WO2022091432A1

WO2022091432A1 - Electrically conductive composition, electrically conductive film, and non-contact medium

Info

Publication number: WO2022091432A1
Application number: PCT/JP2020/048831
Authority: WO
Inventors: 晃太郎水野; 章史桑原; 稔彦田中; 順幸諸石
Original assignee: 東洋インキＳｃホールディングス株式会社
Priority date: 2020-10-30
Filing date: 2020-12-25
Publication date: 2022-05-05
Also published as: TW202216920A; JP2022073002A

Abstract

The present invention provides: an electrically conductive composition having particularly exceptional electrical conductivity, adhesion, and durability; an electrically conductive film in which said electrically conductive composition is used; and a non-contact medium that offers exceptional communication performance inexpensively.　The problem noted above is solved by an electrically conductive composition that contains a binder resin (A), a carbon material (B), and a curing agent (C), the carbon material (B) containing graphite (B-1) and a carbon material (B-2) other than graphite, the carbon material (B) content being 65-85 mass% in 100 mass% of solid content of the electrically conductive composition, and the graphite (B-1) content being 70.0-99.0 mass% in 100 mass% of the carbon material (B).

Description

Conductive compositions, conductive and non-contact media

The present invention relates to a conductive composition, and a conductive film and a non-contact medium using the conductive composition.

In recent years, the development of electronics has been remarkable, and there is a demand for low cost products and long life in various usage environments for conductive materials used in various electronic parts and devices. ing. For example, when manufacturing a conductive circuit of an electronic component such as a non-contact type medium, a board wiring of an electronic device, a wiring for connecting an electronic device, or the like, a conductive composition having good conductivity is required. Here, a conductive composition using a metal filler such as silver or copper is generally used as a conductive substance that imparts conductivity, but these metal fillers have a great problem in terms of cost. rice field.

On the other hand, various conductive compositions using conductive carbon that does not use a metal as a conductive substance have been studied, but the conductivity may be insufficient, and they are used in semi-conductive applications such as antistatic applications. Was limited to.

Therefore, Patent Documents 1 to 3 propose conductive compositions using carbon materials having a low volume resistivity of less than ^10-2 Ω · cm, such as graphite and carbon nanotubes, as conductive substances. However, although these carbon materials show high conductivity, many of them have a large specific surface area, and it may be difficult to uniformly mix and disperse them in a resin or a solvent. Therefore, when a coating film or a molded product is produced using a conductive composition containing the carbon material, resin, solvent, etc., the conductivity is sufficiently exhibited due to poor contact between the carbon materials in the coating film or the molded product. Sometimes I couldn't.

Further, as a method for improving the dispersibility, a method using a dispersant can be considered, but the use of the dispersant may reduce the conductivity.

Further, usually, a resin component which is an organic material is added to the conductive composition for the purpose of dispersing the filler, adhering the fillers to each other, and adhering the conductive composition to the base material. However, such an organic material is liable to deteriorate in a temperature and humidity environment in an outdoor environment, and its characteristics as a conductive composition may deteriorate with time, which has a problem in durability. As described above, the conductive composition is required to have both adhesiveness and durability in addition to the conductivity.

Japanese Unexamined Patent Publication No. 3-7740 Japanese Unexamined Patent Publication No. 2001-60413 Japanese Patent Application Laid-Open No. 2002-20515

An object of the present invention is to provide a conductive composition having specifically excellent in conductivity, adhesion and durability, and a conductive film using the same. Further, an object of the present invention is to provide a non-contact type medium having a conductive circuit using the conductive composition and having excellent communication performance at low cost.

The present invention is a conductive composition containing a binder resin (A), a carbon material (B), and a curing agent (C).
The carbon material (B) contains graphite (B-1) and a carbon material other than graphite (B-2).
The content of the carbon material (B) is 65 to 85% by mass in 100% by mass of the solid content of the conductive composition.
The content of graphite (B-1) is 70.0 to 99.0% by mass in 100% by mass of the carbon material (B).

In the conductive composition of the present invention, the content of the curing agent (C) is preferably 0.5 to 20% by mass with respect to 100% by mass of the binder resin (A).

In the conductive composition of the present invention, the content of graphite (B-1) is preferably 80.0 to 99.0% by mass in 100% by mass of the carbon material (B).

In the conductive composition of the present invention, the content of graphite (B-1) is more preferably 90.0 to 97.5% by mass in 100% by mass of the carbon material (B).

In the conductive composition of the present invention, the content of the carbon material (B) is preferably 70 to 80% by mass based on 100% by mass of the solid content of the conductive composition.

In the conductive composition of the present invention, the curing agent (C) preferably contains an aziridine compound or an epoxy group-containing compound.

In the conductive composition of the present invention, the curing agent (C) preferably contains a metal chelate.

In the conductive composition of the present invention, the metal chelate preferably contains an aluminum chelate.

Further, the present invention is a conductive film formed by forming the above-mentioned conductive composition into a film.

Further, the present invention is a non-contact type medium loaded with a conductive circuit made of the above-mentioned conductive composition and an IC chip.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a conductive composition having specifically excellent in conductivity, adhesion and durability, and a conductive film using the same. Further, according to the present invention, it is possible to provide a non-contact type medium having a conductive circuit using the conductive composition and having excellent communication performance at low cost.

<< Conductive composition >>
The conductive composition of the present invention (hereinafter, may be referred to as the present conductive composition) includes a binder resin (A), a carbon material (B), a curing agent (C), and a solvent (if necessary). D) and.

In this conductive composition, the blending ratio of graphite, which is a carbon material as a conductive substance, and carbon other than graphite is within a specific range. Therefore, the durability of the binder resin and the contact and binding properties of the carbon materials in the conductive film formed by the conductive composition are improved, and an excellent conductive network can be formed, and the conductivity and durability can be improved. Further, it is possible to provide a conductive film having excellent adhesion.

The appropriate viscosity of the present conductive composition depends on the coating method of the conductive composition, but is preferably 10 mPa · s or more and 30,000 mPa · s or less.

<Binder resin (A)>
First, the binder resin (A) will be described.

The binder resin (A) includes polyurethane-based, polyamide-based, acrylonitrile-based, acrylic-based, butadiene-based, polyvinyl butyral-based, polyolefin-based, polyester-based, polystyrene-based, EVA-based, epoxy-based, polyvinylidene fluoride-based, and silicon-based resins. It can contain one or more species selected from the group consisting of. However, it is not limited to these resins. The binder resin (A) may be used alone or in combination of two or more.

The binder resin (A) can also be a curable resin that undergoes a curing (crosslinking) reaction after the binder resin is applied to the substrate.
That is, the binder resin (A) is selected to be self-curing, or combined with a curing agent described later, and the conductive composition is printed or coated on the substrate, and then the reaction is performed. That is, it can be cured (crosslinked).

Further, as the binder resin (A), one that moderately softens and flows during (heat) pressing is preferable. When the conductive composition containing the binder resin (A) is printed or coated on the substrate and then (heat) pressed, the resin component is softened and the conductive film during printing and coating is flat. It flows in the thickness direction while almost maintaining the pattern shape. As a result, the voids in the conductive film can be reduced, and the contact between the carbon materials (B) which are the conductive substances can be increased, so that the volume resistivity of the obtained conductive film can be expected to decrease.

From the above, it is preferable to use at least one of polyurethane resin, polyamide resin and polyester resin as the binder resin (A) from the viewpoint of volumetric resistance, adhesion to the substrate and durability.

(Polyurethane resin)
As the polyurentane resin, conventionally known ones can be used, and the synthesis method thereof is not particularly limited. For example, as the polyurethane resin, those obtained by the following synthetic methods can be used.
1) A method of reacting a polyol compound (a) with a diisocyanate (b).
2) A method of reacting a polyol compound (a) with a diisocyanate (b) with a diol compound (c) having a carboxyl group to obtain a urethane prepolymer (d) having an isocyanate group.
3) A method of further reacting the urethane prepolymer (d) with the polyamino compound (e).
As the polyurethane resin, a polyurethane resin obtained by reacting with a reaction terminator in the above three methods may be used, if necessary.

-Polyform compound (a)
As the polyol compound (a), conventionally known polyol components can be appropriately used as the polyol component constituting the polyurethane resin. Examples of the polyol compound (a) include polyether polyols (a-1), polyester polyols (a-2), polycarbonate polyols (a-3), polybutadiene glycols (a-4), or these. Mixtures and the like can be used.

Examples of the polyether polyols (a-1) include polymers or copolymers of ethylene oxide, propylene oxide, tetrahydrofuran and the like.

Examples of the polyester polyols (a-2) include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, and pentanediol, 3. -Saturated and unsaturated low molecular weight diols such as methyl-1,5-pentanediol, hexanediol, octanediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, dimerdiol, and n- Alkyl glycidyl ethers such as butyl glycidyl ether and 2-ethylhexyl glycidyl ether, monocarboxylic acid glycidyl esters such as versatic acid glycidyl ester, and adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, and succinic acid. Dicarboxylic acids such as acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, or polyester polyols and cyclic ester compounds obtained by dehydration condensation of these anhydrides. Examples thereof include polyester polyols obtained by ring-opening polymerization.

As the polycarbonate polyols (a-3), 1) a reaction product of diol or bisphenol and carbonic acid ester, and 2) a reaction product of diol or bisphenol with phosgene in the presence of alkali can be used.

Examples of the carbonic acid ester include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, propylene carbonate and the like.
The diols include ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, butylene glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 3,3. '-Dimethylol heptane, polyoxyethylene glycol, polyoxypropylene glycol, propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9 -Nonandiol, neopentyl glycol, octanediol, butylethylpentanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol, 3,9-bis (1,1-dimethyl-2-hydroxyethyl, 2,2) , 8,10-Tetraoxospiro [5.5] Undecane and the like.
Examples of bisphenol include bisphenol A, bisphenol F, and bisphenols obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to bisphenols.

The number average molecular weight (Mn) of the polyol compound (a) is appropriately determined in consideration of the solubility of the polyurethane resin in producing the conductive composition, the durability of the conductive film formed, the adhesive strength to the substrate, and the like. Can be decided. The Mn of the polyol compound (a) is preferably in the range of 580 to 8000, more preferably in the range of 1000 to 5000.

The above-mentioned polyol compound (a) may be used alone or in combination of two or more. Further, as long as the performance of the polyurethane resin is not lost, a part of the polyol compound (a) can be replaced with small molecule diols, for example, various small molecule diols used for producing the polyol compound.

