JP4070004B2 - Electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel electrolytic capacitor which is excellent in impedance characteristic, leakage current characteristic and reliability, and has a high breakdown voltage. SOLUTION: The electrolytic capacitor uses an electrolyte containing a conductive polymer (A) and an organic acid onium salt (B). The electrolytic capacitor is preferably of a solid type and more preferably uses organic acid onium salt which follows. That is, the organic acid onium salt contains onium and organic acid anions; the onium cation is one or more selected from the cation group of consisting of quaternary ammonium, tertiary sulfonium, quaternary phosphonium and tertiary oxonium; and the organic acid anion one or more selected from the group of anions obtained by removing protons from organic acids of carboxylic acid, phenols, mono- or di-phosphoric acid ester and boron complex.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrolytic capacitor, and more particularly to a novel electrolytic capacitor using a conductive polymer (A) and an organic acid onium salt (B).
[0002]
[Prior art]
In recent years, with the digitization of electronic devices and the like, a capacitor having a small size, a large capacity, and a low impedance in a high frequency region is required. Conventionally, there are a plastic film capacitor and a multilayer ceramic capacitor as a capacitor for a high frequency region, but these capacitors are large in shape and difficult to increase in capacity. On the other hand, as a large capacity capacitor, there is an aluminum dry electrolytic capacitor or an aluminum or tantalum solid electrolytic capacitor. These electrolytic capacitors require an anode serving as a valve action metal, an anodic oxide film (dielectric) formed on the anode surface, and an electrolyte serving as a true cathode. For example, in an aluminum dry electrolytic capacitor, an etched anode and cathode aluminum foil are wound up via a separator, and a driving electrolyte is impregnated in the separator.
[0003]
However, the aluminum dry electrolytic capacitor has a serious problem of characteristic deterioration due to electrolyte leakage, evaporation and the like. Since the liquid electrolyte has ionic conductivity and a large specific resistance, there is a problem that the loss is large and the frequency characteristics of the impedance are extremely inferior. In order to improve these problems, the solidified electrolyte is an aluminum or tantalum solid electrolytic capacitor. Examples of the electrolyte of the solid electrolytic capacitor include manganese oxide, 7,7,8,8-tetracyanoquinodimethane (TCNQ) salt, and conductive polymers such as polypyrrole, polythiophene, and polyaniline.
[0004]
[Problems to be solved by the invention]
However, solid electrolytic capacitors using manganese oxide as an electrolyte can improve the temperature characteristics, capacity, loss, and other issues over time, but manganese oxide has a high specific resistance and sufficient frequency characteristics of impedance. It can not be said. Further, when forming an electrolyte made of manganese oxide, the dielectric oxide film is damaged by a plurality of thermal decomposition treatments. In addition, a solid electrolytic capacitor using a TCNQ salt as an electrolyte has a problem that a specific resistance increases when TCNQ is applied, and adhesion to an anode foil is weak.
[0005]
On the other hand, in the method of forming a conductive polymer on the surface by chemical oxidative polymerization from monomers such as pyrrole, thiophene, or aniline, the influence of deterioration of the dielectric oxide film by the oxidizing agent or the chemical property of the conductive polymer (dielectric) It is difficult to construct an electrolytic capacitor with a rated voltage exceeding 35V because there is almost no defect in the body oxide film), and even when these capacitors are constructed, they will leak during the aging process and high temperature test. In some cases, an increase in current or a short circuit between the anode and the cathode occurred.
[0006]
An object of the present invention is to solve such problems and to provide an electrolytic capacitor having a high withstand voltage that is excellent in impedance characteristics, leakage current characteristics, and reliability.
[0007]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have found that an electrolytic capacitor using an electrolyte composed of a conductive polymer (A) and an organic acid onium salt (B) has impedance characteristics, leakage current characteristics, It has been found that an electrolytic capacitor having excellent reliability and high withstand voltage can be obtained. That is, the present inventionIt is a compound obtained by doping a conjugated double bond polymer (A-1) with an aliphatic sulfonic acid having 1 to 30 carbon atoms and an aromatic sulfonic acid having 7 to 30 carbon atoms.Organic acid onium salt in which conductive polymer (A) and onium cation are imidazolinium having 3 to 30 or more carbon atoms, imidazolium having 3 to 30 or more carbon atoms, and organic acid anion is sulfonate anion (B)Contains no solventA solid electrolytic capacitor using an electrolyte.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the conductive polymer (A) is a conjugated double bond polymer (A-1) or a compound obtained by doping the polymer with a dopant (A-2). (A-1) is a polymer of one or more monomers (a-1) forming a conjugated double bond polymer. (A) is whether (A-2) is doped after polymerization of (a-1) or at the time of polymerization, preferably (A-2) is doped during polymerization of (a-1). More preferably, (A-2) is added during the polymerization of (a-1) to carry out the polymerization. (A-2) added at the time of polymerization may be an oxidizing agent (a-2). In this case, (a-2) participates in the polymerization as an oxidizing agent and simultaneously acts as a dopant.
[0009]
Examples of (a-1) include the following compounds (1) to (4) having 2 to 30 or more carbon atoms.
(1) Aliphatic triple bond compounds; acetylene, 1,6-heptadiyne and the like;
(2) Aromatic conjugated compounds; benzene, naphthalene, anthracene, etc .;
(3) Heteroatom-containing conjugated compounds; heterocyclic compounds such as pyrrole, thiophene, furan, and ethylenedioxythiophene; non-heterocyclic compounds such as aniline, sulfonated aniline, and diphenyl sulfide.
(4) A compound in which an alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, lauryl, stearyl group, etc.), an aryl group (phenyl, naphthyl group, etc.) or the like is substituted.
One or two or more of these monomers (a-1) may be used. Of these, the heteroatom-containing conjugated compound (3) is preferable, and more preferable are a heterocyclic compound and aniline, and particularly preferable are pyrrole, thiophene, ethylenedioxythiophene, and aniline.
[0010]
Examples of the oxidizing agent (a-2) include the following compounds (1) to (7).
(1) Transition metal salt; inorganic acid salt (iron sulfate, iron nitrate, iron chloride, iron perchlorate, iron phosphate, iron bromide, iron hydroxide, copper nitrate, copper sulfate, copper chloride, etc.); organic acid Salts [oxalates (iron oxalate, copper oxalate, etc.), aliphatic iron sulfonates having 1 to 30 carbon atoms (iron methanesulfonate, iron propanesulfonate, etc.), aromatic sulfonic acids having 7 to 30 carbon atoms Iron (iron sulfonate sulfonate, iron p-toluenesulfonate, etc.), C1-C30 aliphatic sulfonate copper (methane sulfonate copper, propane sulfonate copper, etc.), C7-30 aromatic sulfonic acid Copper (copper benzoate, copper phthalate, etc.); complex salts (sodium dichromate, potassium dichromate, ammonium dichromate, sodium permanganate, potassium permanganate, sodium phosphomolybdate, etc.);
(2) Protic acid and its salts [excluding transition metal salt of (1)]; hydrochloric acid, sulfuric acid, nitric acid, fluorosulfuric acid, chlorosulfuric acid, hydrofluoric acid, phosphohydrofluoric acid and the like, and alkali metals of the protic acid (Sodium, potassium, etc.) salts, ammonium salts, organic amines having 3 to 10 carbon atoms (trimethylamine, triethylamine, etc.), etc.
(3) Diazonium salt; benzene diazonium hydrogen sulfate, o-toluene diazonium hydrogen sulfate, and the like.
