Electrolytic capacitor

Abstract

An electrolytic capacitor according to the present disclosure comprises a capacitor element and a liquid component. The capacitor element comprises: an anode foil having a dielectric layer; a cathode foil disposed facing the dielectric layer; a separator interposed between the anode foil and the cathode foil; and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator. The conductive polymer layer contains a conductive polymer. A solid-liquid electrolyte that includes the conductive polymer layer and the liquid component contains a first cationic component, a second cationic component, and an anionic component. The conductive polymer layer contains the first cationic component. The liquid component contains the second cationic component and the anionic component. In the solid-liquid electrolyte, the ratio A of the number of moles of the first cationic component, the ratio B of the number of moles of the anionic component, and the ratio C of the number of moles of the second cationic component to the mass of the conductive polymer satisfy a predetermined relationship.

Description

electrolytic capacitor

[0001] The present invention relates to an electrolytic capacitor.

[0002] An electrolytic capacitor, for example, includes a capacitor element and an electrolyte. The capacitor element typically includes an anode foil having a dielectric layer, a cathode foil facing the dielectric layer, and a separator interposed between the anode foil and the cathode foil. Known examples of such electrolytic capacitors include an electrolyte containing a liquid component (e.g., an electrolytic solution) that fills the voids in the capacitor element and a conductive polymer interposed between the anode foil and the cathode foil. In other words, electrolytic capacitors with a solid-liquid electrolyte are known.

[0003] Patent Document 1 below describes an electrolytic capacitor that includes a capacitor element formed of an anode foil and a cathode foil facing each other, and an electrolyte layer formed within the capacitor element, the electrolyte layer having a solid electrolyte layer containing a dopant and a conjugated polymer, and a liquid filled in voids within the capacitor element on which the solid electrolyte layer is formed, the electrolyte layer having a molar ratio of cationic components to 1 mol of functional groups that can contribute to a doping reaction of the dopant of 0.2 to 6. Patent Document 1 below also describes that an electrolytic capacitor configured as described above is less likely to experience a sudden increase in ESR (equivalent series resistance) even after being exposed to thermal stress such as in a reflow soldering process (hereinafter also referred to as a reflow process) when mounted on a substrate or the like.

[0004] Patent No. 7196919

[0005] In recent years, there has been an increasing demand for electrolytic capacitors after the reflow process to not only suppress an increase in equivalent series resistance, but also to suppress a decrease in capacitance and an increase in leakage current.

[0006] However, in any of the known documents, including Patent Document 1, sufficient consideration has not yet been given to simultaneously achieving the three goals of suppressing the decrease in capacitance, the increase in leakage current, and the increase in equivalent series resistance for electrolytic capacitors after the reflow process.

[0007] Therefore, the present disclosure provides an electrolytic capacitor that can simultaneously suppress a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance even after a reflow process.

[0008] One aspect of the present invention is an electrolytic capacitor including a capacitor element and a liquid component, the capacitor element including an anode foil having a dielectric layer, a cathode foil disposed so as to face the dielectric layer, a separator interposed between the anode foil and the cathode foil, and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, the conductive polymer layer including a conductive polymer, a solid-liquid electrolyte including the conductive polymer layer and the liquid component including a first cation component, a second cation component, and an anion component, the conductive polymer layer including the first cation component, a second cation component, and an anion component, the liquid component includes the second cationic component and the anionic component; and in the solid-liquid electrolyte, when the ratio of the number of moles of the first cationic component to the mass of the conductive polymer is A (mol / kg), the ratio of the number of moles of the anionic component to the mass of the conductive polymer is B (mol / kg), and the ratio of the number of moles of the second cationic component to the mass of the conductive polymer is C (mol / kg), the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B≦1.01.

[0009] Another aspect of the present invention relates to an electrolytic capacitor including a capacitor element and a liquid component, the capacitor element including an anode foil having a dielectric layer, a cathode foil arranged so as to face the dielectric layer, a separator interposed between the anode foil and the cathode foil, and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, the conductive polymer layer including a conductive polymer, a solid-liquid electrolyte including the conductive polymer layer and the liquid component including a first cation component and an anion component, the conductive polymer layer including the first cation component, and the liquid component including the anion component, wherein, in the solid-liquid electrolyte, a ratio A (mol / kg) of the number of moles of the first cation component to the mass of the conductive polymer is defined as A, and a ratio B (mol / kg) of the number of moles of the anion component to the mass of the conductive polymer is defined as B, and the ratio A and the ratio B satisfy the relationship 0.20≦A / B≦1.01.

[0010] According to the present disclosure, it is possible to provide an electrolytic capacitor that can simultaneously suppress a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance even after a reflow process.

[0011] 1 is a schematic cross-sectional view of an electrolytic capacitor according to an embodiment of the present disclosure; FIG. 2 is a schematic exploded view of a portion of a capacitor element included in the electrolytic capacitor of FIG.

[0012] Below, embodiments of the present disclosure will be described using examples, but the present disclosure is not limited to the examples described below. In the following description, specific numerical values ​​and materials may be exemplified, but other numerical values, materials, etc. may be applied as long as the effects of the present disclosure are obtained. Note that known components may be applied to components characteristic of the present disclosure. In this specification, when a "range from numerical value A to numerical value B" is mentioned, the range includes numerical value A and numerical value B.

[0013] In the following description, when lower and upper limits of numerical values ​​relating to specific physical properties, conditions, etc. are exemplified, any of the exemplified lower limits and any of the exemplified upper limits can be arbitrarily combined, as long as the lower limit is not equal to or greater than the upper limit. When multiple materials are exemplified, one of them can be selected and used alone, or two or more can be used in combination, unless otherwise specified.

[0014] The present disclosure encompasses any combination of two or more features arbitrarily selected from the appended claims, i.e., any combination of two or more features arbitrarily selected from the appended claims can be combined unless a technical contradiction arises.

[0015] [First Embodiment] The electrolytic capacitor according to the first embodiment of the present disclosure includes a capacitor element and a liquid component. In the electrolytic capacitor according to the first embodiment of the present disclosure, the capacitor element includes an anode foil having a dielectric layer, a cathode foil disposed opposite the dielectric layer, a separator interposed between the anode foil and the cathode foil, and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator. In the electrolytic capacitor according to the first embodiment of the present disclosure, the conductive polymer layer includes a conductive polymer, and the solid-liquid electrolyte including the conductive polymer layer and the liquid component includes a first cationic component, a second cationic component, and an anionic component. In the electrolytic capacitor according to the first embodiment of the present disclosure, the conductive polymer layer includes a first cationic component, and the liquid component includes a second cationic component and an anionic component. In the electrolytic capacitor according to the first embodiment of the present disclosure, in the solid-liquid electrolyte, when the ratio of the number of moles of the first cation component to the mass of the conductive polymer is A (mol / kg), the ratio of the number of moles of the anion component to the mass of the conductive polymer is B (mol / kg), and the ratio of the number of moles of the second cation component to the mass of the conductive polymer is C (mol / kg), the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B≦1.01.

[0016] In the electrolytic capacitor according to the first embodiment of the present disclosure, it is important that, when the conductive polymer layer containing a conductive polymer contains a first cationic component, the liquid component contains a second cationic component and an anionic component, and the ratio of the number of moles of the first cationic component to the mass of the conductive polymer is A (mol / kg), the ratio of the number of moles of the anionic component to the mass of the conductive polymer is B (mol / kg), and the ratio of the number of moles of the second cationic component to the mass of the conductive polymer is C (mol / kg), it is important that the ratios A, B, and C satisfy the relationship 0.20≦(A+C) / B≦1.01. The reason for this is explained below.

[0017] In electrolytic capacitors, the conductive polymer layer is often formed by immersing an anode foil having a dielectric layer on at least one of its major surfaces in a polymer dispersion containing a conductive polymer. To increase capacitance, such anode foils often have at least one surface roughened by etching or other methods. In such cases, it is preferable to thoroughly impregnate the pores with the polymer dispersion to fully extract capacitance from the interior of the pores formed by the roughening. To fully impregnate the pores with the polymer dispersion, it is desirable for the polymer dispersion to have high wettability with at least one of the major surfaces of the anode foil. To enhance this wettability, it is desirable to incorporate a cationic component into the polymer dispersion. While conductive polymers are often doped with dopants, the presence of an excess of cationic components can reduce the dopant's performance.

[0018] Furthermore, in a solid-liquid electrolyte containing a conductive polymer layer and a liquid component, if the amount of at least one of the first cationic component contained in the conductive polymer layer and the second cationic component contained in the liquid component is excessively small relative to the anionic component, the anionic component and the cationic component are not sufficiently dissociated in the solid-liquid electrolyte, resulting in poor electrical conductivity. In such a case, when exposed to thermal stress such as a reflow process, the formation of an oxide film by the anionic component on at least one main surface of the anode foil is difficult to proceed sufficiently. In other words, the self-repair function of the oxide film is not fully exerted on at least one surface of the anode foil. Furthermore, when the self-repair function of the oxide film is not fully exerted, leakage current increases. Furthermore, poor electrical conductivity of the solid-liquid electrolyte results in a decrease in the equivalent series resistance of the electrolytic capacitor.

[0019] Furthermore, after the electrolytic capacitor is subjected to thermal stress, dedoping may occur in the conductive polymer, causing structural defects in the conductive polymer, which may result in a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance.

[0020] However, in the electrolytic capacitor according to the first embodiment of the present disclosure, when the ratio of the number of moles of the first cationic component to the mass of the conductive polymer is A (mol / kg), the ratio of the number of moles of the anionic component to the mass of the conductive polymer is B (mol / kg), and the ratio of the number of moles of the second cationic component to the mass of the conductive polymer is C (mol / kg), the ratios A, B, and C satisfy the relationship 0.20≦(A+C) / B≦1.01, i.e., the ratios of the first cationic component and the second cationic component to the anionic component are appropriately balanced. Therefore, even when the electrolytic capacitor is subjected to thermal stress such as a reflow process, it is believed that a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance can be sufficiently suppressed.

