compound represented by the general formula (1) is at least one selected from the group consisting of anthraquinone-2-sulfonic acid, anthraquinone-2-sulfonic acid organic ammonium salt, and an anthraquinone-2-sulfonic acid alkali metal salt. The solid electrolytic capacitor as described in [1] above, which is characterized by:

[3] The conductive polymer layer (A) is represented by the following general formula (2)

（式中、Ｘ^２は水素原子またはハロゲン原子を表す。Ｘ^３は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_８〜Ｒ_１１は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２アリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物、
下記一般式（３）

(In the formula, X ² represents a hydrogen atom or a halogen atom. X ³ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{8 to} R ₁₁ are each independently a hydrogen atom, a halogen atom, A linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, A compound having 6 to 12 carbon atoms, a hydroxyl group, a nitro group or a cyano group).
The following general formula (3)

（式中、Ｘ^４、Ｘ^５およびＸ^６はそれぞれ独立して水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒは水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表される化合物、および
下記一般式（４）

(In the formula, X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R represents a hydrogen atom, a linear or branched chain having 1 to 6 carbon atoms. A compound represented by the following formula (4):

（式中、Ｘ^７は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１２〜Ｒ_１８は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２のアリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物からなる群より選ばれる少なくとも一つをドーパントとして含むことを特徴とする、上記［１］または［２］に記載の固体電解コンデンサを提供するものであり、

(In the formula, X ⁷ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{12 to} R ₁₈ are each independently a hydrogen atom, a halogen atom, a linear or branched group having 1 to 6 carbon atoms. A linear alkyl group, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group, The solid electrolytic capacitor according to the above [1] or [2], comprising at least one selected from the group consisting of compounds represented by the following formula: nitro group or cyano group: Is,

[4] The solid electrolysis according to any one of [1] to [3], wherein the conductive polymer layer (A) and the conductive polymer layer (B) each contain polypyrrole. Providing a capacitor,

[5] A step of forming a dielectric oxide film on the film-forming metal surface;
Forming a conductive polymer layer (A) on the dielectric oxide film by chemical oxidative polymerization; and forming a conductive polymer layer (B) on the conductive polymer layer (A) by electrolytic polymerization. Process,
A method for producing a solid electrolytic capacitor having
The electrolytic polymerization is represented by the following general formula (1)

（式中、Ｘ^１は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１〜Ｒ_７は、それぞれ独立して水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表される化合物の存在下に実施されることを特徴とする固体電解コンデンサの製造方法を提供するものであり、

(In the formula, X ¹ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{1 to} R ₇ are each independently a hydrogen atom or a linear or branched alkyl having 1 to 6 carbon atoms. The present invention provides a method for producing a solid electrolytic capacitor, which is carried out in the presence of a compound represented by:

[6] The compound represented by the general formula (1) is at least one selected from the group consisting of anthraquinone-2-sulfonic acid, anthraquinone-2-sulfonic acid organic ammonium salt, and an anthraquinone-2-sulfonic acid alkali metal salt. The method for producing a solid electrolytic capacitor as described in [5] above, characterized in that

[7] The chemical oxidative polymerization is represented by the following general formula (2)

（式中、Ｘ^２は水素原子またはハロゲン原子を表す。Ｘ^３は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_８〜Ｒ_１１は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２アリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物、
下記一般式（３）、

(In the formula, X ² represents a hydrogen atom or a halogen atom. X ³ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{8 to} R ₁₁ are each independently a hydrogen atom, a halogen atom, A linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, A compound having 6 to 12 carbon atoms, a hydroxyl group, a nitro group or a cyano group).
The following general formula (3),

（式中、Ｘ^４、Ｘ^５およびＸ^６はそれぞれ独立して水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒは水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表される化合物、および
下記一般式（４）

(In the formula, X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R represents a hydrogen atom, a linear or branched chain having 1 to 6 carbon atoms. A compound represented by the following formula (4):

（式中、Ｘ^７は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１２〜Ｒ_１８は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２のアリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物からなる群より選ばれる少なくとも一つの存在下に実施されることを特徴とする、上記［５］または［６］に記載の固体電解コンデンサの製造方法を提供するものであり、

(In the formula, X ⁷ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{12 to} R ₁₈ are each independently a hydrogen atom, a halogen atom, a linear or branched group having 1 to 6 carbon atoms. A linear alkyl group, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group, The solid electrolytic capacitor according to the above [5] or [6], which is carried out in the presence of at least one selected from the group consisting of compounds represented by the following formula: Providing a manufacturing method,

[8] An electronic device including the solid electrolytic capacitor according to any one of [1] to [4] is provided.

  According to the present invention, among solid electrolytic capacitors using a conductive polymer layer as a solid electrolyte layer, a solid electrolytic capacitor exhibiting excellent impedance characteristics, capacitance, and thermal durability can be provided.

First, the solid electrolytic capacitor of the present invention will be described.
The solid electrolytic capacitor of the present invention has a dielectric oxide film provided on the surface of a film-forming metal.
Examples of the film-forming metal used in the present invention include aluminum, tantalum, titanium, niobium, zirconium, magnesium, silicon, or one or more of these alloys.

The form of the film-forming metal is preferably a metal foil, a rod, or a sintered body mainly composed of these. More preferably, the surface of the film-forming metal is etched for the purpose of increasing the specific surface area.
The film-forming metal functions as a valve action metal, and a dielectric oxide film can be formed on the surface thereof by electrolytic oxidation, oxidizing agent oxidation, air oxidation or the like.
By performing an etching process on the film-forming metal, fine holes can be formed on the surface of the film-forming metal, and a dielectric oxide film is formed on the surface of the film-forming metal including the inside of the fine holes.

  The solid electrolytic capacitor of the present invention includes a solid electrolyte layer. The solid electrolyte layer includes a conductive polymer layer (A) formed by chemical oxidative polymerization and the conductive polymer layer (A). It has at least a conductive polymer layer (B) formed by electrolytic polymerization as an anode.

