TW201348400A - Electroconductive composition - Google Patents

Abstract

In the past, it has been difficult to stabilize electroconductivity in an electroconductive powder having elevated resistance in an acceleration test despite initially exhibiting conductivity, such as with an electroconductive composition in which a silver plating powder, nickel powder, or the like is used. The present invention enables stable elctroconductivity after a high-temperature and high-humidity test or heat shock test, as an acceleration test, irrespective of the type of electroconductive powder used. In particular, electroconductivity is stabilized even in an inexpensive electroconductive powder for which conductivity tends to become unstable. An electroconductive composition comprising components (A) to (E), and comprising 40 percent by mass or more of component (E) in relation to 100 percent by mass of the electroconductive composition. Component (A) is a curable epoxy resin, component (B) is an elastomer, component (C) is a rubber particulate, component (D) is a coupling agent, and component (E) is an electroconductive powder.

Description

Conductive composition

The present invention relates to an electrically conductive composition which is stable even under high temperature and high humidity conditions or in an environment where temperature changes greatly.

In recent years, as a substitute for solder, attention has been paid to a conductive composition, and a general conductive powder system uses silver powder. However, since the increase in the amount of silver metal is associated with a high cost, the conductive composition is also replaced with an inexpensive conductive powder. In Patent Document 1, an attempt is made to reduce the cost by using a so-called plating powder which is only an inexpensive powder of a precious metal which is surface-plated and expensive.

Further, Patent Document 2 describes an invention in which a conductive composition containing an organic filler is added. This is added by dispersing the internal stress to prevent cracking of the hardened material or to reduce the stress on the adherend.

[Previous Technical Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 6-157876

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2003-313427

However, the plating powder used in Patent Document 1 exhibits an initial stage. In the conduction test, in the accelerated test such as the high temperature and high humidity test and the heat cycle test, the tendency of the resistance value to rise with time was observed. Further, in the conductive composition of Patent Document 2, only the influence on the initial conductivity is described.

Therefore, in the past, in the case of using a conductive composition such as silver plating powder or nickel powder, although the initial conductivity is exhibited, in the conduction test, it is difficult to stabilize the conductivity in the conductive powder having an increased resistance value. .

The present inventors have found a method for a conductive composition in order to achieve the above object and have completed the present invention.

Next, the gist of the present invention will be described. The first embodiment includes the following components (A) to (E), and the component (E) is contained in an amount of 40% by mass or more (including 40% by mass) based on 100% by mass of the conductive composition.

(A) component: hardenable epoxy resin

(B) Component: Elastomer

(C) Component: Rubber particles

(D) Ingredients: coupling agent

(E) component: Conductive powder.

A second embodiment of the present invention is the conductive composition according to the first embodiment, wherein the component (A) comprises an epoxy resin having one epoxy group in the molecule.

A third embodiment of the present invention is the conductive composition of the second embodiment, which further comprises an epoxy group-forming latent curing agent.

The fourth embodiment of the present invention is the conductive composition of any one of the first to third embodiments, wherein the component (E) comprises a dendritic shape The surface of the copper powder is subjected to silver plating powder.

The fifth embodiment of the present invention is the conductive composition according to any one of the first to fourth aspects, wherein the component (C) is a core-shell type acrylic particle.

The sixth embodiment of the present invention is the conductive composition according to any one of the first to fifth aspects, wherein the component (D) is a decane-based coupling agent having an epoxy group.

The seventh embodiment of the present invention contains the conductive composition of any of the first to sixth embodiments.

1‧‧‧Electrical composition

2‧‧‧Aluminum sheet

3‧‧‧Insulation tape

Fig. 1 is a schematic view showing the test speed for the accelerated test by the high temperature and high humidity or the accelerated test by the thermal cycle.

