Curing resin compositions and adhesives

Abstract

The objective of this invention is to provide a curable resin composition that is superior to conventional two-component or multi-component epoxy resin compositions. The curable resin composition comprises an epoxy resin, an epoxy curing agent, and polymer particles, (i) further comprising aluminum hydroxide of a specific particle size in a specific amount, or (ii) further comprising aluminum hydroxide and the polymer particles having a specific composition, or (iii) further comprising a compound having a specific composition and the epoxy curing agent having a specific composition.

Description

Technical Field

[0001] This invention relates to a two-component curable resin composition comprising epoxy resin, and an adhesive comprising the same. Background Technology

[0002] Various compositions are known as adhesives (e.g., Patent Document 1). Furthermore, cured products obtained by curing epoxy resin compositions exhibit excellent strength, heat resistance, water resistance, chemical resistance, and electrical insulation properties. Therefore, epoxy resin compositions have been widely used in industrial and civil engineering applications. Currently, various compositions have been developed as epoxy resin compositions (e.g., Patent Documents 2-4, etc.).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: WO2016-137303 Publication

[0006] Patent Document 2: WO2009-034966

[0007] Patent Document 3: WO2009-025991

[0008] Patent Document 4: Japanese Patent Application Publication No. 2017-149887 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, the existing technology described above is not sufficient as a two-component or multi-component epoxy resin composition, and there is still room for further improvement.

[0011] One embodiment of the present invention was made in view of the above-mentioned problems, and its object is to provide a new curable resin composition with better curability than the past as a two-component or multi-component epoxy resin composition.

[0012] Methods for solving problems

[0013] The inventors conducted in-depth research to solve the above-mentioned problems, and as a result, completed this invention.

[0014] That is, the curable resin composition of one embodiment of the present invention is a two-component curable resin composition, wherein the curable resin composition comprises a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D), and the curable resin composition further comprises polymer particles (B) and aluminum hydroxide (C), wherein the polymer particles (B) have a core-shell structure comprising a core layer and a shell layer, wherein the total weight of the aluminum hydroxide (C) in 100% by weight of the curable resin composition is 55% by weight or more and 85% by weight or less, and the average particle size of the aluminum hydroxide (C) is 11 μm or more and 200 μm or less.

[0015] In another embodiment of the present invention, the curable resin composition is a two-component curable resin composition comprising a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D). The curable resin composition further comprises polymer particles (B) and aluminum hydroxide (C). The polymer particles (B) have a core-shell structure comprising a core layer and a shell layer. The total weight of aluminum hydroxide (C) in 100% by weight of the curable resin composition is 55% by weight or more and 85% by weight or less. The average particle size of the polymer particles (B) is 0.15 μm or more and 0. For particles smaller than 0.30 μm, the weight ratio of the core layer to the shell layer in the polymer particles (B) (weight of the core layer / weight of the shell layer) is 65 / 35 to 92 / 8. The shell layer of the polymer particles (B) is a copolymer formed by polymerizing the following monomer components, wherein the monomer components contain more than 55 wt% of alkyl esters of (meth)acrylic acid with 1 to 4 carbon atoms per 100 wt%, and the monomer components contain 10 to 100 wt% of alkyl esters of (meth)acrylic acid with 1 carbon atom and 0 to 80 wt% of alkyl esters of (meth)acrylic acid with 4 carbon atoms per 100 wt%.

[0016] In another embodiment of the present invention, the curable resin composition is a two-component or multi-component curable resin composition, wherein the curable resin composition comprises a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), and the curable resin composition further comprises polymer particles (B) and a compound (G), wherein the polymer particles (B) have a core-shell structure comprising a core layer and a shell layer, and the compound (G) has (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, wherein the number of tertiary alkyl groups located at the adjacent positions of the phenolic hydroxyl groups in the compound (G) is 0 or 1 in one molecule, and the epoxy curing agent (D) is selected from at least one of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0017] The effects of the invention

[0018] According to one embodiment of the present invention, it is possible to achieve a curable resin composition that is superior to the past, which can be used as a two-component or multi-component epoxy resin composition. Detailed Implementation

[0019] The following describes one embodiment of the present invention, but the present invention is not limited thereto. The present invention is not limited to the configurations described below, and various modifications can be made within the scope shown in the claims. Furthermore, embodiments or examples obtained by appropriately combining the technical means disclosed in different embodiments or examples are also included within the technical scope of the present invention. Moreover, by combining the technical means disclosed in each embodiment, new technical features can be formed. It should be noted that all academic and patent documents recorded in this specification are incorporated herein by reference. Additionally, in this specification, unless otherwise specified, "A~B" indicating a numerical range means "A or more (inclusive of A and greater than A) and B or less (inclusive of B and less than B)".

[0020] [I. First Embodiment]

[0021] The first embodiment relates to a two-component curable resin composition comprising epoxy resin, and an adhesive comprising the same.

[0022] For electrical devices such as rechargeable batteries and semiconductors, the increasing functionality in recent years has led to a rise in heat generation, making heat dissipation crucial. This is especially true for rechargeable batteries like lithium-ion batteries used in wireless mobile devices and electric vehicle (EV) battery packs. During charging and discharging, heat accumulates inside the battery, causing its internal temperature to rise. Therefore, efficient heat dissipation is a critical issue related to battery reliability and lifespan. Patent Document 1 discloses a battery pack in which battery cells are fixed to a component housing using a thermally conductive adhesive.

[0023] In addition, as described in Patent Document 1, in order to improve safety against fires and other accidents that may occur due to heat accumulation during charging and discharging, the curable resin composition used in the above-mentioned equipment is required to exhibit flame retardancy and is expected to show a V-0 rating according to the UL 94V Test (Vertical Burning Test).

[0024] Furthermore, as described in Patent Document 1, EV batteries are structures that connect a large number of battery cells in parallel. Due to external impacts such as vehicle collisions, shear stress is applied. Therefore, the adhesive used to fix each battery cell to the battery casing requires high adhesion and impact resistance.

[0025] On the other hand, epoxy resins excel in many aspects, such as dimensional stability, mechanical strength, electrical insulation properties, heat resistance, water resistance, and chemical resistance of their cured products. Therefore, they are widely used in electrical equipment as adhesives, sealants, and other curable resin compositions.

[0026] Patent Document 2 discloses a technique for improving the toughness and impact resistance of a cured product by dispersing polymer particles in a curable resin composition with curable resins such as epoxy resin as the main component.

[0027] Furthermore, lithium-ion batteries have poor heat resistance, making it difficult to use heat-curing, single-component epoxy-based curable resin compositions. Patent Document 3, etc., discloses a two-component epoxy-based curable resin composition that can be cured at room temperature or near room temperature.

[0028] To improve the heat dissipation of electrical equipment, the addition of thermally conductive fillers such as aluminum hydroxide and alumina to the curable resin composition used in the equipment has been investigated. However, with the addition of thermally conductive fillers, the mechanical strength, toughness, and impact resistance of the cured product obtained by curing the resin composition sometimes decrease. Furthermore, the cured epoxy resins widely used in electrical equipment exhibit low fracture toughness and show signs of being very brittle.

[0029] The resin composition described in Patent Document 1 has insufficient impact resistance, leaving room for improvement. Furthermore, Patent Documents 2 and 3 do not disclose techniques for improving the impact resistance and adhesion of epoxy-curable resin compositions formed by combining epoxy resin with a large amount of aluminum hydroxide.

[0030] In view of the above situation, the object of the invention of the first embodiment is to provide a two-component curable resin composition that combines epoxy resin and aluminum hydroxide, and can produce a cured product exhibiting excellent thermal conductivity, flame retardancy, adhesive strength and impact peel resistance, and can be cured at low temperatures at or near room temperature.

[0031] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that by combining polymer particles (B) with a core-shell structure and aluminum hydroxide (C) with a specific average particle size in a specific weight ratio to a two-component curable resin composition containing a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D), a cured product exhibiting excellent thermal conductivity, flame retardancy, adhesive strength and impact peel resistance can be obtained.

[0032] That is, the invention of the first embodiment relates to a curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), wherein the first component and / or the second component further contain polymer particles (B) having a core-shell structure and aluminum hydroxide (C), wherein the total weight of the aluminum hydroxide (C) is 55% by weight or more and 85% by weight or less relative to the total weight of the curable resin composition, and the average particle size of the aluminum hydroxide (C) is 11 μm or more and 200 μm or less, and the curable resin composition is a two-component or multi-component type.

[0033] According to the curable resin composition of the first embodiment, the cured product obtained by using epoxy resin and a high amount of aluminum hydroxide exhibits excellent thermal conductivity, flame retardancy, and adhesive strength. Furthermore, in the curable resin composition of the first embodiment, by using aluminum hydroxide with a specific average particle size, the toughness-improving effect brought about by polymer particles with a core-shell structure can be effectively manifested. As a result, the cured product obtained from the curable resin composition of the first embodiment exhibits excellent impact resistance. That is, according to the first embodiment, a two-component curable resin composition can be provided that can produce a cured product exhibiting excellent thermal conductivity, flame retardancy, adhesive strength, and impact-peel adhesion, and can also be cured at room temperature or near-room temperature.

[0034] In other words, the first embodiment is a curable resin composition containing at least epoxy resin (A), core-shell polymer particles (B), aluminum hydroxide (C), and epoxy curing agent (D). The curable resin composition of the first embodiment is a two-component or multi-component curable resin composition that includes a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D) as essential components, and further, as needed, mixes other components such as colorant and curing modifier before use. Furthermore, the curable resin composition of the first embodiment further contains core-shell polymer particles (B) and aluminum hydroxide (C). The core-shell polymer particles (B) and aluminum hydroxide (C) are preferably contained in the first component and / or the second component, respectively. In addition to the first and second components, the curable resin composition of the first embodiment may also contain other components as needed.

[0035] In this specification, “epoxy resin (A)”, “polymer particles (B)”, “aluminum hydroxide (C)” and “epoxy curing agent (D)” are sometimes referred to as “(A) component”, “(B) component”, “(C) component” and “(D) component”, respectively.

[0036] In this specification, "adhesive strength" and "impact peel resistance" are collectively referred to as "adhesiveness".

[0037] Furthermore, in this specification, adhesive strength is evaluated using shear adhesive strength (MPa). That is, adhesive strength refers to the value of shear adhesive strength (MPa). The higher the value of the cured shear adhesive strength (MPa), the better the adhesive strength of the cured resin composition.

[0038] Furthermore, in this specification, impact peel adhesion can be evaluated according to ISO 11343 by measuring the dynamic splitting resistance at 23°C. That is, impact peel adhesion refers to the value of the dynamic splitting resistance (kN / m). The higher the value of the dynamic splitting resistance after curing, the better the impact peel adhesion of the cured resin composition.

[0039] <Epoxy Resin (A)>

[0040] The curable resin composition of the first embodiment contains an epoxy resin (A) as a curable resin in the first component. Various epoxy resins can be used as the epoxy resin. Examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, bisphenol S type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenolic varnish type epoxy resin, glycidyl ether type epoxy resin of bisphenol A propylene oxide adduct, hydrogenated bisphenol A (or F) type epoxy resin, fluorinated epoxy resin, flame-retardant epoxy resins such as tetrabromobisphenol A glycidyl ether, glycidyl ether type epoxy resin of p-hydroxybenzoic acid, m-aminophenol type epoxy resin, diaminodiphenylmethane epoxy resin, various alicyclic epoxy resins, N,N-diglycidylaniline, and N,N-diglycidyl-o-toluidine. The epoxy resins used include, but are not limited to, triglycidyl isocyanurate, divinylbenzene dioxide, resorcinol diglycidyl ether, polyalkylene glycol diglycidyl ether, glycol diglycidyl ether, diglycidyl esters of aliphatic polybasic acids, glycidyl ethers of di- or higher polyaliphatic alcohols such as glycerol, chelated modified epoxy resins, rubber modified epoxy resins, urethane modified epoxy resins, hydantoin-type epoxy resins, epoxides of unsaturated polymers such as petroleum resins, amino-containing glycidyl ether resins, and epoxy compounds obtained by adding bisphenol A (or F) or polybasic acids to the above-mentioned epoxy resins through an addition reaction. Commonly used epoxy resins may also be used. These epoxy resins may be used alone or in combination of two or more.

[0041] Among these, more specific examples of polyalkylene glycol diglycidyl ethers include polyethylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether. More specific examples of glycol diglycidyl ethers include neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and cyclohexanediol diglycidyl ether. More specific examples of diglycidyl esters of aliphatic polyacids include dimer acid diglycidyl esters, adipic acid diglycidyl esters, sebacic acid diglycidyl esters, and maleic acid diglycidyl esters. More specific examples of diglycidyl ethers of di- or higher polyaliphatic alcohols include trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, castor oil-modified polyglycidyl ether, propoxylated glycerol triglycidyl ether, and sorbitol polyglycidyl ether. Examples of epoxy compounds obtained by adding polybasic acids to epoxy resins include, for instance, the product of the addition reaction between tall oil fatty acid dimer (dimer acid) and bisphenol A type epoxy resin, as described in International Publication No. 2010-098950.

[0042] The aforementioned polyalkylene glycol diglycidyl ether, the aforementioned glycol diglycidyl ether, the aforementioned diglycidyl ester of aliphatic polyacid, and the aforementioned glycidyl ether of di- or higher polyaliphatic alcohols are epoxy resins with low viscosity. When used in combination with other epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin, they function as reactive diluents, improving the balance between the viscosity of the composition and the physical properties of the cured product. That is, the aforementioned epoxy resin (A) preferably contains polyepoxides as reactive diluents. On the other hand, as described later, although monoepoxides function as reactive diluents, they are not included in epoxy resin (A). The content of these epoxy resins that function as reactive diluents is preferably 0.5 to 30% by weight, more preferably 2 to 20% by weight, and even more preferably 5 to 15% by weight in component (A).

[0043] The aforementioned chelated modified epoxy resin is a reaction product of epoxy resin and a compound containing a chelating functional group (chelating ligand). When a curable resin composition containing chelated modified epoxy resin is used as an adhesive for vehicles, it can improve adhesion to metal substrate surfaces contaminated with oily substances. A chelating functional group is a functional group in a compound having multiple coordinating atoms within the molecule capable of coordinating with metal ions. Examples include phosphate groups (e.g., -PO(OH)2), carboxylic acid groups (-CO2H), sulfate groups (e.g., -SO3H), amino groups, and hydroxyl groups (especially hydroxyl groups adjacent to each other on an aromatic ring). Examples of chelating ligands include ethylenediamine, bipyridine, ethylenediaminetetraacetic acid, phenanthroline, porphyrin, and crown ethers. Commercially available chelated modified epoxy resins include ADEKA RESIN EP-49-10N manufactured by ADEKA. (A) The amount of chelated modified epoxy resin in the component is preferably 0.1 to 10% by weight, more preferably 0.5 to 3% by weight.

[0044] The aforementioned rubber-modified epoxy resin is a reaction product obtained by reacting rubber with an epoxy-containing compound, having an average of 1.1 or more, preferably 2 or more, epoxy groups per molecule. Examples of rubbers include: acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), hydrogenated nitrile butadiene rubber (HNBR), ethylene propylene rubber (EPDM), acrylic rubber (ACM), butyl rubber (IIR), butadiene rubber, polypropylene oxide, polyethylene oxide, polyoxyethylene, and other polyoxyethylene rubber polymers. These rubber polymers preferably have reactive groups such as amino, hydroxyl, or carboxyl groups at their terminals. The product obtained by reacting these rubber polymers and epoxy resins using known methods in appropriate proportions is a rubber-modified epoxy resin. From the viewpoint of the adhesive strength and impact-peel adhesion of the resulting cured resin composition, acrylonitrile-butadiene rubber-modified epoxy resin and polyoxyethylene-modified epoxy resin are preferred, and acrylonitrile-butadiene rubber-modified epoxy resin is more preferred. It should be noted that acrylonitrile-butadiene rubber modified epoxy resin can be obtained, for example, by reacting carboxyl-terminated NBR (CTBN) with bisphenol A type epoxy resin.

[0045] In the above-mentioned acrylonitrile-butadiene rubber modified epoxy resin, from the viewpoint of the adhesive strength and impact peel adhesion of the obtained cured resin composition, the content of acrylonitrile monomer component in the acrylonitrile-butadiene rubber is preferably 5 to 40% by weight, more preferably 10 to 35% by weight, and even more preferably 15 to 30% by weight. From the viewpoint of the operability of the obtained cured resin composition, it is particularly preferred to be 20 to 30% by weight.

[0046] In this specification, "operability of the curable resin composition" refers to the operability of using the curable resin composition (coating, etc.).

[0047] Additionally, for example, the addition reaction product of amino-terminated polyoxyethylene and epoxy resin (hereinafter also referred to as "adduct") is also included in rubber-modified epoxy resin. The aforementioned adduct can be easily manufactured by known methods, as described in U.S. Patent Nos. 5,084,532 and 6,015,865. Specific examples of the epoxy resin used in manufacturing the adduct include, for example, component (A) described above, preferably bisphenol A type epoxy resin, bisphenol F type epoxy resin, and more preferably bisphenol A type epoxy resin. Commercially available amino-terminated polyoxyethylene used in manufacturing the adduct can include, for example, Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, and Jeffamine T-5000 manufactured by Huntsman Corporation.

[0048] The number of epoxide reactive terminal groups per molecule of the above-mentioned rubber is preferably 1.5 to 2.5, more preferably 1.8 to 2.2. It should be noted that "epoxide reactive terminal groups" refers to terminal groups that are reactive with epoxy groups.

[0049] The number-average molecular weight of the rubber, calculated as the equivalent molecular weight of polystyrene as measured by GPC, is preferably 1,000 to 10,000, more preferably 2,000 to 8,000, and particularly preferably 3,000 to 6,000.

[0050] There are no particular limitations on the manufacturing method of rubber-modified epoxy resin. For example, it can be manufactured by reacting rubber with an epoxy-containing compound in a large amount of epoxy-containing compound. Specifically, it is preferable to react with an epoxy-containing compound in an amount of 2 equivalents or more relative to 1 equivalent of the epoxy reactive terminal groups in the rubber. More preferably, a sufficient amount of epoxy-containing compound is reacted so that the resulting product is a mixture of rubber and epoxy-containing compound adduct and free epoxy-containing compound. For example, rubber-modified epoxy resin can be manufactured by heating to a temperature of 100-250°C in the presence of a catalyst such as phenyl dimethylurea or triphenylphosphine. There are no particular limitations on the epoxy-containing compound used in manufacturing rubber-modified epoxy resin, but bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferred, and bisphenol A type epoxy resin is more preferred. It should be noted that if an excessive amount of epoxy-containing compound is used in the manufacture of rubber-modified epoxy resin, the unreacted epoxy-containing compound remaining after the reaction is not included in the rubber-modified epoxy resin described in this specification.

[0051] For rubber-modified epoxy resins, the epoxy resin can be modified by pre-reacting with a bisphenol component. The bisphenol component used for modification is preferably 3 to 35 parts by weight, more preferably 5 to 25 parts by weight, relative to 100 parts by weight of the rubber component in the rubber-modified epoxy resin. The cured product obtained by curing the curable resin composition containing the modified rubber-modified epoxy resin exhibits excellent adhesive durability after exposure to high temperatures and excellent impact resistance at low temperatures.

[0052] There is no particular limitation on the glass transition temperature (Tg) of the rubber-modified epoxy resin, but it is preferably below -25°C, more preferably below -35°C, further preferably below -40°C, and especially preferably below -50°C.

[0053] The number-average molecular weight of the rubber-modified epoxy resin, calculated based on the polystyrene-converted molecular weight as measured by GPC, is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000. The molecular weight distribution (ratio of weight-average molecular weight to number-average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

[0054] Rubber-modified epoxy resins can be used alone or in combination of two or more types.

[0055] (A) The amount of rubber-modified epoxy resin in the component is preferably 1 to 50% by weight, more preferably 2 to 40% by weight, further preferably 5 to 30% by weight, and particularly preferably 10 to 20% by weight.

[0056] The aforementioned urethane-modified epoxy resin is a reaction product obtained by reacting a compound containing a group and an epoxy group that are reactive with an isocyanate group with a urethane prepolymer containing an isocyanate group. Each molecule has an average of 1.1 or more epoxy groups, preferably 2 or more. For example, a urethane-modified epoxy resin can be obtained by reacting a hydroxyl-containing epoxy compound with a urethane prepolymer.

[0057] The number-average molecular weight of the urethane-modified epoxy resin, calculated based on the polystyrene-converted molecular weight as determined by GPC, is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000. The molecular weight distribution (ratio of weight-average molecular weight to number-average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

[0058] Carbamate-modified epoxy resins can be used alone or in combination of two or more.

[0059] (A) The amount of urethane-modified epoxy resin in the component is preferably 1 to 50% by weight, more preferably 2 to 40% by weight, further preferably 5 to 30% by weight, and particularly preferably 10 to 20% by weight.

[0060] Among these epoxy resins, those having at least two epoxy groups per molecule are preferred from the viewpoints of high curability, excellent flexibility after curing, and superior effect in improving impact and peel resistance brought about by the core-shell polymer particles (B). Compounds having two epoxy groups per molecule are particularly preferred.

[0061] As component (A), among the epoxy resins described above, bisphenol A type epoxy resin and bisphenol F type epoxy resin yield cured products with high elastic modulus, excellent heat resistance and adhesion, and are relatively inexpensive. Therefore, epoxy resin (A) is preferably bisphenol A type epoxy resin and / or bisphenol F type epoxy resin. Furthermore, from the perspective of obtaining a curable resin composition that provides a cured product with excellent heat resistance at a low cost, epoxy resin (A) is particularly preferred to be bisphenol A type epoxy resin.

[0062] Furthermore, among various epoxy resins, epoxy resins with an epoxy equivalent of less than 220 have high elastic modulus and heat resistance in the cured product. Therefore, it is preferred, more preferably, to have an epoxy equivalent of 90 or more and less than 210, and even more preferably to have an epoxy equivalent of 150 or more and less than 200.

[0063] In particular, bisphenol A type epoxy resin and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 are liquid at room temperature, and the resulting cured resin compositions have good workability, and are therefore preferred.

[0064] When component (A) contains bisphenol A type epoxy resin and bisphenol F type epoxy resin with an epoxy equivalent of 220 or more and less than 5000 in a range of 40% by weight or less, more preferably 20% by weight or less in 100% by weight of component (A), the resulting cured product has excellent impact resistance and is therefore preferred.

[0065] <Polymer particles with core-shell structure (B)>

[0066] The curable resin composition of the first embodiment contains polymer particles having a core-shell structure as component (B) in the first component and / or the second component described above. Here, "polymer particles (B) having a core-shell structure" means that the polymer particles (B) have a core layer and a shell layer.

[0067] When the curable resin composition contains component (B), the cured product (e.g., adhesive layer) exhibits excellent impact-peel adhesion due to the toughness-improving effect brought about by component (B). Furthermore, when the curable resin composition contains component (B), the cured product tends to have excellent adhesive strength. Component (B) may be contained only in the first component, only in the second component, or both. Component (B) may swell due to low-molecular-weight compounds such as component (D) contained in the second component. Therefore, from the viewpoint of storage stability of the composition, component (B) is preferably contained at least in the first component, and more preferably only in the first component. Hereinafter, "polymer particles (B) having a core-shell structure" will also be referred to as "core-shell polymer particles (B)".

[0068] The core-shell polymer particles (B) may or may not have epoxy groups in their shells. In other words, the shells of the core-shell polymer particles (B) may or may not have epoxy groups. From the perspective of excellent impact peel adhesion of the obtained cured product, the core-shell polymer particles (B) preferably have epoxy groups in their shells. When the shells of the core-shell polymer particles (B) have epoxy groups, from the viewpoint of impact peel adhesion of the obtained cured product, the content of epoxy groups in the shells relative to the total weight of the shells of the core-shell polymer particles (B) is preferably greater than 0 mmol / g and less than 2.0 mmol / g, more preferably more than 0.1 mmol / g and less than 2.0 mmol / g, and more preferably more than 0.3 mmol / g and less than 1.5 mmol / g. As a result, the aggregation of the core-shell polymer particles (B) is suppressed, and the core-shell polymer particles (B) can be dispersed in the cured product in the state of primary particles, which can be expected to result in improved impact peel adhesion of the cured product. When the shells have epoxy groups, component (B) is preferably included only in the first component. Furthermore, from the viewpoint of storage stability of the curable resin composition, the core-shell polymer particles (B) preferably do not have epoxy groups in the shell layer. When the core-shell polymer particles (B) are added to a second component containing an epoxy curing agent (D), which is described later and has reactivity with epoxy groups, component (B) preferably does not have epoxy groups in the shell layer.

[0069] The curable resin composition may (i) contain core-shell polymer particles (B) having epoxy groups in the shell in the first component and (ii) contain core-shell polymer particles (B) not having epoxy groups in the shell in the second component.

