JP4967276B2 - Circuit connection material, circuit terminal connection structure and connection method - Google Patents

Description

  The present invention relates to a circuit connection material that is interposed between circuit electrodes facing each other, pressurizes the circuit electrodes facing each other, and electrically connects only the electrodes in the pressing direction, a circuit terminal connection structure, and a connection method About.

Epoxy resin adhesives are widely used in various applications such as electricity, electronics, architecture, automobiles and airplanes because of their high adhesive strength and excellent water resistance and heat resistance.
Among them, the one-pack type epoxy resin adhesive is used in the form of a film, a paste, or a powder because it is not necessary to mix the main agent and the curing agent and is easy to use. In this case, it is common to obtain specific performance by various combinations of epoxy resins, curing agents and modifiers. However, such an epoxy resin film adhesive is excellent in workability, but is insufficient in terms of low temperature fast curing.

As a low-temperature fast-curing adhesive, a radical-polymerizable adhesive is known (for example, Patent Document 1), but when low-temperature curability is important, a curing agent having a low decomposition temperature (half-life temperature) (peroxidation) ) Is used, there is a problem that storage stability is lowered. An adhesive containing an epoxy resin and an amine imide compound that generates a base by light irradiation has also been proposed as a low-temperature fast-curing adhesive (for example, Patent Documents 2 and 3). In this adhesive, the amine imide compound is blended as a curing agent for the epoxy resin.
In addition, although photocationic curing has been proposed as a curing method by light irradiation and low-temperature heating (for example, Patent Document 4), there are problems with corrosion to metal members and toxicity of the catalyst.
WO98 / 44067 brochure JP 2001-279216 A JP 2003-26772 A WO00 / 46315 brochure

  An object of the present invention is to provide a circuit connecting material excellent in low-temperature fast curing property and storage stability.

As a result of diligent research in view of the above problems, the present inventors derived from a photobase generator by combining a radical polymerizable adhesive and a photobase generator that generates a base by light irradiation together with a radical polymerization initiator. It was found that this base promotes the decomposition of the radical polymerization initiator, thereby improving the low-temperature rapid curing of the adhesive and excellent storage stability when light is blocked. Thus, the present invention has been completed.
According to the present invention, the following circuit connection materials and the like are provided.
1. A circuit connecting material that is interposed between opposing circuit electrodes, pressurizes the opposing circuit electrodes, and electrically connects only the electrodes in the pressurizing direction, and includes the following components (1) to (3): Contains circuit connection material.
(1) radical polymerizable substance (2) radical polymerization initiator (3) photobase generator that generates a base by light irradiation 1 wherein the photobase generator is one or more compounds selected from the group consisting of carbamic acid ester derivatives, oxime ester derivatives, amine imide derivatives, imidazolium salt derivatives, quaternary ammonium salt derivatives, α-aminoketone derivatives, and nifedipine derivatives. Circuit connection material.
3. Furthermore, the circuit connection material of 1 or 2 containing a thermoplastic resin.
4). 4. The circuit connecting material according to 3, wherein the thermoplastic resin is selected from phenoxy resin, polyester resin, polyurethane resin, polyester urethane resin, polyvinyl butyral resin, polyvinyl formal resin, polyamide resin, polyimide resin, and polyacrylic resin.
5. Furthermore, the circuit connection material as described in any one of 1-4 containing electroconductive particle.
6). The first circuit member having the first connection terminal and the second circuit member having the second connection terminal are arranged to face the first connection terminal and the second connection terminal, and The circuit connection material according to any one of 1 to 5 is interposed between the first connection terminal and the second connection terminal that are arranged to face each other, and only the first connection terminal and the second connection terminal that are arranged to face each other. A circuit terminal connection structure in which is electrically connected.
7). The circuit connection material according to any one of the above 1 to 5 is disposed on a first circuit member having a first connection terminal, and after irradiating light from above the circuit connection material, the second connection terminal is A circuit terminal connection method in which a second connection member having a first connection terminal and a second connection terminal, which are arranged to face each other and are heated and pressurized to face each other, are electrically connected.
8). A first circuit member having a first connection terminal and a second circuit member having a second connection terminal are disposed so that the first connection terminal and the second connection terminal are opposed to each other, and the opposed arrangement is performed. The circuit connection material according to any one of 1 to 5 described above is interposed between the first connection terminal and the second connection terminal, and the first connection is disposed opposite to the substrate by applying pressure while heating simultaneously with light irradiation. A circuit terminal connection method for electrically connecting only the terminal and the second connection terminal.

