JP2002201440A - Anisotropic conductive resin film-like formed material, method for connecting circuit board using the same, and connection structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anisotropic conductive resin film-like formed material having excellent low-temperature rapid-curing properties and excellent pot life under high humidity conditions, a method for connecting a circuit board using the same, and a connecting structure. provide. SOLUTION: In a resin film-like product obtained by uniformly dispersing conductive particles, at least (1) conductive particles having no surface exposed to transition metals other than Ag, Au, and Pt; (2) radical polymerizable substance; (3)
An anisotropic conductive resin film formed product comprising a curing agent component that generates free radicals upon heating or light. A circuit board in which the anisotropic conductive resin film-like formation is interposed between substrates having circuit electrodes facing each other and pressurizes the substrate having circuit electrodes facing each other to electrically connect the electrodes in the pressing direction. Connection method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anisotropic conductive resin film-like product, a method for connecting circuit boards using the same, and a connection structure.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display and a TCP or F
An anisotropic conductive adhesive in which conductive particles are dispersed in an adhesive is used for the connection between the PC and the TCP and the connection between the FPC and the printed wiring board. In recent years, even when a semiconductor silicon chip is mounted on a substrate, so-called flip chip mounting, in which the semiconductor silicon chip is directly mounted on the substrate face down instead of conventional wire bonding, has been performed. Application of a water-soluble adhesive has been started (JP-A-59-120436, JP-A-60-1).
91228, JP-A-1-251787, JP-A-7-
No. 90237). In recent years, in the field of precision electronic equipment, the density of circuits has been increasing, and the electrode width and the electrode interval have become extremely narrow. For this reason, under the conventional connection condition of the circuit connection material using the epoxy resin system, there has been a problem that the wiring is dropped, peeled off or displaced. In addition, it is required to shorten the connection time to 10 seconds or less in order to improve production efficiency, and low-temperature rapid curing is indispensable. For this reason, Japanese Unexamined Patent Publication No. 10-273626 discloses a circuit connecting material using a radical polymerizable substance.

[0003]

However, when an anisotropic conductive film containing a radically polymerizable resin such as (meth) acrylate and an acidic substance such as phosphate ester is left under high humidity conditions, the initial connection resistance increases. There is a problem. An object of the present invention is to provide an anisotropically conductive resin film-like formed product having excellent low-temperature and fast-curing properties and excellent pot life under high humidity conditions, and a method for connecting a circuit board and a connection structure using the same. It is in.

[0004]

The present invention relates to a resin film-like product obtained by uniformly dispersing conductive particles, wherein the resin film-like product comprises at least the following components. . (1) conductive particles having no surface exposed to transition metals other than Ag, Au, and Pt; (2) radically polymerizable substance; (3)
A curing agent that generates free radicals by heating or light. Further, the present invention is an anisotropic conductive resin film-like formed product comprising at least the following components in a resin film-formed product obtained by uniformly dispersing conductive particles. (1) conductive particles having no surface exposed to transition metals other than Ag, Au, and Pt; (2) radically polymerizable substance; (3)
A curing agent that generates free radicals by heating or light and (4) a phosphoric ester. Further, in the present invention, the above-described anisotropic conductive resin film-like product is interposed between substrates having opposing circuit electrodes, the substrate having opposing circuit electrodes is pressurized, and if necessary, light ( Active energy)
Is a method for connecting circuit boards for electrically connecting electrodes in the pressing direction by irradiating the electrodes. Further, the present invention, the anisotropic conductive resin film-like formation is interposed between the substrates having opposing circuit electrodes, and pressurizes the substrate having the opposing circuit electrodes so that the gap between the electrodes in the pressing direction is increased. It is a connection structure electrically connected. The anisotropic conductive resin film-like formed product of the present invention,
Even when left at room temperature and high humidity, initial connection, moisture resistance test,
Even after various reliability tests such as cooling and heating cycles, an increase in connection resistance and a decrease in adhesive strength are suppressed, and excellent connection reliability is exhibited.
The anisotropic conductive resin film-shaped product is an anisotropic conductive resin formed on the surface of a film or an adherend.