[0021] In the electrolytic capacitor according to the first embodiment, the ratios A, B, and C preferably satisfy the relationship 0.20≦(A+C) / B<1. That is, in the solid-liquid electrolyte, the sum of the number of moles of the first cationic component and the second cationic component is preferably smaller than the number of moles of the anionic component. By satisfying this relationship, undoping in the conductive polymer can be further suppressed. This further suppresses defects in the structure of the conductive polymer.

[0022] The mass of the conductive polymer can be determined, for example, according to the following procedure 1. Procedure 1: (1) An anode foil, a separator, and a cathode foil are stacked in this order and wound up to obtain a first winding, and the mass (initial mass) W0 of the first winding is measured. (2) A first cation component-containing polymer dispersion containing a first cation component and a conductive polymer is impregnated into the first winding to obtain a second winding, and the second winding is then dried to obtain a third winding. Then, the mass W1 of the third winding is measured. (3) The value of W1 - W0 is calculated, and the mass of the conductive polymer is calculated using this calculated value and the initial concentrations of the first cation component and the conductive polymer in the first cation component-containing polymer dispersion.

[0023] The mass of the conductive polymer can also be determined, for example, by the following procedure 2. Procedure 2: (1) Disassemble the capacitor element and remove the anode foil, separator, and cathode foil. (2) Immerse the anode foil, separator, and cathode foil in water or an organic solvent and irradiate them with ultrasound or the like to remove the conductive polymer (including the first cation component). (3) After measuring the mass of the removed conductive polymer, obtain spectra for the conductive polymer and the first cation component by Raman spectroscopy or time-of-flight secondary ion mass spectrometry (TOFSIMS), and analyze these spectra to determine the mass of the conductive polymer.

[0024] The number of moles of the first cationic component can be measured by NMR (Nuclear Magnetic Resonance) analysis of the main surface of the anode foil of a capacitor element removed from the electrolytic capacitor. The NMR analysis can be performed, for example, under the following conditions. Conditions: Analysis apparatus: ANAANCE500 manufactured by Bruler; Resonance frequency: 500 MHz; Lock solvent: Heavy water; Measurement temperature: Room temperature (23±2°C).

[0025] The number of moles of the second cation component and the anion component can also be measured by NMR analysis of the liquid component collected from the electrolytic capacitor. The NMR analysis of the liquid component can also be carried out under the above conditions.

[0026] <Capacitor Element> As described above, the capacitor element according to the first embodiment of the present disclosure includes an anode foil having a dielectric layer, a cathode foil disposed so as to face the dielectric layer, a separator interposed between the anode foil and the cathode foil, and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator. The anode foil, cathode foil, separator, and conductive polymer layer will be described below.

[0027] (Anode foil) Examples of the anode foil include metal foils containing at least one valve metal such as titanium, tantalum, aluminum, and niobium. The anode foil may be a metal foil of a valve metal (e.g., aluminum foil). The anode foil may contain the valve metal in the form of an alloy containing the valve metal or a compound containing the valve metal. The thickness of the anode foil may be 15 μm or more and 300 μm or less. At least one main surface of the anode foil may be roughened by etching or the like. It is preferable that both main surfaces of the anode foil are roughened.

[0028] A dielectric layer is formed on at least one main surface of the anode foil. The dielectric layer may be formed by chemically treating the anode foil. In this case, the dielectric layer may contain an oxide of a valve metal (e.g., aluminum oxide). The dielectric layer may be formed of any dielectric other than an oxide of a valve metal as long as it functions as a dielectric.

[0029] In the electrolytic capacitor according to the first embodiment of the present disclosure, a conductive polymer layer may or may not be formed on the end surface of the anode foil. However, it is preferable that a conductive polymer layer is also formed on the end surface of the anode foil. For example, in a wound capacitor element such as that shown in FIG. 2, it is preferable that a dielectric layer is formed on the upper and lower end surfaces of the wound body.

[0030] (Cathode foil) The cathode foil is not particularly limited as long as it functions as a cathode. Examples of the cathode foil include metal foils (e.g., aluminum foils). The type of metal contained in the metal foil is not particularly limited. The metal may be a valve metal or an alloy containing a valve metal. The thickness of the cathode foil may be 15 μm or more and 300 μm or less. At least one main surface of the cathode foil may be formed with an etching layer or a dielectric layer, as with the anode foil, if necessary. That is, at least one main surface of the cathode foil may be roughened or chemically treated if necessary.

[0031] The cathode foil may include a conductive coating layer. When the metal foil includes a valve metal, the coating layer may include at least one of carbon and a metal having a lower ionization tendency than the valve metal. This facilitates improving the acid resistance of the metal foil. When the metal foil includes aluminum, the coating layer may include at least one selected from the group consisting of carbon, nickel, titanium, tantalum, and zirconium. In terms of emphasizing low cost and low resistance, the coating layer may include at least one of nickel and titanium.

[0032] The thickness of the coating layer may be 5 nm or more, or 10 nm or more. The thickness of the coating layer may be 200 nm or less. The coating layer may be formed by vapor deposition or sputtering the metal on the metal foil. Alternatively, the coating layer may be formed by vapor deposition of a conductive carbon material on the metal foil or by applying a carbon paste containing a conductive carbon material. Examples of conductive carbon materials include graphite, hard carbon, soft carbon, and carbon black.

[0033] (Separator) A porous sheet can be used for the separator. Examples of porous sheets include woven fabric, nonwoven fabric, and microporous membrane. The thickness of the separator is not particularly limited and may be in the range of 10 μm to 300 μm. Examples of materials for the separator include cellulose, polyethylene terephthalate, polybutylene terephthalate, polyphenyl sulfide, vinylon, nylon, aromatic polyamide, polyimide, polyamideimide, polyetherimide, rayon, and glass.

[0034] (Conductive Polymer Layer) The conductive polymer layer is formed of a conductive polymer. In the electrolytic capacitor according to the first embodiment of the present disclosure, the conductive polymer layer is preferably formed of conductive polymer particles. Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, and derivatives thereof. The conductive polymer may be used alone or in combination of two or more types. The conductive polymer may be a copolymer of two or more types of monomers. Note that a derivative of a conductive polymer refers to a polymer having a conductive polymer as a basic skeleton. For example, a derivative of polythiophene includes poly(3,4-ethylenedioxythiophene).

[0035] The conductive polymer may contain a dopant. The dopant can be selected appropriately depending on the type of conductive polymer. Various known dopants may be used as the dopant. Examples of dopants include naphthalenesulfonic acid, p-toluenesulfonic acid, polystyrenesulfonic acid, and salts thereof. An example of a conductive polymer is poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrenesulfonic acid (PSS). In the electrolytic capacitor according to the first embodiment of the present disclosure, the conductive polymer layer is preferably formed from particles of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrenesulfonic acid (PSS) (hereinafter also referred to as PEDOT / PSS).

[0036] In the electrolytic capacitor according to the first embodiment of the present disclosure, the conductive polymer layer includes a first cationic component in addition to a conductive polymer. Examples of the first cationic component include a base component. The first cationic component may be the same as the second cationic component described below. In a solid-liquid electrolyte including a conductive polymer layer and a liquid component, the first cationic component exhibits the same function as the second cationic component contained in the liquid component. That is, the first cationic component, like the second cationic component, contributes to the dissociation of anionic and cationic components in the solid-liquid electrolyte. Therefore, even if the liquid component does not contain the second cationic component or contains only a small amount of the second cationic component, the presence of a predetermined amount or more of the first cationic component can sufficiently dissociate the anionic and cationic components in the solid-liquid electrolyte. This allows the anionic component contained in the liquid component to fully perform its function of repairing the oxide film on the anode foil.

[0037] The valence of the first cationic component is preferably monovalent. As described above, the first cationic component exhibits the same function as the second cationic component contained in the liquid component in the solid-liquid electrolyte. That is, the first cationic component exhibits the function of contributing to the dissociation state between the anionic component and the cationic component in the solid-liquid electrolyte. Therefore, by making the first cationic component monovalent, the dissociation between the anionic component and the cationic component can be more fully promoted. This allows the anionic component to more fully exert its function of repairing the oxide film on the anode foil.

[0038] The pKa of the first cationic component is preferably 10 or less. When the pKa of the first cationic component is within the above range, the basicity of the first cationic component can be prevented from becoming excessively high, which further prevents the first cationic component from reducing the ability of the dopant doped into the conductive polymer.

[0039] As described above, examples of the first cationic component that is monovalent and has a pKa of 10 or less include ammonia and N-alkylmorpholine. Therefore, it is preferable to use at least one of ammonia and N-alkylmorpholine as the first cationic component. Furthermore, it is preferable to use N-methylmorpholine as the N-alkylmorpholine.

[0040] The conductive polymer layer preferably contacts the anode foil, cathode foil, and separator over a sufficiently large contact area, thereby forming a sufficient conductive path between the anode foil and the cathode foil. As a result, the equivalent series resistance (ESR) of the electrolytic capacitor can be reduced, thereby improving the reliability of the electrolytic capacitor.

[0041] The conductive polymer layer is preferably formed on at least one selected from at least one main surface of the dielectric layer of the anode foil and at least one main surface of the cathode foil. The conductive polymer layer may also be formed within the voids of the separator (i.e., on the surface of the separator's constituent material surrounding the voids of the separator). This allows for the formation of a stronger conductive path between the anode foil and the cathode foil via the conductive polymer layer. The conductive polymer layer is preferably formed at least on the surface of the dielectric layer of the anode foil, and more preferably on both the surface of the dielectric layer and the surface of the cathode foil, and furthermore, within the voids of the separator. The conductive polymer layer is preferably formed so as to continuously connect the surface of the dielectric layer and the surface of the cathode foil.

[0042] (Exterior Body) The capacitor element may be covered with an exterior body. The exterior body includes at least one of a case and a sealing resin. The case and sealing resin are not limited, and known cases and sealing resins can be used. The sealing resin may include a thermosetting resin. Examples of thermosetting resins include epoxy resin, phenolic resin, silicone resin, melamine resin, urea resin, alkyd resin, polyurethane resin, polyimide resin, and unsaturated polyester resin. The sealing resin may include at least one selected from the group consisting of a filler, a curing agent, a polymerization initiator, and a catalyst.

