Curable resin compositions and adhesives

Abstract

The present invention addresses the problem of providing a curable resin composition that achieves both vibration-damping properties and rigidity at high temperature. A curable resin composition according to the present invention contains an epoxy resin (A) and crosslinked polymer particles (B) having a specific structure.

Description

Technical Field

[0001] The present invention relates to a curable resin composition and an adhesive containing the same.

Background Art

[0002] Measures against vehicle noise and vibration have been conventionally important characteristics in vehicle body design. Noise that propagates through air via partitions and gaps has been addressed by installing various soundproofing materials, sound-absorbing materials, and noise-blocking materials. In addition, noise and vibration that propagate from drive systems such as engines, tires, and transmissions through various parts of the vehicle body have been solved by using vibration damping materials such as asphalt sheets. However, these additional parts are a problem in that they lead to an increase in vehicle body weight. There is a need for a method of controlling vehicle noise and vibration while suppressing an increase in vehicle body weight.

[0003] In Patent Document 1 and the like, studies have been made to apply a high elastic modulus epoxy-based structural adhesive to a vehicle body structure such as a center pillar to reduce the vehicle body weight. Further, Patent Document 2 discloses a technique for improving the damping property of vehicle body vibration without increasing the vehicle body weight by using an epoxy-based one-component thermosetting adhesive composition having a high elastic modulus and excellent vibration damping properties.

[0004] Patent Document 3 discloses a technique for improving the toughness and impact resistance of a cured product by dispersing polymer fine particles in a curable resin composition mainly composed of a curable resin such as an epoxy resin.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

[0006] Conventional one-component thermosetting adhesive compositions, such as those described in Patent Document 2, include compounding agents (such as dimer acid-modified epoxy and rubber-modified epoxy) that reduce the heat resistance (Tg) of the epoxy resin in order to improve the damping of vehicle body vibrations at or near room temperature. Therefore, in conventional one-component thermosetting adhesive compositions, such as those described in Patent Document 2, the inherently high elastic modulus (rigidity) of the epoxy resin may decrease significantly at high temperatures. In the case of automobiles, heat resistance of 80°C or higher is required.

[0007] One embodiment of the present invention aims to provide an epoxy-based curable resin composition that can provide a cured product that maintains a high modulus of elasticity even at high temperatures and exhibits excellent vibration damping properties, in view of the above-mentioned circumstances. [Means for solving the problem]

[0008] The inventors diligently conducted research to solve the above problems. As a result, the inventors have made the following novel discoveries and completed the present invention: an epoxy-based curable resin composition comprising a curable resin composition containing epoxy resin (A) and crosslinked polymer particles (B) having a specific composition can provide a cured product that maintains a high elastic modulus even at high temperatures and exhibits excellent vibration damping properties.

[0009] That is, a curable resin composition according to one embodiment of the present invention is a curable resin composition containing 100 parts by weight of epoxy resin (A) and 1 to 100 parts by weight of crosslinked polymer particles (B), wherein the crosslinked polymer particles (B) include one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3) described in (1) to (3) below; (1) The crosslinked polymer particles (B-1) have a core-shell structure and / or a monolayer structure including a core layer and a shell layer, the core layer and / or the monolayer is formed by polymerizing a monomer mixture (m-1) containing 0.1% to 10% by weight of a crosslinkable monomer, and contains a (meth)acrylate polymer (M-1) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and contains 60% by weight or more of (M-1) relative to the total amount of (B-1), the shell layer contains a (meth)acrylate polymer (M-1') formed by graft polymerization of the monomer mixture (m-1') onto the core layer, (2) The crosslinked polymer particles (B-2) have a core-shell structure comprising a core layer and a shell layer, wherein the core layer comprises a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) that does not contain crosslinkable monomers, and having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the shell layer comprises a (meth)acrylate polymer (M-2') obtained by graft polymerization of a monomer mixture (m-2') containing 1% to 100% by weight of crosslinkable monomers onto the core layer. (3) The crosslinked polymer particles (B-3) have a core-shell structure including a core layer and a shell layer, the shell layer contains a (meth)acrylate polymer (M-3') having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the content of the shell layer relative to the total amount of the crosslinked polymer particles (B-3) is 30% to 90% by weight. [Effects of the Invention]

[0010] The curable resin composition according to one embodiment of the present invention, configured as described above, comprises an epoxy resin and crosslinked polymer particles having a specific composition. Therefore, the cured product obtained from this curable resin composition exhibits the effect of maintaining a high modulus of elasticity even at high temperatures and showing excellent vibration damping properties. [Modes for carrying out the invention]

[0011] One or more embodiments of the present invention will be described below, but the present invention is not limited to the embodiments described below. The present invention is not limited to the configurations described below, and various modifications are possible within the scope of the claims, and embodiments and examples obtained by appropriately combining the technical means disclosed in different embodiments and examples are also included in the technical scope of the present invention. Furthermore, all academic and patent documents mentioned herein are incorporated herein by reference. Furthermore, unless otherwise specified herein, "A~B" representing a numerical range is intended to mean "A or more and B or less".

[0012] In this specification, "weight" is synonymous with "mass" and is intended to mean "mass." Therefore, "weight" may be replaced with "mass" in this specification.

[0013] [1. Technical Concept of One Embodiment of an Embodiment] The cured product obtained by curing the curable adhesive composition disclosed in Patent Document 2 exhibits a good elastic modulus at room temperature, but the elastic modulus decreases at high temperatures, and the rigidity at high temperatures is sometimes insufficient. This is thought to be because the non-crosslinked elastomers, such as dimer acid-modified epoxy resin and CTBN-modified epoxy resin, used as damping components in Patent Document 2, remain partially or completely miscible in the epoxy resin even after curing of the curable adhesive composition, thereby lowering the high glass transition temperature, which is a characteristic of epoxy resins. For example, in the case of automobiles, heat resistance of 80°C or higher is required, assuming summer conditions. The inventors of the present invention have diligently conducted research with the aim of providing a cured product that has excellent rigidity and vibration damping at room temperature, and whose rigidity does not easily decrease at high temperatures (its elastic modulus does not easily decrease at high temperatures).

[0014] The inventors have newly discovered that crosslinked polymer particles do not dissolve in the epoxy resin after curing, and do not significantly reduce the heat resistance of the cured epoxy resin product. Based on this finding, the inventors considered introducing a damping polymer component into the crosslinked polymer particles to achieve both rigidity and damping at high temperatures and conducted diligent research. As a result, the inventors have newly discovered that a curable resin composition containing crosslinked polymer particles containing a (meth)acrylate polymer (hereinafter also referred to as "damping polymer") having a glass transition temperature of -20°C to 30°C exhibits high damping at around room temperature in the cured product. The inventors have also newly discovered that the lower the degree of crosslinking of the "damping polymer" (the fewer crosslinkable monomers constituting the damping polymer), the better the damping performance. Furthermore, the inventors have also newly discovered that the higher the content of the "damping polymer," the better the damping performance. Based on this, the inventors have completed the present invention by designing crosslinked polymer particles with the following three compositions (1) to (3) as crosslinked polymer particles containing the damping polymer, thereby providing a curable resin composition that achieves both rigidity and damping at high temperatures.

[0015] (1) The crosslinked polymer particle (B-1) is a crosslinked polymer particle with a core-shell structure in which the core layer contains a low-crosslinking damping polymer (containing 0.1% to 10% by weight of crosslinkable monomers) at an amount of 60% to 100% by weight relative to (B-1), and the shell layer contains a (meth)acrylate-based polymer. Note that (B-1) can also be a single-layer crosslinked polymer particle consisting only of the low-crosslinking damping polymer (100% by weight of the low-crosslinking damping polymer).

[0016] (2) Crosslinked polymer particles (B-2) are crosslinked polymer particles with a core-shell structure, in which the core layer contains a non-crosslinked (no crosslinkable monomers) damping polymer and the shell layer contains a low-crosslinked to high-crosslinked (meth)acrylate polymer (containing 1% to 100% by weight of crosslinkable monomers).

[0017] (3) Crosslinked polymer particles (B-3) are crosslinked polymer particles with a core-shell structure in which the shell layer contains 30% to 90% by weight of a damping polymer.

[0018] There has been no report so far on a curable resin composition that can provide a cured product excellent in vibration damping properties and also in rigidity at high temperatures, which can be said to be a surprising discovery. Such a curable resin composition is extremely useful as an adhesive, particularly as a damping adhesive.

[0019] In addition, the present inventors have newly found that the curable resin composition according to one embodiment of the present invention can provide a cured product excellent in vibration damping properties and rigidity at high temperatures, and also has excellent adhesiveness. Conventional damping adhesives such as those described in Patent Document 2 have low adhesiveness, and from this point as well, the curable resin composition according to one embodiment of the present invention is extremely useful as a damping adhesive.

[0020] 〔2. Curable resin composition〕 A curable resin composition according to one embodiment of the present invention (hereinafter, the "curable resin composition according to one embodiment of the present invention" may be referred to as "the present curable resin composition") is a curable resin composition containing 100 parts by weight of an epoxy resin (A) and 1 to 100 parts by weight of crosslinked polymer particles (B), wherein the crosslinked polymer particles (B) contain one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3) described in the following (1) to (3); (1) The crosslinked polymer particles (B-1) have a core-shell structure or a single-layer structure including a core layer and a shell layer, and the core layer and / or the single layer contain a (meth)acrylate-based polymer (M-1) obtained by polymerizing a monomer mixture (m-1) containing 0.1% by weight or more and 10% by weight or less of a crosslinkable monomer, and having a glass transition temperature of -20°C or higher and 30°C or lower determined by the Fox formula, and contain (M-1) in an amount of 60% by weight or more based on the total amount of (B-1), and the shell layer contains a (meth)acrylate-based polymer (M-1') obtained by graft-polymerizing a monomer mixture (m-1') onto the core layer. (2) The crosslinked polymer particles (B-2) have a core-shell structure including a core layer and a shell layer. The core layer contains a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) that does not contain a crosslinkable monomer, and has a glass transition temperature of -20°C or higher and 30°C or lower determined by the Fox equation. The shell layer contains a (meth)acrylate polymer (M-2’) obtained by graft-polymerizing a monomer mixture (m-2’) containing 1 wt% or more and 100 wt% or less of a crosslinkable monomer onto the core layer. (3) The crosslinked polymer particles (B-3) have a core-shell structure including a core layer and a shell layer. The shell layer contains a (meth)acrylate polymer (M-3’) having a glass transition temperature of -20°C or higher and 30°C or lower determined by the Fox equation, and the content of the shell layer with respect to the total amount of the crosslinked polymer particles (B-3) is 30 wt% or more and 90 wt% or less.

[0021] Since the curable resin composition has the above configuration, it can provide a cured product that maintains a high elastic modulus even at high temperatures and exhibits excellent vibration damping properties. The cured product can be obtained by curing the curable resin composition by a known method. When the curable resin composition is used as an adhesive, the cured product can also be referred to as an "adhesive layer".

[0022] Hereinafter, "epoxy resin (A)" and "crosslinked polymer particles (B)" may be represented as "(A) component" and "(B) component", respectively.

[0023] <Epoxy resin (A)> The curable resin composition of one embodiment of the present invention contains an epoxy resin (A) as the curable resin. Various epoxy resins can be used as the epoxy resin. Examples of epoxy resins 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, novolac type epoxy resin, glycidyl ether type epoxy resin of bisphenol A propylene oxide adduct, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, fluorinated epoxy resin, flame-retardant epoxy resins such as glycidyl ether of tetrabromobisphenol A, p-oxybenzoic acid glycidyl ether type epoxy resin, m-aminophenol type epoxy resin, diaminodiphenylmethane-based epoxy resin, various alicyclic epoxy resins, N, Examples of epoxy resins include N-diglycidylaniline, N,N-diglycidyl-o-toluidine, triglycidyl isocyanurate, divinylbenzene dioxide, resorcinol diglycidyl ether, polyalkylene glycol diglycidyl ether, glycol diglycidyl ether, diglycidyl ester of aliphatic polybasic acid, glycidyl ether of divalent or higher polyhydric aliphatic alcohol such as glycerin, chelate-modified epoxy resins, rubber-modified epoxy resins, urethane-modified epoxy resins, hydantoin-type epoxy resins, epoxidized compounds of unsaturated polymers such as petroleum resins, aminoglycidyl ether resins, and epoxy compounds obtained by adding bisphenol A (or F) compounds or polybasic acids to the above epoxy resins. The epoxy resin is not limited to these examples, and commonly used epoxy resins may be used. These epoxy resins may be used individually or in combination of two or more.

[0024] Of these, the polyalkylene glycol diglycidyl ether can be more specifically identified as polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and the like. The glycol diglycidyl ether can be more specifically identified as neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, and the like. The aliphatic polybasic acid diglycidyl ester can be more specifically identified as dimer acid diglycidyl ester, adipic acid diglycidyl ester, sebacate acid diglycidyl ester, maleic acid diglycidyl ester, and the like. The diglycidyl ether of divalent or higher polyhydric aliphatic alcohol can be more specifically identified as trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, castor oil modified polyglycidyl ether, propoxylated glycerin triglycidyl ether, sorbitol polyglycidyl ether, and the like.

[0025] The polyalkylene glycol diglycidyl ether, the glycol diglycidyl ether, the diglycidyl ester of the aliphatic polybasic acid, and the glycidyl ether of the divalent or higher polyhydric aliphatic alcohol are epoxy resins having relatively low viscosity. These epoxy resins having relatively low viscosity are sometimes referred to as "polyepoxides." When polyepoxides are used in combination with other epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins, the polyepoxides function as reactive diluents, improving the balance between the viscosity of the composition and the physical properties of the cured product. That is, it is preferable that the epoxy resin (A) contains polyepoxides as a reactive diluent. On the other hand, monoepoxides function as reactive diluents as described later, but are not included in epoxy resin (A). The content of these epoxy resins that function as reactive diluents (e.g., polyepoxides) is preferably 0.5% to 30% by weight, more preferably 2% to 20% by weight, and even more preferably 5% to 15% by weight, based on 100% by weight of component (A).

[0026] The chelate-modified epoxy resin is a reaction product of an epoxy resin and a compound containing a chelate functional group (chelate ligand). When a curable resin composition contains a chelate-modified epoxy resin, the adhesion (adhesion strength) to the surface of a metal substrate contaminated with an oily substance can be improved, making it a particularly suitable curable resin composition for use as an adhesive for vehicle components. A chelate functional group is a functional group of a compound that has multiple coordination sites in its molecule capable of coordinating to metal ions. Examples include phosphorus-containing acid groups (e.g., -PO(OH)2), carboxylic acid groups (-CO2H), sulfur-containing acid groups (e.g., -SO3H), amino groups, and hydroxyl groups (especially hydroxyl groups adjacent to each other in an aromatic ring). Examples of chelate ligands include ethylenediamine, bipyridine, ethylenediaminetetraacetic acid, phenanthroline, porphyrin, and crown ether. Commercially available chelate-modified epoxy resins can also be used as the chelate-modified epoxy resin. Examples of commercially available chelate-modified epoxy resins include ADEKA's Adeka Resin EP-49-10N. The amount (content) of chelate-modified epoxy resin used in 100% by weight of component (A) is preferably 0.1% to 10% by weight, more preferably 0.5% to 3% by weight.

[0027] Examples of epoxy compounds obtained by adding polybasic acids to epoxy resins include the addition reaction product of a tall oil fatty acid dimer (dimer acid) and a bisphenol A type epoxy resin (dimer acid-modified epoxy resin), as described in International Publication No. 2010-098950. From the viewpoint of the heat resistance of the resulting cured product, the amount (content) of dimer acid-modified epoxy resin used is preferably 60% by weight or less, more preferably 50% by weight or less, and even more preferably 40% by weight or less, out of 100% by weight of component (A).

