JP4535435B2 - PI CONJUGATED COPOLYMER, PROCESS FOR PRODUCING THE SAME, AND CAPACITOR USING THE COPOLYMER - Google Patents

Description

  The present invention relates to a novel π-conjugated copolymer having high conductivity, a method for producing the same, and a capacitor using the copolymer. More specifically, it is a novel π suitable for use as various conductive materials such as electrodes, sensors, electronic display elements, photoelectric conversion elements, antistatic materials, optical materials, or various electronic parts, which require high workability in the electronics field. The present invention relates to a conjugated copolymer, a production method thereof, and a capacitor excellent in high-frequency characteristics using the copolymer.

  In general, conjugated double bond conductive polymers represented by polyaniline, polypyrrole, and polythiophene have been researched and developed in the past. Attention has been paid to the unique electronic, magnetic and optical properties. Typical methods for producing the conductive polymer include chemical oxidative polymerization and electrolytic polymerization.

  When electrolytic polymerization is used, a film-like polymer is deposited very densely on, for example, a platinum electrode in the electrolytic solution, and a polymer exhibiting excellent performance is obtained. However, it has a serious problem related to the production cost and is not suitable for mass production.

  In chemical oxidative polymerization, a conductive polymer can be easily obtained by mixing a polymerizable monomer and an appropriate oxidant. Therefore, research and development have been carried out focusing on the simple polymerization method industrially. In particular, development of a conductive polymer material having high electrical conductivity as a polymer material that replaces a metal-based material has been eagerly desired particularly for use as a solid electrolyte of a solid electrolytic capacitor.

  However, conductive polymers generally have operational problems due to being insoluble and infusible, and the polymer obtained by chemical oxidative polymerization is in the form of fine particles, so that it cannot be used as it is. Was.

For conductive polymer materials with high electrical conductivity that have been developed so far, there are methods to improve the electrical conductivity by increasing the orientation by a mechanical method such as stretching, but in the micro region Stretch orientation cannot be applied simply. There is also a technique to increase the regularity of polymerization of conductive polymers by electromagnetic techniques using electric fields or magnetic fields, etc., but generally requires special equipment, and there are problems such as cost for industrial use. Have.
In order to solve these problems, various efforts have been made from the viewpoint of material development.

  In Japanese Patent Laid-Open No. 1-313521 (Patent Document 1), a specific 3,4-di-substituted polythiophene has high conductivity, and a 3,4-di-substituted polythiophene is applied directly on a substrate. A technique for providing antistatic properties to a substrate that can be produced by chemical oxidation using a normal oxidizing agent and that transmits little or no current is disclosed. However, in the polymerization with 3,4-di-substituted polythiophene alone, the polymerization rate is slow and sufficient conductivity is not obtained.

  Japanese Patent Laid-Open No. 9-268258 (Patent Document 2) discloses a conductive monomer mainly composed of a polymer having a conjugated double bond obtained by chemical polymerization, in the case where oxide fine particles are combined, and a polymerizable monomer. Is adsorbed on the surface of the insolubilized material, and because the layer is thin, it is easy to obtain a polymer with high structure regularity, and it is suggested that the performance is improved by the thin layer polymerization method. However, since the oxide fine particles to be added are additives as a third component, it is premised that they remain in the conductive composition even after cleaning. Even if they contribute to improving the performance of the thin film as a whole, As a result, the original conductivity is impaired, and there is a concern that the performance of the bulk is deteriorated.

  Japanese Patent Application Laid-Open No. 11-292957 (Patent Document 3) discloses that a conductive monomer represented by another hetero five-membered ring compound is oxidatively polymerized in the presence of the hetero five-membered ring compound and is conductive to environmental changes. Discloses a method for producing conductive fine particles having various particle diameters in which is stable. Examples of suitably used compounds include a long-chain ethyleneoxy group in the side chain, but sufficient conductivity has not been obtained, and a description referring to a polymerization promoting effect by using a pyrrole compound as in the present invention There is no.

  In JP-A-3-7715 (Patent Document 4), an oxidative coupling polymerization of an aromatic derivative selected from a benzene derivative, a pyrrole derivative, and a thiophene derivative with oxygen using a catalyst in the presence of an acid at normal temperature, normal pressure, and the like. Is disclosed under mild conditions, but in the embodiment, the polymerization has several tens of hours, suggesting that a high oxygen partial pressure is required to shorten the reaction time. The Moreover, the special metal complex is used as a catalyst, it is necessary to remove the water in an organic solvent, and it is also necessary to add an acidic component.

  Japanese Patent Application Laid-Open No. 2-98915 (Patent Document 5) discloses a technique in which a conductive polymer compound obtained by doping a polymer compound obtained by polymerizing two or more types of monomers with a dopant is used as a solid electrolyte. Has been. However, there is no description regarding detailed production conditions related to production by chemical oxidative polymerization.

  JP-A-2000-188238 (Patent Document 6) applies a mixed solution in which 3,4-ethylenedioxythiophene monomer and an oxidizing agent are dissolved in a solvent, and then 3,4-ethylenedioxythiophene monomer and an oxidizing agent. After forming a poly (3,4-ethylenedioxythiophene) layer by polymerization reaction with the poly (3,4-ethylenedioxythiophene) layer, the pyrrole monomer solution is brought into contact with the poly (3,4-ethylenedioxythiophene) layer, Poly (pyrrole) is formed by simultaneously dissolving the oxidant in the oxythiophene) layer in the pyrrole monomer and the chemical polymerization reaction between the dissolved oxidant and the pyrrole monomer to form poly (3,4-ethylenedioxythiophene). A technology for forming a conductive polymer layer in which a polypyrrole layer is combined with a polypyrrole is disclosed, but 3,4-ethylenedioxyethylene is disclosed. Fen and pyrrole are not polymerized at the same time, and the process of forming a 3,4-ethylenedioxythiophene layer and the process of compounding polypyrrole are separated. There is no difference from the present invention.

Japanese Patent Laid-Open No. 1-313521 JP 9-268258 A Japanese Patent Laid-Open No. 11-292957 Japanese Patent Laid-Open No. 3-7715 Japanese Unexamined Patent Publication No. 2-98915 JP 2000-188238 A

  An object of the present invention is to provide a thiophene-based π-conjugated copolymer capable of obtaining high conductivity, and to provide a production method capable of manufacturing the π-conjugated copolymer under mild conditions. An object of the π-conjugated copolymer is to provide a capacitor used as a solid electrolyte.

  The inventors of the present invention polymerize a thiophene compound in the presence of a pyrrole compound, thereby promoting the polymerization of the thiophene compound, forming a copolymer with the pyrrole compound and further increasing the doping. The present invention was completed by finding that a π-conjugated copolymer having conductivity was obtained.

  That is, the present invention relates to the following π-conjugated copolymer, a production method thereof, a structure coated with the copolymer, a solid electrolytic capacitor using the copolymer as a solid electrolyte, and a production method thereof.

