JP2010098104A - Conductive polymer electrolytic capacitor subjected to chemical repair using ionic liquid diluted with water, and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that large amounts of additives are required for revealing the effect of increase in breakdown voltage but make it difficult to achieve both a high breakdown voltage and a low ESR with respect to addition of materials into an electrolyte in a conductive polymer capacitor. <P>SOLUTION: The conductive polymer aluminum electrolytic capacitor having both a high breakdown voltage and a low ESR can be obtained by performing a chemical repair by using a solution where the percent concentration, by weight, of ionic liquid is 0.01 to 5 wt.%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a conductive polymer electrolytic capacitor subjected to restoration conversion using an ionic liquid diluted with water, and a method for producing a conductive polymer electrolytic capacitor.

  Conductive polymer electrolytic capacitors are generally electrolytes comprising a valve metal such as aluminum, tantalum, or niobium as an anode metal, an oxide film formed on the surface thereof as a dielectric, and a conductive polymer formed on the dielectric. The cathode is formed with the layers in between.

  In general, polypyrrole or polythiophene derivatives are used as the conductive polymer. These conductive polymers have a low ability to repair dielectric oxide films, and capacitors using conductive polymers as electrolytes have a lower breakdown voltage than capacitors using conventional electrolytes. As an attempt to improve the withstand voltage, the addition of an inorganic salt into the electrolyte (Patent Document 1) and the addition of an ionic liquid (Patent Document 2) have been performed. In the former attempt, an inorganic hydroxide that undergoes endothermic reaction is added to the electrolyte, thereby slowing the reaction that insulates part of the conductive polymer and improving the withstand voltage. The latter attempt Aims to improve the withstand voltage by imparting an anodic oxidation ability of an ionic liquid to a conductive polymer having a low repair ability.

However, in the former method, since an inorganic salt material is added to the electrolyte, a large amount of additive is required to develop the effect of improving the pressure resistance, resulting in an increase in equivalent series resistance (ESR). Although a high breakdown voltage is realized, there is a problem that it is difficult to achieve a low ESR. In addition, since the additive is liquid in the latter method, the amount of addition necessary for the development of the pressure-resistant effect may be less than that of the inorganic salt, but the amount of the ionic liquid of about 5 to 10 wt% of the conductive polymer is It was necessary and this was a factor preventing the low ESR.
Japanese Patent No. 3551020 International Publication WO2005 / 012599 Pamphlet

  The present invention has been made to solve the above-described problems, and the object of the present invention is to provide a capacitor that achieves both high breakdown voltage and low impedance with a smaller amount of ionic liquid than the conventional method, and a method for manufacturing the same. Is to provide.

  As a result of intensive investigations in view of the above, the inventors of the present invention achieved a pressure resistance characteristic without damaging the ESR characteristic by performing a repair conversion using a solution obtained by diluting a hydrophilic ionic liquid with a certain amount of water. The present inventors have found that an excellent conductive polymer electrolytic capacitor can be obtained, and have made the present invention.

  That is, the present invention includes a step of performing restoration conversion using a solution containing at least an ionic liquid and water and having a weight% concentration of the ionic liquid in the range of 0.01 wt% to 5 wt% in the manufacturing process. The present invention relates to a conductive polymer electrolytic capacitor characterized by the following.

  Capacitors obtained by repairing with an ionic liquid solution diluted with a certain amount of water can form an oxide film with few defects, and can achieve both low impedance and high breakdown voltage.

<Ionic liquid>
First, the ionic liquid used in the present invention will be described. An ionic liquid is also called a room temperature molten salt, and refers to a liquid that is liquid at room temperature despite being composed only of ions, and is composed of a combination of a cation such as imidazolium and an appropriate anion.

  It has already been reported that ionic liquids have anodizing ability for valve metals such as aluminum, tantalum, niobium, etc. For example, high withstand voltage conductivity utilizing the ability to repair defects in aluminum oxide film Polymer capacitors have been made. The anodic oxidation ability here refers to the ability to form an oxide film on the valve metal and the ability to repair defects in the previously formed oxide film.

  Valve metal is also called valve metal. The metal surface is uniformly covered with the surface of the metal oxide film by anodic oxidation and exhibits excellent corrosion resistance. The oxide film flows in one direction and reverse direction. Means a so-called rectifying action (valve action) that is very difficult to flow. Aluminum, tantalum, niobium, titanium, hafnium, zinc, tungsten, bismuth, antimony, and the like are known as metals that are covered with an oxide film by anodic oxidation and exhibit a rectifying action. Among these, aluminum, tantalum are among these. Niobium and the like are used for conductive polymer electrolytic capacitors.

  Next, the anion component of the ionic liquid used in the present invention will be described. For the purpose of the present invention, an ionic liquid having an anionic component of an ionic liquid having a carboxylate anion, a sulfonate anion, a hydroxy anion, an imide anion, a halogen anion, a boron anion, a phosphorus anion, etc. can be used. Ionic liquids having a carboxylate anion are particularly preferred for the purposes of the present invention.