[0070] In the first embodiment, the particle size of the core-shell polymer particles (B) is not particularly limited. Considering industrial productivity, the volume average particle size (Mv) of the core-shell polymer particles (B) in the first embodiment is preferably 0.01 μm to 2.00 μm (10 nm to 2000 nm), more preferably 0.03 μm to 0.60 μm (30 nm to 600 nm), more preferably 0.05 μm to 0.40 μm (50 nm to 400 nm), more preferably 0.10 μm to 0.30 μm (100 nm to 300 nm), more preferably 0.15 μm to 0.30 μm, more preferably 0.16 μm to 0.28 μm, more preferably 0.17 μm to 0.27 μm, and even more preferably 0.18 μm to 0.25 μm. Regarding the volume average particle size (Mv) of the core-shell polymer particles (B), (a) when it is 0.01 μm or more, the viscosity of the curable resin composition decreases, thus improving workability; (b) when it is 2.00 μm or less, the polymerization time of component (B) is shortened, improving industrial productivity. It should be noted that in this specification, the volume average particle size (Mv) of the polymer particles can be measured using a Microtrac UPA150 (manufactured by Nikkiso Corporation) to measure the latex of the polymer particles.

[0071] When the core-shell polymer particles (B) in the curable resin composition have a half-value width of 0.5 times or more and less than 1 times the volume average particle size in their particle size distribution, the resulting curable resin composition is easy to operate at low viscosity and is therefore preferred.

[0072] From the viewpoint of easily achieving the aforementioned specific particle size distribution, it is preferable that the number distribution of the core-shell polymer particles (B) has two or more maxima. From the viewpoint of manufacturing labor and cost, it is more preferable that it has two to three maxima, and even more preferable that it has two maxima. Particularly preferred is that it includes 10 to 90% by weight of core-shell polymer particles with a volume average particle size of 10 nm or more and less than 150 nm, and 90 to 10% by weight of core-shell polymer particles with a volume average particle size of 150 nm or more and less than 2000 nm.

[0073] The core-shell polymer particles (B) are preferably dispersed in the curable resin composition as primary particles. In this specification, "the core-shell polymer particles are dispersed as primary particles" (hereinafter also referred to as primary dispersion) means that the core-shell polymer particles are dispersed substantially independently (without contact) from each other, and their dispersion state can be confirmed, for example, by dissolving a portion of the curable resin composition in a solvent such as methyl ethyl ketone and measuring its particle size using a particle size measuring device based on laser scattering.

[0074] The value of the volume average particle size (Mv) / number average particle size (Mn) obtained by the above particle size measurement is not particularly limited, but is preferably 3.0 or less, more preferably 2.5 or less, even more preferably 2.0 or less, and particularly preferably 1.5 or less. When the volume average particle size (Mv) / number average particle size (Mn) is 3.0 or less, it can be considered that the core-shell polymer particles (B) are well dispersed, and the physical properties of the obtained cured product, such as impact resistance and adhesion, become good.

[0075] It should be noted that the volume average particle size (Mv) / number average particle size (Mn) can be measured using a Microtrac UPA (manufactured by Nikkiso Corporation) and calculated by dividing Mv by Mn.

[0076] Furthermore, "stable dispersion" of the core-shell polymer particles refers to a state in which the core-shell polymer particles do not aggregate, separate, or precipitate in the continuous layer, and remain stably dispersed for a long time under normal conditions. Additionally, it is preferable that the distribution of the core-shell polymer particles in the continuous layer does not change substantially, and that "stable dispersion" can be maintained even when the composition is stirred to reduce viscosity by heating it within a safe range.

[0077] Core-shell polymer particles (B) can be used alone or in combination of two or more types.

[0078] The structure of the core-shell polymer particles (B) is not particularly limited, but it is preferable to have two or more layers. Alternatively, it may have a structure with three or more layers, including an intermediate layer covering the core layer and a shell layer further covering the intermediate layer.

[0079] The following is a detailed explanation of each layer of the core-shell polymer particle (B).

[0080] The Core Layer

[0081] To improve the toughness of the cured resin composition, the core layer is preferably an elastic core layer with rubber-like properties. To possess rubber-like properties, the gel content of the elastic core layer is preferably 60% by weight or more, more preferably 80% by weight or more, further preferably 90% by weight or more, and particularly preferably 95% by weight or more. It should be noted that the gel content mentioned in this specification refers to the ratio of the insoluble component to the total amount of the insoluble and soluble components when 0.5g of crumb obtained by coagulation and drying is impregnated in 100g of toluene and allowed to stand at 23°C for 24 hours, and then separated into insoluble and soluble components.

[0082] The core layer preferably comprises one or more selected from diene rubbers, (meth)acrylate rubbers, and organosiloxane rubbers. From the viewpoint of improving the impact peel adhesion of the resulting cured product, and considering that the viscosity increase over time due to swelling of the core layer caused by component (A) is less likely to occur because of its low affinity with epoxy resin (A), the core layer preferably comprises diene rubber.

[0083] (Diene rubber)

[0084] Examples of conjugated diene monomers constituting the aforementioned diene rubbers include 1,3-butadiene, isoprene, 2-chloro-1,3-butadiene, and 2-methyl-1,3-butadiene. These conjugated diene monomers can be used alone or in combination of two or more.

[0085] The content of the aforementioned conjugated diene monomer is preferably in the range of 50-100% by weight in the core layer, more preferably in the range of 70-100% by weight, and even more preferably in the range of 90-100% by weight. When the content of the conjugated diene monomer is 50% by weight or more, the impact peel adhesion of the obtained cured product can be improved.

[0086] Examples of vinyl monomers capable of copolymerizing with conjugated diene monomers include: vinyl aromatics such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; vinyl carboxylic acids such as acrylic acid and methacrylic acid; vinyl cyanides such as acrylonitrile and methacrylonitrile; halogenated vinyls such as vinyl chloride, vinyl bromide, and chloroprene; vinyl acetate; alkenes such as ethylene, propylene, butene, and isobutene; and multifunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene. These vinyl monomers can be used alone or in combination of two or more. Styrene is particularly preferred.

[0087] The content of the vinyl monomers that can copolymerize with the conjugated diene monomers is preferably in the range of 0 to 50% by weight of the core layer, more preferably in the range of 0 to 30% by weight, and even more preferably in the range of 0 to 10% by weight. When the content of the vinyl monomers that can copolymerize with the conjugated diene monomers is 50% by weight or less, the impact peel adhesion of the obtained cured product can be improved.

[0088] From the viewpoint of improving impact resistance and peel adhesion, and from the viewpoint of reducing viscosity increase over time due to core swelling due to low affinity with epoxy resin (A), diene rubbers are preferably butadiene rubbers using 1,3-butadiene, and / or styrene-butadiene rubbers as copolymers of 1,3-butadiene and styrene, more preferably butadiene rubbers. Furthermore, from the viewpoint of improving the transparency of the cured product by adjusting the refractive index, styrene-butadiene rubber is preferred.

[0089] ((meth)acrylate rubber)

[0090] The aforementioned (meth)acrylate rubber is preferably a rubber elastomer obtained by polymerizing a mixture of monomers containing 50-100% by weight of at least one monomer selected from (meth)acrylate monomers, and 0-50% by weight of other vinyl monomers capable of copolymerizing with (meth)acrylate monomers.

[0091] Examples of the aforementioned (meth)acrylate monomers include: (i) methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, dodecyl methacrylate, stearyl methacrylate, dodecyl methacrylate, etc., which are alkyl methacrylates; (ii) phenoxyethyl methacrylate, benzyl methacrylate, etc., which contain aromatic rings; and (iii) 2-hydroxyethyl methacrylate, propylene methacrylate, etc. The monomers include hydroxyalkyl methacrylates such as 4-hydroxybutyl methacrylate; glycidyl methacrylate, glycidyl methacrylate, and other glycidyl methacrylates; alkoxyalkyl methacrylates; allyl methacrylate and allyl methacrylate; and polyfunctional methacrylates such as monoethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and tetraethylene glycol dimethacrylate. These methacrylate monomers can be used alone or in combination of two or more. Ethyl methacrylate, butyl methacrylate, and 2-ethylhexyl methacrylate are preferred as methacrylate monomers.

[0092] Other vinyl monomers that can copolymerize with (meth)acrylate monomers include, for example: (i) vinyl aromatics such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; (ii) vinyl carboxylic acids such as acrylic acid and methacrylic acid; (iii) vinyl cyanides such as acrylonitrile and methacrylonitrile; (iv) halogenated vinyls such as vinyl chloride, vinyl bromide, and chloroprene; (v) vinyl acetate; (vi) alkenes such as ethylene, propylene, butene, and isobutylene; and (vii) multifunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene. These vinyl monomers can be used alone or in combination of two or more. From the viewpoint of easily increasing the refractive index, styrene is particularly preferred.

[0093] (Organosiloxane rubber)

[0094] Examples of the aforementioned organosiloxane rubbers include: (i) polysiloxane polymers composed of alkyl or aryl disubstituted siloxane units, such as dimethylsiloxy, diethylsiloxy, methylphenylsiloxy, diphenylsiloxy, and dimethylsiloxy-diphenylsiloxy; and (ii) polysiloxane polymers composed of alkyl or aryl monosubstituted siloxane units, such as organohydrosiloxy units in which a portion of the alkyl group in the side chain is replaced by a hydrogen atom. These polysiloxane polymers can be used individually or in combination of two or more. From the perspective of imparting heat resistance to the cured product, dimethylsiloxy, methylphenylsiloxy, and dimethylsiloxy-diphenylsiloxy are preferred, and from the perspective of easy availability, dimethylsiloxy is most preferred. In the case where the core layer is formed by organosiloxane rubber, in order not to impair the heat resistance of the cured product, the total amount of organosiloxane rubber is taken as 100% by weight, preferably containing 80% by weight or more (more preferably 90% by weight or more) of polysiloxane polymer.

[0095] To improve the toughness of the obtained cured product, the glass transition temperature (hereinafter sometimes simply referred to as "Tg") of the core layer is preferably below 0°C, more preferably below -20°C, further preferably below -40°C, and particularly preferably below -60°C.

[0096] Furthermore, the volume average particle size of the core layer is not particularly limited, but is preferably 0.03 μm to 2 μm, more preferably 0.05 μm to 1 μm, even more preferably 0.12 μm to 0.50 μm, even more preferably 0.12 μm to 0.28 μm, and even more preferably 0.14 to 0.25 μm. When the volume average particle size of the core layer is within this range, the core layer can be stably manufactured, and the heat resistance and impact resistance of the cured product become good. It should be noted that, in this specification, the volume average particle size of the core layer can be measured using a Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.) to measure the latex of the core layer.

[0097] In the core-shell polymer particles (B) of the first embodiment, the proportion of the core layer is not particularly limited. When the total amount of core-shell polymer particles (B) is set to 100% by weight, the proportion of the core layer is preferably 40% to 97% by weight, more preferably 60% to 95% by weight, further preferably 70% to 93% by weight, and particularly preferably 80% to 90% by weight. When the proportion of the core layer is 40% by weight or more, the impact peel adhesion of the resulting cured product can be improved. When the proportion of the core layer is 97% by weight or less, the core-shell polymer particles are less prone to aggregation, the cured resin composition has a lower viscosity, and the workability can be improved.

[0098] In the core-shell polymer particles (B) of the first embodiment, the weight ratio of the core layer to the shell layer (weight of core layer / weight of shell layer) is not particularly limited. From the viewpoint of improving the workability of the curable resin composition and improving the impact resistance and adhesion of the cured product, this ratio (weight of core layer / weight of shell layer) is preferably 65 / 35 to 92 / 8, more preferably 68 / 32 to 91 / 9, and even more preferably 70 / 30 to 90 / 10.

[0099] The core layer is mostly a single-layer structure, but it can also be a multi-layer structure formed by layers with rubber elasticity. Furthermore, in the case of a multi-layer core layer, the polymer composition of each layer can differ from one another within the scope disclosed above.

[0100] The Intermediate Layer

[0101] An intermediate layer may be formed between the core layer and the shell layer as needed. In particular, a rubber surface cross-linking layer may be formed as the intermediate layer. From the viewpoint of improving the toughness of the cured product and improving its impact-resistant peel adhesion, it is preferable to not contain an intermediate layer, and particularly preferable to not contain the following rubber surface cross-linking layer.

[0102] In the presence of an intermediate layer, the ratio of the intermediate layer to the core layer in 100 parts by weight is preferably 0.1 to 30 parts by weight, more preferably 0.2 to 20 parts by weight, further preferably 0.5 to 10 parts by weight, and particularly preferably 1 to 5 parts by weight.

[0103] The aforementioned rubber surface crosslinking layer is formed by polymerizing an intermediate layer polymer from rubber surface crosslinking layer components. These components include 30-100% by weight of a polyfunctional monomer having two or more free radical polymerizable double bonds within a single molecule, and 0-70% by weight of other vinyl monomers. This rubber surface crosslinking layer has the effect of reducing the viscosity of the curable resin composition and improving the dispersibility of the core-shell polymer particles (B) in component (A). Furthermore, increasing the crosslinking density of the core layer also improves the grafting efficiency of the shell layer.

[0104] Specific examples of the aforementioned multifunctional monomers include allyl (meth)acrylates, allyl alkyl (meth)acrylates, and other allyl alkyl (meth)acrylates, excluding conjugated diene monomers such as butadiene; allyloxyalkyl (meth)acrylates; multifunctional (meth)acrylates having two or more (meth)acrylate groups, such as (poly)ethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate; diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, etc., preferably allyl methacrylate and triallyl isocyanurate. In this specification, (meth)acrylate refers to acrylates and / or methacrylates.

[0105] Shell

[0106] The outermost shell of the core-shell polymer particles is a polymer obtained by polymerizing monomers to form the shell. The polymer constituting the shell (shell polymer) improves the compatibility of the core-shell polymer particles (B) with component (A) and enables the core-shell polymer particles (B) to be dispersed in the curable resin composition or its cured product as primary particles.

[0107] Such a shell polymer is preferably grafted onto the aforementioned core layer and / or intermediate layer. It should be noted that, hereinafter, "grafted onto the core layer" also includes grafting onto the intermediate layer when forming the intermediate layer on the core layer. More precisely, the monomer components used to form the shell layer are preferably grafted onto the core polymer forming the core layer (in the case of an intermediate layer, the core polymer also contains the intermediate layer polymer forming the intermediate layer; the same applies hereinafter), and the shell polymer and core polymer are substantially chemically bonded together (in the case of an intermediate layer, the shell polymer is also preferably chemically bonded to the intermediate layer polymer). That is, the shell polymer is preferably formed by grafting the aforementioned shell-forming monomers onto the core polymer in the presence of the core polymer, thereby grafting onto the core polymer and coating a portion or the entirety of the core polymer. This polymerization operation can be carried out by adding the shell polymer layer-forming monomers to the latex of the core polymer prepared in an aqueous polymer latex state and polymerizing it.

[0108] It should be noted that in the core-shell polymer particles (B), as long as at least a portion of the shell polymer forming the shell layer is grafted (graft-bonded) to the core polymer, the core and shell layers do not necessarily form a complete layered structure. In other words, the shell polymer may not cover the entire core layer. In the core-shell polymer particles (B), a portion of the shell polymer can enter the core layer. In the core-shell polymer particles (B), preferably a portion of the shell polymer covers the core layer; in other words, preferably a portion of the shell polymer exists on the outermost surface of the core-shell polymer particles (B) (forming the outermost layer).

[0109] The composition of the shell-forming monomer, i.e., the types and proportions of monomers included in the shell-forming monomer, is not particularly limited. From the viewpoint of the compatibility and dispersibility of the core-shell polymer particles (B) in the curable resin composition, aromatic vinyl monomers, vinyl cyanide monomers, or (meth)acrylate monomers are preferred as shell-forming monomers, with (meth)acrylate monomers being more preferred. It is particularly preferred that the shell-forming monomer includes methyl methacrylate. These shell-forming monomers can be used individually or in appropriate combinations.

[0110] In other words, the types and proportions of structural units contained in the shell are not particularly limited. From the viewpoint of the compatibility and dispersibility of the core-shell polymer particles (B) in the curable resin composition, the shell preferably contains structural units derived from one or more monomers selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylate monomers, and more preferably contains structural units derived from (meth)acrylate monomers. Particularly preferred is that the shell contains structural units derived from methyl methacrylate.

[0111] The total amount of aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylate monomers is preferably 10.0% to 99.5% by weight, more preferably 50.0% to 99.0% by weight, further preferably 65.0% to 98.0% by weight, particularly preferably 67.0% to 80.0% by weight, and most preferably 67.0% to 85.0% by weight in 100% of the monomers for shell formation.

[0112] In other words, the shell layer preferably contains, within 100% by weight, structural units derived from one or more monomers selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylate monomers, more preferably 50.0% by weight to 99.0% by weight, further preferably 65.0% by weight to 98.0% by weight, particularly preferably 67.0% by weight to 80.0% by weight, and most preferably 67.0% by weight to 85.0% by weight.

[0113] Specific examples of the aforementioned aromatic vinyl monomers include: styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, and other vinylbenzene derivatives.

[0114] Specific examples of the aforementioned vinyl cyanide monomers include acrylonitrile and methacrylonitrile.

[0115] Specific examples of the aforementioned (meth)acrylate monomers include: methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and other alkyl (meth)acrylates; hydroxyalkyl (meth)acrylates, etc.

[0116] Specific examples of the aforementioned hydroxyalkyl methacrylates include: hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, and other hydroxy-containing linear alkyl methacrylates (especially hydroxy-containing C1-6 alkyl methacrylates); caprolactone-modified hydroxy(meth)acrylates; hydroxy-containing branched alkyl methacrylates such as methyl α-(hydroxymethyl)acrylate and ethyl α-(hydroxymethyl)acrylate; and hydroxy-containing methacrylates such as mono(meth)acrylates of polyester diols (especially saturated polyester diols) obtained from dicarboxylic acids (such as phthalic acid) and diols (such as propylene glycol).

[0117] The shell layer of the first embodiment is preferably a copolymer formed by polymerizing a shell-forming monomer containing 55% or more of an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms in 100% by weight of the shell-forming monomer. In other words, the shell layer of the first embodiment preferably contains 55% or more of structural units derived from an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms in 100% by weight of the shell layer. The shell layer of the first embodiment is preferably a copolymer formed by polymerizing a monomer component containing 65% or more of an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms in 100% by weight of the shell-forming monomer, more preferably a copolymer formed by polymerizing a monomer component containing 75% or more of a monomer component, even more preferably a copolymer formed by polymerizing a monomer component containing 78% or more of a monomer component, and particularly preferably a copolymer formed by polymerizing a monomer component containing 83% or more of a monomer component. When the shell-forming monomer contains an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms in the above-described range, it has the advantage of improved operability of the curable resin composition.

[0118] Specific examples of alkyl esters of (meth)acrylate having 1 to 4 carbon atoms include: methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, and other alkyl esters of (meth)acrylate.

[0119] The shell-forming monomer of the first embodiment preferably contains, in 100% by weight, 10% to 100% by weight of an alkyl ester of (meth)acrylate having one carbon atom, and 0% to 80% by weight of an alkyl ester of (meth)acrylate having four carbon atoms. In other words, the shell of the first embodiment preferably contains 10% to 100% by weight of structural units derived from an alkyl ester of (meth)acrylate having one carbon atom, and 0% to 80% by weight of structural units derived from an alkyl ester of (meth)acrylate having four carbon atoms.

[0120] The shell-forming monomer of the first embodiment more preferably contains 11% to 95% by weight of an alkyl ester of (meth)acrylic acid with one carbon atom in 100% by weight, more preferably 12% to 92% by weight, further preferably 13% to 55% by weight, and particularly preferably 14% to 50% by weight in 100% by weight of the shell-forming monomer. The shell-forming monomer of the first embodiment preferably contains 1% to 89% by weight of an alkyl ester of (meth)acrylic acid having 4 carbon atoms in 100% by weight of the shell-forming monomer, more preferably 1% to 88% by weight, more preferably 1% to 87% by weight, more preferably 1% to 86% by weight, more preferably 1% to 78% by weight, more preferably 2% to 76% by weight, more preferably 5% to 76% by weight, more preferably 8% to 76% by weight, more preferably 20% to 74% by weight, more preferably 35% to 72% by weight, further preferably 35% to 60% by weight, and particularly preferably 35% to 50% by weight. When the shell-forming monomer constituting the shell layer of the core-shell polymer particle (B) contains an alkyl ester of (meth)acrylic acid with one carbon atom and / or an alkyl ester of (meth)acrylic acid with four carbon atoms within the range described above, the interaction between the core-shell polymer particle (B) and component (C) can be appropriately controlled. Therefore, the viscosity of the curable resin composition is suppressed to a very low level, which has the advantage of good operability.

[0121] As an alkyl ester of (meth)acrylate with one carbon atom, methyl methacrylate and methyl acrylate can be used. As an alkyl ester of (meth)acrylate with four carbon atoms, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, and tert-butyl methacrylate can be used.

[0122] From the viewpoint of improving the workability of the curable resin composition, the shell-forming monomer of the first embodiment preferably has both an alkyl ester of (meth)acrylate with one carbon atom and an alkyl ester of (meth)acrylate with four carbon atoms, more preferably containing 13% to 55% by weight of the alkyl ester of (meth)acrylate with one carbon atom and 20% to 74% by weight of the alkyl ester of (meth)acrylate with four carbon atoms. In other words, the shell of the first embodiment preferably has both structural units derived from an alkyl ester of (meth)acrylate with one carbon atom and structural units derived from an alkyl ester of (meth)acrylate with four carbon atoms, more preferably containing 13% to 55% by weight of the structural units derived from an alkyl ester of (meth)acrylate with one carbon atom and 20% to 74% by weight of the structural units derived from an alkyl ester of (meth)acrylate with four carbon atoms.

[0123] It should be noted that the shell-forming monomer of the first embodiment does not need to have a total of 100% by weight of alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms in 100% by weight of the shell-forming monomer. In other words, for the shell-forming monomer of the first embodiment, it is sufficient that the total of monomers other than (a) alkyl esters of (meth)acrylate with one carbon atom, (b) alkyl esters of (meth)acrylate with four carbon atoms, and (c) alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms in 100% by weight of the shell-forming monomer is 100% by weight. That is, the shell-forming monomer of the first embodiment may include monomers other than alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms.

[0124] When the shell-forming monomer contains aromatic vinyl monomers and / or vinyl cyanide monomers, that is, when the shell contains structural units derived from aromatic vinyl monomers and / or structural units derived from vinyl cyanide monomers, the compatibility and dispersibility of the core-shell polymer particles (B) in the curable resin composition become good. On the other hand, from the perspective of improving the workability of the curable resin composition by reducing the interaction between component (B) and component (C), in the first embodiment, the content of aromatic vinyl monomers in 100% by weight of the shell-forming monomer can be 30% by weight or less, 20% by weight or less, 10% by weight or less, 8% by weight or less, or 6% by weight or less. In other words, in the first embodiment, the content of structural units derived from aromatic vinyl monomers in 100% by weight of the shell can be 30% by weight or less, 20% by weight or less, 10% by weight or less, 8% by weight or less, or 6% by weight or less. Furthermore, from the viewpoint of improving the workability of the curable resin composition, in the first embodiment, the content of vinyl cyanide monomer in 100% by weight of the shell-forming monomer can be 10% by weight, 8% by weight or less, 5% by weight or less, 4% by weight or less, 3% by weight or less, or 2% by weight or less. In other words, in the first embodiment, the content of structural units derived from vinyl cyanide monomer in 100% by weight of the shell layer is preferably 10% by weight or less, 8% by weight or less, 5% by weight or less, 4% by weight or less, 3% by weight or less, or 2% by weight or less.

[0125] As a shell-forming monomer, it may further contain (meth)acrylate monomers with 5 or more carbon atoms. In other words, the shell may further contain structural units derived from (meth)acrylate monomers with 5 or more carbon atoms. Specific examples of (meth)acrylate monomers with 5 or more carbon atoms include 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, etc.

[0126] In order to ensure that the core-shell polymer particles (B) remain well dispersed in the cured product or curable resin composition without agglomeration, from the viewpoint of chemical bonding with component (A), the monomer for shell formation preferably contains a monomer with a reactive group, wherein the monomer containing the reactive group contains a group selected from epoxy, oxetyl, hydroxyl, amino, imide, carboxylic acid, carboxylic anhydride, cyclic ester, cyclic amide, benzo[a] The monomer has one or more of azino groups and cyanate groups, and is particularly preferred to have an epoxy group.

[0127] The shell layer is preferably a polymer formed by grafting and polymerizing a monomeric component containing epoxy groups onto the core layer (core polymer). According to this configuration, the resulting cured product has the advantage of excellent impact resistance, peel strength, and adhesion.

[0128] From the viewpoint of impact resistance, peel adhesion, and storage stability, the monomers used for shell formation preferably contain 0% to 90% by weight of epoxy groups, more preferably 1% to 50% by weight, further preferably 2% to 35% by weight, and particularly preferably 3% to 20% by weight.

[0129] In other words, the shell preferably has structural units derived from monomers having epoxy groups. Furthermore, the shell preferably contains 0% to 90% by weight of structural units derived from monomers having epoxy groups per 100% by weight, more preferably 1% to 50% by weight, further preferably 2% to 35% by weight, and particularly preferably 3% to 20% by weight.

[0130] Monomers with epoxy groups are preferably used for shell formation, and more preferably for shell formation only.

[0131] Furthermore, when using a multifunctional monomer having two or more free radical polymerizable double bonds as the shell-forming monomer, swelling of the core-shell polymer particles in the cured resin composition can be prevented, and the cured resin composition tends to have low viscosity and good workability, thus it is preferred. On the other hand, from the viewpoint of improving the toughness of the obtained cured product and improving the impact peel adhesion, it is preferable not to use a multifunctional monomer having two or more free radical polymerizable double bonds as the shell-forming monomer.

