TW202140710A - Adhesive composition, adhesive film, connected structure, and production method therefor - Google Patents

Abstract

An adhesive composition containing a compound which includes an aromatic heterocycle and a side-chain group bonded to the aromatic heterocycle and including at least one chain selected from the group consisting of alkyl chains having three or more carbon atoms and alkylene chains having three or more carbon atoms.

Description

Adhesive composition, adhesive film, connection structure and manufacturing method thereof

The present disclosure relates to an adhesive composition, an adhesive film, a connection structure and a manufacturing method thereof.

In recent years, the miniaturization, thinning, and performance of electronic components have been continuously advanced, and the development of economical high-density mounting technology has been actively carried out. With conventional solder and rubber connectors, it is difficult to connect electronic parts with fine circuit electrodes and circuit members. Therefore, as disclosed in Patent Document 1 to Patent Document 6, a method of connecting an anisotropic conductive adhesive composition with excellent usage resolution and a thin film (adhesive film) thereof is widely used. For example, the following method is known: when the glass of a liquid crystal display (Liquid Cristal Display) is connected to a circuit member such as TAB (Tape Automated Bonding) or FPC (Flexible Print Circuit), one of the conductive particles is contained. The anisotropic conductive adhesive film is sandwiched between the opposed electrodes and heated and pressurized. In this method, the electrodes of the two substrates can be electrically connected to each other while maintaining the insulation between the electrodes adjacent to each other on the same substrate. In this method, an anisotropic conductive adhesive film is used to fix electronic parts and circuit members having fine circuit electrodes.

The above-mentioned connection method is conducive to the weight reduction, thinning and high sensitivity of the module, so it is applied to liquid crystal display devices, electronic paper and other display modules, touch panels and other sensor substrates. For circuit electrodes formed on these substrates, in order to reduce wiring resistance, metal materials including Ag (silver), Cu (copper), Au (gold), Al (aluminum), etc. are used (for example, these metal single or Alloys, etc.). In addition, in recent years, from the viewpoints of price, low surface resistance, and ease of processing, metal materials containing Cu and Ag have been used for the formation of circuit electrodes.

When the anisotropic conductive adhesive composition is used for the connection of the electrode using the metal material containing Cu and Ag, the vicinity of the connection part of the electrode is exposed to the atmosphere, so the electrode is easily affected by oxidation and moisture absorption . In particular, when non-scale copper is used for the electrode, sometimes the adhesive force is reduced and the circuit resistance is increased due to the influence of surface oxidation, and the electrode is sometimes corroded due to the influence of moisture absorption. As a rust inhibitor effective for such metal materials containing Cu and Ag, compounds containing aromatic heterocyclic rings such as benzotriazole are known (for example, Non-Patent Document 1).

[Patent Document 1] Japanese Patent Laid-Open No. 08-148213 [Patent Document 2] Japanese Patent Laid-Open No. 08-124613 [Patent Document 3] Japanese Patent Application Laid-Open No. 11-50032 [Patent Document 4] JP 2011-91044 A [Patent Document 5] JP 2011-100605 A [Patent Document 6] JP 2013-55058 A

[Non-Patent Document 1] Satoshi NAKAGAWA, CiNii Articles, "Effects of Water-soluble Organic Sulfides on the Antirust Effect of Benzotriazole", Report Anticorrosion Technology, Vol.16, No.1

In recent years, the connection area of the connection structure has become smaller due to the higher definition and narrower frame of the module. However, regardless of the connection area, stable connectivity is required. Therefore, the adhesive composition needs to have excellent adhesiveness. However, when the adhesive composition contains a compound containing the above-mentioned aromatic heterocyclic ring, the adhesive force of the adhesive composition may decrease.

Therefore, one of the objectives of the present disclosure is to provide an adhesive composition containing a compound containing an aromatic heterocyclic ring and having excellent adhesion.

One aspect of this disclosure relates to an adhesive composition shown below.

[1] An adhesive composition containing a compound including an aromatic heterocyclic ring and an aromatic heterocyclic ring bonded to the aforementioned aromatic heterocyclic ring and including an alkyl chain having 3 or more carbon atoms and an alkylene group having 3 or more carbon atoms At least one side chain group in the group consisting of chains.

[2] The adhesive composition according to [1], wherein the aromatic heterocyclic ring contains a nitrogen atom as a hetero atom.

[3] The adhesive composition according to [1] or [2], wherein the side chain group includes two or more alkyl chains with 3 or more carbon atoms.

[4] The adhesive composition according to any one of [1] to [3], which further contains conductive particles.

[5] The adhesive composition according to any one of [1] to [4], wherein the total of the non-volatile components contained in the adhesive composition other than conductive particles When it is set to 100 parts by mass, the content of the aforementioned compound is 0.01 to 10 parts by mass.

[6] The adhesive composition according to any one of [1] to [5], which is used to connect circuit members to each other.

Another aspect of the present disclosure relates to an adhesive film having a layer formed of the adhesive composition described in any one of [1] to [6].

In one aspect, the adhesive film may have a multilayer structure of two or more layers. At this time, at least one of the outermost layers of the layers constituting the aforementioned multilayer structure may be a layer formed of the aforementioned adhesive composition. At least one of the layers constituting the multilayer structure may be a layer containing conductive particles.

Another aspect of the present disclosure relates to a connection structure that includes: a first circuit member having a first electrode; a second circuit member having a second electrode; and a circuit connection member disposed on the aforementioned first electrode Between a circuit member and the second circuit member and electrically connect the first electrode and the second electrode to each other, and the circuit connection member includes the adhesive composition described in any one of [1] to [6] Cured matter.

In one aspect, one or both of the first electrode and the second electrode may be formed of a metal material, and the metal material includes at least one selected from the group consisting of Cu and Ag.

Another aspect of the present disclosure relates to a method of manufacturing a connection structure, the manufacturing method comprising: preparing a first circuit member having a first electrode and a second circuit member having a second electrode; The step of arranging the adhesive composition described in any one of [1] to [6] between the second circuit member; and compressing the first circuit member and the second circuit member through the adhesive composition Connect to the step of electrically connecting the first electrode and the second electrode to each other. [Effects of the invention]

According to the present disclosure, it is possible to provide an adhesive composition containing a compound containing an aromatic heterocyclic ring and having excellent adhesion.

Hereinafter, based on the situation, referring to the drawings, the preferred embodiments of the present disclosure will be described. However, this disclosure is not limited to the following embodiments. In addition, in this specification, the numerical range represented by "-" means the range including the numerical value described before and after "-" as the minimum and maximum values, respectively. In addition, the upper limit and the lower limit can be individually described in any combination.

＜Adhesive composition＞ The adhesive composition of one embodiment contains an adhesive component and conductive particles dispersed in the adhesive component.

(Conductive particles) The conductive particles are not particularly limited as long as they are conductive particles, and may be metal particles made of metals such as Au, Ag, Ni, Cu, Pd, solder, and conductive carbon particles made of conductive carbon.

The conductive particles may be coated conductive particles that include a core including non-conductive glass, ceramic, plastic (polystyrene, etc.), etc.; and a coating layer including the above-mentioned metal or conductive carbon and coated with the core. The conductive particles may also be metal particles formed of a hot-melt metal or coated conductive particles, and the coated conductive particles have a core containing plastic and a coating layer containing metal or conductive carbon and coated with the core.

In one embodiment, the conductive particles include a core formed of polymer particles (plastic particles) such as polystyrene and a metal layer covering the core. Regarding the polymer particles, substantially the entire surface of the polymer particles may be covered with a metal layer. Within the scope of maintaining the function as a circuit connection material, a part of the surface of the polymer particles may be exposed without being covered by the metal layer. The polymer particle may be, for example, a particle containing a polymer containing at least one monomer selected from the group consisting of styrene and divinylbenzene as a monomer unit.

