TWI598890B - Hardening composition and connection structure - Google Patents

Description

Curable composition and joint structure

The present invention relates to a curable composition using a phenoxy resin and a bonded structure.

The curable composition containing a curable compound is widely used in various applications such as electric, electronic, construction, and vehicles.

As an example of the curable composition, Patent Document 1 below discloses (A) a phenoxy resin having a structure represented by the following formula (X), (B) an inorganic filler, and (C) A curable composition of a decane coupling agent. The content of the (C) decane coupling agent is 1% by mass or more and 10% by mass or less based on the total amount of the curable composition.

In the above formula (X), n and m are each independently an integer of 1 or more and 20 or less. R ¹ to R ¹⁹ are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen atom, and may be the same or different. X is a single bond, a hydrocarbon group having 1 to 20 carbon atoms, -O-, -S-, -SO ₂ - or -CO-.

Further, in order to electrically connect the various connection target members, conductive particles may be blended in the curable composition. The curable composition containing conductive particles is referred to as an anisotropic conductive material.

In order to obtain various connection structures, the anisotropic conductive material is used for, for example, a connection between a flexible printed substrate and a glass substrate (FOG (Film on Glass)), and a connection between a semiconductor wafer and a flexible printed substrate (COF (Chip on Film) , film-coated (), semiconductor wafer and glass substrate (COG (Chip on Glass)), and flexible printed circuit board and epoxy glass substrate (FOB (Film on Board)) .

As an example of the anisotropic conductive material, Patent Document 2 discloses a curing agent containing a free radical by heating, a hydroxyl group-containing resin having a molecular weight of 10,000 or more, a phosphate ester, a radical polymerizable substance, And an anisotropic conductive material (curable composition) of conductive particles. Specific examples of the hydroxyl group-containing resin include polymers such as polyvinyl butyral resin, polyvinyl formal, polyamine, polyester, phenol resin, epoxy resin, and phenoxy resin.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-23503

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2005-314696

When the prior curable composition described in Patent Documents 1 and 2 is used to connect the target member, the adhesion under high temperature and high humidity may be lowered.

An object of the present invention is to provide a curable composition which provides a cured product having high adhesion under high temperature and high humidity. Further, an object of the present invention is to provide a bonded structure using the above curable composition.

According to a broad aspect of the present invention, there is provided a curable composition comprising: a phenoxy resin having a hydrolyzable group in a side chain; and conductive particles.

In a specific aspect of the curable composition of the present invention, the hydrolyzable group is reactive with a hydroxyl group.

In a specific aspect of the curable composition of the present invention, the hydrolyzable group is an alkoxyalkyl group.

In a particular aspect of the curable composition of the present invention, the phenoxy resin is obtained by reacting a reactive functional group with a decane coupling agent and having no hydrolysis in the side chain. The phenoxy resin of the group is reacted with a decane coupling agent, and the hydrolyzable group derived from the above decane coupling agent is introduced into the side chain.

In a specific aspect of the curable composition of the present invention, the phenoxy resin has an epoxy group or a (meth) acrylonitrile group at the terminal.

In a specific aspect of the curable composition of the present invention, the curable composition contains a moisture hardening accelerator which promotes moisture hardening of the phenoxy resin.

In a specific aspect of the curable composition of the present invention, the moisture curing accelerator has a pH of 4 or less, and the moisture curing accelerator reacts with the hydrolyzable group in the phenoxy resin. Sex.

In a specific aspect of the curable composition of the present invention, the curable composition contains a radical polymerizable compound and a thermal radical polymerization initiator.

In a particular aspect of the curable composition of the present invention, the curable composition is used for the attachment of electronic components.

In a specific aspect of the curable composition of the present invention, the conductive particles are conductive particles having at least an outer surface of solder.

In a particular aspect of the curable composition of the present invention, the curable composition is a conductive material and is used for electrical connection between electrodes.

According to a broad aspect of the present invention, there is provided a connection structure comprising: a first connection target member having a first electrode on a surface; a second connection target member having a second electrode on its surface; and a connection between the first connection target member and a connection portion of the second connection target member, The connection portion is formed by curing the curable composition, and the first electrode and the second electrode are electrically connected by the conductive particles.

Since the phenoxy resin contained in the curable composition of the present invention has a hydrolyzable group in the side chain, the curable composition containing the phenoxy resin and the conductive particles can provide high adhesion under high temperature and high humidity. Hardened matter.

1‧‧‧Electrical particles

2‧‧‧Substrate particles

3‧‧‧ Conductive layer

3A‧‧‧2nd conductive layer

3B‧‧‧ solder layer

3Ba‧‧‧fused solder layer

11‧‧‧Electrical particles

12‧‧‧ solder layer

21‧‧‧Electrical particles

51‧‧‧Connection structure

52‧‧‧1st connection object component

52a‧‧‧1st electrode

53‧‧‧2nd connection object component

53a‧‧‧2nd electrode

54‧‧‧Connecting Department

Fig. 1 is a front cross-sectional view schematically showing a connection structure using a curable composition according to an embodiment of the present invention.

Fig. 2 is a front cross-sectional view schematically showing a portion where the conductive particles and the electrode in the connection structure shown in Fig. 1 are enlarged.

Fig. 3 is a cross-sectional view showing an example of conductive particles which can be used in the curable composition according to the embodiment of the present invention.

Fig. 4 is a cross-sectional view showing a variation of the conductive particles.

Fig. 5 is a cross-sectional view showing another modification of the conductive particles.

Hereinafter, the details of the present invention will be described.

(phenoxy resin)

The phenoxy resin (hereinafter sometimes referred to as phenoxy resin (A)) contained in the curable composition of the present invention has a hydrolyzable group in the side chain. Since the phenoxy resin has a hydrolyzable group, a curable composition which provides a cured product having high adhesion under high temperature and high humidity can be obtained by using the phenoxy resin (A). In particular, in the curable composition containing conductive particles, since the conductive particles are in contact with the target object, the adhesion tends to be lowered. Further, the connection structure using the curable composition containing conductive particles requires a very high level of adhesion under high temperature and high humidity. If the adhesion under high temperature and high humidity is high, a high conduction reliability can be obtained. In the present invention, the curability of the conductive particles is included The composition can effectively improve the adhesion under high temperature and high humidity.

In the present specification, the term "phenoxy resin" includes both a phenoxy resin obtained by a one-stage method and a phenoxy resin obtained by a multistage process. Specifically, examples of the phenoxy resin (A) include a polyhydroxy ether synthesized from a bisphenol and epichlorohydrin, or a polyhydroxy ether synthesized from an epoxy compound and a diol. Examples of the phenoxy resin (A) include a resin obtained by reacting epichlorohydrin with a dihydric phenol compound, and a resin obtained by reacting a binary epoxy compound with a dihydric phenol compound.

The hydrolyzable group is preferably reactive with a hydroxyl group from the viewpoint of effectively improving the adhesion under high temperature and high humidity. Specific examples of the hydrolyzable group include alkoxyalkylene group and alkoxy titanate group. The hydrolyzable group is preferably an alkoxyalkylene group from the viewpoint of effectively improving the adhesion under high temperature and high humidity.

The alkoxyalkylene group is preferably a group represented by the following formula (11).

-Si(OR1) _n R2 _m ...(11)

In the above formula (11), R1 and R2 each represent an alkyl group having 1 to 5 carbon atoms, n represents 2 or 3, m represents 0 or 1, and m+n represents 3. R1 and R2 are each preferably a methyl group or an ethyl group.

The phenoxy resin (A) preferably has an epoxy group or a (meth) acrylonitrile group at the terminal. In this case, high temperature and high humidity resistance can be exhibited by reacting the terminal functional groups with each other or by reacting the phenoxy resin (A) with a separately added reactive compound. The phenoxy resin (A) preferably has an epoxy group at the terminal, and preferably has a (meth) acrylonitrile group at the terminal.

The phenoxy resin (A) is preferably obtained by a phenoxy resin having a reactive functional group reactive with a decane coupling agent and having no hydrolyzable group in the side chain (hereinafter sometimes described) The phenoxy resin (a)) is reacted with a decane coupling agent, and a hydrolyzable group derived from the above decane coupling agent is introduced into a side chain.

