JP2021009640A - Non-contact medium - Google Patents

Abstract

To provide a non-contact medium excellent in communication performance at a low cost by adjusting a mixing ratio of a binder resin and a carbon material and a mixing ratio of graphite to carbon other than graphite as the carbon material in a conductive composition used for forming a conductive circuit to a certain specific range to form the conductive circuit specifically excellent in adhesiveness to a base material and conductivity.SOLUTION: A non-contact medium mounting a conductive circuit and an IC chip is provided, in which: the conductive circuit is formed by using a conductive composition containing a binder resin (A) and a carbon material (B); the carbon material (B) contains graphite (B-1) and a carbon material (B-2) other than graphite; a mass ratio of a solid content of the binder resin (A) to the carbon material (B) is 15:85 to 35:65; and a content of the graphite (B-1) is 70 to 99 mass% based on 100 mass% of the carbon material (B).SELECTED DRAWING: None

Description

The present invention relates to a non-contact medium loaded with a conductive circuit and an IC chip.

The formation of thin films for electronic components such as non-contact media loaded with conductive circuits and IC chips or electromagnetic wave shielding, or the patterning of conductive circuits is generally performed with heat-curable or thermoplastic conductive inks. Alternatively, a method of printing a circuit pattern and sintering it by heat treatment, or an etching method from a copper-clad substrate is known.

As an example of the sintering method, Japanese Patent Application Laid-Open No. 2000-305260 describes as a photosensitive conductive paste, a photosensitive resin composition composed of an alkali-soluble negative type photosensitive resin composition, a photopolymerization initiator, a metal powder and metal ultrafine particles. The paste is disclosed. In the publication, after patterning the photosensitive resin composition, an organic component is volatilized in a firing furnace such as an electric furnace or a belt furnace, and an inorganic powder is fired to form a conductive pattern film. The firing atmosphere is in the air, nitrogen atmosphere, or hydrogen atmosphere, and the temperature is 500 ° C. or higher, which requires large-scale equipment. However, it is difficult to apply the sintering method to flexible packaging materials such as films and papers because the sintering temperature is high.

The etching method is to chemically or electrochemically dissolve and remove the surface and shape of a metal, and use it as a processing technique in a broad sense including surface treatment. Etching is a type of chemical processing, and is mainly performed to obtain a desired pattern shape on a metal surface, but there is a problem because the process is generally complicated and waste liquid treatment is required in a subsequent process. There are many. Further, since the conductive circuit formed by the etching method is formed only of a metal such as aluminum or copper, there is a problem that it is vulnerable to a physical impact such as bending.

The printing method using conductive ink can be expected to reduce the size and weight of electronic components, improve productivity, and reduce costs, and can easily impart conductivity by printing or coating on a base material and drying it. Since this printing method using conductive ink can be performed at a low temperature in the drying and curing steps without applying a high temperature to the base material and electronic parts, the demand for it has been rapidly increasing in recent years.

As a specific example, in order to realize a ubiquitous society, practical application of IC tags and RFID tags is being studied in various fields, and conductive as a means for manufacturing a large number of IC tags and RFID tags in a short period of time. The formation of antenna circuits by printing sex ink is being put to practical use. However, in order to function normally as an antenna, a circuit printed with ink with good conductivity is required, but a circuit with conductive ink using a metal filler such as silver or copper is common, and the material cost is high. In terms of aspects, its use is limited. For example, in Japanese Patent Application Laid-Open No. 2007-197558, an RFID tag is manufactured by using a conductive ink using silver powder. On the other hand, various studies have been conducted on conductive inks that use inexpensive conductive carbon instead of metal, but it is easy to imagine that the application to RFID tags will be severe due to insufficient conductivity. To.

Japanese Unexamined Patent Publication No. 2000-305260 JP-A-2007-197558

An object of the present invention is to set the mixing ratio of the binder resin and the carbon material in the conductive composition used for forming the conductive circuit and the mixing ratio of graphite as the carbon material and carbon other than graphite within a specific range, and to the base material. By forming a conductive circuit having specifically excellent adhesion and conductivity of graphite, it is possible to provide a non-contact type medium having excellent communication performance at low cost.

That is, the present invention is a non-contact medium loaded with a conductive circuit and an IC chip.
The conductive circuit is a conductive circuit formed by using a conductive composition containing a binder resin (A) and a carbon material (B).
The carbon material (B) contains graphite (B-1) and a carbon material other than graphite (B-2).
The mass ratio of the solid content of the binder resin (A) to the carbon material (B) is 15:85 to 35:65.
The present invention relates to a non-contact medium characterized in that the content of graphite (B-1) is 70 to 99% by mass in 100% by mass of the carbon material (B).

The present invention relates to the non-contact type media, wherein the content of graphite (B-1) is 80 to 99% by mass in 100% by mass of the carbon material (B).

The present invention relates to the non-contact type media, wherein the content of graphite (B-1) is 90 to 97.5% by mass in 100% by mass of the carbon material (B).

The present invention relates to the non-contact type medium, wherein the mass ratio of the solid content of the binder resin (A) to the carbon material (B) is 20:80 to 30:70.

The present invention relates to the non-contact type media, wherein the carbon material (B-2) other than graphite contains carbon black.

The mixing ratio of the binder resin and the carbon material in the conductive composition used for forming the conductive circuit and the mixing ratio of graphite as the carbon material and carbon other than graphite are set within a specific range, and the adhesion and conductivity to the base material are set. By forming a conductive circuit that is specifically excellent in graphite, it is possible to provide a non-contact type medium having excellent communication performance at low cost.