（式中、Ｒ¹、Ｒ²、Ｒ⁴及びＲ⁵はそれぞれ独立して水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価の基を表わし、Ｒ¹とＲ²、Ｒ⁴とＲ⁵はそれぞれ互いに任意の位置で結合して、少なくとも１つ以上の３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はカルボニル、エーテル、エステル、アミド、スルフィド、スルフィニル、スルホニル、イミノ結合を任意に含んでもよく、前記環状構造を形成する炭化水素は、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる基を有していてもよく、
Ｒ³は水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価基を表わし、
ｍ及びｎはπ共役系共重合体中の組成比を表わし、ｍ＋ｎ＝１でかつ、０＜ｍ≦０．７５である。）で示されるピロール系ユニットとチオフェン系ユニットを含むπ共役系共重合体。
２．一般式（II）

（式中、Ｒ¹、Ｒ²、Ｒ⁴及びＲ⁵はそれぞれ独立して水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価の基を表わし、Ｒ¹とＲ²、Ｒ⁴とＲ⁵はそれぞれ互いに任意の位置で結合して、少なくとも１つ以上の３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はカルボニル、エーテル、エステル、アミド、スルフィド、スルフィニル、スルホニル、イミノ結合を任意に含んでもよく、前記環状構造を形成する炭化水素は、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる基を有していてもよく、
Ｒ³は水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級または３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価基を表わし、
ｍ及びｎはπ共役系共重合体中の組成比を表わし、ｍ＋ｎ＝１でかつ、０＜ｍ≦０．７５であり、Ｚはドーパント能を有する対アニオンを表わす。）で示されるピロール系ユニットとチオフェン系ユニットを含み、電気化学的及び／または化学的にドーピングされた構造を有することを特徴とするπ共役系共重合体。
３．ピロール系ユニットが、一般式（Ｉ）中のＲ¹及びＲ²がそれぞれ独立して、水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子及びシアノ基からなる群から選ばれる一価の基を表わすか、またはＲ¹とＲ²は任意の位置で結合して３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はエーテル及び／またはスルホニル結合を任意に含んでもよく、Ｒ³が水素原子を表わすユニットである前記１に記載のπ共役系共重合体。
４．ピロール系ユニットがピロールである前記３に記載のπ共役系共重合体。
５．ピロール系ユニットが、一般式（II）中のＲ¹及びＲ²がそれぞれ独立して、水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子及びシアノ基からなる群から選ばれる一価の基を表わすか、またはＲ¹とＲ²は任意の位置で結合して３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はエーテル及び／またはスルホニル結合を任意に含んでもよく、Ｒ³が水素原子を表わすユニットであり、電気化学的及び／または化学的にドーピングされた構造を有する前記２に記載のπ共役系共重合体。
６．ピロール系ユニットがピロールである前記５に記載のπ共役系共重合体。
７．チオフェン系ユニットが、一般式（Ｉ）中のＲ⁴及びＲ⁵がそれぞれ独立して、水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子及びシアノ基からなる群から選ばれる一価の基を表わすか、またはＲ⁴とＲ⁵は任意の位置で結合して３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はエーテル及び／またはスルホニル結合を任意に含んでもよいユニットである前記１に記載のπ共役系共重合体。
８．チオフェン系ユニットが３，４−エチレンジオキシチオフェンである前記７に記載のπ共役系共重合体。
９．チオフェン系ユニットが一般式（II）中のＲ⁴及びＲ⁵がそれぞれ独立して、水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子及びシアノ基からなる群から選ばれる一価の基を表わすか、またはＲ⁴とＲ⁵は任意の位置で結合して３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はエーテル及び／またはスルホニル結合を任意に含んでもよい電気化学的及び／または化学的にドーピングされた構造を有する前記２に記載のπ共役系共重合体。
１０．チオフェン系ユニットが３，４−エチレンジオキシチオフェンである前記９に記載のπ共役系共重合体。
１１．電気伝導度が５Ｓ／ｃｍ以上である前記２、５、６、９及び１０のいずれかに記載のπ共役系共重合体。
１２．一般式（III）

（式中、Ｒ¹〜Ｒ³は前記１と同じ意味を表す。）で示されるピロール系化合物と一般式（IV）

（式中、Ｒ⁴及びＲ⁵は前記１と同じ意味を表す。）で示されるチオフェン系化合物を、酸化剤の存在下、化学酸化重合により６０℃以下の重合温度で共重合することを特徴とする前記１または２に記載のπ共役系共重合体の製造方法。
１３．ドーパント能を有する対アニオンを含む化合物を存在させる前記１２に記載のπ共役系共重合体の製造方法。
１４．ピロール系化合物がピロールである前記１２または１３に記載のπ共役系共重合体の製造方法。
１５．チオフェン系化合物が３，４−エチレンジオキシチオフェンである前記１２または１３に記載のπ共役系共重合体の製造方法。
１６．酸化剤が鉄塩類もしくは過硫酸塩を含む前記１２または１３に記載のπ共役系共重合体の製造方法。
１７．ドーパント能を有する対アニオンを含む化合物が有機スルホン酸化合物である前記１３に記載のπ共役系共重合体の製造方法。
１８．重合溶媒としてイソプロパノールと水の混合溶媒を使用する前記１２または１３に記載のπ共役系共重合体の製造方法。
１９．重合温度が３０℃以下である前記１２または１３に記載のπ共役系共重合体の製造方法。
２０．弁作用金属を電解酸化して得られる酸化皮膜の表面が前記１乃至１１のいずれかに記載のπ共役系共重合体によって被覆されていることを特徴とする構造体。
２１．弁作用金属が、アルミニウム、ケイ素、タンタル、ニオブ、チタン及びジルコニウムから選択される少なくともいずれか一種を含む前記２０に記載の構造体。
２２．前記１乃至１１のいずれかに記載のπ共役系共重合体を固体電解質とすることを特徴とする固体電解コンデンサ。
２３．多孔質で弁作用を有する金属の誘電体皮膜上にπ共役系重合体からなる固体電解質層を設ける固体電解コンデンサの製造方法において、前記誘電体皮膜上で、
一般式（III）

（式中、Ｒ¹〜Ｒ³は前記１と同じ意味を表す。）で示されるピロール系化合物と、
一般式（IV）

（式中、Ｒ⁴及びＲ⁵は前記１と同じ意味を表す。）で示されるチオフェン系化合物を、重合開始能を有する酸化剤の単独溶液または前記酸化剤とドーパント能を有する対アニオンを含む電解質の混合液を用いて重合して前記誘電体皮膜上にπ共役系共重合体を形成する工程を含むことを特徴とする固体電解コンデンサの製造方法。
２４．−３０℃〜４０℃の温度範囲で重合する前記２３に記載の固体電解コンデンサの製造方法。
２５．相対湿度５％〜７０％の雰囲気下で重合する前記２３に記載の固体電解コンデンサの製造方法。
２６．多孔質で弁作用を有する金属がアルミニウム、ケイ素、タンタル、ニオブ、チタン及びジルコニウムから選択される少なくともいずれか一種を含む前記２３に記載の固体電解コンデンサの製造方法。
２７．ピロール系化合物が、一般式（III）

（式中、Ｒ¹〜Ｒ³は前記３と同じ意味を表わす。）であり、チオフェン系化合物が、一般式（IV）

（式中、Ｒ⁴及びＲ⁵は前記７と同じ意味を表わす。）である前記２３に記載の固体電解コンデンサの製造方法。
２８．ピロール系化合物がピロールであり、チオフェン系化合物が、３，４−エチレンジオキシチオフェンである前記２３に記載の固体電解コンデンサの製造方法。
２９．重合開始能を有する酸化剤が鉄塩類もしくは過硫酸塩を含む前記２３に記載の固体電解コンデンサの製造方法。
３０．ドーパント能を有する対アニオンを含む電解質が有機スルホン酸化合物を含む前記２３に記載の固体電解コンデンサの製造方法。
３１．複数回重合する工程を含む前記２３に記載の固体電解コンデンサの製造方法。
３２．誘電体皮膜上に形成される固体電解質層の最大厚みが１０μｍ〜２００μｍである前記２３に記載の固体電解コンデンサの製造方法。 1. Formula (I)

(In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Linear or branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, 2 Represents a monovalent group selected from the group consisting of a ^primary or tertiary amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent, and R ¹ and R ² , R ⁴ and R ⁵ are each in any position To form a cyclic structure of at least one or more 3 to 7-membered saturated or unsaturated hydrocarbons, which carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl, An imino bond may be optionally included, and the hydrocarbon forming the cyclic structure is a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched chain having 1 to 10 carbon atoms, or Branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, secondary or tertiary It may have a group selected from the group consisting of an amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent,
R ³ is a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms, carbon number 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms, nitro groups, cyano groups, primary, secondary or tertiary amino groups, trihalomethyl groups, phenyl groups and substituents. Represents a monovalent group selected from the group consisting of having phenyl groups,
m and n represent the composition ratio in the π-conjugated copolymer, and m + n = 1 and 0 <m ≦ 0.75. A π-conjugated copolymer comprising a pyrrole unit and a thiophene unit represented by
2. Formula (II)

