JPH10273540A - Anisotropic, electrically conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anisotropic, electrically conductive film, which can be produced by curing for a short time at a low temperature and is excellent in processability, transparency, adhesiveness and durability, and in which the conductivity in thickness direction and the insulation in plane direction are both maintained even after it has been allowed to stand under a high temperature atmosphere for a long time. SOLUTION: In an anisotropic, electrically conductive film, wherein an adhesive contains electrically conductive particles dispersed therein and electrical conductivity is caused in thickness direction by applying a pressure in the direction, the adhesive comprises (A) an ethylene-vinyl acetate copolymer, (B) a copolymer of ethylene, vinyl acetate and an acrylate and/or methacrylate monomer, (C) a copolymer of ethylene, vinyl acetate and maleic acid and/or maleic anhydride, (D) a copolymer of ethylene, an acrylate and/or methacrylate monomer and maleic acid and/or maleic anhydride, and (E) an ionomer resin wherein molecules of an ethylene-methacrylic acid copolymer are bonded between them through a metal ion, as main components, and further comprises (F) an acrylic monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of interposing circuits between opposing circuits, applying pressure and heating between the circuits to connect the circuits via conductive particles, and bonding and fixing the circuits. The present invention relates to an anisotropic conductive film that provides conductivity only in the thickness direction and is used for the purpose.

[0002]

2. Description of the Related Art Anisotropic conductive films are used for flexible printed circuit (FPC).
And TAB and IT formed on the glass substrate of the liquid crystal panel
It is used when an anisotropic conductive film is formed between various terminals, such as when connecting to an O terminal, thereby bonding and electrically connecting the terminals.

[0003] Anisotropic conductive films are generally obtained by dispersing conductive particles in an adhesive mainly composed of an epoxy or phenolic resin and a curing agent. One-component thermosetting type is becoming mainstream. In addition, in order to obtain stable connection reliability even under high temperature and high humidity, the bonding strength of the anisotropic conductive film is enhanced by various methods.

However, conventional anisotropic conductive films using epoxy or phenolic resins have low adhesive strength,
Workability was poor.

An object of the present invention is to provide an anisotropic conductive film which is improved in the above circumstances, cures in a short time at a low temperature, has good workability, has a high crosslinking density, and has excellent durability. And

[0006]

Means for Solving the Problems and Embodiments of the Invention In order to achieve the above object, the present invention comprises a method in which conductive particles are dispersed in an adhesive, and the pressure is applied in the thickness direction to thereby increase the thickness in the thickness direction. In the anisotropic conductive film provided with conductivity, the adhesive is (A) an ethylene-vinyl acetate copolymer,
(B) a copolymer of ethylene and vinyl acetate with acrylate and / or methacrylate monomers, (C) a copolymer of ethylene with vinyl acetate and maleic acid and / or maleic anhydride, and (D) a copolymer of ethylene and acrylate Copolymer of maleic acid and / or maleic anhydride with a monomer and / or methacrylate monomer, and (E) ethylene-
It is a heat- or photo-curable adhesive containing a polymer selected from ionomer resins in which the molecules of a methacrylic acid copolymer are bonded with metal ions as a main component and further adding an acrylic monomer (F). To provide an anisotropic conductive film.

[0007] The anisotropic conductive film of the present invention is a heat or light curable adhesive containing the above polymer as a main component as an adhesive and further adding an acrylic monomer containing no highly reactive epoxy group. It has the following features. (1) Even after being held at a high temperature for a long time, the properties of the anisotropic conductive film are effectively exhibited and the durability is excellent. (2) Good repairability. (3) Good transparency. (4) Stable and high adhesiveness is exhibited as compared with conventional products. (5) By using a film made of the transparent polymer as a raw material, light transmittance at the time of electrode positioning is good. (6) It can be cured at a low temperature in a short time, and has good workability. (7) Conventional products such as epoxy resins require heating at 150 ° C. or higher, but according to the present invention, they can be cured and bonded at 130 ° C. or lower, particularly 120 ° C. or lower, and have UV curability. Therefore, curing and bonding at a lower temperature are also possible. (8) The conventionally used epoxy-based and phenol-based anisotropic conductive films have no tackiness, and the film is difficult to temporarily fix to the electrode by the adhesive force, easily peeled off, and has poor workability. Since the anisotropic conductive film has high adhesive strength at the time of temporary fixing, workability is good.