Specific examples of the reactive functional group in the phenoxy resin (a) include an epoxy group and a hydroxyl group. The above reactive functional group is preferably a hydroxyl group.

Examples of the decane coupling agent include a decane coupling agent having an isocyanate group, a decane coupling agent having an epoxy group, and a decane coupling agent having an amine group. Among them, a decane coupling agent having an isocyanate group is preferred.

The phenoxy resin (A) has a weight average molecular weight of preferably 5,000 or more, more preferably 8,000 or more, preferably 150,000 or less, more preferably 50,000. Hereinafter, the number average molecular weight of the phenoxy resin (A) is preferably 2,000 or more, more preferably 3,000 or more, more preferably 50,000 or less, still more preferably 20,000 or less. When the weight average molecular weight is at least the above lower limit or less than the above upper limit, or the number average molecular weight is at least the above lower limit and not more than the above upper limit, it is further easy to have both rapid curing property and high bonding strength obtained by using the terminal functional group. The phenoxy resin (A) preferably has a skeleton derived from an aliphatic diol such as 1,6-hexanediol. Thereby, the peeling adhesion force can be further improved.

In the curable composition, the content of the phenoxy resin (A) is preferably 5% by weight or more, more preferably 10% by weight or more, and preferably 45% by weight, based on 100% by weight of the components other than the conductive particles. Hereinafter, it is more preferably 35% by weight or less. When the content of the phenoxy resin (A) is at least the above lower limit and not more than the above upper limit, the balance between moisture hardening and thermal hardening of the curable composition is further excellent.

(sclerosing composition)

The curable composition of the present invention comprises a phenoxy resin (A) having a hydrolyzable group in its side chain, and conductive particles. The curable composition of the present invention preferably comprises a phenoxy resin (A) having a hydrolyzable group in a side chain, and a moisture hardening accelerator which promotes moisture hardening of the phenoxy resin (A). The curable composition of the present invention is preferably hardenable by moisture. The curable composition of the present invention may also contain no such moisture hardening accelerator. The curable composition of the present invention may contain a curing agent or a polymerization initiator other than the above-described moisture curing accelerator, and may be added with the above-mentioned moisture curing accelerator at the time of use. The curable composition is a composition that is used for curing at the time of use. The above phenoxy resin (A) may be used alone or in combination of two. on. The conductive particles may be used alone or in combination of two or more. The above-mentioned moisture hardening accelerator may be used alone or in combination of two or more.

The moisture curing accelerator is not particularly limited as long as it can promote moisture curing of the phenoxy resin (A). It is preferable that the moisture hardening accelerator promotes moisture hardening of the phenoxy resin (A) by promoting hydrolysis of the phenoxy resin (A). In order to effectively perform moisture hardening, the moisture hardening accelerator is preferably reactive with the above hydrolyzable group in the phenoxy resin (A). Further, the moisture curing accelerator preferably has a polymerizable functional group. Examples of the polymerizable functional group include a (meth)acryl fluorenyl group and an epoxy group.

The pH of the moisture curing accelerator is preferably less than 7, more preferably 5 or less, still more preferably 4 or less, still more preferably 3 or less. When the pH of the moisture curing accelerator is not more than the above upper limit, the low-temperature curability of the curable composition can be further improved, and the radical reaction during storage of the curable composition (before thermal curing) can be suppressed. The storage stability of the above curable composition can be further improved. Further, when the pH of the pH adjusting agent is not more than the above upper limit, moisture curing of the curable composition can be promoted. The lower limit of the pH of the moisture curing accelerator is not particularly limited, and the pH of the moisture curing accelerator is preferably 1 or more, more preferably 2 or more. The above moisture hardening accelerator can also be used as a pH adjuster. The pH of the moisture curing accelerator is preferably lower than the pH of the radical polymerizable compound described below, more preferably lower than the pH of the radical polymerizable compound described below by 1 or more, and further preferably lower than The radical polymerizable compound has a pH of 3 or more.

The pH of the moisture-hardening accelerator may be 1 g of the moisture-hardening accelerator dissolved in 10 g of pure water, and then subjected to a pH meter ("D-72" manufactured by HORIBA, Inc.) and an electrode ToupH electrode 9615-10D. Determination.

The moisture hardening accelerator is preferably a phosphoric acid compound, and preferably has a (meth) acrylonitrile group.

Specific examples of the phosphoric acid compound include phosphoric acid (meth) acrylate, a phosphate compound, and a phosphite compound. From the viewpoint of effectively performing moisture curing, and rapidly thermally curing at a low temperature and further improving the storage stability of the curable composition, phosphoric acid (meth) acrylate is preferred. Examples of the moisture-hardening accelerator include "EBECRYL168" manufactured by Daicel-Allnex Co., Ltd., and "LIGHT ACRYLATE P-1A (N)" and "LIGHT ESTER P-1M" manufactured by Kyoeisha Chemical Co., Ltd., and " LIGHT ESTER P-2M" and so on.

The content of the moisture curing accelerator is preferably 0.1 part by weight or more, more preferably 1 part by weight or more, more preferably 15 parts by weight or less, and even more preferably 10 parts by weight based on 100 parts by weight of the phenoxy resin (A). Parts by weight or less. When the content of the moisture curing accelerator is not less than the above lower limit and not more than the above upper limit, the curable composition is effectively moisture-cured.

In addition, the content of the moisture curing accelerator is preferably 0.1 part by weight or more, more preferably 1 part by weight or more, more preferably 10 parts by weight or less, even more preferably 100 parts by weight of the radically polymerizable compound. 5 parts by weight or less. When the content of the moisture curing accelerator is not less than the above lower limit and not more than the above upper limit, the low-temperature curability and storage stability of the curable composition are further improved.

The above hard composition preferably contains a radical polymerizable compound and a thermal radical polymerization initiator. In this case, a hardenable composition which can be hardened by both moisture and heat is obtained. Moreover, by using a radically polymerizable compound and a thermal radical polymerization initiator, the adhesion of the curable composition under high temperature and high humidity can be further improved. The above-mentioned radically polymerizable compound may be used alone or in combination of two or more. The above-mentioned thermal radical polymerization initiator may be used alone or in combination of two or more.

Further, in the case of using the above radical polymerizable compound and the above-mentioned thermal radical polymerization initiator, the pH of the moisture curing accelerator is preferably less than 7, more preferably 5 or less, still more preferably 4 Hereinafter, it is more preferably 3 or less, and is preferably 2 or more. When the pH is at most the above upper limit, not only the moisture hardening of the curable composition but also the moisture hardening can be promoted. The low-temperature curability of the curable composition can be further improved, and the radical reaction during storage (before thermal curing) of the curable composition can be suppressed, and the storage stability of the curable composition can be further improved.

The radically polymerizable compound can be subjected to addition polymerization by a radical and has a radical polymerizable group. The radically polymerizable compound is a thermosetting compound.

The radical polymerizable group may, for example, be a group containing an unsaturated double bond. Specific examples of the radical polymerizable group include an allyl group, an isopropenyl group, a maleic acid group, a styryl group, a vinylbenzyl group, a (meth)acryl fluorenyl group, and a vinyl group. Further, the (meth)acryl fluorenyl group means an acryl fluorenyl group and a methacryl fluorenyl group.

In view of further improving the thermosetting property of the curable composition, the radical polymerizable group preferably has a vinyl group, more preferably a (meth) acrylonitrile group. In the case where the radical polymerizable group is a (meth) acrylonitrile group, the radical polymerizable group has a vinyl group.

Specific examples of the radical polymerizable compound include a compound having a (meth)acryl fluorenyl group, a compound having a vinyl group, and a compound having an allyl group. From the viewpoint of improving the crosslinking density of the cured product and further improving the adhesion of the cured product, a radically polymerizable compound having a (meth)acryl fluorenyl group is preferred.

The radically polymerizable compound preferably has a radical polymerizable group from the viewpoint of rapidly thermally curing at a low temperature and further improving the storage stability of the curable composition. a radically polymerizable compound of a phenyl group, preferably having a (meth) acrylonitrile group and A radically polymerizable compound of a phenyl group.

Above The phenyl group is a group represented by the following formula (1a).

