JP3453191B2 - Method for producing conductive organic polymer and method for producing solid electrolytic capacitor using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a conductive organic polymer and a method for producing a solid electrolytic capacitor using the same.

[0002]

2. Description of the Related Art Generally, an organic polymer called conductive polyaniline has the general formula (II)

[0003]

[Chemical 3]

(In the formula, m and n represent the mole fractions of the quinonediimine structural unit and the phenylenediamine structural unit in the repeating unit, respectively, 0 <m <1, 0 <n <1, m
+ N = 1. ), A quinonediimine-phenylenediamine type polyaniline having a quinonediimine structural unit and a phenylenediamine structural unit represented by the formula (1) as main repeating units is doped with a protonic acid, and generally, the quinonediimine structural unit in such polyaniline is It is said that the protonation of nitrogen in the nitrogen is essential for developing conductivity.

A film or film made of such a conductive polyaniline is prepared by dissolving quinonediimine / phenylenediamine type polyaniline in a suitable solvent and casting it as described in JP-A-3-28229. It can be obtained by drying, forming a film, immersing it in a protonic acid aqueous solution, and performing doping treatment (protonic acid doping).

However, after preparing a solvent-soluble quinonediimine / phenylenediamine type polyaniline film and doping it with a protonic acid, it usually takes a considerably long time. That is, the dope time varies depending on the type of protonic acid used, physical properties such as the film thickness and porosity of the polyaniline film, but for example, in the case of a polyaniline film of about 20 μm, 1 S / cm
In order to have the above electric conductivity, it is necessary to immerse it in an aqueous polyvinyl sulfonic acid solution for several hours. Further, when a protic acid aqueous solution such as 1,5-naphthalenedisulfonic acid is used, it may take a longer time.

On the other hand, in JP-A-60-133027 and Faraday Discuss. Chem. Soc., 88, 317 (1989), general formula (I)

[0008]

[Chemical 4]

An imino-p-phenylene type polyaniline powder having an imino-p-phenylene structural unit represented by the following as a main repeating unit is used as a solution of ferric chloride in acetonitrile or hydrogen peroxide and hydrochloric acid, sulfuric acid or phosphoric acid. It is shown that the imino-p-phenylene type polyaniline is oxidized to be converted into a quinone diimine / phenylenediamine type polyaniline, and at the same time, a protonic acid is doped by immersing it in an aqueous solution mixed with an inorganic acid solution such as ing. This doping method is
Since it involves an oxidative reaction, it is usually called oxidative doping in distinction from the above-mentioned protonic acid doping.

The present inventors have already used, for example, about 20 μm of an imino-p-phenylene type polyaniline film, a quinone-based oxidizing agent or hydrogen peroxide as an oxidizing agent, and various organic acids as a protonic acid. As a result of research on the oxidative doving treatment, it has been found that the oxidative doving treatment is significantly faster than the protic acid doving treatment (JP-A-5-232995 and JP-A-5-242530).

Although the oxidative doving treatment is more practical than the proton acid doving treatment, for example, an imino-p-phenylene type polyaniline film of about 20 μm is used, and p-benzoquinone is used as an oxidizing agent. In the case of oxidative doving using polyvinyl sulfonic acid as a protonic acid, treatment for 10 minutes
Only a conductivity of about 1 S / cm can be obtained. Furthermore, 1
To obtain a conductivity of about 0 S / cm, it is necessary to perform the treatment for 60 minutes by the same method. On the other hand, in the case of oxidative doving using hydrogen peroxide as an oxidant and polyvinyl sulfonic acid as a protonic acid, a treatment for 10 minutes
Although a conductivity of about 20 S / cm can be obtained, however, the obtained film is greatly damaged by the oxidizing agent, and the strength of the film is significantly reduced.

Generally, the oxidizing agent used for such oxidative dobbing is not particularly limited as long as it has an oxidizing power capable of oxidizing the imino-p-phenylene type polyaniline.
However, the conductivity stability of the obtained film depends on the kind of the protonic acid that has been dubbed, and what kind of protonic acid is dubbed greatly affects the conductivity stability of the obtained polyaniline. In general, organic protic acids provide more stable polyaniline than inorganic protic acids.