(4) Halogen and halides: bromine, iodine, bromine iodide, arsenic pentafluoride, antimony pentafluoride, silicon tetrafluoride, phosphorus pentachloride, phosphorus pentafluoride, aluminum chloride, aluminum bromide and the like.
(5) Peracids and salts thereof; hydrogen peroxide, inorganic peracids (perchloric acid, periodic acid, etc.); organic peracids (peracetic acid, perbenzoic acid, etc.); and alkali metals of the above peracids (sodium, Potassium etc.) salts, ammonium salts, organic amines having 3 to 10 carbon atoms (trimethylamine, triethylamine etc.) and the like.
(6) Quinones; benzoquinone, naphthoquinone, etc.
(7) Other oxidizing agents; sulfur trioxide, nitrogen dioxide, ozone, etc.
Of these, preferred are transition metal salts, protonic acids and salts thereof, more preferred are sulfonic acid transition metal salts, iron chloride, hydrochloric acid and sulfuric acid, and particularly preferred are aliphatic sulfone having 1 to 30 carbon atoms. It is iron acid, C7-30 aromatic iron sulfonate, iron chloride, and sulfuric acid. In addition, (a-2) may use 1 type, or 2 or more types.
[0011]
Examples of the method for forming (A) or (A-1) include the following methods (I) to (III) in which (a-1) and preferably (a-2) are added and reacted.
(I) Method by liquid phase chemical polymerization In the case of the polymerization, the capacitor element is immersed in a solution containing (a-1) to perform oxidative polymerization. In this case, it is preferable to add an oxidizing agent (a-2). In this case, the viscosity and concentration may be adjusted by adding a solvent. The polymerization solvent used in the polymerization may be a known solvent such as water, monoalcohol (methanol, ethanol, propanol, isopropanol, etc.), glycol (ethylene glycol, diethylene glycol, triethylene glycol, tripropylene glycol, etc.), Monoether (methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, Tetrahydrofuran, etc.), diethers (ethylene glycol dimethyl ether, ethylene glycol diethyl ether) Ter, diethylene glycol ethyl methyl ether, diglyme, triglyme, tetraethylene glycol dimethyl ether, 1,3-dioxane, etc.), nitrile (acetonitrile, benzonitrile, etc.), ketone (acetone, methyl ethyl ketone, etc.), amide (dimethylformamide, dimethylacetamide, etc.) , Carbonates (ethylene carbonate, propylene carbonate, etc.), esters (ethyl acetate, diethyl maleate, etc.), lactones (γ-butyrolactone, δ-valerolactone, etc.), sulfur-containing solvents (dimethyl sulfoxide, sulfolane, etc.), halogenated hydrocarbons (Chloroform, dichloromethane, etc.) and hydrocarbons (hexane, toluene, etc.) are mentioned, and water, monoalcohol and monoether are preferred. Two or more of these solvents may be used.
[0012]
The mixed solution preferably contains 0.01 to 10 mol / l, more preferably 0.05 to 5 mol / l of monomer (a-1), and preferably 0.0001 to 10 mol / l of oxidizing agent (a-2). More preferably, it contains 0.001-5 mol / l. That is, the mixed solution contains the monomer (a-1) based on the mixed solution, preferably 0.01 mol / l or more, more preferably 0.05 mol / l or more, preferably 10 mol / l or less, more preferably Contains 5 mol / l or less. The mixed solution preferably contains the oxidizing agent (a-2) based on the mixed solution in an amount of 0.0001 mol / l or more, more preferably 0.001 mol / l or more, preferably 10 mol / l or less, more preferably Contains 5 mol / l or less. The viscosity (temperature 25 ° C.) is preferably 0.1 to 10,000 mPa · s, more preferably 0.1 to 500 mPa · s. That is, the viscosity (temperature 25 ° C.) is preferably 0.1 mPa · s or more, preferably 10,000 mPa · s or less, and more preferably 500 mPa · s or less. The polymerization conditions may be known polymerization conditions, and the polymerization is preferably carried out in the temperature range of −100 ° C. to 200 ° C. for 1 minute to 48 hours, particularly preferably in the range of 0 ° C. to 150 ° C. for 1 to 60 minutes. The polymerization is preferably performed on the capacitor element in the above combination, and the polymerization may be repeated a plurality of times.
[0013]
(II) Method by Gas Phase Chemical Polymerization In the case of the polymerization, the oxidative polymerization performed in (I) is performed in the gas phase, and preferably in the gas phase containing (a-1) in advance (a -2) is polymerized after placing the capacitor element immersed in the solution.
[0014]
(A-1), (a-2), the solvent, etc. can use the same thing as what was mentioned by (I), and a preferable thing is also the same as (I). The oxidant solution preferably contains (a-2) in an amount of 0.0001 to 10 mol / l, more preferably 0.001 to 5 mol / l. That is, the oxidant solution preferably contains (a-2) at 0.0001 mol / l or more, more preferably 0.001 mol / l or more, preferably 10 mol / l or less, more preferably 5 mol / l or less. The polymerization conditions may be known polymerization conditions, and the polymerization is preferably carried out in the temperature range of -60 ° C to 200 ° C for 1 minute to 48 hours, more preferably in the range of -15 ° C to 25 ° C for 1 to 60 minutes. The polymerization is preferably performed on the capacitor element in the above combination, and the polymerization may be repeated a plurality of times.
[0015]
(III) Method by Electrolytic Polymerization In the case of the polymerization, the capacitor element is immersed in a solution containing (a-1) and preferably (a-2), and polymerization is conducted by energization. The polymerization of (I) and (II) is chemical oxidative polymerization, while (III) is electrolytic polymerization.
[0016]
(A-1), (a-2) and the same solvent as the above (I) and (II) can be used, and (a-1) is preferably the same as (I). (A-2) is preferably a protonic acid and a salt thereof, a peracid and a salt thereof, and particularly preferably a sodium sulfonate having 7 to 30 carbon atoms and an ammonium ammonium sulfonate having 7 to 30 carbon atoms. , Ammonium perchlorate.
[0017]
The solution contains 0.01 to 10 mol / l of monomer (a-1), more preferably 0.05 to 5 mol / l, and preferably 0.00001 to 10 mol / l of oxidizing agent (a-2). Preferably it contains 0.0001-5 mol / l. That is, the solution contains the monomer (a-1) based on the solution, preferably 0.01 mol / l or more, more preferably 0.05 mol / l or more, preferably 10 mol / l or less, more preferably 5 mol / l. 1 or less. In addition, the solution contains the oxidizing agent (a-2) based on the solution, preferably 0.00001 mol / l or more, more preferably 0.0001 mol / l or more, preferably 10 mol / l or less, more preferably 5 mol / l. 1 or less.
[0018]
The polymerization conditions may be known polymerization conditions, preferably energized in a temperature range of −100 ° C. to 200 ° C. for 1 minute to 48 hours, more preferably in the range of 10 ° C. to 100 ° C. for 1 minute to 60 minutes. Do.
[0019]
Polymerization is preferably carried out by electrolysis on the capacitor element by the constant potential method or constant current method in the above combination, and a polymer layer is formed on the capacitor element. In the potentiostatic method, preferably 0.1 to 5 Vvs. In the potential range of SCE (saturated sweet potato electrode), preferably by the constant current method, 0.01-100 mA / cm.²Polymerization is carried out at a current density of The polymerization may be repeated a plurality of times.
[0020]
The polymer (A-1) obtained in (I) to (III) is already on the capacitor element because the polymerization was carried out on the capacitor element. Absent.
