KR102490406B1 - Adhesive composition and bonded structure - Google Patents

Abstract

[식 (A) 중, R¹, R² 및 R³은 각각 독립적으로, 수소 원자, 탄소수 1 내지 18의 알킬기 또는 아릴기를 나타내고, R⁴, R⁵ 및 R⁶은 각각 독립적으로, 수소 원자 또는 특정한 유기기를 나타냄](a) a thermoplastic resin, (b) a radical polymerizable compound, (c) a radical polymerization initiator, and (d) a complex containing boron, and (d) a complex containing boron having the following general formula ( An adhesive composition, which is a compound represented by A).

[In Formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an aryl group, and R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom or represents a specific organic group]

Description

Adhesive composition and bonded structure

The present invention relates to an adhesive composition and a bonded structure.

BACKGROUND OF THE INVENTION In semiconductor devices and liquid crystal display devices, various adhesives have conventionally been used for the purpose of bonding various members in the device. Demands for adhesives span a wide range, such as adhesiveness, heat resistance, reliability in high temperature and high humidity conditions, and the like. The adhesive is used for connection between a liquid crystal display element and TCP (or COF), connection between FPC and TCP (or COF), connection between TCP (or COF) and printed wiring board, and connection between FPC and printed wiring board. In addition, the adhesive is also used when mounting a semiconductor element on a substrate.

Examples of adherends used for bonding include printed wiring boards, organic substrates such as polyimide resin, polyethylene terephthalate (PET), polycarbonate (PC), and polyethylene naphthalate (PEN), metals such as copper and aluminum, or ITO (composite oxide of indium and tin), IZO (composite oxide of indium and zinc), AZO (composite oxide of zinc and aluminum), SiN (silicon nitride), SiO ₂ (silicon dioxide), etc. substrate is used. Therefore, molecular design of the adhesive composition according to each adherend is required.

BACKGROUND ART [0002] In recent years, with the high integration of semiconductor elements or the high definition of liquid crystal display elements, the pitch between elements and the pitch between wires are being narrowed. In addition, a semiconductor element, a liquid crystal display element, or a touch panel using an organic substrate having low heat resistance such as PET, PC, or PEN is being used. When the heating temperature at the time of curing is high and the curing rate is slow in such an adhesive composition applied to a semiconductor device or the like, not only the desired connection portion but also the peripheral member is excessively heated, and damage to the peripheral member tends to be a factor. Therefore, adhesion by low-temperature curing is requested|required about adhesive composition.

Conventionally, a thermosetting resin using an epoxy resin, which exhibits high adhesiveness and high reliability, has been used as the adhesive for the semiconductor element or liquid crystal display element (see, for example, Patent Document 1 below). As constituent components of the resin, epoxy resins, curing agents (such as phenolic resins) having reactivity with the epoxy resin, and latent catalysts promoting the reaction between the epoxy resin and the curing agent are generally used. The heat latent catalyst is a material that does not react at storage temperatures such as room temperature and exhibits high reactivity when heated, and is an important factor in determining the curing temperature and curing speed, and the storage stability of the adhesive at room temperature and the time of heating. Various compounds have been used in terms of the cure rate of In the actual process, desired adhesion was obtained under curing conditions of curing at a temperature of 170 to 250°C for 1 to 3 hours. However, in order to cure the above adhesive at low temperature, it is necessary to use a latent catalyst having low activation energy, but it is very difficult to achieve both storage stability.

In recent years, radical curable adhesives using a radically polymerizable compound such as an acrylate derivative or a methacrylate derivative in combination with a peroxide as a radical polymerization initiator have attracted attention. In radical curing, since radicals, which are reactive active species, are highly reactive, curing in a short time is possible (for example, see Patent Document 2 below). In such a radical curable adhesive, a method of using benzoyl peroxide (BPO), an amine compound, an organic boron compound, or the like in combination as a radical polymerization initiator has been proposed (for example, see Patent Document 3 below).

Japanese Unexamined Patent Publication (Hei) 1-113480 International Publication No. 98/44067 Japanese Unexamined Patent Publication No. 2000-290121

In order to cure the above-mentioned radical curable adhesive at low temperature, it is necessary to use a radical polymerization initiator, but it is very difficult to achieve both low-temperature curability and storage stability in conventional radical curable adhesives. For example, when the aforementioned benzoyl peroxide (BPO), an amine compound, an organoboron compound, or the like is used as a radical polymerization initiator for a radical polymerizable compound such as an acrylate derivative or a methacrylate derivative, room temperature (25° C., Since the curing reaction proceeds also in the following), the storage stability may be lowered.

Then, an object of this invention is to provide the adhesive composition excellent in low-temperature curability and storage stability. Moreover, the present invention aims to provide a bonded structure using such an adhesive composition.

The inventors of the present invention, as a result of intensive studies to solve the above problems, found that excellent low-temperature curability and storage stability are obtained by using a specific complex containing boron as a constituent component of an adhesive composition, and to complete the present invention reached

That is, the adhesive composition according to the present invention contains (a) a thermoplastic resin, (b) a radically polymerizable compound, (c) a radical polymerization initiator, and (d) a complex containing boron, and (d) boron A complex containing is a compound represented by the following general formula (A).

[In Formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an aryl group, and R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, Representing an alkyl group having 1 to 18 carbon atoms, an organic group represented by the following general formula (a1), or an organic group represented by the following general formula (a2)]

[In Formula (a1), R ^7a represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ^7b represents a hydrogen atom, an amino group, an alkoxy group, or an alkyl group having 1 to 10 carbon atoms. In addition, s and t each independently represent an integer from 1 to 10]

[In Formula (a2), R ⁸ represents an alkyl group having 1 to 10 carbon atoms. In addition, u represents an integer from 1 to 10]

In the present invention, since the decomposition of the (c) radical polymerization initiator in low temperature (for example, 80 to 120 ° C.) can be promoted by the adhesive composition containing the complex containing (d) boron, the adhesive composition has excellent low-temperature curing properties. Further, in the present invention, the storage stability of the adhesive composition (for example, around room temperature (for example, -20 to 25 ° C.) ) is excellent, and even when the adhesive composition is stored for a long time, excellent adhesive strength and connection resistance (eg, bonding strength and connection resistance in the connection structure of circuit members or solar cell modules) You can get it. As described above, the adhesive composition according to the present invention is excellent in low-temperature curability and storage stability.

Further, in the present invention, excellent adhesive strength and connection resistance can be obtained regardless of whether or not the adhesive composition is stored for a long period of time. In addition, in the present invention, stable performance (adhesive strength and connection resistance) can be maintained even after a long-term reliability test (high temperature and high humidity test) regardless of whether or not the adhesive composition is stored for a long time.

In the adhesive composition according to the present invention, the (b) radically polymerizable compound may contain a vinyl compound having a phosphoric acid group and radically polymerizable compounds other than the vinyl compound. In this case, bonding by low-temperature curing becomes easy, and bonding strength with the board|substrate which has a connecting terminal can further be improved.

Further, (a) thermoplastic resins include phenoxy resins, polyurethane resins, polyesterurethane resins, butyral resins, (meth)acrylic resins, polyimide resins and polyamide resins, and copolymers having structural units derived from vinyl acetate. You may contain at least 1 sort(s) selected from the group which consists of coalescence. In this case, heat resistance and adhesiveness are further improved, and these excellent properties can be easily maintained even after a long-term reliability test (high temperature and high humidity test).

Moreover, the adhesive composition concerning this invention may further contain (e) electroconductive particle. In this case, since favorable conductivity or anisotropic conductivity can be imparted to the adhesive composition, it becomes possible to use it more suitably for bonding applications between circuit members having connection terminals or solar cell modules. Moreover, the connection resistance of the bonded structure obtained by electrically connecting through the said adhesive composition can be reduced more fully.

Further, the present inventors have found that the adhesive composition is useful for connection of members having connection terminals. The adhesive composition according to the present invention may be used to electrically connect a first connection terminal disposed on a principal surface of a first substrate and a second connection terminal disposed on a principal surface of a second substrate, and disposed on a principal surface of a substrate. You may use it in order to electrically connect the said connection terminal of the solar cell which has a connection terminal, and a wiring member.

A connection structure according to one aspect of the present invention includes a first circuit member having a first substrate and a first connection terminal disposed on the principal surface of the first substrate, a second substrate and a first circuit member disposed on the principal surface of the second substrate. A second circuit member having two connection terminals, and a connection member disposed between the first circuit member and the second circuit member, wherein the connection member contains a cured product of the adhesive composition, and the first connection terminal and The second connection terminal is electrically connected. In the connected structure according to one aspect of the present invention, when the connection member contains the cured product of the adhesive composition, the connection resistance and adhesive strength of the connected structure can be improved.

In the bonded structure according to one aspect of the present invention, at least one of the first substrate and the second substrate may be made of a base material containing a thermoplastic resin having a glass transition temperature of 200°C or less. In this case, the adhesive strength in the bonded structure using the adhesive composition can be further improved.

In the connection structure according to one aspect of the present invention, at least one of the first substrate and the second substrate is a substrate containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. may be configured. In this case, even when the first circuit member or the second circuit member having a substrate made of the specific material (material having low heat resistance) is used, low-temperature curing is possible by using the adhesive composition according to the present invention. Thermal damage to the first circuit member or the second circuit member can be reduced. In addition, wettability between the substrate made of the specific material and the adhesive composition is improved, so that the adhesive strength can be further improved. With these, in the case of using a substrate composed of the above specific material, excellent connection reliability can be obtained.

In the connection structure according to one aspect of the present invention, the first substrate is composed of a substrate containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate, and the second substrate is , a form composed of a base material containing at least one selected from the group consisting of polyimide resin and polyethylene terephthalate may be used. In this case, even when the first circuit member or the second circuit member having a substrate made of the specific material is used, since low-temperature curing is possible by using the adhesive composition according to the present invention, the first circuit member or the second circuit member Thermal damage to circuit members can be reduced. In addition, wettability between the substrate made of the specific material and the adhesive composition is improved, so that the adhesive strength can be further improved. With these, in the case of using a substrate composed of the above specific material, excellent connection reliability can be obtained.