For example, when ferric chloride is used as an oxidizing agent, anions (chlorine ions) are produced after the oxidation reaction according to the following formula. FeCl ₃ + e ⁻ → FeCl ₂ + Cl ^{− In} this way, the chlorine ions generated after the oxidation reaction dope polyaniline as a dopant. In general,
Anions generated from such an oxidant are chlorine ions, nitrate ions, inorganic ions such as sulfate ions,
There is a problem that the obtained polyaniline is inferior in stability.

On the other hand, the electrolytic capacitor is a capacitor in which an insulating coating is formed on the surface of a metal foil of aluminum or tantalum by electrolytic oxidation treatment and the insulating coating is used as a dielectric. Recent major technical requirements for such an electrolytic capacitor include miniaturization, low impedance accompanying high frequency of a circuit, high reliability, long life, and cost reduction. In order to meet these demands, research has been carried out in the direction of solidifying an electrolyte of a conventional electrolytic capacitor, and as such a solid electrolyte, for example, polypyrrole, polythiophene, polyfuran, polyaniline, etc.,
Various conductive polymers have been proposed.

More specifically, for example, JP-A-63-17
3313 discloses that a dielectric oxide film is formed on a film-forming metal, polypyrrole is deposited on the dielectric oxide film by chemical oxidative polymerization of pyrrole, and this is used as a conductive layer. Is electrolytically polymerized, and a conductive polymer composed of the polypyrrole is laminated as a solid electrolyte. In addition, JP-A-1-253
Similarly, Japanese Patent No. 226 discloses that a conductive layer made of manganese dioxide is formed on a dielectric film, and polypyrrole or polythiophene is laminated thereon by electrolytic polymerization to obtain a solid electrolyte.

However, in all of these methods, it is necessary to laminate polypyrrole or the like on the dielectric film which is not an electric conductor by electrolytic reaction, which is a problem. That is, a chemical oxidation polymerization film layer or a manganese dioxide layer must be provided on the dielectric film as a conductive layer to serve as an electrode for electrolytic polymerization, and electrolytic polymerization can be performed only in this way.

On the other hand, in Japanese Patent Laid-Open No. 3-35516,
A method has been proposed in which polyaniline in a solution state is applied on a dielectric film to form a film, and then the polyaniline film is immersed in a solution of a protonic acid to perform a doping treatment. According to this method, a conductive polyaniline film can be formed on the dielectric film by a simple means without providing an electrode, which is advantageous in terms of manufacturing efficiency and cost. However, as described above, both the method of doping the polyaniline film with a protonic acid and the oxidative doping using ferric chloride have the above-mentioned problems.

[0018]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional method for obtaining a conductive polyaniline, and has a doping rate, that is, a conductive It is an object of the present invention to provide a method by which a polyaniline can be preferentially doped by a protic acid contained in an oxidant solution, the expression of which is extremely rapid, and thus a conductive polyaniline having excellent stability can be obtained. To aim.

A further object of the present invention is to provide a method for manufacturing a solid electrolytic capacitor using such a method.

[0020]

The method for producing a conductive organic polymer according to the present invention is represented by the general formula (I).

[0021]

[Chemical 5]

An organic polymer composition prepared by dissolving an organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit in an organic solvent is coated on a substrate and dried, and then an organic acid is added. The method is characterized in that an oxidation treatment is carried out with a solution in which a ferric salt having an anion as a counter ion is dissolved.

Further, the method for producing a solid electrolytic capacitor according to the present invention is a solid having a dielectric oxide film formed on a film-forming metal and having a film made of a conductive organic polymer on the dielectric oxide film as a solid electrolyte. In the method of manufacturing an electrolytic capacitor, the general formula (I)

[0024]

[Chemical 6]

A solution prepared by dissolving an organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit in an organic solvent is applied on the dielectric oxide film and dried, and then an organic acid anion is obtained. It is characterized in that it is subjected to an oxidation treatment with a solution in which a ferric salt having as a counter ion is dissolved to impart conductivity to the organic polymer.