The average particle diameter of the polymer particles is, for example, 1 to 40 μm, and from the viewpoint of high-density mounting, it may be 1 to 30 μm. From the viewpoint that the connected state can be maintained more stably even in the case where the surface uniformity of the electrode is uneven (concave and convex on the surface of the electrode, etc.), the average particle size of the polymer particles may be 2-20 μm. The average particle size of the polymer particles may be 1 μm or more or 2 μm or more, or may be 40 μm or less, 30 μm or less, or 20 μm or less.

The metal layer can be formed of various metals such as Ni, Ni/Au, Ni/Pd, Cu, NiB, Ag, and Ru. The metal layer may be an alloy layer formed of an alloy of Ni and Au, an alloy of Ni and Pd, or the like. The metal layer may be a multilayer structure formed by a plurality of metal layers. For example, the metal layer may be formed of a Ni layer and an Au layer. The thickness of the metal layer can be 10 nm or more or 20 nm or more, 500 nm or less or 300 nm or less, or 10 to 500 nm or 20 to 300 nm. The metal layer can be made by electroplating, evaporation, sputtering, etc. The metal layer may be a thin film (for example, a thin film formed by electroplating, evaporation, sputtering, etc.).

From the viewpoint of improving insulation properties, the conductive particles may have an insulating layer. Specifically, for example, an insulating layer covering the coating layer may be provided on the outer side of the coating layer in the conductive particles of the aforementioned embodiment including a core (for example, polymer particles) and a coating layer such as a metal layer covering the core. The insulating layer may be the outermost layer provided on the outermost surface of the conductive particles. The insulating layer may be a layer formed of insulating materials such as silicon dioxide and acrylic resin.

From the viewpoint of excellent dispersibility and conductivity, the average particle diameter of the conductive particles may be 1.0 μm or more, may be 2.0 μm or more, or may be 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 above viewpoint, the average particle diameter of the conductive particles may be 1.0 to 50 μm, may be 2.0 to 30 μm, or may be 2.5 to 20 μm.

It is preferable that the maximum particle size of the conductive particles is smaller than the minimum distance between the electrodes (the shortest distance between adjacent electrodes). From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of the conductive particles may be 1.0 μm or more, may be 2.0 μm or more, or may be 2.5 μm or more. From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of the conductive particles may be 50 μm or less, 30 μm or less, or 20 μm or less. From the above viewpoint, the maximum particle size of the conductive particles may be 1.0 to 50 μm, may be 2.0 to 30 μm, or may be 2.5 to 20 μm.

In this specification, for 300 (pcs) arbitrary particles, the particle size is measured by observing with a scanning electron microscope (SEM), and the average value of the obtained particle size is set as the average particle size, and the obtained The maximum value of is set as the maximum particle size of the particles. In addition, when the shape of the particle is not spherical, such as the case where the particle has protrusions, the particle diameter of the particle is set to the diameter of the circle circumscribing the particle in the SEM image.

The content of conductive particles is determined based on the fineness of the connected electrode, etc. For example, the content of the conductive particles is relative to 100 parts by mass of the adhesive component (that is, when the total of the non-volatile components contained in the adhesive composition except for the conductive particles is 100 parts by mass) It can be 0.1-50 parts by mass. From the viewpoint of insulation and manufacturing cost, the content of the conductive particles may be 0.1 to 30 parts by mass with respect to 100 parts by mass of the adhesive component. The content of the conductive particles may be 0.1 parts by mass or more with respect to 100 parts by mass of the adhesive component, or may be 50 parts by mass or less or 30 parts by mass or less.

(Adhesive ingredients) The adhesive component is defined as a non-volatile component other than the conductive particles in the adhesive composition. Non-volatile components refer to components whose volatilized amount is less than 20% by mass of the whole when heated at 70°C for 10 minutes. For example, when the adhesive composition contains an organic solvent described later, the components other than the organic solvent among the components other than the conductive particles in the adhesive composition are referred to as nonvolatile components. The adhesive component is composed of, for example, an insulating material and has insulating properties as a whole. Adhesive components include at least a compound (hereinafter, also referred to as "aromatic heterocyclic compound A"), the compound including an aromatic heterocyclic ring and an aromatic heterocyclic ring bonded to the aromatic heterocyclic ring and including an alkyl chain selected from the group consisting of 3 or more carbon atoms ( Hereinafter, it is also referred to as a "long-chain alkylene group") and at least one side chain group in the group consisting of an alkylene chain having 3 or more carbon atoms (hereinafter also referred to as a "long-chain alkylene group"). In this specification, the alkyl chain means a monovalent aliphatic saturated hydrocarbon chain, and the alkylene chain means a divalent aliphatic saturated hydrocarbon chain.

In one embodiment, the adhesive component contains a curable component that is cured by heat or light and an aromatic heterocyclic compound A. The curable component includes, for example, a radical polymerizable compound and a free radical generator. Regarding the curable component, it is cured by heat or light to generate a polymer organic component. The adhesive composition containing such an adhesive component has heat or photocurability.

The radical polymerizable compound is a compound containing a functional group polymerized by a radical, and examples thereof include an acrylate compound, a methacrylate compound, and a maleimide compound. Based on the total amount of the adhesive components, the content of the radically polymerizable compound may be, for example, 30% by mass or more, 80% by mass or less, or 30 to 80% by mass.

Examples of acrylate compounds and methacrylate compounds include urethane acrylate, urethane methacrylate, methyl acrylate, ethyl acrylate, isopropyl acrylate, and isobutyl acrylate. , Ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, dimethylol tricyclodecane diacrylate, trimethylolpropane triacrylate, tetramethylolmethane Tetraacrylate, 2-hydroxy-1,3-dipropenyloxypropane, 2,2-bis[4-(propenyloxymethoxy)phenyl]propane, 2,2-bis[4-( Acrylic oxypolyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclodecyl acrylate, bis(acryloxyethyl) isocyanurate, ε-caprolactone modified three (Acrylicoxyethyl) isocyanurate and tris(acryloxyethyl) isocyanurate. These radically polymerizable compounds can be used individually by 1 type or in combination of 2 or more types. From the viewpoint of adhesiveness, the radically polymerizable compound may be urethane acrylate or urethane methacrylate.

As a radically polymerizable compound, from the viewpoint of improving heat resistance, it is possible to use both urethane acrylate or urethane methacrylate and when crosslinked by an organic peroxide compound, the temperature is above 100°C. Free radical polymerizable compound of Tg. Examples of radically polymerizable compounds that independently represent a Tg of 100°C or higher when crosslinked by an organic peroxide compound include compounds containing dicyclopentenyl and/or tricyclodecyl. From the viewpoint that the heat resistance improvement effect can be significantly obtained, the radically polymerizable compound may be a compound containing tricyclodecyl group.

The viscosity of the radically polymerizable compound at 25°C is, for example, 100,000 to 1,000,000 mPa·s, and may also be 100,000 to 500,000 mPa·s. The viscosity of the radically polymerizable compound at 25°C can be 100,000 mPa·s or more, 1,000,000 mPa·s or less or 500,000 mPa·s or less. The viscosity of the radically polymerizable compound at 25°C can be measured using a commercially available E-type viscometer.

The free radical generator is a compound that generates free radicals by decomposition by heat or light, such as a peroxide compound or an azo compound. The free radical generator is preferably selected in accordance with the target connection temperature, connection time, service life, and the like. The free radical generator may be selected from, for example, benzoyl peroxide, diacyl peroxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, and hydroperoxide. One or more compounds in the composition group. From the viewpoint of high reactivity and useful life, the free radical generator may be an organic peroxide compound whose temperature with a half-life of 10 hours is 40° C. or higher and whose temperature with a half-life of 1 minute is 180° C. or lower.

Based on the total amount of the adhesive components, the content of the free radical generator may be 0.05% by mass or more, 15% by mass or less, or 0.05-15% by mass. When the adhesive component contains a free radical generator, the free radical generator can be used in combination with a decomposition accelerator, an inhibitor, and the like.