According to the present invention, Cu, A
Conductive particles that are not exposed to transition metals such as Ni other than g and Au are used. In order to obtain sufficient moisture-resistant pot life and connection reliability, the outermost metal is Au, Ag, or a platinum group noble metal, and Au is more preferable. The conductive particles include metal particles such as Au, Ag, Ni, Cu, and solder, and carbon. When the surface layer exhibits the surface of a transition metal such as Ni or Co, Au, Ag, or a platinum group noble metal is used. The coated conductive particles. Au is more preferable as the coating material. In addition, non-conductive glass, ceramics, plastics and the like are coated with a conductive material, and the outermost layer is Cu,
It may be coated with a noble metal such as Ag or Au. Alternatively, conductive particles obtained by directly coating non-conductive glass, ceramic, plastic, or the like with Au, Ag, or a platinum group noble metal can be used. When plastic is used as the core or hot-melted metal particles such as solder are used as the core, it has deformability due to heating and pressing, so the contact area with the electrode increases at the time of connection and the variation in electrode height is absorbed and reliability is improved. It is preferable because the property is improved. The thickness of the noble metal coating layer is preferably 100 ° or more in order to obtain good resistance. However, Ni
In the case of providing a layer of a noble metal on a transition metal such as a transition metal such as Ni is exposed on the surface due to a defect of the noble metal layer or a defect of the noble metal layer generated when the conductive particles are mixed and dispersed,
In order to promote the polymerization of the radical polymerizable substance, the temperature is preferably 500 ° or more. The conductive particles are properly used in a range of 0.1 to 30% by volume based on 100 volumes of the adhesive component. In order to prevent a short circuit in an adjacent circuit due to excessive conductive particles, the content is more preferably 0.1 to 10% by volume.

The radically polymerizable substance used in the present invention is a substance having a functional group that is polymerized by a radical, and includes (meth) acrylate resin, maleimide resin, citraconic imide resin, nadiimide resin and the like. The radically polymerizable substance can be used in any state of a monomer and an oligomer, and the monomer and the oligomer can be used in combination.

[0007] (Meth) acrylate resins include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, and ethylene glycol di (meth) acrylate.
Acrylate, diethylene glycol (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydroxy-1,3-diacryloxypropane, 2,2-bis [4-((meth ) Acryloxymethoxy) phenyl] propane, 2,2-bis [4-((meth)
[Acryloxyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylate tricyclodecanyl (meth) acrylate, tris ((meth) acryloxyethyl) isocyanurate, urethane (meth) acrylate, etc., alone or in combination of two types A mixture of the above may be used. If necessary, a radical polymerization inhibitor such as hydroquinone or methyl ether hydroquinone may be used within a range where the curing properties are not impaired.

The maleimide resin contains at least two maleimide groups in the molecule.
1-methyl-2,4-bismaleimidobenzene, N,
N'-m-phenylenebismaleimide, N, N'-p-
Phenylenebismaleimide, N, N'-m-toluylenebismaleimide, N, N'-4,4-biphenylenebismaleimide, N, N'-4,4- (3,3'-dimethylbiphenylene) bismaleimide, N, N'-4,4-
(3,3′-dimethyldiphenylmethane) bismaleimide, N, N′-4,4- (3,3′-diethyldiphenylmethane) bismaleimide, N, N′-4,4-diphenylmethanebismaleimide, N, N ′ -4,4-diphenylpropanebismaleimide, N, N'-4,4-diphenyletherbismaleimide, N, N'-3,3'-
Diphenylsulfone bismaleimide, 2,2-bis (4
-(4-maleimidophenoxy) phenyl) propane,
2,2-bis (3-s-butyl-3,4- (4-maleimidophenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidophenoxy) phenyl) decane, 4,4′-cyclohexyl Silidene-bis (1- (4-maleimidophenoxy) -2-cyclohexylbenzene,
2,2-bis (4- (4-maleimidophenoxy) phenyl) hexafluoropropane, and the like, and these may be used alone or as a mixture of two or more.