<Non-contact media>
The non-contact type media (non-contact type information recording medium) of the present invention is a non-contact type medium on which a conductive circuit and an IC chip are loaded, and the conductive circuit contains a binder resin (A) and a carbon material (B). It is characterized in that it is formed by using the contained conductive composition.

<Conductive composition>
The conductive composition used for the non-contact media of the present invention contains a binder resin (A), a carbon material (B), and a solvent, if necessary.

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

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

Binder resins are polyurethane-based, polyamide-based, acrylonitrile-based, acrylic-based, butadiene-based, polyvinyl butyral-based, polyolefin-based, polyester-based, polystyrene-based, EVA (ethylene-vinyl acetate copolymer) -based, epoxy-based, polyvinylidene fluoride. It can contain one or more selected from the group consisting of based and silicon-based resins. In particular, polyurethane-based, polyamide-based, and polyester-based are preferable. However, it is not limited to these resins. One type of binder resin may be used alone, or two or more types may be used in combination.
The binder resin can also be a curable resin that undergoes a curing (crosslinking) reaction after the binder resin is applied to the base material.
That is, the binder resin 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 cured (crosslinked). You can also.

As the binder resin, a polyurethane resin is preferable from the viewpoint of volume resistivity, adhesion to a base material, and durability. When the conductive composition is printed or coated on the substrate and then (heat) pressed, the resin content softens, and the flat pattern shape of the conductive circuit during printing and coating is almost maintained. On the other hand, when the fluid flows in the thickness direction, the voids can be reduced and the contact between the conductive carbon materials (B) can be increased, so that the volume resistivity of the obtained conductive circuit can be expected to decrease. Therefore, as the binder resin, one that moderately softens and flows during (heat) pressing is preferable.

<Polyurethane resin>
The method for synthesizing the polyurentane resin is not particularly limited, but for example, the polyol compound (a) and the diisocyanate (b) may be reacted, or the polyol compound (a), the diisocyanate (b) and the diol compound (c) having a carboxyl group may be reacted. To obtain a urethane prepolymer (d) having an isocyanate group, to further react the urethane prepolymer (d) with the polyamino compound (e), or to react as necessary in the above three cases. Examples thereof include those obtained by reacting a terminator.

As the polyol compound (a), various polyether polyols, polyester polyols, polycarbonate polyols, polybutadiene glycols, or a mixture thereof, which are generally known as polyol components constituting the polyurethane resin, can be used.

Examples of the polyether polyols include polymers or copolymers of ethylene oxide, propylene oxide, tetrahydrofuran and the like.
Examples of polyester polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3-methyl-1, Saturated and unsaturated low molecular weight diols such as 5-pentanediol, hexanediol, octanediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, dimerdiol, and n-butylglycidyl ether, 2 -Alkyl glycidyl ethers of ethylhexyl glycidyl ethers, monocarboxylic acid glycidyl esters such as versatic acid glycidyl esters, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, Dicarboxylic acids such as malonic acid, glutaric acid, pimelli acid, suberic acid, azelaic acid, and sebacic acid, or anhydrides thereof are dehydrated and condensed to obtain polyester polyols or cyclic ester compounds. Examples thereof include the obtained polyester polyols.
As the polycarbonate polyols, 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 can be mentioned. 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 is appropriately determined in consideration of the solubility of the polyurethane resin in producing the conductive composition, the durability of the conductive circuit formed, the adhesive strength to the substrate, and the like. However, it is usually preferably in the range of 580 to 8000, and more preferably 1000 to 5000.
The above polyol compound 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 can be replaced with low molecular weight diols, for example, various low molecular weight diols used for producing the polyol compound.

As the diisocyanate compound (b), aromatic diisocyanates, aliphatic diisocyanates, alicyclic isocyanates, or mixtures thereof can be used, but isophorone diisocyanates are particularly preferable. Examples of the aromatic diisocyanate include 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-benzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, and 1, , 3-phenylenediocyanate, 1,4-phenylenediocyanate, tolylene diisocyanate, xylylene diisocyanate and the like.

Examples of the aliphatic diisocyanate include butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate.
Examples of the alicyclic diisocyanate include cyclohexane-1,4-diisocyanate, isophorone diisocyanate, norbornane diisocyanate methyl, bis (4-isocyanatecyclohexyl) methane, 1,3-bis (isocyanatemethyl) cyclohexane, and methylcyclohexanediisocyanate. Be done.

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. In particular, dimethylolpropionic acid and dimethylolbutanoic acid are preferable from the viewpoint of reactivity and solubility.
The conditions 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 are other than making the isocyanate group excessive. Although not particularly limited, the isocyanate group / hydroxyl group equivalent ratio is preferably in the range of 1.05 / 1-3 / 1. More preferably, it is 1.2 / 1 to 2/1. The reaction is usually carried out at room temperature to 150 ° C., and is preferably carried out at 60 to 120 ° C. from the viewpoint of controlling the production time and side reactions.

The polyamino compound (e) acts as a chain extender, and includes ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, norbornandiamine, and 2 Amines having a hydroxyl group such as- (2-aminoethylamino) ethanol, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, and di-2-hydroxypropylethylenediamine can also be used. it can. Of these, isophorone diamine is preferably used.

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

The conditions for reacting the urethane prepolymer (d) having an isocyanate group with the polyamino compound (e) and, if necessary, a reaction terminator are not particularly limited, but the free isocyanates at both ends of the urethane prepolymer are not particularly limited. When the number of groups is 1 equivalent, the total equivalent of the polyamino compound (e) and the amino groups in the reaction terminator is preferably in the range of 0.5 to 1.3. More preferably, it is in the range of 0.8 to 0.995.
The weight average molecular weight of the polyurethane resin is preferably in the range of 5000 to 20000 from the viewpoint of coatability and handleability.