[To implement the type of invention]

The first embodiment of the present invention contains the conductive composition of the following components (A) to (E), and the component (E) is contained in an amount of 40% by mass or more (including 40% by mass) based on 100% by mass of the conductive composition. (A) component: curable epoxy resin, (B) component: an elastomer, (C) component: rubber particle, (D) component: coupling agent, (E) component: electroconductive powder. By adopting such a configuration, regardless of the type of the conductive powder, it is possible to have stable conductivity after the high-temperature high-humidity test or the heat shock test for promoting the test. Especially in the conduction is easy to be unstable In the inexpensive conductive powder, the conductivity is also stabilized. Further, in the field of electronic components, metals of various materials such as aluminum alloys and stainless steels are used, and metals which are violently oxidized among metals are used, and conduction defects may occur in the conductive composition. However, the present invention exhibits stable conductivity even in such a metal, and can be expanded in various types of electronic parts that require stability and ensure continuity.

Next, the contents of the present invention will be described. The component (A) which can be used in the present invention is a curable epoxy resin. Among them, the curable epoxy resin refers to a mixture of an epoxy resin and a hardener. That is, the component (A) corresponds to an epoxy resin which is hardened by heating.

The epoxy resin is not particularly limited as long as it has at least one epoxy group in one molecule. Although various epoxy resins can be used, a polyvalent epoxy resin having two or more (including two) epoxy groups in one molecule is mainly used. Further, in order to reduce the viscosity, it is preferred to use an epoxy resin having a monovalent epoxy group in one molecule, and to use a polyvalent epoxy resin and a monovalent one having an epoxy group in one molecule. The mixture of epoxy resins is better.

Specific examples of the polyvalent epoxy resin are obtained by condensing polyphenols or polyhydric alcohols such as epichlorohydrin and bisphenols, and examples thereof include bisphenol A type, brominated bisphenol A type, and hydrogenated bisphenol. Type A, bisphenol F type, bisphenol S type, bisphenol AF type, biphenyl type, naphthalene type, anthraquinone type, phenolic type, phenol novolac type, o-cresol novolac type, tris(hydroxyphenyl)methane type, Epoxy propylene ether type epoxy resin such as tetraphenol ethane type; ethylene glycol, propylene glycol, butane diol, hexane diol, polyethylene glycol, thiodiglycol, glycerol, trimethylolpropane A polyglycidyl ether of a polyhydric alcohol such as pentaerythritol, sorbitol, or a bisphenol A-ethylene oxide adduct. Other, can be listed For example, a glycidyl ester type epoxy resin obtained by condensing an epichlorohydrin with a decanoic acid derivative or a fatty acid such as a fatty acid; an epichlorohydrin with an amine, a cyanuric acid or a carbendazim The epoxy propylamine type epoxy resin obtained by the reaction; the epoxy resin further modified by various methods, but is not limited thereto.

The monovalent epoxy resin is also commonly referred to as a reactive diluent, and specific examples thereof include phenyl epoxidized propyl ether, cresyl epoxidized propyl ether, p-t-butylphenyl epoxidized ether, 2-B. Hexyl hexyl epoxidized propyl ether, butyl epoxidized propyl ether, C ₁₂ to C ₁₄ alcohol epoxidized propyl ether, butane diglycidyl ether, hexane diglycidyl ether, cyclohexane dimethyl epoxide The propyl ether, polyethylene glycol or polypropylene glycol is a matrix of glycidyl ether, etc., but is not limited thereto.

The mixing ratio of the polyvalent epoxy resin to the monovalent epoxy compound is not particularly limited. In the mass ratio, the polyvalent epoxy resin: the monovalent epoxy compound is preferably from 1:0 to 0.75, more preferably from 0.1 to 0.75.

The curing agent contained in the component (A) may, for example, be a curing agent or a curing accelerator used in a general epoxy resin. Specific examples thereof include an alkylimidazole compound such as 2-methylimidazole, 2-ethylimidazole, and 2-propylimidazole; an aryl imidazole compound such as phenylimidazole or naphthyl imidazole; and 2-aminoethyl group; Aminoalkylimidazole compound of imidazole, 2-aminopropylimidazole, etc.; hexamethylene dioxime, eicosanedioxime, 7,11-octadecane-1,18-bis(fluorenylcarbonyl) a ruthenium compound such as 1,3-bis(decylcarboxyethyl)-5-isopropylhydantoin; amidoximine, polyamine, dicyandiamide, tertiary phosphine, quaternary ammonium salt , quaternary salt, etc., but not limited to these. Further, two or more types (including two types) may be used in combination.

