JP2017066393A - Electrically conductive adhesive and electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrically conductive adhesive having good electrical conductivity and adhesion and being excellent in storage stability, and an electronic component formed by electrically connecting members with each other using the electrically conductive adhesive.SOLUTION: The electrically conductive adhesive and the like are provided. The electrically conductive adhesive comprises (A) a compound having ethylenically unsaturated bond, (B) a liquid peroxide, (C) silver powder, and (D) an organic binder. A blending amount of the compound (A) having an ethylenically unsaturated bond relative to the total mass of the conductive adhesive is, in terms of solids, 1 to 35 mass%. A blending amount of the liquid peroxide (B) relative to 100 pts.mass of the compound (A) having an ethylenically unsaturated bond is, in terms of solids, 0.1 to 20 pts.mass. A blending amount of the silver powder (C) relative to the total mass of the conductive adhesive is, in terms of solids, 65 mass% or more and less than 85 mass%. A blending amount of the organic binder (D) relative to the total mass of the conductive adhesive is, in terms of solids, 1 to 30 mass%. The conductive adhesive has a viscosity of 130 to 3000 dPa s.SELECTED DRAWING: None

Description

  The present invention relates to a conductive adhesive and an electronic component.

  As the density of printed wiring boards is increasing due to the recent reduction in size and size of electronic devices, as a technology used for electrical connection of electronic components, for example, electrical connection between wiring boards and electronic elements, and electrical connection between wiring boards Development and improvement of conductive adhesives are underway.

  Conventionally, in many conductive adhesives, epoxy resin is used as a binder component particularly from the viewpoint of adhesion, and conductive powder such as silver powder is used from the viewpoint of conductivity (for example, Patent Documents 1 and 2). However, when an epoxy resin is used, it tends to increase in viscosity, which causes a problem in storage stability. In addition, when a large amount of conductive powder is blended, the adhesiveness is deteriorated. On the other hand, when the blending amount of the conductive powder is reduced in order to improve the adhesiveness, the conductivity is deteriorated. There was room for.

JP 09-059586 A JP 2003-147279 A

  Accordingly, an object of the present invention is to provide a conductive adhesive having good conductivity and adhesion and excellent storage stability, and members are electrically connected using the conductive adhesive. To provide electronic components.

  As a result of intensive studies in view of the above, the present inventors have found that the above problems can be solved by blending a compound having an ethylenically unsaturated bond, a peroxide, and a certain amount or more of silver powder. It came to be completed.

  That is, the conductive adhesive of the present invention includes (A) a compound having an ethylenically unsaturated bond, (B) a liquid peroxide, (C) silver powder, and (D) an organic binder, (A) The compounding quantity of the compound which has an ethylenically unsaturated bond is 1-30 mass% with respect to the gross mass of a conductive adhesive in conversion of solid content, and the compounding quantity of the said (B) liquid peroxide is solid content. It is 0.1-20 mass parts with respect to 100 mass parts of (A) compound which has an ethylenically unsaturated bond in conversion, and the compounding quantity of the said (C) silver powder is the total mass of a conductive adhesive in solid content conversion. The blending amount of the organic binder (D) is 1 to 30% by mass with respect to the total mass of the conductive adhesive in terms of solid content, and the conductive adhesive. The viscosity is 130 to 3000 dPa · s. It is an.

  The conductive adhesive of the present invention is preferably used for conductive bonding of electronic components.

  The electronic component of the present invention is characterized in that members are electrically connected to each other using the conductive adhesive.

  According to the present invention, a conductive adhesive having good conductivity and adhesiveness and excellent storage stability, and an electronic device in which members are electrically connected using the conductive adhesive Parts can be provided.

