JP2019104868A - Adhesive composition for circuit connection and circuit connection structure - Google Patents

Abstract

To provide an adhesive composition for circuit connection that can prevent a circuit connection member from being peeled from a circuit member even when put in a high temperature-high humidity environment.SOLUTION: The present invention provides an adhesive composition for circuit connection containing polyrotaxane.SELECTED DRAWING: None

Description

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

  Heretofore, various adhesive compositions have been used in semiconductor devices and display devices for the purpose of adhering various circuit members in the devices. Such adhesive compositions are required to have various properties such as heat resistance and reliability in high temperature and high humidity conditions in addition to adhesiveness. For example, Patent Document 1 discloses an adhesive composition containing an additive selected according to these required characteristics.

JP, 2013-191625, A

  By the way, according to the study of the present inventors, when the conventional adhesive composition is used, in a high temperature and high humidity environment, between the circuit connection member and the circuit member obtained by curing the adhesive composition. There is a problem that the interaction does not function effectively and the circuit connection member is peeled off from the circuit member.

  Then, this invention makes it a main purpose to provide the adhesive composition for circuit connections which can suppress that a circuit connection member peels from a circuit member, even when exposed to high temperature and high humidity.

  As a result of intensive investigations to achieve the above object, the present inventors improve adhesion characteristics by containing polyrotaxane in the adhesive composition, and suppress peeling even when exposed to high temperature and high humidity. It has been found that the present invention can be completed.

  One aspect of the present invention provides an adhesive composition for circuit connection containing a polyrotaxane. By containing polyrotaxane, the adhesive composition for circuit connection can suppress peeling of the circuit connection member from the circuit member even when exposed to high temperature and high humidity, and has high reliability. The reason why such an effect is exerted is not clear, but the present inventors think as follows. Polyrotaxanes have the property that cyclic molecules can move along linear molecules, as described later. Therefore, the adhesive composition for circuit connection containing polyrotaxane is cured, and the cyclic molecule of polyrotaxane and other components (for example, cyclic molecules of other polyrotaxane, radically polymerizable compound described later, thermoplastic resin, coupling agent, When a crosslinking point is formed (or an interaction (hydrogen bond, covalent bond, etc.) occurs) with the filler, etc.), the crosslinking point moves along the linear molecule, ie, flexibly It may be possible to fluctuate. It is expected that the stress of the circuit connection member is relieved by the flexible change of the cross-linking point. By such an action, breakage at the bridge point of the circuit connection member and stress at the interface between the circuit connection member and the circuit member are less likely to occur, and as a result, even when exposed to high temperature and high humidity, the circuit connection member It is thought that it can control peeling from a circuit member.

  The polyrotaxane may have a reactive functional group. When a polyrotaxane (particularly, a cyclic molecule) has a reactive functional group, it is easy to form a crosslinking point between polyrotaxanes or polyrotaxane and another component (for example, a radically polymerizable compound described later, a thermoplastic resin, etc.) Tend to The reactive functional group may be at least one selected from the group consisting of (meth) acryloyl group, hydroxyl group, epoxy group, and isocyanate group.

  The adhesive composition for circuit connection may further contain a radically polymerizable compound and a radical polymerization initiator.

  The adhesive composition for circuit connection may further contain conductive particles. The content of the conductive particles may be 50% by mass or less based on the total solid content of the adhesive composition other than the conductive particles.

  In order to realize the same stress relaxation performance with a normal thermoplastic component or the like, it is general to add a component that lowers the elastic modulus. However, in that case, there is a trade-off relationship between the holding performance of the conductive particles contained in the adhesive composition for circuit connection and the stress relaxation performance of the circuit connection member. On the other hand, when polyrotaxane is used, when stress is received from the external environment, the stress is temporarily relieved by the flexible change of the crosslinking point, and when stress is removed from the external environment, the cyclic molecule returns to the original state It is estimated to be. As a result, in the high-temperature high-humidity test etc., while suppressing the more excellent peeling, it is expected that the holding performance of the conductive particles will also exhibit the same holding performance as when a normal thermoplastic component etc. is added. Furthermore, it is possible to achieve both the retention performance of the conductive particles that affects the reliability of the connection resistance and the stress relaxation performance of the circuit connection member.

  The adhesive composition for circuit connection may further contain a thermoplastic resin.

  The adhesive composition for circuit connection may be formed into a film. In addition, in this specification, the adhesive composition for circuit connection formed in the film form may be called "adhesive film."

  The adhesive composition for circuit connection may have anisotropic conductivity. In the present specification, an adhesive film having anisotropic conductivity may be referred to as an "anisotropic conductive adhesive film".

  The present invention may also relate to the application of the composition containing the polyrotaxane described above as an adhesive for circuit connection, or the application for the production of an adhesive for the circuit connection of a composition containing the polyrotaxane described above.