Hereinafter, the present invention will be described in more detail.
The anisotropic conductive film of the present invention is obtained by dispersing conductive particles in an adhesive. In this case, the adhesive mainly contains a polymer selected from the following (A) to (E). And an acrylic monomer containing no epoxy group is used. (A) Ethylene-vinyl acetate copolymer (B) Copolymer of ethylene and vinyl acetate with acrylate and / or methacrylate monomers (C) Copolymer of ethylene with vinyl acetate and maleic acid and / or maleic anhydride Polymer (D) Copolymer of ethylene, acrylate-based and / or methacrylate-based monomer, maleic acid and / or maleic anhydride (E) Ionomer in which ethylene-methacrylic acid copolymer molecules are bonded by metal ions resin

When an ethylene-vinyl acetate copolymer is used as the polymer, the ethylene-vinyl acetate copolymer preferably has a vinyl acetate content of 10 to 50% by weight, more preferably 15 to 45% by weight. is there. When the vinyl acetate content is less than 10% by weight, a sufficient degree of crosslinking cannot be obtained when crosslinking and curing at a high temperature. On the other hand, when the content exceeds 50% by weight, the softening temperature of the resin becomes low, and the storage becomes difficult. It is a problem.

When a copolymer of ethylene, vinyl acetate and acrylate and / or methacrylate monomers is used as the polymer, the vinyl acetate content of the copolymer is preferably 10 to 50% by weight. , More preferably 14 to 45% by weight. When the vinyl acetate content is less than 10% by weight, a sufficient degree of crosslinking cannot be obtained when crosslinking and curing at a high temperature. On the other hand, when the content exceeds 50% by weight, the softening temperature of the resin becomes low, and the storage becomes difficult. It is a problem. Further, the content of the acrylate and / or methacrylate monomer in the copolymer is preferably 0.01 to 10% by weight, and more preferably 0.05 to 5% by weight. When the content of the monomer is less than 0.01% by weight, the effect of improving the adhesive strength is reduced, while when it exceeds 10% by weight, the processability may be reduced.

The acrylate and / or methacrylate monomers that can be used are monomers selected from acrylate or methacrylate monomers, and include acrylic acid or methacrylic acid and one having 1 carbon atom.
Preferred are esters with substituted aliphatic alcohols having an unsubstituted or substituted substituent such as an epoxy group, such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, and glycidyl methacrylate. Is mentioned.

Further, when a copolymer of ethylene, vinyl acetate, maleic acid and / or maleic anhydride is used as the polymer, the vinyl acetate content of the copolymer is preferably 10 to 50% by weight. , More preferably 14 to 45% by weight. If the vinyl acetate content is less than 10% by weight, a sufficient degree of crosslinking cannot be obtained when crosslinking and curing at a high temperature, while if it exceeds 50% by weight, the strength and durability of the adhesive layer tend to be significantly reduced. Become. Further, the content of maleic acid and / or maleic anhydride in the copolymer is preferably from 0.01 to 10% by weight, more preferably from 0.05 to 5% by weight. If the content is less than 0.01% by weight, the effect of improving the adhesive strength is reduced, while if it exceeds 10% by weight, the workability may be reduced.

When a copolymer of ethylene, acrylate and / or methacrylate monomers and maleic acid and / or maleic anhydride is used as the polymer,
The acrylate monomer content of this copolymer is 10
To 50% by weight, more preferably 1 to 50% by weight.
4 to 45% by weight. If the content of the acrylate monomer is lower than 10% by weight, a sufficient degree of crosslinking cannot be obtained when crosslinking and curing at a high temperature, while if it exceeds 50% by weight, the strength and durability of the adhesive layer are significantly reduced. It becomes a tendency. Further, the content of maleic acid and / or maleic anhydride in the copolymer is preferably from 0.01 to 10% by weight, more preferably from 0.05 to 5% by weight. If the content is less than 0.01% by weight, the effect of improving the adhesive strength is reduced, while if it exceeds 10% by weight, the workability may be reduced.