  Carboxylate anion is formate anion or general formula (1);

で表されるアニオンを有するイオン性液体を用いることができる。前記式（１）で表されるアニオンを有するイオン性液体について説明する。前記式（１）で表されるアニオンは後述するカチオンと対になって常温で液体の塩、すなわちイオン性液体を形成する。前記式（１）において、Ｒ¹及びＲ²は、それぞれ独立に水素原子、保護又は無保護の水酸基、保護又は無保護のアミノ基、アルコキシ基、ニトロ基、シアノ基、カルボキシル基、ハロゲン原子、直鎖または分岐もしくは環を形成していてもよく置換基を有していてもよいＣ₁〜Ｃ₂₀のアルキル基，直鎖または分岐もしくは環を形成していてもよく置換基を有していてもよいＣ₂〜Ｃ₂₀のアルケニル基，直鎖または分岐もしくは環を形成していてもよく置換基を有していてもよいＣ₂〜Ｃ₂₀のアルキニル基，置換基を有していてもよいＣ₆〜Ｃ₂₀のアリール基，置換基を有していてもよいＣ₄〜Ｃ₂₀のヘテロアリール基，置換基を有していてもよいＣ₇〜Ｃ₂₀のアラルキル基，置換基を有していてもよいＣ₄〜Ｃ₂₀のヘテロアラルキル基を表し、互いに同じであっても異なっていてもよく、また一緒になって環を形成してもよい。

An ionic liquid having an anion represented by can be used. The ionic liquid having an anion represented by the formula (1) will be described. The anion represented by the formula (1) is paired with a cation described later to form a salt that is liquid at room temperature, that is, an ionic liquid. In the formula (1), R ¹ and R ² are each independently a hydrogen atom, a protected or unprotected hydroxyl group, a protected or unprotected amino group, an alkoxy group, a nitro group, a cyano group, a carboxyl group, a halogen atom, C ₁ -C ₂₀ alkyl group which may form a straight chain or branched or ring and may have a substituent, may have a substituent which may form a linear or branched or ring alkenyl group which may C ₂ -C _20, a linear or branched or alkynyl group optionally C ₂ -C ₂₀ optionally having also well substituent to form a ring, substituted C ₆ -C ₂₀ aryl group, C ₄ -C ₂₀ heteroaryl group optionally having substituent, C ₇ -C ₂₀ aralkyl group optionally having substituent, substituent Represents a C _{4 to} C ₂₀ heteroaralkyl group optionally having These may be the same as or different from each other, and together may form a ring.

  In the present invention, “may have a substituent” means that it may be substituted with another atom or substituent. The “substituent” is not particularly limited as long as it does not adversely affect the reaction. Specifically, the hydroxyl group, alkyl group, alkoxy group, alkylthio group, nitro group, amino group, cyano group, carboxyl group, A halogen atom etc. are mentioned.

As more specific examples of R ¹ and R ^2, the C ₁ -C ₂₀ alkyl group which may form a straight chain, a branched chain or a ring and may have a substituent is particularly limited. Although not intended, for example, methyl group, hydroxymethyl group, ethyl group, n-propyl group, isopropyl group, cyclopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group , A cyclopentyl group, an n-hexyl group, a cyclohexyl group, an n-octyl group, an n-decyl group, and the like, and those obtained by substituting an arbitrary number of hydrogen atoms of these alkyl groups with fluorine atoms. Can be mentioned. Examples of the alkenyl group which may form a C _{2 to} C ₂₀ straight chain or branched or ring and may have a substituent include, for example, vinyl group, propenyl group, styryl group, isopropenyl group, cyclopropenyl Group, butenyl group, cyclobutenyl group, cyclopentenyl group, hexenyl group, cyclohexenyl group and the like. Examples of the alkynyl group which may form a C _{2 to} C ₆ straight chain or branched or ring and may have a substituent include, for example, an ethynyl group, a propynyl group, a phenylethynyl group, a cyclopropylethynyl group, Examples include butynyl, pentynyl, cyclobutylethynyl group, and hexynyl group. Examples of the aryl group that may have a substituent include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a terphenyl group, and a 3,4,5-trifluorophenyl group. Examples of the heteroaryl group which may have a substituent include, for example, pyrrolinyl group, pyridyl group, quinolyl group, imidazolyl group, furyl group, indolyl group, thienyl group, oxazolyl group, thiazolyl group, 2-phenylthiazolyl group. , 2-anisyl thiazolyl group and the like. Examples of the aralkyl group which may have a substituent include benzyl, chlorobenzyl, bromobenzyl, salicyl, α-hydroxybenzyl, phenethyl, α-hydroxyphenethyl, naphthylmethyl, and anthracyl. Examples include senylmethyl group, 3,5-difluorobenzyl group, and trityl group. Examples of the heteroaralkyl group which may have a substituent include a pyridylmethyl group, a difluoropyridylmethyl group, a quinolylmethyl group, an indolylmethyl group, a furfuryl group, and a thienylmethyl group. In addition, when R ¹ or / and R ² has a hydroxyl group as a substituent, the hydroxyl group may be protected or unprotected, and when it is protected, the protecting group is not particularly limited. Examples of the method include various ethers, various esters, various sulfonate esters, and various carbonate esters.