The polyaniline used in the present invention is an organic polymer which has an imino-p-phenylene structural unit represented by the general formula (I) as a main repeating unit and is soluble in an organic solvent in a dedoped state. According to the present invention, in consideration of the strength and the like of the obtained conductive polyaniline film, the imino-p-phenylene type polyaniline is
The intrinsic viscosity [η] measured at 30 ° C. in N-methyl-2-pyrrolidone is preferably 0.40 dl / g or more.

Such polyaniline is disclosed in JP-A-3-5.
As described in detail in Japanese Patent No. 2929, an organic polymer having a quinonediimine structural unit represented by the general formula (II) and a phenylenediamine structural unit as main repeating units, wherein the organic polymer is used in an undoped state in an organic solvent. It can be obtained by reducing a soluble organic polymer with a reducing agent.

Examples of the reducing agent include phenylhydrazine, hydrazine, hydrazine hydrate, hydrazine sulfate,
Hydrazine compounds such as hydrazine hydrochloride and reductive metal hydride compounds such as lithium aluminum hydride and lithium borohydride are preferably used. Hydrazine hydrate or phenylhydrazine is particularly preferably used as the reducing agent because it does not produce a residue after the reduction reaction.

In the method of the present invention, a solution is prepared by dissolving the polyaniline having the thus-obtained imino-p-phenylene structural unit as a main repeating unit in an appropriate organic solvent, and using this solution as a base material. A solution prepared by coating the above and drying it to form a film of polyaniline, and then dissolving a film of this polyaniline in which a ferric salt having an organic acid anion as a counter ion is dissolved (hereinafter sometimes referred to as a dope solution). .) To give conductivity to the polyaniline.

Such a dope solution is usually obtained by reacting ferric hydroxide with an excess of an organic acid, as described in, for example, JP-A-1-170616. Therefore, a ferric salt solution having such an organic acid anion as a counter ion usually contains an excess of organic acid. The ferric hydroxide can be obtained, for example, by neutralizing an aqueous solution of ferric chloride or ferric sulfate with an alkali and washing the obtained precipitate.

The organic acid used in the present invention is, for example,
Organic carboxylic acids or phenols, preferably having an acid dissociation constant pKa value of 4.8 or less. Such organic acids include mono- or polybasic acids such as aliphatic, aromatic, araliphatic and alicyclic. Such an organic acid may have a hydroxyl group, a halogen, a nitro group, a cyano group, an amino group or the like. Therefore, specific examples of such organic acid include, for example, acetic acid, n-butyric acid, pentadecafluorooctanoic acid, pentafluoroacetic acid, trifluoroacetic acid, trichloroacetic acid, dichloroacetic acid, monofluoroacetic acid, monobromoacetic acid, monochloroacetic acid, cyanoacetic acid. , Acetylacetic acid, nitroacetic acid, triphenylacetic acid, formic acid, oxalic acid, benzoic acid, m-bromobenzoic acid, p-chlorobenzoic acid, m-chlorobenzoic acid, p-chlorobenzoic acid, o
-Nitrobenzoic acid, 2,4-dinitrobenzoic acid, 3,5-dinitrobenzoic acid, picric acid, o-chlorobenzoic acid, p
-Nitrobenzoic acid, m-nitrobenzoic acid, trimethylbenzoic acid, p-cyanobenzoic acid, m-cyanobenzoic acid, thymol blue, salicylic acid, 5-aminosalicylic acid, o
-Methoxybenzoic acid, 1,6-dinitro-4-chlorophenol, 2,6-dinitrophenol, 2,4-dinitrophenol, p-oxybenzoic acid, bromophenol blue, mandelic acid, phthalic acid, isophthalic acid, malein Acid, fumaric acid, malonic acid, tartaric acid, citric acid, lactic acid, succinic acid, α-alanine, β-alanine, glycine, glycolic acid, thioglycolic acid, ethylenediamine-N, N '
-Diacetic acid, ethylenediamine-N, N, N ', N'-tetraacetic acid and the like can be mentioned.

