JP4877365B2 - Circuit connection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit connecting method capable of connecting two circuit members each other with sufficient adhesive strength even if one of the two circuit members to be connected is either a TCP or a FPC, capable of reducing connection resistance between circuit electrodes, and capable of sufficiently preventing the connection resistance from rising with the passage of time. <P>SOLUTION: This circuit connecting method is to connect the first circuit member 20 having a first circuit electrode 22 to the second circuit member 31 having a second circuit electrode 32 to form the TCP or the FPC using a circuit connecting material 10 to connect both electrodes by disposing them face to face. The circuit connecting material contains a thermosetting composition and a photo-curing composition, and can be connected to either the TCP or the FPC, and when the second circuit member is the TCP, both members are connected after the value of the ratio of the area S<SB>b</SB>of the circuit connecting material after heating and pressing it to its initial area S<SB>a</SB>is set to 1.3-3.0 by applying light, and when the second circuit member is the FPC, the members are connected without applying light. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a circuit connection method.

  Conventionally, circuit connection materials have been used for connection between a liquid crystal display and a tape carrier package (TCP) and between a printed circuit board and TCP (for example, see Patent Document 1).

  In recent years, especially in the field of liquid crystal displays, higher density and higher definition of circuits have progressed, and the width of circuit electrodes in circuit members and the interval between circuit electrodes have become extremely narrow. Therefore, a flexible printed circuit board (FPC) in which the circuit density is relatively easier than that of TCP is being used as a circuit board. When the FPC is connected to a liquid crystal display or the like, the above circuit connection material is used, but separate circuit connection materials are used for connecting the FPC and TCP.

  However, the number of devices that use FPC is increasing, and it is necessary to manufacture a TCP connection display in which TCP and a liquid crystal display are connected and an FPC connection display in which an FPC and a liquid crystal display are connected using the same apparatus. In this case, the circuit connection material has to be exchanged between a model using TCP and a model using FPC. Therefore, in order to shorten the exchange time of the circuit connection material, there is an increasing demand for a circuit connection method that can be used for both TCP and FPC.

International Publication WO98 / 44067 Pamphlet

  However, the conventional circuit connection material can only satisfy the characteristics suitable for the connection of either one of TCP and FPC, and it has been difficult to use it for both TCP and FPC. Specifically, when connecting the FPC, the circuit height of the FPC is lower than the circuit height of the TCP, so it is necessary to increase the fluidity of the circuit connection material for FPC. If the circuit connection material is used for TCP connection, the fluidity is too high and bubbles are entrained, and sufficient adhesion strength between circuit members cannot be obtained. There was a problem that a significant rise occurred. On the other hand, when TCP is connected, TCP connection can be made without any problem with the circuit connection material for TCP without increasing the fluidity of the circuit connection material, but this circuit connection material for TCP can be used for FPC connection. When used, there is a problem that the connection resistance between the circuit electrodes facing each other increases due to insufficient flow.

  The present invention has been made in view of the above-mentioned problems of the prior art, and even if one of the two circuit members to be connected is either TCP or FPC, the circuit members can be connected with sufficient adhesive strength, It is an object of the present invention to provide a circuit connection method capable of sufficiently reducing the connection resistance between circuit electrodes and sufficiently preventing an increase in connection resistance over time.

  As a result of intensive studies to achieve the above object, the present inventors have used the circuit connection material containing a thermosetting composition and a photocurable composition that is cured by light irradiation. Has been found to be possible, and the present invention has been completed.

That is, the present invention provides a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode and constituting a tape carrier package or a flexible printed board. A circuit connection method for connecting a first circuit member and a second circuit member using a circuit connection material for connecting the circuit electrode and the second circuit electrode in a state of facing each other. The connection material contains a thermosetting composition and a photocurable composition that is cured by light irradiation, and can be connected to both the tape carrier package and the flexible printed circuit board. In case of constituting a tape carrier package, a circuit connecting material of 5 mm × 5 mm and a thickness of 35 μm is sandwiched between glasses so as to be in the same thickness direction as the glass, and 150 ° C., 2 MP surface after the relative to the area S _a of the one to have contact with the surface of the glass before the initial circuit connecting material for heating pressurized, subjected to heat and pressure when performing condition for 10 seconds heating and pressing of a The fluidity (S _b / S _a ) value represented by the ratio of the area S _b of the film is 1.3 to 3.0 by curing the photo-curable composition by irradiating the circuit connecting material with light. Then, the first circuit member and the second circuit member are connected by heat and pressure , and when the second circuit member constitutes the flexible printed board, the circuit connection material is irradiated with light. The circuit connection method is characterized in that the first circuit member and the second circuit member are connected by heating and pressurization .

  In such a circuit connection method, when FPC is used as the second circuit member, the circuit connection material is used with sufficient fluidity without irradiating the circuit connection material with light. For this reason, an increase in connection resistance between the opposing circuit electrodes is sufficiently prevented. In addition, when TCP is used as the second circuit member, after the photocurable composition is cured by light irradiation to reduce the fluidity of the circuit connection material, entrainment of bubbles and the like is sufficiently prevented by heating. In this state, the first circuit member and the second circuit member can be connected. For this reason, the first circuit member and the second circuit member can be connected to each other with sufficient adhesive strength, and the connection resistance between the circuit electrodes facing each other can be sufficiently prevented from increasing with time. It becomes possible to do.

The present invention also provides a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode and constituting a tape carrier package or a flexible printed board. A circuit connection material for connecting a circuit electrode and a second circuit electrode in a state of facing each other, comprising a thermosetting composition and a photocurable composition that is cured by light irradiation, By curing the photocurable composition in the circuit connecting material by light irradiation, the value of the fluidity (S _b / S _a ) represented by the ratio of the area S _b after heating and pressing to the area S _a of Provided is a circuit connection material characterized in that it can be set to 1.3 to 3.0 and can be connected to either a tape carrier package or a flexible printed board.

  Such a circuit connecting material is used in a state having sufficient fluidity without performing light irradiation when FPC is used as the second circuit member. For this reason, an increase in connection resistance between the opposing circuit electrodes is sufficiently prevented. In addition, when TCP is used as the second circuit member, after the photocurable composition is cured by light irradiation to reduce fluidity, the entrainment of bubbles and the like is sufficiently prevented by heating. It becomes possible to connect the one circuit member and the second circuit member. For this reason, the first circuit member and the second circuit member can be connected to each other with sufficient adhesive strength, and the connection resistance between the circuit electrodes facing each other can be sufficiently prevented from increasing with time. It becomes possible to do.

The circuit connecting material to be used in a circuit connection method of the present invention, flowability represented by the ratio of the area S _b of the heating after pressurization to the initial area S _a of the circuit connecting material (S b _/ S _a) Can be set to 1.3 to 3.0 by curing the photocurable composition in the circuit connecting material by light irradiation.

By allowing the fluidity of the circuit connecting material to be adjusted as described above by light irradiation, it is possible to prevent air bubbles from being sufficiently prevented when TCP is connected to the first circuit member. Thus, the circuit members can be connected to each other. In particular, when the circuit connecting material overall response rate after the light irradiation is 5-50%, the fluidity represented by a ratio of an area S _b of the heating after pressurization to the initial area S _a of the circuit connecting material When the value of (S _b / S _a ) is 1.3 to 3.0, the fluidity can be easily and reliably lowered by light irradiation for a relatively short time, and the TCP and the first circuit Connection with a member can be performed more efficiently.

  Furthermore, in the circuit connection material used in the circuit connection method of the present invention, the thermosetting composition preferably contains one of an epoxy resin and a radical polymerizable compound. As a result, the adhesive strength between the circuit members can be made more sufficient, the connection resistance between the circuit electrodes can be more sufficiently reduced, and the increase in connection resistance over time can be more sufficiently prevented. it can.

  Moreover, in the circuit connection material used in the circuit connection method of the present invention, the photocurable composition contains any one of a photocation reactive compound, a photo radical reactive compound, and a photo anion reactive compound. Is preferred. Thereby, when connecting TCP to a 1st circuit member, the fluidity | liquidity of a circuit connection material can be reduced easily and reliably.