  The conductive adhesive of the present invention includes (A) a compound having an ethylenically unsaturated bond, (B) liquid peroxide, (C) silver powder, and (D) an organic binder. And the compounding quantity of the compound which has the said (A) ethylenically unsaturated bond is 1-35 mass% with respect to the total mass of a conductive adhesive in conversion of solid content, and the said (B) liquid peroxide of The compounding amount is 0.1 to 20 parts by mass with respect to 100 parts by mass of the compound (A) having an ethylenically unsaturated bond in terms of solid content, and the compounding amount of the (C) silver powder is conductive in terms of solid content. It is 65 mass% or more and less than 85 mass% with respect to the total mass of an adhesive agent, and the compounding quantity of the said (D) organic binder is 1-30 mass% with respect to the total mass of a conductive adhesive in conversion of solid content. The viscosity as a conductive adhesive is 130 to 3000 dPa · s It is characterized in that. The conductive adhesive of the present invention can be suitably used as an isotropic conductive adhesive because it can be conductively bonded without applying pressure.

  Hereinafter, the components contained in the conductive adhesive of the present invention will be described in detail.

[(A) Compound having ethylenically unsaturated bond]
As the compound having an ethylenically unsaturated bond, a monofunctional or polyfunctional (meth) acryloyl group-containing compound can be preferably used. In the specification of the present application, the (meth) acryloyl group is a generic term for an acryloyl group and a methacryloyl group, and the same applies to other similar expressions.

  Examples of such (meth) acryloyl group-containing compounds include substituted or unsubstituted aliphatic acrylates, alicyclic acrylates, aromatic acrylates, heterocycle-containing acrylates, and ethylene oxide-modified acrylates, epoxy acrylates, aromatics thereof. Aromatic urethane acrylate, aliphatic urethane acrylate, polyester acrylate, polyether acrylate, polyol acrylate, alkyd acrylate, melamine acrylate, silicone acrylate, polybutadiene acrylate, and methacrylates corresponding to these can be used.

  More specifically, monofunctional (meth) acryloyl group-containing compounds include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) ) Acrylate, hydroxypropyl (meth) acrylate, butoxymethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, isodecyl (meth) acrylate, glycerol mono (meth) acrylate, etc. Cycloaliphatic (meth) acrylates such as acrylate, cyclohexyl (meth) acrylate, 4- (meth) acryloxytricyclo [5.2.1.02,6] decane, isobornyl (meth) acrylate, phenoxyethyl (meth) Aromatic (meth) acrylates such as acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and modified (meth) acrylates such as aliphatic epoxy-modified (meth) acrylate , Tetrahydrofurfuryl (meth) acrylate, (meth) acryloyloxyethylphthalic acid, γ- (meth) acryloxyalkyltrialkoxysilane, and the like can be used.

  Examples of the polyfunctional (meth) acryloyl group-containing compound include bisphenol-A-di (meth) acrylate, alkylene oxide-modified bisphenol-A-di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene Glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( ) Acrylate, bis [4- (meth) acryloxymethyl] tricyclo [5.2.1.02,6] decane, bis [4- (meth) acryloxy-2-hydroxypropyloxyphenyl] propane, isophorone diisocyanate modified Urethane (meth) acrylate, hexamethylene diisocyanate modified urethane (meth) acrylate, oligosiloxanyl di (meth) acrylate, trimethylhexamethylene diisocyanate modified urethane (meth) acrylate, triallyl isocyanurate, vinyl (meth) acrylate, allyl (meta ) Acrylate or the like can be used.

In addition, the following compounds can also be used.
(1) Liquid polybutadiene urethane (meth) acrylate obtained by subjecting 2-hydroxyethyl (meth) acrylate to a urethane addition reaction with a hydroxyl group of liquid polybutadiene via 2,4-tolylene diisocyanate,
(2) Liquid polybutadiene acrylate obtained by esterifying 2-hydroxyacrylate with maleated polybutadiene to which maleic anhydride has been added,
(3) Liquid polybutadiene (meth) acrylate obtained by dechlorination reaction between liquid polybutadiene having a hydroxyl group and (meth) acrylic acid chloride, and
(4) Liquid hydrogenated 1,2 polybutadiene (meth) acrylate obtained by modifying a liquid hydrogenated 1,2 polybutadiene glycol obtained by hydrogenating a double bond of a liquid polybutadiene having hydroxyl groups at both molecular ends with urethane (meth) acrylate.

