Resin composition, anisotropic conductive film, anisotropic conductive film structure, method for manufacturing a connecting structure, and method for dismantling

Abstract

The present invention aims to provide a resin composition that can achieve both connection reliability and ease of disassembly, and an anisotropic conductive film made from the resin composition. It also aims to provide a method for manufacturing a connection structure using the anisotropic conductive film and a method for disassembling the connection structure. [Solution] The resin composition of the present invention is characterized by comprising (a) conductive particles and (b) a crosslinked resin having dynamic covalent bonds.

Description

[Technical Field]

[0001] The present invention relates to a resin composition, an anisotropic conductive film, an anisotropic conductive film structure, a method for manufacturing a connecting structure, and a method for disassembling it. [Background technology]

[0002] Anisotropic conductive film is a film in which conductive particles are dispersed in an insulating adhesive film, and is a connecting member used to easily connect liquid crystal displays to semiconductor chips or TCPs (Tape Carrier Packages), or to FPCs (Flexible Printed Circuits) to TCPs, or to FPCs to printed circuit boards. For example, it is widely used for connecting liquid crystal displays and control ICs (Integrated Circuits) in notebook computers and mobile phones, and recently it has also been used in flip-chip mounting, where semiconductor chips are directly mounted on printed circuit boards or flexible circuit boards (Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-32799 [Overview of the project] [Problems that the invention aims to solve]

[0004] As described in Patent Document 1, anisotropic conductive films include thermoplastic types using thermoplastic resins as adhesive components and thermosetting types using thermosetting resins as adhesive components. While thermosetting types offer high reliability due to the thermosetting resin, in principle, it is difficult to break molecular bonds, requiring a great deal of energy to break the bonds and potentially destroying structural components. Therefore, in many cases, dismantling structural components is impossible. Consequently, rework is virtually impossible, and recycling of circuit boards and circuit components has also been virtually impossible.

[0005] An object of the present invention is to provide a resin composition capable of achieving both connection reliability and easy disassembly, an anisotropic conductive film made of the resin composition, etc. Another object is to provide a method for manufacturing a connection structure using the anisotropic conductive film and a method for disassembling the connection structure.

Means for Solving the Problems

[0006] As a result of intensive studies to solve the above problems, the present inventor has found that a resin composition containing conductive particles and a crosslinked resin having dynamic covalent bonds, and an anisotropic conductive film made thereof can solve the above problems, and thus the present invention has been completed.

[0007] That is, the present invention is as follows. [1] (a) Conductive particles, and (b) A crosslinked resin having dynamic covalent bonds, A resin composition containing the same. [2] The resin composition according to [1], wherein the crosslinked resin (b) having dynamic covalent bonds further has a skeleton derived from an epoxy group. [3] The resin composition according to [1] or [2], wherein the dynamic covalent bond has any one of a vinylogous urethane bond, a vinylogous urea bond, a vinylogous amide bond, an imine bond, or a diketoenamine bond. [4] The storage elastic modulus E' at 23°C in dynamic viscoelasticity measurement is 5.0×10 5 Pa to 1.0×10 10 Pa, the resin composition according to any one of [1] to [3]. [5] The resin composition according to any one of [1] to [4], wherein the tanδ peak temperature in dynamic viscoelasticity measurement is -20°C to 130°C. [6] The resin composition according to any one of [1] to [5], wherein the bond exchange temperature Tv is 50°C to 150°C. [7] A resin composition according to any one of [1] to [6], wherein the gel fraction is 40% to 100%. [8] An anisotropic conductive film comprising a resin composition as described in any of [1] to [7]. [9] An anisotropic conductive film as described in [8], having an average thickness of 5 μm to 100 μm, an average width of 0.2 mm to 50 mm, and a length of 5 m to 500 m.

[10] An anisotropic conductive film as described in [8] or [9], wherein the elongation in a tensile test at 23°C is 10% to 1000%.

[11] An anisotropic conductive film as described in any of [8] to

[10] , wherein the maximum stress in a tensile test at 23°C is 1 MPa to 100 MPa.

[12] An anisotropic conductive film as described in any of [8] to

[11] , having a shear adhesion strength of 1 MPa to 60 MPa.

[13] An anisotropic conductive film structure comprising an anisotropic conductive film as described in any of [8] to

[12] and a release film in contact with one side of the anisotropic conductive film.

[14] The anisotropic conductive film structure according to

[13] , further comprising a cover film in contact with the side of the anisotropic conductive film opposite to the one side.

[15] A method for manufacturing a connection structure, comprising the steps of sandwiching an anisotropic conductive film described in any of [8] to

[12] between a circuit board and a circuit member having mutually opposing terminals, and applying heat and / or pressure to create electrical conductivity between the terminals of the circuit board and the terminals of the circuit member.

[16] A method for disassembling a connection structure having an anisotropic conductive film as described in any of [8] to

[12] between a circuit board and a circuit member having mutually opposing terminals, (A) A step of heating or heating and pressurizing the anisotropic conductive film, (B) A step after step (A) in which an anisotropic conductive film is peeled off from the circuit board or circuit member, Demolition methods, including those mentioned above.

[17] The demolition method according to

[16] , wherein the heating temperature of the heating or heating and pressurizing step is (b) the bond exchange temperature of the crosslinked resin having dynamic covalent bonds, Tv + 5°C or higher and the bond exchange temperature of Tv + 30°C or lower.

[18] (C) The dismantling method according to

[16] or

[17] , further comprising the step of cleaning the surface of a circuit board or circuit member after step (B). [Effects of the Invention]

[0008] The present invention provides a resin composition that achieves both connection reliability and ease of disassembly, and an anisotropic conductive film made from the resin composition. Furthermore, it provides a method for manufacturing a connection structure using the anisotropic conductive film and a method for disassembling the connection structure. [Modes for carrying out the invention]

[0009] The embodiments for carrying out the present invention will be described in detail below. However, the present invention is not limited to the following description and can be implemented in various modifications within the scope of its gist.

[0010] [Resin composition] The resin composition of this embodiment comprises (a) conductive particles and (b) a crosslinked resin having dynamic covalent bonds. The resin composition of this embodiment may consist only of (a) conductive particles and (b) a crosslinked resin having dynamic covalent bonds, or it may further contain other components.

[0011] <(a) Conductive particles> The conductive particles in (a) above are not limited to those having conductive parts within the particle, and for example, metal particles or particles in which a thin metal film is coated on a polymer core material can be used.

[0012] As metal particles, particles having a uniform composition consisting of metal or alloy are used. Examples of metal particles include gold, silver, copper, nickel, aluminum, zinc, tin, lead, solder, indium, palladium, and particles in which two or more of these metals are combined in layers or in a gradient.

[0013] Examples of particles coated with a thin metal film over a polymer core include particles in which a thin metal film is coated over a polymer core made of at least one polymer selected from the group consisting of epoxy resin, styrene resin, silicone resin, acrylic resin, polyolefin resin, melamine resin, benzoguanamine resin, urethane resin, phenolic resin, polyester resin, divinylbenzene crosslinked material, nitrile rubber (NBR), and styrene-butadiene rubber (SBR), in combination with one or more metals selected from the group consisting of gold, silver, copper, nickel, aluminum, zinc, tin, lead, solder, indium, and palladium.

[0014] The thickness of the metal thin film is preferably in the range of 0.005 μm to 1 μm from the viewpoint of connection stability and particle aggregation. For connection stability, it is preferable that the metal thin film is uniformly coated. A method for coating the polymer core material with a metal thin film is, for example, plating. In particular, particles in which a polymer core material is coated with a thin metal film are preferred, particles in which the polymer core material is coated with gold are even more preferred, and particles in which the polymer core material is coated with nickel and then further coated with gold are even more preferred. The polymer core material is preferably one or more selected from benzoguanamine resin, divinylbenzene crosslinked material, and acrylic resin.

[0015] The average particle size of the conductive particles is preferably in the range of 0.5 μm to 6.0 μm from the viewpoint of conductivity in the thickness direction, insulation in the plane direction (hereinafter often referred to as anisotropic conductivity), and aggregation of conductive particles. More preferably, the average particle size of the conductive particles is 1.0 μm to 5.5 μm, even more preferably 1.5 μm to 5.0 μm, and still more preferably 2.0 μm to 4.5 μm. The standard deviation of the particle size of the conductive particles is preferably as small as possible, preferably 50% or less of the average particle size. Even more preferably 20% or less, even more preferably 10% or less, and even more preferably 5% or less. The average particle size of the conductive particles in this embodiment was measured using a Coulter counter.