From the viewpoint of anodic oxidation ability and availability, at least one of R ¹ and R ² is a hydrogen atom or a hydroxyl group, and the other is a methyl group, an ethyl group, a trifluoromethyl group, a phenyl group, a benzyl group, or a naphthyl group. A group or the like is preferable. When at least one of R ¹ and R ² is a hydroxyl group, it may be protected or unprotected, but generally unprotected is preferable because it exhibits a higher anodic oxidation ability. More specifically, at least one of R ¹ and R ² is a hydroxyl group and the other is a phenyl group, that is, mandelic acid or a derivative thereof is particularly preferable. Also preferred are those in which R ¹ and R ² together form a cyclohexyl group or a phenyl group.

  The ionic liquid that can be used is not limited to the carboxylate anion, and an ionic liquid having a sulfonate anion, a hydroxy anion, an imide anion, a halogen anion, a boron anion, and a phosphorus anion can be used.

  Specific examples of the sulfonate anion include benzene sulfonate anion, toluene sulfonate anion, alkyl naphthalene sulfonate anion, naphthalene sulfonate anion, anthraquinone sulfonate anion, and hydroxy sulfonate anion. is not.

  Examples of the imide anion include a bis (trifluoromethanesulfonyl) imide anion, a bis (pentafluoroethanesulfonyl) anion, a bis (naphthylfluorobutanesulfonyl) imide anion, and the like.

  Examples of the halogen anion include a fluorine anion, a bromine anion, and an iodine anion. Of course, it is not limited to these examples suitable for the present invention.

  Examples of the cyano anion include a cyano anion, a boron anion includes a tetrafluoroboron anion, and a phosphorus anion includes a hexafluorophosphorus anion, but the anion is not limited thereto.

  Next, the cation component of the ionic liquid will be described. Cationic components include ammonium and its derivatives, imidazolinium and its derivatives, pyridinium and its derivatives, pyrrolidinium and its derivatives, pyrrolinium and its derivatives, pyrazinium and its derivatives, pyrimidinium and its derivatives, triazonium and its derivatives, triazinium and its derivatives Derivatives, triazine and derivatives thereof, quinolinium and derivatives thereof, isoquinolinium and derivatives thereof, indolinium and derivatives thereof, quinoxalinium and derivatives thereof, piperazinium and derivatives thereof, oxazolinium and derivatives thereof, thiazolinium and derivatives thereof, morpholinium and derivatives thereof, Piperazine and its derivatives, but the resulting ionic liquid is relatively low Because they exhibit a viscosity, imidazolium derivatives are preferred, as the imidazolium derivatives diethyl imidazolium, ethyl butyl imidazolium, dimethyl imidazolium are preferred, particularly preferably ethyl methyl imidazolium, methyl butyl imidazolium.

  In addition, said ionic liquid may be used individually for the ionic liquid of this invention, and 2 or more types may be mixed and used for it in arbitrary ratios.

<Concentration of ionic liquid aqueous solution>
The concentration of the ionic liquid aqueous solution used for anodic oxidation in the present invention is preferably in the range of 0.01 wt% to 5 wt%, more preferably 0.01 wt% to 2 wt% from the viewpoint of achieving both high breakdown voltage and low ESR. A range of 0.02 wt% to 1 wt% is most preferable.

  In the region where the concentration of the ionic liquid is lower than 0.01 wt%, it is not possible to flow a sufficient amount of electricity to perform anodic oxidation, and an oxide film cannot be formed. On the other hand, in a region having a concentration higher than 5 wt%, although it varies depending on the type of ionic liquid, in general, it is often impossible to reduce the current even if restoration conversion is performed.

  As described above, the main point of the present invention is that anodic oxidation is preferably performed within the concentration range of the ionic liquid.

  That is, the process of anodizing in the aqueous ionic liquid solution of the present invention is a process that can form and repair an oxide film by the excellent anodic oxidation property of the ionic liquid. Since an electrolyte containing an ionic liquid can be formed, a conductive polymer capacitor having excellent characteristics can be produced.