  Examples of these commercially available products include NISSO PB TE-2000, NISSO PB TEA-1000, NISSO PB TE-3000, NISSOPB TEAI-1000 (all manufactured by Nippon Soda Co., Ltd.), MM-1000-80, MAC-1000. -80 (all manufactured by Nippon Petrochemical Co., Ltd.), Polybeck ACR-LC (manufactured by Nippon Hydrazine Kogyo Co., Ltd.), HYCAR VT VTR 2000 × 164 (manufactured by Ube Industries), Quinbeam101 (manufactured by Nippon Zeon Co., Ltd.), Chemlink 5000 (SARTOMER) Manufactured), BAC-15 (manufactured by Osaka Organic Chemical Industry Co., Ltd.), BAC-45 (manufactured by Osaka Organic Chemical Industrial Co., Ltd.), UAT-2000 (manufactured by Kyoeisha Chemical Co., Ltd.), Eporide PB-3600 (manufactured by Daicel Chemical Industries, Ltd.), EY RESIN, BR-45UAS ( Light chemical industry).

  Among such (meth) acryloyl group-containing compounds, in particular, 2-hydroxy-3-phenoxypropyl acrylate, phenoxyethyl acrylate, 4-hydroxybutyl acrylate, tetrahydrofurfuryl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl Acrylate, 2-acryloyloxyethyl phthalic acid, and aliphatic urethane acrylate are preferable, and 2-hydroxy-3-phenoxypropyl acrylate is more preferable.

  These compounds having an ethylenically unsaturated bond can be used alone or in combination.

  The compound having an ethylenically unsaturated bond as described above is preferably blended so that the ethylenically unsaturated bond equivalent in the organic component excluding the solvent of the composition is 260 or more. Preferably it is 260-1000, More preferably, it is 260-700, More preferably, it is 350-700, Most preferably, it is 350-550. By setting the ethylenically unsaturated bond equivalent to 260 or more, curing shrinkage that occurs during curing can be suppressed, and sufficient adhesion can be obtained. Moreover, sufficient sclerosis | hardenability can be acquired because an ethylenically unsaturated bond equivalent shall be 1000 or less. Here, the ethylenically unsaturated bond equivalent is a mass per gram equivalent per number of ethylenically unsaturated bonds. When the ethylenically unsaturated group is a (meth) acryloyl group, it is generally called a (meth) acrylic equivalent. For example, when the ethylenically unsaturated group is a (meth) acryloyl group, it is defined as the mass of an organic component (excluding the solvent when a solvent is included) per (meth) acryloyl group. That is, the ethylenically unsaturated bond equivalent can be obtained by dividing the total mass of organic components (excluding the solvent when a solvent is included) by the number of ethylenically unsaturated bonds in the composition.

  By using a peroxide described later as a polymerization initiator for such a compound having an ethylenically unsaturated bond, the reaction is quickly started, rapid curing becomes possible, and adhesion is improved.

  The compounding quantity of the compound which has an ethylenically unsaturated bond contains 1-35 mass% with respect to the total mass of a conductive adhesive in conversion of solid content. Preferably it is 1-30 mass%. By setting the blending amount of the compound having an ethylenically unsaturated bond to 1% by mass or more with respect to the total mass of the conductive adhesive, sufficient curability can be obtained and adhesion can be improved. Moreover, hardening shrinkage | contraction is suppressed and adhesiveness becomes favorable by making the compounding quantity of the compound which has an ethylenically unsaturated bond into 35 mass% or less with respect to the total mass of a conductive adhesive.

[(B) Liquid peroxide]
The conductive adhesive of the present invention contains a liquid peroxide as a polymerization initiator. Peroxide initiates a radical reaction of a compound having an ethylenically unsaturated bond. As a result, the compound having an ethylenically unsaturated bond is cured at a low temperature in a short time, and the adhesive force between members in the electronic component can be improved. Furthermore, it is excellent in storage stability. Here, the liquid peroxide means a peroxide that is liquid at room temperature (25 ° C.) and atmospheric pressure.

  Usually, in a thermosetting resin composition, a powder curing agent is blended to give a function as a latent curing agent, but when it contains a compound having the ethylenically unsaturated bond, Surprisingly, the storage stability of the conductive adhesive is further improved by using the liquid peroxide. As a result, according to the liquid peroxide, it is well dispersed in the conductive adhesive and acts well on the compound having an ethylenically unsaturated bond to promote curing.