Further, the organic acid may have a sulfonic acid or a sulfuric acid group. Examples of such an organic acid include, for example, aminonaphthol sulfonic acid, methanilic acid, sulfanilic acid, allyl sulfonic acid, lauryl sulfuric acid, xylene sulfonic acid, chlorobenzene sulfonic acid,
1-propanesulfonic acid, 1-butanesulfonic acid, 1-
Hexanesulfonic acid, 1-heptanesulfonic acid, 1-octanesulfonic acid, 1-nonanesulfonic acid, 1-decanesulfonic acid, 1-dodecanesulfonic acid, benzenesulfonic acid, styrenesulfonic acid, p-toluenesulfonic acid,
Naphthalenesulfonic acid, ethylbenzenesulfonic acid, propylbenzenesulfonic acid, butylbenzenesulfonic acid, pentylbenzenesulfonic acid, hexylbenzenesulfonic acid, heptylbenzenesulfonic acid, octylbenzenesulfonic acid, nonylbenzenesulfonic acid, decylbenzenesulfonic acid, undecyl Benzenesulfonic acid, dodecylbenzenesulfonic acid, pentadecylbenzenesulfonic acid, octadecylbenzenesulfonic acid, diethylbenzenesulfonic acid, dipropylbenzenesulfonic acid, dibutylbenzenesulfonic acid, methylnaphthalenesulfonic acid, ethylnaphthalenesulfonic acid, propylnaphthalenesulfonic acid, Butylnaphthalenesulfonic acid, Pentylnaphthalenesulfonic acid, Hexylnaphthalenesulfonic acid,
Heptylnaphthalenesulfonic acid, octylnaphthalenesulfonic acid, nonylnaphthalenesulfonic acid, decylnaphthalenesulfonic acid, undecylnaphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, pentadecylnaphthalenesulfonic acid, octadecylnaphthalenesulfonic acid, dimethylnaphthalenesulfonic acid, diethylnaphthalenesulfone Acid, dipropyl naphthalene sulfonic acid, dibutyl naphthalene sulfonic acid, dipentyl naphthalene sulfonic acid,
Dihexylnaphthalenesulfonic acid, diheptylnaphthalenesulfonic acid, dioctylnaphthalenesulfonic acid, dinonylnaphthalenesulfonic acid, trimethylnaphthalenesulfonic acid, triethylnaphthalenesulfonic acid, tripropylnaphthalenesulfonic acid, tributylnaphthalenesulfonic acid, camphorsulfonic acid, acrylamide- Examples thereof include t-butyl sulfonic acid.

Further, in the present invention, a polyfunctional organic sulfonic acid having two or more sulfonic acid groups in the molecule can also be used. Examples of such polyfunctional organic sulfonic acids include ethanedisulfonic acid, propanedisulfonic acid, butanedisulfonic acid, pentanedisulfonic acid, hexanedisulfonic acid, heptanedisulfonic acid, octanedisulfonic acid, nonanedisulfonic acid, decanedisulfonic acid, benzene. Disulfonic acid, naphthalene disulfonic acid,
Toluene disulfonic acid, ethylbenzene disulfonic acid,
Propylbenzenedisulfonic acid, butylbenzenedisulfonic acid, dimethylbenzenedisulfonic acid, diethylbenzenedisulfonic acid, dipropylbenzenedisulfonic acid,
Dibutylbenzenedisulfonic acid, methylnaphthalenedisulfonic acid, ethylnaphthalenedisulfonic acid, propylnaphthalenedisulfonic acid, butylnaphthalenedisulfonic acid, pentylnaphthalenedisulfonic acid, hexylnaphthalenedisulfonic acid, heptylnaphthalenedisulfonic acid,
Octyl naphthalene disulfonic acid, nonyl naphthalene disulfonic acid, dimethyl naphthalene disulfonic acid, diethyl naphthalene disulfonic acid, dipropyl naphthalene disulfonic acid, dibutyl naphthalene disulfonic acid, naphthalene trisulfonic acid, naphthalene tetrasulfonic acid, anthracene disulfonic acid, anthraquinone disulfonic acid,
Phenanthrene disulfonic acid, fluorenone disulfonic acid, carbazole disulfonic acid, diphenyl methane disulfonic acid, biphenyl disulfonic acid, terphenyl disulfonic acid, terphenyl trisulfonic acid, naphthalene sulfonic acid-formalin condensate, phenanthrene sulfonic acid-formalin condensate, Examples thereof include anthracene sulfonic acid-formalin condensate, fluorene sulfonic acid-formalin condensate, and carbazole sulfonic acid-formalin condensate. The position of the sulfonic acid group in the aromatic ring is arbitrary.