-Diisocyanate compound (b)
As the diisocyanate compound (b), conventionally known compounds can be appropriately used, for example, aromatic diisocyanate (b-1), aliphatic diisocyanate (b-2), alicyclic isocyanate (b-3), or these. Mixtures can be used.

Examples of the aromatic diisocyanate (b-1) include 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-benzyl isocyanate, dialkyldiphenylmethane diisocyanate, and tetra. Examples thereof include alkyldiphenylmethane diisocyanate, 1,3-phenylenediocyanate, 1,4-phenylenediocyanate, tolylene diisocyanate, and xylylene diisocyanate.

Examples of the aliphatic diisocyanate (b-2) include butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate.

Examples of the alicyclic diisocyanate (b-3) include cyclohexane-1,4-diisocyanate, isophorone diisocyanate, norbornane diisocyanatomethyl, bis (4-isocyanatecyclohexyl) methane, 1,3-bis (isocyanatemethyl) cyclohexane, and methyl. Cyclohexanediisocyanate and the like can be mentioned.

Among these, it is preferable to use isophorone diisocyanate as the diisocyanate compound (b).

-A diol compound having a carboxyl group (c)
Examples of the diol compound (c) having a carboxyl group include dimethylol alkanoic acid such as dimethylol acetic acid, dimethylol propionic acid, dimethylol butanoic acid and dimethylol pentanoic acid, dihydroxysuccinic acid and dihydroxybenzoic acid. Among these, from the viewpoint of reactivity and solubility, it is preferable to use at least one of dimethylol propionic acid and dimethylol butanoic acid as the diol compound (c).

-Polyamino compound (e)
The polyamino compound (e) acts as a chain extender, and for example, the following can be used. That is, in addition to amines such as ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, norbornandiamine, 2- (2-aminoethylamino) ethanol. , 2-Hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxypropylethylenediamine and other amines having hydroxyl groups can also be used. Among these, isophorone diamine is preferably used as the polyamino compound (e).

The condition for reacting the polyol compound (a) with the diisocyanate (b) and the diol compound (c) having a carboxyl group to obtain the urethane prepolymer (d) having an isocyanate group is that the isocyanate group is excessive in the reaction system. There is no particular limitation other than making it exist. However, the equivalent ratio of isocyanate groups / hydroxyl groups in the reaction system is preferably in the range of 1.05 / 1 to 3/1, more preferably in the range of 1.2 / 1 to 2/1. .. The reaction is usually carried out at a temperature in the range of room temperature (eg, 25 ° C.) to 150 ° C. From the viewpoint of manufacturing time and control of side reactions, the reaction is preferably carried out at a temperature in the range of 60 to 120 ° C.

When synthesizing a polyurethane resin by reacting a urethane prepolymer (d) having an isocyanate group with a polyamino compound (e), a reaction terminator can be used to adjust the molecular weight of the obtained polyurethane resin. As the reaction terminator, for example, dialkylamines such as di-n-butylamine, dialkanolamines such as diethanolamine, and alcohols such as ethanol and isopropyl alcohol can be used.

There are no particular restrictions on the conditions under which the urethane prepolymer (d) having an isocyanate group, the polyamino compound (e), and the reaction terminator, if necessary, are reacted. However, when the number of free isocyanate groups at both ends of the urethane prepolymer is one equivalent, the total equivalent of the polyamino compound (e) and the amino groups in the reaction terminator is in the range of 0.5 to 1.3. Is preferable. The total equivalent of the amino groups is more preferably in the range of 0.8 to 0.995.

The weight average molecular weight (Mw) of the polyurethane resin is preferably in the range of 5000 to 200,000 from the viewpoint of coatability and handleability.

When synthesizing polyurethane resin, one type of solvent can be used alone, or two or more types can be used in combination. Examples of the solvent include an ester solvent, a ketone solvent, a glycol ether solvent, an aliphatic solvent, an aromatic solvent, an alcohol solvent, a carbonate solvent, water and the like.

Examples of the ester solvent include ethyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, amyl acetate, ethyl lactate and the like.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone benzene, diisobutyl ketone, diacetone alcohol, isophorone, cyclohexanenone and the like.

Examples of the glycol ether-based solvent include ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, and acetates of these monoethers, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, and propylene. Examples thereof include glycol monomethyl ethers, propylene glycol monoethyl ethers, and acetates of these monoethers.

Examples of the aliphatic solvent include n-heptane, n-hexane, cyclohexane, methylcyclohexane, ethylcyclohexane and the like.

Examples of the aromatic solvent include toluene, xylene and the like.

Examples of the alcohol solvent include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, cyclohexanol and the like.

Examples of the carbonate solvent include dimethyl carbonate, ethylmethyl carbonate, di-n-butyl carbonate and the like.

(Polyamide resin)
The polyamide resin in the present specification is a general term for polymers having an amide bond obtained by various reactions such as polycondensation of dibasic acid and diamine, polycondensation of aminocarboxylic acid, and ring-opening polymerization of lactam. .. Therefore, the polyamide resin is a product manufactured from a reaction product partially hydrogenated, including various modified polyamides, a product obtained by partially copolymerizing other monomers, or other substances such as various additives. It is a broad concept including a mixture of.

The polyamide resin is not particularly limited as long as the above conditions are satisfied, but is preferably a dimer acid-modified polyamide resin obtained by polycondensing a dibasic acid containing dimer acid as a main component and polyamines. .. The main component means the component having the highest blending ratio (for example, mol% content) among all the components contained in the target (here, dibasic acid).

The dimer acid may be a dimer acid obtained by polymerizing a natural monobasic unsaturated fatty acid contained in a tall oil fatty acid, a soybean oil fatty acid, or the like, or may be a saturated fatty acid group, an unsaturated fatty acid group, or an alicyclic type. Alternatively, it may be various dicarboxylic acids such as aromatic acids.

Commercially available products of the dimer acid include Hari Dimer 200, 300 (trade name, manufactured by Harima Chemicals, Inc.), Versa Dime 228, 216, Empole 1018, 1019, 1061, 1062 (all trade names, manufactured by Cognis Co., Ltd.) and the like. Can be mentioned.

Further, hydrogenated dimer acid can also be used, and examples of commercially available hydrogenated dimer acid include Prepole 1009 (trade name, manufactured by Croda Japan Co., Ltd.) and Empole 1008 (trade name, manufactured by Cognis Co., Ltd.).

In addition to the above dimer acid, various dicarboxylic acids can be used as the dibasic acid in order to obtain a polyamide resin having appropriate flexibility. Specific examples of the dicarboxylic acid include oxalic acid, malonic acid, (anhydrous) succinic acid, (anhydrous) maleic acid, glutaric acid, adipic acid, bimeric acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid. Acids, phthalic acids, naphthalenedicarboxylic acids, 1,3- or 1,4-cyclohexanedicarboxylic acids, 1,18-octadecanedicarboxylic acids, 1,16-hexadecanedicarboxylic acids and the like are used.

Further, a dibasic acid having a phenolic hydroxyl group can also be used. By using a dibasic acid having a phenolic hydroxyl group, the phenolic hydroxyl group can be introduced into the side chain of the polyamide resin and can be used for the reaction with the curing agent.

Examples of the dibasic acid having a phenolic hydroxyl group include hydroxyisophthalic acid such as 2-hydroxyisophthalic acid, 4-hydroxyisophthalic acid and 5-hydroxyisophthalic acid, 2,5-dihydroxyisophthalic acid and 2,4-dihydroxyisophthalic acid. Dihydroxyisophthalic acid such as 4,6-dihydroxyisophthalic acid, 2-hydroxyterephthalic acid, 2,3-dihydroxyterephthalic acid, dihydroxyterephthalic acid such as 2,6-dihydroxyterephthalic acid, 4-hydroxyphthalic acid, 3-hydroxyphthalic acid Examples thereof include hydroxyphthalic acid such as acid, dihydroxyphthalic acid such as 3,4-dihydroxyphthalic acid, 3,5-dihydroxyphthalic acid, 4,5-dihydroxyphthalic acid and 3,6-dihydroxyphthalic acid.
Further, these acid anhydrides and ester derivatives such as polybasic acid methyl ester can also be mentioned.
Among these, 5-hydroxyisophthalic acid is preferable as the dibasic acid from the viewpoint of copolymerizability and easy availability.

Further, in order to obtain a polyamide resin having appropriate fluidity when heated, various monocarboxylic acids may be used if necessary. Specifically, as the monocarboxylic acid, propionic acid, acetic acid, caprylic acid (octanoic acid), stearic acid, oleic acid and the like are used.

Examples of polyamines as reactants for producing the dimer acid-modified polyamide resin include various diamines such as aliphatic, alicyclic and aromatic, triamine and polyamine.

Specific examples of the above diamines include ethylenediamine, propanediamine, butanediamine, triethylenediamine, tetraethylenediamine, hexamethylenediamine, p- or m-xylene diamine, 4,4'-methylenebis (cyclohexylamine), and 2,2-bis. -(4-Cyclohexylamine), polyglycoldiamine, isophoronediamine, 1,2-, 1,3- or 1,4-cyclohexanediamine, 1,4-bis- (2'-aminoethyl) benzene, N-ethyl Amino piperazine, piperazine and the like can be mentioned. Further, a dimer diamine obtained by converting a dimerized aliphatic nitrile group and reducing it with hydrogen can also be used.

Alkanolamine may be used in combination with the diamine. Examples of the alkanolamine include ethanolamine, propanolamine, diethanolamine, butanolamine, 2-amino-2-methyl-1-propanol, 2- (2-aminoethoxy) ethanol and the like.
Further, as the diamine, a polyether diamine having oxygen in the skeleton can be used. This polyether diamine has a general formula: H ₂ N-R _1- (RO) _n -R ₂ -NH ₂ (in the formula, n is an integer of 2 to 100, and R ₁ and R ₂ have carbon atoms. It is an allene group or a divalent alicyclic hydrocarbon group having 1 to 14 elements, and R is an alkylene group having 1 to 10 carbon atoms or a divalent alicyclic hydrocarbon group. May be linear or branched.). Examples of the polyether diamine include polyoxypropylene diamine, and commercially available products include Jeffamines (manufactured by San Techno Chemical Co., Ltd.). Further, examples of the polyether diamine include bis- (3-aminopropyl) -polytetrahydrofuran.