[0016] Conductive particles can also be coated with an insulating material. Coating conductive particles with an insulating material is preferable because it tends to prevent short circuits between connected electrodes.

[0017] <(b) Crosslinked resins with dynamic covalent bonds> In this embodiment, a crosslinked resin having dynamic covalent bonds (hereinafter also simply referred to as a crosslinked resin) is a resin having a crosslinked structure and possessing "dynamic covalent bonds" that can reversibly "dissociate and bond" in response to external stimuli such as heat (temperature), light, or catalysts. Examples of bond types that form dynamic covalent bonds include vinylogous urethane bonds (hereinafter sometimes abbreviated as VU bonds), vinylogous urea bonds, vinylogous amide bonds, imine bonds, diketoenamine bonds, ester bonds, carbonate bonds, cyclic acetal bonds, quaternary ammonium salt bonds, oxazoline bonds, spiro-orthoester bonds, borate ester bonds, disulfide bonds, Diels-Alder bonds, and the like. The above dynamic covalent bond is preferably a vinylogous urethane bond, a vinylogous urea bond, a vinylogous amide bond, an imine bond, or a diketoenamine bond, from the viewpoint of better dispersibility of conductive particles in the resin composition and better connection reliability and ease of disassembly of the anisotropic conductive film, and is more preferably a vinylogous urethane bond, a vinylogous urea bond, a vinylogous amide bond, an imine bond, or a diketoenamine bond.

[0018] In the crosslinked resin, the dynamic covalent bonds described above may be present in the main chain or in the side chains. That is, the reactive groups or bonds that form the dynamic covalent bonds may be located in the main chain of the polymer or as substituents, etc., in the side chains of the polymer. Preferably, the crosslinked resin has, as the dynamic covalent bonds, one selected from the group consisting of vinylogous urethane bonds, imine bonds, diketoenamine bonds, ester bonds, disulfide bonds, and Diels-Alder bonds. More preferably, it is one selected from the group consisting of VU bonds, imine bonds, diketoenamine bonds, and disulfide bonds. Furthermore, the crosslinked resin may simultaneously contain two or more types selected from the above group as dynamic covalent bonds.

[0019] (Vinyl gas urethane bonding) The vinylogas urethane bond described above is not particularly limited, but may be a structure represented by the following formula (1). [ka] In equation (1), the zigzag lines represent bonds and indicate bonding with any chemical structure. The vinylogas urethane bond described above may be formed, for example, as shown below. (i) A bond formed by dehydration condensation between an acetoacetate ester compound having one or more (preferably two or more) acetoacetate ester groups in the molecule and an amine compound having two or more primary or secondary amino groups in the molecule. (ii) A bond formed by the addition of an amine compound having two or more primary amino groups in its molecule to a propargyl acid ester compound.

[0020] The acetoacetate ester compound used as the raw material for (i) is not particularly limited, but examples include the following compounds. The bisacetoacetate compounds having two acetoacetate groups in the molecule are not particularly limited, but examples include alkanediol bisacetoacetates such as ethylene glycol-1,2-bisacetoacetate, propanediol-1,3-bisacetoacetate, propanediol-1,2-bisacetoacetate, butanediol-1,4-bisacetoacetate, hexanediol-1,6-bisacetoacetate, and decanediol-1,10-bisacetoacetate; oxyalkylenediol bisacetoacetates such as diethylene glycol bisacetoacetate, triethylene glycol bisacetoacetate, polyethylene glycol bisacetoacetate, and polypropylene glycol bisacetoacetate; and 1,4-cyclohexanedimethanol bisacetoacetate. From the viewpoint of the strength, film strength, and self-healing properties of the resulting crosslinked resin, ethylene glycol-1,2-bisacetoacetate, polyethylene glycol bisacetoacetate, polypropylene glycol bisacetoacetate, and 1,4-cyclohexanedimethanol bisacetoacetate are particularly preferred among these. The above bisacetoacetate compounds may be used individually or in combination of two or more.

[0021] Acetoacetate ester compounds having three or more acetoacetate groups are not particularly limited, but include esters of polyols such as triols with three or more acetylacetates. Specifically, examples include polyacetoacetates such as trisacetoacetate and tetrakisacetoacetate. Examples of trisacetoacetate are not particularly limited, but include trimethylolpropane trisacetoacetate, trisacetoacetate-1,2,3-propanetriol, trisacetoacetate-1,2,4-butanetriol, and trisacetoacetate-1,2,6-hexanetriol. Other polyacetoacetates are not particularly limited, but include pentaerythritol tetrakisacetoacetate, as well as those that can be obtained by the method described in Japanese Patent Publication No. 2017-533088. From the viewpoint of the strength of the resulting crosslinked resin and the adhesive strength as an adhesive, trimethylolpropane trisacetoacetate and trisacetoacetate-1,2,3-propanetriol are particularly preferred among these. The acetoacetate ester compounds having three or more acetoacetate groups in their molecule may be used individually or in combination of two or more.

[0022] When the acetoacetate compound contains a monoacetoacetate compound, the monomer units derived from the monoacetoacetate compound are preferably greater than 0 parts by mass and 25 parts by mass or less, more preferably greater than 0 parts by mass and 20 parts by mass or less, even more preferably greater than 0 parts by mass and 15 parts by mass or less, and most preferably greater than 0 parts by mass and 10 parts by mass or less, based on 100 parts by mass of the total amount of crosslinked resin. When the content of monomer units derived from the monoacetoacetate compound is within the above range, the three-dimensional crosslinks formed by the condensation reaction between the acetoacetate group of monomer units derived from a polyfunctional acetoacetate compound having two or more acetoacetate groups and the primary amino group of the amine compound are appropriately controlled, and high adhesive strength, good viscosity, and film strength tend to be obtained. When the acetoacetate compound contains a bisacetoacetate compound, the content is preferably 20 to 100 parts by mass, more preferably 30 to 100 parts by mass, more preferably 40 to 100 parts by mass, even more preferably 80 to 100 parts by mass, even more preferably 85 to 100 parts by mass, and even more preferably 90 to 100 parts by mass. When the content of monomer units derived from the bisacetoacetate compound is within the above range, the three-dimensional crosslinks formed by the condensation reaction between the acetoacetate group of the bisacetoacetate compound and the primary or secondary amino group of the amine compound are appropriately controlled, and high mechanical properties and strong adhesive strength tend to be obtained. When the acetoacetate ester compound includes an acetoacetate ester compound having three or more acetoacetate groups in its molecule, the monomer units derived from the acetoacetate ester compound having three or more acetoacetate groups in its molecule are preferably greater than 0 parts by mass and 60 parts by mass or less, more preferably greater than 0 parts by mass and 50 parts by mass or less, more preferably greater than 0 parts by mass and 40 parts by mass or less, more preferably greater than 0 parts by mass and 30 parts by mass or less, and more preferably greater than 0 parts by mass and 20 parts by mass or less, based on 100 parts by mass of the total amount of crosslinked resin. When the content of monomer units derived from the acetoacetate ester compound having three or more acetoacetate groups in its molecule is within the above range, the three-dimensional crosslinking formed by the condensation reaction between the acetoacetate group of the acetoacetate ester compound having three or more acetoacetate groups in its molecule and the primary or secondary amino group of the amine compound is appropriately adjusted, and high mechanical properties and good adhesive strength tend to be obtained.

[0023] The amine compound having two or more primary or secondary amino groups that serves as the raw material for (i) is not particularly limited, but it is preferably an amine compound having two or more primary amino groups. The amine compound having two or more primary amino groups also serves as the raw material for (ii). The amine compound may be a diamine, triamine, or polyamine, and may be an aromatic amine, an aliphatic amine, a compound having both an aliphatic amino group and an aromatic amino group, a heterocyclic amine, or an alicyclic amine. The amine compound may be used alone or in combination of two or more types.

