JP5740925B2 - Conductive coating composition and laminate - Google Patents

Description

  The present invention relates to a conductive coating composition capable of forming a conductive film, an antistatic film, and the like, and a laminate formed using the same.

  If dust adheres to the surface of an optical film of a display such as a liquid crystal display due to static electricity, the visibility of the display is lowered. As a technique for preventing this, it is known to provide an antistatic film on the optical film surface.

  As a conductive material to be blended in such an antistatic film, inorganic fine particles exhibiting conductivity such as antimony-doped tin oxide (ATO) and tin-doped indium oxide (ITO) have been conventionally used. Such inorganic fine particles have the advantage of being excellent in transparency and film strength.

  However, the antistatic film containing inorganic fine particles is usually formed by sputtering, vacuum deposition or the like, and there is a disadvantage that expensive equipment and a high temperature setting of, for example, 500 to 600 ° C. are required for the formation process. there were.

  In addition, when an antistatic film containing inorganic fine particles is formed on a glass substrate, the reflectance increases, resulting in a problem that the difference in refractive index from the glass increases and the visibility of the display decreases. Furthermore, since indium is a rare metal, its supply source is limited, and there are fluctuations in the supply amount, it is desirable to avoid use.

  It has been proposed to use a conductive organic polymer material such as polythiophene for the antistatic film of a liquid crystal display as a conductive material in place of the above-mentioned inorganic fine particles (see, for example, Patent Documents 1 and 2). In addition, for example, for the purpose of improving adhesion to a substrate and film hardness, it has also been proposed to form an antistatic film using a combination of a conductive organic polymer material and various alkoxysilanes (for example, Patent Documents). 3, 4, and 5).

  According to the organic conductive material, since the antistatic film can be formed by a general coating means without using sputtering or vacuum deposition, there is an advantage that the film can be formed by a simple and low-temperature process. Moreover, the resulting antistatic film has the advantages of high conductivity and permeability and excellent adhesion to the substrate.

  However, conventionally known organic antistatic films have the disadvantage that the film hardness is not sufficient and the surface is easily scratched. Furthermore, there was a problem that the chemical resistance was not sufficient. For example, when it is used as an antistatic film in a liquid crystal display, it is necessary to perform washing with an organic solvent such as acetone or alkali washing after forming the antistatic film and before setting a polarizing plate on the surface. Therefore, the antistatic film is easily changed by these washings, and improvement is demanded.

JP-A-10-96953 JP 2004-246080 A JP 2005-82768 A JP 2006-294532 A Special table 2010-528123

  In view of the present situation, the present invention can form an antistatic film having high hardness and high chemical resistance in addition to high conductivity and permeability and excellent adhesion to a substrate. It is an object of the present invention to provide a conductive coating composition that can be formed.

  As a result of intensive studies by the present inventors, it was found that the above-mentioned problems can be solved by using a conductive polymer in the form of particles having a small particle size and using this in combination with a specific hydrolyzable silane compound. The invention has been completed.

  That is, the present invention relates to a conductive coating composition comprising conductive polymer particles having a particle size (D50) of 200 nm or less and a binder component containing an alkoxysilane oligomer represented by the following general formula.

In the formula, R ₁ and R ₂ are the same or different and each represents an alkyl group having 1 to 4 carbon atoms. R ₃ and R ₄ are the same or different and represent H (hydrogen atom), a hydroxyl group, or an alkoxy group having 1 to 4 carbon atoms. However, at least one of the plurality of R ₃ and R ₄ is an alkoxy group. n represents an integer of 2 to 20.

  Further, the present invention provides a laminate including a base material and a conductive film provided on the base material, wherein the conductive film is formed from the conductive coating composition. Also related.

  According to the conductive coating composition of the present invention, an antistatic film can be formed by applying to a substrate at a low temperature by a general coating method, and the process from application to film formation can be simplified and simplified. It can be implemented at low cost.

  The conductive film obtained from the conductive coating composition of the present invention has high conductivity (that is, low surface resistivity of 1.0E + 10Ω / □ or less), high permeability, and excellent adhesion to a substrate. ing. Furthermore, the pencil hardness is B or higher and the film hardness is high.

  When the conductive coating composition of the present invention is applied to a glass substrate, the pencil hardness is H or higher and the film hardness is further increased, and excellent chemical resistance (organic solvent resistance, alkali resistance) is exhibited. be able to. In addition, the formed conductive film has extremely high transparency. Furthermore, since the difference in refractive index with glass is small, an effect of making it difficult to see defects (holes or dimples) on the glass surface can be expected.

Schematic diagram showing the laminated structure of general liquid crystal display measures

  Details of the present invention will be described below.

  The conductive coating composition of the present invention contains conductive polymer particles and a binder component.

(Conductive polymer particles)
The conductive polymer used in the present invention is a polymer material exhibiting conductivity. Specific examples include π-conjugated conductive polymers such as polythiophene, polyaniline, polypyrrole, polyparaphenylene, polyparaphenylene vinylene, and derivatives thereof.
Among these, a polythiophene conductive polymer composed of a composite of polythiophene and a dopant is preferably used from the viewpoints of high conductivity and chemical stability. More specifically, the polythiophene conductive polymer is a composite composed of poly (3,4-disubstituted thiophene) and a dopant.