(In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Linear or branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, 2 Represents a monovalent group selected from the group consisting of a ^primary or tertiary amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent, and R ¹ and R ² , R ⁴ and R ⁵ are each in any position To form a cyclic structure of at least one or more 3 to 7-membered saturated or unsaturated hydrocarbons, which carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl, An imino bond may be optionally included, and the hydrocarbon forming the cyclic structure is a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched chain having 1 to 10 carbon atoms, or Branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, secondary or tertiary It may have a group selected from the group consisting of an amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent,
R ³ is a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms, carbon number 1-10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms, nitro groups, cyano groups, primary, secondary or tertiary amino groups, trihalomethyl groups, phenyl groups and substituents Represents a monovalent group selected from the group consisting of having phenyl groups,
m and n represent the composition ratio in the π-conjugated copolymer, m + n = 1 and 0 <m ≦ 0.75, and Z represents a counter anion having a dopant ability. A π-conjugated copolymer comprising a pyrrole unit and a thiophene unit represented by formula (II) and having an electrochemically and / or chemically doped structure.
3. In the pyrrole unit, R ¹ and R ² in the general formula (I) are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, or 1 carbon atom. Selected from the group consisting of 10 to 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups. R ¹ and R ² may be bonded at any position to form a 3- to 7-membered saturated or unsaturated hydrocarbon cyclic structure, which may be ether and / or 2. The π-conjugated copolymer according to 1 above, which may optionally contain a sulfonyl bond, and R ³ is a unit representing a hydrogen atom.
4). 4. The π-conjugated copolymer according to 3 above, wherein the pyrrole unit is pyrrole.
5). Pyrrole units, in the general formula (II) R ¹ and R ² in are each independently a hydrogen atom, a linear or branched, saturated or unsaturated alkyl group having 1 to 10 carbon atoms, atoms 1 Selected from the group consisting of 10 to 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups. R ¹ and R ² may be bonded at any position to form a 3- to 7-membered saturated or unsaturated hydrocarbon cyclic structure, which may be ether and / or ^3. The π-conjugated copolymer according to 2 above, which may optionally contain a sulfonyl bond, R ³ is a unit representing a hydrogen atom, and has an electrochemically and / or chemically doped structure.
6). 6. The π-conjugated copolymer according to 5 above, wherein the pyrrole unit is pyrrole.
7). In the thiophene unit, R ⁴ and R ^{5 in} formula (I) are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, 1 carbon atom. Selected from the group consisting of 10 to 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups. R ⁴ and R ⁵ may be bonded at any position to form a cyclic structure of a 3- to 7-membered saturated or unsaturated hydrocarbon, and the cyclic structure may be ether and / or 2. The π-conjugated copolymer according to 1 above, which is a unit optionally containing a sulfonyl bond.
8). 8. The π-conjugated copolymer according to 7, wherein the thiophene unit is 3,4-ethylenedioxythiophene.
9. In the thiophene unit, R ⁴ and R ⁵ in the general formula (II) are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Selected from the group consisting of 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups Represents a monovalent group, or R ⁴ and R ⁵ are bonded at any position to form a cyclic structure of a 3- to 7-membered saturated or unsaturated hydrocarbon, which is ether and / or sulfonyl 3. The π-conjugated copolymer according to 2 above, which has an electrochemically and / or chemically doped structure that may optionally contain a bond.
10. 10. The π-conjugated copolymer according to 9 above, wherein the thiophene unit is 3,4-ethylenedioxythiophene.
11. 11. The π-conjugated copolymer according to any one of 2, 5, 6, 9, and 10 having an electric conductivity of 5 S / cm or more.
12 General formula (III)

(Wherein R ^{1 to} R ³ represent the same meaning as in the above 1) and the general formula (IV)

(Wherein R ⁴ and R ⁵ represent the same meaning as in the above 1), the thiophene compound represented by 1 is copolymerized by chemical oxidative polymerization at a polymerization temperature of 60 ° C. or lower in the presence of an oxidizing agent The method for producing a π-conjugated copolymer according to 1 or 2 above.
13. 13. The method for producing a π-conjugated copolymer as described in 12 above, wherein a compound containing a counter anion having a dopant ability is present.
14 14. The method for producing a π-conjugated copolymer according to 12 or 13 above, wherein the pyrrole compound is pyrrole.
15. 14. The method for producing a π-conjugated copolymer according to 12 or 13, wherein the thiophene compound is 3,4-ethylenedioxythiophene.
16. 14. The method for producing a π-conjugated copolymer according to 12 or 13 above, wherein the oxidizing agent contains an iron salt or a persulfate.
17. 14. The method for producing a π-conjugated copolymer according to 13, wherein the compound containing a counter anion having a dopant ability is an organic sulfonic acid compound.
18. 14. The method for producing a π-conjugated copolymer according to 12 or 13 above, wherein a mixed solvent of isopropanol and water is used as a polymerization solvent.
19. 14. The method for producing a π-conjugated copolymer according to 12 or 13, wherein the polymerization temperature is 30 ° C. or lower.
20. A structure characterized in that the surface of an oxide film obtained by electrolytic oxidation of a valve action metal is coated with the π-conjugated copolymer described in any one of 1 to 11 above.
21. 21. The structure according to 20, wherein the valve action metal includes at least one selected from aluminum, silicon, tantalum, niobium, titanium, and zirconium.
22. A solid electrolytic capacitor comprising the π-conjugated copolymer according to any one of 1 to 11 as a solid electrolyte.
23. In the method of manufacturing a solid electrolytic capacitor in which a solid electrolyte layer made of a π-conjugated polymer is provided on a porous dielectric metal film having a valve action, on the dielectric film,
General formula (III)

(Wherein R ^{1 to} R ³ represent the same meaning as in the above 1),
Formula (IV)

(Wherein, R ⁴ and R ⁵ represent. As defined above 1) comprises a single solution or counter anion having the oxidizing agent and a dopant ability of oxidizing agent having a thiophene-based compound, polymerization initiating ability represented by A method for producing a solid electrolytic capacitor, comprising a step of polymerizing using a mixed solution of an electrolyte to form a π-conjugated copolymer on the dielectric film.
24. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the polymerization is performed in a temperature range of −30 ° C. to 40 ° C.
25. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein polymerization is performed in an atmosphere having a relative humidity of 5% to 70%.
26. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the porous metal having a valve action includes at least one selected from aluminum, silicon, tantalum, niobium, titanium and zirconium.
27. The pyrrole compound has the general formula (III)

(Wherein R ^{1 to} R ³ represent the same meaning as in the above 3), and the thiophene compound is represented by the general formula (IV)

24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein R ⁴ and R ⁵ represent the same meaning as in 7.
28. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the pyrrole compound is pyrrole and the thiophene compound is 3,4-ethylenedioxythiophene.
29. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the oxidizing agent having a polymerization initiating ability contains an iron salt or a persulfate.
30. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the electrolyte containing a counter anion having a dopant ability contains an organic sulfonic acid compound.
31. 24. The method for producing a solid electrolytic capacitor as described in 23 above, comprising a step of polymerizing a plurality of times.
32. 24. The method for producing a solid electrolytic capacitor as described in 23 above, wherein the maximum thickness of the solid electrolyte layer formed on the dielectric film is 10 μm to 200 μm.

  The present invention provides a novel π-conjugated copolymer having high conductivity, a method for producing the same, and a capacitor excellent in high-frequency characteristics using the copolymer.

