Epoxy resin composition, film, method for producing film, and cured product

Abstract

An epoxy resin composition comprising: component (A): an epoxy resin, component (B): a microcapsule type curing agent, component (C): a reactive diluent, and component (D): a compound represented by the following formula (1). (In formula (1), X1 has 2 or more and 5 or less consecutive carbon-carbon bonds, the substituent of the carbon included in X1 and R1 to R5 are each one selected from the group consisting of hydrogen, an alkyl group, an unsaturated aliphatic group, an aromatic group, a substituent including a hetero atom, a substituent including a halogen atom, and a halogen atom. The substituent of the carbon included in X1 and R1 to R5 are each optionally the same as or different from each other. And the compound represented by formula (1) is optionally a fused ring compound in which any of R1 to R5 is present in the same ring.)

Description

Technical Field

[0001] This invention relates to epoxy resin compositions, films, methods for manufacturing films, and cured products. Background Technology

[0002] Epoxy resin has long been used in a wide range of applications, including as an insulating material, sealing material, adhesive, conductive material, matrix resin for fiber-reinforced plastics, and impregnation fixative for motor coils in electrical and electronic components.

[0003] Recent demands on electronic devices have evolved to include miniaturization, high functionality, lightweight design, and multi-functionality. In semiconductor chip mounting technology, further miniaturization, high density, and micro-scale production are achieved through reducing the spacing between electrode pads. Furthermore, the enlargement of semiconductor chips is also underway. Within the gap between the semiconductor chip and the substrate, an underfill material protects the bump connections and the chip's circuitry. Epoxy resin compositions can be used as this underfill material.

[0004] As epoxy resin compositions applicable to underfill materials, for example, one-component epoxy resin compositions are disclosed, which contain microencapsulated amine / epoxy adduct particles and reactive diluents, and have excellent storage stability, curing characteristics, cured product properties and low viscosity (see, for example, Patent Document 1).

[0005] In addition, a single-component epoxy resin composition is disclosed, which includes a microencapsulated curing agent with an epoxy resin curing agent containing two or more amine compounds as the core, and a thermosetting liquid resin with a viscosity of 0.03 Pa·s or more and less than 3 Pa·s at 25°C, and has excellent storage stability, low-temperature curing and gap penetration (see, for example, Patent Document 2).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent No. 3454437

[0009] Patent Document 2: Japanese Patent No. 6085130 Summary of the Invention

[0010] The problem the invention aims to solve

[0011] In recent years, regarding underfill materials for the gaps between semiconductor chips and substrates, as a countermeasure against the large area resulting from the increasing size of semiconductor chips and the narrow gaps associated with the miniaturization of semiconductor chips, there has been a search for low viscosity materials that can achieve sufficient penetration in a short time. Furthermore, regarding the aforementioned underfill materials, in order to reduce the impact on the constituent components of the semiconductor chip, there has been a search for low-temperature curing properties, such as sufficient curing at around 100°C.

[0012] Furthermore, from the perspective of improving productivity, the aforementioned bottom filler material is required to be a one-component epoxy resin composition that can eliminate the mixing process during use. However, since the epoxy resin and curing agent in the one-component epoxy resin composition are integrated, high storage stability is required.

[0013] That is, to seek a single-component epoxy resin composition that simultaneously possesses low viscosity, sufficient curing at around 100°C, and high storage stability at a high level.

[0014] Furthermore, with the miniaturization and thinning of electronic materials in recent years, the importance of films obtained using epoxy resin compositions is increasing for the purpose of reducing the thickness of adhesive and insulating layers. To obtain such films, a coating solution is prepared by dissolving components such as epoxy resin, curing agent, curing accelerator, and a film-forming polymer in a solvent. This coating solution is then applied to a specified support, followed by drying to produce the film. Therefore, there is a strong demand for the storage stability of the coating solution, the stability during the film manufacturing process of applying and drying the coating solution, and the stability of the film in its final state.

[0015] Regarding the various requirements for epoxy resin compositions mentioned above, the single-component epoxy resin compositions disclosed in Patent Documents 1 and 2 have the following problems: there is room for improvement in balancing curing properties and storage stability; furthermore, there is room for improvement in the stability of films obtained using these epoxy resin compositions during the manufacturing process and in the film state.

[0016] Therefore, in view of the problems of the prior art described above, the present invention aims to obtain an epoxy resin composition that simultaneously exhibits low viscosity, sufficient curability at around 100°C, and excellent storage stability, and to provide an epoxy resin composition that provides excellent stability of films obtained using the epoxy resin composition during the manufacturing process and in the film state.

[0017] Solution for solving the problem

[0018] Through in-depth research, the inventors discovered that the above-mentioned objectives can be achieved through the following technical means, thus completing this invention.

[0019] That is, the present invention is as follows.

[0020] [1] An epoxy resin composition comprising:

[0021] Component (A): Epoxy resin,

[0022] Component (B): Microencapsulated curing agent,

[0023] Ingredient (C): Reactive diluent, and

[0024] Component (D): The compound shown in formula (1) below.

[0025]

[0026] (In formula (1), X1 has two or more but no more than five consecutive carbon-carbon bonds, and the carbon substituents in X1 and R1 to R5 are selected from the group consisting of hydrogen, alkyl, unsaturated aliphatic groups, aromatic groups, substituents containing heteroatoms, substituents containing halogen atoms, and halogen atoms. The carbon substituents in X1 and R1 to R5 may be the same or different from each other. And the compound shown in formula (1) may optionally be a fused-ring compound selected from any of R1 to R5 existing in the same ring.)

[0027] [2] The epoxy resin composition according to [1] above, wherein the aforementioned component (D) is a compound represented by the following formula (2).

[0028]

[0029] (In formula (2), X2 has two or more but no more than four consecutive carbon-carbon bonds, and the carbon substituents in X2 and R1 to R5 are selected from the group consisting of hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatoms, substituent containing halogen atoms, and halogen atoms. The carbon substituents in X2 and R1 to R5 may be the same or different from each other. And the compound shown in formula (2) may be a fused ring compound selected from any of R1 to R5 existing in the same ring.)

[0030] [3] The epoxy resin composition according to [1] or [2] above, wherein the aforementioned component (D) is a compound represented by the following formula (3).

[0031]

[0032] In formula (3), R1 to R9 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatom, substituent containing halogen atom and halogen atom.

[0033] R1 to R9 may be chosen to be the same or different from each other. The compound shown in formula (3) may be a fused-ring compound selected from any of R1 to R5 that exists in the same ring.

[0034] [4] The epoxy resin composition according to any one of [1] to [3] above, wherein the aforementioned component (D) is a compound represented by the following formula (4).

[0035]

[0036] In formula (4), R1 to R8 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatom, substituent containing halogen atom and halogen atom.

[0037] R1 to R8 may be chosen to be the same or different from each other. The compound shown in formula (4) may be a fused-ring compound selected from any of R1 to R5 that exists in the same ring.

[0038] [5] The epoxy resin composition according to any one of [1] to [4] above, wherein the aforementioned component (A) epoxy resin contains at least bisphenol F type epoxy resin.

[0039] [6] The epoxy resin composition according to any one of [1] to [5] above, wherein the roundness of the core of the microcapsule-type curing agent of the aforementioned component (B) is 0.93 or more.

[0040] [7] The epoxy resin composition according to any one of [1] to [6] above, wherein the reactive diluent of the aforementioned component (C) is a compound having an aromatic ring.

[0041] [8] The epoxy resin composition according to any one of [1] to [7] above, wherein the aforementioned component (C) reactive diluent is a compound with a monocyclic and monofunctional aromatic ring.

[0042] [9] The epoxy resin composition according to any one of [1] to [8] above, wherein the content of the reactive diluent of the aforementioned component (C) in the aforementioned epoxy resin composition is more than 1% by mass and less than 20% by mass.

[0043]

[10] The epoxy resin composition according to any one of [1] to [9] above, wherein the content of the aforementioned component (D) in the aforementioned epoxy resin composition is 0.001% by mass or more and 5% by mass or less.

[0044]

[11] The epoxy resin composition according to any one of [1] to

[10] above, wherein the aforementioned R1 to R5 are free of epoxy groups and the structure of the following formula (5) (terminal diol).

[0045]

[0046]

[12] A thin film having:

[0047] Support body; and

[0048] A resin composition layer formed on the aforementioned support and comprising any one of the epoxy resin compositions described in [1] to

[11] .

[0049]

[13] The film according to

[12] above, wherein the aforementioned resin composition layer further comprises component (E): a polymer for film formation.

[0050]

[14] The film according to

[12] or

[13] above, wherein the aforementioned film is selected from any one of the group consisting of interlayer insulating film, thin film solder resist, sealing sheet, conductive film, anisotropic conductive film and thermally conductive film.

[0051]

[15] A method for manufacturing a thin film, comprising the steps described in any one of

[12] to

[14] above:

[0052] After coating the aforementioned support with an epoxy resin composition comprising at least any one of the aforementioned [1] to

[11] and an organic solvent of component (F), the aforementioned organic solvent of component (F) is dried at a temperature range of 50 to 160°C for a time range of 1 to 30 minutes.

[0053]

[16] A cured product, which is a cured product of the epoxy resin composition described in any one of [1] to

[11] above.

[0054]

[17] A cured product, which is a cured product of the film described in any one of

[12] to

[14] above.

[0055] The effects of the invention

[0056] According to the present invention, an epoxy resin composition can be provided that has low viscosity, sufficient curability at around 100°C, excellent storage stability, and excellent stability in the film manufacturing process and in the film state when applied to a film. Detailed Implementation

[0057] Hereinafter, a detailed description will be given of the method for carrying out the present invention (hereinafter referred to as "this embodiment").

[0058] The following embodiments are illustrative of the present invention and do not imply that the present invention is limited to the following content. The present invention can be implemented with appropriate modifications within its scope.

[0059] [Epoxy Resin Composition]

[0060] The epoxy resin composition of this embodiment comprises:

[0061] Component (A): Epoxy resin,

[0062] Component (B): Microencapsulated curing agent,

[0063] Component (C): Reactive diluent, and

[0064] Component (D): The compound shown in formula (1) below.

[0065]

[0066] In formula (1), X1 has two or more but no more than five consecutive carbon-carbon bonds, and the carbon substituents in X1 and R1 to R5 are selected from the group consisting of hydrogen, alkyl, unsaturated aliphatic groups, aromatic groups, substituents containing heteroatoms, substituents containing halogen atoms, and halogen atoms. The carbon substituents in X1 and R1 to R5 may be the same or different from each other. The compound shown in formula (1) is optionally a fused-ring compound selected from any of R1 to R5 existing in the same ring.

[0067] (Component (A): Epoxy resin)

[0068] The epoxy resin composition of this embodiment includes component (A): epoxy resin (hereinafter sometimes referred to as (A) epoxy resin, component (A)).

[0069] As for (A) epoxy resin, it is not limited to the following substances, but may include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, tetrabromobisphenol A type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, tetrabromobiphenyl type epoxy resin, diphenyl ether type epoxy resin, benzophenone type epoxy resin, phenylbenzoate type epoxy resin, diphenyl sulfide type epoxy resin, diphenyl sulfoxide type epoxy resin, diphenyl sulfone type epoxy resin, diphenyl disulfide type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, hydroquinone type epoxy resin, methyl hydroquinone type epoxy resin, and dibutyl hydroquinone type epoxy resin. Difunctional epoxy resins such as oxygen-containing epoxy resins, resorcinol-type epoxy resins, methylresorcinol-type epoxy resins, and catechol-type epoxy resins; trifunctional epoxy resins such as N,N-diglycidylaminobenzene-type epoxy resins and triazine-type epoxy resins; tetrafunctional epoxy resins such as tetraglycidyldiaminodiphenylmethane-type epoxy resins and diaminobenzene-type epoxy resins; multifunctional epoxy resins such as phenol-formaldehyde varnish-type epoxy resins, cresol-formaldehyde varnish-type epoxy resins, triphenylmethane-type epoxy resins, tetraphenylethane-type epoxy resins, dicyclopentadiene-type epoxy resins, naphthol-aralkyl-type epoxy resins, and brominated phenol-formaldehyde varnish-type epoxy resins; and alicyclic epoxy resins.

[0070] They can be used individually or in combination of two or more. Furthermore, they can also be used in combination with epoxy resins obtained by modifying them with isocyanates, etc.

[0071] In the epoxy resin composition of this embodiment, from the viewpoint of processability and heat resistance, it is preferable to include a bisphenol type epoxy resin; from the viewpoint of imparting storage stability and good reactivity, it is more preferable to include a bisphenol F type epoxy resin; and from the viewpoint of imparting sufficient mechanical properties, it is even more preferable to further include a bisphenol A type epoxy resin.

[0072] Furthermore, by including bisphenol A type epoxy resin in addition to bisphenol F type epoxy resin, superior storage stability and good reactivity are exhibited. This mechanism is not intended to be limited to this, but can be considered as follows: By including bisphenol A type epoxy resin, the aggregation of bisphenol F type epoxy resin is suppressed. Therefore, the uniformity of the epoxy resin composition of this embodiment is improved, storage stability is enhanced, and molecular diffusivity after curing begins is improved, thereby increasing reactivity.