  Furthermore, the circuit connection material used in the circuit connection method of the present invention preferably further contains conductive particles. By using the conductive particles, the connection resistance between the circuit electrodes facing each other can be more sufficiently reduced.

  According to the present invention, even if one of the two circuit members to be connected is either TCP or FPC, the circuit members can be connected with sufficient adhesive strength, the connection resistance between the circuit electrodes can be sufficiently reduced, and It is possible to provide a circuit connection method that can sufficiently prevent an increase in connection resistance over time.

It is a schematic cross section which shows one Embodiment of the film-form circuit connection material used with the circuit connection method of this invention. (A)-(d) is a series of process drawings which each connect FPC and a 1st circuit board. (A)-(e) is a series of process drawings which each connect TCP and a 1st circuit board.

  Hereinafter, embodiments of the circuit connection method of the present invention will be described in detail. In the following description, (meth) acrylate means acrylate or a corresponding methacrylate.

  The circuit connection material used in the circuit connection method of the present invention is for electrically connecting a first circuit member and a second circuit member made of a tape carrier package or a flexible printed circuit board, It contains a curable composition and a photocurable composition that is cured by light irradiation.

  Such a circuit connecting material is used in a state having sufficient fluidity without performing light irradiation when FPC is used as the second circuit member. For this reason, an increase in connection resistance between the opposing circuit electrodes is sufficiently prevented. In addition, when TCP is used as the second circuit member, after the photocurable composition is cured by light irradiation to reduce fluidity, the entrainment of bubbles and the like is sufficiently prevented by heating. It becomes possible to connect the one circuit member and the second circuit member. For this reason, the first circuit member and the second circuit member can be connected to each other with sufficient adhesive strength, and the connection resistance between the circuit electrodes facing each other can be sufficiently prevented from increasing with time. It becomes possible to do.

  Here, the thermosetting composition according to the present invention starts curing by heating to a predetermined temperature or higher, and contains either one of an epoxy resin and a radical polymerizable compound. preferable. As a result, the adhesive strength between the circuit members can be made more sufficient, the connection resistance between the circuit electrodes can be more sufficiently reduced, and the increase in connection resistance over time can be more sufficiently prevented. it can. In particular, when the thermosetting composition contains a radical polymerizable compound, it can be cured at a lower temperature and in a shorter time than when the thermosetting composition contains an epoxy resin.

  The epoxy resin preferably contains two or more epoxy groups in the molecule. Examples of such an epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and phenol novolac. Type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type An epoxy resin, an aliphatic chain epoxy resin, etc. are mentioned. These epoxy resins may be halogenated or hydrogenated. These epoxy resins may be used alone or in combination of two or more.

  When an epoxy resin is used in the thermosetting composition, a curing agent capable of curing the epoxy resin is used. Examples of such a curing agent include an anion polymerizable catalyst type curing agent, a cationic polymerizable catalyst type curing agent, a polyaddition type curing agent, and the like. These can be used alone or in combination of two or more.

  Examples of anionic or cationic polymerizable catalyst-type curing agents include tertiary amines, imidazoles, hydrazide compounds, boron trifluoride-amine complexes, onium salts (sulfonium salts, ammonium salts, etc.), amine imides, diaminos, and the like. Examples include maleonitrile, melamine and derivatives thereof, polyamine salts, dicyandiamide, and the like, and these modified products can also be used. Examples of the polyaddition type curing agent include polyamines, polymercaptans, polyphenols, and acid anhydrides.

  Further, from the viewpoint of reactivity and storage stability, these hardeners are coated with a polymer material such as polyurethane or polyester, a metal thin film such as nickel or copper, and an inorganic material such as calcium silicate to form a microcapsule. It is preferable to use a microcapsule-type latent curing agent.

  It is preferable that the addition amount of such a hardening | curing agent is 5-100 weight part with respect to 100 weight part of epoxy resins. When the addition amount is less than the lower limit value, the reactivity is insufficient and the reliability tends to decrease, and when the addition amount exceeds the upper limit value, the storage stability tends to decrease.

  The radically polymerizable compound is a compound having a functional group that is polymerized by radicals, and examples of such radically polymerizable compounds include (meth) acrylate resins, maleimide resins, citraconic imide resins, and nadiimide resins. These can be used alone or in combination of two or more. Moreover, the radically polymerizable compound may be used in any state of a monomer and an oligomer, and a monomer and an oligomer may be mixed and used.

  Specific examples of the (meth) acrylate resin include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, etherene glycol di (meth) acrylate, and diethylene glycol di (meth) acrylate. , Trimethylolpropane tri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydroxy-1,3-diaacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2 , 2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylate tricyclodecanyl (meth) acrylate, tris (acryloxyethyl) isocyanurate, urethane (meth) acrylate Rate, and isocyanuric acid ethylene oxide-modified diacrylate. These can be used alone or in combination of two or more. Moreover, you may use radical polymerization inhibitors, such as hydroquinone and methyl ether hydroquinone, in the range by which sclerosis | hardenability is not impaired as needed.

  The maleimide resin has at least one maleimide group in the molecule. Examples of such a maleimide resin include phenylmaleimide, 1-methyl-2,4-bismaleimidebenzene, N, N ′. -M-phenylene bismaleimide, 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-diphenyl ether 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- Examples thereof include cyclohexylbenzene and 2,2-bis (4- (4-maleimidophenoxy) phenyl) hexafluoropropane. These can be used alone or in combination of two or more.

  The citraconic imide resin is obtained by polymerizing a citraconic imide compound having at least one citraconic imide group in the molecule. Examples of the citraconic imide compound include phenyl citraconic imide, 1-methyl- 2,4-biscitraconimide benzene, 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-dimethyldiphenylmethane) biscitraconimide, N, N'-4,4- (3 , 3-Diethyldiphenylmethane) biscitraconimide, N, N′-4,4-diphenylmethanebiscitraco Imido, N, N′-4,4-diphenylpropane biscitraconimide, N, N′-4,4-diphenyl ether biscitraconimide, N, N′-4,4-diphenylsulfone biscitraconimide, 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. These can be used alone or in combination of two or more.

  The nadiimide resin is obtained by polymerizing a nadiimide compound having at least one nadiimide group in the molecule. Examples of such a nadiimide compound include phenyl nadiimide, 1-methyl-2,4- Bisnadiimidebenzene, N, N′-m-phenylenebisnadiimide, N, N′-p-phenylenebisnadiimide, N, N′-4,4-biphenylenebisnadiimide, 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-diphenylmethane bisnadiimide, N, N'-4,4-diphenylpropane bisnadiimide, N, N'-4,4 Diphenyl ether bisnadiimide, N, N′-4,4-diphenylsulfone bisnadiimide, 2,2-bis (4- (4-nadiimidophenoxy) 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-na And diimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4- (4-nadiimidophenoxy) phenyl) hexafluoropropane, and the like. These can be used alone or in combination of two or more.

  When using these radically polymerizable compounds, it is preferable to use a radically polymerizable compound having a phosphate ester structure in combination because the adhesive strength to circuit electrodes (such as inorganic substances such as metals) can be improved. A radical polymerizable compound having a phosphoric ester structure is obtained as a reaction product of phosphoric anhydride and 2-hydroxyethyl (meth) acrylate, and specifically, mono (2-methacryloyloxyethyl) acid. Examples thereof include phosphate and di (2-methacryloyloxyethyl) acid phosphate. These can be used alone or in combination of two or more.

  The addition amount of the radical polymerizable compound having a phosphate ester structure is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the other radical polymerizable compound, and 0.5 to 5 parts by weight. More preferably.

  When a radical polymerizable compound is used in the thermosetting composition of the present invention, a polymerization initiator that generates free radicals upon heating is used. As such a polymerization initiator, any compound that generates free radicals upon heating can be used without particular limitation, and a peroxide compound, an azo compound, or the like can be used. Such a polymerization initiator can be appropriately selected depending on the intended connection temperature, connection time, pot life, etc., but the half-life time of 10 hours is 40 ° C. or more, and the half-life temperature of 1 minute is 180 ° C. or less. An organic peroxide is preferable, and an organic peroxide having a half-life of 10 hours at a temperature of 50 ° C. or higher and a half-life of 1 minute at a temperature of 170 ° C. or lower is particularly preferable.