  In another aspect, the present invention provides a first circuit member having a first circuit electrode formed on a main surface of a first circuit board, and a second circuit electrode on the main surface of a second circuit board Is formed between the first circuit member and the second circuit member, and the second circuit member and the first circuit electrode are disposed to face each other, A circuit connection structure, comprising: a circuit connection member electrically connecting one circuit electrode and a second circuit electrode to each other, wherein the circuit connection member is a cured product of the above-described adhesive composition for circuit connection. I will provide a.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesive composition for circuit connections which can suppress that a circuit connection member peels from a circuit member also when exposed to high temperature and high humidity is provided. Further, according to the present invention, there is provided a circuit connection structure using such an adhesive composition for circuit connection.

It is a schematic cross section which shows one Embodiment of an anisotropically conductive adhesive film. It is a schematic cross section which shows one Embodiment of a circuit connection structure. It is a schematic cross section which shows one Embodiment of the manufacturing method of a circuit connection structure.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as the case may be. However, the present invention is not limited to the following embodiments. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and overlapping descriptions will be appropriately omitted.

  In the present specification, the "adhesive for circuit connection" is interposed between circuit boards having circuit electrodes facing each other, and for bonding the circuit boards so that the circuit electrodes facing each other are electrically connected. It means what is used.

  As used herein, (meth) acrylic acid means acrylic acid or its corresponding methacrylic acid. The same applies to other similar expressions such as (meth) acrylate and (meth) acryloyl group.

[Polyrotaxane]
The adhesive composition for circuit connection of the present embodiment contains a polyrotaxane. Rotaxane is a compound comprising a cyclic molecule, a linear molecule penetrating the molecular ring of the cyclic molecule, and an end group disposed at both ends of the linear molecule to prevent dissociation of the cyclic molecule (clathrate compound ). Polyrotaxane means a rotaxane formed of a large number of constituent molecules (in particular, cyclic molecules). Polyrotaxanes have the property that cyclic molecules can be moved along linear molecules.

  A cyclic molecule is a molecule that can clathrate a linear molecule so as to penetrate within its molecular ring. The cyclic molecule is not particularly limited as long as it is a molecule that can move along the linear molecule. As used herein, "cyclic" of a cyclic molecule means substantially "cyclic". That is, cyclic molecules may not be completely closed as long as they can move along linear molecules.

  Examples of cyclic molecules include cyclodextrins such as α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, dimethyl cyclodextrin, glucosyl cyclodextrin, etc .; crown ethers; derivatives thereof and the like. These can be used singly or in combination of two or more in the polyrotaxane. Among these, cyclic molecules may be cyclodextrins because they are easily available and that many types of terminal groups can be selected.

  The cyclic molecule may have a reactive functional group. When the cyclic molecule has a reactive functional group, a crosslinking point is formed between the polyrotaxanes or polyrotaxane and other components (for example, a radically polymerizable compound described later, a thermoplastic resin, a coupling agent, a filler, etc.) It tends to be easy to do or interact. The reactive functional group is, in particular, a group capable of forming a crosslinking point with polyrotaxane or another component (for example, radically polymerizable group) or a group capable of expressing an interaction (hydrogen bond, covalent bond, etc.) For example, it may be at least one selected from the group consisting of (meth) acryloyl group, hydroxyl group, epoxy group, and isocyanate group, but not limited thereto.

  The linear molecule is not particularly limited as long as it is a linear molecule that can be included in and integrated with a cyclic molecule. In the present specification, “linear” of a linear molecule means substantially “linear”. That is, the linear molecule may have a branched chain as long as the cyclic molecule can move on the linear molecule.

  Examples of linear molecules include polyalkylene glycols such as polyethylene glycol and polypropylene glycol; and polyolefins such as polyethylene, polypropylene, polyisoprene, polyisobutylene and polybutadiene. These can be used singly or in combination of two or more. Among these, the linear molecule may be a polyalkylene glycol.

  The terminal group is not particularly limited as long as it is a group capable of preventing dissociation of a cyclic molecule from a linear molecule. Examples of the terminal group include an adamantane group, a dinitrophenyl group, a trityl group, a cyclodextrin group, an adamantyl group, a trityl group, a fluoresceinyl group, a pyrenyl group, an anthracenyl group and the like. These can be used singly or in combination of two or more. Among these, the terminal group may be an adamantane group because of easy introduction.

  The polyrotaxane can be obtained, for example, according to the methods described in JP-A-2005-154675, JP-A-2009-270119, and WO 2009/145073. In addition, for example, commercially available products such as “CELME (registered trademark) Super Polymer” series (manufactured by Advanced Soft Materials Co., Ltd.) can be used.

  The content of the polyrotaxane is 0.5% by mass or more and 0.8% by mass, based on the total mass of solid components other than the conductive particles of the adhesive composition, from the viewpoint of suppressing further peeling between the circuit connecting member and the circuit member It may be 1.0 mass% or more. The content of the polyrotaxane is 15% by mass or less, 10% by mass or less, or 8% by mass or less based on the total mass of the solid content other than the conductive particles of the adhesive composition from the viewpoint of further reducing connection resistance It is also good.

[Radically polymerizable compound]
The adhesive composition for circuit connection of the present embodiment may further contain a radically polymerizable compound and a radical polymerization initiator described later. The radically polymerizable compound is not particularly limited and may be arbitrary. In addition, a radically polymerizable compound is the concept which does not include the above-mentioned polyrotaxane. The radically polymerizable compound may be either a monomer or an oligomer of the compound described later, or a combination of both.