BEST MODE FOR CARRYING OUT THE INVENTION

この共重合体は、下記一般式（III）で示されるピロール系化合物と式（IV）で示されるチオフェン系化合物をモノマーとして、酸化剤の存在下に共重合して得られ、ピロール系化合物及びチオフェン系化合物が、共重合体中でそれぞれのユニットを構成する。

（式中、Ｒ¹、Ｒ²、Ｒ⁴及びＲ⁵はそれぞれ独立して水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価の基を表わし、Ｒ¹とＲ²、Ｒ⁴とＲ⁵はそれぞれ互いに任意の位置で結合して、少なくとも１つ以上の３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はカルボニル、エーテル、エステル、アミド、スルフィド、スルフィニル、スルホニル、イミノ結合を任意に含んでもよく、前記環状構造を形成する炭化水素は、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる基を有していてもよく、
Ｒ³は水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級または３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価基を表わす。） Hereinafter, the present invention will be described in detail.
The present invention is a π-conjugated copolymer containing, as repeating units, a structure represented by a pyrrole unit and a thiophene unit represented by the following general formula (I).

This copolymer is obtained by copolymerization in the presence of an oxidizing agent using a pyrrole compound represented by the following general formula (III) and a thiophene compound represented by formula (IV) as monomers, and the pyrrole compound and A thiophene compound constitutes each unit in the copolymer.

(In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Linear or branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, 2 Represents a monovalent group selected from the group consisting of a ^primary or tertiary amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent, and R ¹ and R ² , R ⁴ and R ⁵ are each in any position To form a cyclic structure of at least one or more 3 to 7-membered saturated or unsaturated hydrocarbons, which carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl, An imino bond may be optionally included, and the hydrocarbon forming the cyclic structure is a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched chain having 1 to 10 carbon atoms, or Branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, secondary or tertiary It may have a group selected from the group consisting of an amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent,
R ³ is a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms, carbon number 1-10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms, nitro groups, cyano groups, primary, secondary or tertiary amino groups, trihalomethyl groups, phenyl groups and substituents Represents a monovalent group selected from the group consisting of phenyl groups. )

  In addition, the present invention provides a π conjugate having an electrochemically and / or chemically doped structure containing a structure represented by the pyrrole unit and thiophene unit represented by the following general formula (II) as a repeating unit. Copolymer. This copolymer is obtained by electrochemically and / or chemically doping the π-conjugated copolymer represented by the general formula (I), and the resulting positive charge such as cation radical or cation is It is electrically neutralized by a counter anion having a dopant ability, indicating that the electric charge can be transferred by applying an electric field.

（式中、Ｒ¹、Ｒ²、Ｒ⁴及びＲ⁵はそれぞれ独立して水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価の基を表わし、Ｒ¹とＲ²、Ｒ⁴とＲ⁵はそれぞれ互いに任意の位置で結合して、少なくとも１つ以上の３〜７員環の飽和または不飽和炭化水素の環状構造を形成し、その環状構造はカルボニル、エーテル、エステル、アミド、スルフィド、スルフィニル、スルホニル、イミノ結合を任意に含んでもよく、前記環状構造を形成する炭化水素は、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる基を有していてもよく、
Ｒ³は水素原子、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキル基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルコキシ基、炭素数１〜１０の直鎖状もしくは分岐状の飽和もしくは不飽和のアルキルエステル基、ハロゲン原子、ニトロ基、シアノ基、１級、２級もしくは３級アミノ基、トリハロメチル基、フェニル基及び置換基を有するフェニル基からなる群から選ばれる一価基を表わし、
ｍ及びｎはπ共役系共重合体中の組成比を表わし、ｍ＋ｎ＝１でかつ、０＜ｍ≦０．７５であり、Ｚはドーパント能を有する対アニオンを表わす。）

(In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Linear or branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, 2 Represents a monovalent group selected from the group consisting of a ^primary or tertiary amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent, and R ¹ and R ² , R ⁴ and R ⁵ are each in any position To form a cyclic structure of at least one or more 3 to 7-membered saturated or unsaturated hydrocarbons, which carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl, An imino bond may be optionally included, and the hydrocarbon forming the cyclic structure is a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched chain having 1 to 10 carbon atoms, or Branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, secondary or tertiary It may have a group selected from the group consisting of an amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent,
R ³ is a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms, carbon number 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms, nitro groups, cyano groups, primary, secondary or tertiary amino groups, trihalomethyl groups, phenyl groups and substituents Represents a monovalent group selected from the group consisting of having phenyl groups,
m and n represent the composition ratio in the π-conjugated copolymer, m + n = 1 and 0 <m ≦ 0.75, and Z represents a counter anion having a dopant ability. )

  Examples of the pyrrole compound that is a raw material of the π-conjugated copolymer include pyrrole, 3-methylpyrrole, 3-ethylpyrrole, 3-propylpyrrole, 3-butylpyrrole, 3-pentylpyrrole, 3-hexylpyrrole, 3- Heptylpyrrole, 3-octylpyrrole, 3-nonylpyrrole, 3-decylpyrrole, 3-fluoropyrrole, 3-chloropyrrole, 3-bromopyrrole, 3-cyanopyrrole, 3,4-dimethylpyrrole, 3,4-diethyl Derivatives such as pyrrole, 3,4-butylene pyrrole, 3,4-methylenedioxypyrrole, and 3,4-ethylenedioxypyrrole can be exemplified. These compounds can be prepared commercially or by known methods, but are not limited to these in the present invention.

  Examples of thiophene compounds include thiophene, 3-methylthiophene, 3-ethyloffene, 3-propylthiophene, 3-butylthiophene, 3-pentylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3-octylthiophene, 3- Nonylthiophene, 3-decylthiophene, 3-fluorothiophene, 3-chlorothiophene, 3-bromothiophene, 3-cyanothiophene, 3,4-dimethylthiophene, 3,4-diethylthiophene, 3,4-butylenethiophene, 3 , 4-methylenedioxythiophene, 3,4-ethylenedioxythiophene and the like.

These compounds can generally be prepared by commercially available compounds or by known methods (for example, Synthetic Metals, 1986, Vol. 15, p. 169), but the present invention is not limited to these. In addition, a compound having a 1,3-dihydropolycyclic sulfide (also known as 1,3-dihydrobenzo [c] thiophene) skeleton, a compound having a 1,3-dihydronaphtho [2,3-c] thiophene skeleton, A compound having a 3-dihydroanthra [2,3-c] thiophene skeleton and a compound having a 1,3-dihydronaphthaseno [2,3-c] thiophene skeleton can also be exemplified, and known methods such as JP-A-8 It can be prepared by the method described in Japanese Patent No. 3156. The condensed ring may optionally contain nitrogen or N-oxide, such as 1,3-dihydrothieno [3,4-b] quinoxaline or 1,3-dihydrothieno [3,4-b] quinoxaline-4-oxide 1,3-dihydrothieno [3,4-b] quinoxaline-4,9-dioxide and the like.
Two or more compounds selected from the above compound group can be used in combination to form a ternary or multi-component copolymer.

  In the present invention, useful examples of the linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, and t-butyl group. Pentyl group, hexyl group, octyl group, vinyl group, allyl group, 1-butenyl group, 3-butenyl group, 5-hexenyl group and the like. In addition, useful examples of the linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a pentoxy group, and a hexyloxy group. And octyloxy group. In addition, useful examples of the linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms include methyl ester group, ethyl ester group, propyl ester group, isopropyl ester group, butyl ester group, pentyl Examples thereof include, but are not limited to, an ester group, a hexyl ester group, and an octyl ester group.

  In the present invention, specific examples of the halogen atom include chlorine, bromine, fluorine and the like. Specific examples of the primary, secondary or tertiary amino group include a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, and a dimethylamino group. Specific examples of the trihalomethyl group include a trichloromethyl group, a tribromomethyl group, and a trifluoromethyl group. Specific examples of the phenyl group and the phenyl group having a substituent include a phenyl group substituted with a halogen group such as chlorine, bromine and fluorine, a tolyl group and a biphenyl group.