[0073] When using bisphenol F type epoxy resin and bisphenol A type epoxy resin in combination, from the viewpoint of fully exhibiting the above-mentioned effects, the amount of bisphenol F type epoxy resin added is preferably 5 parts by mass or more, more preferably 15 parts by mass or more, further preferably 25 parts by mass or more, even more preferably 30 parts by mass or more, and even more preferably 40 parts by mass or more, relative to a total of 100 parts by mass of bisphenol F type epoxy resin and bisphenol A type epoxy resin. Furthermore, from the viewpoint of adding bisphenol A type epoxy resin to exhibit sufficient mechanical properties, the amount of bisphenol F type epoxy resin added is preferably 90 parts by mass or less, more preferably 85 parts by mass or less, and even more preferably 80 parts by mass or less.

[0074] From the viewpoint of obtaining an epoxy resin composition with excellent electrical properties and a good balance between curability and storage stability, (A) the total chlorine content in the epoxy resin is preferably 2500 ppm or less, more preferably 2000 ppm or less, even more preferably 1500 ppm or less, and even more preferably 900 ppm or less.

[0075] Furthermore, from the viewpoint of achieving the specified technical significance, (A) the total chlorine content contained in the epoxy resin is preferably 0.01 ppm or more, more preferably 0.02 ppm or more, even more preferably 0.05 ppm or more, even more preferably 0.1 ppm or more, even more preferably 0.2 ppm or more, and particularly preferably 0.5 ppm or more.

[0076] Here, the total chlorine content in (A) epoxy resin represents the total amount of organic and inorganic chlorine contained in (A) epoxy resin, and is a mass reference value relative to (A) epoxy resin.

[0077] (A) The total chlorine content of epoxy resin was determined using the following method.

[0078] For epoxy resin (A), xylene is used for washing, and the process is repeated with filtration until no epoxy resin remains in the xylene used as the washing solution. Then, the filtrate is distilled off under reduced pressure below 100°C to obtain the epoxy resin. A sample of the obtained epoxy resin, weighed precisely in a titration volume of 3–7 mL, is dissolved in 25 mL of ethylene glycol monobutyl ether. 25 mL of a propylene glycol solution containing 1 equivalent of KOH is added, and after boiling for 20 minutes, titration is performed with an aqueous solution of silver nitrate. The titration volume can be used to calculate the epoxy resin composition.

[0079] Here, the chlorine contained in the 1,2-chlorool group of the total chlorine is generally referred to as hydrolyzable chlorine. The amount of hydrolyzable chlorine in (A) the epoxy resin is preferably 100 ppm or less, more preferably 50 ppm or less, further preferably 0.01 ppm or more and 20 ppm or less, and even more preferably 0.05 ppm or more and 10 ppm or less. If the amount of hydrolyzable chlorine in (A) the epoxy resin is 100 ppm or less, it is advantageous from the viewpoint of achieving both high curability and storage stability in the epoxy resin composition of this embodiment, and there is a tendency for the cured epoxy resin composition of this embodiment to exhibit excellent electrical properties.

[0080] Here, (A) the hydrolytic chlorine in the epoxy resin is determined by the following method.

[0081] Dissolve 3g of the sample in 50mL of toluene, add 20mL of methanol solution containing 0.1 equivalent of KOH, boil for 15 minutes, and then titrate with silver nitrate aqueous solution. The titration amount can be calculated from the titration amount obtained.

[0082] (Component (B): Microencapsulated curing agent)

[0083] The epoxy resin composition of this embodiment includes component (B): microencapsulated curing agent (hereinafter sometimes referred to as (B) microencapsulated curing agent, component (B)).

[0084] (B) Microencapsulated curing agents refer to curing agents that have at least a core containing curing agent components and a shell covering the aforementioned core. By making component (B) microencapsulated, the curing agent components are physically isolated from the aforementioned (A) epoxy resin, component (C) (reactive diluent) and component (D) (specified compound) through a capsule membrane, thus exhibiting a tendency for excellent storage stability.

[0085] <Nuclear>

[0086] The core of the (B) microencapsulated curing agent can be any curing agent used in epoxy resin, without particular limitation. Examples include amine-based curing agents, amide-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, catalyst-type curing agents, and their modifiers. One type can be used alone, or two or more types can be used in combination.

[0087] As an amine-based curing agent, it is not limited to the following substances, but can include, for example, amine adduct systems, modified polyamine systems, aliphatic polyamine systems, heterocyclic polyamine systems, alicyclic polyamine systems, aromatic amine systems, polyamide amine systems, ketimine systems, carbamate amine systems, etc.

[0088] As an amide-based curing agent, it is not limited to the following substances, but can be listed as, for example, dicyandiamide and guanidine compounds as its derivatives, compounds obtained by adding anhydrides to amine compounds, and hydrazide compounds.

[0089] As an acylhydrazine compound, it is not limited to the following substances, but can be listed as such as succinic dihydrazine, adipic dihydrazine, phthalic dihydrazine, isophthalic dihydrazine, terephthalic dihydrazine, p-hydroxybenzoic dihydrazine, salicylic dihydrazine, phenylaminopropionic dihydrazine, maleic dihydrazine, etc.

[0090] As guanidine compounds, they are not limited to the following substances, but can include, for example, dicyandiamide, methylguanidine, ethylguanidine, propylguanidine, butylguanidine, dimethylguanidine, trimethylguanidine, phenylguanidine, diphenylguanidine, toluene-methylguanidine, etc.

[0091] As a phenolic curing agent, it is not limited to the following substances, but can include, for example, phenolic varnish resin, cresol varnish resin, phenol aralkyl resin, cresol aralkyl resin, naphthol aralkyl resin, biphenyl-modified phenolic resin, biphenyl-modified phenol aralkyl resin, dicyclopentadiene-modified phenolic resin, aminotriazine-modified phenolic resin, naphthol varnish resin, naphthol-phenol co-condensed phenolic varnish resin, naphthol-cresol co-condensed phenolic varnish resin, allyl acrylic phenolic resin, etc.

[0092] As an anhydride-based curing agent, it is not limited to the following substances, but can be listed as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, etc.

[0093] As a catalyst-type curing agent, it is not limited to the following substances, but can be listed as cationic thermosetting catalysts, BF3-amine complexes, etc.

[0094] Among the various curing agents constituting the core, from the viewpoint of having moderate reactivity, amine-based curing agents containing low-molecular-weight amine compounds (a1) and amine adducts are preferred.

[0095] Examples of low-molecular-weight amine compounds (a1) constituting amine-based curing agents include compounds having at least one primary amino group and / or a secondary amino group but no tertiary amino group, and compounds having at least one tertiary amino group and at least one active hydrogen group.

[0096] The term "compound having at least one primary amino group and / or secondary amino group but not a tertiary amino group" as mentioned above is not limited to the following substances, but may include, for example, primary amines that do not have a tertiary amino group, such as methylamine, ethylamine, propylamine, butylamine, ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, ethanolamine, propanolamine, cyclohexylamine, isophorone diamine, aniline, toluidine, diaminodiphenylmethane, diaminodiphenyl sulfone, etc.; and secondary amines that do not have a tertiary amino group, such as dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, diethanolamine, diethanolamine, dipropanolamine, dicyclohexylamine, piperidine, piperidone, diphenylamine, phenylmethylamine, phenylethylamine, etc.

[0097] The term "compound having at least one tertiary amino group and at least one active hydrogen group" as used above is not limited to the following substances, but may include, for example, amino alcohols such as 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, methyldiethanolamine, triethanolamine, and N-β-hydroxyethylmorpholine; aminophenols such as 2-(dimethylaminomethyl)phenol and 2,4,6-tris(dimethylaminomethyl)phenol; and 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, and 2-heptadecylimidazole. Imidazoles such as 2-phenylimidazolium, 1-aminoethyl-2-methylimidazolium, 1-(2-hydroxy-3-phenoxypropyl)-2-methylimidazolium, 1-(2-hydroxy-3-phenoxypropyl)-2-ethyl-4-methylimidazolium, 1-(2-hydroxy-3-butoxypropyl)-2-methylimidazolium, and 1-(2-hydroxy-3-butoxypropyl)-2-ethyl-4-methylimidazolium; and imidazolines such as 1-(2-hydroxy-3-phenoxypropyl)-2-phenylimidazoline, 1-(2-hydroxy-3-butoxypropyl)-2-methylimidazoline, 2-methylimidazoline, 2,4-dimethylimidazoline, 2-ethylimidazoline, and 2-ethyl-4-methylimidazoline. Imidazolinides, including 2-benzylimidazoline, 2-phenylimidazoline, 2-(o-tolyl)-imidazoline, tetramethylene-bisimizoline, 1,1,3-trimethyl-1,4-tetramethylene-bisimizoline, 1,3,3-trimethyl-1,4-tetramethylene-bisimizoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-4-methylimidazoline, 1,2-phenylene-bisimizoline, 1,3-phenylene-bisimizoline, 1,4-phenylene-bisimizoline, 1,4-phenylene-bis-4-methylimidazoline, etc.; dimethylaminopropylamine, Tertiary aminoamines such as diethylaminopropylamine, dipropylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, N-methylpiperazine, N-aminoethylpiperazine, and diethylaminoethylpiperazine; aminothiols such as 2-dimethylaminoethanethiol, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptopyridine, and 4-mercaptopyridine; aminocarboxylic acids such as N,N-dimethylaminobenzoic acid, N,N-dimethylglycine, nicotinic acid, isonicotinic acid, and methylpyridinecarboxylic acid; and aminohydrazides such as N,N-dimethylglycine hydrazide, nicotinic acid hydrazide, and isonicotinic acid hydrazide.

[0098] Among these low-molecular-weight amine compounds (a1), imidazoles are preferred from the viewpoint of having moderate reactivity.

[0099] Next, examples of amine adducts constituting amine-based curing agents include compounds with amino groups obtained by reacting carboxylic acid compounds, sulfonic acid compounds, urea compounds, isocyanate compounds, epoxy resins (e1) with amine compounds (a2).

[0100] As a carboxylic acid compound, it is not limited to the following substances, but can be listed as succinic acid, adipic acid, sebacic acid, phthalic acid, dimer acid, etc.

[0101] As a sulfonic acid compound, it is not limited to the following substances, but can be listed as ethanesulfonic acid, p-toluenesulfonic acid, etc.

[0102] As a urea compound, it is not limited to the following substances, but can be listed as urea, methylurea, dimethylurea, ethylurea, tert-butylurea, etc.

[0103] As isocyanate compounds, they are not limited to the following substances, but can include, for example, aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, aliphatic triisocyanates, polyisocyanates, etc.

[0104] As an aliphatic diisocyanate, it is not limited to the following substances, but can be listed as ethylene diisocyanate, propylene diisocyanate, butyl diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc.

[0105] As an alicyclic diisocyanate, it is not limited to the following substances, but can be listed as such as isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, norbornene diisocyanate, 1,4-isocyanoylcyclohexane, 1,3-bis(isocyanomethyl)cyclohexane, 1,3-bis(2-isocyanopropyl-2-yl)cyclohexane, etc.

[0106] As an aromatic diisocyanate, it is not limited to the following substances, but can be listed as toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate, 1,5-naphthalene diisocyanate, etc.

[0107] As an aliphatic triisocyanate, it is not limited to the following substances, but can be listed as, for example, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyl octane, 1,3,6-triisocyanate methyl hexane, etc.

[0108] As for polyisocyanates, they are not limited to the following substances, but may include polymethylene polyphenyl polyisocyanates, polyisocyanates derived from the aforementioned diisocyanate compounds, etc. As for polyisocyanates derived from the aforementioned diisocyanate compounds, may include isocyanurate-type polyisocyanates, biuret-type polyisocyanates, carbamate-type polyisocyanates, urethane-type polyisocyanates, carbodiimide-type polyisocyanates, etc.

[0109] Examples of epoxy resins (e1) include compounds described in ((A) epoxy resin) above.

[0110] As the amine compound (a2), the amine compound listed as an example of a low-molecular-weight amine compound (a1) constituting the above-mentioned amine-based curing agent can be used.

[0111] Among these amine adducts, those obtained by reacting an epoxy resin (e1) with an amine compound (a2) are particularly preferred. Amine adducts obtained by reacting an epoxy resin (e1) with an amine compound (a2) are also preferred from the viewpoint that unreacted amine compound (a2) can be appropriated as a low-molecular-weight amine compound (a1).

[0112] From the viewpoint of preservation stability, (B) the core component of the microencapsulated curing agent is preferably a curing agent that is solid at 25°C and 1013 hPa. Therefore, even if the capsule is damaged during mixing of the components, the dissolution of the core component out of the capsule can be inhibited, maintaining preservation stability.

[0113] The average particle size of the core constituting the (B) microencapsulated curing agent is preferably greater than 0.3 μm and less than 12 μm. By making the average particle size of the core greater than 0.3 μm, the following effects are obtained: the aggregation of cores can be further prevented, the (B) microencapsulated curing agent is more easily formed, and the storage stability of the epoxy resin composition of this embodiment becomes sufficiently good in practical use. By making the average particle size of the core less than 12 μm, a homogeneous cured product can be obtained when the epoxy resin composition of this embodiment is cured. In addition, by making the average particle size of the core less than 12 μm, the formation of large-particle aggregates can be prevented when diluents, fillers, pigments, dyes, flow modifiers, thickeners, reinforcing agents, release agents, wetting agents, stabilizers, flame retardants, surfactants, organic solvents, conductive microparticles, crystalline alcohols, and other resins are mixed into the epoxy resin composition of this embodiment, and sufficient long-term reliability of the cured product can be obtained. Regarding the average nucleus size, as a lower limit, it is preferably greater than 0.3 μm, more preferably greater than 0.4 μm, and even more preferably greater than 0.5 μm. As an upper limit, it is preferably less than 12 μm, more preferably less than 10 μm, and even more preferably less than 9 μm.