Further, specific examples of triamine include diethylenetriamine and the like.
Specific examples of polyamines include triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine and the like.
Further, as the polyamine, a compound obtained by converting a carbosyl group of a polybasic acid compound having a cyclic or acyclic hydrocarbon group having 20 to 48 carbon atoms into an amino group can be used.
Examples of commercially available polyamines include, for example, the product names of Croda Japan Co., Ltd .: "Priamine 1071", "Priamine 1073", "Priamine 1074", "Priamine 1075", and the product names of Cognis Japan Co., Ltd .: "Versamine 551". Can be mentioned.

The above polyamines and dimer acid or various dicarboxylic acids are heat-condensed by a conventional method, and various polyamide resins including dimer acid-modified polyamide resin are produced by an amidation step accompanied by dehydration. Usually, the reaction temperature is about 100 to 300 ° C., and the reaction time is about 1 to 8 hours.

(Polyester resin)
The polyester resin is a polymer composed of a polyvalent carboxylic acid as a monomer and a polyhydric alcohol. As the polyester resin, known ones can be used and are not particularly limited. However, from the viewpoint of ensuring the cohesive force of the resin, the weight average molecular weight (Mw) of the polyester resin is preferably 1000 to 100,000. Further, from the viewpoint of adhesion, the glass transition temperature (Tg) of the polyester resin is preferably −10 ° C. to 200 ° C.

Examples of the polyvalent carboxylic acid component constituting the polyester resin include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, unsaturated dicarboxylic acids, and trivalent or higher carboxylic acids.
On the other hand, examples of the polyhydric alcohol component constituting the polyester resin include aliphatic glycols, ether glycols, and trihydric or higher polyalcohols.
As for the polyvalent carboxylic acid and the polyhydric alcohol, one type may be used alone, or two or more types may be used in combination.

Commercially available polyester resins include Byron (manufactured by Toyobo Co., Ltd., "Byron" is a registered trademark), Polyester (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., "Polyester" is a registered trademark), and Tesslac (Hitachi Kasei Polymer Co., Ltd.). , "Teslac" is a registered trademark).

<Carbon material (B)>
Next, the carbon material (B) will be described.

In the present conductive composition, the carbon material (B) acting as a conductive substance contains graphite (B-1) and a carbon material (B-2) other than graphite.
The content of the carbon material (B) is 65 to 85% by mass, preferably 70 to 80% by mass, based on 100% by mass of the solid content of the conductive composition.

When the content of the carbon material (B) exceeds 85% by mass, the resin content is insufficient, the adhesiveness of the conductive film is lowered, and the adhesion is poor. On the other hand, when the content of the carbon material (B) is less than 65% by mass, the contact between the carbon materials in the conductive film is reduced, and the conductivity becomes poor.

When the content of the carbon material (B) is 70 to 80% by mass, high conductivity and adhesion can be easily exhibited in a state where the conductive network formation in the conductive film formed by the conductive composition is good. ..

(Graphite (B-1))
As the graphite (B-1), for example, artificial graphite, natural graphite, or the like can be used. Artificial graphite is obtained by artificially orienting irregularly arranged micrographite crystals by heat treatment of amorphous carbon, and is usually produced using petroleum coke or coal-based pitch coke as a main raw material. As the natural graphite, scaly graphite, lump graphite, earth graphite and the like can be used. It is also possible to use expanded graphite (also referred to as expandable graphite) obtained by chemically treating scaly graphite, or expanded graphite obtained by heat treatment and expansion of expanded graphite and then miniaturization or pressing. You can. Among these graphites, when used for a conductive film of a wiring sheet, flaky graphite such as scaly graphite, expanded graphite, and flaky graphite is preferable from the viewpoint of conductivity.

The surface of these graphites is treated with surface treatments such as epoxy treatment, urethane treatment, silane coupling treatment, and so on, in order to increase the affinity with the binder resin (A) as long as the characteristics of the conductive composition are not impaired. It may be subjected to an oxidation treatment or the like.

The average particle size of the graphite (B-1) used is preferably 2 to 100 μm, more preferably 20 to 50 μm.

When the average particle size of graphite (B-1) is 2 μm or more, the aspect ratio of the graphite particles can be set in an appropriate range, the contact between the graphite particles is prevented from becoming point contact, and a sufficient conductive network. Can be easily formed. Further, if the average particle size of graphite (B-1) is 100 μm or less, the voids between the graphite particles can be made into an appropriate size, and the conductive path formed between carbon materials other than graphite in the conductive network. , The ratio with the conductive path via graphite can be set in an appropriate range, and excellent conductivity can be imparted.

The average particle size in the present specification means a particle size (D50) that becomes 50% when the volume ratio of the particles is integrated from the fine particle size distribution in the volume particle size distribution. The average particle size can be measured with a general particle size distribution meter, for example, a dynamic light scattering type particle size distribution meter (manufactured by Nikkiso Co., Ltd., trade name: "Microtrack UPA") or the like.

Examples of commercially available graphite (B-1) include the following.
As flaky graphite, for example, trade names manufactured by Nippon Graphite Industry Co., Ltd .: CMX, CPB, UP-5, UP-10, UP-20, UP-35N, CSSP, CSPE, CSP, CP, CB-150, CB- 100, ACP, ACP-100, ACB-50, ACB-100, ACB-150, SP-10, SP-20, J-SP, SP-270, HOP, GR-15, LEP, F # 1, F # 2, F # 3; Product names manufactured by Chuetsu Graphite Co., Ltd .: CX-3000, FBF, BF, CBR, SSC-3000, SSC-600, SSC-3, SSC, CX-600, CPF-8, CPF-3, CPB-6S, CPB, 96E, 96L, 96L-3, 90L-3, CPC, S-87, K-3, CF-80, CF-48, CF-32, CP-150, CP-100, CP, HF-80, HF-48, HF-32, SC-120, SC-80, SC-60, SC-32; Product names manufactured by Ito Graphite Industry Co., Ltd .: EC1500, EC1000, EC500, EC300, EC100, EC50; Nishimura Trade names manufactured by Graphite Co., Ltd .: 10099M, PB-99 and the like can be mentioned.
Examples of the spherical natural graphite include trade names: CGC-20, CGC-50, CGB-20, and CGB-50 manufactured by Nippon Graphite Industry Co., Ltd.
Examples of the earth-like graphite include trade names manufactured by Nippon Graphite Industry Co., Ltd .: Blue P, AP, AOP, P # 1; trade names manufactured by Chuetsu Graphite Co., Ltd .: APR, S-3, AP-6, 300F. ..
As artificial graphite, for example, trade names manufactured by Nippon Graphite Industry Co., Ltd .: PAG-60, PAG-80, PAG-120, PAG-5, HAG-10W, HAG-150; trade names manufactured by Chuetsu Graphite Co., Ltd .: RA- 3000, RA-15, RA-44, GX-600, G-6S, G-3, G-150, G-100, G-48, G-30, G-50; Product name manufactured by SEC Carbon Co., Ltd .: SGP-100, SGP-50, SGP-25, SGP-15, SGP-5, SGP-1, SGO-100, SGO-50, SGO-25, SGO-15, SGO-5, SGO-1, SGX- Examples thereof include 100, SGX-50, SGX-25, SGX-15, SGX-5, and SGX-1.
The graphite (B-1) is not limited to these. Further, graphite (B-1) may be used alone or in combination of two or more.

The content of graphite (B-1) in 100% by mass of the carbon material (B) in the present conductive composition is 70.0 to 99.0% by mass, and 75.0 to 99.0% by mass. It is preferably 80.0 to 99.0% by mass, more preferably 90.0 to 97.5% by mass, and most preferably 90.0 to 97.5% by mass.

When the content of graphite (B-1) in the carbon material (B) is less than 70.0% by mass, the orientation of the graphite particles is lowered due to the excess amount of the carbon material (B-2) other than graphite. Furthermore, since most of the conductive network is occupied by carbon materials other than graphite, specific high conductivity is not exhibited. On the other hand, when the content of graphite (B-1) in the carbon material (B) exceeds 99.0% by mass, the conductivity in the plane direction by the graphite particles becomes dominant, and the conductivity of the conductive film becomes dominant. It will reach a plateau.

When the content of graphite (B-1) in the carbon material (B) is 75.0% by mass or more, high conductivity can be easily exhibited without deteriorating the orientation of the graphite particles. ..

When the content of graphite (B-1) in the carbon material (B) is 80.0% by mass or more, the number of pinholes in the conductive film can be reduced and a good coating film can be easily formed.

When the content of graphite (B-1) in the carbon material (B) is 90.0 to 97.5% by mass, the carbon material (B-2) other than graphite has an appropriate blending amount and depends on the graphite particles. The vertical conductive network can be strengthened without impairing the high conductivity in the planar direction. As a result, very high conductivity can be exhibited. Further, when the content of graphite (B-1) in the carbon material (B) is less than 90.0% by mass, a coating film having less unevenness of the conductive film can be easily obtained.

(Carbon material other than graphite (B-2))
The carbon material (B-2) other than graphite is not particularly limited, and conventionally known materials can be used. Examples of the carbon material (B-2) include carbon black, conductive carbon fibers (carbon nanotubes, carbon nanofibers, carbon fibers), fullerene and the like. Among these, it is preferable to use carbon black as the carbon material (B-2) from the viewpoint of particle size and specific surface area. As the carbon material (B-2) other than graphite, one type may be used alone, or two or more types may be used in combination.

Examples of carbon black include furnace black, which is produced by continuously pyrolyzing a gas or liquid raw material in a reactor, especially acetylene black, which is made from ethylene heavy oil, and the raw material gas is burned to channel the flame. Examples thereof include channel black which is rapidly cooled and deposited on the bottom surface of steel, thermal black obtained by periodically repeating combustion and thermal decomposition using gas as a raw material, and acetylene black using acetylene gas as a raw material. Further, as the carbon black, carbon (black) that has been subjected to a normal oxidation treatment, hollow carbon, or the like can also be used.

Carbon oxidation treatment is generally performed to improve the dispersibility of carbon. Specifically, by treating carbon at a high temperature in the air or secondarily treating it with nitric acid, nitrogen dioxide, ozone, etc., it contains oxygen such as a phenol group, a quinone group, a carboxyl group, and a carbonyl group. This is a process for directly introducing (covalently bonding) a polar functional group onto the carbon surface. However, since the conductivity of carbon tends to decrease as the amount of the functional group introduced increases, it is preferable to use carbon that has not been oxidized.