  In the method for producing a π-conjugated copolymer of the present invention, the pyrrole compound has an effect of promoting the polymerization of the thiophene compound. The pyrrole compound itself can form a π-conjugated system together with other monomers or separately in the π-conjugated copolymer. As the pyrrole compound, those having a function of further improving the electrical conductivity of the π-conjugated copolymer are preferably used. Specifically, a compound having a higher polymerization activity than the thiophene compound is used for the oxidizing agent used, and more specifically, assists the polymerization even under polymerization conditions where the thiophene compound alone cannot be polymerized. Those having a promoting effect are used.

  The oxidation potential of the thiophene compound is preferably between the reduction potential of the oxidizing agent used and the oxidation potential of the pyrrole compound. This is because it is considered that the pyrrole compound oxidized by the polymerization oxidant reacts with the thiophene compound as a polymerization initiator, and the activation of the thiophene compound, which was originally inactive polymerization conditions, appears.

  The recommended composition ratio of the π-conjugated copolymer of the present invention is affected by the type and reaction conditions of the pyrrole compound and thiophene compound used, particularly the polymerization time and the presence or absence of an external dopant. A preferred composition ratio is 0 <m <0.8, more preferably 0.01 <m ≦ 0.75. When the composition ratio of the obtained π-conjugated copolymer is m ≧ 0.8, the electric conductivity is lowered, and in the region of 0.75 <m <0.8, it is very influenced by the reaction conditions, A slight difference in composition ratio affects electrical conductivity.

The oxidizing agent used in the present invention may be any oxidizing agent that can sufficiently perform the dehydrogenating two-electron oxidation reaction or the dehydrogenating four-electron oxidation reaction. Compounds that are industrially inexpensive and easy to handle in production are preferred. Specific examples include iron salts such as FeCl ₃ , FeClO ₄ , Fe (organic acid anion) salts, or anhydrous aluminum chloride / cuprous chloride, alkali metal persulfates, ammonium persulfates, peroxides, peroxides Manganese such as potassium manganate, quinones such as 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), tetrachloro-1,4-benzoquinone, tetracyano-1,4-benzoquinone, Examples include halogens such as iodine and bromine, peracids, sulfuric acid, fuming sulfuric acid, sulfur trioxide, sulfonic acids such as chlorosulfuric acid, fluorosulfuric acid and amidosulfuric acid, ozone and the like, and combinations of these oxidants.

  Among the oxidizing agents, oxidizing agents containing iron salts, cuprous chlorides, alkali persulfates, ammonium persulfates, manganic acids, and quinones can be preferably used. Among these, iron salts and ammonium persulfate salts with little mixing of various impurities are particularly preferable.

In the method for producing a π-conjugated copolymer of the present invention, the counter anion having a dopant ability that coexists as necessary is an oxidant anion (reduced form of the oxidant) produced from the oxidant. Examples thereof include electrolyte compounds having other anionic electrolytes. Specifically, for example, a halogenated anion of a group 5B element such as PF ₆ ⁻ , SbF ₆ ⁻ , AsF ₆ ⁻ , a halogenated anion of a group 3B element such as BF ₄ ⁻ , I ⁻ (I ₃ ⁻ ), Br ^-, Cl ^- such halogen anion, ClO ₄ of ^- halogen, such as anion, AlCl ₄ ^- and FeCl ₄ ^-, SnCl ₅ ^- such Lewis acid anion such or NO _3, ^-, SO ₄ ^2- of such inorganic acid anion Or p-toluenesulfonic acid or naphthalenesulfonic acid, an alkyl-substituted sulfonic acid having 1 to 5 carbon atoms, an organic sulfonic acid anion such as CH ₃ SO ₃ ⁻ or CF ₃ SO ₃ ^— , or CF ₃ COO ⁻ , C ₆ H ₅ COO ^- can be exemplified such as a protonic acid anions such as carboxylate anions. Similarly, polymer electrolyte anions such as polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, polyvinyl sulfonic acid, polyvinyl sulfuric acid, poly-α-methyl sulfonic acid, polyethylene sulfonic acid, and polyphosphoric acid can be cited. It is not necessarily limited.

However, preferred examples include high-molecular or low-molecular organic sulfonic acid compounds or polyphosphoric acid, and more preferred are aryl sulfonate-based dopants. For example, salts such as benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid, anthracenesulfonic acid, anthraquinonesulfonic acid and derivatives thereof can be used.
Further, by selecting and adding an appropriate dopant, the shape of the π-conjugated copolymer obtained can be changed to a spherical shape or a needle shape.

Monomer concentration used in the present invention that varies depending on the kind and the type of solvents such substituents of compounds, generally it is preferably in the range of 10 ^-3 10 mol / L, also of 10 ^-2 5 mol / L range Is more preferable.

  The charge ratio at the start of the reaction of the pyrrole compound used in the present invention is not particularly limited because it differs depending on the type and reaction conditions, but when the sum of the molar concentrations of the pyrrole compound and the thiophene compound is 1. The charging ratio of the pyrrole compound is preferably less than 0.5, more preferably less than 0.3. When the charging ratio exceeds 0.5, the reaction of the pyrrole compound proceeds preferentially, and when the reaction time becomes long, particularly the electric conductivity of the obtained copolymer is affected. In order to further improve the electrical conductivity, it is preferable to shorten the polymerization time and add an external dopant.

  The reaction temperature depends on the reaction method and is not particularly limited, but is generally in the temperature range of −70 ° C. to 60 ° C., desirably in the range of −30 ° C. to 50 ° C., and further to the temperature of −10 ° C. to 40 ° C. A range is preferred. When the polymerization temperature is lower than −70 ° C., there are problems in practical use such as equipment and productivity, such as a slow polymerization rate. When the polymerization temperature exceeds 60 ° C., an undesirable reaction that does not form a π-conjugated system is induced, and the electric conductivity of the obtained π-conjugated copolymer is low.

  The reaction solvent used in the present invention may be any solvent that can dissolve the monomer, the oxidizing agent, or the counter anion having a dopant ability, or each of them. For example, ethers such as tetrahydrofuran, dioxane and diethyl ether, aprotic polar solvents such as dimethylformamide, acetonitrile, benzonitrile, N-methylpyrrolidone and dimethyl sulfoxide, esters such as ethyl acetate and butyl acetate, chloroform and methylene chloride Non-aromatic chlorinated solvents such as nitro compounds such as nitromethane, nitroethane, and nitrobenzene, alcohols such as methanol, ethanol, propanol, and isopropanol, or organic acids such as formic acid, acetic acid, and propionic acid, or An acid anhydride (for example, acetic anhydride), water, ketones, or a mixed solvent thereof can be used. In particular, a mixed solvent of water and alcohol is preferable, and a mixed solvent of water and isopropanol is more preferable. Further, the counter anion and the monomer having the oxidizing agent and / or dopant ability may be handled in a solvent system dissolved independently, that is, a two-component system or a three-component system.

  The electrical conductivity of the solid conductor thus produced is 1 S / cm or more, but it is 3 S / cm or more under desirable conditions, and 5 S / cm or more under more desirable conditions.

Examples of the structure having an oxide film obtained by electrolytic oxidation of the valve action metal include a foil obtained by stretching the valve action metal, a sintered body obtained by sintering the valve action metal fine powder, and the like. It is done. These structures may be subjected to a treatment for expanding the surface area such as etching.
The oxide film obtained by electrolytic oxidation of the valve action metal includes oxides containing at least one of aluminum, silicon, tantalum, niobium, titanium, and zirconium, and more specifically, aluminum oxide, tantalum oxide, niobium. Oxides, niobium alloys, niobium monoxide, niobium nitride, and the like are preferably used.