[0028] The rubber-modified epoxy resin is intended to be a reaction product obtained by reacting rubber with an epoxy group-containing compound. The rubber-modified epoxy resin preferably has 1.1 or more epoxy groups per molecule on average, and more preferably 2 or more. Examples of rubber include rubber polymers such as acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), hydrogenated nitrile rubber (HNBR), carboxyl-terminated NBR (CTBN), ethylene propylene rubber (EPDM), acrylic rubber (ACM), butyl rubber (IIR), butadiene rubber, and polyoxyalkylenes such as polypropylene oxide, polyethylene oxide, and polytetramethylene oxide. The rubber polymer preferably has reactive groups such as amino groups, hydroxyl groups, or carboxyl groups at its ends. The rubber-modified epoxy resin is a reaction product obtained by reacting these rubber polymers with epoxy resins in appropriate blending ratios using known methods. Among rubber-modified epoxy resins, acrylonitrile-butadiene rubber-modified epoxy resins and polyoxyalkylene-modified epoxy resins are preferred from the viewpoint of the adhesion (adhesive strength) and impact resistance of the resulting curable resin composition, with acrylonitrile-butadiene rubber-modified epoxy resins being more preferred. Acrylonitrile-butadiene rubber-modified epoxy resins can be obtained, for example, by the reaction of carboxyl-terminated NBR (CTBN) with a bisphenol A type epoxy resin.

[0029] In the 100% by weight acrylonitrile-butadiene rubber-modified epoxy resin, the content of constituent components derived from acrylonitrile monomers in the acrylonitrile-butadiene rubber is (i) 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 adhesion (adhesive strength) and impact resistance of the resulting curable resin composition, and (ii) particularly preferably 20% to 30% by weight, from the viewpoint of the workability of the resulting curable resin composition.

[0030] Furthermore, the workability of a curable resin composition can be evaluated, for example, by its viscosity. For instance, if the viscosity of a curable resin composition is low, it can be said that the composition has excellent workability.

[0031] Furthermore, for example, the addition reaction product of an amino-terminated polyoxyalkylene and an epoxy resin (hereinafter also referred to as the "adduct") is also included in rubber-modified epoxy resins. The addition reaction product can be easily manufactured by known methods, for example, as described in U.S. Patent No. 5084532 and U.S. Patent No. 6015865. The epoxy resin used in manufacturing the addition reaction product can be, for example, a specific example of component (A) mentioned above, but bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferred, and bisphenol A type epoxy resin is more preferred. Examples of commercially available amino-terminated polyoxyalkylenes used in manufacturing the addition reaction product include Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, and Jeffamine T-5000 from Huntsman.

[0032] The average number of epoxide-reactive end groups per molecule in the rubber is preferably 1.5 to 2.5, and more preferably 1.8 to 2.2. The number-average molecular weight of the rubber, measured by gel permeation chromatography (GPC) in terms of polystyrene-equivalent molecular weight, is preferably 1000 to 10000, more preferably 2000 to 8000, and particularly preferably 3000 to 6000. This configuration has the advantage that the resulting curable resin composition has excellent adhesion (adhesion strength) and workability.

[0033] There are no particular restrictions on the method for producing rubber-modified epoxy resins. For example, they can be produced by reacting rubber with an epoxy group-containing compound in a large amount of epoxy group-containing compound. Specifically, it is preferable to react at least two equivalents of epoxy group-containing compound per equivalent of epoxy-reactive end groups in the rubber. It is even more preferable to react the rubber with an amount of epoxy group-containing compound sufficient to produce an adduct of rubber and the epoxy group-containing compound, and a mixture of free epoxy group-containing compound. For example, rubber-modified epoxy resins can be produced by heating a mixture of the epoxy group-containing compound and rubber at a temperature of 100°C to 250°C in the presence of a catalyst such as phenyldimethylurea and triphenylphosphine. There are no particular restrictions on the epoxy group-containing compound used in the production of rubber-modified epoxy resins, but bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred, with bisphenol A type epoxy resins being more preferred. Note that if an excess amount of epoxy group-containing compound is used in the production of rubber-modified epoxy resins, unreacted epoxy group-containing compound may remain in the reaction product obtained after the reaction. Any unreacted epoxy group-containing compounds remaining in this manner are not included in the rubber-modified epoxy resin as defined herein.

[0034] In rubber-modified epoxy resins, the rubber-modified epoxy resin can be modified by pre-reacting it with a bisphenol component. The amount of bisphenol component used for modification is preferably 3 to 35 parts by weight, and more preferably 5 to 25 parts by weight, per 100 parts by weight of the rubber component in the rubber-modified epoxy resin. The cured product obtained by curing a curable resin composition containing the modified rubber-modified epoxy resin exhibits excellent adhesive durability after exposure to high temperatures, as well as excellent impact resistance at low temperatures.

[0035] The glass transition temperature (Tg) of the rubber-modified epoxy resin is not particularly limited, but is preferably -25°C or lower, more preferably -35°C or lower, even more preferably -40°C or lower, and particularly preferably -50°C or lower.

[0036] The number-average molecular weight of the rubber-modified epoxy resin is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000, as measured by GPC in terms of polystyrene-equivalent molecular weight. This configuration has the advantage that the resulting curable resin composition has excellent adhesion (adhesion strength) and workability. The molecular weight distribution of the rubber-modified epoxy resin (ratio of weight-average molecular weight to number-average molecular weight (weight-average molecular weight / number-average molecular weight)) is preferably 1.0 to 4.0, more preferably 1.2 to 3.0, and particularly preferably 1.5 to 2.5. This configuration has the advantage that the resulting curable resin composition has excellent workability.

[0037] Rubber-modified epoxy resins can be used individually or in combination of two or more types.

[0038] When using rubber-modified epoxy resin, the amount (content) of rubber-modified epoxy resin in 100% by weight of component (A) is preferably 1% to 50% by weight, more preferably 2% to 40% by weight, even more preferably 5% to 30% by weight, and particularly preferably 10% to 20% by weight.

[0039] The urethane-modified epoxy resin is a reaction product obtained by reacting a compound containing a group that is reactive with isocyanate groups and epoxy groups with a urethane prepolymer containing isocyanate groups. The urethane-modified epoxy resin preferably has 1.1 or more epoxy groups per molecule on average, and more preferably 2 or more. For example, a urethane-modified epoxy resin can be obtained by reacting a hydroxyl group-containing epoxy compound with a urethane prepolymer.

[0040] The number-average molecular weight of the urethane-modified epoxy resin is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000, as measured by GPC in terms of polystyrene-equivalent molecular weight. This configuration has the advantage that the resulting curable resin composition has excellent adhesion (adhesion strength) and workability. The molecular weight distribution of the urethane-modified epoxy resin (ratio of weight-average molecular weight to number-average molecular weight (weight-average molecular weight / number-average molecular weight)) is preferably 1.0 to 4.0, more preferably 1.2 to 3.0, and particularly preferably 1.5 to 2.5. This configuration has the advantage that the resulting curable resin composition has excellent workability.

[0041] Urethane-modified epoxy resins can be used individually or in combination of two or more types.

[0042] When using urethane-modified epoxy resin, the amount (content) of urethane-modified epoxy resin in 100% by weight of component (A) is preferably 1% to 50% by weight, more preferably 2% to 40% by weight, even more preferably 5% to 30% by weight, and particularly preferably 10% to 20% by weight.

[0043] The total amount of dimer acid-modified epoxy resin, rubber-modified epoxy resin, and urethane-modified epoxy resin is preferably 70% by weight or less, more preferably 60% by weight or less, even more preferably 50% by weight or less, and particularly preferably 40% by weight or less, based on 100% by weight of component (A), from the viewpoint of the heat resistance of the resulting cured product.

[0044] Among these epoxy resins, epoxy resins having at least two epoxy groups in one molecule are preferred because they have high curability, the cured product is highly flexible, and they are excellent at improving impact peel resistance through the incorporation of cross-linked polymer particles (B). As epoxy resin (A), compounds (epoxy resins) having two epoxy groups in one molecule are particularly preferred.

[0045] Furthermore, when using an epoxy resin (A) with a small epoxy equivalent value among various epoxy resins, the resulting cured product has the advantage of high elastic modulus and heat resistance. For this reason, epoxy resin (A) preferably contains epoxy resin (A1) with an epoxy equivalent of 90 g / eq or more and less than 200 g / eq, more preferably 100 g / eq or more and less than 195 g / eq, even more preferably 120 g / eq or more and less than 191 g / eq, and particularly preferably 150 g / eq or more and less than 190 g / eq. In this specification, "epoxy resin (A1)" may also be referred to as "component (A1)".

[0046] The content of epoxy resin (A1) in the total amount of epoxy resin (A) in this curable resin composition, in other words, the content of epoxy resin (A1) in 100% by weight of epoxy resin (A), will be explained. From the viewpoint of the elastic modulus and heat resistance of the resulting cured product, the content is preferably 25% by weight or more, more preferably 40% by weight or more, even more preferably 50% by weight or more, and particularly preferably 60% by weight or more.

[0047] In this specification, epoxy equivalent refers to the molecular weight per epoxy group in a compound containing epoxy groups, and specifically, is a value calculated based on the following formula: Epoxy equivalent (g / eq) = Mass-average molecular weight (Mw) of the compound / Number of epoxy groups per molecule of the compound (average number). Furthermore, epoxy equivalent can also be measured in accordance with JIS K7236.

[0048] Furthermore, when using an epoxy resin (A) with a small number-average molecular weight among various epoxy resins, the resulting cured product has the advantage of high elastic modulus and heat resistance. For this reason, the number-average molecular weight of epoxy resin (A) is preferably 180 or more and less than 400, and more preferably 300 or more and less than 390.

[0049] When using bisphenol A type epoxy resin and / or bisphenol F type epoxy resin as epoxy resin (A), the resulting cured product has the advantages of high elastic modulus, excellent heat resistance and adhesion (adhesion strength), and relatively low cost. Therefore, epoxy resin (A) preferably contains bisphenol A type epoxy resin (A2) and / or bisphenol F type epoxy resin (A2), and is particularly preferably bisphenol A type epoxy resin (A2). In this specification, "bisphenol A type epoxy resin (A2)" and "bisphenol F type epoxy resin (A2)" may also be referred to as "(A2) component".

[0050] This section describes the content of bisphenol A type epoxy resin (A2) and / or bisphenol F type epoxy resin (A2) in the total amount of epoxy resin (A) in this curable resin composition, in other words, the content of bisphenol A type epoxy resin (A2) and / or bisphenol F type epoxy resin (A2) in 100% by weight of epoxy resin (A) (total content). From the viewpoint of the elastic modulus and heat resistance of the resulting cured product, this content (total content) is preferably 25% by weight or more, more preferably 40% by weight or more, even more preferably 50% by weight or more, and particularly preferably 60% by weight or more.

[0051] For example, as an epoxy resin that is both component (A1) and component (A2), a bisphenol A type epoxy resin (A3) having an epoxy equivalent of 90 g / eq or more and less than 200 g / eq and / or a bisphenol F type epoxy resin (A3) having an epoxy equivalent of 90 g / eq or more and less than 200 g / eq may be used. Therefore, in this curable resin composition, the total amount of component (A1) and component (A2) is preferably 25% by weight or more, more preferably 40% by weight or more, even more preferably 50% by weight or more, and particularly preferably 60% by weight or more, out of 100% by weight of component (A), from the viewpoint of the elastic modulus and heat resistance of the resulting cured product.

[0052] In particular, bisphenol A type epoxy resins with an epoxy equivalent of less than 200 g / eq and bisphenol F type epoxy resins with an epoxy equivalent of less than 200 g / eq are preferred because they are liquid at room temperature and the resulting curable resin compositions are easy to handle.

[0053] Since the resulting cured product has excellent impact resistance, epoxy resin (A) preferably contains a bisphenol A type epoxy resin with an epoxy equivalent of 200 g / eq or more and less than 5000 g / eq and / or a bisphenol F type epoxy resin with an epoxy equivalent of 200 g / eq or more and less than 5000 g / eq, more preferably containing 40% by weight or less, and more preferably containing 20% ​​by weight or less, of 100% by weight of component (A).

[0054] <Cross-linked polymer particles (B)> The curable resin composition according to one embodiment of the present invention can provide a cured product with excellent vibration damping properties due to the damping improvement effect of component (B). Furthermore, the curable resin composition according to one embodiment of the present invention can provide a cured product with excellent toughness and adhesion, as well as high Tg, good heat resistance and elastic modulus (rigidity), due to the toughness improvement effect of component (B). The curable resin composition according to one embodiment of the present invention can provide a cured product with particularly good elastic modulus (rigidity) at high temperatures, as component (B) exhibits a toughness improvement effect without significantly reducing the heat resistance of the epoxy resin cured product.

[0055] A curable resin composition according to one embodiment of the present invention contains 1 to 100 parts by mass of crosslinked polymer particles (B) per 100 parts by mass of component (A). The curable resin composition preferably contains 3 to 70 parts by mass of component (B) per 100 parts by mass of component (A), more preferably 5 to 50 parts by mass, and even more preferably 10 to 40 parts by mass of component (B).

[0056] One embodiment of the present invention contains one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1) to (B-3) having specific compositions, each having the following configurations (1) to (3), and includes a (meth)acrylate-based polymer having a glass transition temperature (Tg) of -20°C to 30°C as a damping component (hereinafter also referred to as "damping polymer"). In one embodiment of the present invention, component (B) is more preferably one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1) to (B-3). This makes it possible to increase the damping properties without reducing the heat resistance of the epoxy resin. In this specification, (meth)acrylate means acrylate and / or methacrylate.

[0057] The glass transition temperature (Tg) of the (meth)acrylate polymer is calculated in Kelvin using the following FOX formula (Equation 1) and then converted to Celsius. From the viewpoint of vibration damping properties of the cured product, the glass transition temperature of the (meth)acrylate polymer (damping polymer) must be between -20°C and 30°C, preferably between -15°C and 25°C, more preferably between -10°C and 20°C, even more preferably between -5°C and 18°C, and particularly preferably between 0°C and 15°C. 1 / Tg = Σ(M i / Tg i (Equation 1) (In the formula, M i The weight fraction of monomer i component constituting the (meth)acrylate polymer, Tg i This represents the glass transition temperature (K) of the homopolymer of monomer i. The glass transition temperature of monomeric homopolymers can be confirmed from literature and catalogs such as "Polymer Handbook, Fourth Edition" by J. Brandrup.

[0058] <(1) Cross-linked polymer particles (B-1)> The crosslinked polymer particles (B-1) have a core-shell structure including a core layer and a shell layer, or a single-layer structure. Crosslinked polymer particles (B-1) may be a combination of crosslinked polymer particles having a core-shell structure and crosslinked polymer particles having a single-layer structure. The crosslinked polymer particles (B-1) are obtained by polymerizing a monomer mixture (m-1) containing 0.1% to 10% by weight of a crosslinkable monomer, and contain 60% to 100% by weight of a (meth)acrylate polymer (M-1) with a glass transition temperature of -20°C to 30°C as determined by the Fox formula, relative to the total amount of (B-1).

[0059] In the cross-linked polymer particles (B-1), the (meth)acrylate-based polymer (M-1) corresponds to the damping polymer described above.

[0060] In this specification, "crosslinked polymer particles having a core-shell structure including a core layer and a shell layer" may be referred to as "core-shell polymer" or "core-shell polymer particles." In this specification, "crosslinked polymer particles having a single-layer structure" may be referred to as "single-layer polymer" or "single-layer polymer particles."

[0061] The core layer and / or the single layer preferably include (M-1), and more preferably consist only of (M-1). In other words, the core layer and / or the single layer is more preferably formed of (M-1). In this specification, "X consists only of Y" can also be said to mean "X is Y".

[0062] If the core layer contains (M-1) or is formed by (M-1), then (M-1) is present in an amount of 60% by weight or more and less than 100% by weight relative to the total amount of (B-1).

[0063] The shell layer preferably contains a (meth)acrylate polymer (M-1') obtained by graft polymerization of a monomer mixture (m-1') onto the core layer, and more preferably consists only of (M-1'). The (meth)acrylate polymer (M-1') is not particularly limited, and those described in ((meth)acrylate polymer) below can be used. The (meth)acrylate polymer (M-1') preferably contains a (meth)acrylate polymer (M-1'-a) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and more preferably consists only of (M-1'-a). This configuration has the advantage that the cured product obtained by curing the resulting curable resin composition has superior vibration damping properties.

[0064] From the viewpoint of improving the vibration damping and adhesion of the cured product obtained by curing the curable resin composition, the epoxy group content in the (meth)acrylate polymer (M-1') is preferably 0.0 mmol / g or more and 2.0 mmol / g or less, more preferably 0.1 mmol / g or more and 1.0 mmol / g or less, and particularly preferably 0.2 mmol / g or more and 0.7 mmol / g or less, relative to the total amount of (M-1').

[0065] The statement that the epoxy group content in (M-1') is 0.0 mmol / g relative to the total amount of (M-1') means that (M-1') does not contain epoxy groups. (M-1') does not necessarily have to contain epoxy groups.