[0132] Of the 100% by weight of the shell-forming monomer, for example, it may contain 0% to 20% by weight of a multifunctional monomer, preferably 1% to 20% by weight, and more preferably 5% to 15% by weight.

[0133] Specific examples of monomers containing reactive groups, such as hydroxyl groups, include: hydroxyl linear alkyl esters of methacrylate (especially hydroxyl linear C1-6 alkyl esters of methacrylate), such as 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate; caprolactone-modified hydroxy(meth)acrylates; hydroxyl branched alkyl esters of methacrylate, such as methyl α-(hydroxymethyl)acrylate and ethyl α-(hydroxymethyl)acrylate; and hydroxyl-containing methacrylates such as mono(meth)acrylates of polyester diols (especially saturated polyester diols) obtained from dicarboxylic acids (phthalic acid, etc.) and diols (propylene glycol, etc.).

[0134] Specific examples of the monomers containing epoxy groups mentioned above include: glycidyl methacrylate, 4-hydroxybutyl methacrylate glycidyl ether, allyl glycidyl ether, and other vinyl monomers containing glycidyl groups.

[0135] As a specific example of the multifunctional monomer having two or more free radical polymerizable double bonds, monomers identical to the multifunctional monomers described above can be exemplified, preferably allyl methacrylate or triallyl isocyanurate.

[0136] The shell layer of the first embodiment is preferably a polymer of shell-forming monomers, for example, the following: a shell-forming monomer composed of (a) 0-50 wt% (preferably 1-50 wt%, more preferably 2-48 wt%) of aromatic vinyl monomers (especially styrene), (b) 0-50 wt% (preferably 0-30 wt%, more preferably 10-25 wt%) of vinyl cyanide monomers (especially acrylonitrile), (c) 0-100 wt% (preferably 5-100 wt%, more preferably 70-95 wt%) of (meth)acrylate monomers (especially methyl methacrylate), and (d) 1-50 wt% (preferably 2-35 wt%, more preferably 3-20 wt%) of epoxy-containing monomers (especially glycidyl methacrylate). This allows for a balanced and effective improvement in both toughness and mechanical properties.

[0137] Furthermore, the shell layer in the first embodiment is preferably a polymer of shell-forming monomers, for example, the following: a shell-forming monomer composed of (a) 10 to 100% by weight (preferably 11 to 95% by weight, particularly 14 to 50% by weight) of an alkyl ester monomer (especially butyl acrylate) having 1 carbon atom in (a) meth)acrylic acid, 0 to 80% by weight (preferably 1 to 78% by weight, particularly 35 to 72% by weight) of an alkyl ester monomer (especially styrene) having 4 carbon atom in (a) meth)acrylic acid, 30% or less by weight (preferably 10% or less by weight, more preferably 0% by weight) of an aromatic vinyl monomer (especially styrene), 10% or less by weight (preferably 5% or less by weight, more preferably 0% by weight) of a vinyl cyanide monomer (especially acrylonitrile), and 0 to 45% by weight (preferably 0 to 25% by weight, more preferably 3 to 20% by weight) of an epoxy group-containing monomer (especially glycidyl methacrylate), totaling 100% by weight. Therefore, it is possible to achieve a good balance between the desired improvement in resilience and operability.

[0138] These monomeric components can be used individually or in combination of two or more. In addition to the aforementioned monomeric components, the shell can also contain other monomeric components.

[0139] From the viewpoint of improving the workability of the curable resin composition, the glass transition temperature (hereinafter sometimes simply referred to as "Tg") of the shell layer is preferably -45°C or higher and 110°C or lower, more preferably -40°C or higher and 100°C or lower, further preferably -35°C or higher and 50°C or lower, and particularly preferably -30°C or higher and 10°C or lower.

[0140] The grafting rate of the shell layer is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. When the grafting rate is 70% or more, the curable resin composition can achieve a lower viscosity.

[0141] The grafting rate was calculated as follows. First, the aqueous latex containing the core-shell polymer particles was coagulated / dehydrated and then dried to obtain a powder of the core-shell polymer particles. Next, 2g of the core-shell polymer particle powder was immersed in 100g of methyl ethyl ketone (MEK) at 23°C for 24 hours. The MEK-soluble and MEK-insoluble components were then separated, and the methanol-insoluble component was further separated from the MEK-soluble component. Then, the grafting rate was calculated by determining the ratio of the MEK-insoluble component to the total amount of the MEK-insoluble and methanol-insoluble components.

[0142] Manufacturing Methods for Core-Shell Polymer Particles

[0143] (Methods for manufacturing the core layer)

[0144] The core layer constituting the core-shell polymer particle (B) can be formed, for example, by emulsion polymerization, suspension polymerization, micro-suspension polymerization, etc., and the methods described in International Publication No. 2005 / 028546 and International Publication No. 2006 / 070664 can be used.

[0145] (Methods for forming the shell and intermediate layer)

[0146] The intermediate layer can be formed by polymerizing the monomers for forming the intermediate layer using known free radical polymerization. When the rubber elastomer constituting the core layer is obtained in the form of an emulsion, the polymerization of the monomers for forming the intermediate layer is preferably carried out by emulsion polymerization.

[0147] The shell can be formed by polymerizing the shell-forming monomers using known free radical polymerization. When the polymer particle precursor is obtained in the form of an emulsion or by coating the core layer with an intermediate layer, the polymerization of the shell-forming monomers is preferably carried out by emulsion polymerization, for example, by the method described in International Publication No. 2005 / 028546.

[0148] Examples of emulsifiers (dispersants) that can be used in emulsion polymerization include: alkyl or aryl sulfonic acids, such as dioctyl sulfosuccinate and dodecylbenzene sulfonic acid; alkyl or aryl sulfuric acids, such as dodecyl sulfate; alkyl or aryl sulfuric acids, such as dodecyl sulfate; alkyl or aryl ether sulfuric acids; alkyl or aryl substituted phosphoric acid; alkyl or aryl ether substituted phosphoric acid; N-alkyl or aryl sarcosine, such as dodecyl sarcosine; alkyl or aryl carboxylic acids, such as oleic acid and stearic acid; alkyl or aryl ether carboxylic acids; and various acids such as alkali metal salts or ammonium salts of these acids; nonionic emulsifiers (dispersants) such as alkyl or aryl substituted polyethylene glycol; and dispersants such as polyvinyl alcohol, alkyl-substituted cellulose, polyvinylpyrrolidone, and polyacrylic acid derivatives. These emulsifiers (dispersants) can be used alone or in combination of two or more.

[0149] The amount of emulsifier (dispersant) used should preferably be reduced as long as it does not impair the dispersion stability of the aqueous latex of polymer particles. Furthermore, higher water solubility of the emulsifier (dispersant) is preferred. Higher water solubility facilitates the washing and removal of the emulsifier (dispersant) from the water, easily preventing adverse effects on the final cured product.

[0150] When using emulsion polymerization, known initiators such as 2,2'-azobisisobutyronitrile, hydrogen peroxide, potassium persulfate, and ammonium persulfate can be used as thermally decomposable initiators.

[0151] Alternatively, a redox initiator can be used, wherein the combination of the redox initiator uses organic peroxides such as isopropyl tert-butyl peroxide, terpene hydrogen peroxide, cumene hydrogen peroxide, dicumene peroxide, tert-butyl hydrogen peroxide, di-tert-butyl peroxide, and tert-hexyl peroxide; inorganic peroxides such as hydrogen peroxide, potassium persulfate, and ammonium persulfate; reducing agents such as sodium formaldehyde sulfoxylate and glucose added as needed; transition metal salts such as ferric sulfate (II) added as needed; chelating agents such as disodium ethylenediaminetetraacetate added as needed; and phosphorus-containing compounds such as sodium pyrophosphate added as needed.

[0152] When using redox initiators, polymerization can be carried out at low temperatures where the peroxides do not substantially undergo thermal decomposition, allowing for a wide range of polymerization temperatures, which is preferable. Specifically, organic peroxides such as cumene hydroperoxide, dicumene peroxide, and tert-butyl hydroperoxide are preferred as redox initiators. Regarding the amount of the initiator, when using a redox initiator, the amounts of the reducing agent / transition metal salt / chelating agent, etc., can be used within known ranges. Furthermore, when polymerizing monomers having two or more free radical polymerizable double bonds, the amounts can be used within known ranges. Surfactants can also be added, and their use is also within known ranges.

[0153] The polymerization temperature, pressure, deoxidation, and other conditions during polymerization can be within a known range. Furthermore, the polymerization of the intermediate layer forming monomer can be carried out in one step or in two or more steps. For example, methods can be employed such as adding the intermediate layer forming monomer to the emulsion of the rubber elastomer constituting the elastic core layer in a single step, adding it continuously, or polymerizing the emulsion of the rubber elastomer constituting the elastic core layer after adding it to a reactor in which the intermediate layer forming monomer has been pre-added.

[0154] When using core-shell polymer particles as component (B), from the perspective of balancing the ease of handling of the obtained curable resin composition and the improvement effect on the toughness of the obtained cured product, the content of core-shell polymer particles in the curable resin composition relative to 100 parts by weight of epoxy resin (A) is preferably 1 to 100 parts by weight, more preferably 5 to 90 parts by weight, further preferably 10 to 80 parts by weight, even more preferably 20 to 70 parts by weight, and particularly preferably 30 to 60 parts by weight.

[0155] <Aluminum hydroxide (C)>

[0156] The curable resin composition of the first embodiment contains aluminum hydroxide as component (C) in the first component and / or the second component described above. When the curable resin composition of the first embodiment contains component (C), the resulting cured product has the advantages of excellent thermal conductivity and flame retardancy (e.g., flame retardancy evaluated by vertical burning test (UL94)).

[0157] In the first embodiment, the total weight of aluminum hydroxide (C) must be 55% by weight or more and 85% by weight or less relative to the total weight of the curable resin composition.

[0158] Component (C) may be contained only in the first component, only in the second component, or in both the first and second components. From the viewpoint of incorporating a large amount of component (C) into the curable resin composition, component (C) is preferably contained at least in the first component, and more preferably in both the first and second components.

[0159] Aluminum hydroxide is a white crystalline powder represented by the chemical formula Al(OH)3 or Al2O3·3H2O, generally manufactured from bauxite using the Bayer process. Aluminum hydroxide exists as a fraction with products of various average particle sizes.

[0160] It is very important that the aluminum hydroxide used in the first embodiment has an average particle size of 11 μm or more and 200 μm or less.

[0161] Component (C) may be coupled to improve its adhesion to component (A). This improves the impact resistance, strength, water resistance, and other physical properties of the resulting cured product. There are no particular limitations on these coupling agents; examples include silane coupling agents, chromium coupling agents, titanium coupling agents, aluminum coupling agents, and zirconium coupling agents, among which silane coupling agents are preferred, and epoxy silane coupling agents are more preferred. Furthermore, the coupling agent may be used alone or in combination of two or more.

[0162] In the first embodiment, from the viewpoint of balancing the impact resistance and adhesive strength of the obtained cured product, and from the viewpoint of suppressing the sedimentation of component (C) in the curable resin composition before curing, the average particle size of component (C) must be 11 μm or more and 200 μm or less, preferably 12 μm or more and 150 μm or less, more preferably 13 μm or more and 100 μm or less, further preferably 15 μm or more and 50 μm or less, and particularly preferably 17 μm or more and 30 μm or less.

[0163] It should be noted that, in this specification, the average particle size of component (C) can be determined by measuring with a laser scattering particle size analyzer, and is the particle size (Dp50) corresponding to a cumulative particle size distribution of 50% by volume.

[0164] When using multiple (C) components with different average particle sizes, the overall average particle size of the (C) components can be calculated by weighted averaging the values ​​obtained by multiplying the weight % of each (C) component relative to the total amount of (C) components by its respective average particle size.

[0165] In the first embodiment, from the viewpoint of improving the properties of the obtained cured product (thermal conductivity, flame retardancy, adhesive strength, and impact resistance) and the viewpoint of improving the workability of the composition before curing, the total weight of aluminum hydroxide (C) relative to the total weight of the curable resin composition must be 55% by weight or more and 85% by weight or less, preferably 57% by weight or more and 80% by weight or less, more preferably 60% by weight or more and 76% by weight or less, further preferably 62% by weight or more and 73% by weight or less, and particularly preferably 65% ​​by weight or more and 70% by weight or less.

[0166] From the viewpoint of improving the properties of the cured product (thermal conductivity, flame retardancy, bond strength, and impact resistance) and improving the workability of the composition before curing, the content (composition amount) of the aluminum hydroxide (C) relative to 100 parts by weight of the epoxy resin (A) is preferably 250 parts by weight or more and 750 parts by weight or less, more preferably 300 parts by weight or more and 700 parts by weight or less, further preferably 350 parts by weight or more and 650 parts by weight or less, and particularly preferably 400 parts by weight or more and 600 parts by weight or less. Component (C) can be used alone or in combination of two or more.

[0167] As described above, polymer particles (B) with a core-shell structure and aluminum hydroxide (C) are preferably included in the first component and / or the second component, respectively. In this case, polymer particles (B) and aluminum hydroxide (C) may be included in the same component or may not be included in the same component. When components (B) and (C) are included, it is preferable to include components (B) and (C) as the first component and component (C) as the second component.

[0168] It should be noted that in the first embodiment, component (C) is incorporated in the curable resin composition at a rate of 55% by weight or more and 85% by weight or less. However, in the first embodiment, by setting the average particle size of component (C) to 11 μm or more and 200 μm or less, the effect of improving impact resistance brought about by component (B) described above can be maintained at a high level. The reason for this is as follows, which is reasonable based on theoretical speculation about the plastic deformation region related to the added rubber particle system (see Kishi et al., "Journal of the Japan Society for Adhesion, Vol. 40, No. 5, 177-183").

[0169] Plastic deformation region r of plane strain field p Using the Irwin method to apply the resin toughness value K IC The tensile yield stress σ is expressed as r p =1 / 6π×(K) IC / σ) 2 Here, K will be used as a two-component epoxy adhesive toughened with core-shell polymer particles. IC σ is assumed to be 1.5 MPa·m. 1 / 2 At 50 MPa, r p The plastic deformation region is 48 μm. p It is roughly tens to 100 μm in size.

[0170] On the other hand, in the curable resin composition of the first embodiment, aluminum hydroxide (C) is highly filled in the range of 55% by weight or more and 85% by weight or less. When aluminum hydroxide with a small particle size of about a few μm is used, the distance between the aluminum hydroxide particles is about a few μm, which cannot ensure a sufficient plastic deformation area. With aluminum hydroxide particles larger than 10 μm, a certain degree of plastic deformation area can be gradually ensured, and it can be inferred that the toughness improvement effect brought about by the core-shell polymer particles (B) is exhibited.

[0171] <Thermal conductive fillers other than aluminum hydroxide>

[0172] The curable resin composition of the first embodiment may contain thermally conductive fillers other than aluminum hydroxide. Examples include: silicon dioxide, aluminum oxide, aluminum nitride, boron nitride, silicon nitride, ZnO, SiC, and BeO.

[0173] The content of thermally conductive filler other than aluminum hydroxide in the curable resin composition is preferably 1 to 300 parts by weight, more preferably 2 to 200 parts by weight, and particularly preferably 5 to 100 parts by weight relative to 100 parts by weight of epoxy resin (A).

[0174] <Flame retardants other than aluminum hydroxide>

[0175] The curable resin composition of the first embodiment may contain flame retardants other than aluminum hydroxide. Examples include: magnesium hydroxide, ammonium polyphosphate, tricresyl phosphate, triethyl phosphate, triphenyl phosphate, trichloropropyl phosphate, dimethyl methylphosphonate, brominated polyether polyol, ammonium carbonate, and melamine cyanurate.

[0176] The content of flame retardant other than aluminum hydroxide in the curable resin composition is preferably 1 to 100 parts by weight, more preferably 2 to 70 parts by weight, and particularly preferably 5 to 50 parts by weight relative to 100 parts by weight of epoxy resin (A).

[0177] <Epoxy Curing Agent (D)>

[0178] The curable resin composition of the first embodiment contains an epoxy curing agent as component (D) in the second component.

[0179] Component (D) is a compound (including oligomers or polymers) containing active hydrogen groups, which can react with epoxy resin (A) to form crosslinks even at low temperatures at room temperature.

[0180] Epoxy curing agent (D) exhibits reactivity with epoxy groups near room temperature (e.g., below 5°C to 50°C). Compared to heat-curing epoxy curing agents, epoxy curing agent (D) demonstrates low-temperature reactivity with epoxy groups. By combining polymer particles (B) and the compound (G) described later, epoxy curing agent (D) achieves both excellent rapid curing and good bond strength without requiring heat treatment at temperatures exceeding 50°C.

[0181] The epoxy curing agent (D) in the first embodiment is not particularly limited, and various epoxy curing agents can be used. Examples of epoxy curing agents (D) in the first embodiment include: (a) aromatic amines, aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers and amino-terminated butadiene nitrile rubbers, and (a) their modified forms, i.e., amine curing agents; and (b) thiol curing agents; etc. Among the epoxy curing agents (D) in the first embodiment, amine curing agents are more preferred from the viewpoint of the adhesive strength of the obtained cured product.

[0182] Regarding the epoxy curing agent (D) of the first embodiment, from the viewpoint of room temperature curing properties (rapid curing properties) of amine curing agents, (a) it is preferable to include one or more selected from aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubbers; (b) more preferably, it is selected from one or more selected from aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubbers, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubbers. Regarding the epoxy curing agent (D) of the first embodiment, among the amine curing agents, (a) from the viewpoint of the impact resistance of the obtained cured product, (a-1) it is preferable to include one or more selected from terminal amino polyethers and terminal aminobutyronitrile rubber, (a-2) more preferably one or more selected from terminal amino polyethers and terminal aminobutyronitrile rubber, (b) further from the viewpoint of curability, it is more preferable to include terminal aminobutyronitrile rubber, and even more preferably terminal aminobutyronitrile rubber. Regarding the epoxy curing agent (D) of the first embodiment, among the amine curing agents, (a) from the viewpoint of the adhesive strength of the obtained cured product, (a-1) it is preferable to include one or more selected from alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber; (a-2) it is more preferably selected from one or more selected from alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber; (b) further from the viewpoint of curability, (b-1) it is more preferably selected from one or more selected from alicyclic amines and amino-terminated nitrile rubber; (b-2) it is more preferably selected from one or more selected from alicyclic amines and amino-terminated nitrile rubber. From the viewpoint of the adhesive strength and curing properties of the obtained cured product, the epoxy curing agent (D) of the first embodiment more preferably includes at least one selected from alicyclic amines, terminating aminobutadiene nitrile rubber, modified alicyclic amines and modified terminating aminobutadiene nitrile rubber, and even more preferably at least one selected from alicyclic amines, terminating aminobutadiene nitrile rubber, modified alicyclic amines and modified terminating aminobutadiene nitrile rubber.

[0183] Examples of aromatic amines mentioned above include: m-phenylenediamine, diaminodiphenylmethane, and diaminodiphenyl sulfone.

[0184] Examples of aliphatic amines mentioned above include: chain aliphatic polyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropyldiamine, diethylaminopropylamine, and hexamethylenediamine, as well as aliphatic aromatic amines such as m-phenylenediamine.

[0185] Examples of the aforementioned alicyclic amines include: N-aminoethylpiperazine, bis(4-amino-3-methylcyclohexyl)methane, montanane diamine, isophorone diamine, 4,4'-diaminodicyclohexylmethane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, which is a type of spirocyclic acetal diamine, norbornene diamine, tricyclodecane diamine, 1,3-diaminomethylcyclohexane, etc.

[0186] The aforementioned amide amines are compounds formed by the condensation of tall oil fatty acid dimers (dimer acids) with polyamines such as triethylenetetramine and tetraethylenepentamine. Commercially available amide amines include Versamid 140 and Versamid 115.

[0187] The aforementioned terminal amino polyethers are polyethers containing a polyether backbone and preferably having 1 to 4 (more preferably 1.5 to 3) amino and / or imino groups per molecule. Examples of commercially available terminal amino polyethers include Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, and Jeffamine T-5000 manufactured by Huntsman Corporation.

[0188] The aforementioned amino-terminated nitrile butadiene rubber is a polybutadiene / acrylonitrile copolymer that preferably has 1 to 4 (more preferably 1.5 to 3) amino groups and / or imino groups per molecule on average, and has an acrylonitrile monomer content of 5 to 40% by mass (more preferably 10 to 35% by mass, and even more preferably 15 to 30% by mass) in the main chain. Examples of commercially available amino-terminated rubbers include Hypro 1300X16 ATBN manufactured by CVC Corporation.

[0189] Examples of modifiers for amine curing agents include polyamine epoxy resin adducts, which are the reaction products of various polyamines such as aliphatic amines and alicyclic amines with less than an equal amount of epoxy resin, or ketimines, which are the dehydration reaction products of polyamines with ketones such as methyl ethyl ketone and isobutyl methyl ketone.

[0190] More specifically, examples of the aforementioned thiol-based curing agents include: pentaerythritol tetra(3-mercaptobutyrate), 1,4-bis(3-mercaptobutoxy)butane, 1,3,5-tris(2-(3-sulfonylbutyryloxy)ethyl)-1,3,5-triazine-2,4,6-trione, trimethylolpropane tri(3-mercaptobutyrate), thiol-terminated polyethers, and thiol-terminated polysulfides.

[0191] From the viewpoint of the rapid curing properties of the curable resin composition and the adhesive strength and impact resistance of the resulting cured product, the ratio of the number of moles of epoxy groups in the epoxy resin (A) to the number of moles of active hydrogen groups in the epoxy curing agent (D) (the number of moles of epoxy groups / the number of moles of active hydrogen groups) is preferably 0.5 or more and 1.6 or less, more preferably 1.1 or more and 1.6 or less, even more preferably 1.1 or more and 1.5 or less, and particularly preferably 1.2 or more and 1.4 or less.

[0192] From the viewpoint of balancing the adhesive strength and impact resistance of the cured product, and from the viewpoint of the ease of mixing when the first component and the second component are mixed, the content (compounding amount) of the epoxy curing agent (D) relative to 100 parts by weight of the epoxy resin (A) is preferably 15 parts by weight or more and 300 parts by weight or less, more preferably 20 parts by weight or more and 200 parts by weight or less, further preferably 30 parts by weight or more and 150 parts by weight or less, and particularly preferably 40 parts by weight or more and 100 parts by weight or less. Component (D) can be used alone or in combination of two or more.

[0193] The curable resin composition of the first embodiment may or may not contain aromatic amines. From the perspective of excellent tensile properties of the resulting cured product upon heating, the curable resin composition of the first embodiment is preferably substantially free of aromatic amines. In this specification, "substantially free of aromatic amines" means that the content of aromatic amines in 100 parts by weight of the curable resin composition is 1000 ppm or less. Examples of aromatic amines include m-phenylenediamine, diaminodiphenylmethane, and diaminodiphenyl sulfone.

[0194] <(D) Epoxy curing agents that exhibit activity at high temperatures>

[0195] Within a range that does not impair the curing speed of the curable resin composition of the first embodiment, epoxy curing agents that exhibit activity at high temperatures may be included, excluding epoxy curing agents containing active hydrogen groups capable of reacting with epoxy resin at low temperatures (such as the aforementioned amine curing agents and thiol curing agents). Examples of epoxy curing agents exhibiting activity at high temperatures include: acid anhydride curing agents; boron trifluoride-amine complexes; dicyandiamide; organic acid hydrazides, etc.

[0196] Compared with amine curing agents, the above-mentioned anhydride curing agents require high temperatures, have a long pot life, and produce cured products with a good balance of electrical, chemical, and mechanical properties. More specifically, anhydride curing agents include: polysaccharide polyanhydride, polyazelite polyanhydride, succinic anhydride, citraconic anhydride, itaconic anhydride, alkenyl-substituted succinic anhydride, dodecenyl succinic anhydride, maleic anhydride, triamic anhydride, nadic anhydride, methyl nadic anhydride, linoleic acid adducts based on maleic anhydride, alkyl-terminated alkylene tetrahydrophthalic anhydride, methyl tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, pyromellitic dianhydride, trimellitic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, dichloromaleic anhydride, chlorinated nadic anhydride, and chlorendic anhydride, as well as maleic anhydride-grafted polybutadiene, etc.

[0197] More specific examples of the aforementioned boron trifluoride-amine complexes include: boron trifluoride-monoethylamine, boron trifluoride-piperidine, boron trifluoride-triethylamine, and boron trifluoride-aniline.

[0198] More specifically, examples of the aforementioned organic acid hydrazides include: adipic acid hydrazide, stearic acid hydrazide, isophthalic acid hydrazide, and semicarbazide.

[0199] The content (composition amount) of epoxy curing agent that exhibits activity at high temperature in the curable resin composition, excluding component (D), is preferably 0.1 parts by weight or more and 30 parts by weight or less, more preferably 0.5 parts by weight or more and 20 parts by weight or less, further preferably 1 part by weight or more and 15 parts by weight or less, and particularly preferably 2 parts by weight or more and 10 parts by weight or less, relative to 100 parts by weight of the epoxy resin (A) described above.

[0200] <Epoxy Curing Accelerator (E)>

[0201] The curable resin composition of the first embodiment may contain an epoxy curing accelerator (E) in the first component and / or the second component described above. Component (E) is a compound that does not readily react with the epoxy resin (A) to form crosslinks, but can accelerate the curing reaction based on the epoxy resin (A) and the epoxy curing agent (D). Component (E) is particularly preferred to be a substance that exhibits a significant accelerating effect when used in combination with epoxy curing agents with high room temperature curability, such as aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, and their modifiers.