  The radically polymerizable compound has one or more radically polymerizable groups. As a radically polymerizable group, a vinyl group, an allyl group, a styryl group, an alkenyl group, an alkenylene group, a (meth) acryloyl group, a maleimide group etc. are mentioned, for example. The number of polymerizable groups possessed by the radically polymerizable compound may be 2 or more from the viewpoint of obtaining physical properties (for example, crosslink density etc.) necessary to reduce connection resistance after polymerization, and cure shrinkage during polymerization 10 or less may be sufficient from a viewpoint of suppressing more. In addition, from the viewpoint of maintaining a balance between the crosslink density and the effect shrinkage, the number of polymerizable groups in the above range (2 to 10) is another radical polymerization in which the number of polymerizable groups is outside the above range. You may add and use a sex compound.

  Specific examples of the radically polymerizable compound include (meth) acrylate compounds, maleimide compounds, vinyl ether compounds, allyl compounds, styrene derivatives, acrylamide derivatives, nadiimide derivatives, natural rubber, isoprene rubber, butyl rubber, nitrile rubber, butadiene rubber, styrene Butadiene rubber, acrylonitrile-butadiene rubber, carboxylated nitrile rubber and the like can be mentioned.

  As a (meth) acrylate compound, for example, epoxy (meth) acrylate, (poly) urethane (meth) acrylate, methyl (meth) acrylate, polyether (meth) acrylate, polyester (meth) acrylate, polybutadiene (meth) acrylate, Silicone acrylate, ethyl (meth) acrylate, 2-cyanoethyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n- Hexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, isopropyl (meth) acrylate, hydroxypropyl (meth) acrylate, isobutyl (meth) acrylate, isobornyl ( Ta) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylate, n-lauryl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate , 2- (Meth) acryloyloxyethyl phosphate, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, trimethylolpropane triol (Meth) acrylate, tetramethylol methane tetra (meth) acrylate, polyethylene glycol di (meth) acrylate, polyalkylene glycol di (meth) acrylate, Hexyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Isocyanuric acid modified difunctional (meth) acrylate, isocyanuric acid modified trifunctional (meth) acrylate, tricyclodecanyl acrylate, dimethylol-tricyclodecane diacrylate, 2-hydroxy-1,3-diacryloxypropane, 2,2 -Bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxypolyethoxy) phenyl] propane, 2,2-di (meth) acryloyloxydiethyl phosphate, 2- Examples include (meth) acryloyloxyethyl acid phosphate and the like.

  As a maleimide compound, for example, 1-methyl-2,4-bismaleimide benzene, N, N'-m-phenylenebismaleimide, N, N'-p-phenylenebismaleimide, N, N'-m-toluylene Bismaleimide, N, N'-4,4-biphenylene bismaleimide, N, N'-4,4- (3,3'-dimethyl-biphenylene) bismaleimide, N, N'-4,4- (3, 3'-Dimethyldiphenylmethane) bismaleimide, N, N'-4,4- (3,3'-diethyldiphenylmethane) bismaleimide, N, N'-4,4-diphenylmethane bismaleimide, N, N'-4, 4-diphenylpropane bismaleimide, N, N'-4,4-diphenyl ether bismaleimide, N, N'-3,3-diphenyl sulfone bismaleimide, 2 2-bis (4- (4-maleimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-4-8 (4-maleimidophenoxy) phenyl) propane, 1,1-bis (4- (4- (4- (4-maleimidophenoxy) phenyl) propane) 4-maleimidophenoxy) phenyl) decane, 4,4′-cyclohexylidene-bis (1- (4maleimidophenoxy) -2-cyclohexylbenzene, 2,2′-bis (4- (4-maleimidophenoxy) phenyl) Hexafluoropropane etc. are mentioned.

  Examples of vinyl ether compounds include diethylene glycol divinyl ether, dipropylene glycol divinyl ether, cyclohexane dimethanol divinyl ether, and trimethylolpropane trivinyl ether.

  As the allyl compound, for example, 1,3-diallyl phthalate, 1,2-diallyl phthalate, triallyl isocyanurate and the like can be mentioned.

  The radically polymerizable compound may be a (meth) acrylate compound from the viewpoint of being excellent in curing reaction rate and obtaining good physical properties after curing. The radically polymerizable compound can achieve both cohesion for reducing connection resistance and elongation for improving adhesion, and from the viewpoint of obtaining more excellent adhesion properties, (poly) urethane (meth) It may be an acrylate compound. The radically polymerizable compound is a compound having a high Tg (glass transition point) such as a (meth) acrylate compound having a dicyclopentadiene skeleton, from the viewpoint of further improving the cohesion for reducing the connection resistance. May be

  The radically polymerizable compound maintains the balance between the crosslink density and the effective shrinkage, reduces the connection resistance, and improves the connection reliability, the terminal or side chain of thermoplastic resin such as acrylic resin, phenoxy resin, polyurethane resin, etc. The compound which introduce | transduced polymeric groups, such as a vinyl group, an allyl group, (meth) acryloyl group, etc. (For example, polyurethane (meth) acrylate) may be sufficient. The weight average molecular weight (Mw) of such a radically polymerizable compound may be 3,000 or more, 5,000 or more, or 10,000 or more from the viewpoint of maintaining a balance between the crosslink density and the effect shrinkage. The weight average molecular weight of the radically polymerizable compound may be 1,000,000 or less, 500,000 or less, or 250,000 or less from the viewpoint of compatibility with other components. In addition, a weight average molecular weight says the value measured using the calibration curve by standard polystyrene from a gel permeation chromatograph (GPC) according to the conditions as described in an Example.