[0066] When the single layer in the crosslinked polymer particles having the aforementioned single-layer structure is formed by (M-1), the single-layer polymer (B-1) contains 100% by weight of (M-1) relative to the total amount of (B-1). That is, when the single layer is formed by (M-1), the single layer (B-1) is formed solely from (M-1).

[0067] The cross-linked polymer particles (B-1) may be single-layer cross-linked polymer particles composed solely of (meth)acrylate polymer (M-1). This configuration has the advantage of reducing the time required for the production of the cross-linked polymer particles (B-1) and improving productivity.

[0068] The cross-linked polymer particles (B-1) may be a combination of cross-linked polymer particles having a core-shell structure and cross-linked polymer particles having a single-layer structure. That is, the (meth)acrylate polymer (M-1) may be used in both the core layer of the core-shell structure and the single layer of the single-layer structure. Notwithstanding the limitations of the function (effect) of one embodiment of the present invention, the core layer of the core-shell polymer may have components other than (M-1), and the single layer of the single-layer polymer may have components other than (M-1). Furthermore, (B-1) may have components other than (M-1).

[0069] The content of component (M-1) in component (B-1) is 60% by weight or more of the total amount (100% by weight) of (B-1) when (B-1) is a crosslinked polymer particle having a core-shell structure. From the viewpoint of improving the vibration damping properties of the cured product obtained by curing the curable resin composition, the content of component (M-1) in the total amount (100% by weight) of component (B-1) is preferably 70% by weight or more, more preferably 75% by weight or more, even more preferably 80% by weight or more, and particularly preferably 85% by weight or more. The upper limit of the content of component (M-1) in the total amount (100% by weight) of component (B-1) is less than 100% by weight, but is preferably 99 parts by weight or less, more preferably 95 parts by weight or less, even more preferably 93 parts by weight or less, and particularly preferably 90 parts by weight or less. When (B-1) is a crosslinked polymer particle having a single-layer structure, the single-layer polymer (B-1) may have other components other than component (M-1) as described above, but it is preferable that it does not contain other components. In other words, if (B-1) is a cross-linked polymer particle having a single-layer structure, it is preferable that component (M-1) is 100% by weight of the total amount (100% by weight) of component (B-1), which is a single-layer polymer.

[0070] The content of the crosslinkable monomer in the monomer mixture (m-1) is 0.1% by weight or more and 10.0% by weight or less per 100% by weight of the monomer mixture (m-1), preferably 0.2% by weight or more and 8.0% by weight or less, more preferably 0.3% by weight or more and 7.0% by weight or less, even more preferably 0.4% by weight or more and 6.0% by weight or less, and particularly preferably 0.5% by weight or more and 5.0% by weight or less. By setting the content of the crosslinkable monomer in 100% by weight of the monomer mixture (m-1) to (a) 0.1% by weight or more, the storage stability of the curable resin composition due to swelling of component (B-1) can be improved, and by setting it to 10.0% by weight or less, the vibration damping properties of the cured product obtained by curing the curable resin composition can be improved.

[0071] As specific examples of crosslinkable monomers in (m-1), the crosslinkable monomers described in ((meth)acrylate polymers) below can be used.

[0072] <(2) Cross-linked polymer particles (B-2)> The crosslinked polymer particles (B-2) have a core-shell structure comprising a core layer and a shell layer. The core layer contains a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) that does not contain crosslinkable monomers (0.0 wt%), and has a glass transition temperature of -20°C to 30°C as determined by the Fox formula. The shell layer contains a (meth)acrylate polymer (M-2') obtained by graft polymerizing a monomer mixture (m-2') containing 1% to 100% by weight of crosslinkable monomers onto the core layer.

[0073] In the cross-linked polymer particles (B-2), the (meth)acrylate-based polymer (M-2) corresponds to the damping polymer described above.

[0074] The core layer of the crosslinked polymer particles (B-2) preferably contains (M-2), and more preferably consists solely of (M-2). In other words, the core layer of the crosslinked polymer particles (B-2) is more preferably formed of (M-2).

[0075] The case in which the core layer of the crosslinked polymer particle (B-2) is formed by (M-2) will be explained. By forming the core layer by polymerizing a monomer mixture (m-2) that does not contain crosslinkable monomers, the acrylate polymer (M-2) obtained immediately after polymerization, i.e., the core layer, does not have a crosslinked structure (it is not crosslinked). Then, by graft polymerization of the monomer mixture (m-2') containing crosslinkable monomers onto the non-crosslinked core layer, (B-2) becomes a polymer particle that has a crosslinked structure as a whole.

[0076] Furthermore, the core layer of the core-shell polymer may have components other than (M-2) as long as it does not impair the function (effect) of one embodiment of the present invention. Also, (B-2) may have components other than (M-2).

[0077] When the core layer of the crosslinked polymer particles (B-2) is formed by (M-2), the content of the (M-2) component, which is the core layer in the (B-2) component, is preferably 50 to 95 parts by weight, more preferably 60 to 95 parts by weight, more preferably 70 to 93 parts by weight, even more preferably 80 to 91 parts by weight, and particularly preferably 85 to 90 parts by weight, out of the total amount (100 parts by weight) of (B-2).

[0078] The content of the core layer in component (B-2) is preferably 50% to 95% by weight, more preferably 60% to 95% by weight, more preferably 70% to 93% by weight, even more preferably 80% to 91% by weight, and particularly preferably 85% to 90% by weight, based on the total amount (100% by weight) of (B-2).

[0079] The content of component (M-2) in component (B-2) is preferably 50% to 95% by weight, more preferably 60% to 95% by weight, more preferably 70% to 93% by weight, even more preferably 80% to 91% by weight, and particularly preferably 85% to 90% by weight, based on the total amount (100% by weight) of (B-2).

[0080] The shell layer of the crosslinked polymer particles (B-2) preferably contains a (meth)acrylate polymer (M-2') obtained by graft polymerization of a monomer mixture (m-2') onto the core layer, and more preferably consists solely of (M-2').

[0081] The (meth)acrylate polymer (M-2') is not particularly limited, and those described below under ((meth)acrylate polymer) can be used. The (meth)acrylate polymer (M-2') preferably contains a (meth)acrylate polymer (M-2'-a) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and more preferably consists only of (M-2'-a). This configuration has the advantage that the cured product obtained by curing the resulting curable resin composition has superior vibration damping properties.

[0082] The content of the crosslinkable monomer in the monomer mixture (m-2') is 1.0% by weight or more and 100% by weight or less per 100% by weight of the monomer mixture (m-2'), preferably 1.3% by weight or more and 80% by weight or less, more preferably 1.5% by weight or more and 60% by weight or less, even more preferably 1.7% by weight or more and 40% by weight or less, and particularly preferably 2.0% by weight or more and 20% by weight or less. By setting the content of the crosslinkable monomer in 100% by weight of the monomer mixture (m-2') to 1.0% by weight or more, the storage stability of the curable resin composition due to swelling of component (B-2) can be improved. That is, the crosslinked polymer particles (B-2) preferably have an uncrosslinked core layer and a shell layer having a predetermined degree of crosslinking, as described above.

[0083] Specific examples of crosslinkable monomers in (m-2') include the crosslinkable monomers described later under ((meth)acrylate polymers).

[0084] From the viewpoint of improving the vibration damping and adhesion of the cured product obtained by curing the curable resin composition, the epoxy group content in the (meth)acrylate polymer (M-2') is preferably 0.0 mmol / g or more and 2.0 mmol / g or less, more preferably 0.1 mmol / g or more and 1.0 mmol / g or less, and particularly preferably 0.2 mmol / g or more and 0.7 mmol / g or less, relative to the total amount of (M-2').

[0085] The statement that the epoxy group content in (M-2') is 0.0 mmol / g relative to the total amount of (M-2') means that (M-2') does not contain epoxy groups. (M-2') may not contain epoxy groups.

[0086] <(3) Cross-linked polymer particles (B-3)> The crosslinked polymer particles (B-3) have a core-shell structure comprising a core layer and a shell layer, wherein the shell layer contains a (meth)acrylate polymer (M-3') having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the content of the shell layer relative to the total amount of the crosslinked polymer particles (B-3) is 30% to 90% by weight. The shell layer may contain other components besides (M-3') as long as it does not impair the function of the present invention.

[0087] In the cross-linked polymer particles (B-3), the (meth)acrylate-based polymer (M-3') corresponds to the damping polymer described above.

[0088] The shell layer of the crosslinked polymer particle (B-3) preferably contains (M-3'), and more preferably consists solely of (M-3'). In other words, the shell layer of the crosslinked polymer particle (B-3) is more preferably formed by (M-3').

[0089] The content of component (M-3') in component (B-3) is preferably 30% to 90% by weight, 35% to 85% by weight, more preferably 40% to 82% by weight, more preferably more than 40% to 82% by weight, even more preferably 45% to 80% by weight, and particularly preferably 50% to 78% by weight, from the viewpoint of reducing the viscosity of the curable resin composition and improving the vibration damping properties of the cured product obtained by curing the curable resin composition.

[0090] The content of the shell layer in component (B-3) is, from the viewpoint of lowering the viscosity of the curable resin composition and improving the vibration damping properties of the cured product obtained by curing the curable resin composition, 30% by weight or more and 90% by weight or less of the total amount (100% by weight) of (B-3), preferably 35% by weight or more and 85% by weight or less, more preferably 40% by weight or more and 82% by weight or less, more preferably more than 40% by weight and 82% by weight or less, even more preferably 45% by weight or more and 80% by weight or less, and particularly preferably 50% by weight or more and 78% by weight or less.

[0091] The (meth)acrylate polymer (M-3') preferably includes a polymer obtained by graft polymerization of a monomer mixture (m-3') having a crosslinkable monomer content of 0.0% to 2.0% by weight into a core layer, and more preferably consists solely of this polymer. When (M-3') includes a polymer obtained by graft polymerization of (m-3') into a core layer, or consists solely of this polymer, the cured product obtained by curing the resulting curable resin composition has the advantage of having superior vibration damping properties.

[0092] The (meth)acrylate polymer (M-3') preferably includes a polymer obtained by graft polymerization of a monomer mixture (m-3'-a) containing 0.0% by weight of crosslinkable monomers, i.e., a monomer mixture that does not contain crosslinkable monomers, into a core layer, and more preferably consists solely of this polymer. When (M-3') includes a polymer obtained by graft polymerization of (m-3'-a) into a core layer, or consists solely of this polymer, the cured product obtained by curing the resulting curable resin composition has the advantage of having even better vibration damping properties.

[0093] Specific examples of crosslinkable monomers in (m-3') include the crosslinkable monomers described later under ((meth)acrylate polymers).

[0094] From the viewpoint of improving the vibration damping properties of the cured product obtained by curing the curable resin composition, the epoxy group content in the (meth)acrylate polymer (M-3') is preferably 0.0 mmol / g or more and 2.0 mmol / g or less, more preferably 0.0 mmol / g or more and 1.5 mmol / g or less, and even more preferably 0.0 mmol / g or more and 1.0 mmol / g or less, relative to the total amount of (M-3'). When the epoxy group content in (M-3') is 0.0 mmol / g relative to the total amount of (M-3'), it means that (M-3') does not contain epoxy groups. From the viewpoint of improving the vibration damping properties of the cured product obtained by curing the curable resin composition, it is particularly preferable that the (meth)acrylate polymer (M-3') does not contain epoxy groups (in other words, the epoxy group content in (M-3') is 0.0 mmol / g relative to the total amount of (M-3').

[0095] The crosslinked polymer particles (B-3) preferably have one or more core layers (e.g., crosslinked core layers) selected from the group consisting of diene polymers, (meth)acrylate polymers (M-3), and organosiloxane polymers. From the viewpoint of having a high effect in improving the impact resistance of the resulting cured product, and from the viewpoint of having low affinity with epoxy resin (A), which makes it less likely for viscosity to increase over time due to swelling of the core layer by component (A), the core layer of (B-3) more preferably contains a diene polymer, and more preferably consists only of a diene polymer (in other words, is a diene polymer). Furthermore, from the viewpoint of lowering the viscosity of the curable resin composition, the core layer of (B-3) preferably contains a (meth)acrylate polymer (M-3), and more preferably consists only of (M-3) (in other words, is (M-3)).

[0096] Diene polymers, (meth)acrylate polymers (M-3), and organosiloxane polymers exhibit good productivity in emulsion polymerization.

[0097] From the viewpoint of reducing the viscosity of the curable resin composition, the core layer of (B-3) more preferably contains a (meth)acrylate polymer (M-3-a) obtained by polymerizing a monomer mixture (m-3-a) containing 0.1% to 10% by weight of a crosslinkable monomer, and more preferably consists only of (M-3-a) (in other words, is (M-3-a)).

[0098] Furthermore, from the viewpoint of reducing the viscosity of the curable resin composition and improving the vibration damping properties of the resulting cured product, it is even more preferable that the core layer of (B-3) contains a (meth)acrylate polymer (M-3-b) (i.e., a damping polymer) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, obtained by polymerizing a monomer mixture (m-3-b) containing 0.1% to 10% by weight of a crosslinkable monomer, and it is particularly preferable that it consists only of (M-3-b) (in other words, it is (M-3-b)).

[0099] Furthermore, from the viewpoint of reducing the viscosity of the curable resin composition and improving the vibration damping properties of the resulting cured product, it is even more preferable that the (meth)acrylate polymer (M-3-a) contains a (meth)acrylate polymer (M-3-b) (i.e., a damping polymer) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and it is particularly preferable that it consists only of (M-3-b) (in other words, it is (M-3-b)).

[0100] Specific examples of crosslinkable monomers in (m-3-a) include the crosslinkable monomers described later under ((meth)acrylate polymers).

[0101] <Cross-linked polymer particles (B-4)> A curable resin composition according to one embodiment of the present invention has a core-shell structure comprising a diene polymer core layer and a shell layer, and may further contain crosslinked polymer particles (B-4) different from the crosslinked polymer particles (B-3). That is, the crosslinked polymer particles (B) may consist of one or more selected from the group consisting of crosslinked polymer particles (B-1), (B-2), and (B-3), and may further contain (B-4). Due to the toughness-improving effect of component (B-4), the resulting cured product has excellent impact resistance.

[0102] The glass transition temperature of the core layer of the crosslinked polymer particles (B-4) is preferably 0°C or lower, more preferably -20°C or lower, even more preferably -40°C or lower, and particularly preferably -60°C or lower, in order to increase the toughness of the resulting cured product.

[0103] The proportion of the core layer in the crosslinked polymer particles (B-4) is preferably 40% to 97% by weight, more preferably 60% to 95% by weight, even more preferably 70% to 93% by weight, and particularly preferably 80% to 90% by weight, based on 100% by weight of component (B-4). If the proportion of the core layer in 100% by weight of component (B-4) is 40% by weight or more, the impact resistance of the resulting cured product may be better. If the proportion of the core layer in 100% by weight of component (B-4) is 97% by weight or less, the core-shell polymer particles are less likely to aggregate, the curable resin composition may have lower viscosity, and the workability may be better.

[0104] The shell layer of the crosslinked polymer particles (B-4) is preferably a polymer of shell layer-forming monomers (totaling 100% by weight) that combine, for example, 0-50% by weight (preferably 1-50% by weight, more preferably 2-48% by weight) of aromatic vinyl monomer (particularly preferably styrene), 0-50% by weight (preferably 0-30% by weight, more preferably 10-25% by weight) of vinyl cyanide monomer (particularly preferably acrylonitrile), 0-100% by weight (preferably 5-100% by weight, more preferably 15-95% by weight) of (meth)acrylate monomer (particularly preferably methyl methacrylate), and 1-50% by weight (preferably 2-35% by weight, more preferably 3-20% by weight) of monomer having an epoxy group. This makes it possible to achieve a good balance between the desired toughness improvement effect and mechanical properties.

[0105] The cross-linked polymer particles (B-4) may or may not have epoxy groups in their shell layer, but it is preferable that they have epoxy groups in their shell layer. When the shell layer of (B-4) has epoxy groups, the content of epoxy groups in the shell layer relative to the total amount of the shell layer of the cross-linked polymer particles (B-4) is preferably 0.1 mmol / g or more and 2.0 mmol / g or less, and more preferably 0.3 mmol / g or more and 1.5 mmol / g or less, from the viewpoint of the impact resistance of the resulting cured product. This suppresses aggregation of the cross-linked polymer particles (B-4), allowing the cross-linked polymer particles (B-4) to be dispersed in the cured product as primary particles, and as a result, it is presumed that the impact resistance of the cured product may be improved.