[0021]
The polymer formed by these polymerization methods is a conjugated double bond polymer (A-1), and the polymer may be further doped with a dopant (A-2). Doping (or doping) means that the charge transfer occurs between (A-1) and (A-2), and the conductivity of (A-1) is increased. The dopant is an electron-accepting or electron-donating reagent that imparts conductivity to (A-1). When the oxidizing agent (a-2) contains an electron-accepting or electron-donating component, it also acts as a dopant at the time of polymerization. In this case, the polymer formed by the polymerization method is doped simultaneously with the polymerization. Yes. For example, when a transition metal salt is used as the oxidant, the transition metal receives electrons from the polymer to reduce the oxidation number, and the counter ion imparts conductivity to the polymer in an electron donating manner.
[0022]
The following are mentioned as (A-2).
(1) Protic acid; inorganic protic acid (hydrochloric acid, sulfuric acid, nitric acid, fluorosulfuric acid, chlorosulfuric acid, phosphoric acid, hydrofluoric acid, phosphohydrofluoric acid, etc.); low molecular organic acid having a molecular weight of less than 1,000 [phenols (Phenol, naphthol, etc.), C1-C30 aliphatic carboxylic acid (acetic acid, protonic acid, etc.), C7-C30 aromatic carboxylic acid (benzoic acid, phthalic acid, etc.), C1-C30 Aliphatic sulfonic acid (methanesulfonic acid, propanesulfonic acid, etc.), aromatic sulfonic acid having 7 to 30 carbon atoms (benzenesulfonic acid, p-toluenesulfonic acid, etc.)]; weight average molecular weight 1,000-1,000 , 000 high molecular organic acids (polystyrene sulfonic acid, polyvinyl sulfonic acid, etc.), etc .;
[0023]
(2) Halogen and halides: bromine, iodine, bromine iodide, arsenic pentafluoride, antimony pentafluoride, silicon tetrafluoride, phosphorus pentachloride, phosphorus pentafluoride, aluminum chloride, aluminum bromide, iron chloride, Copper chloride etc. Of these, preferred are protonic acids, and more preferred are hydrochloric acid, sulfuric acid, aliphatic carboxylic acids having 1 to 30 carbon atoms, aromatic carboxylic acids having 7 to 30 carbon atoms, and aliphatic sulfones having 1 to 30 carbon atoms. Acid, aromatic sulfonic acid having 7 to 30 carbon atoms, and particularly preferred are aliphatic carboxylic acids having 1 to 30 carbon atoms, aromatic carboxylic acids having 7 to 30 carbon atoms, and aliphatic sulfones having 1 to 30 carbon atoms. Acid, an aromatic sulfonic acid having 7 to 30 carbon atoms. In addition, the dopant (A-2) in this invention may use 1 type, or 2 or more types.
[0024]
The addition of (A-2) may be carried out by a known chemical or electrochemical method after forming (A-1), but preferably, an oxidizing agent is used in combination as described above. In addition, it is preferable to dope simultaneously with the polymerization. In the chemical method, (A-2) is mixed or reacted with (A-1) in the gas phase or in solution to dope, and in the electrochemical method, (A-2) is dissolved in the solution (A-1). And is electrochemically doped by applying a potential using (A-1) as an electrode. Preferably, it is (A) formed on the capacitor element. In this way, the conductive polymer (A) is formed, and the conductivity is preferably 10^-5-10⁵S / cm, more preferably 10^-2-10⁵S / cm. That is, its conductivity is preferably 10^-5S / cm or more, more preferably 10^-2S / cm or more, preferably 10⁵S / cm or less.
[0025]
In the present invention, the organic acid onium salt (B) is formed from an onium cation and an organic acid anion. (B) is an organic acid salt of an onium cation. Specifically, the onium cation is one or more selected from the group of cations consisting of quaternary ammonium, tertiary sulfonium, quaternary phosphonium, and tertiary oxonium. The organic acid anion is one or more organic acid onium salts selected from the group of anions obtained by removing protons from organic acids consisting of carboxylic acids, sulfonic acids, phenols, mono- or dialkyl phosphate esters, and boron complexes. It is preferable.
[0026]
Specific examples of the onium cation used in (B) are described below.
(I) Examples of the quaternary ammonium cation include the following (I-1) to (I-10).
(I-1) Aliphatic quaternary ammonium having an alkyl and / or alkenyl group having 4 to 30 or more carbon atoms; tetramethylammonium, ethyltrimethylammonium, diethyldimethylammonium, triethylmethylammonium, trimethylethylammonium, tetraethyl Ammonium, trimethylpropylammonium, dimethyldipropylammonium, ethylmethyldipropylammonium, butyltrimethylammonium, dimethyldibutylammonium, tetrabutylammonium, tetrahexylammonium, trimethyldecylammonium, etc .;
[0027]
(I-2) Aromatic quaternary ammonium having 6 to 30 or more carbon atoms; trimethylphenylammonium, dimethylethylphenylammonium, triethylphenylammonium and the like;
[0028]
(I-3) alicyclic quaternary ammonium having 3 to 30 or more carbon atoms; N, N-dimethylpyrodinium, N-ethyl-N-methylpyrrolidinium, N, N-diethylpyrrolidinium, N, N-dimethylmorpholinium, N-ethyl-N-methylmorpholinium, N, N-diethylmorpholinium, N, N-dimethylpiperidinium, N, N-diethylpiperidinium, etc .;
[0029]