Further, in the present invention, the organic acid may be a polymeric acid. Examples of such a polymer acid include polyvinyl sulfonic acid, polyvinyl sulfuric acid, polystyrene sulfonic acid, sulfonated styrene-butadiene copolymer, polyallyl sulfonic acid, polymethallyl sulfonic acid, poly-2-acrylamido-2-methyl. Propane sulfonic acid, polyhalogenated acrylic acid, polyisoprene sulfonic acid, N-sulfoalkylated polyaniline, nuclear sulfonated polyaniline and the like can be mentioned. A fluorine-containing polymer known as Nafion (registered trademark of Du Pont, USA) is also suitably used as the polymer acid.

However, particularly in the present invention,
As the organic acid that gives polyaniline having stable conductivity, a polyvalent organic acid such as polyvinyl sulfonic acid, polyvinyl sulfuric acid, polyisoprene sulfonic acid, polystyrene sulfonic acid, ethanedisulfonic acid, or naphthalene disulfonic acid is preferably used. Further, aliphatic organic acids such as polyvinylsulfonic acid, polyvinylsulfuric acid, polyisoprenesulfonic acid, and ethanedisulfonic acid are faster than organic acids containing an aromatic ring and are preferably used. In particular, polyvinyl sulfonic acid is most preferably used because of its conductivity stability and high doping speed.

The concentration of such a dope solution is appropriately selected depending on the type of organic acid used, the treatment temperature, the film thickness of polyaniline, the electrical conductivity of the target conductive polyaniline, etc., but the concentration is usually 1 The range of ˜30 wt% is preferred.
The molar ratio of ferric ion to organic acid in the dope solution is not particularly limited as long as the doping proceeds, but it is usually 1 to 2 in terms of the equivalent ratio of organic acid / ferric ion.
The range is 00, and particularly preferably the range is 1 to 100.

The method for producing a conductive organic polymer according to the present invention can be advantageously used particularly for producing a solid electrolytic capacitor using such a conductive organic polymer. Specifically, a dielectric film is formed on the above-described film-forming metal, and then a solution of imino-p-phenylene type polyaniline dissolved in an organic solvent is applied on the dielectric film. The film is dried to form a film made of polyaniline, and then the polyaniline film is oxidized by the dope solution as described above to impart conductivity to the polyaniline, thus making the solid electrolyte of the electrolytic capacitor for a short time. Can be formed.

To form the dielectric coating on the film-forming metal, it is preferable to form the dielectric film by anodic oxidation on the film-forming metal that has been made porous to increase the surface area.
In order to form a film made of polyaniline on the dielectric film, in addition to the method of immersing the dielectric film in the above-mentioned polyaniline solution and drying, the above-mentioned polyaniline solution is applied onto the dielectric film and dried. Good. Further, the solution may be dropped on the dielectric film by a device such as a dispenser, or the solution may be impregnated under vacuum. Further, the drying method may be drying under normal pressure, drying under an inert gas under normal pressure, drying under low pressure at a low temperature, or heating under reduced pressure. Of course, as described above, various methods can be used without particular limitation. The drying temperature is usually in the range of 30 to 200 ° C, preferably 60 to 180 ° C, more preferably 80 to 160 ° C, and the time required is usually 10 minutes to 10 minutes. It is in the range of 3 hours, preferably 20 minutes to 2 hours, more preferably 30 minutes to 1
It is a range of time.