[0202] Component (E) may be contained only in the first component, only in the second component, or both. From the viewpoint of the storage stability of the cured resin composition, component (E) is preferably contained only in the second component.

[0203] Examples of components (E) include: C1-C12 alkylimidazolium, N-arylimidazolium, 2-methylimidazolium, 2-ethyl-2-methylimidazolium, N-butylimidazolium, and 1-cyanoethyl-2-undecylimidazolium. / Imidazole derivatives such as trimellitate and addition products of epoxy resin and imidazole; tertiary amines such as N,N-dimethylpiperazine, diazabicycloundecene, diazabicyclononene, triethylenediamine, benzyldimethylamine, and triethylamine; phenols such as 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol introduced into a poly(p-vinylphenol) matrix, p-tert-butylphenol, phenol, 4-methoxyphenol, resorcinol, catechol, and 4-tert-butylcatechol; etc. Among these, from the viewpoint of improving curability, phenols are preferred, and diphenols such as resorcinol, catechol, and 4-tert-butylcatechol are more preferred. (E) Components can be used alone or in combination of two or more.

[0204] From the viewpoint of improving curing performance and storage stability, the amount of the epoxy curing accelerator (E) relative to 100 parts by weight of the epoxy resin (A) is preferably 0.1 parts by weight or more and 30 parts by weight or less, more preferably 1 part by weight or more and 20 parts by weight or less, even more preferably 2 parts by weight or more and 15 parts by weight or less, and particularly preferably 3 parts by weight or more and 10 parts by weight or less.

[0205] <Silane Coupling Agent (F)>

[0206] The curable resin composition of the first embodiment may contain a silane coupling agent (F) in the first component and / or the second component described above.

[0207] When the curable resin composition contains component (F), component (F) acts as an adhesive aid to both the surface of the adherend, such as glass and metal, and the curable resin composition.

[0208] Specific examples of silane coupling agents (F) include: isocyanate-containing silanes such as γ-isocyanate propyltrimethoxysilane, γ-isocyanate propyltriethoxysilane, and γ-isocyanate propylmethyldimethoxysilane; amino-containing silanes such as γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-(2-propylethyl)aminopropyltrimethoxysilane, γ-(2-propylethyl)aminopropylmethyldimethoxysilane, γ-(2-propylethyl)aminopropyltriethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; N-(1,3-di-... Ketoimine silanes such as (methylbutylene)-3-(triethoxysilyl)-1-propaneamine; mercapto-containing silanes such as γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropylmethyldimethoxysilane; epoxy-containing silanes such as γ-epoxypropoxypropyltrimethoxysilane, γ-epoxypropoxypropyltriethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane; isocyanurate silanes such as tris(3-trimethoxysilylpropyl)isocyanurate; etc. Among these, epoxy-containing silanes are preferred from the viewpoint of the adhesive strength of the cured product.

[0209] In this specification, the silane coupling agent (F) containing epoxy silanes is sometimes referred to as "epoxy silane coupling agent (F1)".

[0210] Component (F) may be contained only in the first component, only in the second component, or in both the first and second components. From the viewpoint of the storage stability of the curable resin composition, (a) when component (F) is selected from one or more of isocyanate-containing silanes, epoxy-containing silanes (epoxysilane coupling agent (F1)), and isocyanurate silanes, it is preferable that component (F) is contained only in the first component; (b) when component (F) is selected from one or more of amino-containing silanes, ketimine-type silanes, and mercaptosilanes, it is preferable that component (F) is contained only in the second component.

[0211] From the viewpoint of improving adhesion and storage stability, the amount of the silane coupling agent (F) relative to 100 parts by weight of the epoxy resin (A) is preferably 0.1 parts by weight or more and 20 parts by weight or less, more preferably 1 part by weight or more and 15 parts by weight or less, further preferably 2 parts by weight or more and 10 parts by weight or less, and particularly preferably 3 parts by weight or more and 7 parts by weight or less.

[0212] From the perspective of the excellent storage stability of the obtained curable resin composition and the excellent adhesive strength of the cured product formed by curing the curable resin composition, the curable resin composition is more preferably composed of an epoxy silane coupling agent (F1) as component (F).

[0213] <Reinforcer>

[0214] To further improve properties such as toughness, impact resistance, bond strength (shear bond strength), and peel bond strength, the curable resin composition may contain block urethane or unmodified epoxy rubber polymers as reinforcing agents, as needed. Reinforcing agents may be used alone or in combination of two or more.

[0215] <Block carbamate>

[0216] Block urethanes are elastomeric compounds containing urethane and / or urea groups and terminal isocyanate groups, wherein all or part of the terminal isocyanate groups are capped by various capping agents having active hydrogen groups. Particularly preferred are compounds in which all of the terminal isocyanate groups are capped by a capping agent. Such compounds can be obtained, for example, by reacting an excess of a polyisocyanate compound with an organic polymer having terminal active hydrogen groups to produce a polymer (urethane prepolymer) having urethane and / or urea groups in the main chain and terminal isocyanate groups, or simultaneously, by capping all or part of the isocyanate groups with a capping agent having active hydrogen groups.

[0217] As a specific example of a block carbamate, the compound described in International Publication No. 2016 / 163491 can be cited.

[0218] The number-average molecular weight of the block urethane, converted from the molecular weight of polystyrene as determined by GPC, is preferably 2,000 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000. The molecular weight distribution (ratio of weight-average molecular weight to number-average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

[0219] Block carbamates can be used alone or in combination of two or more.

[0220] The amount of block urethane relative to 100 parts by weight of epoxy resin (A) is preferably 1 to 50 parts by weight, more preferably 2 to 40 parts by weight, and particularly preferably 5 to 30 parts by weight. When it is 1 part by weight or more, the improvement effect on toughness, impact resistance, adhesion, etc. is good, and when it is 50 parts by weight or less, the elastic modulus of the cured product is increased.

[0221] <Unmodified epoxy rubber polymers>

[0222] In its unmodified state, without reacting the rubber polymer with the epoxy resin, it can be included (combined) in the curable resin composition as needed.

[0223] Examples of the aforementioned rubber polymers include: acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), hydrogenated nitrile butadiene rubber (HNBR), ethylene propylene rubber (EPDM), acrylic rubber (ACM), butyl rubber (IIR), butadiene rubber, polypropylene oxide, polyethylene oxide, polyepoxybutane, and other polyoxyethylene rubber polymers. These rubber polymers preferably have reactive groups such as amino, hydroxyl, or carboxyl groups at their ends. From the viewpoint of the adhesive properties and impact-peel adhesion of the resulting cured resin composition, NBR and polyoxyethylene are preferred, more preferably NBR, and particularly preferably carboxyl-terminated NBR (CTBN).

[0224] There are no particular limitations on the glass transition temperature (Tg) of the above-mentioned rubber polymers, but it is preferably below -25°C, more preferably below -35°C, even more preferably below -40°C, and particularly preferably below -50°C.

[0225] The number-average molecular weight of the aforementioned rubber polymers, converted from the molecular weight of polystyrene as measured by GPC, is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000. The molecular weight distribution (ratio of weight-average molecular weight to number-average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

[0226] Rubber polymers can be used alone or in combination of two or more.

[0227] The amount of the rubber polymer relative to 100 parts by weight of epoxy resin (A) is preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight, and particularly preferably 5 to 10 parts by weight. When it is 1 part by weight or more, the improvement effect on toughness, impact resistance, adhesion, etc. is good, and when it is 50 parts by weight or less, the elastic modulus of the cured product increases.

[0228] <(C) Inorganic filler materials other than the composition>

[0229] The curable resin composition may contain inorganic fillers other than aluminum hydroxide (C). Examples of inorganic fillers other than component (C) include, for example, silicic acid and / or silicates, such as: dry silica, wet silica, aluminum silicate, magnesium silicate, calcium silicate, wollastonite, talc, etc.

[0230] The aforementioned dry silica, also known as fumed silica, includes, for example, untreated hydrophilic fumed silica and hydrophobic fumed silica produced by chemically treating the silanol group portion of hydrophilic fumed silica with silanes or siloxanes. From the viewpoint of dispersibility in components (A) and (D), hydrophobic fumed silica is preferred. Fumed silica can acquire thixotropy by being added to the first and second components, exhibiting an effect of preventing sagging.

[0231] Other specific examples of inorganic fillers other than component (C) include: reinforcing fillers such as dolomite and carbon black; heavy calcium carbonate, colloidal calcium carbonate, wollastonite, magnesium carbonate, titanium dioxide, iron oxide, aluminum micro powder, zinc oxide, active zinc oxide, etc.

[0232] Inorganic fillers other than component (C) are preferably surface-treated with a surface treatment agent. Surface treatment improves the dispersibility of inorganic fillers other than component (C) in the curable resin composition, resulting in improved physical properties of the cured product.

[0233] (C) Inorganic fillers other than the components can be used alone or in combination of two or more.

[0234] The content (amount) of inorganic filler material other than component (C) is preferably 1 to 100 parts by weight relative to 100 parts by weight of component (A), more preferably 2 to 70 parts by weight, further preferably 5 to 40 parts by weight, and particularly preferably 7 to 20 parts by weight.

[0235] <Monocyclic oxide>

[0236] Curable resin compositions may contain monoepoxides as needed. Monoepoxides can function as reactive diluents. Specific examples of monoepoxides include: aliphatic glycidyl ethers such as butyl glycidyl ether; aromatic glycidyl ethers such as phenyl glycidyl ether and tolyl glycidyl ether; ethers formed from alkyl groups having 8 to 10 carbon atoms and glycidyl groups such as 2-ethylhexyl glycidyl ether; ethers formed from phenyl groups having 6 to 12 carbon atoms that can be replaced by alkyl groups having 2 to 8 carbon atoms and glycidyl groups such as dodecyl glycidyl ether; aliphatic glycidyl esters such as glycidyl (meth)acrylate and glycidyl maleate; glycidyl esters of aliphatic carboxylic acids having 8 to 12 carbon atoms such as tert-butyl glycidyl ester, neodecanoic acid glycidyl ester, and lauric acid glycidyl ester; and glycidyl p-tert-butylbenzoate, etc.

[0237] When using monoepoxides, the content (amount) of monoepoxides in the curable resin composition is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, and particularly preferably 1 to 5 parts by weight relative to 100 parts by weight of component (A). When it is 0.1 parts by weight or more, the viscosity reduction effect is good, and when it is 20 parts by weight or less, the physical properties such as adhesion become good.

[0238] <Other Compounding Ingredients>

[0239] Curing resin compositions may contain other compounding components (additives) as needed. Examples of such compounding components include: free radical curing resins, thermal free radical polymerization initiators, photocuring resins, photopolymerization initiators, azo-type chemical foaming agents, thermally expanding microspheres and other expanding agents, aramid pulps and other fiber pulps, pigments, dyes and other colorants, extender pigments, ultraviolet absorbers, antioxidants, stabilizers (gelling inhibitors), plasticizers, leveling agents, defoamers, antistatic agents, lubricants, viscosity reducers, low-shrinkage agents, organic fillers, thermoplastic resins, desiccants, dispersants, solvents, etc.

[0240] The "content" of each component in a curable resin composition can also be referred to as the "combination amount" of each component.

[0241] <Method for manufacturing curable resin compositions>

[0242] There are no particular limitations on the method for manufacturing the curable resin composition. When the first component of the curable resin composition comprises a composition containing an epoxy resin (A) as the curable resin and core-shell polymer particles as component (B) (hereinafter also referred to as "composition containing polymer particles"), the composition containing polymer particles is preferably a composition in which the core-shell polymer particles (B) are dispersed in the state of primary particles.

[0243] Various methods can be used to obtain a composition (a composition containing polymer particles) in which the core-shell polymer particles (B) are dispersed in the state of primary particles. Examples include: a method in which the core-shell polymer particles (B) obtained in the state of an aqueous latex are contacted with component (A) and then unwanted components such as water are removed; a method in which the core-shell polymer particles (B) are temporarily extracted into an organic solvent, and then the extracted core-shell polymer particles (B) are mixed with component (A) and then the organic solvent is removed. The method described in International Publication No. 2005 / 028546 is preferred. The specific method for manufacturing the composition containing polymer particles preferably includes the following steps in sequence: Step 1, an aqueous latex containing core-shell polymer particles (B) (more specifically, a reaction mixture after manufacturing core-shell polymer particles (B) by emulsion polymerization) is mixed with an organic solvent having a solubility of 5% by weight or more and 40% by weight or less in water at 20°C, and the resulting mixture is further mixed with excess water to cause the core-shell polymer particles (B) to aggregate; Step 2, after separating / recovering the aggregated core-shell polymer particles (B) from the liquid phase, the resulting aggregate of core-shell polymer particles (B) is mixed again with an organic solvent to obtain an organic solvent dispersion of core-shell polymer particles (B); Step 3, after further mixing the organic solvent dispersion with component (A), the aforementioned organic solvent is removed by distillation from the resulting mixture.

[0244] (A) When the component is liquid at 23°C, the third step described above becomes easier, and is therefore preferred. "Liquid at 23°C" means that the softening point is below 23°C and the component exhibits fluidity at 23°C.

[0245] By mixing component (C) and any additional components (A) and other components (such as components (E) and / or (F)) as needed with a composition (a composition containing polymer particles) in which the core-shell polymer particles (B) obtained through the above-described process are dispersed in component (A) in the form of primary particles, a first component of a curable resin composition in which the core-shell polymer particles (B) are dispersed in the form of primary particles can be obtained. Furthermore, by mixing component (D), component (C), and any additional components (such as components (B), (E), and / or (F)) as needed with a mixer such as a planetary mixer, a second component of a curable resin composition can be obtained.

[0246] It should be noted that, in the above description, the method of preparing a curable resin composition by mixing a first component containing core-shell polymer particles (B) with a second component containing or not containing core-shell polymer particles (B) has been described. However, it is also possible to prepare a curable resin composition by mixing a first component that does not contain core-shell polymer particles (B) with a second component containing core-shell polymer particles (B).

[0247] As described above, the first component containing epoxy resin (A) and the second component containing epoxy curing agent (D) are preferably prepared separately. The first and second components are preferably mixed just before use (also referred to as before the bonding operation of the bonded objects or before the curing of the curable resin composition).

[0248] On the other hand, dispersers with high mechanical shear force, such as three-roll mills, roller mills, and kneaders, can be used to redisperse the powdered core-shell polymer particles (B), obtained by solidification and drying through methods such as salting out, into component (A) or component (D). In this case, by applying mechanical shear force at high temperature, the redispersibility of component (B) can be achieved efficiently. The temperature at which component (B) is redispersed into component (A) or component (D) is preferably 50–200°C, more preferably 70–170°C, further preferably 80–150°C, and particularly preferably 90–120°C.

[0249] <Cured product>

[0250] The first and second components of the curable resin composition are uniformly mixed using a static mixer or the like, and the resulting mixture is cured at the curing temperature described later, thereby obtaining a cured product. It can be assumed that the core-shell polymer particles (B) are uniformly dispersed in the first component obtained by the above method, and therefore it can be assumed that the core-shell polymer particles (B) are uniformly dispersed in the cured product obtained using such a first component.

[0251] Furthermore, the cured product formed by curing the curable resin composition is also an embodiment of the present invention (e.g., embodiments 1 to 3). The cured product of one embodiment of the present invention (e.g., embodiments 1 to 3) has the advantage of excellent adhesive strength. The cured product of one embodiment of the present invention (e.g., embodiments 1 to 3) also has the advantage of excellent impact peel resistance and adhesion.

[0252] <Coating Method>

[0253] The curable resin composition can be applied to the substrate by any method. According to a preferred embodiment, the coating can be performed at a low temperature, such as at room temperature, or it can be performed by heating if necessary.

[0254] The first and second components of the curing resin composition can be uniformly mixed and applied simultaneously by a static mixer connected to the front end of the device after being sprayed from the metering spraying device. Alternatively, the first and second components of the curing resin composition can be filled into each barrel of a twin-barrel caulking gun connected to the front end with a static mixer, and then applied by manual extrusion. A coating robot can also be used to extrude the composition onto the substrate in a bead, monofilament, or swirl pattern. It should be noted that the viscosity of the curing resin composition at the coating temperature is not particularly limited, but is preferably around 150–600 Pa·s in the bead extrusion method, around 100 Pa·s in the swirl coating method, and around 20–400 Pa·s in the high-volume coating method using a high-speed flow device.

[0255] <Adhesive>

[0256] Because the cured product exhibits excellent bond strength and impact resistance, it is a preferred material for use as an adhesive. Furthermore, an adhesive comprising a curable resin composition is also an embodiment of the present invention (e.g., embodiments 1 to 3). The adhesive of one embodiment of the present invention (e.g., embodiments 1 to 3) has the advantages of excellent rapid curing and excellent bond strength and impact resistance of the resulting cured product (adhesive layer).

[0257] When using a curable resin composition as an adhesive to bond various substrates together, for example, metals such as aluminum plates and steel plates, wood, plastics, and glass can be joined. Examples of substrates include: steel materials such as cold-rolled steel and galvanized steel, aluminum materials such as aluminum-clad aluminum, general-purpose plastics, engineering plastics, composite materials such as CFRP and GFRP, and various plastic substrates.

[0258] Furthermore, the cured resin composition exhibits excellent thermal conductivity and flame retardancy, making it preferable for use as an adhesive for fixing EV battery cells to the component housing. In other words, the adhesive in one embodiment of the present invention (e.g., embodiments 1 to 3) is preferably an adhesive for secondary batteries. Regarding the manufacturing method of a battery component using an adhesive containing a curable resin composition, and the application method of the adhesive to the coating area of ​​the component, the method described in International Publication No. 2016 / 137303 can be cited as an example.

[0259] The curable resin composition exhibits excellent adhesive properties. Therefore, the curable resin composition is preferably used as an adhesive for bonding (joining) two substrates. The resulting laminate comprises two substrates and an adhesive layer formed by curing the adhesive containing the curable resin composition between the two substrates. Furthermore, this adhesive layer is also an embodiment of the present invention (e.g., embodiments 1 to 3). A laminate of an embodiment of the present invention (e.g., embodiments 1 to 3) can be obtained, for example, by the following method: (1) applying an adhesive containing a curable resin composition to one or two substrates; (2) bringing the substrates into contact with each other in such a way that the adhesive is disposed between the two substrates to be joined; (3) curing the adhesive in this state to join the two substrates. The laminate of an embodiment of the present invention (e.g., embodiments 1 to 3) thus obtained exhibits very high adhesive strength and is therefore preferred.

[0260] The curable resin composition and the adhesive containing the curable resin composition have excellent toughness, and are therefore suitable for bonding dissimilar substrates with different coefficients of linear expansion.

[0261] In addition, curable resin compositions and adhesives containing such curable resin compositions can also be used for bonding structural materials for aerospace applications, particularly external metal structural materials.

[0262] <Curing Temperature>

[0263] The curing temperature of the curable resin composition is not particularly limited, but from the viewpoint of being able to cure easily at around room temperature, it is preferably 5°C to 60°C, more preferably 10°C to 50°C, even more preferably 15°C to 40°C, and particularly preferably 20°C to 30°C.

[0264] <Uses>

[0265] The curable resin composition is preferably used in applications such as adhesives for structural applications in vehicles and aircraft, adhesives for secondary batteries such as EV battery cells, adhesives for structural applications in wind power generation, coatings, materials for lamination with glass fiber and / or carbon fiber to obtain composite materials, materials for printed wiring substrates, solder resists, interlayer insulating films, buildup materials, adhesives for FPCs, electrical insulating materials such as sealing materials for electronic components such as semiconductors / LEDs, chip bonding materials, underlayer fillers, mounting materials for semiconductors (e.g., ACF, ACP, NCF, NCP, etc.), sealing materials for display devices (e.g., LCD panels and OLED displays) and lighting devices (e.g., OLED lighting), and composite materials for concrete repair. The curable resin composition is particularly useful as an adhesive for secondary batteries.

[0266] When using curable resin compositions in composite materials, a wide range of molding methods can be used without particular limitations. Specifically, well-known molding methods such as hand lay-up, spray molding, pultrusion, fiber winding, die molding, prepreg, centrifugal molding, liquid molding, hot pressing, casting, injection molding, continuous lamination, resin transfer molding (RTM), vacuum bag molding, and cold pressing can be used. Curable resin compositions are suitable as raw materials for composites with glass fibers, carbon fibers, BMC (bulk molding compounds), and SMC (sheet molding compounds). In addition, there are no particular restrictions on the application areas. Specifically, it is suitable for use as artificial marble in kitchen cabinets, washbasins, bathtubs, wall materials, resin concrete, water tanks, pressure vessels, industrial pipelines, factory piping, joints, pipes, corrugated plates, helmets, poles, wind turbine blades, oilfield pumping systems such as sucker rods / pumps, motor parts, automobile parts, railway vehicle parts, ship parts, aircraft parts, industrial machinery parts, building materials, furniture, musical instruments, etc., as well as decorative panels and decorative sheets.

[0267] [II. Second Embodiment]

[0268] The second embodiment relates to a two-component curable resin composition comprising epoxy resin, and an adhesive comprising the same.

[0269] Heat-curing single-component curable resin compositions can have their viscosity reduced by increasing the coating temperature. However, two-component curable resin compositions that can cure at low temperatures also require low coating temperatures. A two-component curable resin composition with low viscosity and good workability is desired.

[0270] To improve heat dissipation from electrical equipment, the addition of thermally conductive fillers such as aluminum hydroxide and alumina to the curing resin composition used in the equipment was investigated. However, with the addition of thermally conductive fillers, the viscosity of the curing resin composition increases, sometimes reducing workability. Furthermore, the cured epoxy resins widely used in electrical equipment exhibit low fracture toughness and thus show very brittle properties.

[0271] The resin composition described in Patent Document 1 has insufficient impact resistance, leaving room for improvement. Furthermore, Patent Documents 2 and 3 do not disclose techniques for improving the operability of epoxy-curable resin compositions formed by combining epoxy resin with a large amount of aluminum hydroxide.

[0272] In view of the above situation, the object of the invention of the second embodiment is to provide a two-component curable resin composition that combines epoxy resin and aluminum hydroxide, has low viscosity, good workability, and can produce a cured product exhibiting excellent thermal conductivity, flame retardancy and adhesive strength, and can be cured at low temperatures at or near room temperature.

[0273] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that by combining polymer particles (B) and aluminum hydroxide (C) with a core-shell structure having a specific average particle size and specific composition in a specific weight ratio to a two-component curable resin composition containing a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D), a cured product with low viscosity before curing and exhibiting excellent thermal conductivity, flame retardancy and adhesive strength can be obtained.

[0274] That is, the invention of the second embodiment relates to a curable resin composition, which is a two-component curable resin composition comprising a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D), wherein the curable resin composition further comprises polymer particles (B) having a core-shell structure and aluminum hydroxide (C), wherein the total weight of the aluminum hydroxide (C) is 55% by weight or more and 85% by weight or less relative to the total weight of the curable resin composition, wherein the average particle size of the polymer particles (B) having a core-shell structure is 0.15 μm or more and 0.30 μm or less, wherein the weight ratio of the core layer to the shell layer of the polymer particles (B) having a core-shell structure is 65 / 35 to 92 / 8, wherein the shell layer of the polymer particles (B) having a core-shell structure is a copolymer containing 55 wt% or more of a monomer component comprising an alkyl ester having 1 to 4 carbon atoms of (meth)acrylate, wherein the monomer component constituting the shell layer contains 10 to 100 wt% of an alkyl ester having 1 carbon atom of (meth)acrylate and 0 to 80 wt% of an alkyl ester having 4 carbon atoms of (meth)acrylate.

[0275] The curable resin composition of the present invention, configured as described above, exhibits excellent thermal conductivity, flame retardancy, and adhesive strength in the cured product obtained by using epoxy resin and a high amount of aluminum hydroxide. Furthermore, by using polymer particles with a core-shell structure having a specific average particle size and composition, the viscosity of the curable resin composition can be reduced. That is, according to the second embodiment, a two-component curable resin composition can be provided that exhibits excellent thermal conductivity, flame retardancy, and adhesive strength in the cured product, has low viscosity, good workability, and can be cured at room temperature or near-room temperature.

[0276] In other words, the second embodiment is a curable resin composition containing at least epoxy resin (A), core-shell polymer particles (B), aluminum hydroxide (C), and epoxy curing agent (D). The curable resin composition of the second embodiment is a two-component curable resin composition that includes a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D) as essential components, and further, as needed, mixes other components such as colorant and curing modifier before use. Furthermore, the curable resin composition of the second embodiment further contains core-shell polymer particles (B) and aluminum hydroxide (C). The core-shell polymer particles (B) and aluminum hydroxide (C) are preferably contained in the first component and / or the second component, respectively. In addition to the first and second components, the curable resin composition of the second embodiment may also contain other components as needed.

[0277] According to the curable resin composition of the second embodiment, the cured product obtained by using epoxy resin and a high amount of aluminum hydroxide exhibits excellent thermal conductivity, flame retardancy, and adhesive strength. Furthermore, in the curable resin composition of the second embodiment, the viscosity of the curable resin composition can be reduced by using polymer particles with a core-shell structure having a specific average particle size and specific composition.

[0278] Hereinafter, various methods related to the second embodiment will be described, and except for the matters described in detail below, the description of the first embodiment will be appropriately referenced.

