WO2016171253A1

WO2016171253A1 - Adhesive composition and connected structure

Info

Publication number: WO2016171253A1
Application number: PCT/JP2016/062766
Authority: WO
Inventors: 伊澤　弘行; 智樹森尻; 立澤　貴
Original assignee: 日立化成株式会社
Priority date: 2015-04-23
Filing date: 2016-04-22
Publication date: 2016-10-27
Also published as: CN107429143A; KR102490406B1; CN107429143B; JPWO2016171253A1; JP6834946B2; KR20170139505A; TWI705117B; TW201704433A

Abstract

An adhesive composition which contains (a) a thermoplastic resin, (b) a radically polymerizable compound, (c) a radical polymerization initiator and (d) a complex containing boron, and wherein (d) the complex containing boron is a compound represented by general formula (A). (In formula (A), each of R¹, R² and R³ independently represents a hydrogen atom, an alkyl group having 1-18 carbon atoms or an aryl group; and each of R⁴, R⁵ and R⁶ independently represents a hydrogen atom or a specific organic group.)

Description

Adhesive composition and connection structure

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

In a semiconductor element and a liquid crystal display element, various adhesives are conventionally used for the purpose of bonding various members in the element. There are various requirements for adhesives such as adhesiveness, heat resistance, reliability in high temperature and high humidity conditions, and the like. The adhesive is a connection between a liquid crystal display element and TCP (or COF), a connection between FPC and TCP (or COF), a connection between TCP (or COF) and a printed wiring board, and a connection between FPC and a printed wiring board. Etc. are used. The adhesive is also used when a semiconductor element is mounted 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), as well as copper and aluminum. Metal, or ITO (complex oxide of indium and tin), IZO (complex oxide of indium and zinc), AZO (composite oxide of zinc and aluminum), SiN (silicon nitride), SiO ₂ (dioxide dioxide) Substrates having a wide variety of surface states such as silicon) are used. Therefore, it is necessary to design the molecular composition of the adhesive composition according to each adherend.

Recently, with the high integration of semiconductor elements or the high definition of liquid crystal display elements, the pitch between elements and the pitch between wirings are becoming narrower. In addition, a semiconductor element, a liquid crystal display element, or a touch panel using an organic base material having low heat resistance such as PET, PC, or PEN is used. In the adhesive composition applied to such semiconductor elements and the like, the heating temperature at the time of curing is high, and when the curing speed is slow, not only the desired connection portion but also the peripheral member is excessively heated and the peripheral member is damaged. Tend to be a factor. Therefore, adhesion by low temperature curing is required for the adhesive composition.

Conventionally, as an adhesive for the semiconductor element or the liquid crystal display element, a thermosetting resin using an epoxy resin having high adhesiveness and high reliability has been used (for example, see Patent Document 1 below). ). As a constituent component of the resin, an epoxy resin, a curing agent that is reactive with the epoxy resin (such as a phenol resin), a thermal latent catalyst that promotes a reaction between the epoxy resin and the curing agent, and the like are generally used. A thermal latent catalyst is a substance that does not react at a storage temperature such as room temperature and exhibits high reactivity upon heating, and is an important factor that determines the curing temperature and the curing rate. Various compounds have been used from the viewpoints of storage stability at room temperature and curing rate during heating. In the actual process, the 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-mentioned adhesive at a low temperature, it is necessary to use a thermal latent catalyst having a low activation energy, but it is very difficult to combine storage stability.

Recently, a radical curable adhesive using a radical polymerizable compound such as an acrylate derivative or a methacrylate derivative in combination with a peroxide as a radical polymerization initiator has attracted attention. Radical curing can be cured in a short time because radicals that are reactive species are rich in reactivity (see, for example, Patent Document 2 below). In such a radical curable adhesive, a method in which benzoyl peroxide (BPO), an amine compound, an organic boron compound, or the like is used in combination as a radical polymerization initiator has been proposed (for example, see Patent Document 3 below).

Japanese Patent Laid-Open No. 1-113480 International Publication No. 98/44067 JP 2000-290121 A

In order to cure the above-mentioned radical curable adhesive at a low temperature, it is necessary to use a radical polymerization initiator. However, in the conventional radical curable adhesive, it is very important to combine low temperature curable property and storage stability. It is difficult. For example, when the above-described benzoyl peroxide (BPO), amine compound, organoboron compound or the like is used as a radical polymerization initiator of a radical polymerizable compound such as an acrylate derivative or a methacrylate derivative, room temperature (25 ° C., below (Similarly), since the curing reaction proceeds, the storage stability may decrease.

Therefore, an object of the present invention is to provide an adhesive composition having excellent low-temperature curability and storage stability. Moreover, an object of this invention is to provide the connection structure using such an adhesive composition.

As a result of intensive studies to solve the above problems, the present inventors can obtain excellent low-temperature curability and storage stability by using a specific complex containing boron as a constituent component of the adhesive composition. As a result, the present invention has been completed.

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

[In the 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 each independently represent A hydrogen atom, 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) is shown. ]

[In the 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. S and t each independently represent an integer of 1 to 10. ]

[In the formula (a2), R ⁸ represents an alkyl group having 1 to 10 carbon atoms. U represents an integer of 1 to 10. ]

In the present invention, since the adhesive composition contains (d) a complex containing boron, (c) decomposition of the radical polymerization initiator at a low temperature (for example, 80 to 120 ° C.) can be promoted. The low temperature curability of the adhesive composition is excellent. In the present invention, the (d) boron-containing complex is a compound represented by the general formula (A), so that the storage stability of the adhesive composition (for example, around room temperature (for example, −20 to The storage stability at 25 ° C.) is excellent, and even when the adhesive composition is stored for a long period of time, excellent adhesive strength and connection resistance (for example, adhesive strength in a connection structure of a circuit member or a solar cell module) Connection resistance). As described above, the adhesive composition according to the present invention is excellent in low-temperature curability and storage stability.

Furthermore, in the present invention, excellent adhesive strength and connection resistance can be obtained regardless of whether the adhesive composition is stored for a long period of time. In addition, in the present invention, stable performance (adhesive strength and connection resistance) is maintained even after a long-term reliability test (high temperature and high humidity test) regardless of whether the adhesive composition is stored for a long period of time. Can do.

In the adhesive composition according to the present invention, the (b) radical polymerizable compound may contain a vinyl compound having a phosphate group and a radical polymerizable compound other than the vinyl compound. In this case, adhesion by low-temperature curing is facilitated, and the adhesion strength with the substrate having the connection terminals can be further improved.

The thermoplastic resin (a) is composed of a phenoxy resin, polyurethane resin, polyester urethane resin, butyral resin, (meth) acrylic resin, polyimide resin and polyamide resin, and a copolymer having a structural unit derived from vinyl acetate. It may contain at least one selected from the group. In this case, heat resistance and adhesiveness are further improved, and these excellent characteristics can be easily maintained even after a long-term reliability test (high temperature and high humidity test).

The adhesive composition according to the present invention may further contain (e) conductive particles. In this case, since favorable electroconductivity or anisotropic conductivity can be provided to the adhesive composition, it can be more suitably used for bonding between circuit members having connection terminals or for a solar cell module. Become. Moreover, the connection resistance of the connection structure obtained by electrical connection through the adhesive composition can be further sufficiently reduced.

Further, the present inventor has found that the adhesive composition is useful for connecting a member having a connection terminal. The adhesive composition according to the present invention electrically connects 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. It may be used to connect to the solar cell, and may be used to electrically connect the connection terminal of the solar battery cell having the connection terminal disposed on the main surface of the substrate and the wiring member.