（式中、Ｒ¹〜Ｒ³は前記と同じ意味を表わす）で示されるピロール系化合物と、
一般式（IV）

（式中、Ｒ⁴及びＲ⁵は前記と同じ意味を表わす）で示されるチオフェン系化合物を、重合開始能を有する酸化剤の単独溶液または前記酸化剤とドーパント能を有する対アニオンを含む電解質の混合液を用いて重合して前記誘電体皮膜上にπ共役系共重合体を形成する工程を含むことを特徴とする。 This π-conjugated copolymer can be suitably used as a solid electrolyte for a capacitor having an oxide film obtained by electrolytic oxidation of a valve metal.
As a method for producing the solid electrolytic capacitor of the present invention, the general formula (III)

(Wherein, R ^{1 to} R ³ represent the same meaning as described above),
Formula (IV)

(Wherein R ⁴ and R ⁵ represent the same meaning as described above), a single solution of an oxidizing agent having a polymerization initiating ability or an electrolyte containing the oxidizing agent and a counter anion having a dopant ability It includes a step of polymerizing using a mixed solution to form a π-conjugated copolymer on the dielectric film.

  A basic process of polymerizing a pyrrole compound and a thiophene compound on a dielectric film using a single solution of an oxidizing agent having a polymerization initiating ability or a mixed solution of an electrolyte containing the oxidizing agent and a counter anion having a dopant ability As a pyrrole compound and a thiophene compound alone or in a solution in a solvent, impregnated with a porous structure having a dielectric film, and introduced a pyrrole compound and a thiophene compound inside the porous body Then, the polymerization reaction can be initiated by impregnating the single solution of the oxidizing agent having the polymerization initiating ability or the mixed solution of the electrolyte containing the oxidizing agent and the counter anion having the dopant ability.

  The reaction temperature when forming a π-conjugated copolymer as a solid electrolyte on the dielectric film is not particularly limited because it varies depending on the type of pyrrole compound or thiophene compound used, the type of solvent, the oxidizing agent, and the reaction method. Any temperature range in which polymerization of the pyrrole compound can be promoted may be used. Generally, -30 to 60 ° C, more preferably -10 to 40 ° C is preferable. When the temperature is lower than −30 ° C., the progress of the polymerization reaction on the porous film is slow, which is not practical, and when the temperature exceeds 60 ° C., it is preferable for the structure of the π-conjugated copolymer obtained on the porous film. Therefore, the resulting π-conjugated copolymer has low electrical conductivity.

  Relative humidity plays an important role when forming a π-conjugated copolymer as a solid electrolyte on a dielectric film. Preferably it is 5%-70%, More preferably, it is the range of 20%-50%. When the relative humidity is less than 5%, sufficient polymerization reaction on the foil does not proceed, and the yield of the obtained π-conjugated copolymer is poor, which is not practical. On the other hand, when the relative humidity exceeds 70%, the polymerization reaction proceeds, but the properties as a solid electrolyte are deteriorated in a fine region in the porous body, and the electrical conductivity is lowered.

As a method for forming a π-conjugated copolymer as a solid electrolyte on a dielectric film, a pyrrole compound and a thiophene compound may be used alone or as a solution in a solvent, and a porous film having a dielectric film may be used. After impregnating the structure and introducing a pyrrole compound and a thiophene compound into the porous body, a single solution of an oxidizing agent having a polymerization initiating ability or a mixed solution of an electrolyte containing the oxidizing agent and a counter anion having a dopant ability However, the amount of the π-conjugated copolymer obtained may not be sufficient if this step is performed only once.
Therefore, a pyrrole compound and a thiophene compound are polymerized on a dielectric oxide film using a single solution of an oxidizing agent having a polymerization initiating ability, or a mixed solution of an electrolyte containing the oxidizing agent and a counter anion having a dopant ability. The copolymer is produced and washed, or the same operation is performed again on the surface of the copolymer obtained by polymerization without washing at least about 3 times, and practically 5 times or more polymerization steps. The method of repeating is preferable. However, since it is not preferable that the solid electrolyte has a thickness more than necessary, about 5 to 30 times is sufficient. Usually, a required solid electrolyte layer can be secured about 7 to 25 times.

  For example, when the π-conjugated copolymer of the present invention is formed on an aluminum etched foil having a thickness of 100 μm, when the total thickness after formation is measured and the thickness of the foil is subtracted, the entire solid electrolyte is preferably 10 to 200. It is a micron thickness. More preferably, it is 20 to 180 microns. If it is thinner than 10 microns, the leakage current characteristic is deteriorated, and if it is thicker than 200 microns, the electrical characteristics are affected.

  It is preferable to provide a conductor layer on the solid electrolyte of the π-conjugated copolymer thus formed in order to improve electrical contact with the cathode lead terminal. For example, conductive paste, plating, metal vapor deposition, conductive resin film formation, or the like is performed. Next, a cathode lead terminal is connected and, for example, a resin mold, a resin case, a metal outer case, or an outer case such as resin dipping can be used to obtain a solid electrolytic capacitor for various uses.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited by these Examples.

Reference Example 1 : 3,4-ethylenedioxythiophene: pyrrole = 9: 1
To a 30 ml three-necked round bottom flask, 1.70 g of ammonium persulfate was weighed, 5.0 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.04 g of pyrrole and 0.48 g of 3,4-ethylenedioxythiophene were weighed, and 1.3 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.26 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. The surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Yuka Kabushiki Kaisha), and converted to electrical conductivity by multiplying the film thickness of the pellet. there were.

Reference Example 2 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3
In a 30 ml three-necked round bottom flask, 1.91 g of ammonium persulfate was weighed, 5.6 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.49 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 12.1 S / cm. there were.
FIG. 1 shows a photograph of the obtained copolymer taken with a scanning electron microscope S-900 manufactured by Hitachi, magnified 50000 times at an acceleration voltage of 6 kV.

Reference Example 3 : 3,4-ethylenedioxythiophene: pyrrole = 5: 5
2.18 g of ammonium persulfate was weighed into a 30 ml three-necked round bottom flask, 6.4 ml of water was added thereto, and the mixture was cooled to 0 ° C. while stirring in an ice bath. Separately, a sample tube was prepared, 0.16 g of pyrrole and 0.34 g of 3,4-ethylenedioxythiophene were weighed, and 1.6 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.53 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 9.4 S / cm. there were.

Example 1 : 3,4-ethylenedioxythiophene: pyrrole = 9: 1 + compound containing a counter anion having dopant ability 30 ml Three-necked round bottom flask was charged with 1.70 g of ammonium persulfate, and sodium 2-anthraquinonesulfonate was added. 36 g was added, 5.0 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.04 g of pyrrole and 0.48 g of 3,4-ethylenedioxythiophene were weighed, and 1.3 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.26 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 47 S / cm. .
FIG. 2 shows a photograph of the obtained copolymer taken using a scanning electron microscope S-900 manufactured by Hitachi at a magnification of 50000 times at an acceleration voltage of 6 kV.

Example 2 : Capacitor production 3.3 mm × 10 mm cut etched aluminum conversion foil (4V conversion product) 10 mm in the middle of the surface, the surface is divided into 4 mm and 5 mm parts, both sides are 1 mm wide A polyimide solution was applied and dried to form a separation zone between the anode portion and the cathode portion. A 3.3 mm × 4 mm portion of this etched aluminum formed foil was dipped in a 1.5 mol / L ammonium persulfate aqueous solution (referred to as Solution 1), then pulled up and dried at room temperature for 3 minutes. Subsequently, a 3.3 mm × 4 mm portion of the etched aluminum formed foil was immersed in an isopropanol solution of 0.9 mol / L 3,4-ethylenedioxythiophene and 0.1 mol / L pyrrole (referred to as Solution 2). Then, it was pulled up and oxidative polymerization was performed by leaving it in an atmosphere of 30 ° C. for 10 minutes. And after immersing in this solution 1 and immersing in solution 2 and performing oxidative polymerization 20 times, it was washed with 50 ° C. warm water for 10 minutes, then dried at 100 ° C. for 30 minutes and π The conjugated composition copolymer was coated on the dielectric film.