The adhesive component of this embodiment may also contain a polymerization inhibitor. The polymerization inhibitor may be a hydroquinone compound, a methyl ether hydroquinone compound, or the like. Based on the total amount of the adhesive components, the content of the polymerization inhibitor may be 0.05% by mass or more, may be 5% by mass or less, or may be 0.05 to 5% by mass.

The aromatic heterocyclic compound A is an organic compound containing an aromatic heterocyclic ring and a side chain group bonded to the aromatic heterocyclic ring.

An aromatic heterocyclic ring is defined as an aromatic ring containing one or more heteroatoms (Heteroatom) in the ring, and is composed of carbon atoms and heteroatoms. As a hetero atom, a nitrogen atom, a sulfur atom, and an oxygen atom can be mentioned, for example. In the aromatic heterocycle, the heteroatom functions as a Lewis base on the metal surface constituting the electrode and becomes a ligand. In the case of using the aromatic heterocyclic compound A, the oxidation of the electrode surface is suppressed by the above-mentioned coordination effect. Therefore, the increase in connection resistance can be suppressed and the connection reliability can be improved. From the viewpoint that the strength as a Lewis base is strong and the connection reliability can be further improved, the hetero atom may include a nitrogen atom, a sulfur atom, or an oxygen atom. Among these, there is a tendency that when the hetero atom includes a nitrogen atom, the effect of improving the connection reliability can be significantly obtained. That is, the aromatic heterocyclic ring may be a nitrogen-containing aromatic heterocyclic ring from the viewpoint that the connection reliability can be significantly improved.

The number of heteroatoms contained in the aromatic heterocyclic ring may be 1 or more or 2 or more, or 4 or less, or 1 to 4 or 2 to 4. The aromatic heterocyclic ring may include a plurality of heteroatoms of one type, or may include a plurality of heteroatoms. The aromatic heterocyclic ring may include, for example, a nitrogen atom and an oxygen atom, or may include a nitrogen atom and a sulfur atom, or may include a nitrogen atom, an oxygen atom, and a sulfur atom. When there is one nitrogen atom contained in the aromatic heterocyclic ring, the aromatic heterocyclic ring may include other atoms (sulfur atom, oxygen atom, etc.) in addition to the carbon atom and the nitrogen atom.

The aromatic heterocyclic ring is, for example, a 5-membered ring or a 6-membered ring. From the viewpoint of the effects of the present disclosure, the aromatic heterocyclic ring may be a 5-membered ring. Examples of the 5-membered ring include a pyrazole ring, an imidazole ring, a triazole ring, a tetrazole ring, a thiazole ring, a thiadiazole ring, an azole ring, a pyrrole ring, a furan ring, and a thiophene. Examples of the 6-membered ring include a pyrimidine ring, a pyridine ring, a pyridine ring, a pyridine ring, and a tricyclic ring.

From the viewpoint of suppressing the increase in connection resistance and further improving connection reliability, the aromatic heterocyclic ring may be a pyrazole ring, an imidazole ring, a triazole ring, a tetrazole ring, a thiazole ring, a thiadiazole ring, an azole ring, or a pyrimidine ring. ring. Among these, there is a tendency that if the aromatic heterocyclic ring is a pyrazole ring, an imidazole ring, a triazole ring, a tetrazole ring, a thiazole ring, a thiadiazole ring, or an azole ring, the connection reliability can be significantly obtained Improve results. Among these, there is a tendency that if the aromatic heterocyclic ring is a triazole ring, a tetrazole ring, or a thiadiazole ring, the effect of improving the connection reliability can be more significantly obtained.

The aromatic heterocyclic ring contained in the aromatic heterocyclic compound A may be one or plural. When the aromatic heterocyclic compound A contains a plurality of aromatic heterocyclic rings, the plurality of aromatic heterocyclic rings may be the same as or different from each other. The aromatic heterocyclic ring may be condensed with other rings or not. That is, the aromatic heterocyclic compound A may include a monocyclic ring formed of an aromatic heterocyclic ring, or may include a condensed ring including an aromatic heterocyclic ring. The other ring may be an aromatic heterocyclic ring or an aromatic carbocyclic ring. That is, the aromatic heterocyclic compound A may have a ring other than the aromatic heterocyclic ring, or may not have a ring other than the aromatic heterocyclic ring. From the viewpoint of the effect of the present disclosure, the other ring may be an aromatic carbocyclic ring.

The aromatic carbocyclic ring is an aromatic ring composed only of carbon atoms and hydrogen atoms, and is a ring that does not contain heteroatoms in the ring. As an aromatic carbocyclic ring, a benzene ring can be mentioned, for example. As a condensed ring containing an aromatic carbocyclic ring and an aromatic heterocyclic ring, a benzimidazole ring, a benzotriazole ring, a benzothiazole ring, a benzoxazole ring, etc. are mentioned, for example.

The side chain group may be directly bonded to the aromatic heterocyclic ring. That is, the side chain group may be a substituent substituted with a hydrogen atom bonded to a carbon atom or a heteroatom constituting an aromatic heterocyclic ring. The side chain group may be indirectly bonded to the aromatic heterocyclic ring by directly bonding to a ring other than the aromatic heterocyclic ring (for example, an aromatic carbocyclic ring) in the condensed ring containing the aromatic heterocyclic ring. That is, the side chain group may be a substituent that replaces the hydrogen atom bonded to the carbon atom constituting the ring other than the above-mentioned aromatic heterocyclic ring. From the viewpoint of the effect of the present disclosure, the side chain group may be directly bonded to the heteroatom in the aromatic heterocyclic ring. The number of side chain groups may be one or two or more. The number of side chain groups is 3 or less, for example.

The side chain group includes a long-chain alkyl group and/or a long-chain alkylene group. The side chain group may include a plurality of long-chain alkyl groups, or may include a plurality of long-chain alkylene groups, or may include more than one long-chain alkyl group and more than one long-chain alkylene group. From the viewpoint of more excellent adhesive force, the side chain group may include two or more long-chain alkyl groups. That is, the side chain group may include two or more C3 or more alkyl chains. The number of long-chain alkyl groups is, for example, 3 or less or 2 or less.

The carbon number of the long-chain alkyl group and the long-chain alkylene group is 3 or more, and from the viewpoint of more excellent adhesive force, it may be 4 or more, 5 or more, 6 or more, 7 or more, or 8 or more. From the viewpoint of suppressing the decrease in coordination ability as the steric hindrance increases, the carbon number of the long-chain alkyl group and the long-chain alkylene group may be 30 or less, 20 or less, 15 or less, or 10 or less. From the above viewpoint, the carbon number of the long-chain alkyl group and the long-chain alkylene group is 3-30, for example. The long-chain alkyl group and the long-chain alkylene group may be linear or branched. When the long-chain alkyl group is branched, the carbon number of the main chain of the long-chain alkyl group (the chain with the largest number of consecutive carbons) may be within the above range. Similarly, when the long-chain alkylene is branched, the carbon number of the main chain of the long-chain alkylene (the chain with the largest number of consecutive carbons) may be within the above range.

Specific examples of long-chain alkyl groups include propyl, butyl, pentyl, hexyl, heptyl, octyl, isobutyl, second butyl, isopentyl, neopentyl, and tertiary pentyl. , Isohexyl, etc. Specific examples of long-chain alkylene include trimethylene, butene, tetramethylene, 1-methyltrimethylene, 2-methyltrimethylene, 1,1-dimethylethylene, 1,2-Dimethylethylene, etc.

The side chain group may include functional groups other than the long-chain alkyl group and the long-chain alkylene group. Examples of such functional groups include amino groups, silyl groups (alkoxysilyl groups, alkylsilyl groups, etc.), hydroxyl groups, ester groups, and mercapto groups. From the viewpoint of more excellent adhesive force, the side chain group may include an alkoxysilyl group. Examples of alkoxysilyl groups include methoxysilyl, dimethoxysilyl, trimethoxysilyl, ethoxysilyl, diethoxysilyl, triethyl Oxysilyl, propoxysilyl, butoxysilyl, isopropoxysilyl, etc. The above-mentioned functional group may be a substituent that replaces the hydrogen atom bonded to the carbon atom of the long-chain alkyl group and the long-chain alkylene group. The number of the aforementioned functional groups contained in the side chain group may be one or two or more. The type of the aforementioned functional group contained in the side chain group may be one type or two or more types.