Examples of the conductive polymer used in the conductive polymer layers (A) and (B) include polypyrroles such as polypyrrole, poly-3-alkylpyrrole, poly-3,4-alkylenedioxypyrrole, and polyaniline. And polyanilines such as polyalkylaniline, polyfurans such as polyfuran and polyalkylfuran, polythiophenes such as polythiophene, poly-3-alkylthiophene, and poly-3,4-alkylenedioxythiophene.
Among these, polypyrroles are preferable from the viewpoint of price and characteristics, and polypyrrole is more preferable.
The said conductive polymer can use 1 type, or 2 or more types.

The conductive polymer layer (A) used in the present invention is formed by chemical oxidative polymerization on a dielectric oxide film.
Specifically, the conductive polymer layer (A) can be formed by bringing the monomer constituting the conductive polymer described above into contact with an oxidizing agent or the like on the dielectric oxide film. .

  Usually, a monomer solution in which the monomer is dissolved in a solvent is prepared, and the dielectric oxide film formed on the surface of the film-forming metal is impregnated with the monomer solution and then separately prepared. The conductive polymer layer (A) can be formed on the dielectric oxide film by a method such as impregnation with a liquid.

  Examples of the method of impregnating the monomer solution with respect to the dielectric oxide film formed on the surface of the film-forming metal include, for example, impregnating the monomer solution with the film-forming metal itself on which the dielectric oxide film is formed. Examples thereof include a method, a method of spraying the monomer solution onto the dielectric oxide film, and a method of applying the monomer solution onto the dielectric oxide film.

  Further, as a method of impregnating an oxidant solution prepared separately after impregnating the monomer solution, for example, the film-forming metal itself having the dielectric oxide film impregnated with the monomer solution is used as the oxidant solution. Impregnating the dielectric oxide film impregnated with the monomer solution, spraying the oxidant solution onto the dielectric oxide film impregnated with the monomer solution, and applying the oxidant solution to the dielectric oxide film impregnated with the monomer solution. And the like.

  These methods can be carried out singly or in combination of two or more.

Examples of the oxidizing agent include halides such as iodine, bromine, bromine iodide, chlorine dioxide, iodic acid, periodic acid, and chlorous acid, antimony pentafluoride, phosphorus pentachloride, phosphorus pentafluoride, and aluminum chloride. , Metal halides such as molybdenum chloride, permanganate, dichromate, chromic anhydride, ferric salts, cupric salts and other high-valent metal ion salts, sulfuric acid, nitric acid, trifluoromethane sulfuric acid Protonic acids such as oxygen compounds such as sulfur trioxide and nitrogen dioxide, hydrogen peroxide, ammonium persulfate, peroxo acids such as sodium perborate, salts of the peroxo acids, molybdophosphoric acid, tungstophosphoric acid, tungstomolybdoline Examples include heteropolyacids such as acids, salts of the heteropolyacids, and the like.
Among these, it is preferable to use a metal salt (organic metal salt or inorganic metal salt) in a high valence state such as hydrogen peroxide, ammonium persulfate, peroxo acid, peroxo acid salt, ferric salt, or cupric salt. .
The oxidizing agent can be used alone or in combination of two or more.

  The oxidizing agent can be used as an oxidizing agent solution. Examples of the solvent used in the solution include water and alcohol.

Examples of the solvent used for the chemical oxidative polymerization include ether compounds such as tetrahydrofuran (THF), dioxane and diethyl ether, ketone compounds such as acetone and methyl ethyl ketone compounds, dimethylformamide (DMF), acetonitrile and benzonitrile. , N-methylpyrrolidone (NMP), aprotic polar solvents such as dimethyl sulfoxide (DMSO), ester compounds such as ethyl acetate and butyl acetate, non-aromatic chlorine compounds such as chloroform and methylene chloride Nitro compounds such as nitromethane, nitroethane and nitrobenzene, alcohol compounds such as methanol, ethanol and propanol, organic acid compounds such as formic acid, acetic acid and propionic acid, acid anhydrides of the above organic acids (such as acetic anhydride) ), Water, etc. Door can be.
The solvent is preferably water, alcohol compounds, or ketone compounds.
The said solvent can use 1 type, or 2 or more types.

  When the chemical oxidative polymerization is performed, it is preferable to use a compound serving as a dopant. A conductive polymer layer (A) containing a desired dopant can be obtained by chemical oxidative polymerization in the presence of the following compound together with an oxidizing agent.

Examples of the compound serving as the dopant include halogen ions such as iodine, bromine and chlorine, hexafluoroline, hexafluoroarsenic, hexafluoroantimony, tetrafluoroboron, halide ions such as perchloric acid, methanesulfonic acid, Alkyl-substituted organic sulfonate ions such as dodecyl sulfonic acid, cyclic sulfonate ions such as camphor sulfonate ion, alkyl-substituted or unsubstituted such as benzene sulfonic acid, para-toluene sulfonic acid, dodecyl benzene sulfonic acid, benzene disulfonic acid Benzene monosulfonic acid ions, benzenesulfonic acid, paratoluenesulfonic acid, dodecylbenzenesulfonic acid, alkyl-substituted or unsubstituted benzenedisulfonic acid ions such as benzenedisulfonic acid, 2-naphthalenesulfonic acid, 1 7-Naphthalenedisulfonic acid or the like substituted with 1 to 4 sulfonic acid groups, alkyl-substituted or unsubstituted ions of naphthalene sulfonic acid, anthracene sulfonic acid ion, anthraquinone sulfonic acid ion, alkylbiphenyl sulfonic acid, biphenyl disulfonic acid, etc. Substituted or unsubstituted aromatic sulfonate ions such as alkyl-substituted or unsubstituted biphenyl sulfonate ions, polymer sulfonate ions such as polystyrene sulfonate and naphthalene sulfonate formalin condensate, bis-sulcylate boron, Examples thereof include boron compound ions such as biscatecholate boron, and heteropolyacid ions such as molybdophosphoric acid, tungstophosphoric acid, and tungstomolybdophosphoric acid.
The compound used as the dopant can be used alone or in combination of two or more.