  The radically polymerizable compound may contain, as the (meth) acrylate compound, a (meth) acrylate compound having a phosphoric acid ester structure represented by the following general formula (1). In this case, the adhesion strength of the inorganic substance (metal or the like) to the surface is improved, and thus, for example, it is suitable for adhesion between circuit electrodes.

［式中、ｎは１〜３の整数を示し、Ｒは水素原子又はメチル基を示す。］

[In Formula, n shows the integer of 1-3, R shows a hydrogen atom or a methyl group. ]

  The (meth) acrylate compound having a phosphoric acid ester structure is obtained, for example, by reacting phosphoric anhydride and 2-hydroxyethyl (meth) acrylate. Specific examples of the (meth) acrylate compound having a phosphoric acid ester structure include mono (2- (meth) acryloyloxyethyl) acid phosphate, di (2- (meth) acryloyloxyethyl) acid phosphate and the like. .

  The content of the radically polymerizable compound may be 10% by mass or more, based on the total amount of the polyrotaxane and the radically polymerizable compound, from the viewpoint of further reducing the connection resistance. The content of the radically polymerizable compound may be 25% by mass or more, 50% by mass or more, 75% by mass or more, or 90% by mass or more. The content of the radically polymerizable compound is 99.5% by mass or less, 99% by mass or less, or 98% by mass based on the total amount of the polyrotaxane and the radically polymerizable compound from the viewpoint of suppressing further peeling between the circuit connecting member and the circuit member. It may be mass% or less.

[Radical polymerization initiator]
The radical polymerization initiator can be optionally selected from, for example, compounds such as peroxides and azo compounds.

  As a radical polymerization initiator, for example, 1,1,3,3-tetramethylbutylperoxyneodecanoate, di (4-t-butylcyclohexyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate Carbonate, cumyl peroxy neodecanoate, dilauroyl peroxide, 1-cyclohexyl-1-methylethyl peroxy neo decanoate, t-hexyl peroxy neodecanoate, t-butyl peroxy neodecanoate, t-Butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane T-Hexylperoxy-2-ethylhexanoate t-Butylperoxy-2- Tyl hexanoate, t-butyl peroxy neoheptanoate, t-amyl peroxy-2-ethyl hexanoate, di-t-butyl peroxy hexahydroterephthalate, t-amyl peroxy-3,5,5 -Trimethylhexanoate, 3-hydroxy-1,1-dimethylbutyl peroxy neodecanoate, t-amyl peroxy neodecanoate, t-amyl peroxy-2-ethylhexanoate, di (3- Methyl benzoyl) peroxide, dibenzoyl peroxide, di (4-methyl benzoyl) peroxide, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5- Trimethylhexanoate, t-butyl peroxy laurate, 2 ,, -Dimethyl-2,5-di (3-methylbenzoylperoxy) hexane, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di (benzoyl) Organic peroxides such as peroxy) hexane, t-butylperoxybenzoate, dibutylperoxytrimethyl adipate, t-amyl peroxy normal octoate, t-amyl peroxy isononanoate, t-amyl peroxybenzoate, etc. 2 2,2′-azobis-2,4-dimethylvaleronitrile, 1,1′-azobis (1-acetoxy-1-phenylethane), 2,2′-azobisisobutyronitrile, 2,2′-azobis ( 2-Methylbutyronitrile), 4,4'-azobis (4-cyanovaleric acid), Azo compounds such as 1,1′-azobis (1-cyclohexanecarbonitrile) and the like can be mentioned.

  The content of the radical polymerization initiator is 0.1% by mass or more, 0.5% by mass or more, or 1% by mass or more, based on the total mass of the radically polymerizable compound, from the viewpoint of being excellent in rapid curability. It is also good. The content of the radical polymerization initiator may be 50% by mass or less, 25% by mass or less, or 10% by mass or less based on the total mass of the radically polymerizable compound, from the viewpoint of being more excellent in storage stability.

[Conductive particle]
The adhesive composition for circuit connection of the present embodiment may further contain conductive particles. The conductive particles are not particularly limited as long as they are particles having conductivity, and are metal particles composed of a metal such as Au, Ag, Ni, Cu or solder, conductive carbon particles composed of conductive carbon, etc. May be The conductive particles may be coated conductive particles comprising a core comprising nonconductive glass, ceramic, plastic (polystyrene etc.) and the like, and a covering layer comprising the above metal or conductive carbon and coating the core. Among these, coated conductive particles comprising a metal particle formed of a heat-melting metal or a core containing a plastic and a coating layer containing a metal or conductive carbon and covering the core are preferably used. In this case, since it is easy to deform the cured product of the photocurable composition by heating or pressing, when the circuit electrodes are electrically connected, the contact area between the circuit electrode and the conductive particles is increased. The conductivity between the electrodes can be further improved.