  Specific examples of the organic peroxide include diacyl peroxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, hydroperoxide, silyl peroxide, and the like. Among these, from the viewpoint of suppressing corrosion of the circuit electrode, those having a chlorine ion or organic acid content of 5000 ppm or less contained in the polymerization initiator are preferred, and those having less organic acid generated after heat decomposition are more preferred. From this point of view, peroxyesters, dialkyl peroxides, hydroperoxides, and silyl peroxides contain 5000 ppm or less of chlorine ions and organic acids in the polymerization initiator, and less organic acids are generated after thermal decomposition. Since corrosion of the connection terminal of a member can be suppressed, it is especially preferable. From the viewpoint of improving the stability of the circuit connecting material, it is preferable to use a polymerization initiator having a weight retention of 20% by weight or more after being left open for 24 hours at room temperature and normal pressure.

  Here, as diacyl peroxide, isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic peroxide Examples thereof include oxide, benzoyl peroxytoluene, and benzoyl peroxide.

  Examples of peroxydicarbonate include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxymethoxyperoxydicarbonate, di ( 2-ethylhexyl peroxy) dicarbonate, dimethoxybutyl peroxydicarbonate, di (3-methyl-3-methoxybutylperoxy) dicarbonate and the like.

  Peroxyesters include cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxynoedecanoate, and t-hexyl. Peroxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2- Ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate Nate, t-butylperoxyisobutyrate, 1,1-bis (t-butylperoxy) cyclohexane, -Hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanonate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di (m-toluoyl par Oxy) hexane, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxyacetate and the like.

  Peroxyketals include 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t- Butyl peroxy) -3,3,5-trimethylcyclohexane, 1,1- (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) decane and the like.

  Dialkyl peroxides include α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and t-butyl. Cumyl peroxide and the like.

  Examples of the hydroperoxide include diisopropylbenzene hydroperoxide and cumene hydroperoxide.

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

  These polymerization initiators that generate free radicals upon heating can be used alone or in combination of two or more thereof, and further, a decomposition accelerator, an inhibitor, and the like may be mixed and used. In addition, those obtained by coating these polymerization initiators with a polyurethane-based or polyester-based polymer substance and making them into microcapsules are preferable because the pot life is extended.

  Moreover, it is preferable that the addition amount of this polymerization initiator is 0.05-10 weight part with respect to 100 weight part of radically polymerizable compounds, and it is especially preferable that it is 0.1-5 weight part. When the addition amount is less than the above lower limit value, the reaction rate tends to be low and the reliability tends to decrease, and when it exceeds the above upper limit value, the storage stability tends to decrease.

  Furthermore, it is preferable that the content rate of the thermosetting composition in the circuit connection material used with the circuit connection method of this invention is 10 to 60 weight% on the basis of the total amount of solid content in a circuit connection material. When the content is less than the lower limit, the connection resistance tends to increase, and when the content exceeds the upper limit, the fluidity tends not to be controlled well.

  The circuit connection material used in the circuit connection method of the present invention contains the thermosetting composition described above and a photocurable composition that is cured by light irradiation.

  It is preferable that the photocurable composition concerning this invention contains any one of a photocation reactive compound, a photo radical reactive compound, and a photo anion reactive compound. Thereby, when connecting TCP to a 1st circuit member, the fluidity | liquidity of a circuit connection material can be reduced easily and reliably.

  The above-mentioned photocation reactive compound is a compound having a functional group that is polymerized depending on the cation species, and examples of such a photocation reactive compound include cyclic ether compounds such as epoxy, oxetane, and tetrahydrofuran, vinyl ether compounds, and the like. These can be used alone or in combination of two or more.

  Here, the epoxy resin demonstrated previously can be used as an epoxy compound.

  The oxetane compound has at least one oxetane ring in the molecule. Examples of the oxetane compound having one oxetane ring in the molecule include compounds represented by the following general formula (1).

In the general formula (1), R ¹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.), a fluoroalkyl group having 1 to 6 carbon atoms, or an allyl group. , Aryl group, furyl group, thienyl group and the like. R ² represents an alkyl group having 1 to 6 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.), an alkenyl group having 2 to 6 carbon atoms (1-propenyl group, 2-propenyl group, 2-methyl- 1-propenyl group, 2-methyl-2-propenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, etc.), groups having an aromatic ring (phenyl group, benzyl group, fluorobenzyl group, methoxybenzyl group) , Phenoxyethyl group, etc.), C2-C6 alkylcarbonyl group (ethylcarbonyl group, propylcarbonyl group, butylcarbonyl group, etc.), C2-C6 alkoxycarbonyl group (ethoxycarbonyl group, propoxycarbonyl group, butoxy) Carbonyl group etc.) or N-alkylcarbamoyl group having 2 to 6 carbon atoms (ethylcarbamoyl group, propylcarbamoyl group, Tilcarbamoyl group, pentylcarbamoyl group, etc.).

  Examples of the oxetane compound having two oxetane rings in the molecule include compounds represented by the following general formula (2).

In the general formula (2), ^{R 1} has the same meaning as ^{R 1} in the general formula (1). R ³ represents a linear or branched alkylene group (ethylene group, propylene group, butylene group, etc.), a linear or branched poly (alkyleneoxy) group (poly (ethyleneoxy) group, poly (propyleneoxy) ) Group), linear or branched unsaturated hydrocarbon group (propenylene group, methylpropenylene group, butenylene group, etc.), carbonyl group, alkylene group containing carbonyl group, alkylene group containing carboxyl group, carbamoyl group Or a polyvalent group selected from the groups represented by the following general formulas (2-1) to (2-12).

In the general formula (2-1), R ⁴ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.), an alkoxy group having 1 to 4 carbon atoms (methoxy group). Group, ethoxy group, propoxy group, butoxy group, etc.), halogen atom (chlorine atom, bromine atom, etc.), nitro group, cyano group, mercapto group, lower alkyl carboxyl group, carboxyl group or carbamoyl group.

In the above general formula (2-2), R ⁵ represents an oxygen atom, a sulfur atom, a methylene group, —NH—, —SO—, —SO ₂ —, —C (CF ₃ ) ₂ —, or —C ( CH _{3) 2} - shows a.

In the above general formula (2-3), R ⁶ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.), or an alkoxy group having 1 to 4 carbon atoms. (Methoxy group, ethoxy group, propoxy group, butoxy group, etc.), halogen atom (chlorine atom, bromine atom, etc.), nitro group, cyano group, mercapto group, lower alkyl carboxyl group, carboxyl group or carbamoyl group.

In the above general formula (2-4), R ⁵ represents an oxygen atom, a sulfur atom, a methylene group, —NH—, —SO—, —SO ₂ —, —C (CF ₃ ) ₂ —, —C (CH ₃ ) _2- or a divalent group represented by the following general formula (2-4a) or (2-4b).

In the above general formula (2-5) and general formula (2-6), R ⁸ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms (methyl group, ethyl group, propyl group, butyl group, etc.), carbon 1 to 4 alkoxy groups (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), halogen atom (chlorine atom, bromine atom, etc.), nitro group, cyano group, mercapto group, lower alkyl carboxyl group, carboxyl group Or a carbamoyl group is shown. R ⁸ may be substituted on the naphthalene ring by 2 to 4 units.

  In the said General formula (2-12), n shows the integer of 0-10. The compound represented by the general formula (2-12) may be a mixture of a plurality of compounds having different n.

Moreover, as an oxetane compound which has two oxetane rings in a molecule | numerator, as a preferable example other than the compound mentioned above, the compound represented by following General formula (3) is mentioned. Incidentally, in the general formula (3), ^{R 1} has the same meaning as ^{R 1} in the general formula (1).

As a compound which has 3-4 oxetane rings in a molecule | numerator, the compound etc. which are represented by following General formula (4) are mentioned, for example.

In the general formula (4), R ¹ has the same meaning as R ¹ in the general formula (1), m represents 3 or 4, and R ⁹ represents the following general formulas (4-1) to (4- 3) a branched alkylene group having 1 to 12 carbon atoms such as a group represented by 3), a branched poly (alkyleneoxy) group such as a group represented by the following general formula (4-4), and the like.