  As a preferable compound as the dopant, the following general formula (2)

（式中、Ｘ^２は水素原子またはハロゲン原子を表す。Ｘ^３は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_８〜Ｒ_１１は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２アリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物、
下記一般式（３）

(In the formula, X ² represents a hydrogen atom or a halogen atom. X ³ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{8 to} R ₁₁ are each independently a hydrogen atom, a halogen atom, A linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, A compound having 6 to 12 carbon atoms, a hydroxyl group, a nitro group or a cyano group).
The following general formula (3)

（式中、Ｘ^４、Ｘ^５およびＸ^６はそれぞれ独立して水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒは水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表される化合物、
下記一般式（４）

(In the formula, X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R represents a hydrogen atom, a linear or branched chain having 1 to 6 carbon atoms. A compound represented by the following formula:
The following general formula (4)

（式中、Ｘ^７は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１２〜Ｒ_１８は、それぞれ独立して水素原子、ハロゲン原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基、炭素数１〜６の直鎖状または分岐鎖状アルコキシ基、炭素数１〜６の直鎖状または分岐鎖状ハロゲン化アルキル基、炭素数６〜１２のアリール基、水酸基、ニトロ基またはシアノ基を表わす。）により表される化合物等の一種もしくは二種以上が挙げられる。

(In the formula, X ⁷ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{12 to} R ₁₈ are each independently a hydrogen atom, a halogen atom, a linear or branched group having 1 to 6 carbon atoms. A linear alkyl group, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group, A nitro group or a cyano group.) Or a compound of two or more.

  Examples of the organic ammonium ion include tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, tetrabutylammonium ion, tetrapentylammonium ion, tetrahexylammonium ion, and tetraphenylammonium ion (including various isomers). 1 type or 2 types or more can be mentioned.

  As said metal ion, 1 type, or 2 or more types, such as alkali metals, such as sodium and potassium, alkaline earth metals, such as magnesium and calcium, can be mentioned, for example.

  Examples of the linear or branched alkyl group having 1 to 6 carbon atoms include one or two of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group (including various isomers). The above can be mentioned.

  Examples of the linear or branched alkoxy group having 1 to 6 carbon atoms include a methyloxy group, an ethyloxy group, a propyloxy group, a butyloxy group, a pentyloxy group, and a hexyloxy group (including various isomers). One type or two or more types can be mentioned.

  Examples of the linear or branched alkyl halide group having 1 to 6 carbon atoms include, for example, a fluorinated compound of the linear or branched alkyl group having 1 to 6 carbon atoms, and the above 1 to 6 carbon atoms. Or a chlorinated compound of a linear or branched alkyl group (including various isomers).

  Examples of the aryl group having 6 to 12 carbon atoms include phenyl, methylphenyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, cyclohexylphenyl, dimethylphenyl, di- One or more of propylphenyl group, naphthyl group, biphenyl group and the like (including various isomers) can be mentioned.

Specific examples of the general formula (2) include m-xylene-4-sulfonic acid, mesitylenesulfonic acid, 3-hexyltoluene-4-sulfonic acid, 3,5-dihexyltoluene-4-sulfonic acid, p- Organic sulfonic acids such as toluenesulfonic acid and p-trifluoromethylbenzenesulfonic acid,
An alkali metal salt of the organic sulfonic acid such as a lithium salt of the organic sulfonic acid, a sodium salt of the organic sulfonic acid, or a potassium salt of the organic sulfonic acid;
One or more of the ammonium salts of the organic sulfonic acids can be mentioned.
Examples of the ammonium salts of the organic sulfonic acids include, for example, ammonium salts of the organic sulfonic acids, tetramethylammonium salts of the organic sulfonic acids, tetraethylammonium salts of the organic sulfonic acids, tetrapropylammonium salts of the organic sulfonic acids, Examples thereof include tetrabutylammonium salts of organic sulfonic acids and tetraphenylammonium salts of the organic sulfonic acids.
The general formula (2) is preferably an ammonium salt of the organic sulfonic acid, an alkali metal salt of the organic sulfonic acid, or the like, more preferably tetraethylammonium p-toluenesulfonate or potassium p-trifluoromethylbenzenesulfonate. .

Specific examples of the general formula (3) include sulfophthalic acids such as 4-sulfophthalic acid, 3-methyl-4-sulfophthalic acid, and 3-hexyl-4-sulfophthalic acid,
Sulfoisophthalic acids such as 5-sulfoisophthalic acid, 2-methyl-5-sulfoisophthalic acid, 2-hexyl-5-sulfoisophthalic acid,
Alkali metal salts of the sulfophthalic acids such as lithium salts of the sulfophthalic acids, sodium salts of the sulfophthalic acids, potassium salts of the sulfophthalic acids,
Alkali metal salts of the isosulfophthalic acids such as lithium salts of the isosulfophthalic acids, sodium salts of the isosulfophthalic acids, potassium salts of the isosulfophthalic acids,
One or more of the ammonium salts of the sulfophthalic acids and the ammonium salts of the isosulfophthalic acids can be used.
In the general formula (3), the sulfophthalic acids and ammonium salts of the sulfophthalic acids are preferable, and 4-sulfophthalic acid and triammonium 4-sulfophthalate are more preferable.