[0114] The average particle size of the nucleus refers to the average particle size defined by the median particle size. More specifically, it refers to the Stokes particle size measured using a particle size analyzer (Horiba Manufacturing Co., Ltd., "HORIBA LA-920") and by laser diffraction / light scattering.

[0115] Methods for controlling the average particle size of the nucleus to the above-mentioned range are not limited to the following methods, and examples include: a method for precise control in the pulverization process of the bulk curing agent; a method for performing a coarse pulverization process and a micro pulverization process in the pulverization process of the bulk curing agent, and further using a precise grading device to grade and obtain a substance with a desired average particle size; and a method for spray drying a solution obtained by dissolving the bulk curing agent in a solvent.

[0116] As the equipment used in pulverization, various types of mills can be employed, such as ball mills, grinding mills, bead mills, and jet mills, with impact pulverization equipment being preferred. Examples of such impact pulverization equipment include rotary jet mills and reverse jet mills. Jet mills utilize a high-speed jet stream, such as air, to atomize solid materials by impacting each other. Methods for precise control during the pulverization process include controlling the temperature, humidity, and the amount of material pulverized per unit time. Methods for classifying materials to obtain a desired average particle size using a precise classifying device after the pulverization process include, for example, using sieves (e.g., standard sieves of 325 mesh, 250 mesh, etc.) or classifiers to obtain powder particles of a specified average particle size after pulverization; and classifying by airflow based on particle specific gravity. Examples of classifiers include wet classifiers and dry classifiers, with dry classifiers generally preferred. Examples of such classifiers include, but are not limited to, the "Elbow-Jet" manufactured by Nippon Steel Mining Co., Ltd., the "Fine Sharp Separator" manufactured by Hosokawa Micron Co., Ltd., the "Variable Impactor" manufactured by Sankyo Electric Co., Ltd., the "Spedic Classifier" manufactured by Saishin Enterprise Co., Ltd., the "DONASELEC" manufactured by DONALDSON Co., Ltd., the "YM Microcassette" manufactured by Yaskawa Corporation, the "TurboClassifier" manufactured by Nisshin Engineering Co., Ltd., and various other gas separators, micron separators, MICROPLEX, ACCU-CUT and other dry classification devices.

[0117] As a method for granulating the curing agent particles constituting the aforementioned core directly without pulverizing, one example is spray drying a solution obtained by dissolving a block-shaped curing agent in a solvent. Specifically, examples include methods such as uniformly dissolving the curing agent constituting the core in a suitable organic solvent, spraying it in the form of tiny droplets in a solution state, and then drying it with hot air. Conventional spray drying apparatuses can be used as drying devices in this process.

[0118] Another method for granulating the curing agent particles includes: uniformly dissolving the curing agent constituting the core in a suitable organic solvent, then, while vigorously stirring the solution to homogenize it, adding a poor solvent for the curing agent constituting the core, thereby causing the curing agent constituting the core to precipitate out in the form of tiny particles. Next, the precipitated particles are filtered and separated, and then dried at a low temperature below the melting point of the curing agent constituting the core to remove the solvent.

[0119] As a method for adjusting the average particle size of the curing agent constituting the core in a particulate state using methods other than grading, examples include methods such as adjusting the average particle size by mixing multiple particles with different average particle sizes. For example, in the case of large-particle-size curing agents that are difficult to pulverize and grade, it is also possible to produce a curing agent with an average particle size in the aforementioned range by adding and mixing small-particle-size curing agents that are different from them.

[0120] The curing agent obtained by this operation can be further graded as needed. As for mixers used for mixing such powders, examples include: container rotary mixers that rotate the container body containing the powder to be mixed; container stationary mixers that do not rotate the container body containing the powder but mix by means of mechanical stirring or airflow stirring; and composite mixers that rotate the container containing the powder and also use other external forces for mixing, etc.

[0121] The shape of the core constituting the (B) microcapsule curing agent is not limited to the following shapes, and can be any of the following: granular, powdery, irregular shape, irregular shape with rounded corners, etc.

[0122] The closer the shape of the core constituting the microencapsulated curing agent (B) is to a perfect sphere, the better. The closer the core is to a perfect sphere, the more uniformly the capsule membrane, which serves as the shell described later, will form, and the component (B) tends to exhibit low aggregation, excellent storage stability, and excellent solvent resistance. The degree of approximation to a perfect sphere is expressed by sphericity, where the sphericity of a perfect sphere is 1. The sphericity of the core of component (B) is preferably 0.93 or higher, more preferably 0.95 or higher, and even more preferably 0.98 or higher.

[0123] The sphericity of the core constituting the (B) microcapsule-type curing agent can be determined using flow-through particle image analysis. More specifically, this can be achieved by allowing the test sample to flow in a liquid and photographing the particles, determining the particle size based on the projected area of ​​the particles, and calculating the ratio of the perimeter of the particle projection image to the circumference of the particle size equivalent circle.

[0124] There are no particular limitations on the method for controlling the roundness of the core, but surface modification of the curing agent constituting the core is an effective method. Examples include mechanically rounding the particles or using hot air treatment.

[0125] <Shell>

[0126] (B) The microencapsulated curing agent preferably has a structure in which the surface of the core is covered by a shell containing synthetic resin and / or inorganic oxide. Among these, from the viewpoints of the stability of the film constituting the shell, the ease of damage during heating, and the uniformity of the cured epoxy resin composition of this embodiment, the shell constituting the (B) microencapsulated curing agent preferably contains synthetic resin.

[0127] The synthetic resin contained in the shell is not limited to the following substances, but may include, for example, epoxy resins, phenolic resins, polyester resins, polyethylene resins, nylon resins, polystyrene resins, and urethane resins. Among these, from the viewpoint of balancing the stability of the membrane constituting the shell with its destructive properties upon heating, epoxy resins, phenolic resins, and urethane resins are preferred.

[0128] The epoxy resin used in the shell is not limited to the following substances, and examples include epoxy resins having two or more epoxy groups, resins generated by reacting epoxy resins having two or more epoxy groups with compounds having two or more active hydrogen atoms, and reaction products of compounds having two or more epoxy groups with compounds having carbon-carbon double bonds and one active hydrogen atom. Among these, from the viewpoint of stability, resins generated by reacting compounds having two or more epoxy groups with compounds having two or more active hydrogen atoms are preferred, and reaction products of amine curing agents with epoxy resins having two or more epoxy groups are even more preferred.

[0129] As a phenolic resin, it is not limited to the following substances, but can include, for example, phenol-formaldehyde condensate, cresol-formaldehyde condensate, resorcinol-formaldehyde condensate, bisphenol A-formaldehyde condensate, and polyethylene polyamine modified from phenol-formaldehyde condensate.

[0130] As a polyester resin, it is not limited to the following substances, but can include, for example, ethylene glycol-terephthalic acid-polypropylene glycol condensate, ethylene glycol-butanediol-terephthalic acid condensate, terephthalic acid-ethylene glycol-polyethylene glycol condensate, etc.

[0131] As a polyethylene-based resin, it is not limited to the following substances, but can be listed as ethylene-propylene-vinyl alcohol copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-acrylic acid copolymer, etc.

[0132] As a nylon-based resin, it is not limited to the following substances, but can be listed as, for example, adipic acid-hexamethylenediamine condensate, sebacic acid-hexamethylenediamine condensate, p-phenylenediamine-terephthalic acid condensate, etc.

[0133] As a polystyrene-based resin, it is not limited to the following substances, but can be listed as styrene-butadiene copolymer, styrene-butadiene-acrylonitrile copolymer, acrylonitrile-styrene-divinylbenzene copolymer, styrene-propylene alcohol copolymer, etc.

[0134] As a urethane resin, it is not limited to the following substances, but may include isocyanate monomers such as butyl isocyanate, cyclohexyl isocyanate, octadecyl isocyanate, phenyl isocyanate, toluene diisocyanate, diphenylmethane diisocyanate, phenyl dimethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, bitoluidine diisocyanate, naphthalene diisocyanate, and triphenylmethane triisocyanate, or their condensates, or polymers thereof with monohydric alcohols or polyhydric alcohols. Among these, urethane resins are preferably addition polymers of monohydric alcohols or polyhydric alcohols with monoisocyanates or polyisocyanates.

[0135] As an inorganic oxide, it is not limited to the following substances, but can include boron compounds such as boron oxide and boron esters; silicon dioxide, calcium oxide, etc. Among these, boron oxide is preferred from the viewpoint of the stability of the membrane constituting the shell and its susceptibility to damage during heating.

[0136] Furthermore, from the viewpoint of balancing the storage stability and curability of the epoxy resin composition of this embodiment, the shell preferably contains one or more reaction products selected from the group consisting of isocyanate compounds, active hydrogen compounds, epoxy resin curing agents, epoxy resins, and amine compounds.

[0137] As isocyanate compounds, isocyanate compounds listed as examples of raw materials for the amine adducts contained in the above-mentioned core can be used.

[0138] As active hydrogen compounds, they are not limited to the following substances, but may include, for example, water, compounds having at least one primary amino group and / or secondary amino group, compounds having at least one hydroxyl group, etc. These active hydrogen compounds may be used alone or in combination of two or more.

[0139] As a compound having at least one primary amino group and / or secondary amino group, it is not limited to the following substances, but can be listed as, for example, aliphatic amines, alicyclic amines, aromatic amines, etc.

[0140] As an aliphatic amine, it is not limited to the following substances, but can include, for example, alkylamines such as methylamine, ethylamine, propylamine, butylamine, and dibutylamine; alkylene diamines such as ethylenediamine, propylenediamine, butylenediamine, and hexamethylenediamine; polyalkylene polyamines such as diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; and polyoxypropylene diamine and polyoxyethylene diamine, etc.

[0141] As an alicyclic amine, it is not limited to the following substances, but can be listed as cyclopropylamine, cyclobutylamine, cyclopentylamine, cyclohexylamine, isophorone diamine, etc.

[0142] As aromatic amines, they are not limited to the following substances, but can be listed as aniline, toluidine, benzylamine, naphthylamine, diaminodiphenylmethane, diaminodiphenyl sulfone, etc.

[0143] Examples of compounds having at least one hydroxyl group include alcohols and phenols.

[0144] As an alcohol compound, it is not limited to the following substances, but may include, for example, monohydric alcohols such as methanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecyl alcohol, lauryl alcohol, dodecyl alcohol, stearyl alcohol, eicosyl alcohol, allyl alcohol, crotonol, propargyl alcohol, cyclopentanol, cyclohexanol, benzyl alcohol, cinnamyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monobutyl ether, etc.; polyhydric alcohols such as ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-butanediol, 1,4-butanediol, hydrogenated bisphenol A, neopentyl glycol, glycerol, trimethylolpropane, pentaerythritol, etc.; and polyhydric alcohols such as compounds having two or more secondary hydroxyl groups in one molecule, obtained by reacting a compound having at least one epoxy group with a compound having at least one hydroxyl, carboxyl, primary amino, secondary amino, or thiol group.

[0145] These alcohol compounds can be any of the primary, secondary, or tertiary alcohols.

[0146] As phenolic compounds, they are not limited to the following substances, but can include monophenols such as phenol, cresol, xylenol, carvacrol, thymol, and naphthol; and polyphenols such as catechol, resorcinol, hydroquinone, bisphenol A, bisphenol F, pyrogallol, 2-(dimethylaminomethyl)phenol, and 2,4,6-tris(dimethylaminomethyl)phenol.

[0147] From the viewpoint of potential and solvent resistance, polyols and polyphenols are preferred as compounds having at least one hydroxyl group, and polyols are more preferred.

[0148] The reaction conditions for the reaction products contained in the shell of the microcapsule-type curing agent of the above-described composition (B) are not particularly limited, but are generally a temperature range of -10°C to 150°C and a reaction time of 10 minutes to 12 hours.

[0149] When using isocyanate compounds and active hydrogen compounds to prepare the reaction products contained in the shell, the mixing ratio of isocyanate groups in the isocyanate compound to active hydrogen in the active hydrogen compound (equivalent ratio) is preferably in the range of 1:0.1 to 1:1000.

[0150] The aforementioned reactions can be carried out in a specified dispersion medium as needed.

[0151] Examples of dispersion media include solvents, plasticizers, and resins.

[0152] As a solvent, it is not limited to the following substances, but may include hydrocarbons such as benzene, toluene, xylene, cyclohexane, mineral oil, and naphtha; ketones such as acetone, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK); esters such as ethyl acetate, n-butyl acetate, and propylene glycol monomethyl ethyl ether acetate; alcohols such as methanol, isopropanol, n-butanol, butyl cellosolve, and butyl carbitol; and water, etc.