  Examples of the liquid peroxide include ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, and acetylacetone peroxide, 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1, Peroxyketals such as 1-di (t-hexylperoxy) cyclohexane, 1,1-di (t-butylperoxy) -2-methylcyclohexane, and 1,1-di (t-butylperoxy) cyclohexane, 2,2-di (t-butylperoxy) butane, n-butyl 4,4-di- (t-butylperoxy) valerate, and 2,2-di (4,4-di- (t-butylperoxy) Peroxyketals such as oxy) cyclohexyl) propane, p-menthane hydroperoxide Hydroperoxides such as diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide, 2,5-dimethyl-2,5-di (T-butylperoxy) hexane, t-butylcumyl peroxide, di-t-hexyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-di (t-butylperoxy) ) Dialkyl peroxides such as hexyne-3, diisobutyl peroxide, di (3,5,5-trimethylhexanoyl) peroxide, di- (3-methylbenzoyl) peroxide, and benzoyl (3-methylbenzoyl) peroxide Diacyl peroxide such as di-n Peroxydicarbonates such as propylperoxydicarbonate, diisopropylperoxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, di-sec-butylperoxydicarbonate, cumylperoxyneodecanoate, 1,1 , 3,3-tetramethylbutylperoxyneodecanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxyneoheptanoate, t-hexylperoxy Pivalate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylper) Oxy) hexane, t-hexylperoxy-2-ethylhexanoe , T-butylperoxy-2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, t-butylperoxyacetate, t-butylperoxy-3-methylbenzoate, t-butylper Mention may be made of peroxyesters such as oxybenzoate and t-butylperoxyallyl monocarbonate, and 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone.

  Among these, preferable peroxides in the present invention include 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (t-hexylperoxy) cyclohexane, n- Peroxyketals such as butyl-4,4-di- (t-butylperoxy) valerate, hydroperoxides such as 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2, 5-di (t-butylperoxy) hexane, t-butylcumyl peroxide, di-t-hexyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butyl) Peroxy) 3-hexyne and other dialkyl peroxides, diacyl peroxides, peroxycarbonates, and 1,1,3, Tetramethylbutylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-hexylperoxyisopropylmonocarbonate, t -Butylperoxy-3,3,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, t-butylperoxy-3 -Peroxyesters such as methyl benzoate and t-butyl peroxybenzoate. Of the above preferred peroxides, di-t-hexyl peroxide, t-hexylperoxyisopropyl monocarbonate, 1,1-di (t-hexylperoxy) cyclohexane, 1,1,3, Use of 3-tetramethylbutylperoxy-2-ethylhexanoate is preferable in that excellent adhesion can be obtained.

  As the liquid peroxide as described above, a one-minute half-life temperature of 80 to 200 ° C, preferably 85 to 180 ° C is preferably used. By setting the half-life temperature for 1 minute to 80 ° C. or more, a sufficient pot life can be secured for use at room temperature. Moreover, sufficient sclerosis | hardenability is securable by making 1 minute half life temperature into 200 degrees C or less.

  The liquid peroxide can be used alone or in combination of a plurality of types.

  The compounding quantity of a liquid peroxide is suitably selected in 0.1-20 mass parts with respect to 100 mass parts of compounds which have an ethylenically unsaturated bond in conversion of solid content, Preferably it is 0.5-15 mass parts. . Sufficient curability can be ensured by setting the blending amount of the liquid peroxide to 0.1 parts by mass or more with respect to 100 parts by mass of the compound having an ethylenically unsaturated bond. Sufficient adhesion can be ensured by setting the blending amount of the liquid peroxide to 20 parts by mass or less with respect to 100 parts by mass of the compound having an ethylenically unsaturated bond.