Specific examples of the general formula (4) include anthraquinone-2-sulfonic acid, 3-methylanthraquinone-2-sulfonic acid, 6-methylanthraquinone-2-sulfonic acid, and 7-methylanthraquinone-2-sulfonic acid. Anthraquinone-2-sulfonic acids such as 3-hexylanthraquinone-2-sulfonic acid, 6-hexylanthraquinone-2-sulfonic acid, 7-hexylanthraquinone-2-sulfonic acid,
Alkali metal salts of the anthraquinone-2-sulfonic acids such as a lithium salt of the anthraquinone-2-sulfonic acids, a sodium salt of the anthraquinone-2-sulfonic acids, and a potassium salt of the anthraquinone-2-sulfonic acids,
One kind or two or more kinds of ammonium salts of the anthraquinone-2-sulfonic acids can be exemplified.
In the general formula (4), the anthraquinone-2-sulfonic acids, the alkali metal salts of the anthraquinone-2-sulfonic acids, the ammonium salts of the anthraquinone-2-sulfonic acids, and the like are preferable. Anthraquinone-2-sulfonic acid, anthraquinone More preferred are sodium 2-sulfonate and tetraethylammonium anthraquinone-2-sulfonate.

  The dielectric oxide film on which the conductive polymer layer (A) formed by the chemical oxidative polymerization is formed can be subjected to a re-chemical conversion treatment in a chemical conversion solution as necessary.

Next, the conductive polymer layer (B) will be described.
The conductive polymer layer (B) used in the present invention is formed by electrolytic polymerization using the conductive polymer layer (A) as an anode.
Specifically, the conductive polymer layer (B) is formed of the conductive polymer layer (A) in an electrolytic solution containing the monomer, the supporting electrolyte, the solvent, and the like constituting the conductive polymer described above. It can form by implementing electropolymerization as an anode.

The monomer and solvent constituting the conductive polymer used in the electrolytic polymerization are the same as those of the conductive polymer layer (A) described above.
The monomer used for the conductive polymer layer (A) and the monomer used for the conductive polymer layer (B) may be the same or different.

  The supporting electrolyte used in the present invention has the following general formula (1)

（式中、Ｘ^１は水素イオン、アンモニウムイオン、有機アンモニウムイオンまたは金属イオンを表す。Ｒ_１〜Ｒ_７は、それぞれ独立して水素原子、炭素数１〜６の直鎖状または分岐鎖状アルキル基を表わす。）により表されるドーパントとして含むものである。

(In the formula, X ¹ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{1 to} R ₇ are each independently a hydrogen atom or a linear or branched alkyl having 1 to 6 carbon atoms. It represents as a dopant represented by.

Specific examples of the compound represented by the general formula (1) include, for example, methylanthraquinone-2-sulfonic acid, dimethylanthraquinone-2-sulfonic acid, trimethylanthraquinone-2-sulfonic acid, tetramethylanthraquinone-2-sulfone Acid, pentamethylanthraquinone-2-sulfonic acid, hexamethylanthraquinone-2-sulfonic acid, heptamethylanthraquinone-2-sulfonic acid,
Ethyl anthraquinone-2-sulfonic acid, diethyl anthraquinone-2-sulfonic acid, triethylanthraquinone-2-sulfonic acid, tetraethylanthraquinone-2-sulfonic acid, pentaethylanthraquinone-2-sulfonic acid, hexaethylanthraquinone-2-sulfonic acid, Heptaethylanthraquinone-2-sulfonic acid,
Butylanthraquinone-2-sulfonic acid, dibutylanthraquinone-2-sulfonic acid, tributylanthraquinone-2-sulfonic acid, tetrabutylanthraquinone-2-sulfonic acid, pentabutylanthraquinone-2-sulfonic acid, hexabutylanthraquinone-2-sulfonic acid Heptabutylanthraquinone-2-sulfonic acid,
Alkyl-substituted anthraquinone-2-sulfonic acids (including various isomers) such as methylethylanthraquinone-2-sulfonic acid and methylbutylanthraquinone-2-sulfonic acid;
Anthraquinone-2-sulfonic acid,
An ammonium salt of the alkyl-substituted anthraquinone-2-sulfonic acids,
Organic ammonium salts of alkyl-substituted anthraquinone-2-sulfonic acids such as tetramethylammonium salts, tetraethylammonium salts, tetrapropylammonium salts, tetrabutylammonium salts, tetraphenylammonium salts of the alkyl-substituted anthraquinone-2-sulfonic acids,
An ammonium salt of the anthraquinone-2-sulfonic acid,
Organic ammonium salts of anthraquinone-2-sulfonic acids such as tetramethylammonium salt, tetraethylammonium salt, tetrapropylammonium salt, tetrabutylammonium salt, tetraphenylammonium salt of the anthraquinone-2-sulfonic acid,
Alkyl-substituted anthraquinone-2-sulfonic acid alkali metal salts such as sodium salts and potassium salts of the alkyl-substituted anthraquinone-2-sulfonic acids,
Alkyl-substituted anthraquinone-2-sulfonic acid alkaline earth metal salts such as magnesium salts and calcium salts of the alkyl-substituted anthraquinone-2-sulfonic acids,
Anthraquinone-2-sulfonic acid alkali metal salts such as sodium salt and potassium salt of the anthraquinone-2-sulfonic acid,
Anthraquinone-2-sulfonic acid alkaline earth metal salts such as magnesium salt and calcium salt of anthraquinone-2-sulfonic acid can be exemplified.

  The compound represented by the general formula (1) can be used alone or in combination of two or more.

In the compound represented by the general formula (1), R _{1 to} R ₇ are preferably each a hydrogen atom, and anthraquinone-2-sulfonic acid, anthraquinone-2-sulfonic acid organic ammonium salt, and anthraquinone-2-sulfone It is more preferable if it is at least one selected from the group consisting of acid metal salts.
The anthraquinone-2-sulfonic acid organic ammonium salt is more preferably a tetraalkylammonium salt.
The anthraquinone-2-sulfonic acid metal salt is more preferably an alkali metal salt.