The poly (3,4-disubstituted thiophene) constituting the polythiophene conductive polymer has the following formula (1):

It is preferable that it is a polythiophene of the cationic form which consists of a repeating structural unit shown by these. The cationic polythiophene refers to a polythiophene that is partly in a cationic form by extracting electrons from a part of the polythiophene in order to form a complex with a polyanion that is a dopant. .

In formula (1), R ₄ and R ₅ each independently represent a hydrogen atom or a C _1-4 alkyl group, or R ₄ and R ₅ are bonded to form a cyclic structure. A substituted or unsubstituted _C1-4 alkylene group is represented. Examples of the C _1-4 alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group. Examples of the substituted or unsubstituted C _1-4 alkylene group in which R ₄ and R ₅ are bonded to form a cyclic structure include, for example, a methylene group, 1,2-ethylene group, 1,3-propylene group, 1 , 4-butylene group, 1-methyl-1,2-ethylene group, 1-ethyl-1,2-ethylene group, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, etc. Is mentioned. Examples of the substituent that the C _1-4 alkylene group may have include a halogen group and a phenyl group. Suitable C _1-4 alkylene groups include methylene, 1,2-ethylene, and 1,3-propylene, with 1,2-ethylene being particularly preferred. Poly (3,4-ethylenedioxythiophene) is particularly preferable as the polythiophene having the above alkylene group.

  The dopant constituting the polythiophene-based conductive polymer is an anionic polymer that forms a complex by forming an ion pair with the polythiophene described above, and can stably disperse the polythiophene in water, that is, a polyanion. It is preferable. Examples of such dopants include carboxylic acid polymers (eg, polyacrylic acid, polymaleic acid, polymethacrylic acid, etc.), sulfonic acid polymers (eg, polystyrene sulfonic acid, polyvinyl sulfonic acid, etc.), and the like. These carboxylic acid polymers and sulfonic acid polymers may be copolymers of vinyl carboxylic acids and vinyl sulfonic acids with other polymerizable monomers (eg, acrylates, styrene, etc.). Of these, polystyrene sulfonic acid is particularly preferable.

  The polystyrene sulfonic acid preferably has a weight average molecular weight of more than 20000 and 500,000 or less. More preferably, it is 40000-200000. If polystyrene sulfonic acid having a molecular weight outside this range is used, the dispersion stability of the polythiophene conductive polymer in water may be lowered. The weight average molecular weight of the polymer is a value measured by gel permeation chromatography (GPC). For the measurement, an ultrahydrogel 500 column manufactured by Waters is used.

  The polythiophene conductive polymer can be obtained by oxidative polymerization in water using an oxidizing agent. In the oxidative polymerization, two kinds of oxidizing agents (first oxidizing agent and second oxidizing agent) are used. Suitable first oxidizing agents include, for example, peroxodisulfuric acid, sodium peroxodisulfate, potassium peroxodisulfate, ammonium peroxodisulfate, hydrogen peroxide, potassium permanganate, potassium dichromate, alkali perborate, copper Examples include salts. Of these primary oxidants, sodium peroxodisulfate, potassium peroxodisulfate, ammonium peroxodisulfate, and peroxodisulfate are most preferred. The amount of the first oxidizing agent used is preferably 1.5 to 3.0 mol equivalent, more preferably 2.0 to 2.6 mol equivalent, relative to the thiophene monomer used.

  As a suitable second dioxide agent, it is preferable to add a metal ion (for example, iron, cobalt, nickel, molybdenum, vanadium ion) in a catalytic amount. Of these, iron ions are the most effective. The amount of metal ion added is preferably 0.005 to 0.1 mol equivalent, more preferably 0.01 to 0.05 mol equivalent, relative to the thiophene monomer used.

  In this oxidative polymerization, water is used as a reaction solvent. In addition to water, alcohols such as methanol, ethanol, 2-propanol, and 1-propanol, and water-soluble solvents such as acetone and acetonitrile can be added.

  An aqueous dispersion of a conductive polymer is obtained by the above oxidative polymerization. The conductive coating composition of the present invention contains a particulate conductive polymer. Such conductive polymer particles may be conductive polymer particles contained in an aqueous dispersion of a conductive polymer. The aqueous dispersion can be produced by the oxidation polymerization described above. Moreover, the conductive polymer particle contained in the organic solvent (especially alcohol, such as ethanol) dispersion may be sufficient. Such an organic solvent dispersion of a conductive polymer can be produced, for example, according to the method described in Japanese Patent No. 4163867.