[0043] <Liquid Component> The liquid component includes a nonaqueous solvent and an electrolytic solution. As the electrolytic solution, a nonaqueous electrolytic solution containing a nonaqueous solvent and a solute dissolved in the nonaqueous solvent can be used. The nonaqueous solvent and the solute can be any nonaqueous solvent and solute used in various known electrolytic capacitors. The liquid component may be a component that is liquid at room temperature (25°C) or at the temperature at which the electrolytic capacitor is used.

[0044] The non-aqueous solvent may be an organic solvent or an ionic liquid.

[0045] Examples of organic solvents include glycol compounds, sulfone compounds, and lactone compounds. Examples of glycol compounds include ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and propylene glycol (PG). Examples of sulfone compounds include sulfolane (SL), dimethyl sulfoxide (DMSO), and diethyl sulfoxide (DESO). Examples of lactone compounds include γ-butyrolactone (GBL), γ-valerolactone (GVL), and the like.

[0046] Examples of the organic solvent include carbonate compounds and monohydric, trihydric or higher alcohols. Examples of the carbonate compound include dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), ethylene carbonate (EC), propylene carbonate (PC), and fluoroethylene carbonate (FEC). Examples of the monohydric, trihydric or higher alcohol include glycerin and polyglycerin. These may be used alone or in combination of two or more.

[0047] Regarding organic solvents, if a group consisting of glycol compounds, sulfone compounds, and lactone compounds is defined as Group 1, and a group consisting of carbonate compounds and monohydric or trihydric or higher alcohols is defined as Group 2, the organic solvents belonging to Group 1 preferably account for more than 50 mass%, more preferably 60 mass% or more, and preferably 70 mass% or more of the organic solvents. All of the organic solvents may be organic solvents belonging to Group 1. That is, the organic solvents belonging to Group 1 may be the main solvent, and the organic solvents belonging to Group 2 may be the auxiliary solvent.

[0048] The liquid component preferably contains at least one organic solvent selected from the group consisting of glycol compounds, sulfone compounds, and lactone compounds. When the liquid component contains at least one of these compounds, the re-chemical conversion of the dielectric layer by the acid component contained in the liquid component can be carried out efficiently. Furthermore, since the liquid component contains a glycol compound, protons (H ＋ ) (specifically, the proton (H ＋) can be easily provided. That is, affinity with the conductive polymer layer can be improved. Furthermore, since the sulfone compound and the lactone compound are aprotic, the liquid component containing at least one of the sulfone compound and the lactone compound can suppress reaction of the liquid component with the acid component (e.g., esterification reaction). That is, the stability of the liquid component can be improved even in a high-temperature environment (e.g., an environment of 145°C). This can stabilize the characteristics of the electrolytic capacitor.

[0049] When the liquid component contains at least one organic solvent selected from the group consisting of glycol compounds, sulfone compounds, and lactone compounds, the proportion of the glycol compounds in the liquid component is preferably 40% by mass to 80% by mass, the proportion of the sulfone compounds in the liquid component is preferably 20% by mass to 60% by mass, and the proportion of the lactone compounds in the liquid component is preferably 40% by mass to 80% by mass. By containing the glycol compounds, sulfone compounds, and lactone compounds in the above numerical ranges, re-chemical conversion of the dielectric layer by the acid component contained in the liquid component can be carried out more efficiently.

[0050] From the viewpoint of donating protons to the conductive polymer, the liquid component may contain compounds other than glycol compounds, such as glycerin and polyglycerin.

[0051] The liquid component may contain water. The water content in the liquid component may be 0.1% by mass or more and 6.0% by mass or less, 0.2% by mass or more and 4.0% by mass or less, or 0.5% by mass or more and 2.0% by mass or less. By containing water in the liquid component within the above range, the repairability of the dielectric layer by the liquid component can be improved. Furthermore, when the electrolytic capacitor is used at high temperatures (for example, when used at 145°C), fluctuations in the equivalent series resistance (ESR) value can be suppressed. Note that sulfone compounds have excellent hydrolysis resistance, and therefore, when the liquid component contains a sulfone compound as described above, the hydrolysis resistance of the liquid component can be improved.

[0052] In the electrolytic capacitor according to the first embodiment of the present disclosure, the liquid component contains a second cationic component and an anionic component as solutes. The second cationic component may be a base component (base), and the anionic component may be an acid component (acid). The second cationic component may be any of the cationic components exemplified as the first cationic component. At least a portion of the first cationic component may be the same as at least a portion of the second cationic component. The proportion of the solute in the liquid component is preferably 70% by mass or less, and more preferably 50% by mass or less.

[0053] The valence of the second cationic component is preferably monovalent. The monovalent valence of the second cationic component mainly allows dissociation between the anionic component and the cationic component to proceed more sufficiently in the solid-liquid electrolyte. This allows the anionic component to more fully exhibit its function of repairing the oxide film on the anode foil. When the valence of the second cationic component is monovalent, the valence of the first cationic component is also preferably monovalent. This allows dissociation between the anionic component and the cationic component to proceed more sufficiently in the solid-liquid electrolyte. This allows the anionic component to more fully exhibit its function of repairing the oxide film on the anode foil.

[0054] The acid component may be at least one selected from the group consisting of aromatic carboxylic acids, aliphatic carboxylic acids, and salts thereof. The aromatic carboxylic acids and aliphatic carboxylic acids may be polycarboxylic acids or monocarboxylic acids. Aliphatic polycarboxylic acids may include saturated polycarboxylic acids and unsaturated polycarboxylic acids. Saturated polycarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,6-decanedicarboxylic acid, and 5,6-decanecarboxylic acid. Unsaturated polycarboxylic acids include maleic acid, fumaric acid, and itaconic acid. Aromatic polycarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, and benzoic acid. The phthalic acid may be o-phthalic acid. An aromatic monocarboxylic acid may include salicylic acid.

[0055] The polycarboxylic acid also includes alicyclic polycarboxylic acids, such as cyclohexane-1,2-dicarboxylic acid and cyclohexene-1,2-dicarboxylic acid.

[0056] Examples of monocarboxylic acids include aliphatic monocarboxylic acids and aromatic monocarboxylic acids. In this specification, the term "aromatic monocarboxylic acid" encompasses hydroxycarboxylic acids. Examples of aliphatic monocarboxylic acids include saturated monocarboxylic acids and unsaturated monocarboxylic acids. Examples of saturated monocarboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, lauric acid, myristic acid, stearic acid, and behenic acid. Examples of unsaturated monocarboxylic acids include acrylic acid, methacrylic acid, and oleic acid. Examples of aromatic monocarboxylic acids include benzoic acid, cinnamic acid, and naphthoic acid. Examples of hydroxycarboxylic acids include salicylic acid, mandelic acid, and resorcylic acid.

[0057] The aromatic carboxylic acid is preferably at least one selected from the group consisting of o-phthalic acid, salicylic acid, and benzoic acid, and the aliphatic carboxylic acid is preferably at least one selected from the group consisting of adipic acid, azelaic acid, and sebacic acid.

[0058] An inorganic acid may be used as the acid component. Examples of inorganic acids include phosphoric acid, phosphorous acid, hypophosphorous acid, alkyl phosphate esters, boric acid, fluoroboric acid, tetrafluoroboric acid, hexafluorophosphoric acid, benzenesulfonic acid, and naphthalenesulfonic acid. Alternatively, a composite compound of an organic acid and an inorganic acid may be used as the acid component. Examples of such composite compounds include dicarboxylic acid derivatives such as borodiglycolic acid, borodisalic acid, and borodisalicylic acid.

[0059] The base component may be a compound having an alkyl-substituted amidine group, such as an imidazole compound, a benzimidazole compound, or an alicyclic amidine compound (a pyrimidine compound, an imidazoline compound). Specifically, 1,8-diazabicyclo[5,4,0]undecene-7; 1,5-diazabicyclo[4,3,0]nonene-5; 1,2-dimethylimidazolinium; 1,2,4-trimethylimidazoline; 1-methyl-2-ethylimidazoline; 1,4-dimethyl-2-ethylimidazoline; 1-methyl-2-heptylimidazoline; 1-methyl-2-(3'heptyl)imidazoline; 1-methyl-2-dodecylimidazoline; 1,2-dimethyl-1,4,5,6-tetrahydropyrimidine; 1-methylimidazole; or 1-methylbenzimidazole is preferred. By using these, the electrolytic capacitor can be made to have excellent impedance characteristics.

[0060] The base component may be a quaternary salt of a compound having an alkyl-substituted amidine group, such as an imidazole compound, a benzimidazole compound, or an alicyclic amidine compound (a pyrimidine compound, an imidazoline compound) quaternized with an alkyl group or an arylalkyl group having 1 to 11 carbon atoms. Specifically, 1-methyl-1,8-diazabicyclo[5,4,0]undecene-7; 1-methyl-1,5-diazabicyclo[4,3,0]nonene-5; 1,2,3-trimethylimidazolinium; 1,2,3,4-tetramethylimidazolinium; 1,2-dimethyl-3-ethyl-imidazolinium; 1,3,4-trimethyl-2-ethylimidazolinium; 1,3-dimethyl-2-heptylimidazolinium; 1,3-dimethyl-2-(3'heptyl)imidazolinium; 1,3-dimethyl-2-dodecylimidazolinium; 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidium; 1,3-dimethylimidazolium; 1-methyl-3-ethylimidazolium; 1,3-dimethylbenzimidazolium is preferred. By using these materials, the electrolytic capacitor can be made to have excellent impedance characteristics.

[0061] Tertiary amines may be used as the base component. Examples of tertiary amines include trialkylamines and phenyl group-containing amines. Examples of trialkylamines include trimethylamine, dimethylethylamine, methyldiethylamine, triethylamine, dimethyl-n-propylamine, dimethylisopropylamine, methylethyl-n-propylamine, methylethylisopropylamine, diethyl-n-propylamine, diethylisopropylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, and tri-tert-butylamine. Examples of phenyl group-containing amines include dimethylphenylamine, methylethylphenylamine, and diethylphenylamine. From the viewpoint of increasing conductivity, trialkylamines are preferably used, and among trialkylamines, it is preferable to use at least one selected from the group consisting of trimethylamine, dimethylethylamine, methyldiethylamine, and triethylamine. Examples of the base component may include secondary amines such as dialkylamines, primary amines such as monoalkylamines, and ammonia.