[0106] When using (B-4), the amount of (B-4) is preferably 1 to 80 parts by weight, more preferably 5 to 70 parts by weight, even more preferably 10 to 60 parts by weight, and particularly preferably 20 to 55 parts by weight, per 100 parts by weight of the total amount of (B) component. When (B-4) is (a) 1 part by weight or more per 100 parts by weight of the total amount of (B) component, the improvement effects on toughness, impact resistance, adhesion, etc. are good, and when it is 80 parts by weight or less, the vibration damping properties of the resulting cured product are high.

[0107] ((meth)acrylate polymer) The (meth)acrylate polymer is a polymer that can be used as the core layer of the crosslinked polymer particles (B-1, B-2, B-3) and as the shell layer of (B-1, B-2, B-3, B-4), and is a polymer that can contribute to improving the vibration damping properties of the cured product.

[0108] In this specification, "(meth)acrylate polymer" refers to a polymer obtained by polymerizing a monomer mixture containing 30% by weight or more of at least one monomer selected from the group consisting of (meth)acrylate monomers, in a 100% by weight mixture.

[0109] The (meth)acrylate polymer is preferably a polymer obtained by polymerizing a monomer mixture containing 30% to 100% by weight (more preferably 40% to 100% by weight, even more preferably 50% to 100% by weight) of at least one monomer selected from the group consisting of (meth)acrylate monomers, and 0% to 70% by weight (more preferably 0% to 60% by weight, even more preferably 0% to 50% by weight) of another vinyl monomer copolymerizable with the (meth)acrylate monomer. The (meth)acrylate polymer may also consist of only at least one monomer selected from the group consisting of (meth)acrylate monomers.

[0110] Furthermore, the (meth)acrylate polymer is a polymer obtained by polymerizing a monomer mixture containing 0% to 100% by weight of non-crosslinkable monomers and 0% to 100% by weight of crosslinkable monomers. In other words, the (meth)acrylate polymer may have only constituent units derived from non-crosslinkable monomers, or only constituent units derived from crosslinkable monomers, or it may have both constituent units derived from non-crosslinkable monomers and constituent units derived from crosslinkable monomers.

[0111] Examples of the (meth)acrylate monomers include (i) alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, and behenyl (meth)acrylate; (ii) aromatic ring-containing (meth)acrylates such as phenoxyethyl (meth)acrylate and benzyl (meth)acrylate; (iii) 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate. Examples include hydroxyalkyl (meth)acrylates such as (iv) glycidyl (meth)acrylates such as glycidyl (meth)acrylate and glycidylalkyl (meth)acrylate; (v) alkoxyalkyl (meth)acrylates; (vi) allylalkyl (meth)acrylates such as allyl (meth)acrylate and allylalkyl (meth)acrylate; and (vii) polyfunctional (meth)acrylates such as monoethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate. These (meth)acrylate monomers may be used individually or in combination of two or more. Preferred (meth)acrylate monomers are ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0112] Other vinyl monomers copolymerizable with (meth)acrylate monomers include, for example, (i) vinylarenes 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) vinyl halides such as vinyl chloride, vinyl bromide, and chloroprene; (v) vinyl acetate; (vi) alkenes such as ethylene, propylene, butylene, and isobutylene; and (vii) polyfunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene. These vinyl monomers may be used individually or in combination of two or more. Among these, styrene is particularly preferred because it can easily increase the refractive index.

[0113] Examples of the crosslinkable monomers include conjugated diene monomers such as butadiene, and include allylalkyl(meth)acrylates such as allyl(meth)acrylate and allylalkyl(meth)acrylate; allyloxyalkyl(meth)acrylates; polyfunctional(meth)acrylates having two or more (meth)acrylic 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, and divinylbenzene, but allyl methacrylate and triallyl isocyanurate are preferred. These crosslinkable monomers may be used individually or in combination of two or more.

[0114] (Particle size of cross-linked polymer particles (B)) The particle size of the crosslinked polymer particles (B) is not particularly limited, but considering industrial productivity, the volume-average particle size (Mv) is preferably 10 nm to 2000 nm, more preferably 30 nm to 600 nm, even more preferably 50 nm to 500 nm, and particularly preferably 100 nm to 400 nm. The volume-average particle size (Mv) of the polymer particles can be measured for the latex of the polymer particles using a Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.).

[0115] In the curable resin composition, it is preferable that the crosslinked polymer particles (B) have a width at half maximum of 0.5 times or more and 1 time or less of the volume-average particle diameter in their number distribution, because this results in a curable resin composition with low viscosity and easy handling.

[0116] From the viewpoint of easily realizing the specific particle size distribution described above, it is preferable that there are two or more maximum values ​​in the particle size number distribution of the crosslinked polymer particles (B), and from the viewpoint of manufacturing effort and cost, it is more preferable that there are two to three maximum values, and even more preferable that there are two maximum values. In particular, it is preferable that the crosslinked polymer particles (B) contain 10% to 90% by weight of crosslinked 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 crosslinked polymer particles with a volume average particle size of 150 nm or more and 2000 nm or less.

[0117] It is preferable that the crosslinked polymer particles (B) are dispersed in the curable resin composition as primary particles. In this specification, "crosslinked polymer particles dispersed as primary particles" (hereinafter also referred to as primary dispersion) means that the crosslinked polymer particles are dispersed substantially independently (without contact) with each other, and this 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 the particle size using a particle size analyzer that measures laser light scattering.

[0118] The value of volume-average particle diameter (Mv) / number-average particle diameter (Mn) obtained by the 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. If the volume-average particle diameter (Mv) / number-average particle diameter (Mn) is 3.0 or less, it is considered that the cross-linked polymer particles (B) are well dispersed, and the physical properties such as impact resistance and adhesion (adhesion strength) of the resulting cured product are good.

[0119] The volume-average particle diameter (Mv) / number-average particle diameter (Mn) can be calculated by measuring Mv using a Microtrac UPA (manufactured by Nikkiso Co., Ltd.) and dividing Mv by Mn.

[0120] Furthermore, "stable dispersion" of crosslinked polymer particles means that the crosslinked polymer particles remain dispersed in a continuous layer under normal conditions for a long period of time without agglomerating, separating, or settling. It is also preferable that the distribution of crosslinked polymer particles in the continuous layer does not change substantially, and that the "stable dispersion" can be maintained even when these compositions are heated to a safe extent to reduce viscosity and then stirred.

[0121] The cross-linked polymer particles (B) may be used individually or in combination of two or more types.

[0122] The structure of the crosslinked polymer particles (B-1) may be a single layer or a structure of two or more layers, and is not particularly limited. It is preferable that the crosslinked polymer particles (B-1) have a structure of two or more layers, and more preferably have a core-shell structure including a core layer and a shell layer.

[0123] Furthermore, if the cross-linked polymer particles (B-1 to B-3) have a core-shell structure, it is also possible to have a structure of three or more layers, consisting of an intermediate layer covering the core layer and a shell layer further covering this intermediate layer.

[0124] The following describes each layer of the cross-linked polymer particles (B) in detail.

[0125] Unless otherwise specified, "core layer" refers to all core layers of the cross-linked polymer particles having a core-shell structure in (B-1), the core layer of (B-2), the core layer of (B-3), and the core layer of (B-4). Furthermore, "intermediate layer" refers to all intermediate layers of the cross-linked polymer particles having a core-shell structure in (B-1), the intermediate layer of (B-2), the intermediate layer of (B-3), and the intermediate layer of (B-4). Furthermore, "shell layer" refers to all shell layers of the cross-linked polymer particles having a shell-shell structure in (B-1), the shell layer of (B-2), the shell layer of (B-3), and the shell layer of (B-4).

[0126] ≪Core Layer≫ The core layers of the crosslinked polymer particles (B-1), (B-3), and (B-4) preferably have a gel content of 60% by weight or more, more preferably 80% by weight or more, even more preferably 90% by weight or more, and particularly preferably 95% by weight or more. In this specification, gel content refers to the ratio of insoluble matter to the total amount of insoluble matter when 0.5 g of crumb obtained by solidification and drying is immersed in 100 g of toluene, left to stand at 23°C for 24 hours, and then the insoluble matter and soluble matter are separated.

[0127] From the viewpoint of productivity in emulsion polymerization, the core layer preferably contains one or more polymers selected from the group consisting of diene polymers, (meth)acrylate polymers, and organosiloxane polymers, as shown below.

[0128] (Diene polymer) The diene polymer is a polymer that can be used as a core layer for the crosslinked polymer particles (B-3) and (B-4), and the impact resistance of the resulting cured product can be improved.

[0129] Examples of conjugated diene monomers constituting the aforementioned diene polymer include 1,3-butadiene, isoprene, 2-chloro-1,3-butadiene, and 2-methyl-1,3-butadiene. These conjugated diene monomers may be used individually or in combination of two or more.

[0130] The content of the conjugated diene monomer is preferably in the range of 50 to 100% by weight of the core layer, more preferably in the range of 70 to 100% by weight, and even more preferably in the range of 90 to 100% by weight. When the content of the conjugated diene monomer is 50% by weight or more, the impact resistance of the resulting cured product may be better.

[0131] Examples of vinyl monomers copolymerizable with conjugated diene monomers include vinylarenes 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; vinyl halides such as vinyl chloride, vinyl bromide, and chloroprene; vinyl acetate; alkenes such as ethylene, propylene, butylene, and isobutylene; and polyfunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene. These vinyl monomers may be used individually or in combination of two or more. Styrene is particularly preferred.

[0132] The content of the vinyl monomer copolymerizable with the conjugated diene monomer 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. If the content of the vinyl monomer copolymerizable with the conjugated diene monomer is 50% by weight or less, the impact resistance of the resulting cured product may be better.

[0133] Because of its high impact resistance improvement effect and its low affinity with epoxy resin (A), which makes it less likely for viscosity to increase over time due to swelling of the core layer, the diene rubber is preferably a butadiene rubber using 1,3-butadiene, and / or a butadiene-styrene rubber which is a copolymer of 1,3-butadiene and styrene, with butadiene rubber being more preferred. Furthermore, butadiene-styrene rubber is preferred because its transparency of the cured product can be increased by adjusting the refractive index.

[0134] ((meth)acrylate copolymer) The (meth)acrylate copolymer is a polymer that can be used as the core layer of the crosslinked polymer particles (B-1), (B-2), and (B-3), and the same polymer as the (meth)acrylate copolymer specifically exemplified above is an example.

[0135] The (meth)acrylate polymers (M-1 to M-3) that can be used as the core layer of the crosslinked polymer particles (B-1 to M-3) are preferably (meth)acrylate polymers (M-1 to M-3) obtained by polymerizing a monomer mixture (m-1 to M-3) having a styrene monomer content of 10% to 70% by weight, from the viewpoint of improving the vibration damping properties of the cured product obtained by curing the curable resin composition. The styrene monomer content in 100% by weight of the monomer mixture (m-1 to M-3) is more preferably 20% to 60% by weight, even more preferably 25% to 55% by weight, and particularly preferably 30% to 50% by weight.

[0136] Crosslinked polymer particles (B-1~3) refer to any one or more crosslinked polymer particles from among crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3). (Meth)acrylate polymers (M-1~3) refer to any one or more (meth)acrylate polymers from among (meth)acrylate polymers (M-1), (meth)acrylate polymers (M-2), and (meth)acrylate polymers (M-3). Monomer mixtures (m-1~3) refer to any one or more monomer mixtures from among monomer mixtures (m-1), monomer mixtures (m-2), and monomer mixtures (m-3).

[0137] Examples of the aforementioned styrene monomers include styrene, α-methylstyrene, and monochlorostyrene.

[0138] The (meth)acrylate polymers (M-1 to M-3) are preferably (meth)acrylate polymers (M-1 to M-3) obtained by polymerizing monomer mixtures (m-1 to M-3) having a content of 50% to 90% by weight of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms (C3 to C20), from the viewpoint of improving the vibration damping properties of the cured product obtained by curing the curable resin composition, and from the viewpoint of improving the workability of the curable resin composition. In this specification, "unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms" may be referred to as "unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms" or "C3 to C20 unsubstituted alkyl (meth)acrylate". The content of unsubstituted alkyl (meth)acrylates having 3 to 20 carbon atoms in 100% by weight of monomer mixture (m-1 to m-3) is more preferably 51% to 80% by weight, even more preferably 52% to 70% by weight, and particularly preferably 53% to 65% by weight.

[0139] Examples of unsubstituted alkyl (meth)acrylates having 3 to 20 carbon atoms include n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, and stearyl (meth)acrylate. Among these, isobutyl (meth)acrylate and 2-ethylhexyl (meth)acrylate, which have branched alkyl groups, are more preferable because they improve the vibration damping effect of the cured product, or the curable resin composition has a low viscosity and improves workability.

[0140] (Organosiloxane polymers) Examples of the organosiloxane polymers include (i) polysiloxane polymers composed of alkyl or aryl 2-substituted silyloxy units such as dimethylsilyloxy, diethylsilyloxy, methylphenylsilyloxy, diphenylsilyloxy, and dimethylsilyloxy-diphenylsilyloxy; and (ii) polysiloxane polymers composed of alkyl or aryl 1-substituted silyloxy units such as organohydrogensilyloxy, in which part of the alkyl in the side chain is substituted with a hydrogen atom. These polysiloxane polymers may be used individually or in combination of two or more. Among these, dimethylsilyloxy, methylphenylsilyloxy, and dimethylsilyloxy-diphenylsilyloxy are preferred because they can impart heat resistance to the cured product, and dimethylsilyloxy is most preferred because it is readily available. In an embodiment in which the core layer is formed from organosiloxane rubber, it is preferable that the polysiloxane polymer portion is contained in an amount of 80% by weight or more (more preferably 90% by weight or more) of the total organosiloxane rubber, relative to 100% by weight, in order not to impair the heat resistance of the cured product.

[0141] Furthermore, the volume-average particle size of the core layer is preferably 0.03 μm to 2 μm, and more preferably 0.05 μm to 1 μm. Within this range, stable manufacturing is possible, and the cured product may have good heat resistance and impact resistance. The volume-average particle size can be measured using Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.).

[0142] The core layer is often a single-layer structure, but it may also be a multilayer structure. Furthermore, if the core layer is a multilayer structure, the polymer composition of each layer may differ within the scope of the disclosure. For example, when crosslinked polymer particles are used and the core layer is multilayer in (B-1), it is preferable that all layers in the core layer are damping polymers.

[0143] ≪Middle Class≫ An intermediate layer may be formed between the core layer and the shell layer, if necessary. In particular, the following surface crosslinking layer may be formed as the intermediate layer. It is preferable to include an intermediate layer, and in particular, it is preferable to include the following surface crosslinking layer, as this reduces the viscosity of the resulting curable resin composition and improves its workability. When an intermediate layer is formed, it is sufficient to cover at least a part of the core layer, or it may cover the entire core layer.

[0144] If an intermediate layer is present, the ratio of the intermediate layer to 100 parts by weight of the core layer is preferably 0.1 to 30 parts by weight, more preferably 0.2 to 20 parts by weight, even more preferably 0.5 to 10 parts by weight, and particularly preferably 1 to 5 parts by weight.

[0145] The aforementioned surface crosslinked layer consists of an intermediate layer polymer obtained by polymerizing a surface crosslinked layer component comprising 30 to 100% by weight of a crosslinkable monomer having two or more radical polymerizable double bonds in one molecule, and 0 to 70% by weight of other vinyl monomers. This polymer has the effect of reducing the viscosity of the curable resin composition and improving the dispersibility of crosslinked polymer particles (B) in component (A). It also has the effect of increasing the crosslinking density of the core layer and improving the grafting efficiency of the shell layer.

[0146] Specific examples of crosslinkable monomers having two or more radical polymerizable double bonds include the same monomers as those described above, but allyl methacrylate and triallyl isocyanurate are preferred.

[0147] ≪Shell Layer≫ The outermost shell layer of the crosslinked polymer particles is formed by polymerizing a shell layer-forming monomer. This shell polymer plays a role in improving the compatibility between the crosslinked polymer particles (B) and component (A), enabling the crosslinked polymer particles (B) to be dispersed as primary particles in the curable resin composition or its cured product.