In the general formula (4-1), R ¹⁰ represents a lower alkyl group (such as a methyl group, an ethyl group, or a propyl group).

  In the above general formula (4-4), p represents an integer of 1 to 10.

  Preferable specific examples of the oxetane compound used as the photocation reactive compound include compounds represented by the following general formulas (5) to (10).

In the above general formulas (8) to (10), R ¹¹ represents a methyl group or an ethyl group.

  In addition to these, compounds having 1 to 4 oxetane rings having a relatively high molecular weight and a molecular weight of about 1,000 to 5,000 can also be used. Further, as a polymer containing oxetane, a polymer having an oxetane ring in a side chain (for example, see K. Sato, A. Kameyama and T. Nishikubo, Macromolecules, 25, 1198 (1992)) can be used in the same manner. . These oxetane compounds can be used alone or in combination of two or more.

  Moreover, as a vinyl ether compound which can be used as a photocation reactive compound, an alkyl vinyl ether compound, an alkenyl vinyl ether compound, an aryl vinyl ether compound etc. are mentioned, for example.

  In the present invention, when these photocation reactive compounds are used, a photoinitiator that generates a cationic species by light irradiation is used. Such photoinitiators include aromatic diazonium salts, sulfonium salts, iodonium salts, onium salts such as phosphonium salts and selenonium salts, metal arene complexes and complex compounds such as silanol / aluminum complexes, benzoin tosylate, and o-nitro. Benzyl tosylate and the like can be used. As the counter anion of the onium salt, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, tetrakis (pentafluorophenyl) borate and the like are used.

  Moreover, it is preferable that the addition amount of this photoinitiator is 0.5-20 weight part with respect to 100 weight part of photocation reactive compounds.

  As the photoradical reactive compound, the radically polymerizable compound described above can be used, and (meth) acrylate resin, maleimide resin, citraconic resin, nadiimide resin, and the like can be used. These can be used alone or in combination of two or more. Moreover, the radically polymerizable compound may be used in any state of a monomer and an oligomer, and a monomer and an oligomer may be mixed and used.

  When using such a radically polymerizable compound, a photoinitiator (photoradical generator) that generates radicals by light irradiation is used. Such photoinitiators include benzoin ethers such as benzoin ethyl ether and isopropyl benzoin ether; ketones such as benzyl, benzophenone and hydroxycyclohexyl phenyl ketone; and bisimidazoles. These can be used alone or in combination of two or more. In addition to these photoinitiators, sensitizers such as amine compounds, sulfur compounds, and phosphorus compounds may be used as necessary.

  Moreover, it is preferable that the addition amount of this photoinitiator is 0.5-20 weight part with respect to 100 weight part of photoradical reactive compounds.

  The photoanion-reactive compound is a compound that is polymerized with a basic compound, and as such a photoanion-reactive compound, the cyclic ether compounds such as epoxy, oxetane, and tetrahydrofuran described above can be used.

  Moreover, when using this photoanion reactive compound, the photoinitiator which a base generate | occur | produces by irradiation is used.

  Such a photoinitiator is a compound that generates a base when irradiated with radiation, and the generated base increases the curing reaction rate of the photoanion-reactive compound. As the base to be generated, a strongly basic compound is preferable in terms of reactivity and curing speed. In general, a pKa value that is a logarithm of an acid dissociation constant is used as a basic index, and a base having a pKa value in an aqueous solution of 7 or more is preferable, and a base of 9 or more is more preferable.

  The photoinitiator is preferably a compound that generates a base when irradiated with light having a wavelength of 150 to 750 nm. From the viewpoint of efficiently generating a base when a general light source is used, light having a wavelength of 250 to 500 nm is used. More preferably, the compound generates a base upon irradiation.

  Specific examples of such photoinitiators include imidazole derivatives such as imidazole, 2,4-dimethylimidazole, and 1-methylimidazole; piperazine derivatives such as piperazine and 2,5-dimethylpiperazine; piperidine, 1,2-dimethyl Piperidine derivatives such as piperidine; proline derivatives; trialkylamine derivatives such as trimethylamine, triethylamine and triethanolamine; pyridine derivatives substituted with an amino group or alkylamino group at the 4-position such as 4-methylaminopyridine and 4-dimethylaminopyridine Pyrrolidine derivatives such as pyrrolidine and n-methylpyrrolidine; alicyclic amine derivatives such as triethylenediamine and 1,8-diazabiscyclo (5,4,0) undecene-1 (DBU); benzylmethylamine and benzyldimethylamine Emissions, and the like benzylamine derivatives such as benzyl diethylamine. Further, quaternary ammonium salt derivatives described in Journal of Photopolymer Science and Technology 12, 313-314 (1999), Chemistry of Materials 11, 170-176 (1999), etc. can also be used. . Since such a quaternary ammonium salt derivative generates a highly basic trialkylamine upon irradiation with actinic rays, it is optimal for curing a photoanion reactive compound such as an epoxy resin. Furthermore, a carbamate derivative described in Journal of American Chemical Society 118, 12925 (1996), Polymer Journal 28, 795 (1996), or a primary amino group is generated by irradiation with active light. An oxime derivative or the like can also be used.

  Furthermore, an α-aminoketone compound can be most suitably used in the present invention as a photoinitiator that generates a base upon irradiation. Specifically, as such α-aminoketone compound, commercially available 2-methyl-1 (4- (methylthio) phenyl) -2-morpholinopropan-1-one (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: Irgacure) 907), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1-one (manufactured by Ciba Specialty Chemicals, trade name: Irgacure 369), hexaarylbisimidazole derivative (halogen, Substituents such as an alkoxy group, a nitro group, and a cyano group may be substituted with a phenyl group), benzoisoxazolone derivatives, and the like.

  This α-aminoketone compound does not have the effect of accelerating the curing of the photoanion-reactive compound due to steric hindrance before irradiation with radiation, but irradiation with radiation results in dissociation of the α-aminoketone compound to reduce steric hindrance. Therefore, it is guessed that the hardening acceleration | stimulation effect | action of a photoanion reactive compound is shown.

  When these photoinitiators are used, a basic compound can be generated by photo-Fries rearrangement, photo-Claisen rearrangement (photo-Cleisen rearrangement), Curtius rearrangement (Curtius rearrangement), and Stevens rearrangement (Stevens rearrangement). Thus, the photoanion reactive compound can be cured.

  Furthermore, as the photoinitiator, an amine imide compound can be used in addition to the compounds described above. As such an amine imide compound, a compound capable of generating a base by irradiation with actinic rays can be used without particular limitation. Specifically, for example, it is represented by the following general formula (11) or (12). Compounds.

In the general formulas (11) and (12), R ^{12 to} R ¹⁴ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an alkylidene group having 1 to 8 carbon atoms. A phenyl group substituted with a C 4-8 cycloalkyl group, a C 4-8 cycloalkenyl group, a C 1-6 phenoxyalkyl group, a phenyl group, an electron donating group and / or an electron withdrawing group. Benzyl group, electron donating group and / or benzyl group substituted with electron withdrawing group. Here, as a C1-C8 alkyl group, an isopropyl group, an isobutyl group, t-butyl group etc. are included other than a linear alkyl group. Among these substituents, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 6 to 8 carbon atoms, and a phenoxyalkyl group having 1 to 6 carbon atoms are provided from the viewpoint of ease of synthesis and solubility of amine imide. preferable. R ¹⁵ represents an alkyl group having 1 to 5 carbon atoms, a hydroxyl group, a cycloalkyl group having 4 to 8 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a phenyl group.

Ar ¹ in the general formula (11) represents an aromatic group represented by the following general formulas (11-1) to (11-14), and Ar ² in the general formula (12) represents the following general formula Aromatic groups represented by formulas (12-1) to (12-9) are shown.