[0062] A heterocyclic amine may be used as the base component. Examples of heterocyclic amines include morpholines, and examples of morpholines include morpholine and morpholine derivatives. Specific examples include morpholine, N-alkylmorpholine, and N-hydroxyalkylmorpholine, and examples of N-alkylmorpholine include N-methylmorpholine, N-butylmorpholine, and 4-isobutylmorpholine. Furthermore, examples of heterocyclic amines that can be used include pyridine and imidazole.

[0063] The pKa of the second cationic component, such as a basic component, is preferably 11 or less. Examples of second cationic components having a pKa of 11 or less include triethylamine, dimethylethylamine, morpholine, and ammonia. That is, it is preferable to use at least one selected from the group consisting of triethylamine, dimethylethylamine, morpholine, and ammonia as the second cationic component. By using a second cationic component having a pKa of 11 or less, the basicity of the second cationic component can be prevented from becoming excessively high. This further prevents the second cationic component from reducing the performance of the dopant doped into the conductive polymer. As a result, various properties of the electrolytic capacitor can be further improved. For example, in an electrolytic capacitor, a decrease in capacitance can be further suppressed, and an increase in equivalent series resistance can be further suppressed.

[0064] The liquid component may contain a salt of an acid component and a base component. The salt may be an inorganic salt or an organic salt. An organic salt is a salt in which at least one of the anion and the cation contains an organic substance. Examples of organic salts include trimethylamine maleate, triethylamine borodisalicylate, ethyldimethylamine phthalate, mono-1,2,3,4-tetramethylimidazolinium phthalate, and mono-1,3-dimethyl-2-ethylimidazolinium phthalate. The organic salt may be an amine salt of a long-chain dibasic carboxylic acid. An example of an amine salt of a long-chain dibasic carboxylic acid is diethylamine 2-butyloctanedioate (2BA).

[0065] The ionic liquid is synonymous with a salt in a molten state (molten salt), and is an ionic substance that is liquid at, for example, 25°C.

[0066] Examples of cations that constitute ionic liquids include cations of nitrogen-containing heterocycles (imidazolium, pyrrolidinium, piperidinium, pyridinium, morpholinium, etc.), ammonium, phosphonium, sulfonium, and derivatives thereof (e.g., substituted compounds having a substituent such as an alkyl group). The cation may also be an organic cation.

[0067] The anions that constitute the ionic liquid include hydrogen sulfate ions (HSO ４ － ), sulfate ions (SO ４ ２－ , -SO ４ － ), carboxylate anion (-COO － ), nitrate anion, sulfonate anion (-SO ３ － ), phosphonate anion (PO ３ ２－ , -HPO ３ － ) and the like. Acids capable of generating these anions include sulfuric acid, sulfuric acid monoesters (methyl sulfate, etc.), carboxylic acids (acetic acid, lactic acid, benzoic acid, trifluoromethane acetic acid, etc.), nitric acid, sulfonic acids (methanesulfonic acid, trifluoromethanesulfonic acid, bis(trifluoromethylsulfonyl)imide anion, etc.), phosphonic acids (diethylphosphonic acid, etc.), or derivatives thereof (e.g., substituted compounds having a substituent such as an alkyl group, a halogenated alkyl group, or a halogen atom). The anion may contain a fluorine atom. Examples of fluorine atom-containing anions include the above-mentioned trifluoromethane acetic acid, trifluoromethanesulfonic acid, bis(trifluoromethylsulfonyl)imide anion, and derivatives thereof.

[0068] Specific examples of ionic liquids include 1-butyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, and 1-ethyl-3-methylimidazolium diethylphosphonate.

[0069] The liquid component may contain a polymer compound. Examples of the polymer compound include polyalkylene glycol, polyalkylene glycol derivatives, and compounds in which at least one hydroxyl group of a polyhydric alcohol is substituted with polyalkylene glycol (including derivatives). Specific examples include polyethylene glycol (PEG), polyethylene glycol glyceryl ether, polyethylene glycol diglyceryl ether, polyethylene glycol sorbitol ether, polypropylene glycol, polypropylene glycol diglyceryl ether, polypropylene glycol sorbitol ether, and polybutylene glycol.

[0070] The polyalkylene glycol may be a copolymer (random copolymer, block copolymer, random block copolymer, or the like), such as a copolymer of ethylene glycol and propylene glycol, a copolymer of ethylene glycol and butylene glycol, or a copolymer of propylene glycol and butylene glycol.

[0071] The polymer compound may be a copolymer having ethylene oxide (EO) units and propylene oxide (PO) units. The copolymer includes a copolymer of EO and PO (EO-PO copolymer) and a derivative thereof. These may be used alone or in combination of two or more. The copolymer may be crosslinked with a crosslinking agent. The derivative may be a copolymer obtained by converting a hydroxyl group (—OH) that an EO-PO copolymer normally has at its terminal into an acrylic group (O—CO—CH═CH ２ ) or the like. When the entire EO-PO copolymer is taken as 1 mole, the molar ratio of EO units to PO units is preferably EO:PO=0.9:0.1 to 0.5:0.5. That is, the EO-PO copolymer preferably contains the same amount of EO units as the PO units. This makes it possible to prevent the EO-PO copolymer contained in the liquid component from permeating through the sealing member in an electrolytic capacitor in which a capacitor element is housed in a bottomed case and the opening of the bottomed case is sealed with a sealing member (such as sealing rubber).

[0072] In the electrolytic capacitor according to the embodiment of the present disclosure, the mass average molecular weight Mw of the polymer compound may be 200 or more, 300 or more, 400 or more, or 500 or more. The mass average molecular weight Mw of the polymer compound may be 5000 or less, 4000 or less, 3000 or less, 2000 or less, or 1000 or less.

[0073] The mass average molecular weight Mw of a polymer compound is a polystyrene-equivalent value measured by gel permeation chromatography (GPC). GPC measurement is usually performed using a polystyrene gel column and water / methanol (volume ratio 8 / 2) as the mobile phase.

[0074] Measurement by GPC is carried out using, for example, a column consisting of two connected Shodex OHpak SB804HQ and SB8025HQ columns, with 50 mM NaNO ３ The analysis can be carried out using an aqueous solution as an eluent, an RI detector, a column temperature of 40° C., a flow rate of the eluent of 0.7 mL / min, and an analysis time of 40 min.

[0075] [Second Embodiment] An electrolytic capacitor according to a second embodiment of the present disclosure includes a capacitor element and a liquid component. In the electrolytic capacitor according to the second embodiment of the present disclosure, the capacitor element includes an anode foil having a dielectric layer, a cathode foil arranged so as to face the dielectric layer, a separator interposed between the anode foil and the cathode foil, and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator. In the electrolytic capacitor according to the second embodiment of the present disclosure, the conductive polymer layer includes a conductive polymer, and the solid-liquid electrolyte including the conductive polymer layer and the liquid component includes a first cation component and an anion component. In the electrolytic capacitor according to the second embodiment of the present disclosure, the conductive polymer layer includes the first cation component, and the liquid component includes an anion component. In the electrolytic capacitor according to the second embodiment of the present disclosure, in the solid-liquid electrolyte, when the ratio of the number of moles of the first cation component to the mass of the conductive polymer is A (mol / kg) and the ratio of the number of moles of the anion component to the mass of the conductive polymer is B (mol / kg), the ratio A and the ratio B satisfy the relationship 0.20≦A / B≦1.01.

[0076] As described above, the electrolytic capacitor according to the first embodiment and the electrolytic capacitor according to the second embodiment differ mainly in that, in the electrolytic capacitor according to the first embodiment, the solid-liquid electrolyte contains three ionic components: a first cation component, a second cation component, and an anion component, whereas, in the electrolytic capacitor according to the second embodiment, the solid-liquid electrolyte contains two ionic components: a first cation component and an anion component.

[0077] Even if the liquid component does not contain the second cationic component, if the ratio A (mol / kg) of the number of moles of the first cationic component to the mass of the conductive polymer and the ratio B (mol / kg) of the number of moles of the anionic component to the mass of the conductive polymer in the solid-liquid electrolyte satisfy the appropriate relationship as described above, the electrolytic capacitor according to the second embodiment, like the electrolytic capacitor according to the first embodiment, can simultaneously suppress a decrease in capacity, an increase in leakage current, and an increase in equivalent series resistance even after the reflow process.

[0078] In the electrolytic capacitor according to the second embodiment, the ratios A and B preferably satisfy the relationship 0.20≦A / B<1. That is, in the solid-liquid electrolyte, the number of moles of the first cation component is preferably smaller than the number of moles of the anion component. By satisfying this relationship, it is possible to further suppress the occurrence of undoping in the conductive polymer. This further suppresses the occurrence of defects in the structure of the conductive polymer.

[0079] A specific configuration of an electrolytic capacitor according to an embodiment of the present disclosure will be described below with reference to Figures 1 and 2. Figure 1 is a cross-sectional view that schematically illustrates an electrolytic capacitor 100 according to an embodiment of the present disclosure, and Figure 2 is a schematic view that includes a portion of a capacitor element 10 included in the electrolytic capacitor 100.

[0080] Electrolytic capacitor 100 includes capacitor element 10, bottomed case 101 that houses capacitor element 10, sealing member 102 (e.g., a sealing rubber) that closes the opening of bottomed case 101, seat plate 103 that covers sealing member 102, seat plate 103 that is disposed outside bottomed case 101 so as to cover sealing member 102 from the open side of bottomed case 101, a pair of lead wires 104A, 104B that extend from sealing member 102 and pass through seat plate 103, and a pair of lead tabs 105A, 105B that connect each of the pair of lead wires 104A, 104B to electrodes of the capacitor element (e.g., an anode foil 11 and a cathode foil 12, which will be described later). The vicinity of the open end of bottomed case 101 is drawn to be recessed inward, and the open end of bottomed case 101 is curled to be crimped to sealing member 102. In the example shown in FIG. 1, lead wire 104A is connected to an electrode of the capacitor element via lead tab 105A, and lead wire 104B is connected to an electrode of the capacitor element via lead tab 105B.