[0148] Such shell polymers are preferably grafted onto the core layer and / or intermediate layer. Hereafter, when referring to "grafted onto the core layer," this also includes the case where an intermediate layer is formed on the core layer, in which case the shell polymer is grafted onto the intermediate layer. More precisely, it is preferable that the monomer component used to form the shell layer is graft polymerized onto the core polymer forming the core layer (if an intermediate layer is formed, the core polymer also includes the intermediate layer polymer that forms the intermediate layer; the same applies hereinafter) so that the shell polymer and the core polymer are substantially chemically bonded (if an intermediate layer is formed, it is also preferable that the shell polymer and the intermediate layer polymer are chemically bonded). That is, preferably, the shell polymer is formed by graft polymerizing the shell layer-forming monomer in the presence of the core polymer, thereby graft polymerizing onto the core polymer and covering part or all of the core polymer. This polymerization operation can be carried out by adding the shell polymer layer-forming monomer to the latex of the core polymer prepared in an aqueous polymer latex state and polymerizing it.

[0149] As the monomer for forming the shell layer, from the viewpoint of compatibility and dispersibility of the crosslinked polymer particles (B) in the curable resin composition, for example, aromatic vinyl monomers, vinyl cyanide monomers, or (meth)acrylate monomers can be used, but (meth)acrylate monomers are more preferred. In particular, the monomer for forming the shell layer preferably contains methyl methacrylate and / or butyl (meth)acrylate. These shell layer forming monomers may be used alone or in appropriate combinations. The shell layer only needs to cover at least a part of the core layer and / or intermediate layer, or it may cover all of them.

[0150] The (meth)acrylate polymer (M-1'~3') that can be used as a shell layer for crosslinked polymer particles (B-1~3) is preferably a (meth)acrylate polymer (M-1'~3') obtained by polymerizing a monomer mixture (m-1'~3') having an alkyl (meth)acrylate with one or two carbon atoms in the alkyl group (C1~C2) in a content of 70% to 100% by weight, from the viewpoint of improving the T-peel adhesion of the curable resin composition. In this specification, "alkyl (meth)acrylate with one or two carbon atoms in the alkyl group" may be referred to as "alkyl (meth)acrylate with one or two carbon atoms" or "C1~C2 alkyl (meth)acrylate". The content of C1 or C2 alkyl (meth)acrylate in 100% by weight of monomer mixture (m-1'~3') is more preferably 71% by weight or more and 99% by weight or less, even more preferably 72% by weight or more and 98% by weight or less, and particularly preferably 75% by weight or more and 95% by weight or less.

[0151] (Meth)acrylate polymers (M-1'~3') refer to any one or more (meth)acrylate polymers from among (meth)acrylate polymers (M-1'), (meth)acrylate polymers (M-2'), and (meth)acrylate polymers (M-3'). Monomer mixtures (m-1'~3') refer to any one or more monomer mixtures from among monomer mixtures (m-1'), monomer mixtures (m-2'), and monomer mixtures (m-3').

[0152] Examples of alkyl (meth)acrylates having 1 or 2 carbon atoms include methyl (meth)acrylate and ethyl (meth)acrylate. Among these, methyl acrylate and ethyl acrylate are more preferred from the viewpoint of improving the workability of the curable resin composition.

[0153] In order to maintain a good dispersion state without aggregation of crosslinked polymer particles (B) in the cured product or curable resin composition, the monomer for forming the shell layer may contain one or more reactive group-containing monomers selected from the group consisting of epoxy groups, oxetane groups, hydroxyl groups, amino groups, imide groups, carboxylic acid groups, carboxylic acid anhydride groups, cyclic esters, cyclic amides, benzoxazine groups, and cyanate ester groups, from the viewpoint of chemically bonding with component (A). In particular, monomers having epoxy groups are preferred.

[0154] From the viewpoint of impact-resistant peel adhesion and storage stability, monomers having epoxy groups are preferably present in an amount of 0% to 90% by weight, more preferably 1% to 50% by weight, even more preferably 2% to 35% by weight, and particularly preferably 3% to 20% by weight, in 100% by weight of the monomer for forming the shell layer.

[0155] Monomers having epoxy groups are preferably used to form the shell layer, and more preferably used only for the shell layer.

[0156] Furthermore, using a crosslinkable monomer having two or more radically polymerizable double bonds as a monomer for forming the shell layer is preferable because it prevents swelling of core-shell polymer particles in the curable resin composition and tends to result in a lower viscosity and better handling of the curable resin composition. On the other hand, from the viewpoint of improving the toughness and damping properties and impact resistance of the resulting cured product, it is preferable not to use a crosslinkable monomer having two or more radically polymerizable double bonds as a monomer for forming the shell layer.

[0157] Specific examples of the aromatic vinyl monomers include vinylbenzenes such as styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene.

[0158] Specific examples of the vinyl cyanide monomer include acrylonitrile or methacrylonitrile.

[0159] Specific examples of (meth)acrylate monomers other than the C1 or C2 alkyl (meth)acrylates mentioned above include alkyl (meth)acrylates with 3 or more carbon atoms, such as butyl (meth)acrylate; and hydroxyalkyl (meth)acrylate esters.

[0160] Specific examples of the aforementioned hydroxyalkyl (meth)acrylate include, for example, hydroxylinear alkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate (especially hydroxylinear C1-6 alkyl (meth)acrylate); caprolactone-modified hydroxy (meth)acrylate; hydroxybranched alkyl (meth)acrylates such as α-(hydroxymethyl)acrylate and α-(hydroxymethyl)acrylate; and hydroxyl group-containing (meth)acrylates such as mono(meth)acrylates of polyester diols (especially saturated polyester diols) obtained from divalent carboxylic acids (such as phthalic acid) and divalent alcohols (such as propylene glycol).

[0161] Specific examples of monomers having the epoxy group include glycidyl group-containing vinyl monomers such as glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, and allyl glycidyl ether.

[0162] Specific examples of crosslinkable monomers having two or more radical polymerizable double bonds include the same monomers as those described above, but allyl methacrylate and triallyl isocyanurate are preferred.

[0163] These monomer components may be used individually or in combination of two or more. The shell layer may be formed by including other monomer components in addition to the above monomer components. When using crosslinked polymer particles (B-3), it is preferable that the monomer for shell layer formation is a polymer that does not contain structural units containing alkoxy groups, aryloxy groups, oxetane groups, or hydroxyl groups, but contains at least one of structural units derived from alkyl methacrylate and structural units derived from alkyl acrylate. In this case, a (meth)acrylate-based polymer with a glass transition temperature of -20°C to 30°C, as determined by the Fox formula, can be easily formed using a general-purpose monomer.

[0164] 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 may have a lower viscosity.

[0165] The method for calculating the graft rate is as follows. First, an aqueous latex containing core-shell polymer particles is coagulated and dehydrated, and finally dried to obtain a core-shell polymer particle powder. Next, 2 g of the core-shell polymer particle powder is immersed in 100 g of methyl ethyl ketone (MEK) at 23°C for 24 hours, after which the MEK-soluble portion is separated from the MEK-insoluble portion, and then the methanol-insoluble portion is separated from the MEK-soluble portion. The graft rate is then calculated by determining the ratio of the MEK-insoluble portion to the total amount of MEK-insoluble portion and methanol-insoluble portion.

[0166] ≪Method for producing cross-linked polymer particles≫ (Method of manufacturing the core layer) The core layer constituting the crosslinked polymer particles (B) can be produced by, for example, emulsion polymerization, suspension polymerization, or microsuspension polymerization, and the methods described in, for example, International Publication No. 2005 / 028546 or International Publication No. 2006 / 070664 can be used.

[0167] (Method for forming shell layers and intermediate layers) The intermediate layer can be formed by polymerizing the intermediate layer-forming monomer by known radical polymerization in the presence of the core layer. When the rubber elastic material constituting the core layer is obtained as an emulsion, it is preferable to polymerize the intermediate layer-forming monomer by emulsion polymerization. A polymer formed by coating the core layer with the intermediate layer (polymerizing the intermediate layer-forming monomer onto the core layer) is sometimes referred to as a "polymer particle precursor."

[0168] The shell layer can be formed by polymerizing a shell layer-forming monomer by known radical polymerization in the presence of a core layer or polymer particle precursor. When the core layer or polymer particle precursor is obtained as an emulsion, polymerization of the shell layer-forming monomer is preferably carried out by emulsion polymerization, and can be produced, for example, according to the method described in International Publication No. 2005 / 028546.

[0169] Examples of emulsifiers (dispersants) that can be used in emulsion polymerization include various acids such as alkyl or aryl sulfonic acids, alkyl or aryl ether sulfonic acids, alkyl or aryl sulfuric acids, alkyl or aryl sulfuric acids, alkyl or aryl sulfuric acids, alkyl or aryl ether sulfuric acids, alkyl or aryl substituted phosphoric acids, alkyl or aryl substituted phosphoric acids, N-alkyl or aryl sarcosinic acids, alkyl or aryl carboxylic acids, alkyl or aryl ether carboxylic acids, alkali metal salts or ammonium salts of these acids, anionic 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) may be used individually or in combination of two or more.

[0170] It is preferable to use as little emulsifier (dispersant) as possible, as long as it does not impair the dispersion stability of the polymer particles in the aqueous latex. Furthermore, the higher the water solubility of the emulsifier (dispersant), the better. High water solubility makes it easier to wash away the emulsifier (dispersant) with water, and thus easily prevents adverse effects on the final cured product.

[0171] When employing emulsion polymerization, known initiators, namely pyrolysis-type initiators such as 2,2'-azobisisobutyronitrile, hydrogen peroxide, potassium persulfate, and ammonium persulfate, can be used.

[0172] Furthermore, when employing emulsion polymerization, a redox-type initiator can be used which comprises (i) (i-1) organic peroxides such as t-butyl peroxyisopropyl carbonate, paramentane hydroperoxide, cumene hydroperoxide, dicumyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, and t-hexyl peroxide, and (i-2) inorganic peroxides such as hydrogen peroxide, potassium persulfate, and ammonium persulfate, in combination with (ii) a reducing agent such as sodium formaldehyde sulfoxylate and glucose, and / or a transition metal salt such as iron(II) sulfate. In the use of the aforementioned redox-type initiator, a chelating agent such as disodium ethylenediaminetetraacetate and a phosphorus-containing compound such as sodium pyrophosphate may be used in combination as needed.

[0173] When a redox-type initiator system is used, polymerization can be carried out even at low temperatures in which the peroxide does not substantially decompose thermally, allowing the polymerization temperature to be set over a wide range. For this reason, it is preferable to use a redox-type initiator system. Among redox-type initiators, redox-type initiators using organic peroxides such as cumene hydroperoxide, dicumyl peroxide, and t-butyl hydroperoxide as peroxides are preferred. The amount of thermal decomposition-type initiator used and the amount of redox-type initiator used, as well as the amount of reducing agent, transition metal salt, and chelating agent used when a redox-type initiator is used, can be used within known limits. Furthermore, when polymerizing monomers having two or more radically polymerizable double bonds, known chain transfer agents can be used within known limits. Surfactants can also be used in addition, but this is also within known limits.

[0174] The polymerization conditions, such as polymerization temperature, pressure, and deoxygenation, used during the polymerization of each layer can be those within the known range. Furthermore, the polymerization of the intermediate layer-forming monomer may be carried out in one stage or in two or more stages. For example, methods such as adding the intermediate layer-forming monomer to the emulsion of the rubber elastic material constituting the elastic core layer all at once, or adding it continuously, or adding the emulsion of the rubber elastic material constituting the elastic core layer to a reactor that has already been charged with the intermediate layer-forming monomer before polymerization can be employed.

[0175] <Blocked Urethane (C)> In one embodiment of the present invention, blocked urethane (C) may be used as needed. Hereinafter, "blocked urethane (C)" may be referred to as "component (C)". When this curable resin composition contains component (C), the resulting cured product has excellent toughness and elongation properties due to the toughness-improving effect of component (C).

[0176] In this specification, blocked urethane refers to an elastomer-type compound containing urethane groups and / or urea groups, and having isocyanate groups at its terminals, wherein all or part of the terminal isocyanate groups are capped with various blocking agents having active hydrogen groups. Compounds in which all of the terminal isocyanate groups are capped with a blocking agent are particularly preferred. Such compounds can be obtained, for example, by reacting an excess polyisocyanate compound with an organic polymer having an active hydrogen-containing group at its terminals to form a polymer (urethane prepolymer) having urethane groups and / or urea groups in the main chain and isocyanate groups at its terminals, and then simultaneously capping all or part of the isocyanate groups with a blocking agent having active hydrogen groups.

[0177] Specific examples of blocked urethanes include the compounds described in International Publication No. 2016 / 163491.

[0178] The number-average molecular weight of the blocked urethane is preferably 2,000 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000, as measured by GPC in terms of polystyrene-equivalent molecular weight. This configuration has the advantage that the resulting curable resin composition has excellent adhesion (adhesion strength) and workability. The molecular weight distribution of the blocked urethane (ratio of weight-average molecular weight to number-average molecular weight (weight-average molecular weight / number-average molecular weight)) is preferably 1.0 to 4.0, more preferably 1.2 to 3.0, and particularly preferably 1.5 to 2.5. This configuration has the advantage that the resulting curable resin composition has excellent workability.

[0179] Blocked urethane can be used individually or in combination of two or more types.

[0180] When the curable resin composition contains component (C), the content of blocked urethane in the curable resin composition is preferably 1 to 50 parts by weight, more preferably 2 to 40 parts by weight, and more preferably 5 to 30 parts by weight, per 100 parts by weight of epoxy resin (A). When the content of blocked urethane in the curable resin composition is (a) 1 part by weight or more per 100 parts by weight of epoxy resin (A), the improvement effect on toughness, impact resistance, adhesion (adhesion strength), etc. is good, and when it is (b) 50 parts by weight or less, the elastic modulus of the resulting cured product is high.

[0181] <Epoxy resin hardener (D)> In one embodiment of the present invention, an epoxy resin curing agent (D) may be used as needed. Hereinafter, "epoxy resin curing agent (D)" may be referred to as "component (D)".

[0182] The case in which this curable resin composition is used as a one-component composition (for example, a one-component curable resin composition) will be described. In this case, it is preferable to select the type and amount of component (D) so that the curable resin composition hardens rapidly when heated to a temperature of 80°C or higher, preferably 140°C or higher. Conversely, it is preferable to select the type and amount of component (D) and component (E), described later, so that the curable resin composition hardens very slowly at room temperature (about 22°C) and at temperatures up to at least 50°C, even if it does harden.

[0183] (D) Component can be a component that becomes active upon heating (sometimes referred to as a latent epoxy curing agent). Such latent epoxy curing agents can be nitrogen (N)-containing curing agents such as certain amine curing agents (including imine curing agents). Examples of (D) component include boron trichloride / amine complex, boron trifluoride / amine complex, dicyandiamide, melamine, diallylmelamine, guanamine (e.g., acetoguanamine and benzoguanamine), aminotriazole (e.g., 3-amino-1,2,4-triazole), hydrazides (e.g., dihydrazide adipic acid, dihydrazide stearate, dihydrazide isophthalic acid, semicarbazide), cyanoacetamide, and aromatic polyamines (e.g., metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, etc.). As component (D), it is more preferable to use dicyandiamide, isophthalic acid dihydrazide, adipic acid dihydrazide, or 4,4'-diaminodiphenylsulfone because they have excellent adhesive properties (adhesive strength), and it is particularly preferable to use dicyandiamide.

[0184] Among the components (D) mentioned above, latent epoxy curing agents are preferred because they enable the use of this curable resin composition as a one-component curable resin composition.

[0185] Next, we will describe the case in which this curable resin composition is used as a two-component or multi-component composition. In this case, amine-based curing agents (including imine-based curing agents) and / or mercaptan-based curing agents (sometimes referred to as room-temperature curing agents) other than those mentioned above can be selected as component (D) which exhibits activity at relatively low temperatures, such as room temperature.

[0186] Examples of components (D) that exhibit activity at relatively low temperatures, such as room temperature, include amine-based curing agents such as polyamidoamines, amine-terminated polyethers, amine-terminated rubbers, modified aliphatic polyamines, modified alicyclic polyamines, and polyamides, as well as various compounds described in paragraph

[0113] of the specification of WO2016-163491.

[0187] Amine-terminated polyethers containing a polyether backbone and having an average of 1 to 4 (preferably 1.5 to 3) amino groups and / or imino groups per molecule can also be used as component (D), exhibiting activity at relatively low temperatures such as room temperature. Examples of commercially available amine-terminated polyethers include Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, and Jeffamine T-5000 from Huntsman.