The radical polymerizable compound is preferably a radical polymerizable compound represented by the following formula (1), from the viewpoint of the rapid thermal curing at a low temperature and further improving the storage stability of the curable composition.

In the above formula (1), R represents a hydrogen atom or a methyl group.

The pH of the radically polymerizable compound is preferably 9 or more, more preferably 10 or more, more preferably 13 or less, still more preferably 12 or less.

The pH of the radical polymerizable compound can be obtained by dissolving 1 g of the above radical polymerizable compound in 10 g of pure water, and then using a pH meter ("D-72" manufactured by HORIBA, Inc.) and an electrode ToupH electrode 9615-10D. Determination.

Further, the pH of the curable composition is preferably 5 or more, more preferably 6 or more, more preferably 9 or less, still more preferably less than 9, and still more preferably 8 or less. When the pH of the curable composition is not less than the above lower limit and not more than the above upper limit, the low-temperature curability and storage stability of the curable composition are further improved.

The pH of the curable composition was measured by dissolving 1 g of the curable composition in 10 g of pure water, and then using a pH meter ("D-72" manufactured by HORIBA) and an electrode ToupH electrode 9615-10D.

The content of the radically polymerizable compound is preferably 10 parts by weight or more, more preferably 30 parts by weight or more, more preferably 200 parts by weight or less, even more preferably 150% based on 100 parts by weight of the phenoxy resin (A). Parts by weight or less. When the content of the radically polymerizable compound is at least the above lower limit and not more than the above upper limit, the balance between moisture hardening and thermal hardening of the curable composition is further excellent.

Further, the above-mentioned radical polymerizable group and the above-mentioned phenoxy resin (A) are 100 parts by weight. The content of the radical polymerizable compound of the morphyl group and the content of the radical polymerizable compound represented by the above formula (1) are each preferably 20 parts by weight or more, more preferably 50 parts by weight or more, and still more preferably 300 parts by weight or less. More preferably, it is 200 parts by weight or less. When the content of the above-mentioned radically polymerizable compound is not less than the above lower limit and not more than the above upper limit, the low-temperature curability and storage stability of the curable composition are further improved.

The thermal radical polymerization initiator is not particularly limited, and examples thereof include an azo compound and an organic peroxide. The azo compound and the organic peroxide may be used alone or in combination of two or more.

Examples of the azo compound include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), and 2,2'-azobis (2,4). - dimethyl valeronitrile), 1,1'-azobis-1-cyclohexanecarbonitrile, dimethyl 2,2'-azobisisobutyrate, 2,2'-azobis(2- Methylpropionic acid) dimethyl ester, 1,1'-azobis(1-cyclohexanecarboxylic acid) dimethyl ester, 4,4'-azobis(4-cyanovaleric acid), 2,2 '-Azobis(2-amidinopropane) dihydrochloride, 2-tert-butylazo-2-cyanopropane, 2,2'-azobis(2-methylpropionamide) II Hydrate, and 2,2'-azobis(2,4,4-trimethylpentane) and the like.

The thermal radical polymerization initiator is preferably an organic peroxide from the viewpoint of rapid thermal hardening at a low temperature. Moreover, from the viewpoint of rapidly thermally curing at a low temperature and further improving the storage stability of the curable composition, the curable compound preferably contains a radical polymerizable group and The radical polymerizable compound of the morphyl group and the organic peroxide preferably further comprise a radical polymerizable compound represented by the above formula (1) and an organic peroxide.

Examples of the organic peroxide include a dithiol compound, a peroxyester compound, a hydrogen peroxide compound, a peroxydicarbonate compound, a peroxyketal compound, a dialkyl peroxide compound, and peroxidation. Ketone compounds and the like.

Examples of the above-mentioned dinonyl peroxide compound include benzammonium peroxide, diisobutylphosphonium peroxide, bis(3,5,5-trimethylhexyl peroxide), dilaurin peroxide, and Disuccinic acid peroxide or the like. Examples of the peroxyester compound include cumene peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, and third hexyl peroxy neodecanoate. Oxidized neodecanoic acid tert-butyl ester, peroxy neoheptanoic acid tert-butyl ester, peroxidic pivalic acid trihexyl ester, peroxy (2-ethylhexanoic acid) 1,1,3,3-tetramethyl Butyl ester, 2,5-dimethyl-2,5-di(2-ethylhexylperoxy)hexane, (2-ethylhexanoic acid) third hexyl ester, peroxidic pivalic acid Third butyl ester, (butyl 2-ethylhexanoate), third butyl peroxyisobutyrate, third butyl laurate, tert-butyl peroxy isophthalate, Tert-butyl acetate acetate, tert-butyl peroxyoctanoate and tert-butyl peroxybenzoate. Examples of the hydrogen peroxide compound include cumene hydroperoxide, hydroperoxide and menthane. Examples of the peroxydicarbonate compound include dibutyl peroxydicarbonate, di(4-tert-butylcyclohexyl)peroxydicarbonate, di-n-propylperoxydicarbonate, and peroxidation. Diisopropyl carbonate, di(2-ethylhexyl)peroxycarbonate, and the like. Further, as another example of the above-mentioned peroxide, methyl ethyl ketone peroxide, potassium persulfate, and 1,1-bis(t-butylperoxy)-3,3,5-trimethyl group are mentioned. Cyclohexane and the like.

The decomposition temperature for obtaining the 10-hour half-life of the above thermal radical polymerization initiator is preferably 30 ° C or higher, more preferably 40 ° C or higher, particularly preferably 90 ° C or lower, and particularly preferably 80 ° C or lower. When the decomposition temperature is 30 ° C or more, the storage stability of the curable composition is further improved. When the decomposition temperature is at most the above upper limit, the curable composition is effectively thermally cured.

The content of the thermal radical polymerization initiator is preferably 0.1 part by weight or more, more preferably 1 part by weight or more, even more preferably 10 parts by weight or less, and particularly preferably 5 parts by weight based on 100 parts by weight of the radically polymerizable compound. Parts by weight or less. When the content of the thermal radical polymerization initiator is not less than the above lower limit and not more than the above upper limit, the curable composition is effectively thermally cured.

Relative to the above, having a radical polymerizable group and 100 parts by weight of the radical polymerizable compound of the morphyl group and 100 parts by weight of the radically polymerizable compound represented by the above formula (1), the content of the organic peroxide is preferably 0.1 part by weight or more, more preferably 1 part by weight. The amount is preferably 10 parts by weight or less, more preferably 5 parts by weight or less. When the content of the organic peroxide is not less than the above lower limit and not more than the above upper limit, the low-temperature curability and storage stability of the curable composition are further improved.

From the viewpoint of further improving the adhesion of the cured product, the curable composition preferably contains a phenoxy resin selected from the group consisting of quinone imine (meth) acrylate and (meth) acrylonitrile. At least one selected from the group consisting of ester-modified epoxy (meth) acrylates and (meth) acrylate aliphatic urethanes, more preferably selected from the group consisting of quinone imine (meth) acrylates, At least one of a group consisting of a phenoxy resin having a (meth)acryl fluorenyl group and a caprolactone-modified epoxy (meth) acrylate. These are included in the radically polymerizable compound.

100% by weight of the curable composition, the quinone imine (meth) acrylate, the phenoxy resin having a (meth) acrylonitrile group, and the caprolactone-modified epoxy (meth) acrylate The total content is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, still more preferably 20 parts by weight or more, more preferably 80 parts by weight or less, still more preferably 60 parts by weight or less.

From the viewpoint of increasing the crosslinking density of the cured product and further improving the adhesion of the cured product, it is preferred to use a phenoxy resin having a (meth)acryl fluorenyl group and a caprolactone-modified epoxy (methyl). At least one of the acrylates. By using the above phenoxy resin having a (meth)acryl fluorenyl group and the above-mentioned caprolactone-modified epoxy (meth) acrylate, the adhesion of the cured product and the adhesion of the cured product under high temperature and high humidity are further improved. improve. The curable composition may include a phenoxy resin having a (meth) acrylonitrile group, and may also include a caprolactone-modified epoxy (meth) acrylate. The phenoxy resin having a (meth) acrylonitrile group and the caprolactone-modified epoxy (meth) acrylate may be used alone or in combination of two or more.