[0153] As a plasticizer, it is not limited to the following substances, but can include, for example, phthalate ester plasticizers such as dibutyl phthalate and di(2-ethylhexyl) phthalate; aliphatic diester plasticizers such as di(2-ethylhexyl) adipate; phosphate triester plasticizers such as tricresyl phosphate; and glycol ester plasticizers such as polyethylene glycol ester.

[0154] As a type of resin, it is not limited to the following substances, but can include, for example, organosilicon resins, epoxy resins, phenolic resins, etc.

[0155] In the above-mentioned process, the reaction between the epoxy resin and the epoxy resin curing agent is typically carried out at a temperature range of -10°C to 150°C, preferably 0°C to 100°C, for a reaction time of 1 hour to 168 hours, and more preferably 2 hours to 72 hours. Furthermore, the preferred dispersion medium is a solvent or a plasticizer.

[0156] It should be noted that the reaction product contained in the shell as described above is typically 1% by mass or more, preferably 50% by mass or more, and can be 100% by mass.

[0157] In (B) microencapsulated curing agents, methods such as (1) to (3) below can be listed as methods for forming a shell covering the core surface.

[0158] (1): A method of dissolving / dispersing the capsule components and curing agent particles in a solvent as a dispersion medium, and then reducing the solubility of the capsule components in the dispersion medium to precipitate the capsules onto the surface of the epoxy resin curing agent particles.

[0159] (2): A method of dispersing the particles of the curing agent into a dispersion medium, adding the material that forms the above-mentioned capsules into the dispersion medium, and precipitating it onto the particles of the curing agent.

[0160] (3): A method of adding raw material components for forming capsules to a dispersion medium, using the surface of the curing agent particles as the reaction site, and generating a shell-forming material thereon.

[0161] Here, the methods (2) and (3) mentioned above can simultaneously carry out the reaction and coverage, and are therefore preferred.

[0162] It should be noted that, in the methods described in (1) to (3) above, solvents, plasticizers, resins, etc., can be used as dispersion media. In addition, substances listed as examples of solvents, plasticizers, and resins that can be used in the preparation of one or more reaction products selected from the group consisting of the above-mentioned isocyanate compounds, active hydrogen compounds, epoxy resin curing agents, epoxy resins, and amine compounds can be used as solvents, plasticizers, and resins.

[0163] After forming the shell using the methods described in (2) and (3) above, there is no particular limitation on the method for separating the (B) microencapsulated curing agent from the dispersion medium. However, it is preferable to separate / remove the unreacted material after shell formation together with the dispersion medium. As an example of this method, a method of removing the dispersion medium and unreacted shell-forming material by filtration can be cited.

[0164] Preferably, the microencapsulated curing agent is cleaned after the dispersion medium is removed. Cleaning with the microencapsulated curing agent removes unreacted shell-forming material adhering to the surface.

[0165] The cleaning method is not particularly limited. When cleaning based on filtration residues, a dispersion medium or a solvent that does not dissolve the microencapsulated curing agent can be used. By filtering, cleaning, and then drying the microencapsulated curing agent, it is possible to obtain it in powder form. The drying method is not particularly limited, but drying at a temperature below the melting or softening point of the curing agent is preferred; examples include vacuum drying. By making the microencapsulated curing agent into powder form, it is easy to mix it with epoxy resin (A). Furthermore, if epoxy resin is used as the dispersion medium, a masterbatch of the microencapsulated curing agent integrated with the epoxy resin can be obtained simultaneously with shell formation, making it suitable.

[0166] It should be noted that the shell formation reaction is usually carried out in the temperature range of -10℃ to 150℃, preferably 0℃ to 100℃, for a reaction time of 10 minutes to 72 hours, preferably 30 minutes to 24 hours.

[0167] Furthermore, from the viewpoint of balancing stability and reactivity, the shell constituting the (B) microencapsulated curing agent preferably has an absorption wavenumber of 1630–1680 cm⁻¹. -1 The infrared radiation contains urea-bonded groups with absorption wavenumbers of 1680–1725 cm⁻¹. -1 The biuret bonding group and absorption wavenumber of the infrared radiation are 1730–1755 cm⁻¹ -1 The urethane bonding group that emits infrared light.

[0168] The aforementioned urea-bonded groups, biuret-bonded groups, and urethane-bonded groups can be detected by measuring them using a Fourier transform infrared spectrophotometer (hereinafter sometimes referred to as "FT-IR"). In addition, the presence of urea-bonded groups, biuret-bonded groups, and urethane-bonded groups in the shell can be confirmed by microscopic FT-IR.

[0169] Specifically, for the epoxy resin composition of this embodiment, a modified aliphatic polyamine curing agent was added, and the mixture was cured at 40°C for 12 hours. Subsequently, it was further cured at 120°C for 24 hours to achieve partial and complete curing of the epoxy resin. Afterward, a 5–20 μm thick sample was prepared from the resulting cured material using a microscopic FT-IR microscope, and the depth direction of the shell was analyzed. By observing the area near the shell surface, the presence of urea-bonded groups, biuret-bonded groups, and urethane-bonded groups could be observed.

[0170] Furthermore, the thickness of the shell constituting the microencapsulated curing agent (B) is preferably 5 nm or more and 1000 nm or less, more preferably 10 nm or more and 100 nm or less. By setting the shell thickness to 5 nm or more, the storage stability of the epoxy resin composition of this embodiment can be further improved. Furthermore, by setting the shell thickness to 1000 nm or less, the curability can be further improved. It should be noted that the thickness mentioned here is the average layer thickness, which can be measured using a transmission electron microscope.

[0171] When (A) epoxy resin is set to 100 parts by mass, from the viewpoint of imparting sufficient reactivity, the content of (B) microencapsulated curing agent in the epoxy resin composition of this embodiment is preferably 1 part by mass or more, more preferably 5 parts by mass or more, even more preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, and even more preferably 30 parts by mass or more.

[0172] Furthermore, from the viewpoints of inhibiting the aggregation of (B) microencapsulated curing agents, imparting sufficient mechanical strength to the cured product, and imparting sufficient storage stability to the epoxy resin composition, it is preferable to use 100 parts by weight or less, more preferably 90 parts by weight or less, further preferably 80 parts by weight or less, even more preferably 75 parts by weight or less, and even more preferably 70 parts by weight or less.

[0173] (Component (C): Reactive diluent)

[0174] The epoxy resin composition of this embodiment includes component (C): reactive diluent (hereinafter sometimes referred to as (C) reactive diluent, component (C)).

[0175] Reactive diluents are compounds that have epoxy groups and acryloyl groups that can be incorporated into the cured structure. They are compounds that have the effect of reducing the viscosity of the epoxy resin composition by being contained in the epoxy resin composition of this embodiment.

[0176] As a (C) reactive diluent, it is not limited to the following substances, but can be listed as, for example, (meth)acrylate compounds and epoxy compounds that can achieve low viscosity without impairing reactivity.

[0177] In this specification, compounds other than those exemplified in epoxy resin (A) above, and whose viscosity at 25°C is 1 mPa·s or more and less than 3 Pa·s, are used as reactive diluents.

[0178] In the epoxy resin composition of this embodiment, from the viewpoint that it has good compatibility with the above-mentioned (A) epoxy resin and (B) microencapsulated curing agent and is incorporated into the cured structure after the reaction, the (C) reactive diluent is preferably an epoxy compound.

[0179] The (meth)acrylate compounds used as (C) reactive diluents are not limited to the following substances, but can be listed as, for example, compounds having (meth)acryloyl groups at both ends of a polyepoxyalkane, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, trimethylolpropane-type polyfunctional (meth)acrylate, pentaerythritol-type polyfunctional (meth)acrylate, dipentaerythritol-type polyfunctional (meth)acrylate, etc. Specifically, as difunctional (meth)acrylate compounds having two or more aromatic rings, examples include compounds having (meth)acrylate structures at both ends due to the addition of bisphenol A to a polyepoxyalkane, etc., and as monofunctional (meth)acrylate compounds having one aromatic ring, examples include phenyl (meth)acrylate, ethylene glycol monophenyl ether (meth)acrylate, etc.

[0180] The epoxy compounds used as reactive diluents (C) are not limited to the following substances, but can be listed as, for example, epoxy compounds without aromatic rings and epoxy compounds with aromatic rings.

[0181] Examples of monofunctional epoxy compounds that do not possess an aromatic ring include n-butyl glycidyl ether, tert-butyl glycidyl ether, allyl glycidyl ether, and 2-ethylhexyl glycidyl ether.

[0182] Examples of monofunctional epoxy compounds having one or more aromatic rings include styrene oxide, phenyl glycidyl ether, tolyl glycidyl ether, p-sec-butylphenyl glycidyl ether, tert-butylphenyl glycidyl ether, and the trade name SY-OPG manufactured by Sakamoto Pharmaceutical Co., Ltd.

[0183] Examples of difunctional epoxides that do not possess an aromatic ring include 1,4-cyclohexanediethanol diglycidyl ether, 1,3-cyclohexanediethanol diglycidyl ether, (3,4-epoxycyclohexyl)methyl-3,4-epoxycyclohexylcarboxylate, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, dicyclopentadiene diethanol diglycidyl ether, vinylcyclohexene dioxide, and the trade name YX-8000 manufactured by Mitsubishi Chemical Corporation and SR-8EGS manufactured by Sakamoto Pharmaceutical Co., Ltd.

[0184] Examples of difunctional epoxy compounds having one or more aromatic rings include hexahydrophthalic acid diglycidyl ether, resorcinol diglycidyl ether, tert-butylhydroquinone diglycidyl ether, diglycidyl ether of polyoxyalkylene bisphenol A, N,N-diglycidyl aniline, and N,N-diglycidyl o-toluidine.

[0185] Examples of trifunctional epoxy compounds include trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, and N,N-bis(2,3-epoxypropyl)-4-(2,3-epoxypropoxy)aniline.

[0186] In the epoxy resin composition of this embodiment, from the viewpoint of improving solvent resistance, the reactive diluent (C) preferably has an aromatic ring. Furthermore, from the viewpoint of further improving solvent resistance, the reactive diluent (C) is more preferably a monocyclic aromatic ring exhibiting monofunctionality, and particularly preferably a monofunctional compound having either an epoxy group or an acryloyl group as a functional group. Furthermore, from the viewpoint of exhibiting sufficient mechanical strength after being incorporated into the cured epoxy resin composition of this embodiment by component (C) after the reaction, the aforementioned monofunctional group is further preferably an epoxy group. Additionally, as described later, from the viewpoint of improving the penetration of component (B) into the capsule membrane and improving solvent resistance, the number of carbon atoms of each substituent in the aforementioned aromatic ring is particularly preferably 3 or less.

[0187] On the other hand, from the viewpoint of inhibiting the reaction between the (C) reactive diluent and the (A) epoxy resin and improving storage stability, the (C) reactive diluent is preferably free of nitrogen atoms.

[0188] The mechanism by which the reactive diluent (C) adopts the above-described structure to improve the solvent resistance of the epoxy resin composition of this embodiment is not intended to be limited thereto, but can be considered as follows.

[0189] When the reactive diluent (C) has aromatic rings, the aromatic rings of the reactive diluent incorporated into the shell of the aforementioned microencapsulated curing agent (B) exhibit a stacking effect to form a network, thereby improving the cohesive force of the shell. Therefore, a shell that is not easily swollen by solvents can be constructed, improving the solvent resistance of the epoxy resin composition of this embodiment.

[0190] Furthermore, by making the reactive diluent (C) a monocyclic and monofunctional aromatic ring compound, steric hindrance is reduced, thus facilitating penetration into the shell and enabling the formation of a denser, more extensive network of stacked aromatic rings. Here, by making the number of carbon atoms in each substituent of the aromatic ring 3 or less, steric hindrance is further reduced, penetration into the shell is improved, and solvent resistance is further enhanced.

[0191] From the viewpoint of imparting sufficient solvent resistance, the amount of reactive diluent (C) added relative to the epoxy resin composition of this embodiment is preferably 1% by mass or more, more preferably 3% by mass or more, further preferably 4% by mass or more, even more preferably 5% by mass or more, and even more preferably 6% by mass or more. Furthermore, from the viewpoint of suppressing excessive low viscosity, deterioration of storage stability, and reduction of the mechanical strength of the cured product, it is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 13% by mass or less, even more preferably 12% by mass or less, and even more preferably 11% by mass or less.

[0192] (Component (D): The compound shown in formula (1))

[0193] In the epoxy resin composition of this embodiment, as component (D), a compound represented by the following formula (1) is included (hereinafter sometimes referred to as component (D)).

[0194] By including component (D), the epoxy resin composition of this embodiment maintains high storage stability while improving low viscosity and low temperature curing properties, thereby ensuring a fully cured area even when the thermal conduction is uneven.

[0195]

[0196] In formula (1), X1 has two or more but no more than five consecutive carbon-carbon bonds. The carbon substituents in X1 and R1 to R5 are selected from the group consisting of hydrogen, alkyl, unsaturated aliphatic groups, aromatic groups, substituents containing heteroatoms, substituents containing halogen atoms, and halogen atoms. The carbon substituents in X1 and R1 to R5 may be the same or different from each other. The compound shown in formula (1) is optionally a fused-ring compound selected from any of R1 to R5 existing in the same ring.