After such a doping process, the conductive polyaniline film is washed with an appropriate solvent such as ethanol or acetone and dried, and then a conductive material such as carbon or silver paste is formed on the conductive polyaniline film. The terminals are attached using a paste, then they are molded with an epoxy resin or the like, and preferably subjected to an aging treatment to obtain solid electrolytic capacitors.

In the present invention, as the film-forming metal,
Usually, aluminum or tantalum is preferably used,
Therefore, a film of aluminum oxide or tantalum oxide is usually preferably used as the dielectric film.

[0041]

As described above, according to the method of the present invention,
An organic polymer composition obtained by dissolving imino-p-phenylene type polyaniline having excellent solubility in an organic solvent is used.
An organic polymer having high conductivity in a short time by applying this on a base material, drying it, and oxidizing it with an oxidizing agent solution containing a ferric salt having an organic acid anion as a counter ion. Thus, a highly conductive polyaniline having excellent stability and durability can be obtained.

Further, by utilizing such a method for manufacturing a solid electrolytic capacitor, similarly, a highly conductive polyaniline having excellent stability and durability can be formed on a dielectric film in a short time. Therefore, a solid electrolytic capacitor can be advantageously manufactured.

[0043]

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

Reference Example 1 (Production of quinonediimine / phenylenediamine type conductive polyaniline in a doped state by oxidative polymerization of aniline)
In a 10-liter separable flask equipped with a stirrer, a thermometer and a straight pipe adapter, 6000 g of distilled water, 3
360 ml of 6% hydrochloric acid and 400 g (4.295 mol) of aniline were charged in this order to dissolve the aniline. Separately, while cooling with ice water, distilled water 149 in a beaker
Add 434 g (4.295 mol) of 97% concentrated sulfuric acid to 3 g,
A sulfuric acid aqueous solution was prepared by mixing. This sulfuric acid aqueous solution was added to the separable flask, and the entire flask was cooled to -4 ° C in a low temperature constant temperature bath. Next, in a beaker, 2293 g of distilled water was added with 980 ammonium peroxodisulfate.
g (4.295 mol) was added and dissolved to prepare an oxidizing agent aqueous solution.

The entire flask was cooled in a low temperature constant temperature bath, and while maintaining the temperature of the reaction mixture at -3 ° C or lower, while stirring, to an acidic aqueous solution of aniline salt, using a tubing pump, using a straight pipe adapter, the above peroxo tube was used. Aqueous ammonium disulfate solution was gradually added dropwise at a rate of 1 ml / min or less.
First, the colorless and transparent solution changed from green-blue to black-green as the polymerization proceeded, and then a black-green powder precipitated.

Although a temperature rise is observed in the reaction mixture during the precipitation of the powder, in order to obtain a high molecular weight polymer,
It is important to keep the temperature in the reaction system at 0 ° C or lower, preferably -3 ° C or lower. After the powder is deposited, the dropping rate of the aqueous ammonium peroxodisulfate solution may be slightly increased, for example, about 8 ml / min. However, also in this case, it is necessary to monitor the temperature of the reaction mixture and adjust the dropping rate so as to maintain the temperature at −3 ° C. or lower. Thus, after the dropping of the aqueous ammonium peroxodisulfate solution was completed over 7 hours, the stirring was continued for another 1 hour at a temperature of -3 ° C or lower.

The obtained polymer powder was filtered off, washed with water, washed with acetone, and vacuum dried at room temperature to obtain a black-green quinonediimine / phenylenediamine type conductive polyaniline powder 4
30 g was obtained. This was pressure-molded into a disk having a diameter of 13 mm and a thickness of 700 μm, and by the van der Pauw method,
The conductivity was measured and found to be 14 S / cm.

(Production of Quinonediimine / Phenylenediamine Type Solvent-Soluble Polyaniline by Dedoping of Conductive Organic Polymer) 350 g of the above-mentioned doped conductive polyaniline powder was added to 4 liters of 2N ammonia water, and the mixture was rotated by an auto-homomixer. 5 at several 5000 rpm
Stir for hours. The mixture changed from black green to blue purple.