[0024] More specifically, the following compounds are examples of the amine compounds in question. Examples of aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 3,5-diaminotoluene, 1,4-diamino-2-methoxybenzene, 2,5-diamino-p-xylene, 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid, 1,4-diamino-2,5-dichlorobenzene, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-2,2'-dimethylbibenzyl, 4,4'-diaminodiphenylmethane, 3, 3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 2,2'-diaminostilbene, 4,4'-diaminostilbene, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminobenzophenone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene Benzene, 1,4-bis(4-aminophenoxy)benzene, 3,5-bis(4-aminophenoxy)benzoic acid, 4,4'-bis(4-aminophenoxy)bibenzyl, 2,2-bis[(4-aminophenoxy)methyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, 1,1-bis(4-aminophenyl)cyclohex Sun, α,α'-bis(4-aminophenyl)-1,4-diisopropylbenzene, 9,9-bis(4-aminophenyl)fluorene, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-diaminodiphenylamine, 2,4-diaminodiphenylamine, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoanthraquinone, 1,3-diaminopyrene, 1,6-diaminopyrene, 1,8-diaminopyrene, 2,7-diaminofluorene, 1,3-Bis(4-aminophenyl)tetramethyldisiloxane, benzidine, 2,2'-dimethylbenzidine, 1,2-bis(4-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,5-bis(4-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1,7-bis(4-aminophenyl)heptane, 1,8-bis(4-aminophenyl)octane, 1,9-bis(4-aminophenyl)nonane, 1,1 0-Bis(4-aminophenyl)decane, 1,3-Bis(4-aminophenoxy)propane, 1,4-Bis(4-aminophenoxy)butane, 1,5-Bis(4-aminophenoxy)pentane, 1,6-Bis(4-aminophenoxy)hexane, 1,7-Bis(4-aminophenoxy)heptane, 1,8-Bis(4-aminophenoxy)octane, 1,9-Bis(4-aminophenoxy)nonane, 1,10-Bis(4-aminophenoxy)decane, Di(4-aminophenyl)propane-1,3-GioA To, di(4-aminophenyl)butane-1,4-dioate, di(4-aminophenyl)pentane-1,5-dioate, di(4-aminophenyl)hexane-1,6-dioate, di(4-aminophenyl)heptane-1,7-dioate, di(4-aminophenyl)octane-1,8-dioate, di(4-aminophenyl)nonane-1,9-dioate, di(4-aminophenyl)decane-1,10-dioate, 1,3-bis[4-(4-aminophenoxy)phenoxy]propane, 1,4- Examples include bis[4-(4-aminophenoxy)phenoxy]butane, 1,5-bis[4-(4-aminophenoxy)phenoxy]pentane, 1,6-bis[4-(4-aminophenoxy)phenoxy]hexane, 1,7-bis[4-(4-aminophenoxy)phenoxy]heptane, 1,8-bis[4-(4-aminophenoxy)phenoxy]octane, 1,9-bis[4-(4-aminophenoxy)phenoxy]nonane, and 1,10-bis[4-(4-aminophenoxy)phenoxy]decane.

[0025] Examples of aromatic-aliphatic diamines include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, 4-amino-N-methylbenzylamine, 3-aminophenethylamine, 4-aminophenethylamine, 3-amino-N-methylphenethylamine, 4-amino-N-methylphenethylamine, 3-(3-aminopropyl)aniline, 4-(3-aminopropyl)aniline, 3-(3-methylaminopropyl)aniline, 4-(3-methylaminopropyl)aniline, 3-(4- Examples include minobutyl)aniline, 4-(4-aminobutyl)aniline, 3-(4-methylaminobutyl)aniline, 4-(4-methylaminobutyl)aniline, 3-(5-aminopentyl)aniline, 4-(5-aminopentyl)aniline, 3-(5-methylaminopentyl)aniline, 4-(5-methylaminopentyl)aniline, 2-(6-aminonaphthyl)methylamine, 3-(6-aminonaphthyl)methylamine, 2-(6-aminonaphthyl)ethylamine, and 3-(6-aminonaphthyl)ethylamine.

[0026] Examples of heterocyclic diamines include 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-diaminodibenzofuran, 3,6-diaminocarbazole, 2,4-diamino-6-isopropyl-1,3,5-triazine, and 2,5-bis(4-aminophenyl)-1,3,4-oxadiazole.

[0027] Examples of aliphatic diamines include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylheptane, 1,12-diaminododecane, 1,18-diaminooctadecane, and 1,2-bis(3-aminopropoxy)ethane.

[0028] Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, and isophorone diamines. From the viewpoint of improving reactivity, among these aliphatic diamines, those in which the amino group is located at the end of the molecular chain are preferred.

[0029] From the viewpoint of high mechanical properties and good fluidity, 1,6-diaminohexane is particularly preferred among these. The above diamine compounds may be used individually or in combination of two or more. Specific examples of aromatic triamines include 1,3,5-triaminobenzene, tris(3-aminophenyl)amine, tris(4-aminophenyl)amine, tris(3-aminophenyl)benzene, tris(4-aminophenyl)benzene, 1,3,5-tris(3-aminophenoxy)benzene, 1,3,5-tris(4-aminophenoxy)benzene [TAPOB], 1,3,5-tris(aminophenyl)benzene [TAPB], or 1,3,5-tris(4-aminophenoxy)triazine.

[0030] Furthermore, it is also possible to use aromatic triamines having a predetermined asymmetric structure represented by the following general formula (2). [ka] (In formula (2), -Z- is -O-, -CO-, -S-, -SO2-, -CH2-, -C(CH3)2-, -C(CF3)2-, or a single bond. Ra and Rb are independently a hydrogen atom, a halogen atom, a hydroxyl group, or a hydrocarbon group. m is an integer from 0 to 3, and n is an integer from 0 to 4.)

[0031] Specific examples of aromatic triamines having a predetermined asymmetric structure represented by the general formula (2) above include 2,3',4-triaminobiphenyl, 2,4,4'-triaminobiphenyl, 3,3',4-triaminobiphenyl, 3,3',5-triaminobiphenyl, 3,4,4'-triaminobiphenyl, 3,4',5-triaminobiphenyl, 2,3',4-triaminodiphenyl ether, 2,4,4'-triaminodiphenyl ether, 3,3',4-triaminodiphenyl ether, 3,3',5-triaminodiphenyl ether, and 3,4,4'-triaminodiphenyl ether. Triaminodiphenyl ether, 3,4',5-triaminodiphenyl ether, 2,3',4-triaminobenzophenone, 2,4,4'-triaminobenzophenone, 3,3',4-triaminobenzophenone, 3,3',5-triaminobenzophenone, 3,4,4'-triaminobenzophenone, 3,4',5-triaminobenzophenone, 2,3',4-triaminodiphenyl sulfide, 2,4,4'-triaminodiphenyl sulfide, 3,3',4-triaminodiphenyl sulfide, 3,3',5-triaminodiphenyl sulfide 3,4,4'-triaminodiphenyl sulfide, 3,4',5-triaminodiphenyl sulfide, 2,3',4-triaminodiphenyl sulfone, 2,4,4'-triaminodiphenyl sulfone, 3,3',4-triaminodiphenyl sulfone, 3,3',5-triaminodiphenyl sulfone, 3,4,4'-triaminodiphenyl sulfone, 3,4',5-triaminodiphenyl sulfone, 2,3',4-triaminodiphenylmethane, 2,4,4'-triaminodiphenylmethane, 3,3',4-triaminodiphenyl Tan, 3,3',5-triaminodiphenylmethane, 3,4,4'-triaminodiphenylmethane, 3,4',5-triaminodiphenylmethane, 2-(2,4-diaminophenyl)-2-(3-aminophenyl)propane, 2-(2,4-diaminophenyl)-2-(4-aminophenyl)propane, 2-(3,4-diaminophenyl)-2-(3-aminophenyl)propane, 2-(3,5-diaminophenyl)-2-(3-aminophenyl)propane, 2-(3,Examples include 5-diaminophenyl)-2-(4-aminophenyl)propane, 2-(2,4-diaminophenyl)-2-(3-aminophenyl)hexafluoropropane, 2-(2,4-diaminophenyl)-2-(4-aminophenyl)hexafluoropropane, 2-(3,4-diaminophenyl)-2-(3-aminophenyl)hexafluoropropane, 2-(3,5-diaminophenyl)-2-(3-aminophenyl)hexafluoropropane, 2-(3,4-diaminophenyl)-2-(4-aminophenyl)hexafluoropropane, and 2-(3,5-diaminophenyl)-2-(4-aminophenyl)hexafluoropropane. Among the aromatic triamines mentioned above, those exhibiting a symmetrical molecular structure are preferred.

[0032] Aliphatic triamines are not particularly limited, but examples include 1,2,3-triaminopropane, 1,3,5-triaminocyclohexane, and tris(2-aminoethyl)amine.

[0033] Specific examples of amine compounds having both aliphatic and aromatic amino groups include 5-(2-aminoethyl)benzene-1,3-diamine and 2-((4-aminophenoxy)methyl)propane-1,3-diamine.