  By selecting the supporting electrolyte, a conductive polymer having a specific stable structure is obtained when exposed to a high temperature, and by using the conductive polymer as a solid electrolyte, a heat that is significantly superior to conventional ones is obtained. A solid electrolytic capacitor having durability can be obtained.

In addition to the above, the supporting electrolyte includes lithium salts such as LiPF ₆ , LiAsF ₆ , LiClO ₄ , LiBF ₄ , sodium salts such as NaI, NaPF ₆ , NaClO ₄ , KI, KPF ₆ , KAsF ₆ , KClO _4, etc. One kind or two or more kinds of organic salts such as potassium salt, sodium toluenesulfonate, and tetrabutylammonium toluenesulfonate can be used in combination.

  As the method for the electrolytic polymerization, for example, the conductive polymer layer (A) formed by the chemical oxidation polymerization described above is immersed in the electrolytic solution, and the auxiliary electrode is connected to the conductive polymer layer (A And the like, and a method of performing electropolymerization with an external cathode using the auxiliary electrode as an anode.

  The electrolytic solution used for the electropolymerization includes a monomer that constitutes the conductive polymer, a supporting electrolyte that serves as a dopant, a solvent, and the like. What is contained at a concentration of 01 to 5 mol / L is preferable. Moreover, what contains the supporting electrolyte used as the said dopant by the density | concentration of 0.01-2 mol / L is preferable.

The solid electrolytic capacitor of the present invention can be assembled by a known method.
That is, a conductive polymer layer (A) is formed on the dielectric oxide film by chemical oxidative polymerization, and then the conductive polymer layer (B) is electrolyzed on the conductive polymer layer (A). After forming a solid electrolyte layer by polymerization, a cathode layer is formed by applying and drying a conductive paste such as carbon paste and silver paste on the solid electrolyte layer.

Next, an anode lead terminal is connected from the film forming metal, and a cathode lead terminal is connected from the cathode layer to take out an electrode to form an element. The entire element is made of an insulating resin such as epoxy resin, ceramic, metal, etc. A solid electrolytic capacitor can be obtained by sealing with an outer case or the like.
The solid electrolytic capacitor of the present invention thus obtained can be suitably used for electronic devices such as computers, control devices, communication devices, and home appliances in the electronic / electrical field.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

A 3 mm × 5 mm size etched aluminum formed foil having a dielectric oxide film formed on the surface was dried in a 105 ° C. dryer for 10 minutes. This was left to stand on an 18 ° C. thermoplate for 10 minutes.
Next, 4 μl of a monomer solution (mixture of 3 g of pyrrole, 5 g of ethanol and 18.4 g of water) cooled to 18 ° C. was dropped onto the etched aluminum formed foil, and allowed to stand for 1 minute.
Furthermore, 12 [mu] l of an oxidizing agent solution [mixed solution of 5.6 mmol of paraethylammonium tetraethylammonium (PTS-TEA), 1.56 g of ammonium peroxodisulfate and 10.63 g of water] is dropped on the foil and left to stand for 10 minutes. Thus, a conductive polymer layer (A) formed by chemical oxidative polymerization was formed. This was washed with pure water and dried in a dryer at 105 ° C. for 10 minutes.

  Next, the conductive polymer layer (A) is immersed in an electrolytic solution (mixed solution of 4.67 mmol of anthraquinone-2-sulfonic acid, 0.6 g of pyrrole and 45.8 g of water), and the etched aluminum formed foil Is used as an anode, the current value is fixed at 0.4 mA, and electropolymerization is performed to form a conductive polymer layer (B), whereby a solid is formed on the dielectric oxide film provided on the surface of the etched aluminum formed foil. An electrolyte layer was formed.

Next, a carbon paste and a silver paste were sequentially applied to the conductive polymer layer (B) and dried to complete a total of 20 capacitor elements.
For these 20 capacitor elements, capacitance (Cs) at 120 Hz, loss factor (tan δ × 100), capacitance (Cs) at 100 kHz, and equivalent series resistance (ESR) were measured as initial characteristics.
In addition, a thermal durability test was performed by leaving in the atmosphere at 155 ° C., and the characteristics were evaluated after a predetermined time. The results are shown in Tables 1, 2 and 4 and FIGS.
The capacitor element used in the thermal durability test was not sealed with an insulating resin or the like.

Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of sodium anthraquinone-2-sulfonate, 0.6 g of pyrrole, and 45.8 g of water as the electrolytic solution to form a conductive polymer layer (B).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.

Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of tetraethylammonium anthraquinone-2-sulfonate, 0.6 g of pyrrole, and 45.8 g of water as the electrolytic solution to form a conductive polymer layer (B).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.

Twenty capacitor elements were obtained in the same manner as in Example 2 except that the method for producing the conductive polymer layer (A) was changed to the following method.
That is, chemical oxidation polymerization was performed using a mixed solution of 5.6 mmol of 4-sulfophthalic acid, 1.56 g of ammonium peroxodisulfate, and 10.63 g of water as an oxidant solution to form the conductive polymer layer (A).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.
Compared with Examples 1 to 3, ESR showed a remarkably small value.

Twenty capacitor elements were obtained in the same manner as in Example 2 except that the method for producing the conductive polymer layer (A) was changed to the following method.
That is, chemical oxidative polymerization is performed using 5.6 mmol triammonium 4-sulfophthalate, 1.56 g ammonium peroxodisulfate, 10.63 g water and 3.42 g ethanol as an oxidant solution, and the conductive polymer layer (A) was formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.
Compared with Examples 1 to 3, ESR showed a remarkably small value.

Twenty capacitor elements were obtained in the same manner as in Example 2 except that the method for producing the conductive polymer layer (A) was changed to the following method.
That is, chemical oxidative polymerization was performed using a mixed liquid of 5.6 mmol potassium trifluoromethylbenzenesulfonate, 1.56 g ammonium peroxodisulfate and 10.63 g water as an oxidant liquid, and the conductive polymer layer (A) was formed. Formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.
Compared with Examples 1-3, it confirmed that the electrostatic capacitance Cs increased.