  The particle size of the conductive polymer particles used in the present invention is essential to be 200 nm or less. By using particles having a small particle diameter of 200 nm or less, the denseness of the conductive film formed by combining the conductive polymer and the alkoxysilane oligomer is improved, and the film hardness is improved. Specifically, since the conductive polymer particles can enter the dense structure formed by the alkoxysilane oligomer with good dispersibility, the film hardness can be improved and high conductivity can be exhibited. For the same reason, when the conductive coating composition of the present invention is applied on a glass substrate, the film hardness is further increased to H or higher, and the chemical resistance (organic solvent resistance, Alkali resistance) is improved. In the case of using particles having a particle size exceeding 200 nm, in addition to low conductivity, improvement in film hardness and chemical resistance cannot be achieved. Since the degree of improvement in the above effect increases as the particle size decreases, the particle size of the conductive polymer particles is preferably 60 nm or less, and more preferably 30 nm or less. Although the minimum of a particle size is not specifically limited, For example, it is 1 nm or more, Preferably it is 3 nm or more. More preferably, it is 5 nm or more, or 10 nm or more. In the present invention, the particle size of the conductive polymer particles is calculated as a particle size having an integrated value of 50% in the integrated distribution by measuring the number-based integrated (cumulative) distribution of the conductive particles.

  The particle diameter of the conductive polymer particles can be easily adjusted by appropriately selecting the dispersion conditions when producing the above-described conductive polymer dispersion (for example, paragraph of Japanese Patent No. 3966252). [0042]). Specifically, a dispersion stirrer such as a homogenizer can be used. (For example, see paragraph [0019] of JP 2010-24304 A).

(Binder component)
The conductive coating composition of the present invention contains a binder component together with conductive polymer particles. The binder component is a component necessary for the conductive coating composition to form a film on the substrate. In the present invention, the binder component may be composed of only one type, or two or more types may be used in combination. However, in the present invention, it is essential to contain at least an alkoxysilane oligomer as a binder component.

  The total amount of the binder component is preferably 150 to 10,000 parts by weight with respect to 100 parts by weight of the conductive polymer particles. When it is 150 parts by weight or more, the use ratio of the binder component becomes sufficient, and good hardness and chemical resistance can be obtained with the formed conductive film. When the amount is 10,000 parts by weight or less, a sufficient amount of the conductive polymer is contained, so that a conductive film having high conductivity and good chemical resistance can be formed. More preferably, it is 300 to 7000 parts by weight.

(Alkoxysilane oligomer)
The coating composition of the present invention includes an alkoxysilane oligomer. Since the alkoxysilane oligomer forms a dense structure in the coating film, it is considered that a conductive film having high hardness can be obtained in the present invention. Furthermore, since the conductive polymer particles having a small particle diameter enter the dense structure with good dispersibility, a conductive film having excellent hardness and chemical resistance and high conductivity can be obtained.

  An alkoxysilane oligomer is a high molecular weight alkoxysilane formed by condensation of monomers of alkoxysilane, and is an oligomer having one or more siloxane bonds (Si—O—Si) bonds in one molecule. That means. The weight average molecular weight is not particularly limited, but is preferably larger than 152 and not larger than 4000. More preferably, about 500-1500 is preferable. The weight average molecular weight of the oligomer is a value measured by gel permeation chromatography (GPC). For the measurement, an ultrahydrogel 500 column manufactured by Waters is used.

  The alkoxysilane oligomer used in the present invention is represented by the following general formula. As is apparent from the formula, the alkoxysilane oligomer of the present invention is a conventionally used alkoxysilane monomer (compound containing one silicon atom per molecule), an alkoxysilane compound having an epoxy group, polyether or polyester. It is a compound different from the alkoxysilane compound modified by the like.

In the formula, R ₁ and R ₂ are the same or different and each represents an alkyl group having 1 to 4 carbon atoms. R ₃ and R ₄ are the same or different and represent H (hydrogen atom), a hydroxyl group, or an alkoxy group having 1 to 4 carbon atoms. However, at least one of the plurality of R ₃ and R ₄ is an alkoxy group. n represents an integer of 2 to 20, more preferably an integer of 2 to 14. Examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl and the like. Examples of the alkoxy group having 1 to 4 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, t-butoxy and the like. The alkoxysilane oligomer used in the present invention may be composed of only one type of compound represented by the following general formula, or may be a mixture of multiple types.

  In the present invention, by using an alkoxysilane oligomer having a siloxane bond in the molecule in advance as a binder component, the conductive film is more dense than an alkoxysilane monomer or epoxysilane having no siloxane bond. As a result, it is presumed that the excellent effect of the present invention can be achieved. This effect becomes more prominent as the film forming temperature becomes lower. In addition, when an alkoxysilane polymer (with a condensation number n larger than that of an alkoxysilane oligomer) is used as a binder component, the steric repulsion increases, and the reactivity becomes poor and it is difficult to form a dense structure. As a result, it is estimated that the film hardness becomes weak. This tendency becomes more prominent as the molecular weight increases.

  It is preferable that the compounding quantity of the alkoxysilane oligomer with respect to all the binder components contained in an electroconductive coating composition is 97 to 100 weight%. When it is 97% by weight or more, the denseness of the film due to the incorporation of the alkoxysilane oligomer reaches a sufficient level, and it becomes possible to form a conductive film exhibiting high film hardness and excellent chemical resistance. More preferably, it is 98.5 weight% or more.