In the general formulas (11-1) to (11-14) and the general formulas (12-1) to (12-9), R ^{16 to} R ⁴⁷ are each independently a hydrogen atom or a carbon number of 1 to 8. An alkyl group, an alkoxy group having 1 to 8 carbon atoms, an alkylthio group having 1 to 8 carbon atoms, an alkylidene group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 8 carbon atoms, a cycloalkenyl group having 4 to 8 carbon atoms, Amino group, alkyl group having 1 to 6 carbon atoms, dialkylamino group having 1 to 3 carbon atoms, morpholino group, mercapto group, hydroxyl group, hydroxyalkyl group having 1 to 6 carbon atoms, fluorine atom, chlorine atom, bromine atom, etc. Halogens, ester groups having 1 to 6 carbon atoms, carbonyl groups having 1 to 6 carbon atoms, aldehyde groups, cyano groups, trifluoromethyl groups, cyano groups, nitro groups, benzoyl groups, phenyl groups, electron donating groups and / or Represents an electron-withdrawing phenyl group group-substituted, electron-donating groups and / or electron withdrawing benzyl group which group is substituted. In the general formulas (11-1) to (11-14), U to Z each independently represent a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom. Further, in the above general formulas (12-1) to (12-9), A, B, D, and E each independently represent a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom, which are each a carbon atom, You may couple | bond with a nitrogen atom, a C1-C6 alkyl group, an oxygen atom, and a sulfur atom.

  The synthesis | combination of the said amine imide compound can be performed by a well-known method. See, for example, Encyclopedia of Polymer Science and Engineering, John Wiley & Sons Ltd. (1985), Volume 1, p740, obtained from the reaction of the corresponding carboxylic acid ester with a halogenated hydrazine and sodium alkoxide, or the reaction of a carboxylic acid ester with hydrazine and an epoxy compound. be able to. In view of the ease of synthesis and safety, a synthesis method from the corresponding carboxylic acid ester, hydrazine and an epoxy compound is particularly preferred. The synthesis temperature and synthesis time are not particularly limited as long as the starting materials to be used are not decomposed. Generally, the desired amine imide compound is obtained by stirring at a temperature of 0 to 100 ° C. for 30 minutes to 7 days. Obtainable.

  In addition to the above-mentioned photoinitiators that generate bases upon irradiation, imidazolium salts can also be used. Examples of the imidazolium salt include compounds represented by the following general formulas (13) and (14).

In the general formulas (13) and (14), R ^{48 to} R ⁵¹ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an alkylidene group having 1 to 8 carbon atoms. , A cycloalkyl group having 4 to 8 carbon atoms, a cycloalkenyl group having 4 to 8 carbon atoms, a phenoxyalkyl group having 1 to 6 carbon atoms, a phenylalkyl group having 1 to 6 carbon atoms, a cyanoalkyl group having 1 to 6 carbon atoms A phenyl group substituted with a hydroxyalkyl group having 1 to 6 carbon atoms, a phenyl group, an electron donating group and / or an electron withdrawing group, a benzyl group, an electron donating group and / or a benzyl group substituted with an electron withdrawing group Nitro group, cyano group, mercapto group, thiomethyl group, fluorine atom, bromine atom, chlorine atom, iodine atom.

Ar ¹ in the general formula (13) and Ar ² in the general formula (14) have the same meanings as Ar ¹ in the general formula (11) and Ar ² in the general formula (12), respectively.

Further, X in the general formula (13) and (14) ^- indicates a borate represented by the dialkyl dithiocarbamate or the following general formula 1 to 6 carbon atoms (13-1).

In the general formula (13-1), R ^{52 to} R ⁵⁵ are each independently a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, a phenyl group, a fluorophenyl group substituted with at least one fluorine atom, or An imidazole group is shown.

  Although the synthesis of the imidazolium salt can be carried out by a known method, considering the simplicity and safety of the synthesis, as shown in the following reaction formula (A), a halogenated alkyl ketone derivative and an imidazole derivative are used. A method of synthesizing an imidazolium salt by anion exchange reaction after synthesizing an imidazolium halogen salt is preferable.

  The synthesis temperature and synthesis time are not particularly limited as long as the starting materials to be used are not decomposed. Generally, the desired imidazolium salt is obtained by stirring at a temperature of 0 to 100 ° C. for 30 minutes to 7 days. A compound can be obtained. Since these compounds do not show reactivity with photoanion-reactive compounds in a state where they are not irradiated with radiation at room temperature, they have a feature of excellent storage stability at room temperature.

  The addition amount of the photoinitiator that generates a base upon irradiation with radiation is preferably 0.01 to 200 parts by weight, and 0.02 to 150 parts by weight with respect to 100 parts by weight of the photoanion-reactive compound. More preferably. When the addition amount is less than 0.01 part by weight, it tends to be difficult to reduce fluidity satisfactorily. On the other hand, when the added amount exceeds 200 parts by weight, properties as a film-like circuit connecting material, storage stability, physical properties of the film and the like tend to deteriorate.

  A sensitizer can also be added to the photocurable composition in the circuit connection material used in the circuit connection method of the present invention for the purpose of increasing the absorption and sensitivity of irradiated light. As such a sensitizer, a known singlet sensitizer or triplet sensitizer can be used as long as it does not adversely affect the photocurable composition.

  Specific examples of the sensitizer include, for example, aromatic compound derivatives such as naphthalene, anthracene, and pyrene, carbazole derivatives, aromatic carbonyl compounds, benzophenone derivatives, benzoin derivatives, thioxanthone derivatives, and coumarin derivatives. Among these, naphthalene derivatives, anthracene derivatives, and carbazole derivatives are particularly preferable as singlet sensitizers, and thioxanthone derivatives, benzophenone derivatives, and benzoin derivatives are particularly preferable as triplet sensitizers.

  Specific examples of these sensitizers include 1-methylnaphthalene, 2-methylnaphthalene, 1-fluoronaphthalene, 1-chloronaphthalene, 2-chloronaphthalene, 1-bromonaphthalene, 2-bromonaphthalene, 1 -Iodonaphthalene, 2-iodonaphthalene, 1-naphthol, 2-naphthol and aromatic groups represented by the above general formulas (11-1) to (11-14) and (12-1) to (12-9) The compound which has is mentioned.

  As the sensitizer, in addition to the above-mentioned compounds, 1-methoxynaphthalene, 2-methoxynaphthalene, 1,4-dicyanonaphthalene, anthracene, 1,2-benzanthracene, 9,10-dichloroanthracene, 9 , 10-dibromoanthracene, 9,10-diphenylanthracene, 9-cyanoanthracene, 9,10-dicyanoanthracene, 2,6,9,10-tetracyanoanthracene, carbazole, 9-methylcarbazole, 9-phenylcarbazole, 9 -Prop-2-ynyl-9H-carbazole, 9-propyl-9H-carbazole, 9-vinylcarbazole, 9H-carbazole-9-ethanol, 9-methyl-3-nitro-9H-carbazole, 9-methyl-3, 6-dinitro-9H-carbazole, 9-oct Noylcarbazole, 9-carbazolemethanol, 9-carbazolepropionic acid, 9-carbazolepropionitrile, 9-decyl-3,6-dinitro-9H-carbazole, 9-ethyl-3,6-dinitro-9H-carbazole, 9 -Ethyl-3-nitrocarbazole, 9-ethylcarbazole, 9-isopropylcarbazole, 9- (ethoxycarbonylmethyl) carbazole, 9- (morpholinomethyl) carbazole, 9-acetylcarbazole, 9-allylcarbazole, 9-benzyl-9H -Carbazole, 9-carbazole acetic acid, 9- (2-nitrophenyl) carbazole, 9- (4-methoxyphenyl) carbazole, 9- (1-ethoxy-2-methyl-propyl) -9H-carbazole, 3-nitrocarbazole 4 Hydroxycarbazole, 3,6-dinitro-9H-carbazole, 3,6-diphenyl-9H-carbazole, 2-hydroxycarbazole, 3,6-diacetyl-9-ethylcarbazole, benzophenone, 4-phenylbenzophenone, 4,4 ′ -Bis (dimethoxy) benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, 2-benzoylbenzoic acid methyl ester, 2-methylbenzophenone, 3-methylbenzophenone, 4- Methylbenzophenone, 3,3′-dimethyl-4-methoxybenzophenone, 2,4,6-trimethylbenzophenone, [4- (4-methylphenylthio) phenyl] -phenylmethanone, xanthone, thioxanthone, 2-chlorothioxone Sandone, 4-chlorothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 1-chloro-4-propoxythioxanthone, benzoin, benzoin methyl ether, benzoin ethyl ether, Examples include benzoin isopropyl ether, benzoin n-propyl ether, benzoin n-butyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethanone, and 2,2-diethoxy-1,2-diphenylethanone. These sensitizers can be used alone or in combination of two or more.