[0188] Furthermore, amine-terminated rubbers containing a conjugated diene polymer backbone and having an average of 1 to 4 (more preferably 1.5 to 3) amino groups and / or imino groups per molecule can also be used as component (D), which exhibits activity at relatively low temperatures such as room temperature. Here, the rubber backbone, i.e., the conjugated diene polymer backbone, is preferably a polybutadiene homopolymer or copolymer, more preferably a polybutadiene / acrylonitrile copolymer, and particularly preferably a polybutadiene / acrylonitrile copolymer with an acrylonitrile monomer content of 5 to 40% by mass (more preferably 10 to 35% by mass, even more preferably 15 to 30% by mass). A commercially available amine-terminated rubber is Hypro 1300X16 ATBN manufactured by CVC.

[0189] Among the amine-based curing agents that exhibit activity at relatively low temperatures, such as room temperature, polyamidoamines, amine-terminated polyethers, and amine-terminated rubbers are more preferred, and the combined use of polyamidoamines, amine-terminated polyethers, and amine-terminated rubbers is particularly preferred.

[0190] Furthermore, among the components of (D), acid anhydrides and phenols can also be used as latent epoxy curing agents. Although acid anhydrides and phenols require higher temperatures compared to amine-based curing agents, they have a longer pot life, and the resulting cured product has a good balance of physical properties such as electrical, chemical, and mechanical properties. Examples of acid anhydrides include the various compounds described in paragraph

[0117] of the specification of WO2016-163491.

[0191] (D) Component may be used alone or in combination of two or more types.

[0192] Component (D) may be used in an amount sufficient to cure the curable resin composition. Typically, an amount sufficient to consume at least 80% of the epoxide groups present in the curable resin composition may be used. A large excess amount of component (D) beyond what is necessary to consume the epoxide groups is usually not required.

[0193] The curable resin composition preferably contains 1 to 80 parts by mass of epoxy curing agent (D) per 100 parts by mass of epoxy resin (A), more preferably 2 to 40 parts by mass, even more preferably 3 to 30 parts by mass, and particularly preferably 5 to 20 parts by mass of epoxy curing agent (D). When the content of component (D) is (a) 1 part by mass or more per 100 parts by mass of component (A), the curability of the curable resin composition is good, and when it is (b) 80 parts by mass or less, the storage stability of the curable resin composition is good and it has the advantage of being easy to handle.

[0194] <Curing accelerator (E)> In one embodiment of the present invention, a curing accelerator (E) may be used as needed. Hereinafter, the "curing accelerator (E)" may be referred to as "component (E)". Component (E) is a compound that functions as a catalyst to promote the reaction between an epoxy group and an epoxide reactive group possessed by a component other than the epoxy resin (A) contained in the curing agent and the curable resin composition.

[0195] (E) The component is not particularly limited as long as it has the catalytic activity described above, but for example, (a) ureas such as 3-(3,4-dichlorophenyl)-1,1-dimethylurea, p-chlorophenyl-N,N-dimethylurea (trade name: Monuron), 3-phenyl-1,1-dimethylurea (trade name: Fenuron), 3,4-dichlorophenyl-N,N-dimethylurea (trade name: Diuron), N-(3-chloro-4-methylphenyl)-N',N'-dimethylurea (trade name: Chlortoluron), 1,1-dimethylphenylurea (trade name: Dyhard); (b) benzyldimethylamine, 2,4,6-tris(di Examples include methylaminomethyl)phenol, 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol incorporated into a poly(p-vinylphenol) matrix, triethylenediamine, and tertiary amines such as N,N-dimethylpiperidine; (c) imidazoles such as C1-C12 alkyleneimidazole, N-arylimidazole, 2-methylimidazole, 2-ethyl-2-methylimidazole, N-butylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, and addition products of epoxy resin and imidazole; and (d) 6-caprolactam. Component (E) may be encapsulated in microcapsules or the like, or may be a potential catalyst that becomes active only when the temperature is raised.

[0196] Furthermore, among the components of (E), tertiary amines and imidazoles can be used in combination with amine-based curing agents of component (D) (for example, component (D) that exhibits activity at relatively low temperatures such as room temperature) to improve the curing speed and the physical properties and heat resistance of the resulting cured product.

[0197] (E) Component may be used alone or in combination of two or more types.

[0198] The curable resin composition preferably contains 0.1 to 10.0 parts by mass, more preferably 0.2 to 5.0 parts by mass, even more preferably 0.5 to 3.0 parts by mass, and particularly preferably 0.8 to 2.0 parts by mass of a curing accelerator (E) per 100 parts by mass of epoxy resin (A). When the content of component (E) is (a) 0.1 parts by mass or more per 100 parts by mass of component (A), the curability of the curable resin composition is good, and when it is (b) 10.0 parts by mass or less, the storage stability of the curable resin composition is good, and it has the advantage of being easy to handle.

[0199] <Reinforcement agent> The curable resin composition of one embodiment of the present invention may optionally contain, as a reinforcing agent, for example, an unmodified epoxy rubber polymer, in order to further improve the properties of the cured product, such as toughness, impact resistance, shear adhesion, and peel adhesion. The reinforcing agent may be used alone or in combination of two or more types.

[0200] <Epoxy-unmodified rubber polymer> In this specification, an unmodified epoxy rubber polymer refers to an unmodified rubber polymer that has not reacted with (been modified by) an epoxy resin. That is, the rubber polymer may be included in the curable resin composition of one embodiment of the present invention in its unmodified state, without being reacted with an epoxy resin, as needed.

[0201] Examples of the epoxy-unmodified rubber polymers include acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), hydrogenated nitrile rubber (HNBR), ethylene propylene rubber (EPDM), acrylic rubber (ACM), butyl rubber (IIR), butadiene rubber, and polyoxyalkylenes such as polypropylene oxide, polyethylene oxide, and polytetramethylene oxide. The epoxy-unmodified rubber polymers are preferably those having reactive groups such as amino groups, hydroxyl groups, or carboxyl groups at their ends. Among these epoxy-unmodified rubber polymers, NBR and polyoxyalkylenes are preferred from the viewpoint of the adhesion (adhesive strength) and impact resistance of the resulting cured product, NBR is more preferred, and NBR (CTBN) having carboxyl group ends is particularly preferred.

[0202] The glass transition temperature (Tg) of the epoxy unmodified rubber polymer is not particularly limited. The Tg of the epoxy unmodified rubber polymer is preferably -25°C or lower, more preferably -35°C or lower, even more preferably -40°C or lower, and particularly preferably -50°C or lower. This configuration has the advantage that the cured product has superior adhesive strength and impact resistance.

[0203] The number-average molecular weight of the epoxy-unmodified rubber polymer is preferably 1,500 to 40,000, more preferably 3,000 to 30,000, and particularly preferably 4,000 to 20,000, as measured by GPC in terms of polystyrene-equivalent molecular weight. This configuration has the advantage that the resulting curable resin composition has excellent adhesion (adhesion strength) and workability. The molecular weight distribution (ratio of weight-average molecular weight to number-average molecular weight (weight-average molecular weight / number-average molecular weight)) of the epoxy-unmodified rubber polymer is preferably 1.0 to 4.0, more preferably 1.2 to 3.0, and particularly preferably 1.5 to 2.5. This configuration has the advantage that the resulting curable resin composition has excellent workability.

[0204] Epoxy unmodified rubber polymers can be used individually or in combination of two or more types.

[0205] The amount (content) of the unmodified epoxy rubber polymer in this curable resin composition 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, per 100 parts by weight of epoxy resin (A). An amount of 1 part by weight or more provides good improvements in toughness, impact resistance, and adhesion, while an amount of 50 parts by weight or less results in a higher elastic modulus of the resulting cured product.

[0206] <Inorganic filler> The curable resin composition of one embodiment of the present invention may contain an inorganic filler. As the inorganic filler, for example, silicic acid and / or silicates can be used. Specific examples of silicic acid and silicates include dry silica, wet silica, aluminum silicate, magnesium silicate, calcium silicate, wollastonite, talc, and the like.

[0207] The dry silica mentioned above is also called fumed silica, and includes hydrophilic fumed silica with no surface treatment, and hydrophobic fumed silica produced by chemically treating the silanol group portion of hydrophilic fumed silica with silane and / or siloxane. As the dry silica, hydrophobic fumed silica is preferred in terms of dispersibility in component (A).

[0208] Other substances besides silicic acid and silicates may be used as inorganic fillers. Examples of inorganic fillers other than silicic acid and silicates include reinforcing fillers such as dolomite and carbon black; heavy calcium carbonate; colloidal calcium carbonate; magnesium carbonate; titanium dioxide; ferric oxide; aluminum powder; zinc oxide; activated zinc oxide, etc.

[0209] It is preferable that the inorganic filler is surface-treated with a surface treatment agent. Surface treatment improves the dispersibility of the inorganic filler in the curable resin composition, and as a result, the various physical properties of the resulting cured product are improved.

[0210] Inorganic fillers may be used individually or in combination of two or more types.

[0211] The amount (content) of inorganic filler used in this curable resin composition is preferably 1 to 200 parts by weight, more preferably 5 to 150 parts by weight, even more preferably 10 to 100 parts by weight, and particularly preferably 20 to 70 parts by weight, per 100 parts by weight of component (A).

[0212] <Calcium oxide> The curable resin composition of one embodiment of the present invention may contain calcium oxide.

[0213] When this curable resin composition contains calcium oxide, the calcium oxide in the curable resin composition reacts with the moisture in the curable resin composition to remove moisture, thereby solving various physical property problems caused by the presence of moisture. For example, the calcium oxide in the curable resin composition functions as an anti-bubble agent by removing moisture, and can suppress a decrease in the adhesive strength of the cured product.

[0214] Calcium oxide can be surface-treated with a surface treatment agent. Surface treatment improves the dispersibility of calcium oxide in the curable resin composition. As a result, the physical properties of the resulting cured product, such as adhesive strength, are improved compared to when untreated calcium oxide is used. When the curable resin composition contains surface-treated calcium oxide, the T-peel adhesion and impact-resistant peel adhesion of the cured product are particularly significantly improved. The surface treatment agent is not particularly limited, but fatty acids are preferred.

[0215] The amount (content) of calcium oxide used in this curable resin composition is preferably 0.1 to 10 parts by weight, more preferably 0.2 to 5 parts by weight, even more preferably 0.5 to 3 parts by weight, and particularly preferably 1 to 2 parts by weight, per 100 parts by weight of component (A). When the calcium oxide content in the curable resin composition is (a) 0.1 parts by weight or more per 100 parts by weight of component (A), the water removal effect from the curable resin composition is good, and when it is (b) 10 parts by weight or less, the strength of the resulting cured product is high.

[0216] Calcium oxide may be used alone or in combination of two or more types.

[0217] <Radical-curing resin> The curable resin composition of one embodiment of the present invention may optionally contain a radical curable resin having two or more double bonds in its molecule. In addition, the curable resin composition of one embodiment of the present invention may optionally further contain a low molecular weight compound having at least one double bond in its molecule and a molecular weight of less than 300, in addition to the radical curable resin. The low molecular weight compound, when used in combination with the radical curable resin, has the function of adjusting the viscosity, physical properties of the cured product, and curing rate, and functions as a so-called reactive diluent for the radical curable resin. Furthermore, a radical polymerization initiator may be added to the curable resin composition of one embodiment of the present invention. Here, the radical polymerization initiator is preferably of a latent type that is activated when the temperature is raised (preferably to about 50°C to about 150°C).

[0218] Examples of the radical-curable resin include unsaturated polyester resins, polyester (meth)acrylates, epoxy (meth)acrylates, urethane (meth)acrylates, polyether (meth)acrylates, and acrylic (meth)acrylates. These may be used individually or in combination of two or more. Specific examples of the radical-curable resin include the compounds described in International Publication No. 2014-115778. Specific examples of the low-molecular-weight compound and the radical polymerization initiator include the compounds described in International Publication No. 2014-115778.

[0219] As described in International Publication No. 2010-019539, if the radical polymerization initiator is activated at a temperature different from the curing temperature of the epoxy resin, selective polymerization of the radical-curable resin enables partial curing of the curable resin composition. This partial curing increases the viscosity of the curable resin composition after application, improving its wash-off resistance. In the water-washing shower process in manufacturing lines for vehicles and the like, the uncured curable resin composition may partially dissolve, scatter, or deform due to the water pressure during the showering process, adversely affecting the corrosion resistance of the coated steel plate or reducing the rigidity of the steel plate. The term "wash-off resistance" refers to resistance to this problem. Furthermore, this partial curing provides a function of temporarily fixing (temporarily bonding) the substrates together until the composition is fully cured. Therefore, the radical polymerization initiator is preferably activated by heating to 80°C to 130°C, and more preferably activated by heating to 100°C to 120°C.

[0220] <Monoepoxide> The curable resin composition of one embodiment of the present invention may optionally contain a monoepoxide. The monoepoxide may function as a reactive diluent. Specific examples of monoepoxides include aliphatic glycidyl ethers such as butyl glycidyl ether; aromatic glycidyl ethers such as phenyl glycidyl ether and cresyl glycidyl ether; ethers consisting of an alkyl group with 8 to 10 carbon atoms and a glycidyl group, such as 2-ethylhexyl glycidyl ether; ethers consisting of a phenyl group with 6 to 12 carbon atoms and a glycidyl group that can be substituted with an alkyl group with 2 to 8 carbon atoms, such as p-tert butylphenyl glycidyl ether; ethers consisting of an alkyl group with 12 to 14 carbon atoms and a glycidyl group, such as dodecyl glycidyl ether; aliphatic glycidyl esters such as glycidyl (meth)acrylate and glycidyl maleate; glycidyl esters of aliphatic carboxylic acids with 8 to 12 carbon atoms, such as glycidyl versatate, glycidyl neodecanoate, and glycidyl laurate; and pt-butylbenzoate glycidyl ester.

[0221] When the curable resin composition contains monoepoxide, the amount (content) of monoepoxide used 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, per 100 parts by weight of component (A). When the monoepoxide content in the curable resin composition is (a) 0.1 parts by weight or more per 100 parts by weight of component (A), a good viscosity reduction effect is exhibited, and when it is (b) 20 parts by weight or less, the physical properties such as the adhesion (adhesion strength) of the cured product are good.

[0222] <Photopolymerization initiator> Furthermore, when a curable resin composition according to one embodiment of the present invention is photocured, the curable resin composition may contain a photopolymerization initiator. Examples of such photopolymerization initiators include (i) onium salts such as aromatic sulfonium salts and aromatic iodonium salts with anions (such as hexafluoroantimonate, hexafluorophosphate, and tetraphenylborate), (ii) aromatic diazonium salts with the anions, and (iii) photocationic polymerization initiators (photoacid generators) such as metallocene salts with the anions. These photopolymerization initiators may be used individually or in combination of two or more.

[0223] <Other ingredients> In one embodiment of the present invention, other components may be used as needed. Examples of other components include: blowing agents such as azotype chemical blowing agents and thermally expandable microballoons; fibrous pulps such as aramid pulp; colorants such as pigments and dyes; extender pigments; ultraviolet absorbers; antioxidants; stabilizers (gelling inhibitors); plasticizers; leveling agents; defoamers; silane coupling agents; antistatic agents; flame retardants; lubricants; viscosity reducers; low shrinkage agents; organic fillers; thermoplastic resins; desiccants; dispersants, etc.

[0224] <Method for producing curable resin compositions> In the case where the curable resin composition of one embodiment of the present invention contains an epoxy resin (A) which is a curable resin and a core-shell polymer as component (B), it is preferable that the composition is a composition in which cross-linked polymer particles (B) are dispersed in a primary particle state. In the case where the curable resin composition of one embodiment of the present invention contains an epoxy resin (A) which is a curable resin and a single-layer polymer as component (B), it is preferable that the composition is a composition in which cross-linked polymer particles (B) are dispersed in a primary particle state.