A connection structure according to another aspect of the present invention includes a substrate and a solar cell having a connection terminal disposed on a main surface of the substrate, a wiring member, and a connection member disposed between the solar cell and the wiring member. , The connection member contains a cured product of the adhesive composition, and the connection terminal and the wiring member are electrically connected. In the connected structure according to another aspect of the present invention, when the connection member contains the cured product of the adhesive composition, the connection resistance and adhesive strength of the connected structure can be improved.

ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition excellent in low-temperature curability and storage stability can be provided. Such an adhesive composition can improve storage stability compared to the case where the alkyl boron compound described in Patent Document 3 is used. In addition, the adhesive composition according to the present invention is excellent in the balance of low-temperature curing properties and storage stability. Since the adhesive composition according to the present invention is excellent in storage stability, excellent adhesive strength and connection resistance can be obtained even when the adhesive composition is stored for a long period of time. Further, in the adhesive composition according to the present invention, excellent adhesive strength and connection resistance can be obtained regardless of whether or not the adhesive composition is stored for a long period of time. In addition, the adhesive composition according to the present invention can maintain stable performance (adhesive strength and connection resistance) even after a long-term reliability test (high temperature and high humidity test) regardless of whether or not the adhesive composition is stored for a long time. The present invention can provide a bonded structure using such an adhesive composition.

1 is a schematic cross-sectional view showing a bonded structure according to a first embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view showing a manufacturing method of the bonded structure shown in FIG. 1 .
3 is a schematic cross-sectional view showing a connection structure according to a second embodiment of the present invention.
FIG. 4 is a schematic cross-sectional view showing a manufacturing method of the bonded structure shown in FIG. 3 .
5 is a schematic cross-sectional view showing a connection structure according to a third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail. In the present specification, "(meth)acrylic acid" means acrylic acid and methacrylic acid corresponding thereto, and "(meth)acrylate" means acrylate and methacrylate corresponding thereto, and " "(meth)acrylic resin" means an acrylic resin and a methacrylic resin corresponding thereto, and "(meth)acryloyl group" means an acryloyl group and a methacryloyl group corresponding thereto, and "(meth)acryloyl group" means An acryloyloxy group” means an acryloyloxy group and a methacryloyloxy group corresponding thereto.

In addition, in this specification, "weight average molecular weight" means the value measured by gel permeation chromatography (GPC) using the calibration curve by standard polystyrene according to the conditions shown below.

(Measuring conditions)

Apparatus: GPC-8020 manufactured by Tosoh Corporation

Detector: RI-8020 manufactured by Tosoh Corporation

Column: Gelpack GL-A-160-S+GL-A150 manufactured by Hitachi Chemical Co., Ltd.

Sample concentration: 120 mg/3 ml

Solvent: tetrahydrofuran

Injection volume: 60 μl

Pressure: 30kgf/cm2

Flow rate: 1.00 ml/min

<Adhesive composition>

The adhesive composition according to the present embodiment contains (a) a thermoplastic resin, (b) a radical polymerizable compound, (c) a radical polymerization initiator, and (d) a complex containing boron.

((a) thermoplastic resin)

(a) A thermoplastic resin is a high-viscosity liquid state by heating, freely deformed by an external force, and when the external force is removed by cooling, it becomes hard while maintaining its shape, and this process can be repeated. means a resin (polymer) with Further, (a) the thermoplastic resin may be a resin (polymer) having a reactive functional group having the above properties. (a) The glass transition temperature (Tg) of the thermoplastic resin is preferably -30°C or higher, more preferably -25°C or higher, and still more preferably -20°C or higher. (a) The glass transition temperature of the thermoplastic resin is preferably 190°C or less, more preferably 170°C or less, still more preferably 150°C or less, particularly preferably 130°C or less, and extremely preferably 110°C or less.

(a) Thermoplastic resins include, for example, phenoxy resins, polyurethane resins, polyesterurethane resins, butyral resins (eg polyvinyl butyral resins), (meth)acrylic resins, polyimide resins and polyamide resins. , and copolymers having structural units derived from vinyl acetate (vinyl acetate copolymers, for example, ethylene-vinyl acetate copolymers). These can be used individually by 1 type or in mixture of 2 or more types. In addition, a siloxane bond or a fluorine substituent may be contained in these (a) thermoplastic resins. These are preferably in a state in which the resins to be mixed are completely compatible, or in a state in which microphase separation occurs and becomes cloudy.

When the adhesive composition is used in the form of a film, (a) the larger the weight average molecular weight of the thermoplastic resin, the easier it is to obtain good film formability, and the melt viscosity affecting the fluidity as a film adhesive composition can be set over a wide range there is. (a) The weight average molecular weight of the thermoplastic resin is preferably 5000 or more, more preferably 7000 or more, still more preferably 10000 or more, particularly preferably 20000 or more, and very preferably 25000 or more. (a) When the weight average molecular weight of the thermoplastic resin is 5000 or more, good film formability tends to be easily obtained. (a) The weight average molecular weight of the thermoplastic resin is preferably 150000 or less, more preferably 100000 or less, still more preferably 80000 or less, particularly preferably 70000 or less, and very preferably 65000 or less. (a) When the weight average molecular weight of the thermoplastic resin is 150000 or less, good compatibility with other components tends to be easily obtained.

The blending amount of the (a) thermoplastic resin in the adhesive composition is preferably 5% by mass or more, and more preferably 15% by mass or more, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). It is preferable, 25 mass % or more is more preferable, and 35 mass % or more is especially preferable. (a) When the compounding amount of the thermoplastic resin is 5% by mass or more, when the adhesive composition is used in the form of a film, particularly good film formability tends to be obtained. (a) The blending amount of the thermoplastic resin is preferably 80% by mass or less, more preferably 70% by mass or less, and 60% by mass, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). % or less is more preferable, and 50 mass % or less is especially preferable. (a) When the blending amount of the thermoplastic resin is 80% by mass or less, good fluidity of the adhesive composition tends to be easily obtained.

((b) radically polymerizable compound)

(b) A radically polymerizable compound means a compound that undergoes radical polymerization by the action of a radical polymerization initiator. (b) The radically polymerizable compound may be a compound that itself generates radicals by applying activation energy such as light or heat. (b) As the radically polymerizable compound, a compound having a functional group (a vinyl group, a (meth)acryloyl group, an allyl group, a maleimide group, etc.) that polymerizes with an active radical can be suitably used, for example.

(b) Specifically as a radically polymerizable compound, Oligomers, such as an epoxy (meth)acrylate oligomer, a urethane (meth)acrylate oligomer, a polyether (meth)acrylate oligomer, and a polyester (meth)acrylate oligomer; trimethylolpropane tri(meth)acrylate; polyethylene glycol di(meth)acrylate; polyalkylene glycol di(meth)acrylate; dicyclopentenyl (meth)acrylate; dicyclopentenyloxyethyl (meth)acrylate; neopentyl glycol di(meth)acrylate; dipentaerythritol hexa(meth)acrylate; isocyanuric acid-modified bifunctional (meth)acrylate; isocyanuric acid-modified trifunctional (meth)acrylate; bisphenoxyethanol fluorene (meth)acrylate; Epoxy (meth)acrylate obtained by adding (meth)acrylic acid to the glycidyl group of bisphenol fluorene diglycidyl ether; compounds obtained by introducing a (meth)acryloyloxy group into a compound obtained by adding ethylene glycol or propylene glycol to the glycidyl group of bisphenol fluorene diglycidyl ether; Compounds represented by the following general formula (B) or general formula (C), and the like are exemplified.

[In formula (B), R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a methyl group, and a and b each independently represent an integer of 1 to 8]

[In formula (C), R ¹¹ and R ¹² each independently represent a hydrogen atom or a methyl group, and c and d each independently represent an integer of 0 to 8]

Further, as the (b) radically polymerizable compound, even if it is a compound that exhibits a solid state without fluidity, such as wax, crystal, glass, powder, etc., when left alone at 30 ° C., it can be used without particular limitation. As such (b) radically polymerizable compound, specifically, N,N'-methylene bisacrylamide, diacetone acrylamide (alias: diacetone acrylamide), N-methylol acrylamide, N-phenyl methacryl Amide, 2-acrylamide-2-methylpropanesulfonic acid, tris(2-acryloyloxyethyl)isocyanurate, N-phenylmaleimide, N-(o-methylphenyl)maleimide, N-(m-methylphenyl) ) Maleimide, N-(p-methylphenyl)maleimide, N-(o-methoxyphenyl)maleimide, N-(m-methoxyphenyl)maleimide, N-(p-methoxyphenyl)maleimide, N-methylmaleimide, N-ethylmaleimide, N-octylmaleimide, 4,4'-diphenylmethanebismaleimide, m-phenylenebismaleimide, 3,3'-dimethyl-5,5'- Diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, N-methacryloxymaleimide, N-acryloxymaleimide, 1,6-bismaleimide Mid-(2,2,4-trimethyl)hexane, N-methacryloyloxysuccinic acid imide, N-acryloyloxysuccinic acid imide, 2-naphthyl methacrylate, 2-naphthyl acrylate, pentachloride Erythritol tetraacrylate, divinylethylene urea, divinylpropylene urea, 2-polystyrylethyl methacrylate, N-phenyl-N'-(3-methacryloyloxy-2-hydroxypropyl)-p- Phenylenediamine, N-phenyl-N'-(3-acryloyloxy-2-hydroxypropyl)-p-phenylenediamine, tetramethylpiperidylmethacrylate, tetramethylpiperidylacrylate, penta Methyl piperidyl methacrylate, pentamethyl piperidyl acrylate, octadecyl acrylate, N-t-butyl acrylamide, N-(hydroxymethyl) acrylamide, compounds represented by the following formulas (D) to (M), etc. can be heard

[In formula (D), e represents an integer of 1 to 10]

[In formula (F), R ¹³ and R ¹⁴ each independently represent a hydrogen atom or a methyl group, and f represents an integer of 15 to 30]

[In formula (G), R ¹⁵ and R ¹⁶ each independently represent a hydrogen atom or a methyl group, and g represents an integer of 15 to 30]

[In formula (H), R ¹⁷ represents a hydrogen atom or a methyl group]

[In Formula (I), R ¹⁸ represents a hydrogen atom or a methyl group, and h represents an integer of 1 to 10]

[In formula (J), R ¹⁹ represents a hydrogen atom or an organic group represented by the following formula (i) or (ii), and i represents an integer of 1 to 10]

[In formula (K), R ²⁰ represents a hydrogen atom or an organic group represented by the following formula (iii) or (iv), and j represents an integer of 1 to 10]

[In formula (L), R ²¹ represents a hydrogen atom or a methyl group]

[In formula (M), R ²² represents a hydrogen atom or a methyl group]

Further, (b) as the radically polymerizable compound, urethane (meth)acrylate can be used. Urethane (meth)acrylate may be used independently or may be used together with (b) radically polymerizable compounds other than urethane (meth)acrylate. By using urethane (meth)acrylate alone or in combination with (b) radically polymerizable compounds other than urethane (meth)acrylate, flexibility is improved and adhesive strength can be further improved.

