JP2014070066A - Electron-conductive oligomer, method for manufacturing the same, coating material including the electron-conductive oligomer, antistatic coated object, electronic member, and electron-conductive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron-conductive oligomer exhibiting, in cases of applications thereof as coat films and antistatic coated objects, an excellent adhesiveness with a coating target substrate and forming a film of a smooth quality by virtue of the low crystallinity thereof without entailing film cracks, light scatters, etc.SOLUTION: The electron-conductive oligomer of the present invention is provided by doping, with an acid including anions possessing fluoro groups and sulfonyl groups or a salt thereof, an oligothiophene derivative which is a molecule formed as a result of the bonding of 6 or more thiophene derivatives having substituents at 3- or 4-positions thereof.

Description

  The present invention generally relates to an electron conductive oligomer, and more specifically, when applied as a coating film and an antistatic coating, the film has excellent adhesion to a coating substrate and forms a smooth film quality. The present invention relates to an electron conductive oligomer that is improved so as not to cause cracking or light scattering, and a method for producing the same. The present invention also relates to a paint, an antistatic coating, and an electronic member containing such an electron conductive oligomer. The present invention further relates to an electron conductive composition in which such an electron conductive oligomer is dispersed.

  In recent years, it has become important to impart antistatic properties to resins. To achieve this, antistatic agents such as surfactants have been conventionally applied to the surface of resin molded products, or antistatic properties have been achieved. A method of kneading an agent into a resin is known. However, in the former method, the antistatic property is remarkably lowered after a long time, so that it is difficult to put it into practical use as a highly antistatic resin having durability. On the other hand, in the latter method, the compatibility between the antistatic agent and the resin is poor, and the antistatic agent is peeled off from the surface of the molded product, or bleeding or blooming occurs.

  Antistatic agents such as surfactants are dependent on humidity, and at low humidity, the antistatic effect is deactivated, or after molding the resin, the antistatic effect is at least 1 to It took 3 days and there was a problem that it was slow-acting.

  In addition, a method of kneading carbon black or carbon fiber into a resin has been proposed. According to this method, a resin composition having excellent antistatic properties and durability in antistatic properties can be obtained. However, this method has problems such as the kneaded material being peeled off, a transparent molded product not being obtained, and the selection of the color of the molded product being restricted.

  As a method for solving the above problems, the present inventors have prepared a solution in which a metal salt composed of a cation that is an alkali metal or an alkaline earth metal is dissolved in a polyamide resin, a polyetheresteramide resin, an aliphatic polyester, An antistatic composition obtained by adding to a polylactic acid resin, a thermoplastic elastomer and rubber has been proposed (see, for example, Patent Document 1).

  In addition, as a method for producing salt-modified electrostatic dissipative polymers made of polyurethane, there is a method in which lithium bis (fluoroalkylsulfonyl) imide is dissolved in a co-solvent and added. It has been proposed (see Patent Document 2).

  As the conductive polymer, polyaniline-based, polypyrrole-based, and polythiophene-based conductive polymers are well known. In particular, conductive poly (3,4-ethylenedioxythiophene) (PEDOT) has excellent transparency. And it has already been commercialized as a PEDOT colloid aqueous solution (trade name Pylon P, manufactured by Bayer), and is widely used in the field of electronic components as a conductive coating agent.

  Also proposed is a method of forming a porous material on the surface of an electrode substrate by electrolytic polymerization of 3,4-ethylene dioxythiophene (EDOT) in a solution containing bis (perfluoroalkanesulfonyl) imide or a salt thereof. (See Patent Document 3).

  There has also been proposed a method for producing PEDOT-PSS by subjecting EDOT to chemical oxidative polymerization using persulfate in an aqueous medium in the presence of polystyrene sulfonic acid (PSS) (see Patent Document 4).

International Publication WO 01/79354 A1 (Claims) US Pat. No. 6,140,405 (Claim 1, 14 and 15) JP 2006-351289 A (Claims 1 and 5) Japanese Patent Laid-Open No. 7-90060

  However, in the method described in Patent Document 1, the antistatic performance may not be sufficient depending on the type of metal salt added to the antistatic composition. Further, when metal salts such as perchloric acid are used, when the metal is packaged using a film or sheet made of this antistatic composition, there is a problem that the metal surface is corroded, rusted or contaminated.