The powder was filtered off with a Buchner funnel, washed repeatedly with distilled water while stirring in a beaker until the filtrate became neutral, and then washed with acetone until the filtrate became colorless. did. Then, the powder is vacuum dried at room temperature for 10 hours to obtain a dark brown dedoped solvent-soluble quinone diimine / phenylenediamine type polyaniline powder 2
80 g was obtained. This polyaniline was soluble in N-methyl-2-pyrrolidone and had a solubility of 8 g (7.4%) in 100 g of the solvent. Also, the intrinsic viscosity [η] measured at 30 ° C. using this as a solvent was 1.23.

Example 1 A 25% aqueous solution of sodium polyvinylsulfonate (Aldr
ich) was subjected to an ion exchange treatment with an ion exchange resin to prepare an acid-form aqueous solution, and this aqueous solution was concentrated and solidified by an evaporator. Separately, 14.7 g of ferric sulfate hydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved by heating in 490 g of distilled water to obtain a transparent reddish brown solution, on which 5N sodium hydroxide aqueous solution 31. When 5 g was added with stirring, a colloidal precipitate (iron hydroxide) was obtained. Centrifuge this (3
000 rpm x 2 minutes), discard the supernatant, then
Distilled water was added and stirred. This operation was repeated until the waste liquid became 1.9 liters.

22 g of the polyvinyl sulfonic acid was added to the iron hydroxide colloidal solution thus obtained. The solution generated heat and the colloid was dissolved to obtain a clear reddish brown solution. Distilled water was added to this to a total amount of 110 g to prepare an aqueous solution of ferric polyvinyl sulfonate (hereinafter, this solution may be referred to as a dope solution).

1.90 g of phenylhydrazine was dissolved in 90 g of N-methyl-2-pyrrolidone, and then Reference Example 1 was used.
10 g of the solvent-soluble quinonediimine / phenylenediamine type polyaniline obtained in (4) was dissolved with stirring. At this time, the solution changes color from dark blue to light black brown, and at the same time,
Generation of nitrogen gas was confirmed, which confirmed that polyaniline was converted from quinone diimine phenylenediamine type to imino-p-phenylene type. This solution was filtered under reduced pressure with a G2 glass filter.

The solvent-soluble imino-p-phenylene type polyaniline solution thus obtained was cast on a glass plate, squeezed with a glass rod, and then at 120 ° C. for 3 hours.
After drying for 0 minutes, imino-p-with a film thickness of 20 to 45 μm
A phenylene type polyaniline film was obtained. This film was dipped in the dope solution for a predetermined time and further dried at 60 ° C. for 10 minutes to obtain a conductive polyaniline film. Neither film was significantly damaged by the doping process. Table 1 shows the relationship between the time of immersion in the dope solution and the electric conductivity of the obtained film.

Comparative Example 1 Polyaniline film before treatment with the dope solution obtained in Example 1 was treated with 10% by weight of polyvinyl sulfonic acid and 2.5.
After dipping at room temperature for a predetermined time in a mixed solvent system solution of ethanol / water (weight ratio 1: 1) in which wt% p-benzoquinone is dissolved, it is washed with ethanol and further at 60 ° C. for 10 hours.
After drying for a minute, a conductive polyaniline film was obtained.
Neither film was significantly damaged by the doping process. Table 1 shows the relationship between the time of immersion in the dope solution and the electrical conductivity of the obtained film.

Comparative Example 2 The polyaniline film obtained in Example 1 before treatment with the dope solution was immersed in an aqueous solution containing 10% by weight of polyvinylsulfonic acid and 7.5% by weight of hydrogen peroxide at room temperature for a predetermined time. After soaking, wash with ethanol and then at 60 ° C for 10
After drying for a minute, a conductive polyaniline film was obtained.
The obtained film had cracks, and the film treated for 30 minutes or more became shabby and was not suitable for the measurement of electric conductivity. Table 1 shows the relationship between the time of immersion in the dope solution and the electric conductivity of the obtained film.