The acrylate and / or methacrylate monomers include the same ones as described above.

When an ionomer resin in which the molecules of an ethylene-methacrylic acid copolymer are bonded with metal ions (hereinafter referred to as “ethylene-methacrylic acid ionomer resin”) is used as the polymer, the methacrylic acid content of the resin is 1%. It is preferably from 30 to 30% by weight, more preferably from 5 to 25% by weight. If the methacrylic acid content is less than 1% by weight, the ionic crosslinking effect is reduced, and the adhesive strength is reduced. On the other hand, if the methacrylic acid content exceeds 30% by weight, the workability may be significantly reduced.

The metal ions used in the ethylene-methacrylic acid ionomer resin include metal cations such as sodium, zinc, magnesium and lithium, and the degree of ionization by the metal ions is 5 to 80%. Preferably, it is more preferably 7 to 70%. If the degree of ionization is less than 5%, the transparency is significantly reduced, and if it exceeds 80%, the workability may be significantly reduced.

To the anisotropic conductive film of the present invention, an acrylic monomer containing no epoxy group and no silicon atom is added for the workability of curing at a low temperature in a short time.

The acrylic monomers that can be used include:
For example, isoamyl acrylate, lauryl acrylate, stearyl acrylate, butoxyethyl acrylate, ethoxydiethylene glycol acrylate, methoxytriethylene glycol acrylate, methoxypolyethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate, phenoxy polyethylene glycol acrylate, tetrahydrofurfuryl acrylate, Isobornyl acrylate, 1-hydroxyethyl acrylate, isooctyl acrylate, isomyristyl acrylate, isostearyl acrylate, 2-ethylhexyl diglycol acrylate, 2-hydroxybutyl acrylate, polytetramethylene glycol diacrylate, EO-modified Methylolpropane triacrylate, perfluorooctylethyl acrylate, trimethylolpropane triacrylate, EO-modified trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, neopentyl glycol acrylate benzoate, Examples include triethylene glycol diacrylate, polyethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, dimethylol tricyclodecane diacrylate, and the like.

As these acrylic monomers, at least one of them is used alone or in combination, and usually 0.1 to 60 parts by weight based on 100 parts by weight of the polymer.
Parts by weight, preferably 1 to 30 parts by weight, more preferably 1 to 30 parts by weight.
２５25 parts by weight are used. If the amount is less than 0.1 part by weight, desired workability cannot be obtained, and if it is more than 60 parts by weight, the adhesive strength may be reduced.

As the conductive particles used in the present invention, various types can be used as long as they are electrically good conductors. For example, metal powder such as copper, silver, and nickel, resin or ceramic powder coated with such a metal can be used. There is no particular limitation on the shape, and any shape such as a scale shape, a tree shape, a granular shape, and a pellet shape can be adopted.

In the present invention, the compounding amount of the conductive particles is
The content is preferably 0.1 to 15% by volume based on the polymer, and the average particle size is preferably 0.1 to 100 µm. In this way, by defining the blending amount and the particle size, the conductive particles are condensed between adjacent circuits and short circuit is prevented.

For curing the anisotropic conductive film of the present invention, an organic peroxide or a photosensitizer can be used. When the curable adhesive is a thermosetting adhesive, Usually, when an organic peroxide is used and the curable adhesive is a photocurable adhesive, a photosensitizer is usually used.

As the organic peroxide added for curing the anisotropic conductive film of the present invention, any organic peroxide which can be decomposed at a temperature of 70 ° C. or more to generate radicals can be used. The decomposition temperature with a half-life of 10 hours is preferably 50 ° C. or higher, and is selected in consideration of the film formation temperature, preparation conditions, curing (bonding) temperature, heat resistance of the adherend, and storage stability.