  Next, additives that can be added to the ionic liquid aqueous solution in the present invention will be described. The ionic liquid aqueous solution used in the present invention includes a nitro compound, a phosphoric acid compound, a boric acid compound, a polyhydric alcohol as necessary in order to promote film formation at the time of restoration conversion and adhesion of the ionic liquid to the vicinity of the electrode. , Silicon compounds, ammonium salts, amine salts, quaternary ammonium salts, tertiary amines and organic acids, imidazolium salts and other additives can be added. Examples of nitro compounds include nitrophenol, nitroacetophenone, nitrobenzoic acid, nitrobenzyl alcohol, nitrocresol, nitrotoluene, nitroanisole and the like. Examples of phosphoric acid compounds include orthophosphoric acid, phosphorous acid, hypophosphorous acid, pyrophosphoric acid, polyphosphoric acid, methyl phosphate, ethyl phosphate, butyl phosphate, isopropyl phosphate, dibutyl phosphate, dioctyl phosphate, etc. Is mentioned. Examples of boric acid compounds include boric acid and its complex compounds. Examples of the polyhydric alcohols include erythritol, glycerin, threitol, ribitol, arabinitol, allitol, glucitol, mannitol, sorbitol, xylitol, iditol, galactitol, taritol, polyvinyl alcohol and the like. Examples of the silicon compound include colloidal silica, aluminosilicate, silicone compound, silane coupling agent and the like. Examples of ammonium salts include ammonium adipate, ammonium borate, ammonium phosphate, ammonium adipate, and ammonium maleate. Examples of the amine salt include triethylamine maleate, and examples of the quaternary ammonium salt include quaternary ammonium maleate and quaternary ammonium phthalate. Examples of tertiary amines and organic acids include combinations of tertiary amines such as triethylamine and diisopropylethylamine and adipic acid, phosphoric acid, boric acid, salicylic acid, malic acid, succinic acid, and the like. Examples of the imidazolium salt include 1,3-ethylmethylimidazolium-p-toluenesulfonate, 1,3-butylmethylimidazolium-p-toluenesulfonate, 1,3-ethylmethylimidazolium-p-tri Examples thereof include fluoromethylphenyl sulfonate and 1,3-butylmethylimidazolium-p-trifluoromethylphenyl sulfonate.

  By using these additives in combination with the ionic liquid aqueous solution of the present invention, anodization outside the range of 0.01 wt% to 5 wt%, which is a preferable range of the ionic liquid aqueous solution of the present invention, becomes possible. .

  For example, by adding 0.1 wt% phosphoric acid to an aqueous solution containing 0.01 wt% or less of ionic liquid, anodic oxidation and restoration conversion can be performed. However, although the capacitor produced by such a method has good ESR characteristics, the breakdown voltage characteristics deteriorate. A possible cause is that the concentration of the ionic liquid is dilute and an anodic oxide film having a sufficient thickness cannot be formed.

  On the other hand, by adding a quaternary ammonium salt or a tertiary amine to an aqueous solution containing 5 wt% or more of an ionic liquid, anodization and restoration conversion can be performed. However, the capacitor element manufactured by such a method has good breakdown voltage characteristics but deteriorates ESR characteristics. The cause is that when a high concentration solution is used, the ionic liquid remains in the vicinity of the electrode, the conductive polymer concentration in the vicinity of the electrode decreases during the formation of the electrolyte, and the electron conductivity decreases. I think.

<Repair formation>
Next, restoration conversion will be described.
Usually, when manufacturing a conductive polymer electrolytic capacitor, a voltage is applied to an etched valve metal foil in a chemical conversion solution to form a dielectric oxide film on the surface of the metal foil. And used as an anode foil. Moreover, although an etching foil is used for the cathode foil, a dielectric oxide film of several volts may be formed. And after forming the capacitor element by winding the anode foil and the cathode foil thus formed through a separator, the cut surface of the electrode foil and the oxide film damaged in the capacitor element creation process are repaired. . That is, by applying a voltage to the capacitor element in the chemical liquid, an oxide film is formed on the damaged portion to repair the capacitor element. Repair chemical conversion refers to repairing a damaged portion by applying a voltage to a capacitor element in a chemical conversion liquid to form an oxide film.

  The restoration chemical conversion solution is generally carried out in a neutral aqueous solution such as borate, phosphate or adipate. It is not always necessary to use only a mixture of an ionic liquid and water, and a solvent may be contained as an optional component. The solvent used may be a known solvent and is not particularly limited. For example, methanol, ethanol, butanol, 2-propanol, acetone, diethyl ether, ethyl acetate, THF, DMF, acetonitrile, DMSO, dimethyl carbonate, ethylene Examples include carbonate, propylene carbonate, hexane, toluene, chloroform, and the like, which may be selected according to the purpose. However, it is necessary to consider the electrochemical stability of the solvent and the incorporation of impurities derived from the solvent.

  Moreover, although the temperature of a solution does not have a problem even if it is room temperature, when performing a chemical conversion treatment for a short time, it is preferable to work at the temperature of about 50 to 80 degreeC.

  In a normal electrolytic solution type electrolytic capacitor, the electrolytic solution itself has an effect of forming a cut surface of the electrode foil or a damaged portion of the oxide film, and therefore, it is not necessary to separately perform repair formation. However, since the conductive polymer electrolyte does not have the effect of performing the repair conversion, the repair conversion process is very important in manufacturing the conductive polymer electrolytic capacitor. In addition, since the withstand voltage characteristic of the conductive polymer electrolytic capacitor is defined by the withstand voltage of the thinnest part of the oxide film of the electrode foil, it is important how much oxide film is formed at the time of restoration formation. .