(I-4) imidazolinium having 3 to 30 or more carbon atoms; 1,2,3-trimethylimidazolinium, 1,2,3,4-tetramethylimidazolinium, 1,3,4-trimethyl 2-ethylimidazolinium, 1,3-dimethyl-2,4-diethylimidazolinium, 1,2-dimethyl-3,4-diethylimidazolinium, 1,2-dimethyl-3-ethylimidazolinium 1,2,3,4-tetraethylimidazolinium, 1,2,3-triethylimidazolinium, 4-cyano-1,2,3-trimethylimidazolinium, 2-cyanomethyl-1,3-dimethylimidazole Linium, 4-acetyl-1,2,3-trimethylimidazolinium, 3-acetylmethyl-1,2-dimethylimidazolinium, 4-methylcarbooxime Ru-1,2,3-trimethylimidazolinium, 3-methoxymethyl-1,2-dimethylimidazolinium, 4-formyl-1,2,3-trimethylimidazolinium, 3-formylmethyl-1,2 -Dimethylimidazolinium, 3-hydroxyethyl-1,2-dimethylimidazolinium, 4-hydroxymethyl-1,2,3-trimethylimidazolinium, etc .;
[0030]
(I-5) imidazolium having 3 to 30 or more carbon atoms; 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1-methyl-3-ethylimidazolium, 1,2,3 -Trimethylimidazolium, 1,3-dimethyl-2-ethylimidazolium, 1,2-dimethyl-3-ethyl-imidazolium, 1,2,3-triethylimidazolium, 1,2,3,4-tetraethylimidazolium Lithium, 1,3-dimethyl-2-phenylimidazolium, 1,3-dimethyl-2-benzylimidazolium, 1-benzyl-2,3-dimethyl-imidazolium, 4-cyano-1,2,3-trimethyl Imidazolium, 3-cyanomethyl-1,2-dimethylimidazolium, 4-acetyl-1,2,3-trimethylimidazolium, 3 Acetylmethyl-1,2-dimethylimidazolium, 4-methylcarbooxymethyl-1,2,3-trimethylimidazolium, 3-methylcarbooxymethyl-1,2-dimethylimidazolium, 4-methoxy-1,2 , 3-trimethylimidazolium, 4-formyl-1,2,3-trimethylimidazolium, 3-formylmethyl-1,2-dimethylimidazolium, 3-hydroxyethyl-1,2-dimethylimidazolium, 2-hydroxy Ethyl-1,3-dimethylimidazolium, N, N′-dimethylbenzimidazolinium, N, N′-diethylbenzimidazolinium, N-methyl-N′-ethylbenzimidazolinium, etc .;
[0031]
(I-6) Tetrahydropyrimidinium having 4 to 30 or more carbon atoms; 1,3-dimethyltetrahydropyrimidinium, 1,2,3-trimethyltetrahydropyrimidinium, 1,2,3,4-tetra Methyltetrahydropyrimidinium, 8-methyl-1,8-diazabicyclo [5,4,0] -7-undecenium, 5-methyl-1,5-diazabicyclo [4,3,0] -5-nonenium, 4- Cyano-1,2,3-trimethyltetrahydropyrimidinium, 3-cyanomethyl-1,2-dimethyltetrahydropyrimidinium, 4-acetyl-1,2,3-trimethyltetrahydropyrimidinium, 3-acetylmethyl-1 , 2-Dimethyltetrahydropyrimidinium, 4-methylcarbooxymethyl-1,2,3-trimethyltetrahydride Pyrimidinium, 4-methoxy-1,2,3-trimethyltetrahydropyrimidinium, 3-methoxymethyl-1,2-dimethyltetrahydropyrimidinium, 4-hydroxymethyl-1,2,3-trimethyltetrahydropyrimidinium, 2-hydroxyethyl-1,3-dimethyltetrahydropyrimidinium and the like;
[0032]
(I-7) C4-C30 or more dihydropyrimidinium; 1,3-dimethyl-2,4- or -2,6-dihydropyrimidinium [these are 1,3-dimethyl-2 , 4 (6) -dihydropyrimidinium, and the same expression is used hereinafter. 1,2,3-trimethyl-2,4 (6) -dihydropyrimidinium, 1,2,3,4-tetramethyl-2,4 (6) -dihydropyrimidinium, 1,2,3 5-tetramethyl-2,4 (6) -dihydropyrimidinium, 8-methyl-1,8-diazabicyclo [5,4,0] -7,9 (10) -undecadienium, 5-methyl- 1,5-diazabicyclo [4,3,0] -5,7 (8) -nonadienium, 2-cyanomethyl-1,3-dimethyl-2,4 (6) -dihydropyrimidinium, 3-acetylmethyl-1 , 2-dimethyl-2,4 (6) -dihydropyrimidinium, 4-methylcarbooxymethyl-1,2,3-trimethyl-2,4 (6) -dihydropyrimidinium, 4-methoxy-1, 2,3-trimethyl-2,4 (6) -dihydride Pyrimidinium, 4-formyl-1,2,3-trimethyl-2,4 (6) -dihydropyrimidinium, 3-hydroxyethyl-1,2-dimethyl-2,4 (6) -dihydropyrimidinium, 2 -Hydroxyethyl-1,3-dimethyl-2,4 (6) -hydropyrimidinium and the like;
[0033]
(I-8) Guanidinium having an imidazolinium skeleton having 3 to 30 or more carbon atoms; 2-dimethylamino-1,3,4-trimethylimidazolinium, 2-diethylamino-1,3,4-trimethylimidazole Linium, 2-diethylamino-1,3-dimethyl-4-ethylimidazolinium, 2-dimethylamino-1-methyl-3,4-diethylimidazolinium, 2-diethylamino-1,3,4-tetraethylimidazo Linium, 2-dimethylamino-1,3-dimethylimidazolinium, 2-diethylamino-1,3-dimethylimidazolinium, 2-diethylamino-1,3-diethylimidazolinium, 1,5,6,7 -Tetrahydro-1,2-dimethyl-2H-imide [1,2a] imidazolinium, 1,5,6,7-te Lahydro-1,2-dimethyl-2H-pyrimido [1,2a] imidazolinium, 1,5-dihydro-1,2-dimethyl-2H-pyrimido [1,2a] imidazolinium, 2-dimethylamino-3 -Cyanomethyl-1-methylimidazolinium, 2-dimethylamino-4-acetyl-1,3-dimethylimidazolinium, 2-dimethylamino-4-methylcarbooxymethyl-1,3-dimethylimidazolinium, 2 -Dimethylamino-3-methylcarbooxymethyl-1-methylimidazolinium, 2-dimethylamino-3-methoxymethyl-1-methylimidazolinium, 2-dimethylamino-4-formyl-1,3-dimethylimidazole Linium, 2-dimethylamino-3-hydroxyethyl-1-methylimidazolinium, 2-dimethyl Amino-4-hydroxy-1,3-dimethyl imidazolinium like;
[0034]
(I-9) Guanidinium having an imidazolium skeleton having 3 to 30 or more carbon atoms; 2-dimethylamino-1,3,4-trimethylimidazolium, 2-diethylamino-1,3,4-trimethylimidazolium, 2-diethylamino-1,3-dimethyl-4-ethylimidazolium, 2-diethylamino-1-methyl-3,4-diethylimidazolium, 2-diethylamino-1,3,4-tetraethylimidazolium, 2-dimethylamino -1,3-dimethylimidazolium, 2-dimethylamino-1-ethyl-3-methylimidazolium, 2-diethylamino-1,3-diethylimidazolium, 1,5,6,7-tetrahydro-1,2- Dimethyl-2H-imide [1,2a] imidazolium, 1,5,6,7-tetrahydro-1 2-dimethyl-2H-pyrimido [1,2a] imidazolium, 1,5-dihydro-1,2-dimethyl-2H-pyrimido [1,2a] imidazolium, 2-dimethylamino-3-cyanomethyl-1-methyl Imidazolium, 2-dimethylamino-4-acetyl-1,3-dimethylimidazolinium, 2-dimethylamino-4-methylcarbooxymethyl-1,3-dimethylimidazolium, 2-dimethylamino-4-methoxy- 1,3-dimethylimidazolium, 2-dimethylamino-3-methoxymethyl-1-methylimidazolium, 2-dimethylamino-3-formylmethyl-1-methylimidazolium, 2-dimethylamino-4-hydroxymethyl- 1,3-dimethylimidazolium, etc .;
[0035]