The citraconic imide resin is obtained by polymerizing a citraconic imide compound having at least one citraconic imide group in a molecule. Examples of the citraconic imide compound include phenylcitraconic imide and 1-methyl-2. , 4-biscitraconimidobenzene, N'N-m-phenylenebiscitraconimide,
N'N-p-phenylenebiscitraconimide, N'N
-4,4-biphenylenebiscitraconimide, N ',
N-4,4- (3,3-dimethylbiphenylene) biscitraconimide, N ', N-4,4- (3,3-dimethylphenylmethane) biscitraconimide, N', N-
4,4- (3,3-diethyldiphenylmethane) biscitraconimide, N ', N-4,4-diphenylmethanebiscitraconimide, N', N-4,4-diphenylpropanebiscitraconimide, N ', N- 4,4-diphenyl ether biscitraconimide, N ', N-
4,4-diphenylsulfonebiscitraconimide,
2,2-bis (4- (4-citraconimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-citraconimidophenoxy) phenyl) propane, 1,1- Bis (4- (4-citraconimidophenoxy) phenyl) decane, 4,4′-cyclohexylidene-bis (1- (4-citraconimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4 -(4-citraconimidophenoxy) phenyl) hexafluoropropane and the like, and they may be used alone or as a mixture of two or more.

The nadimide resin is a polymer obtained by polymerizing a nadimide compound having at least one nadimide group in a molecule.
Phenylnadiimide, 1-methyl-2,4-bisnadiimidebenzene, N ′, Nm-phenylenebisnadiimide, N ′, Np-phenylenebisnadiimide, N ′,
N-4,4-bisphenylenebisnadimide, N ', N
-4,4- (3,3-dimethylbiphenylene) bisnadiimide, N ', N-4,4- (3,3-dimethyldiphenylmethane) bisnadiimide, N', N-4,4-
(3,3-diethyldiphenylmethane) bisnadiimide, N ', N-4,4-diphenylmethanebisnadiimide, N', N-4,4-diphenyletherbisnadiimide, N ', N-4,4-diphenylsulfonebisnadiimide, 2,2-bis-4- (4-nadiimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-nadiimidophenoxy) phenyl)
Decane, 4,4'-cyclohexylidene-bis (1-
(4-nadiimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4- (4-nadiimidophenoxy) phenyl) hexafluoropropane, and the like, alone or as a mixture of two or more kinds You may.

When the above radical polymerizable substance is used, a polymerization initiator is used as a curing agent that generates free radicals by heating or light. The polymerization initiator is not particularly limited as long as it is a compound that generates free radicals by heating or light, and includes a peroxide compound, an azo compound, and the like, and is appropriately determined depending on the intended connection temperature, connection time, pot life, and the like. From the viewpoint of high reactivity and pot life, an organic peroxide having a half-life of 10 hours at a temperature of 40 ° C. or higher and a half-life of 1 minute at a temperature of 180 ° C. or lower is preferable. Temperature of 50 ° C or higher and half-life of 1
Organic peroxides having a temperature of 170 ° C. or less are preferred. In this case, the compounding amount is about 0.05 to 20% by weight,
0.1 to 5% by weight is more preferred. Specifically, it can be selected from diacyl peroxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, hydroperoxide, silyl peroxide and the like. Specifically, it is selected from peroxyesters, dialkyl peroxides, hydroperoxides, and silyl peroxides, and is more preferably selected from peroxyesters having high reactivity. These can be used by mixing as appropriate.

The diacyl peroxides include isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic Peroxide, benzoylperoxytoluene, benzoyl peroxide and the like.