  ADVANTAGE OF THE INVENTION According to this invention, the circuit connection material excellent in low-temperature quick curing property and storage stability can be provided.

  As the radically polymerizable substance (1) used in the present invention, a known substance can be used without particular limitation as long as it is a compound that is polymerized by a radical represented by a styrene compound, but an acryloyl group in the molecule. Alternatively, a compound having two or more methacryloyl groups (hereinafter referred to as (meth) acryloyl groups) in the molecule or a maleimide compound is more preferable.

Specifically, epoxy (meth) acrylate oligomer, urethane (meth) acrylate oligomer, polyether (meth) acrylate oligomer, oligomer such as polyester (meth) acrylate oligomer, trimethylolpropane tri (meth) acrylate, polyethylene glycol di ( (Meth) acrylate, polyalkylene glycol di (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, neopentyl glycol di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Isocyanuric acid modified bifunctional (meth) acrylate, isocyanuric acid modified trifunctional (meth) acrylate, 2,2'-di (meth) acryloyloxydiethyl phosphate Polyfunctional (meth) acrylate compounds such as 2- (meth) acryloyloxyethyl acid phosphate.
These can be used alone or in combination. If necessary, a polymerization inhibitor such as hydroquinone or methyl ether hydroquinone may be appropriately used.
Moreover, when it has a dicyclopentenyl group and / or a tricyclodecanyl group and / or a triazine ring, since heat resistance improves, it is preferable.

  The maleimide compound contains at least two maleimide groups in the molecule. For example, 1-methyl-2,4-bismaleimidebenzene, N, N′-m-phenylenebismaleimide, N, N′— p-phenylene bismaleimide, N, N′-m-toluylene bismaleimide, N, N′-4,4-biphenylene bismaleimide, N, N′-4,4- (3,3′-dimethyl-biphenylene) 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-diphenyl ether bismaleimide N, N′-3,3′-diphenylsulfone bismaleimide, 2,2-bis (4- (4-maleimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-4-8 (4 -Maleimidophenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidophenoxy) phenyl) decane, 4,4'-cyclohexylidene-bis (1- (4maleimidophenoxy) -2-cyclohexylbenzene, Examples include 2,2-bis (4- (4-maleimidophenoxy) phenyl) hexafluoropropane, etc. These can be used alone or in combination.

As the radical polymerization initiator (2) used in the present invention, known compounds such as conventionally known peroxides and azo compounds can be used. From the viewpoint of stability, reactivity, and compatibility, 1 Peroxides with a minute half-life temperature of 90 to 175 ° C. and a molecular weight of 180 to 1,000 are preferred.
Specifically, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxynoedecanoate, t-hexylper Oxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl -2,5-di (2-ethylhexanoylperoxy) hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyneohepta Noate, t-amylperoxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amino Peroxy-3,5,5-trimethylhexanoate, 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate , T-amylperoxyneodecanoate, t-amylperoxy-2-ethylhexanoate, 2,2′-azobis-2,4-dimethylvaleronitrile, 1,1′-azobis (1-acetoxy- 1-phenylethane), 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyronitrile, 4,4 '-Azobis (4-cyanovaleric acid), 1,1'-azobis (1-cyclohexanecarbonitrile), t-hexylperoxyisopropyl monocarbonate, t- Tilperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di (3-methylbenzoylperoxy) Hexane, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, dibutylperoxytrimethyl Examples include adipate, t-amyl peroxy normal octoate, t-amyl peroxy isononanoate, t-amyl peroxybenzoate, benzoyl peroxide, and di- (3-methylbenzoyl) peroxide.
These compounds may be used alone or as a mixture of two or more compounds.

  (2) The addition amount of the radical polymerization initiator is 0.05 to 30 parts by mass, preferably 0.1 to 20 parts by mass with respect to (1) 100 parts of the radical polymerizable substance. . When the addition amount is less than 0.05 parts by mass, there is a concern about insufficient curing, and when it exceeds 30 parts by mass, the standing stability may be lowered.