  Further, in the method described in Patent Document 2, an auxiliary solvent (ethylene carbonate, dimethyl sulfoxide, tetramethylene sulfone, N-methyl-2-pyrrolidone, etc.) for dissolving metal salts is used for the molded article of the antistatic composition. Bleeding or blooming on the surface contaminates the product. Further, the antistatic property is lowered by wiping the surface of the molded product, and the durability of the antistatic property is not sufficient. In particular, in a high temperature and high humidity atmosphere, bleeding and blooming are promoted.

  Moreover, although the said PEDOT-PSS which patent document 4 discloses shows the outstanding electroconductivity, there exists the following restrictions on the industrial application from the restrictions of the manufacturing conditions on the characteristic. That is, there are restrictions such as strong acidity, insufficient adhesion to the coated substrate, low moisture resistance and light resistance, low compatibility with general-purpose resins, and low solubility in water and organic solvents. . The electropolymerization method disclosed in Patent Document 3 also produces many by-products having different molecular weights, and there are restrictions on production conditions.

  The present invention has been made in view of the above problems, and when applied as a coating film and an antistatic coating, it has excellent adhesion to a coated substrate, forms a smooth film quality, and is free from cracks and light of the film. An object is to provide an electron conductive oligomer that does not cause scattering or the like.

  It is another object of the present invention to provide an electron conductive oligomer having both ion conduction type antistatic characteristics and electron conduction type antistatic characteristics.

  Another object of the present invention is to provide an electron conductive oligomer that forms a transparent film.

  Another object of the present invention is to provide an electron conductive oligomer having a narrow molecular weight distribution.

  Another object of the present invention is to provide a method for producing such an electron conductive oligomer.

  Still another object of the present invention is to provide a paint and an antistatic coating using such an electron conductive oligomer.

  Another object of the present invention is to have excellent thermal stability, no bleeding, blooming and migration contamination, no dependence on humidity, high immediate effect, no deterioration of physical properties, and excellent antistatic property. It is an object to provide an electron conductive composition having sustained properties.

  The electron conductive oligomer according to the present invention comprises an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded, an acid having an anion having a fluoro group and a sulfonyl group, or Doped with the salt.

  Ion conduction is an image in which ions move within and between molecules to hand baton, whereas electron conduction is an image in which electrons move within and between molecules as a ball rolls into a cylinder. The latter is faster in static electricity and more effective as an antistatic agent. The electron conductive oligomer according to the present invention has a property of electron conduction derived from an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded, and has a fluoro group and a sulfonyl group. It has been found that the effect as an antistatic agent is enhanced because it also has the characteristics of ionic conduction derived from an acid having an anion having a group or a salt thereof.

  The acid having an anion having the fluoro group and the sulfonyl group or a salt thereof is preferably doped in an amount of 1 mol or more, more preferably 2 mol or more, per molecule of the oligothiophene derivative. However, it is preferable to suppress it to less than 100 mol% with respect to the number of repeating units (number of moles) of one molecule of the oligothiophene derivative.

  It has been found that when six or more thiophene derivatives having a substituent at the 3-position or 4-position are linked, high conductivity is exhibited.

  As the oligothiophene derivative, a hexamer of 3,4-ethylenedioxythiophene is preferable. Oligo (3,4-ethylenedioxythiophene) generates a carrier that can move freely, and thus has an electron conductivity type conductivity while being an organic substance. This oligo (3,4-ethylenedioxythiophene) has excellent adhesion to the coated substrate, and since it is low crystalline, it forms a smooth film quality and does not cause cracking or light scattering of the film. A coating having

  As the oligothiophene derivative, a hexamer of 3-alkylthiophene can also be preferably used.

  The acid having an anion having a fluoro group and a sulfonyl group includes bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide or trifluoromethanesulfonic acid, and the salt having the fluoro group and the sulfonyl group is lithium bis (Fluorosulfonyl) imide, lithium bis (trifluoromethanesulfonyl) imide or lithium trifluoromethanesulfonate.

  The method for producing an electron conductive oligomer according to another aspect of the present invention includes a step of preparing an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded, and a medium Into the oligothiophene derivative, an acid having an anion having a fluoro group and a sulfonyl group or a salt thereof is added and stirred, and the acid having an anion having a fluoro group and a sulfonyl group or a salt thereof is doped. Obtaining a solution containing the prepared oligothiophene derivative.

  The medium includes a volatile solvent, a polymerizable monomer, an oligomer, and a prepolymer described later.

  An electron conductive composition according to still another aspect of the present invention provides an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded to each other, and a negative group having a fluoro group and a sulfonyl group. An electron conductive oligomer formed by doping with an acid having ions or a salt thereof (first salt) is included. The electron conductive oligomer is dispersed in a polymerizable monomer, oligomer or prepolymer in which a salt having an anion having a fluoro group and a sulfonyl group (second salt) is dissolved.