Although there is no restriction|limiting in particular as urethane (meth)acrylate, Urethane (meth)acrylate represented by the following general formula (N) is preferable. Here, the urethane (meth)acrylate represented by the following general formula (N) is an aliphatic diisocyanate or alicyclic diisocyanate, an aliphatic ester-based diol, an alicyclic ester-based diol, an aliphatic carbonate-based diol, and an alicyclic It can be obtained by a condensation reaction with at least one selected from the group consisting of carbonate-based diols.

[In Formula (N), R ²³ and R ²⁴ each independently represent a hydrogen atom or a methyl group, R ²⁵ represents an ethylene group or a propylene group, R ²⁶ represents a saturated aliphatic group or a saturated alicyclic group, and R ²⁷ represents, represents a saturated aliphatic group or saturated alicyclic group having an ester group, or a saturated aliphatic group or saturated alicyclic group having a carbonate group, and k represents an integer of 1 to 40; In Formula (N), R ²⁵ and R ²⁶ may be the same or different.]

The aliphatic diisocyanate or alicyclic diisocyanate constituting the urethane (meth)acrylate is tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methyl Pentane-1,5-diisocyanate, 2,2,4-trimethylhexamethylene-1,6-diisocyanate, 2,4,4-trimethylhexamethylene-1,6-diisocyanate, isophorone diisocyanate, cyclohexyl You may select from sildiisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated trimethyl xylylene diisocyanate, etc.

In addition, the aliphatic ester-based diol or alicyclic ester-based diol constituting the urethane (meth)acrylate is ethylene glycol, propylene glycol (alias: 1,2-propanediol), 1,3-propanediol, 1,3 -Butanediol, 1,4-butanediol, neopentylglycol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 2-methyl-2,4-pentane Diol, 2,4-dimethyl-2,4-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 1,6-hexanediol , 2,5-hexanediol, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 1,2-octanediol, 1,8-octanediol, 1,7- Heptanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, dodecanediol (such as 1,12-dodecanediol), pinacol, 1,4-butynediol, triethylene saturated or unsaturated low molecular weight glycols such as glycol, diethylene glycol, dipropylene glycol, cyclohexanedimethanol, and 1,4-cyclohexanedimethanol; Adipic acid, 3-methyladipic acid, 2,2,5,5-tetramethyladipic acid, maleic acid, fumaric acid, succinic acid, 2,2-dimethylsuccinic acid, 2-ethyl-2-methylsuccinic acid, 2, 3-dimethylsuccinic acid, oxalic acid, malonic acid, methylmalonic acid, ethylmalonic acid, butylmalonic acid, dimethylmalonic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid Poly obtained by dehydration condensation of dibasic acids such as taric acid, 3,3-dimethylglutaric acid, 2,4-dimethylglutaric acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid or their corresponding acid anhydrides ester diols; It may be selected from polyester diols obtained by ring-opening polymerization of cyclic ester compounds such as ε-caprolactone. Each of the aliphatic ester-based diols and alicyclic ester-based diols may be used alone or in combination of two or more.

Further, the aliphatic carbonate-based diol or alicyclic carbonate-based diol constituting the urethane (meth)acrylate is selected from polycarbonate diols obtained by reaction of at least one of the above-mentioned glycols and phosgene It can be. The polycarbonate-type diol obtained by reaction of the said glycols and phosgene can be used individually by 1 type or in mixture of 2 or more types.

From the viewpoint of further improving the adhesive strength, the weight average molecular weight of the urethane (meth)acrylate can be adjusted freely within the range of 5000 or more and less than 30000, and can be used suitably. When the weight average molecular weight of the urethane (meth) acrylate is within the above range, both flexibility and cohesion can be sufficiently obtained, the adhesive strength with organic substrates such as PET, PC, and PEN is further improved, and more excellent connection reliability can be obtained. Further, from the viewpoint of obtaining such an effect more sufficiently, the weight average molecular weight of the urethane (meth)acrylate is more preferably 8000 or more and less than 25000, more preferably 10000 or more and less than 25000, and particularly preferably 10000 or more and less than 20000 Do. Moreover, when this weight average molecular weight is 5000 or more, sufficient flexibility tends to be easily obtained, and when the weight average molecular weight is less than 30000, the decrease in fluidity of the adhesive composition tends to be suppressed.

The compounding amount of the urethane (meth)acrylate is preferably 5% by mass or more, and more preferably 10% by mass or more, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition) 15 mass% or more is more preferable, 25 mass% or more is particularly preferable, and 35 mass% or more is very preferable. When the compounding amount is 5% by mass or more, sufficient heat resistance tends to be easily obtained after curing. Further, the blending amount of the urethane (meth)acrylate is preferably 95% by mass or less, and more preferably 80% by mass or less, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition) 70 mass % or less is more preferable, 60 mass % or less is especially preferable, and 50 mass % or less is very preferable. When the said compounding quantity is 95 mass % or less, when using an adhesive composition as a film adhesive, there exists a tendency for favorable film formability to be obtained easily.

(b) The radical polymerizable compound may contain at least one type of each of a phosphoric acid group-containing vinyl compound (a vinyl compound having a phosphoric acid group) and a radical polymerizable compound other than the phosphoric acid group-containing vinyl compound. (b) The radically polymerizable compound is an N-vinyl compound selected from the group consisting of N-vinyl compounds and N,N-dialkylvinyl compounds, and a radically polymerizable compound other than the N-vinyl compound, each containing 1 You may include more than one species. The combined use of the phosphoric acid group-containing vinyl compound can further improve the adhesiveness of the adhesive composition to a substrate having connection terminals. Moreover, the bridge|bridging rate (crosslinking rate) of adhesive composition can be improved by the combined use of N-vinyl type compound.

The phosphoric acid group-containing vinyl compound is not particularly limited as long as it is a compound having a phosphoric acid group and a vinyl group, but compounds represented by the following general formulas (O) to (Q) are preferable.

[In Formula (O), R ²⁸ represents a (meth)acryloyloxy group, R ²⁹ represents a hydrogen atom or a methyl group, and l and m each independently represent an integer of 1 to 8. In Formula (O), R ²⁸ , R ²⁹ , l and m may be the same or different.]

[In Formula (P), R ³⁰ represents a (meth)acryloyloxy group, and n, o and p each independently represent an integer of 1 to 8. In addition, in formula (P), R ³⁰ groups, n groups, o groups, and p groups may be the same or different.]

[In Formula (Q), R ³¹ represents a (meth)acryloyloxy group, R ³² represents a hydrogen atom or a methyl group, and q and r each independently represent an integer of 1 to 8]

As a vinyl compound containing a phosphoric acid group, specifically, acid phosphoroxyethyl (meth)acrylate, acid phosphoroxypropyl (meth)acrylate, acid phosphoroxypolyoxyethylene glycol mono(meth)acrylate, acid phosphoroxypolyoxypropylene Glycol mono(meth)acrylate, 2,2'-di(meth)acryloyloxydiethyl phosphate, EO modified phosphoric acid di(meth)acrylate, phosphoric acid modified epoxy(meth)acrylate, 2-(meth)acrylo Iloxyethyl phosphate, vinyl phosphate, etc. are mentioned.

Specific examples of N-vinyl compounds include N-vinylimidazole, N-vinylpyridine, N-vinylpyrrolidone, N-vinylformamide, N-vinylcaprolactam, and 4,4'-vinylidenebis. (N,N-dimethylaniline), N-vinylacetamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, and the like.

Each of the compounding amounts of the phosphoric acid group-containing vinyl compound and the N-vinyl compound described above is independent of the compounding amount of the radical polymerizable compound other than the phosphoric acid group-containing vinyl compound and the N-vinyl compound, the adhesive component (conductivity in the adhesive composition 0.2 mass% or more is preferable, 0.3 mass% or more is more preferable, 0.5 mass% or more is still more preferable, 1.0 mass% or more is particularly preferable, and 1.5 mass% or more is based on the total mass of components excluding particles). % or more is highly preferred. There exists a tendency for high adhesive strength to become easy to obtain that the said compounding quantity is 0.2 mass % or more. Each of the compounding amounts of the above-mentioned phosphoric acid group-containing vinyl compound and N-vinyl compound is preferably 15% by mass or less, and preferably 10% by mass, based on the total mass of the adhesive component (components excluding the conductive particles in the adhesive composition). % or less is more preferable, 5 mass % or less is still more preferable, and 3 mass % or less is especially preferable. When the compounding amount is 15% by mass or less, the physical properties of the adhesive composition after curing are less likely to decrease, and reliability tends to be ensured.

In addition, the blending amount of (b) radically polymerizable compound excluding the above-mentioned phosphoric acid group-containing vinyl compound and N-vinyl compound is 5 Mass % or more is preferable, 10 mass % or more is more preferable, 15 mass % or more is more preferable, 25 mass % or more is particularly preferable, and 35 mass % or more is very preferable. When the compounding amount is 5% by mass or more, sufficient heat resistance tends to be easily obtained after curing. The blending amount of the (b) radically polymerizable compound excluding the above-mentioned phosphoric acid group-containing vinyl compound and N-vinyl compound is 95% by mass based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition) The following is preferable, 80 mass % or less is more preferable, 70 mass % or less is more preferable, 60 mass % or less is especially preferable, and 50 mass % or less is very preferable. When the said compounding quantity is 95 mass % or less, when using an adhesive composition as a film adhesive, there exists a tendency for favorable film formability to be obtained easily.