Twenty capacitor elements were obtained in the same manner as in Example 2 except that the method for producing the conductive polymer layer (A) was changed to the following method.
That is, chemical oxidation polymerization was performed using a mixed solution of sodium anthraquinone-2-sulfonate 5.6 mmol, ammonium peroxodisulfate 1.56 g and water 10.63 g as an oxidant solution, and the conductive polymer layer (A) Formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 2 and 4 and FIGS.
Compared with Examples 1-3, it confirmed that the electrostatic capacitance Cs increased.

[Comparative Example 1]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of disodium anthraquinone-2,7-disulfonate, 0.6 g of pyrrole, and 45.8 g of water as an electrolytic solution to form a conductive polymer layer (B). .
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 2]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of naphthalene-2,7-disulfonic acid disodium, 0.6 g of pyrrole and 45.8 g of water as an electrolytic solution to form a conductive polymer layer (B). .
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 3]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of 4,4-biphenyldisulfonic acid, 0.6 g of pyrrole, and 45.8 g of water in the electrolytic polymerization solution to form a conductive polymer layer (B).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 4]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of alkylnaphthalenesulfonic acid Na, 0.6 g of pyrrole and 45.8 g of water as an electrolytic solution to form a conductive polymer layer.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1. The results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 5]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 (mmol) of 4-sulfophthalic acid, 0.9 g of pyrrole, and 45.8 g of water as an electrolytic solution, thereby forming a conductive polymer layer.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1. The results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 6]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of sodium anthraquinone-1-sulfonate, 0.6 g of pyrrole, and 45.8 g of water as the electrolytic solution to form a conductive polymer layer.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1. The results are shown in Tables 1, 3 and 5 and FIGS.
Compared to Examples 1 to 7, the initial characteristics and thermal durability of the capacitors were greatly inferior.

[Comparative Example 7]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of disodium anthraquinone-2,6-disulfonate, 0.6 g of pyrrole and 45.8 g of water as an electrolytic solution to form a conductive polymer layer (B). .
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 8]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of sodium n-dodecylbenzenesulfonate, 0.6 g of pyrrole, and 45.8 g of water as the electrolytic solution to form a conductive polymer layer (B).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 9]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization is performed using a mixed solution of 4.67 mmol of sodium 1,4-naphthoquinone-2-sulfonate, 0.6 g of pyrrole, and 45.8 g of water in the electrolytic solution to form a conductive polymer layer (B). did.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 10]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization is performed using a mixed solution of 3.67 mmol of 3,4-dihydroxyanthraquinone-2-sulfonic acid, 0.6 g of pyrrole and 45.8 g of water in the electrolytic solution to form a conductive polymer layer (B). did.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the result which is largely inferior to thermal durability was shown.

[Comparative Example 11]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of sodium 9,10-dimethoxyanthracene-2-sulfonate, 0.6 g of pyrrole, and 45.8 g of water as the electrolytic solution, and the conductive polymer layer (B) was formed. Formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the rate of change of ESR was particularly large and the results were greatly inferior in thermal durability.

[Comparative Example 12]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of sodium 1-naphthalenesulfonate, 0.6 g of pyrrole, and 45.8 g of water as an electrolytic solution, thereby forming a conductive polymer layer (B).
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the rate of change of ESR was particularly large and the results were greatly inferior in thermal durability.

[Comparative Example 13]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was carried out using a mixed solution of 4.67 mmol of sodium 1-amino-4-bromoanthraquinone-2-sulfonate, 0.6 g of pyrrole and 45.8 g of water as the electrolytic solution, and the conductive polymer layer (B ) Was formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1-7, the rate of change of ESR was particularly large and the results were greatly inferior in thermal durability.

[Comparative Example 14]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of sodium 4,8-diamino-1,5-dihydroxyanthraquinone-2-sulfonate, 0.6 g of pyrrole and 45.8 g of water as the electrolytic solution. A molecular layer (B) was formed.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

[Comparative Example 15]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electropolymerization was performed using a mixed solution of 4.67 mmol of anthraquinone-1,5-disulfonic acid disodium salt, 0.6 g of pyrrole and 45.8 g of water as an electrolytic solution to form a conductive polymer layer (B). .
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

[Comparative Example 16]
Twenty capacitor elements were obtained in the same manner as in Example 1 except that the method for producing the conductive polymer layer (B) was changed to the following method.
That is, electrolytic polymerization was performed using a mixed solution of 4.67 mmol of disodium anthraquinone-1,8-disulfonate, 0.6 g of pyrrole, and 45.8 g of water as an electrolytic solution to form a conductive polymer layer (B). .
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

[Comparative Example 17]
In the case of Example 7, only the conductive polymer layer (A) was formed, and the conductive polymer layer (B) was not formed. A capacitor element was obtained.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

[Comparative Example 18]
In the case of Example 4, only the conductive polymer layer (A) was formed, and the conductive polymer layer (B) was not formed. A capacitor element was obtained.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

[Comparative Example 19]
In the case of Example 1, only the conductive polymer layer (A) was formed, and the conductive polymer layer (B) was not formed. A capacitor element was obtained.
The characteristics of the capacitor element were evaluated in the same manner as in Example 1, and the results are shown in Tables 1, 3 and 5 and FIGS.
Compared with Examples 1 to 7, the results were greatly inferior in thermal durability.

  The solid electrolytic capacitor containing the compound represented by the general formula (1) in the conductive polymer layer (B) is a solid electrolytic capacitor regardless of the type of dopant used in the conductive polymer layer (A). It was confirmed that the heat durability and the like were greatly improved.

上記表２は、実施例におけるコンデンサ素子の耐熱試験において、試験時間に対するＣｓ（１２０Ｈｚ）の変化を示したものである。

Table 2 shows the change in Cs (120 Hz) with respect to the test time in the heat resistance test of the capacitor element in the example.