When the side chain group includes an alkoxysilyl group, the radically polymerizable compound may include a functional group that reacts with the alkoxysilyl group to bond. As such a functional group, a hydroxyl group, a carboxyl group, an alkoxysilyl group, etc. are mentioned, for example. When the radically polymerizable compound contains an alkoxysilyl group, the alkoxysilyl group may be the same as or different from the alkoxysilyl group contained in the side chain group.

The side chain group may include a linking group for bonding a long-chain alkyl group and/or a long-chain alkylene group to an aromatic heterocyclic ring. When the side chain group includes a linking group, the linking group is directly bonded to the aromatic heterocyclic ring or the condensed ring including the aromatic heterocyclic ring. The linking group is, for example, a divalent or trivalent group (for example, an organic group) containing heteroatoms such as a nitrogen atom, a sulfur atom, and an oxygen atom. The side chain group may not include a linking group, and may be bonded to an aromatic heterocyclic ring by directly bonding a long-chain alkyl group or a long-chain alkylene group to an aromatic heterocyclic ring or a condensed ring containing an aromatic heterocyclic ring.

The aromatic heterocyclic ring may be substituted with a substituent other than the above-mentioned side chain group. As such a substituent, for example, it may be a hydrocarbon group (except for a long-chain alkyl group or a long-chain alkylene group), or the above-mentioned functional group that may be contained in a side chain group. The hydrocarbon group may be an alkyl group or the like.

From the viewpoint of more excellent adhesion and the viewpoint of suppressing the increase in connection resistance and improving connection reliability, the content of the aromatic heterocyclic compound is relative to 100 parts by mass of the adhesive component (that is, the amount of the When the total of the components other than the conductive particles in the non-volatile components is 100 parts by mass), it can be 0.01 parts by mass or more, 0.1 parts by mass or more, 0.2 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, 2 Parts by mass or more, 3 parts by mass or more, or 4 parts by mass or more. From the viewpoint of better adhesion and from the viewpoint of suppressing the increase in connection resistance and improving connection reliability, the content of the aromatic heterocyclic compound can be 10 parts by mass or less, 8 parts by mass or less, 5 parts by mass or less, or 2 parts by mass or less Or 1 part by mass or less. From the above viewpoint, the content of the aromatic heterocyclic compound relative to 100 parts by mass of the adhesive component may be, for example, 0.01-10 parts by mass, 0.1-8 parts by mass, 0.2-5 parts by mass, 0.5-2 parts by mass, 0.5-1 parts by mass. Parts by mass, 1-10 parts by mass, 2-8 parts by mass, 3-8 parts by mass, 3-5 parts by mass, or 4-5 parts by mass.

In another embodiment, the adhesive component contains a thermosetting resin and the above-mentioned aromatic heterocyclic compound.

Regarding thermosetting resins, for example, epoxy resins, cyanate ester resins, maleimide resins, allyl diimide resins, phenol resins, urea resins, acid alcohol resins, acrylic resins, and unsaturated resins can be cited. Polyester resin, diallyl phthalate resin, silicone resin, resorcinol-formaldehyde resin, xylene resin, furan resin, polyurethane resin, ketone resin, triallyl cyanurate (Triallyl cyanurate) ) Resin, polyisocyanate resin, resin containing tris(2-hydroxyethyl) isocyanurate, resin containing triallyl trimellitate, thermosetting resin synthesized from cyclopentadiene, based on Thermosetting resin for trimerization of aromatic dicyandiamide, etc. These thermosetting resins can be used individually by 1 type or in combination of 2 or more types. Based on the total amount of the adhesive components, the content of the thermosetting resin may be, for example, 20% by mass or more, 50% by mass or less, or 20-50% by mass.

When the adhesive component contains a thermosetting resin, the adhesive component may further contain a curing agent. The curing agent may be, for example, a catalyst type curing agent. The catalyst type curing agent can be hydrazine, boron trifluoride-amine complex, sulfonium salt, aminoimines, diamine maleonitrile, polyamine salt, dicyandiamine, etc., or it can also be For these modified materials. The curing agent may be an addition polymerization curing agent such as polyamine, polythiol, polyphenol, acid anhydride, and the like. As the curing agent, an addition polymerization type curing agent and a catalyst type curing agent can also be used at the same time. A curing agent can be used individually by 1 type or in combination of 2 or more types. Based on the total amount of the adhesive components, the content of the curing agent may be 0.5% by mass or more, 15% by mass or less, or 0.5-15% by mass.

The curing agent may be microencapsulated by coating the curing agent with a polymer compound such as a polyurethane-based or polyester-based polymer, a metal thin film such as Ni, Cu, or an inorganic compound such as calcium silicate. According to this curing agent, the use time can be extended.

In another embodiment, the adhesive component contains the aforementioned radical polymerizable compound, free radical generator, thermosetting resin, and aromatic heterocyclic compound.

In this embodiment, based on the total amount of the adhesive components, the total content of the radical polymerizable compound and the thermosetting resin may be, for example, 50% by mass or more, 80% by mass or less, or 50 to 80% by mass.

In each of the above embodiments, the adhesive component can also contain fillers such as silicone particles, softeners, accelerators, antioxidants, colorants, flame retardants, thixotropic agents, coupling agents, and the like. The filler is, for example, non-conductive particles. In addition to nano fillers such as silica and alumina, urethane, ester-based organic fillers, etc. can also be used. In addition to controlling the elastic modulus of the resin, these fillers also exert effects on the control of film formation and softening point.

In addition to the aromatic heterocyclic compound A, the adhesive component can also contain a compound having an aromatic heterocyclic ring. Examples of such compounds include 5-methyltetrazole, 5-amino-1H-tetrazole, 3-mercapto-1,2,4-triazole, benzotriazole, 2-aminopyrimidine, 5,6-Dimethylbenzimidazole, 2-amino-5-mercapto-1,3,4-thiadiazole, 2-mercaptopyrimidine, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole and so on.

In one embodiment, the adhesive composition may not contain conductive particles.

The adhesive composition may be in the form of a slurry or in the form of a film. From the viewpoint of handling properties, the adhesive composition may be formed into a thin film. When the adhesive composition is in the form of a slurry, the adhesive composition may contain a solvent such as an organic solvent. As an organic solvent, toluene, hexane, acetone, ethyl acetate, methyl ethyl ketone, ethanol, etc. are mentioned, for example. When the adhesive composition is in the form of a film, the adhesive composition may not substantially contain an organic solvent. Based on the total amount of the adhesive composition, the content of the organic solvent in the film-like adhesive composition is, for example, 1% by mass or less.

When the adhesive composition is formed into a film, in order to improve the film formability, the adhesive component may contain an insulating resin other than the above-mentioned thermosetting resin as a film forming component. Examples of insulating resins include polystyrene, polyethylene, polyvinyl butyral, polyvinyl alcohol, polyimide, polyamide, polyvinyl chloride, polyphenylene ether, urea resin, phenoxy Resin, polyimide resin, polyester urethane resin, etc. From the viewpoint of further improving connection reliability, the insulating resin may be a high-molecular-weight phenoxy resin with a weight average molecular weight of 10,000 or more determined by high performance liquid chromatography (HPLC). The adhesive component may contain those resins modified by radical polymerizable functional groups, and may contain a mixture of these resins and styrene resins or acrylic resins in order to adjust melt viscosity and the like. As another embodiment, in order to improve film forming properties, the adhesive component may contain rubber.

