JP2003064332A - Circuit-connecting adhesive and circuit-connected structural material by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit-connecting adhesive excellent in low temperature rapid curing property, and also having a good preserving property and stable connection resistance, and a circuit-connected structural material by using the same. SOLUTION: This circuit-connecting adhesive being positioned between substrates having opposing electrodes, and connecting the electrodes electrically by pressurizing the substrates having opposing electrodes in pressurizing direction contains a radically polymerizable material and at least electric conductive particles surface-treated with a compound having at least 1 epoxy group.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an adhesive for circuit connection and a circuit connection structure using the same.

[0002]

2. Description of the Related Art In recent years, various adhesive materials have been used in the fields of semiconductors and liquid crystal displays for fixing electronic components and for making circuit connections. In these applications, higher densities and higher definition are progressing, and adhesives are required to have high adhesive strength and reliability. In particular, as the circuit connecting material, liquid crystal display and TCP or FPC and TCP
An anisotropic conductive adhesive in which conductive particles are dispersed in an adhesive is used for the connection with the FPC and the connection between the FPC and the printed wiring board. In addition, recently, even when mounting a semiconductor silicon chip on a substrate, instead of the conventional wire bond,
So-called flip-chip mounting in which a semiconductor silicon chip is directly mounted face down on a substrate is performed, and application of an anisotropic conductive adhesive is also started here (JP-A-59-120436, JP-A-60). -191228
JP-A-1-251787, JP-A-7-90237.
Issue).

Further, in recent years, in the field of precision electronic equipment, the circuit density has been increasing, and the electrode width and the electrode interval have become extremely narrow. Therefore, under the conventional connection conditions of the circuit connecting adhesive using the epoxy resin, there is a problem that the wiring is dropped, peeled, or displaced. Further, in order to improve the production efficiency, there is a strong demand for shortening the connection time so that the connection can be made in 10 seconds or less, and low temperature fast curing property is indispensable. Therefore, JP-A-1
0-273636 discloses a circuit connecting material using a radically polymerizable substance.

[0004]

However, if the adhesive containing the radically polymerizable compound and the conductive particles is left in the air, there is a problem that the connection resistance when connecting is increased. An object of the present invention is to provide an adhesive for circuit connection, which has excellent low-temperature rapid curing property, good storage stability, and stable connection resistance, and a circuit connection structure using the same.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a substrate having circuit electrodes facing each other is interposed, and a substrate having circuit electrodes facing each other is pressed to electrically connect the electrodes in the pressing direction. An adhesive for circuit connection, wherein the adhesive contains conductive particles surface-treated with a radically polymerizable compound and a compound having at least one epoxy group, It is an adhesive for circuit connection containing a compound that generates a radical by light or heating, or a phosphoric acid ester compound. Another aspect of the present invention is that an adhesive for circuit connection is interposed between substrates having circuit electrodes facing each other and pressure is applied to the substrate having circuit electrodes facing each other to electrically connect the electrodes in the pressing direction. And the circuit connection adhesive is a circuit connection structure in which the circuit connection adhesive is an adhesive containing radically polymerizable substances and conductive particles surface-treated with a compound having at least one epoxy group.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The conductive particles used in the present invention are not particularly limited as long as they have conductivity capable of obtaining an electrical connection, but Au, Ag, Ni, Cu, Co, solder, etc. There are metal particles and carbon. Further, non-conductive glass, ceramics, plastic, etc. coated with a conductive material of the above metal can also be used. At this time, the thickness of the metal layer to be coated is 100 to obtain sufficient conductivity.
Å or more is preferable. When a layer of a noble metal is provided on a transition metal such as Co, Zn, Cu, or Ni, free radicals are generated by a redox action caused by a defect of the noble metal layer or a defect of the noble metal layer generated during mixed dispersion of conductive particles. Occurs and causes a decrease in pot life, so the conductive particles are surface-treated. The conductive particles are added to the adhesive component for circuit connection in an amount of 0.
Used in the range of 1 to 30% by volume, preferably 0.1 to 2
It can be used in the range of 0% by volume. As the compound for treating the surface of the conductive particles, a compound having at least one epoxy group is preferable. The compound having at least one epoxy group may be liquid or solid,
If it is a solid, dissolve it in an organic solvent or water before use. Further, it is preferable to use a liquid compound after dissolving it in an organic solvent or the like. The organic solvent is not particularly limited as long as it is not reactive with the compound having at least one epoxy group and can dissolve the compound having at least one epoxy group, but is not limited to methanol, ethanol, isopropar, methyl ethyl ketone, ethyl acetate, Toluene or the like is preferable in terms of drying the conductive particles after the surface treatment. The concentration of the compound having at least one epoxy group contained in the treatment liquid is preferably 0.05 to 20% by weight. If it is less than 0.05% by weight, the surface treatment is not effectively carried out, and if it exceeds 20% by weight, the amount of the compound having at least one epoxy group coated on the surface of the conductive particles is increased and the connection resistance is increased. Will end up. The treatment conditions such as temperature and time for treatment are not particularly limited, but the treatment temperature is generally room temperature (25 ° C) to 100 ° C, and the treatment time is 10
It is preferably in the range of seconds to 1 hour. The treated conductive particles are filtered and then dried before use. The drying conditions are appropriately selected depending on the organic solvent used, but may range from room temperature (25 ° C) to
Perform at 150 ° C.