When synthesizing a polyurethane resin, one type selected from ester solvents, ketone solvents, glycol ether solvents, aliphatic solvents, aromatic solvents, alcohol solvents, carbonate solvents, water, etc. may be used alone or in combination of two. The above can be used in combination.
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, cyclohexanenon and the like.
Glycol ether-based solvents 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 ether, propylene glycol monoethyl ether, and acetate esters 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, ethyl methyl carbonate, di-n-butyl carbonate and the like.

<Polyamide resin>
As the binder resin, a polyamide resin is preferable from the viewpoint of volume resistivity and adhesion to the substrate. The volume resistivity is a good result because the resin component in the (heat) press easily flows.
The polyamide resin used in the present invention is basically 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, or ring-opening polymerization of lactam. This is a mixture of various modified polyamides, products manufactured with a partially hydrogenated reaction product, products with a partial copolymerization of other monomers, or other substances such as various additives. It is a broad concept that includes things.

The polyamide resin used in the present invention is not particularly limited as long as the above conditions are satisfied, but a dimer acid-modified polyamide resin obtained by condensation polymerization of a dibasic acid containing dimer acid as a main component and polyamines is preferable. .. As the dimer acid for producing a dimer acid-modified polyamide resin, dimer acid obtained by polymerizing a natural monobasic unsaturated fatty acid contained in tall oil fatty acid, soybean oil fatty acid, etc. is widely used industrially, but in principle. May be various dicarboxylic acids such as saturated fatty acids, unsaturated fatty acids, alicyclic, or aromatic acids.
Examples of commercially available products of the dimer acid include Hari Dimer 200, 300 (manufactured by Harima Chemicals, Inc.), Versa Dimer 228, 216, Empole 1018, 1019, 1061, 1062 (manufactured by Cognis Co., Ltd.) and the like. Further, hydrogenated dimer acid can also be used, and examples of commercially available hydrogenated dimer acids include Prepol 1009 (manufactured by Claude Japan Co., Ltd.) and Empole 1008 (manufactured by Cognis Co., Ltd.).
In addition to the 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, bimelic 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-hexadecandicarboxylic 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.
As a dibasic acid having a phenolic hydroxyl group,
Hydroxyisophthalic acids such as 2-hydroxyisophthalic acid, 4-hydroxyisophthalic acid, 5-hydroxyisophthalic acid,
Dihydroxyisophthalic acids such as 2,5-dihydroxyisophthalic acid, 2,4-dihydroxyisophthalic acid, 4,6-dihydroxyisophthalic acid,
Dihydroxyterephthalic acids such as 2-hydroxyterephthalic acid, 2,3-dihydroxyterephthalic acid, 2,6-dihydroxyterephthalic acid,
Hydroxyphthalic acids such as 4-hydroxyphthalic acid and 3-hydroxyphthalic acid,
Examples thereof include dihydroxyphthalic acids 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.
Of these, 5-hydroxyisophthalic acid is preferable from the viewpoint of copolymerizability and easy availability.

Further, various monocarboxylic acids are used as needed in order to obtain a polyamide resin having appropriate fluidity when heated. Specifically, as the monocarboxylic acid, propionic acid, acetic acid, caprylic acid (octanoic acid), stearic acid, oleic acid and the like are used.
The polyamines as a reaction product in producing the dimer acid-modified polyamide resin are, for example, various diamines such as aliphatic, alicyclic and aromatic diamines, triamines and polyamines. Specific examples of the above diamines include ethylenediamine, propanediamine, butanediamine, triethylenediamine, tetraethylenediamine, hexamethylenediamine, p- or m-xylenediamine, 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 Aminopiperazine, piperazine and the like can be mentioned.
Further, examples of the triamine include diethylenetriamine, and examples of the polyamine include triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine. Further, a dimer diamine obtained by converting a dimerized aliphatic nitrile group and reducing it with hydrogen can also be used.

Examples of the polyamine compound include 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, and examples of commercially available products include clover. Examples thereof include "Priamine 1071", "Priamine 1073", "Priamine 1074" and "Priamine 1075" manufactured by Japan Co., Ltd. and "Versamine 551" manufactured by Cognis Japan Co., Ltd.
Alkanolamine may be used in combination with the diamine. Examples of alkanolamines include ethanolamine, propanolamine, diethanolamine, butanolamine, 2-amino-2-methyl-1-propanol, 2- (2-aminoethoxy) ethanol and the like. Further, a polyether diamine having oxygen in its skeleton can be used. This polyether has the general formula H ₂ N − R ₁ − (RO) _{n −} R ₂ −NH ₂ (in the formula, n is 2 to 100, and R ₁ and R ₂ have 1 to 14 carbon atoms. An alkylene group or a divalent alicyclic hydrocarbon group, where R is an alkylene group or a divalent alicyclic hydrocarbon group having 1 to 10 carbon atoms. The alkylene group is linear. It may be in the form of a branched chain or a branched chain.) Examples of this ether diamine include polyoxypropylene diamine, and commercially available products include Jeffamines (manufactured by San Techno Chemical Co., Ltd.). Further, bis- (3-aminopropyl) -polytetrahydrofuran can also be mentioned.
The 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. Generally, the reaction temperature is about 100 to 300 ° C., and the reaction time is about 1 to 8 hours.