[(C) Silver powder]
The conductive adhesive of the present invention contains 65% by mass or more and less than 85% by mass of silver powder with respect to the total mass of the conductive adhesive in terms of solid content. When it mix | blends within the said range, it will be easy to make a paste and adhesiveness will also become favorable. It does not specifically limit as silver powder, For example, a spherical shape, flake shape, and a chain-like thing can be used. Here, the flake shape includes a flat plate shape, a thin rectangular parallelepiped shape, a flake shape, and a scale shape, and means a shape having an aspect ratio (average major axis / average thickness) larger than 1.5. The aspect ratio can be obtained by (average major axis L / average thickness T). Here, the “average major axis L” and the “average thickness T” indicate the average major axis and average thickness of 30 flaky silver powders measured with a scanning electron microscope. In addition, the chain shape specifically includes aggregated silver powder or silver particles branched into branches, that is, dendritic silver powder. In the present invention, since the resistance value can be further reduced, the silver powder is preferably flaky.

  As a commercial item of the said flaky silver powder, AgC-A (made by Fukuda Metal Foil Powder Industry), AA-4703 (made by Metal Technologies USA), FA-D-5, FA-D-7 (or more, DOWA Electronics Co., Ltd.).

  The average particle diameter of the silver powder is the average particle diameter of 10 random silver powders observed at 10,000 times using an electron microscope (SEM), and the range is preferably 0.5 to 30 μm. .

[(D) Organic binder]
The conductive adhesive of the present invention further contains an organic binder. The organic binder is other than the compound having the ethylenically unsaturated bond. By adding an organic binder, stress generated during thermosetting can be relieved and adhesion can be further improved.

  The organic binder is an organic resin component, and publicly known and commonly used natural resins and synthetic resins can be used. As such an organic binder, natural resins such as cellulose and rosin, polyethylene, polypropylene, polystyrene, polycarbonate, polyvinyl chloride, polyvinyl acetate, polyamide, acrylic resin, polyethylene terephthalate, fluororesin, silicon resin, polyester resin, Synthetic resins such as acetal resin and butyral resin can be used. Of these, acrylic resins, butyral resins, and saturated polyester resins are preferably used, and saturated polyester resins are more preferable.

  Specific examples of the acrylic resin include Clarity LA2330 of Clarity series (Kuraray).

  Specific examples of butyral resins include Sekisui Chemical S Lec Series (manufactured by Sekisui Chemical Co., Ltd.), S-LEC BL-1, BL-1H, BL-2, BL-2H, BL-5, BL-10, BL-10, BL-S, BL-L, etc. are mentioned.

  As specific examples of the saturated polyester resin, Byron 200, 220, 240, 245, 270, 280, 290, 296, 300, 337, 500, 530, 550, 560, 600 of Toyobo Byron series (manufactured by Toyobo Co., Ltd.) 630, 650, BX1001, GK110, 130, 140, 150, 180, 190, 250, 330, 590, 640, 680, 780, 810, 880, 890, and the like.

  The organic binder is preferably a solid at room temperature (25 ° C.) and atmospheric pressure. By using a solid organic binder, it becomes easy to maintain the strength after curing of the conductive adhesive. The Tg (glass transition temperature) of the organic binder is -20 to 150 ° C, preferably 0 to 120 ° C, more preferably 2 to 70 ° C.

  The molecular weight of the organic binder is 1,000 to 100,000, preferably 3,000 to 80,000, more preferably 5,000 to 60,000. If the molecular weight is 1,000 or more, the stress can be relaxed without bleeding out at the time of curing, and if it is 100,000 or less, it is easily compatible with a compound having an ethylenically unsaturated bond to obtain sufficient fluidity. be able to.

  The compounding quantity of an organic binder contains 1-30 mass% with respect to the total mass of a conductive adhesive in conversion of solid content. Preferably it is 3-25 mass%.

  The conductive adhesive of the present invention preferably contains no epoxy resin from the viewpoint of stability. Here, “does not contain an epoxy resin” means that it is not actively blended as a constituent component, and it is not excluded that it is contained in a small amount within a range that does not impair the effects of the present invention. For example, it is 1 mass% or less with respect to the total mass of a conductive adhesive, Preferably it is 0 mass%.

  The conductive adhesive of the present invention preferably contains no solvent. In the present invention, “no solvent is used” means that the conductive adhesive is substantially free of solvent, and the mass of the conductive adhesive after heating at 130 ° C. for 30 minutes is compared with the mass before heating. And 3% by mass or less.

  The conductive adhesive of the present invention can contain additives such as known and commonly used thixotropy imparting agents, wetting and dispersing agents, antifoaming agents, and leveling agents, if necessary.