[0279] <Epoxy Resin (A)>

[0280] The various aspects (types, contents, and preferred methods, etc.) of the epoxy resin (A) in the second embodiment are the same as those described in the <Epoxy Resin (A)> section of the first embodiment, therefore, that description is cited here and omitted.

[0281] <Polymer particles with core-shell structure (B)>

[0282] The curable resin composition of the second embodiment contains polymer particles with a core-shell structure as component (B) in the first component and / or the second component described above.

[0283] In the second embodiment, from the viewpoint of industrial productivity and operability of the curable resin composition, the average particle size of the core-shell polymer particles (B) must be 0.15 μm or more and 0.30 μm or less, preferably 0.16 μm or more and 0.28 μm or less, more preferably 0.17 μm or more and 0.27 μm or less, and even more preferably 0.18 μm or more and 0.25 μm or less. In the second embodiment, by setting (a) the average particle size of the core-shell polymer particles (B) to 0.15 μm or more, the viscosity of the curable resin composition is further reduced, thus improving operability; and by setting (b) to 0.30 μm or less, the polymerization time of component (B) is further shortened, further improving industrial productivity.

[0284] In the core-shell polymer particles (B) of the second embodiment, from the perspective of improving the workability of the curable resin composition and improving the impact resistance and adhesion of the cured product, the weight ratio of the core layer to the shell layer (weight of core layer / weight of shell layer) must be 65 / 35 to 92 / 8, preferably 68 / 32 to 91 / 9, and more preferably 70 / 30 to 90 / 10.

[0285] For the core-shell polymer particles (B) of the second embodiment, from the perspective of improving the operability of the curable resin composition, the shell layer must be a copolymer formed by polymerizing 55% or more of an alkyl ester containing 1 to 4 carbon atoms of (meth)acrylic acid in 100% by weight of the monomer component (monomer for shell formation), preferably a copolymer formed by polymerizing a monomer component containing 65% or more by weight, more preferably a copolymer formed by polymerizing a monomer component containing 75% or more by weight, even more preferably a copolymer formed by polymerizing a monomer component containing 78% or more by weight, and particularly preferably a copolymer formed by polymerizing a monomer component containing 83% or more by weight.

[0286] In other words, the shell layer of the second embodiment must contain at least 55% by weight of structural units derived from alkyl esters of (meth)acrylic acid having 1 to 4 carbon atoms in 100% by weight of the shell layer, preferably at least 65% by weight, more preferably at least 75% by weight, further preferably at least 78% by weight, and particularly preferably at least 83% by weight.

[0287] In the second embodiment, the monomer component (shell-forming monomer) constituting the shell of the polymer particle (B) must contain 10% to 100% by weight of an alkyl ester of (meth)acrylic acid with one carbon atom, preferably 11% to 95% by weight, more preferably 12% to 92% by weight, further preferably 13% to 55% by weight, and particularly preferably 14% to 50% by weight. Furthermore, in the second embodiment, the monomer component (shell-forming monomer) constituting the shell layer of the core-shell polymer particle (B) must contain 0% to 80% by weight of an alkyl ester of (meth)acrylic acid with 4 carbon atoms in 100% by weight of the monomer component, preferably 1% to 89% by weight, more preferably 1% to 88% by weight, preferably 1% to 87% by weight, preferably 1% to 86% by weight, more preferably 1% to 78% by weight, more preferably 2% to 76% by weight, more preferably 5% to 76% by weight, more preferably 8% to 76% by weight, more preferably 20% to 74% by weight, more preferably 35% to 72% by weight, further preferably 35% to 60% by weight, and particularly preferably 35% to 50% by weight. When the shell-forming monomer constituting the shell layer of the core-shell polymer particle (B) contains an alkyl ester of (meth)acrylic acid with one carbon atom and / or an alkyl ester of (meth)acrylic acid with four carbon atoms within the range described above, the interaction between the core-shell polymer particle (B) and component (C) can be appropriately controlled. Therefore, the viscosity of the curable resin composition can be controlled at a low level, which has the advantage of improved operability.

[0288] In the second embodiment, the content of aluminum hydroxide (C) in the curable resin composition, as described later, is very high, ranging from 55% to 85% by weight out of 100% of the total weight of the curable resin composition. Therefore, the probability of contact between component (B) and component (C) is high. Thus, in the second embodiment, it is crucial to suppress the viscosity of the curable resin composition to a low level and improve operability by setting the shell polymer of component (B) to a monomer composition that reduces the interaction with the surface of the highly polar component (C). In the second embodiment, the shell of the core-shell polymer particles (B) has the specific configuration described above. The shell of the core-shell polymer particles (B) mixed with epoxy resin is generally configured to improve compatibility with epoxy resin. It can be considered that the specific average particle size and specific composition of component (B) in the second embodiment are specifically designed in an optimized combination with the composition of the second embodiment containing a large amount of aluminum hydroxide (C). The specific average particle size and specific composition of component (B) in the second embodiment are unique features discovered by the inventors in their in-depth research related to the second embodiment.

[0289] From the viewpoint of improving the workability of the curable resin composition, the shell-forming monomer of the second embodiment preferably has both an alkyl ester of (meth)acrylate with one carbon atom and an alkyl ester of (meth)acrylate with four carbon atoms, more preferably containing 13% to 55% by weight of an alkyl ester of (meth)acrylate with one carbon atom and 20% to 74% by weight of an alkyl ester of (meth)acrylate with four carbon atoms. In other words, the shell of the second embodiment preferably has both structural units derived from an alkyl ester of (meth)acrylate with one carbon atom and structural units derived from an alkyl ester of (meth)acrylate with four carbon atoms, more preferably containing 13% to 55% by weight of structural units derived from an alkyl ester of (meth)acrylate with one carbon atom and 20% to 74% by weight of structural units derived from an alkyl ester of (meth)acrylate with four carbon atoms.

[0290] It should be noted that the monomer component of the second embodiment does not need to have a total of 100% by weight of alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms. In other words, for the monomer component of the second embodiment, it is sufficient that the total of monomers other than (a) alkyl esters of (meth)acrylate with one carbon atom, (b) alkyl esters of (meth)acrylate with four carbon atoms, and (c) alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms in 100% of the monomer component is 100% by weight. That is, the monomer component of the second embodiment may contain monomers other than alkyl esters of (meth)acrylate with one carbon atom and alkyl esters of (meth)acrylate with four carbon atoms.

[0291] From the perspective of improving the compatibility and dispersibility of the core-shell polymer particles (B) in the curable resin composition, in the second embodiment, the shell-forming monomer may further include, for example, an aromatic vinyl monomer and / or a vinyl cyanide monomer. By reducing the interaction between component (B) and component (C), the workability of the curable resin composition can be improved. Therefore, in the second embodiment, the content of aromatic vinyl monomer in 100% by weight of the shell-forming monomer is preferably 30% by weight or less, more preferably 20% by weight or less, more preferably 10% by weight or less, more preferably 8% by weight or less, more preferably 6% by weight or less, further preferably 5% by weight or less, and particularly preferably 0% by weight or less (i.e., no aromatic vinyl monomer is contained). Similarly, from the viewpoint of making the workability of the curable resin composition good, in the second embodiment, the content of vinyl cyanide monomer in 100% by weight of the shell-forming monomer is preferably 10% by weight or less, more preferably 8% by weight or less, more preferably 5% by weight or less, more preferably 4% by weight or less, more preferably 3% by weight or less, further preferably 2% by weight or less, even more preferably 1% by weight or less, and particularly preferably 0% by weight or less (i.e., it does not contain vinyl cyanide monomer).

[0292] In the second embodiment, for example, it is preferable to form the shell layer with a copolymer of monomers (total 100% by weight) polymerized to form the shell layer, wherein the shell-forming monomers are (a) 10-100% by weight (preferably 11-95% by weight, particularly 14-50% by weight) of (a) an alkyl ester monomer of (a) meth)acrylic acid with one carbon atom (especially methyl methacrylate), (b) 0-80% by weight (preferably 1-78% by weight, particularly 35-72% by weight) of (b) an alkyl ester monomer of (a) meth)acrylic acid with four carbon atom (especially butyl acrylate), and (c) less than 30% by weight (preferably 20% by weight). The product comprises (d) 10% by weight or less of vinyl cyanide monomer (especially acrylonitrile) (preferably 8% by weight or less, more preferably 5% by weight or less, more preferably 4% by weight or less, more preferably 3% by weight or less, more preferably 2% by weight or less, more preferably 1% by weight or less, and especially preferably 0% by weight), and (e) 0 to 45% by weight of epoxy-containing monomer (especially glycidyl methacrylate) (preferably 0 to 25% by weight, more preferably 3 to 20% by weight). This allows for a balanced and effective improvement in both toughness and workability.

[0293] <Aluminum hydroxide (C)>

[0294] The curable resin composition of the second embodiment contains aluminum hydroxide as component (C) in the first component and / or the second component described above. When the curable resin composition of the second embodiment contains component (C), the resulting cured product has the advantages of excellent thermal conductivity and flame retardancy (e.g., flame retardancy evaluated by vertical burning test (UL94)).

[0295] In the second embodiment, the total weight of aluminum hydroxide (C) must be more than 55% by weight and less than 85% by weight relative to the total weight of the curable resin composition.

[0296] In the second embodiment, the average particle size of component (C) is not particularly limited. In the second embodiment, from the viewpoint of balancing the impact resistance and adhesive strength of the obtained cured product, and from the viewpoint of suppressing the sedimentation of component (E) in the curable resin composition before curing, the average particle size of component (C) is preferably 11 μm or more and 200 μm or less, more preferably 12 μm or more and 150 μm or less, further preferably 13 μm or more and 100 μm or less, further more preferably 15 μm or more and 50 μm or less, and particularly preferably 17 μm or more and 30 μm or less.

[0297] In the second embodiment, from the viewpoint of improving the properties of the obtained cured product (thermal conductivity, flame retardancy, adhesive strength, and impact resistance) and the viewpoint of improving the workability of the composition before curing, the total weight of aluminum hydroxide (C) relative to the total weight of the curable resin composition must be 55% by weight or more and 85% by weight or less, preferably 57% by weight or more and 80% by weight or less, more preferably 60% by weight or more and 76% by weight or less, further preferably 62% by weight or more and 73% by weight or less, and particularly preferably 65% ​​by weight or more and 70% by weight or less.

[0298] Regarding the aluminum hydroxide (C) of the second embodiment, for methods other than those described above, the description of the first embodiment shall be appropriately referenced.

[0299] The curable resin composition of the second embodiment may contain thermally conductive fillers other than aluminum hydroxide (other than component (C)) and / or flame retardants other than aluminum hydroxide (other than component (C)). Regarding the various methods (types, contents, and preferred methods, etc.) of "thermally conductive fillers other than aluminum hydroxide" and "flame retardants other than aluminum hydroxide" in the second embodiment, the descriptions are the same as those in the section on "thermally conductive fillers other than aluminum hydroxide" and "flame retardants other than aluminum hydroxide" in the first embodiment; therefore, that description is cited here and omitted.

[0300] <Epoxy Curing Agent (D)>

[0301] The curable resin composition of the second embodiment contains an epoxy curing agent as component (D) in the second component. Regarding the various aspects (types, contents, and preferred embodiments, etc.) of the "epoxy curing agent (D)" in the second embodiment, the description is the same as that in the item "epoxy curing agent (D)" of the first embodiment, therefore, that description is cited here and omitted.

[0302] <(D) Epoxy curing agents that exhibit activity at high temperatures>

[0303] Within a range that does not impair the curing speed of the curable resin composition of the second embodiment, epoxy curing agents that exhibit activity at high temperatures, other than epoxy curing agents containing active hydrogen groups capable of reacting with epoxy resin at low temperatures (such as the aforementioned amine curing agents and thiol curing agents), may be included. Regarding the various aspects (types, contents, and preferred embodiments, etc.) of "epoxy curing agents other than component (D) that exhibit activity at high temperatures" in the second embodiment, the description is the same as that in the item "<epoxy curing agents other than component (D) that exhibit activity at high temperatures>" in the first embodiment; therefore, that description is cited here and omitted.

[0304] <Epoxy Curing Accelerator (E)>

[0305] The curable resin composition of the second embodiment may contain an epoxy curing accelerator (E) in the first component and / or the second component described above. Regarding the various methods (types, contents, and preferred methods, etc.) of the "epoxy curing accelerator (E)" in the second embodiment, the description is the same as that in the item "epoxy curing accelerator (E)" of the first embodiment, therefore, that description is cited here and omitted.

[0306] <Silane Coupling Agent (F)>

[0307] The curable resin composition of the second embodiment may contain a silane coupling agent (F) in the first component and / or the second component described above. Regarding the various methods (types, contents, and preferred methods, etc.) of the "silane coupling agent (F)" in the second embodiment, the description is the same as that in the <Silane Coupling Agent (F)> section of the first embodiment, therefore, that description is cited here and omitted.

[0308] [III. Third Embodiment]

[0309] The third embodiment relates to curable resin compositions, cured products, adhesives, and laminates.

[0310] Two-component epoxy resin compositions using aliphatic amine curing agents are cured at low temperatures. Therefore, two-component epoxy resin compositions do not require heating equipment for curing. Due to their superior strength, heat resistance, water resistance, chemical resistance, and electrical insulation, cured products obtained from two-component epoxy resin compositions have been widely used in industrial and civil engineering applications. Currently, various compositions have been developed as two-component epoxy resin compositions (e.g., Patent Document 4, etc.).

[0311] As mentioned above, although the cured product obtained by curing a two-component epoxy resin composition has excellent strength, there is a tendency for two-component epoxy resin compositions to have a slow curing speed.

[0312] Especially in sectors like automotive, where productivity (production cycle time) is critical, the rapid curing properties of two-component adhesives are essential. Furthermore, rapid curing is also required for two-component adhesives used to secure batteries in electric vehicles (EVs).

[0313] However, from the viewpoint of rapid solidification, the aforementioned prior art (such as the technology described in Patent Document 4) is not sufficient and there is still room for further improvement.

[0314] The third embodiment was made in view of the above-mentioned problems, and its purpose is to provide a new curable resin composition of two-component or multi-component type with excellent rapid curing properties.

[0315] In order to solve the above-mentioned problems, the inventors conducted in-depth research and as a result, completed the invention of the third embodiment.

[0316] In order to solve the above-mentioned problems, the inventors conducted in-depth research and independently discovered the following new insights, thereby completing the present invention in the third embodiment: by combining a compound having one aromatic ring and at least two phenolic hydroxyl groups in one molecule, and having 0 or 1 tertiary alkyl groups located at the adjacent positions of the phenolic hydroxyl groups in one molecule, it is possible to obtain a two-component or multi-component curable resin composition with excellent rapid curing properties.

[0317] The curable resin composition of the third embodiment is a two-component or multi-component curable resin composition comprising a first component containing epoxy resin (A) and a second component containing epoxy curing agent (D), wherein the curable resin composition further comprises polymer particles (B) and compound (G), the polymer particles (B) having a core-shell structure comprising a core layer and a shell layer, the compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, wherein the number of tertiary alkyl groups located adjacent to the phenolic hydroxyl groups in the compound (G) is 0 or 1 in one molecule, and the epoxy curing agent (D) is selected from at least one of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0318] Sometimes the "curable resin composition of the third embodiment" is referred to as the "third curable resin composition".

[0319] According to the third embodiment, it has the effect of providing a two-component or multi-component curable resin composition with excellent rapid curing properties.

[0320] Hereinafter, various methods related to the third embodiment will be described, and except for the matters described in detail below, the descriptions of the first and second embodiments will be appropriately referenced.

[0321] The third curable resin composition, having the above-described structure, has the advantage of exhibiting excellent rapid curing properties. It should be noted that, in this specification, "rapid curing property" refers to the property of curing at around room temperature (e.g., 5°C to 50°C) for a short time (e.g., several minutes to several hours). That is, the third curable resin composition has the advantage of curing at temperatures below 5°C for a short time (e.g., several minutes to several hours) at temperatures below 5°C without requiring heat treatment at temperatures exceeding 50°C.

[0322] The third-curing resin composition contains epoxy resin (A) in the first component; in other words, it can also be called a two-component epoxy resin composition or a multi-component epoxy resin composition. Therefore, the third-curing resin composition also has the advantage of excellent adhesive strength.

[0323] As two-component adhesives, besides two-component epoxy resin compositions, two-component urethane compositions with urethane resin as the main component are also known. Compared to two-component epoxy resin compositions, two-component urethane compositions have rapid curing properties, enabling them to cure in a short time. However, compared to two-component epoxy resin compositions, two-component urethane compositions tend to have shortcomings in the strength and heat resistance of the resulting cured product.

[0324] For two-component adhesives used to secure batteries in electric vehicles (EVs), a balance between rapid curing and strength is often required.

[0325] As described above, the third-curing resin composition exhibits excellent adhesive strength and rapid curing properties. Therefore, the third-curing resin composition is particularly preferred for use as a two-component adhesive for securing batteries in electric vehicles (EVs).

[0326] In addition, the third curing resin composition contains polymer particles (B) having a core-shell structure containing a core layer and a shell layer. Therefore, the third curing resin composition also has the advantage of excellent impact-resistant peel adhesion.

[0327] <Epoxy Resin (A)>

[0328] Regarding the various aspects of epoxy resin (A) in the third embodiment (types, contents, and preferred methods thereof), the description is the same as that in the item <Epoxy Resin (A)> of the first embodiment, therefore, that description is cited and omitted here.

[0329] <Polymer particles with core-shell structure (B)>

[0330] The curable resin composition of the third embodiment contains polymer particles with a core-shell structure as component (B) in the first component and / or the second component described above. Regarding the various configurations of the polymer particles (B) with a core-shell structure in the third embodiment (e.g., the composition of the core layer, the composition of the shell layer, and their preferred configurations, etc.), the description is the same as that in the item "Polymer particles (B) with a core-shell structure" in the first embodiment, and therefore, that description is cited here and omitted.

[0331] <Compound (G)>

[0332] The curable resin composition of the third embodiment contains, in the first component and / or the second component described above, a compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups per molecule as component (G). In this compound (G), the number of tertiary alkyl groups located ortho to the phenolic hydroxyl groups is 0 or 1 per molecule.

[0333] Compound (G), by combining with polymer particles (B) and the epoxy curing agent (D) described later, has the effect of increasing the curing speed of the curable resin composition while maintaining good adhesive strength. Furthermore, the curable resin composition of the third embodiment, by including compound (G) together with the polymer particles (B) and the epoxy curing agent (D) described later, does not require heat treatment at temperatures exceeding 50°C, exhibiting excellent rapid curing properties and curing in a shorter time compared to curable resin compositions without compound (G).

[0334] Component (G) may be contained only in the first component, only in the second component, or both. From the viewpoint of the storage stability of the cured resin composition, component (G) is preferably contained only in the second component.

[0335] In this specification, aromatic rings refer to cyclic hydrocarbons and heterocyclic compounds that satisfy Hückel's rule. Specific examples of aromatic rings include: benzene, naphthalene, azurite, anthracene, pyrrole, pyridine, furan, thiophene, etc. From the viewpoint of improving rapid curing performance and ease of acquisition, benzene is particularly preferred.

[0336] In this specification, a phenolic hydroxyl group refers to a hydroxyl group bonded to a carbon atom of an aromatic ring. In compound (G), the positions of the two phenolic hydroxyl groups are not particularly limited and can be located on any carbon atom of the aromatic ring.

[0337] When the aromatic ring is benzene, the two phenolic hydroxyl groups can be in any positional relationship, such as ortho, meta, or para. From the perspective of improving the effect of excellent rapid curing, an ortho or meta positional relationship is more preferred, and a meta positional relationship is even more preferred.

[0338] Without impairing the effects of one embodiment of the present invention, in addition to the two phenolic hydroxyl groups, compound (G) may also have at least one further substituent on the aromatic ring. Further substituents are not particularly limited, but examples include alkyl groups with 8 or fewer carbon atoms (methyl, ethyl, propyl, 1-methylethyl (isopropyl), butyl, 1,1-dimethylethyl (tert-butyl) etc.), halogens (chlorine, bromine, iodine), etc.

[0339] In the case where compound (G) has a tertiary alkyl group (e.g., tert-butyl group) as a further substituent, the number of tertiary alkyl groups located ortho to the phenolic hydroxyl group in one molecule is 0 or 1. When there are two or more tertiary alkyl groups located ortho to the phenolic hydroxyl group in one molecule of compound (G), the effect of improving rapid curing properties cannot be obtained, and the curing time increases, which is therefore undesirable. The reason for this is not determined, but it can be speculated that it is because the steric hindrance of the tertiary alkyl group hinders the improvement of rapid curing properties.

[0340] Compound (G) preferably does not have any substituents other than the two phenolic hydroxyl groups on the aromatic ring. This configuration offers the advantage of improved rapid curing and enhanced curing performance.

[0341] Examples of compounds (G) include: 1,3-dihydroxybenzene (also known as resorcinol), 1,2-dihydroxybenzene (also known as catechol), 1,4-dihydroxybenzene (also known as hydroquinone), 4-tert-butylcatechol, methyl hydroquinone, tert-butyl hydroquinone, chlorohydroquinone, 2,5-dichlorohydroquinone, 2,5-dibromohydroquinone, pyrogallol, hydroxyquinoline, and pyrogallol. From the perspective of improving the effect of excellent rapid curing properties, resorcinol, catechol, hydroquinone, and methyl hydroquinone are more preferred, resorcinol and catechol are even more preferred, and resorcinol is particularly preferred.

[0342] Compound (G) can be used alone or in combination of two or more.

[0343] The curable resin composition of the third embodiment contains 1 to 25 parts by weight of compound (G) relative to 100 parts by weight of epoxy resin (A), more preferably 2 to 20 parts by weight, even more preferably 3 to 15 parts by weight, and particularly preferably 4 to 10 parts by weight. When the content of compound (G) is 1 part by weight or more relative to 100 parts by weight of epoxy resin (A) (a), the effect of compound (G) in improving rapid curing is well exerted; when it is 25 parts by weight or less (b), the curable resin composition has the advantages of good storage stability and ease of handling.

[0344] It should be noted that bisphenol A and 2,4,6-tris(dimethylaminomethyl)phenol, among other compounds having phenolic hydroxyl groups, are known as curing aids to accelerate the curing speed of the epoxy curing agent (D) described later. The use of compounds such as bisphenol A, which have two aromatic rings and two phenolic hydroxyl groups per molecule, is restricted due to environmental regulations, making them difficult to handle. Therefore, in the curable resin composition of the third embodiment, a lower content of the compound having two aromatic rings and two phenolic hydroxyl groups per molecule (bisphenol A) is preferred; for example, 3 parts by weight or less relative to 100 parts by weight of epoxy resin (A) is preferred. However, without impairing the effects of one embodiment of the present invention, the curable resin composition of the third embodiment may include a compound having two aromatic rings and two phenolic hydroxyl groups per molecule (e.g., bisphenol A).

[0345] In the curable resin composition of the third embodiment, the content of a compound (bisphenol A) having two aromatic rings and two phenolic hydroxyl groups in one molecule may be less than 2 parts by weight, less than 1 part by weight, less than 0.5 parts by weight, or less than 0.1 parts by weight relative to 100 parts by weight of epoxy resin (A).

[0346] Furthermore, in the third embodiment, the inventors independently discovered that using a compound having one phenolic hydroxyl group per molecule, such as 2,4,6-tris(dimethylaminomethyl)phenol, as a curing agent instead of the epoxy curing agent (D) described later resulted in insufficient improvement in rapid curing properties. However, without impairing the effects of one embodiment of the invention, the curable resin composition of the third embodiment may contain a compound having one phenolic hydroxyl group per molecule (e.g., 2,4,6-tris(dimethylaminomethyl)phenol).

[0347] <Aluminum hydroxide (C)>

[0348] The curable resin composition of the third embodiment may further contain aluminum hydroxide (C), or may not contain it. Preferably, the curable resin composition of the third embodiment contains aluminum hydroxide (C) in the first component and / or the second component described above. When the curable resin composition of the third embodiment contains component (C), the resulting cured product has the advantages of excellent thermal conductivity and flame retardancy (e.g., flame retardancy evaluated by the vertical burning test (UL94)).

[0349] In the third embodiment, the average particle size of component (C) is not particularly limited. In the third embodiment, from the viewpoint of balancing the impact resistance and adhesive strength of the obtained cured product, and from the viewpoint of suppressing the sedimentation of component (C) in the curable resin composition before curing, the average particle size of component (C) is preferably 11 μm or more and 200 μm or less, more preferably 12 μm or more and 150 μm or less, even more preferably 13 μm or more and 100 μm or less, even more preferably 15 μm or more and 50 μm or less, and particularly preferably 17 μm or more and 30 μm or less.

[0350] In the third embodiment, the total weight of aluminum hydroxide (C) is not particularly limited relative to the total weight of the curable resin composition. In the third embodiment, from the viewpoint of improving the properties of the obtained cured product (thermal conductivity, flame retardancy, bond strength, and impact resistance) and improving the workability of the composition before curing, the total weight of aluminum hydroxide (C) relative to the total weight of the curable resin composition is preferably 55% by weight or more and 85% by weight or less, more preferably 57% by weight or more and 80% by weight or less, more preferably 60% by weight or more and 76% by weight or less, further preferably 62% by weight or more and 73% by weight or less, and particularly preferably 65% ​​by weight or more and 70% by weight or less.

[0351] Regarding the aluminum hydroxide (C) of the third embodiment, for methods other than those described above, the description of the first embodiment shall be appropriately referenced.