<Polyester resin>
As the binder resin, a polyester resin is preferable from the viewpoint of volume resistivity and adhesion to the base material. The volume resistivity is a good result because the resin component in the (heat) press easily flows.
The polyester resin is a polymer composed of a polyvalent carboxylic acid and a polyhydric alcohol as a monomer. As the polyester resin, known ones can be adopted, and specifically, from the viewpoint of ensuring the cohesive force of the resin, the weight average molecular weight is preferably 1000 to 100,000. Further, from the viewpoint of adhesion, the glass transition temperature 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, trivalent or higher carboxylic acids, and one or two of these. The above can be selected and used. On the other hand, examples of the polyhydric alcohol component constituting the polyester resin include aliphatic glycols, ether glycols, and trihydric or higher polyalcohols, and one or more of these can be selected and used.
Commercially available polyester resins include Byron (manufactured by Toyo Spinning Co., Ltd., "Byron" is a registered trademark), Polyester (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., "Polyester" is a registered trademark), and Tesslac (manufactured by Hitachi Chemical Polymer Co., Ltd.). , "Tesslac" is a registered trademark).

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

The conductive carbon material (B) in the conductive composition of the present invention is characterized by containing graphite (B-1) and a carbon material (B-2) other than graphite.
The mass ratio of the binder resin (A) to the carbon material (B) is preferably 15:85 to 35:65, preferably 20:80 to 30:70.

If the mass ratio of the binder resin is less than 15, the adhesion of the conductive circuit is lowered, resulting in poor adhesion. On the other hand, when the mass ratio of the binder resin exceeds 35, the contact between the carbon materials in the conductive circuit is hindered, and the conductivity becomes poor.

When the mass ratio of the binder resin is 20 to 30, adhesion can be exhibited without hindering the formation of the conductive network in the conductive circuit formed by the conductive composition.

As the graphite (B-1), for example, artificial graphite, natural graphite, or the like can be used. Artificial graphite is made by artificially orienting irregularly arranged micrographite crystals by heat treatment of amorphous carbon, and is generally manufactured using petroleum coke or coal-based pitch coke as the main raw material. To. 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 expansive graphite) obtained by chemically treating scaly graphite, or expanded graphite obtained by heat-treating expanded graphite to expand it and then refining it or pressing it. You can. Among these graphites, when used in a conductive circuit 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 subjected to surface treatments such as epoxy treatment, urethane treatment, silane coupling treatment, oxidation treatment and the like in order to increase the affinity with the binder resin as long as the characteristics of the conductive composition of the present invention are not impaired. May be applied.

The average particle size of the graphite used is preferably 2 to 100 μm, particularly preferably 20 to 50 μm.

If the average particle size of graphite is less than 2 μm, the aspect ratio of the graphite particles is lowered, and the contact between the graphite particles tends to be point contact, so that a conductive network cannot be sufficiently formed. On the other hand, when the average particle size of graphite is 100 μm or more, the voids between the graphite particles become large, and the proportion of conductive paths formed between carbon materials other than graphite in the conductive network increases, causing a decrease in conductivity.

The average particle size referred to in the present invention is 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. It is measured with a standard particle size distribution meter, for example, a dynamic light scattering type particle size distribution meter (“Microtrack UPA” manufactured by Nikkiso Co., Ltd.).

As commercially available graphite, for example, as flaky graphite, CMX, CPB, UP-5, UP-10, UP-20, UP-35N, CSSP, CSPE, CSP, CP, CB-150 manufactured by Nippon Graphite Industry Co., Ltd. , 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, CX-3000, FBF, BF, CBR, SSC-3000, SSC-600, SSC-3, SSC, CX-600, CPF-8, CPF-3, manufactured by Chuetsu Graphite Co., Ltd. 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, EC1500, EC1000, EC500, EC300, EC100, EC50, Nishimura Graphite Co., Ltd. 10099M, PB-99 and the like. Examples of spherical natural graphite include CGC-20, CGC-50, CGB-20, and CGB-50 manufactured by Nippon Graphite Industry Co., Ltd. Examples of earth-like graphite include blue P, AP, AOP, P # 1 manufactured by Nippon Graphite Industry Co., Ltd., and APR, S-3, AP-6, 300F manufactured by Chuetsu Graphite Co., Ltd. As artificial graphite, PAG-60, PAG-80, PAG-120, PAG-5, HAG-10W, HAG-150 manufactured by Nippon Graphite Industry Co., Ltd., RA-3000, RA-15, RA- of Chuetsu Graphite Co., Ltd. 44, GX-600, G-6S, G-3, G-150, G-100, G-48, G-30, G-50, SGP-100, SGP-50, SGP-25 manufactured by SEC Carbon Co., Ltd. , SGP-15, SGP-5, SGP-1, SGO-100, SGO-50, SGO-25, SGO-15, SGO-5, SGO-1, SGX-100, SGX-50, SGX-25, SGX -15, SGX-5, SGX-1 can be mentioned. The present invention is not limited to these, and two or more types may be used in combination.

The content of graphite (B-1) in the conductive composition in the present invention is 70 to 99% by mass in 100% by mass of the carbon material (B), and in particular, 100% by mass of the carbon material (B). In%, it is preferably 75 to 99% by mass, more preferably 80 to 99% by mass in 100% by mass of the carbon material (B), and further 90 to 97% in 100% by mass of the carbon material (B). It is preferably 5% by mass.

When the content of graphite (B-1) is less than 70% by mass in 100% by mass of the carbon material (B), the orientation of the graphite particles is lowered due to the excess amount of the carbon material (B-2) other than graphite. Since most of the conductive network is occupied by carbon materials other than graphite, high conductivity is not exhibited. Further, if it is 75% by mass or more in 100% by mass of the carbon material (B), specific high conductivity is exhibited. On the other hand, when the graphite content exceeds 99% by mass in 100% by mass of the carbon material (B), the conductivity in the plane direction by the graphite particles becomes dominant, and the conductivity of the conductive circuit reaches a plateau.