[0034] As amine compounds having three or more primary amino groups in the molecule, commercially available products can also be used. Examples include JEFFAMINE T-403, JEFFAMINE T-3000, and JEFFAMINE T-5000 from Huntsman, as well as Polyment NK-350 from Nippon Shokubai Co., Ltd. and Hexatran 110 from Ascend. Furthermore, amine compounds having three or more primary amino groups in their molecule include amino group-modified polysiloxanes. For example, X-22-3939A manufactured by Shin-Etsu Silicone Co., Ltd. is one such example. From the standpoint of high mechanical properties and good fluidity, Hexatran 110 manufactured by Ascend is particularly preferred among these. The amine compounds having three or more primary amino groups in the molecule may be used individually or in combination of two or more types.

[0035] The amount of primary amino groups in monomer units derived from amine compounds having two or more primary amino groups in the molecule is preferably 0.9 to 1.30 equivalents, and more preferably 1.0 to 1.10 equivalents, relative to the amount of acetoacetate groups in monomer units derived from acetoacetate compounds. When the amount of primary amino groups is within the above range, the density of the three-dimensional crosslinked structure formed by the condensation reaction between the acetoacetate groups of the acetoacetate compound and the primary amino groups of the amine compound is appropriately adjusted, and high mechanical properties and good fluidity tend to be obtained.

[0036] When the acetoacetate ester compound contains a bisacetoacetate ester compound, the monomer units derived from the amine compound are preferably 23 to 63 mol%, more preferably 33 to 53 mol%, and even more preferably 38 to 48 mol%, based on the total monomer unit content of the crosslinked resin being 100 mol%. When the content of monomer units derived from the amine compound is within the above range, the density of the three-dimensional crosslinked structure formed by the condensation reaction between the acetoacetate ester group of the acetoacetate ester compound and the primary amino group of the amine compound is appropriately adjusted, and high mechanical properties and good fluidity tend to be obtained. When the acetoacetate ester compound contains three or more acetoacetate groups in its molecule, the monomer units derived from the amine compound are preferably 43 to 83 mol%, more preferably 53 to 73 mol%, and even more preferably 58 to 68 mol%, based on the total monomer unit content of the crosslinked resin being 100 mol%. When the content of monomer units derived from the amine compound is within the above range, the density of the three-dimensional crosslinked structure formed by the condensation reaction between the acetoacetate group of the acetoacetate ester compound and the primary amino group of the amine compound is appropriately adjusted, and high mechanical properties and good fluidity tend to be obtained. The above-mentioned crosslinked resin preferably contains monomer units derived from amine compounds having two or more primary amino groups in the molecule, and may also contain monomer units derived from monoamines to the extent that it does not contradict the purpose of the invention. Examples of monoamines include n-butylamine and benzylamine.

[0037] The propargyl ester compound used as the raw material for (ii) is not particularly limited. It may be a propargyl ester compound having one propargyl ester group in the molecule, a propargyl ester compound having two propargyl ester groups in the molecule, or a propargyl ester compound having three or more propargyl ester groups in the molecule.

[0038] The propargyl ester compound having one propargyl ester group in its molecule is not particularly limited, but examples include esters of propargyl acid with alcohols such as monoalcohols, diols, and triols. Among these, from the viewpoint of adhesive strength, esters of one propargyl acid with polyhydric alcohols such as ethylene glycol monopropargyl ester and polypropylene glycol monopropargyl ester are particularly preferred.

[0039] Examples of propargyl ester compounds (bispropargyl ester compounds) that have one propargyl ester group in their molecule include esters of two propargyl acids with polyols such as diols and triols. Examples of bispropargyl ester compounds are not particularly limited, but include ethylene glycol-1,2-bispropargyl ester, propanediol-1,3-bispropargyl ester, propanediol-1,2-bispropargyl ester, butanediol-1,4-bispropargyl ester, hexanediol-1,6-bispropargyl ester, decanediol-1,10-bispropargyl ester, and other alkanediol bispropargyl esters; diethylene glycol bispropargyl ester, triethylene glycol bispropargyl ester, polyethylene glycol bispropargyl ester, polypropylene glycol bispropargyl ester, and other oxyalkylenediol bispropargyl esters; and 1,4-cyclohexanedimethanol bispropargyl ester. From the viewpoint of adhesive strength, among these, ethylene glycol-1,2-bispropagilate, polyethylene glycol bispropagilate, polypropylene glycol bispropagilate, and 1,4-cyclohexanedimethanol bispropagilate are particularly preferred. The above-mentioned bispropargyl ester compounds may be used individually or in combination of two or more.

[0040] Examples of propargyl ester compounds having three or more propargyl ester groups in the molecule include esters of polyols such as triols with three or more propargyl acids. Propargylate compounds having three or more propargyl ester groups in the molecule are not particularly limited, but examples include polypropargyl esters such as trispropargyl ester and tetrakispropargyl ester. Examples of trispropargyl esters are not particularly limited, but include trimethylolpropane trispropargylate, trispropargylate-1,2,3-propanetriol, trispropargylate-1,2,4-butanetriol, and trispropargylate-1,2,6-hexanetriol.

[0041] The above-mentioned crosslinked resin is three-dimensionally crosslinked by (i) a condensation reaction between the acetoacetate ester group of an acetoacetate ester compound and a primary or secondary amino group of an amine compound to form a vinylogous urethane bond, or by a condensation reaction between the propagilate ester group of a propargyl ester ester compound and a primary amino group of an amine compound to form a vinylogous urethane bond. Crosslinked resins having vinylogoust urethane bonds are preferable from the viewpoint of having excellent mechanical strength and toughness, and a short time for resin decomposition. Furthermore, they are even more preferable because the bond exchange reaction proceeds even without a catalyst, eliminating the need for a step to uniformly disperse a catalyst during the production of the crosslinked resin and / or resin composition, and eliminating the need to worry about catalyst bleed-out over time when using anisotropic conductive films.

[0042] The reactions of vinylogous urethane include the formation of vinylogous urethane bonds, as well as amine exchange and hydrolysis, as shown below. Reversible dissociation and bonding are possible through the formation of vinylogous urethane bonds, amine exchange reactions, and hydrolysis reactions. In the reaction equations below, R1, R2, and R3 each independently represent arbitrary chemical structures. [ka]

[0043] The three-dimensional crosslinked structure (polymer network structure) formed by vinylogas urethane bonding is a robust structure, and therefore the crosslinked resin has excellent mechanical properties, heat resistance, and chemical resistance. Furthermore, stress relaxation and softening occur due to hydrolysis of the vinylogous urethane bond or amine exchange reaction with a monofunctional primary amine, so anisotropic conductive films using oligomers or polymers having vinylogous urethane bonds exhibit excellent disassembly properties.

[0044] In resin compositions containing a crosslinked resin having vinylogous urethane bonds, a catalyst may be added as needed to promote amine exchange reactions, reduce resin viscosity, and enhance self-healing properties. Examples of catalysts include sulfuric acid, p-toluenesulfonic acid, p-toluenesulfonic acid monohydrate, ethylphosphinic acid, phenylphosphinic acid, ethylphosphonic acid, phenylphosphonic acid, zinc(II) chloride, zinc(II) acetate, iron(II) chloride, iron(III) chloride, diethylamine, diisopropylamine, triethylamine, tributylamine, 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]non-5-yne, 1,5,7-triazabicyclo[4.4.0]deca-5-ene, ammonium chloride, ammonium acetate, and ammonium carbamates. The amount of catalyst added is preferably 0.1 to 6% by mass, more preferably 0.1 to 5% by mass, and even more preferably 0.1 to 3% by mass, relative to the total amount of crosslinked resin. When the amount of catalyst added is within the above range, the amine exchange reaction is appropriately controlled, and high mechanical properties and good self-healing properties tend to be obtained.

[0045] The method for producing a crosslinked resin having vinylogoust urethane bonds is not particularly limited, but for example, it can be produced by dissolving an acetoacetate ester compound, an amine compound, and optionally other monomers, as long as they do not contradict the purpose of the invention, in an organic solvent (e.g., methanol, ethanol, acetone, etc.), and then mixing and stirring them.

[0046] (Resin containing imine bonds) Resins having imine bonds as dynamic covalent bonds can be synthesized, for example, by referring to the method described in Polym. Chem. 7, 7052-7056 (2016). An example of a reversible reaction involving an imine bond is the imine-amine exchange reaction shown below. In the reaction equation below, R7, R8, and R9 each independently represent arbitrary chemical structures. [ka] A resin having imine bonds as dynamic covalent bonds can be obtained, for example, by a condensation reaction of an aldehyde compound or ketone compound having two or more carbonyl groups in the molecule, an amine compound having two or more primary amino groups in the molecule, and optionally other monomers that do not contradict the purpose of the invention.