The (3) photobase generator used in the present invention is not particularly limited as long as it is a compound that generates a base by light irradiation. However, the carbamic acid ester derivative, oxime ester derivative, amine imide derivative, imidazolium salt derivative, 4 A quaternary ammonium salt derivative, α-aminoketone derivative, and nifedipine derivative are more preferable from the viewpoint of efficiently generating a base with respect to light irradiation.
See, for example, Chemistry & Technology of UV & EB Formulation for Coatings, Inks & Paints, Ed. by G. Bradley, John Wiley and Sons Ltd. (1998), carbamic acid ester derivatives, oxime ester derivatives, and quaternary ammonium salt derivatives described in p479 to p545. Further, α-aminoacetophenone derivatives described in JP-A-11-71450, amine imide derivatives described in WO2002 / 051905, imidazolium salt derivatives described in JP2003-212856, and JP 1 And dihydropyridine derivatives described in No. -53771 (hereinafter referred to as nifedipine derivatives).

  The addition amount of the (3) photobase generator of the present invention is preferably 0.01 to 200 parts by weight, more preferably 0.02 to 150 parts by weight with respect to 100 parts by weight of the (1) radical polymerizable substance. When the photobase generator is less than 0.01 parts by weight, the heat resistance tends to be lowered, and when it exceeds 200 parts by weight, the film physical properties tend to be lowered.

The circuit connection material of the present invention can further contain a thermoplastic resin. The thermoplastic resin is not particularly limited, but the main chain skeleton or side chain of the resin contains a polar group such as a hydroxyl group, an ether group, an ester group, a urethane group, an amide group, an imide group, or a carboxyxyl group. Resins are preferred from the viewpoint of adhesiveness. Specifically, phenoxy resin, polyester resin, polyurethane resin, polyester urethane resin, polyvinyl butyral resin, polyvinyl formal resin, polyamide resin, polyimide resin, polyacrylic resin, and the like can be used. Further, a polymer obtained by modifying the polymer with a radical polymerizable functional group is more preferable because heat resistance is improved.
The molecular weight of these polymers is not particularly limited, but the general weight average molecular weight is preferably from 5,000 to 150,000, particularly preferably from 10,000 to 80,000. If this value is less than 5,000, the film formability tends to be inferior, and if it exceeds 150,000, the compatibility with other components tends to deteriorate. The amount used is preferably (1) 20 to 320 parts by weight per 100 parts by weight of the radically polymerizable compound.

Even if the circuit connection material of the present invention does not have conductive particles, connection can be obtained by direct contact of circuit electrodes facing each other at the time of connection. However, when conductive particles are contained, more stable connection can be obtained.
Examples of the conductive particles include metal particles such as Au, Ag, Ni, Cu, and solder, carbon, and the like. In order to obtain a sufficient pot life, the surface layer is preferably Au, Ag, or a platinum group noble metal, preferably Au. More preferred.
Further, the surface of a transition metal such as Ni may be coated with a noble metal such as Au. In addition, the conductive layer described above is formed by coating or the like on non-conductive glass, ceramic, plastic (polystyrene, etc.), the outermost layer is precious metal, the core is plastic, and in the case of hot-melt metal particles, heating Since it has deformability by pressurization, it is preferable because the contact area with the electrode is increased at the time of connection and the reliability is improved.
The amount of the conductive particles used is preferably 0.1 to 30% by volume, more preferably 0.1 to 10% by volume with respect to 100 volumes of the circuit connecting material. If this value is less than 0.1% by volume, the conductivity tends to be inferior, and if it exceeds 30% by volume, a short circuit tends to occur. The volume% is determined based on the volume of each component before curing at 23 ° C., but the volume of each component can be converted from weight to volume using specific gravity.

  Furthermore, it can contain a polymerization inhibitor represented by fillers, softeners, accelerators, anti-aging agents, colorants, flame retardants, thixotropic agents, coupling agents, aminoxyl derivatives and phenol derivatives. .