  As described above, the present inventors formed an oxide film by using a solution containing an ionic liquid having an anodic oxidation capability for restoration conversion.

<Method for producing conductive polymer capacitor>
Next, a method for producing a conductive polymer electrolytic capacitor in the present invention will be described.

  By combining a dielectric made of an oxide film formed by the anodic oxidation method with the valve metal, an anode made of the valve metal and the dielectric oxide film can be formed and used as an anode of a capacitor.

  First, a wound type conductive polymer aluminum electrolytic capacitor will be described. A capacitor constructed by winding the anode foil and the cathode foil with a separator interposed therebetween, wherein an electrolyte made of a conductive polymer is provided between the anode foil and the cathode foil, and the element For example, after being stored in a bottomed cylindrical aluminum case, the opening of the aluminum case can be sealed with a sealing agent to form a wound conductive polymer aluminum electrolytic capacitor.

  As the cathode of the conductive polymer capacitor of the present invention, for example, carbon paste and silver paste can be formed by a conventionally known method. The anode and cathode are each connected to a terminal. In this way, a conductive polymer aluminum electrolytic capacitor having at least an anode, an electrolyte, and a cathode can be formed.

  Next, a chip type tantalum capacitor will be described. In the chip type tantalum capacitor, an oxide film / conductive polymer / carbon layer / silver paste layer formed by the above method is sequentially formed on a sintered body produced by molding and firing tantalum powder. A tantalum wire is embedded in the sintered body or welded to the surface.

  First, powder metal tantalum is sintered into a rectangular parallelepiped shape to obtain a microporous anode body, and then a surface of the anode body (including the surface of micropores) is coated with a tantalum oxide film as a dielectric. It forms by said anodic oxidation method. Next, a conductive polymer layer such as pyrrole or thiophene as a solid electrolyte layer is formed on the tantalum oxide film, and a cathode conductor layer is further formed thereon. The cathode conductor layer is composed of, for example, a graphite layer and a silver paste layer stacked in this order.

  The conductive polymer used in the present invention is not particularly limited, and examples thereof include polythiophene or a derivative thereof, polypyrrole or a derivative thereof, polyaniline or a derivative thereof. 3,4-ethylenedioxythiophene or pyrrole is preferred because of its high conductivity during polymer formation and stability in the air. From the viewpoint of the conductivity and heat resistance of the resulting conductive polymer, 3,4 -Ethylenedioxythiophene is particularly preferred.

  Next, a method for producing a conductive polymer capacitor electrolyte by chemical polymerization in the present invention will be described. The conductive polymer capacitor here means a capacitor using a conductive polymer as an electrolyte. The chemical polymerization method is a method of polymerizing and synthesizing a conductive polymer monomer such as pyrrole in the presence of an appropriate oxidizing agent. Examples of the oxidizing agent include ferric paratoluenesulfonate, ferric naphthalenesulfonate, ferric n-butylnaphthalenesulfonate, ferric triisopropylnaphthalenesulfonate, persulfate, hydrogen peroxide, diazonium salt , Halogens and halides, or transition metal salts such as iron, copper, and manganese can be used. The conductive polymer synthesized by chemical polymerization can obtain a polymer having conductivity in a one-step reaction by incorporating an anion of an oxidant into the polymer as a dopant in the polymerization process. It is preferable to use ferric paratoluenesulfonate containing paratoluenesulfonate ions having high mobility as an oxidizing agent.

  The polymerization conditions may be known polymerization conditions, and the temperature range is from -100 ° C to 200 ° C, particularly preferably from -30 ° C to 150 ° C. The polymerization time is 1 minute to 120 hours, particularly preferably 1 minute to 1440 minutes. The polymerization may be repeated a plurality of times.

  In the conductive polymer electrolytic capacitor of the present invention using the oxide film formed by the above method, the constituent elements of the capacitor not particularly mentioned are not particularly limited, and conventionally known ones should be appropriately applied. Can do.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited at all by these Examples, In the range which does not change the summary, it can change suitably.

<Ionic liquid and salt>
First, a method for synthesizing or obtaining ionic liquids and salts used as examples will be described.

1-butyl-3-methylimidazolium mandelate ([BMIm] [MA])

  1-butyl-3-methylimidazolium hydrogen carbonate 50% aqueous solution (5000 mg, 12.48 mmol) was added, and the mixture was cooled to 0 ° C. Thereafter, an aqueous solution of mandelic acid (1899 mg, 12.48 mmol) was slowly added dropwise and stirred at room temperature for 1 hour. The reaction solution was concentrated as it was, the solvent was distilled off under reduced pressure, dichloromethane was added to the resulting residue, and the organic layer was dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 3622.3 mg of the target compound as a light brown oil. (Yield 100%)

¹ H NMR (CDCl ₃ , 300 MHz) δ 0.93 (t, 3H), 1.29-1.34 (m, 2H), 1.74-1.79 (m, 2H), 3.84 (s, 3H), 4.10 (t, 2H), 4.92 (s, 1H), 7.04 (s, 1H), 7.14-7.26 (m, 1H), 7.23-7.26 (M, 3H), 7.54 (d, 2H), 10.74 (s, 1H)

1-ethyl-3-methylimidazolium lactate (hereinafter abbreviated as [BMIm] [LA])

アルドリッチより購入した。

Purchased from Aldrich.