The content of the phenoxy resin having a (meth)acryl fluorenyl group is preferably 0 parts by weight or more, more preferably 10 parts by weight, based on 100 parts by weight of the phenoxy resin (A). The above is further preferably 50 parts by weight or more, preferably 200 parts by weight or less, more preferably 100 parts by weight or less. The content of the caprolactone-modified epoxy (meth) acrylate is preferably 0 parts by weight or more (not used) or more, more preferably 10 parts by weight or more, based on 100 parts by weight of the phenoxy resin (A). Further, it is preferably 50 parts by weight or more, preferably 200 parts by weight or less, more preferably 100 parts by weight or less. When the content of the phenoxy resin having a (meth)acryl fluorenyl group and the caprolactone-modified epoxy (meth) acrylate is at least the above lower limit and not more than the above upper limit, the cured material is cured and hardened. The adhesion of the substance under high temperature and high humidity is further improved.

The above hardened material is followed by the case of polyimine. The curable composition preferably contains a quinone imine (meth) acrylate from the viewpoint of further improving the adhesion to the polyimide. The above-mentioned quinone imine (meth) acrylate may be used alone or in combination of two or more.

The content of the above quinone imine (meth) acrylate is preferably 0 parts by weight or more, more preferably 10 parts by weight or more, even more preferably 100 parts by weight or more based on 100 parts by weight of the phenoxy resin (A). 50 parts by weight or more, preferably 200 parts by weight or less, more preferably 100 parts by weight or less. When the content of the quinone imine (meth) acrylate is not less than the above lower limit and not more than the above upper limit, the adhesion of the cured product and the adhesion under high temperature and high humidity of the cured product are further improved, in particular, the cured product is condensed. The adhesion of the amine is further improved.

The curable composition contains conductive particles. Examples of the conductive particles include conductive particles formed entirely of a conductive material, and conductive particles having a substrate particle and a conductive layer disposed on the surface of the substrate particle.

Further, the conductive particles are preferably conductive particles having at least an outer surface of solder. In this case, the adhesion between the connecting portion formed by curing the curable composition and the connecting member connected by the connecting portion is further improved by the solder.

As the conductive particles in which at least the outer surface is solder, solder particles or particles including the substrate particles and the solder layer disposed on the surface of the substrate particles can be used. its Among them, solder particles are preferably used. By using solder particles, high-speed transmission or metal bonding strength can be further improved.

Fig. 3 is a cross-sectional view showing an example of conductive particles which can be used in the curable composition according to the embodiment of the present invention. As shown in FIG. 3, the solder particles are preferably conductive particles 21 as solder particles. The conductive particles 21 are formed only of solder. The conductive particles 21 do not have substrate particles in the core, and are not core-shell particles. The central portion and the outer surface of the conductive particles 21 are each formed of solder.

From the viewpoint of further maintaining the connection distance between the members to be connected in a uniform manner, particles including the substrate particles and the solder layer disposed on the surface of the substrate particles may be used.

In the variation shown in FIG. 4, the conductive particles 1 include the substrate particles 2 and the conductive layer 3 disposed on the surface of the substrate particles 2. The conductive layer 3 covers the surface of the substrate particles 2. The conductive particles 1 are coated particles in which the surface of the substrate particles 2 is coated with the conductive layer 3.

The conductive layer 3 has a second conductive layer 3A and a solder layer 3B (first conductive layer) disposed on the surface of the second conductive layer 3A. The conductive particles 1 include the second conductive layer 3A between the substrate particles 2 and the solder layer 3B. Therefore, the conductive particles 1 include the substrate particles 2, the second conductive layer 3A disposed on the surface of the substrate particles 2, and the solder layer 3B disposed on the surface of the second conductive layer 3A. As described above, the conductive layer 3 may have a multilayer structure or a laminated structure of two or more layers.

As described above, the conductive layer 3 in the conductive particles 1 has a two-layer structure. As in another variation shown in FIG. 5, the conductive particles 11 may have the solder layer 12 as a single-layer conductive layer. The conductive particles 11 include substrate particles 2 and a solder layer 12 disposed on the surface of the substrate particles 2. The solder layer 12 may be disposed on the surface of the substrate particles 2 in such a manner as to be in contact with the substrate particles 2.

Among the conductive particles 1, 11, and 21, the conductive particles 1 and 11 are more preferable in terms of the thermal conductivity of the conductive material being further easily lowered. By using substrate particles, and The conductive particles of the solder layer disposed on the surface of the substrate particles further reduce the thermal conductivity of the conductive material.

Examples of the substrate particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, and metal particles. From the viewpoint of further efficiently disposing the conductive particles on the electrode, the substrate particles are preferably substrate particles other than metal, preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrids. particle. The substrate particles may also be copper particles.

The substrate particles are preferably resin particles formed of a resin. When the conductive particles are used to connect the electrodes, the conductive particles are compressed by placing the conductive particles between the electrodes and then compressing the conductive particles. When the base material particles are resin particles, the conductive particles are easily deformed at the time of the pressure bonding, and the contact area between the conductive particles and the electrode is increased. Therefore, the conduction reliability between the electrodes is further improved.

As the resin for forming the above resin particles, various organic materials can be preferably used. Examples of the resin for forming the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; and polymethacrylic acid; Acrylic resin such as methyl ester or polymethyl acrylate; polyalkylene terephthalate, polycarbonate, polyamine, phenol formaldehyde resin, melamine formaldehyde resin, benzoquinone Formaldehyde resin, urea formaldehyde resin, phenol resin, melamine resin, benzoquinone Resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polyfluorene, polyphenylene ether, polyacetal, polyimide, polyamidoxime Amine, polyetheretherketone, polyether oxime, divinylbenzene polymer, and divinylbenzene copolymer. Examples of the divinylbenzene-based copolymer and the like include a divinylbenzene-styrene copolymer and a divinylbenzene-(meth)acrylate copolymer. In order to easily control the hardness of the resin particles to a preferred range, the resin for forming the resin particles is preferably one obtained by polymerizing one or two or more kinds of polymerizable monomers having an ethylenically unsaturated group. The polymer.

To obtain the above resin particles by polymerizing a monomer having an ethylenically unsaturated group In the case of the monomer, the monomer having an ethylenically unsaturated group may be a non-crosslinkable monomer and a crosslinkable monomer.

Examples of the non-crosslinkable monomer include styrene monomers such as styrene and α-methylstyrene; and carboxyl groups such as (meth)acrylic acid, maleic acid, and maleic anhydride. Monomer; methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (methyl) ) lauryl acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylate Alkyl (meth) acrylate such as ester; 2-hydroxyethyl (meth) acrylate, glyceryl (meth) acrylate, polyoxyethylene (meth) acrylate, glycidyl (meth) acrylate, etc. a (meth) acrylate containing an oxygen atom; a nitrile-containing monomer such as (meth)acrylonitrile; a vinyl ether such as methyl vinyl ether, ethyl vinyl ether or propyl vinyl ether; vinyl acetate or butyric acid Vinyl esters such as vinyl ester, vinyl laurate, vinyl stearate; unsaturated hydrocarbons such as ethylene, propylene, isoprene, butadiene; trifluoromethyl (meth)acrylate, (methyl) A halogen-containing monomer such as pentafluoroethyl acrylate, vinyl chloride, vinyl fluoride or chlorostyrene.

Examples of the crosslinkable monomer include tetramethylolmethanetetra(meth)acrylate, tetramethylolmethanetri(meth)acrylate, and tetramethylolmethanedi(meth)acrylate. , trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, tris (meth) acrylate, di(meth) acrylate glycerol Ester, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)butanediol di(meth)acrylate, 1,4-butanediol II Polyfunctional (meth) acrylates such as (meth) acrylate; triallyl (iso) cyanurate, triallyl trimellitate, divinyl benzene, diallyl phthalate, and a monomer containing decane such as allyl acrylamide, diallyl ether, γ-(meth) propylene methoxy propyl trimethoxy decane, trimethoxy decyl styrene, vinyl trimethoxy decane, etc. .