((c) radical polymerization initiator)

(c) As the radical polymerization initiator, a compound that generates radicals by application of energy from the outside, such as conventionally known organic peroxides and azo compounds, can be used. (c) As the radical polymerization initiator, organic peroxides having a one-minute half-life temperature of 90 to 175°C and a weight average molecular weight of 180 to 1000 are preferable from the viewpoint of excellent stability, reactivity, and compatibility. When the half-life temperature for 1 minute is within this range, the storage stability is further excellent, the radical polymerizability is sufficiently high, and it can be cured in a short time.

(c) As the radical polymerization initiator, specifically, 1,1,3,3-tetramethylbutylperoxyneodecanoate, di(4-t-butylcyclohexyl)peroxydicarbonate, di(2- Ethylhexyl) peroxydicarbonate, cumylperoxyneodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t-hexylperoxyneodecanoate, t -Butylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di( 2-ethylhexanoylperoxy)hexane, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyneoheptanoate, t-amylfer Oxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy-3,5,5-trimethylhexanoate, 3-hydroxy-1,1-dimethylbutylfer Oxineodecanoate, t-amylperoxyneodecanoate, di(3-methylbenzoyl)peroxide, dibenzoylperoxide, di(4-methylbenzoyl)peroxide, t-hexylperoxyisopropylmonocar Bonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di(3- Methylbenzoylperoxy)hexane, t-butylperoxy-2-ethylhexylmonocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t- organic peroxides such as butyl peroxybenzoate, dibutyl peroxytrimethyl adipate, t-amylperoxy normal octoate, t-amylperoxyisononanoate, and t-amylperoxybenzoate; 2,2'-azobis-2,4-dimethylvaleronitrile, 1,1'-azobis(1-acetoxy-1-phenylethane), 2,2'-azobisisobutyronitrile, 2, 2'-azobis(2-methylbutyronitrile), dimethyl-2,2'-azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), 1,1'-azo Azo compounds, such as bis (1-cyclohexane carbonitrile), etc. are mentioned. These compounds can be used individually by 1 type or in mixture of 2 or more types.

Further, (c) as the radical polymerization initiator, a compound that generates radicals when irradiated with light of 150 to 750 nm can be used. As such a compound, since it has a high sensitivity to light irradiation, for example, Photoinitiation, Photopolymerization, and Photocuring, J. -P. and α-aminoacetophenone derivatives and phosphine oxide derivatives described in Fouassier, Hanser Publishers (1995, p17 to p35). In addition to using these compounds individually by 1 type or in mixture of 2 or more types, you may mix and use these compounds with the said organic peroxide or an azo compound.

The blending amount of the above (c) radical polymerization initiator is preferably 0.5% by mass or more, more preferably 1% by mass or more, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition), 2 mass % or more is more preferable, 3 mass % or more is especially preferable, and 5 mass % or more is very preferable. When the compounding amount is 0.5% by mass or more, the adhesive composition tends to sufficiently harden. The blending amount of the above (c) radical polymerization initiator is preferably 40% by mass or less, more preferably 30% by mass or less, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition), 20 mass % or less is more preferable, and 10 mass % or less is especially preferable. When the compounding amount is 40% by mass or less, the storage stability tends to be less likely to decrease.

((d) a complex containing boron)

(d) The boron-containing complex (hereinafter referred to as "component (d)") is a compound represented by the following general formula (A). Component (d) contains a boron compound and ammonia or an amine compound as a basic substance for the boron compound.

[In Formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an aryl group, and R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, Representing an alkyl group having 1 to 18 carbon atoms, an organic group represented by the following general formula (a1), or an organic group represented by the following general formula (a2)]

[In Formula (a1), R ^7a represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ^7b represents a hydrogen atom, an amino group, an alkoxy group, or an alkyl group having 1 to 10 carbon atoms. In addition, s and t each independently represent an integer from 1 to 10]

[In Formula (a2), R ⁸ represents an alkyl group having 1 to 10 carbon atoms. In addition, u represents an integer from 1 to 10]

As a boron compound contained in component (d), an alkyl diaryl borane, a dialkyl aryl borane, a trialkyl borane, a triaryl borane, a boron hydride, etc. are mentioned. The boron compound is preferably a trialkylborane from the viewpoint of more excellent low-temperature curability. The boron compound may be a compound having a plurality of the structures of these compounds in the molecule, or a compound having the structures of the above compounds in the main chain and/or side chain of the polymer.

As the alkyl group bonded to the boron atom in the boron compound, a straight-chain, branched-chain or cyclic alkyl group can be used. Specific examples of the alkyl group having 1 to 18 carbon atoms include methyl group, trifluoromethyl group, ethyl group, n-butyl group, hexyl group, octyl group, 2-ethylhexyl group, decyl group, dodecyl group, octadecyl group, propyl group, iso Propyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, 1-ethylpentyl group, cyclopentyl group, cyclohexyl group, isopentyl group, heptyl group, nonyl group, undecyl group, tert-ox A til group etc. are mentioned. Among these, an ethyl group, an isopropyl group, and an n-butyl group are preferable from the viewpoint of more excellent low-temperature curability. 1-12 are preferable and, as for carbon number of an alkyl group, 1-5 are more preferable from a viewpoint which low-temperature hardenability is more excellent. Each of the alkyl groups bonded to the boron atom in the boron compound may be the same as or different from each other.

Specific examples of the aryl group bonded to the boron atom in the boron compound include a phenyl group, p-tolyl group, m-tolyl group, mesityl group, xylyl group, p-tert-butylphenyl group (4-tert-butylphenyl group), p -Methoxyphenyl group, biphenyl group, naphthyl group, 4-methylnaphthyl group, etc. are mentioned. Among these, a phenyl group, a p-tert-butylphenyl group, and a 4-methylnaphthyl group are preferred, and a phenyl group is more preferred, from the viewpoints of low-temperature curability and storage stability. Each of the aryl groups bonded to the boron atom in the boron compound may be the same as or different from each other.

Examples of the amine compound used as the basic substance of component (d) include alkylamines, dialkylamines, trialkylamines, amines having an organic group represented by the general formula (a1), and amines having an organic group represented by the general formula (a2) etc. can be mentioned. Among these, amines having an organic group represented by the general formula (a1) and amines having an organic group represented by the general formula (a2) are preferred from the viewpoint of low-temperature curability and storage stability. As the amine compound, a compound having a plurality of the structures of these compounds in the molecule or a compound having the structures of the above compounds in the main chain and/or side chain of the polymer may be used.

In particular, among the above amine compounds, amines having an organic group represented by the general formula (a1) are preferred from the viewpoint of low-temperature curability and storage stability, and have an organic group represented by the general formula (a1) and two or more amino groups is more preferable, and an amine having two or more organic groups represented by the general formula (a1) in which R ^7a and R ^7b are hydrogen atoms is still more preferable. In this case, solubility in thermoplastic resins, radically polymerizable compounds and solvents is improved, and low-temperature curing properties can be further improved.

As the alkyl group bonded to the nitrogen atom in the amine compound, a straight-chain, branched-chain or cyclic alkyl group can be used. Specific examples of the alkyl group having 1 to 18 carbon atoms include methyl group, trifluoromethyl group, ethyl group, n-butyl group, hexyl group, octyl group, 2-ethylhexyl group, decyl group, dodecyl group, octadecyl group, propyl group, iso Propyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, 1-ethylpentyl group, cyclopentyl group, cyclohexyl group, isopentyl group, heptyl group, nonyl group, undecyl group, tert-ox A til group etc. are mentioned. Among these, the n-butyl group is preferable from the viewpoint of low-temperature curability and storage stability. 1-12 are preferable, and, as for carbon number of an alkyl group, 1-6 are more preferable from a viewpoint of low-temperature hardenability and storage stability.

In general formula (a1), as R ^7a , a hydrogen atom and an alkyl group having 1 to 5 carbon atoms are preferable. As R ^7b , a hydrogen atom and an alkyl group having 1 to 5 carbon atoms are preferable. As carbon number of the alkoxy group of R ^7b , 1-3 are preferable. As s, the integer of 1-5 is preferable. s may be an integer of 1 to 3 or an integer of 1 to 2. As t, an integer of 1 to 3 is preferable, and an integer of 1 to 2 is more preferable.

In general formula (a2), as R< ⁸ >, a C1-C5 alkyl group is preferable, a C1-C3 alkyl group is more preferable, and a C1-C2 alkyl group is still more preferable. As u, an integer of 1 to 5 is preferable, and an integer of 1 to 3 is more preferable.

Specific examples of the compound represented by the general formula (A) include triethylborane 1,3-diaminopropane, triethylborane N-(2-aminoethyl)ethane-1, from the viewpoint of low-temperature curability and storage stability. 2-diamine (alias: triethylborane N-(2-aminoethyl)-1,2-ethanediamine), triethylborane 3-methoxy-1-amine propane (alias: triethylborane 3-methoxypropylamine) ), tri-n-butylborane 3-methoxy-1-amine propane (alias: tri-n-butylborane 3-methoxypropylamine) and tri-n-butylborane 3-ethoxy-1-amine propane ( Alias: tri-n-butylborane 3-ethoxypropylamine), at least one selected from the group consisting of is preferred.

As component (d), a combination of trialkylborane and an amine having an organic group represented by general formula (a1) or an organic group represented by general formula (a2) is preferable. When the component (d) is a complex having such a structure, the improvement of the low-temperature curability and the improvement of the storage stability of the adhesive composition are obtained in a more well-balanced manner.

As the component (d), specifically, a complex obtained by a conventional synthetic method described in Japanese Patent Publication No. 7-72264 or the like can be used. For example, when obtaining a trialkylborane-amine complex, a trialkylborane-amine complex can be obtained by adding a trialkylborane-containing tetrahydrofuran (THF) solution in an amine solution.

(d) In addition to using a component individually by 1 type, you may mix and use 2 or more types.