[0225] Various methods can be used to obtain a composition in which crosslinked polymer particles (B) are dispersed in a primary particle state, that is, a method for producing a curable resin composition according to one embodiment of the present invention. Examples of such production methods include contacting core-shell polymer particles or monolayer polymers obtained in an aqueous latex state with component (A) and then removing unwanted components such as water; or extracting the core-shell polymer particles or monolayer polymers into an organic solvent, mixing them with component (A), and then removing the organic solvent. Specifically, it is preferable to use the method described in International Publication No. 2005 / 028546 as the production method. More specifically, it is preferable that the curable resin composition be prepared by a production method comprising the following steps 1 to 3 in order: (1) A first step in which an aqueous latex containing crosslinked polymer particles (B) (specifically, a reaction mixture obtained after producing crosslinked polymer particles (B) (core-shell polymer particles or monolayer polymer) by emulsion polymerization) is mixed with an organic solvent having a solubility in water at 20°C of 5% by weight or more and 40% by weight or less, and then mixed with excess water to aggregate the crosslinked polymer particles (B); (2) A second step in which the aggregated crosslinked polymer particles (B) are separated and recovered from the liquid phase, and then mixed again with an organic solvent to obtain an organic solvent solution of the crosslinked polymer particles (B); and (3) A third step in which the organic solvent solution is further mixed with component (A), and the organic solvent is then removed from the organic solvent solution by distillation.

[0226] Component (A) is preferably liquid at 23°C, as this facilitates the third step. "Liquid at 23°C" means that its softening point is 23°C or lower, and that it exhibits fluidity at 23°C.

[0227] The composition obtained through the above steps 1 to 3, in which cross-linked polymer particles (B) are dispersed in component (A) in a primary particle state, is then mixed with additional component (A), and optionally with components (C), (D), (E), and other components. This yields a curable resin composition according to one embodiment of the present invention, in which cross-linked polymer particles (B) are dispersed in component (A) in a primary particle state.

[0228] On the other hand, powdered cross-linked polymer particles (B), obtained by solidifying by methods such as salting out and then drying, can be redispersed in component (A) using a disperser with high mechanical shear force, such as a three-roll paint mill, roll mill, or kneader. By redispersing such cross-linked polymer particles (B), a curable resin composition according to one embodiment of the present invention can be obtained. When redispersing using a disperser, applying mechanical shear force at a high temperature to the mixture of components (A) and (B) enables efficient dispersion of component (B). The temperature when (re)dispersing component (B) in component (A) is preferably 50 to 200°C, more preferably 70 to 170°C, even more preferably 80 to 150°C, and particularly preferably 90 to 120°C.

[0229] The curable resin composition according to one embodiment of the present invention can be used as a one-component curable resin composition that is sealed and stored after all components have been pre-mixed, and then cured by heating and / or light irradiation after application. Alternatively, a solution A may be prepared, mainly containing component (A), further containing component (B) and optionally component (C), and a solution B containing components (D) and (E), and further containing component (B) and / or component (C), may be prepared separately from solution A. The curable resin composition according to one embodiment of the present invention can also be used as a two-component or multi-component curable resin composition consisting of solution A and solution B. Specifically, solution A and solution B can be mixed before use. The curable resin composition according to one embodiment of the present invention is particularly beneficial when used as a one-component curable resin composition.

[0230] If the curable resin composition according to one embodiment of the present invention is a two-component or multi-component curable resin composition, then component (B) and component (C) may each be contained in at least one of either liquid A or liquid B, for example, they may be contained only in liquid A, or only in liquid B, or they may be contained in both liquid A and liquid B.

[0231] <Cured product> A cured product can be obtained by curing a curable resin composition according to one embodiment of the present invention. When the curable resin composition contains core-shell polymer particles as component (B), the cross-linked polymer particles (B) are uniformly dispersed in the cured product. According to this preferred embodiment, the curable resin composition has low viscosity, and the cured product can be obtained with good workability.

[0232] The Young's modulus (elastic modulus) of the cured product obtained by curing the curable resin composition of one embodiment of the present invention at 23°C is preferably 50 MPa or more, more preferably 100 MPa or more, even more preferably 200 MPa or more, and particularly preferably 500 MPa or more. If the Young's modulus is 50 MPa or more, the rigidity and adhesive strength required for a structural adhesive can be secured. When converting the Young's modulus to durometer A hardness, a Young's modulus of 50 MPa or more corresponds to a durometer A hardness of 95 or more.

[0233] The high-temperature modulus of a cured product obtained from a curable resin composition according to one embodiment of the present invention can be evaluated by the Young's modulus at 80°C and / or the storage modulus at 80°C.

[0234] The Young's modulus at 80°C of a cured product obtained by curing a curable resin composition according to one embodiment of the present invention is preferably 50 MPa or more, more preferably 100 MPa or more, even more preferably 200 MPa or more, and particularly preferably 500 MPa or more. If the Young's modulus is 50 MPa or more, the rigidity and adhesive strength required for a structural adhesive can be ensured even in a high-temperature environment.

[0235] Furthermore, since the cured product obtained by curing the curable resin composition of one embodiment of the present invention has high heat resistance, the cured product exhibits a sufficiently elastic response. Therefore, the storage modulus in tensile mode obtained by dynamic viscoelasticity measurement (frequency: 20 Hz) of the cured product can be used as an approximate value of Young's modulus.

[0236] Therefore, in other words, the storage modulus at 23°C of a cured product obtained by curing the curable resin composition of one embodiment of the present invention is preferably 50 MPa or more. The storage modulus (23°C) is more preferably 100 MPa or more, even more preferably 200 MPa or more, and particularly preferably 500 MPa or more. If the storage modulus (23°C) is 50 MPa or more, the rigidity and adhesive strength required for a structural adhesive can be secured. In this specification, the storage modulus is the value obtained by measurement at a frequency of 20 Hz by dynamic viscoelasticity measurement.

[0237] The storage modulus (at 80°C) of a cured product obtained by curing a curable resin composition according to one embodiment of the present invention is preferably 50 MPa or more, more preferably 100 MPa or more, even more preferably 200 MPa or more, and particularly preferably 500 MPa or more. If the storage modulus (at 80°C) is 50 MPa or more, the rigidity and adhesive strength required for a structural adhesive can be ensured even in a high-temperature environment.

[0238] A cured product obtained by curing a curable resin composition according to one embodiment of the present invention exhibits high damping performance, specifically a high loss tangent tanδ at 40°C. In other words, in this specification, the "vibration damping performance" of a cured product can be evaluated by its loss tangent (tanδ) at 40°C. That is, a cured product obtained by curing a curable resin composition according to one embodiment of the present invention can maintain a high loss tangent while suppressing a decrease in Young's modulus at high temperatures, in other words, while suppressing a decrease in storage modulus (stiffness) at high temperatures. At 40°C, it is preferable to satisfy tanδ≧0.06, more preferably tanδ≧0.08, even more preferably tanδ≧0.10, and particularly preferably tanδ≧0.12. Tanδ can be obtained by dynamic viscoelasticity measurement, and the frequency can be measured at, for example, 20Hz.

[0239] <Application Method> The curable resin composition of one embodiment of the present invention can be applied to a substrate by any method. According to a preferred embodiment, the curable resin composition can be applied at a low temperature of about room temperature, and if necessary, the curable resin composition can be heated before application. The curable resin composition of one embodiment of the present invention is particularly useful in methods in which the curable resin composition is heated before application because it has excellent storage stability.

[0240] The curable resin composition of one embodiment of the present invention can be extruded onto a substrate in a bead, monofilament, or swirl shape using a coating robot. Furthermore, the curable resin composition of one embodiment of the present invention can be applied using mechanical coating methods such as a caulking gun or other manual coating means. The curable resin composition can also be applied to the substrate using a jet spray method or a streaming method. The curable resin composition of one embodiment of the present invention can be applied to one or both substrates, the substrates can be brought into contact with each other so that the curable resin composition is positioned between them, and the curable resin composition can be cured in this state to join the two substrates. The viscosity of the curable resin composition is not particularly limited; however, for the extrusion bead method, a viscosity of approximately 150 Pa·s to 600 Pa·s at 45°C is preferred, for the swirl coating method, a viscosity of approximately 100 Pa·s at 45°C is preferred, and for the high-volume coating method using a high-speed flow device, a viscosity of approximately 20 Pa·s to 400 Pa·s at 45°C is preferred. When applying a curable resin composition according to one embodiment of the present invention while heated, the temperature of the heated curable resin composition is preferably 30°C to 80°C, more preferably 40°C to 70°C, and even more preferably 45°C to 60°C.

[0241] This section describes a case in which a curable resin composition according to one embodiment of the present invention is used as an adhesive (i.e., structural adhesive) for joining structural members of a vehicle or the like. In this case, the joint between members can be strengthened by applying the curable resin composition as a weld bond method and then performing spot welding as appropriate.

[0242] The spot joints in the weld bond method may be formed by welding. The spot joints in the weld bond method are not limited to welding; any point-like joint structure is acceptable, such as a mechanical joint like a self-piercing rivet (SPR). Furthermore, the joints may be made using adhesive alone, a combination of adhesive and spot welding, or a combination of adhesive and mechanical joining as appropriate.

[0243] The spacing between the spot joints is preferably 10 mm to 100 mm, more preferably 15 mm to 70 mm, and even more preferably 25 mm to 50 mm.

[0244] When using a curable resin composition according to one embodiment of the present invention as an adhesive for vehicles, increasing the thixotropy of the curable resin composition is effective in improving the "resistance to washing off." Generally, thixotropy is improved by thixotropic agents such as fumed silica and amide wax, but the lower the viscosity of the main component, the greater the improvement effect and the more workable the curable resin composition tends to be. The curable resin composition according to one embodiment of the present invention is preferable because it is easy to increase its thixotropy due to its low viscosity. A highly thixotropic curable resin composition can be adjusted to an applicable viscosity by heating.

[0245] When using a curable resin composition according to one embodiment of the present invention as a structural adhesive for joining structural members of vehicles, etc., it is preferable to adjust the viscosity characteristics of the curable resin composition with a thixotropic agent or the like. By adjusting the viscosity characteristics of the curable resin composition, the stringiness of the structural adhesive (curable resin composition) is reduced. Therefore, it is possible to apply the structural adhesive not only continuously in a bead shape, but also intermittently. The advantages of intermittently applying the adhesive in the weld bond method are that, as described in International Publication No. 2018-008741, the adhesive can be applied while avoiding areas where spot welding is performed, and it has the effect of suppressing the generation of smoke and / or combustion gases such as carbon dioxide due to the burning of the adhesive, and reducing the amount of adhesive used.

[0246] Furthermore, in order to improve the "resistance to washing off" mentioned above, it is preferable to incorporate a polymer compound having a crystalline melting point near the application temperature of the curable resin composition into the curable resin composition, as described in International Publication No. 2005-118734. The curable resin composition containing the polymer compound has low viscosity (easy to apply) at the application temperature and high viscosity at the temperature of the water shower process, thereby improving the "resistance to washing off". Examples of the polymer compound having a crystalline melting point near the application temperature include various polyester resins such as crystalline or semi-crystalline polyester polyols.

[0247] <Adhesive> An adhesive according to one embodiment of the present invention includes a curable resin composition according to one embodiment of the present invention. When using the curable resin composition of one embodiment of the present invention as an adhesive to bond various substrates together, for example, substrates such as wood, metal, plastic, and glass can be joined. It is preferable to use the curable resin composition of one embodiment of the present invention as an adhesive to join automotive parts. It is even more preferable to use the curable resin composition of one embodiment of the present invention as an adhesive to join automotive frames together or to join an automotive frame to other automotive parts. Examples of substrates include various plastic substrates such as steel materials like cold-rolled steel and hot-dip galvanized steel, aluminum materials like aluminum and coated aluminum, general-purpose plastics, engineering plastics, and composite materials such as CFRP and GFRP.

[0248] The cured product obtained by curing this curable resin composition has excellent vibration damping properties, and therefore this curable resin composition can be suitably used as a structural adhesive for weld bonds. That is, the structural adhesive for weld bonds according to one embodiment of the present invention includes the curable resin composition according to one embodiment of the present invention.

[0249] An adhesive containing a curable resin composition according to one embodiment of the present invention can be applied to one or both of two substrates, the two substrates can be brought into contact with each other so that the adhesive containing the curable resin composition according to one embodiment of the present invention is positioned between them, and the curable resin composition according to one embodiment of the present invention can be cured in that state, thereby joining the two substrates with a cured product according to one embodiment of the present invention in between. That is, one embodiment of the present invention provides a laminate comprising two substrates and an adhesive layer in which an adhesive containing a curable resin composition according to one embodiment of the present invention or a structural adhesive for weld bonds has been cured to join the two substrates.

[0250] The laminate according to one embodiment of the present invention can also be expressed as follows: A laminate comprising a first substrate, a cured product obtained by curing an adhesive containing the curable resin composition, and a second substrate, laminated in this order.

[0251] The curable resin composition of one embodiment of the present invention has excellent adhesive properties. Therefore, a laminate obtained by bonding multiple members, including an aluminum substrate, with the curable resin composition of one embodiment of the present invention sandwiched between them, and then curing the curable resin composition, is preferred because it exhibits high adhesive strength.

[0252] The curable resin composition of one embodiment of the present invention is suitable for bonding dissimilar substrates with different coefficients of thermal expansion because it has excellent toughness.

[0253] Furthermore, the curable resin composition of one embodiment of the present invention can also be used for bonding aerospace components, particularly exterior metal components.

[0254] Furthermore, the curable resin composition of one embodiment of the present invention can be used in the form of a film-like adhesive as described in WO2011 / 141148, WO2014 / 176512, WO2015 / 011686, WO2015 / 011687, and WO2017 / 176832, and is useful as a film-like adhesive having damping (vibration-damping) properties. Furthermore, the curable resin composition of one embodiment of the present invention can be used in the form of a filling and reinforcing material, particularly a foamed filling and reinforcing material, as described in JP-A-8-198995, WO2008 / 014053, WO2013 / 114195, and JP-A-2015-147928, and is useful as a filling and reinforcing material that fills and strengthens the closed cross-sectional structure described later and has damping (vibration-damping) properties.

[0255] <Curing temperature> The curing temperature of the curable resin composition of one embodiment of the present invention is not particularly limited, but is preferably 50°C to 250°C, more preferably 80°C to 220°C, even more preferably 100°C to 200°C, and particularly preferably 130°C to 180°C.

[0256] When using a curable resin composition according to one embodiment of the present invention as an automotive adhesive, it is preferable from the viewpoint of shortening and simplifying the process to apply the adhesive to an automotive component, then apply a coating such as electrodeposition paint, and cure the adhesive at the same time as the coating is baked and cured.

[0257] <Application area> When the curable resin composition of one embodiment of the present invention is used as a structural adhesive for joining structural members of a vehicle, it is useful for structural parts such as roof rails, floor frames, A-pillars (front pillars), B-pillars (center pillars), C-pillars, D-pillars, floor panels, rear floor panels, front side members, rear side members, side members, tunnel rains, floor cross members, wheelhouses, side sills, and outer sills, as well as for the hemming portions where the inner and outer panels of doors, hoods, and trunks meet.

[0258] Because the curable resin composition of one embodiment of the present invention has excellent damping (vibration damping) properties, when applied to the panel joints of vehicle body components between a component that receives vibration input due to road noise from a vehicle, etc., and the passenger compartment of the vehicle, it is effective in reducing vibration and noise levels inside the passenger compartment due to road noise, and improving quietness. Specifically, this applies to vibration transmission paths from the suspension to the passenger compartment, and more specifically, to parts described in Japanese Patent Application Publication No. 7-186656, such as the joint between the fender shield and the dash panel, the joint between the front side member and the dash panel, and the joint between the bracket supporting the upper end of the suspension coil spring and the spring house panel.

[0259] Because the curable resin composition of one embodiment of the present invention has excellent damping (vibration damping) properties, when applied to the panel joints of vehicle body components between a component that receives vibration input from engine noise of a vehicle, etc., and the passenger compartment of the vehicle, it is effective in reducing vibration and noise levels inside the passenger compartment caused by engine noise, and improving quietness. Specifically, this applies to the vibration transmission path from the engine to the passenger compartment, and more specifically, to joints around the engine mount, for example.

[0260] Because the curable resin composition of one embodiment of the present invention has excellent damping properties, it can be used as an adhesive for damping joint members forming a vehicle body structure as described in Japanese Patent Publication No. 2015-128942 and Japanese Patent Publication No. 2015-134536, and also as described in Japanese Patent Publication No. 2015-147501, Japanese Patent Publication No. 2018-184077, Japanese Patent Publication No. 2019-38926, and Japanese Patent Publication No. 20 It is useful as an adhesive for vehicle body components as described in Japanese Patent Publication No. 19-38364, Japanese Patent Publication No. 2019-98897, Japanese Patent Publication No. 2019-98901, Japanese Patent Publication No. 2019-98902, Japanese Patent Publication No. 2019-98907, Japanese Patent Publication No. 2019-98908, Japanese Patent Publication No. 2019-98909, and Japanese Patent Publication No. WO2015 / 119054, etc.