(I-10) Guanidinium having a tetrahydropyrimidinium skeleton having 4 to 30 or more carbon atoms; 2-dimethylamino-1,3,4-trimethyltetrahydropyrimidinium, 2-diethylamino-1,3,4- Trimethyltetrahydropyrimidinium, 2-diethylamino-1,3-dimethyl-4-ethyltetrahydropyrimidinium, 2-diethylamino-1-methyl-3,4-diethyltetrahydropyrimidinium, 2-dimethylamino-1,3 -Dimethyltetrahydropyrimidinium, 2-diethylamino-1,3-dimethyltetrahydropyrimidinium, 2-diethylamino-1,3-diethyltetrahydropyrimidinium, 1,3,4,6,7,8-hexahydro-1 , 2-Dimethyl-2H-imide [1,2a] pyrimidi 1,3,4,6,7,8-hexahydro-1,2-dimethyl-2H-pyrimido [1,2a] pyrimidinium, 2,3,4,6-tetrahydro-1,2-dimethyl-2H- Pyrimido [1,2a] pyrimidinium, 2-dimethylamino-3-cyanomethyl-1-methyltetrahydropyrimidinium, 2-dimethylamino-4-acetyl-1,3-dimethyltetrahydropyrimidinium, 2-dimethylamino- 4-methylcarbooxymethyl-1,3-dimethyltetrahydropyrimidinium, 2-dimethylamino-3-methylcarbooxymethyl-1-methyltetrahydropyrimidinium, 2-dimethylamino-3-methoxymethyl-1-methyl Tetrahydropyrimidinium, 2-dimethylamino-4-formyl-1,3-dimethylteto Hydro pyrimidinium, 2-dimethylamino-3-hydroxyethyl-1-methyl-tetrahydropyrimidinium chloride, 2-dimethylamino-4-hydroxymethyl-1,3-dimethyl-tetrahydropyrimidinium bromide and the like;
[0036]
(I-11) Guanidinium having a dihydropyrimidinium skeleton having 4 to 30 or more carbon atoms; 2-dimethylamino-1,3,4-trimethyl-2,4 (6) -dihydropyrimidinium, 2- Diethylamino-1,3,4-trimethyl-2,4 (6) -dihydropyrimidinium, 2-dimethylamino-1-methyl-3,4-diethyl-2,4 (6) -dihydropyrimidinium, 2 -Diethylamino-1-methyl-3,4-diethyl-2,4 (6) -dihydropyrimidinium, 2-diethylamino-1,3,4-tetraethyl-2,4 (6) -dihydropyrimidinium, 2 -Diethylamino-1,3-dimethyl-2,4 (6) -dihydropyrimidinium, 2-dimethylamino-1-ethyl-3-methyl-2,4 (6) -dihydropyrimidini 1,6,7,8-tetrahydro-1,2-dimethyl-2H-imide [1,2a] pyrimidinium, 1,6-dihydro-1,2-dimethyl-2H-imide [1,2a] pyrimidinium, 1,6-dihydro-1,2-dimethyl-2H-pyrimido [1,2a] pyrimidinium, 2-dimethylamino-4-cyano-1,3-dimethyl-2,4 (6) -dihydropyrimidinium, 2 -Dimethylamino-4-acetyl-1,3-dimethyl-2,4 (6) -dihydropyrimidinium, 2-dimethylamino-3-acetylmethyl-1-methyl-2,4 (6) -dihydropyrimidi Ni, 2-dimethylamino-3-methylcarbooxymethyl-1-methyl-2,4 (6) -dihydropyrimidinium, 2-dimethylamino-4-methoxy-1,3-dimethyl 2,4 (6) -dihydropyrimidinium, 2-dimethylamino-4-formyl-1,3-dimethyltetrahydropyrimidinium, 2-dimethylamino-3-formylmethyl-1-methyltetrahydropyrimidinium, 2 -Dimethylamino-4-hydroxymethyl-1,3-dimethyl-2,4 (6) -dihydropyrimidinium and the like.
[0037]
(II) Examples of the tertiary sulfonium cation include the following (II-1) to (II-3).
(II-1) Aliphatic tertiary sulfonium having an alkyl and / or alkenyl group having 1 to 30 or more carbon atoms; trimethylsulfonium, triethylsulfonium, ethyldimethylsulfonium, diethylmethylsulfonium and the like;
(II-2) Aromatic tertiary sulfonium having 6 to 30 or more carbon atoms; phenyldimethylsulfonium, phenylethylmethylsulfonium, phenylmethylbenzylsulfonium and the like;
(II-3) An alicyclic tertiary sulfonium having 3 to 30 or more carbon atoms; methylthiolanium, phenylthiolanium, methylthianium, etc .;
[0038]
(III) Examples of the quaternary phosphonium cation include the following (III-1) to (III-3).
(III-1) Aliphatic quaternary phosphonium having an alkyl group and / or alkenyl group having 1 to 30 or more carbon atoms; tetramethylphosphonium, tetraethylphosphonium, tetrapropylphosphonium, tetrabutylphosphonium, methyltriethylphosphonium, methyl Tripropylphosphonium, methyltributylphosphonium, dimethyldiethylphosphonium, trimethylethylphosphonium, trimethylpropylphosphonium, ethyltripropylphosphonium, ethyltributylphosphonium, diethyldibutylphosphonium, triethylbutylphosphonium, propyltributylphosphonium, dipropyldibutylphosphonium, tripropylbutylphosphonium etc;
(III-2) Aromatic quaternary phosphonium having 6 to 30 or more carbon atoms; triphenylmethylphosphonium, diphenyldimethylphosphonium, triphenylbenzylphosphonium and the like;
(III-3) alicyclic quaternary phosphonium having 3 to 30 or more carbon atoms; 1,1-dimethylphosphonium, 1-methyl-1-ethylphosphonium, 1,1-diethylphosphonium, 1,1-dimethylphosphorinanium, 1-methyl-1-ethylphosphorinanium, 1,1-diethylphosphorinanium, 1,1-pentamethylenephosphorinanium, etc .;
[0039]
(IV) Examples of the tertiary oxonium cation include the following (IV-1) to (IV-3).
(IV-1) Aliphatic tertiary oxonium having an alkyl and / or alkenyl group having 1 to 30 or more carbon atoms; trimethyloxonium, triethyloxonium, ethyldimethyloxonium, diethylmethyloxonium and the like;
(IV-2) Aromatic tertiary oxonium having 6 to 30 or more carbon atoms; phenyldimethyloxonium, phenylethylmethyloxonium, phenylmethylbenzyloxonium, etc .;
(IV-3) alicyclic tertiary oxonium having 3 to 30 or more carbon atoms; methyl oxolanium, phenyl oxolanium, methyl oxonium and the like;
[0040]
Of these, preferred are quaternary ammonium cations, and more preferred are aliphatic ammonium having 4 to 30 or more carbon atoms, imidazolinium having 3 to 30 or more carbon atoms, and 3 to 3 carbon atoms. 30 or more imidazoliums, particularly preferred are trimethylethylammonium, dimethyldiethylammonium, triethylmethylammonium, 1,2,3,4-tetramethylimidazolinium, 1,2-dimethyl-3-ethyl Imidazolinium, 1-ethyl-3-methylimidazolium, 1-methyl-3-ethylimidazolium. One or two or more of these onium cations may be used.
[0041]
Specific examples of the organic acid that forms the counter anion of (B) are described below.
Examples of (I) carboxylic acid include the following (I-1) to (I-4).