  The conductive particles may be insulating coated conductive particles including the above-described metal particles, conductive carbon particles, or coated conductive particles, and an insulating material such as a resin and covering the surface of the particles. Even when the conductive particles are insulating coated conductive particles, even if the content of the conductive particles is large, the surface of the particles is coated with a resin, so that the occurrence of a short circuit due to contact between the conductive particles can be suppressed. The insulation between adjacent circuit electrode circuits can also be improved. The conductive particles can be used alone or in combination of two or more of the various conductive particles described above.

  The average particle diameter of the conductive particles may be 1.0 μm or more, 2.0 μm or more, or 2.5 μm or more from the viewpoint of excellent dispersibility and conductivity. The average particle diameter of the conductive particles may be 50 μm or less, 30 μm or less, or 20 μm or less from the viewpoint of excellent dispersibility and conductivity. In the present specification, the average particle diameter of the conductive particles is the average value of the particle diameter obtained by measuring the particle diameter of 300 arbitrary conductive particles by observation using a scanning electron microscope (SEM) Means

  The content of the conductive particles may be 50% by mass or less based on the total mass of the solid content other than the conductive particles of the adhesive composition, from the viewpoint of easier suppression of a short circuit. The content of the conductive particles may be 40% by mass or less, 30% by mass or less, or 20% by mass or less. The content of the conductive particles may be 0.1% by mass or more based on the total mass of the solid content of the adhesive composition other than the conductive particles, from the viewpoint of being able to further improve the conductivity. The content of the conductive particles may be 0.5% by mass or more, 1% by mass or more, or 2% by mass or more.

[Thermoplastic resin]
The adhesive composition for circuit connection of the present embodiment may further contain a thermoplastic resin. As a thermoplastic resin, 1 type, or 2 or more types of resin chosen from the group which consists of a phenoxy resin, polyester resin, a polyurethane resin, polyester urethane resin, butyral resin, and an acrylic resin is mentioned, for example. The thermoplastic resin may be a phenoxy resin.

  The content of the thermoplastic resin may be 5 to 95% by mass based on the total mass of the adhesive composition. The content of the thermoplastic resin may be 5% by mass or more, 10% by mass or more, or 15% by mass or more. The content of the thermoplastic resin may be 95% by mass or less, 90% by mass or less, or 85% by mass or less.

[Other ingredients]
The adhesive composition for circuit connection of the present embodiment may further contain other components. Other components include, for example, coupling agents, fillers, softeners, accelerators, deterioration inhibitors, coloring agents, flame retardants, thixotropic agents, and the like.

  As a coupling agent, the silane coupling agent which has organic functional groups, such as a (meth) acryloyl group, a mercapto group, an amino group, an imidazole group, a tetraalkoxy titanate derivative, a polydialkyl titanate derivative etc. are mentioned, for example.

  Fillers include, for example, non-conductive fillers (eg, non-conductive particles). The filler may be either an inorganic filler or an organic filler. Examples of the inorganic filler include metal oxide particles such as silica particles, alumina particles, silica-alumina particles, titania particles and zirconia particles; and inorganic particles such as nitride particles. Examples of the organic filler include organic fine particles such as silicone fine particles, methacrylate-butadiene-styrene fine particles, acryl-silicone fine particles, polyamide fine particles, and polyimide fine particles. These microparticles may have a uniform structure or may have a core-shell type structure.

  The content of the other components may be, for example, 0.1 to 50% by mass based on the total mass of the adhesive composition.

  The adhesive composition for circuit connection of the present embodiment may be formed into a film. The adhesive film is, for example, a varnish obtained by adding a solvent such as methyl ethyl ketone as necessary to the adhesive composition for circuit connection, a releasable support such as a fluororesin film, a polyethylene terephthalate film, a release paper, etc. It can apply | coat on top and can obtain by the method of removing a solvent etc. Since the adhesive film is more convenient in terms of handling and the like, the circuit connection structure can be efficiently produced.

  The adhesive composition for circuit connection of the present embodiment may have anisotropic conductivity. The adhesive composition having anisotropic conductivity contains, for example, conductive particles. The adhesive composition having anisotropic conductivity may be an anisotropic conductive adhesive film (adhesive composition formed into a film having anisotropic conductivity).

  FIG. 1 is a schematic cross-sectional view showing an embodiment of an anisotropic conductive adhesive film. As shown in FIG. 1, the anisotropic conductive adhesive film 1 includes an adhesive component 2 formed in a film shape and a plurality of conductive particles 3 dispersed in the adhesive component 2.

  The thickness of the anisotropic conductive adhesive film 1 may be 10 to 50 μm. When the thickness of the anisotropic conductive adhesive film 1 is 10 μm or more, the adhesive composition tends to be sufficiently filled between the circuit electrodes. If the thickness of the anisotropic conductive adhesive film 1 is 50 μm or less, it tends to be easy to secure conduction.

  Hereinafter, an example of the circuit connection structure which connected as an adherend the circuit members which have a circuit electrode formed on the main surface of a circuit board and a circuit board using an anisotropically conductive adhesive film, and its manufacturing method Will be explained.