At least one used in the present invention for surface treatment
Examples of the compound having one epoxy group include phenylglycidyl ether, glycidyl (meth) acrylate, γ-
Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4epoxycyclohexyl) ethyltri Methoxysilane, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin,
There are bisphenol F novolac type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type epoxy resin, aliphatic chain epoxy resin, and the like. May be halogenated or hydrogenated. Two or more of these epoxy compounds may be used in combination.

The radically polymerizable compound used in the present invention is a compound having a functional group which is polymerized by radicals,
There are (meth) acrylate resins, maleimide resins, citracone imide resins, nadiimide resins and the like, and two or more kinds may be mixed and used. The radical polymerizable compound can be used in any state of monomer and oligomer, and the monomer and oligomer may be mixed and used. The (meth) acrylate resin is obtained by radically polymerizing (meth) acrylate,
As (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate,
Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydroxy-1,3-diacryloxypropane, 2,2- Screw [4
-(Acryloxymethoxy) phenyl] propane, 2,
2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, tris (acryloxyethyl) isocyanurate, urethane (meth) acrylate, isocyanuric acid There are ethylene oxide-modified diacrylates and the like, which may be used alone or in combination of two or more kinds. Further, if necessary, a radical polymerization inhibitor such as hydroquinone or methyl ether hydroquinone may be used within a range that does not impair the curability.

Furthermore, when a phosphoric acid ester compound is used as the radically polymerizable compound, the adhesive force to an inorganic substance such as a metal can be improved. The amount of the phosphoric acid ester compound used is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight. The phosphoric acid ester compound is obtained as a reaction product of phosphoric anhydride and 2-hydroxyethyl (meth) acrylate. Specifically, mono (2-
Methacryloyloxyethyl) acid phosphate,
Examples thereof include di (2-methacryloyloxyethyl) acid phosphate, which may be used alone or in combination.

The maleimide resin has at least one maleimide group in the molecule, and examples thereof include phenylmaleimide, 1-methyl-2,4-bismaleimidebenzene, and N, N'-m-phenylenebis. Maleimide, N,
N'-p-phenylene bismaleimide, N, N'-4,4-biphenylene bismaleimide, 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-diphenylmethane bismaleimide, N, N'- 4,4-diphenylpropane bismaleimide, N, N'-4,4-diphenylether bismaleimide, N, N'-4,4-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′-cyclohexylidene-bis (1- (4-maleimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2 -Bis (4
There are-(4-maleimidophenoxy) phenyl) hexafluoropropane and the like, which may be used alone or in combination of two or more kinds.

The citraconimide resin is obtained by polymerizing a citraconimide compound having at least one citraconimide group in the molecule. Examples of the citraconimide compound include phenyl citraconimide and 1-methyl-2. , 4-biscitraconimide benzene, N, N'-m-phenylene biscitraconimide, N, N '
-P-phenylene bis citraconimide, N, N'-4,4
-Biphenylene biscitraconimide, N, N'-4,4-
(3,3-Dimethylbiphenylene) biscitraconimide, N, N'-4,4- (3,3-dimethyldiphenylmethane) biscitraconimide, N, N'-4,4- (3,3-
Diethyldiphenylmethane) biscitraconimide, N,
N'-4,4-diphenylmethanebiscitraconimide,
N, N'-4,4-diphenylpropanebiscitraconimide, N, N'-4,4-diphenyletherbiscitraconimide, 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, etc., You may use individually or in mixture of 2 or more types.