The substrate particles are inorganic particles or organic-inorganic hybrid particles other than metals. In the case of the inorganic material for forming the substrate particles, cerium oxide, carbon black, or the like is exemplified. The above inorganic substance is preferably not a metal. The particles formed of the cerium oxide are not particularly limited, and examples thereof include particles obtained by hydrolyzing a hydrazine compound having two or more hydrolyzable alkoxyalkyl groups to form crosslinked polymer particles. Thereafter, baking is performed as needed. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of a crosslinked alkoxyfluorene alkyl polymer and an acrylic resin.

In the case where the substrate particles are metal particles, examples of the metal for forming the metal particles include silver, copper, nickel, rhodium, gold, and titanium. In the case where the substrate particles are metal particles, the metal particles are preferably copper particles. However, the above substrate particles are preferably not metal particles.

The melting point of the substrate particles is preferably higher than the melting point of the solder layer. The melting point of the substrate particles is preferably more than 160 ° C, more preferably more than 300 ° C, still more preferably more than 400 ° C, and even more preferably more than 450 ° C. Further, the substrate particles may have a melting point of less than 400 °C. The base material particles may have a melting point of 160 ° C or lower. The softening point of the substrate particles is preferably 260 ° C or higher. The softening point of the above substrate particles may also be less than 260 °C.

The conductive particles may have a single layer of solder layer. The conductive particles may have a plurality of conductive layers (solder layer, second conductive layer). In other words, the conductive particles may have two or more conductive layers laminated. Optionally, the solder particles may also be particles formed by a plurality of layers.

The solder forming the solder layer and the solder forming the solder particles are preferably low melting metals having a melting point of 450 ° C or lower. The solder layer is preferably a low melting point metal layer having a melting point of 450 ° C or less. The low melting point metal layer is a layer containing a low melting point metal. The solder particles are preferably low melting point metal particles having a melting point of 450 ° C or lower. The low melting point metal particles are particles containing a low melting point metal. The low melting point metal is a metal having a melting point of 450 ° C or lower. The melting point of the low melting point metal is preferably 300 ° C or lower, more preferably 160 ° C or lower. Further, it is preferable that the solder layer and the solder particles contain tin. 100% by weight of the metal contained in the solder layer, and 100% by weight of the metal contained in the solder particles The content of tin is preferably 30% by weight or more, more preferably 40% by weight or more, still more preferably 70% by weight or more, and particularly preferably 90% by weight or more. When the content of tin in the solder layer and the solder particles is at least the above lower limit, the connection reliability between the conductive particles and the electrode is further improved.

In addition, the content of the above-mentioned tin can be obtained by using a high-frequency inductively coupled plasma emission spectrometer ("ICP-AES" manufactured by Horiba, Ltd.) or a fluorescent X-ray analyzer ("EDX-800HS" manufactured by Shimadzu Corporation). ), etc. are measured.

By using the above-described solder particles and conductive particles having solder on the conductive surface, the solder is melted and bonded to the electrodes, and the solder is turned on between the electrodes. For example, the solder is easily in surface contact with the electrode rather than in point contact, and thus the connection resistance is lowered. Moreover, by using the conductive particles having solder on the conductive surface, the bonding strength between the solder and the electrode is increased, and as a result, peeling of the solder and the electrode is less likely to occur, and the conduction reliability and the connection reliability are effectively improved.

The low melting point metal constituting the solder layer and the solder particles is not particularly limited. The low melting point metal is preferably tin or an alloy containing tin. Examples of the alloy include a tin-silver alloy, a tin-copper alloy, a tin-silver-copper alloy, a tin-bismuth alloy, a tin-zinc alloy, and a tin-indium alloy. Among them, the low melting point metal is preferably tin, tin-silver alloy, tin-silver-copper alloy, tin-bismuth alloy, or tin-indium alloy in terms of excellent wettability of the electrode. More preferably, it is a tin-bismuth alloy or a tin-indium alloy.

The material constituting the solder (solder layer and the solder particles) is preferably a melt filler having a liquidus of 450 ° C or less based on JIS Z3001: welding term. Examples of the composition of the solder include a metal composition containing zinc, gold, silver, lead, copper, tin, antimony, indium, or the like. Among them, a tin-indium-based (117 ° C eutectic) or a tin-lanthanide (139 ° C eutectic) having a low melting point and no lead is preferable. That is, the solder preferably contains no lead, and is preferably a solder containing tin and indium or a solder containing tin and antimony.

In order to further improve the bonding strength between the solder and the electrode, the solder layer and the solder particles may further comprise nickel, copper, bismuth, aluminum, zinc, iron, gold, titanium, phosphorus, antimony, Metals such as ruthenium, cobalt, ruthenium, manganese, chromium, molybdenum and palladium. Further, from the viewpoint of further improving the bonding strength between the solder and the electrode, the solder layer and the solder particles preferably contain nickel, copper, ruthenium, aluminum or zinc. From the viewpoint of further increasing the bonding strength between the solder layer or the solder particles and the electrode, the content of the metals for improving the bonding strength is 100% by weight of the solder (100% by weight of the solder layer or 100% by weight of the solder particles) Preferably, it is 0.0001% by weight or more, preferably 1% by weight or less.

The melting point of the second conductive layer is preferably higher than the melting point of the solder layer. The melting point of the second conductive layer is preferably more than 160 ° C, more preferably more than 300 ° C, still more preferably more than 400 ° C, more preferably more than 450 ° C, more preferably more than 500 ° C, and most preferably more than 600 ° C . The solder layer has a low melting point and thus melts when electrically connected. Preferably, the second conductive layer is not melted when electrically connected. The conductive particles are preferably used by melting solder, and it is preferable to use the solder layer by melting, and it is preferable to use the solder layer without melting the second conductive layer. By making the melting point of the second conductive layer higher than the melting point of the solder layer, the solder layer can be melted without melting the second conductive layer during conductive connection.

The absolute value of the difference between the melting point of the solder layer and the melting point of the second conductive layer is preferably more than 0 ° C, more preferably 5 ° C or more, still more preferably 10 ° C or more, and still more preferably 30 ° C or more. It is 50 ° C or more, preferably 100 ° C or more.

The second conductive layer preferably contains a metal. The metal constituting the second conductive layer is not particularly limited. Examples of the metal include gold, silver, copper, platinum, palladium, zinc, lead, aluminum, cobalt, indium, nickel, chromium, titanium, ruthenium, osmium, iridium, tungsten, molybdenum, and cadmium, and the like. Alloys, etc. Further, as the metal, tin-doped indium oxide (ITO) can also be used. These metals may be used alone or in combination of two or more.

The second conductive layer is preferably a nickel layer, a palladium layer, a copper layer or a gold layer, more preferably a nickel layer or a gold layer, and further preferably a copper layer. The conductive particles preferably have a nickel layer, a palladium layer, a copper layer or a gold layer, more preferably have a nickel layer or a gold layer, and further preferably have a copper layer. By having this The conductive particles of the preferred conductive layer are used for the connection between the electrodes, and the connection resistance between the electrodes is further lowered. Further, a solder layer can be further easily formed on the surface of the preferred conductive layers.

The average particle diameter of the conductive particles is preferably 0.1 μm or more, more preferably 1 μm or more, more preferably 100 μm or less, still more preferably 80 μm or less, still more preferably 50 μm or less, and still more preferably 40 μm or less. When the average particle diameter of the conductive particles is not less than the above lower limit and not more than the above upper limit, the contact area between the conductive particles and the electrode is sufficiently increased, and the conductive particles are less likely to form when the conductive layer is formed. Moreover, it is suitable for the size of the conductive particles in the conductive material, and the interval between the electrodes connected via the conductive particles does not become excessively large, and the conductive layer is less likely to be peeled off from the surface of the substrate particles.

The particle diameter of the above conductive particles means a number average particle diameter. The average particle diameter of the above-mentioned conductive particles is determined by observing an arbitrary 50 conductive particles by an electron microscope or an optical microscope and calculating an average value.

The thickness of the solder layer is preferably 0.005 μm or more, more preferably 0.01 μm or more, more preferably 10 μm or less, still more preferably 1 μm or less, still more preferably 0.3 μm or less. When the thickness of the solder layer is not less than the above lower limit and not more than the above upper limit, sufficient conductivity can be obtained, and the conductive particles are not excessively hard, and the conductive particles are sufficiently deformed when the electrodes are connected. Further, the thinner the thickness of the solder layer, the easier it is to lower the thermal conductivity of the conductive material. The thickness of the solder layer is preferably 4 μm or less, and more preferably 2 μm or less, from the viewpoint of sufficiently lowering the thermal conductivity of the conductive material.