(Binder components other than alkoxysilane oligomers)
As described above, the conductive coating composition of the present invention may contain a binder component other than the alkoxysilane oligomer. Other binder components are not limited as long as they contain the alkoxysilane oligomer described above. Specifically, silane couplings such as 3-glycidoxypropyltrimethoxysilane, polyether-modified polydimethylsiloxane, and polyether-modified siloxane An agent can be used as a binder component. Resin binders can also be used, specifically, homopolymers such as polyester, polyacrylate, polymethacrylate, polyurethane, polyvinyl acetate, polyvinylidene chloride, polyamide, polyimide; styrene, vinylidene chloride, vinyl chloride, Examples thereof include copolymers obtained by copolymerizing monomers such as alkyl acrylate and alkyl methacrylate. These binders may be used independently and may use 2 or more types together.

(Solvent or dispersion medium)
The conductive coating composition of the present invention may be composed of only conductive polymer particles and an alkoxysilane oligomer, but it is usually preferable to further contain a solvent and / or a dispersion medium in order to facilitate handling. . The solvent or dispersion medium is not particularly limited as long as it can dissolve or disperse the conductive polymer and the alkoxysilane oligomer. When the conductive coating composition is aqueous, water and a mixed solvent of water and a solvent miscible with water can be used. The solvent miscible with water is not particularly limited. For example, alcohols such as methanol, ethanol, 2-propanol and 1-propanol, glycols such as ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, ethylene glycol diethyl ether and diethylene glycol dimethyl ether Ethers, glycol ether acetates such as ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycols such as propylene glycol, dipropylene glycol, tripropylene glycol, propylene glycol monomethyl ether, propylene glycol Monoethyl ether , Propylene glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, propylene glycol diethyl ether, dipropylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl Examples include ether acetate, propylene glycol ether acetates such as dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dimethylacetamide, acetone, acetonitrile, and mixtures thereof. When the conductive coating composition is an organic solvent-based solvent, the solvents listed above as solvents miscible with water and toluene, xylene, benzene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, diethyl ether, diisopropyl ether, methyl- t-Butyl ether, hexane, heptane and the like can be used. Of the above solvents or dispersion media, methanol, ethanol, and 2-propanol are particularly preferable. In addition, when each component of the composition for conductive coating is completely dissolved, it is referred to as a “solvent”, and when any component is dispersed without being dissolved, it is referred to as a “dispersion medium”.

  The solid content concentration of the conductive coating composition is not particularly limited as long as it is a uniform aqueous dispersion, but is preferably about 0.01 to 50% by weight at the time of coating. More preferably, it is 1 to 20% by weight. Application | coating can be easily implemented in this range. However, the concentration may be higher when the coating composition is sold or transported. In that case, a solvent and / or a dispersion medium may be added and diluted as appropriate at the time of use.

(Conductivity improver)
In order to further improve the conductivity, the coating composition of the present invention may further contain a conductivity improver. It does not specifically limit as said electroconductivity improver, According to the objective, it can select suitably. Specific examples include dimethyl sulfoxide, N-methylpyrrolidone, N-methylformamide, N-dimethylformamide, isophorone, propylene carbonate, cyclohexanone, γ-butyrolactone, and diethylene glycol monoethyl ether. Among these, N-methyl Formamide and N-methylpyrrolidone are preferred. These may be used individually by 1 type and may use 2 or more types together. The content of the conductivity improver in the conductive coating composition is not particularly limited, but is preferably about 430 to 13000 parts by weight and more preferably about 430 to 4330 parts by weight with respect to 100 parts by weight of the conductive polymer particles.

(Optional component)
In the conductive coating composition of the present invention, a surfactant (surface conditioner), an antifoaming agent, a rheology control agent, an adhesion imparting agent, an antioxidant, an acidic catalyst, particles and the like may be added as appropriate. Is possible.

  The surfactant is not particularly limited as long as it can improve leveling properties and obtain a uniform coating film. Examples of such surfactants include the following compounds: polyether-modified polydimethylsiloxane, polyether-modified siloxane, polyetherester-modified hydroxyl group-containing polydimethylsiloxane, polyether-modified acrylic group-containing polydimethylsiloxane, polyester-modified acrylic. Group-containing polydimethylsiloxane, perfluoropolydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, siloxane compounds such as perfluoropolyester-modified polydimethylsiloxane; fluorine-containing perfluoroalkylcarboxylic acid, perfluoroalkylpolyoxyethyleneethanol, etc. Organic compounds; Polyethers such as polyoxyethylene alkylphenyl ether, propylene oxide polymer, ethylene oxide polymer Compound; Carboxylic acid such as coconut oil fatty acid amine salt, gum rosin; Ester compound such as castor oil sulfate, phosphate ester, alkyl ether sulfate, sorbitan fatty acid ester, sulfonate ester, phosphate ester, succinate ester; Sulfonate compounds such as alkylaryl sulfonic acid amine salts and dioctyl sodium sulfosuccinate; Phosphate compounds such as sodium lauryl phosphate; Amide compounds such as coconut oil fatty acid ethanolamide; and acrylic copolymers . Among these, siloxane compounds and fluorine-containing compounds are preferable from the viewpoint of leveling properties, and polyether-modified polydimethylsiloxane is particularly preferable.