1-butyl-3-methylimidazolium acetate (hereinafter abbreviated as [BmIm] [AcO])

アルドリッチより購入した。

Purchased from Aldrich.

1-butyl-3-methylimidazolium trifluoroacetate (hereinafter abbreviated as [BmIm] [TFA])

メルクより購入した。

Purchased from Merck.

1-butyl-3-methylimidazolium benzoate (hereinafter abbreviated as [BmIm] [BA])

  1-butyl-3-methylimidazolium hydrogen carbonate 50% aqueous solution (4000 mg, 9.98 mmol) was added, and the mixture was cooled to 0 ° C. Thereafter, an aqueous solution of benzoic acid (1219 mg, 9.98 mmol) was slowly added dropwise and stirred at room temperature for 1 hour. The reaction solution was concentrated as it was, the solvent was distilled off under reduced pressure, dichloromethane was added to the resulting residue, and the organic layer was dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 1824.2 mg of the target compound as a light brown oil. (Yield 70%)

¹ H NMR (CDCl ₃ , 300 MHz) δ 0.90 (t, 3H), 1.28-1.35 (m, 2H), 1.76-1.87 (m, 2H), 4.06 (s, 3H), 4.27 (t, 2H), 7.14 (d, 2H), 7.27-7.34 (m, 3H), 8.07-8.10 (m, 2H), 11.39 (S, 1H)

1-butyl-3-methylimidazolium caprylate (hereinafter abbreviated as [BmIm] [CA])

  1-butyl-3-methylimidazolium hydrogen carbonate 50% aqueous solution (5.00 g, 12.48 mmol) was added, and the mixture was cooled to 0 ° C. Thereafter, an aqueous solution of caprylic acid (1.80 g, 12.48 mmol) was slowly added dropwise and stirred at room temperature for 1 hour. The reaction solution was concentrated as it was, the solvent was distilled off under reduced pressure, dichloromethane was added to the resulting residue, and the organic layer was dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 2.20 g of the target compound as a yellow oil. (Yield 62%)

¹ H NMR (CDCl ₃ , 300 MHz) δ 0.83-0.92 (m, 7H), 1.21-1.29 (m, 11H), 1.38 (m, 2H), 1.73-1. 78 (m, 2H), 3.85 (s, 3H), 4.17 (t, 2H), 7.72 (s, 1H), 7.79 (s, 1H), 9.39 (s, 1H) )

1-butyl-3-methylimidazolium phenylacetate (hereinafter abbreviated as [BmIm] [PA])

  Amberlite IRA400 (OH) (140 mL) was added to the chromatographic column tube, 1N NaOH aqueous solution (2.5 L) was poured to activate the Amberlite IRA400 (OH), and then purified water (1.5 L) until the filtrate became neutral. ). After adding pure water (50 mL) to 1-butyl-3-methylimidazolium chloride (5.0 g, 28.63 mmol) and dissolving it, this was passed through the previously activated Amberlite IRA400 (OH) to give 1-butyl An aqueous solution of -3-methylimidazolium hydroxide was obtained. After adding pure water (200 mL) and THF (100 mL) to phenylacetic acid (3.9 g, 28.63 mmol) to make a homogeneous solution, 1-butyl-3-methylimidazolium hydroxide aqueous solution was slowly added dropwise thereto. Stir at 0 ° C. for 12 hours. The reaction solution was concentrated as it was, acetonitrile (90 mL) and methanol (10 mL) were added to the obtained residue, and the mixture was stirred at 0 ° C. for 30 min. The filtrate was concentrated and heated under reduced pressure to obtain 8.0 g of the target compound as a pale yellow oil. (Yield 100%)

¹ H NMR (DMSO-d ⁶ , 300 MHz) δ 0.89 (t, 3H), 1.21-1.28 (m, 2H), 1.70-1.77 (m, 2H), 3.23 ( s, 2H), 3.83 (s, 3H), 4.15 (t, 2H), 7.09-7.19 (m, 5H), 7.70 (s, 1H), 7.77 (s) 1H), 9.29 (s, 1H)

1-ethyl-3-methylimidazolium tosylate (hereinafter abbreviated as [EmIm] [TsO])

リン酸アンモニウム（[ＮＨ ₄ Ｈ ₂ ＰＯ ₄ ]） アルドリッチより購入した。

Ammonium phosphate ([NH ₄ H ₂ PO ₄ ]) was purchased from Aldrich.