A connection structure according to one aspect of the present invention includes a first circuit member having a first connection terminal disposed on a main surface of the first substrate and the first substrate, a second substrate, and the second substrate. A second circuit member having a second connection terminal disposed on the main surface of the second substrate, and a connection member disposed between the first circuit member and the second circuit member, A connection member contains the hardened | cured material of the said adhesive composition, and the 1st connection terminal and the 2nd connection terminal are electrically connected. In the connection structure according to one aspect of the present invention, when the connection member contains the cured product of the adhesive composition, connection resistance and adhesive strength in the connection structure can be improved.

In the connection structure according to one aspect of the present invention, at least one of the first substrate and the second substrate may be composed of a base material including a thermoplastic resin having a glass transition temperature of 200 ° C. or lower. In this case, the adhesive strength in the connection 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 composed of a base material including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. It may be. In this case, even when the first circuit member or the second circuit member having a substrate composed of the specific material (material having low heat resistance) is used, the adhesive composition according to the present invention is used. Since low temperature curing is possible by using, thermal damage to the first circuit member or the second circuit member can be reduced. Further, the wettability between the substrate composed of the specific material and the adhesive composition can be improved, and the adhesive strength can be further improved. As a result, excellent connection reliability can be obtained in the case where a substrate made of the specific material is used.

In the connection structure according to one aspect of the present invention, the first substrate is composed of a base material including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate, and the second substrate is Further, it may be configured by a base material including at least one selected from the group consisting of polyimide resin and polyethylene terephthalate. In this case, even when the first circuit member or the second circuit member having the substrate made of the specific material is used, low temperature curing can be achieved by using the adhesive composition according to the present invention. Since it is possible, thermal damage to the first circuit member or the second circuit member can be reduced. Further, the wettability between the substrate composed of the specific material and the adhesive composition can be improved, and the adhesive strength can be further improved. As a result, excellent connection reliability can be obtained in the case where a substrate made of the specific material is used.

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

According to the present invention, an adhesive composition excellent in low-temperature curability and storage stability can be provided. Such an adhesive composition can improve storage stability compared with the case where the alkyl boron compound of the said patent document 3 is used. Moreover, the adhesive composition according to the present invention is excellent in the balance between low-temperature curability 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. Furthermore, in the adhesive composition according to the present invention, excellent adhesive strength and connection resistance can be obtained regardless of whether the adhesive composition is stored for a long period of time. Moreover, in the adhesive composition according to the present invention, stable performance (adhesive strength and connection) 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 period of time. Resistance) can be maintained. The present invention can provide a connection structure using such an adhesive composition.

It is a schematic cross section which shows the connection structure which concerns on 1st Embodiment of this invention. It is a schematic cross section which shows the manufacturing method of the connection structure shown in FIG. It is a schematic cross section which shows the connection structure which concerns on 2nd Embodiment of this invention. It is a schematic cross section which shows the manufacturing method of the connection structure shown in FIG. It is a schematic cross section which shows the connection structure which concerns on 3rd Embodiment of this 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, “(meth) acrylate” means acrylate and methacrylate corresponding thereto, and “(( “Meth) acrylic resin” means an acrylic resin and a corresponding methacrylic resin, “(meth) acryloyl group” means an acryloyl group and a corresponding methacryloyl group, and “(meth) acryloyloxy group”. Means an acryloyloxy group and a corresponding methacryloyloxy group.

Moreover, in this specification, "weight average molecular weight" means the value measured by the gel permeation chromatograph (GPC) using the calibration curve by a standard polystyrene according to the conditions shown below.
(Measurement condition)
Equipment: 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: 120mg / 3ml
Solvent: Tetrahydrofuran Injection volume: 60 μl
Pressure: 30 kgf / cm ²
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. ing.

((A) thermoplastic resin)
(A) A thermoplastic resin is a resin that has a property of being able to repeat this process in a liquid state with a high viscosity by heating, being deformed freely by external force, and being hardened while maintaining its shape when cooled and removed. (Polymer). 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 further preferably −20 ° C. or higher. (A) The glass transition temperature of the thermoplastic resin is preferably 190 ° C or lower, more preferably 170 ° C or lower, still more preferably 150 ° C or lower, particularly preferably 130 ° C or lower, and extremely preferably 110 ° C or lower.

(A) The thermoplastic resin includes, for example, phenoxy resin, polyurethane resin, polyester urethane resin, butyral resin (for example, polyvinyl butyral resin), (meth) acrylic resin, polyimide resin and polyamide resin, and structural units derived from vinyl acetate. It can contain at least one selected from the group consisting of a copolymer (vinyl acetate copolymer such as ethylene-vinyl acetate copolymer). These can be used individually by 1 type or in mixture of 2 or more types. Furthermore, these (a) thermoplastic resins may contain a siloxane bond or a fluorine substituent. These are preferably in a state in which the resins to be mixed are completely compatible with each other, 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 the film-forming property is obtained, and the fluidity as the film-like adhesive composition. A wide range of melt viscosities affecting the viscosity. (A) The weight average molecular weight of the thermoplastic resin is preferably 5000 or more, more preferably 7000 or more, further preferably 10,000 or more, particularly preferably 20000 or more, and extremely preferably 25000 or more. (A) If the weight average molecular weight of the thermoplastic resin is 5000 or more, good film formability tends to be obtained. (A) The weight average molecular weight of the thermoplastic resin is preferably 150,000 or less, more preferably 100,000 or less, still more preferably 80000 or less, particularly preferably 70000 or less, and extremely preferably 65000 or less. (A) When the weight average molecular weight of the thermoplastic resin is 150,000 or less, good compatibility with other components tends to be easily obtained.

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

((B) Radical polymerizable compound)
(B) A radically polymerizable compound refers to a compound that generates 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, for example, a compound having a functional group (vinyl group, (meth) acryloyl group, allyl group, maleimide group, etc.) that is polymerized by an active radical can be suitably used.

(B) Specific examples of the radical polymerizable compound include oligomers such as epoxy (meth) acrylate oligomers, urethane (meth) acrylate oligomers, polyether (meth) acrylate oligomers, and polyester (meth) acrylate oligomers; trimethylolpropane Poly (ethylene 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; bisphenoxy Tanol fluorene (meth) acrylate; epoxy (meth) acrylate with bisphenol fluorenediglycidyl ether added with (meth) acrylic acid; bisphenol fluorenediglycidyl ether with glycidyl group added with ethylene glycol or propylene glycol And compounds having a (meth) acryloyloxy group introduced therein; compounds represented by the following general formula (B) or general formula (C), and the like.

[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 represents an integer of 0 to 8. ]

In addition, (b) the radical polymerizable compound may be a compound that exhibits a solid state without fluidity, such as waxy, crystalline, glassy, powdery, when left alone at 30 ° C. It can be used without any particular limitation. Specific examples of such (b) radical polymerizable compounds include N, N′-methylenebisacrylamide, diacetone acrylamide (also known as diacetone acrylamide), N-methylol acrylamide, N-phenyl methacrylamide, 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'-Dife Lumethane bismaleimide, m-phenylene bismaleimide, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, N-methacryloxy Maleimide, N-acryloxymaleimide, 1,6-bismaleimide- (2,2,4-trimethyl) hexane, N-methacryloyloxysuccinimide, N-acryloyloxysuccinimide, 2-naphthyl methacrylate, 2-naphthyl Acrylate, pentaerythritol tetraacrylate, divinylethyleneurea, divinylpropyleneurea, 2-polystyrylethyl methacrylate, N-phenyl-N '-(3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine, N-pheny -N '-(3-acryloyloxy-2-hydroxypropyl) -p-phenylenediamine, tetramethylpiperidyl methacrylate, tetramethylpiperidyl acrylate, pentamethylpiperidyl methacrylate, pentamethylpiperidyl acrylate, octadecyl acrylate, Nt-butylacrylamide N- (hydroxymethyl) acrylamide, compounds represented by the following formulas (D) to (M), and the like.