  The electron conductive oligomer is excellent in compatibility with a polymerizable monomer, oligomer or prepolymer in which a second salt having an anion having a fluoro group and a sulfonyl group is dissolved. The above-mentioned electron conductive polymer, which has both ionic conduction and electronic conduction characteristics and is highly effective as an antistatic agent, dissolves a salt (second salt) having an anion having a fluoro group and a sulfonyl group. Since it is dispersed in the polymerizable monomer, oligomer or prepolymer, it becomes an electron conductive composition having a high antistatic effect.

  In this specification, “dispersion” refers to a state in which electron-conducting oligomers are dispersed or dissolved in the form of fine droplets in the composition. The electron conductive oligomer is dispersed alone or dissolved in a volatile solvent.

  Volatile solvent means a solvent that vaporizes at room temperature. Water, methanol, ethanol, isopropanol, 1-butanol, 2-butanol, cyclohexanol and other alcohols, acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone A volatile solvent selected from the group consisting of ketones such as cyclohexanone, ethers such as tetrahydrofuran, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, and esters such as methyl acetate, ethyl acetate, and butyl acetate Can do. The reason why the volatile solvent is selected is to facilitate drying after the composition is applied to the object. As long as it has volatility, it is not limited to the above, and any can be used.

  The polymerizable monomer means a compound having a functional group to be polymerized, and examples thereof include a polymerizable monomer having an acryloyl group, a methacryloyl group, a vinyl group and the like. Examples of the mode include monomers, oligomers, and those having three or more active energy ray-curable functional groups in the molecule.

  Examples of the polymerizable monomer include monofunctional monomers: methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, phenoxyethyl (meth) ) Acrylate, 2-ethoxyethyl (meth) acrylate, 2-ethoxyethoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polycaprolactone-modified hydroxyethyl (meth) acrylate, Bifunctional compounds such as dicyclopentenyloxyethyl (meth) acrylate, N-vinylpyrrolidone, acryloylmorpholine, isobornyl (meth) acrylate, vinyl acetate, styrene, etc .: Neopentyl glycol di (meth) acrylate 1,9-nonanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) ) Acrylate, glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, propylene, etc., polyfunctional ones: trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane 3 Tri (meth) acrylate of propylene oxide adduct, tri (meth) acrylate of 6 mol ethylene oxide adduct of trimethylpropane, glycerin propoxytri (meth) acrylate, dipentane erythritol hexa (meth) acrylate, di Such as hexa (meth) acrylate of caprolactone adduct of pentaerythritol and the like.

  Furthermore, as the activated energy ray-curable (meth) acrylate-based compound, 2-vinyloxyethyl (meth) acrylate, 3-vinyloxypropyl (meth) acrylate, 1-methyl-2-vinyloxyethyl (meth) acrylate, (Meth) acrylic acid 2-vinyloxypropyl, (meth) acrylic acid 4-vinyloxybutyl, (meth) acrylic acid 4-vinyloxycyclohexyl, (meth) acrylic acid 5-vinyloxypentyl, (meth) acrylic acid 6-vinyl Roxycyclohexyl, 4-vinyloxymethylcyclohexyl (meth) acrylate, p-vinyloxymethylphenylmethyl (meth) acrylate, 2- (vinyloxyethoxy) ethyl (meth) acrylate, 2- (meth) acrylic acid 2- ( Vinyloxyethoxyethoxy) ethyl, 2- (vinyloxyethoxyethoxyethoxy) ethyl (meth) acrylate, etc. Can be mentioned.

  An oligomer refers to a polymer having a relatively low molecular weight to which a finite number of monomers (generally up to 100) are bonded. A polymer means a state in which a very large number (several hundreds or more) of monomers are bonded to an oligomer. Examples of the oligomer include unsaturated polyester, polyester (meth) acrylate, polyether (meth) acrylate, acrylic (meth) acrylate, urethane (meth) acrylate, and epoxy (meth) acrylate. Among these, polyethylene glycol mono- or di (meth) acrylate is preferably used. Among them, polyethylene glycol mono- or di (meth) acrylate having at least 6 oxyethylene units is preferably used.