[0081] The sealing member 102 is formed of an elastic material containing a rubber component. Examples of the rubber component include butyl rubber (IIR), nitrile rubber (NBR), ethylene propylene rubber, ethylene propylene diene rubber (EPDM), chloroprene rubber (CR), isoprene rubber (IR), Hypalon (trademark) rubber, silicone rubber, and fluororubber. The sealing member 102 may contain fillers such as carbon black and silica.

[0082] Capacitor element 10 is configured as, for example, a wound body as shown in FIG. 2. The wound body includes anode foil 11 connected to lead tab 105A, cathode foil 12 connected to lead tab 105B, and separator 13. Capacitor element 10 includes a conductive polymer layer (not shown). Note that electrolytic capacitor 100 shown in FIG. 1 includes capacitor element 10 shown in FIG. 2, and is therefore referred to as a wound-type electrolytic capacitor.

[0083] The anode foil 11 and the cathode foil 12 are wound with a separator 13 interposed therebetween to form a wound body. The outermost periphery of this wound body is fixed with a stop tape 14. Note that Fig. 2 shows the wound body in a partially unfolded state before the outermost periphery is fixed with the stop tape 14.

[0084] The electrolytic capacitor according to the present disclosure may include at least one capacitor element, or may include a plurality of capacitor elements, the number of which is determined appropriately depending on the intended use.

[0085] Although a wound-type electrolytic capacitor has been described in FIGS. 1 and 2, the electrolytic capacitor according to the embodiment of the present disclosure is not limited to this, and may be a chip-type electrolytic capacitor or a stacked-type electrolytic capacitor.

[0086] [Method for Manufacturing an Electrolytic Capacitor] An example of a method for manufacturing an electrolytic capacitor according to an embodiment of the present disclosure includes the steps of: (a) preparing an anode foil having a dielectric layer, a cathode foil, and a separator; (b) applying a polymer dispersion containing a conductive polymer and a dopant dispersed in a liquid medium to the surface of the dielectric layer, at least one main surface of the cathode foil, and voids in the separator, the polymer dispersion including a first cationic component (hereinafter also referred to as a first cationic component-containing polymer dispersion); (c) forming a conductive polymer layer on the one main surface and in the voids in the separator by removing at least a portion of the liquid medium from the first cationic component-containing polymer dispersion; (d) forming a capacitor element by disposing a separator between the anode foil and the cathode foil; and (e) filling the voids in the capacitor element with a liquid component including a second cationic component and an anionic component. In the method for manufacturing an electrolytic capacitor according to an embodiment of the present disclosure, the steps (a) to (e) are preferably performed in this order.

[0087] <Step (a)> The step of preparing an anode foil, a cathode foil, and a separator each having a dielectric layer is not particularly limited. The materials of the anode foil, the cathode foil, and the separator are also not particularly limited. For example, the above-described materials can be used as the anode foil, the cathode foil, and the separator.

[0088] <Step (b)> In step (b), the first cationic component-containing polymer dispersion may be applied to the surface of the dielectric layer and the separator, or to at least one main surface of the cathode foil and the separator. Alternatively, the first cationic component-containing polymer dispersion may be applied to the surface of the dielectric layer, at least one main surface of the cathode foil, and the separator. When dielectric layers are formed on both main surfaces of the anode foil, the first cationic component-containing polymer dispersion may be applied to the surfaces of the dielectric layers formed on both main surfaces of the anode foil. The first cationic component-containing polymer dispersion may also be applied to both main surfaces of the cathode foil. A conductive polymer layer is formed at the location where the first cationic component-containing polymer dispersion is applied. The first cationic component may be any of those described above.

[0089] Examples of methods for applying the first cationic component-containing polymer dispersion include coating. Coating can be performed by various known methods. Examples of coating include coating using a coater, spray coating, and coating by immersing the object to be coated in the first cationic component-containing polymer dispersion. Examples of coating using a coater include gravure coating and die coating. Note that an example of the liquid medium is water.

[0090] <Step (c)> In step (c), the method for removing at least a portion of the liquid medium from the first cation component-containing polymer dispersion is not particularly limited. The liquid medium is preferably removed by at least heating. The liquid medium may be removed by heating under reduced pressure. When the liquid medium is water, the liquid medium is preferably removed by heating the liquid medium to 100°C or higher.

[0091] In addition, when the electrolytic capacitor is a wound-type electrolytic capacitor 100 as shown in FIG. 1, a conductive polymer layer can be formed by impregnating a capacitor element 10 configured as a wound body as shown in FIG. 2 with a first cation component-containing polymer dispersion, and then heating the capacitor element 10 at a predetermined temperature.

[0092] <Step (d)> In step (d), a conductive polymer layer is formed on the surface of the dielectric layer, on at least one main surface of the cathode foil, and on a separator, and then the separator is disposed between the anode foil and the cathode foil to form a capacitor element (specifically, a capacitor element including a conductive polymer layer). This step is also a step in which the anode foil and the cathode foil are laminated with the separator interposed therebetween.

[0093] The method for forming the capacitor element is not particularly limited. The capacitor element may be formed by any known method. The capacitor element may be a wound body as shown in Fig. 2. In the wound body as shown in Fig. 2, the anode foil, the cathode foil, and the separator are stacked in the radial direction of the wound body.

[0094] A capacitor element may be formed by stacking flat anode foils, flat cathode foils, and flat separators in one direction. For example, a capacitor element may be formed by stacking multiple anode foils, multiple cathode foils, and multiple separators in one direction. An electrolytic capacitor including such a stacked capacitor element is called a stacked electrolytic capacitor. In a typical example of a stack, the anode foils and cathode foils are arranged alternately, with separators disposed between the anode foils and cathode foils.

[0095] <Step (e)> The method for filling the voids in the capacitor element with the liquid component is not particularly limited. For example, the voids in the capacitor element may be filled with the liquid component by impregnating at least a portion of the capacitor element with a liquid component containing a second cationic component and an anionic component. Note that the second cationic component and the anionic component described above can be used.

[0096] As described above, steps (a) to (e) are performed to form a capacitor element having a conductive polymer layer containing a first cationic component and a liquid component containing a second cationic component and an anionic component. The capacitor element is then encapsulated in an exterior case (case) as needed. In this manner, an electrolytic capacitor according to an embodiment of the present disclosure is manufactured.

[0097] Although the above describes an example in which a conductive polymer layer is formed on the surface of the dielectric layer and at least one main surface of the cathode foil, and on the separator before stacking the anode foil and the cathode foil with the separator interposed therebetween, the example in which a conductive polymer layer is formed is not limited to this. The conductive polymer layer may be formed after stacking the anode foil and the cathode foil with the separator interposed therebetween. For example, after obtaining a wound body in which the anode foil and the cathode foil are stacked with the separator interposed therebetween, the wound body may be immersed in a first cation component-containing polymer dispersion to form a conductive polymer layer on the surface of the dielectric layer, at least one main surface of the cathode foil, and on the separator.

[0098] (Additional Note) The above description discloses the following techniques. (Technology 1) An electrolytic capacitor comprising a capacitor element and a liquid component, wherein the capacitor element comprises: an anode foil having a dielectric layer; a cathode foil disposed so as to face the dielectric layer; a separator interposed between the anode foil and the cathode foil; and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, wherein the conductive polymer layer comprises a conductive polymer, and a solid-liquid electrolyte comprising the conductive polymer layer and the liquid component comprises a first cationic component, a second cationic component, and an anionic component, wherein the conductive polymer layer comprises the first cationic component, and the liquid component comprises the second cationic component and the anionic component, and in the solid-liquid electrolyte, a ratio of the number of moles of the first cationic component to the mass of the conductive polymer is A (mol / kg), a ratio of the number of moles of the anionic component to the mass of the conductive polymer is B (mol / kg), and a ratio of the number of moles of the second cationic component to the mass of the conductive polymer is C (mol / kg), The electrolytic capacitor, wherein the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B≦1.01. (Technology 2) An electrolytic capacitor comprising: a capacitor element; and a liquid component, wherein the capacitor element comprises: an anode foil having a dielectric layer; a cathode foil disposed opposite the dielectric layer; a separator interposed between the anode foil and the cathode foil; and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, wherein the conductive polymer layer comprises a conductive polymer, and a solid-liquid electrolyte comprising the conductive polymer layer and the liquid component comprises a first cation component and an anion component, wherein the conductive polymer layer comprises the first cation component, and the liquid component comprises the anion component, wherein, in the solid-liquid electrolyte, a ratio of the number of moles of the first cation component to the mass of the conductive polymer is A (mol / kg) and a ratio of the number of moles of the anion component to the mass of the conductive polymer is B (mol / kg), the ratio A and the ratio B satisfy the relationship 0.20≦A / B≦1.01.(Technology 3) The electrolytic capacitor according to Technology 1, wherein the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B<1. (Technology 4) The electrolytic capacitor according to Technology 2, wherein the ratio A and the ratio B satisfy the relationship 0.20≦A / B<1. (Technology 5) The electrolytic capacitor according to Technology 1 or 3, wherein the ratio A is in the range of 1 mol / kg to 30 mol / kg, the ratio B is in the range of 25 mol / kg to 45 mol / kg, and the ratio C is in the range of 1 mol / kg to 25 mol / kg. (Technology 6) The electrolytic capacitor according to Technology 1, 3, or 5, wherein the valences of the first cationic component and the second cationic component are both 1. (Technology 7) The electrolytic capacitor according to any one of Technology 1 to 6, wherein the pKa of the first cationic component is 10 or less. (Technology 8) The electrolytic capacitor according to Technology 1, 3, 5, 6, or 7, wherein the pKa of the second cation component is 11 or less. (Technology 9) The electrolytic capacitor according to any one of Technology 1 to 8, wherein the anion component is at least one selected from the group consisting of aromatic carboxylic acids, aliphatic carboxylic acids, and salts thereof. (Technology 10) The electrolytic capacitor according to Technology 9, wherein the aromatic carboxylic acid is at least one selected from the group consisting of o-phthalic acid, salicylic acid, and benzoic acid. (Technology 11) The electrolytic capacitor according to Technology 9, wherein the aliphatic carboxylic acid is at least one selected from the group consisting of adipic acid, azelaic acid, and sebacic acid.