[0056]

[Table 1]

Comparative Example 3 The polyaniline film before treatment with the dope solution obtained in Example 1 was immersed in a 10% by weight aqueous solution of polyvinyl sulfonic acid at room temperature for a predetermined time, washed with ethanol, and further 60 It was dried at 0 ° C. for 10 minutes to obtain a conductive polyaniline film. The conductivity of the obtained film is
When the immersion time is 30 minutes, it is 0.29 S / cm, which is 1
When it was 50 minutes, it was 1.3 S / cm.

Example 2 As a film forming metal, a porous sintered body having a volume of 20.8 mm ³ obtained by sintering fine powder of tantalum was used, and 0.1% by weight at 85 ° C.
A direct current voltage of 30 V was applied in a phosphoric acid aqueous solution to form an insulating film (dielectric film) made of tantalum oxide on the surface of the porous body, and used as a capacitor anode body.

The capacitor anode body was immersed in the polyaniline solution obtained in Example 1 and dried at 120 ° C. for 30 minutes to form a polyaniline film on the anode body. The capacitor anode body obtained by laminating the polyaniline film thus obtained was added to the dope solution prepared in Example 1 at room temperature.
After soaking for 80 minutes, wash with ethanol and then at 60 ° C for 2
It was dried for 0 minutes. After this, apply a conductive paste,
A cathode lead was attached. The solid electrolytic capacitor thus obtained had a capacitance of 92.9 μF at 120 Hz and a tangent of loss angle (tan δ) of 5.8%. The equivalent series resistance (ESR) at 1 MHz was 260 mΩ.

Example 3 A new dope solution was prepared by mixing 10 g of the dope solution obtained in Example 1 with 10 g of a 20 wt% aqueous solution of polyvinyl sulfonic acid. The polyaniline film before treatment with the dope solution obtained in Example 1 was dipped in the dope solution at room temperature for a predetermined time, washed with ethanol, and then 6
It was dried at 0 ° C. for 10 minutes to obtain a conductive polyaniline film. Table 2 shows the relationship between the time of immersion in the dope solution and the electrical conductivity of the obtained film.

Example 4 A new dope solution was prepared by mixing 10 g of the dope solution obtained in Example 1 with 20 g of a 20 wt% aqueous solution of polyvinyl sulfonic acid. The polyaniline film before treatment with the dope solution obtained in Example 1 was dipped in the dope solution at room temperature for a predetermined time, washed with ethanol, and then 6
It was dried at 0 ° C. for 10 minutes to obtain a conductive polyaniline film. Table 2 shows the relationship between the time of immersion in the dope solution and the electrical conductivity of the obtained film.

[0062]

[Table 2]

Example 5 Using the same dope solution as in Example 1, room temperature, 45 ° C. or 6
Treated at 0 ° C. The electric conductivity of the obtained film is shown in Table 3.

[0064]

[Table 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A 61-204266 (JP, A) JP-A 64-11159 (JP, A) JP-A 5-247204 (JP, A) JP-A 6- 45195 (JP, A) JP 7-29778 (JP, A) JP 7-82375 (JP, A) JP 7-97444 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 79/00-79/08 C08G 73/00-73/16

Claims (2)

(57) [Claims] 1. A compound represented by the general formula (I): The organic polymer composition obtained by dissolving an organic polymer having an imino-p-phenylene structural unit represented by the following as a main repeating unit in an organic solvent is applied on a substrate and dried, and then an organic acid anion is added thereto. A method for producing a conductive organic polymer, which comprises subjecting a solution of a ferric salt as an ion to a oxidization treatment. 2. A method for producing a solid electrolytic capacitor, comprising a dielectric oxide film formed on a film-forming metal, and having a film of a conductive organic polymer on the dielectric oxide film as a solid electrolyte. ) [Chemical 2] A solution prepared by dissolving an organic polymer having an imino-p-phenylene structural unit as a main repeating unit in an organic solvent is applied on the dielectric oxide film and dried, and then an organic acid anion is used as a counter ion. A method for producing a solid electrolytic capacitor, characterized in that the solid electrolytic capacitor is subjected to oxidation treatment with a solution in which a ferric salt is dissolved.