[0197] The compounds represented by the aforementioned formula (1) are not limited to the following substances, but may include, for example, 3-phenoxy-1-propanol, 3-phenoxy-1,2-propanediol, 3-phenoxy-1,3-propanediol, cresol glycerol ether (3-(o-tolyloxy-1,2-propanediol), guaiacol ether (3-(2-methoxyphenoxy)propane-1,2-diol), bisphenol A (3-hydroxypropyl) glycidyl ether, bisphenol A (2,3-dihydroxypropyl) glycidyl ether, and the following compounds 1, 2, and 3.

[0198]

[0199] 3-(4-(2-(2-hydroxy-3-(4-(2-(4-(ethylene oxide-2-ylmethoxy)phenyl)propane-2-yl)phenoxy)propoxy)-3-(4-(2-(4-(ethylene oxide-2-ylmethoxy)phenyl)propane-2-yl)phenoxy)propoxy)phenyl)propane-2-yl)phenoxy)propane-1,2-diol

[0200]

[0201] 3-(4-(2-(4-(3-((1,3-bis(4-(2-(4-(ethylene-2-ylmethoxy)phenyl)propane-2-yl)phenoxy)

[0202] Propan-2-yl)oxy)-2-hydroxypropoxy)phenyl)prop-2-yl)phenoxy)propane-1,2-diol

[0203] 3-(4-(2-(4-(2-hydroxy-3-(4-(2-(4-(ethylene oxide-2-ylmethoxy)phenyl)propane-2-yl)phenoxy)propoxy)phenyl)propane-2-yl)phenoxy)propane-1,2-diol

[0204] The mechanism by which component (D) improves the low viscosity and low temperature curability of the epoxy resin composition of this embodiment and shows an effect on improving the cured area is not limited to this, but can be considered as follows.

[0205] The interactions between the aromatic ring stacking and hydrogen bonds of the epoxy resins (A) are replaced by the interactions between the epoxy resins (A) and component (D) through the aromatic groups and hydroxyl groups of component (D), thereby eliminating the interactions between the epoxy resins (A) and themselves. This allows for easier molecular movement in the epoxy resin composition as a whole, resulting in lower viscosity. Furthermore, during curing, coordination bonds are formed between the hydroxyl groups of component (D) and the curing agent component in the microencapsulated curing agent (B), thereby improving the compatibility between the curing agent component and the epoxy resin (A). This enhances the diffusivity of the curing agent in the epoxy resin composition, enabling a rapid reaction at lower temperatures. Furthermore, since the epoxy resin composition of this embodiment contains the reactive diluent (C), the epoxy resin composition achieves further lower viscosity, and the aforementioned diffusivity is dramatically improved. Therefore, based on the above mechanism, it can be concluded that when the compatibility of components (D), (A) epoxy resin, and (C) reactive diluent is good, a particularly superior improvement in reactivity is exhibited.

[0206] In addition, in this mechanism, component (D) plays a catalytic role in the reaction between the curing agent and the epoxy group until it is incorporated into the polymer.

[0207] The improvement in the cured region also contributes to the improved compatibility and diffusion of the curing agent coordinated with component (D) and epoxy resin (A) and reactive diluent (C). The effects of interaction, coordination, and compatibility are significantly influenced by the molecular structure. Therefore, in the epoxy resin composition of this embodiment, component (D) comprises the compound shown in formula (1) above.

[0208] From the viewpoint of suppressing steric hindrance when forming coordination bonds with curing agent components in (B) microencapsulated curing agent and exhibiting good curing properties, component (D) is preferably the compound shown in the following formula (2).

[0209]

[0210] In formula (2), X2 has two or more but no more than four consecutive carbon-carbon bonds. The carbon substituents in X2 and R1 to R5 are selected from the group consisting of hydrogen, alkyl, unsaturated aliphatic groups, aromatic groups, substituents containing heteroatoms, substituents containing halogen atoms, and halogen atoms. The carbon substituents in X2 and R1 to R5 may be the same or different from each other. The compound shown in formula (2) is optionally a fused-ring compound selected from any of R1 to R5 existing in the same ring.

[0211] From the viewpoint of good diffusion in epoxy resin after forming coordination bonds with the curing agent component in (B) microencapsulated curing agent, component (D) is more preferably a compound with two consecutive carbon-carbon bonds as shown in the following formula (3).

[0212]

[0213] In formula (3), R1 to R9 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatom, substituent containing halogen atom and halogen atom.

[0214] R1 to R9 may be chosen to be the same or different from each other. And the compound shown in formula (3) may be a fused ring compound selected from any of R1 to R5 that exists in the same ring.

[0215] From the viewpoint of improving solvent resistance, stability during film fabrication, and storage stability of the film, component (D) is further preferably a compound shown in formula (4) below, in which R9 in the aforementioned formula (3) is a hydroxyl group.

[0216]

[0217] In formula (4), R1 to R8 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatom, substituent containing halogen atom and halogen atom.

[0218] R1 to R8 may be chosen to be the same or different from each other. And the compound shown in formula (4) may be a fused ring compound selected from any of R1 to R5 that exists in the same ring.

[0219] Furthermore, from the viewpoint of reducing steric hindrance in order to improve coordination in the curing agent component, R6, R7, and R8 of the compounds shown in the aforementioned formulas (3) and (4) as component (D) are preferably hydrogen atoms.

[0220] From the viewpoint that component (D) can function effectively, R1 to R5 in the compounds represented by the aforementioned formulas (1) to (4) of component D are preferably free of epoxy groups and the structure of the following formula (5) (terminal diol structure).

[0221]

[0222] The compounds shown in formulas (1) to (4) above, which are components (D), can function for a long time by ensuring that R1 to R5 do not have epoxy groups, so that they are not incorporated into the curing reaction system.

[0223] Furthermore, R1 to R5 have the structure of the aforementioned formula (5), and the compounds of the aforementioned formulas (1) to (4) have two or more functional groups that can coordinate with the curing agent in a positional relationship with minimal steric hindrance. As a result, coordinate bonds are formed between multiple molecules, thereby reducing molecular mobility. Therefore, R1 to R5 in the compounds of the aforementioned formulas (1) to (4) preferably do not contain the structure of the aforementioned formula (5) (terminal diol structure).

[0224] As an indicator of compatibility, the sp value (δ) is used. When the difference in sp values ​​between compounds is small, they show good compatibility.

[0225] Since component (D) has excellent compatibility with the aforementioned epoxy resin (A) and reactive diluent (C), and the coordination compound formed by component (D) in coordination with the curing agent has excellent compatibility with the aforementioned epoxy resin (A) and reactive diluent (C), the epoxy resin composition of this embodiment further exhibits the effects of low viscosity, improved low-temperature curing properties, and improved curing area. Therefore, the sp value of component (D) is preferably close to the sp value of epoxy resin (A) and reactive diluent (C).

[0226] The sp values ​​of each compound at 25°C are calculated using the values ​​recorded in ROBERT F. FEDORS's POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol. 14, No. 2, and Fedors' calculation method (mathematical formula (i)).

[0227] In the following formula, δ represents the value of sp.

[0228] δ=(ΣΔe / ΣΔv) 1 / 2 …Mathematical expression (i)

[0229] Δe represents the cohesive energy of each substituent, and Δv represents the molar volume of a molecule.

[0230] [Ingredients (A)]

[0231] Bisphenol A type epoxy resin (n=0)...δ=10.9 (cal / cm³) 3 ) 1 / 2

[0232] Bisphenol F type epoxy resin (n=0 volume)...δ=12.1 (cal / cm) 3 ) 1 / 2

[0233] 1,6-Bis(2,3-epoxypropoxy)naphthalene…δ=13.1(cal / cm) 3 ) 1 / 2

[0234] [Ingredient (C)]

[0235] Phenylated glycidyl ether…δ=10.6(cal / cm) 3 ) 1 / 2

[0236] o-Tolyl glycidyl ether…δ=9.7(cal / cm) 3 ) 1 / 2

[0237] 1,6-Hexanediol diglycidyl ether…δ=9.8 (cal / cm) 3 ) 1 / 2

[0238] [Component (D)]

[0239] 3-Phenoxy-1-propanol…δ=12.0 (cal / cm) 3 ) 1 / 2

[0240] 3-Phenoxy-1,2-Propanediol…δ=14.3 (cal / cm) 3 ) 1 / 2

[0241] Cresol glycerol ether…δ=13.0 (cal / cm) 3 ) 1 / 2

[0242] Guaifenesin…δ=13.0 (cal / cm) 3 ) 1 / 2

[0243] Bisphenol A (3-hydroxypropyl) glycidyl ether…δ=11.6 (cal / cm) 3 ) 1 / 2

[0244] Bisphenol A (2,3-dihydroxypropyl) glycidyl ether…δ=12.9 (cal / cm) 3 ) 1 / 2

[0245] Compound 1 …δ=12.0 (cal / cm) 3 ) 1 / 2

[0246] Compound 2 …δ=12.0 (cal / cm) 3 ) 1 / 2

[0247] Compound 3 …δ=12.6 (cal / cm) 3 ) 1 / 2

[0248] From the viewpoint of further enhancing the effects of low viscosity, improved low-temperature curing properties, and improved cured area of ​​the epoxy resin composition of this embodiment, (A) the epoxy resin and / or (C) the reactive diluent contain an sp value of 9 to 14 (cal / cm). 3 ) 1 / 2 When using epoxy resin, the sp value of component (D) is preferably 7 (cal / cm³) as a lower limit. 3 ) 1 / 2 The above is preferred, with 8 (cal / cm³) being more ideal. 3 ) 1 / 2 The above is further preferred to be 9 (cal / cm). 3 ) 1 / 2 The above is further preferred to be 10 (cal / cm). 3 ) 1 / 2 The above is further optimized to 11 (cal / cm). 3 ) 1 / 2 The above is the upper limit. Preferably, it is less than 20 (cal / cm³). 3 ) 1 / 2 More preferably 18 (cal / cm) 3 ) 1 / 2 The following is a further preferred value: 16 (cal / cm³) 3 ) 1 / 2 the following.

[0249] From the viewpoint of fully utilizing the effects of low viscosity and improved catalytic reactivity of the epoxy resin composition of this embodiment, the amount of component (D) added relative to the total epoxy resin composition is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, further preferably 0.01% by mass or more, and even more preferably 0.012% by mass or more. Furthermore, from the viewpoint of suppressing the deterioration of storage stability due to excessive addition, it is preferably 5% by mass or less, more preferably 3% by mass or less, further preferably 2.5% by mass or less, and even more preferably 2% by mass or less.

[0250] Component (D) can be added when mixed with other components, or it can be generated in the system after mixing. In addition, it can also be generated in the system when manufacturing (A) epoxy resin, (B) microencapsulated curing agent and (C) reactive diluent.

[0251] (Other additives)

[0252] In the epoxy resin composition of this embodiment, in addition to the above-mentioned components, as curing agents and additives other than (B) microencapsulated curing agents, organic fillers, inorganic fillers, pigments, dyes, flow modifiers, thickeners, release agents, wetting agents, flame retardants, surfactants, resins, etc., may be further included as organic fillers, inorganic fillers, pigments, dyes, flow modifiers, thickeners, release agents, wetting agents, flame retardants, surfactants, resins, etc.

[0253] Other than (B) microencapsulated curing agents, curing agents and active ester compounds listed in the core components of the aforementioned microencapsulated curing agents can be included as curing agents.

[0254] Organic fillers function as shock absorbers that can mitigate stress caused by impact.

[0255] The epoxy resin composition of this embodiment can further improve adhesion to various connecting components by containing organic fillers. Furthermore, it tends to suppress the occurrence and aggravation of filler cracks.

[0256] Organic fillers are not limited to the following substances, but may include, for example, acrylic resins, silicone resins, butadiene rubber, polyesters, polyurethanes, polyvinyl butyral, polyarylates, polymethyl methacrylate, acrylic rubbers, polystyrene, NBR, SBR, silicone-modified resins, and organic microparticles of copolymers containing them as components.

[0257] From the perspective of improving adhesion, examples of organic microparticles include (meth)acrylate alkyl ester-butadiene-styrene copolymers, (meth)acrylate alkyl ester-organosilicon copolymers, organosilicon-(meth)acrylate copolymers, organosilicon and (meth)acrylate complexes, (meth)acrylate alkyl ester-butadiene-styrene and organosilicon complexes, and (meth)acrylate alkyl ester and organosilicon complexes.

[0258] Alternatively, organic particles with a core-shell structure and different compositions of the core and shell layers can also be used as the aforementioned organic particles. Examples of core-shell organic particles include particles with an organosilicon-acrylic rubber core grafted with acrylic resin, and particles obtained by grafting acrylic resin onto an acrylic copolymer.

[0259] These organic fillers can be used alone or in combination of two or more.

[0260] Inorganic fillers can adjust the coefficient of thermal expansion of the epoxy resin composition of this embodiment. Therefore, by containing inorganic fillers, there is a tendency to improve the heat resistance and moisture resistance when the epoxy resin composition of this embodiment is used as a bottom filler material.