As the specific surface area of carbon black increases, the contact points between the carbon black particles increase, which is advantageous for lowering the volume resistivity. Specifically, the specific surface area (BET) obtained from the amount of nitrogen adsorbed is preferably 20 m ² / g or more and 1500 m ² / g or less, more preferably 50 m ² / g or more and 1500 m ² / g or less, particularly preferably. It is desirable to use a material of 100 m ² / g or more and 1500 m ² / g or less. When the specific surface area of carbon black is 20 m ² / g or more, sufficient conductivity can be easily obtained, and when it is 1500 m ² / g or less, it is easily available as a commercially available material.

The particle size of carbon black is preferably 0.005 to 1 μm, more preferably 0.01 to 0.2 μm in terms of primary particle size. However, the primary particle diameter referred to here is an average of the particle diameters measured by an electron microscope or the like.

Examples of commercially available carbon black include Tokai Carbon's product names: Toka Black # 4300, # 4400, # 4500, # 5500, Degussa's product names: Printex L, and Colombian's Raven7000, 5750. 5250, 5000ULTRAIII, 5000ULTRA, ConductexSCULTRA, Conductex975ULTRA, PUERBLACK100, 115,205, Product names manufactured by Mitsubishi Chemical Co., Ltd .: # 2350, # 2400B, # 2600B, # 3050B, # 3030B, # 3230B, # 3350B, # 3350B, # 3350B , Cabot's product names: MONARCH1400, 1300, 900, VulcanXC-72R, BlackPearls2000, TIMCAL's product names: Ensaco250G, Ensaco260G, Ensaco350G, SuperP-Li and other furnace blacks;
Product name made by Lion: EC-300J, EC-600JD, etc. Ketchen Black;
Product names manufactured by Denki Kagaku Kogyo Co., Ltd .: Denka Black, Denka Black HS-100, FX-35 and other acetylene blacks can be mentioned. However, it is not limited to these carbon blacks. One type of carbon black may be used alone, or two or more types may be used in combination.

As the conductive carbon fiber, one obtained by firing from a raw material derived from petroleum is preferable, but one obtained by firing from a raw material derived from a plant can also be used. Further, the carbon nanotubes include a single-walled carbon nanotube in which a graphene sheet forms a tube having a diameter in a nanometer region, and a multi-walled carbon nanotube in which the graphene sheet is a multi-walled layer. Therefore, the diameter of the multi-walled carbon nanotubes is as large as 30 nm with respect to 0.7 to 2.0 nm of a typical single-walled carbon nanotube.

As commercially available conductive carbon fibers and carbon nanotubes, trade names manufactured by Showa Denko Co., Ltd .: vapor phase carbon fibers such as VGCF, and trade names manufactured by Meijo Nano Carbon Co., Ltd .: EC1.0, EC1.5, EC2.0, Examples thereof include single-walled carbon nanotubes such as EC1.5-P, trade names manufactured by CNano: FloTube9000, FloTube9100, FloTube9110, FloTube9200, trade names manufactured by Nanocyl: NC7000, and trade names manufactured by Knano: 100T.

(Curing agent (C))
Next, the curing agent (C) will be described.

The curing agent (C) is not particularly limited as long as it reacts with the reactive functional group contained in the binder resin (A). By curing the binder resin (A), the physical strength and chemical resistance of the resin are improved, and the durability of the conductive film is improved. Further, the conductivity is improved by the effect of the volume shrinkage of the conductive film at the time of curing.

Examples of the reactive functional group include, but are not limited to, a hydroxyl group, a phenolic hydroxyl group, a carboxyl group, an amino group, an acid anhydride group such as maleic anhydride, a thiol group and the like.

Examples of the curing agent (C) include an epoxy group-containing compound (C1), an isocyanate group-containing compound (C2), a blocked isocyanate group-containing compound (C3), an aziridine compound (C4), and a carbodiimide group-containing compound (C5). Examples thereof include a benzoxazine compound (C6), a phenol resin (C7), a maleimide compound (C8), a β-hydroxyalkylamide group-containing compound (C9), and a metal chelate (C10). The curing agent (C) may be used alone or in combination of two or more.

From the viewpoint of the durability of the conductive film, the epoxy group-containing compound (C1), the aziridine compound (C4) and the metal chelate (C10) are preferable as the curing agent (C), and the aziridine compound (C4) is preferable from the viewpoint of conductivity. ) And the metal chelate (C10) are more preferred, and the aziridine compound (C4) is particularly preferred.

The aziridine compound (C4) has very good reactivity with a binder resin containing a carboxyl group, a phenolic hydroxyl group, an acid anhydride and the like. Therefore, since the curing starts immediately after the conductive film dries, the curing shrinkage occurs remarkably, so that the fillers come into close contact with each other, and the conductivity is extremely improved as compared with the case where other curing agents are used.

Metal chelate (C10) is a general term for compounds in which a compound having a polydentate ligand in the molecule forms a complex so as to sandwich a metal ion. The metal chelate (C10) reacts with particles having functional groups on the surface such as carbon black and also functions as a dispersant, and suppresses irregular aggregation of the conductive fillers in the film forming process, thereby making the metal chelate uniform. Since a conductive path can be formed, excellent conductivity can be imparted.

-Epoxy group-containing compound (C1)
The epoxy group-containing compound (C1) is not particularly limited as long as it is a compound having an epoxy group in the molecule. However, as the epoxy group-containing compound (C1), a compound having an average of two or more epoxy groups in one molecule can be preferably used. As the epoxy-based compound (C1), for example, an epoxy resin such as a glycisyl ether type epoxy resin, a glycisylamine type epoxy resin, a glycidyl ester type epoxy resin, or a cyclic aliphatic (aliphatic) epoxy resin can be used. ..

Examples of the glycidyl ether type epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, and α-naphthol novolac. Type epoxy resin, bisphenol A type novolak type epoxy resin, dicyclopentadiene type epoxy resin, tetrabrom bisphenol A type epoxy resin, brominated phenol novolac type epoxy resin, tris (glycidyloxyphenyl) methane, or tetrakis (glycidyloxyphenyl) Etan and the like can be mentioned.

Examples of the glycidylamine type epoxy resin include tetraglycidyldiaminodiphenylmethane, triglycidylparaaminophenol, triglycidylmethaminophenol, tetraglycidylmethoxylylenediamine and the like.

Examples of the glycidyl ester type epoxy resin include diglycidyl phthalate, diglycidyl hexahydrophthalate, and diglycidyl tetrahydrophthalate.

Examples of the cyclic aliphatic (alicyclic) epoxy resin include epoxycyclohexylmethyl-epoxycyclohexanecarboxylate and bis (epoxycyclohexyl) adipate.

As the epoxy group-containing compound (C1), one of these compounds can be used alone or in combination of two or more. The epoxy group-containing compound (C1) includes bisphenol A type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, tris (glycidyloxyphenyl) methane, or tetrakis (glycidyloxyphenyl) ethane from the viewpoint of durability. It is preferable to use.

-Isocyanate group-containing compound (C2)
The isocyanate group-containing compound (C2) is not particularly limited as long as it is a compound having an isocyanate group in the molecule.

For example, examples of the isocyanate group-containing compound (C2) having one isocyanate group in one molecule include n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, benzyl isocyanate, (meth) acryloyloxyethyl isocyanate, and 1,1-bis [ (Meta) acryloyloxymethyl] ethyl isocyanate, vinyl isocyanate, allyl isocyanate, (meth) acryloyl isocyanate, isopropenyl-α, α-dimethylbenzyl isocyanate and the like can be mentioned.

In addition, 1,6-diisocyanatohexane, isophorone diisosocyanate, 4,4'-diphenylmethane diisocyanate, polypeptide diphenylmethane diisocyanate, xylylene diisocyanate, trilene 2,4-diisocyanate, toluene diisosocyanate, 2,4-diisocyanate Toluene, hexamethylene diisosocyanate, 4-methyl-m-phenylene diisosocyanate, naphthylene diisocyanate, paraphenylene diisocyanate, tetramethylxylylene diisocyanate, cyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, cyclohexyl diisocyanate, trizine diisocyanate, 2,2 , 4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, m-tetramethylxylylene diisocyanate, p-tetramethylxylylene diisocyanate, diisocyanate such as dimerate diisocyanate, hydroxyl group, carboxyl group , A compound obtained by reacting with an amide group-containing vinyl monomer in an equimolar amount can also be used as the isocyanate group-containing compound (C2).

Examples of the isocyanate group-containing compound (C2) having two isocyanate groups in one molecule include 1,3-phenylenediisocyanate, 4,4'-diphenyldiisocyanate, 1,4-phenylenediocyanate, and 4,4'-diphenylmethane. Diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidin diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanatebenzene, dianisidine diisocyanate, Aromatic diisocyanates such as 4,4'-diphenyl ether diisocyanate, 4,4', 4 "-triphenylmethane triisocyanate; trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, Aliphatic diisocyanates such as 2,3-butylenediocyanate, 1,3-butylenediocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate; ω, ω'-diisocyanate-1,3-dimethylbenzene, ω, Aromatic aliphatic diisocyanates such as ω'-diisocyanate-1,4-dimethylbenzene, ω, ω'-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate, etc. 3-Isocyanate Methyl-3,5,5-trimethylcyclohexylisocyanate [also known as isophoronediisocyanate], 1,3-cyclopentanediisocyanate, 1,3-cyclohexanediisocyanate, 1,4-cyclohexanediisocyanate, methyl-2,4- Alicyclic diisocyanates such as cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), 1,3-bis (isocyanatemethyl) cyclohexane, 1,4-bis (isocyanatemethyl) cyclohexane, etc. Can be mentioned.

Examples of the isocyanate group-containing compound having three isocyanate groups in one molecule include aliphatic polyisocyanates such as aromatic polyisocyanate and lysine triisocyanate, aromatic aliphatic polyisocyanates, and alicyclic polyisocyanates. Will be. In addition to this, the trimethylolpropane adduct body of diisocyanate described above, the biuret body reacted with water, and the trimer having an isocyanurate ring can be mentioned as examples.