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

[In the 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 represents a hydrogen atom or a methyl group, and g represents an integer of 15 to 30. ]

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

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

Moreover, urethane (meth) acrylate can be used as the (b) radical polymerizable compound. Urethane (meth) acrylate may be used independently and 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) a radical polymerizable compound other than urethane (meth) acrylate, flexibility is improved and adhesive strength can be further improved.

Urethane (meth) acrylate is not particularly limited, but urethane (meth) acrylate represented by the following general formula (N) is preferable. Here, urethane (meth) acrylate represented by the following general formula (N) includes aliphatic diisocyanate or alicyclic diisocyanate, aliphatic ester diol, alicyclic ester diol, and aliphatic carbonate diol. And a condensation reaction with at least one selected from the group consisting of alicyclic 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, and R ²⁶ represents a saturated aliphatic group or a saturated alicyclic group. , R ²⁷ 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-methylpentane-1, 5-diisocyanate, 2,2,4-trimethylhexamethylene-1,6-diisocyanate, 2,4,4-trimethylhexamethylene-1,6-diisocyanate, isophorone diisocyanate, cyclohexyl diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated It may be selected from diphenylmethane diisocyanate, hydrogenated trimethylxylylene diisocyanate, and the like.

The aliphatic ester diol or alicyclic ester diol constituting the urethane (meth) acrylate is ethylene glycol, propylene glycol (also known as 1,2-propanediol), 1,3-propanediol, 1, 3-butanediol, 1,4-butanediol, neopentyl glycol, 1,2-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 2-methyl-2, 4-pentanediol, 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- Methyl-2,5-hexanediol, 1,2-octanediol, 1,8-octanediol, 1,7-heptanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol , Saturated or unsaturated such as dodecanediol (1,12-dodecanediol, etc.), pinacol, 1,4-butynediol, triethylene glycol, diethylene glycol, dipropylene glycol, cyclohexanedimethanol, 1,4-cyclohexanedimethanol, etc. Low molecular weight glycols; adipic acid, 3-methyladipic acid, 2,2,5,5-tetramethyladipic acid, maleic acid, fumaric acid, succinic acid, 2,2-dimethylsuccinic acid, 2-ethyl-2- Methyl succinic acid, 2,3-dimethyl succinic acid, oxalic acid, malonic acid, methyl malo Acid, ethylmalonic acid, butylmalonic acid, dimethylmalonic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 2,4-dimethyl Polyester diols obtained by dehydration condensation of dibasic acids such as glutaric acid, pimelic acid, suberic acid, azelaic acid and sebacic acid or their corresponding acid anhydrides; ring-opening polymerization of cyclic ester compounds such as ε-caprolactone It may be selected from polyester diols obtained in this way. Each of the aliphatic ester-based diol and the alicyclic ester-based diol can be used alone or in combination of two or more.

The aliphatic carbonate-based diol or alicyclic carbonate-based diol constituting the urethane (meth) acrylate may be selected from polycarbonate diols obtained by reaction of at least one kind of the above-described glycols with phosgene. 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.

The urethane (meth) acrylate can be preferably used by adjusting the weight average molecular weight freely within the range of 5000 or more and less than 30000 from the viewpoint of further improving the adhesive strength. If the weight average molecular weight of the urethane (meth) acrylate is within the above range, both flexibility and cohesion can be obtained sufficiently, and the adhesive strength with organic substrates such as PET, PC, PEN and the like is further improved. In addition, further excellent connection reliability can be obtained. Further, from the viewpoint of obtaining such effects more sufficiently, the weight average molecular weight of the urethane (meth) acrylate is more preferably 8000 or more and less than 25,000, further preferably 10,000 or more and less than 25,000, and particularly preferably 10,000 or more and less than 20,000. When the weight average molecular weight is 5000 or more, sufficient flexibility tends to be obtained, and when the weight average molecular weight is less than 30000, the fluidity of the adhesive composition is suppressed from decreasing. There is a tendency to.

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

(B) The radical polymerizable compound may contain at least one kind of a phosphate group-containing vinyl compound (a vinyl compound having a phosphate group) and a radical polymerizable compound other than the phosphate group-containing vinyl compound. Good. (B) The radical polymerizable compound includes an N-vinyl compound selected from the group consisting of an N-vinyl compound and an N, N-dialkylvinyl compound, and a radical polymerizable compound other than the N-vinyl compound, respectively. One or more kinds may be included. By using the phosphoric acid group-containing vinyl compound in combination, the adhesiveness of the adhesive composition to the substrate having connection terminals can be further improved. In addition, the combined use of the N-vinyl compound can improve the crosslinking rate (crosslinking rate) of the adhesive composition.

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

[In the 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 represents an integer of 1 to 8. In formula (O), R ^{28 s} , R ^{29 s} , l s, and m s may be the same or different. ]

[In the formula (P), R ³⁰ represents a (meth) acryloyloxy group, and n, o and p each independently represents an integer of 1 to 8. In the formula (P), R ^{30 s} , n s, o s, and p s 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 represents an integer of 1 to 8. ]

Specific examples of the phosphoric acid group-containing vinyl compound include acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, and acid phosphooxypolyoxy. Propylene 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) acryloyloxyethyl phosphate And vinyl phosphate.

Specific examples of the N-vinyl compound include N-vinylimidazole, N-vinylpyridine, N-vinylpyrrolidone, N-vinylformamide, N-vinylcaprolactam, 4,4′-vinylidenebis (N, N— Dimethylaniline), N-vinylacetamide, N, N-dimethylacrylamide, N, N-diethylacrylamide and the like.

Each of the compounding amounts of the above-mentioned phosphate group-containing vinyl compound and N-vinyl compound is independent of the compounding amount of the radical polymerizable compound other than the phosphate group-containing vinyl compound and N-vinyl compound. Based on the total mass of (the component excluding the conductive particles in the adhesive composition), 0.2% by mass or more is preferable, 0.3% by mass or more is more preferable, 0.5% by mass or more is more preferable, and 1% 0.0 mass% or more is particularly preferable, and 1.5 mass% or more is extremely preferable. There exists a tendency for high adhesive strength to become easy to be obtained as the said compounding quantity is 0.2 mass% or more. Each of the compounding amounts of the above-mentioned phosphate group-containing vinyl compound and N-vinyl compound is preferably 15% by mass or less based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). 10 mass% or less is more preferable, 5 mass% or less is still more preferable, and 3 mass% or less is especially preferable. When the blending amount is 15% by mass or less, the physical properties after curing of the adhesive composition are unlikely to decrease, and reliability tends to be ensured.

The blending amount of the radical polymerizable compound (b) excluding the above-mentioned phosphate group-containing vinyl compound and N-vinyl compound is the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). Is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, particularly preferably 25% by mass or more, and extremely preferably 35% by mass or more. When the blending amount is 5% by mass or more, sufficient heat resistance tends to be easily obtained after curing. The blending amount of the radical polymerizable compound (b) excluding the above-mentioned phosphate group-containing vinyl compound and N-vinyl compound is based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). 95 mass% or less is preferable, 80 mass% or less is more preferable, 70 mass% or less is further more preferable, 60 mass% or less is especially preferable, and 50 mass% or less is very preferable. When the blending amount is 95% by mass or less, when the adhesive composition is used as a film adhesive, good film formability tends to be obtained.