  As the thixotropic agent, bentonite, wax, metal stearate, modified urea, silica and the like can be used. Among these, silica is preferable. The silica is preferably amorphous silica, more preferably amorphous silica having an average primary particle diameter of 50 nm or less, and particularly preferably hydrophobic amorphous silica having a hydrophobic surface.

  As the wetting and dispersing agent, aliphatic carboxylic acids, aliphatic carboxylates, higher alcohol sulfates, alkyl sulfonic acids, phosphate esters, polyethers, polyester carboxylic acids and their salts can be used. Of these, phosphate esters are preferred.

  As the antifoaming agent, silicone resin, modified silicone resin, organic polymer polymer, organic oligomer, and the like can be used. Among these, organic polymer polymers and organic oligomers are preferred, and vinyl ether polymers are more preferred.

  The viscosity of the conductive adhesive of the present invention is 130 to 3000 dPa · s or less. The viscosity here is a value of 30 seconds at 25 ° C. and 5 rotations measured by a rotary viscometer. When the viscosity is 130 dPa · s or more, the viscosity is not too low and workability is good, and sagging hardly occurs. On the other hand, when it is 3000 dPa · s or less, the coating film surface is smooth when printed and air bubbles are easily removed, so that stable adhesion and conductivity can be easily obtained.

  The viscosity is measured with a cone plate viscometer composed of a cone rotor (conical rotor) and a plate described in JIS Z 8803, for example, TV-30 type (manufactured by Toki Sangyo, rotor 3 ° × R9.7). The

  The conductive adhesive of the present invention can be used for electrical connection between members in an electronic component. For example, it can be used for electrical connection between a printed wiring board and an electronic element and electrical connection between printed wiring boards, and in particular, for electrical connection between a rigid printed wiring board or a flexible printed wiring board and an electronic component. It is preferable. Moreover, it can use suitably also for the electrical connection in a smart phone, a tablet terminal, a wearable terminal, and lighting equipment. Furthermore, since it is excellent in electromagnetic shielding characteristics, it can be suitably used for electrical connection in electronic equipment that requires electromagnetic shielding characteristics.

  The method for applying the conductive adhesive according to the present invention is not particularly limited. For example, the conductive adhesive of the present invention is applied to the electrical connection portion of the connection member in a printed wiring board or the like using a screen mesh or a metal mask, Or it can apply | coat with coating apparatuses, such as a dispenser.

  After confirming that the conductive adhesive has been sufficiently supplied to the connection location, the member to be connected (component) is placed on the connection location of the connection member (substrate) and cured by heating to a predetermined temperature. Thereby, a connection member (board | substrate) and a to-be-connected member (component) can be electrically connected.

  The heating temperature is 50 to 240 ° C., preferably 70 to 180 ° C., more preferably 90 to 160 ° C., and the heating time is 1 to 60 minutes, preferably 1 to 20 minutes, more preferably 1 to 10 minutes. . When processing at a temperature of 50 ° C or higher, the thermal reaction proceeds satisfactorily, and by performing the processing at a temperature of 240 ° C or lower, the electronic performance of the bonding target is not damaged by heating, and the original performance is achieved. Hold. In addition, by setting the heating time to a short time, damage to the electronic component due to heat can be avoided. The thickness of the electrically connected portion after heating is not particularly limited as long as it can be adhered.

  Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto. In the following description, “part” and “%” are based on mass unless otherwise specified.

(Examples 1-1 to 1-7, 2-1 to 2-7 and Comparative Examples 1-1 to 1-6, 2-1 to 2-3)
(Preparation of conductive adhesive)
Each component was blended and stirred at a blending ratio (mass ratio) shown in Tables 1 to 4 to prepare conductive adhesives of Examples and Comparative Examples.

(Evaluation of resistance value)
The conductive adhesives of Examples and Comparative Examples were applied on a PET substrate (Lumirror 125E20 manufactured by Toray Industries, Inc.) with a scraper through a metal mask (mask thickness: 140 μm, opening: 8 × 15 mm solid). Next, the coated substrate was put into a hot air circulation dryer under conditions of curing temperature: 130 ° C. and curing time: 5 minutes to cure the coating film, and an 80 μm coating film was obtained after curing. The 8 × 15 mm solid resistance value measured from both ends of the cured 8 × 15 mm solid coating film using a tester (Milliohm High Tester 3540, manufactured by Hioki Electric Co., Ltd.) was evaluated as a resistance value.