When the content of graphite (B-1) is 80% by mass or more in 100% by mass of the carbon material (B), pinholes in the conductive circuit are few and a good coating film can be formed.

When the content of graphite (B-1) is 90 to 97.5% by mass in 100% by mass of the carbon material (B), in addition to the high conductivity in the plane direction due to the graphite particles, an appropriate amount of graphite other than graphite is added. The carbon material (B-2) of No. 1 can strengthen the conductive network in the vertical direction without inhibiting the conductivity in the plane direction derived from graphite, and can exhibit very high conductivity.

When the content of graphite (B-1) is less than 90% by mass in 100% by mass of the carbon material (B), a coating film having less unevenness in the conductive circuit can be obtained.

(Carbon material other than graphite (B-2))
The carbon material other than graphite is not particularly limited, but carbon black is more preferable from the viewpoint of particle size and specific surface area. In addition, conductive carbon fibers (carbon nanotubes, carbon nanofibers, carbon fibers), fullerenes and the like can be used alone or in combination of two or more.

Carbon black includes 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 burn the flame to the bottom of the channel steel. Various types such as channel black that has been rapidly cooled and precipitated, thermal black that is obtained by periodically repeating combustion and thermal decomposition using gas as a raw material, and acetylene black that uses acetylene gas as a raw material, alone or 2 More than one type can be used together. In addition, normally oxidized carbon black, hollow carbon, and the like can also be used.

Oxidation treatment of carbon is performed by treating carbon at a high temperature in air or secondary treatment with nitrate, nitrogen dioxide, ozone, etc., for example, phenol group, quinone group, carboxyl group, carbonyl group, etc. It is a process of directly introducing (covalently bonding) an oxygen-containing polar functional group to the carbon surface, and is generally performed to improve the dispersibility of carbon. However, since the conductivity of carbon generally decreases as the amount of functional groups introduced increases, it is preferable to use carbon that has not been oxidized.

As the specific surface area of the carbon black used increases, the contact points between the carbon black particles increase, which is advantageous in lowering the volume resistivity. Specifically, the specific surface area (BET) obtained from the amount of nitrogen adsorbed is 20 m ² / g or more and 1500 m ² / g or less, preferably 50 m ² / g or more and 1500 m ² / g or less, and more preferably 100 m ² / G or more,
It is desirable to use the one of 1500 m ² / g or less. If carbon black having a specific surface area of less than 20 m ² / g is used, it may be difficult to obtain sufficient conductivity, and carbon black having a specific surface area of more than 1500 m ² / g may be difficult to obtain as a commercially available material. is there.

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

Examples of commercially available carbon black include Tokai Carbon's Toka Black # 4300, # 4400, # 4500, # 5500, Degussa's Printex L, and Colombian's Raven 7000, 5750, 5250, 5000 ULTRAIII, 500.
0ULTRA, ConductexSCULTRA, Conductex975ULTRA, PUERBLACK100, 115,205, Mitsubishi Chemical # 2350, # 2400B, # 2600B, # 3050B, # 3030B, # 3230B, # 3350B, # 3400B, # 5400B, Cabot 1300, 900, Vulcan XC-72R, BlackPearls2000, Ensaco250G, Ensaco260G, Ensaco350G, SuperP-Li, etc. Furness Black manufactured by TIMCAL), EC-300J, EC-600JD, etc. Examples thereof include acetylene black manufactured by Denka Black, Denka Black HS-100, FX-35, etc., but the present invention is not limited to these, and two or more types may be used in combination.

As the conductive carbon fiber, those obtained by firing from a raw material derived from petroleum are preferable, but those 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 nanotube shows a large value of 30 nm with respect to 0.7-2.0 nm of a typical single-walled carbon nanotube.

Examples of commercially available conductive carbon fibers and carbon nanotubes include vapor-phase carbon fibers such as VGCF manufactured by Showa Denko, EC1.0, EC1.5, EC2.0, and EC1.5-P manufactured by Meijo Nanocarbon. Examples thereof include single-walled carbon nanotubes manufactured by CNano, FloTube9100, FloTube9100, FloTube9110, FloTube9200, NC7000 manufactured by Nanocyl, and 100T manufactured by Knano.

Next, the solvent will be described. When the binder resin (A) in the conductive composition and the conductive carbon material (B) are uniformly mixed, a solvent can be appropriately used. Examples of such a solvent include organic solvents and water.
Organic solvents 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, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether and the like. Suitable for the composition of the conductive composition from among ethers, hydrocarbons such as hexane, heptane and octane, aromatics such as benzene, toluene, xylene and cumene, and esters such as ethyl acetate and butyl acetate. Can be used. Further, two or more kinds of solvents may be used.
When a printing coating method in which a conductive composition such as screen printing is required to have a viscosity of a certain level or higher is adopted, the viscosity of the organic solvent at 25 ° C. is preferably 30 mPa · s to 75,000 mPa · s. If it is less than 30 mPa · s, high conductivity is exhibited and the resin content is small. Therefore, good dispersibility of the viscous and conductive carbon material suitable for coating cannot be obtained, and the coating property is insufficient. If it exceeds 75,000 mPa · s, the viscosity of the carbon material is significantly lowered because the viscosity is too high. For example, tarpineol, dihydroterpineol, 2,4-diethyl-1,5-pentanediol, 1,3-butylene glycol, isobornylcyclohexanol can be mentioned. Two or more kinds of high-viscosity solvents shown here may be used, and the viscosity at 25 ° C. such as methyl ethyl ketone, toluene, and isopropyl alcohol is 30 mPa · s.
It can also be used in combination with a low viscosity solvent of less than.