(I-1) Saturated and unsaturated aliphatic carboxylic acids having 1 to 30 or more carbon atoms;
(I-1-1) Monovalent aliphatic carboxylic acid; formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, verargonic acid, lauric acid, myristic acid, stearic acid Saturated carboxylic acids such as behenic acid, unsaturated carboxylic acids such as acrylic acid, methacrylic acid and oleic acid;
(I-1-2) Divalent or higher aliphatic carboxylic acid; oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, 1,10-decanedicarboxylic acid, 1,12-decane Linear saturated dicarboxylic acid such as dicarboxylic acid, plasylic acid, 1,15-pentadicarboxylic acid, methylmalonic acid, ethylmalonic acid, butylmalonic acid, 3-methyladipic acid, 1,6-decanedicarboxylic acid, diethylmalonic acid 2,2- or 2,3-dimethylsuccinic acid, 2-ethyl-3-methylsuccinic acid, 2,2- or 2,3- or 2,4- or 3,3-dimethylglutaric acid, 3-ethyl- Branched saturated carboxylic acid such as 3-methylglutaric acid, 2-butyloctanedioic acid, 5,6-decanedicarboxylic acid, tricarballylic acid, 1,6,11- or 1,10,11- or 5, , 11-pentadecenyl country carboxylic acid, 1,2,3,4-butane tetracarboxylic acid, maleic acid, fumaric acid, and unsaturated dicarboxylic acids such as citraconic acid;
(I-1-3) oxyaliphatic carboxylic acid; glycolic acid, lactic acid, tartaric acid and the like;
(I-1-4) thioaliphatic carboxylic acid; thiodipropionic acid and the like;
[0042]
(I-2) an aromatic carboxylic acid having 7 to 30 or more carbon atoms;
(I-2-1) monovalent aromatic carboxylic acid; benzoic acid, cinnamic acid, naphthoic acid and the like;
(I-2-2) Divalent or higher valent aromatic carboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, etc .;
(I-2-3) oxyaromatic carboxylic acid; salicylic acid, mandelic acid and the like;
[0043]
(I-3) C3-C30 or more alicyclic carboxylic acid; cyclobutene-1,2-dicarboxylic acid, cyclopentene-1,2-dicarboxylic acid, 1,2- or 1,4-cyclohexanedicarboxylic acid 2- or 3-methyl-1,4-cyclohexanedicarboxylic acid, furan-2,3-dicarboxylic acid, bicyclo [2,2,1] hept-2-ene-2,3-dicarboxylic acid, bicyclo [2, 2,1] hepta-2,5-diene-2,3-dicarboxylic acid and the like;
[0044]
(I-4) Polymers and copolymers of monomers having a carboxyl group; as polymerizable monomers having a carboxyl group, carboxyl groups such as (meth) acrylic acid, cinnamic acid, vinylbenzoic acid, and polymerizable double bonds And a carboxylic acid having 3 to 30 carbon atoms. The polymerization conditions and the like may be a known method, and the degree of polymerization is preferably 16 to 10,000, more preferably 20 to 1,000. Of these, preferred as the carboxylic acid are adipic acid, 1,6-decanedicarboxylic acid, phthalic acid, and benzoic acid.
[0045]
Examples of (II) sulfonic acid include the following (II-1) to (II-3).
(II-1) Saturated and unsaturated aliphatic sulfonic acids having 1 to 30 or more carbon atoms;
(II-1-1) monovalent aliphatic sulfonic acid; methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, isopropylsulfonic acid, butanesulfonic acid, isobutylsulfonic acid, t-butylsulfonic acid, pentanesulfonic acid, iso Saturated carboxylic acids such as pentylsulfonic acid, hexanesulfonic acid, nonanesulfonic acid, decanesulfonic acid, undecanesulfonic acid, dodecanesulfonic acid, tridecanesulfonic acid, tetradecanesulfonic acid, n-octylsulfonic acid, dodecylsulfonic acid, cetylsulfonic acid, etc. Acids, ethylene sulfonic acids, 1-propene-1-sulfonic acids, benzyl sulfonic acids, unsaturated sulfonic acids such as phenylethane sulfonic acids, etc .;
(II-1-2) Divalent or higher aliphatic sulfonic acid; methionic acid, 1,1-ethanedisulfonic acid, 1,2-ethanedisulfonic acid, 1,1-propanedisulfonic acid, 1,3-propanedisulfonic acid , Polyvinyl sulfonic acid, etc .;
(II-1-3) oxyaliphatic sulfonic acid; isethionic acid, 3-oxy-propanesulfonic acid and the like;
(II-1-4) sulfoaliphatic carboxylic acid; sulfoacetic acid, sulfosuccinic acid and the like;
[0046]
(II-2) an aromatic sulfonic acid having 6 to 30 or more carbon atoms;
(II-2-1) Monovalent monocyclic aromatic sulfonic acid; benzenesulfonic acid, p-toluenesulfonic acid, o-toluenesulfonic acid, m-toluenesulfonic acid, o-xylene-4-sulfonic acid, m -Xylene-4-sulfonic acid, 4-dodecylbenzenesulfonic acid, 4-octylbenzenesulfonic acid, 2-methyl-5-isopropylbenzenesulfonic acid and the like;
(II-2-2) monovalent polycyclic aromatic sulfonic acid; alkylnaphthalenesulfonic acid such as naphthalenesulfonic acid and triisopropylnaphthalenesulfonic acid, anthracenesulfonic acid, phenanthrenesulfonic acid and the like;
(II-2-3) Divalent or higher aromatic sulfonic acid; m-benzenedisulfonic acid, 1,4-naphthalenesulfonic acid, 1,5-naphthalenedisulfonic acid, 1,6-naphthalenedisulfonic acid, 2,6- Naphetalenedisulfonic acid, 2,7-naphthalenedisulfonic acid, sulfonated polystyrene, etc .;
(II-2-4) oxyaromatic sulfonic acid; phenol-2-sulfonic acid, phenol-3-sulfonic acid, phenol-4-sulfonic acid, anisole-o-sulfonic acid, anisole-m-sulfonic acid, phenetol- o-sulfonic acid, phenetole-m-sulfonic acid, phenol-2,4-disulfonic acid, phenol-2,4,6-trisulfonic acid, anisole-2,4-disulfonic acid, phenetol-2,5-disulfonic acid 2-oxytoluene-4-sulfonic acid, pyrocatechin-4-sulfonic acid, veratol-4-sulfonic acid, resorcin-4-sulfonic acid, 2-oxy-1-methoxybenzene-4-sulfonic acid, 1,2 -Dioxybenzene-3,5-disulfonic acid, resorcin-4,6-disulfonic acid, hydroquinonesulfonic acid, hydride Quinone-2,5-disulfonic acid, 1,2,3-oxybenzene-4-sulfonic acid, and the like;
(II-2-5) sulfoaromatic carboxylic acid; o-sulfobenzoic acid, m-sulfobenzoic acid, p-sulfobenzoic acid, 2,4-disulfobenzoic acid, 3-sulfophthalic acid, 3,5-disulfophthalic acid 4-sulfoisophthalic acid, 2-sulfoterephthalic acid, 2-methyl-4-sulfobenzoic acid, 2-methyl-3,5-disulfobenzoic acid, 4-propyl-3-sulfobenzoic acid, 2,4,6 -Trimethyl-3-sulfobenzoic acid, 2-methyl-5-sulfoterephthalic acid, 5-sulfosalicylic acid, 3-oxy-4-sulfobenzoic acid and the like;
(II-2-6) thioaromatic sulfonic acid; thiophenol sulfonic acid, thioanisole-4-sulfonic acid, thiophenetol-4-sulfonic acid, etc .;
(II-2-7) Other aromatic sulfonic acids having functional groups; benzaldehyde-o-sulfonic acid, benzaldehyde-2,4-disulfonic acid, acetophenone-o-sulfonic acid, acetophenone-2,4-disulfonic acid, benzophenone -O-sulfonic acid, benzophenone-3,3'-disulfonic acid, 4-aminophenol-3-sulfonic acid, anthraquinone-1-sulfonic acid, anthraquinone-1,5-disulfonic acid, anthraquinone-1,8-disulfonic acid Anthraquinone-2,6-disulfonic acid, 2-methylanthraquinone-1-sulfonic acid, etc .;
[0047]
(II-3) Aliphatic carboxylic acid having 3 to 30 or more carbon atoms; cyclopentanesulfonic acid, cyclohexanesulfonic acid and the like; among these, preferred as sulfonic acids are p-toluenesulfonic acid and triisopropylnaphthalene Sulfonic acid, naphthalene sulfonic acid, and phenol-4-sulfonic acid.
[0048]
(III) The following (III-1) is mentioned as phenols.