  A prepolymer is an intermediate product that stops the polymerization or condensation reaction of the monomer at an appropriate point. It is in the pre-stage of becoming a polymer, and it can easily cause polymerization or crosslinking reaction by using a curing agent or the like. Includes urethane resin-based prepolymers and silicon resin-based prepolymers. Examples of the prepolymer having three or more functional groups include diisocyanate: hexamethylene diisocyanate, isophorone dicyanate, tolylene diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate dicyclohexylmethane diisocyanate, and 2,2,4-trimethylhexacene. Methylene diisocyanate, lysine diisocyanate, norbornane diisocyanate and the like, and hydroxyl group-containing (meth) acrylate: monofunctional ones such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, Examples include those obtained by reacting trifunctional or higher functional groups such as dipentaerythritol penta (meth) acrylate. It is.

The acid having the fluoro group and the sulfonyl group is preferably bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide or trifluoromethanesulfonic acid. The salt having a fluoro group and a sulfonyl group is lithium bis (fluorosulfonyl) imide ((FSO ₂ ) ₂ NLi), lithium bis (trifluoromethanesulfonyl) imide ((CF ₃ SO ₂ ) ₂ NLi) or trifluoromethanesulfonic acid. Lithium (CF ₃ SO ₃ Li) is preferred.

  The cations to be paired are preferably selected from cations of the group consisting of alkali metals, group 2A elements, transition metals and amphoteric metals in addition to lithium.

  0.005-50 with respect to 100 parts by mass of the polymerizable monomer, oligomer or prepolymer in which the salt (second salt) having an anion having the fluoro group and the sulfonyl group is dissolved in the electron conductive oligomer. It is preferable to contain 0.0 part by mass.

  In the polymerizable monomer, oligomer or prepolymer before dispersing the electron conductive oligomer, the salt having the anion having the fluoro group and the sulfonyl group (second salt) is the polymerizable monomer, oligomer, It is contained in an amount of 0.01 to 30 parts by mass with respect to 100 parts by mass of the composition containing the prepolymer, resin, elastomer or adhesive resin. This composition is an ion conductive composition.

The electron conductive oligomer is preferably dissolved in an ionic liquid and dispersed in the polymerizable monomer, oligomer or prepolymer. An ionic liquid can be used as a medium for dissolving the electron conductive polymer. An ionic liquid refers to a salt (en) present in the liquid. Basically, the ionic liquid is classified into three types: pyridine, alicyclic amine, and aliphatic amine. . As an ionic liquid with good dispersibility, bis (trifluoromethanesulfonylimide) methyltributylammonium salt ((CF ₃ SO ₂ ) ₂ N ⁻ .N ⁺ (CH ₃ ) (C ₄ H ₉ ) ₃ ) (third Salt).

  The electron conductive composition of the present invention further includes an antioxidant, a heat stabilizer, an ultraviolet absorber, a flame retardant, a flame retardant aid, a colorant, a pigment, an antibacterial / antifungal agent, a light resistant agent, a plasticizer, and an adhesive. Requires known additives such as imparting agent, dispersant, defoaming agent, curing catalyst, curing agent, leveling agent, water repellent, coupling agent, filler, vulcanizing agent, chelating agent, vulcanization accelerator Can be added accordingly.

  A film, a paint, an electronic member, etc. can be obtained using the electronic conductive composition of the present invention. Further, the antistatic composition of the present invention can be cured on the molding surface to form an antistatic coating. The composition of the present invention works particularly effectively when used as a film, paint or coating.

  Polymerization of the (meth) acryloyl group and alkenyl group for curing is performed by energy such as heating, ultraviolet light, visible light, and electron beam, and a known polymerization initiator may be used as appropriate.

  An oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded, contains an anion having a fluoro group and a sulfonyl group or a salt thereof as a dopant anion. Electron conductive oligomers, when applied as coatings and antistatic coatings, have excellent adhesion to the coated substrate and low crystallinity to form a smooth film quality, such as film cracking and light scattering In addition, since the flow of static electricity is fast, the effect as an antistatic agent is high, and it can be usefully applied to electronic device applications. Further, by dispersing this electron conductive polymer in a polymerizable monomer, oligomer or prepolymer in which a second salt having an anion having a fluoro group and a sulfonyl group is dissolved, a highly antistatic conductive property is obtained. A functional polymer composition was obtained.

The purpose of obtaining an electron conductive oligomer that has excellent adhesion to the coated substrate, forms a smooth film quality, and does not cause cracking or light scattering of the film, as shown in the following “Chemical Formula 1”. An oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 4-position are bonded, is doped with an acid having an anion having a fluoro group and a sulfonyl group or a salt thereof. Here, oligo 3,4-ethylenedioxythiophene hexamer is illustrated as an oligothiophene derivative, and lithium bis (trifluoromethanesulfonyl) imide ((CF ₃ SO ₂ ) ₂ NLi) is illustrated as a doping agent. To do.