  In the circuit connection material of the present invention, (3) a sensitizer may be used in combination for the purpose of improving the base generation efficiency of the photobase generator. As a sensitizer to be used, a known singlet sensitizer and triplet sensitizer can be used as long as they do not adversely affect the curable composition. For example, aromatic compound derivatives such as naphthalene, anthracene, and pyrene, carbazole derivatives, benzophenone derivatives, thioxanthone derivatives, and coumarin derivatives are preferably used. The amount of the sensitizer used should refer to the absorption wavelength and molar extinction coefficient of the sensitizer, but generally (3) 0.01 to 5 parts by weight with respect to 1 part by weight of the photobase generator. 0.1 to 2 parts by weight is particularly preferable. When the sensitizer is less than 0.01 parts by weight, the light absorption efficiency is low, and when it exceeds 5 parts by weight, there is a possibility that light does not reach the entire curable composition.

  In the circuit connection material of the present invention, (3) rather than the photobase generator functioning as a curing agent, (2) by promoting the decomposition of the radical polymerization initiator, the reaction of the entire circuit connection material is promoted. Low temperature fast curability is improved. Usually, the decomposition of the radical polymerization initiator is promoted by the basic compound, but when the basic compound itself is added, the storage stability is lowered. Therefore, in the present invention, storage stability and low-temperature rapid curing are possible by generating a basic compound by light irradiation.

In the connection method of the present invention, a first circuit member having a first connection terminal and a second circuit member having a second connection terminal are arranged so that the first connection terminal and the second connection terminal are opposed to each other. The circuit connection material of the present invention is interposed between the first connection terminal and the second connection terminal arranged opposite to each other, and only the first connection terminal and the second connection terminal arranged opposite to each other are electrically connected. Connect.
As such a circuit member, a chip component such as a semiconductor chip, a resistor chip or a capacitor chip, a substrate such as a printed circuit board, or the like is used. The circuit member is usually provided with a large number of connection terminals (or a single connection terminal in some cases).

  In order to obtain better electrical connection, it is preferable that at least one surface of the circuit electrode (connection terminal) is made of a metal selected from gold, silver, tin, and a platinum group. The surface layer is selected from gold, silver, platinum group, or tin, and these may be used in combination. Moreover, it is good also as a multilayer structure combining several metals like copper / nickel / gold.

As a connection method, after arranging the circuit connection material on the first circuit member having the first connection terminal by temporary pressure bonding, after irradiating light from above the circuit connection material, the second connection terminal The 2nd circuit member which has can be arrange | positioned facing and can be made to adhere | attach by pressurizing, heating.
In addition, in the case where the first circuit member is a transparent base material from the ultraviolet region to the visible region, after placing the circuit connection material on the first circuit member having the first connection terminal by provisional pressure bonding, A second circuit member having a second connection terminal can be disposed oppositely, heated and pressurized from above the second circuit member, and irradiated with light from below the first circuit member for bonding.
The curing condition is usually 1 to 120 seconds at 100 to 200 ° C. under a pressure of 0.1 to 10 MPa in the case of heating, but is not limited thereto. The light irradiation is preferably in the wavelength range of 150 to 750 nm, and a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, or a metal halide lamp can be used. 0.01 to 10 J / cm ² , but is not limited thereto.

  The circuit connection material of the present invention can be used in the form of a paste when it is liquid at room temperature (25 ° C.). In the case of a solid at room temperature, it may be heated and used, or may be made into a paste using a solvent. The solvent that can be used is not particularly limited as long as it does not adversely affect the curability and exhibits sufficient solubility, but a solvent having a boiling point of 50 to 150 ° C. at normal pressure is preferable. If the boiling point is less than 50 ° C., it may volatilize if left at room temperature, which limits the use in an open system. Moreover, when a boiling point exceeds 150 degreeC, there exists a possibility that removal of a solvent may become difficult.

  The circuit connection material of the present invention can be used in the form of a film. A solution prepared by adding a solvent or the like to the adhesive composition as necessary is applied onto a peelable substrate such as a fluororesin film, a polyethylene terephthalate film, or a release paper, or a substrate such as a nonwoven fabric is impregnated with the solution. Can be used as a film after removing the solvent and the like. Use in the form of a film is more convenient from the viewpoint of handleability.

  Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto.