-Blocked isocyanate group-containing compound (C3)
The blocked isocyanate group-containing compound (C3) is not particularly limited as long as it is a compound in which the isocyanate group in the isocyanate group-containing compound (C2) is protected (blocked) with a blocking agent. Examples of the blocking agent include ε-caprolactam, MEK oxime, cyclohexanone oxime, pyrazole, phenol and the like. In particular, the hexamethylene diisocyanate trimer having an isocyanurate ring and blocked with MEK oxime or pyrazole has not only storage stability but also adhesive strength to polyimide and copper when used in this conductive composition. It is very preferable because it has excellent solder heat resistance.

-Aziridine compound (C4)
The aziridine compound (C4) is not particularly limited as long as it is a compound containing an aziridine group in the molecule.

Examples of the aziridin compound (C4) include N, N'-diphenylmethane-4,4'-bis (1-aziridinecarbokisite) and N, N'-toluene-2,4-bis (1-aziridinecarbokisite). , Bisisophthaloyl-1- (2-methylaziridine), Tri-1-aziridinylphosphine oxide, N, N'-hexamethylene-1,6-bis (1-aziridinecarbokisite), trimethylolpropane- Tri-β-aziridinyl propionate, tetramethylolmethane-tri-β-aziridinyl propionate, tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, trimethylol Propanthris [3- (1-aziridinyl) propionate], trimethylolpropane tris [3- (1-aziridinyl) butyrate], trimethylolpropane tris [3- (1- (2-methyl) aziridinyl) propionate], trimethylol Propantris [3- (1-aziridinyl) -2-methylpropionate], 2,2'-bishydroxymethylbutanoltris [3- (1-aziridinyl) propionate], pentaerythritol tetra [3- (1-aziridinyl) ) Propionate], diphenylmethane-4,4-bis-N, N'-ethyleneurea, 1,6-hexamethylenebis-N, N'-ethyleneurea, 2,4,6- (triethyleneimino) -Syn- Examples thereof include triazine, bis [1- (2-ethyl) aziridinyl] benzene-1,3-carboxylic acid amide.

Among these, 2,2'-bishydroxymethylbutanoltris [3- (1-aziridinyl) propionate] is particularly preferably used in the present conductive composition because it provides good durability and conductivity. ..

-Carbodiimide group-containing compound (C5)
As the carbodiimide group-containing compound (C5), for example, the carbodilite series of Nisshinbo Holdings Co., Ltd. can be used. Among them, trade names: Carbodilite V-01, 03, 05, 07, 09 are preferable because they have excellent compatibility with organic solvents.

-Benzoxazine compound (C6)
Examples of the benzoxazine compound (C6) include "P-a", "P-alp", "P-ala", "B-ala" and Macromolecules, 34,7257 described in Macromolecules, 36,6010 (2003). (2001) "P-appe", "Bappe", "BA type benzoxazine", "FA type benzoxazine", "Bm type benzoxazine" manufactured by Shikoku Kasei Co., Ltd. are used. be able to.

・ Phenol resin (C7)
As the phenol resin (C7), for example, an addition compound of formaldehyde and a compound such as phenol, cresols, and bisphenols, or a partial condensate thereof can be used. More specifically, the phenol resin (C-7) includes a phenol resin, a cresol resin, a t-butylphenol resin, a dicyclopentadiencresol resin, a dicyclopentadienephenol resin, a xylylene-modified phenol resin, a tetrakisphenol resin, and a bisphenol A. Examples thereof include resin, resole-type resin of poly-p-vinylphenol resin, and novolak-type resin. In addition, a naphthol compound, a trisphenol compound, a phenol aralkyl resin and the like can also be used as the phenol resin (C7). Among these, the phenol resin resol type resin is extremely excellent in heat resistance and curability, and can be suitably used in the present conductive composition.

-Maleimide compound (C8)
The maleimide compound (C8) is not particularly limited as long as it has at least one maleimide group in the molecule. Examples of the maleimide compound (C8) include phenylmaleimide, 1-methyl-2,4-bismaleimidebenzene, N, N'-m-phenylene bismaleimide, N, N'-p-phenylene bismaleimide, N, N. '-4,4-biphenylene bismaleimide, N, N'-4,4- (3,3-dimethylbiphenylene) bismaleimide, N, N'-4,4- (3,3-dimethyldiphenylmethane) bismaleimide, N, N'-4,4- (3,3-diethyldiphenylmethane) bismaleimide, N, N'-4,4-diphenylmethane bismaleimide, N, N'-4,4-diphenylpropane bismaleimide, N, N '-4,4-diphenylether bismaleimide, N, N'-4,4-diphenylsulphon bismaleimide, 2,2-bis [4- (4-maleimidephenoxy) phenyl] propane, 2,2-bis [3- s-butyl-3,4- (4-maleimidephenoxy) phenyl] propane, 1,1-bis [4- (4-maleimidephenoxy) phenyl] decane, 4,4'-cyclohexylidene-bis [1-( 4-maleimide phenoxy) phenoxy] -2-cyclohexylbenzene, 2,2-bis [4- (4-maleimide phenoxy) phenyl] hexafluoropropane and the like can be mentioned.

-Β-Hydroxyalkylamide group-containing compound (C9)
Various β-hydroxyalkylamide group-containing compounds (C9) include, for example, N, N, N', N'-tetrakis (hydroxyethyl) adipamide (manufactured by Ems-Chemie, trade name: Primid XL-552). Compounds can be used.

-Metal chelate (C10)
Examples of the metal chelate (C10) include a chelate compound in which a metal alkoxide is reacted with a chelating agent such as β-diketone or ketoester (ethyl acetoacetate or the like). More specifically, examples of the metal chelate (C10) include aluminum chelate, zirconium chelate, titanium chelate and the like.

Examples of the aluminum chelate include aluminum monoacetylacetonate bis (ethylacetate acetate), aluminum ethylacetate acetate diisopropyrate, aluminum tris (acetylacetone), aluminum tris (ethylacetacetate), aluminum isopropyrate and the like. ..

Examples of the zirconium chelate include zirconium tetraacetylacetonate and zirconium tributoxymonoacetylacetonate.

Examples of the titanium chelate include titanium diisopropoxybis (acetylacetoneate), titaniumtetraacetylacetonate, and titaniumdiisopropoxybis (ethylacetoacetate).

From the viewpoint of the conductivity of the conductive film, it is preferable to use an aluminum chelate as the metal chelate (C10). Aluminum chelates have very good reactivity with binder resins containing carboxyl groups, phenolic hydroxyl groups, acid anhydrides, etc., and have a good effect on the dispersibility of carbon materials, so they are better than when other metal chelates are used. Also, the conductivity is extremely improved. Among them, aluminum monoacetylacetonate bis (ethylacetoacetate) is particularly preferable.

The amount of the curing agent (C) used may be determined in consideration of the use of the present conductive composition and the like, and is not particularly limited. However, the content of the curing agent (C) is preferably 0.5 to 20% by mass with respect to 100% by mass of the binder resin (A). When the content of the curing agent (C) is 0.5% or more, the crosslinkability becomes good, both the conductivity and the durability tend to improve, and when it is 20% or less, the pot life of the ink is better. Will be.

When a metal chelate (C10) and another curing agent are used in combination as the curing agent (C), the mass ratio (metal chelate / other curing agent) may be 1/99 to 60/40. It is preferable to blend in 10/90 to 30/70, and more preferably.

<Solvent (D)>
Next, the solvent (D) arbitrarily added to the present conductive composition will be described. When the binder resin (A), the carbon material (B), and the curing agent (C) in the conductive composition are uniformly mixed, the solvent (D) can be appropriately used. Examples of such a solvent (D) include an organic solvent and water.

Examples of the organic solvent include alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol methyl ether and diethylene glycol methyl ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, tetrahydrofuran, dioxane and ethylene glycol dimethyl ether. A conductive composition from ethers such as diethylene glycol dimethyl ether, hydrocarbons such as hexane, heptane and octane, aromatics such as benzene, toluene, xylene and cumene, and esters such as ethyl acetate and butyl acetate. It can be appropriately selected and used according to the composition. Further, the solvent (D) may be used alone or in combination of two or more.

When a printing coating method such as screen printing, which requires the conductive composition to have a viscosity of a certain level or higher, is adopted, the viscosity of the organic solvent at 25 ° C. is preferably in the range of 30 mPa · s to 75,000 mPa · s. When the viscosity of the organic solvent is 30 mPa · s or more, the resin content is suitable for exhibiting high conductivity, and good dispersibility of the viscous and conductive carbon material suitable for coating can be easily obtained. , Excellent coatability can be obtained. When the viscosity of the organic solvent is 75,000 mPa · s or less, the dispersibility of the carbon material becomes better. Examples of the organic solvent include tarpineol, dihydroterpineol, 2,4-diethyl-1,5-pentanediol, 1,3-butylene glycol, and isobornylcyclohexanol. These high-viscosity solvents may be used alone or in combination of two or more. Further, these high-viscosity solvents and low-viscosity solvents such as methyl ethyl ketone, toluene, and isopropyl alcohol having a viscosity at 25 ° C. of less than 30 mPa · s can also be used in combination.

<Other ingredients>
Next, other components will be described. The present conductive composition may contain, if necessary, an ultraviolet absorber, an ultraviolet stabilizer, a radical catching agent, a filler, a thixotropic agent, an antioxidant, an antioxidant, as long as the effect of the present invention is not impaired. Antistatic agents, flame retardants, thermal conductivity improvers, plasticizers, anti-sag agents, antifouling agents, preservatives, bactericides, defoamers, leveling agents, anti-blocking agents, thickeners, pigment dispersants, silanes. Various additives such as a coupling agent may be added.

<Distributor / Mixer>
As an apparatus used for obtaining the present conductive composition from each of the above components, a disperser, a mixer or the like usually used for pigment dispersion or the like can be used.

Examples of the above-mentioned device include mixers such as a dispenser, a homomixer, or a planetary mixer; homogenizers such as "Clairemix" manufactured by M-Technique or "Fillmix" manufactured by PRIMIX; and a paint conditioner (manufactured by Red Devil). ), Ball mill, sand mill ("Dyno mill" manufactured by Symmar Enterprises, etc.), attritor, pearl mill ("DCP mill" manufactured by Eirich, etc.), or media type disperser such as Coball mill; wet jet mill ("Dyno mill" manufactured by Genus). Medialess disperser such as "Genus PY", "Starburst" manufactured by Sugino Machine Limited, "Nanomizer" manufactured by Nanomizer, "Claire SS-5" manufactured by M-Technique, or "MICROS" manufactured by Nara Machinery; or , Other roll mills, etc., but are not limited to these.