Examples of usable organic peroxides include 2,5-dimethylhexane-2,5-dihydroperoxide and 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne- 3, di-t-butyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane,
Dicumyl peroxide, α, α′-bis (t-butylperoxyisopropyl) benzene, n-butyl-4,
4′-bis (t-butylperoxy) valerate, 1,
1-bis (t-butylperoxy) cyclohexane,
1,1-bis (t-butylperoxy) -3,3,5-
Trimethylcyclohexane, t-butylperoxybenzoate, benzoyl peroxide, t-butylperoxyacetate, methylethylketone peroxide, 2,5-dimethylhexyl-2,5-bisperoxybenzoate, butylhydroperoxide, p-
Menthane hydroperoxide, p-chlorobenzoyl peroxide, hydroxyheptyl peroxide, chlorohexanone peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, cumyl peroxy octoate, succinic acid peroxide, acetyl peroxide Oxide, t-butylperoxy (2-ethylhexanoate), m-toluoyl peroxide, t-butylperoxyisobutyrate, 2,4-dichlorobenzoyl peroxide and the like. As organic peroxides,
At least one of these is used alone or in combination, and usually 0.1 to 1 part by weight based on 100 parts by weight of the polymer.
0 parts by weight are used.

As the photosensitizer (photopolymerization initiator) added for curing the anisotropic conductive film of the present invention, a radical photopolymerization initiator is suitably used. Among the radical photopolymerization initiators, benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4′-methyldiphenylsulfide, isopropylthioxanthone, diethylthioxanthone, ethyl 4- (diethylamino) benzoate and the like are examples of hydrogen abstraction initiators. Can be used. Further, among the radical photopolymerization initiators, benzoin ether, benzoyl propyl ether, benzyl dimethyl ketal, and α-hydroxyalkylphenone are used as intramolecular cleavage initiators as 2-hydroxy-2-methyl- as α-hydroxyalkylphenone type.
1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, alkylphenylglyoxylate, diethoxyacetophenone, and 2-methyl-1- [4
-(Methylthio) phenyl] -2-morpholinopropanone-1,2-benzyl-2-dimethylamino-1-
(4-morpholinophenyl) butanone-1 and acylphosphine oxide are used. As the photosensitizer, at least one of them is used alone or as a mixture, and usually 0.1 to 10 parts by weight is added to 100 parts by weight of the polymer.

It is preferable to add a silane coupling agent as an adhesion promoter to the anisotropic conductive film of the present invention. Examples of the silane coupling agent include vinyl tris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane,
γ-glycidoxypropyltriethoxysilane, β-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, etc. Or a mixture of two or more of the above. The addition amount of these silane coupling agents is usually 0.0
1 to 5 parts by weight is sufficient.

The anisotropic conductive film of the present invention may further contain an epoxy group-containing compound as an adhesion promoter. Examples of the epoxy group-containing compound include triglycidyl tris (2-hydroxyethyl) isocyanurate,
Neopentyl glycol diglycidyl ether, 1,6
-Hexanediol diglycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, phenol (EO)
₅ glycidyl ether, pt-butylphenyl glycidyl ether, diglycidyl adipic ester, diglycidyl phthalate, glycidyl methacrylate, butyl glycidyl ether and the like. Also,
The same effect can be obtained by alloying a polymer containing an epoxy group. These epoxy group-containing compounds are used as one kind or a mixture of two or more kinds, and the addition amount is usually 0.1 to 20 parts by weight based on 100 parts by weight of the polymer.

In order to improve and adjust the physical properties (mechanical strength, adhesiveness, optical properties, heat resistance, moisture resistance, weather resistance, crosslinking speed, etc.) of the anisotropic conductive film of the present invention, And a compound having an acryloxy group, a methacryloxy group or an allyl group.