<Synthesis of carbamic acid ester>
2,4-Dinitrobenzyl alcohol (2.00 g, 10 mmol) and 1,8-diaza-bicyclo (5,4,0) undecene-7 (0.10 g, 0.6 mmol) were dissolved in 20 g of tetrahydrofuran to obtain cyclohexyl. Isocyanate
(1.27 g, 10 mmol) was added dropwise at room temperature. After completion of the dropwise addition, the mixture was stirred at room temperature for 48 hours, and a white precipitate was formed. This was filtered off, recrystallized with ethyl acetate, and dried with a vacuum dryer to obtain a carbamate compound. The yield was 2.23 g and the yield was 68%.

<Synthesis of oxime ester>
9-Fluorenone oxime (2.00 g, 10 mmol) and pyridine (0.80 g, 10 mmol) were dissolved in 20 g of tetrahydrofuran and diethylcarbamoyl chloride was dissolved.
(1.36 g, 10 mmol) was added dropwise while cooling in an ice bath. After completion of the dropwise addition, the mixture was stirred at room temperature for 24 hours, and a white precipitate was formed. When 200 g of water was added thereto, a pale yellow precipitate was deposited. This was filtered off, recrystallized with acetone, and dried with a vacuum dryer to obtain an oxime ester compound. The yield was 2.58 g and the yield was 88%.

<Synthesis of amine imide>
Add p-nitrobenzoic acid methyl ester (2.00 g, 11 mmol), N, N-dimethylhydrazine (0.66 g, 11 mmol), phenylglycidyl ether (1.66 g, 11 mmol) to tert-butanol (15.0 g). After stirring at 50 ° C. for 10 hours and further stirring at room temperature (25 ° C.) for 48 hours, a white precipitate was formed. This was filtered off, washed twice with ethyl acetate, and dried in a vacuum dryer to obtain an amine imide compound. The yield was 3.67 g, and the yield was 85%.

<Synthesis of imidazolium salt>
p-Nitrophenacyl bromide (2.00 g, 8.2 mmol) was dissolved in acetone (20 g) and 1,2-dimethylimidazole (0.79 g, 8.2 mmol) dissolved in acetone (5 g) was dissolved therein. The solution was slowly added, and then stirred at room temperature for 2 hours to precipitate white crystals. This was filtered, washed twice with acetone, and then dried under vacuum at 60 ° C. for 5 hours to obtain an imidazolium bromide salt (yield 2.62 g).
The above-mentioned imidazole bromide salt (2.00 g, 5.8 mmol) was dissolved in a methanol / water (15 g / 15 g) solution, and tetraphenylborate sodium salt (2.01 g) dissolved in water (5.0 g). 5.8 mmol) solution was added slowly. A white slurry-like precipitation was observed with the addition, and the mixture was further stirred at room temperature for 5 hours. This was filtered, dissolved in acetone (20 g) and recrystallized to obtain the desired imidazolium tetraphenylborate (imidazolium salt) (yield 3.23 g).

<Synthesis of quaternary ammonium salt>
p-Nitrophenacyl bromide (2.00 g, 8.2 mmol) was dissolved in acetone (20 g), and N, N-dimethylbenzylamine (1.10 g, 8.2 mmol) dissolved in acetone (5 g) was dissolved therein. The solution was slowly added, and then stirred at room temperature for 2 hours to precipitate white crystals. This was filtered, washed twice with acetone, and then dried under vacuum at 60 ° C. for 5 hours to obtain an ammonium bromide salt (yield 2.73 g).
Ammonium bromide salt (2.00 g, 5.3 mmol) was dissolved in a methanol / water (15 g / 15 g) solution, and tetraphenylborate sodium salt (1.84 g) dissolved in water (5.0 g). 5.3 mmol) was added slowly. A white slurry-like precipitation was observed with the addition, and the mixture was further stirred at room temperature for 5 hours. This was filtered, dissolved in acetone (20 g) and recrystallized to obtain the desired quaternary ammonium salt (yield 2.98 g).