For example, when using a media type disperser, a method using a disperser in which the agitator and vessel are made of ceramic or resin, or a disperser in which the surface of the metal agitator and vessel is treated with tungsten carbide spraying or resin coating. It is preferable to use. As the medium, it is preferable to use glass beads, zirconia beads, or ceramic beads such as alumina beads. As the dispersive device, only one type may be used, or a plurality of types of devices may be used in combination.

<Conductor>
The conductive film of the present invention (hereinafter, may be referred to as the present conductive film) is a conductive film formed from the present conductive composition on a (sheet-like) substrate, in other words, the present conductive composition is formed into a film. It has a conductive film made of.

(Sheet-like base material)
The shape of the sheet-like base material used for forming the conductive film is not particularly limited, but an insulating resin film is preferable, and one suitable for various uses can be appropriately selected.

Examples of the material of the sheet-like base material include PET (polyethylene terephthalate), PEN (polyethylene naphthalate), polyimide, polyvinyl chloride, polyamide, nylon, OPP (stretched polypropylene), CPP (unstretched polypropylene) and the like. .. However, it is not limited to these.

As the shape of the sheet-like base material, a film on a flat plate is usually used, but a roughened surface, a primer-treated one, a perforated one, and a mesh-like one can also be used. ..

The method of applying the conductive composition on the sheet-like substrate is not particularly limited, and a known method can be appropriately used.

Specific examples of the coating method include a die coating method, a dip coating method, a roll coating method, a doctor coating method, a knife coating method, a spray coating method, a gravure coating method, a screen printing method, an electrostatic coating method, and the like. Can be mentioned. As the drying method after coating, for example, a neglected drying, a blower dryer, a warm air dryer, an infrared heater, a far infrared heater, and the like can be used, but the drying method is not particularly limited thereto.

Further, after coating, rolling processing may be performed by a lithographic press, a calendar roll, or the like, or in order to soften the conductive film and make it easier to press, rolling processing may be performed while heating. The thickness of the conductive film is usually 0.1 μm or more and 1 mm or less, preferably 1 μm or more and 200 μm or less.

(Volume resistivity of conductive film)
The volume resistivity of this conductive film is preferably less than 1.0 × 10 ⁻² Ω · cm. Since the volume resistivity is less than 1.0 × 10 ⁻² Ω · cm, it can be suitably used as a battery electrode, a current collector, a battery, wiring of an electronic device, and the like.

<Non-contact media>
The non-contact type media (non-contact type information recording medium) (hereinafter, may be referred to as the present non-contact type media) of the present invention is a non-contact type medium loaded with a conductive circuit and an IC chip, and the conductive circuit is a non-contact type medium. , Formed using the present conductive composition described above.

(Conductive circuit)
The conductive circuit used in the non-contact media can be obtained by printing the conductive composition on one side or both sides of a base material such as paper or plastic by a normal printing method depending on the intended use. It is a thing (printed matter).

Examples of the printing method include screen printing, rotary screen printing, flexo printing, gravure printing, gravure offset printing, offset printing, letterpress printing, inkjet, and the like.

As the paper base material, various processed papers such as coated paper, uncoated paper, synthetic paper, polyethylene coated paper, impregnated paper, water resistant processed paper, insulating processed paper, and stretch processed paper can be used. Among these, it is preferable to use coated paper or processed paper as the paper base material from the viewpoint of obtaining a stable resistance value as a non-contact medium. In the case of coated paper, the one with higher smoothness is preferable.

In addition, as the plastic base material, from plastics used as ordinary tags and cards such as polyester, polyethylene, polypropylene, cellophane, vinyl chloride, vinylidene chloride, polystyrene, vinyl alcohol, ethylene-vinyl alcohol, nylon, polyimide, polycarbonate, etc. Substrate can be used.

By using this conductive composition (conductive ink), a conductive circuit can be formed by a normal printing method, so it is possible to design using existing equipment. That is, it is possible to print and form the conductive circuit as it is after performing normal printing for enhancing the design of the non-contact medium such as a pattern. Therefore, the circuit formation using the present conductive composition is far superior in productivity, initial investment cost, and running cost as compared with the circuit formation method conventionally performed by the etching method or the transfer method. There is.

In the process before printing and forming the conductive circuit, an anchor coating agent or various varnishes may be applied to the base material for the purpose of improving the adhesion to the base material. Further, after printing the conductive circuit, an overprint varnish, various coating agents, or the like may be applied for the purpose of protecting the circuit. As these various varnishes and coating agents, either a normal heat-drying type or an active energy ray-curing type can be used.

Alternatively, a non-contact medium can be obtained by applying an adhesive on a conductive circuit and adhering a paper base material or a plastic film on which a pattern or the like is printed as it is, or laminating by melt extrusion of plastic or the like. Of course, a base material to which an adhesive or an adhesive has been applied in advance can also be used.

The conductive circuit manufactured by the above method is loaded on the base material together with the IC module, and a non-contact type medium can be obtained. The base material holds the conductive circuit and the IC chip, and paper, film, or the like similar to the base material of the conductive circuit can be used. Further, the IC chip stores, stores, and calculates data. Non-contact media is an individual using radio waves as an RFID (Radio Frequency Identification), contactless IC card, contactless IC tag, data carrier (recording medium), wireless card, and a reader or writer. It is used to identify and send and receive data. Its uses include ID management and history management of toll collection systems, and location management of road usage status management systems, cargo, and baggage tracking / management systems.

(Volume resistivity of conductive circuit)
The volume resistivity of the conductive circuit in this non-contact media is preferably less than 5.0 × 10 ⁻² Ω · cm. When the volume resistivity is less than 5.0 × 10 ⁻² Ω · cm, it can be suitably used as a non-contact type medium. The lower the volume resistivity, the higher the conductivity is exhibited even in a thin film. Therefore, considering the material cost, productivity, and performance as a non-contact medium, the lower the volume resistivity is, the more preferable.

Hereinafter, the present invention will be described in more detail by way of examples, but the following examples do not limit the scope of rights of the present invention at all. In Examples and Comparative Examples, "parts" means "parts by mass", "Mw" means "weight average molecular weight", and "Tg" means "glass transition temperature" unless otherwise specified.

<Synthesis of binder resin A-1>
The following materials were placed in a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen introduction tube, and reacted at 90 ° C. for 3 hours in a nitrogen atmosphere.
-Polyester polyol obtained from terephthalic acid, adipic acid and 3-methyl-1,5-pentanediol (manufactured by Kuraray Co., Ltd., trade name: "Kuraray polyol P-2011", Mn = 2011) 455.5 parts,
16.5 parts of dimethylolbutanoic acid,
・ Isophorone diisocyanate 105.2 parts,
-140 parts of toluene.
Subsequently, 360 parts of toluene was added to this reaction solution to obtain a urethane prepolymer solution having an isocyanate group.

Next, 19.9 parts of isophorone diamine, 0.63 parts of di-n-butylamine, 294.5 parts of 2-propanol, and 335.5 parts of toluene were separately mixed. To the obtained mixture, 969.5 parts of the urethane prepolymer solution prepared above was added and reacted at 50 ° C. for 3 hours, and then further reacted at 70 ° C. for 2 hours. Subsequently, the obtained reaction solution was diluted with 126 parts of toluene and 54 parts of 2-propanol to obtain a solution of the binder resin A-1 (polyurethane resin). The obtained binder resin A-1 has a Mw of 61,000, an acid value of 10 mgKOH / g, and a polyamino compound and a reaction terminator for free isocyanate groups at both ends of the urethane prepolymer. The total equivalent of the amino groups in it was 0.98.

<Synthesis of binder resin A-2>
The following materials were placed in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen introduction tube, an introduction tube, and a thermometer, and the mixture was stirred until the heat generation temperature became constant.
-As a polybasic acid compound, Pripol 1009 156.2 g,
-5.5 g of 5-hydroxyisophthalic acid,
-As a polyamine compound, preamine 1074 146.4 g,
-Ion-exchanged water 100 g.
Then, when the temperature of the reaction solution stabilizes, the temperature is raised to 110 ° C., and after confirming the outflow of water, the temperature is raised to 120 ° C. after 30 minutes, and then the temperature is raised by 10 ° C. every 30 minutes. The dehydration reaction continued. Then, when the temperature of the reaction solution reached 230 ° C., the reaction was continued at the same temperature for 3 hours and kept under a vacuum of about 2 kPa for 1 hour to lower the temperature. Finally, an antioxidant was added to obtain a binder resin A-2 (polyamide resin). The obtained binder resin A-2 has a weight average molecular weight of 24,000, an acid value of 13.2 mgKOH / g, a hydroxyl value of 5.5 mgKOH / g, and a glass transition temperature of −32 ° C. there were.

The resin was evaluated as follows.

<Measurement method of weight average molecular weight (Mw)>
For the measurement of Mw, GPC (gel permeation chromatography) trade name: "HPC-8020" manufactured by Tosoh Corporation was used. GPC is a liquid chromatography in which a substance dissolved in a solvent (THF: tetrahydrofuran) is separated and quantified according to the difference in molecular size. For the measurement, two columns were connected in series with the product name: "LF-604" (manufactured by Showa Denko KK: GPC column for rapid analysis: 6 mm ID x 150 mm size), and the flow rate was 0.6 ml / min and the column temperature. The measurement was performed under the condition of 40 ° C., and the weight average molecular weight (Mw) was determined in terms of polystyrene.

<Measurement method of acid value>
(Measurement of acid value)
Approximately 1 g of the sample (resin) was precisely weighed into a stoppered Erlenmeyer flask, and 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution was added and dissolved. Phenolphthalein test solution was added to this as an indicator and held for 30 seconds. Then, it was titrated with 0.1N alcoholic potassium hydroxide solution until the solution became light red.

(Calculation of acid value)
The acid value was determined by the following formula (1) (unit: mgKOH / g).
Equation (1)
Acid value (mgKOH / g) = (5.611 × a × F) / S
however,
S: Sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
F: The titer of a 0.1N alcoholic potassium hydroxide solution was used.

<Measurement method of hydroxyl value>
The hydroxyl value is the amount of hydroxyl group contained in 1 g of the hydroxyl group-containing resin expressed by the amount of potassium hydroxide (mg) required to neutralize acetic acid bonded to the hydroxyl group when the hydroxyl group is acetylated. Is. The hydroxyl value was measured according to JIS K0070. When calculating the hydroxyl value, the acid value was taken into consideration as shown in the following formula (2).