((C) radical polymerization initiator)
(C) As the radical polymerization initiator, compounds that generate radicals by external energy application, such as conventionally known organic peroxides and azo compounds, can be used. (C) The radical polymerization initiator is preferably an organic peroxide having a 1 minute half-life temperature of 90 to 175 ° C. and a weight average molecular weight of 180 to 1000 from the viewpoint of excellent stability, reactivity and compatibility. . When the 1-minute half-life temperature is in this range, the storage stability is further improved, the radical polymerizability is sufficiently high, and the composition can be cured in a short time.

(C) Specific examples of the radical polymerization initiator include 1,1,3,3-tetramethylbutylperoxyneodecanoate, di (4-t-butylcyclohexyl) peroxydicarbonate, di (2 -Ethylhexyl) peroxydicarbonate, cumylperoxyneodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t-hexylperoxyneodecanoate, t-butylper Oxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethyl) Hexanoylperoxy) hexane, t-hexylperoxy-2-ethylhexanoate, t-butylper Xyl-2-ethylhexanoate, t-butylperoxyneoheptanoate, t-amylperoxy-2-ethylhexanoate, di-t-butylperoxyhexahydroterephthalate, t-amylperoxy-3 , 5,5-trimethylhexanoate, 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate, t-amylperoxyneodecanoate, di (3-methylbenzoyl) peroxide, dibenzoylper Oxide, di (4-methylbenzoyl) peroxide, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxide Oxylaurate, 2,5-dimethyl-2,5-di (3-methyl Nzoylperoxy) hexane, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate , Organic peroxides such as dibutyl peroxytrimethyladipate, t-amyl peroxy normal octoate, t-amyl peroxy isononanoate, t-amyl peroxybenzoate; 2,2′-azobis-2,4-dimethyl Valeronitrile, 1,1′-azobis (1-acetoxy-1-phenylethane), 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), dimethyl-2 , 2'-azobisisobutyronitrile, 4,4'-azobis (4-cyanova And azo compounds such as 1,1'-azobis (1-cyclohexanecarbonitrile). These compounds can be used individually by 1 type or in mixture of 2 or more types.

In addition, as the (c) radical polymerization initiator, a compound that generates radicals upon irradiation with light of 150 to 750 nm can be used. Such compounds have high sensitivity to light irradiation, and are described in, for example, Photoinitiation, Photopolymerization, and Photocuring, J. MoI. -P. And α-aminoacetophenone derivatives and phosphine oxide derivatives described in Fouassier, Hanser Publishers (1995, p17-p35). These compounds may be used alone or in combination of two or more, or may be used in combination with the above organic peroxides or azo compounds.

The amount of the radical polymerization initiator (c) is preferably 0.5% by mass or more, preferably 1% by mass or more based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). More preferably, 2% by mass or more is further preferable, 3% by mass or more is particularly preferable, and 5% by mass or more is extremely preferable. When the blending amount is 0.5% by mass or more, the adhesive composition tends to be sufficiently cured. The amount of the radical polymerization initiator (c) is preferably 40% by mass or less, more preferably 30% by mass or less, based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). 20 mass% or less is more preferable, and 10 mass% or less is especially preferable. There exists a tendency for storage stability to fall that the said compounding quantity is 40 mass% or less.

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

Examples of the boron compound contained in the component (d) include alkyldiarylborane, dialkylarylborane, trialkylborane, triarylborane, borohydride and the like. The boron compound is preferably trialkylborane from the viewpoint of further excellent low-temperature curability. The boron compound may be a compound having a plurality of structures of these compounds in the molecule, or a compound having the structure of the above compound 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 linear, branched 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, isopropyl, isobutyl, sec-butyl, tert-butyl, pentyl, 1-ethylpentyl, cyclopentyl, cyclohexyl, isopentyl, heptyl, nonyl, undecyl, tert-octyl Etc. Among these, an ethyl group, an isopropyl group, and an n-butyl group are preferable from the viewpoint of further excellent low-temperature curability. The number of carbon atoms of the alkyl group is preferably from 1 to 12, and more preferably from 1 to 5, from the viewpoint of further excellent low temperature curability. 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 and the like. Among these, a phenyl group, a p-tert-butylphenyl group, and a 4-methylnaphthyl group are preferable, and a phenyl group is more preferable from the viewpoint of further excellent 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.

As the amine compound used as the basic substance of component (d), alkylamine, dialkylamine, trialkylamine, an amine having an organic group represented by general formula (a1), and represented by general formula (a2) Examples include amines having an organic group. Among these, an amine having an organic group represented by the general formula (a1) and an amine having an organic group represented by the general formula (a2) are preferable from the viewpoint of further excellent low-temperature curability and storage stability. . The amine compound may be a compound having a plurality of structures of these compounds in the molecule, or a compound having the structure of the above compound in the main chain and / or side chain of the polymer.

In particular, among the above amine compounds, an amine having an organic group represented by the general formula (a1) is preferable from the viewpoint of further excellent low-temperature curability and storage stability, and the organic group represented by the general formula (a1) is preferable. And an amine having two or more amino groups, more preferably an amine having two or more organic groups represented by formula (a1) in which R ^7a and R ^7b are hydrogen atoms. In this case, the solubility with respect to a thermoplastic resin, a radically polymerizable compound, and a solvent improves, and low temperature curability can further be improved.

As the alkyl group bonded to the nitrogen atom in the amine compound, a linear, branched 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, isopropyl, isobutyl, sec-butyl, tert-butyl, pentyl, 1-ethylpentyl, cyclopentyl, cyclohexyl, isopentyl, heptyl, nonyl, undecyl, tert-octyl Etc. Among these, n-butyl group is preferable from the viewpoint of further excellent low-temperature curability and storage stability. The number of carbon atoms of the alkyl group is preferably 1 to 12 and more preferably 1 to 6 from the viewpoint of further excellent low temperature curability and storage stability.

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

In general formula (a2), R ⁸ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and still more preferably an alkyl group having 1 to 2 carbon atoms. u is preferably an integer of 1 to 5, more preferably an integer of 1 to 3.

Specific examples of the compound represented by the general formula (A) include triethylborane 1,3-diaminopropane, triethylborane N- (2-aminoethyl) ethane-, from the viewpoint of further excellent low temperature curability and storage stability. 1,2-diamine (also known as triethylborane N- (2-aminoethyl) -1,2-ethanediamine), triethylborane 3-methoxy-1-aminepropane (also known as triethylborane 3-methoxypropylamine), tri N-butylborane 3-methoxy-1-aminepropane (also known as tri-n-butylborane 3-methoxypropylamine) and tri-n-butylborane 3-ethoxy-1-aminepropane (also known as tri-n-butylborane) At least one selected from the group consisting of (3-ethoxypropylamine) is preferred.

As the component (d), a combination of a trialkylborane and an amine having an organic group represented by the general formula (a1) or an organic group represented by the general formula (a2) is preferable. When the component (d) is a complex having such a configuration, the low-temperature curability improvement and the storage stability improvement of the adhesive composition can be obtained in a better balance.

As the component (d), specifically, a complex obtained by a conventional synthesis method described in JP-B-7-72264 can be used. For example, when a trialkylborane-amine complex is obtained, a trialkylborane-amine complex can be obtained by adding a tetrahydrofuran (THF) solution containing a trialkylborane to an amine solution.

(D) The component (d) may be used alone or in combination of two or more.

The amount of component (d) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). 1.0 mass% or more 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 promoting the reactivity of the radical polymerization initiator tends to be sufficiently obtained. The blending amount of component (d) is preferably 20% by mass or less, more preferably 15% by mass or less, and more preferably 10% by mass based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). The following is more preferable, and 5% by mass or less is particularly preferable. (D) When the compounding quantity of a component is 20 mass% or less, there exists a tendency for the storage stability of an adhesive composition to become difficult to fall.