[0047] Examples of amine compounds having two or more primary amino groups in their molecules include those similar to those listed above as raw materials for the synthesis of resins having VU bonds. Amine compounds having two or more primary amino groups in their molecules may be used individually or in combination of two or more types. Examples of aldehyde compounds having two or more carbonyl groups in their molecule include terephthalaldehyde, isophthalaldehyde, 2,5-diformylfuran, 3,4-diformylthiophene, 2,4-diformylimidazole, and 3,4-diccarboxyaldehyde pyrrole. Aldehyde compounds having two or more carbonyl groups in their molecule may be used individually or in combination of two or more. The amount of primary amino groups in monomer units derived from amine compounds having two or more primary amino groups in the molecule is preferably 1.01 to 1.50 equivalents, and more preferably 1.05 to 1.30 equivalents, relative to the amount of carbonyl groups in monomer units derived from aldehyde compounds or ketone compounds. When the amount of primary amino groups is within the above range, the density of the three-dimensional crosslinked structure formed by the condensation reaction between the carbonyl group of the aldehyde compound or ketone compound and the primary amino group of the amine compound is appropriately adjusted, and high mechanical properties and good fluidity tend to be obtained. A resin having imine bonds as dynamic covalent bonds can be produced, for example, by dissolving the above aldehyde compound or ketone compound, the above amine compound, and optionally other monomers within a range that does not contradict the purpose of the invention in an organic solvent (e.g., methanol, ethanol, etc.), and then mixing and stirring.

[0048] (Diketoenamine binding) A diketoenamine bond is a bond obtained, for example, by condensing a triketone compound and an amine compound, and reversible dissociation and bonding are possible through an exchange reaction involving an amino group. Resins having a diketoenamine bond as a dynamic covalent bond can be synthesized, for example, by referring to the method described in Nature Chemistry 11, 442-448 (2019). Specifically, an example of a reversible reaction of diketoenamine bonding is the diketoenamine-amine exchange reaction shown below. Note that in the reaction equation below, R 14 ~R 16 Each of these independently represents an arbitrary chemical structure. [ka]

[0049] (Other crosslinked resins with dynamic covalent bonds) Ester bonds are bonds obtained, for example, by curing a monomer that forms ester bonds during curing with optionally other monomers to produce a resin. Reversible dissociation and bonding are possible depending on reaction conditions such as catalysts, acids and bases, temperature, and transesterification reactions. A carbonate bond is a bond obtained, for example, by ring-opening polymerization of a biscyclic carbonate compound in the presence of a polyol and optionally other monomers to produce a resin, and it can be reversibly dissociated and bonded by carbonate exchange reactions or the like. These bonds can be reversibly dissociated and recombined depending on reaction conditions such as acid catalyst conditions and temperature.

[0050] Quaternary ammonium salt bonds are, for example, bonds obtained by crosslinking tertiary amines through alkylation, and reversible dissociation and bonding are possible due to the thermal equilibrium relationship of the crosslinking. Oxazoline bonds are, for example, bonds obtained by crosslinking 4,4-dimethyl-2-oxazolin-5-one molecules with bisphenol, and reversible dissociation and bonding are possible due to the thermal equilibrium relationship of the crosslinking.

[0051] Spiro-orthoester bonds are bonds obtained, for example, by crosslinking spiro-orthoesters together, and are reversibly dissociated and bonded depending on reaction conditions such as solvent and temperature. A borate ester bond is a bond obtained, for example, by crosslinking phenylboric acid with a diol, and can be reversibly dissociated and bonded depending on reaction conditions such as pH, acid-base ratio, and temperature. Disulfide bonds can be reversibly dissociated and bonded, for example, under the conditions of a redox reaction with a thiol.

[0052] Diels-Alder bonds are reactions that yield six-membered ring compounds from, for example, [4+2] cycloaddition reactions between various conjugated dienes and parent diene compounds, and generally react with good stereoselectivity and regioselectivity. Furthermore, if either or both of the conjugated diene or parent diene compound are stable, reversible dissociation and bonding are possible by the reverse reaction proceeding with heat.

[0053] (A skeleton derived from epoxy resin) The above-mentioned crosslinked resin may further have a skeleton derived from epoxy groups. Note that "having a skeleton derived from epoxy groups" means having a structure derived from a compound having epoxy groups in the crosslinked resin, or having a structure derived from a compound having epoxy groups in the skeleton of the crosslinked resin. When forming a crosslinked resin having dynamic covalent bonds, for example, a crosslinked resin containing an epoxy group-derived skeleton can be obtained by reacting a polyfunctional epoxy compound with other monomers (optionally, as long as they do not contradict the purpose of the invention) and a curing agent. Examples of polyfunctional epoxy compounds that can be used include glycidyl ether type epoxy compounds, glycidyl ester type epoxy compounds, glycidylamine type epoxy compounds, alicyclic epoxy compounds, and prepolymers obtained by polymerizing these compounds. As prepolymers, glycidyl ether type epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, alicyclic epoxy resins, etc., can be used at an appropriate degree of polymerization. Polyfunctional epoxy compounds may be used individually or in combination of two or more types.

[0054] Examples of glycidyl ether type epoxy compounds include bisphenol A diglycidyl ether, bisphenol AD ​​diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, hydroquinone diglycidyl ether, resocinol diglycidyl ether, biphenol diglycidyl ether, hexahydrobisphenol A diglycidyl ether, hexahydrobisphenol AD ​​diglycidyl ether, hexahydrobisphenol F diglycidyl ether, hexahydrobisphenol S diglycidyl ether, propanediol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, and cyclohexanediol diglycidyl ether. Examples include polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, tetrabromobisphenol A diglycidyl ether, bisphenol hexafluoroacetone diglycidyl ether, biphenyl diglycidyl ether, dihydroxynaphthalene diglycidyl ether, cresol novolac glycidyl ether, xylylene novolac glycidyl ether, bisphenol A novolac glycidyl ether, bisphenol F novolac diglycidyl ether, bisphenol S novolac glycidyl ether, triphenylmethane novolac glycidyl ether, biphenyl novolac glycidyl ether, terpene phenol novolac glycidyl ether, and derivatives thereof.

[0055] Examples of glycidyl ester type epoxy compounds include diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, triglycidyl benzenetricarboxylic acid, tetraglycidyl benzenetetracarboxylic acid, glycidyl trimellitic acid, glycidyl pyromellitic acid, and derivatives such as their anhydrides.

[0056] Examples of glycidylamine-type epoxy compounds include triglycidyl isocyanurate, tetraglycidyldiaminodiphenylmethane, tetraglycidylbenzenedimethaneamine, tetraglycidyldiaminodiphenyl ether, triglycidyldiaminodiphenylmethane, diglycidylaniline, diglycidylphenoxyaniline, diglycidylpiperazine, diglycidyltoluidine, diglycidylaminophenol, triglycidylaminophenol, diglycidylaminocresol, triglycidylaminocresol, and derivatives thereof.

[0057] Examples of alicyclic epoxy compounds include 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate, 3,4-epoxy-6methylcyclohexylmethyl-3',4'-epoxy-6methylcyclohexanecarboxylate, bis(3,4-epoxycyclohexylmethyl)adipate, bis(3,4-epoxy-6methylcyclohexylmethyl)adipate, ethyleneoxy-3,4-epoxycyclohexane, dicyclopentadiene diepoxide, cyclohexadiene diepoxide, cyclooctadiene diepoxide, and their derivatives.

[0058] Examples of curing agents include acid anhydrides and carboxylic acids, with carboxylic acid anhydrides and polycarboxylic acids being preferred. The hardening agent may be used alone or in combination of two or more types.

[0059] Examples of carboxylic acid anhydrides include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, 3-dodecenyl succinic anhydride, octenyl succinic anhydride, dodecyl succinic anhydride, maleic anhydride, methylnadic anhydride, chlorendicic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenonetetracarboxylic anhydride, ethylene glycol bis(anhydrotrimate), methylcyclohexenetetracarboxylic anhydride, polyazelaic anhydride, polysebacic anhydride, and ethylene glycol bisanhydrotrimellitate.

[0060] Examples of polycarboxylic acids include 1,2,3,4-butanetetracarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, cyclohexane-1,2-dicarboxylic acid, norbornane-2,3-dicarboxylic acid, as well as polyunsaturated fatty acids such as malonic acid, maleic acid, succinic acid, fumaric acid, glutaric acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, naphthalenedicarboxylic acid, naphthalentricarboxylic acid, and adipic acid, azelaic acid, sebacic acid, dimer acid, and trimer acid. The mixing ratio of the curing agent to the epoxy resin is preferably 0.4 mol or more and less than 1.0 mol, more preferably 0.5 mol or more and 0.9 mol or less, and even more preferably 0.5 mol or more and 0.8 mol or less, per 1 mol of epoxy groups in the epoxy resin. When the mixing ratio of the curing agent is within the above range, hydroxyl groups are present after polymerization, which tends to allow for efficient rearrangement of the polymer structure by dynamic covalent bonding.