(Measurement of hydroxyl value)
Approximately 1 g of the sample (resin) was precisely weighed into a stoppered Erlenmeyer flask, and 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution was added and dissolved. Further, exactly 5 ml of an acetylating agent (a solution in which 25 g of acetic anhydride was dissolved in pyridine to make a volume of 100 ml) was added, and the mixture was stirred for about 1 hour. Phenolphthalein test solution was added to this as an indicator and lasted for 30 seconds. Then, it was titrated with 0.1N alcoholic potassium hydroxide solution until the solution became light red.

(Calculation of hydroxyl value)
The hydroxyl value was determined by the following formula (2) (unit: mgKOH / g).
Equation (2)
Hydroxy group value (mgKOH / g) = [{(ba) × F × 28.05} / S] + D
however,
S: Sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
b: Consumption (ml) of 0.1N alcoholic potassium hydroxide solution in the blank experiment
F: Titer of 0.1N alcoholic potassium hydroxide solution D: Acid value (mgKOH / g)
And said.

<Measurement method of glass transition temperature>
The binder resin from which the solvent was dried and removed was measured by using "DSC-1" manufactured by METTLER TOLEDO Co., Ltd. and raising the temperature from -80 to 150 ° C. at 2 ° C./min.

<Adjustment of binder resin>
The binder resin used in Examples and Comparative Examples described later was adjusted to a solution having a solid content of 20% using the solvent shown below. The composition ratio of the mixed solvent is described as a mass ratio.
-Solution of binder resin A-1-1:
The solution of the binder resin A-1 was diluted with toluene / methyl ethyl ketone / 2-propanol (1/1/1) to obtain a solution of the binder resin A-1-1.
-Solution of binder resin A-2-1:
Binder resin A-2 was diluted with toluene / 2-propanol (2/1) to obtain a solution of binder resin A-2-1.
-Solution of binder resin A-3-1:
Binder resin A-3: Byron UR3500 (trade name, manufactured by Toyobo Co., Ltd., polyurethane resin) was diluted with toluene / methyl ethyl ketone (1/1) to obtain a solution of the binder resin A-3-1.
-Solution of binder resin A-4-1:
Binder resin A-4: Byron GK130 (trade name, manufactured by Toyobo Co., Ltd., polyester resin) was diluted with toluene / methyl ethyl ketone (1/1) to obtain a solution of the binder resin A-4-1.

<Adjustment of curing agent>
The curing agent used in Examples and Comparative Examples described later was adjusted to a solution having a solid content of 50% using the solvent shown below. The composition ratio of the mixed solvent is described as a mass ratio. As for the curing agent C-3 described later, a commercially available product having a solid content concentration of 50% by mass was used as it was.
-Solution of curing agent C-1-1:
The curing agent C-1 (aziridin compound Chemitite PZ-33 (trade name, manufactured by Nippon Shokubai Co., Ltd.)) was diluted with toluene to obtain a solution of the curing agent C-1-1.
-Solution of curing agent C-2-1:
The curing agent C-2 (epoxy compound TETRAD-X (trade name, manufactured by Mitsubishi Gas Chemical Company, Inc.)) was diluted with toluene to obtain a solution of the curing agent C-2-1.
-Solution of curing agent C-4-1: A solution of curing agent C-4-1 was obtained by diluting the curing agent C-4 (isocyanate compound Takenate D-110N: manufactured by Mitsui Chemicals, Inc.) with ethyl acetate. ..
-Solution of curing agent C-5-1:
Hardener C-5 {Aluminum chelate Aluminum monoacetylacetonate bis (ethylacetate acetate) = Aluminum chelate D (trade name), manufactured by Kawaken Fine Chemical Co., Ltd.} is diluted with toluene to form a solution of hardener C-5-1. Got
-Solution of curing agent C-6-1:
The curing agent C-6 (titanium chelate titanium tetraacetylacetonate = Organix TC-401 (trade name), manufactured by Matsumoto Fine Chemical Co., Ltd.) was diluted with toluene to obtain a solution of the curing agent C-6-1.
-Solution of curing agent C-7-1:
Hardener C-7 {Titanium chelate Titanium diisopropoxybis (acetylacetone) = Olgatics TC-100 (trade name), manufactured by Matsumoto Fine Chemical Co., Ltd.} is diluted with toluene to form a solution of hardener C-7-1. Got
-Solution of curing agent C-8-1:
A solution of the curing agent C-8-1 was obtained by diluting the curing agent C-8 (zirconium chelate zirconium tetraacetylacetonate = Olgatics ZC-150 (trade name), manufactured by Matsumoto Fine Chemical Co., Ltd.) with toluene.

<Conductive composition, conductive film and conductive circuit>
[Example 1]
(Preparation of conductive composition)
The following materials were placed in a mixer and mixed, and then placed in a sand mill for dispersion.
・ Binder resin:
120 parts of A-1-1 solution (24 parts of resin solid content),
-Conductive carbon material:
B-1-1: Scale graphite CPB (manufactured by Nippon Graphite Co., Ltd.) 70 copies,
・ Carbon materials other than graphite:
B-2-1: Ketjen Black EC-300J (trade name, manufactured by Lion Specialty Chemicals) 6 copies,
·solvent:
Toluene / Methylethylketone / 2-propanol (1/1/1) 204 parts.
Then, 0.4 part (curing agent solid content 0.2 part) of the solution of C-1-1 was added as a curing agent to obtain a conductive composition (1).

(Preparation of conductive film)
The obtained conductive composition (1) was applied to a PEN film having a thickness of 125 μm as a sheet-like substrate by using a doctor blade, and then dried by heating to adjust the thickness of the conductive film to 60 μm. .. Finally, the coating film was cured in an environment of 150 ° C. The conductive carbon material contained in the conductive film was 76% by mass.
The obtained conductive film was evaluated by the following method. The evaluation results are shown in Table 6.

(Volume resistivity of conductive film)
The volume resistivity of the conductive film was measured by the 4-terminal method (JIS-K7194) using Loresta GP (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), and was determined based on the following evaluation criteria. The lower the volume resistivity of the conductive film, the higher the conductivity of the conductive film, and the better the result. The evaluation results are shown in Table 6.
-Evaluation standard 8: "Volume resistivity is less than 3.0 x 10 ^-3 Ω · cm"
7: "Volume resistivity is 3.0 x 10 ^-3 Ω · cm or more, 3.5 x 10 ^-3 Ω · cm or less"
6: "Volume resistivity is 3.5 x 10 ^-3 Ω · cm or more and 4.0 x 10 ^-3 Ω · cm or less"
5: "Volume resistivity is 4.0 x 10 ^-3 Ω cm or more, 5.0 x 10 ^-3 Ω cm or less"
4: "Volume resistivity is 5.0 x 10 ^-3 Ω · cm or more, 1.0 x 10 ^-2 Ω · cm or less"
3: "Volume resistivity is 1.0 x 10 ^-2 Ω · cm or more, 5.0 x 10 ^-2 Ω · cm or less"
2: "Volume resistivity is 5.0 x 10 ^-2 Ω · cm or more, 1.0 x 10 ^-1 Ω · cm or less"
1: "Volume resistivity is 1.0 x 10 ^-1 Ω · cm or more"

(Adhesion of conductive film)
The conductive film produced above was cut into 6 grids in each of the vertical and horizontal directions at intervals of 2 mm from the surface of the conductive film to the depth reaching the substrate by using a knife. An adhesive tape was attached to this notch and immediately peeled off, and the degree of the conductive film falling off was visually judged based on the following evaluation criteria. The evaluation results are shown in Table 6.
・ Evaluation standard 4: "No peeling"
3: "Slight peeling"
2: "About half peeling"
1: "Peeling in most parts"

(Manufacturing of conductive circuit)
The conductive composition (1) was applied onto a PEN (polyethylene naphthalate) film having a thickness of 125 μm using a doctor blade, and then dried by heating. The dry film thickness was adjusted to 5 μm. Finally, the coating film was cured under a temperature condition of 150 ° C. to obtain a conductive circuit (10 cm × 10 cm coating film).

(Volume resistivity of conductive circuit)
The volume resistivity of the conductive circuit was measured by the 4-terminal method (JIS-K7194) using Loresta GP (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), and was determined based on the following evaluation criteria. The lower the volume resistivity of the conductive circuit, the higher the conductivity of the conductive circuit, and the better the result. The evaluation results are shown in Table 6.
-Evaluation standard 8: "Volume resistivity is less than 3.0 x 10 ^-3 Ω · cm"
7: "Volume resistivity is 3.0 x 10 ^-3 Ω · cm or more, 3.5 x 10 ^-3 Ω · cm or less"
6: "Volume resistivity is 3.5 x 10 ^-3 Ω · cm or more and 4.0 x 10 ^-3 Ω · cm or less"
5: "Volume resistivity is 4.0 x 10 ^-3 Ω cm or more, 5.0 x 10 ^-3 Ω cm or less"
4: "Volume resistivity is 5.0 x 10 ^-3 Ω · cm or more, 1.0 x 10 ^-2 Ω · cm or less"
3: "Volume resistivity is 1.0 x 10 ^-2 Ω · cm or more, 5.0 x 10 ^-2 Ω · cm or less"
2: "Volume resistivity is 5.0 x 10 ^-2 Ω · cm or more, 1.0 x 10 ^-1 Ω · cm or less"
1: "Volume resistivity is 1.0 x 10 ^-1 Ω · cm or more"

(Adhesion of conductive circuit)
In the conductive circuit produced above, a knife was used to make cuts from the surface of the conductive circuit to the depth reaching the base material in 6 grids in each of the vertical and horizontal directions at intervals of 2 mm. An adhesive tape was attached to this notch and immediately peeled off, and the degree of dropout of the conductive circuit was visually judged based on the following evaluation criteria. The evaluation results are shown in Table 6.
・ Evaluation standard 4: "No peeling"
3: "Slight peeling"
2: "About half peeling"
1: "Peeling in most parts"

<Evaluation of coatability>
The coatability of the conductive composition (1) was evaluated as follows using the conductive film and the conductive circuit produced above. That is, the produced conductive film and conductive circuit are visually observed, respectively, and coating unevenness (unevenness: evaluated by the shade of the coated surface) and pinhole (evaluated by the presence or absence of defects to which the conductive film / conductive circuit is not applied). Was determined based on the following criteria. The evaluation results are shown in Table 6.