(Examples 1-7, Comparative Examples 1-2)
As the thermoplastic resin, a phenoxy resin and a urethane resin were used. 40 g of phenoxy resin (PKHC, trade name of Union Carbide, average molecular weight 45,000) was dissolved in 60 g of methyl ethyl ketone to obtain a solution having a solid content of 40% by weight. The urethane resin is uniformly mixed with 450 parts by weight of polybutylene adipate diol having an average molecular weight of 2000, 450 parts by weight of polyoxytetramethylene glycol having an average molecular weight of 2000, and 100 parts by weight of 1,4-butylene glycol in 4000 parts by weight of methyl ethyl ketone. Then, a urethane resin having a weight average molecular weight of 150,000 obtained by adding 390 parts by weight of diphenylmethane diisocyanate and reacting at 70 ° C. was used. (1) As radical polymerizable substances, isocyanuric acid EO-modified diacrylate (M-215, trade name manufactured by Toa Gosei Co., Ltd.), urethane acrylate (AT-600, trade name manufactured by Kyoeisha Chemical Co., Ltd.) and 2- (meth) Acryloyloxyethyl phosphate (light ester P-2M, trade name, manufactured by Kyoeisha Co., Ltd.), (2) di- (3-methylbenzoyl) peroxide having a 10-hour half-life temperature of 73.1 ° C. as a radical polymerization initiator (Nyper BMT, Nippon Oil & Fats Co., Ltd. trade name), (3) The compounds shown in Table 1 were used as photobase generators. Further, a nickel layer having a thickness of 0.2 μm is provided on the surface of a particle having polystyrene as a nucleus, and a gold layer having a thickness of 0.02 μm is provided outside the nickel layer, and the conductive material has an average particle diameter of 4 μm and a specific gravity of 2.5. Particles were made.
It mix | blends as shown in Table 1 by solid weight ratio, Furthermore, 1.5 volume% of electroconductive particles are mix | blended and disperse | distributed, and it apply | coats to a 80-micrometer-thick fluororesin film using a coating device, 70 degreeC, hot air for 10 minutes A film adhesive having an adhesive layer thickness of 20 μm was obtained by drying.

α-アミノケトン：２-ベンジル-２-ジメチルアミノ-１-（４-モルフォリノフェニル）-ブタノン−１
ニフェジピン：ジメチル ２,６−ジメチル−４−（ｏ-ニトロフェニル）-１,４−ジヒドロ−３,５−ピリジンジカルボキシレート

α-aminoketone: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1
Nifedipine: Dimethyl 2,6-dimethyl-4- (o-nitrophenyl) -1,4-dihydro-3,5-pyridinedicarboxylate

[Measurement of adhesive strength and connection resistance]
Using the film-like adhesive obtained by the above manufacturing method, a flexible circuit board (TCP) having 500 copper circuits having a line width of 25 μm, a pitch of 50 μm, and a thickness of 18 μm, and a thin layer of indium oxide (ITO) of 0.2 μm The formed glass (thickness 1.1 mm, surface resistance 20 Ω / □) is heated with a thermocompression bonding apparatus (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.) at a temperature of 130 ° C. and 3 MPa for 10 seconds. The connection was made by applying pressure and connecting over a width of 2 mm. At this time, the adhesive surface of the film-like circuit connecting material is preliminarily connected to the ITO glass by heating and pressurizing at 70 ° C. and 1 MPa for 3 seconds, and then the fluororesin film is peeled off to form a film surface comprising the circuit connecting composition. The sample was irradiated with 1.0 J / cm ² of ultraviolet rays using an ultraviolet irradiation device (manufactured by USHIO INC.) Having a high-pressure mercury lamp. Then, it connected with FPC which is another to-be-adhered body, and produced the connection body. The resistance value between adjacent circuits of this connection body was measured with a multimeter immediately after bonding and after being held in a high-temperature and high-humidity bath at 85 ° C. and 85% RH for 168 hours. The resistance value was shown as an average of 37 resistances between adjacent circuits.

  Moreover, the adhesive strength of this connection body was measured by a 90-degree peeling method according to JIS-Z0237 and evaluated. Here, Tensilon UTM-4 (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Baldwin Co., Ltd. was used as a measuring device for adhesive strength.

  Table 2 shows the results of measurement of the adhesive strength and connection resistance of the connection body performed as described above.

  The adhesive compositions obtained in Examples 1-7 had good connection resistance and adhesion at a heating temperature of 130 ° C. immediately after adhesion and after being held in a high-temperature and high-humidity bath at 85 ° C. and 85% RH for 168 hours. It was found to show strength and good properties. In Comparative Example 1 in which the photobase in the present invention does not use a generator, the connection resistance value immediately after bonding is high. The rise of was seen. Moreover, it became clear that adhesive force also fell compared with Examples 1-7, and low temperature curability and high reliability are securable by using the photobase generator of this invention.