  FIG. 2 is a schematic cross-sectional view showing an embodiment of a circuit connection structure. The circuit connection structure 10 shown in FIG. 2 is a first circuit member between the first circuit member 4 and the second circuit member 5 facing each other, and the first circuit member 4 and the second circuit member 5. And a circuit connecting member 6 for connecting the fourth and second circuit members 5.

  The first circuit member 4 includes a first circuit board 41 and a first circuit electrode 42 formed on the major surface 41 a of the first circuit board 41. An insulating layer (not shown) may optionally be formed on the main surface 41 a of the first circuit board 41.

  The second circuit member 5 includes a second circuit board 51 and a second circuit electrode 52 formed on the major surface 51 a of the second circuit board 51. In addition, an insulating layer (not shown) may be formed on the main surface 51 a of the second circuit board 51 as the case may be.

  The first circuit member 4 and the second circuit member 5 are not particularly limited as long as they are members on which circuit electrodes requiring electrical connection are formed. Examples of the first circuit board 41 and the second circuit board 51 include semiconductors, glass, inorganic substrates such as ceramics; TCP (Tape Carrier Package), FPC (Flexible Printed Circuit), COF (Chip On Film), etc. Polyimide substrate; a substrate in which an electrode is formed on a film of polycarbonate, polyester, polyether sulfone or the like; a printed wiring board etc. may be used, and these may be a plurality of combinations.

  The circuit connecting member 6 is a cured product of the adhesive composition for circuit connection of the present embodiment, that is, an insulating material 7 which is formed of the anisotropic conductive adhesive film 1 and is a cured product of the adhesive component 2; And conductive particles 3 dispersed in the insulating material 7. The conductive particles 3 are not only between the first circuit electrode 42 and the second circuit electrode 52 facing each other, but also the main surface 41 a of the first circuit board 41 and the main surface 51 a of the second circuit board 51. May be placed between In the circuit connection structure 10, the first circuit electrode 42 and the second circuit electrode 52 are electrically connected via the conductive particles 3. That is, the conductive particles 3 are in contact with both the first circuit electrode 42 and the second circuit electrode 52.

  In the circuit connection structure 10, as described above, the first circuit electrode 42 and the second circuit electrode 52 facing each other are electrically connected via the conductive particles 3. Therefore, the connection resistance between the first circuit electrode 42 and the second circuit electrode 52 is sufficiently reduced. Therefore, the flow of current between the first circuit electrode 42 and the second circuit electrode 52 can be smoothed, and the functions of the first circuit member 4 and the second circuit member 5 can be sufficiently exhibited. It can be done.

  The method for manufacturing a circuit connection structure according to the present embodiment includes, for example, an arrangement step of arranging a pair of circuit members having circuit electrodes and arranged to face each other with an anisotropic conductive adhesive film interposed therebetween. And a pressure bonding step of heating and pressing the pair of circuit members and the anisotropically conductive film in the thickness direction of the anisotropically conductive adhesive film. In the pressure bonding step, by connecting the anisotropically conductive adhesive film and the electrodes, the electrodes are electrically connected to each other through the conductive particles of the anisotropically conductive adhesive film, and the anisotropically conductive adhesive The films bond the substrates together.

  Next, a method of manufacturing the circuit connection structure will be specifically described with reference to FIG. FIG. 3: is a schematic cross section which shows one Embodiment of the manufacturing method of a circuit connection structure.

  First, the first circuit member 4 and the anisotropic conductive adhesive film 1 are prepared (see FIG. 3A).

  Next, the anisotropic conductive adhesive film 1 is disposed on the major surface 41 a of the first circuit member 4. When the anisotropically conductive adhesive film 1 is laminated on a support (not shown), the anisotropically conductive adhesive film 1 side of the laminate is directed to the first circuit member 4. The stack is placed on the first circuit member 4.

  Then, the anisotropic conductive adhesive film 1 is pressed in the directions of arrows A and B in FIG. 3A, and the anisotropic conductive adhesive film 1 is temporarily connected to the first circuit member 4 (FIG. 3 (FIG. b) see). At this time, heating may be performed together with pressurization.

  Subsequently, as shown in FIG. 3 (c), the second circuit electrode 52 is attached to the first circuit member 4 on the anisotropic conductive adhesive film 1 disposed on the first circuit member 4. The second circuit member 5 is further disposed so as to face (that is, with the first circuit electrode 42 and the second circuit electrode 52 being disposed to face each other). When the anisotropically conductive adhesive film 1 is laminated on a support (not shown), the second circuit member 5 is removed onto the anisotropically conductive adhesive film 1 after the support is peeled off. Deploy.

  Then, while heating the anisotropic conductive adhesive film 1, pressure is applied in the directions of arrows A and B in FIG. 3 (c). Thereby, the anisotropic conductive adhesive film 1 is cured, and the main connection is performed. As a result, a circuit connection structure 10 as shown in FIG. 2 is obtained.

  In the circuit connection structure 10 obtained as described above, the conductive particles 3 can be brought into contact with both the first circuit electrode 42 and the second circuit electrode 52 facing each other, and the first circuit The connection resistance between the electrode 42 and the second circuit electrode 52 can be sufficiently reduced.