  A thickener may be added for the purpose of improving the viscosity. Examples of such thickeners include alginic acid derivatives, xanthan gum derivatives, water-soluble polymers such as saccharide compounds such as carrageenan and cellulose.

  The antioxidant is not particularly limited, and examples thereof include reducing or non-reducing water-soluble antioxidants. Examples of the water-soluble antioxidant having reducibility include substitution with two hydroxyl groups such as L-ascorbic acid, sodium L-ascorbate, potassium L-ascorbate, erythorbic acid, sodium erythorbate, and potassium erythorbate. Compounds having a lactone ring; monosaccharides and disaccharides such as maltose, lactose, cellobiose, xylose, arabinose, glucose, fructose, galactose, mannose; flavonoids such as catechin, rutin, myricetin, quercetin, kaempferol; curcumin, rosmarinic acid , Compounds having two or more phenolic hydroxyl groups such as chlorogenic acid, hydroquinone, 3,4,5-trihydroxybenzoic acid; cysteine, glutathione, pentaerythritol tetrakis (3-mer) Putobuchireto) include compounds having a thiol group such as. Non-reducing water-soluble antioxidants include, for example, oxidative degradation such as phenylimidazolesulfonic acid, phenyltriazolesulfonic acid, 2-hydroxypyrimidine, phenyl salicylate, sodium 2-hydroxy-4-methoxybenzophenone-5-sulfonate. The compound which absorbs the ultraviolet-ray which causes this is mentioned. These may be used alone or in combination of two or more.

  In addition, the conductive coating composition of the present invention may contain particles that impart scratch resistance and slidability. Examples of particles include inorganic particles. Examples of inorganic particles include silica, aluminum oxide, zinc oxide, potassium oxide, calcium oxide, chromium oxide, strontium oxide, tungsten oxide, magnesium oxide, titanium oxide, bismuth oxide, cerium oxide, and oxide. Metal oxides such as cobalt, iron oxide, fornium oxide, manganese oxide, tin oxide, yttrium oxide, zirconium oxide, antimony oxide, calcium carbonate, magnesium carbonate, barium carbonate, calcium silicate, calcium titanate, calcium sulfate, barium sulfate, etc. One or more compounds such as molybdenum sulfide, antimony sulfide, tungsten sulfide, boron nitride, nickel iodide, and their hydrates, kaolin, clay, talc, mica, bentonite, hydrotalcite, zeolite, pie Fillite, carbon black, and natural or synthetic mineral particles, such as graphite.

(Manufacturing method of coating composition)
Although the method for producing the conductive coating composition of the present invention is not particularly limited, the above compositions are mixed while stirring with a stirrer such as a mechanical stirrer or a magnetic stirrer, and stirred and mixed for about 1 to 60 minutes. Good. Specifically, first, a conductive polymer dispersion may be produced so that the conductive polymer particles have a predetermined particle size, and then each component may be mixed and stirred.

(Laminate)
The conductive coating composition of the present invention can form a conductive coating film by applying to a substrate to be coated and then drying. The material constituting the substrate to be coated on which the conductive coating composition is applied is not particularly limited. For example, polyethylene, polypropylene, ethylene / vinyl acetate copolymer, ethylene / acrylic acid ester copolymer, ionomer copolymer Polymer, polyolefin resin such as cycloolefin resin, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyoxyethylene, modified polyphenylene, polyphenylene sulfide and other polyester resins, nylon 6, nylon 6,6, nylon 9, semi-aromatic polyamide 6T6 Polyamide resins such as semi-aromatic polyamide 6T66 and semi-aromatic polyamide 9T, other acrylic resins, polystyrene, acrylonitrile styrene, acrylonitrile butadiene styrene, vinyl chloride resin Organic material such as; may be mentioned inorganic materials such as glass. In particular, when the conductive coating composition of the present invention is applied to a glass substrate, the film hardness becomes extremely high as H or more in pencil hardness and exhibits excellent chemical resistance (organic solvent resistance, alkali resistance). Is particularly preferable.

There is no restriction | limiting in particular as an application | coating method of an electroconductive coating composition, It can select suitably from well-known methods. Examples thereof include spin coating, gravure coating, bar coating, dip coating, curtain coating, die coating, and spray coating. In addition, printing methods such as screen printing, spray printing, ink jet printing, relief printing, intaglio printing, and lithographic printing can also be applied.
For drying the coating film of the conductive coating composition, a normal ventilation dryer, a hot air dryer, an infrared dryer or the like is used. Of these, drying and heating can be performed simultaneously by using a dryer having a heating means (hot air dryer, infrared dryer, etc.). As the heating means, in addition to the dryer, a heating / pressurizing roll having a heating function, a press machine, or the like can be used.