(village)
3: The shade of the conductive film / conductive circuit is not confirmed.
2: There are 1 to 3 shades of the conductive film / conductive circuit, but it is an extremely minute region.
1: The shading of the conductive film / conductive circuit is confirmed at four or more places, or one or more of the shading stripes having a length of 5 mm or more are confirmed.

(Pinhole)
◯: No pinhole is confirmed.
Δ: There are 1 to 3 pinholes, but they are extremely small.
X: Four or more pinholes are confirmed, or one or more pinholes having a diameter of 1 mm or more are confirmed.

<Durability evaluation>
The superiority or inferiority of the durability of the conductive film and the conductive circuit produced by using the conductive composition (1) was evaluated based on the following criteria based on the rate of increase in volume resistivity after the moisture resistance heat test. The evaluation results are shown in Table 6.
The method is shown below.
First, the prepared coating film (conductive film / conductive circuit) was put into a small environmental tester (Espec Co., Ltd .: model number SH-661), left at a temperature of 60 ° C. and a relative humidity of 90% for 5000 hours, and then placed in a room temperature environment. After returning, the volume resistivity was measured using the method described above.
-Evaluation standard 3: The rate of increase in volume resistivity is less than 10%,
2: The rate of increase in volume resistivity is 10% or more and less than 20%,
1: The rate of increase in volume resistivity is 20% or more.

(Non-contact media characteristics of conductive circuit)
A flexo plate (DSF version: manufactured by DuPont) having a conductor pattern was attached to the second unit of the CI type 6-color flexo printing machine SOLOFLEX (manufactured by Windmoeller & Holescher KG). Then, the conductive composition (1) was sequentially printed on the PEN film (125 μm) at a speed of 70 m / min. The film thickness of the printed matter is measured with a digital micro film thickness meter (manufactured by Nikon Corporation, trade name: MH15M), the printing conditions are appropriately adjusted so that the average film thickness is 5 to 10 μm, and after heating and drying, non-contact is performed. A conductive circuit for evaluating media characteristics was obtained. An IC chip manufactured by Impinge Co., Ltd. was mounted on the obtained conductive circuit to produce a non-contact type media.
Next, the possibility of communication was confirmed using "Fixed UHF band RFID reader / writer Speedway Revolution R420 (trade name)" manufactured by Impingi. The evaluation results are shown in Table 6.
Y: Readable N: Unreadable

[Examples 2 to 81, Comparative Examples 1 to 20]
The conductive compositions (2) to (81) and (a) to (t) were obtained in the same manner as in the conductive composition (1) at the composition ratios shown in Tables 1 to 5. The obtained conductive compositions (2) to (81) and (a) to (t) were used for evaluation in the same manner as in Example 1. The evaluation results are shown in Tables 6 to 10.
In Example 14, since the type of the binder resin is different from that of Example 1, the diluting solvent at the time of producing the conductive composition was toluene / 2-propanol (2/1).
In Examples 15 to 17, since the type of the binder resin is different from that in Example 1, the diluting solvent for producing the conductive composition was toluene / methyl ethyl ketone (1/1).
In Examples 36, 37, 38, 40, 76, 77, 78 and 80, two kinds of curing agents were used in combination and added at the same timing. In Example 36, C-1 / C-2 (= 0.85 / 16.15) contained 0.85% of C-1 in solid content with respect to 100 parts by mass of resin solid content, and C-2. It means that 16.15% was added, and the same applies to Examples 37, 38, 40, 76, 77, 78 and 80.

The materials used in the examples are shown below.

<Binder resin (A)>
-A-1: Polyurethane resin (acid value: 10 mgKOH / g)
A-2: Polyamide resin (acid value 13.2 mgKOH / g, hydroxyl value 5.5 mgKOH / g)
-A-3: Polyurethane resin Byron UR3500 (trade name, acid value: 35 mgKOH / g, hydroxyl value: 10 mgKOH / g, manufactured by Toyobo Co., Ltd.)
-A-4: Polyester resin Byron GK130 (trade name, hydroxyl value: 19 mgKOH / g, manufactured by Toyobo Co., Ltd.)

<Carbon material (B)>
(Graphite (B-1)>
B-1-1: Scale graphite CPB (trade name, manufactured by Nippon Graphite Co., Ltd.) Average particle size 20 μm (catalog)
B-1-2: Thinned graphite UP-20 (trade name, manufactured by Nippon Graphite Co., Ltd.) Average particle size 20 μm (catalog)
B-1-3: Expanded graphite GR15 (trade name, manufactured by Nippon Graphite Co., Ltd.) Average particle size 15 μm (catalog)
B-1-4: Spheroidal graphite CGB-50 (trade name, manufactured by Nippon Graphite Co., Ltd.) Average particle size 50 μm (catalog)
B-1-5: Artificial graphite PAG-5 (trade name, manufactured by Nippon Graphite Co., Ltd.) Average particle size 30 μm (catalog)

(Carbon material other than graphite (B-2)>
・ B-2-1: Ketjen Black EC-300J (trade name, manufactured by Lion Specialty Chemicals Co., Ltd.)
・ B-2-2: Ketjen Black EC-600JD (trade name, manufactured by Lion Specialty Chemicals Co., Ltd.)
・ B-2-3: Furness Black # 3050B (trade name, manufactured by Mitsubishi Chemical Corporation)
・ B-2-4: Denka Black HS-100 (trade name, manufactured by Denki Kagaku Kogyo Co., Ltd.)
-B-2-5: Carbon nanotube VGCF-H (trade name, manufactured by Showa Denko KK)

<Curing agent (C)>
C-1: Aziridine compound Chemitite PZ-33 (trade name, solid content 100% by mass, manufactured by Nippon Shokubai Co., Ltd.)
-C-2: Epoxy compound TETRAD-X (trade name, solid content 100% by mass, manufactured by Mitsubishi Chemical Gas Chemical Co., Ltd.)
C-3: Carbodiimide compound Carbodilite V-03 (trade name, solid content 50% by mass, manufactured by Nisshinbo Chemical Co., Ltd.)
C-4: Isocyanate compound Takenate D-110N (trade name, solid content 75% by mass, manufactured by Mitsui Chemicals, Inc.)
-C-5: Aluminum chelate Aluminum chelate D (trade name, solid content 100% by mass, manufactured by Kawaken Fine Chemical Co., Ltd.)
-C-6: Titanium chelate Organix TC-401 (trade name, solid content 65% by mass, manufactured by Matsumoto Fine Chemical Co., Ltd.)
-C-7: Titanium chelate Organix TC-100 (trade name, solid content 75% by mass, manufactured by Matsumoto Fine Chemical Co., Ltd.)
C-8: Zirconium chelate Organix ZC-150 (trade name, solid content 100% by mass, manufactured by Matsumoto Fine Chemical Co., Ltd.)

As shown in Tables 6 to 9, in the conductive film and the conductive circuit using the present conductive composition, by using the curing agent (C), the adhesion, the conductivity and the durability are improved more than before. I was able to achieve both.
In Comparative Examples 6, 8 and 13, the amount of the binder resin and the ratio of the carbon material other than graphite and graphite are within an appropriate range, but the binder resin is not cured because the curing agent is not added. The result is insufficient durability. In Examples 36, 37, 38, 76, 77, and 78, two types of curing agents are used in combination, and the reaction occurs at a wider temperature range than when used alone. Therefore, Examples 39, which contain only one type of curing agent. It is more stable than 79 and can exhibit very high conductivity.
Further, as for the non-contact type media characteristics, since the resistance value of the conductive circuit was low in Examples 1 to 81, communication could be confirmed. On the other hand, in Comparative Examples 3 to 6, 8, 9, 11, 12, 14 to 18, and 20, communication could not be confirmed because the resistance values were high. Further, in Comparative Examples 1, 2, 7, 10 and 19, since the filling amount of the conductive particles was large and the resistance value was low, transmission and reception were possible, but on the other hand, the resin content was small and the adhesion to the substrate was extremely low. Because of its badness, its practicality as a non-contact medium was poor. Further, although Comparative Example 13 was able to transmit and receive, the durability of the conductive circuit was low, and its practicality as a non-contact medium was poor.

As described above, in the conductive composition containing the binder resin, the carbon material, and the curing agent, the blending ratio of the carbon material in the conductive composition and the mixing ratio of graphite and the carbon material other than graphite are selectively selected. It was found that by controlling the graphite material, it is possible to form an excellent conductive network between carbon materials, and to exhibit excellent conductivity, adhesion and durability.

Since the conductive composition of the present invention has extremely excellent conductivity as a carbon material, it can be applied to a wide range of application fields including RFID antennas, wiring materials, flat heating elements, and electrode materials.

This application claims priority based on Japanese application Japanese Patent Application No. 2020-182741 filed on October 30, 2020, and incorporates all of its disclosures here.

Claims

A conductive composition containing a binder resin (A), a carbon material (B), and a curing agent (C).
The carbon material (B) contains graphite (B-1) and a carbon material other than graphite (B-2).
The content of the carbon material (B) is 65 to 85% by mass in 100% by mass of the solid content of the conductive composition.
A conductive composition having a graphite (B-1) content of 70.0 to 99.0% by mass in 100% by mass of the carbon material (B).
The conductive composition according to claim 1, wherein the content of the curing agent (C) is 0.5 to 20% by mass with respect to 100% by mass of the binder resin (A).
The conductive composition according to claim 1 or 2, wherein the content of graphite (B-1) is 80.0 to 99.0% by mass in 100% by mass of the carbon material (B).
The invention according to any one of claims 1 to 3, wherein the content of graphite (B-1) is 90.0 to 97.5% by mass in 100% by mass of the carbon material (B). Conductive composition.
The conductive composition according to any one of claims 1 to 4, wherein the content of the carbon material (B) is 70 to 80% by mass based on 100% by mass of the solid content of the conductive composition. thing.
The conductive composition according to any one of claims 1 to 5, wherein the curing agent (C) contains an aziridine compound or an epoxy group-containing compound.
The conductive composition according to any one of claims 1 to 5, wherein the curing agent (C) contains a metal chelate.
The conductive composition according to claim 7, wherein the metal chelate contains an aluminum chelate.
A conductive film formed by forming the conductive composition according to any one of claims 1 to 8.
A non-contact medium loaded with a conductive circuit using the conductive composition according to any one of claims 1 to 8 and an IC chip.