<Production of wound capacitor>
Anode foil (U-157 50.2 Vfs made by KDK sales company or U-157 105 Vfs made by KDK sales company) and cathode foil (foil withstand voltage of 0 V; U-157 0Vfs made by KDK sales company) having an oxide film layer formed on the surface ) Is connected to the electrode drawing means, and both electrode foils are wound through a paper separator (FBAV3540, manufactured by Nippon Kogyo Paper Industries Co., Ltd.) to form a capacitor element (also called a winding element) having an element shape of 5φ × 2.5L. ) Was formed.

<Repair conversion treatment>
The wound element produced above is immersed in a 100 cc beaker containing various repairing chemical solutions, and the voltage is increased to 0.95 times the foil withstand voltage of the anode foil at a voltage increase rate of 100 mV / sec. Restoration conversion was carried out for a minute. Thereafter, drying was performed at 100 ° C. for 30 minutes in an air atmosphere. In addition, Hokuto Denko's potentiogalvanostat HA-3001A and function generator HB-104 were used for the apparatus.

<Formation of conductive polymer aluminum electrolytic capacitor>
In a predetermined container, EDOT (manufactured by Starck Vitec) and 50% ethanol solution of para-toluenesulfonic acid ferric acid were put in a molar ratio of 1: 2, and stirred and mixed for 10 seconds. Subsequently, the capacitor element (the wound element subjected to the repair conversion treatment) is immersed in the above mixed solution for 1 minute, and then heated at 150 ° C. for 30 minutes to generate a polymerization reaction of PEDOT in the capacitor element, so that the solid electrolyte layer Formed.

  Thereafter, aging was performed at a voltage 1.1 times the rated voltage at 100 ° C. for 60 minutes to form a conductive polymer aluminum electrolytic capacitor. The rated voltage of this capacitor is 25 WV (50.2 Vfs) and 35 WV (105 Vfs).

<Measurement of current value at the end of restoration formation>
The current and voltage at the time of the restoration formation were measured using a Takoroger made by Graphtec, and the current value at the end of the restoration formation was measured.

<Initial capacity measurement>
The initial capacity was measured immediately after aging using an Agilent LCR meter, model number “E4980A”. The measurement conditions were DC Potential: 0 V, AC Amplitude: 100 mV, and frequency: 120 Hz.

<Volume expression rate>
(Volume in liquid / initial capacity) × 100 was defined as “capacity expression rate (%)”, and the variation in liquid capacity of the winding elements used was normalized. The submerged volume is a value measured immediately after the repair formation.

<ESR measurement>
ESR was measured immediately after aging using an Agilent LCR meter, model number “E4980A”. The measurement conditions were DC Potential: 0 V, AC Amplitude: 100 mV, and frequency: 100 kHz.

<Measurement of breakdown pressure>
The breakdown voltage was measured by using a model number “TR6143” manufactured by Advantest Corporation and increasing the voltage at a rate of 20 mV / sec. The withstand voltage value was defined as the voltage at which a current of 100 mA flowed.

Example 1
Using a 50.2 Vfs anode foil, a capacitor element of 5φ × 2.5 L was formed according to the above <Preparation of a wound capacitor>.

  Subsequently, 0.01 wt% of the [BMIm] [MA] solution was used as the repair conversion solution, and repair conversion was performed according to the above <Repair conversion treatment>. Thereafter, a capacitor was produced according to <Formation of conductive polymer aluminum electrolytic capacitor>. Various data measurement methods were as described above. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Example 2)
The experiment was performed under the same conditions as in Example 1 except that a 2 wt% [BMIm] [MA] solution was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Example 3)
The experiment was performed under the same conditions as in Example 1 except that a 0.1 wt% [BMIm] [MA] solution was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

Example 4
The experiment was performed under the same conditions as in Example 1 except that 0.01 wt% [EMIm] [LA] solution was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Example 5)
The experiment was performed under the same conditions as in Example 1 except that 2 wt% [EMIm] [LA] was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Example 6)
The experiment was performed under the same conditions as in Example 1 except that 0.1 wt% [EMIm] [LA] was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Example 7)
The experiment was performed under the same conditions as in Example 1 except that a 5 wt% [BMIm] [MA] solution was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes.

(Examples 8 to 13)
The experiment was performed under the same conditions as in Example 1 except that the ionic liquid used was shown in Table 2. The data is shown in Table 2. The results in Table 2 are average values for all three electrodes.

(Example 14)
The experiment was carried out under the same conditions as in Example 1 except that a 0.1 wt% [BMIm] [MA] and a 0.1 wt% ammonium phosphate aqueous solution were mixed at a weight ratio of 1: 1 in the repair chemical solution. Was done. The data is shown in Table 3. All the results in Table 3 are average values of three electrodes.

(Example 15)
The experiment was performed under the same conditions as in Example 1 except that a solution obtained by mixing 0.1 wt% [EMIm] [LA] and 0.1 wt% ammonium phosphate aqueous solution at a weight ratio of 1: 1 was used as the restoration conversion solution. Was done. The data is shown in Table 3. All the results in Table 3 are average values of three electrodes.