Although the drying conditions of a coating film are not specifically limited, For example, it is about 10 second-about 2 hours at 25 to 200 degreeC, Preferably, it is about 5 to 30 minutes at 80 to 150 degreeC. The dry film thickness of the coating film formed from the conductive coating composition of the present invention can be appropriately selected depending on the purpose. However, 25-380 nm is preferable for improving conductivity, hardness, and chemical resistance. More preferably, it is 30-350 nm.
By applying and drying the conductive coating composition on the substrate surface, a laminate including the conductive film formed on the substrate surface can be produced. As described later, the laminate can be applied to various uses, but in particular, when the substrate is a glass substrate, it can be suitably used as a laminate contained in a liquid crystal display device.

  FIG. 1 is a schematic diagram showing a laminated structure of a general liquid crystal display device. Reference numeral 1 denotes a color filter in the liquid crystal display device, and a glass substrate 2 is laminated on the surface of the color filter 1. Furthermore, the antistatic film (conductive film) 3 and the polarizing plate 4 are laminated in this order. The laminate of the present invention may be composed of only the glass substrate 2 and the antistatic film 3 or may be included in the above-described laminated structure of the liquid crystal display device. Further, it may be included in a laminate composed of the color filter 1, the glass substrate 2, and the antistatic film 3 before the liquid crystal display device is completed.

  Currently, three types of driving methods for liquid crystal display devices are widely used: a TN (twisted nematic) method, a VA (vertical alignment) method, and a horizontal electric field driving method. The laminate of the present invention can be applied to any type of liquid crystal display layer. In particular, in the horizontal electric field drive method, it is essential to provide an antistatic film in order to improve liquid crystal driveability in addition to prevention of dust adhesion, but the laminate of the present invention is also suitable for this horizontal electric field drive type liquid crystal display device. Can be applied to. In this case, the antistatic film achieves an effect of improving liquid crystal disturbance due to static electricity, and also has an effect of improving the visibility of the display due to high transparency and a difference in refractive index from glass.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Hereinafter, “parts” means “parts by weight” unless otherwise specified.

  The particle size (D50) was calculated as a particle size with an integrated value of 50% in each integrated distribution by measuring the number-based integrated (cumulative) distribution for each aqueous dispersion. Specifically, using a sample prepared by diluting each aqueous dispersion with pure water to prepare a 0.1% aqueous solution, using a particle size distribution analyzer ZETASIZER Nano-ZS manufactured by Sysmex Corporation, particle size measurement by zeta potential Went.

Example 1
100 parts of an aqueous dispersion Baytron PH500 (manufactured by HC Starck) containing a conductive polymer (poly3,4 ethylenedioxythiophene / polystyrenesulfonic acid) having a particle size (D50) of 20 nm 1.1 parts of conductive polymer and 98.9 parts of ion-exchanged water (when the conductive polymer is 100 parts, ion-exchanged water is 8991 parts), alkoxysilane oligomer MS-51 as a binder (Mitsubishi Chemical) 24 parts (2165 parts when the conductive polymer is 100 parts), 19 parts of N-methylformamide (manufactured by Nacalai Tesque, reagent) as a conductivity improver (100 parts of conductive polymer) 1730 parts), ethanol (manufactured by Nacalai Tesque, reagent) 514 parts (when the conductive polymer is 100 parts, 46 parts 727 parts) and 48 parts of ion-exchanged water (4364 parts when the conductive polymer is 100 parts) were used to prepare a uniform aqueous dispersion.

Next, the dispersion was applied to a non-alkali glass plate, and the film was formed by heating in an oven at 130 ° C. for 30 minutes to obtain a test piece having an antistatic film on the surface. In addition, the dry film thickness in a test piece was calculated and adjusted from the application amount of the aqueous dispersion.
MS-51: In the above general formula representing an alkoxysilane oligomer, R ₁ = R ₂ = methyl group, R ₃ = R ₄ = methoxy group, weight average molecular weight 500-700 (catalog value), n = 4-7 (weight) Calculated from average molecular weight)

(Example 2)
Instead of Baytron PH500 (manufactured by HC Starck) of Example 1, Baytron PH1000 (manufactured by HC Starck, D50 is 52 nm, containing 1.1 parts of the conductive polymer), A test piece was obtained in the same manner as in Example 1.

(Example 3)
Instead of Baytron PH500 (manufactured by HC Starck Co., Ltd.) of Example 1, Baytron P (manufactured by HC Starck Co., D50 of 140 nm, containing 1.1 parts of the conductive polymer) was used. A test piece was obtained in the same manner as in Example 1.

(Comparative Example 1)
Instead of Baytron PH500 (manufactured by HC Starck) of Example 1, Baytron HC V4 (manufactured by HC Starck, D50 of 570 nm, containing 1.1 parts of the conductive polymer) was used. A test piece was obtained in the same manner as in Example 1.