The peroxydicarbonates include di-n-propylperoxydicarbonate, diisopropylperoxydicarbonate, bis (2-t-butylcyclohexyl) peroxydicarbonate and di-2-carbonate.
Ethoxymethoxyperoxydicarbonate, di (2-
Ethylhexylperoxy) dicarbonate, dimethoxybutylperoxydicarbonate, di (3-methyl-
3-methoxybutylperoxy) dicarbonate.

The peroxyesters include cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxynodecanoate. , T-hexylperoxy neodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanate, 2,
5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanonate, t-hexylperoxy-2-ethylhexanonate , T-butylperoxy-2-ethylhexanonate, t-butylperoxyisobutyrate, 1,1-bis (t-butylperoxy) cyclohexane, t-hexylperoxyisopropylmonocarbonate, t-butylperoxy Oxy-3,5,5-trimethylhexanonate, t-butylperoxylaurate, 2,5-dimethyl-2,5-
Di (m-toluoylperoxy) hexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t
-Hexylperoxybenzoate, t-butylperoxyacetate and the like.

The peroxyketals include 1,1-
Bis (t-hexylperoxy) -3,3-5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5 -Trimethylcyclohexane,
1,1- (t-butylperoxy) cyclododecane,
2,2-bis (t-butylperoxy) decane and the like.

The dialkyl peroxides include:
α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t
-Butyl cumyl peroxide and the like.

The hydroperoxides include diisopropylbenzene hydroperoxide, cumene hydroperoxide and the like.

Examples of silyl peroxides include t-butyltrimethylsilyl peroxide, bis (t-butyl) dimethylsilyl peroxide, t-butyltrivinylsilyl peroxide, bis (t-butyl) divinylsilyl peroxide, tris ( (t-butyl) vinylsilyl peroxide, t-butyltriallylsilyl peroxide, bis (t-butyl) diallylsilyl peroxide, tris (t-butyl) allylsilyl peroxide and the like.

Further, in order to suppress the corrosion of the connection terminals of the circuit member, chlorine ions and organic acids contained in the curing agent should not be used.
It is preferably at most 000 ppm, and more preferably an organic acid which is less generated after thermal decomposition.
In addition, since the stability of the manufactured circuit member is improved, it is preferable that the circuit member has a weight retention of 20% by weight or more after being left open at room temperature (25 ° C.) and normal pressure for 24 hours. These curing agents can be used alone or as a mixture, and a decomposition accelerator, an inhibitor and the like may be used as a mixture. A microcapsule obtained by coating these curing agents with a polyurethane-based or polyester-based polymer substance or the like is preferable because the pot life can be further extended.

Further, by blending a phosphoric ester, the adhesive strength to an inorganic substance such as a metal can be improved. In particular, when a radical polymerizable substance having a phosphate ester structure is used, the adhesive strength to inorganic substances such as metals can be further improved. The amount of the radical polymerizable substance having a phosphate ester structure is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight. The radical polymerizable substance having a phosphate ester structure is obtained as a reaction product between phosphoric anhydride and 2-hydroxyethyl (meth) acrylate. Specifically, mono (2-methacryloyloxyethyl) acid phosphate, di (2-
(Methacryloyloxyethyl) acid phosphate and the like. These can be used alone or in combination.

The anisotropic conductive resin film of the present invention is formed of polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin in order to impart film formability, adhesiveness, and stress relaxation during curing.
Polymer components such as a polyimide resin, a xylene resin, a phenoxy resin, a polyurethane resin, and a urea resin can also be used. These polymer components have a molecular weight of 10,000 to
Those of 10000000 are preferred. Further, these resins may be modified with a radical polymerizable functional group, and in this case, heat resistance is improved. The compounding amount of the polymer component is 2 to 80% by weight, preferably 5 to 70% by weight, and particularly preferably 10 to 60% by weight. If it is less than 2% by weight, stress relaxation and adhesive strength are not sufficient, and if it exceeds 80% by weight, fluidity decreases.