  The addition amount of the sensitizer needs to refer to the absorption wavelength and molar extinction coefficient of the sensitizer to be used, and is 0.01 to 10 parts by weight with respect to 100 parts by weight of the photoinitiator. Is more preferable, 0.1 to 5 parts by weight is more preferable, and 0.1 to 2 parts by weight is particularly preferable. By setting the addition amount in the above range, the light absorption efficiency and light transmittance can be improved.

  Moreover, it is preferable that the content rate of the photocurable composition in the circuit connection material used with the circuit connection method of this invention is 5 to 50 weight% on the basis of the total amount of solid content in a circuit connection material. If the content is less than the above lower limit value, the fluidity drop after light irradiation tends to be poor.If the content exceeds the upper limit value, the curing reaction proceeds too much by light irradiation, and a good connection is obtained. There is no tendency.

  Furthermore, it is preferable that the content rate of a photocurable composition is 5-100 weight part with respect to 100 weight part of thermosetting compositions. When the content is less than 5 parts by weight, the fluidity is not sufficiently lowered as compared with the case where the content is in the above range, and bubbles tend to be easily involved when connecting TCP. When the amount exceeds 100 parts by weight, the fluidity tends to be too low and the connection resistance tends to be higher than when the content is in the above range.

  The circuit connection material used in the circuit connection method of the present invention preferably contains conductive particles as well as the thermosetting composition and the photocurable composition described above.

  As such conductive particles, any conductive particles can be used as long as they have conductivity capable of obtaining electrical connection, and metal particles such as Au, Ag, Ni, Cu, Co, and solder can be used. Or carbon can be used. Moreover, what coat | covered nonelectroconductive glass, ceramics, plastics, etc. with electrically conductive substances, such as said metal particle, can also be used. At this time, the thickness of the conductive material layer to be coated is preferably 100 mm or more in order to obtain sufficient conductivity.

  Moreover, it is preferable that the addition amount of electroconductive particle is 0.1-30 volume part with respect to 100 volume part of solid content (adhesive composition) except the electroconductive particle in a circuit connection material, and 0.0. It is more preferably 1 to 20 parts by volume.

  The circuit connection material used in the circuit connection method of the present invention provides polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin, polyimide resin, xylene to impart film formability, adhesion, and stress relaxation during curing. It is preferable to further contain a polymer component such as a resin, a phenoxy resin, a polyurethane resin, or a urea resin. Such a polymer component preferably has a molecular weight of 10,000 to 10,000,000. Further, these polymer components may be modified with radically polymerizable functional groups, and in that case, the heat resistance of the circuit connecting material tends to be improved.

  The content of the polymer component is preferably 2 to 80% by weight, more preferably 5 to 70% by weight, and more preferably 10 to 60% by weight based on the total solid content in the circuit connecting material. Particularly preferred. When the content is less than 2% by weight, the stress relaxation and the adhesive force tend to be insufficient as compared with the case where the content is within the above range. When the content exceeds 80% by weight, the content is within the above range. Compared with the case where it exists in inside, it exists in the tendency for fluidity | liquidity to fall.

  The circuit connection material used in the circuit connection method of the present invention may further contain additives such as fillers, softeners, anti-aging agents, flame retardants, and coupling agents.

  Further, the use form of the circuit connection material used in the circuit connection method of the present invention is not particularly limited. For example, a solution in which each of the above components is dissolved and / or dispersed in a solvent such as toluene, MEK, or methyl acetate, or It can be used as a molded body (for example, a film-like circuit connecting material as shown below) formed by removing the solvent from this solution and molding it into a predetermined shape.

  Next, the film-like circuit connecting material will be described. The film-like circuit connection material is formed by molding the above-described circuit connection material into a film shape.

  As shown in FIG. 1, the film-like circuit connecting material 10 includes the thermosetting composition and the photocurable composition described above as essential components, and an adhesive including a polymer component and additives as necessary. For example, a material obtained by dissolving a circuit connecting material in a solvent is coated on a support (PET (polyethylene terephthalate) film or the like). It can produce by apply | coating using a construction apparatus and drying with hot air for the predetermined time at the temperature which the said thermosetting composition does not harden | cure. Moreover, it is preferable that the thickness of the film-form circuit connection material 10 is 10-50 micrometers.

  Next, about the connection method of the 1st circuit member and the 2nd circuit member using the said film-form circuit connection material 10, FIG.2 (a)-(d) and FIG.3 (a)-(e) are shown. It explains using.

  2A to 2D are a series of process diagrams for connecting the FPC and the first circuit member when the second circuit member is a flexible printed circuit board (FPC), and FIG. (E) to (e) are a series of process diagrams for connecting the TCP and the first circuit member when the second circuit member is a tape carrier package (TCP). In FIG. 1, FIGS. 2A to 2D and FIGS. 3A to 3E, the same or equivalent components are denoted by the same reference numerals.

  First, a method for connecting circuit members when the second circuit member is an FPC will be described.

  First, in addition to the film-like circuit connecting material 10, a first circuit member 20 and a second circuit member 30 made of FPC are prepared. Here, the first circuit member 20 includes a circuit board 21 and a circuit electrode 22 formed on one surface of the circuit board 21, and the second circuit member 30 includes a circuit board 31 and a circuit board. 31 and a circuit electrode 32 formed on one surface. Specific examples of the first circuit member 20 include a printed wiring board, a liquid crystal display, a plasma display, and an organic EL display.

  Next, as shown in FIG. 2A, the film-like circuit connecting material 10 is placed on the surface (circuit electrode forming surface) of the first circuit member 20 on which the circuit electrodes 22 are formed. When the film-like circuit connecting material 10 is adhered on a support (not shown), the first circuit is formed so that the film-like circuit connecting material 10 side faces the first circuit member 20. The member 20 is placed on the circuit electrode formation surface.

  Then, while heating the film-like circuit connecting material 10, pressure is applied in the directions of arrows A and B in FIG. 2A to temporarily connect the film-like circuit connecting material 10 to the first circuit member 20 (FIG. 2B. )reference). At this time, the heating temperature is a temperature at which the thermosetting resin composition in the film-like circuit connecting material 10 is not cured, that is, a temperature lower than the temperature at which curing is started.

  Subsequently, as shown in FIG. 2C, the second circuit member 30 is placed on the film-like circuit connection material 10 so that the second circuit electrode faces the first circuit member 20. In addition, when the film-form circuit connection material 10 has adhered on the support body (not shown), after peeling a support body, the 2nd circuit member 30 is mounted on the film-form circuit connection material 10. FIG.

  And while heating the film-form circuit connection material 10, it pressurizes in the arrow A and B direction of FIG.2 (c), the hardening process of the film-form circuit connection material 10 is performed, and this connection is performed. The heating temperature at this time is set to a temperature at which the thermosetting resin composition is cured. Thus, a circuit member connection structure is obtained.

  As described above, the film-shaped circuit connecting material 10 is heated at a temperature lower than the temperature at which the thermosetting resin composition starts to cure without performing light irradiation, whereby the photocurable resin composition and The thermosetting resin composition is not cured, and high fluidity is imparted to the film-like circuit connecting material 10. For this reason, when the connection structure of a circuit member is obtained by hardening | curing the thermosetting resin composition with a heat | fever at the time of this connection, the raise of the connection resistance between the circuit electrodes which oppose can fully be prevented.

  Next, a method for connecting circuit members when the second circuit member is TCP will be described.

  First, in addition to the film-like circuit connecting material 10, a first circuit member 20 and a second circuit member 40 made of TCP are prepared. The second circuit member 40 includes a circuit board 41 and a circuit electrode 42 formed on one surface of the circuit board 41.

  Next, as shown in FIG. 3A, the film-like circuit connecting material 10 is placed on the circuit electrode formation surface of the first circuit member 20. When the film-like circuit connecting material 10 is adhered on a support (not shown), the first circuit is formed so that the film-like circuit connecting material 10 side faces the first circuit member 20. The member 20 is placed on the circuit electrode formation surface.