(Comparative Example 2)
TCP and ITO were thermocompression bonded at 130 ° C., 3 MPa, and 10 s in the same manner as in Example 4 except that ultraviolet irradiation was omitted when the film adhesive obtained in Example 4 was produced. The connection strength and connection resistance of the connection body obtained as described above were measured. The connection resistance was 4.6Ω and the bond strength was 150 N / m. Both the connection resistance and the bond strength were irradiated with ultraviolet rays. Compared to 4, it worsened.

(Example 8)
The film adhesive obtained in Example 1 was vacuum packaged and allowed to stand at 40 ° C. for 3 days, and then TCP and ITO were thermocompression bonded at 130 ° C., 3 MPa, and 10 s as in Example 1. It was. When the adhesion strength and connection resistance of the connection body as described above were measured, it was found that the adhesion strength was 780 N / m, the connection resistance was 1.5Ω, and the storage stability was excellent.

(Comparative Example 3)
Comparative Example 1 except that the radical polymerization initiator of Comparative Example 1 was changed to di-n-propyl peroxydicarbonate (Perroyl NPP, product name manufactured by NOF Corporation) having a 10-hour half-life temperature of 40.3 ° C. A film-like adhesive was prepared in the same manner as in No. 1, vacuum-packed, and allowed to stand at 40 ° C. for 3 days. Then, the film-like adhesive before and after being left was treated with TCP and ITO at 130 ° C. and 3 MPa as in Example 1. Thermocompression bonding was performed in 10 seconds. Table 3 shows the results of measurement of the adhesive strength and connection resistance of the connection body performed as described above.

  Although the film-like adhesive of Comparative Example 3 exhibited good characteristics in both connection resistance and adhesive strength before standing, the resistance increased and the adhesive strength decreased after standing at 40 ° C. for 3 days. From this result, it was found that the curing progressed during standing at 40 ° C., and the standing stability was poor.

The circuit connection material of the present invention can be widely used as an anisotropic adhesive for electrical and electronic use.

Claims (5)

A circuit connection material that is interposed between circuit electrodes facing each other, pressurizes the circuit electrodes facing each other, and electrically connects only the electrodes in the pressurizing direction, and includes the following components (1) to (3) :
(1) Radical polymerizable substance that is a compound having two or more acryloyl groups or methacryloyl groups in the molecule (2) Radical polymerization initiator that is a peroxide or azo compound (3) A photobase that generates a base by light irradiation Generating agent
A circuit connection material containing
The photobase generator is one or more compounds selected from the group consisting of carbamic acid ester derivatives, oxime ester derivatives, amine imide derivatives, imidazolium salt derivatives, quaternary ammonium salt derivatives, α-aminoketone derivatives, nifedipine derivatives,
Furthermore, the circuit connecting material contains a thermoplastic resin,
The circuit connecting material, wherein the thermoplastic resin is selected from phenoxy resin, polyester resin, polyurethane resin, polyester urethane resin, butyral resin, and acrylic resin. Furthermore, the circuit connecting material according to claim 1, further comprising conductive particles. The first circuit member having the first connection terminal and the second circuit member having the second connection terminal are arranged to face the first connection terminal and the second connection terminal, and The circuit connection material according to claim 1 or 2 is interposed between the first connection terminal and the second connection terminal arranged opposite to each other, and the first connection terminal and the second connection terminal arranged opposite to each other. Only the circuit terminal connection structure that is electrically connected. A circuit connection material according to any one of claims 1 to 3 is arranged on a first circuit member having a first connection terminal, and light irradiation is performed on a film surface made of the circuit connection material. A circuit terminal connection method in which only the second connection terminal and the second connection terminal that are arranged to face each other by arranging the second circuit member having the connection terminals facing each other and pressurizing while heating are connected. A first circuit member having a first connection terminal and a second circuit member having a second connection terminal are disposed so that the first connection terminal and the second connection terminal are opposed to each other, and the opposed arrangement is performed. The circuit connection material according to any one of claims 1 to 4 is interposed between the first connection terminal and the second connection terminal, and the first and the second connection terminals are arranged opposite to each other by applying pressure while heating simultaneously with light irradiation. Circuit terminal connection method in which only the connection terminal and the second connection terminal are electrically heated.