The adhesive composition described above exhibits excellent adhesive force when used as a material (circuit connection material) for the connection between circuit members, particularly for electrical connection between electrodes of the circuit member. That is, the above-mentioned adhesive composition is preferably used as a circuit connection material, and is particularly preferably used as an anisotropic conductive adhesive composition for connecting circuit members. Although the reason why the above-mentioned effect can be obtained is not clear, it is presumed as follows. First, in the conventional adhesive composition containing an aromatic heterocyclic compound, the aromatic heterocyclic compound is concentrated on the electrode surface side as the object to be adhered, and the radical polymerizability generated by curing of the adhesive composition The close contact between the polymer organic component such as the polymer of the compound and the object to be adhered is hindered by the above-mentioned aromatic heterocyclic compound. On the other hand, it is presumed that in the above-mentioned adhesive composition, the long-chain alkyl group and/or the long-chain alkylene group contained in the aromatic heterocyclic compound interact with the polymer organic component formed after curing. It functions to improve the adhesion with the adhered object, so the above-mentioned effects can be obtained. There is a tendency that the above-mentioned effect becomes remarkable when one or both of the electrodes to be bonded are formed of a metal material, and the metal material includes at least one selected from the group consisting of Cu and Ag.

＜Adhesive film＞ The adhesive film includes, for example, a layer formed of the adhesive composition of the above-mentioned embodiment. The adhesive film is preferably used as a circuit connection material, and is particularly preferably used as an anisotropic conductive adhesive film for connecting circuit members to each other. In addition, when the adhesive composition does not contain conductive particles, as described later, the adhesive film has a multilayer structure and may further include a layer containing conductive particles. Hereinafter, depending on the circumstances, the adhesive composition containing conductive particles in the adhesive composition of the above embodiment is referred to as the adhesive composition of the first embodiment, and the adhesive composition not containing conductive particles is referred to as the adhesive composition of the first embodiment. This is called the adhesive composition of the second embodiment.

Fig. 1 is a schematic cross-sectional view showing an adhesive film according to an embodiment. As shown in FIG. 1, in one embodiment, the adhesive film 1 is composed of a single layer formed of the adhesive component 2 and the conductive particles 3 dispersed in the adhesive component 2. In one embodiment, the adhesive component 2 and the conductive particles 3 may be the above-mentioned adhesive component and conductive particles. The thickness of the adhesive film 1 may be, for example, 10 μm or more, 50 μm or less, or 10-50 μm. As shown in FIG. 1, a substrate 100 such as a resin film (for example, a PET film) may be provided on the surface of the adhesive film 1. That is, in one embodiment, the adhesive film may be an adhesive film with a base material. The adhesive film 1 can be obtained, for example, by applying the slurry of the adhesive composition of the first embodiment to the substrate 100 using a knife coater, a roll coater, an applicator, etc. After application, heat is applied to reduce organic solvents.

In one embodiment, the adhesive film 1 can also have a multilayer structure of two or more layers. At this time, at least one of the outermost layers (layers provided on the outermost sides) of the layers constituting the multilayer structure is a layer formed of the adhesive composition of the above-mentioned embodiment. The multilayer structure may be a structure including a layer containing conductive particles and a layer not containing conductive particles, for example. Specifically, as shown in FIG. 2, the multilayer structure may be a layer containing conductive particles 3A (a layer formed of adhesive component 2A and conductive particles 3A dispersed in adhesive component 2A) 1A and not containing conductive The layer of sexual particles (the layer formed by the adhesive component 2B) 1B is a two-layer structure. In this case, as long as at least one layer is a layer formed of the adhesive composition of the above-mentioned embodiment (the adhesive composition of the first embodiment or the adhesive composition of the second embodiment), the two layers may be both. It is a layer formed of the adhesive composition of the above-mentioned embodiment. As shown in FIG. 3, the multilayer structure may be composed of a layer containing conductive particles 3A (a layer formed of the adhesive component 2A and the conductive particles 3A dispersed in the adhesive component 2A) 1A and a layer provided on both sides of the layer 1A. A three-layer structure composed of layers (layers formed of adhesive components 2B and 2C) 1B and 1C containing conductive particles. In this case, as long as at least one of the layers 1B and 1C not containing the conductive particles 3A as the outermost layer is a layer formed of the adhesive composition of the above-mentioned embodiment (the adhesive composition of the second embodiment), Both of these outermost layers may be layers formed of the adhesive composition of the above-mentioned embodiment (the adhesive composition of the second embodiment). In addition, the layer 1A containing the conductive particles 3A may be a layer formed of the adhesive composition of the above-mentioned embodiment (the adhesive composition of the first embodiment). The adhesive film of the multilayer structure may include a plurality of layers 1A containing conductive particles 3A, for example. Adhesive films of these multilayer structures can efficiently arrange conductive particles on the electrodes, and therefore are preferred for narrow-pitch connections. Considering the adhesiveness with the circuit member, the adhesive film may also have an adhesive layer showing high adhesiveness for each circuit member connected.

The multilayer structure may include, for example, a layer containing the aromatic heterocyclic compound A (a layer formed of the adhesive composition of the above embodiment) and a layer not containing the aromatic heterocyclic compound A. The layer containing the aromatic heterocyclic compound A and the layer not containing the aromatic heterocyclic compound A may be the outermost layer (layer exposed to the outside) of the adhesive film, respectively. Specifically, the multilayer structure may be a two-layer structure composed of a layer containing the aromatic heterocyclic compound A (a layer formed of the adhesive composition of the above embodiment) and a layer not containing the aromatic heterocyclic compound A. According to the adhesive film having such a multilayer structure, only one of the electrodes of the connected circuit member can be brought into contact with the layer selectively containing the aromatic heterocyclic compound A. For example, when only one of the electrodes of the circuit member is formed of a metal material containing at least one selected from the group consisting of Cu and Ag, the outermost layer on the side in contact with the electrode is made to contain aromatic The layer of heterocyclic compound A, so that the adhesive film shows high adhesion to each connected circuit member, and can bond the circuit members to each other more firmly. There is a tendency that when a layer that does not contain the aromatic heterocyclic compound A and does not contain a compound having an aromatic heterocyclic ring other than the aromatic heterocyclic compound A, the above-mentioned effects can be more remarkably obtained.

＜Connected structure＞ A method of manufacturing a connection structure according to an embodiment includes the steps of preparing a first circuit member having a first electrode and a second circuit member having a second electrode; and disposing the above-mentioned implementation between the first circuit member and the second circuit member A step of forming an adhesive composition; and a step of crimping the first circuit member and the second circuit member through the adhesive composition to electrically connect the first electrode and the second electrode to each other. In the step of disposing the adhesive composition, a slurry including the adhesive composition (adhesive slurry) may be disposed, or a film including the adhesive composition (adhesive film) may be disposed. Hereinafter, referring to the drawings, a method of manufacturing a bonded structure using the above-mentioned adhesive film 1 will be described.

4(a) and 4(b) are schematic cross-sectional views showing a method of manufacturing a connection structure according to an embodiment. First, as shown in FIG. 4(a), prepare a first circuit member 6 having a first substrate 4 and a first electrode 5 provided on the first substrate 4, and a first circuit member 6 having a second substrate 7 and provided on the second substrate 4. The second circuit member 9 of the second electrode 8 on the substrate 7.

Next, the first circuit member 6 and the second circuit member 9 are arranged such that the first electrode 5 and the second electrode 8 face each other, and the adhesive film 1 is arranged between the first circuit member 6 and the second circuit member 9.

Next, the adhesive film 1 is cured while pressing the entirety in the arrow A and arrow B directions. The pressure during pressurization may be, for example, 1 to 10 MPa per total connection area. The method of curing the adhesive film 1 may be a method based on heating, or a method of simultaneously using light irradiation in addition to heating. Heating can be performed at 100 to 170°C, for example. Pressurization and heating (light irradiation as required) can be performed, for example, for 1 to 160 seconds. Thereby, the first circuit member 6 and the second circuit member 9 are pressure-bonded via the cured product of the adhesive composition constituting the adhesive film 1.