Next, other components will be described. The conductive composition of the present invention contains, if necessary, an ultraviolet absorber, an ultraviolet stabilizer, a radical catching agent, a filler, a thixotropic agent, an antistatic agent, and an antioxidant, as long as the effects of the present invention are not impaired. Agents, antistatic agents, flame retardants, thermal conductivity improvers, plasticizers, anti-sag agents, antifouling agents, preservatives, bactericides, defoamers, leveling agents, anti-blocking agents, hardeners, thickeners, Various additives such as a pigment dispersant and a silane coupling agent may be added.

(Disperser / Mixer)
As an apparatus used for obtaining the conductive composition, a disperser or a mixer usually used for pigment dispersion or the like can be used.

For example, mixers such as disper, homomixer, or planetary mixer; homogenizers such as "Clearmix" manufactured by M-Technique or "Philmix" manufactured by PRIMIX; paint conditioner (manufactured by Red Devil), ball mill, sand mill. (Symmal Enterprises "Dyno Mill", etc.), Atwriter, Pearl Mill (Eirich "DCP Mill", etc.), or media type disperser such as Coball Mill; Wet Jet Mill (Genus "Genus PY", Sugino) Medialess dispersers such as Machine's "Starburst", Nanomizer's "Nanomizer", etc.), M-Technique's "Claire SS-5", or Nara Machinery's "MICROS"; However, it is not limited to these.

For example, when using a media-type disperser, a method in which the agitator and vessel use a disperser 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. Is preferably used. As the medium, it is preferable to use glass beads, zirconia beads, or ceramic beads such as alumina beads. As the disperser, only one type may be used, or a plurality of types of devices may be used in combination.

(Conductive circuit)
In the conductive circuit used for the non-contact media of the present invention, the above conductive composition is printed on one or both sides of a base material such as paper or plastic depending on the intended use, such as screen printing, rotary screen printing, and flexo printing. , Gravure printing, gravure offset printing, offset printing, letterpress printing, inkjet, and other ordinary printing methods can be used to form a conductive circuit.

As the paper base material, various processed papers such as coated paper, non-coated paper, synthetic paper, polyethylene-coated paper, impregnated paper, water-resistant processed paper, insulating processed paper, and stretch-processed paper can be used, but as non-contact media. In order to obtain a stable resistance value, coated paper and processed paper are preferable. 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 the conductive ink of the present invention, a conductive circuit can be formed by a normal printing method, so that a design utilizing existing equipment is possible. That is, since it is possible to print and form a conductive circuit as it is after performing normal printing to enhance the design of non-contact media such as a pattern, circuit formation that has been conventionally performed by an etching method or a transfer method. It is far superior in terms of productivity, initial investment cost, and running cost compared to the law.
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.

It is also possible to obtain a non-contact medium by applying an adhesive on the 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 conductor circuit manufactured by the above method is loaded on the base material together with the IC module, and a non-contact ID is obtained. The base material holds the conductor circuit and the IC chip, and paper, film, or the like similar to the base material of the conductor circuit can be used. In addition, the IC chip stores, stores, and calculates data. The non-contact ID is an RFID (Radio Frequency Identification), a non-contact IC card, a non-contact IC tag, a data carrier (recording medium), a wireless card, and an individual using radio waves with a reader or a reader / writer. It identifies and sends and receives data. Its uses include ID management and history management of toll collection systems, and location management of road usage status management systems, cargo, and luggage tracking / management systems.

(Volume resistivity of conductive circuit)
The conductive circuit of the present invention preferably has a volume resistivity of less than 5 × 10 ^-2 Ω · cm. Since the volume resistivity is less than 5 × 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 with reference to Examples, but the following Examples do not limit the scope of rights of the present invention. In the examples and comparative examples, "parts" represents "parts by mass", Mw means weight average molecular weight, and Tg means glass transition temperature.

<Synthesis of binder resin A-1>
A polyester polyol (manufactured by Kuraray Co., Ltd.) obtained from terephthalic acid, adipic acid, and 3-methyl-1,5-pentanediol in a reaction vessel equipped with a stirrer, a thermometer, a reflux cooler, a dropping device, and a nitrogen introduction tube. "Kurare Polyester P-2011", Mn = 2011) 455.5 parts, 16.5 parts of dimethylolbutanoic acid, 105.2 parts of isophorone diisocyanate, 140 parts of toluene were charged and reacted at 90 ° C. for 3 hours in a nitrogen atmosphere. Toluene (360 parts) was added to obtain a urethane prepolymer solution having an isocyanate group. Next, a urethane prepolymer solution having an isocyanate group obtained by mixing 19.9 parts of isophoronediamine, 0.63 parts of di-n-butylamine, 294.5 parts of 2-propanol, and 335.5 parts of toluene. 969.5 parts were added and reacted at 50 ° C. for 3 hours followed by 70 ° C. for 2 hours, diluted with 126 parts of toluene and 54 parts of 2-propanol, Mw = 61,000, acid value = 10 mgKOH / g, urethane pre. A solution of polyurethane resin A-1 was obtained in which the total equivalent of the polyamino compound and the amino groups in the reaction terminator was 0.98 with respect to the free isocyanate groups at both ends of the polymer.