((E) conductive particles)
(E) The conductive particles may be particles having conductivity on the whole or on the surface, but when used for connecting members having connection terminals, the average particle diameter is smaller than the distance between the connection terminals. Is preferred.

(E) Examples of the conductive particles include metal particles composed of a metal 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 in which non-conductive glass, ceramic, plastic, or the like is used as a core, and the core is coated with the metal, metal particles, or carbon. Particles obtained by coating the above metal, metal particles or carbon on the core of plastic, and hot-melt metal particles are deformable by heating and pressurization, so that the contact area with the electrode increases at the time of connection and the reliability is improved. Therefore, it is preferable as (e) conductive particles. (E) The electroconductive particle may be a particle obtained by coating silver on a metal particle made of copper, for example. In addition, as the conductive particles (e), a metal powder having a shape in which a large number of fine metal particles are connected in a chain shape as described in JP-A-2005-116291 can be used.

Further, (e) fine particles obtained by further coating the surface of the conductive particles with a polymer resin or the like, or (e) an insulating layer made of an insulating material is provided on the surface of the conductive particles by a method such as hybridization. By using the particles, short-circuiting due to contact between the particles when the blending amount of the conductive particles is increased is suppressed, and insulation between the electrode circuits is improved. Therefore, these particles may be used alone or mixed with (e) conductive particles 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 particle size distribution measuring apparatus (for example, a laser diffraction 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 based on the total volume of the adhesive component (a component excluding the conductive particles in the adhesive composition). 0.2 volume% or more is more preferable, 0.5 volume% or more is further more preferable, and 1 volume% or more is especially preferable. There exists a tendency for electroconductivity to become low that the said compounding quantity is 0.1 volume% or more is 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 (component excluding the conductive particles in the adhesive composition). A volume% or less is more preferable. There exists a tendency for the short circuit of a circuit to become difficult to produce that the said compounding quantity is 30 volume% or less. The “volume%” is determined based on the volume of each component before curing at 23 ° C., but the volume of each component can be converted from weight to volume using specific gravity. Also, do not dissolve or swell the component in a graduated cylinder, etc., put the component into a container containing a suitable solvent (water, alcohol, etc.) that wets the component well, and increase the volume of the component. It can also be determined as a volume.

(Other ingredients)
The adhesive composition according to the present embodiment can contain a stabilizer for controlling the curing rate and for 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; Preferred are aminoxyl derivatives such as 1,6,6-tetramethylpiperidine-1-oxyl and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl; and hindered amine derivatives such as tetramethylpiperidyl methacrylate. 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, based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). 0.02 mass% or more is still more preferable. When the blending amount is 0.005% by mass or more, the curing rate tends to be 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 more preferably 5% by mass or less based on the total mass of the adhesive component (component excluding conductive particles in the adhesive composition). Is more preferable. There exists a tendency for compatibility with another component to fall that the said compounding quantity is 10 mass% or less.

Moreover, the adhesive composition according to the present embodiment may appropriately contain an adhesion aid 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 the formula (R), R ³³ , R ³⁴ and R ³⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or an alkoxycarbonyl group having 1 to 5 carbon atoms. Or R ³⁶ is a (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, ureido group 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 stress relaxation and adhesion improvement. The rubber component refers to a component that exhibits rubber elasticity (JIS K6200) 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. From the viewpoint of improving adhesiveness, a rubber component containing a cyano group or a carboxyl group, which is a highly polar group, in the side chain or terminal is preferable. In addition, even if it has a polybutadiene skeleton, if it exhibits thermoplasticity, it is classified as (a) a thermoplastic resin, and if it exhibits radical polymerizability, it is classified as (b) a radically polymerizable compound.

Specific examples of the rubber component include polyisoprene, polybutadiene, carboxyl-terminated polybutadiene, hydroxyl-terminated polybutadiene, 1,2-polybutadiene, carboxyl-terminated 1,2-polybutadiene, hydroxyl-terminated 1,2-polybutadiene, acrylic rubber, Styrene-butadiene rubber, hydroxyl-terminated styrene-butadiene rubber, acrylonitrile-butadiene rubber, carboxyl group, hydroxyl group, (meth) acryloyl group or morpholino group-terminated acrylonitrile-butadiene rubber, carboxylated nitrile rubber, hydroxyl-terminated poly (oxy) Propylene), alkoxysilyl group-terminated poly (oxypropylene), poly (oxytetramethylene) glycol, polyolefin glycol and the like.

Further, the rubber component having a high polar group and being liquid at room temperature specifically includes a liquid acrylonitrile-butadiene rubber, a liquid having a carboxyl group, a hydroxyl group, a (meth) acryloyl group or a morpholino group at a polymer terminal. Examples include acrylonitrile-butadiene rubber and liquid carboxylated nitrile rubber. The blending amount of acrylonitrile having a polar group is preferably 10 to 60% by mass.

These rubber components can be used singly or in combination of two or more.

Moreover, the adhesive composition according to the present embodiment may contain organic fine particles for the purpose of stress relaxation and adhesion improvement. The average particle size of the organic fine particles is preferably 0.05 to 1.0 μm, for example. In addition, when organic fine particles consist of the above-mentioned rubber component, it classify | categorizes into a rubber component instead of organic fine particles, and when organic fine particles consist of the above-mentioned (a) thermoplastic resin, it is not organic fine particle (a) thermoplastic resin. Classify into:

Specific examples of the organic fine particles include polyisoprene, polybutadiene, carboxyl-terminated polybutadiene, hydroxyl-terminated polybutadiene, 1,2-polybutadiene, carboxyl-terminated 1,2-polybutadiene, acrylic rubber, styrene-butadiene rubber, and acrylonitrile-butadiene. Rubber, carboxyl group, hydroxyl group, acrylonitrile-butadiene rubber having carboxyl group (meth) acryloyl group or morpholino group at the polymer end, carboxylated nitrile rubber, hydroxyl group terminated poly (oxypropylene), alkoxysilyl group terminated poly (oxypropylene), poly (oxypropylene) Oxytetramethylene) glycol, polyolefin glycol, alkyl (meth) acrylate-butadiene-styrene copolymer, alkyl (meth) acrylate-silicone copolymer Silicone - (meth) acrylic copolymer, or organic fine particles comprising composites thereof.

Further, the adhesive composition used for the connection structure described below, 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 silicone fine particles. It may be.

The adhesive composition used for the connection 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 silicone fine particles, thereby causing internal stress. Therefore, the adhesive strength to polyethylene terephthalate, polycarbonate and polyethylene naphthalate can be further improved, and the adhesive strength to a member having a connection terminal can be further improved. In addition, more stable performance can be maintained even after a long-term reliability test.

As the silicone fine particles, fine particles of polyorganosilsesquioxane resin having rubber elasticity are known, and spherical or amorphous silicone fine particles are used. Moreover, it is preferable that a silicone fine particle has a weight average molecular weight of 1 million or more from a viewpoint of a dispersibility and relaxation of an internal stress. The silicone fine particles preferably have a three-dimensional crosslinked structure. Such silicone fine particles have high dispersibility with respect to the resin, and are further excellent in stress relaxation after curing. Since the silicone fine particles having a weight average molecular weight of 1 million or more and / or the silicone fine particles having a three-dimensional cross-linked structure are low in solubility in polymers (thermoplastic resins, etc.), monomers or solvents, the above-mentioned effects Can be obtained more remarkably. Here, “having a three-dimensional crosslinked structure” indicates that the polymer chain has a three-dimensional network structure. The glass transition temperature of the silicone fine particles is preferably from −130 ° C. to −20 ° C., more preferably from −120 ° C. to −40 ° C. Such silicone fine particles can sufficiently relieve the internal stress of the adhesive composition as a circuit connecting material.