(Evaluation of adhesion)
The conductive adhesives of Examples and Comparative Examples were applied on a PET substrate (Lumirror 125E20 manufactured by Toray Industries, Inc.) with a scraper through a metal mask (mask thickness: 140 μm, opening: 8 × 15 mm solid). Next, a hexagonal nut plated with electroless gold on the applied pattern (with a screw hole in the center, contact area: 14.2 mm ² , thickness: 2 mm), lightly tapped 2-3 times, and curing temperature : 130 ° C., curing time: put into a hot-air circulating drier under the conditions of 5 minutes to cure the coating film, and obtain a coating film of 80 μm after curing. After curing, a tape peel was applied from above the nut, and adhesion was evaluated according to the following evaluation criteria.
○: not peeled ×: peeled

(Evaluation of storage stability)
20 g of each of the conductive adhesives of Examples and Comparative Examples was placed in a plastic container and stored for 60 hours in a thermostatic bath at 30 ° C., then the state of the paste was confirmed, and the adhesion was evaluated according to the following evaluation criteria. In addition, about conductive adhesives other than Comparative Examples 1-2, 1-4, 2-1 to 2-3, 20 g of each was put into a plastic container and the paste after being stored in a thermostatic bath at 30 ° C. for 240 hours. The state was also confirmed.
○: Not gelled Δ: Partially gelled ×: Gelled

＊１：２−ヒドロキシ−３−フェノキシプロピルアクリレート（東亜合成社製アロニックスＭ−５７００）、分子量：２２２、Ｔｇ：１７℃、粘度：１．６５ｄＰａ・ｓ／２５℃）
＊２：飽和ポリエステル樹脂（東洋紡社製バイロン５００）、分子量：２３，０００、Ｔｇ：４℃
＊３：ビスフェノールＡ型エポキシ樹脂（三菱化学社製８２８）、分子量：３７０、粘度：１３８ｄＰａ・ｓ／２５℃
＊４：２-エチル−４−メチルイミダゾール（四国化成工業社製２Ｅ４ＭＺ）
＊５：フレーク状銀粉（福田金属箔粉工業社製：ＡｇＣ−Ａ）、平均粒径：３．５μｍ（ＳＥＭ）
＊６：ジ−ｔ−へキシルパーオキサイド（日油社製パーへキシルＤ）、性状：液状、１分間半減温度：１７６．７℃、１０時間半減温度：１１６．４℃
＊７：ｔ−へキシルパーオキシイソプロピルモノカーボネイト（日油社製パーへキシルＩ）、性状：液状、１分間半減温度：１５５．０℃、１０時間半減温度：９５．０℃
＊８：１，１−ジ（ｔ−へキシルパーオキシ）シクロヘキサン（日油社製パーヘキサＨＣ）、性状：液状、１分間半減温度：１４９．２℃、１０時間半減温度：８７．１℃
＊９：１，１，３，３−テトラメチルブチルパーオキシ−２−エチルヘキサノエート（日油社製パーオクタＯ）、性状：液状、１分間半減温度：１２４．３℃、１０時間半減温度：６５．３℃
＊１０：ジベンゾイルパーオキサイド（日油社製ナイパーＢＷ）、性状：粉状、１分間半減温度：１３０℃、１０時間半減温度：７３．６℃
＊１１：ジ（４−ｔ−ブチルシクロへキシル）パーオキシジカーボネート（日油社製パーロイルＴＣＰ）、性状：粉状、１分間半減温度：９２．１℃、１０時間半減温度：４０．８℃）