  Further, by pressurizing while heating the anisotropic conductive adhesive film 1, the adhesive component 2 is cured in a state where the distance between the first circuit electrode 42 and the second circuit electrode 52 is sufficiently reduced. The insulating material 7 is formed, and the first circuit member 4 and the second circuit member 5 are firmly connected via the circuit connection member 6. That is, in the circuit connection structure 10, since the circuit connection member 6 is formed of the cured product of the adhesive composition for circuit connection of the present embodiment, the first circuit member 4 and the second circuit member The adhesive strength of the circuit connecting member 6 to 5 may be sufficiently high. In particular, the circuit connection member 6 can have sufficient adhesive strength under high temperature and high humidity conditions. In addition, in the circuit connection structure 10, a state in which the adhesive strength is sufficiently high can be maintained for a long time. Therefore, in the circuit connection structure 10, the temporal change in the distance between the first circuit electrode 42 and the second circuit electrode 52 is sufficiently suppressed, and the distance between the first circuit electrode 42 and the second circuit electrode 52 is sufficiently reduced. It can be excellent in the long-term reliability of the electrical characteristics.

  In the present embodiment, the circuit connection structure 10 is manufactured using the anisotropic conductive adhesive film 1 which is easy to handle. Therefore, the anisotropic conductive adhesive film 1 can be easily interposed between the first circuit member 4 and the second circuit member 5, and the first circuit member 4 and the second circuit The connection with the member 5 can be easily made.

  Hereinafter, the present invention will be more specifically described by way of examples. However, the present invention is not limited to these examples.

<Synthesis of Polyurethane Acrylate (UA1)>
Poly (1,6-hexanediol carbonate) (trade name: Duranol T5652, manufactured by Asahi Kasei Chemicals Corporation) in a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser having a calcium chloride drying pipe, and a nitrogen gas inlet pipe A number average molecular weight of 1000) 2500 parts by mass (2.50 mol) and isophorone diisocyanate (manufactured by Sigma Aldrich Co.) 666 parts by mass (3.00 mol) were dropped dropwise uniformly over 3 hours. Next, after nitrogen gas was sufficiently introduced into the reaction vessel, the inside of the reaction vessel was heated to 70 to 75 ° C. to cause a reaction. Next, 0.53 parts by mass (4.3 mmol) of hydroquinone monomethyl ether (manufactured by Sigma Aldrich) and 5.53 parts by mass (8.8 mmol) of dibutyltin dilaurate (manufactured by Sigma Aldrich) were added to a reaction vessel. Thereafter, 238 parts by mass (2.05 mol) of 2-hydroxyethyl acrylate (manufactured by Sigma-Aldrich Co.) was added, and the reaction was performed at 70 ° C. for 6 hours in an air atmosphere. This obtained polyurethane acrylate (UA1). The weight average molecular weight (Mw) of the polyurethane acrylate (UA1) was 15,000. The weight average molecular weight was measured from a gel permeation chromatograph (GPC) using a calibration curve with standard polystyrene according to the following conditions.

(Measurement condition)
Device: Tosoh Corp. GPC-8020
Detector: RI-8020 manufactured by Tosoh Corporation
Column: Hitachi Chemical Co., Ltd. Gelpack GLA160S + GLA150S
Sample concentration: 120 mg / 3 mL
Solvent: Tetrahydrofuran Injection volume: 60 μL
Pressure: 2.94 × 10 ⁶ Pa (30 kgf / cm ² )
Flow rate: 1.00 mL / min

<Production of conductive particles>
On the surface of polystyrene particles, a layer made of nickel was formed to have a layer thickness of 0.2 μm. Thus, conductive particles having an average particle diameter of 4 μm and a specific gravity of 2.5 (g / cm ³ ) were obtained.

(Examples 1 to 6 and Comparative Examples 1 and 2)
Preparation of Varnish of Adhesive Composition
The components shown below are mixed in the blending amounts (parts by mass) shown in Table 1, and the above-mentioned conductive particles are further mixed with 5.0% by mass based on the total mass of solid components other than the conductive particles of the adhesive composition. The varnish of the adhesive composition of Examples 1-6 and Comparative Examples 1 and 2 was obtained so that it might become.