[0352] The curable resin composition of the third embodiment may contain thermally conductive fillers other than aluminum hydroxide (other than component (C)) and / or flame retardants other than aluminum hydroxide (other than component (C)). Regarding the various methods (types, contents, and preferred methods, etc.) of "thermally conductive fillers other than aluminum hydroxide" and "flame retardants other than aluminum hydroxide" in the third embodiment, the descriptions are the same as those in the section on "thermally conductive fillers other than aluminum hydroxide" and "flame retardants other than aluminum hydroxide" in the first embodiment; therefore, that description is cited here and omitted.

[0353] <Epoxy Curing Agent (D)>

[0354] The curable resin composition of the third embodiment contains an epoxy curing agent as component (D) in the second component. In the third embodiment, an amine curing agent is preferably used as the epoxy curing agent (D).

[0355] In the third embodiment, the amine curing agent is selected from at least one of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber. In the third embodiment, the epoxy curing agent (D) can be selected from at least one of the group consisting of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber, or it can be composed of only at least one of the group. When the epoxy curing agent (D) is selected from at least one of the above-mentioned group, or is composed of only one of the group, the curable resin composition has the advantage of excellent curing properties at room temperature (rapid curing properties). In the third embodiment, the epoxy curing agent (D) can be used alone or in combination of two or more.

[0356] Regarding the epoxy curing agent (D) of the third embodiment, among the amine curing agents, (a) from the viewpoint of the impact resistance of the obtained cured product, (a-1) it is preferable to include one or more selected from terminal amino polyethers and terminal aminobutyronitrile rubber, (a-2) more preferably one or more selected from terminal amino polyethers and terminal aminobutyronitrile rubber, (b) further from the viewpoint of curability, it is more preferable to include terminal aminobutyronitrile rubber, and even more preferably terminal aminobutyronitrile rubber. Regarding the epoxy curing agent (D) of the third embodiment, among the amine curing agents, (a) from the viewpoint of the adhesive strength of the obtained cured product, (a-1) it is preferable to include one or more selected from alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber; (a-2) it is more preferable to include one or more selected from alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber; (b) further from the viewpoint of curability, (b-1) it is more preferable to include one or more selected from alicyclic amines and amino-terminated nitrile rubber; (b-2) it is more preferable to include one or more selected from alicyclic amines and amino-terminated nitrile rubber. From the viewpoint of the adhesive strength and curing properties of the obtained cured product, the epoxy curing agent (D) of the third embodiment more preferably includes at least one selected from alicyclic amines, terminating aminobutadiene nitrile rubber, modified alicyclic amines and modified terminating aminobutadiene nitrile rubber, and even more preferably at least one selected from alicyclic amines, terminating aminobutadiene nitrile rubber, modified alicyclic amines and modified terminating aminobutadiene nitrile rubber.

[0357] Regarding the epoxy curing agent (D) of the third embodiment, for methods other than those described above, the description of the first embodiment shall be appropriately referenced.

[0358] <(D) Epoxy curing agents that exhibit activity at high temperatures>

[0359] Within a range that does not impair the curing speed of the curable resin composition of the third embodiment, epoxy curing agents that exhibit activity at high temperatures may be included, except for epoxy curing agents containing active hydrogen groups capable of reacting with epoxy resin at low temperatures (such as the aforementioned amine curing agents, thiol curing agents, etc.). Regarding the various aspects (types, contents, and preferred embodiments, etc.) of "epoxy curing agents other than component (D) that exhibit activity at high temperatures" in the third embodiment, the description is the same as that in the item "<epoxy curing agents other than component (D) that exhibit activity at high temperatures>" in the first embodiment, therefore, that description is cited and omitted here.

[0360] <Epoxy curing accelerators (H) other than compound (G)>

[0361] The first component and / or the second component of the curable resin composition of the third embodiment may contain an epoxy curing accelerator (H) other than compound (G) (hereinafter sometimes referred to as "(H) component").

[0362] Component (H) is a compound that does not readily react with epoxy resin (A) to form crosslinks, but it can accelerate the curing reaction based on epoxy resin (A) and epoxy curing agent (D). Component (H) is particularly preferred as a substance that exhibits a significant curing acceleration effect when used in combination with the aforementioned component (D), i.e., an epoxy curing agent with high curability at room temperature.

[0363] Component (H) may be contained only in the first component, only in the second component, or both. From the viewpoint of the storage stability of the cured resin composition, component (H) is preferably contained only in the second component.

[0364] Examples of (H) components include: alkylimidazolium, N-arylimidazolium, 2-methylimidazolium, 2-ethyl-2-methylimidazolium, N-butylimidazolium, and 1-cyanoethyl-2-undecylimidazolium, which have 1 to 12 carbon atoms (C1-C12). The following are examples of imidazole derivatives: trimellitate, addition products of epoxy resin and imidazole, etc.; tertiary amines: N,N-dimethylpiperazine, diazabicycloundecene, diazabicyclononene, triethylenediamine, benzyldimethylamine, triethylamine, etc.; phenols: 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol introduced into a poly(p-vinylphenol) matrix, p-tert-butylphenol, phenol, 4-methoxyphenol, etc. From the viewpoint of improving curability, imidazole derivatives and phenols are preferred, and phenols such as 2,4,6-tris(dimethylaminomethyl)phenol are more preferred. Component (H) can be used alone or in combination of two or more.

[0365] From the viewpoint of balancing the improvement of curing properties and storage stability, the content of the epoxy curing accelerator (H) in the curable resin composition of the third embodiment relative to 100 parts by weight of the epoxy resin (A) is preferably 0.1 parts by weight or more and 30 parts by weight or less, more preferably 1 part by weight or more and 20 parts by weight or less, further preferably 2 parts by weight or more and 15 parts by weight or less, and particularly preferably 3 parts by weight or more and 10 parts by weight or less.

[0366] One embodiment of the present invention may have the following configuration.

[0367] [A1] A curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), which is a two-component curable resin composition.

[0368] The curable resin composition further contains polymer particles (B) having a core-shell structure and aluminum hydroxide (C), wherein the total weight of the aluminum hydroxide (C) is 55% by weight or more and 85% by weight or less relative to the total weight of the curable resin composition, and the average particle size of the aluminum hydroxide (C) is 11 μm or more and 200 μm or less.

[0369] [A2] The curable resin composition according to [A1], wherein the polymer particles (B) having a core-shell structure and the aluminum hydroxide (C) are respectively contained in the first component and / or the second component.

[0370] [A3] The curable resin composition according to [A1] or [A2], wherein the ratio of the number of moles of epoxy groups in the epoxy resin (A) to the number of moles of active hydrogen groups in the epoxy curing agent (D) is 0.5 or more and 1.5 or less.

[0371] [A4] The curable resin composition according to any one of [A1] to [A3], wherein the epoxy resin (A) is a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin.

[0372] [A5] The curable resin composition according to any one of [A1] to [A4], wherein the epoxy curing agent (D) is one or more amine curing agents selected from aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, and amino-terminated nitrile rubber, or a modified thereof.

[0373] [A6] The curable resin composition according to any one of [A1] to [A5], wherein the amount of the core-shell polymer particles (B) relative to 100 parts by weight of the epoxy resin (A) is 1 part by weight or more and 100 parts by weight or less.

[0374] [A7] The curable resin composition according to any one of [A1] to [A6], wherein the amount of aluminum hydroxide (C) in the formulation relative to 100 parts by weight of the epoxy resin (A) is 250 parts by weight or more and 750 parts by weight or less.

[0375] [A8] The curable resin composition according to any one of [A1] to [A7], wherein the amount of the epoxy curing agent (D) relative to 100 parts by weight of the epoxy resin (A) is 15 parts by weight or more and 300 parts by weight or less.

[0376] [A9] The curable resin composition according to any one of [A1] to [A8] further contains an epoxy curing accelerator (E) in the first component and / or the second component.

[0377] [A10] The curable resin composition according to any one of [A1] to [A9] further contains a silane coupling agent (F) in the first component and / or the second component.

[0378] [A11] The curable resin composition according to any one of [A1] to [A10], wherein the polymer particles (B) having the core-shell structure have one or more core layers selected from diene rubbers, (meth)acrylate rubbers, and organosiloxane rubbers.

[0379] [A12] According to the curable resin composition of [A11], wherein the polymer particles (B) having a core-shell structure have a diene rubber, wherein the diene rubber is butadiene rubber and / or styrene-butadiene rubber.

[0380] [A13] The curable resin composition according to any one of [A1] to [A12], wherein the polymer particles (B) having the core-shell structure have a shell layer formed by grafting and polymerizing one or more monomer components selected from aromatic vinyl monomers, vinyl cyanide monomers and (meth)acrylate monomers onto the core layer.

[0381] [A14] The curable resin composition according to any one of [A1] to [A13], wherein the polymer particles (B) having a core-shell structure have epoxy groups in the shell layer.

[0382] [A15] The curable resin composition according to any one of [A1] to [A14], wherein the polymer particles (B) having the core-shell structure have a shell formed by grafting and polymerizing an epoxy-based monomer component onto the core layer.

[0383] [A16] The curable resin composition according to any one of [A1] to [A15], wherein the polymer particles (B) having a core-shell structure have epoxy groups in the shell layer, and the content of the epoxy groups in the shell layer is 0.1 to 2.0 mmol / g or less relative to the total amount of the shell layer.

[0384] [A17] The curable resin composition according to any one of [A1] to [A13], wherein the polymer particles (B) having the core-shell structure do not contain epoxy groups in the shell layer.

[0385] [A18] A cured product, which is formed by curing the curable resin composition described in any one of [A1] to [A17].

[0386] [A19] An adhesive comprising any one of the curable resin compositions described in [A1] to [A17].

[0387] [A20] The adhesive according to [A19], wherein the adhesive is an adhesive for secondary batteries.

[0388] [A21] A laminate comprising:

[0389] 2 substrates, and

[0390] An adhesive layer formed by curing the adhesive described in [A19] or [A20] that bonds the two substrates.

[0391] One embodiment of the present invention may have the following configuration.

[0392] [B1] A curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), wherein the curable resin composition further comprises polymer particles (B) having a core-shell structure and aluminum hydroxide (C), wherein the total weight of the aluminum hydroxide (C) is 55% by weight or more and 85% by weight or less relative to the total weight of the curable resin composition, the average particle size of the polymer particles (B) having a core-shell structure is 0.15 μm or more and 0.30 μm or less, the weight ratio of the core layer to the shell layer of the polymer particles (B) having a core-shell structure is 65 / 35 to 92 / 8, and the polymer particles (B) having a core-shell structure are copolymers in which the shell layer contains 55 wt% or more of a monomer component of an alkyl ester having 1 to 4 carbon atoms of (meth)acrylic acid, and the monomer component constituting the shell layer contains 10 to 100 wt% of an alkyl ester having 1 carbon atom of (meth)acrylic acid and 0 to 80 wt% of an alkyl ester having 4 carbon atoms of (meth)acrylic acid.

[0393] [B2] The curable resin composition according to [B1], wherein the polymer particles (B) having a core-shell structure and the aluminum hydroxide (C) are respectively contained in the first component and / or the second component.

[0394] [B3] The curable resin composition according to [B1] or [B2], wherein the ratio of the number of moles of epoxy groups in the epoxy resin (A) to the number of moles of active hydrogen groups in the epoxy curing agent (D) is 0.5 or more and 1.5 or less.

[0395] [B4] The curable resin composition according to any one of [B1] to [B3], wherein the epoxy resin (A) is a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin.

[0396] [B5] The curable resin composition according to any one of [B1] to [B4], wherein the epoxy curing agent (D) is one or more amine curing agents selected from aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, and amino-terminated nitrile rubber, or a modified thereof.

[0397] [B6] The curable resin composition according to any one of [B1] to [B5], wherein the amount of the core-shell polymer particles (B) relative to 100 parts by weight of the epoxy resin (A) is 1 part by weight or more and 100 parts by weight or less.

[0398] [B7] The curable resin composition according to any one of [B1] to [B6], wherein the amount of aluminum hydroxide (C) in the formulation relative to 100 parts by weight of the epoxy resin (A) is 250 parts by weight or more and 750 parts by weight or less.

[0399] [B8] The curable resin composition according to any one of [B1] to [B7], wherein the amount of the epoxy curing agent (D) relative to 100 parts by weight of the epoxy resin (A) is 15 parts by weight or more and 300 parts by weight or less.

[0400] [B9] The curable resin composition according to any one of [B1] to [B8] further contains an epoxy curing accelerator (E) in the first component and / or the second component.

[0401] [B10] The curable resin composition according to any one of [B1] to [B9] further contains a silane coupling agent (F) in the first component and / or the second component.

[0402] [B11] The curable resin composition according to any one of [B1] to [B10], wherein the polymer particles (B) having the core-shell structure have one or more core layers selected from diene rubbers, (meth)acrylate rubbers, and organosiloxane rubbers.

[0403] [B12] The curable resin composition according to [B11], wherein the polymer particles (B) having a core-shell structure have a diene rubber, wherein the diene rubber is butadiene rubber and / or styrene-butadiene rubber.

[0404] [B13] The curable resin composition according to any one of [B1] to [B12], wherein the polymer particles (B) having the core-shell structure have a shell layer formed by grafting and polymerizing one or more monomer components selected from aromatic vinyl monomers, vinyl cyanide monomers and (meth)acrylate monomers onto the core layer.

[0405] [B14] A curable resin composition according to any one of [B1] to [B13], wherein the polymer particles (B) having a core-shell structure have epoxy groups in the shell layer.

[0406] [B15] The curable resin composition according to any one of [B1] to [B14], wherein the polymer particles (B) having the core-shell structure have a shell formed by grafting and polymerizing an epoxy-based monomer component onto the core layer.

[0407] [B16] The curable resin composition according to any one of [B1] to [B15], wherein the polymer particles (B) having a core-shell structure have epoxy groups in the shell layer, and the content of the epoxy groups in the shell layer is 0.1 to 2.0 mmol / g or less relative to the total amount of the shell layer.

[0408] [B17] A curable resin composition according to any one of [B1] to [B13], wherein the polymer particles (B) having a core-shell structure do not contain epoxy groups in the shell layer.

[0409] [B18] A cured product formed by curing the curable resin composition described in any one of [B1] to [B17].

[0410] [B19] An adhesive comprising any one of the curable resin compositions described in [B1] to [B17].

[0411] [B20] The adhesive according to [B19], wherein the adhesive is an adhesive for secondary batteries.

[0412] [B21] A laminate comprising:

[0413] 2 substrates, and

[0414] An adhesive layer formed by curing the adhesive described in [B19] or [B20] that bonds the two substrates.

[0415] One embodiment of the present invention may have the following configuration.

[0416] [C1] A curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), wherein the curable resin composition further comprises polymer particles (B) and a compound (G), the polymer particles (B) having a core-shell structure comprising a core layer and a shell layer, the compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, wherein the number of tertiary alkyl groups located adjacent to the phenolic hydroxyl groups in the compound (G) is 0 or 1 in one molecule, and the epoxy curing agent (D) is selected from at least one of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0417] [C2] According to the curable resin composition of [C1], the ratio of the number of moles of epoxy groups in the epoxy resin (A) to the number of moles of active hydrogen groups in the epoxy curing agent (D) (the number of moles of epoxy groups / the number of moles of active hydrogen groups) is 0.5 or more and 1.6 or less.

[0418] [C3] The curable resin composition according to [C1] or [C2], wherein the epoxy resin (A) is a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin.

[0419] [C4] The curable resin composition according to any one of [C1] to [C3], wherein the epoxy curing agent (D) is selected from at least one of alicyclic amines, aminobutadiene nitrile rubber, modified alicyclic amines and modified aminobutadiene nitrile rubber.

[0420] [C5] The curable resin composition according to any one of [C1] to [C4], wherein the content of the polymer particles (B) relative to 100 parts by weight of the epoxy resin (A) is 1 part by weight or more and 100 parts by weight or less.

[0421] [C6] The curable resin composition according to any one of [C1] to [C5] further contains aluminum hydroxide (C) in the first component and / or the second component.

[0422] [C7] The curable resin composition according to any one of [C1] to [C6], wherein the content of the epoxy curing agent (D) in the curable resin composition is 15 parts by weight or more and 300 parts by weight or less relative to 100 parts by weight of the epoxy resin (A).

[0423] [C8] The curable resin composition according to [C6], wherein the content of aluminum hydroxide (C) in the curable resin composition is 250 parts by weight or more and 750 parts by weight or less relative to 100 parts by weight of epoxy resin (A).

[0424] [C9] The curable resin composition according to any one of [C1] to [C8] further contains a silane coupling agent (F) in the first component and / or the second component.

[0425] [C10] A curable resin composition according to any one of [C1] to [C9], wherein the first component further comprises an epoxy silane coupling agent (F1).

[0426] [C11] A curable resin composition according to any one of [C1] to [C10], wherein the shell layer has epoxy groups.

[0427] [C12] A curable resin composition according to any one of [C1] to [C11], wherein the shell layer is a polymer formed by grafting an epoxy-based monomer component onto the core layer.

[0428] [C13] A curable resin composition according to any one of [C1] to [C12], wherein the shell layer has epoxy groups.

[0429] Relative to the total weight of the shell, the content of the epoxy groups in the shell is greater than 0 mmol / g and less than 2.0 mmol / g.

[0430] [C14] A curable resin composition according to any one of [C1] to [C13], wherein the shell layer does not have epoxy groups.

[0431] [C15] A curable resin composition according to any one of [C1] to [C14], wherein the compound (G) does not have any substituents other than the phenolic hydroxyl group on the aromatic ring.

[0432] [C16] A cured product, which is formed by curing the curable resin composition described in any one of [C1] to [C15].

[0433] [C17] An adhesive comprising any one of the curable resin compositions described in [C1] to [C15].

[0434] [C18] The adhesive according to [C17], wherein the adhesive is an adhesive for secondary batteries.

[0435] [C19] A laminate comprising:

[0436] 2 substrates, and

[0437] The adhesive described in [C17] or [C18] is used to form an adhesive layer between the two substrates.

[0438] One embodiment of the present invention may have the following configuration.

[0439] [X1] A curable resin composition, which is a two-component curable resin composition, comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), the curable resin composition further comprising polymer particles (B) and aluminum hydroxide (C), the polymer particles (B) having a core-shell structure comprising a core layer and a shell layer, wherein the total weight of the aluminum hydroxide (C) in 100% by weight of the curable resin composition is 55% by weight or more and 85% by weight or less, and the average particle size of the aluminum hydroxide (C) is 11 μm or more and 200 μm or less.

[0440] [X2] According to the curable resin composition of [X1], wherein the average particle size of the polymer particles (B) is 0.15 μm or more and 0.30 μm or less, the weight ratio of the core layer to the shell layer in the polymer particles (B) (weight of the core layer / weight of the shell layer) is 65 / 35 to 92 / 8, and the shell layer of the polymer particles (B) is a copolymer formed by polymerizing the following monomer components, wherein the monomer components contain 55 wt% or more of an alkyl ester of (meth)acrylic acid with 1 to 4 carbon atoms in 100 wt% of the monomer components, and wherein the monomer components contain 10 to 100 wt% of an alkyl ester of (meth)acrylic acid with 1 carbon atom and 0 to 80 wt% of an alkyl ester of (meth)acrylic acid with 4 carbon atoms in 100 wt% of the monomer components.

[0441] [X3] The curable resin composition according to [X1] or [X2], wherein the epoxy curing agent (D) is selected from one or more of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0442] [X4] The curable resin composition according to [X1] or [X2], wherein the curable resin composition further contains a compound (G), said compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, wherein the number of tertiary alkyl groups located at the adjacent positions of the phenolic hydroxyl groups in said compound (G) is 0 or 1 in one molecule, and said epoxy curing agent (D) is selected from at least one of aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0443] [X5] The curable resin composition according to any one of [X1] to [X4], wherein the ratio of the number of moles of epoxy groups in the epoxy resin (A) to the number of moles of active hydrogen groups in the epoxy curing agent (D) (the number of moles of epoxy groups in the epoxy resin (A) / the number of moles of active hydrogen groups in the epoxy curing agent (D)) is 0.5 or more and 1.5 or less.

[0444] [X6] The curable resin composition according to any one of [X1] to [X5], wherein the polymer particles (B) have a diene rubber in the core layer, wherein the diene rubber is butadiene rubber and / or styrene-butadiene rubber.

[0445] [X7] The curable resin composition according to any one of [X1] to [X6], wherein the polymer particles (B) having a core-shell structure have epoxy groups in the shell layer.

[0446] [X8] The curable resin composition according to any one of [X1] to [X7], wherein the polymer particles (B) have epoxy groups in the shell layer, and the content of the epoxy groups in the shell layer is 0.1 to 2.0 mmol / g or less relative to the total amount of the shell layer.

[0447] [X9] The curable resin composition according to any one of [X1] to [X6], wherein the polymer particles (B) do not contain epoxy groups in the shell layer.

[0448] [X10] A cured product, which is formed by curing the curable resin composition described in any one of [X1] to [X9].

[0449] [X11] An adhesive comprising any one of [X1] to [X9] of a curable resin composition.

[0450] [X12] The adhesive according to [X11], wherein the adhesive is an adhesive for secondary batteries.

[0451] [X13] A laminate comprising two substrates and an adhesive layer formed by curing the adhesive described in [X12], wherein the adhesive layer bonds the two substrates together.

[0452] [X14] A curable resin composition, which is a two-component curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D).

[0453] The curable resin composition further comprises polymer particles (B) and aluminum hydroxide (C), wherein the polymer particles (B) have a core-shell structure comprising a core layer and a shell layer, wherein the total weight of the aluminum hydroxide (C) in 100% by weight of the curable resin composition is 55% by weight or more and 85% by weight or less, wherein the average particle size of the polymer particles (B) is 0.15 μm or more and 0.30 μm or less, wherein the weight ratio of the core layer to the shell layer in the polymer particles (B) (weight of the core layer / weight of the shell layer) is 65 / 35 to 92 / 8, wherein the shell layer of the polymer particles (B) is a copolymer formed by polymerizing the following monomer components, wherein 100% by weight of the monomer components contains 55 wt% or more of an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms, and wherein the monomer components contain 10 to 100 wt% of an alkyl ester of (meth)acrylic acid having 1 carbon atom and 0 to 80 wt% of an alkyl ester of (meth)acrylic acid having 4 carbon atoms.

[0454] [X15] A curable resin composition, which is a two-component or multi-component curable resin composition, comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), the curable resin composition further comprising polymer particles (B) and a compound (G), the polymer particles (B) having a core-shell structure comprising a core layer and a shell layer, the compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, wherein the number of tertiary alkyl groups located at the adjacent positions of the phenolic hydroxyl groups in the compound (G) is 0 or 1 in one molecule, the epoxy curing agent (D) being at least one selected from aliphatic amines, alicyclic amines, amide amines, amino-terminated polyethers, amino-terminated nitrile rubber, modified aliphatic amines, modified alicyclic amines, modified amide amines, modified amino-terminated polyethers, and modified amino-terminated nitrile rubber.

[0455] Example

[0456] [Example A]

[0457] Hereinafter, Example A will be used to further describe the first embodiment in detail, but the present invention is not limited to these Examples A.

[0458] (Determination of volume average particle size)

[0459] The average particle size of the polybutadiene rubber particles in the polybutadiene rubber latex and the core-shell polymer particles (B) in the core-shell polymer latex described in the manufacturing example was determined by the following method. The volume average particle size (Mv) of the particles dispersed in the aqueous latex was determined using a Microtrac UPA150 (manufactured by Nikkiso Corporation). The sample diluted with deionized water was used as the test sample. The refractive index of the input water and the refractive index of each core-shell polymer particle (B) were adjusted to a measurement time of 600 seconds and a signal level within the range of 0.6 to 0.8, and the sample concentration was measured.

[0460] A1. Formation of the nuclear layer

[0461] Manufacturing Example A1: Preparation of polybutadiene rubber latex (R-2)

[0462] In a pressure polymerizer, 200 parts by weight of water, 0.03 parts by weight of tripotassium phosphate, 0.002 parts by weight of disodium ethylenediaminetetraacetate (EDTA), 0.001 parts by weight of ferrous sulfate heptahydrate (FE), and 1.55 parts by weight of sodium dodecylbenzenesulfonate (SDBS) were added. While stirring, nitrogen replacement was carried out to remove oxygen. Then, 100 parts by weight of butadiene (Bd) was added to the system, and the temperature was raised to 45°C. Terpene hydrogen peroxide (PHP) and sodium formaldehyde sulfoxylate (SFS) were added sequentially to initiate polymerization. 0.025 parts by weight of PHP were added at 3, 5, and 7 hours after polymerization initiation. Additionally, 0.0006 parts by weight of EDTA and 0.003 parts by weight of FE were added at 4, 6, and 8 hours after polymerization initiation. Residual monomers were removed by devolatilization under reduced pressure at the 15th hour of polymerization, ending the polymerization and yielding a polybutadiene rubber latex (R-1) with polybutadiene rubber as the main component. The volume average particle size of the polybutadiene rubber particles contained in the obtained latex was 80 nm.