The above-mentioned hardener may be an epoxy group which is reacted with an epoxy resin represented by a bisphenol A type epoxy resin and a tertiary amine compound to the intermediate stage. Into a compound. In the present invention, a so-called epoxy-based latent latent hardener which is micropulverized to have a latent powder having an average particle diameter of 0.1 to 10.0 μm using the above epoxy group-adding compound can be lowered in room temperature. The activity is therefore preferred. A commercially available product can be used as the epoxy group-forming latent curing agent, and a commercially available product as an amine-epoxy group-forming hardening accelerator is a product name: Amicure PN-23, Amicure manufactured by Ajinomoto Co., Ltd. MY-24, Amicure MY-D, Amicure MY-H, etc.; ACR (share) manufactured by Harolder X-3615S, Hardener X-3293S, etc.; Asahi Kasei (stock) manufactured by No.: Novacure HX-3748, Novacure HX-3088, etc.; trade name manufactured by Pacific Anchor Chemical Co., Ltd.: Ancamine 2014AS, Ancamine 2014FG, etc.; Amine-urea plus form hardening accelerator is commercially available under the trade name: Fuji Chemical (trade): Fujicure FXE -1000, Fujicure FXE-1030, etc., but not limited to these.

The hardener is preferably added in an amount of 10 to 50% by weight based on the total of the component (A), and more preferably 15 to 30% by weight. In this range, the hardenability is sufficient, and the storage stability of the composition is also good.

The component (B) which can be used in the present invention is an elastomer. The conductivity under high temperature and high humidity is improved by containing the component (B). The component (B) is preferably dissolved in the epoxy resin for the user. The elastomer may be a copolymer containing an ethylene skeleton or a styrene skeleton, and from the viewpoint of compatibility with the component (A), an ethylene-vinyl acetate copolymer (EVA) may be mentioned. Specific examples of the elastomer of EVA include Levapren 500HV, 800HV, and 900HV manufactured by LANXESS Co., Ltd., and the vinyl acetate content in ethylene-vinyl acetate copolymer (EVA) is 50% by mass or more (including 50% by mass) is better, with 50 to More preferably, 90% by mass or more (including 90% by mass).

The amount of the component (B) to be added is preferably from 0.1 to 10 parts by mass, more preferably from 1 to 5 parts by mass, per 100 parts by mass of the component (A). When the component (B) is in such a range, it is preferable to suppress the change in the resistance value in the promotion test of the addition of the component (B), and the viscosity of the conductive composition is also appropriate.

The component (C) which can be used in the present invention is a rubber particle. By containing the component (C), the conductivity can be improved even under severe temperature changes. The component (C) is preferably dispersed in the component (A).

The average particle diameter of the rubber particles is preferably 0.05 to 0.5 μm. The method of measuring the average particle diameter is to observe the particles by an electron microscope, measure the particle diameters of 1000 arbitrary particles, and obtain a simple average value (number average). Here, the particle diameter of each particle is shown by the diameter when it is assumed to be a circle equal to the projected area. Further, rubber particles previously dispersed in the epoxy resin may also be used. Specifically, the rubber particles dispersed in the epoxy resin by a mixing device such as a hyper or homogenizer or the rubber particles synthesized by emulsion polymerization in the epoxy resin correspond to this. The rubber particles finally formed by the emulsion polymerization method preferably have an average particle diameter of 0.05 to 0.5 μm. By using the rubber particles previously dispersed in the epoxy resin, it is an advantage that the composition can be easily handled at the time of producing the resin composition. Further, since the epoxy resin and the rubber particles are sufficiently fused, there is a tendency that the change in viscosity over time is reduced.