As the compound used for this purpose, acrylic acid or methacrylic acid derivatives such as esters and amides thereof are the most common, and the ester residues include alkyl such as methyl, ethyl, dodecyl, stearyl and lauryl. In addition to the groups, cyclohexyl, tetrahydrofurfuryl, aminoethyl, 2-hydroxyethyl, 3-hydroxypropyl, 3-chloro-2-
And a hydroxypropyl group. Further, esters with polyfunctional alcohols such as ethylene glycol, triethylene glycol, polypropylene glycol, polyethylene glycol, trimethylolpropane, and pentaerythritol are also used. As the amide, diacetone acrylamide is typical. Examples of the polyfunctional crosslinking assistant include acrylic acid or methacrylic acid ester such as trimethylolpropane, pentaerythritol and glycerin, and compounds having an allyl group include triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, and diallyl isophthalate. , Diallyl maleate and the like. These compounds are used as one kind or a mixture of two or more kinds in an amount of usually 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, based on 100 parts by weight of the polymer. If the amount is more than 50 parts by weight, workability and film formability during preparation of the adhesive may be reduced.

In the anisotropic conductive film of the present invention, a hydrocarbon resin can be added to the adhesive for the purpose of improving workability, bonding and the like. In this case, the hydrocarbon resin to be added may be either a natural resin type or a synthetic resin type. Rosin, rosin derivatives, and terpene resins are preferably used in the natural resin system. In rosin, gum resin,
Tall oil-based resins and wood-based resins can be used.
As the rosin derivative, rosin obtained by hydrogenation, heterogeneization, polymerization, esterification, and metal salification can be used. As the terpene-based resin, terpene-based resins such as α-pinene and β-pinene, as well as terpene phenol resins can be used. Further, dammar, koval, and shellac may be used as other natural resins. On the other hand, in the case of synthetic resins, petroleum resins, phenol resins, and xylene resins are preferably used. Petroleum resins include aliphatic petroleum resins, aromatic petroleum resins, alicyclic petroleum resins, copolymerized petroleum resins, hydrogenated petroleum resins, pure monomer petroleum resins,
Coumarone indene resin can be used. As the phenolic resin, an alkylphenol resin and a modified phenol resin can be used. As the xylene-based resin, a xylene resin or a modified xylene resin can be used.

The amount of the hydrocarbon resin to be added is appropriately selected, but is preferably from 1 to 200 parts by weight, more preferably from 5 to 150 parts by weight, based on 100 parts by weight of the polymer.

In addition to the above additives, an antioxidant, an ultraviolet absorber, a dye, a processing aid and the like may be used in the present invention as long as the object of the present invention is not hindered.

In order to obtain the anisotropic conductive film of the present invention, the above-mentioned crosslinking agent (organic peroxide and / or photosensitizer) which generates a radical by heat or light and, if necessary, a crosslinking aid An agent, a silane coupling agent, and an epoxy group-containing compound are added to the polymer as a main component, and further, conductive particles and an acrylic monomer containing no epoxy group are blended.

The anisotropic conductive film of the present invention is prepared by uniformly mixing the above-mentioned polymer with the above-mentioned additives, conductive particles and an acrylic monomer containing no epoxy group, kneading them with an extruder, a roll or the like, and then calendering the mixture. A film can be formed in a predetermined shape by a film forming method such as roll, T-die extrusion, and inflation. At the time of film formation, embossing may be performed for the purpose of preventing blocking, facilitating pressure bonding with an adherend, and the like.

Further, each component is converted into a member (separator)
Can be uniformly dissolved in a solvent that has no effect on the surface, uniformly applied to the surface of the member (separator), and temporarily adhered to another adherend (polyimide, copper foil, etc.), and then cured by heat or light. it can.

The curing conditions for the anisotropic conductive film of the present invention depend on the type of organic peroxide used in the case of thermal curing, but are usually 70 to 170 ° C., preferably 7 to 170 ° C.
0 to 150 ° C., usually for 10 seconds to 120 minutes, preferably 2
0 seconds to 60 minutes.

In the case of photocuring using a photosensitizer,
Many light sources that emit light in the ultraviolet to visible range can be adopted as the light source, for example, ultra-high pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, mercury halogen lamp, carbon arc lamp, incandescent lamp, laser light, etc. Can be The irradiation time cannot be determined unconditionally depending on the type of lamp and the intensity of the light source, but is about several tens of seconds to several tens of minutes.