[0099] While the present invention has been described in terms of presently preferred embodiments, such disclosure should not be interpreted as limiting. Various changes and modifications will no doubt become apparent to those skilled in the art to which the present invention pertains upon reading the above disclosure. It is therefore intended that the appended claims be interpreted to cover all changes and modifications that do not depart from the true spirit and scope of the invention.

[0100] Hereinafter, the present disclosure will be specifically described based on examples and comparative examples, but the present disclosure is not limited to the following examples.

[0101] [Example 1] (A) Preparation of Components (A-1) Anode Foil Both main surfaces of an aluminum foil (thickness 100 μm) were etched to obtain an aluminum foil with roughened main surfaces. After etching, both main surfaces of the aluminum foil were subjected to a chemical conversion treatment to form a dielectric layer on both main surfaces. In this way, an anode foil with a dielectric layer formed on both main surfaces was obtained.

[0102] (A-2) Cathode Foil Both main surfaces of an aluminum foil (thickness 50 μm) were subjected to an etching treatment to obtain a cathode foil with both main surfaces roughened.

[0103] (A-3) Separator A nonwoven fabric (thickness: 50 μm) was prepared as a separator. The nonwoven fabric was composed of 50% by mass of synthetic fibers (25% by mass of polyester fibers and 25% by mass of aramid fibers) and 50% by mass of cellulose, and contained polyacrylamide as a paper strength agent. The density of the nonwoven fabric was 0.35 g / cm ３ It was.

[0104] (B) Preparation of First Cationic Component-Containing Polymer Dispersion 3,4-ethylenedioxythiophene and poly(4-styrenesulfonic acid) (PSS, mass-average molecular weight Mw 100,000; dopant) were dissolved in ion-exchanged water to prepare a mixed solution. Next, while stirring this mixed solution, an oxidizing agent (iron(III) sulfate and ammonium persulfate) dissolved in ion-exchanged water was added to the mixed solution to carry out a polymerization reaction. After the polymerization reaction, the resulting reaction solution was dialyzed to remove unreacted monomer and excess oxidizing agent. This resulted in a polymer dispersion doped with PSS (PEDOT / PSS). Next, 0.0044 mmol (1.47 mol per kg of PEDOT / PSS) of ammonia was added to this polymer dispersion as the first cationic component to obtain a first cationic component-containing polymer dispersion.

[0105] (C) Fabrication of a Wound Body The anode foil, cathode foil, and separator were each cut to have predetermined planar dimensions. An anode lead tab was connected to the anode foil, and a cathode lead tab was connected to the cathode foil. Next, the anode foil and cathode foil were wound with the separator interposed therebetween to obtain a wound body. At this time, the ends of the outer surface of the wound body were fixed with winding tape. An anode lead wire was connected to the end of the anode lead tab, and a cathode lead wire was connected to the end of the cathode lead tab. The wound body obtained as described above was again subjected to chemical conversion treatment to form a dielectric layer on the end surface of the anode foil. Specifically, dielectric layers were formed on the upper and lower end surfaces of the wound body as shown in FIG. 2.

[0106] (D) Formation of Conductive Polymer Layer The wound body was immersed in a first cationic component-containing polymer dispersion contained in a designated container in a reduced pressure atmosphere (40 kPa) for 5 minutes. The first cationic component-containing polymer dispersion was almost entirely (98% by volume or more) impregnated into the wound body. The wound body impregnated with the first cationic component-containing polymer dispersion was then dried in a drying oven at 150°C for 20 minutes to form a conductive polymer layer covering at least a portion of the dielectric layer. In other words, a wound body containing a conductive polymer layer (hereinafter also referred to as a wound body containing a conductive polymer layer) was obtained.

[0107] (E) Impregnation with Liquid Component A mixed solvent containing polyethylene glycol (PEG), ethylene glycol (EG), and sulfolane (SL) was prepared. The volume ratio of PEG, EG, and SL in this mixed solvent was PEG:EG:SL = 30:20:50. Phthalic acid (FT) as the anion component and dimethylethylamine (DEA) as the second cation component were added to this mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.68 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 23.74 mol per kg of PEDOT / PSS. Next, the wound body containing the conductive polymer layer was immersed in this electrolyte solution for 5 minutes. Note that the wound body containing the conductive polymer layer was almost entirely (98% by volume or more) immersed in the electrolyte solution. As a result, a capacitor element according to Example 1 was obtained. Furthermore, when the ratio of the number of moles of the first cation component to the mass of the conductive polymer was A (mol / kg), the ratio of the number of moles of the anion component to the mass of the conductive polymer was B (mol / kg), and the ratio of the number of moles of the second cation component to the mass of the conductive polymer was C (mol / kg), (A+C) / B was 0.85.

[0108] The capacitor element according to Example 1 was sealed to produce an electrolytic capacitor as shown in FIG. 1 . Then, an aging treatment was performed at 95°C for 90 minutes while applying a voltage. In this manner, the electrolytic capacitor according to Example 1 was obtained. Note that an elastic member containing butyl rubber as a rubber component was used as the sealing member for sealing the capacitor element. Note that 60 electrolytic capacitors were produced. The same applies to each of the following examples.

[0109] [Example 2] An electrolytic capacitor according to Example 2 was obtained in the same manner as in Example 1, except that an electrolyte solution (liquid component) was prepared by adding phthalic acid (FT) as the anion component and dimethylethylamine (DEA) as the second cation component to the mixed solvent in the molar ratios shown in Table 1A below. Specifically, phthalic acid (FT) was added in an amount of 32.89 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 16.44 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 2, (A + C) / B was 0.54.

[0110] [Example 3] An electrolytic capacitor according to Example 3 was obtained in the same manner as in Example 1, except that 0.0132 mmol (4.41 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component when obtaining the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 3, (A+C) / B was 0.95.

[0111] [Example 4] An electrolytic capacitor according to Example 4 was obtained in the same manner as in Example 2, except that 0.0132 mmol (4.41 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 4, (A+C) / B was 0.63.

[0112] [Example 5] An electrolytic capacitor according to Example 5 was obtained in the same manner as in Example 1, except that phthalic acid (FT) as the anion component and dimethylethylamine (DEA) as the second cation component were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 38.43 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 3.84 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 5, (A + C) / B was 0.21.

[0113] [Example 6] An electrolytic capacitor according to Example 6 was obtained in the same manner as in Example 2, except that 0.0229 mmol (7.65 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 6, (A+C) / B was 0.73.

[0114] [Example 7] The electrolytic capacitor of Example 7 was obtained in the same manner as in Example 5, except that 0.0229 mmol of ammonia (7.65 mol per kg of PEDOT / PSS) was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor of Example 7, (A+C) / B was 0.30.

[0115] [Example 8] The electrolytic capacitor of Example 8 was obtained in the same manner as in Example 2, except that 0.0441 mmol (14.71 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor of Example 8, (A+C) / B was 0.95.

[0116] [Example 9] An electrolytic capacitor according to Example 9 was obtained in the same manner as in Example 5, except that 0.0441 mmol (14.71 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 9, (A+C) / B was 0.48.

[0117] [Example 10] An electrolytic capacitor according to Example 10 was obtained in the same manner as in Example 8, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the molar ratio shown in Table 1A below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per 1 kg of PEDOT / PSS. In addition, the A / B ratio for the electrolytic capacitor according to Example 10 was 0.37.

[0118] [Example 11] An electrolytic capacitor according to Example 11 was obtained in the same manner as in Example 5, except that 0.0882 mmol (29.41 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 11, (A+C) / B was 0.87.

[0119] [Example 12] An electrolytic capacitor according to Example 12 was obtained in the same manner as in Example 11, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the molar ratio shown in Table 1A below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In addition, the A / B ratio for the electrolytic capacitor according to Example 12 was 0.73.

[0120] [Example 13] An electrolytic capacitor according to Example 13 was obtained in the same manner as in Example 8, except that triethylamine (TEA) was used as the second cationic component, and phthalic acid (FT) and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 30.76 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 15.38 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 13, (A + C) / B was 0.98.

[0121] [Example 14] An electrolytic capacitor according to Example 14 was obtained in the same manner as in Example 13, except that phthalic acid (FT) and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 37.82 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 3.78 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 14, (A + C) / B was 0.49.

[0122] Example 15: An electrolytic capacitor according to Example 15 was obtained in the same manner as in Example 13, except that 1,2,3,4-tetramethylimidazolinium (TMI) was used as the second cation component, and phthalic acid (FT) and 1,2,3,4-tetramethylimidazolinium (TMI) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.02 mol per kg of PEDOT / PSS, and 1,2,3,4-tetramethylimidazolinium (TMI) was added in an amount of 14.51 mol per kg of PEDOT / PSS. Furthermore, in the electrolytic capacitor according to Example 15, (A+C) / B was 1.01.

[0123] Example 16 An electrolytic capacitor according to Example 16 was obtained in the same manner as in Example 15, except that phthalic acid (FT) and 1,2,3,4-tetramethylimidazolinium (TMI) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 37.27 mol per kg of PEDOT / PSS, and 1,2,3,4-tetramethylimidazolinium (TMI) was added in an amount of 3.73 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 16, (A+C) / B was 0.49.

[0124] [Example 17] An electrolytic capacitor according to Example 17 was obtained in the same manner as in Example 2, except that 0.0445 mmol (14.83 mol per kg of PEDOT / PSS) of methylmorpholine (MHP) was used as the first cationic component when obtaining the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Example 17, (A+C) / B was 0.95.

[0125] Example 18 An electrolytic capacitor according to Example 18 was obtained in the same manner as in Example 17, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 38.43 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 3.84 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 18, (A+C) / B was 0.49.

[0126] [Example 19] An electrolytic capacitor according to Example 19 was obtained in the same manner as in Example 17, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the amount shown in Table 1A below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In addition, the A / B ratio for the electrolytic capacitor according to Example 19 was 0.37.