  And while heating the film-form circuit connection material 10, it pressurizes in the arrow A and B direction of Fig.3 (a), and temporarily connects the film-form circuit connection material 10 to the 1st circuit member 20 (FIG.3 (b) )reference). At this time, the heating temperature is a temperature at which the thermosetting resin composition in the film-like circuit connecting material 10 is not cured, that is, a temperature lower than the temperature at which curing is started.

  Subsequently, as shown in FIG. 3C, the light source 50 is used to irradiate the entire film-like circuit connecting material 10 so that the fluidity of the film-like circuit connecting material 10 falls within a predetermined range. The photocurable composition is cured. In addition, when the film-form circuit connection material 10 has adhered on the support body (not shown), light irradiation is performed after peeling a support body.

  Thereafter, as shown in FIG. 3D, the second circuit member 40 is placed on the film-like circuit connection material 10 with the second circuit electrode facing the first circuit member 20. And while heating the film-form circuit connection material 10, it pressurizes in the arrow A and B direction of FIG.3 (d), the hardening process of the film-form circuit connection material 10 is performed, and this connection is performed. The heating temperature at this time is set to a temperature at which the thermosetting resin composition is cured. Thus, a circuit member connection structure is obtained.

  As described above, when the film-like circuit connecting material 10 is irradiated with light, the photocurable resin composition is cured, and the fluidity of the film-like circuit connecting material 10 is lowered. For this reason, when the thermosetting resin composition is cured by heat at the time of this connection, entrainment of bubbles and the like is sufficiently prevented. As a result, the first circuit member 20 and the second circuit member 40 can be connected to each other with sufficient adhesive strength, and the connection resistance between the circuit electrodes facing each other with time is sufficiently increased. Can be prevented.

  From the above, if the film-like circuit connecting material 10 is used, even if the second circuit member is either FPC or TCP, the circuit members can be connected with sufficient adhesive strength, and the connection resistance between the circuit electrodes is sufficiently high. In addition, the connection resistance can be sufficiently prevented from increasing with time.

The film-like circuit connecting material 10, after the light irradiation, flowability represented by the ratio of the area S _b of the heating after pressurization to the initial area S _a of the film-like circuit connecting material (S b _/ S _a ) Is 1.3 to 3.0, preferably 1.5 to 2.5. Here, the fluidity is such that the film-like circuit connecting material 10 having a thickness of 5 mm × 5 mm and a thickness of 35 μm is placed in the same thickness direction as that of the glass between two glasses of 15 mm × 15 mm and a thickness of 0.7 mm. scissors, 0.99 ° C., in the case of the 10 seconds heating and pressing under the conditions of 2 MPa, to the area S _a of the surface in contact with one of the glass at the initial of the film-like circuit connecting material 10 prior to the heat and pressure, indicating the ratio of the area _{S b} of the surface after the above heating and pressing _(S b / S _a). If the fluidity (S _b / S _a ) is less than the above lower limit value, the fluidity tends to be poor and a good connection tends not to be obtained. Tend to be inferior.

  The light irradiated to the film-like circuit connecting material 10 when connecting the TCP is preferably ultraviolet light, and the light source 50 is an ultra-high pressure mercury lamp, high-pressure mercury lamp, low-pressure mercury lamp, mercury xenon lamp, halogen lamp, or the like. Can do.

The dose of light is preferably in a range that can be controlled fluidity of the film-like circuit connecting material 10, for ^example, it is preferable to ^{0.5J / cm 2 ~20J / cm 2} . When the irradiation amount is less than 0.5 J / cm ² , compared to the case where the irradiation amount is within the above range, the fluidity is not sufficiently lowered, and bubbles tend to be easily involved when TCP is connected. When the irradiation amount exceeds 20 J / cm ² , compared to the case where the irradiation amount is within the above range, the fluidity tends to decrease too much and the connection resistance tends to increase, and the irradiation time becomes longer, so that the productivity is increased. There is a tendency to decrease.

  Moreover, it is preferable that the reaction rate as a whole of the film-form circuit connection material 10 at the time of connecting TCP is 5 to 50%. Moreover, it is preferable that the fluidity | liquidity of the circuit connection material at this time is 1.3-3.0. The reaction rate is determined by, for example, an infrared spectrophotometer (IR), the intensity ratio of the photocurable composition and the thermosetting composition before and after the light irradiation (the photocurable composition and the thermosetting before the light irradiation). The ratio of the strength of the curable composition to the strength of the photocurable composition and the thermosetting composition after light irradiation) can be calculated.

  In addition, in the example of the connection method of the said circuit member, although the connection structure of a circuit member is manufactured using the film-form circuit connection material 10, it replaces with the film-form circuit connection material 10, and the polymer component which forms a film A circuit connection material that does not include the above may be used. Even in this case, for example, if the circuit connection material is dissolved in a solvent, and the solution is applied to the first circuit member 20 and dried, it can be interposed between the first and second circuit members. Conditions such as the fluidity of the circuit connecting material, the heating temperature and the amount of light irradiation are the same as in the case where the film-like circuit connecting material 10 is used.

  In addition, when the film-like circuit connection material 10 (or circuit connection material) is irradiated with light, it may be irradiated at any stage before the main connection of the TCP, but the circuit connection material is applied to the first circuit member. It is preferable to irradiate with light after temporarily connecting and peeling off the support from the film-like circuit connecting material 10 if any. At this time, when the circuit member is transparent, the light irradiation can be performed through the circuit member.

  Furthermore, in the example of the connection method of the circuit member, the film-like circuit connection material 10 is temporarily connected to the first circuit member 20 once. However, the first circuit member 20 and the first circuit member 20 are not temporarily connected. The two circuit members 30 or 40 may be directly connected through the film-like circuit connecting material 10.

  In addition, the connection of TCP and FPC by the film-like circuit connecting material 10 (or circuit connecting material) of the present invention is performed by heating and pressurizing, but energy other than heat, for example, ultrasonic waves, electromagnetic waves, etc. is applied as necessary. You may use together. Further, the film-like circuit connecting material 10 (or circuit connecting material) of the present invention may be used by being divided into two or more layers.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

(Examples 1 to 3, Comparative Example 1)
The components shown in Table 1 were blended in the amounts (parts by weight) shown in the same table, and these were dissolved in a toluene solvent to obtain a solution having a solid content of 40% by weight. In addition, as the various components shown in Table 1, the following were specifically used.
Phenoxy resin: YP-50, manufactured by Tohto Kasei Co., Ltd .;
Polyurethane resin: T-6075, manufactured by Dainippon Ink, Inc.
Thermosetting composition 1: 50 parts by weight of bisphenol A type epoxy resin (Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd., epoxy equivalent 184), Microcapsule type latent curing agent (Novacure 3941-HX, manufactured by Asahi Kasei) 50 Parts by weight;
Thermosetting composition 2: 30 parts by weight of a bisphenol A type epoxy resin (Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd., epoxy equivalent 184), 30 parts by weight of a naphthalene skeleton-containing epoxy resin, a microcapsule type latent curing agent (Novacure 3941-HX, manufactured by Asahi Kasei Corporation) 40 parts by weight;
Thermosetting composition 3: 45 parts by weight of dicyclopentadiene diacrylate, 50 parts by weight of isocyanuric acid ethylene oxide-modified diacrylate, 5 parts by weight of dicumyl peroxide; Photocurable composition 1: Epoxy acrylate oligomer (NK oligo EA -1020, Shin-Nakamura Chemical Co., Ltd.) 30 parts by weight, acrylate monomer (NK Ester A-TMM-3L, Shin-Nakamura Chemical Co., Ltd.) 60 parts by weight, bisimidazole type photoinitiator (2,2′- 5 parts by weight of bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2-biimidazole, manufactured by Kurokin Kasei Co., Ltd .;
Photocurable composition 2: Bisphenol A type epoxy resin (Epicoat 828, product name, Epoxy equivalent 184 manufactured by Yuka Shell Epoxy Co., Ltd.) 100 parts by weight, (4-morpholinobenzoyl) -1-benzyl-1-dimethylaminopropane (Irgacure 369, manufactured by Ciba Specialty Chemicals Co., Ltd.) 4 parts by weight.