Among the rubber particles, acrylic rubber particles are preferably used because they can be used in a wide variety of types. Specific examples of the acrylic rubber particles include, for example, MX series manufactured by Synthetic Chemical Co., Ltd.; manufactured by Mitsubishi Screw Co., Ltd. Metablen W series; ZEFIAC series manufactured by Gantz Kasei. Further, specific examples of the butadiene rubber particles include Metablen E series manufactured by Mitsubishi Screw Co., Ltd., and Metablen C series. Specific examples of the epoxy resin in which the rubber particles are dispersed in advance include, for example, the RKB series manufactured by Resinous Kasei Co., Ltd., and the like. Specific examples of the epoxy resin to be used in the emulsion polymerization include, for example, the Acryset BP series manufactured by Nippon Shokubai Co., Ltd., but are not limited thereto. Among the acrylic rubber particles, it is difficult to swell when added to the composition, and the change in viscosity of the composition is small with time and storage stability is good. Therefore, it can be dispersed in the component (A) without being dissolved in the component (A). The multilayer structure is preferred, and the core-shell type acrylic particles are more preferable.

The amount of the component (C) to be added is preferably from 1 to 50 parts by mass, more preferably from 5 to 25 parts by mass, per 100 parts by mass of the component (A). When the amount of the component (C) added is in this range, the effect of the present invention can be suitably obtained, and the conductive composition can be made to have a suitable viscosity.

The component (D) used in the present invention is a coupling agent. By adding the component (D), the resistance change of the composition can be suppressed even under severe conditions (under high temperature and high humidity conditions, under thermal cycling conditions). This is considered to be that the coupling agent improves the affinity between the epoxy resin and the conductive powder, and the adhesion between the adherend and the cured product and the connection reliability can be stabilized. As the coupling agent, a coupling agent such as a decane-based, titanium-based or aluminum-based coupling agent can be used. Among them, a decane-based coupling agent is preferred because it has a large variety and is more likely to improve the adhesion than other coupling agents. The decane coupling agent has at least one reactive functional group selected from the group consisting of an epoxy group, a methacryl group, an acryl group, and a vinyl group, and a hydrolyzable decane such as a trimethoxy sulfonyl group or a triethoxy hydrazine group. Compound. Specific examples of the decane coupling agent can be enumerated Such as: 3-glycidoxypropyltrimethoxy decane, 3-glycidoxypropyltriethoxy decane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxy decane, 3- Methyl propylene methoxy propyl trimethoxy decane, 3-methyl propylene methoxy propyl triethoxy decane, 3- propylene methoxy propyl trimethoxy decane, 3- propylene methoxy propyl triethoxy Decane, methacryloxymethyltrimethoxysilane, methacryloxymethyltriethoxysilane, propylene methoxymethyltrimethoxy decane, propylene methoxymethyltriethoxy decane, etc. Not limited to these. . Among them, a decane coupling agent having an epoxy group in its molecule is preferred from the viewpoint of curability and adhesion.

The amount of the component (D) to be added is preferably 0.1 to 10 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the component (A). When the amount of the component (D) added is within this range, the stability and adhesion of the electric resistance value in the test are promoted to be sufficient, and the effect of generating the unhardened component exhaust gas from the cured product is low, which is preferable.