In this embodiment, the adhesive film 1 is arranged between the first circuit member 6 and the second circuit member 9, but as another embodiment, an adhesive slurry (slurry adhesive composition) may be applied Replace the adhesive film on the first circuit member 6 or the second circuit member 9 or both.

As shown in FIG. 4(b), the connection structure 11 of one embodiment obtained as described above includes a first circuit member 6 having a first base material 4 and a first electrode 5 provided on the first base material 4 The second circuit member 9 has a second substrate 7 and a second electrode 8 provided on the second substrate 7; and the circuit connection member 10 is disposed between the first circuit member 6 and the second circuit member 9 and The first electrode 5 and the second electrode 8 are electrically connected to each other. The circuit connection member 10 is composed of a cured product of an adhesive composition, and is composed of a cured product 12 of the adhesive component 2 and conductive particles 3 dispersed in the cured product 12. In the connection structure 11, the first electrode 5 and the second electrode 8 are electrically connected to each other by allowing the conductive particles 3 to exist between the first electrode 5 and the second electrode 8.

Examples of the first base material 4 and the second base material 7 include a plastic substrate, a glass substrate, a composite substrate having a glass and/or plastic substrate and a conductive film and/or an insulating film provided on the substrate. The first substrate 4 and the second substrate 7 may be the same or different from each other.

The plastic substrate is, for example, an organic substrate formed of a thermoplastic resin. As a specific example, an organic substrate formed of an organic material can be cited. The organic material includes selected from the group consisting of polyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), and cycloolefin. At least one thermoplastic resin in the group consisting of polymer (COP) and polyethylene naphthalate (PEN).

The plastic substrate may also have a modified treatment film such as a hard coat layer and/or a protective film formed on the surface of the organic substrate and used to improve optical and mechanical properties. In order to facilitate the processing and transportation of the flexible substrate, a reinforcing material selected from glass materials, SUS, etc. can be bonded to the organic substrate.

From the viewpoint of ensuring the strength and flexibility of the film as a single substrate, the thickness of the plastic substrate may be 10 to 200 μm, or it may be 10 to 125 μm. The thickness of the plastic substrate can be 10 μm or more, 200 μm or less, or 125 μm or less.

If a conventional circuit connection material is used, the electrodes on the plastic substrate may be broken or cracked due to the heating and pressurization used to crimp the circuit members. In addition, with regard to the connection of electrodes that are difficult to form a sufficient electrical connection, in order to suppress damage to the electrodes, it is necessary to crimp the circuit members under conditions of lower temperature or lower stress. The adhesive film 1 of this embodiment can have more advantageous effects than conventional materials even in these points.

The glass substrate can be formed of soda glass, quartz glass, or the like. From the viewpoint of preventing damage caused by external stress, a chemical strengthening treatment may be applied to a substrate formed of these materials.

The composite substrate may have a glass substrate and/or a plastic substrate, and an insulating film and/or a conductive film arranged on the surface of the substrate and made of polyimide or decorative colored organic or inorganic materials. In the composite substrate, the electrode may be formed on the insulating film.

The combination of the first base material 4 and the second base material 7 is not particularly limited, but for example, it may be a combination of the first base material 4 being a plastic substrate and the second base material 7 being a plastic substrate, or the first base material 4 It is a plastic substrate and the second substrate 7 is a combination of a glass substrate or a composite substrate. When the first substrate 4 and the second substrate 7 are plastic substrates, the aforementioned adhesive film 1 is used for FOP (Film on Plastic substrate) connection.

Examples of electrode materials for forming the first electrode 5 and the second electrode 8 include metals such as Ag, Ni, Al, Au, Cu, Ti, Mo, and ITO, IZO, silver nanowire (wire), and nanocarbon. Transparent conductors such as tubes. There is a tendency that when one or both of the first electrode and the second electrode are formed of a metal material containing at least one selected from the group consisting of Cu and Ag, it is possible to significantly obtain an aromatic heterocyclic compound based A's anti-rust effect. From the viewpoint of reduction in connection resistance and easy availability, one or both of the first electrode and the second electrode may be formed of a metal material containing Cu (for example, copper, copper alloy, or copper oxide). In the case where the adhesive film has a multilayer structure, the electrode in contact with the outermost layer containing the aromatic heterocyclic compound A (the layer formed of the adhesive composition of the above-mentioned embodiment) may be composed of Cu and Ag An electrode formed of at least one metal material in the group. From the viewpoint of reduction in connection resistance and easy availability, the electrode in contact with the outermost layer containing the aromatic heterocyclic compound A (the layer formed of the adhesive composition of the above embodiment) may be made of a metal material containing Cu ( For example, electrodes formed of copper, copper alloys or copper oxides. The first electrode 5 and the second electrode 8 may be formed of the same material, or may be formed of different materials.

From the viewpoint of preventing disconnection, a surface layer such as an oxide or nitride film, an alloy film, or an organic film may be provided on the first electrode 5 and the second electrode 8. A first electrode 5 and a second electrode 8 may be respectively provided on the first circuit member 6 and the second circuit member 9, or a plurality of first electrodes 5 and second electrodes 8 may be respectively provided at predetermined intervals.

As a specific example of the first circuit member 6, a glass substrate in which a circuit is formed by a printed circuit board, ITO, or the like can be used. At this time, the base material (second base material 7) in the second circuit member 9 is, for example, a plastic substrate.

Electronic components such as active components such as semiconductor wafers, transistors, diodes, and thyristors, and passive components such as capacitors, resistors, and winding materials can also be used as the first circuit member 6. At this time, the substrate (second substrate 7) in the second circuit member 9 is, for example, a plastic substrate, a glass substrate, or a composite substrate. When the first circuit component 6 is an IC chip and the second substrate 7 is a plastic substrate, the above-mentioned adhesive film 1 is used for COP (Chip on Plastic substrate) connection.

As the first circuit member 6, for example, a circuit member having a protruding electrode (a semiconductor wafer having a protruding electrode, a glass substrate having a protruding electrode, etc.) can be used. The protruding electrode may be a bump formed by electroplating, or a wire bump formed by using a gold wire. The wire bump can be obtained by melting the tip of a gold wire with a torch or the like to form a gold ball, crimping the gold ball to the electrode pad of the base material having an electrode pad, and cutting the wire. [Example]

Hereinafter, examples will be given and the present disclosure will be described in more detail. However, the present disclosure is not limited to these embodiments.

<Example 1> As a radical polymerizable compound, urethane acrylate (product name: UA-5500T, manufactured by SHIN-NAKAMURA CHEMICAL CO, LTD.) 13 parts by mass, bis(acryloxyethyl) ) Isocyanurate (product name: M-215, manufactured by TOAGOSEI CO., LTD.) 10 parts by mass, dimethylol tricyclodecane diacrylate (product name: DCP-A, KYOEISHA CHEMICAL Co., LTD.) 5 parts by mass and 1 part by mass of 2-methacryloyloxyethyl acid phosphate (product name: P-2M, manufactured by KYOEISHA CHEMICAL Co., LTD.), as shown in the following formula (1) The aromatic heterocyclic compound A (1-[N,N-bis(2-ethylhexyl)aminomethyl]methylbenzotriazole, product name: TT-LX, manufactured by JOHOKU CHEMICAL CO.,LTD ) 1 part by mass, 5 parts by mass of benzoyl peroxide (product name: Niper BMT-K, manufactured by NOF CORPORATION) as a free radical generator, containing polyester urethane resin as an insulating resin (Product name: UR4800, manufactured by TOYOBO CO., LTD.) 52 parts by mass of methyl ethyl ketone solution is mixed and stirred to obtain a free radical polymerizable compound, aromatic heterocyclic compound A, free radical generator Solution of agent and insulating resin (hereinafter referred to as "solution A"). 【Chemical formula 1】

On the other hand, a metal layer (Ni layer: 200 nm, Au layer: 50 nm) is formed on the surface of the plastic particles (core) by electroplating of Ni and Au. Thus, conductive particles having an average particle diameter of 5 μm were obtained.