Further, in order to accelerate the curing, the laminate is preliminarily 4
It may be heated to 0 to 120 ° C. and irradiated with ultraviolet rays.

In this case, conductivity is generated in the pressing direction (film thickness direction) by the pressing at the time of the above-mentioned bonding, and this pressing force is appropriately selected and is usually 5 to 50 kg / cm ² , particularly 10 to
It is preferable to set the pressure to 30 kg / cm ² .

The anisotropic conductive film of the present invention has a conductivity of 10 Ω or less, particularly 5 Ω or less in the film thickness direction, and has a surface resistance of 10 ⁶ Ω or more, particularly 10 ⁹ Ω or more. Is preferred.

Further, the anisotropic conductive film of the present invention is made of, for example, an FPC or TAB and an IT on a glass substrate of a liquid crystal panel.
Used for the same applications as conventional anisotropic conductive films, such as used for connection between various terminals, such as connection with O-terminals. A crosslinked structure is formed during curing, and high adhesiveness, especially with metal Excellent adhesiveness, and excellent durability and heat resistance.

[0042]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

EXAMPLE 1 A 15% by weight solution of an ethylene-vinyl acetate copolymer (Ultracene 710 manufactured by Tosoh Corporation, vinyl acetate content: 28% by weight) was prepared and 100% by weight of an ethylene-vinyl acetate copolymer was prepared. 1 part by weight of trimethylolpropane triacrylate,
0.5 parts by weight of 1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 2.0 parts by weight of glycidyl methacrylate, and 0.5 parts by weight of γ-methacryloxypropyltrimethoxysilane And mixed well. Furthermore, 4% by volume of spherical copper particles (3.8 μm in particle diameter) manufactured by Fukuda Metal Foil Kogyo Kogyo is mixed with the ethylene-vinyl acetate copolymer, and the mixture is applied to the separator polyethylene terephthalate using a bar coater. And 5m wide
m, and a film having a thickness of 15 μm was obtained.

Example 2 A 15% by weight solution of an ethylene-vinyl acetate copolymer (Ultracene 750 manufactured by Tosoh Corporation, vinyl acetate content: 32% by weight) was prepared, and 100% by weight of an ethylene-vinyl acetate copolymer was prepared. Parts by weight, 4 parts by weight of dipentaerythritol hexaacrylate, 4.0 parts by weight of benzoyl peroxide, 4.0 parts by weight of glycidyl methacrylate, and 0.5 parts by weight of γ-methacryloxypropyltrimethoxysilane were added. And mixed well. Furthermore, 4% by volume of spherical copper particles (particle size: 7.6 μm) manufactured by Fukuda Metal Foil Kogyo Kogyo is mixed with the ethylene-vinyl acetate copolymer, and the mixture is applied to the separator, polyethylene terephthalate, using a bar coater. And 5m wide
m, and a film having a thickness of 15 μm was obtained.

Comparative Example 1 Toluene 1 as an epoxy resin
A 5% by weight solution was prepared, and 4% by volume of a spherical copper particle (3.8 μm in particle diameter) manufactured by Fukuda Metal Foil & Powder Co., Ltd. was mixed with the epoxy resin, and the mixture was mixed with a bar coater to obtain a polyethylene terephthalate as a separator. It was applied on top to obtain a film having a width of 5 mm and a thickness of 15 μm.

Comparative Example 2 A 15% by weight solution of phenolic resin in toluene was prepared, and spherical nickel particles (particle size: 7.6 μm) manufactured by Fukuda Metal Foil Powder Co., Ltd. were mixed at 4% by volume with respect to the phenolic resin. This was applied by a bar coater onto polyethylene terephthalate as a separator to obtain a film having a width of 5 mm and a thickness of 15 μm.