(d) The compounding amount of the component is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and 1.0% by mass based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). More than that is more preferable, and 1.5 mass % or more is particularly preferable. When the blending amount of the component (d) is 0.1% by mass or more, the effect of accelerating the reactivity of the radical polymerization initiator tends to be sufficiently easily obtained. The blending amount of the component (d) is preferably 20% by mass or less, more preferably 15% by mass or less, and 10% by mass based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). The following is more preferable, and 5 mass % or less is especially preferable. When the compounding amount of the component (d) is 20% by mass or less, the storage stability of the adhesive composition tends to be less likely to decrease.

((e) conductive particles)

(e) Conductive particles may be particles having conductivity on the whole or surface, but when used for connection of members having connection terminals, particles having an average particle size smaller than the distance between connection terminals are preferable.

(e) Examples of the conductive particles include metal particles composed of metals such as Au, Ag, Ni, Cu, Pd, or solder, and particles composed of carbon or the like. Further, (e) the conductive particles may be particles having a non-conductive glass, ceramic or plastic or the like as a nucleus and covering the nucleus with the metal, metal particle or carbon. Since the particles in which the plastic core is coated with the metal, metal particles or carbon, and the hot-melting metal particles have deformability by heating and pressing, the contact area with the electrode increases during connection and reliability is improved, so ( e) It is preferable as a conductive particle. (e) The conductive particles may be, for example, particles obtained by coating silver on metal particles containing copper. Further, (e) as the conductive particles, a metal powder having a shape in which many fine metal particles are connected in a chain shape as described in Japanese Patent Laid-Open No. 2005-116291 can also be used.

In addition, by using these (e) fine particles whose surfaces are further coated with a polymer resin or the like, or particles in which an insulating layer containing an insulating material is formed on the surface of (e) conductive particles by a method such as hybridization Short circuit due to contact between particles when the compounding amount of conductive particles is increased is suppressed, and insulation between electrode circuits is improved. Therefore, you may use these particle|grains individually or mixing with (e) electroconductive particle as appropriate.

(e) The average particle diameter of the conductive particles is preferably 1 to 18 μm, for example, from the viewpoint of excellent dispersibility and conductivity. When such (e) conductive particles are contained, the adhesive composition can be suitably used as an anisotropic conductive adhesive. (e) The average particle diameter of the conductive particles can be measured using a laser diffraction type particle size distribution analyzer (eg, laser diffraction type SALD-2100 manufactured by Shimadzu Corporation).

(e) The blending amount of the conductive particles is not particularly limited, but is preferably 0.1% by volume or more, and 0.2% by volume or more based on the total volume of the adhesive components (components excluding the conductive particles in the adhesive composition). More preferably, 0.5% by volume or more is still more preferable, and 1% by volume or more is particularly preferable. When the compounding amount is 0.1% by volume or more, the decrease in conductivity tends to be suppressed. (e) The blending amount of the conductive particles is preferably 30% by volume or less, more preferably 10% by volume or less, based on the total volume of the adhesive component (components excluding the conductive particles in the adhesive composition), and 5% by volume % or less is more preferable. When the compounding amount is 30% by volume or less, short circuit tends to be less likely to occur. In addition, "volume %" is determined based on the volume of each component before hardening at 23 degreeC, but the volume of each component can be converted from weight to volume using specific gravity. In addition, the component is put into a container containing an appropriate solvent (water, alcohol, etc.) that can sufficiently wet the component without dissolving or swelling the component, such as a measuring cylinder, and the increased volume can be obtained as the volume of the component. .

(other ingredients)

The adhesive composition according to the present embodiment may contain a stabilizer for controlling the curing rate and further improving the storage stability. As such a stabilizer, known compounds can be used without particular limitation, but quinone derivatives such as benzoquinone and hydroquinone; phenol derivatives such as 4-methoxyphenol and 4-t-butylcatechol; aminoxyl derivatives such as 2,2,6,6-tetramethylpiperidine-1-oxyl and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl; Hindered amine derivatives, such as tetramethyl piperidyl methacrylate, etc. are preferable. A stabilizer can be used individually by 1 type or in mixture of 2 or more types.

The blending amount of the stabilizer is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, and 0.02% by mass or more based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). more preferable When the compounding amount is 0.005% by mass or more, the curing rate is easily controlled and the storage stability tends to be improved. The blending amount of the stabilizer is preferably 10% by mass or less, more preferably 8% by mass or less, and 5% by mass or less based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). more preferable When the blending amount is 10% by mass or less, compatibility with other components tends to be less likely to decrease.

In addition, the adhesive composition according to the present embodiment may appropriately contain an adhesion auxiliary agent such as a coupling agent represented by an alkoxysilane derivative and a silazane derivative, an adhesion improver, and a leveling agent. As the coupling agent, specifically, a compound represented by the following general formula (R) is preferable. A coupling agent can be used individually by 1 type or in mixture of 2 or more types.

[In Formula (R), R ³³ , R ³⁴ and R ³⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxycarbonyl group having 1 to 5 carbon atoms, or an aryl group; R ³⁶ is (meth)acryloyl group, vinyl group, isocyanate group, imidazole group, mercapto group, amino group, methylamino group, dimethylamino group, benzylamino group, phenylamino group, cyclohexylamino group, morpholino group, piperazino group, urea Represents a pot or glycidyl group, v represents an integer of 1 to 10]

The adhesive composition according to the present embodiment may contain a rubber component for the purpose of relieving stress and improving adhesion. The rubber component means a component that exhibits rubber elasticity (JIS K6200) in a state as it is or a component that exhibits rubber elasticity by reaction. The rubber component may be solid or liquid at room temperature (25°C), but is preferably liquid from the viewpoint of improving fluidity. As the rubber component, a compound having a polybutadiene skeleton is preferable. The rubber component may have a cyano group, a carboxyl group, a hydroxyl group, a (meth)acryloyl group or a morpholino group. Further, from the viewpoint of improving adhesiveness, a rubber component containing a cyano group or carboxyl group, which is a highly polar group, in a side chain or terminal is preferable. In addition, even if it has a polybutadiene skeleton, when showing thermoplasticity, it is classified as (a) thermoplastic resin, and when showing radical polymerizability, it is classified as (b) radical polymerizable compound.

As the rubber component, specifically, polyisoprene, polybutadiene, carboxyl terminal polybutadiene, hydroxyl terminal polybutadiene, 1,2-polybutadiene, carboxyl terminal 1,2-polybutadiene, hydroxyl terminal 1,2-polybutadiene, acrylic Rubber, styrene-butadiene rubber, hydroxyl-terminated styrene-butadiene rubber, acrylonitrile-butadiene rubber, acrylonitrile-butadiene rubber having a carboxyl group, hydroxyl group, (meth)acryloyl group or morpholino group at the polymer terminal, carboxylation Nitrile rubber, hydroxyl group terminal poly(oxypropylene), alkoxysilyl group terminal poly(oxypropylene), poly(oxytetramethylene) glycol, polyolefin glycol, etc. are mentioned.

Further, as the rubber component having the above-mentioned highly polar group and being liquid at room temperature, specifically, liquid acrylonitrile-butadiene rubber, a liquid acrylonitrile having a carboxyl group, a hydroxyl group, a (meth)acryloyl group or a morpholino group at the polymer terminal. Nitrile-butadiene rubber, liquid carboxylated nitrile rubber, etc. are mentioned. As for the compounding quantity of acrylonitrile which has a polar group, 10-60 mass % is preferable.

These rubber components can be used individually by 1 type or in mixture of 2 or more types.

In addition, the adhesive composition according to the present embodiment may contain organic particulates for the purpose of relieving stress and improving adhesiveness. As for the average particle diameter of organic particulates, 0.05-1.0 micrometers are preferable, for example. In addition, when the organic particulates contain the above-mentioned rubber component, they are classified as not organic particulates but rubber components, and when the organic particulates contain the above-mentioned (a) thermoplastic resin, they are not organic particulates but (a) thermoplastic resin. classified as

Specifically, as organic particulates, polyisoprene, polybutadiene, carboxyl terminal polybutadiene, hydroxyl group terminal polybutadiene, 1,2-polybutadiene, carboxyl terminal 1,2-polybutadiene, acrylic rubber, styrene-butadiene rubber, acrylo Nitrile-butadiene rubber, acrylonitrile-butadiene rubber having a carboxyl group, hydroxyl group, (meth)acryloyl group or morpholino group at the polymer terminal, carboxylated nitrile rubber, hydroxyl group terminal poly(oxypropylene), alkoxysilyl group terminal poly (oxypropylene), poly(oxytetramethylene) glycol, polyolefin glycol, alkyl (meth)acrylate-butadiene-styrene copolymer, alkyl (meth)acrylate-silicone copolymer or silicone-(meth)acrylic copolymer, or any of these and organic particulates containing composites.

In addition, the adhesive composition used for the bonded structure described later, in which the substrate is composed of a base material containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate and polyethylene naphthalate, even if it contains silicon fine particles. do.

The adhesive composition used for the bonded structure in which the substrate is composed of a base material containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate contains silicon fine particles to sufficiently relieve internal stress. Therefore, the adhesive strength to polyethylene terephthalate, polycarbonate, and polyethylene naphthalate is further improved, and the adhesive strength to members having connection terminals can be further improved. In addition, more stable performance can be maintained even after a long-term reliability test.

As the silicon fine particles, fine particles of a polyorganosilsesquioxane resin having rubber elasticity are known, and spherical or irregular shape silicon fine particles are used. Further, from the viewpoint of dispersibility and relaxation of internal stress, it is preferable that the silicone fine particles have a weight average molecular weight of 1,000,000 or more. In addition, it is preferable that the silicone fine particles have a three-dimensional cross-linked structure. These silicone fine particles are highly dispersible in resin and have further excellent stress relaxation properties after curing. Since silicone microparticles having a weight average molecular weight of 1 million or more and/or silicone microparticles having a three-dimensional cross-linked structure have low solubility in polymers (thermoplastic resins, etc.), monomers, or solvents, the above-mentioned effects can be obtained even more remarkably. can Here, "having a three-dimensional crosslinked structure" indicates that the polymer chain has a three-dimensional network structure. Further, the glass transition temperature of the silicon fine particles is preferably -130°C or more and -20°C or less, and more preferably -120°C or more and -40°C or less. Such silicon fine particles can sufficiently relieve the internal stress of the adhesive composition as a circuit connection material.