[0061] The method for producing the resin composition of this embodiment is not particularly limited, but for example, it can be produced by mixing (a) conductive particles with the raw material monomers of the crosslinked resin (for example, an acetoacetic acid ester compound and an amine compound in the case of a vinylogous urethane bond). The mass ratio of (a) conductive particles to 100% of the total mass of the raw material monomer is preferably 0.0001 to 10% by mass, more preferably 0.001 to 1% by mass, and even more preferably 0.01 to 0.1% by mass.

[0062] <Other ingredients> The resin composition of this embodiment comprises (a) conductive particles and (b) a crosslinked resin having dynamic covalent bonds, and may optionally contain other components. The crosslinked resin content in the resin composition is not particularly limited, but is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, based on 100% by mass of the resin composition. When the crosslinked resin content is within the above range, scratch resistance, processability, self-healing properties, and adhesive properties tend to be better exhibited.

[0063] (thermoplastic resin) The resin composition of this embodiment may also contain, for example, a thermoplastic resin in addition to a crosslinked resin having dynamic covalent bonds as other components. Examples of the thermoplastic resins mentioned above include phenoxy resins, acrylic resins, methacrylic resins, polyvinyl acetal resins, polyimide resins, polyamide resins, polyamide-imide resins, polyphenylene oxide resins, polyethersulfone resins, polyester resins, polyethylene resins, polystyrene resins, polysulfone resins, polybutadiene resins, ABS resins, coumarone resins, and the like. The above thermoplastic resins may be used individually, or two or more types with different weight-average molecular weights may be used in combination, or one or more types may be used in combination with their prepolymers. Among these, it is preferable to include one or more selected from the group consisting of polyimide resins, polyamide resins, phenoxy resins, and coumarone resins.

[0064] The content of the thermoplastic resin in the resin composition of this embodiment is not particularly limited, but from the viewpoint of scratch resistance, it is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less, based on 100% by mass of the resin composition.

[0065] (Additives) In addition to the thermoplastic resin, this embodiment may also contain other additives such as flame retardants, antioxidants, light stabilizers, dispersants, lubricants, plasticizers, antistatic agents, pigments, dyes, stress reducers, defoamers, leveling agents, UV absorbers, foaming agents, ion scavengers, and rubber components. These additives may be used individually or in combination of two or more types.

[0066] The additive content in the resin composition of this embodiment is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less, based on 100% by mass of the resin composition. Furthermore, the lower limit of the additive content is not particularly limited and may be, for example, 0% by mass or more, 3% by mass or more, or 5% by mass or more. Furthermore, the additive content can be confirmed not only from the mixing ratio, but also by extracting the additive from the obtained film using a solvent, or by decomposing the film with a decomposition solution containing low molecular weight amines or alcohols, then extracting the additive and quantifying it using an analytical instrument such as liquid chromatography.

[0067] Examples of the above-mentioned pigments include inorganic pigments such as kaolin, synthetic iron oxide red, cadmium yellow, nickel titanium yellow, strontium yellow, hydrated chromium oxide, chromium oxide, cobalt aluminate, and synthetic ultramarine blue, as well as polycyclic pigments such as phthalocyanine and azo pigments.

[0068] Examples of the above-mentioned dyes include isoindolinone, isoindoline, quinophthalone, xanthene, diketopyrrolopyrrole, perylene, perinone, anthraquinone, indigoid, oxazine, quinacridone, benzimidazolone, violanthrone, phthalocyanine, azomethine, and the like.

[0069] Examples of the above-mentioned rubber components include one or more selected from the group consisting of butadiene rubber, acrylic rubber, and silicone rubber. The above-mentioned rubber components may be contained in a particulate form. Examples of such rubber particles include core-shell rubber particles, crosslinked acrylonitrile-butadiene rubber particles, crosslinked styrene-butadiene rubber particles, acrylic rubber particles, silicone particles, and the like.

[0070] (Physical properties of the resin composition) The resin composition of the present embodiment is not particularly limited as long as it contains (a) conductive particles and (b) a crosslinked resin having dynamic covalent bonds, but preferably has the following physical properties.

[0071] The storage elastic modulus E' at 23°C measured by the dynamic viscoelasticity measurement of the above resin composition is preferably 5.0×10 5 Pa or more from the viewpoint of adhesion, 5.0×10 5 Pa to 1.0×10 10 Pa, 7.0×10 5 Pa to 1.0×10 10 Pa, 1.0×10 6 Pa to 1.0×10 10 Pa, 1.2×10 6 Pa to 1.0×10 10 Pa, 1.4×10 6 Pa to 1.0×10 10 Pa, 1.6×10 6 Pa to 1.0×10 10 Pa, 1.8×10 6 Pa to 1.0×10 10 Pa, 2.0×10 6 Pa to 1.0×10 10 Pa, 2.2×10 6 Pa to 1.0×1010 Pa, 2.5 × 10 6 Pa~1.0×10 10 Pa, 3.0 × 10 6 Pa~1.0×10 10 Pa, 3.5 × 10 6 Pa~1.0×10 10 Pa, 3.8 × 10 6 Pa~9.0×10 9 Pa, 4.0 × 10 6 Pa~9.0×10 9 Pa, 5.0 × 10 6 Pa~8.0×10 9 Pa, 7.0 × 10 6 Pa~7.0×10 9 Pa or less, 9.0×10 6 Pa~6.0×10 9 Pa, 1.0 × 10 7 Pa~5.0×10 9 Pa, 1.2 × 10 7 Pa~3.0×10 9 Pa, 1.3 × 10 7 Pa~2.0×10 9 Pa, 1.4 × 10 7 Pa~1.0×10 9 Pa, 1.6 × 10 7 Pa~9.0×10 8 It can be Pa. The above storage modulus E' can be measured by the method described in the examples below.

[0072] The tanδ peak temperature in the dynamic viscoelasticity measurement of the above resin composition is preferably -20°C or higher, and can be -20°C to 130°C, -15°C to 130°C, or -10°C to 120°C, from the viewpoint of achieving superior adhesive strength, flexibility, and coating properties, as well as easier peeling by external triggers. The above tanδ peak temperature can be adjusted by the molecular weight of the crosslinked resin. Furthermore, in the case of a crosslinked resin that forms dynamic covalent bonds using amines as raw materials, it can also be adjusted by the ratio of diamine to trifunctional amine, etc. The tanδ peak temperature described above can be measured by the method described in the examples below.

[0073] The above resin composition preferably has a bond exchange temperature Tv. The bonding exchange temperature Tv of the above resin composition is preferably 50°C or higher from the viewpoint of easy disassembly, and can be 50°C to 150°C, 55°C to 150°C, 60°C to 140°C, 65°C to 130°C, or 65°C to 130°C. The above-mentioned coupling exchange temperature Tv can be measured by the method described in the examples below.

[0074] The gel fraction of the above resin composition is preferably 40% to 100% from the viewpoint of adhesive strength and durability, and can be 60% to 100%, 65% to 100%, 70% to 100%, 75% to 100%, 80% to 100%, 83% to 100%, or 87% to 100%. The above gel fraction can be adjusted by the molecular weight of the crosslinked resin. In the case of a crosslinked resin that forms dynamic covalent bonds using amines as raw materials, it can be adjusted by the amount of bifunctional or more amines, etc. The gel fraction described above can be measured by the method described in the examples below.

[0075] [Anisotropic conductive film] The anisotropic conductive film of this embodiment consists of the resin composition described above. The anisotropic conductive film of this embodiment preferably contains the resin composition of this embodiment described above, and more preferably consists only of the resin composition of this embodiment described above.

[0076] The average thickness of the anisotropic conductive film in this embodiment is preferably 5 μm to 100 μm, more preferably 6 μm to 50 μm, even more preferably 7 μm to 35 μm, and particularly preferably 8 μm to 20 μm.

[0077] The average width of the anisotropic conductive film in this embodiment is preferably 0.2 mm to 50 mm, more preferably 0.3 mm to 30 mm, even more preferably 0.4 mm to 25 mm, and particularly preferably 0.5 mm to 20 mm.

[0078] The length of the anisotropic conductive film in this embodiment is preferably 5m to 500m, more preferably 8m to 400m, even more preferably 10m to 300m, and particularly preferably 20m to 200m.