(Examples 4 to 7)
A test piece was obtained in the same manner as in Example 1 except that the amount of the alkoxysilane oligomer MS-51 as a binder was changed as shown in Table 2.

(Examples 8 and 9)
In addition to each component of Example 1, Z-6043 (manufactured by Toray Dow Corning Co.), which is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, was used in an amount shown in Table 3, A test piece was obtained in the same manner as in Example 1.

(Example 10)
In addition to each component of Example 1, Z-6040 (manufactured by Toray Dow Corning), which is 3-glycidoxypropyltrimethoxysilane, was further used in the same manner as in Example 1 using the amounts shown in Table 4. A test piece was obtained.

(Example 11)
In addition to the components of Example 1, a test piece was obtained in the same manner as in Example 1 using BYK-301 (manufactured by Big Chemie), which is a polyether-modified polydimethylsiloxane, in the amounts shown in Table 4. .

(Example 12)
A test piece was obtained in the same manner as in Example 1 except that 24 parts of MS-56 (manufactured by Mitsubishi Chemical Corporation) was used instead of 24 parts of alkoxysilane oligomer MS-51 (manufactured by Mitsubishi Chemical Corporation) of Example 1. It was.
MS-56: In the above general formula representing an alkoxysilane oligomer, R ₁ = R ₂ = methyl group, R ₃ = R ₄ = methoxy group, weight average molecular weight 1100-1300 (catalog value), n = 10-12 (weight) Calculated from average molecular weight)

(Comparative Examples 2 to 4)
A test piece was obtained in the same manner as in Example 1 except that 24 parts of each of the following binders were used instead of 24 parts of the alkoxysilane oligomer MS-51 (manufactured by Mitsubishi Chemical Corporation) of Example 1.

Comparative Example 2: Monomer (Alkoxysilane monomer (excluding siloxane bond), methyltrimethoxysilane): Z-6366 (Toray Dow Corning)
Comparative Example 3: Polyester resin: Plus Coat RZ-105 (manufactured by Kyogo Chemical Co., Ltd.)
Comparative Example 4: Epoxy silane compound: Z-6040 (manufactured by Dow Corning Toray)

(Example 13)
A test was conducted in the same manner as in Example 1 except that 19 parts of N-methylpyrrolidone (manufactured by Nacalai Tesque, reagent) was used instead of 19 parts of N-methylformamide (manufactured by Nacalai Tesque, Inc.). I got a piece.

(Examples 14 to 17)
A test piece was obtained in the same manner as in Example 1 except that the dry film thickness was changed as described in Table 7 by adjusting the coating amount of the aqueous dispersion of Example 1.

(Example 18)
The aqueous dispersion of Example 1 was applied to a PET film (Luminer T-60, manufactured by Toray Industries, Inc.) instead of a glass plate, and heated in an oven at 130 ° C. for 30 minutes to form a film. The test piece which has on the surface was obtained.

(Comparative Example 5)
In this comparative example, the first embodiment of Patent Document 1 (Japanese Patent Laid-Open No. 10-96953) was verified. That is, according to the description of [0051], an ethanol solution of 1 g of 3,4-ethylenedioxythiophene and 5 g of ferric p-toluenesulfonic acid was applied on an alkali-free glass, dried by heating in an oven, and organic A conductive film was formed to prepare a test piece.

(Comparative Example 6)
In this comparative example, the fifth embodiment of Patent Document 1 (Japanese Patent Laid-Open No. 10-96953) was verified. That is, according to the description of [0070], on an alkali-free glass, 3,4-ethylenedioxythiophene lg, p-toluenesulfonic acid ferric iron 2 g, and polyvinyl acetate 5 g in an isopropanol-acetone (1: 1) mixture. After applying the dissolved solution, the applied substrate was dried by heating. Furthermore, it wash | cleaned with running water and dried and produced the test piece.

(Comparative Example 7)
In this comparative example, a conventional antistatic film using an inorganic ITO was verified. That is, an ITO film was formed on a glass substrate by a sputtering method to produce a test piece.

  The physical properties of the test pieces obtained in the above examples and comparative examples were evaluated by the following methods.

(1) Film strength The film strength (pencil hardness) of the antistatic film of each test piece was measured using a pencil scratch hardness tester manufactured by Yasuda Seiki Seisakusho Co., Ltd. according to the test method of JIS-K5600-5-4. .

(2) Adhesiveness The adhesiveness of each test piece to the base material of the antistatic film was evaluated according to a cross-cut peel test of JIS K5400. Evaluation was performed in the following three stages.

◎: 10 points, ○: 8 points, ×: 6 points or less (3) Total light transmittance (%), haze (%)
The total light transmittance and haze of each test piece were measured according to JIS K7150 using a haze computer HGM-2B (trade name) manufactured by Suga Test Instruments Co., Ltd.

(4) Surface resistivity (Ω / □)
The surface resistivity of the antistatic film of each test piece was measured according to JIS K7194 using a Hiresta UP (MCP-HT-450, trade name) manufactured by Mitsubishi Chemical Corporation with a probe UA and an applied voltage of 10V to 500V.