上記表３は、比較例におけるコンデンサ素子の耐熱試験において、試験時間に対するＣｓ（１２０Ｈｚ）の変化を示したものである。

Table 3 shows the change in Cs (120 Hz) with respect to the test time in the heat resistance test of the capacitor element in the comparative example.

上記表４は、実施例におけるコンデンサ素子の耐熱試験において、試験時間に対するＥＳＲ（１００ｋＨｚ）の変化を示したものである。

Table 4 shows the change in ESR (100 kHz) with respect to the test time in the heat resistance test of the capacitor element in the example.

上記表５は、比較例におけるコンデンサ素子の耐熱試験において、試験時間に
対するＥＳＲ（１００ｋＨｚ）の変化を示したものである。

Table 5 shows the change in ESR (100 kHz) with respect to the test time in the heat resistance test of the capacitor element in the comparative example.

  The capacitor elements produced in Examples 2, 4, 5 and Comparative Examples 1, 4, 6 were subjected to X-ray photoelectron spectroscopy analysis before and after the thermal durability test, and the results are shown in FIGS. 7 to 18 as N1sXPS spectra. The chemical state ratios of N1s are shown in Table 6, and the abundance ratio of nitrogen and sulfur element [the abundance ratio of sulfur element when nitrogen is 1 (relative value)] is shown in Table 7, respectively.

After 110 hours of thermal durability test, in Comparative Examples 1, 4 and 6, the peak intensity ratio near 401.5 eV attributed to —NH ⁺ X ⁻ — in the N1s spectrum decreases, while Examples 2, 4 and 6 5 shows that there is no such change.
The electropolymerized polypyrrole film, which is the conductive polymer layer (B), is doped with anthraquinone-2-sulfonic acid Na and doped with anthraquinone-2,7-disulfonic acid Na and alkylnaphthalenesulfonic acid Na. Compared to the state, it is extremely thermally stable.
That is, a conductive polymer having excellent heat durability is formed.

  Also, from Table 7, sodium anthraquinone-2-sulfonate as a dopant at the time of electrolytic polymerization used in the present invention is different from sodium anthraquinone-1-sulfonate, which is a dopant at the time of electrolytic polymerization that is different only in the position of the sulfone group. This is excellent in that the doping rate into the polypyrrole film is high.

By the way, about the presence state (chemical state, abundance) of the dopant molecule in the conductive polymer, an analysis method by X-ray photoelectron spectroscopy analysis has been reported (reference document Conductive Polymers Vol. 3 p. 134).
X-ray photoelectron spectroscopy is an analytical method in which a sample is irradiated with X-rays in an ultra-high vacuum and the kinetic energy and number of photoelectrons emitted from the inner shell of the atoms constituting the sample are measured with an energy analyzer. is there.

Usually, the electrons that make up an atom are bound to a certain intensity from the nucleus, so the kinetic energy of the photoelectrons emitted when struck with X-rays is
(Excitation light energy)-(Binding energy)
It becomes.
However, a slight change (chemical shift) in the kinetic energy value can be confirmed in comparison with the free state, particularly in a state where the atoms are subjected to other constraints such as forming a compound or a crystal lattice.

  In X-ray photoelectron spectroscopy, the amount of this chemical shift differs depending on the state of the atom where it is placed, so this phenomenon can be used to obtain information on the chemical state of each element. The abundance ratio of various elements can be specified.

When polypyrrole is used as the solid electrolyte of the solid electrolytic capacitor, the peak intensity of the X-ray photoelectron spectroscopy attributed to the chemical state of the solid electrolyte —NH ⁺ X ⁻ — shows a strong correlation with the durability of the capacitor.
That is, before and after the heat resistance test that was left in the atmosphere at 155 ° C. for 110 hours, the decrease rate V of the chemical state —NH ⁺ X ⁻ — in the solid electrolyte defined by the following formula (4) was 0.2 (% / h) or less. It has been found that the solid electrolytic capacitor is extremely excellent in thermal durability.

実際に実施例２、４および５ならびに比較例１および４に関して、耐熱試験前後での化学状態−ＮＨ^＋Ｘ⁻−に帰属される４０１．５ｅＶ付近のピーク強度減少速度、耐熱試験前後での静電容量Ｃｓ（１２０Ｈｚ）減少速度およびＥＳＲ（１００ｋＨｚ）増加速度について表８に結果をまとめた。

Actually, with respect to Examples 2, 4, and 5 and Comparative Examples 1 and 4, the peak intensity decrease rate near 401.5 eV attributed to the chemical state -NH ⁺ X ^-- before and after the heat test, The results are summarized in Table 8 for the rate of decrease in capacitance Cs (120 Hz) and the rate of increase in ESR (100 kHz).

Here, the chemical state -NH ⁺ X ^-- decrease rate, capacitance Cs (120 Hz) decrease rate, and ESR (100 kHz) increase rate are defined by the following equations, respectively.

From Table 8, it was suggested that the decrease rate of the chemical state -NH ⁺ X ^-- before and after the heat resistance test, the capacitance Cs (120 Hz) decrease rate, and the ESR (100 kHz) increase rate are in a proportional relationship.

Further, in Table 8, in Examples 2, 4 and 5 in which sodium anthraquinone-2-sulfonate was used as an electrolytic polymerization dopant, in particular, before and after a heat test at 155 ° C. in the atmosphere for 110 hours, the chemical state —NH ⁺ X ⁻ — When the decrease rate of the capacitance is 0.2 (% / h) or less, the decrease rate of the capacitance Cs (120 Hz) is 0.17 (% / h) or less, and the increase rate of ESR (100 kHz) is 4.0 (% / h). h) The following excellent thermal durability was exhibited.