The component (E) used in the present invention is a conductive powder. The conductive powder is not particularly limited, and the material of the particles and the shape of the particles are not particularly limited. Examples of the material of the particles include silver powder, nickel powder, palladium powder, carbon powder, tungsten powder, and plating powder. Examples of the shape of the particles include a spherical shape, a random shape, a sheet shape (scale shape), a filament shape (needle shape), and a resin shape. It can also be used by mixing a plurality of types. In particular, since the raw material is inexpensive, it is preferable to use a silver plating powder of a metal having an insulating metal oxide film, a nickel powder, and a silver plating powder of an insulator. In particular, the insulating oxidized metal may, for example, be copper powder, aluminum powder or iron powder, and the surface of the metal is non-dynamic, and the metal is not exhibited as a conductive composition. Further, examples of the insulator include insulating organic particles such as a polyacryl polymer or a polyethylene polymer. According to the constitution of the present invention, Even when the inexpensive conductive powder as described above is used, the conductivity of the conductive composition under high temperature and high humidity conditions and under thermal cycling conditions can be ensured. Among them, the increase in the resistance value over time and in the promotion of the test is remarkably suppressed, and the effect of the present invention can be more easily obtained. Therefore, the component (E) is a silver plating powder of a metal having an insulating metal oxide film. The nickel-plated powder and the silver-plated powder of the insulator are preferable, and the amount of the (E) component added to the conductive composition is lowered, and the initial conductivity is stabilized and the adhesion to the substrate is improved. It is preferred to use a silver-plated powder on the surface of the dendritic copper powder. Further, since the conductive powder having a spherical shape, a random shape, or a sheet shape (scaly shape) has good conductivity, the conductivity can be improved by combining the dendritic conductive powder. Therefore, the component (E) is preferably a mixed powder of a conductive powder containing a spherical shape, a random shape, or a sheet shape (scaly shape) and a dendritic conductive powder. The mass ratio of the spherical, random, sheet-like (scaly) conductive powder to the dendritic conductive powder is preferably from 1:0.1 to 10. In order to knead the resin component, the secondary aggregation powder is preferably 50 μm or less (including 50 μm). Specific examples of the plating powder include, for example, 10% silver plated CEE-1110 of dendritic silver-plated copper powder of Fukuda Metal Foil Powder Industry Co., Ltd.; SPC- of silver-plated copper powder of Deli Chemical Research Institute Co., Ltd. 423, SPC-425; ACGW-3 of spherical powder of silver-plated copper powder manufactured by Mitsui Mining & Mining Co., Ltd., ACBY-3 of dendritic powder, etc., but not limited to these. Further, specific examples of the nickel powder include 5005, 5010, 5020, 5050, 5080, 5100, etc. of spherical powder manufactured by Culox Technologies, and NF-32 and NF-40 of spherical powder manufactured by Toho Titanium Co., Ltd. NF-61, etc.; nickel powder 123 of spherical powder manufactured by Inco Limited; HCA-1 of sheet-like powder manufactured by Novamet, etc., but is not limited thereto.

The component (E) contains 40% by mass or more (including 40% by mass) of the entire conductive composition in order to exhibit conductivity. In the silver-plated powder having a low conductivity, the addition of 40% by mass or more (including 40% by mass) in the promotion test tends to be stable. Further, in consideration of the properties of the conductive composition, it is preferably 95% by mass or less (including 95% by mass). More preferably, the component (E) is 40 to 75% by mass based on the entire conductive composition.

In the conductive composition of the present invention, a coloring agent such as a pigment or a dye may be appropriately formulated within a range which does not impair the intended effect of the present invention; a plasticizer, an antioxidant, a defoaming agent, a solvent, an adhesive, Additives such as leveling agents, rheology control agents, and the like. By such addition, a composition excellent in properties, resin strength, adhesion strength, workability, and preservability, and a cured product thereof can be obtained.

The conductive composition of the present invention can be used as a conductive adhesive. Specifically, the adherends can be joined (cured) to each other by heat-hardening the adherends. For example, by wire coating or spot coating of the dispenser, it can be heat-hardened by placing (standing) in a hot air drying oven at 70 to 150 ° C environment. The joints for face-to-face bonding, the joints when the two materials of FIG. 1 are connected to the plane are used as joints for cross-linking, and when the two materials are joined at 90°, the joints are joined at an angle. form.

[Examples]

The invention is further illustrated by the following examples, but the invention is not limited to the examples.

[Examples 1 to 4 and Comparative Examples 1 to 4]

To prepare the conductive compositions of Examples 1 to 4 and Comparative Examples 1 to 4, the following components were prepared. Hereinafter, the conductive composition is simply referred to as a cured product of a composition or a composition, and is simply referred to as a cured product.

(A) component: hardenable epoxy resin

(a-1) Component: Epoxy resin

. Polyoxyalkylene bisphenol A epoxy propyl ether epoxy resin (Adeka resin EP-4000S ADEKA)

. Bisphenol F type epoxy resin (manufactured by EPICLON EXA-835LV DIC)

. 2-ethylhexylepoxypropyl ether (manufactured by EX-121 NAGASECHEMTEX Co., Ltd.)