Specifically, as the silicone fine particles having such a structure, an organopolysiloxane having at least two vinyl groups, an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms, and a platinum-based catalyst are reacted obtained silicon fine particles (for example, Japanese Unexamined Patent Publication (Sho) 62-257939); silicone fine particles obtained by using an organopolysiloxane having an alkenyl group, an organopolysiloxane having a hydrosilyl group, and a platinum-based catalyst (for example, Japanese Unexamined Patent Publication (Kokai) No. 63-77942); silicone fine particles obtained using diorganosiloxanes, monoorganosilsesquioxanes, triorganosiloxanes, and platinum-based catalysts (for example, Japanese Unexamined Patent Publication (Sho) 62-270660); Silicon microparticles obtained by adding dropwise a water/alcohol solution of methylsilanetriol and/or a partial condensate thereof to an aqueous alkali solution to cause a polycondensation reaction (for example, Japanese Patent No. 3970453) or the like can be used. In addition, in order to improve dispersibility and adhesion to the substrate, silicone fine particles to which an epoxy compound is added or copolymerized (for example, Japanese Patent Laid-Open No. 3-167228), silicone fine particles to which an acrylic acid ester compound is added or copolymerized, etc. can also be used

Further, in order to further improve the dispersibility, it is preferable to use silicon fine particles having a core-shell structure. As the core-shell structure, a structure having a surface layer (shell layer) having a glass transition temperature higher than the glass transition temperature of the nucleus material (core layer) on the surface of the nucleus material, and a structure having a graft layer (shell layer) outside the nucleus material (core layer) There is, and silicon particles having different compositions can be used in the core layer and the shell layer. Specifically, core-shell type silicone microparticles obtained by adding an alkaline substance or alkaline aqueous solution and organotrialkoxysilane to an aqueous dispersion of spherical silicone rubber microparticles, followed by a hydrolysis and condensation reaction (e.g., Japanese Patent No. 2832143); Core-shell type silicon fine particles as described in WO2009/051067 can also be used. In addition, silicone fine particles having a functional group such as a hydroxyl group, an epoxy group, a ketimine group, a carboxyl group, or a mercapto group at a molecular terminal or an intramolecular side chain can be used. Such silicone fine particles are preferable because their dispersibility to film-forming components and radically polymerizable substances is improved.

The average particle diameter of the silicon fine particles is preferably 0.05 to 25 μm, and more preferably 0.1 to 20 μm. When the average particle size is 0.05 μm or more, there is a tendency that the decrease in fluidity of the adhesive composition due to the increase in surface area is suppressed. In addition, when the average particle diameter is 25 μm or less, there is a tendency that the relaxation of internal stress is sufficiently exhibited.

The compounding amount of the silicone fine particles is preferably 3% by mass or more, and more preferably 5% by mass or more, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). When the blending amount of the silicon fine particles is 3% by mass or more, the internal stress tends to be sufficiently relieved. The blending amount of the silicone fine particles is preferably 40% by mass or less, and more preferably 30% by mass or less, based on the total mass of the adhesive components (components excluding the conductive particles in the adhesive composition). When the blending amount of the silicone fine particles is 40% by mass or less, the decrease in flexibility (modulus of elasticity, elongation) of the adhesive composition is suppressed, and the adhesive strength tends to be less likely to decrease.

These silicone fine particles can be used individually by 1 type or in mixture of 2 or more types.

The adhesive composition according to the present embodiment can be used in a paste form when the adhesive composition is liquid at room temperature. When the adhesive composition is solid at room temperature, in addition to heating and using it, you may paste it using a solvent. As the usable solvent, a solvent that is not reactive with the adhesive composition and additives and exhibits sufficient solubility is preferable, and a solvent having a boiling point at normal pressure of 50 to 150°C is preferable. If the boiling point is 50°C or higher, volatilization will be reduced when left at room temperature, and use in an open system tends to be facilitated. In addition, when the boiling point is 150°C or less, volatilization of the solvent becomes easy, and reliability after adhesion tends to be less likely to decrease.

In addition, the adhesive composition according to the present embodiment can be molded into a film and used as a film adhesive. The film adhesive according to the present embodiment contains the above adhesive composition. If necessary, a solution obtained by adding a solvent or the like to the adhesive composition is applied onto a peelable substrate such as a fluororesin film, a polyethylene terephthalate film, or a release paper, or a substrate such as a nonwoven fabric is impregnated with the solution to obtain a peelable substrate After loading on it, it can be used as a film by removing the solvent or the like. When used in the form of a film, it is more convenient in terms of handleability and the like. According to this embodiment, the adhesive sheet provided with a base material and a film adhesive is provided. In the adhesive sheet, the film adhesive is disposed on the substrate, forming, for example, an adhesive layer.

The adhesive composition according to the present embodiment can be bonded by using both heating and pressurization. As for heating temperature, the temperature of 100-200 degreeC is preferable. The pressure is preferably in a range that does not damage the adherend, and is generally preferably 0.1 to 10 MPa. It is preferable to perform these heating and pressurization in the range of 0.5 to 120 seconds, and it is possible to adhere also by heating at 120 to 190 degreeC, 3 MPa, and 10 seconds.

The adhesive composition according to the present embodiment can be used to electrically connect the first connection terminal disposed on the main surface of the first substrate and the second connection terminal disposed on the main surface of the second substrate. In addition, the adhesive composition according to the present embodiment can be used to electrically connect the connection terminal of a solar cell having a connection terminal disposed on the main surface of a substrate and a wiring member.

The adhesive composition according to the present embodiment can be used as an adhesive for adherends of the same type or as an adhesive for adherends of different types having different coefficients of thermal expansion. Specifically, the adhesive composition according to the present embodiment is an anisotropic conductive adhesive, a circuit connection material represented by silver paste, silver film, etc., an elastomer for CSP, an underfill material for CSP, a semiconductor element adhesive material represented by LOC tape, etc. can be used

For example, a first circuit member having a first circuit board and a first connection terminal disposed on the main surface of the first circuit board, and a second circuit board and a second connection terminal disposed on the main surface of the second circuit board. The second circuit member having a first connection terminal and the second connection terminal facing each other while the first connection terminal and the second connection terminal are electrically connected, the adhesive composition according to the embodiment or A connection structure of circuit members can be constituted by arranging the load with the load interposed therebetween. In such a case, the adhesive composition according to the present embodiment is useful as an adhesive for circuit connection.

<connection structure>

Next, a bonded structure using the adhesive composition described above and a manufacturing method thereof will be described. According to the present embodiment, a first circuit member having a first substrate and a first connection terminal disposed on the principal surface of the first substrate, and a second substrate and a second connection terminal disposed on the principal surface of the second substrate. Bonding the first circuit member and the second circuit member in a state where the first connection terminal and the second connection terminal are electrically connected by curing the adhesive composition in a state where the adhesive composition is interposed between the second circuit members , a method for manufacturing a connection structure is provided. Further, according to the present embodiment, the adhesive composition is cured between a substrate and a solar cell having connection terminals disposed on the main surface of the substrate and a wiring member in a state where the adhesive composition is interposed therebetween, so that the connection terminals and the wiring A manufacturing method of a connection structure is provided, wherein a solar cell and a wiring member are bonded in a state where the members are electrically connected.

1 is a schematic cross-sectional view showing a bonded structure according to a first embodiment. FIG. 2 is a schematic cross-sectional view showing a manufacturing method of the bonded structure shown in FIG. 1 . The connection structure 100 of the circuit member shown in FIG. 1 is obtained using the adhesive composition which does not contain (e) electroconductive particle.

The circuit member connection structure 100 shown in FIG. 1 includes a circuit member (first circuit member) 10, a circuit member (second circuit member) 20, and a connection member 30. The circuit member 10 has a circuit board (first board) 12 and a connection terminal (first connection terminal) 14 disposed on a main surface 12a of the circuit board 12 . The circuit member 20 has a circuit board (second board) 22 and a connection terminal (second connection terminal) 24 disposed on a main surface 22a of the circuit board 22 .

The connection member 30 is disposed between the circuit member 10 and the circuit member 20 . The connection member 30 connects the circuit member 10 and the circuit member 20 so that the main surface 12a and the main surface 22a oppose each other substantially in parallel. In the connection structure 100, the connection terminal 14 and the connection terminal 24 are electrically connected by being in contact with each other while being opposed to each other. The connecting member 30 includes a cured product of an adhesive composition 30a described later.

The connection structure 100 can be manufactured as follows, for example. First, as shown in FIG. 2, the circuit member 10, the circuit member 20, and the adhesive composition 30a containing the said adhesive composition are prepared. The adhesive composition 30a is obtained by molding the adhesive composition into a film, for example. Next, the adhesive composition 30a is placed on the main surface 22a on which the connection terminals 24 in the circuit member 20 are formed. Then, the circuit member 10 is placed on the adhesive composition 30a so that the connecting terminals 14 face the connecting terminals 24 . Then, while heating the adhesive composition 30a through the circuit member 10 and the circuit member 20, while curing the adhesive composition 30a, it presses in the direction perpendicular to the main surfaces 12a and 22a, and the circuit member A connecting member 30 is formed between (10, 20). In this way, the connection structure 100 is obtained.

When the adhesive composition contains conductive particles, an anisotropic conductive film produced using such an adhesive composition is interposed between the opposing connection terminals and heated and pressurized to electrically connect the connection terminals to each other through the conductive particles. By adhering circuit members to each other, a connection structure of circuit members can be obtained. 3 is a schematic cross-sectional view showing a connection structure according to a second embodiment. FIG. 4 is a schematic cross-sectional view showing a manufacturing method of the bonded structure shown in FIG. 3 . The connection structure 200 of the circuit member shown in FIG. 3 is obtained using the adhesive composition containing (e) electroconductive particle.

The connection structure 200 of the circuit member shown in FIG. 3 is equipped with the same circuit member 10 and circuit member 20 as the connection structure 100, and the connection member 40. As shown in FIG. In the connection structure 200, the connection terminal 14 and the connection terminal 24 are disposed facing each other while being spaced apart from each other.