[0127] Example 20: An electrolytic capacitor according to Example 20 was obtained in the same manner as in Example 8, except that methylmorpholine (MHP) was used as the second cation component, and phthalic acid (FT) and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 30.76 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 15.38 mol per kg of PEDOT / PSS. Furthermore, in the electrolytic capacitor according to Example 20, (A+C) / B was 0.98.

[0128] Example 21 An electrolytic capacitor according to Example 21 was obtained in the same manner as in Example 20, except that phthalic acid (FT) and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 37.82 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 3.78 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 21, (A+C) / B was 0.49.

[0129] [Example 22] An electrolytic capacitor according to Example 22 was obtained in the same manner as in Example 13, except that azelaic acid was used as the anion component, and azelaic acid and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1A below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 33.61 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 3.36 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Example 22, (A + C) / B was 0.54.

[0130] [Example 23] An electrolytic capacitor according to Example 23 was obtained in the same manner as in Example 22, except that the electrolyte solution (liquid component) contained only azelaic acid as the anion component in the amount shown in Table 1A below. Specifically, the electrolyte solution (liquid component) contained 35.42 mol of azelaic acid per kg of PEDOT / PSS. In addition, the A / B ratio for the electrolytic capacitor according to Example 23 was 0.42.

[0131] Example 24: The electrolytic capacitor of Example 24 was obtained in the same manner as Example 22, except that methylmorpholine (MHP) was used as the second cation component, and azelaic acid and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1A below to prepare the electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 33.61 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 3.36 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor of Example 24, (A + C) / B was 0.54.

[0132] Comparative Example 1 An electrolytic capacitor according to Comparative Example 1 was obtained in the same manner as in Example 1, except that the first cationic component was not used when obtaining the polymer dispersion, and phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. Furthermore, the C / B ratio for the electrolytic capacitor according to Comparative Example 1 was 1.10.

[0133] [Comparative Example 2] An electrolytic capacitor according to Comparative Example 2 was obtained in the same manner as in Comparative Example 1, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per 1 kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per 1 kg of PEDOT / PSS. In addition, the C / B ratio for the electrolytic capacitor according to Comparative Example 2 was 1.00.

[0134] [Comparative Example 3] An electrolytic capacitor according to Comparative Example 3 was obtained in the same manner as in Comparative Example 1, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 28.74 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 25.87 mol per kg of PEDOT / PSS. In addition, the C / B ratio for the electrolytic capacitor according to Comparative Example 3 was 0.90.

[0135] [Comparative Example 4] An electrolytic capacitor according to Comparative Example 4 was obtained in the same manner as in Comparative Example 1, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 4, (A+C) / B was 1.15.

[0136] [Comparative Example 5] An electrolytic capacitor according to Comparative Example 5 was obtained in the same manner as in Example 1, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 5, (A+C) / B was 1.05.

[0137] [Comparative Example 6] An electrolytic capacitor according to Comparative Example 6 was obtained in the same manner as in Example 1, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 38.43 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 3.84 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 6, (A+C) / B was 0.14.

[0138] [Comparative Example 7] An electrolytic capacitor according to Comparative Example 7 was obtained in the same manner as in Comparative Example 4, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the amount shown in Table 1B below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 7, the A / B ratio was 0.04.

[0139] [Comparative Example 8] An electrolytic capacitor according to Comparative Example 8 was obtained in the same manner as in Example 3, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 8, (A+C) / B was 1.26.

[0140] [Comparative Example 9] An electrolytic capacitor according to Comparative Example 9 was obtained in the same manner as in Example 3, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 9, (A+C) / B was 1.16.

[0141] [Comparative Example 10] An electrolytic capacitor according to Comparative Example 10 was obtained in the same manner as in Comparative Example 8, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the amount shown in Table 1B below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 10, the A / B ratio was 0.11.

[0142] [Comparative Example 11] An electrolytic capacitor according to Comparative Example 11 was obtained in the same manner as in Example 6, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 11, (A + C) / B was 1.38.

[0143] [Comparative Example 12] An electrolytic capacitor according to Comparative Example 12 was obtained in the same manner as in Example 6, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 12, (A + C) / B was 1.27.

[0144] [Comparative Example 13] An electrolytic capacitor according to Comparative Example 13 was obtained in the same manner as in Example 6, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.68 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 23.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 13, (A + C) / B was 1.06.

[0145] [Comparative Example 14] An electrolytic capacitor according to Comparative Example 14 was obtained in the same manner as in Comparative Example 11, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the amount shown in Table 1B below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In the electrolytic capacitor according to Comparative Example 14, the A / B ratio was 0.19.

[0146] [Comparative Example 15] An electrolytic capacitor according to Comparative Example 15 was obtained in the same manner as in Example 8, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 15, (A + C) / B was 1.64.

[0147] [Comparative Example 16] An electrolytic capacitor according to Comparative Example 16 was obtained in the same manner as in Example 8, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 16, (A+C) / B was 1.53.

[0148] [Comparative Example 17] An electrolytic capacitor according to Comparative Example 17 was obtained in the same manner as in Example 8, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.68 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 23.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 17, (A + C) / B was 1.30.

[0149] [Comparative Example 18] An electrolytic capacitor according to Comparative Example 18 was obtained in the same manner as in Example 11, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 18, (A + C) / B was 2.19.

[0150] [Comparative Example 19] An electrolytic capacitor according to Comparative Example 19 was obtained in the same manner as in Example 11, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 19, (A+C) / B was 2.06.

[0151] [Comparative Example 20] An electrolytic capacitor according to Comparative Example 20 was obtained in the same manner as in Example 11, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.68 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 23.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 20, (A+C) / B was 1.79.

[0152] [Comparative Example 21] An electrolytic capacitor according to Comparative Example 21 was obtained in the same manner as in Example 11, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1B below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 32.89 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 16.44 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 21, (A + C) / B was 1.39.

[0153] [Comparative Example 22] An electrolytic capacitor according to Comparative Example 22 was obtained in the same manner as in Comparative Example 4, except that 0.1059 mmol (35.29 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Comparative Example 22, (A+C) / B was 2.41.

[0154] [Comparative Example 23] An electrolytic capacitor according to Comparative Example 23 was obtained in the same manner as in Comparative Example 5, except that 0.1059 mmol (35.29 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Comparative Example 23, (A+C) / B was 2.27.

[0155] [Comparative Example 24] An electrolytic capacitor according to Comparative Example 24 was obtained in the same manner as in Comparative Example 13, except that 0.1059 mmol (35.29 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Comparative Example 24, (A+C) / B was 1.99.

[0156] [Comparative Example 25] An electrolytic capacitor according to Comparative Example 25 was obtained in the same manner as in Comparative Example 21, except that 0.1059 mmol (35.29 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Comparative Example 25, (A+C) / B was 1.57.

[0157] [Comparative Example 26] An electrolytic capacitor according to Comparative Example 26 was obtained in the same manner as in Comparative Example 6, except that 0.1059 mmol (35.29 mol per kg of PEDOT / PSS) of ammonia was used as the first cationic component to obtain the first cationic component-containing polymer dispersion. In the electrolytic capacitor according to Comparative Example 26, (A+C) / B was 1.02.

[0158] [Comparative Example 27] An electrolytic capacitor according to Comparative Example 27 was obtained in the same manner as in Comparative Example 22, except that the electrolyte solution (liquid component) contained only phthalic acid (FT) as the anion component in the amount shown in Table 1C below. Specifically, the electrolyte solution (liquid component) contained 40.13 mol of phthalic acid (FT) per kg of PEDOT / PSS. In addition, the A / B ratio for the electrolytic capacitor according to Comparative Example 27 was 0.88.

[0159] [Comparative Example 28] An electrolytic capacitor according to Comparative Example 28 was obtained in the same manner as in Example 13, except that phthalic acid (FT) and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 24.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 26.43 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 28, (A + C) / B was 1.71.

[0160] [Comparative Example 29] An electrolytic capacitor according to Comparative Example 29 was obtained in the same manner as in Example 13, except that phthalic acid (FT) and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 24.94 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 24.94 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 29, (A+C) / B was 1.59.

[0161] [Comparative Example 30] An electrolytic capacitor according to Comparative Example 30 was obtained in the same manner as in Example 13, except that phthalic acid (FT) and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 26.98 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 21.58 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 30, (A + C) / B was 1.35.

[0162] Comparative Example 31 An electrolytic capacitor according to Comparative Example 31 was obtained in the same manner as in Example 15, except that phthalic acid (FT) and 1,2,3,4-tetramethylimidazolinium (TMI) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 21.78 mol per kg of PEDOT / PSS, and 1,2,3,4-tetramethylimidazolinium (TMI) was added in an amount of 23.96 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 31, (A+C) / B was 1.78.

[0163] [Comparative Example 32] An electrolytic capacitor according to Comparative Example 32 was obtained in the same manner as in Example 15, except that phthalic acid (FT) and 1,2,3,4-tetramethylimidazolinium (TMI) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 22.73 mol per kg of PEDOT / PSS, and 1,2,3,4-tetramethylimidazolinium (TMI) was added in an amount of 22.73 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 32, (A+C) / B was 1.65.

[0164] [Comparative Example 33] An electrolytic capacitor according to Comparative Example 33 was obtained in the same manner as in Example 15, except that phthalic acid (FT) and 1,2,3,4-tetramethylimidazolinium (TMI) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 24.88 mol per kg of PEDOT / PSS, and 1,2,3,4-tetramethylimidazolinium (TMI) was added in an amount of 19.91 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 33, (A+C) / B was 1.39.

[0165] [Comparative Example 34] An electrolytic capacitor according to Comparative Example 34 was obtained in the same manner as in Example 17, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.03 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 29.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 34, (A + C) / B was 1.65.

[0166] [Comparative Example 35] An electrolytic capacitor according to Comparative Example 35 was obtained in the same manner as in Example 17, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 27.86 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 27.86 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 35, (A + C) / B was 1.53.

[0167] [Comparative Example 36] An electrolytic capacitor according to Comparative Example 36 was obtained in the same manner as in Example 17, except that phthalic acid (FT) and dimethylethylamine (DEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 29.68 mol per kg of PEDOT / PSS, and dimethylethylamine (DEA) was added in an amount of 23.74 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 36, (A + C) / B was 1.30.