The above-mentioned sample was used for bonding the flexible printed circuit board and the transparent electrode glass to each other. The separator was peeled off, positioned by a monitor, and heated and pressed under a curing condition of 150 ° C. × 20 seconds. The conduction resistance to glass and the insulation resistance in the lateral direction were measured. The curing condition of Comparative Example 1 was 160 ° C. × 30 seconds, and the curing condition of Comparative Example 2 was 200 ° C. × 20 seconds. The results are shown below. Example 1 Characteristics immediately after adhesion Conduction resistance: 0.5Ω or less Insulation resistance: 10 ⁹ Ω or more Adhesive strength: 3.1 kg / inch Temporal change measurement (after 80 ° C./500 hours) Conduction resistance: 1.0Ω or less Insulation resistance: 10 ⁹ Ω or more Adhesive force: 3.1 kg / inch Example 2 Characteristics immediately after adhesion Conductive resistance: 0.5 Ω or less Insulation resistance: 10 ⁹ Ω or more Adhesive force: 2.8 kg / inch Temporal change measurement (after 80 ° C./500 hours) Conduction resistance: 0.8 Ω or less Insulation resistance: 10 ⁹ Ω or more Adhesion force: 2.8 kg / inch Comparative example 1 Characteristics immediately after adhesion Conduction resistance: 0.5 Ω or less Insulation resistance: 10 ⁹ Ω or more Adhesion force: 0.2 kg / inch aging measured (80 ° C. / 500 hours later) the conduction resistance: 250 [Omega] or higher insulation resistance: 10 ⁹ Omega more adhesion: 0.1 kg / inch Comparative example 2 adhesive immediately characteristic conduction resistance: 0.5 .OMEGA following insulation resistance: 10 ⁹ Omega On adhesion: 0.3 kg / inch temporal change measurement (80 ° C. / 500 hours later) the conduction resistance: 320Omu more insulation resistance: 10 ⁹ Omega more adhesion: 0.1 kg / inch

Examples 3 to 12 According to the method described in Example 1, films having a width of 5 mm and a thickness of 15 μm were obtained using the compositions shown in Tables 1 to 3 at the ratios shown in Tables 1 to 3. . Tables 1 to 3 show the results obtained by performing the same measurement as described above.

In the following table, the amount of each additive component is based on 100 parts by weight of the main component.

[0050]

[Table 1] * 1: Example 1 (Ultracene 710), Example 2 (Ultracene 750), Examples 3 and 4 (Ultracene 7)
60) * 2: 1,1-bis (t-butylperoxy) -3,
3,5-trimethylcyclohexane

[0051]

[Table 2] * 1: Bond First 2A, manufactured by Sumitomo Chemical Co., Ltd., vinyl acetate content: 8% by weight, glycidyl methacrylate content: 3% by weight * 2: Mitsubishi Chemical Corporation, MODIC E-100H, vinyl acetate content: about 20% by weight, Maleic anhydride content about 0.5% by weight * 3: LX 4110, manufactured by Sumitomo Chemical Co., Ltd., ethylene content 91% by weight, ethyl acrylate content 8% by weight,
Maleic anhydride content 1% by weight * 4: Ionomer resin of ethylene-methacrylic acid-sodium ion type, manufactured by Dupont Mitsui Polychemicals Co., Ltd., Himilan 1856, methacrylic acid content 5% by weight, ionization degree by sodium ion 40% * 5: 1,1-bis (t-butylperoxy) -3,
3,5-trimethylcyclohexane

[0052]

[Table 3] * 1: Bond First 2A, manufactured by Sumitomo Chemical Co., Ltd., vinyl acetate content: 8% by weight, glycidyl methacrylate content: 3% by weight * 2: Mitsubishi Chemical Corporation, MODIC E-100H, vinyl acetate content: about 20% by weight, Maleic anhydride content about 0.5% by weight * 3: LX 4110, manufactured by Sumitomo Chemical Co., Ltd., ethylene content 91% by weight, ethyl acrylate content 8% by weight,
Maleic anhydride content 1% by weight * 4: Ethylene-methacrylic acid-sodium ion type ionomer resin, manufactured by DuPont Mitsui Polychemicals, Himilan 1856, methacrylic acid content 5% by weight, ionization degree by sodium ion 40%

Incidentally, all the samples of Examples 1 to 12 could be wiped off with acetone and toluene very easily even after heat compression.