The nadimide resin is obtained by polymerizing a nadimide compound having at least one nadimide group in the molecule. Examples of the nadimide compound include:
Phenylnadiimide, 1-methyl-2,4-bisnadiimidebenzene, N, N'-m-phenylenebisnadiimide,
N, N'-p-phenylenebisnadiimide, N, N'-4,4-
Biphenylene bis nadiimide, 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-diphenylpropane bisnadimide, N, N'-4,4-diphenyl ether bisnadimide, N, N'-4,4-diphenylsulfone bisnadimide, 2,2-bis (4- (4-nadimide phenoxy) Phenyl) propane, 2,2-bis (3-s-
Butyl-3,4- (4-nadiimidophenoxy) phenyl) propane, 1,1-bis (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, which may be used alone or in combination of two or more. Is also good.

When the above radically polymerizable compound is used, a polymerization initiator is used. The polymerization initiator is not particularly limited as long as it is a compound that generates a radical by heat or light, and may be a peroxide, an azo compound, or the like, and may be appropriately selected in consideration of the desired connection temperature, connection time, storage stability, and the like. From the viewpoint of high reactivity and storage stability, 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 180 ° C. or lower is selected, and a half-life of 10 hours is preferred.
The temperature of time is 50 ° C or more and the temperature of 1 minute half-life is 1
An organic peroxide having a temperature of 70 ° C. or lower is particularly preferable. When the connection time is 10 seconds, the compounding amount of the polymerization initiator for obtaining a sufficient reaction rate is preferably 1 to 20% by weight, and particularly preferably 2 to 15% by weight. Specific compounds of the organic peroxide used in the present invention include diacyl peroxide,
It can be selected from peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, hydroperoxide, silylperoxide, etc., but peroxyester, dialkylperoxide, hydroperoxide, silylperoxide are among the initiators. The amount of chlorine ions and organic acid is less than 5000 ppm, the organic acid generated after thermal decomposition is small, and corrosion of the connection terminal of the circuit member can be suppressed, which is particularly preferable.

Examples of diacyl peroxides include isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide and succinic. Examples thereof include peroxide, benzoylperoxytoluene, and benzoylperoxide.

Examples of peroxydicarbonates include di-n-propylperoxydicarbonate, diisopropylperoxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate and di-2-ethoxymethoxyperoxydicarbonate. Carbonate, di (2-ethylhexylperoxy) dicarbonate, dimethoxybutylperoxydicarbonate, di (3-methyl-3)
-Methoxybutyl peroxy) dicarbonate and the like.

Peroxyesters include cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxynoedecanoate. , T-hexylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanonate, 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-hexylperoxyisopropyl monocarbonate, t-butyl Peroxy-3,5
5-trimethylhexanonate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di (m-toluoylperoxy) hexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy 2-Ethylhexyl monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxyacetate and the like can be mentioned.

Among the peroxyketals, 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.

In the dialkyl peroxides, α,
α'-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane, t-butylcumyl peroxide and the like can be mentioned.

Examples of hydroperoxides include diisopropylbenzene hydroperoxide and cumene hydroperoxide.

Examples of silyl peroxides include t-butyltrimethylsilyl peroxide and bis (t-butyl).
Dimethylsilyl peroxide, t-butyltrivinylsilyl peroxide, bis (t-butyl) divinylsilyl peroxide, tris (t-butyl) vinylsilyl peroxide, t-butyltriallylsilyl peroxide, bis (t-butyl) ) Diallyl silyl peroxide,
Examples thereof include tris (t-butyl) allylsilyl peroxide.

Further, in order to suppress the corrosion of the connection terminals of the circuit members, the chlorine ion and the organic acid contained in the curing agent should be 5%.
The amount is preferably 000 ppm or less, and more preferably the amount of organic acid generated after thermal decomposition is small.
In addition, since the stability of the produced circuit connecting material is improved, it will be 2
It is preferable to have a weight retention of 0% by weight or more. These can be appropriately mixed and used. These free radical generators can be used alone or as a mixture, and may be used as a mixture with a decomposition accelerator, an inhibitor and the like. Microcapsules obtained by coating these free radical generators with polyurethane-based or polyester-based polymer substances are preferable because the pot life is extended.

In addition to the radically polymerizable compound, an epoxy resin can be blended as a thermosetting resin. As the epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin, fat There are cyclic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type epoxy resin, aliphatic chain type epoxy resin and the like, and these epoxy resins are halogenated. Well, it may be hydrogenated. These epoxy resins are 2
You may use together 1 or more types.

Examples of the curing agent for the epoxy resin include amines, phenols, acid anhydrides, imidazoles, dicyandiamide and the like used as a curing agent for ordinary epoxy resins. Furthermore, tertiary amines and organic phosphorus compounds that are usually used as a curing accelerator may be used as appropriate. As a method of reacting the epoxy resin, cation polymerization may be performed using a sulfonium salt, an iodonium salt, or the like, instead of using the curing agent.