[0463] In a pressure polymerizer, 21 parts by weight of polybutadiene rubber latex (R-1) (containing 7 parts by weight of polybutadiene rubber), 185 parts by weight of deionized water, 0.03 parts by weight of tripotassium phosphate, 0.002 parts by weight of EDTA, and 0.001 parts by weight of FE were added. While stirring, nitrogen replacement was carried out to remove oxygen. Then, 93 parts by weight of Bd were added to the system, and the temperature was raised to 45°C. 0.02 parts by weight of PHP and 0.10 parts by weight of SFS were added sequentially to initiate polymerization. From the start of polymerization until the 24th hour, 0.025 parts by weight of PHP, 0.0006 parts by weight of EDTA, and 0.003 parts by weight of FE were added every 3 hours. At the 30th hour of polymerization, residual monomers were devolatilized under reduced pressure to terminate the polymerization, yielding polybutadiene rubber latex (R-2) with polybutadiene rubber as the main component. The volume average particle size of the polybutadiene rubber particles in the obtained latex was 200 nm.

[0464] A2. Preparation of core-shell polymer latex (shell formation)

[0465] Manufacturing Example A2-1; Preparation of Core-Shell Polymer Latex (AL-1)

[0466] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 262 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 87 parts by weight of polybutadiene rubber particles) and 57 parts by weight of deionized water were added, and the mixture was stirred at 60°C while undergoing nitrogen replacement. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomers (4 parts by weight of methyl methacrylate (MMA), 6 parts by weight of styrene (ST), 2 parts by weight of acrylonitrile (AN), and 1 part by weight of glycidyl methacrylate (GMA)) and 0.04 parts by weight of cumene hydroperoxide (CHP) was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and the mixture was stirred for another 2 hours to complete the polymerization, yielding an aqueous latex (AL-1) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The aqueous latex (AL-1) contains core-shell polymer particles with a volume average particle size of 0.21 μm. The epoxy group content is 0.5 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0467] Manufacturing Example A2-2; Preparation of Core-Shell Polymer Latex (AL-2)

[0468] By changing the shell monomer to 5 parts by weight of MMA, 6 parts by weight of ST, and 2 parts by weight of AN, an aqueous latex (AL-2) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example A2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (AL-2) was 0.21 μm. The epoxy group content was 0.0 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0469] Manufacturing Example A2-3; Preparation of Core-Shell Polymer Latex (AL-3)

[0470] By changing the shell monomers to 3 parts by weight of MMA, 6 parts by weight of ST, 2 parts by weight of AN, and 2 parts by weight of GMA, an aqueous latex containing core-shell polymer particles (AL-3) was obtained in the same manner as in Manufacturing Example A2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (AL-3) was 0.21 μm. The epoxy group content was 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0471] Manufacturing Example A2-4; Preparation of Core-Shell Polymer Latex (AL-4)

[0472] By changing the shell monomers to 1 part by weight of MMA, 6 parts by weight of ST, 2 parts by weight of AN, and 4 parts by weight of GMA, an aqueous latex containing core-shell polymer particles (AL-4) was obtained in the same manner as in Manufacturing Example A2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (AL-4) was 0.21 μm. The epoxy group content was 2.2 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0473] Manufacturing Example A2-5; Preparation of Core-Shell Polymer Latex (AL-5)

[0474] By changing the shell monomer to 13 parts by weight of MMA, an aqueous latex (AL-5) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example A2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (AL-5) was 0.21 μm. The epoxy group content was 0.0 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0475] A3. Preparation of dispersions (M) containing core-shell polymer particles (B) in curable resins.

[0476] Manufacturing Example A3-1; Preparation of Dispersion (AM-1)

[0477] 132g of methyl ethyl ketone (MEK) was introduced into a 1L mixing tank at 25°C. While stirring, 132g of core-shell polymer latex (AL-1) obtained in Manufacturing Example A2-1 (equivalent to 40g of core-shell polymer particles) was added. After uniform mixing, 200g of water was added at a feed rate of 80g / min. After the feed was completed, stirring was quickly stopped, resulting in a slurry consisting of floating agglomerates and a partially aqueous phase containing organic solvent. Then, 360g of the aqueous phase remaining in the agglomerates was discharged from the drain at the bottom of the tank. 90g of MEK was added to the resulting agglomerates and mixed uniformly to obtain a dispersion in which the core-shell polymer particles were uniformly dispersed. 60g of epoxy resin (A-1; manufactured by Mitsubishi Chemical Corporation, JER828: liquid bisphenol A type epoxy resin) as component (A) was mixed into this dispersion. MEK was removed from the mixture using a rotary evaporator. Thus, a dispersion (AM-1) containing core-shell polymer particles dispersed in epoxy resin was obtained.

[0478] Manufacturing Example A3-2; ​​Preparation of Dispersion (AM-2)

[0479] In manufacturing example A3-1, (AL-2) obtained in manufacturing example A2-2 was used instead of (AL-1) as the core-shell polymer latex. Otherwise, a dispersion (AM-2) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in manufacturing example A3-1.

[0480] Manufacturing Example A3-3; Preparation of Dispersion (AM-3)

[0481] In manufacturing example A3-1, (AL-3) obtained in manufacturing example A2-3 was used instead of (AL-1) as the core-shell polymer latex. Otherwise, a dispersion (AM-3) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in manufacturing example A3-1.

[0482] Manufacturing Example A3-4; Preparation of Dispersion (AM-4)

[0483] In manufacturing example A3-1, (AL-4) obtained in manufacturing example A2-4 was used instead of (AL-1) as the core-shell polymer latex. Otherwise, a dispersion (AM-4) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in manufacturing example A3-1.

[0484] Manufacturing Example A3-5; Preparation of Dispersion (AM-5)

[0485] In manufacturing example A3-1, (AL-5) obtained in manufacturing example A2-5 was used instead of (AL-1) as the core-shell polymer latex, and 60g of epoxy resin (A-2; manufactured by Hexion Corporation, EPON863: liquid bisphenol F type epoxy resin) was used instead of 60g of epoxy resin (A-1). Otherwise, a dispersion (AM-5) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in manufacturing example A3-1.

[0486] (Examples A1-17, Comparative Examples A1-8)

[0487] According to the formulations shown in Tables 1 to 3, each component was measured and thoroughly mixed to obtain the first and second components of the two-component curable resin composition.

[0488] For each two-component curable resin composition listed in Tables 1 to 3, dynamic splitting resistance (impact peel adhesion), shear bond strength, thermal conductivity, and flame retardancy (UL-94) were evaluated according to the following methods.

[0489] <Dynamic splitting resistance (impact peel adhesion)>

[0490] Each composition, obtained by thoroughly mixing the first and second components of Tables 1-3, was coated onto two cold-rolled steel sheets (SPCC-SD), laminated to form an adhesive layer thickness of 0.25 mm, and cured at 23°C for 7 days to obtain a laminate. Using this laminate, the dynamic splitting resistance (impact peel adhesion) was measured at 23°C according to ISO 11343. The results are shown in Tables 1-3.

[0491] <Shear bond strength>

[0492] Each composition obtained by thoroughly mixing the first and second components in Table 2 was coated onto two cold-rolled steel sheets (SPCC-SD) or aluminum sheets (A-5052P) with a width of 25 mm × length of 100 mm × thickness of 1.6 mm and bonded together, so that the adhesive layer had a width of 25 mm × length of 12.5 mm × thickness of 0.13 mm. The mixture was then cured at 23°C for 7 days to obtain a laminate.

[0493] The shear bond strength was measured under the conditions of a test temperature of 23℃ and a test speed of 1.3 mm / min, with the unit set to MPa. The results are shown in Table 2.

[0494] <thermal conductivity>

[0495] The compositions obtained by mixing the first and second components in Table 3 and then degassing them were injected between two glass plates with a 3 mm thick spacer. The mixtures were then cured at 23°C for 7 days to obtain a 3 mm thick cured plate. The cured plate was then cut to obtain two 20 mm diameter disc-shaped samples. The thermal conductivity of the cured product was measured using a Hot Disk thermal conductivity measuring apparatus TPA-501 (manufactured by Kyoto Electronics Industry Co., Ltd.) by clamping a 4φ sensor between the two samples.

[0496] <Flame retardancy>

[0497] The compositions obtained by mixing the first and second components of Table 3 and degassing them were injected between two glass plates with a 3 mm thick spacer. The mixtures were then cured at 23°C for 7 days to obtain a 3 mm thick cured plate. This cured plate was cut into rectangles measuring 127 mm × 12.7 mm × 3 mm and evaluated according to the UL-94 20 mm vertical burning test (V test). Test results were indicated in the order of "V-0", "V-1", and "V-2" starting with good flame retardancy. Those failing the UL-94 V test were considered "non-compliant".

[0498] It should be noted that the various compounding agents in Tables 1 to 3 use the substances shown below.

[0499] <Epoxy Resin (A)>

[0500] A-1: JER828 (manufactured by Mitsubishi Chemical Corporation, a bisphenol A type epoxy resin that is liquid at room temperature, epoxy equivalent: 184-194)

[0501] A-2: EPON863 (manufactured by Hexion, bisphenol F type epoxy resin, liquid at room temperature, epoxy equivalent: 165-174)

[0502] A-3: YED216M (manufactured by Mitsubishi Chemical Corporation, alkyl diglycidyl ether, epoxy equivalent: 140-160)

[0503] <Dispersion (M) in epoxy resin (A) containing polymer particles (B)>

[0504] AM-1~5: Dispersions obtained in the above manufacturing examples A3-1~5

[0505] <Aluminum hydroxide (C)>

[0506] C-1: B303 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 26μm)

[0507] C-2: B303STE (manufactured by Nippon Light Metals Co., Ltd., aluminum hydroxide treated with epoxy silane coupling agent, average particle size (Dp50): 17μm)

[0508] C-3: B53 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 57μm)

[0509] C-4: SB93 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 114μm)

[0510] C-5: BE033 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 3.2μm)

[0511] C-6: BE043STE (manufactured by Nippon Light Metals Co., Ltd., aluminum hydroxide treated with epoxy silane coupling agent, average particle size (Dp50): 3.7μm)

[0512] C-7: BF013 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 1.2μm)

[0513] C-8: BF013ST (manufactured by Nippon Light Metals Co., Ltd., aluminum hydroxide treated with epoxy silane coupling agent, average particle size (Dp50): 1.2μm)

[0514] <Epoxy Curing Agent (D)>

[0515] D-1: 1,3-bis(aminomethyl)cyclohexane (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., active hydrogen equivalent: 35.5 g / eq)

[0516] D-2: Jeffamine T-5000 (manufactured by Huntsman Corporation, glycerol poly(propylene oxide)triamine, molecular weight: approx. 5000, active hydrogen equivalent: 952 g / eq)

[0517] D-3: Hypro ATBN 1300x16 (manufactured by Huntsman, amino-terminated butadiene-acrylonitrile copolymer, molecular weight: approx. 3800, active hydrogen equivalent: 800-1000 g / eq)

[0518] D-4: Isophorone diamine (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd., active hydrogen equivalent: 41 g / eq)

[0519] <Epoxy Curing Accelerator (E)>

[0520] E-1: Resorcinol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0521] <Epoxysilane Coupling Agent (F)>

[0522] F-1: DOWSIL Z-6040Silane (manufactured by Dow Toray)

[0523]

[0524] As shown in Table 1, for the two-component curable resin compositions of Examples A1 to 8, which contain components (A), (B), and (C) in the first component and components (C) and (D) in the second component, the resulting cured products have high dynamic splitting resistance and good impact peel adhesion.

[0525] The compositions of Examples A1, 3-8 and Comparative Examples A1-5 differ only in the type of component (C); all other components are identical. The aluminum hydroxide used in the compositions of Examples A1, 3-8 has a larger average particle size, while the aluminum hydroxide used in the compositions of Comparative Examples A1-5 has a smaller average particle size and lower impact peel adhesion compared to Examples A1, 3-8.

[0526] The composition of Example A2 is a combination of the composition of Example A1 with the addition of epoxy curing accelerator (E), and it is known that it also has excellent impact peel adhesion.

[0527]

[0528] As shown in Table 2, the two-component curable resin compositions of Examples A9-14, which contain components (A), (B) and (C) in the first component and components (C) and (D) in the second component, maintain a high level of shear adhesion to steel and aluminum plates and produce cured products with good impact peel adhesion.

[0529] The compositions of Examples A9-11 and Comparative Example A6 differ only in the type of component (C); all other components are identical. The aluminum hydroxide used in the compositions of Examples A9-11 has a larger average particle size, while the aluminum hydroxide used in the composition of Comparative Example A6 has a smaller average particle size and lower impact peel adhesion compared to Examples A9-11.

[0530] The compositions of Examples A9, 12-14 differ only in the addition of component (B); all other components are identical. The epoxy group content of the shell layer of component (B) used in the compositions of Examples A9, 12-14 differs. Better impact-peel adhesion was observed when the shell layer contained no epoxy groups (Example A12), and when the epoxy group content of the shell layer was 0.5 mmol / g (Example A9) and 1.1 mmol / g (Example A13).

[0531]

[0532] As shown in Table 3, the two-component curable resin compositions of Examples A15-17, which contain components (A), (B) and (C) in the first component and components (C) and (D) in the second component, have high thermal conductivity, excellent flame retardancy, and good impact peel adhesion of the cured products.

[0533] The compositions of Examples A15-17 and Comparative Example A7 differed only in the amount of component (C); all other components were identical. In Comparative Example A7, where the total weight of component (C) was less than the total weight of the cured resin composition, the thermal conductivity was low, resulting in a failure to meet the UL-94 flame retardancy standard. Similarly, in Comparative Example A8, which did not contain component (C), the thermal conductivity was low, also resulting in a failure to meet the UL-94 flame retardancy standard.

[0534] [Example B]

[0535] The second embodiment will be further described in detail below with reference to Embodiment B, but the present invention is not limited to these Embodiment B.

[0536] (Determination of volume average particle size)

[0537] The method for determining the average particle size of polybutadiene rubber particles in polybutadiene rubber latex and core-shell polymer particles in core-shell polymer latex as described in Manufacturing Example B is the same as the method described in the (Determination of Volume Average Particle Size) section of [Example A] above. Therefore, the description in the (Determination of Volume Average Particle Size) section of [Example A] above will be referenced here, and its explanation will be omitted.

[0538] B1. Formation of the nuclear layer

[0539] In Example B, R-2 obtained by the method described in the "Manufacturing Example A1; Preparation of Polybutadiene Rubber Latex (R-2)" section of Example A was used as the core layer. Therefore, the description of the "Manufacturing Example A1; Preparation of Polybutadiene Rubber Latex (R-2)" section of Example A is referenced here, and its explanation is omitted here.

[0540] B2. Preparation of core-shell polymer latex (shell formation)

[0541] Manufacturing Example B2-1; Preparation of Core-Shell Polymer Latex (BL-1)

[0542] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 271 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 90 parts by weight of polybutadiene rubber particles) and 51 parts by weight of deionized water were added, and the mixture was stirred at 60°C while undergoing nitrogen replacement. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomers (9 parts by weight of methyl methacrylate (MMA) and 1 part by weight of glycidyl methacrylate (GMA)) and 0.14 parts by weight of cumene hydroperoxide (CHP) was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and the mixture was stirred for another 2 hours to complete the polymerization, yielding an aqueous latex (BL-1) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The aqueous latex (BL-1) contains core-shell polymer particles with a volume average particle size of 0.21 μm. The epoxy group content is 0.7 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0543] Manufacturing Example B2-2; Preparation of Core-Shell Polymer Latex (BL-2)

[0544] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 262 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 87 parts by weight of polybutadiene rubber particles) and 57 parts by weight of deionized water were added, and nitrogen replacement was carried out while stirring at 60°C. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomers (11 parts by weight of MMA and 2 parts by weight of GMA) and 0.06 parts by weight of CHP was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, yielding an aqueous latex (BL-2) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-2) was 0.21 μm. The content of epoxy groups is 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0545] Manufacturing Example B2-3; Preparation of Core-Shell Polymer Latex (BL-3)

[0546] By changing the shell monomer to 2 parts by weight of MMA, 9 parts by weight of butyl acrylate (BA), and 2 parts by weight of GMA, an aqueous latex containing core-shell polymer particles (BL-3) was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-3) was 0.21 μm. The epoxy group content was 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0547] Manufacturing Example B2-4; Preparation of Core-Shell Polymer Latex (BL-4)

[0548] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 223 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 74 parts by weight of polybutadiene rubber particles) and 83 parts by weight of deionized water were added, and the mixture was stirred at 60°C while undergoing nitrogen replacement. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomers (4 parts by weight of MMA, 18 parts by weight of BA, and 4 parts by weight of GMA) and 0.12 parts by weight of CHP was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and the mixture was stirred for another 2 hours to complete the polymerization, yielding an aqueous latex (BL-4) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-4) was 0.22 μm. The content of epoxy groups is 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0549] Manufacturing Example B2-5; Preparation of Core-Shell Polymer Latex (BL-5)

[0550] By changing the shell monomer to 11 parts by weight of BA and 2 parts by weight of GMA, an aqueous latex (BL-5) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-5) was 0.21 μm. The epoxy group content was 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0551] Manufacturing Example B2-6; Preparation of Core-Shell Polymer Latex (BL-6)

[0552] By changing the shell monomers to 1 part by weight of MMA, 6 parts by weight of ST, 2 parts by weight of AN, and 4 parts by weight of GMA, an aqueous latex containing core-shell polymer particles (BL-6) was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-6) was 0.21 μm. The epoxy group content was 2.2 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0553] Manufacturing Example B2-7; Preparation of Core-Shell Polymer Latex (BL-7)

[0554] By changing the shell monomer to 8 parts by weight of MMA and 2 parts by weight of GMA, an aqueous latex (BL-7) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-7) was 0.21 μm. The epoxy group content was 1.4 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0555] Manufacturing Example B2-8; Preparation of Core-Shell Polymer Latex (BL-8)

[0556] By changing the shell monomer to 6 parts by weight of MMA and 4 parts by weight of GMA, an aqueous latex (BL-8) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-1. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-8) was 0.21 μm. The epoxy group content was 2.8 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0557] Manufacturing Example B2-9; Preparation of Core-Shell Polymer Latex (BL-9)

[0558] By changing the shell monomer to 6 parts by weight of MMA and 7 parts by weight of BA, an aqueous latex (BL-9) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-9) was 0.21 μm. The epoxy group content relative to the total amount of the shell of the core-shell polymer particles was 0 mmol / g.

[0559] Manufacturing Example B2-10; Preparation of Core-Shell Polymer Latex (BL-10)

[0560] By changing the shell monomers to 5 parts by weight of MMA, 6 parts by weight of BA, and 2 parts by weight of GMA, an aqueous latex (BL-10) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-10) was 0.21 μm. The epoxy group content was 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0561] Manufacturing Example B2-11; Preparation of Core-Shell Polymer Latex (BL-11)

[0562] By changing the shell monomer to 13 parts by weight of MMA, an aqueous latex (BL-11) containing core-shell polymer particles was obtained in the same manner as in Manufacturing Example B2-2. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-11) was 0.21 μm. The epoxy group content relative to the total amount of the shell of the core-shell polymer particles was 0 mmol / g.

[0563] Manufacturing Example B2-12; Preparation of Core-Shell Polymer Latex (BL-12)

[0564] By changing the shell monomers to 4 parts by weight of MMA, 8 parts by weight of BA, 10 parts by weight of butyl methacrylate (BMA), and 4 parts by weight of GMA, an aqueous latex containing core-shell polymer particles (BL-12) was obtained in the same manner as in Manufacturing Example B2-4. The monomer conversion rate was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-12) was 0.22 μm. The epoxy group content was 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0565] Manufacturing Example B2-13; Preparation of Core-Shell Polymer Latex (BL-13)

[0566] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 241 parts by weight of polybutadiene rubber latex (R-1) prepared in Manufacturing Example A1 (containing 80 parts by weight of polybutadiene rubber particles) and 71 parts by weight of deionized water were added, and nitrogen replacement was carried out while stirring at 60°C. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomer (20 parts by weight of MMA) and CHP was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, yielding an aqueous latex (BL-13) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The volume average particle size of the core-shell polymer particles contained in the aqueous latex (BL-13) was 0.09 μm. The content of epoxy groups is 0 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0567] Manufacturing Example B2-14; Preparation of Core-Shell Polymer Latex (BL-14)

[0568] In a glass reactor equipped with a thermometer, stirrer, reflux cooler, nitrogen inlet, and monomer addition device, 145 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 48 parts by weight of polybutadiene rubber particles) and 135 parts by weight of deionized water were added, and the mixture was stirred at 60°C while undergoing nitrogen replacement. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.3 parts by weight of SFS, a mixture of shell monomers (8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, and 8 parts by weight of GMA) and 0.24 parts by weight of CHP was continuously added over 240 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and the mixture was stirred for another 2 hours to complete the polymerization, yielding an aqueous latex (BL-14) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was over 99%. The aqueous latex (BL-14) contains core-shell polymer particles with a volume average particle size of 0.24 μm. The epoxy group content is 1.1 mmol / g relative to the total amount of the shell of the core-shell polymer particles.

[0569] B3. Preparation of dispersions (M) containing core-shell polymer particles (B) in curable resins

[0570] Manufacturing Example B3-1; Preparation of Dispersion (BM-1)

[0571] 132g of methyl ethyl ketone (MEK) was introduced into a 1L mixing tank at 25°C. While stirring, 132g of core-shell polymer latex (BL-1) obtained in Manufacturing Example B2-1 (equivalent to 40g of core-shell polymer particles) was added. After uniform mixing, 200g of water was added at a feed rate of 80g / min. After the feed was completed, stirring was quickly stopped, resulting in a slurry consisting of floating agglomerates and a partially aqueous phase containing organic solvent. Then, 360g of the aqueous phase remaining in the agglomerates was discharged from the drain at the bottom of the tank. 90g of MEK was added to the resulting agglomerates and mixed uniformly to obtain a dispersion in which the core-shell polymer particles were uniformly dispersed. 60g of epoxy resin (manufactured by Mitsubishi Chemical Corporation, JER828: liquid bisphenol A type epoxy resin) as component (A) was mixed into this dispersion. MEK was removed from the mixture using a rotary evaporator. Thus, a dispersion (BM-1) containing core-shell polymer particles dispersed in epoxy resin was obtained.

[0572] Manufacturing Examples B3-2 to 3-14; Preparation of Dispersions (BM-2) to (BM-14)

[0573] In manufacturing example B3-1, (BL-2) to (BL-14) obtained in manufacturing examples B2-2 to B2-14 were used instead of (BL-1) as the core-shell polymer latex. Otherwise, dispersions (BM-2) to (BM-14) in which core-shell polymer particles are dispersed in epoxy resin were obtained in the same manner as in manufacturing example B3-1.

[0574] (Examples B1-17, Comparative Examples B1-6)

[0575] According to the formulations shown in Tables 4 to 7, each component was measured and thoroughly mixed to obtain the first and second components of the two-component curable resin composition.

[0576] For each two-component curable resin composition listed in Tables 4 to 7, viscosity, shear bond strength, dynamic splitting resistance (impact peel bond), thermal conductivity, and flame retardancy (UL-94) were evaluated according to the following methods.

[0577] <Viscosity>

[0578] Using a rheometer, at a shear rate of 5s -1 The viscosities of the first or second component (Tables 4-7) at 25°C were measured. Lower viscosity values ​​indicate better operability.

[0579] <Shear bond strength>

[0580] Each composition obtained by thoroughly mixing the first and second components in Tables 4 to 6 was coated onto two SPCC steel or aluminum plates (A-5052P) with a width of 25mm, a length of 100mm, and a thickness of 1.6mm and bonded together, so that the adhesive layer had a width of 25mm, a length of 12.5mm, and a thickness of 0.13mm. The plates were then cured at 23℃ for 7 days to obtain a laminate.

[0581] The shear bond strength was determined under the conditions of a test temperature of 23℃ and a test speed of 1.3 mm / min, with the unit set to MPa.

[0582] <Dynamic splitting resistance (impact peel adhesion)>

[0583] Each composition obtained by thoroughly mixing the first and second components from Tables 5 and 6 was coated onto two SPCC steel plates, which were then stacked to achieve an adhesive layer thickness of 0.25 mm. The plates were then cured at 23°C for 7 days to obtain a laminate. Using this laminate, the dynamic splitting resistance (impact peel adhesion) was measured at 23°C according to ISO 11343.

[0584] <thermal conductivity>

[0585] The compositions obtained by mixing the first and second components in Table 7 and then degassing them were injected between two glass plates with a 3 mm thick spacer. The mixtures were then cured at 23°C for 7 days to obtain a 3 mm thick cured plate. The cured plate was then cut to obtain two 20 mm diameter disc-shaped samples. The thermal conductivity of the cured product was measured using a Hot Disk thermal conductivity measuring apparatus TPA-501 (manufactured by Kyoto Electronics Industry Co., Ltd.) by clamping a 4φ sensor between the two samples.

[0586] <Flame retardancy>

[0587] The compositions obtained by mixing the first and second components in Table 7 and then degassing them were injected between two glass plates with a 3 mm thick spacer. The mixtures were then cured at 23°C for 7 days to obtain a 3 mm thick cured plate. This cured plate was cut into rectangles measuring 127 mm × 12.7 mm × 3 mm and evaluated according to the UL-94 20 mm vertical burning test (V test). Test results were indicated in the order of "V-0", "V-1", and "V-2" starting with good flame retardancy. Those failing the UL-94 V test were considered "non-compliant".

[0588] It should be noted that the various compounding agents in Tables 4 to 7 use the substances shown below.