[0054]

The anisotropic conductive film of the present invention has a high adhesive strength, is cured in a short time at a low temperature, has good workability and transparency, and has a thickness even after being kept at a high temperature for a long time. Direction conductivity, surface direction insulation, and high adhesive strength.
It has excellent durability.

Claims (13)

[Claims] 1. An anisotropic conductive film in which conductive particles are dispersed in an adhesive and imparted with conductivity in the thickness direction by pressing in the thickness direction, wherein the adhesive is (A) )
Ethylene-vinyl acetate copolymer, (B) copolymer of ethylene and vinyl acetate with acrylate and / or methacrylate monomers, (C) copolymer of ethylene with vinyl acetate and maleic acid and / or maleic anhydride Coalescing,
(D) a copolymer of ethylene and an acrylate-based and / or methacrylate-based monomer with maleic acid and / or maleic anhydride; and (E) an ionomer in which the molecules of an ethylene-methacrylic acid copolymer are bonded with metal ions. An anisotropic conductive film characterized by being a heat or photo-curable adhesive obtained by adding a polymer selected from resins as a main component and further adding (F) an acrylic monomer. 2. The anisotropic conductive film, wherein the adhesive contains 0.1 to 10 parts by weight of an organic peroxide or a photosensitizer based on 100 parts by weight of a polymer. 3. The anisotropic conductive film according to claim 1, wherein the polymer is an ethylene-vinyl acetate copolymer, and the vinyl acetate content is 10 to 50% by weight. 4. The polymer is a copolymer of ethylene, vinyl acetate and acrylate and / or methacrylate monomers, the vinyl acetate content of which is 10 to 50% by weight, and the content of acrylate and / or methacrylate monomers. The anisotropic conductive film according to claim 1, wherein the ratio is 0.01 to 10% by weight. 5. The polymer is a copolymer of ethylene, vinyl acetate, maleic acid and / or maleic anhydride,
3. The anisotropic conductive film according to claim 1, wherein the vinyl acetate content is 10 to 50% by weight, and the maleic acid and / or maleic anhydride content is 0.01 to 10% by weight. . 6. The polymer according to claim 1, wherein the polymer is ethylene and an acrylate and / or methacrylate monomer and maleic acid and / or
Or a copolymer with maleic anhydride, whose acrylate and / or methacrylate monomer content is 10%.
The anisotropic conductive film according to claim 1 or 2, wherein the content of maleic acid and / or maleic anhydride is 0.01 to 10% by weight. 7. The polymer according to claim 1, wherein the polymer is an ionomer resin, the content of methacrylic acid is 1 to 30% by weight, and the degree of ionization by metal ions is 5 to 80%. Anisotropic conductive film. 8. The adhesive according to claim 1, wherein 0.01 to 5 parts by weight of a silane coupling agent and 0.1 to 20 parts by weight of an epoxy group-containing compound are added to 100 parts by weight of the polymer. The anisotropic conductive film according to claim 1. 9. The adhesive is prepared by adding 0.1 to 50 parts by weight of at least one selected from the group consisting of an acryloxy group-containing compound, a methacryloxy group-containing compound and an allyl group-containing compound to 100 parts by weight of a polymer. The anisotropic conductive film according to any one of claims 1 to 8, wherein 10. The anisotropic material according to claim 1, wherein the adhesive is obtained by adding 1 to 200 parts by weight of a hydrocarbon resin to 100 parts by weight of the polymer. Conductive film. 11. The anisotropic conductive film according to claim 1, wherein the conductive particles are contained in an amount of 0.1 to 15% by volume based on the polymer. 12. The conductive particles having a particle size of 0.1 to 10
The anisotropic conductive film according to claim 1, wherein the thickness is 0 μm. 13. The anisotropic conductive material according to claim 1, wherein the acrylic monomer is added in an amount of 0.1 to 60 parts by weight based on 100 parts by weight of the polymer. the film.