The circuit connecting adhesive of the present invention is provided with film forming properties, adhesive properties, and stress relaxation properties upon curing.
Polymer components such as polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin, polyimide resin, xylene resin, phenoxy resin, polyurethane resin and urea resin are used. These polymer components preferably have a molecular weight of 10,000 to 10,000,000. Further, these resins may be modified with a radically polymerizable functional group, in which case the heat resistance is improved. Furthermore, radically polymerizable functional groups and epoxy groups,
It may be modified with a carboxyl group or the like, in which case the heat resistance is improved. The blending 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 force are not sufficient, and if it exceeds 80% by weight, fluidity is lowered. A filler, a softening agent, an accelerator, an antiaging agent, a coloring agent, a flame retardant, and a coupling agent may be added to the adhesive for circuit connection of the present invention as appropriate. Further, it may be a multi-layered structure composed of two or more layers having different Tg (glass transition temperatures) when the circuit connecting adhesive of the present invention is a cured product. The substrate to be adhered using the adhesive for circuit connection of the present invention is not particularly limited as long as it has electrodes that require electrical connection, but ITO or the like used in liquid crystal displays. There are glass or plastic substrates on which electrodes are formed, printed wiring boards, ceramic wiring boards, flexible wiring boards, semiconductor silicon chips, etc., and they are used in combination as necessary. The conditions for connecting are not particularly limited, but the connection temperature is 90 to
The temperature is 250 ° C., the connection time is 1 second to 10 minutes, and it is appropriately selected depending on the intended use, the adhesive, and the substrate, and post-curing may be performed if necessary. The connection is performed by heating and pressurizing, but energy other than heat, such as light, ultrasonic waves, electromagnetic waves, etc., may be used if necessary.

[0025]

EXAMPLES The present invention will be specifically described below with reference to examples, but the scope of the present invention is not limited to these examples. (Preparation of Surface Treated Particles A) A 1% by weight methanol solution of γ-glycidoxypropylmethyldimethoxysilane was provided with a nickel layer having a thickness of 0.2 μm on the surface of the particles having polystyrene as the nucleus, and the outside of this nickel layer. And thickness 0.
Conductive particles having an average particle size of 4 μm and provided with a gold layer of 04 μm were added and stirred at 25 ° C. for 10 minutes. After filtering conductive particles, 5
It was dried at 0 ° C. for 15 minutes to obtain surface-treated particles A. (Preparation of surface-treated particles B) A 3 wt% methanol solution of a bisphenol A type epoxy resin is provided with a nickel layer having a thickness of 0.2 μm on the surface of particles having polystyrene as a nucleus, and a nickel layer having a thickness of 0 is formed outside the nickel layer. Add conductive particles with an average particle size of 5 μm with a gold layer of 0.04 μm, and add at 50 ° C. for 5
Stir for minutes. After separating the conductive particles by filtration, the particles were dried at 80 ° C. for 5 minutes to obtain surface-treated particles B. A PET (polyethylene terephthalate) film in which the conductive particles A and B were respectively blended in the following formulation, and one surface of which had a thickness of 50 μm was surface-treated using a simple coating machine (manufactured by Tester Sangyo Co., Ltd.) Then, the adhesive for circuit connection was prepared by drying with hot air at 70 ° C. for 10 minutes.

(Example 1) Phenoxy resin (PKHC,
Union Carbide Co., Ltd. trade name, average molecular weight 4
5,000) 50 g, dicyclohexyl methacrylate as a radically polymerizable compound 48 g, phosphoric acid ester acrylate 2 g as a phosphoric acid ester compound,
3 g of 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and further 3% by volume of the surface-treated particles A was mixed and dispersed. A polyethylene terephthalate film having a thickness of 50 μm, which has been surface-treated on one side, is applied using a simple coater, dried at 70 ° C. for 10 minutes, and has a thickness of 30 μm.
An adhesive for circuit connection was obtained.

(Example 2) Phenoxy resin (PKHC,
Union Carbide Co., Ltd. trade name, average molecular weight 4
5,000) 50 g, isocyanuric acid ethylene oxide modified diacrylate 46 g, phosphate ester acrylate 4 g, 2,5-dimethyl-2,5-bis (2
3 g of -ethylhexanoylperoxy) hexane was dissolved and compounded using methyl ethyl ketone as a solvent, and 3% by volume of surface-treated particles B was compounded and dispersed. A polyethylene terephthalate film having a thickness of 50 μm, one surface of which was surface-treated, was applied using a simple coating machine and dried at 70 ° C. for 10 minutes to obtain a circuit connecting adhesive having a thickness of 30 μm.