[0589] <Epoxy Resin (A)>

[0590] A-1: JER828 (manufactured by Mitsubishi Chemical Corporation, a bisphenol A type epoxy resin that is liquid at room temperature, epoxy equivalent: 184-194)

[0591] A-2: YED216M (manufactured by Mitsubishi Chemical Corporation, alkyl diglycidyl ether, epoxy equivalent: 140-160)

[0592] <Dispersion (M) in epoxy resin (A) containing polymer particles (B)>

[0593] BM-1~14: Dispersions obtained in manufacturing examples B3-1~14 above

[0594] <Aluminum hydroxide (C)>

[0595] C-1: B303 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 26μm)

[0596] C-2: BE033 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 3.2μm)

[0597] <Epoxy Curing Agent (D)>

[0598] D-1: 1,3-bis(aminomethyl)cyclohexane (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0599] D-2: Jeffamine T-5000 (manufactured by Huntsman Corporation, glycerol poly(propylene oxide)triamine, molecular weight: approx. 5000, active hydrogen equivalent: 952 g / eq)

[0600] D-3: Hypro ATBN 1300x16 (manufactured by Huntsman, amino-terminated butadiene-acrylonitrile copolymer, molecular weight: approx. 3800, active hydrogen equivalent: 800-1000 g / eq)

[0601] <Epoxy Curing Accelerator (E)>

[0602] E-1: Resorcinol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0603] <Epoxysilane Coupling Agent (F)>

[0604] F-1: DOWSIL Z-6040Silane (manufactured by Dow Toray)

[0605]

[0606] As shown in Table 4, the two-component curable resin compositions of Examples B1 to 4, which contain components (A), (B), and (C) in the first component and components (C) and (D) in the second component, have low viscosity, excellent workability, and good shear adhesion of the cured product.

[0607] The compositions of Examples B1-4 and Comparative Examples B1-2 differed only in the addition of component (B); all other components were identical. For component (B) used in the compositions of Examples B1-4, the main component (55% by weight or more) of alkyl esters (meth)acrylate with 1-4 carbon atoms was used as the main component, and the content of alkyl esters (meth)acrylate with 4 carbon atoms was 80% by weight or less. On the other hand, Comparative Example B1, with a shell containing 85% alkyl esters (meth)acrylate with 4 carbon atoms, had a very high viscosity and poor workability; therefore, shear bond strength was not measured. Furthermore, compared to Examples B1-4, Comparative Example B2, with a shell containing as little as 8% alkyl esters (meth)acrylate with 1-4 carbon atoms and other monomer components as the main components, exhibited a high viscosity of the first component and low shear bond strength of the resulting cured product.

[0608]

[0609] As shown in Table 5, the two-component curable resin compositions of Examples B5-10 are similar to those of Examples B1-4 in Table 4, exhibiting low viscosity and excellent workability.

[0610] Examples B1 and B2 have the same first component, but the second component of Example B2 reduces the amount of each compounding agent added in the second component of Example B1 to 0.75 times. As a result, the ratio of the number of moles of epoxy groups in component (A) to the number of moles of active hydrogen groups in component (D) of Example B2 is high, making it an epoxy-excess composition, and the shear adhesion shows a very low value.

[0611] The compositions of Examples B5, 7-10 differ only in the addition of component (B); all other components are identical. The composition of Example B8, which has a high content of epoxy groups in the shell of component (B), exhibits a very low impact peel adhesion value. Furthermore, the composition of Example B9, which does not contain epoxy groups in the shell of component (B), also exhibits a low impact peel adhesion value. This result indicates that the molar ratio of epoxy groups in component (A) to the molar ratio of active hydrogen groups in component (D) is effective for shear bond strength, and the amount of epoxy groups in the shell of component (B) is effective for impact peel adhesion.

[0612]

[0613] As shown in Table 6, the two-component curable resin compositions of Examples B11-14 have low viscosity, excellent workability, and good shear adhesion and impact peel adhesion of the cured products.

[0614] The compositions of Examples B11-14 and Comparative Examples B3-5 differed only in the addition of component (B); all other components were identical. The composition of component (B) used in Examples B11-14 had an average particle size of 0.15-0.30 μm, a core / shell weight ratio of 65 / 35-92 / 8, and the shell monomer was primarily composed of an alkyl ester of (meth)acrylic acid with 1-4 carbon atoms (55% by weight or more). On the other hand, the compositions of Comparative Example B3 (with as little as 8% by weight of alkyl esters of (meth)acrylic acid with 1-4 carbon atoms), Comparative Example B4 (with an average particle size of component (B) as small as 0.09 μm), and Comparative Example B5 (with a core / shell weight ratio of 48 / 52) all exhibited high viscosity of the first component and poor operability. Furthermore, since the composition of Comparative Example B5 exhibited a very low value for impact peel adhesion, it can be considered that the core / shell weight ratio of component (B) is effective for impact peel adhesion. Additionally, the compositions of Examples B12 and Comparative Example B4, whose shells of component (B) do not contain epoxy groups, also exhibited low values ​​for impact peel adhesion. Based on these results, it can be considered that the amount of epoxy groups in the shell of component (B) is effective for impact peel adhesion.

[0615]

[0616] As shown in Table 7, the two-component curable resin compositions of Examples B15-17, which contain components (A), (B), and (C) in the first component and components (C) and (D) in the second component, have high thermal conductivity, excellent flame retardancy, low viscosity, and excellent workability.

[0617] The compositions of Examples B15-17 and Comparative Example B6 differed only in the amount of component (C); all other components were identical. In Comparative Example B6, where the total weight of component (C) was less than the total weight of the cured resin composition, the thermal conductivity was lower, resulting in a failure to meet the UL-94 flame retardancy standard.

[0618] [Example C]

[0619] The second embodiment will be further described in detail below with reference to Embodiment C, but the present invention is not limited to these Embodiment C.

[0620] (Determination of volume average particle size)

[0621] The method for determining the average particle size of polybutadiene rubber particles in polybutadiene rubber latex and core-shell polymer particles in core-shell polymer latex as described in Manufacturing Example C is the same as the method described in the (Determination of Volume Average Particle Size) section of [Example A] above. Therefore, the description in the (Determination of Volume Average Particle Size) section of [Example A] above will be omitted here.

[0622] C1. Formation of the nuclear layer

[0623] In Example C, R-2 obtained by the method described in the "Manufacturing Example A1; Preparation of Polybutadiene Rubber Latex (R-2)" section of Example A was used as the core layer. Therefore, the description of the "Manufacturing Example A1; Preparation of Polybutadiene Rubber Latex (R-2)" section of Example A is referenced here, and its explanation is omitted here.

[0624] C2. Preparation of core-shell polymer latex (shell formation)

[0625] Manufacturing Example C2-1; Preparation of Core-Shell Polymer Latex (CL-1)

[0626] In a glass reactor equipped with a thermometer, a stirrer, a reflux cooler, a nitrogen inlet, and a monomer addition device, 262 parts by weight of polybutadiene rubber latex (R-2) prepared in Manufacturing Example A1 (containing 87 parts by weight of polybutadiene rubber particles) and 57 parts by weight of deionized water were added, and the mixture was stirred at 60°C while undergoing nitrogen replacement. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.2 parts by weight of SFS, a mixture of shell monomers (3 parts by weight of methyl methacrylate (MMA), 6 parts by weight of styrene (ST), 2 parts by weight of acrylonitrile (AN), 2 parts by weight of glycidyl methacrylate (GMA), and 0.04 parts by weight of cumene hydroperoxide (CHP)) was continuously added over 120 minutes. After the addition was completed, 0.04 parts by weight of CHP was added, and the mixture was stirred for another 2 hours to complete the polymerization, yielding an aqueous latex (CL-1) containing core-shell polymer particles (B). The polymerization conversion rate of the monomer components is over 99%. The volume average particle size of the core-shell polymer particles (B) contained in the aqueous latex (CL-1) is 0.21 μm.

[0627] C3. Preparation of dispersions (M) of core-shell polymer particles (B) in curable resins

[0628] Manufacturing Example C3-1; Preparation of Dispersion (M-1)

[0629] 132g of methyl ethyl ketone (MEK) was introduced into a 1L mixing tank at 25°C. While stirring, 132g of core-shell polymer latex (CL-1) obtained in Manufacturing Example C2-1 (equivalent to 40g of core-shell polymer particles (B)) was added. After uniform mixing, 200g of water was added at a feed rate of 80g / min. After the feed was completed, stirring was quickly stopped, resulting in a slurry consisting of floating agglomerates and a partially aqueous phase containing organic solvent. Then, 360g of the aqueous phase remaining in the agglomerates was discharged from the drain at the bottom of the tank. 90g of MEK was added to the resulting agglomerates and mixed uniformly to obtain a dispersion in which the core-shell polymer particles (B) were uniformly dispersed. 60g of epoxy resin (A-1; manufactured by Mitsubishi Chemical Corporation, JER828: liquid bisphenol A type epoxy resin, epoxy equivalent: 184~194g / eq) as component (A) was mixed into this dispersion. MEK was removed from the mixture using a rotary evaporator. This yielded a dispersion (M-1) containing core-shell polymer particles (B) dispersed in epoxy resin.

[0630] Manufacturing Example C3-2; Preparation of Dispersion (M-2)

[0631] In manufacturing example C3-1, 60g of epoxy resin (A-2; manufactured by Hexion Corporation, EPON863: bisphenol F type epoxy resin, epoxy equivalent: 165-174g / eq) was used instead of 60g of epoxy resin (A-1). Otherwise, a dispersion (M-2) in which core-shell polymer particles (B) were dispersed in epoxy resin was obtained in the same manner as in manufacturing example C3-1.

[0632] (Examples C1-23, Comparative Examples C1-7)

[0633] According to the formulations shown in Tables 8 to 12, each component was measured and thoroughly mixed to obtain the first and second components of the two-component curable resin composition. The two-component curable resin compositions obtained in Examples C1 to 23 are the curable resin compositions (two-component curable resin compositions) of Embodiment 3.

[0634] For each two-component curable resin composition in Table 8 or 9, the curing time was evaluated according to the following method.

[0635] <Curing Time>

[0636] Using a Bohlin CVO rheometer manufactured by Malvern, with a PP25 plate, a shear rate of 5 s was applied at a plate gap of 0.2 mm. -1The viscosity change over time of each two-component curable resin composition obtained by thoroughly mixing the first and second components from Table 8 or 9 was determined at 50°C. Viscosity was measured every 10 seconds, and the viscosity immediately after mixing the first and second components was taken as the initial viscosity. The time taken to reach 10 times the initial viscosity was taken as the curing time. The shorter the curing time, the better the curing performance.

[0637] The shear bond strength of each two-component curable resin composition listed in Tables 8 to 12 was evaluated using the following method.

[0638] <Shear bond strength>

[0639] The two-component curable resin compositions obtained by thoroughly mixing the first and second components in Tables 8 to 12 were coated onto two aluminum plates (A-5052P) or cold-rolled steel plates with a width of 25 mm × length of 100 mm × thickness of 1.6 mm and bonded together, so that the coated two-component curable resin composition (adhesive layer) has a width of 25 mm × length of 12.5 mm × thickness of 0.25 mm. The mixture was cured at 23°C for 7 days to obtain a laminate.

[0640] The shear bond strength was determined under the conditions of a test temperature of 23℃ and a test speed of 1.3 mm / min, with the unit set to MPa. The results are shown in Tables 8 to 12.

[0641] For each two-component curable resin composition in Table 10, the dynamic splitting resistance (impact peel adhesion) was evaluated using the following method.

[0642] <Dynamic splitting resistance (impact peel adhesion)>

[0643] The compositions obtained by thoroughly mixing the first and second components of Table 10 were coated onto two cold-rolled steel sheets, which were then laminated to form an adhesive layer thickness of 0.25 mm. The laminates were cured at 23°C for 7 days to obtain a laminate. Using this laminate, the dynamic splitting resistance (impact peel adhesion) was measured at 23°C according to ISO 11343. The results are shown in Table 10.

[0644] It should be noted that the various compounding agents in Tables 8 to 12 use the substances shown below.

[0645] <Epoxy Resin (A)>

[0646] A-1: JER828 (manufactured by Mitsubishi Chemical Corporation, a bisphenol A type epoxy resin that is liquid at room temperature, epoxy equivalent: 184-194)

[0647] A-2: EPON863 (manufactured by Hexion, bisphenol F type epoxy resin, epoxy equivalent: 165-174)

[0648] <Dispersion (M) of epoxy resin (A) containing core-shell polymer particles (B)>

[0649] CM-1~2: Dispersions obtained in manufacturing examples C3-1~2 above.

[0650] <Compound (G)>

[0651] Resorcinol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0652] Catechol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0653] 4-Ter-Butylcatechol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0654] Methylhydroquinone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0655] tert-Butylhydroquinone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0656] <Compounds with phenolic hydroxyl groups that are different from component (G)>

[0657] 2,5-Di-tert-butylhydroquinone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0658] 2,4,6-Tris(dimethylaminomethyl)phenol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0659] 4-tert-Butylphenol (manufactured by Tokyo Chemical Co., Ltd.)

[0660] Phenol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0661] 4-Methoxyphenol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0662] <Epoxy Curing Agent (D)>

[0663] D-1 (Alicyclic Amine): 1,3-Bis(aminomethyl)cyclohexane (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.)

[0664] D-2 (amino-terminated polyether): Ancamine 1922A (manufactured by Evonik, 3,3'-[oxybis(2,1-ethylenedioxy)]bis-1-propylamine (3,3'-(Oxybis(2,1-ethane-diyloxy))bis-1-popanamine), active hydrogen equivalent: 55 g / eq)

[0665] D-3 (Aminobutadiene-acrylonitrile rubber): Hypro ATBN 1300x16 (manufactured by Huntsman Corporation, aminobutadiene-acrylonitrile copolymer, molecular weight: approx. 3800, active hydrogen equivalent: 800-1000 g / eq)

[0666] D-4 (Amideamine): Vegechem Green V140 (manufactured by Tsukino Foods Co., Ltd., dimer acid, condensate of fatty acids and polyamines, active hydrogen equivalent: 97g / eq)

[0667] D-5 (amino-terminated polyether): Jeffamine T-5000 (manufactured by Huntsman Corporation, glycerol poly(propylene oxide)triamine, molecular weight: approx. 5000, active hydrogen equivalent: 952 g / eq)

[0668] <Aluminum hydroxide (C)>

[0669] C-1: B303 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 26μm)

[0670] C-2: BE033 (manufactured by Nippon Light Metals Co., Ltd., untreated aluminum hydroxide, average particle size (Dp50): 3.2μm)

[0671] <Epoxysilane Coupling Agent (F)>

[0672] F-1: DOWSIL Z-6040Silane (manufactured by Dow Toray, 3-epoxypropoxypropyltrimethoxysilane)

[0673] F-2: KBM 603Silane (manufactured by Shin-Etsu Silicones Co., Ltd., N-2-(aminoethyl)-3-aminopropyltrimethoxysilane)

[0674] <Heavy calcium carbonate>

[0675] WHITON SB (manufactured by Shiraishi Calcium Co., Ltd., average particle size: 1.8 μm)

[0676] <Carbon Black>

[0677] MONARCH 280 (made by Cabot Corporation)

[0678] <Fused silica>

[0679] CAB-O-SIL TS-720 (manufactured by CABOT, fumed silica surface-treated with polydimethylsiloxane),

[0680]

[0681]

[0682] As shown in Table 8, the two-component curable resin compositions of Examples C1-12, which contain components (A) to (B) in the first component and components (G) and (D) in the second component, have short curing times and excellent curability.

[0683] In particular, it is known that for the two-component curable resin compositions of Examples C1, 2, 7-12 that use (G) components that do not have substituents other than phenolic hydroxyl groups on the aromatic ring, the resulting cured products have high shear bond strength and excellent adhesion.

[0684] Furthermore, it is known that for the two-component curable resin compositions of Examples C9-10 containing an epoxy silane coupling agent as component (F), the resulting cured products exhibit particularly high shear bond strength and excellent adhesion.

[0685] On the other hand, as shown in Table 9, for the two-component curable resin compositions that do not contain component (G), Comparative Example C1, which contains a compound having two phenolic hydroxyl groups and two tertiary alkyl groups in the ortho position, and Comparative Examples C3 to 6 which contain a compound having one phenolic hydroxyl group, the curing time is long and the curing performance is poor.

[0686]

[0687]

[0688] As shown in Table 11, for the two-component curable resin compositions of Examples C14-19, which contain components (A) to (B) in the first component and components (G) and (D) in the second component, the cured products have good shear bond strength.

[0689] It should be noted that, compared with the two-component curable resin composition of Example C14 with a molar ratio of 1.0, the cured products of the two-component curable resin compositions of Examples C15 to C17 with a molar ratio in the range of 1.1 to 1.6 exhibit very high shear bond strength, and the two-component curable resin compositions with a molar ratio of 1.1 to 1.6 have particularly excellent adhesive properties.

[0690] Furthermore, it is known that for the two-component curable resin compositions of Examples C18-19 containing an epoxy silane coupling agent as component (F), the resulting cured products exhibit particularly high shear bond strength and excellent adhesion.

[0691]

[0692] As shown in Table 12, for the two-component curable resin compositions of Examples C20 to 23, which contain components (A), (B) and (G) in the first component and components (G) and (D) or components (D) in the second component, the cured products have good shear bond strength.

[0693] On the other hand, compared with the two-component curable resin compositions of Examples C20-23, the two-component curable resin composition of Comparative Example C7, which does not contain component (G) in either the first or second component, (i) has a very long curing time and (ii) exhibits a very low shear bond strength.

[0694] It should be noted that components other than component (G) (e.g., components (D), (E), (F), and inorganic fillers other than (E)) have essentially no effect on the curing time. Therefore, the two-component curable resin compositions of Examples C13-23 show a high probability of having curing times similar to those of Examples C1 or 2, and at least shorter curing times than the two-component curable resin compositions of Comparative Examples C1-7.

[0695] Industrial applicability

[0696] According to one aspect of the present invention, as a two-component or multi-component epoxy resin composition, a new curable resin composition superior to those of the past can be provided. For example, according to a first embodiment, a two-component curable resin composition capable of producing a cured product exhibiting excellent thermal conductivity, flame retardancy, adhesive strength, and impact peel adhesion, and capable of curing at low temperatures at or near room temperature, can be provided. For example, according to a second embodiment, a two-component curable resin composition capable of producing a cured product exhibiting excellent thermal conductivity, flame retardancy, and adhesive strength, low viscosity, good workability, and capable of curing at low temperatures at or near room temperature, can be provided. For example, according to a third embodiment, a two-component or multi-component curable resin composition with excellent rapid curing properties can be provided. Therefore, the curable resin composition of one embodiment of the present invention can be preferably used as an adhesive suitable for structural applications in vehicles and aircraft, adhesives for secondary batteries such as EV battery cells, adhesives for structural applications in wind power generation, coatings, materials for laminating with glass fibers and / or carbon fibers to obtain composite materials, materials for printed wiring substrates, solder resists, interlayer insulating films, buildup materials, adhesives for FPCs, electrical insulating materials such as sealing materials for electronic components such as semiconductors / LEDs, chip bonding materials, underlayer fillers, mounting materials for semiconductors (e.g., ACF, ACP, NCF, NCP, etc.), sealing materials for display devices (e.g., liquid crystal panels and OLED displays, etc.) and lighting devices (e.g., OLED lighting, etc.), composite materials for concrete repair, etc., and is particularly preferably used as an adhesive for secondary batteries.

Claims

1. A curable resin composition which is a two-component type curable resin composition, the curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), the curable resin composition further containing a polymer particle (B) having a core-shell structure comprising a core layer and a shell layer, and aluminum hydroxide (C), the total weight of the aluminum hydroxide (C) in the total weight 100% of the curable resin composition being 55% by weight or more and 85% by weight or less, the average particle diameter of the aluminum hydroxide (C) being 11 μm or more and 200 μm or less, the content of the aluminum hydroxide (C) being 250 parts by weight or more and 750 parts by weight or less with respect to 100 parts by weight of the epoxy resin (A).

2. The curable resin composition according to claim 1, a cured product of which, when cured, shows a flame retardancy of V-0, V-l or V-2 in a vertical burning test of UL-94.

3. The curable resin composition according to claim 1, wherein the average particle diameter of the polymer particle (B) is 0.15 μm or more and 0.30 μm or less, the ratio of the weight of the core layer to the weight of the shell layer (the weight of the core layer / the weight of the shell layer) in the polymer particle (B) is 65 / 35 to 92 / 8, the shell layer of the polymer particle (B) is a copolymer obtained by polymerizing a monomer component, wherein, with respect to 100% by weight of the monomer component, (1) the content of an alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms is 55% by weight or more; and (2) the content of an alkyl ester of (meth)acrylic acid having 1 carbon atom is 10 to 100% by weight; and (3) the content of an alkyl ester of (meth)acrylic acid having 4 carbon atoms is 0 to 80% by weight.

4. The curable resin composition according to claim 1 or 2, wherein the epoxy curing agent (D) is one or more selected from the group consisting of aliphatic amines, alicyclic amines, amido amines, terminal amino polyethers, terminal amino nitrile rubbers, modified products of aliphatic amines, modified products of alicyclic amines, modified products of amido amines, modified products of terminal amino polyethers, and modified products of terminal amino nitrile rubbers.

5. The curable resin composition according to claim 1 or 2, wherein the curable resin composition further contains a compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, in the compound (G), the number of tertiary alkyl groups located at the ortho position of the phenolic hydroxyl groups is 0 or 1 per molecule, the epoxy curing agent (D) is at least one or more selected from the group consisting of aliphatic amines, alicyclic amines, amido amines, terminal amino polyethers, terminal amino nitrile rubbers, modified products of aliphatic amines, modified products of alicyclic amines, modified products of amido amines, modified products of terminal amino polyethers, and modified products of terminal amino nitrile rubbers.

6. The curable resin composition according to claim 1 or 2, wherein The ratio of the number of moles of the epoxy group possessed by the epoxy resin (A) to the number of moles of the active hydrogen group possessed by the epoxy curing agent (D) (the number of moles of the epoxy group possessed by the epoxy resin (A) / the number of moles of the active hydrogen group possessed by the epoxy curing agent (D)) is 0.5 or greater and 1.5 or less.

7. The curable resin composition according to claim 1 or 2, wherein The polymer particles (B) have diene-based rubber in the core layer, and the diene-based rubber is butadiene rubber and / or styrene-butadiene rubber.

8. The curable resin composition according to claim 1 or 2, wherein The polymer particles (B) having the core-shell structure have an epoxy group in the shell layer.

9. The curable resin composition according to claim 1 or 2, wherein The polymer particles (B) have an epoxy group in the shell layer, and the content of the epoxy group possessed by the shell layer is 0.1 to 2.0 mmol / g with respect to the total amount of the shell layer.

10. The curable resin composition according to claim 1 or 2, wherein The polymer particles (B) do not have an epoxy group in the shell layer.

11. A cured product, which is obtained by curing the curable resin composition according to any one of claims 1 to 10.

12. An adhesive, which comprises the curable resin composition according to any one of claims 1 to 10.

13. The adhesive according to claim 12, wherein The adhesive is an adhesive for secondary batteries.

14. A laminate, which comprises two substrates and an adhesive layer obtained by curing the adhesive according to claim 13, The adhesive layer bonds the two substrates together.

15. A curable resin composition, which is a two-component curable resin composition, The curable resin composition comprises a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), The curable resin composition further contains polymer particles (B) having a core-shell structure comprising a core layer and a shell layer, and aluminum hydroxide (C), The total weight of the aluminum hydroxide (C) in 100% by weight of the total weight of the curable resin composition is 55% by weight or greater and 85% by weight or less, The average particle diameter of the polymer particles (B) is 0.18 μm or greater and 0.30 μm or less, The ratio of the weight of the core layer to the weight of the shell layer (the weight of the core layer / the weight of the shell layer) in the polymer particles (B) is 65 / 35 to 92 / 8, The shell layer of the polymer particles (B) is a copolymer obtained by polymerizing the following monomer components, wherein with respect to 100% by weight of the monomer components, (1) the content of alkyl ester of (meth)acrylic acid having 1 to 4 carbon atoms is 55% by weight or greater; and (2) the content of alkyl ester of (meth)acrylic acid having 1 carbon atom is 10 to 100% by weight; and (3) the content of alkyl ester of (meth)acrylic acid having 4 carbon atoms is 0 to 80% by weight.

16. A curable resin composition which is a two-component or multi-component curable resin composition, the curable resin composition comprising a first component containing an epoxy resin (A) and a second component containing an epoxy curing agent (D), the curable resin composition further containing a polymer particle (B) having a core-shell structure comprising a core layer and a shell layer, and a compound (G) having (i) one aromatic ring and (ii) at least two phenolic hydroxyl groups in one molecule, in the compound (G), the number of tertiary alkyl groups located at the ortho position of the phenolic hydroxyl groups is zero or one per molecule, the epoxy curing agent (D) is at least one or more selected from the group consisting of aliphatic amines, alicyclic amines, amide amines, terminal amino polyethers, terminal amino nitrile rubbers, modified products of aliphatic amines, modified products of alicyclic amines, modified products of amide amines, modified products of terminal amino polyethers, and modified products of terminal amino nitrile rubbers, wherein, 4 to 25 parts by weight of the compound (G) is contained with respect to 100 parts by weight of the epoxy resin (A); or the compound (G) is one or more selected from the group consisting of resorcinol, catechol, hydroquinone, methylhydroquinone, tert-butylhydroquinone, chlorohydroquinone, 2,5-dichlorohydroquinone, and 2,5-dibromohydroquinone.

Images