The thickness of the second conductive layer is preferably 0.005 μm or more, more preferably 0.01 μm or more, more preferably 10 μm or less, still more preferably 1 μm or less, still more preferably 0.3 μm or less. When the thickness of the second conductive layer is not less than the above lower limit and not more than the above upper limit, the connection resistance between the electrodes is further lowered. Further, the thinner the thickness of the second conductive layer, the easier it is to lower the thermal conductivity of the conductive material. The thickness of the second conductive layer is preferably 3 μm or less, and more preferably 1 μm or less, from the viewpoint of sufficiently lowering the thermal conductivity of the conductive material.

In the case where the conductive particles have only a solder layer as a conductive layer, the thickness of the solder layer is preferably 10 μm or less, and more preferably 5 μm or less. When the conductive particles have a solder layer and another conductive layer (such as a second conductive layer) different from the solder layer, the total thickness of the solder layer and the other conductive layers different from the solder layer is preferably 10 μm or less. More preferably, it is 5 μm or less.

The curable composition preferably contains the above-mentioned conductive particles and is a conductive material. The above conductive material is preferably an anisotropic conductive material. The above conductive material can be preferably used for electrical connection of electrodes. The above conductive material is preferably a conductive material for circuit connection.

In the case where the curable composition is a conductive material, the conductive material may be used in the form of a conductive paste, a conductive film or the like. When the conductive material is a conductive film, a film containing no conductive particles may be laminated on the conductive film containing the conductive particles.

The content of the conductive particles in 100% by weight of the curable composition is preferably 0.1% by weight or more, more preferably 1% by weight or more, further preferably 2% by weight or more, and still more preferably 10% by weight or more. More preferably, it is 20% by weight or more, more preferably 25% by weight or more, most preferably 30% by weight or more, preferably 80% by weight or less, more preferably 60% by weight or less, still more preferably 50% by weight or less. It is particularly preferably 45% by weight or less, and most preferably 35% by weight or less. When the content of the conductive particles is not less than the above lower limit and not more than the above upper limit, a large amount of conductive particles are easily disposed between the electrodes, and the conduction reliability is further improved. Further, since the content of the curable compound or the like is moderate, the conduction reliability between the electrodes is further improved.

The above curable composition preferably contains a flux. The flux is not particularly limited. As the flux, a flux which is usually used for soldering or the like can be used. Examples of the flux include zinc chloride, a mixture of zinc chloride and an inorganic halide, a mixture of zinc chloride and an inorganic acid, a molten salt, a phosphoric acid, a derivative of phosphoric acid, an organic halide, an anthracene, an organic acid, and Rosin and so on. The flux may be used alone or in combination of two or more.

Examples of the molten salt include ammonium chloride and the like. As the above organic acid, for example, Lactic acid, citric acid, stearic acid, glutamic acid, and glutaric acid. Examples of the rosin include activated rosin and non-activated rosin. The flux is preferably an organic acid or rosin having two or more carboxyl groups. The flux may be an organic acid having two or more carboxyl groups or a rosin. By using an organic acid or rosin having two or more carboxyl groups, the conduction reliability between the electrodes is further improved.

The above rosin is a rosin mainly composed of rosin acid. The flux is preferably rosin, more preferably rosin acid. By using the preferred flux, the conduction reliability between the electrodes is further improved.

The flux may be dispersed in the curable composition or may be attached to the surface of the conductive particles or the solder particles.

The content of the flux in 100% by weight of the curable composition is 0% by weight or less, preferably 0.5% by weight or more, preferably 30% by weight or less, more preferably 25% by weight or less. The above curable composition may also be free of flux. When the content of the flux is not less than the above lower limit and not more than the above upper limit, it is further difficult to form an oxide film on the surface of the solder and the electrode, and further, the oxide film formed on the surface of the solder and the electrode can be more effectively removed.

The curable composition may also contain, for example, a filler, a bulking agent, a softener, a plasticizer, a polymerization catalyst, a hardening catalyst, a colorant, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, and the like. Various additives such as lubricants, antistatic agents and flame retardants.

(connection structure)

The connection structure can be obtained by connecting the connection target members using the above-described curable composition.

The connection structure includes a first connection target member, a second connection target member, and a connection portion that connects the first connection target member and the second connection target member, and the connection portion is formed by curing the curable composition. form.

Fig. 1 is a front cross-sectional view schematically showing a connection structure using a curable composition according to an embodiment of the present invention. The curable composition used herein contains conductive particles 1. In addition to the conductive particles 1, conductive particles 11 or conductive particles 21 may be used. Further, conductive particles other than the conductive particles 1, 11, and 21 can also be used.

The connection structure 51 shown in FIG. 1 includes a first connection object member 52, a second connection object member 53, and a connection portion 54 that connects the first connection object member 52 and the second connection object member 53.

The first connection target member 52 has a plurality of first electrodes 52a on the front surface (upper surface). The second connection target member 53 has a plurality of second electrodes 53a on the front surface (lower surface). The first electrode 52a and the second electrode 53a are electrically connected by one or a plurality of conductive particles 1. Therefore, the first and second connection member members 52 and 53 are electrically connected by the conductive particles 1.

2 is a front cross-sectional view showing a portion where the conductive particles 1 and the first and second electrodes 52a and 53a in the connection structure 51 shown in FIG. 1 are connected. As shown in FIG. 2, in the connection structure 51, after the solder layer 3B in the conductive particles 1 is melted, the molten solder layer portion 3Ba is in sufficient contact with the first and second electrodes 52a and 53a. In other words, by using the conductive particles 1 whose surface layer is the solder layer 3B, the conductive particles 1 and the first and the first are compared with the case where the conductive layer of the conductive layer is made of a metal such as nickel, gold or copper. The contact area between the two electrodes 52a and 53a becomes large. Therefore, the conduction reliability and the connection reliability of the connection structure 51 can be improved. Further, in the case of using a flux, the flux is usually gradually deactivated by heating. Moreover, from the viewpoint of further improving the conduction reliability, it is preferable that the second conductive layer 3A is in contact with the first electrode 52a, and it is preferable that the second conductive layer 3A is in contact with the second electrode 53a.

The method for producing the above-described connection structure is not particularly limited. An example of the method for producing the connection structure is to arrange the curable composition between the first connection member and the second connection member to obtain a laminate, and then heat and press the laminate. Method, etc. The pressure of the above pressurization is about 9.8 × 10 ⁴ to 4.9 × 10 ⁶ Pa. The heating temperature is about 120 to 220 °C.

The first and second connection target members are not particularly limited. Specific examples of the first and second connection target members include electronic components such as semiconductor wafers, capacitors, and diodes, and electronic components such as printed circuit boards, flexible printed circuit boards, and epoxy glass substrates and glass substrates. Parts, etc. The above curable composition is preferably a conductive material for the connection of electronic parts. The curable composition is preferably a liquid material and is applied to a conductive material on the upper surface of the member to be joined in a liquid state. The above curable composition is preferably used for electrical connection between electrodes.

Examples of the electrode provided in the connection target member include metal electrodes such as a gold electrode, a nickel electrode, a tin electrode, an aluminum electrode, a copper electrode, a silver electrode, a molybdenum electrode, and a tungsten electrode. In the case where the connection target member is a flexible printed circuit board, the electrode is preferably a gold electrode, a nickel electrode, a tin electrode or a copper electrode. In the case where the connection target member is a glass substrate, the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode or a tungsten electrode. Further, in the case where the electrode is an aluminum electrode, it may be an electrode formed only of aluminum, or an electrode having an aluminum layer on the surface layer of the metal oxide layer. Examples of the material of the metal oxide layer include indium oxide doped with a trivalent metal element and zinc oxide doped with a trivalent metal element. Examples of the trivalent metal element include Sn, Al, Ga, and the like.

Hereinafter, the present invention will be specifically described by way of examples and comparative examples. The invention is not limited to the following examples.

(phenoxy resin (A))

The following phenoxy resins (A1), (A2), and (A3) were synthesized.