An electron conductive oligomer composed of a hexamer of 3,4-ethylenedioxythiophene containing lithium bis (trifluoromethanesulfonyl) imide ((CF ₃ SO ₂ ) ₂ NLi) as a doping agent, It was found to have higher conductivity than that which was not included.

  In general, in a conductive polymer, electrons are delocalized along a conjugated system. This is usually through the overlap of π orbitals, and the π system is expanded to form a valence band. When electrons are removed from this π system (p doping) or given electrons (n doping), charged units called bipolarons are generated. As the bipolaron moves through the polymer chain, macroscopic conductivity develops.

According to the present invention, as shown in “Chemical Formula 1”, a dopant anion ((CF ₃ SO ₂ ) ₂ N ⁻ ) which is an anion of a super strong acid and has high nucleophilicity is an oligo 3,4-ethylenedioxy It strongly correlates with the thiophene hexamer, and generates polaron (radical cation) or bipolarone (dication) having cation radical property and stabilizes it. That is, the dopant anion (CF ₃ SO ₂ ) ₂ N ⁻ acts as a p-doping agent. On the other hand, Li ions, which are cations, are surrounded by ether oxygen and sulfur atoms to form a chelate compound and stabilize.

  When an electric field is applied to the electron conductive oligomer from the outside, Li ion species use the molecular motion of ether oxygen atoms and sulfur atoms in the cured film toward the corresponding pole (film surface). It moves (ion transport) and develops ion conduction type antistatic characteristics. That is, it is an image in which Li ions move within and between molecules so as to hand baton. On the other hand, an electron-conducting polymer having a cationic radical property exhibits an electron-conducting antistatic property. That is, it is an image in which radicals (electrons) move in and between molecules so as to roll the ball into the cylinder.

  The acid having an anion having a fluoro group and a sulfonyl group or a salt thereof is 1 mol or more, more preferably 2 mol or more, and the number of repeating units of one molecule of oligothiophene derivative (number of moles). ) Is preferably less than 100 mol%.

  For example, one molecule of the oligothiophene derivative shown in Chemical Formula 1 has 6 repeating units. When this oligothiophene derivative forms a polaron (radical cation), 1 mol of an acid having an anion having a fluoro group and a sulfonyl group or a salt thereof is required for one molecule of the oligothiophene derivative. When the amount is less than 1 mol, the resulting thin film contributes little to the conductivity. In the case of forming a bipolaron (dication) as shown in Chemical Formula 1, the contribution to the conductivity of the thin film is greater than in the case of forming a polaron. When forming this bipolaron, the acid or its salt which has an anion provided with a fluoro group and a sulfonyl group is required 2 mol with respect to 1 molecule of oligothiophene derivatives. On the other hand, when the number of repeating units (number of moles) of one molecule of the oligothiophene derivative is 100 mol% or more, that is, in the case of Chemical Formula 1, if 6 mol or more is doped, electrons cannot move. Therefore, it is preferable to suppress the dope amount of the acid having an anion having a fluoro group and a sulfonyl group or a salt thereof to less than 100 mol% with respect to the number (mol number) of repeating units of one molecule of the oligothiophene derivative. .

  As described above, the electron conductive oligomer obtained in the present invention has both an ion conduction type antistatic property and an electron conduction type antistatic property. It becomes a polymer. This electron conductive oligomer is also characterized by high transparency. The concepts of “ion conduction type” and “electron conduction type” are described in detail in Shigeji Konagaya, Kagaku to Kogyo, 75 (10), p. 483 to 493 (2001). The synthesis of thiophene oligomers is described in detail in “Creation / Functional Development / Application of Electron Conjugated Organic Materials” (CMC Publishing Co., Ltd., issued on January 16, 2008) supervised by Teijiro Hatakeyama.

  In addition, by dispersing this electron conductive oligomer in a polymerizable monomer, oligomer or prepolymer in which a salt having an anion having a fluoro group and a sulfonyl group is dissolved, bleeding, blooming and migration of the antistatic agent are performed. A conductive polymer composition free of contamination is provided.

Examples of the present invention will be described below. In the sentence, an index may be displayed. For example, “1.5E + 02” means 1.5 × 10 ² .

  (Synthesis of oligo 3,4-ethylenedioxythiophene)

[Method by Tamao-Kumada coupling reaction]
“Chemical Formula 2” shows the overall synthesis reaction formula of oligo 3,4-ethylenedioxythiophene.