Specifically, the silicone fine particles having such a structure include an organopolysiloxane having at least two vinyl groups, an organohydropolyene polysiloxane having at least two hydrogen atoms bonded to silicon atoms, and a platinum catalyst. Fine particles obtained by reaction with (for example, JP-A-62-2579939); organopolysiloxanes having alkenyl groups, organopolysiloxanes having hydrosilyl groups, and platinum-based catalysts (for example, Japanese Patent Laid-Open No. 63-77942); silicone fine particles obtained using diorganosiloxane, monoorganosilsesquioxane, triorganosiloxane and a platinum-based catalyst (for example, Japanese Patent Laid-Open No. 62-270660); methylsilane Triol Beauty / or dropped silicone fine particles obtained by performing the polycondensation reaction (e.g., Patent No. 3,970,453 discloses) in an alkaline aqueous solution of a water / alcohol solution of the partial condensate and the like can be used. In addition, in order to improve dispersibility and adhesion to a substrate, silicone fine particles to which an epoxy compound is added or copolymerized (for example, JP-A-3-167228), silicone to which an acrylate compound is added or copolymerized are added. Fine particles can also be used.

In order to further improve the dispersibility, it is preferable to use silicone fine particles having a core-shell structure. The core-shell type structure has a surface layer (shell layer) having a glass transition temperature higher than the glass transition temperature of the core material (core layer) on the surface of the core material, and is grafted outside the core material (core layer). There is a structure having a layer (shell layer), and silicone fine particles having different compositions in the core layer and the shell layer can be used. Specifically, core-shell type silicone fine particles (for example, Japanese Patent No. 2832143) obtained by adding an alkaline substance or an alkaline aqueous solution and an organotrialkoxysilane to an aqueous dispersion of silicone rubber spherical fine particles, followed by hydrolysis and condensation reaction, WO2009 Core-shell type silicone fine particles as described in JP / A / 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 the molecular terminal or the inner molecular chain can be used. Such silicone fine particles are preferable because dispersibility in a film-forming component and a radical polymerizable substance is improved.

The average particle size of the silicone fine particles is preferably 0.05 to 25 μm, more preferably 0.1 to 20 μm. When the average particle size is 0.05 μm or more, the fluidity of the adhesive composition tends to be suppressed from decreasing due to an increase in surface area. Further, when the average particle size is 25 μm or less, the internal stress tends to be sufficiently relaxed.

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

These silicone fine particles can be used singly or in combination of two or more.

The adhesive composition according to this embodiment can be used in the form of a paste when the adhesive composition is liquid at room temperature. When the adhesive composition is solid at room temperature, it may be heated and used, or may be made into a paste using a solvent. As the solvent that can be used, a solvent that is not reactive with the adhesive composition and the additive and has sufficient solubility is preferable, and a solvent having a boiling point of 50 to 150 ° C. at normal pressure is preferable. When the boiling point is 50 ° C. or higher, volatilization is less likely when left at room temperature, and use in an open system tends to be facilitated. Moreover, when the boiling point is 150 ° C. or lower, it becomes easy to volatilize the solvent, and the reliability after bonding tends to be difficult to decrease.

Also, the adhesive composition according to this embodiment can be formed into a film and used as a film adhesive. The film adhesive which concerns on this embodiment contains the said adhesive composition. If necessary, after applying a solution obtained by adding a solvent or the like to the adhesive composition on a peelable substrate such as a fluororesin film, a polyethylene terephthalate film or a release paper, or on a substrate such as a nonwoven fabric. After impregnating the above solution and placing it on a peelable substrate, the solvent and the like can be removed and used as a film. If it is used in the form of a film, it is more convenient in terms of handleability. According to this embodiment, an 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, and forms, for example, an adhesive layer.

The adhesive composition according to the present embodiment can be bonded by using heating and pressurization together. The heating temperature is preferably 100 to 200 ° C. The pressure is preferably in a range that does not damage the adherend, and generally 0.1 to 10 MPa. These heating and pressurization are preferably performed in the range of 0.5 to 120 seconds, and can be bonded by heating at 120 to 190 ° C., 3 MPa, and 10 seconds.

The adhesive composition according to the present embodiment electrically connects 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. Can be used to connect to each other. Moreover, the adhesive composition according to the present embodiment can be used to electrically connect the connection terminal of the solar battery cell having the connection terminal disposed on the main surface of the substrate and the wiring member. .

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

For example, a first circuit member having a first circuit board and a first circuit member having a first connection terminal disposed on a main surface of the first circuit board, a second circuit board, and a main circuit board of the second circuit board. The second circuit member having the second connection terminal disposed on the surface is arranged such that the first connection terminal and the second connection terminal face each other, and the first connection terminal and the second connection terminal are electrically connected to each other. In a state of being connected, a circuit member connection structure can be configured by arranging the adhesive composition according to the present embodiment or the cured product thereof. In such a case, the adhesive composition according to this embodiment is useful as an adhesive for circuit connection.

<Connection structure>
Next, a connection structure using the above-described adhesive composition and a manufacturing method thereof will be described. According to this embodiment, the first circuit member having the first substrate and the first connection terminal disposed on the main surface of the first substrate, the second substrate, and the second substrate. By curing the adhesive composition in a state in which the adhesive composition is interposed between the second circuit member having the second connection terminal disposed on the main surface, the first connection terminal And the manufacturing method of the connection structure which adhere | attaches a 1st circuit member and a 2nd circuit member in the state which the 2nd connection terminal electrically connected is provided. Moreover, according to the present embodiment, the adhesive in a state where the adhesive composition is interposed between the wiring member and the solar cell having the connection terminal disposed on the main surface of the substrate and the substrate. By curing the composition, a method for manufacturing a connection structure is provided in which the solar cell and the wiring member are bonded in a state where the connection terminal and the wiring member are electrically connected.

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

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

The connecting member 30 is disposed between the circuit member 10 and the circuit member 20. The connecting member 30 connects the circuit member 10 and the circuit member 20 so that the main surface 12a and the main surface 22a face each other substantially in parallel. In the connection structure 100, the connection terminal 14 and the connection terminal 24 are arranged to face each other and are electrically connected by being in contact with each other. The connection member 30 consists of the hardened | cured material of the adhesive composition 30a mentioned later.

The connection structure 100 can be manufactured as follows, for example. First, as shown in FIG. 2, a circuit member 10, a circuit member 20, and an adhesive composition 30a made of the above adhesive composition are prepared. The adhesive composition 30a is formed, for example, by forming the adhesive composition into a film. Next, the adhesive composition 30a is placed on the main surface 22a of the circuit member 20 on which the connection terminals 24 are formed. Then, the circuit member 10 is placed on the adhesive composition 30 a so that the connection terminal 14 faces the connection terminal 24. Subsequently, the adhesive composition 30a is cured while heating the adhesive composition 30a through the circuit member 10 and the circuit member 20, and is pressurized in a direction perpendicular to the

main surfaces

12a and 22a. A connecting member 30 is formed therebetween. Thereby, the connection structure 100 is obtained.

When the adhesive composition contains conductive particles, an anisotropic conductive film prepared using such an adhesive composition is interposed between the opposing connecting terminals and heated and pressed to provide conductivity. A circuit member connection structure can be obtained by bonding the circuit members together while electrically connecting the connection terminals via the particles. FIG. 3 is a schematic cross-sectional view showing the connection structure according to the second embodiment. FIG. 4 is a schematic cross-sectional view showing a manufacturing method of the connection structure shown in FIG. A circuit member connection structure 200 shown in FIG. 3 is obtained by using an adhesive composition containing (e) conductive particles.