[0168] [Comparative Example 37] An electrolytic capacitor according to Comparative Example 37 was obtained in the same manner as in Example 20, except that phthalic acid (FT) and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 24.03 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 26.44 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 37, (A + C) / B was 1.71.

[0169] [Comparative Example 38] An electrolytic capacitor according to Comparative Example 38 was obtained in the same manner as in Example 20, except that phthalic acid (FT) and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 24.94 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 24.94 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 38, (A + C) / B was 1.59.

[0170] [Comparative Example 39] An electrolytic capacitor according to Comparative Example 39 was obtained in the same manner as in Example 20, except that phthalic acid (FT) and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, phthalic acid (FT) was added in an amount of 26.98 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 21.59 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 39, (A + C) / B was 1.35.

[0171] [Comparative Example 40] An electrolytic capacitor according to Comparative Example 40 was obtained in the same manner as in Example 22, except that azelaic acid and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 22.26 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 24.48 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 40, (A + C) / B was 1.76.

[0172] [Comparative Example 41] An electrolytic capacitor according to Comparative Example 41 was obtained in the same manner as in Example 22, except that azelaic acid and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 23.04 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 23.04 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 41, (A + C) / B was 1.64.

[0173] [Comparative Example 42] An electrolytic capacitor according to Comparative Example 42 was obtained in the same manner as in Example 22, except that azelaic acid and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 24.77 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 19.81 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 42, (A + C) / B was 1.39.

[0174] [Comparative Example 43] An electrolytic capacitor according to Comparative Example 43 was obtained in the same manner as in Example 22, except that azelaic acid and triethylamine (TEA) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 27.92 mol per kg of PEDOT / PSS, and triethylamine (TEA) was added in an amount of 13.96 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 43, (A + C) / B was 1.03.

[0175] [Comparative Example 44] An electrolytic capacitor according to Comparative Example 44 was obtained in the same manner as in Example 24, except that azelaic acid and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 22.26 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 24.48 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 44, (A + C) / B was 1.76.

[0176] [Comparative Example 45] An electrolytic capacitor according to Comparative Example 45 was obtained in the same manner as in Example 24, except that azelaic acid and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 23.04 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 23.04 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 45, (A + C) / B was 1.64.

[0177] [Comparative Example 46] An electrolytic capacitor according to Comparative Example 46 was obtained in the same manner as in Example 24, except that azelaic acid and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 24.77 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 19.81 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 46, (A + C) / B was 1.39.

[0178] [Comparative Example 47] An electrolytic capacitor according to Comparative Example 47 was obtained in the same manner as in Example 24, except that azelaic acid and methylmorpholine (MHP) were added to the mixed solvent in the amounts shown in Table 1C below to prepare an electrolyte solution (liquid component). Specifically, azelaic acid was added in an amount of 27.92 mol per kg of PEDOT / PSS, and methylmorpholine (MHP) was added in an amount of 13.96 mol per kg of PEDOT / PSS. In addition, in the electrolytic capacitor according to Comparative Example 47, (A + C) / B was 1.03.

[0179] The compositions of the conductive polymer layer and the electrolyte solution, as well as (A+C) / B, for Examples 1 to 24 are shown in Table 1A below. The compositions of the conductive polymer layer and the electrolyte solution, as well as (A+C) / B, for Comparative Examples 1 to 24 are also shown in Table 1B below. Furthermore, the compositions of the conductive polymer layer and the electrolyte solution, as well as (A+C) / B, for Comparative Examples 25 to 47 are also shown in Table 1C below.

[0180]

[0181]

[0182]

[0183] <Evaluation> <Initial Capacitance, Equivalent Series Resistance, and Leakage Current Measurements> For each electrolytic capacitor (Examples 1 to 24 and Comparative Examples 1 to 47), the initial capacitance (unit: μF) and the initial equivalent series resistance (unit: mΩ) at a frequency of 120 kHz were measured using an LCR meter. The measurement temperature was 20°C. Measurements of the initial capacitance and initial equivalent series resistance were taken for 20 samples each, and the arithmetic mean of the measurements was calculated. These arithmetic mean values ​​were used as the initial capacitance and initial equivalent series resistance values ​​for each electrolytic capacitor. A 1 kΩ resistor was connected in series to each electrolytic capacitor, and the initial leakage current (unit: μA) was measured after applying a rated voltage of 25 V from a DC power supply for 120 seconds. For the initial leakage current, the arithmetic mean of the measurements of the 20 samples was used as the initial leakage current value for each electrolytic capacitor. The initial capacitance, initial equivalent series resistance, and initial leakage current for the electrolytic capacitors of Examples 1 to 24 are shown in Table 2A below. The initial capacitance, initial equivalent series resistance, and initial leakage current for the electrolytic capacitors of Comparative Examples 1 to 24 are shown in Table 2B below. The initial capacitance, initial equivalent series resistance, and initial leakage current for the electrolytic capacitors of Comparative Examples 25 to 47 are shown in Table 2C below. <<Measurement of Capacitance, Equivalent Series Resistance, and Leakage Current After Reflow Treatment>> Assuming exposure to high temperatures during the reflow (RF) process, the electrolytic capacitors of each example were heated at 200°C to 260°C for 70 seconds. Then, the capacitance, equivalent series resistance, and leakage current for the electrolytic capacitors of each example after the heat treatment were measured. That is, the capacitance, equivalent series resistance, and leakage current after the reflow treatment were measured. These measurements were performed in the same manner as described above.The capacitance after reflow treatment, the equivalent series resistance after reflow treatment, and the leakage current after reflow treatment for the electrolytic capacitors of Examples 1 to 24 are shown in Table 2A below. The capacitance after reflow treatment, the equivalent series resistance after reflow treatment, and the leakage current after reflow treatment for the electrolytic capacitors of Comparative Examples 1 to 24 are shown in Table 2B below. The capacitance after reflow treatment, the equivalent series resistance after reflow treatment, and the leakage current after reflow treatment for the electrolytic capacitors of Comparative Examples 25 to 47 are shown in Table 2C below.

[0184]

[0185]

[0186]

[0187] Table 2A shows that the electrolytic capacitors according to Examples 1 to 24 have high capacitance, low leakage current, and low equivalent series resistance even after reflow treatment. On the other hand, Tables 2B and 2C show that the electrolytic capacitors according to Comparative Examples 1 to 47 exhibit at least one of a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance after reflow treatment.

[0188] The electrolytic capacitor according to the present disclosure can be used in applications that require simultaneously suppressing a decrease in capacitance, an increase in leakage current, and an increase in equivalent series resistance, even after exposure to thermal stress such as that caused by reflow soldering.

[0189] 10: Capacitor element, 11: Anode foil, 12: Cathode foil, 13: Separator, 14: Winding tape, 100: Electrolytic capacitor, 101: Bottomed case, 102: Sealing member, 103: Seat plate, 104A, 104B: Lead wires, 105A, 105B: Lead tabs

Claims

1. An electrolytic capacitor comprising a capacitor element and a liquid component, wherein the capacitor element comprises: an anode foil having a dielectric layer; a cathode foil disposed so as to face the dielectric layer; a separator interposed between the anode foil and the cathode foil; and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, wherein the conductive polymer layer comprises a conductive polymer, and a solid-liquid electrolyte comprising the conductive polymer layer and the liquid component comprises a first cationic component, a second cationic component, and an anionic component, wherein the conductive polymer layer comprises the first cationic component, and the liquid component comprises the second cationic component and the anionic component, and wherein, in the solid-liquid electrolyte, a ratio of the number of moles of the first cationic component to the mass of the conductive polymer is A (mol / kg), a ratio of the number of moles of the anionic component to the mass of the conductive polymer is B (mol / kg), and a ratio of the number of moles of the second cationic component to the mass of the conductive polymer is C (mol / kg), The electrolytic capacitor, wherein the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B≦1.

01.

2. An electrolytic capacitor comprising a capacitor element and a liquid component, wherein the capacitor element comprises: an anode foil having a dielectric layer; a cathode foil arranged so as to face the dielectric layer; a separator interposed between the anode foil and the cathode foil; and a conductive polymer layer interposed between the anode foil and the cathode foil and in contact with the separator, wherein the conductive polymer layer comprises a conductive polymer, and a solid-liquid electrolyte comprising the conductive polymer layer and the liquid component comprises a first cation component and an anion component, wherein the conductive polymer layer comprises the first cation component, and the liquid component comprises the anion component, wherein, in the solid-liquid electrolyte, the ratio of the number of moles of the first cation component to the mass of the conductive polymer is A (mol / kg) and the ratio of the number of moles of the anion component to the mass of the conductive polymer is B (mol / kg), the ratio A and the ratio B satisfy the relationship 0.20≦A / B≦1.

01.

3. The electrolytic capacitor according to claim 1, wherein the ratio A, the ratio B, and the ratio C satisfy the relationship 0.20≦(A+C) / B<1.

4. The electrolytic capacitor according to claim 2, wherein the ratio A and the ratio B satisfy the relationship 0.20≦A / B<1.

5. The electrolytic capacitor according to claim 1 or 3, wherein the ratio A is in the range of 1 mol / kg or more and 30 mol / kg or less, the ratio B is in the range of 25 mol / kg or more and 45 mol / kg or less, and the ratio C is in the range of 1 mol / kg or more and 25 mol / kg or less.

6. The electrolytic capacitor according to claim 1 or 3, wherein the valence of the first cationic component and the second cationic component is both 1.

7. The electrolytic capacitor according to any one of claims 1 to 4, wherein the pKa of the first cationic component is 10 or less.

8. The electrolytic capacitor according to claim 1 or 3, wherein the pKa of the second cationic component is 11 or less.

9. The electrolytic capacitor according to any one of claims 1 to 4, wherein the anion component is at least one selected from the group consisting of aromatic carboxylic acids, aliphatic carboxylic acids, and salts thereof.

10. The electrolytic capacitor according to claim 9, wherein the aromatic carboxylic acid is at least one selected from the group consisting of o-phthalic acid, salicylic acid, and benzoic acid.

11. The electrolytic capacitor according to claim 9, wherein the aliphatic carboxylic acid is at least one selected from the group consisting of adipic acid, azelaic acid, and sebacic acid.

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