  As shown in the formula (1), 2,5-dibromo-3,4-ethylenedioxythiophene was synthesized from 3,4-ethylenedioxythiophene (EDOT). Next, as shown in the formula (2), using 1 mol of EDOT Grignard reagent and 1 mol of 2,5-dibromothiophene, Tamao-Kumada coupling reaction (aromatic Grignard reagent and aromatic halide and By applying a nickel or palladium catalyst to form a carbon-carbon bond) (Tetrahedron, 1982, 38, 3347) and applying a trimer of 3,4-ethylenedioxythiophene (3EDOT) 0.34 mol was synthesized. Then, as shown in Formula (3), 3EDOT was brominated, and 0.24 mol of 2-bromo-3,4-ethylenedioxythiophene trimer (2-Br-3EDOT) was synthesized. Next, as shown in Formula (4), using the Grignard reagent of 2-bromo-3,4-ethylenedioxythiophene trimer (2-Br-3EDOT) and 2-Br-3EDOT, Tamao -A hexamer of 3,4-ethylenedioxythiophene (EDOT) was synthesized by applying the Kumada coupling reaction. By this method, an oligo 3,4-ethylenedioxythiophene hexamer, which is an electron conductive oligomer having a narrow molecular weight distribution, could be synthesized.

  [Method by Suzuki-Miyaura coupling reaction]

The hexamer of 3,4-ethylenedioxythiophene (EDOT) is produced by the Suzuki-Miyaura coupling reaction shown in the following “Chemical Formula 3” (organoboron compound and halogenated by the action of nucleophilic species such as palladium catalyst and base). (Chemical reaction of cross-coupling with aryl) (J. Org. Chem., 2004, 69, 4821).

  That is, as shown in Formula (1), 2-bromo-3,4-ethylenedioxythiophenethiophene was synthesized from 3,4-ethylenedioxythiophene (EDOT). Next, this 2-bromo-3,4-ethylenedioxythiophenethiophene is reacted with a Grindard reagent of EDOT consisting of 1 mol of EDOT as shown in the formula (2) to give 2 of 3,4-ethylenedioxythiophene. A mer (2EDOT) was synthesized. Thereafter, as shown in Formula (3), 2EDOT was brominated to synthesize a dibromo form of 3,4-ethylenedioxythiophene dimer. Next, as shown in Formula (4), a 2EDOT pinacol boric acid derivative was synthesized, and then, as shown in Formula (5), 2EDOT pinacol boric acid derivative and 3,4-ethylenedioxythiophene 2 amount The dibromo form of the product was cross-coupled by a Suzuki-Miyaura coupling reaction to synthesize a hexamer of 3,4-ethylenedioxythiophene (EDOT) (oligo 3,4-ethylenedioxythiophene).

  (Preparation of methyl ethyl ketone solution of bis (fluorosulfonyl) imide-doped oligo 3,4-ethylenedioxythiophene hexamer)

In 100 ml of methyl ethyl ketone (MEK), 0.005 mol (4.21 parts by mass) of oligo 3,4-ethylenedioxythiophene hexamer (6EDOT) and bis (fluorosulfonyl) imide ((FSO ₂ ) ₂ NH) 0 0.011 mol (1.98 parts by mass) was added and stirred at 20 ° C. for 4 hours, followed by filtration with glass fiber filter paper to obtain a MEK liquid composition. Further, elemental analysis showed that the doping rate of bis (fluorosulfonyl) imide was about 33 mol%.

  (Synthesis of electron conductive composition)

  In the MEK composition, 5 parts by mass of an acrylic resin (MP-1600, manufactured by Soken Chemical Co., Ltd.) is dissolved as a binder resin, and an electron conductive oligo 3,4-ethylenedioxythiophene hexamer composition is dissolved. Obtained.

  (Formation of antistatic coating)

  The electron conductive oligo 3,4-ethylenedioxythiophene hexamer composition was added to a bar coater no. 4 was applied to a transparent polyethylene terephthalate film (PET) (thickness 38 μm) and dried at 100 ° C. for 3 minutes to obtain a conductive resin film (calculated coating film thickness 0.5 μm). The surface resistivity of the film was 1.5E + 02Ω / sq. The film was held at 105 ° C. for 500 hours to conduct a heat resistance test. The surface resistivity after the heat resistance test was 4.3E + 02Ω / sq.