* 1: 2-hydroxy-3-phenoxypropyl acrylate (Aronix M-5700, manufactured by Toa Gosei Co., Ltd., molecular weight: 222, Tg: 17 ° C., viscosity: 1.65 dPa · s / 25 ° C.)
* 2: Saturated polyester resin (byron 500 manufactured by Toyobo Co., Ltd.), molecular weight: 23,000, Tg: 4 ° C
* 3: Bisphenol A type epoxy resin (828, manufactured by Mitsubishi Chemical Corporation), molecular weight: 370, viscosity: 138 dPa · s / 25 ° C.
* 4: 2-Ethyl-4-methylimidazole (2E4MZ manufactured by Shikoku Chemicals)
* 5: Flake-like silver powder (Fukuda Metal Foil Powder Industry Co., Ltd .: AgC-A), average particle size: 3.5 μm (SEM)
* 6: Di-t-hexyl peroxide (Perhexyl D manufactured by NOF Corporation), properties: liquid, 1 minute half temperature: 176.7 ° C., 10 hour half temperature: 116.4 ° C.
* 7: t-Hexylperoxyisopropyl monocarbonate (Perhexyl I, NOF Corporation), property: liquid, 1 minute half temperature: 155.0 ° C, 10 hour half temperature: 95.0 ° C
* 8: 1,1-di (t-hexylperoxy) cyclohexane (Perhexa HC manufactured by NOF Corporation), properties: liquid, 1 minute half temperature: 149.2 ° C., 10 hour half temperature: 87.1 ° C.
* 9: 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Perocta O manufactured by NOF Corporation), properties: liquid, 1 minute half temperature: 124.3 ° C., 10 hour half temperature : 65.3 ° C
* 10: Dibenzoyl peroxide (Nippa Niper BW), properties: powder, 1 minute half temperature: 130 ° C., 10 hours half temperature: 73.6 ° C.
* 11: Di (4-t-butylcyclohexyl) peroxydicarbonate (Perroyl TCP manufactured by NOF Corporation), property: powder, 1 minute half temperature: 92.1 ° C, 10 hour half temperature: 40.8 ° C )

＊１２：未評価

* 12: Not evaluated

  As shown in the said table | surface, it turns out that the electroconductive adhesive agent of Examples 1-1 to 1-7 has favorable electroconductivity and adhesiveness, and is excellent in storage stability. On the other hand, in Comparative Examples 1-1 and 1-2 using powdered peroxide, storage stability was not obtained. In the conductive adhesive of Comparative Example 1-3 in which the blending amount of the silver powder was less than 65% by mass, conductivity was not obtained. Moreover, it turns out that the conductive adhesive of Comparative Example 1-4 using an epoxy resin is inferior in storage stability. The conductive adhesive of Comparative Example 1-5 containing no peroxide had a high resistance value and poor adhesion. The 1-6 conductive adhesive containing no organic binder was inferior in adhesion.

  As shown in the said table | surface, it turns out that the conductive adhesive of Examples 2-1 to 2-7 has favorable electroconductivity and adhesiveness, and is excellent in storage stability. On the other hand, in the conductive adhesive of Comparative Example 2-1, in which the amount of silver powder was less than 65% by mass, no conductivity was obtained. Moreover, it turns out that the conductive adhesive of Comparative Example 2-2 using an epoxy resin is inferior in storage stability. The conductive adhesive of Comparative Example 2-3 containing no peroxide had a high resistance value and poor adhesion.

Claims (3)

(A) a compound having an ethylenically unsaturated bond;
(B) liquid peroxide;
(C) silver powder;
(D) an organic binder, and a conductive adhesive comprising:
(A) The compounding quantity of the compound which has an ethylenically unsaturated bond is 1-35 mass% with respect to the total mass of a conductive adhesive in conversion of solid content, and the compounding quantity of the said (B) liquid peroxide is solid. It is 0.1-20 parts by mass with respect to 100 parts by mass of the compound (A) having an ethylenically unsaturated bond in terms of minutes, and the blending amount of the (C) silver powder is the total amount of the conductive adhesive in terms of solids. It is 65 mass% or more and less than 85 mass% with respect to mass, The compounding quantity of the said (D) organic binder is 1-30 mass% with respect to the total mass of a conductive adhesive in conversion of solid content, and conductive adhesion A conductive adhesive having a viscosity of 130 to 3000 dPa · s as an agent.   The conductive adhesive according to claim 1, which is used for conductive bonding of electronic parts.   An electronic component, wherein members are electrically connected using the conductive adhesive according to claim 1.