(Example 16)
The experiment was performed under the same conditions as in Example 3 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 17)
The experiment was performed under the same conditions as in Example 6 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 18)
The experiment was performed under the same conditions as in Example 8 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 19)
The experiment was performed under the same conditions as in Example 9 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 20)
The experiment was performed under the same conditions as in Example 10 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 21)
The experiment was performed under the same conditions as in Example 11 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 22)
The experiment was performed under the same conditions as in Example 12 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 23)
The experiment was performed under the same conditions as in Example 13 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 24)
The experiment was performed under the same conditions as in Example 14 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Example 25)
The experiment was performed under the same conditions as in Example 15 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

(Comparative Example 1)
The experiment was performed under the same conditions as in Example 1 except that a 0.005 wt% [BMIm] [MA] solution was used as the repairing chemical solution. However, with the ionic liquid having such a concentration, a current necessary for anodization could not be passed, and as a result, restoration formation could not be performed.

(Comparative Example 2)
The experiment was performed under the same conditions as in Example 1 except that a 10 wt% [BMIm] [MA] solution was used as the repairing chemical solution. However, with such a concentration of ionic liquid, too much current flows, and the final current value at the time of restoration formation was 10 mA or more. From this, it was determined that such a concentration could not be repaired.

(Comparative Example 3)
The experiment was performed under the same conditions as in Example 1 except that a 0.1 wt% aqueous ammonium phosphate solution was used as the repairing chemical solution. The data is shown in Table 1. The results in Table 1 are average values of three electrodes. From this result, it was found that the device with a repaired conversion with an aqueous ammonium phosphate solution has a low breakdown voltage.

(Comparative Example 4)
The experiment was performed under the same conditions as in Example 1 except that 0.005 wt% of [BMIm] [MA] was added to a 0.1 wt% ammonium phosphate aqueous solution as the repairing chemical solution. Although restoration conversion was possible, the effect of improving pressure resistance was greater than that of the example.

(Comparative Example 5)
The experiment was performed under the same conditions as in Comparative Example 3 except that 105 Vfs was used for the anode foil. The data is shown in Table 4. All the results in Table 4 are average values of three electrodes.

Claims (8)

  High conductivity obtained by a manufacturing method including a step of repairing and forming a capacitor element using a solution containing at least an ionic liquid and water and having a weight% concentration of the ionic liquid in the range of 0.01 wt% to 5 wt%. Molecular electrolytic capacitor.   2. The anionic component of the ionic liquid is at least one selected from a carboxylate anion, a sulfonate anion, a hydroxy anion, an imide anion, a halogen anion, a boron anion, a cyano anion, and a phosphorus anion. The electroconductive polymer electrolytic capacitor as described. The carboxylate anion according to claim 2 is a formate anion or general formula (1);

(Wherein R ¹ and R ² are each independently a hydrogen atom, a protected or unprotected hydroxyl group, a protected or unprotected amino group, an alkoxy group, a nitro group, a cyano group, a carboxyl group, a halogen atom, a straight chain or branched or alkyl group optionally C ₁ -C ₂₀ optionally may have a substituent to form a ring, may have a straight-chain or branched or may substituents may form a ring C ₂ -C ₂₀ alkenyl group, straight chain, branched or ring may be formed and optionally substituted C ₂ -C ₂₀ alkynyl group, optionally substituted C _{6 to} C ₂₀ aryl group, optionally having C _{4 to} C ₂₀ heteroaryl group, optionally having C _{7 to} C ₂₀ aralkyl group and having substituent Represents a C _{4 to} C ₂₀ heteroaralkyl group which may be The conductive polymer electrolytic capacitor is characterized in that it is at least one selected from anions represented by the following formulas, which may be different from each other or may form a ring together.   The cation component of the ionic liquid is ammonium cation, imidazolium cation, pyridinium cation, pyrrolidinium cation, pyrrolium cation, pyrazinium cation, pyrimidinium cation, triazonium cation, triazinium cation, triazine cation, Group consisting of quinolinium cation, isoquinolinium cation, indolinium cation, quinoxalinium cation, piperazinium cation, oxazolinium cation, thiazolinium cation, morpholinium cation, piperazine cation and derivatives thereof The conductive polymer electrolytic capacitor according to claim 1, wherein the conductive polymer electrolytic capacitor is selected.   In addition to ionic liquid and water, it consists of nitro compounds, phosphoric acid compounds, boric acid compounds, polyhydric alcohols, silicon compounds, ammonium salts, amine salts, quaternary ammonium salts, tertiary amines and organic acids, imidazolium salts The conductive polymer electrolytic capacitor according to claim 1, wherein the repair conversion is performed using a solution containing at least one selected from the group.   The manufacturing method of the conductive polymer electrolytic capacitor in any one of Claims 1-5.   7. The method for producing a conductive polymer electrolytic capacitor according to claim 6, wherein the conductive polymer electrolytic capacitor is a wound aluminum electrolytic capacitor or a chip type tantalum electrolytic capacitor.   The method for producing a conductive polymer capacitor electrolyte according to claim 7, wherein the conductive polymer is formed by chemical polymerization.