(A) Polyrotaxane A1: Celm Super Polymer (trade name: SA3403P, Mw: 1000000, reactive functional group: acryloyl group, manufactured by Advanced Soft Materials Co., Ltd.)
A2: Celm Super Polymer (trade name: SA1313P, Mw: 180000, reactive functional group: acryloyl group, manufactured by Advanced Soft Materials Co., Ltd.)
A3: Celm Super Polymer (trade name: SM3403P, Mw: 1000000, reactive functional group: methacryloyl group, manufactured by Advanced Soft Materials Co., Ltd.)
A4: Celm Super Polymer (trade name: SH3400P, Mw: 700000, reactive functional group: hydroxyl group, manufactured by Advanced Soft Materials Co., Ltd.)
(B) Radically polymerizable compound B1: dicyclopentadiene type diacrylate (trade name: DCP-A, manufactured by Kyoeisha Chemical Co., Ltd.)
B2: Polyurethane acrylate (UA1) synthesized as described above
B3: 2-methacryloyloxyethyl acid phosphate (trade name: light ester P-2M, manufactured by Kyoeisha Chemical Co., Ltd.)
(C) Radical polymerization initiator C1: Benzoyl peroxide (trade name: Niper BMT-K40, manufactured by NOF Corporation)
(D) Thermoplastic resin D1: Bisphenol A type phenoxy resin (trade name: PKHC, manufactured by Union Carbide)
(E) Coupling agent E1: 3-methacryloxypropyl trimethoxysilane (trade name: KBM 503, manufactured by Shin-Etsu Chemical Co., Ltd.)
(F) Filler F1: Silica fine particles (trade name: R104, manufactured by Nippon Aerosil Co., Ltd., average particle size (primary particle size): 12 nm)
(G) Solvent G1: methyl ethyl ketone

<Production of adhesive film>
The varnishes of the adhesive compositions of Examples 1 to 6 and Comparative Examples 1 and 2 were each coated on a 50 μm-thick PET film using a coating apparatus. Subsequently, hot-air drying at 70 ° C. for 3 minutes was performed, and adhesive films of Examples 1 to 6 and Comparative Examples 1 and 2 having a thickness of 10 μm were produced on a PET film.

<Fabrication of circuit connection structure>
A glass substrate with a thin film electrode comprising a thin film electrode (0.12 μm (1200 Å)) made of silicon nitride (SiN _x ) on a glass substrate with 25 μm pitch COF (manufactured by FLEXSEED) via the adhesive film produced. Using a thermocompression bonding apparatus (heating method: Constant heat type, manufactured by Taiyo Kikai Co., Ltd.), heat and pressure are applied at 170 ° C. and 6 MPa for 4 seconds, and connection is made over a width of 1 mm And the circuit connection structure of Examples 1-6 and Comparative Examples 1 and 2 provided with the cured film (circuit connection member) formed of the adhesive film was produced.

<Peeling evaluation>
The connection appearance immediately after connection of the circuit connection structures of the obtained Examples 1 to 6 and Comparative Examples 1 and 2 and the connection appearance after the high temperature and high humidity test were observed using an optical microscope, and peeling evaluation was performed. . Specifically, the area (peeling area) in which peeling occurred at the interface between the glass substrate and the circuit connection portion was measured from the glass substrate with thin film electrode side. The high temperature and high humidity test was performed using a pressure cooker tester (manufactured by Hirayama Seisakusho Co., Ltd.) for 96 hours under the conditions of 121 ° C., 2 atm, and 100% RH. The results are shown in Table 1.

  The circuit connection structure manufactured using the adhesive composition for circuit connection of Examples 1-6 containing polyrotaxane was manufactured using the adhesive composition for circuit connection of Comparative Examples 1 and 2 which does not contain polyrotaxane. It turned out that peeling is suppressed after the PCT test compared with the circuit connection structure. From these results, even when the adhesive composition for circuit connection of the present invention is exposed to high temperature and high humidity, peeling of the cured film (circuit connection member) from the circuit member can be suppressed, and excellent adhesion reliability It was confirmed to have sex.

  DESCRIPTION OF SYMBOLS 1 ... Anisotropic conductive adhesive film, 2 ... adhesive component, 3 ... conductive particle, 4 ... 1st circuit member, 5 ... 2nd circuit member, 6 ... circuit connection member, 7 ... insulating material, 10 ... circuit connection structure, 41 ... first circuit board, 42 ... first circuit electrode, 51 ... second circuit board, 52 ... second circuit electrode.

Claims (10)

  Adhesive composition for circuit connection containing polyrotaxane.   The adhesive composition for circuit connection according to claim 1, wherein the polyrotaxane has a reactive functional group.   The adhesive composition for circuit connection according to claim 2, wherein the reactive functional group is at least one selected from the group consisting of (meth) acryloyl group, hydroxyl group, epoxy group, and isocyanate group.   The adhesive composition for circuit connection according to any one of claims 1 to 3, further comprising a radically polymerizable compound and a radical polymerization initiator.   The adhesive composition for circuit connection according to any one of claims 1 to 4, further comprising conductive particles.   The adhesive composition for circuit connection according to claim 5, wherein the content of the conductive particles is 50% by mass or less based on the total mass of the solid content of the adhesive composition other than the conductive particles.   The adhesive composition for circuit connection according to any one of claims 1 to 6, further comprising a thermoplastic resin.   The adhesive composition for circuit connection as described in any one of Claims 1-7 formed in the film form.   The adhesive composition for circuit connection as described in any one of Claims 1-8 which has anisotropic conductivity. A first circuit member having a first circuit electrode formed on the main surface of the first circuit board;
A second circuit member in which a second circuit electrode is formed on the main surface of the second circuit board, and the second circuit electrode and the first circuit electrode are disposed to face each other;
A circuit connecting member disposed between the first circuit member and the second circuit member and electrically connecting the first circuit electrode and the second circuit electrode to each other;
Equipped with
The circuit connection structure which is a hardened | cured material of the adhesive composition for circuit connections as described in any one of Claims 1-9.

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