(Synthesis Example 1)

(1) Synthesis of the first reactant of bisphenol F with 1,6-hexanediol diglycidyl ether and bisphenol F-type epoxy resin:

72 parts by weight of bisphenol F (containing 4,4'-methylene bisphenol, 2,4'-methylene bisphenol and 2,2'-methylene bisphenol in a weight ratio of 2:3:1) 70 parts by weight of 1,6-hexanediol diglycidyl ether, and bisphenol F type epoxy resin ("EPICLON EXA-830CRP" manufactured by DIC Corporation) 30 weight The mixture was added to a three-necked flask and dissolved at 150 ° C under a nitrogen gas stream. Thereafter, 0.1 part by weight of tetra-n-butyl bromide as an addition reaction catalyst of a hydroxyl group and an epoxy group was added, and an addition polymerization reaction was carried out at 150 ° C for 6 hours under a nitrogen stream to obtain a first reaction. Things.

It was confirmed by NMR (Nuclear Magnetic Resonance) that the addition reaction was carried out, and it was confirmed that the first reactant had a hydroxyl group derived from bisphenol F and 1,6-hexanediol diglycidyl ether and bisphenol in the main chain. A structural unit in which an epoxy group of an F-type epoxy resin is bonded and has an epoxy group at both ends.

172 parts by weight of the above first reactant was placed in a three-necked flask, and dissolved at 150 ° C under a nitrogen gas stream. Thereafter, 4 parts by weight of acrylic acid and 0.1 part by weight of bromobutyltriphenylphosphonium bromide as a reaction catalyst for the carboxyl group of the acrylic acid and the terminal epoxy group of the first reactant were added, and the mixture was allowed to flow at 150 ° C under a nitrogen gas stream. The reaction was carried out for 8 hours. Thereafter, it was vacuum dried at 130 ° C for 5 hours to remove unreacted acrylic acid. Thereby, the second reactant was obtained.

It was confirmed by NMR that the reaction between the acrylic acid group and the epoxy group at both terminals of the first reactant was confirmed, and it was confirmed that the obtained compound had a hydroxyl group derived from bisphenol F and 1,6-hexanediol divergence in the main chain. Structural list of ethoxylated bonds of glycerol ether and bisphenol F epoxy resin The epoxy group at both ends is reacted with a carboxyl group of acrylic acid to have an acryl group at both ends.

The second reactant obtained by GPC (Gel Permeation Chromatography) had a weight average molecular weight of 15,000 and a number average molecular weight of 5,000.

100 parts by weight of the above second reactant was placed in a three-necked flask, and dissolved at 120 ° C under a nitrogen gas stream. Thereafter, 2 parts by weight of "KBE-9007" (3-isocyanatepropyltriethoxydecane) manufactured by Shin-Etsu Silicones Co., Ltd. was added, and a side chain hydroxyl group and a 3-isocyanatepropyl group as a second reactant were added. 0.002 parts by weight of dibutyltin dilaurate, which is an isocyanate group of triethoxydecane, was reacted at 120 ° C for 4 hours under a nitrogen stream. Thereafter, it was vacuum dried at 110 ° C for 5 hours to remove unreacted KBE-9007.

It was confirmed by NMR that the reaction of the side chain hydroxyl group of the second reactant with the isocyanate group of 3-isocyanatepropyltriethoxydecane confirmed that the obtained compound had a hydroxyl group derived from bisphenol F in the main chain and 1 a structural unit in which an epoxy group of 6-hexanediol diglycidyl ether and a bisphenol F-type epoxy resin is bonded, and has an acrylonitrile group at both ends and a C chain at the side chain. Triethoxy decyl group. Thereby, a phenoxy resin (A1) was obtained.

In the above formula, R represents a group represented by the following formula or a hydroxyl group.

The phenoxy resin (A1) obtained by GPC had a weight average molecular weight of 16,000 and a number average molecular weight of 5,500.

(Synthesis Example 2)

100 parts by weight of the above first reactant obtained in Synthesis Example 1 was placed in a three-necked flask, and dissolved at 120 ° C under a nitrogen gas stream. Thereafter, 2 parts by weight of "KBE-9007" (3-isocyanatepropyltriethoxydecane) manufactured by Shin-Etsu Silicones Co., Ltd. was added, and a side chain hydroxyl group and a 3-isocyanatepropyl group as the first reactant were added. 0.002 parts by weight of dibutyltin dilaurate, which is an isocyanate group of triethoxydecane, was reacted at 120 ° C for 4 hours under a nitrogen stream. Thereafter, it was vacuum dried at 110 ° C for 5 hours to remove unreacted KBE-9007.

The side chain hydroxyl group of the first reactant and the 3-isocyanatepropyl three were confirmed by NMR. The reaction of the isocyanate group of ethoxy decane confirmed that the obtained compound had an epoxy group derived from a hydroxyl group of bisphenol F and 1,6-hexanediol diglycidyl ether and a bisphenol F type epoxy resin in the main chain. A structural unit bonded to a group having an epoxy group at both ends and a propyltriethoxydecyl group in the side chain. Thereby, a phenoxy resin (A2) was obtained.

In the above formula, R represents a group represented by the following formula or a hydroxyl group.

(Synthesis Example 3)

100 parts by weight of the above first reactant obtained in Synthesis Example 1 was placed in a three-necked flask, and dissolved at 120 ° C under a nitrogen gas stream. Thereafter, 3 parts by weight of "KBE-403" (3-glycidoxypropyltriethoxydecane) manufactured by Shin-Etsu Silicones Co., Ltd. was added, and a side chain hydroxyl group and 3-glycidol as a first reactant were added. 0.1 part by weight of tetra-n-butylphosphonium bromide as a reaction catalyst of an epoxy group of oxypropyltriethoxydecane, and reacted at 120 ° C for 4 hours under a nitrogen gas stream. Thereafter, it was vacuum dried at 110 ° C for 5 hours. At the time, unreacted KBE-403 was removed.

It was confirmed by NMR that the reaction of the side chain hydroxyl group of the first reactant with the epoxy group of 3-glycidoxypropyltriethoxydecane confirmed that the obtained compound had a bisphenol F-derived group in the main chain. a structural unit in which a hydroxyl group is bonded to an epoxy group of 1,6-hexanediol diglycidyl ether and a bisphenol F-type epoxy resin, and has an epoxy group at both terminals and a propyl group of three in the side chain. Oxyalkylene. Thereby, a phenoxy resin (A3) was obtained.

Moreover, as a compounding component of a curable composition, the following materials were prepared.

(Phenoxy resin not meeting the phenoxy resin (A))

Other phenoxy resin ("YP-50S" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.)

(moisture hardening accelerator)

Phosphate acrylate ("EBECRYL168" manufactured by Daicel-Allnex, pH = 2.8)

Phosphate methacrylate: 2-methylpropenyloxyethyl acid phosphate ("LIGHT ESTER P-1M" manufactured by Kyoeisha Chemical Co., Ltd., pH = 3)

Phosphate acrylate 2: 2-propenyloxyethyl acid phosphate ("LIGHT ACRYLATE P-1A(N)", manufactured by Kyoeisha Chemical Co., Ltd., pH = 3)

(radical polymerizable compound)

Radical polymerizable compound 1 (acryloyl fluorenyl) Porphyrin, "ACMO" manufactured by KOHJIN Co., Ltd., pH = 11.5, a compound represented by the above formula (1), and R is a hydrogen atom)

(thermosetting compound)

Thermosetting compound (epoxy resin, "EPICLON EAX-4850-150" manufactured by DIC Corporation)

(thermal radical polymerization initiator)

Organic peroxide ("Perocta O" manufactured by Nippon Oil Corporation)

(hot hardener)

Thermal hardener ("HXA3922HP" manufactured by Asahi Kasei E-materials Co., Ltd., Microencapsulated amine-based hardener)

(conductive particles)

Solder particles ("DS-10" manufactured by Mitsui Metals Co., Ltd., average particle size 10 μm)

(other compounds)

(Meth)acrylic acid modified phenoxy resin (second reactant described above)

Caprolactone-modified epoxy (meth) acrylate 1 ("EBECRYL 3708" manufactured by Daicel-Allnex)

Acrylic aliphatic urethane ("EBECRYL8413" manufactured by Daicel-Allnex)

醯imino acrylate ("M-140" by East Asia Synthetic Co., Ltd.)