(III-1) substituted or unsubstituted phenol having 6 to 30 or more carbon atoms;
(III-1-1) monovalent phenol; phenol, naphthol, cyclohexylphenol, cresol, xylenol, ethylphenol, n and isopropylphenol, n and isoamylphenol, isononylphenol, isododecylphenol, eugenol, guaiacol and the like;
(III-1-2) divalent or higher phenols; catechol, resorcin, pyrogallol, phloroglucin and the like;
[0049]
(IV) Examples of the mono- or dialkyl phosphate ester include the following (IV-1) to (IV-2).
(IV-1) C1-C30 or more monoalkyl phosphate ester; methyl phosphate ester, isopropyl phosphate ester, butyl phosphate ester, 2-ethylhexyl phosphate ester, isodecyl phosphate ester, etc .;
(IV-2) a dialkyl phosphate having 2 to 30 or more carbon atoms; dimethyl phosphate, diisopropyl phosphate, dibutyl phosphate, di (2-ethylhexyl) phosphate, diisodecyl phosphate, etc .;
[0050]
(V) Examples of the boron complex include the following (V-1) to (V-2).
(V-1) Alcoholic hydroxyl group-containing compound complex of boric acid; boric acid ethylene glycol complex, boric acid trimethylene glycol complex and the like;
(V-2) Phosphoric acid and / or phosphoric acid ester complex of boric acid; boric acid methyl phosphate complex, boric acid ethyl phosphate complex and the like; As the details of the boron complex, those described in Japanese Patent No. 2966451 can be used.
[0051]
Among these, carboxylic acid and sulfonic acid are preferable, carboxylic acid and aromatic sulfonic acid are more preferable, and carboxylic acid and polycyclic aromatic sulfonic acid are particularly preferable. One or two or more of these organic acid anions may be used.
[0052]
The production method of (B) is not particularly limited. For example, in the case of a quaternary ammonium organic acid salt, a tertiary amine is quaternized with an alkylating agent (alkyl halide, alkylsulfuric acid, etc.) and further halogenated. It is obtained by changing ions to hydroxide ions and then reacting them with an organic acid. The details of this production method are described in International Publication No. WO95 / 15572, Japanese Patent No. 2964244, etc., and can be produced by the same production method.
[0053]
A tertiary sulfonium salt is obtained by tertiaryizing a sulfide with an alkylating agent (alkyl halide, alkylsulfuric acid, etc.), further changing a halogen ion to a hydroxide ion and then reacting with an organic acid. Details of this production method are described in detail in J.H. P. Marino, “Topics in Sulfur Chemistry”, vol. 1, 1976, p. It can be manufactured by the same manufacturing method.
[0054]
The quaternary phosphonium salt is obtained by quaternizing a tertiary phosphine with an alkylating agent (alkyl halide, alkylsulfuric acid, etc.), further changing a halogen ion to a hydroxide ion and then reacting with an organic acid. can get. For details of this production method, see P.I. Beck “Organic Phosphorus Compound”, vol. 2, 1972, Chapter. 4, p. 189, etc., and the same method can be applied.
[0055]
A tertiary oxonium salt is obtained by tertiaryizing an ether with an alkylating agent (alkyl halide, alkylsulfuric acid, etc.), further changing a halogen ion to a hydroxide ion and then reacting with an organic acid. Details of this production method are described in G.H. W. Wheland, “Advanced Organic Chemistry” 1949, p. 38, etc., and the same method can be applied.
[0056]
In the thus obtained (B), the equivalent ratio of the onium cation to the organic acid anion is preferably onium cation: organic acid anion = 1: 0.2-3 from the viewpoint of withstand voltage and heat resistance, Preferably it is 1: 0.5-1.5. When the organic acid anion is 0.2 or more, the withstand voltage is high, and when it is 3 or less, the heat resistance is excellent.
[0057]
The electrolyte used for the electrolytic capacitor in the present invention comprises (A) and (B). The weight ratio of (A) to (B) is preferably (A) :( B) = 1: 0.1-5 from the viewpoint of conductivity and withstand voltage, more preferably (A) :( B ) = 1: 0.2-2. When (B) is 0.1 or more, the withstand voltage is high, and when it is 5 or less, the conductivity is excellent. That is, the weight (B) / weight (A) is preferably 0.1 or more, more preferably 0.2 or more from the viewpoint of withstand voltage, and preferably 5 or less, more preferably from the viewpoint of conductivity. Is 2 or less.
[0058]
In the present invention, the organic acid onium salt (B) may be introduced into a capacitor element by forming the conductive polymer (A) and then impregnating like an electrolytic capacitor using a conventional electrolytic solution. Further, the (B) may be added to the capacitor element simultaneously with the polymerization by forming the (A).
[0059]
The electrolyte of the present invention further improves spark voltage, chemical conversion improvement, leakage current reduction, hydrogen gas absorption, capacitance change prevention, short circuit prevention, corrosion prevention, washing resistance improvement, flame resistance, impregnation improvement, etc. And various additives can be added as they are or in the form of salts. Examples of additives include phosphorus compounds (phosphoric acid, phosphorous acid, hypophosphorous acid, phosphoric acid esters, phosphonic acids, etc.), boron compounds (boric acid, boron oxide, boric acid esters, boron and hydroxyl groups, and / or Or a complex with a compound having a carboxyl group), a nitro compound (nitrobenzoic acid, nitrophenol, nitrophenetole, nitroacetophenone, aromatic nitro compound, etc.), a sulfur compound (sulfonic acid, thiols, complex having a mercapto group) Ring compounds, etc.), benzoic acid derivatives (hydroxybenzoic acid, tetrahydroxybenzoic acid, benzoic acid esters, etc.), phenols (catechol, nitrocatechol, trivalent phenols, etc.), oxyacids (glycolic acid, tartaric acid, citric acid, etc.) , Polyoxyethylene and / or polyoxypropylene derivatives (polyol Siethylene nonylphenyl ether, polyoxyethylene castor oil, etc.), compounds having two or more hydroxyl groups (mannit, hexit, erythlit, sorbit, polyglycerin, saccharides, celluloses, starches, etc.), polymer compounds (Polyvinyl alcohols, polyalkylene glycol, polyalkylene glycolic acid, polyacrylamide, modified silicone oil, etc.), tungstic acid, heteropolyacid (silicotungstic acid, phosphotungstic acid, phosphomolybdic acid, etc.), particulate inorganic compound (silicic anhydride) , Titanium oxide, hydrotalcites, etc.), amino acids and the like. The amount of the additive is preferably 10% by weight or less, more preferably 5% by weight or less of the electrolyte from the viewpoint of conductivity.
[0060]
The electrolyte of the present invention may contain a solvent as long as it does not cause characteristic deterioration, but is preferably solid. Examples of the solvent include monoalcohol (methanol, ethanol, propanol, isopropanol, etc.), glycol (ethylene glycol, diethylene glycol, triethylene glycol, tripropylene glycol, etc.), monoether (methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol). Tall, butyl carbitol, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, tetrahydrofuran, etc.), diethers (ethylene glycol dimethyl ether, ethylene glycol diethyl ether, Diethylene glycol ethyl methyl ether Diglyme, triglyme, tetraethylene glycol dimethyl ether, 1,3-dioxane, etc., nitrile (acetonitrile, benzonitrile, etc.), ketone (acetone, methyl ethyl ketone, etc.), amide (dimethylformamide, dimethylacetamide, etc.), carbonate (ethylene carbonate, propylene) Carbonates, etc.), esters (ethyl acetate, diethyl maleate, etc.), lactones (γ-butyrolactone, δ-valerolactone, etc.), sulfur-containing solvents (dimethyl sulfoxide, sulfolane, etc.), halogenated hydrocarbons (chloroform, dichloromethane, etc.), Examples include hydrocarbons (hexane, toluene, etc.), preferably glycol and lactone. Two or more of these solvents may be used. The amount of the solvent is preferably 10% by weight or less of the electrolyte, more preferably 5% by weight or less, and particularly preferably 1% by weight or less. In the electrolyte, the moisture is preferably 1% or less, more preferably 0.3% or less, and the content of corrosive ions such as alkali metal ions and halogen ions is preferably 10 ppm or less, more preferably 1 ppm. It is as follows. When the water content is 1% or less, the electrolyte performance does not deteriorate, and when the corrosive ion content is 10 ppm or less, the electrode does not corrode.