The connection member 40 is disposed between the circuit member 10 and the circuit member 20 . The connecting member 40 includes a cured product of an adhesive composition 40a described later, and has an adhesive component 42 and conductive particles 44 dispersed in the adhesive component 42 . The adhesive component 42 includes a cured product of an adhesive component 42a described later. In the connection structure 200, the conductive particles 44 come into contact with the connection terminals 14 and 24 between the opposing connection terminals 14 and 24, thereby connecting the connection terminals via the conductive particles 44. (14, 24) are electrically connected to each other.

The connection structure 200 can be manufactured as follows, for example. First, as shown in FIG. 4, the circuit member 10, the circuit member 20, and the adhesive composition 40a containing the said adhesive composition are prepared. The adhesive composition 40a is obtained by molding the adhesive composition into a film, for example. The adhesive composition 40a has an adhesive component 42a and conductive particles 44 dispersed in the adhesive component 42a. Then, the circuit member 10 and the circuit member 20 are connected via the adhesive composition 40a by the method similar to the method of obtaining the connection structure 100 of the said circuit member. In this way, the connection structure 200 is obtained.

At least one of the circuit board 12 and the circuit board 22 in the connection structures 100 and 200 of the circuit members may be made of a base material containing a thermoplastic resin having a glass transition temperature of 200°C or less. For example, even if at least one of the circuit board 12 and the circuit board 22 is comprised from the organic substrate containing at least 1 sort(s) selected from the group which consists of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. do. As a result, in the case of using an organic base material such as polyethylene terephthalate, polycarbonate, or polyethylene naphthalate, wettability with the adhesive composition in the circuit board is improved, thereby obtaining excellent adhesive strength even under low-temperature curing conditions. can Therefore, it is possible to maintain stable performance (adhesive strength and connection resistance) even after a long-term reliability test (high temperature and high humidity test), and excellent connection reliability can be obtained.

In addition, when one circuit board of the circuit board 12 and the circuit board 22 is comprised from the base material containing at least 1 sort(s) selected from the group which consists of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate , The circuit board 12 and the other circuit board of the circuit board 22 may be comprised from the base material containing at least 1 sort(s) selected from the group which consists of a polyimide resin and a polyethylene terephthalate. As a result, wettability and adhesive strength with the adhesive composition in the circuit board are further improved, and further excellent connection reliability can be obtained.

In addition, the circuit boards 12 and 22 are made of inorganic materials such as semiconductors, glass, or ceramics; organic substances such as polyethylene terephthalate, polyethylene naphthalate, polyimide resin or polycarbonate; It may be composed of a substrate containing a composite material such as glass/epoxy resin. Also, the circuit boards 12 and 22 may be flexible boards.

5 is a schematic cross-sectional view showing a connection structure according to a third embodiment. The solar cell module 300 shown in FIG. 5 includes solar cells 310a and 310b, a wiring member 320, and a connection member 330.

The solar cells 310a and 310b include a substrate 312, a surface electrode (connection terminal) 314 disposed on the surface (main surface) 312a of the substrate 312, and a back surface (main surface) of the substrate 312. ) 312b, and has a back electrode (connection terminal) 316 disposed above. The substrate 312 is made of, for example, a semiconductor, an inorganic substance such as glass or ceramic, or a composite material such as glass/epoxy resin. Also, the substrate 312 may be a flexible substrate. The surface 312a is a light receiving surface.

The wiring member 320 is a member for electrically connecting the solar cell 310a and other members, and electrically connects one solar cell to another, for example. In FIG. 5 , the front electrode 314 of the solar cell 310a and the back electrode 316 of the solar cell 310b are electrically connected by the wiring member 320 .

The connecting member 330 is disposed between the solar cell 310a and the wiring member 320, and between the solar cell 310b and the wiring member 320, respectively, and the solar cell 310a, 310b ) and the wiring member 320 are connected. The connection member 330 contains a cured product of the adhesive composition and contains an insulating material. The connecting member 330 may further contain conductive particles or may not contain conductive particles. When the connection member 330 contains conductive particles, the surface electrode 314 of the solar cell 310a and the wiring member 320 may be electrically connected through the conductive particles. In addition, the back electrode 316 of the solar cell 310b and the wiring member 320 may also be electrically connected through conductive particles. When the connection member 330 does not contain conductive particles, for example, the front electrode 314 of the solar cell 310a and/or the rear electrode 316 of the solar cell 310b is the wiring member 320 ) may be in contact with

In the solar cell module 300, the connection member 330 is constituted by a cured product of the adhesive composition. As a result, the adhesive strength of the connection member 330 between the solar cell 310a and the wiring member 320 and between the solar cell 310b and the wiring member 320 is sufficiently high, and the solar cell The connection resistance between (310a, 310b) and the wiring member 320 is sufficiently small. Moreover, even when it is placed in a high-temperature, high-humidity environment for a long period of time, a decrease in adhesive strength and an increase in connection resistance can be sufficiently suppressed. In addition, the connecting member 330 is a member that can be formed by heat treatment at a low temperature and for a short time. Therefore, the solar cell module shown in FIG. 5 can be manufactured without deteriorating the solar cells 310a and 310b at the time of connection, and can have higher reliability than before.

The solar cell module 300 replaces the circuit member 10 and the circuit member 20 in the manufacturing method of the connection structures 100 and 200 described above, and includes the solar cells 310a and 310b and the wiring member 320 ), it can be manufactured by the method similar to the manufacturing method of the above-mentioned connection structure.

In addition, in the connection structures 100 and 200 and the solar cell module 300, the adhesive composition used as the connection member does not need to be completely cured (the highest degree of curing that can be achieved under predetermined curing conditions). , it may be in a state of partial curing that gives rise to the above characteristics.

[Example]

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

<Thermoplastic resin>

(Preparation of polyester urethane resin)

A polyester urethane resin (trade name: UR-4800, manufactured by Toyobo Co., Ltd., weight average molecular weight: 32000, glass transition temperature: 106° C.) was dissolved in a 1:1 mixed solvent of methyl ethyl ketone and toluene, and the resin content was 30 mass A mixed solvent dissolution product of % was prepared.

(Preparation of phenoxy resin)

40 parts by mass of phenoxy resin (trade name: YP-50, manufactured by Nippon Steel Sumikin Chemical Co., Ltd., weight average molecular weight: 60000, glass transition temperature: 80°C) was dissolved in 60 parts by mass of methyl ethyl ketone, and solid content was 40 mass parts. A solution of % was prepared.

<Radically polymerizable compound>

(Synthesis of urethane acrylate (UA1))

In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser with a calcium chloride drying tube and a nitrogen gas introduction tube, poly(1,6-hexanediolcarbonate) having a number average molecular weight of 1000 (trade name: Duranol T5652, Asahi Kasei) Chemicals Co., Ltd.) 2500 parts by mass (2.50 mol) and isophorone diisocyanate (manufactured by Sigma-Aldrich) 666 parts by mass (3.00 mol) were uniformly added dropwise over 3 hours, and nitrogen gas was sufficiently introduced into the reaction vessel. After that, the mixture was reacted by heating to 70 to 75°C. To the reaction vessel, after adding 0.53 parts by mass of hydroquinone monomethyl ether (manufactured by Sigma-Aldrich) and 5.53 parts by mass of dibutyltin dilaurate (manufactured by Sigma-Aldrich), 2-hydroxyethyl acrylate (manufactured by Sigma-Aldrich) ) 238 mass parts (2.05 mol) was added, and it was made to react at 70 degreeC for 6 hours in an air atmosphere, and the urethane acrylate (UA1) was obtained. The weight average molecular weight of urethane acrylate was 15000.

(Preparation of vinyl compound (P-2M) having a phosphoric acid group)

As a vinyl compound having a phosphoric acid group, 2-(meth)acryloyloxyethyl phosphate (trade name: Light Ester P-2M, manufactured by Kyoeisha Chemical Co., Ltd.) was prepared.

<Complex containing boron>

(Synthesis of triethylborane 1,3-diaminopropane (TEB-DAP))

14.8 g (0.20 mol) of 1,3-propylenediamine was added to a three-necked flask containing a stirrer, a condenser, a thermometer, and a nitrogen gas inlet tube, and 13.1 g (0.13 mol) of triethylboron was dissolved in 100 ml of tetrahydrogen. A solution dissolved in furan (THF) was added dropwise while maintaining the temperature below about 40°C. After completion of the dropwise addition, triethylborane 1,3-diaminopropane (TEB-DAP) was obtained by stirring the mixture for about 0.5 hour.

(Synthesis of triethylborane N-(2-aminoethyl)ethane-1,2-diamine (TEB-DETA))

20.6 g (0.20 mol) of N-(2-aminoethyl)ethane-1,2-diamine was added to a three-necked flask containing a stirrer, a condenser, a thermometer, and a nitrogen gas inlet tube, and 13.1 g (0.13 mol) of A solution in which triethyl boron was dissolved in 100 ml of tetrahydrofuran (THF) was added dropwise while maintaining the temperature at about 40°C or lower. After completion of the dropwise addition, triethylborane N-(2-aminoethyl)ethane-1,2-diamine (TEB-DETA) was obtained by stirring the mixture for about 0.5 hour.

(Synthesis of tri-n-butylborane 3-methoxy-1-amine propane (TnBB-MOPA))

17.8 g (0.20 mol) of 3-methoxy-1-amine propane was added to a three-necked flask containing a stirrer, condenser, thermometer and nitrogen gas inlet tube, and 23.7 g (0.13 mol) of tri-n-butyl boron was dissolved in 100 ml of tetrahydrofuran (THF) and added dropwise while maintaining the temperature below about 40°C. After completion of the dropwise addition, tri-n-butylborane 3-methoxy-1-amine propane (TnBB-MOPA) was obtained by stirring the mixture for about 0.5 hour.

<Amine compound>

As an amine compound, N,N-dimethylaniline (abbreviation: DMA, manufactured by Sigma-Aldrich) was prepared.

<Radical polymerization initiator>

Dilauroyl peroxide (trade name: Peroyl L, manufactured by Nichiyu Co., Ltd.) was prepared.

<Conductive Particles>

(Production of conductive particles)

After forming a nickel layer with a thickness of 0.2 μm on the surface of the particles containing polystyrene as a nucleus, a gold layer with a thickness of 0.02 μm was formed on the outside of the nickel layer to produce conductive particles with an average particle diameter of 10 μm and specific gravity of 2.5.