3 includes a circuit member 10 and a circuit member 20 similar to the connection structure 100, and a connection member 40. The circuit member connection structure 200 shown in FIG. In the connection structure 200, the connection terminal 14 and the connection terminal 24 are arranged to face each other in a state of being separated from each other.

The connecting member 40 is disposed between the circuit member 10 and the circuit member 20. The connection member 40 is made of 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 is made of a cured product of an adhesive component 42a described later. In the connection structure 200, the conductive particles 44 are in contact with the

connection terminals

14 and 24 between the

connection terminals

14 and 24 that face each other, so that the

connection terminals

14 and 24 are electrically connected to each other via the conductive particles 44. It is connected to the.

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 which consists of the said adhesive composition are prepared. The adhesive composition 40a is formed, for example, by forming the adhesive composition into a film. 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 through the adhesive composition 40a by a method similar to the method of obtaining the circuit member connection structure 100 described above. Thereby, the connection structure 200 is obtained.

At least one of the circuit board 12 and the circuit board 22 in the circuit

member connection structures

100 and 200 may be formed of a base material containing a thermoplastic resin having a glass transition temperature of 200 ° C. or lower. For example, at least one of the circuit board 12 and the circuit board 22 may be composed of an organic base material including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. Thereby, in the case of using an organic base material such as polyethylene terephthalate, polycarbonate, polyethylene naphthalate, and the like, the wettability with the adhesive composition on the circuit board is improved, thereby obtaining excellent adhesive strength even under low temperature curing conditions. be able to. Therefore, stable performance (adhesion strength and connection resistance) can be maintained even after a long-term reliability test (high temperature and high humidity test), and excellent connection reliability can be obtained.

When one of the circuit board 12 and the circuit board 22 is composed of a base material containing at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate, the circuit board 12 And the other circuit board of the circuit boards 22 may be comprised from the base material containing at least 1 sort (s) chosen from the group which consists of a polyimide resin and a polyethylene terephthalate. Thereby, the wettability and adhesive strength with the adhesive composition in the circuit board are further improved, and further excellent connection reliability can be obtained.

The

circuit boards

12 and 22 are made of a base material containing an inorganic substance such as a semiconductor, glass or ceramic; an organic substance such as polyethylene terephthalate, polyethylene naphthalate, polyimide resin or polycarbonate; a composite material such as glass / epoxy resin. It may be. The

circuit boards

12 and 22 may be flexible boards.

FIG. 5 is a schematic cross-sectional view showing the connection structure according to the third embodiment. A 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 disposed on the back surface (main surface) 312b of the substrate 312. And an electrode (connection terminal) 316. The substrate 312 is made of, for example, a semiconductor, an inorganic material such as glass or ceramic, or a composite material such as glass / epoxy resin. 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 battery cell 310a and another member, for example, electrically connecting one solar battery cell and another solar battery cell. In FIG. 5, the surface electrode 314 of the solar battery cell 310 a and the back electrode 316 of the solar battery cell 310 b are electrically connected by the wiring member 320.

The connection member 330 is disposed between the solar battery cell 310a and the wiring member 320, and between the solar battery cell 310b and the wiring member 320, and connects the

solar battery cells

310a and 310b and the wiring member 320. Yes. The connection member 330 contains a cured product of the adhesive composition, and contains an insulating material. The connection member 330 may further contain conductive particles or may not contain conductive particles. When the connection member 330 contains electroconductive particle, the surface electrode 314 and the wiring member 320 of the photovoltaic cell 310a can be electrically connected through electroconductive particle. Further, the back electrode 316 of the solar battery cell 310b and the wiring member 320 can also be electrically connected through the conductive particles. When the connection member 330 does not contain conductive particles, for example, the surface electrode 314 of the solar cell 310 a and / or the back electrode 316 of the solar cell 310 b may be in contact with the wiring member 320.

In the solar cell module 300, the connection member 330 is formed of a cured product of the adhesive composition. Thereby, the adhesive strength of the connection member 330 between the photovoltaic cells 310a and the wiring member 320, and between the photovoltaic cells 310b and the wiring member 320 is sufficiently high, and the connection between the

photovoltaic cells

310a and 310b and the wiring member 320 is achieved. The resistance is small enough. Moreover, even when it is left for a long time in a high temperature and high humidity environment, it is possible to sufficiently suppress a decrease in adhesive strength and an increase in connection resistance. Furthermore, the connection member 330 is a member that can be formed by a heat treatment at a low temperature 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 conventional ones.

The solar cell module 300 uses the

solar cells

310a and 310b and the wiring member 320 in place of the circuit member 10 and the circuit member 20 in the method for manufacturing the

connection structures

100 and 200 described above, and the method for manufacturing the connection structure described above. It can be manufactured by the same method.

In the

connection structures

100 and 200 and the solar cell module 300, the adhesive composition used as a connection member does not need to be completely cured (the highest degree of curing that can be achieved under predetermined curing conditions), and has the above characteristics. As long as this occurs, it may be in a partially cured state.

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)
Polyester urethane resin (trade name: UR-4800, manufactured by Toyobo Co., Ltd., weight average molecular weight: 32000, glass transition temperature: 106 ° C.) is dissolved in a 1: 1 mixed solvent of methyl ethyl ketone and toluene to have a resin content of 30% by mass. A mixed solvent-dissolved product 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.) is dissolved in 60 parts by mass of methyl ethyl ketone, and a solution having a solid content of 40% by mass Prepared.

<Radically polymerizable compound>
(Synthesis of urethane acrylate (UA1))
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser having a calcium chloride drying tube, and a nitrogen gas introduction tube, poly (1,6-hexanediol carbonate) 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 (Sigma Aldrich) 666 parts by mass (3.00 mol) are uniformly added dropwise over 3 hours, and nitrogen gas is sufficiently added to the reaction vessel. After the introduction, the reaction was conducted by heating to 70 to 75 ° C. 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) to the reaction vessel, 2-hydroxyethyl acrylate (manufactured by Sigma Aldrich) 238 parts by mass (2.05 mol) was added and reacted at 70 ° C. for 6 hours in an air atmosphere to obtain urethane acrylate (UA1). The weight average molecular weight of urethane acrylate was 15000.

(Preparation of a vinyl compound having a phosphate group (P-2M))
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 cooler, a thermometer, and a nitrogen gas introduction tube, and 100 ml of 13.1 g (0.13 mol) of triethylboron was added. A solution dissolved in tetrahydrofuran (THF) was added dropwise while maintaining the temperature at about 40 ° C. or lower. After completion of the dropwise addition, the mixture was stirred for about 0.5 hours to obtain triethylborane 1,3-diaminopropane (TEB-DAP).

(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 cooler, a thermometer, and a nitrogen gas inlet tube, and 13.1 g ( A solution prepared by dissolving 0.13 mol) of triethylboron 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, the mixture was stirred for about 0.5 hours to obtain triethylborane N- (2-aminoethyl) ethane-1,2-diamine (TEB-DETA).

(Synthesis of tri-n-butylborane 3-methoxy-1-aminepropane (TnBB-MOPA))
17.8 g (0.20 mol) of 3-methoxy-1-aminepropane was added to a three-necked flask containing a stirrer, a cooler, a thermometer, and a nitrogen gas inlet tube, and 23.7 g (0.13 mol) of tri- A solution prepared by dissolving n-butylboron 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, the mixture was stirred for about 0.5 hours to obtain tri-n-butylborane 3-methoxy-1-aminepropane (TnBB-MOPA).