(Example 3) Phenoxy resin (PKHC,
Union Carbide Co., Ltd. trade name, average molecular weight 4
5,000) 25 g, polyurethane resin 25 g, dicyclohexyl methacrylate 48 g, phosphoric acid ester acrylate 2 g, 2,5-dimethyl-2,5-
Bis (2-ethylhexanoylperoxy) hexane
3 g was dissolved and compounded with methyl ethyl ketone as a solvent, and further 3% by volume of surface-treated particles B were compounded and dispersed. Thickness 50
It was applied to a polyethylene terephthalate film having a surface treated on one side having a thickness of μm by using a simple coater and dried at 70 ° C. for 10 minutes to obtain an adhesive for circuit connection having a thickness of 30 μm.

Comparative Example An adhesive for circuit connection was prepared by using untreated particles as the surface-treated particles A of Example 1.

(Production of Circuit Connection Structure) The circuit connection material was slit into a width of 1.5 mm and temporarily connected on a glass substrate on which ITO was formed as an electrode at 80 ° C. for 5 seconds and 1 MPa. did. The PET supporting substrate was peeled off, and a TCP electrode having an electrode width of 50 μm and a space of 50 μm was aligned with this, and main connection was performed under the conditions of 150 ° C., 20 seconds and 4 MPa.

(Characteristic evaluation method) Connection resistance: Multimeter TR manufactured by Advantest Corporation
The resistance between adjacent circuits was measured using the 6848 at a constant current of 1 mA. The connection resistance is 30 ° C at the initial stage after connection.
The value after standing for 60 hours at 60% RH was measured. The results are shown in Table 1.

[0032]

[Table 1]

In Examples 1 to 3 of the present invention, the connection resistance was low after standing and was good, but in Comparative Examples in which surface-treated particles were not used, the connection resistance after standing was significantly increased. In addition, after the adhesive for circuit connection was produced, it was left at 25 ° C. for 30 days and then a circuit connection structure was produced in the same manner as in the example. As a result, a circuit connection containing conductive particles surface-treated with a compound having an epoxy group The adhesive has the composition of Examples 1 to 3,
The connection resistance (initial) was 2.1 to 3.8Ω, which showed good storage stability. However, the connection resistance of the connection structure using the conductive particles not surface-treated with the compound having an epoxy group of the comparative example is 20 to 200Ω, and the storage stability is poor.

[0034]

EFFECTS OF THE INVENTION According to the present invention, a circuit connecting adhesive having good storage stability (pot life) can be obtained even if it is left standing after the circuit connecting adhesive is prepared. With respect to the connection temperature of 170 ° C. of the adhesive for circuit connection, it is possible to connect at a lower temperature of 150 ° C., and it is possible to obtain a good connection structure with little variation in connection resistance after storage of the adhesive.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05K 1/14 H05K 1/14 J // C09C 1/00 C09C 1/00 1/56 1/56 3/00 3 / 00 (72) Inventor Hiroshi Ono 48 Wada, Tsukuba City, Ibaraki Prefecture F-term in Hitachi Chemical Co., Ltd. Research Laboratory 4J037 AA02 AA04 CB09 CB11 CB12 CB13 CB16 CB18 CB19 CB22 CC16 CC17 CC23 CC30 EE02 EE12 EE33 EE35 EE43 EE47 FF 4J040 DD071 EB081 EB111 ED001 EE061 EF001 EG001 EH031 HD24 JA03 JB10 KA07 KA12 KA13 KA32 LA09 NA20 5E344 CD06 EE21 5F044 LL09 RR17 5G301 DA02 DA03 DA05 DA10 DA18 DA29 DA42 DA51 DA57 DD03

Claims (4)

[Claims] 1. An adhesive for circuit connection, which is interposed between substrates having circuit electrodes facing each other and pressurizes the substrates having circuit electrodes facing each other to electrically connect the electrodes in the pressing direction. The adhesive for circuit connection is characterized in that the adhesive contains a radically polymerizable compound and conductive particles surface-treated with a compound having at least one epoxy group. 2. The adhesive for circuit connection according to claim 1, which contains a compound that generates radicals by light or heating. 3. The adhesive for circuit connection according to claim 1, further comprising a phosphoric acid ester compound. 4. A connection structure in which an adhesive for circuit connection is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. A body, wherein the circuit connecting adhesive is the body.
A circuit connection structure which is the adhesive for circuit connection according to any one of claims 1 to 3.