(a-2) Ingredients: a hardener/amine-added latent hardener (average particle size: 5 μm) (manufactured by FUJICURE FXR-1030)

(B) Component: Elastomer

. Ethylene vinyl acetate copolymer (manufactured by LEVAPREN 800HV LANXESS) (ethylene/vinyl acetate = 20% by mass/80% by mass)

(C) component: rubber particles/core-shell type acrylic particles (60 mesh residuals: 0.1% or less (including 0.1%)) (ZEFIAC F351G Ganz Chemical Co., Ltd. manufactured average particle diameter 0.3 μm)

(D) Ingredients: coupling agent

. 3-glycidoxypropyltrimethoxy decane (KBM-403, Shin-Etsu Chemical Co., Ltd.)

(E) component: conductive powder

. Spherical silver-plated copper powder (average particle size 5 to 10 μm) (ACGW-3 Mitsui Metals) Mining (stock) manufacturing)

. Dendritic silver-plated copper powder (made by ACBY-3)

The raw material of the component (A) was weighed and stirred in a stirred tank. Then, the component (B) was added while heating and stirring for 1 hour. The temperature was lowered to room temperature, and the raw material (C) component, (D) component, and (E) component which satisfy the (a-2) hardener of (A) component were weighed, and it stirred further for 1 hour. The detailed dosage is based on Table 1, and the values are all expressed in parts by mass.

The content ratio of the component (E) is a value expressed by mass% of the component (E) with respect to the total of the components.

In the compositions of Examples 1 to 4 and Comparative Examples 1 to 4, viscosity measurement, volume resistance measurement, pencil scratch value confirmation, adhesion strength measurement, high-humidity high-temperature promotion test, and thermal cycle promotion test were performed. Return the result See Table 2.

[Viscosity measurement]

The viscosity of the composition was measured as "viscosity (Pa.s)" according to the following method.

Manufacturer; Dongji Industry (share) TV-33 viscometer (EHD type)

Determination conditions:

Conical rotor: 3° × R14

Rotation speed: 10.0 rpm

Measuring temperature: 25 ° C (for temperature adjustment device)

[Volume resistance measurement]

The glass plate having a length of 100 mm × a width of 100 mm and a thickness of 2.0 mm was shielded by a mask having a shape of 100 mm in length × 10 mm in width, and the composition was scraped off. At this time, the coating film was flat and the width of the mask was parallel to the test plate, taking care not to mix the bubbles into the composition. Finally, the mask was peeled off, and the composition was cured by heating at 90 ° C for 1 hour in a hot air drying oven to prepare a test piece. After the temperature of the test piece was lowered to room temperature, the "resistance (Ω)" when the distance between the electrodes (m) was 50 mm was measured using a test piece having an electrode having a width of 15 mm. Further, the thickness (m) of the cured product was measured by a thickness gage. Calculate the volume resistance (×10 ^-6 Ω.m) of the cured product according to Equation 1.

"Volume resistance (ρ)" = "resistance value (R)" × "sectional area (A)" / "interelectrode distance (L)"... Equation 1

ρ(×10 ^-6 Ω.m): volume resistance

R (Ω): resistance A (m ² ): sectional area (thickness of hardened material × 10 mm)

L(m): distance between electrodes

[pencil scratch value confirmation]

On a glass plate having a length of 100 mm × a width of 100 mm, a mask having a length of 100 mm × a width of 10 mm was shielded, and the composition was scraped off. At this time, the coating film was flat and the width of the mask was parallel to the test plate, taking care not to mix the bubbles into the composition. Finally, the mask was peeled off, and the composition was cured by heating at 90 ° C for 1 hour in a hot air drying oven to prepare a test piece. Use the pencil with the scratch value to confirm the "scratch value of the pencil (no unit)". The details are based on JIS K 5401.

[Follow strength measurement]

The glass plate having a length of 100 mm × a width of 100 mm and a thickness of 2.0 mm was shielded by a mask having a length of 100 mm × a width of 10 mm, and the composition was scraped off. At this time, the coating film was flat and the width of the mask was parallel to the test plate, taking care not to mix the bubbles into the composition. After the mask was peeled off, a ceramic piece of 1 mm φ was placed on the coating film, and the composition was cured by heating at 90 ° C for 1 hour in a hot air drying oven to prepare a test piece. After the temperature of the test piece of the composition was lowered to room temperature, the digital dynamometer was moved at a fixed speed in parallel with the glass plate, and the maximum strength of the peeled ceramic piece was measured. The "bonding strength (MPa)" of the cured product was calculated from the area under the ceramic sheet.