Next, a carbon paste and a silver paste are attached to a portion of the etched aluminum formed foil where the π-conjugated copolymer is formed, three etched aluminum formed foils are laminated, cathode lead terminals are connected, and π An anode lead terminal was connected to a portion where the conjugated copolymer was not formed by welding. Furthermore, after sealing this element with an epoxy resin, a rated voltage was applied at 125 ° C. and aging was performed for 2 hours to complete a total of 30 capacitors.
With respect to these 30 capacitors, the initial characteristics were measured for capacity and loss factor (tan δ) at 120 Hz, impedance at resonance frequency, and leakage current. The leakage current was measured 1 minute after applying the rated voltage. The measurement results were as follows.
Capacity (average value): 108 μF
tan δ (average value): 1.2%
Impedance (average value): 10 mΩ
Leakage current (average value): 0.09 μA
The defective rate was 0% when a leakage current of 1.0 μA (0.005 CV) or more was regarded as a defective product.

Furthermore, the result in the reflow test and the subsequent moisture resistance test was shown. The reflow test (also called solder heat resistance test) was evaluated by the following method. That is, 30 capacitor elements were prepared, the elements were passed for 10 seconds at a temperature of 250 ° C., this operation was repeated three times, the leakage current after 1 minute application of the rated voltage was measured, and the value was 8. An element of 0 μA (0.04 CV) or more was regarded as a defective product. In addition, the moisture resistance test was left at a high temperature and high humidity of 85 ° C. and 85% RH for 500 hours, and a leakage current value of 60 μA (0.3 CV) or more after 1 minute of application of the rated voltage was regarded as a defective product.
Leakage current after reflow test: 0.20 μA
Leakage current after moisture resistance test: 11.7 μA
In all cases, the defect rate was zero.

Reference Example 4 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter-anion having a dopant ability 30 ml Three-neck round bottom flask was charged with 1.91 g of ammonium persulfate and 0.2% sodium 2-anthraquinonesulfonate. 40 g was added, 5.6 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.62 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 38.3 S / cm. there were.

Reference Example 5 : 3,4-ethylenedioxythiophene: pyrrole = 9: 1 + compound containing counter anion having dopant ability 30 ml Three-neck round bottom flask with 1.70 g of ammonium persulfate, disodium 2,7-anthraquinone disulfonate 0.48 g of (2,7-SAQS) was added, 5.0 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.04 g of pyrrole and 0.48 g of 3,4-ethylenedioxythiophene were weighed, and 1.3 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.17 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 6.1 S / cm. there were.

Reference Example 6 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter-anion having dopant ability 30 ml Three-necked round bottom flask was charged with 1.91 g of ammonium persulfate and 0.22 sodium anthraquinonesulfonate. 40 g was added, 5.6 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 10 minutes.
After 10 minutes, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.34 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 20.3 S / cm. there were.

Reference Example 7 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter-anion having dopant ability 30 ml Three-neck round bottom flask was charged with 1.91 g of ammonium persulfate and 0.22 sodium anthraquinonesulfonate. 40 g was added, 5.6 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 30 minutes.
After 30 minutes, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.41 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 25.9 S / cm. there were.

Reference Example 8 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter-anion having dopant ability 30 ml Three-necked round bottom flask was charged with 1.91 g of ammonium persulfate, and sodium 2-anthraquinonesulfonate was added. 40 g was added, 5.6 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 150 minutes.
After 150 minutes, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.63 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 32.3 S / cm. there were.

Reference Example 9 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter-anion having a dopant ability 30 ml Three-necked round bottom flask was charged with 1.91 g of ammonium persulfate, and sodium 2-anthraquinonesulfonate was added. 40 g was added, 16.8 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 4.2 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.41 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 22.9 S / cm. there were.

Reference Example 10 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter anion having a dopant ability 30 ml Three-necked round bottom flask was charged with 1.91 g of ammonium persulfate, and sodium 2-anthraquinonesulfonate was added. 40 g was added, 2.8 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 0.7 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.49 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 28.6 S / cm. there were.
FIG. 3 shows a photograph of the obtained copolymer taken using a scanning electron microscope S-900 manufactured by Hitachi, magnified 50000 times at an acceleration voltage of 6 kV.

Reference Example 11 : 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + compound containing a counter anion having dopant ability 30 ml Three-necked round bottom flask was charged with 1.91 g of ammonium persulfate and 0.22 sodium anthraquinone sulfonate. 40 g was added, 5.6 ml of water was added thereto, and the mixture was stirred in a 40 ° C. water bath. Separately, a sample tube was prepared, 0.09 g of pyrrole and 0.42 g of 3,4-ethylenedioxythiophene were weighed, and 1.4 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution heated to 40 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.63 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. When the surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.) and converted to electrical conductivity by multiplying the thickness of the pellet, it was 5.9 S / cm. there were.

Comparative Example 1: 3,4-ethylenedioxythiophene: pyrrole = 0: 10
In a 30 ml three-necked round bottom flask, 3.41 g of ammonium persulfate was weighed, 9.9 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.50 g of pyrrole was weighed into this, and 2.5 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the polymer obtained after drying, 0.61 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. The surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.), and converted to electrical conductivity by multiplying the thickness of the pellet, it was 0.30 S / cm. there were.

Comparative Example 2: (3,4-ethylenedioxythiophene: pyrrole = 3: 7)
In a 30 ml three-necked round bottom flask, 2.54 g of ammonium persulfate was weighed, 7.4 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, prepare a sample tube, weigh 0.26 g of pyrrole as a reaction accelerator and 0.24 g of 3,4-ethylenedioxythiophene, add 1.9 ml of isopropyl alcohol, and stir to prepare a monomer solution. did. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After 2 hours, 100 ml of water was added to the reaction solution and stirred for 1 hour, followed by filtration to remove water-soluble impurities. Next, 100 ml of acetone was added to the obtained black solid and stirred for 1 hour to remove soluble components.
After drying under reduced pressure at 50 ° C. for 3 hours and measuring the mass of the copolymer obtained after drying, 0.57 g was obtained. Next, pellets having a radius of 1 cm were produced using a molding machine. The surface resistance of this pellet was measured by a four-probe method using Loresta IP MCP-250 (manufactured by Mitsubishi Oil Chemical Co., Ltd.), and converted to electrical conductivity by multiplying the thickness of the pellet to find 0.53 S / cm. there were.

Comparative Example 3: (3,4-ethylenedioxythiophene: pyrrole = 10: 0)
1.61 g of ammonium persulfate was weighed into a 30 ml three-necked round bottom flask, 4.7 ml of water was added thereto, and the mixture was cooled to 0 ° C. with stirring in an ice bath. Separately, a sample tube was prepared, 0.50 g of 3,4-ethylenedioxythiophene was weighed, and 1.2 ml of isopropyl alcohol was added and stirred to prepare a monomer solution. The monomer solution was added dropwise to an aqueous ammonium persulfate solution cooled to 0 ° C., and stirring was continued for 2 hours.
After stirring for 2 hours, the reaction solution was slightly colored in yellow, and no polymer was obtained.

Table 1 shows the elemental analysis results of the polymers obtained in Examples 1 and 2, Reference Examples 1 to 11 and Comparative Examples 1 to 3, and the composition ratio of the pyrrole compound, thiophene compound and dopant. In addition, the percentage of a dopant is a value with respect to the sum total of a pyrrole type compound and a thiophene type compound.

Example 3 :
A capacitor was produced and evaluated in the same manner as in Example 2 except that the isopropanol solution concentrations of 3,4-ethylenedioxythiophene and pyrrole were 0.95 mol / L and 0.05 mol / L, respectively. The results are summarized in Tables 3 to 5 below.

Reference Example 12 :
A capacitor was manufactured and evaluated in the same manner as in Example 2 except that the isopropanol solution concentrations of 3,4-ethylenedioxythiophene and pyrrole were 0.7 mol / L and 0.3 mol / L, respectively. The results are summarized in Tables 3 to 5 below.

Example 4 :
A capacitor was produced and evaluated in the same manner as in Example 2 except that the polymerization temperature was 40 ° C. The results are summarized in Tables 3 to 5 below.

Example 5 :
A capacitor was produced and evaluated in the same manner as in Example 2 except that the polymerization temperature was 26 ° C. and the number of polymerizations was 10. The results are summarized in Tables 3 to 5 below.