<Synthesis of binder resin A-2>
In a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen introduction tube, an introduction tube, and a thermometer, 156.2 g of prepol 1009 as a polybasic acid compound, 5.5 g of 5-hydroxyisophthalic acid, and preamine as a polyamine compound. 146.4 g of 1074 and 100 g of ion-exchanged water were charged, and the mixture was stirred until the temperature of heat generation became constant. When the temperature became stable, the temperature was raised to 110 ° C., and after confirming the outflow of water, the temperature was raised to 120 ° C. 30 minutes later, and then the dehydration reaction was continued while raising the temperature by 10 ° C. every 30 minutes. .. When the temperature reached 230 ° C., the reaction was continued at the same temperature for 3 hours, and the temperature was lowered by holding for 1 hour under a vacuum of about 2 kPa. Finally, an antioxidant was added to obtain a polyamide resin A-2 having 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.

The resin was evaluated as follows.
<Measurement method of weight average molecular weight (Mw)>
For the measurement of Mw, GPC (gel permeation chromatography) "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. In the measurement in the present invention, two "LF-604" (manufactured by Showa Denko KK: GPC column for rapid analysis: 6 mm ID x 150 mm size) are connected in series to the column, the flow rate is 0.6 ml / min, and the column temperature is set. It was carried out under the condition of 40 ° C., and the weight average molecular weight (Mw) was determined in terms of polystyrene.
<Measurement of acid value>
Precisely weigh about 1 g of the sample in an Erlenmeyer flask with a stopper, and add 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixture to dissolve the sample. Phenolphthalein test solution is added to this as an indicator and held for 30 seconds. Then, titrate with 0.1N alcoholic potassium hydroxide solution until the solution turns pink. The acid value was calculated by the following formula (unit: mgKOH / g). 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: Titer of 0.1N alcoholic potassium hydroxide solution <Measurement method of hydroxyl value>
The hydroxyl value is the amount of potassium hydroxide (mg) required to neutralize acetic acid bonded to the hydroxyl group when the hydroxyl group is acetylated, by expressing the amount of hydroxyl group contained in 1 g of the hydroxyl group-containing resin. Is. The hydroxyl value was measured according to JIS K0070. In the present invention, when calculating the hydroxyl value, the acid value is taken into consideration as shown in the following formula.
<Measurement of hydroxyl value>
Precisely weigh about 1 g of the sample in an Erlenmeyer flask with a stopper, and add 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixture to dissolve the sample. 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 TS is added as an indicator to this and lasts for 30 seconds. Then, titrate with 0.1N alcoholic potassium hydroxide solution until the solution turns pink.
The hydroxyl value was calculated by the following formula (unit: mgKOH / g).
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)
<Measurement method of glass transition temperature>
The solvent was dried and removed from the binder resin, and the temperature was measured at 2 ° C./min from −80 to 150 ° C. using “DSC-1” manufactured by METTLER TOLEDO Co., Ltd.

<Adjustment of binder resin>
The binder resin used in Examples and Comparative Examples 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: A solution of binder resin A-1-1 diluted with toluene / methyl ethyl ketone / 2-propanol (1/1/1 (mass ratio)). Got
-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: Binder resin A-3 obtained by diluting Byron 200 (manufactured by Toyo Boseki Co., Ltd., polyester resin) with toluene / methyl ethyl ketone (1/1 (mass ratio)). A solution of -1 was obtained.

<Conductive composition and conductive circuit>
(Example 1)
120 parts of A-1-1 solution as a binder resin (24 parts of resin solid content), 70 parts of B-1-1: scaly graphite CB-150 (manufactured by Nippon Graphite Co., Ltd.) as a conductive carbon material, other than graphite B2-11: Furness Black # 3050 (manufactured by Mitsubishi Chemical Co., Ltd.) as a carbon material, and 204 parts of toluene / methyl ethyl ketone / 2-propanol (1/1/1) as a solvent are mixed in a mixer. Then, it was further placed in a sand mill and dispersed to obtain a conductive composition (1).
With the obtained conductive composition, a circuit was prepared by the following method, and the conductive circuit and the non-contact type media were evaluated. The results are shown in Table 1.

(Volume resistivity 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, and a conductive circuit (10 cm × 10 cm coating film) for evaluating volume resistivity was obtained.
The volume resistivity of the conductive circuit was determined by measuring (JIS-K7194) by the 4-terminal method using Loresta GP (manufactured by Mitsubishi Chemical Analytech). The evaluation results are shown in Table 1.
⊚: “Volume resistivity is less than 5 × 10 ^-3 Ω · cm (extremely good)”
◯: “Volume resistivity of 5 × 10 ^-3 Ω ・ cm or more and less than 1 × 10 ^-2 Ω ・ cm (good)”
○ △: “Volume resistivity is 1 × 10 ^-2 Ω ・ cm or more and 5 × 10 ^-2 Ω ・ cm or less (usable)”
Δ: “Volume resistivity of 5 × 10 ⁻² Ω · cm or more and 1 × 10 ^-1 Ω · cm or less (defective)”
×: “Volume resistivity is 1 × 10 ^-1 Ω · cm or more (extremely defective)”

(Adhesion of conductive circuit)
The conductive composition (1) was applied onto a PEN 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, and a conductive circuit (10 cm × 10 cm coating film) for evaluation of adhesion was obtained.
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 2 mm intervals. An adhesive tape was attached to this notch and immediately peeled off, and the degree of detachment of the conductive circuit was visually determined. The evaluation results are shown in Table 1, and the evaluation criteria are shown below.
◯: "No peeling (level without practical problem)"
○ △: "Slight peeling (problem but usable level)"
Δ: "Half peeling"
×: "Peeling in most parts"

<Evaluation of coatability of conductive circuit>
The conductive composition (1) was applied onto a PEN 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, and a conductive circuit (10 cm × 10 cm coating film) for evaluation of coatability was obtained.