[0079] The elongation of the anisotropic conductive film of this embodiment in a tensile test at 23°C is preferably 10% or more from the viewpoint of excellent flexibility and ease of dismantling, and can be 10% to 1000%, 20% to 1000%, 30% to 900%, 40% to 800%, 45% to 700%, 50% to 600%, 55% to 500%, 60% to 400%, 65% to 300%, or 70% to 300% or less. The above elongation rate can be measured by the method described in the examples below.

[0080] The maximum stress measured in a tensile test at 23°C for the anisotropic conductive film of this embodiment is preferably 1 MPa or more, and can be 1 MPa to 100 MPa, 2 MPa to 100 MPa, 2.2 MPa to 100 MPa, or 2.5 MPa to 100 MPa or less, from the viewpoint of increasing adhesive strength. The above-mentioned maximum stress can be measured by the method described in the examples below.

[0081] The shear adhesive strength of the above-mentioned anisotropic conductive film, measured at a speed of 5 mm / min, is preferably 1 MPa or more from the viewpoint of firmly bonding the members, and can be 1 MPa to 60 MPa, 1.5 MPa to 60.0 MPa, 2.0 MPa to 50.0 MPa, 2.0 MPa to 50.0 MPa, 2.5 MPa to 40.0 MPa, 3.0 MPa to 35.0 MPa, or 3.5 MPa to 32.0 MPa. The above shear adhesive strength can be measured by the method described in the examples below.

[0082] [Anisotropic conductive film structure] The anisotropic conductive film of this embodiment may be an anisotropic conductive film structure further comprising a release film in contact with one surface of the anisotropic conductive film. Examples of the release film include films made of polyethylene, polypropylene, polystyrene, polyester (PET, PEN, etc.), polyamide, vinyl chloride, and polyvinyl alcohol. Among these, polypropylene and PET are preferred. It is preferable that the release film undergoes surface treatment such as fluorine treatment, Si treatment, or alkyd treatment. The film thickness of the release film is preferably 20 μm to 100 μm.

[0083] The anisotropic conductive film structure of this embodiment may further include a cover film in contact with the surface opposite to the surface of the anisotropic conductive film that is in contact with the release film. Having a cover film tends to further reduce the risk of foreign matter contamination during the manufacturing of the connecting structure described later. The cover film can be made of the same material and has the same film thickness as the release film described above.

[0084] [Manufacturing method for connecting structures] The method for manufacturing the connection structure in this embodiment is not particularly limited, as long as it includes the step of sandwiching the above-mentioned anisotropic conductive film between a circuit board and a circuit member having mutually opposing terminals, and applying heat and / or pressure to create electrical conductivity between the terminals of the circuit board and the terminals of the circuit member.

[0085] As a method for manufacturing the connection structure of this embodiment, a circuit board such as a glass substrate on which circuits and electrodes are formed by ITO wiring or metal wiring, and a circuit member such as an IC chip on which electrodes are formed at positions that are paired with the electrodes of the circuit board are prepared. The anisotropic conductive film of this embodiment is attached to the position on the circuit board where the circuit member will be placed. Then, the circuit board and the circuit member are aligned so that their respective electrodes are paired with each other, and then thermocompression bonding is performed. Thermocompression bonding is preferably performed at a temperature range of 80°C to 250°C for 1 second to 30 minutes. The pressure applied is preferably 0.1 MPa to 50 MPa relative to the area of ​​the circuit member.

[0086] [Disassembly method] The dismantling method of this embodiment is a method for dismantling a connecting structure having the anisotropic conductive film of this embodiment between a circuit board and a circuit member having mutually opposing terminals, and is not particularly limited as long as it includes (A) a step of heating, or heating and pressurizing, the anisotropic conductive film, and (B) a step of peeling the anisotropic conductive film from the circuit board or circuit member after step (A).

[0087] In the above dismantling method, it is preferable that the heating temperature in the heating or heating and pressurizing step is between the bond exchange temperature Tv+5°C and the bond exchange temperature Tv+30°C of the crosslinked resin having dynamic covalent bonds, as described above, from the viewpoint of easy dismantling and minimizing damage to the circuit board and circuit components after dismantling. Furthermore, (C) a step of cleaning the surface of the circuit board or circuit component after step (B) above is preferable from the viewpoint of making the circuit board or circuit component recyclable. [Examples]

[0088] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0089] [evaluation] The resin compositions and anisotropic conductive films obtained in the examples were measured and evaluated using the following methods.

[0090] (Storage modulus E', tanδ peak temperature, Tv in dynamic viscoelasticity measurements) Sheets of the resin composition with an average thickness of 300 μm, prepared in the following examples, were punched out to a size of 8 mm in diameter, set up in a dynamic viscoelasticity measuring device (ARES (TA Instruments)), and measured at a variable temperature from -50°C to 200°C under conditions of frequency 1 Hz and strain 0.2% to obtain the peak temperature (°C) of the storage modulus E' and tanδ at room temperature (23°C). The bond exchange temperature Tv (°C) was calculated by measuring the time (s) until the temperature became 1 / e under a 3.5% strain at three or more temperature levels, and then plotting Tv using an Arrhenius plot with ln(τ) on the vertical axis and 1 / T(K) on the horizontal axis.

[0091] (Gel fraction) Approximately 0.1 to 0.2 g of resin composition was taken from a sheet of resin composition with an average thickness of 300 μm prepared in the following example, wrapped in a mesh sheet, immersed in a butyl acetate / ethanol mixture (80 wt% / 20 wt%) for 24 hours, dried at 120°C for 2 hours, and the gel fraction was calculated as follows: Gel fraction = 100 × (weight of sample after drying) / (weight of sample before solvent addition).

[0092] (Elongation and maximum stress in tensile testing) Sheets of the resin composition with an average thickness of 60 μm, prepared in the following examples, were cut to a width of 10 mm and a length of 40 mm. These sheets were then set in a tensile testing machine with a grip distance of 20 mm, and measured at a temperature of 23°C and a speed of 20 mm / min to obtain the elongation (%) and maximum stress (i.e., maximum point strength, MPa).

[0093] (Shear adhesion) The shear adhesive strength was determined by the following method: (i) preparing a film, (ii) creating a sample for adhesive strength evaluation using the film, and (iii) evaluating the adhesive strength using the sample. (i) Film: The resins obtained in the examples and comparative examples were dried in a vacuum dryer at 80°C for 2 hours and at 160°C for 4 hours. The obtained resins were pulverized and pressed in a hot press (temperature setting: 160°C, pressure setting: 3MPa) for 25 minutes, then cut out to obtain a film of 60mm x 60mm x 0.2mm thickness. (ii) Sample for adhesive strength evaluation: The above film was sandwiched between two adherends (electrodeposited metal plates, product name "SPCC-SD 1.6*25*100 φ5-1 Laser Cationic Electrodeposited Coating (Black)", manufactured by Standard Test Piece Co., Ltd.) and secured with a binder clip. Subsequently, it was left to stand in a vacuum dryer and heated at 190°C for 1.5 hours to prepare the sample for measurement. (iii) Adhesion strength evaluation: The adhesive strength (MPa) was measured using an Instron 5967 material testing machine in accordance with JIS K6850. Note that this differs from JIS in that the bonding position is shifted because a Teflon spacer was inserted to equalize the thickness. In this test, adhesive strength can be evaluated as follows: excellent if 25 MPa or higher, good if 10 MPa or higher but less than 25 MPa, usable if 1 MPa or higher but less than 10 MPa, and unusable if less than 1 MPa.

[0094] [Example 1] (Manufacturing of crosslinked resins with dynamic covalent bonds) Ethylene glycol (18.6 g) and tert-butyl acetoacetate (100 g) were added to a 300 mL four-necked flask and stirred with a stirring blade under N2 flow. Then, the temperature was raised in an oil bath to an ambient temperature of 130°C, and the pressure inside the system was gradually reduced to 68 hPa. After heating and reducing the pressure for 4 hours, the unreacted tert-butyl acetoacetate was removed by distillation at an ambient temperature of 130°C and a reduced pressure of 3 hPa. After heating and reducing the pressure for 2 hours, the mixture was allowed to cool to room temperature and the bisacetoacetate ethylene glycol ester (EGAA) in the flask was recovered (66.3 g). Tris(2-aminoethyl)amine (0.64 g) and hexamethylenediamine (3.57 g) were dissolved in ethanol (10.6 mL). To this solution, the EGAA obtained above (8.0 g) and 0.005 g of conductive particles with an average particle size of 4 μm (manufactured by Sekisui Chemical Co., Ltd., trade name: Micropearl AU, hereinafter the same) were added and stirred. Before solidification, the mixture was coated onto a 38 μm thick PET film with a release treatment applied to the coating side using a bar coater and left to stand. After solidification, the film was dried in a vacuum dryer at 80°C for 2 hours and at 160°C for 4 hours to obtain a raw material of an anisotropic conductive film 1 with an average thickness of 25 μm made from resin composition 1. Sheets of resin composition 1 with average thicknesses of 60 μm and 300 μm were also prepared by the same method. Subsequently, the raw material was slit into strips 10 mm wide to obtain an anisotropic conductive film 1.