  (Synthesis of oligo 3-hexylthiophene hexamer)

  Applying Tamao-Kumada coupling reaction with 1.0 mol of 2-bromo-3-hexylthiophene and 1.0 mol of 5-bromo-3-hexylthiophene to obtain bithiophene, The terminal C—H bond was halogenated and the cross-coupling reaction was performed again to expand the thiophene unit to obtain 0.09 mol of oligo 3-hexylthiophene hexamer (3HEXT).

  (Preparation of acrylate solution of lithium bis (trifluoromethanesulfonyl) imide-doped oligo 3-hexylthiophene hexamer)

  Pentaerythritol triacrylate solution (trade name: Sanconol PETA, manufactured by Sanko Chemical Co., Ltd.) in which 0.005 mol of oligo 3-hexylthiophene hexamer (6HEXT) is dissolved in 20 parts by mass of lithium bis (trifluoromethanesulfonyl) imide -20R) After adding to 20 parts by mass and stirring at 20 ° C. for 6 hours, the mixture was filtered through a glass fiber filter paper to obtain a conductive acrylate composition.

  (Formation of antistatic coating)

  As a photoinitiator, 0.6 parts by mass of Irgacure 907 (manufactured by Ciba Geigy Co., Ltd.) was added to the conductive acrylate composition to prepare a liquid composition. This composition was applied to the surface of a prism acrylic resin (pitch 50.0 μm, apex angle 88 °) placed on the surface of a base film (made of PET, thickness 250 μm), and then in the air using a high-pressure mercury lamp. Were irradiated with ultraviolet rays to obtain a transparent prism plate having a hardness of 2H and a thickness of 1.0 μm. The surface resistivity of this prism plate was 6.0E + 03Ω / sq. Then, after standing for 1 hour under conditions of 70% humidity and 80 ° C., the surface resistivity was measured and found to be 7.0E + 03Ω / sq.

  The MEK solution of the electron conductive oligomer 6EDOT obtained in Example 1 and the acrylic resin of the binder was applied on a stainless steel plate having a thickness of 1 mm, and then dried at 50 ° C. under reduced pressure. This is punched into two circular shapes and set facing each other as an electrode. A nylon non-woven fabric impregnated with an electrolytic solution [0.5M lithium bis (trifluoromethanesulfonyl) imide aqueous solution] is sandwiched between them as a separator. It was caulked with a coin-shaped case to make an electrochemical capacitor. The discharge capacity of constant current discharge (100 μA) of this capacitor was 0.1F. The internal resistance of the constant resistance discharge curve was 50Ω.

To 100 parts by mass of MEK solution of bis (fluorosulfonyl) imide-doped oligo 3,4-ethylenedioxythiophene hexamer prepared by the same method as in Example 1, 50 parts by mass of 2-hydroxyethylacrylamide and bis (trifluoromethane) 3 parts by mass of sulfonylimide) methyltributylammonium salt was added and stirred, and then MEK was removed under reduced pressure to obtain an electron conductive oligomer composition. This electron conductive oligomer composition was applied to a polyethylene terephthalate film (Toyobo Co., Ltd., A4300, thickness 38 μm) by a micro gravure coating method (thickness 1.5 μm). Next, using a high-pressure mercury lamp (80 W), ultraviolet rays were irradiated (200 mJ / cm ² ) in the air, and the film was crosslinked to obtain a film coated with a conductive polymer. The surface resistivity of this coating film was 7.3E + 03Ω / sq.

  In the same manner as in Example 1, 0.02 mol (3.1 parts by mass) of lithium trifluorosulfonate was used instead of bis (fluorosulfonyl) imide, and lithium trifluorosulfonate-doped oligo 3,4- An MEK solution composition of ethylenedioxythiophene hexamer was prepared. Further, an electroconductive oligo 3,4-ethylenedioxythiophene hexamer composition containing 5 parts by mass of a polyester resin (STAFIX, manufactured by Fuji Film Co., Ltd.) as a binder resin and containing a polyester binder resin. I got a thing. This composition was dropped on a glass plate and dried at 50 ° C. for 1 hour to obtain a 0.7 μm thick film. The conductivity of this film, measured using a 4-probe conductivity meter (MCP-600, manufactured by Mitsubishi Chemical Corporation), was 5 S / cm. The electrical conductivity after standing for 240 hours under the conditions of 85 ° C. and 85% relative humidity was 4 S / cm. The film made of the present conductive polymer composition showed utility as an antistatic agent excellent in wet heat resistance and as a cathode material for a solid electrolytic capacitor.