The anisotropic conductive resin film-form of the present invention may optionally contain a filler, a softener, an accelerator, an antioxidant, a coloring agent, a flame retardant, and a coupling agent. It is preferable to include a filler, because an improvement in connection reliability and the like can be obtained. It can be used as long as the maximum diameter of the filler is smaller than the particle diameter of the conductive particles, and the range of 5 to 60% by volume is preferable. If it exceeds 60% by volume, the effect of improving reliability is saturated. As the coupling agent, a vinyl group, an acrylic group, an amino group, an epoxy group, an azide group and an isocyanate group-containing material are preferable from the viewpoint of improving the adhesiveness.

The substrate having a circuit electrode to be bonded using the anisotropic conductive resin film-form formed product of the present invention is not particularly limited as long as it has an electrode required for electrical connection. However, chip components such as semiconductor chips, resistor chips, and capacitor chips, circuit boards such as printed boards and flexible printed boards, image display boards such as LCD panels, PDP panels, and EL panels, tape carrier packages, and circuit components such as COF Are used in combination as needed. The conditions for connection are not particularly limited, but a connection temperature of 90 to 250 ° C. and a connection time of 1
The time is from 10 seconds to 10 minutes, which is appropriately selected depending on the intended use, adhesive, and substrate, and post-curing may be performed as necessary.
The connection is performed by heating and pressurizing, but energy other than heat, for example, light, ultrasonic waves, electromagnetic waves, or the like may be used as necessary. Further, the anisotropic conductive resin film-like formed product of the present configuration may be used by dividing into two or more layers.

[0024]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the scope of the present invention is not limited to these Examples. (Example 1) Phenoxy resin (manufactured by Union Carbide Co., Ltd., trade name: PKHC, average molecular weight: 45,000) 5
0 g of MEK (methyl ethyl ketone, boiling point 79.6)
C) to give a solution having a solid content of 50% by weight. As the radical polymerizable substance, isocyanuric acid ethylene oxide-modified diacrylate (manufactured by Toagosei Co., Ltd., trade name: M-215) and phosphate ester type acrylate (manufactured by Kyoeisha Yushi Co., Ltd., trade name: P-2M) were used. As a curing agent that generates free radicals by heating or light,
A 50% by weight hydrocarbon solution of 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane (trade name Perhexa 250, manufactured by NOF CORPORATION) was used. A 0.09 thickness is applied to the surface of a particle (compression elastic modulus 480 kg / mm ² ) having polystyrene as a core as the conductive particle.
Conductive particles having an average particle diameter of 5 μm provided with an Ag layer of μm were used. 50 g of phenoxy resin, 50 g of isocyanuric acid ethylene oxide-modified diacrylate at a solid weight ratio,
Phosphate ester type acrylate 2g, 2,5-dimethyl-2,5-bis (2-ethylhexanoyl peroxy)
5 g of hexane was blended, and 3 more conductive particles were added.
Volume% was dispersed and applied to a PET (polyethylene terephthalate) film with a thickness of 80 μm and a surface treated on one side using a coating device, and dried with hot air at 70 ° C. for 10 minutes to form an anisotropic adhesive layer having a thickness of 35 μm. A conductive resin film-like product was obtained.

Example 2 Polystyrene was used as the conductive particles.
Particles (compression elastic modulus 366 kg / mm) ^Two)of
Average particle size provided with a 0.1 μm thick Ag layer on the surface
6. Use a 15 μm-thick one in the same manner as in Example 1.
An electrically conductive resin film-like product was obtained.

Example 3 Polystyrene was used as the conductive particles.
Particles having a compression modulus of 480 kg / mm ^Two)of
An Ag layer having a thickness of 0.1 μm is provided on the surface.
Average particle size with 0.04 μm thick Au layer on the outside
Use an anisotropic conductive material of 5 μm in the same manner as in Example 1.
A resinous film-like formed product was obtained.