(5) Refractive index The refractive index of each test piece was measured with an ellipsometer DHA-XA2 / S6 (trade name) manufactured by Ikejiri Optical Co., Ltd. at a wavelength of 632.8 nm.

(6) Chemical resistance After immersing each test piece in a solvent (sodium hydroxide aqueous solution or acetone solution), the surface resistivity and film strength were measured as described above, and the results were measured in three stages based on the following criteria. evaluated. The immersion condition in the aqueous sodium hydroxide solution was immersion for 2 minutes at room temperature. The immersion condition in acetone was immersion for 1 hour at room temperature.
○: Surface resistivity is 10th power or less and film strength is pencil hardness B or more Δ: Surface resistivity is 10th power or less, or film strength is pencil hardness B or more ×: Surface resistivity is 10th power or more and film strength is Pencil hardness B or less The results obtained above are shown in Tables 1 to 8 below.

In Comparative Examples 5 and 6 in Table 8, the refractive index could not be measured because the surface of the antistatic film formed was rough.

  From Examples 1 to 3 and Comparative Example 1 in Table 1, it is essential that the conductive polymer particles have a particle size of 200 nm or less. If the particle size exceeds 200 nm, the surface resistivity increases (that is, the conductivity). Is low) and it is found that the chemical resistance is poor.

  From Examples 1 and 12 and Comparative Examples 2 to 4 in Table 5, when an alkoxysilane oligomer is used as a binder component, the chemical resistance is excellent and the film hardness is high, but when an alkoxysilane monomer is used, the chemical resistance is high. When the polyester silane compound or the epoxy silane compound is used, the film hardness is lowered in addition to the chemical resistance.

  From Examples 1 and 4 to 7 in Table 2, when the use amount of the alkoxysilane oligomer is in the range of 150 to 10,000 parts by weight with respect to 100 parts by weight of the conductive polymer particles, the excellent effect of the present invention is achieved. I understand.

  From Examples 1, 8 and 9 in Table 3 and Examples 10 and 11 in Table 4, the composition of the present invention contains an alkoxysilane in the binder component even when it contains a binder component other than the alkoxysilane oligomer. It turns out that the outstanding effect of this invention is achieved when the ratio of an oligomer exists in the range of 97 to 100 weight%.

  From Example 1 and Examples 14 to 17 in Table 7, it can be seen that the excellent effect of the present invention is achieved when the dry film thickness of the antistatic film is in the range of 25 to 380 nm.

  From Example 18 of Table 8, it can be seen that the excellent effect of the present invention can be achieved even when applied to a PET substrate other than alkali-free glass.

  The conductive coating composition according to the present invention is used as a base material in liquid crystal displays (LCDs), electroluminescent displays, plasma displays, electrochromic displays, solar cells, batteries, capacitors, chemical sensors, display elements, semiconductor materials, electromagnetic shielding materials, etc. Can be used to form a conductive film or an antistatic film on the substrate. Moreover, it can be used also as a conductive paint for applying to glasses, glasses, etc., or a rust preventive paint.

1 Color filter 2 Glass substrate 3 Antistatic layer 4 Polarizing plate

Claims (11)

Conductive polymer particles having a particle size (D50) of 200 nm or less, and a binder component containing an alkoxysilane oligomer represented by the following general formula:
Only including,
The total amount of the binder component is 150 to 10,000 parts by weight with respect to 100 parts by weight of the conductive polymer particles,
The electroconductive coating composition whose compounding quantity of the said alkoxysilane oligomer in the said binder component is 97-100 weight% .

In the formula, R ₁ and R ₂ are the same or different and each represents an alkyl group having 1 to 4 carbon atoms. R ₃ and R ₄ are the same or different and represent H (hydrogen atom), a hydroxyl group, or an alkoxy group having 1 to 4 carbon atoms. However, at least one of the plurality of R ₃ and R ₄ is an alkoxy group. n represents an integer of 2 to 20.   The conductive coating composition according to claim 1, wherein the conductive polymer particles have a particle size of 60 nm or less.   The conductive coating composition according to claim 1, wherein the conductive polymer particles have a particle size of 30 nm or less. It said conductive polymer is poly (3,4-disubstituted thiophene) and a complex of the polyanion, conductive coating composition according to any one of claims 1-3. Further comprising a conductivity enhancing agent, conductive coating composition according to any one of claims 1-4. The conductive coating composition according to claim 5 , wherein the conductivity improver is at least one selected from the group consisting of N-methylformamide and N-methylpyrrolidone. It is used to form an antistatic layer included in the liquid crystal display device, the conductive coating composition according to any one of claims 1-6. A laminate including a base material and a conductive film provided on the base material,
The conductive layer is one formed from a conductive coating composition according to any one of claims 1 to 7 laminate. The laminated body of Claim 8 whose dry film thickness of the said electrically conductive film is 25-380 nm. The laminate according to claim 8 or 9 , wherein the base material is a glass substrate. The laminated body of Claim 10 contained in a liquid crystal display device.