It is the graph which plotted Cs (120 Hz) with respect to test time in the heat resistance test of the capacitor | condenser element in an Example. It is the graph which plotted Cs (120 Hz) with respect to test time in the heat resistance test of the capacitor | condenser element in a comparative example. It is the graph which plotted Cs (120 Hz) with respect to test time in the heat resistance test of the capacitor | condenser element in a comparative example. It is the graph which plotted ESR (100 kHz) with respect to test time in the heat resistance test of the capacitor | condenser element in an Example. It is the graph which plotted ESR (100 kHz) with respect to test time in the heat resistance test of the capacitor | condenser element in a comparative example. It is the graph which plotted ESR (100 kHz) with respect to test time in the heat resistance test of the capacitor | condenser element in a comparative example. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of Example 2. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat test of the capacitor | condenser element of Example 2. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of Example 4. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat test of the capacitor | condenser element of Example 4. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of Example 5. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat resistance test of the capacitor | condenser element of Example 5. FIG. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of the comparative example 1. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat test of the capacitor | condenser element of the comparative example 1. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of the comparative example 4. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat test of the capacitor | condenser element of the comparative example 4. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis before the heat test of the capacitor | condenser element of the comparative example 6. It is a N1sXPS spectrum figure by the X-ray photoelectron spectroscopy analysis after the heat test of the capacitor | condenser element of the comparative example 6.

Explanation of symbols

1 Peak corresponding to N1s 2 Peak 1 due to influence of dopant
3 Peak 2 due to dopant effects
4 Peak 3 due to dopant effect
5 Peak 4 due to dopant effect

Claims (8)

A solid electrolytic capacitor comprising a solid electrolyte layer on a dielectric oxide film provided on a film-forming metal surface,
The solid electrolyte layer is
A conductive polymer layer (A) formed by chemical oxidative polymerization;
And at least a conductive polymer layer (B) formed by electrolytic polymerization using the conductive polymer layer (A) as an anode,
The conductive polymer layer (B) has the following general formula (1)

(In the formula, X ¹ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{1 to} R ₇ are each independently a hydrogen atom or a linear or branched alkyl having 1 to 6 carbon atoms. A solid electrolytic capacitor comprising a compound represented by the formula:   The compound represented by the general formula (1) is at least one selected from the group consisting of anthraquinone-2-sulfonic acid, anthraquinone-2-sulfonic acid organic ammonium salt, and an anthraquinone-2-sulfonic acid alkali metal salt. The solid electrolytic capacitor according to claim 1, wherein: The conductive polymer layer (A) has the following general formula (2)

(In the formula, X ² represents a hydrogen atom or a halogen atom. X ³ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{8 to} R ₁₁ are each independently a hydrogen atom, a halogen atom, A linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, An aryl group having 6 to 12 carbon atoms, a hydroxyl group, a nitro group or a cyano group).
The following general formula (3)

(In the formula, X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R represents a hydrogen atom, a linear or branched chain having 1 to 6 carbon atoms. A compound represented by the following formula (4):

(In the formula, X ⁷ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{12 to} R ₁₈ each independently represents a hydrogen atom, a halogen atom,
6 linear or branched alkyl groups, linear or branched alkoxy groups having 1 to 6 carbon atoms, linear or branched alkyl halide groups having 1 to 6 carbon atoms, and 6 to 6 carbon atoms 12 aryl groups, a hydroxyl group, a nitro group or a cyano group is represented. The solid electrolytic capacitor according to claim 1, comprising at least one selected from the group consisting of compounds represented by (2) as a dopant. The solid electrolytic capacitor according to claim 1, wherein the conductive polymer layer (A) and the conductive polymer layer (B) each contain polypyrrole. Forming a dielectric oxide film on the film-forming metal surface;
Forming a conductive polymer layer (A) on the dielectric oxide film by chemical oxidative polymerization;
Forming a conductive polymer layer (B) on the conductive polymer layer (A) by electrolytic polymerization;
A method for producing a solid electrolytic capacitor having
The electrolytic polymerization is represented by the following general formula (1)

(In the formula, X ¹ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{1 to} R ₇ are each independently a hydrogen atom or a linear or branched alkyl having 1 to 6 carbon atoms. The method for producing a solid electrolytic capacitor is carried out in the presence of a compound represented by:   The compound represented by the general formula (1) is at least one selected from the group consisting of anthraquinone-2-sulfonic acid, anthraquinone-2-sulfonic acid organic ammonium salt, and an anthraquinone-2-sulfonic acid alkali metal salt. The manufacturing method of the solid electrolytic capacitor of Claim 5 characterized by the above-mentioned. The chemical oxidative polymerization is represented by the following general formula (2)

(In the formula, X ² represents a hydrogen atom or a halogen atom. X ³ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{8 to} R ₁₁ are each independently a hydrogen atom, a halogen atom, A linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkoxy group having 1 to 6 carbon atoms, a linear or branched halogenated alkyl group having 1 to 6 carbon atoms, A compound having 6 to 12 carbon atoms, a hydroxyl group, a nitro group or a cyano group).
The following general formula (3)

(In the formula, X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R represents a hydrogen atom, a linear or branched chain having 1 to 6 carbon atoms. A compound represented by the following formula (4):

(In the formula, X ⁷ represents a hydrogen ion, an ammonium ion, an organic ammonium ion or a metal ion. R _{12 to} R ₁₈ each independently represents a hydrogen atom, a halogen atom,
6 linear or branched alkyl groups, linear or branched alkoxy groups having 1 to 6 carbon atoms, linear or branched alkyl halide groups having 1 to 6 carbon atoms, and 6 to 6 carbon atoms 12 aryl groups, a hydroxyl group, a nitro group or a cyano group is represented. The method is carried out in the presence of at least one selected from the group consisting of compounds represented by:
The manufacturing method of the solid electrolytic capacitor of description.   The electronic device provided with the solid electrolytic capacitor in any one of Claims 1-4.

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