<Examples 1 to 6 and Comparative Examples 1 to 4>

(Manufacture of adhesive for circuit connection)

As shown in Table 1 in solid mass ratio, a thermoplastic resin, a radical polymerizable compound and a radical polymerization initiator, and a boron-containing complex or amine compound were blended, and an adhesive component (excluding the conductive particles in the circuit connection adhesive) Component) based on the total volume, conductive particles were blended and dispersed at 1.5% by volume to obtain an adhesive for circuit connection. The obtained adhesive for circuit connection was applied onto a fluororesin film having a thickness of 80 μm using a coating device, and dried with hot air at 70° C. for 10 minutes to obtain a film-like adhesive for circuit connection having an adhesive layer thickness of 20 μm. .

(Measurement of connection resistance and adhesive strength)

A flexible circuit board (FPC) having 500 copper circuits having a line width of 25 μm, a pitch of 50 μm, and a thickness of 8 μm on a polyimide film using the film-like circuit connection adhesives of Examples 1 to 6 and Comparative Examples 1 to 4; It was interposed between 1.1 mm-thick glass (ITO, surface resistance of 20 ohm/square) in which the thin layer of ITO of 0.2 micrometer thickness was formed. This was heated and pressurized at 120°C and 2 MPa for 10 seconds using a thermocompression bonding device (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.), and connected over a width of 2 mm to obtain a bonded structure A (FPC/ITO) was produced. The resistance value between adjacent circuits of this bonded structure A was measured using a multimeter immediately after connection and after holding for 240 hours in a constant temperature and humidity chamber at 85°C and 85% RH (after high temperature and high humidity test). The resistance value was expressed as an average of 37 resistance points between adjacent circuits.

In addition, immediately after connection and after a high-temperature, high-humidity test, the adhesive strength of bonded structure A was measured by the 90-degree peeling method according to JIS-Z0237. Here, as a measuring device for adhesive strength, Toyo Baldwin Co., Ltd. Tensilon UTM-4 (peel rate: 50 mm/min, 25°C) was used.

A flexible film having 80 copper circuits having a line width of 150 μm, a pitch of 300 μm, and a thickness of 8 μm on a polyimide film (Tg: 350° C.) of the film-like circuit connection adhesives of Examples 1 to 6 and Comparative Examples 1 to 4. It was interposed between the circuit board (FPC) and a PET substrate (Ag) having a thickness of 0.1 μm on which a thin layer of Ag paste having a thickness of 5 μm was formed. This was heated and pressurized at 120°C and 2 MPa for 20 seconds using a thermocompression bonding device (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.) and connected over a width of 2 mm to obtain bonded structure B (FPC/Ag) was produced. The resistance value between adjacent circuits of this bonded structure B was measured using a multimeter immediately after connection and after holding for 240 hours in a constant temperature and humidity chamber at 85°C and 85% RH (after high temperature and high humidity test). The resistance value was expressed as an average of 37 resistance points between adjacent circuits.

In addition, immediately after the connection and after the high-temperature, high-humidity test, the adhesive strength of the bonded structure B was measured and evaluated under the same conditions as the above bonded structure A.

Table 2 below shows the measurement results of the connection resistance and adhesive strength (adhesive force) of the bonded structures A and B measured as described above.

(Storage stability test)

The film-like circuit connection adhesives of Examples 1 and 2 and Comparative Examples 1 and 2 were prepared in a gas barrier container (manufactured by Asahi Kasei Pax Co., Ltd., trade name: Polyplex Bag Hiryu, model number: N-9, material: nylon (thickness: 15 µm)/PE (thickness: 60 µm), size: 200 mm x 300 mm), and then the air in the gas barrier container was removed. Then, after sealing with a heat sealer, it was allowed to stand in a 40°C atmosphere for 48 hours. By leaving it in the above atmosphere, it was set as equivalent to leaving it for 5 months in a -10°C atmosphere. Thereafter, the film-like adhesives for circuit connection of Examples 1 and 2 and Comparative Examples 1 and 2 were mixed between the glass in which the same thin layer of FPC and ITO as described above was formed, and PET in which the thin layer of FPC and Ag paste was formed. It was interposed between the board|substrates, respectively. This was heat-bonded under the same method and conditions as in the case of measuring the above connection resistance and adhesive strength to prepare a bonded structure. The connection resistance and adhesive strength of this bonded structure were measured by the method similar to the above.

The measurement results of the connection resistance and adhesive strength of the bonded structure measured as described above are shown in Table 3 below.

Further, as a result of conducting tests similar to Examples 1 and 2, the bonded structure using the film-like adhesive for circuit connection obtained in Examples 3 to 6 was also found to have good low-temperature curability and storage stability as in Examples 1 and 2. .

The FPC/ITO bonded structure A using the adhesive for circuit connection obtained in Examples 1 to 6 is immediately after connection at a heating temperature of 120°C and 85°C, 85% RH, regardless of whether or not the storage stability test is performed. After holding in a constant temperature and humidity chamber for 240 hours (after high temperature and high humidity test), good connection resistance of 6.8 Ω or less and good adhesive strength of 600 N/m or more were exhibited. Also, for the FPC/Ag bonded structure B, regardless of whether or not the storage stability test was performed, immediately after connection at a heating temperature of 120 ° C. and after holding for 240 hours in a constant temperature and humidity chamber at 85 ° C. and 85% RH. (After the high temperature and high humidity test), a good connection resistance of 1.6 Ω or less and a good adhesive strength of 600 N/m or more were exhibited. It was confirmed that the adhesives for circuit connection obtained in Examples 1 to 6 were excellent in low-temperature curability and storage stability.

In contrast, in the bonded structures using the adhesives for circuit connection obtained in Comparative Examples 1 and 2, when the adhesive for circuit connection before the storage stability test was used, good connection resistance was obtained, but (d) circuit connection of a complex containing boron Since no adhesive was included, it was confirmed that when the adhesive for circuit connection after the storage stability test was used, the connection resistance after holding in a constant temperature and humidity chamber for 240 hours (after the high temperature and high humidity test) was higher than in Examples. In addition, in the bonded structure using the adhesive for circuit connection obtained in Comparative Examples 3 to 4, since the adhesive for circuit connection does not contain (d) a boron-containing complex, even when the storage stability test is not performed, a constant temperature and humidity room It was confirmed that the connection resistance after holding for 240 hours (after the high temperature and high humidity test) increased than in the examples.

10: circuit member (first circuit member)
12: circuit board (first board)
12a: give
14: connection terminal (first connection terminal)
20: circuit member (second circuit member)
22: circuit board (second board)
22a: give
24: connection terminal (second connection terminal)
30, 40: connection member
30a, 40a: adhesive composition
42, 42a: adhesive component
44: conductive particles
100, 200: connection structure of circuit member
300: solar cell module (connection structure)
310a, 310b: solar cell
312 substrate
312a: surface (main surface)
312b: back side (main side)
314 surface electrode
316 back electrode
320: wiring member
330: connection member

Claims (12)

(a) a thermoplastic resin, (b) a radically polymerizable compound, (c) a radical polymerization initiator, and (d) a complex containing boron;
The (d) boron-containing complex is a compound represented by the following general formula (A),
The adhesive composition in which the said (d) complex containing boron contains the amine which has an organic group represented by the following general formula (a1), or the amine which has an organic group represented by the following general formula (a2).

[In Formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or an aryl group, and R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom, Representing an alkyl group having 1 to 18 carbon atoms, an organic group represented by the following general formula (a1), or an organic group represented by the following general formula (a2)]

[In Formula (a1), R ^7a represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ^7b represents a hydrogen atom, an amino group, an alkoxy group, or an alkyl group having 1 to 10 carbon atoms. In addition, s and t each independently represent an integer from 1 to 10]

[In Formula (a2), R ⁸ represents an alkyl group having 1 to 10 carbon atoms. In addition, u represents an integer from 1 to 10] The adhesive composition according to claim 1, wherein the (b) radically polymerizable compound includes a vinyl compound having a phosphoric acid group and radically polymerizable compounds other than the vinyl compound. The method according to claim 1, wherein the (a) thermoplastic resin is a phenoxy resin, a polyurethane resin, a butyral resin, a (meth)acrylic resin, a polyimide resin and a polyamide resin, and a copolymer having a structural unit derived from vinyl acetate. Adhesive composition containing at least 1 sort(s) selected from the group which consists of coalescence. The adhesive composition according to claim 1, wherein the (a) thermoplastic resin contains a polyester urethane resin. The adhesive composition according to claim 1, further comprising (e) conductive particles. The adhesive according to any one of claims 1 to 5, which is used to electrically connect the first connection terminal disposed on the main surface of the first substrate and the second connection terminal disposed on the main surface of the second substrate. composition. The adhesive composition according to any one of claims 1 to 5, which is used in order to electrically connect the connection terminal of a solar cell having the connection terminal disposed on the main surface of the substrate and a wiring member. a first circuit member having a first substrate and a first connecting terminal disposed on a main surface of the first substrate;
a second circuit member having a second substrate and a second connection terminal disposed on a principal surface of the second substrate;
a connection member disposed between the first circuit member and the second circuit member;
The connecting member contains a cured product of the adhesive composition according to any one of claims 1 to 5,
The connection structure in which the said 1st connection terminal and the said 2nd connection terminal are electrically connected. The bonded structure according to claim 8, wherein at least one of the first substrate and the second substrate is made of a substrate made of a thermoplastic resin having a glass transition temperature of 200°C or less. The method according to claim 8, wherein at least one of the first substrate and the second substrate is composed of a substrate containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. connection structure. The method of claim 8, wherein the first substrate is composed of a substrate containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate and polyethylene naphthalate,
The connection structure in which the said 2nd board|substrate is comprised from the base material containing at least 1 sort(s) selected from the group which consists of a polyimide resin and a polyethylene terephthalate. A solar cell having a substrate and connection terminals disposed on a principal surface of the substrate;
a wiring member,
A connection member disposed between the solar cell and the wiring member,
The connecting member contains a cured product of the adhesive composition according to any one of claims 1 to 5,
The connection structure in which the said connection terminal and the said wiring member are electrically connected.

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