[0261] As inorganic fillers, they are not limited to the following substances, but may include silicates such as talc, calcined clay, uncalcined clay, mica, and glass; oxides such as titanium dioxide, aluminum oxide, fused silica (e.g., fused spherical silica and fused broken silica), synthetic silica, and crystalline silica; carbonates such as calcium carbonate, magnesium carbonate, and hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide; sulfates such as barium sulfate and calcium sulfate; sulfites such as calcium sulfite; borates such as zinc borate, barium metaborate, aluminum borate, calcium borate, and sodium borate; and nitrides such as aluminum nitride, boron nitride, and silicon nitride.

[0262] Among these, fused silica, crystalline silica, and synthetic silica powder are preferred from the viewpoint of improving heat resistance, moisture resistance, and strength; furthermore, any one of alumina and boron nitride is preferred. By using them, the coefficient of thermal linear expansion can be suppressed, and therefore, improvements in thermal cycling tests are expected.

[0263] The shape of inorganic fillers is not particularly limited and can be any shape, such as irregular, spherical, or scale-like.

[0264] These inorganic fillers can be used alone or in combination of two or more.

[0265] As a pigment, it is not limited to the following substances, but can include, for example, kaolin, aluminum oxide trihydrate, aluminum hydroxide, chalk powder, gypsum, calcium carbonate, antimony trioxide, Pantone, silicon dioxide, aerosols, zinc barium white, barite, titanium dioxide, etc.

[0266] As a dye, it is not limited to the following substances, but can include, for example, dyes derived from plants such as madder and indigo; natural dyes derived from minerals such as loess and red clay; synthetic dyes such as alizarin and indigo; and fluorescent dyes.

[0267] As a flow regulator, it is not limited to the following substances, but can be listed as organosilane compounds such as silane coupling agents; organotitanium compounds such as tetraisopropoxide titanium and diisopropoxybis(acetylacetone)titanium; organozirconium compounds such as tetra-n-butoxide zirconium and tetraacetylacetone zirconium, etc.

[0268] As a thickener, it is not limited to the following substances, but can include animal-based thickeners such as gelatin; plant-based thickeners such as polysaccharides and cellulose; and chemically synthesized thickeners such as polyacrylic acid thickeners, modified polyacrylic acid thickeners, polyether thickeners, urethane-modified polyether thickeners, and carboxymethyl cellulose.

[0269] As a release agent, it is not limited to the following substances, but can include, for example, fluorinated release agents, silicone release agents, and acrylic release agents formed by copolymers of glycidyl methacrylate and linear alkyl (meth)acrylates with 16 to 22 carbon atoms.

[0270] As a wetting agent, it is not limited to the following substances, but can include, for example, unsaturated polyester copolymers with acidic groups such as acrylic polyphosphate esters.

[0271] As a flame retardant, it is not limited to the following substances, but can include, for example, metal hydroxides such as aluminum hydroxide and magnesium hydroxide; halogen-based flame retardants such as chlorine compounds and bromine compounds; phosphorus-based flame retardants such as condensed phosphate esters; antimony-based flame retardants such as antimony trioxide and antimony pentoxide; and inorganic oxides such as silica fillers.

[0272] As surfactants, they are not limited to the following substances, but can include anionic surfactants such as alkylbenzene sulfonates and alkyl polyoxyethylene sulfates; cationic surfactants such as alkyl dimethyl ammonium salts; amphoteric surfactants such as alkyl dimethyl amine oxides and alkyl carboxylic betaine; and nonionic surfactants such as straight-chain alcohols and fatty acid esters with more than 25 carbon atoms.

[0273] As a type of resin, it is not limited to the following substances, but may include, for example, organosilicon resins, phenolic resins, phenoxy resins, polyvinyl butyral resins, polyvinyl acetal resins, polyacrylic acid resins, polyimide resins; and elastomers having functional groups such as carboxyl, hydroxyl, vinyl and amino groups.

[0274] [Method for manufacturing epoxy resin composition]

[0275] The method for manufacturing the epoxy resin composition according to this embodiment includes a step of mixing the above-mentioned (A) epoxy resin, (B) microencapsulated curing agent, (C) reactive diluent and component (D) compound to obtain the epoxy resin composition.

[0276] The method for manufacturing the epoxy resin composition according to this embodiment includes: first mixing (A) epoxy resin, (C) reactive diluent, and a compound of component (D), and then adding (B) microencapsulated curing agent; mixing (B) microencapsulated curing agent, (C) reactive diluent, and a compound of component (D), and then adding (A) epoxy resin; furthermore, for a masterbatch in which (A) epoxy resin and (B) microencapsulated curing agent are integrally formed, adding (A) epoxy resin, (B) microencapsulated curing agent, (C) reactive diluent, and a compound of component (D), etc. The mixing method is not particularly limited, and can be appropriately selected from methods such as using a planetary mixer or a three-roll mill. Additionally, (B) microencapsulated curing agent can be manufactured using any of the above methods.

[0277] [Method for manufacturing curable resin composition]

[0278] The epoxy resin composition of this embodiment can also be used as a masterbatch-type epoxy resin curing agent to manufacture a curable resin composition. That is, by adding epoxy resin and other curing agents to the epoxy resin composition of this embodiment, a curable resin composition can be manufactured. In this case, the curable resin composition is also included in the embodiments of the present invention.

[0279] The curable resin composition can be obtained by thoroughly mixing the epoxy resin composition of this embodiment, (A) epoxy resin, curing agent listed as the core component of (B) microencapsulated curing agent, and other additives until homogeneous using an open mill such as a three-roll mill, a disperser, a planetary mixer, a kneader, an extruder, etc.

[0280] The epoxy resin composition, curable resin composition, and epoxy resin composition mixture for films described later in this embodiment can also be subjected to heat treatment at a temperature of 30°C to 80°C for 1 to 168 hours. The heating method is not particularly limited; examples include heating using an oven, incubator, water bath, or oil bath. Furthermore, the temperature process is not particularly limited; for example, the temperature can be increased in stages or increased all at once.

[0281] Heating can bring together the reactions of the remaining functional groups that occurred at low temperatures.

[0282] [Specific methods for the epoxy resin composition and the curable resin composition]

[0283] The epoxy resin composition and the curable resin composition using the present embodiment are not limited to the following compositions, and are suitable for sealing materials, insulating materials, adhesives, conductive materials, matrix resins of fiber-reinforced plastics, impregnation and fixing materials for motor coils, etc. of electrical and electronic components such as bottom filler materials and relay sealing materials.

[0284] For example, for underfill materials, the desired properties include low viscosity for rapid impregnation between the semiconductor chip and the substrate, stability relative to heating during impregnation, and excellent curability at temperatures above 100°C. The epoxy resin composition of this embodiment possesses all of these characteristics. Furthermore, for the large-area application of semiconductor chips, the epoxy resin composition of this embodiment is suitable from the viewpoint that it can ensure a sufficiently cured area even in cases of uneven thermal conductivity.

[0285] Furthermore, the matrix resin of fiber-reinforced plastics and the impregnation fixing material of motor coils require permeability into the gaps of microfibers or coils, stability during impregnation, and curing properties. The epoxy resin composition of this embodiment possesses all of these characteristics and is therefore suitable.

[0286] The curable resin composition obtained using the epoxy resin composition of this embodiment also has the same properties, therefore, the above method is suitable.

[0287] (A film containing the epoxy resin composition of this embodiment)

[0288] The film of this embodiment has a resin composition layer comprising the epoxy resin composition of this embodiment.

[0289] In this case, the epoxy resin composition can also function as an epoxy resin curing agent or curing accelerator. The epoxy resin composition of this embodiment has excellent low viscosity, solvent resistance, storage stability, and curability, making it suitable for films.

[0290] The film of this embodiment has, for example, a specified support and a resin composition layer formed on the support by an epoxy resin composition blend liquid described later. If necessary, a protective layer may also be provided on the surface of the aforementioned resin composition layer opposite to the support.

[0291] <Preparation method of epoxy resin composition blend for thin films>

[0292] As a method for preparing an epoxy resin composition mixture for forming a resin composition layer for a thin film, examples include mixing the epoxy resin composition of this embodiment, (A) epoxy resin, a curing agent listed as the core component of (B) microencapsulated curing agent, other additives, component (E): a polymer for forming a thin film, etc., further adding component (F): an organic solvent, and mixing using a planetary mixer or the like.

[0293] As the aforementioned (E) film-forming polymer, any polymer having the following effects can be used: suppressing cracks, depressions, and excessive flow during film formation by drying the organic solvent after coating the epoxy resin composition mixture, and maintaining the film shape. This component (E) is not limited to the following substances, but may include, for example, phenoxy resins, polyvinyl butyral resins, polyvinyl acetal resins, polyacrylic resins, polyimide resins; and elastomers having functional groups such as carboxyl, hydroxyl, vinyl, and amino groups.

[0294] (E) Polymers used for film forming are sometimes also referred to as binder polymers.

[0295] As for (F) organic solvents, there are no particular limitations, and known solvents may be used. Examples of solvents not limited to include: hydrocarbons such as toluene, xylene, cyclohexane, mineral oil, and solvent naphtha; ketones such as acetone, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK); esters such as ethyl acetate, n-butyl acetate, and propylene glycol monomethyl ethyl ether acetate; alcohols such as methanol, isopropanol, n-butanol, butyl cellosolve, and butyl carbitol; and amide solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone.

[0296] <Support Body>

[0297] The preferred support is a material that can withstand the temperature required for drying organic solvents. Such a support is not limited to the following materials, but includes, for example, polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film, etc.

[0298] These films can also be used as needed, and films that have been stretched can also be used.

[0299] <Protective Layer>

[0300] As a protective layer, a material that can adequately maintain the smoothness of the surface of the resin composition layer is preferred. Such a protective layer is not limited to the following, and polyethylene film, polypropylene film, easily peelable polyethylene terephthalate film, oriented polypropylene film, etc., are preferred.

[0301] <Thin Film Manufacturing Methods>

[0302] The film of this embodiment can be manufactured by sequentially stacking a support and a resin composition layer, and a protective layer as needed.

[0303] Known methods can be used as the lamination method for the support, resin composition layer and protective layer.

[0304] For example, to prepare a mixture comprising the epoxy resin composition of this embodiment and (F) organic solvent, firstly, the mixture is applied to a support using a known method such as an applicator or bar coater and dried to form a resin composition layer on the support. The drying method is not particularly limited, and examples include an oven and hot air blowing. Furthermore, the drying temperature and time are not particularly limited. From the viewpoint of sufficiently removing the solvent and suppressing deformation of the support due to overheating and residual reaction of the resin composition layer during drying, drying is preferably performed within a temperature range of 50°C to 160°C and a drying time of 1 minute to 30 minutes, more preferably within a temperature range of 80°C to 150°C and a drying time of 3 minutes to 25 minutes. It should be noted that the drying temperature can be a constant temperature or a temperature gradient can be applied. Next, if necessary, a protective layer is deposited on the formed resin composition layer to produce a thin film.

[0305] <Specific methods for thin films>

[0306] The film in this embodiment is not limited to the following films, and can be used as, for example, interlayer insulating film, thin-film solder resist, sealing sheet, conductive film, anisotropic conductive film, thermally conductive film, etc.

[0307] The epoxy resin composition of this embodiment exhibits excellent solvent resistance and storage stability, thus extending the coating time of the epoxy resin composition mixture containing it for film preparation and extending the shelf life of the resulting film. In particular, films that are typically frozen can be stored at refrigeration to near room temperature.

[0308] In addition, the epoxy resin composition of this embodiment has low viscosity, so it is easy to control the viscosity of the liquid containing it, and it also has excellent coating properties on the support.

[0309] Furthermore, the resin composition layer containing the epoxy resin composition of this embodiment is sufficiently reduced in viscosity by heating during film bonding, and exhibits excellent stability during film manufacturing and storage. Therefore, the reaction of the epoxy compound after film manufacturing is suppressed, and low viscosity can be maintained for a long time. Due to these characteristics, the film of this embodiment exhibits excellent surface conformability and can be bonded to the substrate without gaps.

[0310] Furthermore, the epoxy resin composition of this embodiment has excellent curability at around 100°C, therefore, the film of this embodiment also has excellent curability.

[0311] The above-mentioned characteristics are required by interlayer insulating films, thin-film solder resists, sealing sheets, conductive films, anisotropic conductive films, and thermally conductive films. Therefore, the film of this embodiment is suitable for these methods.

[0312] [Cured material]

[0313] The cured product of this embodiment is the cured product of the epoxy resin composition of this embodiment and the film of this embodiment.

[0314] The cured product of this embodiment can be manufactured by subjecting the epoxy resin composition and film of this embodiment to heat treatment.

[0315] Heat treatment can be performed, for example, by heating in a furnace such as an oven, or by hot pressing. Furthermore, there are no particular limitations on the heating conditions; they can be appropriately selected based on the composition of the epoxy resin composition and the heat treatment apparatus.

[0316] The cured product of this embodiment has excellent mechanical strength.

[0317] Example

[0318] Hereinafter, specific embodiments and comparative examples are given for the purpose of describing this embodiment, but this embodiment is not limited to the following embodiments and comparative examples.

[0319] It should be noted that the "parts" and "%" below are quality standards unless otherwise specified.