Example 4 Polystyrene was used as the conductive particles.
Particles having a compression modulus of 480 kg / mm ^Two)of
A 0.1 μm thick Ni layer is provided on the surface, and the Ni layer
Average particle size with a 0.05 μm thick Au layer on the outside
Use an anisotropic conductive material of 5 μm in the same manner as in Example 1.
A resinous film-like formed product was obtained.

Comparative Example 1 Polystyrene was used as the conductive particles.
Particles having a compression modulus of 480 kg / mm ^Two)of
Average particle size 5 with a 0.2 μm thick Ni layer on the surface
μm, and anisotropically conductive as in Example 1.
A resin film-like product was obtained.

Comparative Example 2 Polystyrene was used as the conductive particles.
Particles having a compression modulus of 480 kg / mm ^Two)of
A nickel layer having a thickness of 0.2 μm is provided on the surface.
Average grain size provided with a 0.04 μm thick Au layer outside the layer
Use an element with a diameter of 5 μm and anisotropically as in Example 1.
A conductive resin film-like product was obtained.

(Circuit connection) A line width of 30 μm and a pitch of 30
A tape carrier package (TCP) having 150 μm, 18 μm thick copper circuits and ITO glass (manufactured by Geomatic Co., Ltd., surface resistance 20-30 Ω / □, thickness 1.
1 mm was heated and pressed at 140 ° C. and 3 MPa for 15 seconds, and connected over a width of 2 mm to obtain a connection structure. At this time, after bonding the adhesive surface of the anisotropic conductive resin film-shaped product on the ITO glass in advance, the connection is made temporarily by heating and pressing at 80 ° C. and 0.5 MPa for 3 seconds, and then the PET film is peeled off. And connected with TCP.

(Measurement of connection resistance) The prepared anisotropic conductive resin film was stored at -20 ° C and at 85 ° C at 85 ° C.
% RH in a constant-temperature and constant-humidity chamber for 100 hours, and then connected to the circuit described above.
The initial resistance between adjacent circuits of P was measured with a multimeter. The resistance value is shown as an average of 150 resistances between adjacent circuits. Table 1 shows the measurement results.

[0032]

[Table 1]

The connection structure obtained in Example 1 is -20
Each of the samples stored at 30 ° C. or stored in a thermo-hygrostat at 30 ° C. and 85% RH showed good initial connection reliability of 2.5Ω or less. Similarly, the connection structures of Examples 2 and 3 were stored at −20 ° C. or at 30 ° C. and 85% RH.
In any of the samples stored in the constant temperature and humidity chamber, good connection reliability of 2.5Ω or less was obtained. In contrast, in Comparative Examples 1 and 2, good initial connection reliability was obtained for the connection structure stored at −20 ° C., but at 30 ° C. and 85% R.
The sample stored in the constant temperature and humidity chamber of H had a large initial connection resistance of 10Ω or more.

(Measurement of Adhesive Strength) In Examples 1 to 3,
All of those stored in a thermo-hygrostat at 20 ° C. or 30 ° C. and 85% RH showed good adhesion strength of about 1000 N / m. On the other hand, in Comparative Examples 1 and 2, the adhesive strength was -20 ° C. or 30 ° C., 85% RH.
All of those stored in a thermo-hygrostat of 1000 N /
m and good adhesive strength were obtained.

(Evaluation of Insulating Property) A printed circuit board having a comb-shaped circuit in which 250 copper circuits having a line width of 50 μm, a pitch of 100 μm, and a thickness of 18 μm are alternately arranged using the obtained anisotropic conductive resin film-like product. And line width 50μ
m, pitch 100μm, thickness 18μm copper circuit 500
140 tape carrier packages (TCP)
It was heated and pressed at 15 ° C. and 3 MPa for 15 seconds and connected over a width of 2 mm. A voltage of 100 V was applied to the comb-shaped circuit of the connection body, and the insulation resistance value after a high-temperature and high-humidity test at 85 ° C. and 85% RH for 500 hours was measured. In each case, good insulation of 10 ⁹ Ω or more was obtained, and no decrease in insulation was observed.