[0095] Using a sheet of the obtained resin composition 1, IR identification confirmed that it contains a crosslinked resin having VU bonds. The storage modulus E' of resin composition 1 at 23°C was 270 Pa, the tanδ peak temperature was 40°C, the bond exchange temperature Tv was 60°C, and the gel fraction was 90%. Furthermore, a sheet of the resin composition with an average thickness of 60 μm exhibited an elongation of 90% and a maximum stress of 13 MPa in a tensile test at 23°C. The shear adhesion strength was 22 MPa.

[0096] A 1.6mm x 15mm bare chip with 20μm x 100μm gold bumps arranged at a pitch of 40μm and an ITO (Indium Tin Oxide) glass substrate with a connection pitch corresponding to the bare chip were prepared. An anisotropic conductive film 1 was placed on the chip mounting position of the glass substrate and heated to 70°C and 5Kg / cm². 2 After applying heat and pressure for 2 seconds, the bare chip is aligned using a flip-chip bonder (FC2000 manufactured by Toray Engineering Co., Ltd., hereinafter the same) and temporarily attached to the predetermined position. Then, under constant heat conditions, it reaches 200°C after 2 seconds, and then maintains a constant temperature at 30 kg / cm². 2 Then, the bare chip and the ITO glass substrate were heated and pressurized for 10 seconds to connect them and obtain a connecting structure.

[0097] Conduction resistance measurements were performed on the above-mentioned connection structure using 64 pairs of daisy-chain circuits formed by connected bare chips and ITO glass electrodes, and insulation resistance measurements were performed using 40 pairs of comb-type electrodes. The results showed that the conduction resistance, including wiring resistance, was 2.7 kΩ, indicating that all 64 pairs of electrodes were connected. On the other hand, the insulation resistance was 10 9 The resistance was greater than Ω, and no short circuits occurred between the 40 pairs of comb-shaped electrodes. Furthermore, after applying a 10V DC voltage to the comb-shaped electrode section and leaving it for 1000 hours under conditions of 85°C and 85% relative humidity, the continuity resistance and insulation resistance were measured in the same manner. The results showed that the continuity resistance was 2.9kΩ and the insulation resistance was 8.2×10⁻⁶. 8 The impedance was Ω, and there were no problems with connection reliability or insulation reliability, making it useful in fine-pitch connections.

[0098] The above connecting structure was heated at 80°C (Tv of resin composition 1 + 20°C) for 10 minutes, and the anisotropic conductive film 1 was peeled off from the bare chip and the ITO glass substrate. Because the adhesive strength had sufficiently decreased due to heating, the anisotropic conductive film 1 could be easily peeled off by hand.

[0099] [Comparative Example 1] As a resin that does not have dynamic covalent bonds, 78 parts by mass of phenoxy resin (manufactured by Toto Chemical Co., Ltd., trade name: Phenotote YP50, hereinafter the same), 23 parts by mass of naphthalene-type epoxy resin (manufactured by Dainippon Ink and Chemicals, Inc., trade name: HP4032D, hereinafter the same), 0.5 parts by mass of silane coupling agent (manufactured by Nippon Unicar Co., Ltd., trade name: A-187, hereinafter the same), and 300 parts by mass of ethyl acetate were mixed to obtain a varnish. This varnish was applied to a 38 μm PET film that had been released using a blade coater, and the solvent was dried off to obtain a 2 μm thick anisotropic conductive film 2.

[0100] A 1.6mm x 15mm bare chip with 20μm x 100μm gold bumps arranged at a 40μm pitch and an ITO (Indium Tin Oxide) glass substrate with a connection pitch corresponding to the bare chip were prepared. An anisotropic conductive film 2 was placed on the chip mounting position of the glass substrate and heated at 60°C and 5Kg / cm². 2 The bare chips were heat-pressed for 2 seconds, then aligned using a flip-chip bonder (FC2000 manufactured by Toray Engineering Co., Ltd., hereafter the same), temporarily attached to the designated position, and then heated under constant heat conditions to reach 200°C after 2 seconds, and then maintained at a constant temperature of 30 kg / cm². 2 Then, the bare chip and the ITO glass substrate were heated and pressurized for 10 seconds to connect them and obtain a connecting structure.

[0101] Regarding the above-mentioned connection structure, we attempted to peel the anisotropic conductive film 2 from the bare chip and ITO glass substrate after heating it at 80°C for 10 minutes. However, it could not be easily peeled off by hand, and excessive force was applied in an attempt to peel it off, resulting in the destruction of either the bare chip, the ITO glass substrate, or the anisotropic conductive film 2. [Industrial applicability]

[0102] The present invention provides a resin composition that achieves both connection reliability and ease of disassembly, and an anisotropic conductive film made from the resin composition. Furthermore, it provides a method for manufacturing a connection structure using the anisotropic conductive film and a method for disassembling the connection structure. This makes it suitable for fine-pitch connection applications, such as connecting liquid crystal displays to TCP, TCP to FPC, FPC to printed circuit boards, or flip-chip mounting where semiconductor chips are directly mounted onto a substrate.

Claims

1. (a) conductive particles, and (b) Crosslinked resin having dynamic covalent bonds, A resin composition containing the following:

2. The resin composition according to claim 1, wherein the crosslinked resin having dynamic covalent bonds further comprises a skeleton derived from epoxy groups.

3. The resin composition according to claim 1, wherein the dynamic covalent bond is any one of a vinylogous urethane bond, a vinylogous urea bond, a vinylogous amide bond, an imine bond, or a diketoenamine bond.

4. The storage modulus E' at 23°C in dynamic viscoelasticity measurements was 5.0 × 10⁻⁶. ５ Pa ~ 1.0 × 10 １０ The resin composition according to claim 1, wherein the material is Pa.

5. The resin composition according to claim 1, wherein the tanδ peak temperature in dynamic viscoelasticity measurement is -20°C to 130°C.

6. The resin composition according to claim 1, wherein the bond exchange temperature Tv is 50°C to 150°C.

7. The resin composition according to claim 1, wherein the gel fraction is 40% to 100%.

8. An anisotropic conductive film comprising the resin composition according to any one of claims 1 to 7.

9. An anisotropic conductive film according to claim 8, having an average thickness of 5 μm to 100 μm, an average width of 0.2 mm to 50 mm, and a length of 5 m to 500 m.

10. The anisotropic conductive film according to claim 8, wherein the elongation in a tensile test at 23°C is 10% to 1000%.

11. The anisotropic conductive film according to claim 8, wherein the maximum stress in a tensile test at 23°C is 1 MPa to 100 MPa.

12. The anisotropic conductive film according to claim 8, wherein the shear adhesive strength is 1 MPa to 60 MPa.

13. An anisotropic conductive film structure comprising an anisotropic conductive film according to claim 8 and a release film in contact with one side of the anisotropic conductive film.

14. The anisotropic conductive film structure according to claim 13, further comprising a cover film in contact with the side of the anisotropic conductive film opposite to the one side thereof.

15. A method for manufacturing a connection structure, comprising the steps of sandwiching an anisotropic conductive film according to claim 8 between a circuit board and a circuit member having mutually opposing terminals, and applying heat and / or pressure to create electrical conductivity between the terminals of the circuit board and the terminals of the circuit member.

16. A method for disassembling a connection structure having an anisotropic conductive film according to claim 8 between a circuit board and a circuit member having mutually opposing terminals, (A) A step of heating or heating and pressurizing the anisotropic conductive film, (B) A step of peeling off the anisotropic conductive film from the circuit board or circuit member after step (A), Demolition methods, including those mentioned above.

17. The demolition method according to claim 16, wherein the heating temperature in the heating or heating and pressurizing step is (b) the bond exchange temperature Tv + 5°C or higher and the bond exchange temperature Tv + 30°C or lower of the bond exchange temperature of the crosslinked resin having dynamic covalent bonds.

18. (C) The dismantling method according to claim 16, further comprising the step of cleaning the surface of a circuit board or circuit member after step (B).

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