The conductive particles obtained in the above are dispersed in the solution A prepared in the above. The amount of conductive particles used was 5 parts by mass. Furthermore, silicone microparticles (product name: KMP-605, manufactured by Shin-Etsu Chemical Co., LTD.) having an average particle diameter of 2 μm were dispersed in a ratio of 13 parts by mass to obtain a coating liquid of the adhesive composition. In addition, all the above-mentioned compounding amounts are the amount with respect to the total of 100 parts by mass of the non-volatile components (except the conductive particles) in the adhesive composition. The coating liquid was coated on a polyethylene terephthalate (PET) film (thickness 50 μm) that was subjected to a mold release treatment on one side using a coating device. The coating film was dried by hot air drying at 70°C to form an anisotropic conductive adhesive film (thickness 18μm) formed of the adhesive composition on the PET film.

<Example 2> In Example 2, the aromatic heterocyclic compound A represented by the following formula (2) (1-[(2-ethylhexylamino)methyl]benzotriazole, the product Name: BT-260, manufactured by JOHOKU CHEMICAL CO., LTD) instead of the aromatic heterocyclic compound A represented by formula (1), except for this, an anisotropic conductive adhesive was produced in the same manner as in Example 1.剂膜。 Film. 【Chemical formula 2】

<Example 3> 12 parts by mass of bis(acryloxyethyl) isocyanurate (product name: M-215, manufactured by TOAGOSEI CO., LTD.) was used instead of 2-methacryloxyethyl acid Formula phosphate (product name: P-2M, manufactured by KYOEISHA CHEMICAL Co., LTD.), the aromatic heterocyclic compound A represented by formula (1) (1-[N,N-bis(2-ethylhexyl)) Except for aminomethyl]methylbenzotriazole, product name: TT-LX, manufactured by JOHOKU CHEMICAL CO., LTD, and conductive particles, the thickness was formed on the PET film in the same manner as in Example 1 A 13 μm adhesive film (adhesive layer A), thereby obtaining an adhesive film A with a PET film.

Except for changing the usage amount of the coating liquid of the adhesive composition, in the same manner as in Example 1, an anisotropic conductive adhesive film (adhesive layer B) with a thickness of 5 μm was formed on the PET film in the same manner as in Example 1. An adhesive film B with a PET film was obtained.

The adhesive film A with a PET film and the adhesive film B with a PET film were bonded together to obtain an anisotropic conductive adhesive film with a two-layer structure formed of the adhesive layer A and the adhesive layer B.

<Example 4> Except that conductive particles were not used, an adhesive film (adhesive layer C1) having a thickness of 1 μm was formed on the PET film in the same manner as in Example 1, thereby obtaining an adhesive film C1 with a PET film. In the same manner, no conductive particles were used, except that an adhesive film (adhesive layer C2) with a thickness of 12 μm was formed on the PET film in the same manner as in Example 1, thereby obtaining an adhesive film C2 with a PET film. .

11 parts by mass of bis(acryloxyethyl) isocyanurate (product name: M-215, manufactured by TOAGOSEI CO., LTD.) was used instead of the aromatic heterocyclic ring represented by formula (1) Compound A (1-[N,N-bis(2-ethylhexyl)aminomethyl]methylbenzotriazole, product name: TT-LX, manufactured by JOHOKU CHEMICAL CO., LTD), in addition, An anisotropic conductive adhesive film (adhesive layer D) having a thickness of 5 μm was formed on the PET film in the same manner as in Example 1, thereby obtaining an adhesive film D with a PET film.

The adhesive film C1 with a PET film and the adhesive film D with a PET film were bonded together, and a laminated body formed of the adhesive layer C1 and the adhesive layer D was obtained. Next, after removing the PET film on the side of the adhesive layer D (the PET film in the PET film-attached adhesive film D), the laminate and the PET film-attached adhesive film C2 are bonded to make the adhesive layer of the laminate D is in contact with the adhesive layer C2. Thereby, an anisotropic conductive adhesive film with a three-layer structure in which the adhesive layer C1, the adhesive layer D, and the adhesive layer C2 are sequentially laminated is obtained.

<Example 5> The aromatic heterocyclic compound A represented by formula (1) (1-[N,N-bis(2-ethylhexyl)aminomethyl]methylbenzotriazole, product name: TT-LX, JOHOKU The usage amount of CHEMICAL CO., LTD is set to 5 parts by mass, and the usage amount of polyester urethane resin (product name: UR4800, manufactured by TOYOBO CO., LTD.) is set to 48 parts by mass, except Otherwise, in the same manner as in Example 1, an anisotropic conductive adhesive film with a thickness of 18 μm was formed on the PET film.

<Comparative example 1 to comparative example 2> In Comparative Examples 1 to 2, instead of using the aromatic heterocyclic compound A, 5-methyltetrazole (product name: M5T, manufactured by Tokyo Kasei Kogyo Co., LTD.) or 3-mercaptotriazole ( Product name: 3MT, manufactured by Tokyo Kasei Kogyo Co., LTD.) instead of the aromatic heterocyclic compound A represented by formula (1), anisotropic conductivity was produced in the same manner as in Example 1, except that Adhesive film.

＜Comparative example 3＞ In Comparative Example 3, the aromatic heterocyclic compound A was not used, and an anisotropic conductive adhesive film was produced in the same manner as in Example 1 except that the aromatic heterocyclic compound A was not used.

＜Evaluation＞ [Evaluation of Connection Reliability] As a bonded body imitating a circuit member, a copper electrode film member having a PET film and a copper film formed on the PET film was prepared. On the copper film of the copper electrode film member, the adhesive film obtained above (the adhesive film of Example 1 to Example 5 and Comparative Example 1 to Comparative Example 3) was attached and heated to the thickness of the adhesive film When the reached temperature reached 70°C, the entire connection area was pressurized for 10 seconds at a pressure of 2 MPa per total connection area. At this time, the adhesive film of Example 3 was attached so that the surface of the adhesive layer B was in contact with the copper film, and the adhesive film of Example 4 was attached so that the surface of the adhesive layer C2 was in contact with the copper film. Thereby, a copper electrode film attached body provided with a cured body of the adhesive film (cured product of the adhesive composition from the adhesive film) was obtained. FIG. 5 is a schematic cross-sectional view showing the copper electrode film adhesive bodies of Example 1 to Example 2 and Example 5. FIG. FIG. 6 is a schematic cross-sectional view showing the copper electrode film attached body of Example 3. FIG. FIG. 7 is a schematic cross-sectional view showing the copper electrode film attached body of Example 4. FIG. FIG. 8 is a schematic cross-sectional view showing the copper electrode film adhesive bodies of Comparative Example 1 to Comparative Example 3. FIG. As shown in FIGS. 5 to 8, in the copper electrode film attached bodies 13A to 13D, a copper film 15 is formed on the PET film 14, and a surface 15a of the copper film 15 on the opposite side of the PET film 14 is provided Adhesive film cured body. The cured body 20A of the adhesive film shown in FIG. 5 is composed of a cured product of an adhesive composition containing an aromatic heterocyclic compound A and conductive particles (a cured product of an adhesive component containing an aromatic heterocyclic compound A and 22 The conductive particles 3 are formed) structure. The cured body 20B of the adhesive film shown in FIG. 6 is composed of a cured product of an adhesive composition containing an aromatic heterocyclic compound A and conductive particles (a cured product of an adhesive component containing an aromatic heterocyclic compound A and 22 The conductive particles 3 are formed) and the cured product of the adhesive composition not containing the aromatic heterocyclic compound A (formed of the cured product 32 of the adhesive component not containing the aromatic heterocyclic compound A). The cured body 20C of the adhesive film shown in FIG. 7 is composed of a cured product of an adhesive composition that contains conductive particles and does not contain an aromatic heterocyclic compound A (cured from an adhesive composition that does not contain an aromatic heterocyclic compound A The compound 32 and the conductive particles 3 are formed) and the cured product of the adhesive composition containing the aromatic heterocyclic compound A (the cured product 22 containing the adhesive component of the aromatic heterocyclic compound A). The cured body 20D of the adhesive film shown in FIG. 8 is composed of a cured product of an adhesive composition that contains conductive particles and does not contain an aromatic heterocyclic compound A (cured from an adhesive component that does not contain an aromatic heterocyclic compound A The object 32 and the conductive particles 3) are formed.