[0061]
The electrolyte in the present invention is used for an electrolytic capacitor element. The electrolytic capacitor element is not particularly limited. For example, an anode foil made of a valve metal having a dielectric oxide film formed on the surface thereof in a wound aluminum electrolytic capacitor, and a cathode foil with a separator interposed therebetween. It may be a capacitor element configured by rotating, an electrolyte made of a conductive polymer (A) and an organic acid onium salt (B) is provided between the anode foil and the cathode foil, and the capacitor element is, for example, After being housed in the bottomed cylindrical aluminum case, the aluminum electrolytic capacitor can be configured by sealing the opening of the aluminum case with a sealing agent. According to this electrolytic capacitor, by utilizing the high conductivity of the conductive polymer (A), the resistance between the electrodes can be remarkably reduced in the conductive portion, and as a result, an electrolytic capacitor having excellent impedance characteristics can be obtained. It is possible to obtain an electrolytic capacitor with a high leakage voltage and a low leakage current by interposing an organic acid onium salt (B) having a capability of repairing a dielectric oxide film of a valve action metal at the same time. Has the effect of being able to.
[0062]
【Example】
Next, specific examples of the present invention will be described, but the present invention is not limited thereto.
[0063]
Reference example 1
A capacitor element was obtained by winding with a separator interposed between the anode aluminum foil and the cathode aluminum foil. The capacitor element was immersed in 5 ml of a water-ethanol (1: 2) solution containing 0.5 g of ethylenedioxythiophene and 2.0 g of iron p-toluenesulfonate at room temperature for 10 minutes, pulled up, and then dried at 105 ° C. for 10 minutes. The polymerization process was repeated 10 times to form a conductive polymer layer composed of chemically polymerized polyethylene dioxythiophene between the electrode foil and the electrode foil, and then the capacitor element was washed with water and dried (at 105 ° C. for 10 minutes). Thereafter, 1 g of phthalic acid 1,2,3,4-tetramethylimidazolinium salt (phthalic acid / 1,2,3,4-tetramethylimidazolinium functional group equivalent ratio = 1 / 1) was impregnated to obtain an aluminum electrolytic capacitor element having a rated voltage of 50 V and a capacitance of 220 μF. After sealing this capacitor element together with a sealing member in an aluminum metal case, the opening was sealed by a curling process to constitute an aluminum electrolytic capacitor (size: φ10 mm × L10.2 mm).
[0064]
Examples 2, 4, 5, 7, and 8 and Reference Examples 3 and 6 are referred to as Reference Example 1.Except that the conductive polymer or organic acid onium salt described in Table 1 was used instead of the conductive polymer or organic acid onium salt.Reference example 1As well as.
[0065]
Comparative Example 1 A capacitor element was obtained by winding a separator between an anode aluminum foil and a cathode aluminum foil. Thereafter, the capacitor element was impregnated with the electrolytic solution 1 to obtain an aluminum electrolytic capacitor element having a rated voltage of 50 V and a capacitance of 220 μF. After enclosing this capacitor element together with a sealing member in an aluminum metal case, the opening was sealed by curling treatment to constitute an aluminum electrolytic capacitor (size: φ13 mm × L10.2 mm).
[0066]
Electrolytic solution 1: 25% γ-butyrolactone solution of 1,2,3,4-tetramethylimidazolinium phthalate.
[0067]
Comparative Example 2Reference example 1Except not impregnated with organic acid onium saltReference example 1And so on.
[0068]
Table 2 shows the present invention.Examples 2, 4, 5, 7, 8 and Reference Examples 3, 6And the initial characteristics [capacitance at 120 Hz, impedance at 100 kHz, leakage current value, and number of occurrence of short circuit (defect) during aging treatment] for the aluminum electrolytic capacitors of Comparative Examples 1 and 2. In all cases, the number of tests was 50, and the initial characteristics were shown by the average value (excluding the short product).
[0069]
As is clear from Table 2, in the aluminum electrolytic capacitor configured using only the electrolytic solution of Comparative Example 1,Examples 2, 4, 5, 7, 8 and Reference Examples 3, 6The impedance is significantly larger than In Comparative Example 2, although the impedance characteristic is good, the repair capability of the oxide film is remarkably small, and therefore the occurrence rate of short circuit during aging is high.
[0070]
【The invention's effect】
The electrolytic capacitor using the electrolyte comprising the conductive polymer (A) and the organic acid onium salt (B) according to the present invention has the following effects.
(1) Low leakage current and high withstand voltage (2) Excellent impedance characteristics (3) Excellent reliability (4) Easy manufacturing process.
[Table 1]
[Table 2]

Claims (10)

Conductive polymer (A) and onium which are compounds obtained by doping a conjugated double bond polymer (A-1) with an aliphatic sulfonic acid having 1 to 30 carbon atoms and an aromatic sulfonic acid having 7 to 30 carbon atoms It consists of an organic acid onium salt (B) in which the cation is imidazolinium having 3 to 30 or more carbon atoms, imidazolium having 3 to 30 or more carbon atoms, and the organic acid anion is a sulfonate anion, and contains a solvent A solid electrolytic capacitor characterized by using an electrolyte that does not . The onium chaotin is one or more selected from imidazolinium, 1-ethyl-3-methylimidazolium, and 1-methyl-3-ethylimidazolium having 3 to 30 or more carbon atoms. The solid electrolytic capacitor described. The solid electrolytic capacitor according to claim 1 , wherein (A-1) is one or more selected from the group consisting of polypyrrole, polythiophene, polyethylenedioxythiophene, and polyaniline. The onium cation of (B) is 1,2,3,4-tetramethylimidazolinium, 1,2-dimethyl-3-ethylimidazolinium, 1-ethyl-3-methylimidazolium, 1-methyl- The solid electrolytic capacitor according to any one of claims 1 to 3 , which is one or more selected from 3-ethylimidazolium. The solid electrolytic capacitor according to any one of claims 1 to 4 , wherein the organic acid anion (B) is an anion obtained by removing a proton from an aromatic sulfonic acid. (B) the solid electrolytic capacitor according to any one of claims 1 to 5 organic acid anion is an anion obtained by removing a proton from polycyclic aromatic sulfonic acid. Wherein (A) and the weight ratio of (B) is (A) :( B) = 1: The solid electrolytic capacitor according to any one of claims 1 to 6 which is 0.1-5. The solid electrolytic capacitor according to any one of claims 1 to 7 , wherein an equivalent ratio of the onium cation to the organic acid anion in (B) is onium cation: organic acid anion = 1: 0.2-3. It is a composition for solid electrolytic capacitors of any one of Claims 1-8 , Comprising: The composition for electrolyte formation which consists of the constituent monomer of said (A), and said (B). The organic acid onium salt for solid electrolytic capacitors according to any one of claims 1 to 9 .