As the salt having an anion having a fluoro group and the sulfonyl group used in the present invention, in addition to those described above, for _{example, LiN (C 2 F 5 SO} 2) 2, LiN (C 4 F 9 SO 2 ) (CF ₃ SO ₂ ), LiN (C ₈ F ₁₇ SO ₂ ) (CF ₃ SO ₂ ), LiN (CF ₃ CH ₂ OSO ₂ ) ₂ , LiN (CF ₃ CF ₂ CH ₂ OSO ₂ ) ₂ , LiN ( HCF ₂ CF ₂ CH ₂ OSO ₂ ) ₂ , LiN ((CF ₃ ) ₂ CHOSO ₂ ) ₂ , tris (fluoroalkylsulfonyl) methidolithium Li (CF ₃ SO ₂ ) ₃ C, and the like can also be used.

  In the above examples, 3,4-ethylenedioxythiophene hexamer and 3-hexylthiophene hexamer are exemplified, but the present invention is not limited to this, Tamao-Kumada coupling reaction and By appropriately combining the Suzuki-Miyaura coupling reaction, many oligothiophene derivatives such as 9-mer, 12-mer and 15-mer can be produced.

  It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  When applied as a coating film or antistatic coating, the electron conductive oligomer according to the present invention has excellent adhesion to the coated substrate and low crystallinity, thereby forming a smooth film quality and cracking of the film. And no light scattering. This electronic conductive polymer is used for antistatic and conductive coatings, capacitors, touch screens, organic LEDs, transparent conductive ink jet printing inks, semiconductor packaging materials by coating and printing on films, liquid crystal protective films, touch panels, It can be used in a wide range of electronic member applications such as organic EL, organic TFT, organic semiconductor, dye-sensitized solar cell, conductive polymer electrode, solid electrolytic capacitor, conductive organic thin film, and electronic device.

Claims (12)

  Electronic conductivity obtained by doping an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3- or 4-position are bonded, with an anion having a fluoro group and a sulfonyl group or a salt thereof. Oligomer.   The electron-conducting oligomer according to claim 1, wherein the oligothiophene derivative includes a hexamer of 3,4-ethylenedioxythiophene or a hexamer of 3-alkylthiophene.   The acid having an anion having the fluoro group and the sulfonyl group or the salt thereof is 1 mol or more with respect to one molecule of the oligothiophene derivative, and the number of repeating units (mole number) of one molecule of the oligothiophene derivative. The electron conductive oligomer according to claim 1 or 2, wherein the electron conductive oligomer is doped less than 100 mol%. The acid having an anion having a fluoro group and a sulfonyl group includes bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) imide or trifluoromethanesulfonic acid,
The electron conduction according to any one of claims 1 to 3, wherein the salt having a fluoro group and a sulfonyl group includes lithium bis (fluorosulfonyl) imide, lithium bis (trifluoromethanesulfonyl) imide, or lithium trifluoromethanesulfonate. Oligomers. Preparing an oligothiophene derivative which is a molecule in which 6 or more thiophene derivatives having a substituent at the 3-position or 4-position are bonded;
In the medium, the oligothiophene derivative and an acid having an anion having a fluoro group and a sulfonyl group or a salt thereof are added and stirred, and the acid having an anion having a fluoro group and a sulfonyl group or a salt thereof is doped. And a step of obtaining a solution containing the prepared oligothiophene derivative. Doping an oligothiophene derivative, which is a molecule in which six or more thiophene derivatives having a substituent at the 3- or 4-position are bonded, with an anion having a fluoro group and a sulfonyl group or a salt thereof (first salt) An electronically conductive oligomer comprising
An electron conductive composition in which the electron conductive oligomer is dispersed in a polymerizable monomer, oligomer or prepolymer in which a salt having an anion having a fluoro group and a sulfonyl group (second salt) is dissolved.   0.005-50 with respect to 100 mass parts of the polymerizable monomers, oligomers or prepolymers in which the electron conductive oligomer is dissolved in the salt having the anion having the fluoro group and the sulfonyl group (second salt). The electron conductive composition according to claim 6, comprising 0.0 part by mass.   The electron conductive composition according to claim 6 or 7, wherein the electron conductive oligomer is dissolved in an ionic liquid and dispersed in the polymerizable monomer, oligomer or prepolymer.   The electron conductive composition according to claim 8, wherein the ionic liquid contains bis (trifluoromethanesulfonylimide) methyltributylammonium salt (third salt).   The coating material containing the electron conductive oligomer of any one of Claims 1-4.   The antistatic coating containing the electron conductive oligomer of any one of Claims 1-4.   The electronic member containing the electron conductive oligomer of any one of Claims 1-4.