[High humidity and high temperature promotion test]

Two sheets of rectangular aluminum metal sheets of the same size were joined together with insulating tape on the side. Coating the metal to each other The composition of 5 mm φ was heated at 90 ° C for 1 hour to harden the composition, and a test piece as shown in Fig. 1 was produced. In the first drawing, the aluminum metal piece 2 is bonded to each other with an insulating tape 3, and the composition 1 is applied. The same test piece was produced even in the following thermal cycle promotion test. After the test piece was lowered to room temperature, the electrode of the test machine was pressed against the aluminum metal to measure the "initial resistance value (Ω)". Then, it was allowed to stand at 85 ° C × 85% RH for 100 hours. After the completion of the test, the test piece was taken out and returned to room temperature, and the "resistance resistance value (Ω)" was measured. In the high-temperature and high-humidity test, the difference between the resistance value after the promotion and the initial resistance value is referred to as "resistance value change 1 (Ω)", and is determined based on the following criterion.

Benchmark

○: 100 Ω or less (including 100 Ω)

△: greater than 100 Ω, and below 500 Ω (including 500 Ω)

×: greater than 500 Ω

[Thermal cycle promotion test]

After the test piece similar to the above test piece was produced in the high-temperature and high-humidity promotion test, the "initial resistance value (Ω)" was measured. The cycle of -40 ° C × 30 minutes and 90 ° C × 30 minutes was taken as one cycle, and the test piece was placed in 10 cycles and taken out. Then, after the test piece was returned to room temperature, the "resistance resistance value (Ω)" was measured. The difference between the post-promotion resistance value and the initial resistance value in the heat cycle test is referred to as "resistance value change 2 (Ω)", and is determined by the following criterion.

Benchmark

○: 100 Ω or less (including 100 Ω)

△: greater than 100 Ω, and below 500 Ω (including 500 Ω)

×: greater than 500 Ω

When the first embodiment and the comparative examples 2 to 4 of the present invention were compared, as is known, when either of the components (B) to (D) was not added, the conductivity was unstable in the promotion test. In the general conductive composition, if the silver powder is not added in an amount of 80% by mass or more (including 80% by mass), it is not stable. In the present invention, as described in Comparative Examples 1 to 4, it is known that the plating powder is 50% by mass or so. The volume resistance will be stable. Furthermore, the adherends of the resistance values 1 and 2 are aluminum, and the aluminum is oxidized by heat or water to form a non-dynamic surface to insulate the surface, and even if the surface of the composition is not dynamic, it promotes conductivity in the test. The reason for the deterioration is that the conductivity in the invention of the present invention is stable.

[Industrial Availability]

In the field of electronic components, aluminum alloy or stainless steel is used. Metals of various materials and metals have a highly oxidized metal, which may cause conduction failure in the conductive composition. However, the invention of the present invention can be expanded in a wide variety of electronic components that require stability and ensure continuity even in such a metal.

The present application is based on Japanese Patent Application No. 2012-083475, filed on Apr.

1‧‧‧Electrical composition

2‧‧‧Aluminum sheet

3‧‧‧Insulation tape

Claims (7)

The conductive composition contains the following components (A) to (E), and the component (E) contains 40% by mass or more (including 40% by mass) based on 100% by mass of the conductive composition, and the component (A): Curable epoxy resin (B) component: Elastomer (C) component: Rubber particle (D) component: Coupling agent (E) component: Conductive powder. The conductive composition according to the first aspect of the invention, wherein the component (A) contains an epoxy resin having one epoxy group in the molecule. The conductive composition according to claim 1 or 2, further comprising an epoxy group-forming latent curing agent. The conductive composition according to any one of claims 1 to 3, wherein the component (E) comprises a silver-plated powder having a surface of a dendritic copper powder. The conductive composition according to any one of claims 1 to 4, wherein the component (C) is a core-shell type acrylic particle. The conductive composition according to any one of claims 1 to 5, wherein the component (D) is a decane-based coupling agent having an epoxy group. A conductive adhesive comprising the conductive composition according to any one of claims 1 to 6.