It was evaluated by the coatability evaluation shown below. The conductive circuit was visually observed, and uneven coating (unevenness: evaluated by the shade of the coated surface) and pinholes (evaluated by the presence or absence of defects to which the conductive circuit was not applied) were judged according to the following criteria. The evaluation results are shown in Table 1.
(village)
◯: The shading of the conductive circuit is not confirmed (good).
Δ: There are 1 to 3 shades of the conductive circuit, but it is an extremely minute region (no problem in practical use).
X: The shading of the conductive circuit is confirmed at four or more places, or the length of the shading stripes is 5 mm or more, and one or more (defective).
(Pinhole)
◯: No pinhole is confirmed (good).
Δ: There are 1 to 3 pinholes, but they are extremely small (no problem in practical use).
X: Four or more pinholes are confirmed, or one or more pinholes with a diameter of 1 mm or more (extremely defective).

(Non-contact media characteristics of conductive circuit)
A flexo plate (DSF version: made by DuPont) with a conductor pattern is attached to the second unit of the CI type 6-color flexo printing machine SOLOFLEX (manufactured by Windmoeller & Hoelscher KG), and 70 m / min on a PEN film (125 μm). The conductive composition (1) was sequentially printed at a speed. The film thickness of the printed matter is measured with a digital micro film thickness meter (MH15M manufactured by Nikon Corporation), the printing conditions are appropriately adjusted so that the average film thickness is 5 to 10 μm, and after heating and drying, it is used for evaluation of non-contact media characteristics. The conductive circuit of was obtained. An IC chip manufactured by Impinge Co., Ltd. was mounted on the obtained conductive circuit to create a non-contact media.
Next, we confirmed the availability of communication using Impingi's "fixed UHF band RFID reader / writer Speedway Revolution R420".
〇: Readable ×: Unreadable

(Examples 2 to 41, Comparative Examples 1 to 12)
Conductive compositions (2) to (41) and (a) to (l) were obtained in the same manner as in the conductive composition (1) with the composition ratios shown in Table 1.
In Examples 16 and 27, since the type of binder resin was different from that in Example 1, the diluting solvent at the time of preparing the conductive composition was toluene / 2-propanol (2/1).
In Examples 17 and 28, since the type of binder resin was different from that in Example 1, the diluting solvent used when preparing the conductive composition was toluene / methyl ethyl ketone (1/1).

The materials used in the examples are shown below.
<Binder resin (A)>
-A-1: Polyurethane resin-A-2: Polyamide resin-A-3: Polyester resin Byron 200 (manufactured by Toyobo Co., Ltd.)
<Carbon material (B)>
<Graphite (B-1)>
B-1-1: Scale graphite CB-150 (manufactured by Nippon Graphite Co., Ltd.) Average particle size 40 μm (catalog)
B-1-2: Scale graphite CPB (manufactured by Nippon Graphite Co., Ltd.) Average particle size 20 μm (catalog)
B-1-3: Scale graphite FB-100 (manufactured by Nippon Graphite Co., Ltd.) Average particle size 80 μm (catalog)
B-1--4: Thinned graphite CMX (manufactured by Nippon Graphite Co., Ltd.) Average particle size 40 μm (catalog)
B-1-5: Spheroidal graphite CGB-50 (manufactured by Nippon Graphite Co., Ltd.) Average particle size 50 μm (catalog)
B-1-6: Expanded graphite LEP (manufactured by Nippon Graphite Co., Ltd.) Average particle size 100 μm (catalog)
B-1-7: Artificial graphite PAG-5 (manufactured by Nippon Graphite Co., Ltd.) Average particle size 50 μm (catalog)
<Carbon material other than graphite (B-2)>
・ B-2-1: Furness Black # 3050B (manufactured by Mitsubishi Chemical Corporation)
-B-2-2: Denka Black HS-100 (manufactured by Denki Kagaku Kogyo Co., Ltd.)
・ B-2-3: Ketjen Black EC-300J (manufactured by Lion Specialty Chemicals)
・ B-2-4: Carbon nanotube VGCF (manufactured by Showa Denko KK)
・ B-2-5: Ketjen Black EC-600JD (manufactured by Lion Specialty Chemicals)

Since the resistance value of the conductive circuit in Examples 1 to 41 was low, communication could be confirmed. On the other hand, in Comparative Examples 3, 4, 5, 6, 8, 9, 11, and 12, communication could not be confirmed because the resistance values were high. Further, in Comparative Examples 1, 2, 7, and 10, since the amount of the conductive particles filled 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 poor. , Practicality as a non-contact type medium is poor.

Claims (5)

A non-contact medium loaded with a conductive circuit and an IC chip.
The conductive circuit is a conductive circuit formed by using a conductive composition containing a binder resin (A) and a carbon material (B).
The carbon material (B) contains graphite (B-1) and a carbon material other than graphite (B-2).
The mass ratio of the solid content of the binder resin (A) to the carbon material (B) is 15:85 to 35:65.
A non-contact medium characterized in that the content of graphite (B-1) is 70 to 99% by mass in 100% by mass of the carbon material (B). The non-contact media according to claim 1, wherein the content of graphite (B-1) is 80 to 99% by mass in 100% by mass of the carbon material (B). The non-contact media according to claim 1 or 2, wherein the content of graphite (B-1) is 90 to 97.5% by mass in 100% by mass of the carbon material (B). The non-contact type according to any one of claims 1 to 3, wherein the mass ratio of the solid content of the binder resin (A) to the carbon material (B) is 20:80 to 30:70. media. The non-contact media according to any one of claims 1 to 4, wherein the carbon material (B-2) other than graphite contains carbon black.