<Amine compound>
N, N-dimethylaniline (abbreviation: DMA, manufactured by Sigma-Aldrich) was prepared as an amine compound.

<Radical polymerization initiator>
Dilauroyl peroxide (trade name: Parroyl L, manufactured by NOF Corporation) was prepared.

<Conductive particles>
(Preparation of conductive particles)
A nickel layer having a thickness of 0.2 μm is provided on the surface of particles having polystyrene as a core, and then a gold layer having a thickness of 0.02 μm is provided on the outside of the nickel layer. Particles were made.

<Examples 1 to 6 and Comparative Examples 1 to 4>
(Production of adhesive for circuit connection)
As shown in Table 1 in terms of solid mass ratio, a thermoplastic resin, a radical polymerizable compound and a radical polymerization initiator, and a boron-containing complex or amine compound are blended, and further, an adhesive component (in an adhesive for circuit connection) The conductive particles were mixed and dispersed in an amount of 1.5% by volume on the basis of the total volume of the component excluding the conductive particles) to obtain an adhesive for circuit connection. The obtained adhesive for circuit connection is applied on a fluororesin film having a thickness of 80 μm using a coating apparatus, and dried with hot air at 70 ° C. for 10 minutes for connecting a film-like circuit having an adhesive layer thickness of 20 μm. An adhesive was obtained.

(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, and the thickness of the adhesive for film-like circuit connection of Examples 1 to 6 and Comparative Examples 1 to 4; It was interposed between 1.1 mm thick glass (ITO, surface resistance 20Ω / □) formed with a 0.2 μm thin ITO layer. Using a thermocompression bonding apparatus (heating method: constant heat type, manufactured by Toray Engineering Co., Ltd.), it was heated and pressurized at 120 ° C. and 2 MPa for 10 seconds to be connected over a width of 2 mm, and connection structure A (FPC / ITO) Was made. Using a multimeter, the resistance value between adjacent circuits of this connection structure A immediately after connection and after being kept in a constant temperature and humidity chamber at 85 ° C. and 85% RH for 240 hours (after a high temperature and high humidity test) Measured. The resistance value was shown as an average of 37 resistances between adjacent circuits.

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

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

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

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

(Storage stability test)
The adhesives for film-like circuit connection of Examples 1 and 2 and Comparative Examples 1 and 2 were used as gas barrier containers (manufactured by Asahi Kasei Packs Co., Ltd., trade name: Polyflex bag Hiryu, model number: N-9, material: nylon ( After being put in (thickness 15 μm) / PE (thickness 60 μm, size: 200 mm × 300 mm), the air in the gas barrier container was removed. Next, after sealing with a heat sealer, it was left in a 40 ° C. atmosphere for 48 hours. By leaving it in the above atmosphere, it was equivalent to leaving it in a −10 ° C. atmosphere for 5 months. Thereafter, the adhesives for film-like circuit connection of Examples 1 and 2 and Comparative Examples 1 and 2 were used between the same FPC and glass on which a thin layer of ITO was formed, and a thin layer of FPC and Ag paste. And a PET substrate on which each was formed. This was thermocompression-bonded under the same method and conditions as in the measurement of the connection resistance and adhesive strength to produce a connection structure. The connection resistance and adhesive strength of this connection structure were measured by the same method as described above.

Table 3 below shows the measurement results of connection resistance and adhesive strength of the connection structure measured as described above.

Further, the connection structures using the film-like circuit connecting adhesives obtained in Examples 3 to 6 were tested in the same manner as in Examples 1 and 2, and as a result, they were cured at a low temperature as in Examples 1 and 2. And storage stability were good.

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

On the other hand, in the connection structure using the circuit connection adhesive obtained in Comparative Examples 1 and 2, a good connection resistance can be obtained when the circuit connection adhesive before the storage stability test is used. (D) Since the adhesive for circuit connection does not contain a complex containing boron, when the adhesive for circuit connection after the storage stability test is used, after being kept in a constant temperature and humidity chamber for 240 hours ( It was confirmed that the connection resistance after the high-temperature and high-humidity test increased from that of the examples. In addition, in the connection structure using the circuit connection adhesive obtained in Comparative Examples 3 to 4, (d) when the storage stability test is not performed because the complex containing boron does not include the circuit connection adhesive. Even so, it was confirmed that the connection resistance after holding for 240 hours in the constant temperature and humidity chamber (after the high temperature and high humidity test) increased from that of the example.

DESCRIPTION OF SYMBOLS 10 ... Circuit member (1st circuit member), 12 ... Circuit board (1st board | substrate), 12a ... Main surface, 14 ... Connection terminal (1st connection terminal), 20 ... Circuit member (2nd circuit member) ), 22 ... Circuit board (second board), 22a ... Main surface, 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 members, 300 ... solar cell module (connection structure), 310a, 310b ... solar cell, 312 ... substrate, 312a ... surface (main surface) ), 312b ... back surface (main surface), 314 ... front electrode, 316 ... back electrode, 320 ... wiring member, 330 ... connection member.

Claims

(A) a thermoplastic resin, (b) a radical polymerizable compound, (c) a radical polymerization initiator, and (d) a complex containing boron,
(D) The adhesive composition whose complex containing a boron is a compound represented by the following general formula (A).

[In the 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 each independently represent A hydrogen atom, 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) is shown. ]

[In the 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. S and t each independently represent an integer of 1 to 10. ]

[In the formula (a2), R 8 represents an alkyl group having 1 to 10 carbon atoms. U represents an integer of 1 to 10. ]
The adhesive composition according to claim 1, wherein the (b) radical polymerizable compound includes a vinyl compound having a phosphate group and a radical polymerizable compound other than the vinyl compound.
The group (a) wherein the thermoplastic resin is composed of a phenoxy resin, a polyurethane resin, a polyester urethane 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. The adhesive composition of Claim 1 or 2 containing at least 1 sort (s) chosen from more.
(E) The adhesive composition according to any one of claims 1 to 3, further comprising conductive particles.
The first connection terminal disposed on the main surface of the first substrate is used to electrically connect the second connection terminal disposed on the main surface of the second substrate. The adhesive composition according to any one of 1 to 4.
The adhesion according to any one of claims 1 to 4, which is used for electrically connecting the connection terminal of the solar battery cell having the connection terminal disposed on the main surface of the substrate and the wiring member. Agent composition.
A first circuit member having a first substrate and a first connection terminal disposed on a main surface of the first substrate;
A second circuit member having a second connection terminal disposed on the main surface of the second substrate and the second substrate;
A connection member disposed between the first circuit member and the second circuit member;
The connection member contains a cured product of the adhesive composition according to any one of claims 1 to 4,
A connection structure in which the first connection terminal and the second connection terminal are electrically connected.
The connection structure according to claim 7, wherein at least one of the first substrate and the second substrate is formed of a base material including a thermoplastic resin having a glass transition temperature of 200 ° C or lower.
The connection according to claim 7, wherein at least one of the first substrate and the second substrate is composed of a base material including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate, and polyethylene naphthalate. Structure.
The first substrate is composed of a base material including at least one selected from the group consisting of polyethylene terephthalate, polycarbonate and polyethylene naphthalate,
The connection structure according to claim 7, wherein the second substrate is composed of a base material including at least one selected from the group consisting of a polyimide resin and polyethylene terephthalate.
A solar cell having a substrate and connection terminals disposed on the main surface of the substrate;
A wiring member;
A connecting member disposed between the solar cell and the wiring member,
The connection member contains a cured product of the adhesive composition according to any one of claims 1 to 4,
A connection structure in which the connection terminal and the wiring member are electrically connected.