[0320] [Manufacturing method of microencapsulated curing agent]

[0321] (Manufacturing Example 1)

[0322] 50 parts by weight of bisphenol A type epoxy resin A-1 (epoxy equivalent of 186 g / eq, total chlorine content of 600 ppm, hydrolyzable chlorine content of 50 ppm, hereinafter referred to as "epoxy resin A-1"), 50 parts by weight of bisphenol F type epoxy resin A-2 (epoxy equivalent of 172 g / eq, total chlorine content of 500 ppm, hydrolyzable chlorine content of 100 ppm, hereinafter referred to as "epoxy resin A-2"), 100 parts by weight of curing agent core component b-1 (manufactured by Asahi Kasei Corporation, a solid amine adduct with a sphericity of 0.93, hereinafter referred to as "core b-1"), and 10 parts by weight of encapsulation agent c-1 (manufactured by Nippon Polyurethane Co., Ltd.: MR-400) were added, dispersed and mixed, and then reacted at 55°C for 5 hours to obtain microencapsulated curing agent B-1 dispersed in epoxy resin.

[0323] (Manufacturing Example 2)

[0324] Add 50 parts by weight of "epoxy resin A-1", 50 parts by weight of "epoxy resin A-2", 100 parts by weight of "nucleus b-1" and 10 parts by weight of encapsulation agent c-2 (manufactured by Tosoh Corporation: T-80), disperse and mix them, and then react them at 55°C for 5 hours to obtain microencapsulated curing agent B-2 dispersed in epoxy resin.

[0325] (Manufacturing Example 3)

[0326] 50 parts by weight of "epoxy resin A-1", 50 parts by weight of "epoxy resin A-2", 100 parts by weight of "core component b-1", 7 parts by weight of encapsulation agent c-3 (manufactured by Tosoh Corporation: CORONATE 1391) and 3 parts by weight of encapsulation agent c-4 (manufactured by Asahi Kasei Corporation: DURANATE TUL-100) were added, dispersed and mixed, and then reacted at 55°C for 5 hours to obtain microcapsule-type curing agent B-3 dispersed in epoxy resin.

[0327] [Preparation of epoxy resin composition]

[0328] The epoxy resin composition was obtained by measuring (A) epoxy resin, (B) microencapsulated curing agent, (C) reactive diluent, and component (D): the compound shown in formula (1) in the proportions shown in Tables 1 to 3 below, mixing them, and filtering them at 55°C for 48 hours.

[0329] The number of epoxy resin components (A) listed in Tables 1 to 3 below refers to the total amount of epoxy resin in the epoxy resin composition, including the epoxy resin simultaneously mixed with the "microencapsulated curing agent dispersed in the epoxy resin" prepared in Manufacturing Examples 1, 2, and 3. Therefore, the number of components (B) of the "microencapsulated curing agent" listed in Tables 1 to 3 below refers to the number of components of the microencapsulated curing agent itself, which consists of a core and a shell.

[0330] [Methods for determining and evaluating characteristics]

[0331] (Determination of the initial viscosity of the epoxy resin composition)

[0332] The viscosity (initial viscosity) of the epoxy resin composition was measured at room temperature (25°C) using an E-type viscometer (TVE-35H, manufactured by Toki Sangyo Co., Ltd.).

[0333] From the viewpoint of sufficient gap penetration and the manufacturing adaptability of the resin composition layer constituting the film, the following evaluation is made: the initial viscosity is preferably 4500 mPa·s or less, more preferably 3500 mPa·s or less, and even more preferably 3000 mPa·s or less.

[0334] (Storage stability: Viscosity ratio for storage stability)

[0335] The initial viscosity of the epoxy resin composition immediately after preparation and the viscosity of the epoxy resin composition after being placed at 40°C for 7 days were measured at room temperature (25°C) using an E-type viscometer, and the storage stability viscosity ratio was calculated using the following mathematical formula (1).

[0336] Storage stability viscosity ratio = Viscosity after 7 days at 40℃ / Initial viscosity... Mathematical formula (1)

[0337] The following evaluation is made: the viscosity ratio for storage stability is preferably 1.2 or less, more preferably 1.1 or less, and even more preferably 1.0.

[0338] (The temperature at which the dynamic viscosity reaches the specified viscosity (curing at around 100°C), as determined by a rheometer)

[0339] Using a rheometer (HAAKE MARS, Thermo Scientific), the epoxy resin composition was heated from 25°C to 200°C at a heating rate of 5°C / min and in oscillating mode (f = 1 Hz), and the dynamic viscosity η'-temperature curve was obtained.

[0340] Based on the obtained dynamic viscosity-temperature curve, it was confirmed that the dynamic viscosity reached 10. 5 Temperature in mPa·s: T (°C).

[0341] Based on the temperature: T (°C), the following evaluation is conducted.

[0342] T≤95℃…◎

[0343] 95℃ <T≤105℃…〇

[0344] 105℃ <T≤110℃…△

[0345] 110℃ <T…×

[0346] (Cure area)

[0347] The epoxy resin composition is fully poured into a Teflon (registered trademark) mold with a length of 550mm × width of 350mm × thickness of 2mm until the opening is reached, and then heated in a heating furnace at a set temperature of 100°C for 25 minutes.

[0348] The volume of the cured body removed from the Teflon (registered trademark) mold after heating is set as Vc, and the inflow volume of the epoxy resin composition is set as V0. The cured area is calculated using the following mathematical formula (2).

[0349] Cured area (%) = 100 × Vc / V0… Mathematical formula (2)

[0350] The following criteria are used to evaluate the area based on the percentage of the cured region.

[0351] ◎Cure area: 100%

[0352] 〇 Cured area: 80% or more but less than 100%

[0353] △Cure area: 50% or more but less than 80%

[0354] ×Cure area: less than 50%

[0355] The larger the curing area when the epoxy resin composition is cured, the more fully cured the area can be ensured even if the heat conduction in the curing area is insufficient. From this point of view, it is rated as excellent.

[0356] That is, starting from the side with a good rating, the values ​​are listed in the table in the order of ◎, 〇, △, ×.

[0357] (Soluble resistance stability)

[0358] Samples were prepared by mixing 20 parts by mass of MEK (methyl ethyl ketone) as a solvent into 80 parts by mass of the epoxy resin compositions of Examples 1-19 and Comparative Example 2.

[0359] The obtained sample was heated at 50°C, and the time (h) until the fluidity disappeared was measured.

[0360] The following evaluation is made: the time until the fluidity disappears is preferably 0.5 hours (h) or more, more preferably 1 hour (h) or more, and even more preferably 2 hours (h) or more.

[0361] (Stability when using epoxy resin compositions to make films)

[0362] A solution was prepared by mixing and dissolving 50 parts by weight of phenoxy resin (manufactured by InChem, trade name "PKHB"), 50 parts by weight of bisphenol A type liquid epoxy resin (manufactured by Mitsubishi Chemical, trade name "jER828"), and 100 parts by weight of MEK. Then, 20 parts by weight of any epoxy resin composition from Examples 1-19 and Comparative Example 2 were mixed into 100 parts by weight of this solution to prepare a mixing liquid for epoxy resin compositions for films.

[0363] The mixed solution was coated onto a polyethylene terephthalate film (50 μm thick) serving as a support, with a dried film thickness of 40 μm. After drying in an oven preheated to 120°C for 5 minutes, the side opposite the support was protected with an easily peelable polyethylene terephthalate film to obtain the film. These were used as films in Examples 20–38 and Comparative Example 4, respectively.

[0364] The FT-IR spectrum of the obtained thin film was measured using a Fourier transform infrared spectrophotometer (FT / IR-6600, manufactured by Nippon Spectrophotometer Co., Ltd.).

[0365] 2920cm derived from methylene-derived epoxy and phenoxy resins whose strength does not change due to heat drying -1 Using the nearby absorbance P1 as a baseline, it was compared with the 915 cm⁻¹ of the epoxy group source. -1 The strength ratio of the nearby absorber P2, P2 / P1, is the same as the strength ratio P20 / P10 (P10 is 2920 cm⁻¹) when the film is made according to the same operation as when the microencapsulated curing agent component in the epoxy resin composition as a curing agent component is removed. -1 Nearby absorption, P20 is the 915cm group of epoxy groups -1 By comparing with the absorption in the vicinity, the epoxy consumption rate is calculated using the following mathematical formula (3).

[0366] Epoxy consumption rate = 100 - [(P2 / P1) / (P20 / P10)] × 100... Equation (3)

[0367] The following criteria are used to evaluate the epoxy consumption rate.

[0368] 0% ≤ Epoxy Consumption Rate < 10%...◎

[0369] 10% ≤ epoxy consumption rate < 15%...

[0370] 15% ≤ Epoxy Consumption Rate < 20%...△

[0371] 20% ≤ Epoxy Consumption Rate…×

[0372] Starting from the side rated "good", the values ​​are listed in the table in the order of ◎, 〇, △, ×.

[0373] (Storage stability of films obtained using epoxy resin compositions)

[0374] Films were prepared using any epoxy resin compositions from Examples 1-19 and Comparative Example 2, following the same method as described above (stability during film preparation). The films were then stored in an oven at 40°C for 7 days. The FT-IR spectra of the stored films were measured using the same method as described above (stability during film preparation), and the P2 / P1 values ​​in the aforementioned formula (3) were the values ​​after storage. The epoxy consumption rate after storage was calculated.

[0375] The following criteria will be used to evaluate the epoxy consumption rate after storage.

[0376] 0% ≤ Epoxy Consumption Rate < 10%...◎

[0377] 10% ≤ epoxy consumption rate < 15%...

[0378] 15% ≤ Epoxy Consumption Rate < 20%...△

[0379] 20% ≤ Epoxy Consumption Rate…×

[0380] Starting from the side rated "good", the values ​​are listed in the table in the order of ◎, 〇, △, ×.

[0381] (Stability when using epoxy resin compositions as curing accelerators to produce films)

[0382] A solution was prepared by mixing and dissolving 50 parts by weight of phenoxy resin (manufactured by InChem, trade name "PKHB"), 50 parts by weight of bisphenol A type liquid epoxy resin (manufactured by Mitsubishi Chemical, trade name "jER828"), and 100 parts by weight of MEK. 2.5 parts by weight of dicyandiamide (DICY) as a curing agent and 2 parts by weight of the epoxy resin compositions of Examples 1, 5, 10, and 15 as curing accelerators were then mixed into 100 parts by weight of this solution to prepare a mixing liquid for epoxy resin materials for films.

[0383] When using this mixing liquid to prepare a film for determining the aforementioned P20 / P10, the composition after removing dicyandiamide and microencapsulated curing agent as curing agents is used. Otherwise, the films of Examples 39 to 42 are prepared using the same method as described above (stability during film preparation), and the epoxy consumption rate is measured and evaluated.

[0384] The following criteria are used to evaluate the epoxy consumption rate.

[0385] 0% ≤ Epoxy Consumption Rate < 10%...◎

[0386] 10% ≤ epoxy consumption rate < 15%...

[0387] 15% ≤ Epoxy Consumption Rate < 20%...△

[0388] 20% ≤ Epoxy Consumption Rate…×

[0389] Starting from the side rated "good", the values ​​are listed in the table in the order of ◎, 〇, △, ×.

[0390] (Storage stability of films when epoxy resin compositions are used as curing accelerators)

[0391] Films were prepared using the epoxy resin compositions of Examples 1, 5, 10, and 15, using the same method as described above (stability of films during film preparation when epoxy resin compositions are used as curing accelerators).

[0392] Subsequently, the film was stored in an oven at 40°C for 7 days. For the stored film, the FT-IR spectrum was measured using the same method as described above (stability when using epoxy resin composition as curing accelerator to make film). The P2 / P1 value of the aforementioned formula (3) was the value after storage, and the epoxy consumption rate after storage was calculated.

[0393] The following criteria will be used to evaluate the epoxy consumption rate after storage.

[0394] 0% ≤ Epoxy Consumption Rate < 10%...◎

[0395] 10% ≤ epoxy consumption rate < 15%...

[0396] 15% ≤ Epoxy Consumption Rate < 20%...△

[0397] 20% ≤ Epoxy Consumption Rate…×

[0398] Starting from the side rated "good", the values ​​are listed in the table in the order of ◎, 〇, △, ×.

[0399] (Cureability of the film)

[0400] The film was prepared using the methods described above (stability when using the epoxy resin composition to prepare the film) and (stability when using the epoxy resin composition as a curing accelerator to prepare the film). Subsequently, the epoxy resin composition layer was transferred to aluminum foil and cured in an oven at 180°C for 1 hour.

[0401] Observe the appearance and cross-section of the cured material to determine whether it can be cured.

[0402] [Ingredient Records]

[0403] The following table shows components (C) and (D) from Tables 1 to 3.

[0404] It should be noted that the viscosity of component (C) was determined using the same method as the initial viscosity determination of the epoxy resin composition.

[0405] Ingredient (C):

[0406] PGE: Phenyl glycidyl ether (viscosity at 25°C: 6 mPa·s) (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0407] o-CGE: o-Tolyl Glycidyl Ether (viscosity at 25°C: 7 mPa·s) (manufactured by Sigma-Aldrich Japan)

[0408] tBPGE: tert-butylphenyl glycidyl ether (viscosity at 25°C: 20 mPa·s) (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0409] YED216D: 1,6-Hexanediol diglycidyl ether (viscosity at 25°C: 121 mPa·s) (manufactured by Mitsubishi Chemical Corporation, trade name)

[0410] Ingredient (D):

[0411] 3-Phenoxy-1,2-Propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0412] Cresol glycerol ether (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0413] 3-Phenoxy-1-propanol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0414] Other ingredients:

[0415] NEWPOL BPE-20: A polyol compound obtained by the addition reaction of bisphenol A with ethylene oxide (manufactured by Sanyo Chemical Industries, Ltd., trade name).