The obtained copper electrode film attached body was allowed to stand for 100 hours under an environment of 85° C. and 85% RH for the reliability test. With regard to the copper electrode film attached bodies 13 (13A to 13D) before and after the test, the appearance of the portion (attached portion) of the copper film 15 that is in contact with the cured product 20 on the surface 15a on the side opposite to the PET film 14 of the copper film 15 was observed with naked eyes. A person with almost no discoloration observed before and after the test was set as A, a person with a small discoloration observed but a small degree was set as B, and a person with severe discoloration (determined as corrosion) was set as C, and the reliability was evaluated. The results are shown in Table 1. Furthermore, if the evaluation result is A or B, it is judged that the connection reliability is excellent.

[Continuity Evaluation] As a bonded body imitating a circuit member, a copper electrode film member having a PET film and a copper film formed on the PET film was prepared. After attaching the adhesive film (the adhesive films of Example 1 to Example 5 and Comparative Example 1 to Comparative Example 3) obtained above on the copper electrode film member, the plastic circuit board was placed on the adhesive film On the upper side (the side opposite to the copper electrode film member), while heating until the reached temperature of the adhesive film becomes 170° C., the whole is pressurized at a pressure of 2 MPa per total connection area for 10 seconds. At this time, the adhesive film of Example 3 was attached so that the surface of the adhesive layer B was in contact with the copper film, and the adhesive film of Example 4 was attached so that the surface of the adhesive layer C2 was in contact with the copper film. In this way, the adhesive film mounting body a (connected structure body) was obtained. As a plastic circuit board, a Ni film (film thickness of 3μm) and Au film (film thickness of 0.01) formed on the surface with an electrode width of 150μm, a space between electrodes of 150μm, a distance between electrodes of 300μm, and a copper foil thickness of 18μm are used. μm).

The obtained adhesive film mounting body a was allowed to stand for 100 hours in an environment of 85° C. and 85% RH for reliability testing. The connection resistance of the adhesive film mounting body a after the test was measured. The results are shown in Table 1. Furthermore, a connection resistance of less than 1Ω was judged to have good continuity.

[Adhesion evaluation] _{A PET film (easy adhesion film) with SiO 2} film on the surface was used instead of the copper electrode film member as the adherend. In addition, it was installed with the adhesive film in [Conductivity Evaluation] The adhesive film mounting body b was obtained in the same manner as the manufacturing method of body a.

The obtained adhesive film mounting body b was allowed to stand for 100 hours in an environment of 85° C. and 85% RH for reliability testing. The adhesive film mounting body b after the test was cut into a width of 1 cm, and the FPC was peeled from the adhesive film mounting body b using a 90° peeling method to evaluate the adhesiveness. As a test device, Tensilon STA-1150 (product name, manufactured by A&D Company, Limited) was used. When the measured strength is 5 N/cm or more, it is judged that the adhesiveness is good.

【Table 1】 Aromatic heterocyclic compound Layer structure Evaluation type Allocation amount (parts by mass) reliability Continuity Continuity Example 1 TT-LX 1 Single layer A ＜1Ω 8N/cm Example 2 BT-260 1 Single layer A ＜1Ω 7N/cm Example 3 TT-LX 1 Double layer A ＜1Ω 9N/cm Example 4 TT-LX 1 Three layers A ＜1Ω 8N/cm Example 5 TT-LX 5 Single layer A ＜1Ω 9N/cm Comparative example 1 5-methyltetrazole 1 Single layer A ＜1Ω 4N/cm Comparative example 2 3-mercaptotriazole 1 Single layer A ＜1Ω 4N/cm Comparative example 3 none - Single layer C ＞5Ω 6N/cm

1: Adhesive film (adhesive composition) 2: Adhesive ingredients 3: conductive particles 4: The first substrate 5: The first electrode 6: The first circuit component 7: Second substrate 8: second electrode 9: The second circuit component 10: Circuit connection member (cured product of adhesive composition) 11: Connection structure

Fig. 1 is a schematic cross-sectional view showing an adhesive film (single-layer structure) according to an embodiment. Fig. 2 is a schematic cross-sectional view showing an adhesive film (two-layer structure) according to an embodiment. Fig. 3 is a schematic cross-sectional view showing an adhesive film (three-layer structure) according to an embodiment. In FIG. 4, FIG. 4(a) and FIG. 4(b) are schematic cross-sectional views which show the manufacturing method of the connection structure of an embodiment. Fig. 5 is a schematic cross-sectional view showing a copper electrode film attached body produced using the adhesive film (single-layer structure) of the embodiment. Fig. 6 is a schematic cross-sectional view showing a copper electrode film attached body produced using the adhesive film (double-layer structure) of the embodiment. FIG. 7 is a schematic cross-sectional view showing a copper electrode film attached body manufactured using the adhesive film (three-layer structure) of the embodiment. Fig. 8 is a schematic cross-sectional view showing a copper electrode film attached body produced using the adhesive film of the comparative example.

1: Adhesive film (adhesive composition)

2: Adhesive ingredients

3: conductive particles

100: Substrate

Claims (12)

An adhesive composition comprising a compound comprising an aromatic heterocyclic ring and a compound which is bonded to the aforementioned aromatic heterocyclic ring and is selected from the group consisting of an alkyl chain having 3 or more carbon atoms and an alkylene chain having 3 or more carbon atoms At least one side chain group in the group. The adhesive composition according to claim 1, wherein The aforementioned aromatic heterocyclic ring contains a nitrogen atom as a hetero atom. The adhesive composition according to claim 1 or claim 2, wherein: The aforementioned side chain group includes two or more alkyl chains with 3 or more carbon atoms. The adhesive composition according to any one of claims 1 to 3, which further contains conductive particles. The adhesive composition according to any one of claims 1 to 4, wherein: When the total of the components other than the conductive particles in the non-volatile components contained in the adhesive composition is 100 parts by mass, the content of the compound is 0.01 to 10 parts by mass. The adhesive composition according to any one of claims 1 to 5, which is used to connect circuit members to each other. An adhesive film provided with a layer formed of the adhesive composition according to any one of claims 1 to 6. The adhesive film according to claim 7, which has a multilayer structure of two or more layers, At least one of the outermost layers of the layers constituting the aforementioned multilayer structure is a layer formed of the aforementioned adhesive composition. The adhesive film according to claim 8, wherein At least one of the layers constituting the aforementioned multilayer structure is a layer containing conductive particles. A connection structure, which has: The first circuit member has a first electrode; the second circuit member has a second electrode; and a circuit connection member is arranged between the first circuit member and the second circuit member and connects the first electrode and The aforementioned second electrodes are electrically connected to each other, The aforementioned circuit connection member includes a cured product of the adhesive composition described in any one of claim 1 to claim 6. The connection structure described in claim 10, wherein: One or both of the first electrode and the second electrode are formed of a metal material, and the metal material includes at least one selected from the group consisting of Cu and Ag. A manufacturing method of a connecting structure, the manufacturing method comprising: The step of preparing a first circuit member with a first electrode and a second circuit member with a second electrode; The step of disposing the adhesive composition according to any one of claim 1 to claim 6 between the aforementioned first circuit component and the aforementioned second circuit component; and The step of crimping the first circuit member and the second circuit member via the adhesive composition to electrically connect the first electrode and the second electrode to each other.

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