Reference Example 13 :
A capacitor was produced and evaluated in the same manner as in Example 2 except that the polymerization temperature was 26 ° C. and the number of polymerizations was 14 times. The results are summarized in Tables 3 to 5 below.

  The π-conjugated copolymer obtained by the present invention is useful as various conductive materials such as electrodes, sensors, electronic display elements, photoelectric conversion elements, antistatic materials, optical materials, and various electronic parts, which require high workability in the electronics field. It is.

4 is an electron micrograph of a compound containing 3,4-ethylenedioxythiophene: pyrrole = 7: 3 obtained in Reference Example 2 . 3 is an electron micrograph of a compound containing a counter anion having 3,4-ethylenedioxythiophene: pyrrole = 9: 1 + dopant ability obtained in Example 1. FIG. 4 is an electron micrograph of a compound containing a counter anion having 3,4-ethylenedioxythiophene: pyrrole = 7: 3 + dopant ability obtained in Reference Example 10 .

Claims (24)

Formula (II)

(In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Linear or branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, 2 Represents a monovalent group selected from the group consisting of a ^primary or tertiary amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent, and R ¹ and R ² , R ⁴ and R ⁵ are each in any position To form a cyclic structure of at least one or more 3 to 7-membered saturated or unsaturated hydrocarbons, which carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl, An imino bond may be optionally included, and the hydrocarbon forming the cyclic structure is a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched chain having 1 to 10 carbon atoms, or Branched saturated or unsaturated alkoxy group, linear or branched saturated or unsaturated alkyl ester group having 1 to 10 carbon atoms, halogen atom, nitro group, cyano group, primary, secondary or tertiary It may have a group selected from the group consisting of an amino group, a trihalomethyl group, a phenyl group and a phenyl group having a substituent,
R ³ is a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, a linear or branched saturated or unsaturated alkoxy group having 1 to 10 carbon atoms, carbon number 1-10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms, nitro groups, cyano groups, primary, secondary or tertiary amino groups, trihalomethyl groups, phenyl groups and substituents Represents a monovalent group selected from the group consisting of having phenyl groups,
m and n represent the composition ratio in the π-conjugated copolymer, m + n = 1 and 0.05 <m ≦ 0.1, and Z is a 2-anthraquinone sulfonate anion . A π-conjugated copolymer comprising a pyrrole unit and a thiophene unit represented by formula (II) and having an electrochemically and / or chemically doped structure. In the pyrrole unit, R ¹ and R ² in the general formula (II) are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, or 1 carbon atom. Selected from the group consisting of 10 to 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups. R ¹ and R ² may be bonded at any position to form a 3- to 7-membered saturated or unsaturated hydrocarbon cyclic structure, which may be ether and / or The π-conjugated copolymer according to claim 1, which may optionally contain a sulfonyl bond, wherein R ³ is a unit representing a hydrogen atom, and has an electrochemically and / or chemically doped structure.   The π-conjugated copolymer according to claim 2, wherein the pyrrole unit is pyrrole. In the thiophene unit, R ⁴ and R ⁵ in the general formula (II) are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, Selected from the group consisting of 10 linear or branched saturated or unsaturated alkoxy groups, 1 to 10 linear or branched saturated or unsaturated alkyl ester groups, halogen atoms and cyano groups Represents a monovalent group, or R ⁴ and R ⁵ are bonded at any position to form a cyclic structure of a 3- to 7-membered saturated or unsaturated hydrocarbon, which is ether and / or sulfonyl The π-conjugated copolymer according to claim 1, having an electrochemically and / or chemically doped structure that may optionally contain a bond.   The π-conjugated copolymer according to claim 4, wherein the thiophene unit is 3,4-ethylenedioxythiophene.   The π-conjugated copolymer according to any one of claims 1 to 5, having an electric conductivity of 5 S / cm or more. General formula (III)

(Wherein R ^{1 to} R ³ represent the same meaning as in claim 1) and a pyrrole compound represented by the general formula (IV)

(Wherein R ⁴ and R ⁵ represent the same meaning as in claim 1), the thiophene compound represented by the chemical oxidation polymerization in the presence of a compound containing an oxidizing agent and a 2-anthraquinone sulfonate anion at 60 ° C. The method for producing a π-conjugated copolymer according to claim 1, wherein the copolymerization is performed at the following polymerization temperature.   The method for producing a π-conjugated copolymer according to claim 7, wherein the pyrrole compound is pyrrole.   The method for producing a π-conjugated copolymer according to claim 7, wherein the thiophene compound is 3,4-ethylenedioxythiophene.   The method for producing a π-conjugated copolymer according to claim 7, wherein the oxidizing agent contains an iron salt or a persulfate.   The method for producing a π-conjugated copolymer according to claim 7, wherein a mixed solvent of isopropanol and water is used as a polymerization solvent.   The method for producing a π-conjugated copolymer according to claim 7, wherein the polymerization temperature is 30 ° C or lower.   A structure, wherein the surface of an oxide film obtained by electrolytic oxidation of a valve action metal is coated with the π-conjugated copolymer according to any one of claims 1 to 6. The structure according to claim 13 , wherein the valve metal includes at least one selected from aluminum, silicon, tantalum, niobium, titanium, and zirconium.   A solid electrolytic capacitor comprising the π-conjugated copolymer according to claim 1 as a solid electrolyte. In the method of manufacturing a solid electrolytic capacitor in which a solid electrolyte layer made of a π-conjugated polymer is provided on a porous dielectric metal film having a valve action, on the dielectric film,
General formula (III)

(Wherein R ^{1 to} R ³ represent the same meaning as in claim 1),
Formula (IV)

(Wherein R ⁴ and R ⁵ represent the same meaning as in claim 1), a single solution of an oxidizing agent having a polymerization initiating ability or the oxidizing agent and 2-anthraquinone sulfonate anion . A solid electrolytic capacitor comprising a step of forming a π-conjugated copolymer according to any one of claims 1 to 6 on the dielectric film by polymerization using a mixed electrolyte solution Method. The manufacturing method of the solid electrolytic capacitor of Claim 16 superposed | polymerized in the temperature range of -30 degreeC-40 degreeC. The method for producing a solid electrolytic capacitor according to claim 16 , wherein the polymerization is performed in an atmosphere having a relative humidity of 5% to 70%. The method for producing a solid electrolytic capacitor according to claim 16 , wherein the porous metal having a valve action includes at least one selected from aluminum, silicon, tantalum, niobium, titanium, and zirconium. R ¹ , R ² , R ⁴ and R ⁵ are each independently a hydrogen atom, a linear or branched saturated or unsaturated alkyl group having 1 to 10 carbon atoms, or a linear chain having 1 to 10 carbon atoms. Monovalent group selected from the group consisting of linear or branched saturated or unsaturated alkoxy groups, linear or branched saturated or unsaturated alkyl ester groups having 1 to 10 carbon atoms, halogen atoms and cyano groups Or R ¹ and R ² and R ⁴ and R ⁵ are each bonded at an arbitrary position to form a cyclic structure of a 3- to 7-membered saturated or unsaturated hydrocarbon, and the cyclic structure is ether and The method for producing a solid electrolytic capacitor according to claim 16 , which represents one that may optionally contain a sulfonyl bond, and R ³ represents a hydrogen atom. The method for producing a solid electrolytic capacitor according to claim 16 , wherein the pyrrole compound is pyrrole and the thiophene compound is 3,4-ethylenedioxythiophene. The method for producing a solid electrolytic capacitor according to claim 16 , wherein the oxidizing agent having a polymerization initiating ability contains an iron salt or a persulfate. The method for producing a solid electrolytic capacitor according to claim 16 , comprising a step of polymerizing a plurality of times. The method for producing a solid electrolytic capacitor according to claim 16 , wherein the maximum thickness of the solid electrolyte layer formed on the dielectric film is 10 μm to 200 μm.

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