Decane coupling agent ("KBE-9007", 3-isocyanate propyl triethoxy decane, manufactured by Shin-Etsu Silicones Co., Ltd.)

(Examples 1 to 11 and Comparative Examples 1 to 3)

(1) Preparation of a curable composition

The components shown in the following Table 1 were blended in the amounts shown in Table 1 below, and the temperature of the paste was controlled to 30 ° C or less by a planetary mixer, and stirred at 2000 rpm for 10 minutes, thereby obtaining anisotropy. Conductive paste.

(2) Production of connection structure

An epoxy glass substrate (FR-4 substrate) having an electrode pattern (width: 3 mm, number of electrodes: 70) on which a copper electrode having an L/S of 100 μm/100 μm was plated with Ni/Au was prepared. Further, a soft printed substrate having a Ni/Au-plated electrode pattern (width: 3 mm, number of electrodes: 70) on a copper electrode having an L/S of 100 μm/100 μm was prepared.

The curable composition was applied to the upper surface of the epoxy glass substrate so as to have a thickness of 150 μm and a width of 0.8 mm to form a curable composition layer. Next, the flexible printed circuit board is layered on the surface layer of the curable composition layer so that the electrodes face each other.

Then, the temperature of the heating head was adjusted so that the temperature of the curable composition layer on the electrode was 140 ° C by the crimping machine ("BD-03" manufactured by Asahashi Kogyo Co., Ltd.), and 1.0 MPa was applied. The pressure is crimped for 10 seconds. Thereby, the solder is melted and the curable composition layer is cured to obtain a bonded structure.

(Evaluation)

(1) pH value

After dissolving 1 g of the curable composition in 10 g of pure water, the pH of the obtained curable composition was measured by a pH meter ("D-72" manufactured by HORIBA Co., Ltd.) and an electrode ToupH electrode 9615-10D.

(2) preservation stability

The initial viscosity of the curable composition was measured. Further, after the curable composition was allowed to stand at 23 ° C for 48 hours, the viscosity after standing for 48 hours was measured. The measurement of the viscosity was carried out by using an E-type viscometer TV-33 (manufactured by Toki Sangyo Co., Ltd.), and the storage stability of the curable composition was evaluated. The storage stability was determined on the basis of the following criteria.

[Criteria for the determination of preservation stability]

○○: Viscosity/initial viscosity after standing for 48 hours is less than 1.2 times

○: Viscosity/initial viscosity after standing for 48 hours is 1.2 times or more and less than 1.5 times

△: The viscosity/initial viscosity after standing for 48 hours is 1.5 times or more and less than 2 times

×: viscosity/initial viscosity is more than 2 times after standing for 48 hours

(3) low temperature hardening

The "DSC200" manufactured by the differential scanning calorimeter SII company was used, and 2 mg of the curable composition was taken, and the temperature was measured at a temperature increase rate of 10 ° C/min at 30 ° C to 300 ° C under a nitrogen gas flow to obtain an exothermic peak area A.

When the connection structure was produced, the temperature of the heating head was adjusted so that the temperature of the curable composition layer on the electrode was 130° C., 140° C., and 150° C., and the pressure was 1.0 MPa and the pressure was applied for 10 seconds. . Thereafter, by heating the connection structure to The flexible printed circuit board was peeled off at 180 ° C at 120 ° C to peel it off. 2 mg of the curable composition on the epoxy glass substrate was taken, and the exothermic peak area B was obtained by DSC. By "reaction rate (%) = (1 - (the exothermic peak area B of the curable composition heated to 130 ° C, 140 ° C or 150 ° C / the exothermic peak area A of the curable composition before heating) ) × 100" and evaluated low-temperature hardenability. The low temperature hardenability was judged by the following criteria.

[Criteria for determining low-temperature hardenability]

○○: The reaction rate at the time of pressure bonding at 130 ° C is 80% or more

○: The reaction rate when it is not in compliance with ○○ and is crimped at 140 ° C is 80% or more.

△: The reaction rate when not in compliance with ○○ and ○ and crimping at 150 ° C is 80% or more

×: does not meet ○○ and ○ and the reaction rate at 150 ° C is less than 80%

(4) Continuity

The connection resistance between the lower electrodes on the obtained connection structure was measured by a four-terminal method. Calculate the average of the two connection resistances. Furthermore, the connection resistance can be obtained by measuring the voltage at which a constant current flows in accordance with the relationship of voltage=current×resistance. The conductivity between the upper and lower electrodes was determined by the following criteria (the obtained resistance value was 3 mm × 100 μm in the electrode area and the total connection resistance between the lower electrodes × 70).

[Base of Judgment Benchmark]

○○: The average value of the connection resistance is 8.0 Ω or less.

○: The average value of the connection resistance exceeds 8.0 Ω and is 10.0 Ω or less.

△: The average value of the connection resistance exceeds 10.0 Ω and is 15.0 Ω or less.

×: The average value of the connection resistance exceeds 15.0 Ω

(5) Adhesion under high temperature and high humidity

Using the obtained connection structure, the "Micro Autograph MST-I" manufactured by Shimadzu Corporation was used to measure the 90° peel strength C at a tensile speed of 50 mm/min in a 23 ° C environment. After standing at 85 ° C and a humidity of 85% for 500 hours, the 90° peel strength D was measured in the same manner. The adhesion under high temperature and high humidity was determined on the basis of the following criteria.

[Criteria for judging the adhesion under high temperature and high humidity]

○○: 90° peel strength D is 20 N/cm or more, and D/C×100 is 80% or more.

○: 90° peel strength D is 15 N/cm or more and less than 20 N/cm, and D/C×100 is 80% or more.

△: 90° peel strength D is 10 N/cm or more and less than 15 N/cm, and D/C×100 is 80% or more.

×: 90° peel strength D is less than 10 N/cm

The composition and evaluation results of the curable composition are shown in Table 1 below.

Claims (9)

A curable composition comprising: a phenoxy resin having an alkoxyalkylalkyl group having a hydrolyzable group in a side chain; and a conductive particle, wherein the phenoxy resin is obtained by: a phenoxy resin in which an isocyanate group of an isocyanate group-containing decane coupling agent reacts with a reactive functional group and an alkoxyalkyl group having no hydrolyzable group in a side chain, reacts with an isocyanate group-containing decane coupling agent, and Alkoxyalkylene group derived from a hydrolyzable group of the above decane coupling agent is introduced into a side chain, or a reactive functional group having an epoxy group having an epoxy group-containing decane coupling agent is reacted on the side a phenoxy resin having an alkoxyalkylalkyl group having no hydrolyzable group, and reacting with an epoxy group-containing decane coupling agent, and introducing an alkoxyalkyl group derived from a hydrolyzable group of the above decane coupling agent to Side chain. The sclerosing composition according to claim 1, wherein the phenoxy resin having an alkoxyalkyl group having a hydrolyzable group in the side chain has an epoxy group or a (meth) acryl group at the terminal. The curable composition according to claim 1 or 2, which comprises a moisture hardening accelerator for promoting moisture hardening of a phenoxy resin having an alkoxyalkyl group having a hydrolyzable group in the side chain. The sclerosing composition according to claim 3, wherein the moisture hardening accelerator has a pH of 4 or less, and the moisture hardening accelerator and the above-mentioned phenoxy resin having a hydrolyzable alkoxyalkylene group in the side chain. The alkoxyalkylene group of the above hydrolyzable group is reactive. The curable composition according to claim 1 or 2, which comprises a radical polymerizable compound and a thermal radical polymerization initiator. A sclerosing composition according to claim 1 or 2, which is used for the connection of electronic parts. The sclerosing composition of claim 1 or 2, wherein the conductive particles are at least external The surface is a conductive particle of solder. A sclerosing composition according to claim 1 or 2 which is a conductive material and is used for electrical connection between electrodes. A connection structure including: a first connection target member having a first electrode on its surface; a second connection target member having a second electrode on its surface; and a connection portion connecting the first connection target member and the second connection target member The connection portion is formed by curing the curable composition according to any one of claims 1 to 8, and the first electrode and the second electrode are electrically connected by the conductive particles.