(Evaluation of fluidity) Thickness 35 μm, 5 mm ×
A 5 mm anisotropic conductive resin film-shaped product was sandwiched between 0.7 mm thick, 15 mm × 15 mm glass, and heated and pressed at 140 ° C. and 3 MPa for 15 seconds.
When the value of fluidity (B) / (A) was determined using the initial area (A) and the area (B) after heating and pressing, Examples 1 to 3 were obtained.
Was in the range of 1.9 to 2.0. On the other hand, Comparative Examples 1 and 2 were 1.8 and 1.9, respectively.

(Elastic Modulus After Curing) The elastic modulus at 40 ° C. after curing of the anisotropic conductive resin film-formed product of Example 1 was 1.5 GPa. From the above-mentioned adhesive strength, insulating properties, fluidity, and elastic modulus after curing, the values of the examples of the present invention and the values of the comparative examples show almost the same values, but as shown in Table 1, the initial resistance value Are very different. Since the adhesive strength, insulating property, fluidity, and the like show the same characteristics in Examples and Comparative Examples, the coating layer on the surface of the conductive particles seems to be extremely thin, but significantly affects the initial connection resistance. As in the present invention, in a conductive particle having no surface exposed to transition metals other than Ag, Au, and Pt, polymerization of a radical polymerizable substance is not promoted on the surface of the conductive particle, and the initial connection resistance is low. Shows good values. According to the fourth embodiment, even when a transition metal such as Ni is used, the outer surface is coated with Ag, Au, Pt, or the like at a temperature of 500 ° or more so that the inner transition metal is not exposed. Excellent storage stability even after temperature and humidity treatment, and initial connection resistance does not increase.

[0038]

According to the present invention, an anisotropic conductive resin film-like product having a long pot life even when left under high humidity conditions, and a circuit connection structure using the same are provided. can do.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01B 5/16 H01B 5/16 H01L 21/60 311 H01L 21/60 311R 311S H01R 11/01 501 H01R 11 / 01 501A (72) Inventor Masaki Yusa 48 Wadai, Tsukuba, Ibaraki Prefecture Within Hitachi Chemical Co., Ltd. Research Institute (72) Inventor Mitsugu Fujinawa 1150 Goshomiya, Odate, Shimodate City, Ibaraki Prefecture In-house F-term (reference) 4J004 AA10 AA11 AA18 AA19 AB05 AB06 BA02 FA05 4J040 DF041 DF051 EH021 HA026 HA066 KA03 KA11 KA16 KA32 LA05 LA09 NA20 PA23 PA30 PA32 PA33 5F044 LL09 NN19 5G301 DA01 H

Claims (4)

[Claims] 1. An anisotropic conductive resin film-form formed by uniformly dispersing conductive particles, comprising at least the following components. (1) conductive particles having no surface exposed to transition metals other than Ag, Au, and Pt; (2) radically polymerizable substances; and (3) curing agents that generate free radicals by heating or light. 2. An anisotropic conductive resin film-form formed by uniformly dispersing conductive particles, comprising at least the following components. (1) conductive particles whose surfaces are not exposed to transition metals other than Ag, Au, and Pt; (2) radical polymerizable substance; (3) a curing agent that generates free radicals by heating or light; and (4) phosphoric acid ester 3. An anisotropic conductive resin film-like product according to claim 1 or 2 is interposed between substrates having opposing circuit electrodes, and the substrate having opposing circuit electrodes is pressurized. A circuit board connection method for electrically connecting electrodes in the pressing direction. 4. An anisotropic conductive resin film-like product according to claim 1 or 2 is interposed between substrates having opposing circuit electrodes, and the substrate having opposing circuit electrodes is pressurized. A connection structure in which electrodes in the pressing direction are electrically connected.