  Conductive particles having an average particle diameter of 4 μm were provided in the obtained solution (a nickel layer having a thickness of 0.2 μm was provided on the surface of particles having polystyrene as a core, and a gold layer having a thickness of 0.04 μm was provided on the surface of the nickel layer. The conductive particles) were mixed and dispersed in an amount of 4 parts by volume with respect to 100 parts by volume of the solid content in the solution to prepare a circuit connection material-containing liquid. Next, this circuit connection material-containing liquid is applied to an 80 μm-thick PET film having a surface treated on one side using a coating apparatus and dried with hot air at 70 ° C. for 10 minutes to obtain a film-like circuit connection material having a thickness of 18 μm. Obtained.

(Measurement of fluidity)
About the circuit connection materials obtained in Examples 1 to 3 and Comparative Example 1, the flowability in the initial state (the state before heating and light irradiation) and the irradiation amount of ² J / cm ² using a high-pressure mercury lamp The fluidity after irradiation with ultraviolet rays and the reaction rate of the circuit connecting material at that time were measured. The results are shown in Table 1.

(Production of circuit members)
On a polyimide film (thickness 40 μm), 500 copper circuits (thickness 8 μm) having a line width of 15 μm and a pitch of 30 μm were formed, and a flexible printed circuit board (FPC) as the second circuit member A was produced.

  In addition, a polyimide film with a copper foil having a three-layer structure in which a copper foil having a thickness of 18 μm was bonded to the polyimide film via an adhesive was prepared. The copper foil of this polyimide film with copper foil was patterned to a line width of 15 μm and a pitch of 30 μm and subjected to a resist treatment. Thereafter, the surface of the wiring and connection terminals formed from copper foil is Sn-plated, mounted with a chip, sealed with a resin at a temperature of 200 ° C., and a tape carrier package (TCP) as the second circuit member B Was made.

  Further, 500 indium-tin oxide (ITO) circuits (thickness: 200 nm) having a line width of 15 μm and a pitch of 30 μm were formed on a glass substrate (thickness: 1.1 mm) to produce a first circuit member.

(Circuit member connection 1)
First, the adhesive surfaces of the film-like circuit connecting materials (width 1.5 mm) of Examples 1 to 3 and Comparative Example 1 were attached on the first circuit member, and then heated at 80 ° C. and 1 MPa for 5 seconds. The film-like circuit connecting material was temporarily connected to the first circuit member by applying pressure. Next, the PET film is peeled off, and a film-like circuit connecting material is interposed between the second circuit member A (FPC) and the first circuit member, and the circuit electrode of the second circuit member A and the first circuit The 2nd circuit member A was arrange | positioned so that the circuit electrode of a member might oppose. Then, the film-like circuit connecting material was heated and pressurized at 150 ° C. and 4 MPa for 20 seconds via the second circuit member A and the first circuit member to form a circuit member connection structure.

(Circuit member connection 2)
First, the adhesive surfaces of the film-like circuit connecting materials (width 1.5 mm) of Examples 1 to 3 and Comparative Example 1 were attached on the first circuit member, and then heated at 80 ° C. and 1 MPa for 5 seconds. The film-like circuit connecting material was temporarily connected to the first circuit member by applying pressure. Next, the PET film was peeled off, and ultraviolet rays were irradiated on the entire surface of the film-like circuit connecting material using a high-pressure mercury lamp at an irradiation amount of ² J / cm ² . Thereafter, a film-like circuit connecting material is interposed between the second circuit member B (TCP) and the first circuit member, and the circuit electrode of the second circuit member B and the circuit electrode of the first circuit member are The second circuit member B was disposed so as to face each other. Then, the film-like circuit connection material was heated and pressurized at 150 ° C. and 4 MPa for 20 seconds via the second circuit member B and the first circuit member to form a circuit member connection structure.

(Evaluation of connection resistance)
About the connection structure of the said circuit member, the resistance value of the circuit was measured with the constant current of 1 mA using multimeter TR6848 (brand name, product made from Advantest Co., Ltd.). The measured resistance value was the sum (x + 3σ) of the average value x of 150 resistances between adjacent circuits and the value obtained by triple the standard deviation σ. The results are shown in Table 2.

(Evaluation of adhesive strength)
Regarding the connection structure of the circuit member, measure the peeling strength (90 ° peeling adhesive strength, conforming to JIS Z 0237) when peeling one circuit member in the direction of 90 degrees with respect to the other circuit member. Was used to measure the adhesive strength. The results are shown in Table 2.

(Evaluation of stability over time)
About the connection structure of the said circuit member, after performing the high temperature, high humidity test for 240 hours on 80 degreeC and 85% RH conditions, evaluation of the connection resistance was performed by the method similar to the above. The results are shown in Table 2.

  As is clear from the results shown in Table 2, according to the circuit connection materials of Examples 1 to 3, the second circuit member is either TCP or FPC, compared with the circuit connection material of Comparative Example 1. Thus, it was confirmed that the circuit members could be connected with sufficient adhesive strength and the connection resistance between the circuit electrodes could be sufficiently reduced. Moreover, according to the circuit connection material of Examples 1-3, by performing a high temperature, high humidity test about the connection structure of the circuit member using the circuit connection material of Examples 1-3 and the circuit connection material of Comparative Example 1, Compared to the circuit connection material of Comparative Example 1, it was confirmed that an increase in connection resistance over time can be sufficiently prevented.

  From the above, according to the circuit connection method of the present invention, even if one of the two circuit members to be connected is either TCP or FPC, the circuit members can be connected with sufficient adhesive strength, and the connection resistance between the circuit electrodes It was confirmed that the resistance can be sufficiently reduced and the increase in connection resistance over time can be sufficiently prevented.

  DESCRIPTION OF SYMBOLS 10 ... Film-like circuit connection material, 11 ... Adhesive composition, 12 ... Conductive particle, 20 ... First circuit member, 21 ... Circuit board (first circuit board), 22 ... Circuit electrode (first circuit) Electrode), 30 ... second circuit member (FPC), 31 ... circuit board (second circuit board), 32 ... circuit electrode (second circuit electrode), 40 ... second circuit member (TCP), 41 ... Circuit board (second circuit board), 42 ... Circuit electrode (second circuit electrode), 50 ... Light source.

Claims (5)

A first circuit member having a first circuit electrode; and a second circuit member having a second circuit electrode and constituting a tape carrier package or a flexible printed circuit board. A circuit connection method for connecting the first circuit member and the second circuit member using a circuit connection material for connecting the two circuit electrodes in a state of facing each other,
The circuit connection material contains a thermosetting composition and a photocurable composition that is cured by light irradiation, and can be connected to both the tape carrier package and the flexible printed board,
When the second circuit member constitutes the tape carrier package, the circuit connecting material having a thickness of 5 mm × 5 mm and a thickness of 35 μm is sandwiched between the glass members so as to be in the same thickness direction as the glass. ° C., in a case of performing 10 seconds heating and pressing under the conditions of 2 MPa, to the area S _a of the one to have contact with the surface of the glass at the initial of the circuit connecting material prior to the heat and pressure, said heat and pressure flowability represented by the ratio of the area S _b of the surface after the value of _(S b _/ S _a), by curing the photocurable composition by performing light irradiation to the circuit connecting material After setting to 1.3 to 3.0, the first circuit member and the second circuit member are connected by heating and pressing ,
When the second circuit member constitutes the flexible printed circuit board, the first circuit member and the second circuit member are heated and pressed without irradiating the circuit connecting material with light. The circuit connection method characterized by performing connection. When the overall response rate of the circuit connecting material after light irradiation is 5-50%, the flow represented by the ratio of the area S _b of the heating after pressurization to the initial area S _a of the circuit connecting material The circuit connection method according to claim 1, wherein the value of the property (S _b / S _a ) is 1.3 to 3.0.   The circuit connection method according to claim 1, wherein the thermosetting composition contains one of an epoxy resin and a radical polymerizable compound.   The said photocurable composition contains any one of a photo cation reactive compound, a photo radical reactive compound, and a photo anion reactive compound, It is any one of Claims 1-3 characterized by the above-mentioned. Circuit connection method.   The circuit connection method according to claim 1, wherein the circuit connection material further contains conductive particles.

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