[0416] [Examples 1-19], [Comparative Examples 1-3]

[0417] The components are mixed according to the proportions shown in Tables 1 to 3, and the epoxy resin composition is prepared using the above method.

[0418] The properties of the prepared epoxy resin composition were determined using the methods described above.

[0419] [Table 1]

[0420]

[0421] [Table 2]

[0422]

[0423] [Table 3]

[0424]

[0425] When comparing the examples with Comparative Examples 1 and 2, it can be seen that by adding components (C) and (D), an epoxy resin composition with an excellent balance of properties can be obtained while maintaining excellent storage stability, thereby achieving low viscosity and improved reactivity.

[0426] When comparing Example 1 with Comparative Example 3, it can be seen that the compound having the structure of component (D) is effective in all aspects of storage stability, low viscosity, and improved reactivity.

[0427] When comparing Examples 1 and 4, it can be seen that when component (C) is PGE, it exhibits a better balance of properties in terms of low viscosity and reactivity.

[0428] When comparing Examples 5, 10, and 11, the following trend is observed: the more component (D) there is, the better the low viscosity; the less component (D) there is, the better the storage stability.

[0429] Comparing Examples 10, 15, and 16 reveals that increasing the amount of component (C) results in superior curing properties and storage stability. Conversely, comparing Example 1 with Example 5 shows that increasing component (C) leads to decreased storage stability. This is because Examples 10, 15, and 16 contain a more appropriate amount of component (D), thus minimizing its impact on storage stability. Furthermore, the stacking of component (C) within the shell contributes to improved storage stability. Additionally, increasing the amount of component (C) decreases viscosity, thereby enhancing the diffusivity of component (D) and the substance obtained by coordination of component (D) with the curing agent during the curing reaction, resulting in excellent curing properties. It should be noted that comparing Example 15 with Comparative Example 1 shows that even a small amount of component (D) enhances reactivity, indicating that component (D) acts as a catalyst.

[0430] Comparing Examples 5, 13, and 14 reveals that even by changing the ratio of bisphenol A type epoxy resin to bisphenol F type epoxy resin in component (A), an epoxy resin composition with an excellent balance of properties can be obtained. Furthermore, it is evident that the higher the ratio of bisphenol F type epoxy resin in component (A), the better the low viscosity and storage stability.

[0431] Table 4 shows the evaluation results of the curing zone test.

[0432] [Table 4]

[0433]

[0434] It can be seen that adding components (C) and (D) improves the cured area. Tables 5 and 6 show the evaluation results of the solvent resistance test.

[0435] [Table 5]

[0436]

[0437] [Table 6]

[0438]

[0439] When comparing the examples with Comparative Example 2, it can be seen that the solvent resistance is improved by adding component (C).

[0440] When comparing Example 1 with Example 5, it can be seen that the solvent resistance is improved by increasing the amount of component (C).

[0441] Furthermore, comparing Examples 5, 6, and 7 with Example 18 reveals that when component (C) is a compound with an aromatic ring, it exhibits excellent solvent resistance. Moreover, comparing Examples 5 and 6 with Example 7 shows that when component (C) is PGE and / or o-CGE, it displays superior solvent resistance compared to tBPGE. This can be attributed to the fact that the steric hindrance of the substituents in the aromatic ring is small, allowing for easier penetration into the capsule membrane and the formation of a denser network of stacked aromatic rings.

[0442] Furthermore, when comparing Examples 5 and 12 with Example 19, it can be seen that the compound with a diol structure at the end of component (D) has excellent solvent resistance.

[0443] Tables 7 and 8 show the results of tests on the stability during film production and the storage stability of films of Examples 20 to 38 and Comparative Example 4 obtained using the epoxy resin compositions of Examples 1 to 19 and Comparative Example 2.

[0444] [Table 7]

[0445]

[0446] [Table 8]

[0447]

[0448] When comparing Examples 20-38 with Comparative Example 4, it can be seen that by adding component (C), the stability of the film during production and the storage stability of the film are excellent.

[0449] When comparing Example 20 with Example 24, it can be seen that by increasing the amount of component (C) added, the stability during film production and the storage stability of the film are improved.

[0450] Comparing Examples 24, 25, and 26 with Example 37 reveals that when component (C) is a compound with an aromatic ring, the stability during film fabrication is excellent. Furthermore, comparing Examples 24, 25, and 26 reveals that when component (C) is PGE and / or o-CGE, both the stability during film fabrication and the storage stability of the film are superior compared to tBPGE.

[0451] When comparing Examples 24, 32, and 33, it can be seen that there is a tendency that the more bisphenol F type epoxy resin there is, the better the stability of the film during film production and the better the storage stability of the film.

[0452] Table 9 shows the evaluation results of the stability tests during film production and the storage stability tests of the films of Examples 39-42, in which the epoxy resin compositions of Examples 1, 5, 10, and 15 were used as curing accelerators.

[0453] [Table 9]

[0454]

[0455] Examples 39–42 demonstrate excellent stability during film fabrication and film preservation.

[0456] Tables 10 and 11 show the evaluation results of the curability tests of the films of Examples 20 to 42.

[0457] [Table 10]

[0458]

[0459] [Table 11]

[0460]

[0461] All films in Examples 20-42 exhibited excellent curability.

[0462] The above description pertains to this embodiment, but the present invention is not limited thereto and may be appropriately modified without departing from the scope of the invention.

[0463] This application incorporates, by reference, the contents of Japanese Patent Application No. 2021-114776 filed with the Japan Patent Office on July 12, 2021, and Japanese Patent Application No. 2021-133229 filed with the Japan Patent Office on August 18, 2021.

[0464] Industrial availability

[0465] The epoxy resin composition of the present invention is industrially applicable in insulating materials, sealing materials, adhesives, conductive materials, matrix resins for fiber-reinforced plastics, impregnation fixatives for motor coils, and other electrical and electronic components such as underfills. Furthermore, it is industrially applicable in films such as interlayer insulating films, thin-film solder resists, sealing sheets, conductive films, anisotropic conductive films, and thermally conductive films obtained by using the epoxy resin composition of the present invention as a curing agent or curing accelerator, as well as various paste materials, coating materials, and paints that can utilize excellent solvent-resistant insulating adhesive pastes, conductive pastes, anisotropic conductive pastes, and thermally conductive pastes.

Claims

1. An epoxy resin composition comprising: Component (A): Epoxy resin, Component (B): Microencapsulated curing agent, Ingredient (C): Reactive diluent, and Component (D): The compound represented by formula (3) below, In formula (3), R1~R9 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatoms, substituent containing halogen atoms, and halogen atoms. R1 to R9 may be chosen to be the same or different from each other, and the compound shown in formula (3) may be a fused-ring compound selected from any of R1 to R5 that exists in the same ring. in, R1~R5 do not contain epoxy groups and the structure of the following formula (5), i.e., terminal diols. Wherein, component (A) epoxy resin and / or component (C) reactive diluent contain an sp value of 9-14 (cal / cm). 3 ) 1 / 2 The compound, wherein component (D) contains an sp value of 7 (cal / cm³). 3 ) 1 / 2 Above and less than 20 (cal / cm) 3 ) 1 / 2 Compounds.

2. The epoxy resin composition according to claim 1, wherein, The component (D) is a compound represented by the following formula (4). In formula (4), R1~R8 are selected from one of the following groups: hydrogen, alkyl, unsaturated aliphatic group, aromatic group, substituent containing heteroatoms, substituent containing halogen atoms, and halogen atoms. R1 to R8 may be chosen to be the same or different from each other, and the compound shown in formula (4) may be a fused ring compound selected from any of R1 to R5 that exists in the same ring.

3. The epoxy resin composition according to claim 1 or 2, wherein, The total chlorine content in component (A) epoxy resin is above 0.01 ppm and below 2500 ppm.

4. The epoxy resin composition according to claim 1 or 2, wherein, The epoxy resin of component (A) contains at least bisphenol F type epoxy resin.

5. The epoxy resin composition according to claim 4, wherein, The epoxy resin of component (A) also includes bisphenol A type epoxy resin.

6. The epoxy resin composition according to claim 5, wherein, The amount of bisphenol F epoxy resin added is 5 parts by weight or more and 90 parts by weight or less, relative to a total of 100 parts by weight of the bisphenol F epoxy resin and the bisphenol A epoxy resin.

7. The epoxy resin composition according to claim 1 or 2, wherein, The microcapsule-type curing agent of component (B) comprises one or more amine curing agents selected from the group consisting of amine adduct systems, modified polyamine systems, aliphatic polyamine systems, heterocyclic polyamine systems, alicyclic polyamine systems, aromatic amine systems, polyamide amine systems, ketimine systems, and carbamate amine systems.

8. The epoxy resin composition according to claim 1 or 2, wherein, The core of the microencapsulated curing agent of component (B) has a sphericity of 0.93 or higher.

9. The epoxy resin composition according to claim 1 or 2, wherein, The reactive diluent (C) contains compounds having aromatic rings.

10. The epoxy resin composition according to claim 9, wherein, The reactive diluent of component (C) comprises a compound whose aromatic ring is monocyclic and monofunctional.

11. The epoxy resin composition according to claim 10, wherein, The reactive diluent of component (C) comprises one or more selected from the group consisting of styrene oxide, phenyl glycidyl ether, tolyl glycidyl ether, p-sec-butylphenyl glycidyl ether, and tert-butylphenyl glycidyl ether.

12. The epoxy resin composition according to claim 1 or 2, wherein, The content of the reactive diluent (C) in the epoxy resin composition is more than 1% by mass and less than 20% by mass.

13. The epoxy resin composition according to claim 12, wherein, The content of the reactive diluent (C) in the epoxy resin composition is more than 3% by mass and less than 15% by mass.

14. The epoxy resin composition according to claim 12, wherein, The content of the reactive diluent (C) in the epoxy resin composition is more than 4% by mass and less than 13% by mass.

15. The epoxy resin composition according to claim 12, wherein, The content of the reactive diluent (C) in the epoxy resin composition is more than 5% by mass and less than 12% by mass.

16. The epoxy resin composition according to claim 12, wherein, The content of the reactive diluent (C) in the epoxy resin composition is 6% by mass or more and 11% by mass or less.

17. The epoxy resin composition according to claim 1 or 2, wherein, The component (D) comprises one or more selected from the group consisting of 3-phenoxy-1-propanol, 3-phenoxy-1,2-propanediol, 3-phenoxy-1,3-propanediol, cresol glycerol ether (3-(o-tolyloxy)-1,2-propanediol), and guaiacol glycerol ether (3-(2-methoxyphenoxy)propane-1,2-diol).

18. The epoxy resin composition according to claim 1 or 2, wherein, The content of component (D) in the epoxy resin composition is more than 0.001% by mass and less than 5% by mass.

19. The epoxy resin composition according to claim 18, wherein, The content of component (D) in the epoxy resin composition is more than 0.005% by mass and less than 3% by mass.

20. The epoxy resin composition according to claim 18, wherein, The content of component (D) in the epoxy resin composition is more than 0.01% by mass and less than 2.5% by mass.

21. The epoxy resin composition according to claim 18, wherein, The content of component (D) in the epoxy resin composition is more than 0.012% by mass and less than 2% by mass.

22. The epoxy resin composition according to claim 1 or 2, wherein, The epoxy resin (A) and / or the reactive diluent (C) contain an SP value of 9-14 (cal / cm³). 3 ) 1 / 2 The compound, wherein component (D) contains an sp value of 9 (cal / cm³). 3 ) 1 / 2 Above and less than 18 (cal / cm) 3 ) 1 / 2 Compounds.

23. The epoxy resin composition according to claim 1 or 2, wherein, The epoxy resin (A) and / or the reactive diluent (C) contain an SP value of 9-14 (cal / cm³). 3 ) 1 / 2 The compound, wherein component (D) contains an sp value of 11 (cal / cm³). 3 ) 1 / 2 Above and less than 16 (cal / cm) 3 ) 1 / 2 Compounds.

24. A thin film having: Support body; and A resin composition layer formed on the support and comprising the epoxy resin composition according to any one of claims 1 to 23.

25. The thin film according to claim 24, wherein, The resin composition layer further includes component (E): a polymer for film formation.

26. The thin film according to claim 24 or 25, wherein, The film is selected from any one of the following groups: interlayer insulating film, thin-film solder resist, sealing sheet, conductive film, and thermally conductive film.

27. The film according to claim 24 or 25, wherein, The thin film is an anisotropic conductive thin film.

28. A method for manufacturing a thin film, comprising the steps described in any one of claims 24 to 27: After coating the support with a mixture containing at least the epoxy resin composition of any one of claims 1 to 23 and component (F) organic solvent, the component (F) organic solvent is dried at a temperature range of 50 to 160°C for a time range of 1 to 30 minutes.

29. A cured product, which is a cured product of the epoxy resin composition according to any one of claims 1 to 23.

30. A cured product, which is a cured product of the film according to any one of claims 24 to 27.

Images