[0261] <Vehicle components with a closed cross-sectional structure> Another aspect of the present invention is a vehicle member having a closed cross-section structure, in which two or more base materials, each having a closed cross-section and a joining flange at its end, are joined together, wherein a curable resin composition according to one embodiment of the present invention is applied between the joining flanges of the two base materials as an adhesive or structural adhesive for weld bonding, and the adhesive is cured to join them.

[0262] A vehicle member according to one embodiment of the present invention can also be described as follows: A vehicle member having a closed cross-section structure, wherein two or more base materials, each having a closed cross-section and a joining flange at its end, are joined together, and an adhesive according to one embodiment of the present invention or a structural adhesive for weld bonds according to one embodiment of the present invention is applied between the joining flanges of the two base materials, and the adhesive is cured to join them.

[0263] In this specification, the term "joining flange portion" refers to a plate-shaped flange or lug (protrusion) provided at the ends of two or more base materials for reinforcing or connecting the joints between the base materials. The term "closed cross section portion" refers to the cross section of a hollow columnar member having a closed cross-sectional structure obtained by joining the flange portions, which are formed by joining two or more base materials, for example, two hat-shaped steel materials.

[0264] A vehicle component according to one embodiment of the present invention has a closed cross-section, which is formed by joining two or more base materials, each having a joining flange at its end, by curing an adhesive containing the curable resin composition. Specifically, the adhesive containing the curable resin composition is applied to the joining flange of at least one of the two or more base materials having a joining flange at its end, the joining flange of the other base material is bonded to the surface to which the adhesive is applied, and the adhesive is cured to join the two or more base materials. This makes it possible to form a vehicle component having a closed cross-section. In the closed cross-section, the laminated structure including the joining flanges of the two or more base materials and the cured product formed between the joining flanges is also referred to as a closed cross-section structure.

[0265] The cured product obtained by curing this curable resin composition or the adhesive according to one embodiment of the present invention exhibits high rigidity not only at room temperature but also in high-temperature environments such as 80°C. Therefore, even if the area of ​​the joint flange is reduced, sufficient rigidity can be maintained even in high-temperature environments, resulting in a lighter vehicle component. Furthermore, the cured product obtained by curing this curable resin composition or the adhesive according to one embodiment of the present invention exhibits high vibration damping properties. This reduces the transmission of vibrations such as road noise through the vehicle component, making it possible to reduce sound-absorbing and vibration-damping materials such as asphalt sheets used in the vehicle, which would otherwise increase weight, thus contributing to vehicle weight reduction. In addition, even if the base material used for the vehicle component is made thinner, the decrease in vibration damping due to the decrease in rigidity of the vehicle component can be compensated for by the high vibration damping properties of the cured product obtained by curing the adhesive. Thus, it is possible to achieve both excellent vibration damping and vehicle weight reduction.

[0266] <Application> The curable resin composition of one embodiment of the present invention is preferably used in applications such as structural adhesives for vehicles and aircraft, structural adhesives for wind power generation, paints, lamination materials with glass fibers, printed circuit board materials, solder resists, interlayer insulating films, build-up materials, adhesives for FPCs, electrical insulating materials such as encapsulants for semiconductors and LEDs, die bond materials, underfills, semiconductor mounting materials such as ACF, ACP, NCF, and NCP, and encapsulants for display and lighting equipment such as liquid crystal panels, OLED lighting, and OLED displays. In particular, it is useful as a structural adhesive for weld bonds.

[0267] One embodiment of the present invention may relate to the following: A curable resin composition comprising 100 parts by weight of epoxy resin (A) and 1 to 100 parts by weight of crosslinked polymer particles (B), wherein the crosslinked polymer particles (B) are one or more crosslinked polymer particles selected from the crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3) described in (1) to (3) below; (1) The crosslinked polymer particles (B-1) have a core-shell structure and / or a monolayer structure including a core layer and a shell layer, wherein the core layer and / or the monolayer is a (meth)acrylate polymer (M-1) obtained by polymerizing a monomer mixture (m-1) containing 0.1% to 10% by weight of a crosslinkable monomer, and having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and containing 60% by weight or more of (M-1) relative to the total amount of (B-1), and the shell layer is a (meth)acrylate polymer (M-1') obtained by graft polymerization of the monomer mixture (m-1') onto the core layer. (2) The crosslinked polymer particles (B-2) have a core-shell structure comprising a core layer and a shell layer, wherein the core layer is a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) that does not contain crosslinkable monomers, and has a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the shell layer is a (meth)acrylate polymer (M-2') obtained by graft polymerization of a monomer mixture (m-2') containing 1% to 100% by weight of crosslinkable monomers onto the core layer. (3) The crosslinked polymer particles (B-3) have a core-shell structure including a core layer and a shell layer, wherein the shell layer is a (meth)acrylate polymer (M-3') having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the content of the shell layer relative to the total amount of the crosslinked polymer particles (B-3) is 30% to 90% by weight.

[0268] It is preferable to use a curable resin composition in which the Young's modulus of the cured product obtained by curing the aforementioned curable resin composition is 50 MPa or more at 23°C.

[0269] It is preferable to use a curable resin composition in which the epoxy resin (A) contains epoxy resin (A1) having an epoxy equivalent of 90 g / eq or more and less than 200 g / eq, and the content of component (A1) in the total amount of component (A) is 25% by weight or more.

[0270] It is preferable to use a curable resin composition in which the epoxy resin (A) contains a bisphenol A type epoxy resin and / or a bisphenol F type epoxy resin (A2), and the content of the component (A2) in the total amount of the component (A) is 25% by weight or more.

[0271] It is preferable to use a curable resin composition in which the crosslinked polymer particles (B-1) are single-layer crosslinked polymer particles composed only of the (meth)acrylate polymer (M-1).

[0272] It is preferable to use a curable resin composition in which the content of the core layer of the crosslinked polymer particles (B-2) is 50 parts by weight or more and 95 parts by weight or less with respect to the total amount of the crosslinked polymer particles (B-2).

[0273] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-3') in the crosslinked polymer particles (B-3) is obtained by polymerizing a monomer mixture (m-3') having a crosslinkable monomer content of 0.0% by weight or more and 2.0% by weight or less.

[0274] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-3') is obtained by polymerizing a monomer mixture (m-3'-a) that does not contain a crosslinkable monomer.

[0275] It is preferable to use a curable resin composition in which the content of epoxy groups in the (meth)acrylate polymer (M-3') is 0.0 mmol / g or more and 2.0 mmol / g or less with respect to the total amount of (M-3').

[0276] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-3') does not contain an epoxy group.

[0277] It is preferable to use a curable resin composition in which the crosslinked polymer particles (B-3) have one or more crosslinked core layers selected from the group consisting of a diene polymer, a (meth)acrylate polymer (M-3), and an organosiloxane polymer.

[0278] It is preferable to use a curable resin composition in which the core layer of the crosslinked polymer particles (B-3) is a (meth)acrylate polymer (M-3-a) obtained by polymerizing a monomer mixture (m-3-a) containing 0.1% to 10% by weight of a crosslinkable monomer.

[0279] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-3-a) is a (meth)acrylate polymer (M-3-b) having a glass transition temperature of -20°C to 30°C as determined by the Fox formula.

[0280] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-1' and / or M-2') is a (meth)acrylate polymer (M-1'-a and / or M-2'-a) having a glass transition temperature of -20°C or higher and 30°C or lower as determined by the Fox formula.

[0281] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-1 to M-3) is obtained by polymerizing a monomer mixture (m-1 to M-3) having a styrene monomer content of 10% to 70% by weight.

[0282] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-1 to M-3) is obtained by polymerizing a monomer mixture (m-1 to M-3) having a content of 50% to 90% by weight of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms.

[0283] It is preferable to use a curable resin composition in which the (meth)acrylate polymer (M-1'~3') is a (meth)acrylate polymer (M-1'~3') obtained by polymerizing a monomer mixture (m-1'~3') having a content of 70% to 100% by weight of alkyl (meth)acrylate having 1 or 2 carbon atoms.

[0284] It is preferable to use a curable resin composition that further contains 1 to 50 parts by mass of blocked urethane (C) per 100 parts by mass of epoxy resin (A).

[0285] It is preferable to use a curable resin composition that further contains 1 to 80 parts by mass of epoxy curing agent (D) per 100 parts by mass of epoxy resin (A).

[0286] It is preferable to use a curable resin composition that further contains 0.1 to 10.0 parts by mass of a curing accelerator (E) per 100 parts by mass of the epoxy resin (A).

[0287] It is preferable to use a cured product obtained by curing the aforementioned curable resin composition.

[0288] It is preferable to use an adhesive containing the aforementioned curable resin composition.

[0289] It is preferable to use a structural adhesive for weld bonding that contains the aforementioned curable resin composition.

[0290] It is preferable to use a laminate comprising two substrates and a hardened adhesive layer of the adhesive that joins the two substrates.

[0291] It is preferable to use a vehicle component in which two or more base materials, each having a closed cross-section and a joining flange at its end, are joined together, and the vehicle component has a closed cross-section structure in which the adhesive is applied between the joining flanges of the two base materials and then cured to join them.

[0292] [1] A curable resin composition containing 100 parts by weight of epoxy resin (A) and 1 to 100 parts by weight of crosslinked polymer particles (B), The aforementioned crosslinked polymer particles (B) comprise one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3) described in (1) to (3) below, and the curable resin composition; (1) The crosslinked polymer particles (B-1) have a core-shell structure or a single-layer structure including a core layer and a shell layer. The core layer and / or the single layer include a (meth)acrylate polymer (M-1) obtained by polymerizing a monomer mixture (m-1) containing 0.1 wt% or more and 10 wt% or less of a crosslinkable monomer, and having a glass transition temperature of -20°C or more and 30°C or less determined by the Fox equation. The (meth)acrylate polymer (M-1) is contained in an amount of 60 wt% or more based on the total amount of (B-1). The shell layer includes a (meth)acrylate polymer (M-1') obtained by graft-polymerizing a monomer mixture (m-1') onto the core layer. (2) The crosslinked polymer particles (B-2) have a core-shell structure including a core layer and a shell layer. The core layer includes a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) not containing a crosslinkable monomer, and having a glass transition temperature of -20°C or more and 30°C or less determined by the Fox equation. The shell layer includes a (meth)acrylate polymer (M-2') obtained by graft-polymerizing a monomer mixture (m-2') containing 1 wt% or more and 100 wt% or less of the crosslinkable monomer onto the core layer. (3) The crosslinked polymer particles (B-3) have a core-shell structure including a core layer and a shell layer. The shell layer includes a (meth)acrylate polymer (M-3') having a glass transition temperature of -20°C or more and 30°C or less determined by the Fox equation. The content of the shell layer based on the total amount of the crosslinked polymer particles (B-3) is 30 wt% or more and 90 wt% or less. <000​​​​​​​​​[4] The curable resin composition according to any one of [1] to [3], wherein the epoxy resin (A) contains epoxy resin (A1) having an epoxy equivalent of 90 g / eq or more and less than 200 g / eq, and the content of epoxy resin (A1) in the total amount of epoxy resin (A) is 25% by weight or more.

[0296] [5] The curable resin composition according to any one of [1] to [4], wherein the epoxy resin (A) contains a bisphenol A type epoxy resin (A2) and / or a bisphenol F type epoxy resin (A2), and the content of the bisphenol A type epoxy resin (A2) and the bisphenol F type epoxy resin (A2) in the total amount of the epoxy resin (A) is 25% by weight or more.

[0297] [6] The curable resin composition according to any one of [1] to [5], wherein the crosslinked polymer particles (B-1) are single-layer crosslinked polymer particles composed solely of the (meth)acrylate polymer (M-1).

[0298] [7] The curable resin composition according to any one of [1] to [6], wherein the content of the crosslinked polymer particles (B-2) in the core layer is 50 parts by weight or more and 95 parts by weight or less relative to the total amount of the crosslinked polymer particles (B-2).

[0299] [8] The curable resin composition according to any one of [1] to [7], wherein the (meth)acrylate polymer (M-3') in the crosslinked polymer particles (B-3) includes a polymer obtained by polymerizing a monomer mixture (m-3') having a crosslinkable monomer content of 0.0% by weight or more and 2.0% by weight or less.

[0300] [9] The curable resin composition according to [8], wherein the (meth)acrylate polymer (M-3') comprises a polymer obtained by polymerizing a monomer mixture (m-3'-a) that does not contain a crosslinkable monomer.

[0301]

[10] The curable resin composition according to any one of [1] to [9], wherein the content of epoxy groups in the (meth)acrylate polymer (M-3') is 0.0 mmol / g or more and 2.0 mmol / g or less relative to the total amount of (M-3').

[0302]

[11] The curable resin composition according to

[10] , wherein the (meth)acrylate polymer (M-3') does not contain an epoxy group.

[0303]

[12] The curable resin composition according to any one of [1] to

[11] , wherein the crosslinked polymer particles (B-3) have one or more core layers selected from the group consisting of diene polymers, (meth)acrylate polymers (M-3), and organosiloxane polymers.

[0304]

[13] The curable resin composition according to

[12] , wherein the core layer of the crosslinked polymer particles (B-3) comprises a (meth)acrylate polymer (M-3-a) obtained by polymerizing a monomer mixture (m-3-a) containing 0.1% to 10% by weight of a crosslinkable monomer.

[0305]

[14] The curable resin composition according to

[13] , wherein the (meth)acrylate polymer (M-3-a) comprises a (meth)acrylate polymer (M-3-b) having a glass transition temperature of -20°C or higher and 30°C or lower as determined by the Fox formula.

[0306]

[15] The curable resin composition according to any one of [1] to [5] and [7], wherein the (meth)acrylate polymer (M-1' and / or M-2') is a (meth)acrylate polymer (M-1'-a and / or M-2'-a) having a glass transition temperature of -20°C or higher and 30°C or lower as determined by the Fox formula.

[0307]

[16] The curable resin composition according to any one of [1] to

[15] , wherein the (meth)acrylate polymer (M-1) is a (meth)acrylate polymer (M-1) obtained by polymerizing a monomer mixture (m-1) having a styrene monomer content of 10% by weight or more and 70% by weight or less.

[0308]

[17] The curable resin composition according to any one of [1] to

[16] , wherein the (meth)acrylate polymer (M-2) is a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) having a styrene monomer content of 10% by weight or more and 70% by weight or less.

[0309]

[18] The curable resin composition according to any one of [1] to

[17] , wherein the (meth)acrylate polymer (M-3) is a (meth)acrylate polymer (M-3) obtained by polymerizing a monomer mixture (m-3) having a styrene monomer content of 10% by weight or more and 70% by weight or less.

[0310]

[19] The curable resin composition according to any one of [1] to

[18] , wherein the (meth)acrylate polymer (M-1) is a (meth)acrylate polymer (M-1) obtained by polymerizing a monomer mixture (m-1) having a content of 50% by weight or more and 90% by weight or less of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms.

[0311]

[20] The curable resin composition according to any one of [1] to

[19] , wherein the (meth)acrylate polymer (M-2) is a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) having a content of 50% by weight or more and 90% by weight or less of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms.

[0312]

[21] The curable resin composition according to any one of [1] to

[20] , wherein the (meth)acrylate polymer (M-3) is a (meth)acrylate polymer (M-3) obtained by polymerizing a monomer mixture (m-3) having a content of 50% by weight or more and 90% by weight or less of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms.

[0313]

[22] The curable resin composition according to any one of [1] to

[21] , wherein the (meth)acrylate polymer (M-1') is a (meth)acrylate polymer (M-1') obtained by polymerizing a monomer mixture (m-1') having a carbon-1 or carbon-2 alkyl (meth)acrylate content of 70% by weight or more and 100% by weight or less.

[0314]

[23] The curable resin composition according to any one of [1] to

[22] , wherein the (meth)acrylate polymer (M-2') is a (meth)acrylate polymer (M-2') obtained by polymerizing a monomer mixture (m-2') having a carbon-1 or carbon-2 alkyl (meth)acrylate content of 70% by weight or more and 100% by weight or less.

[0315]

[24] The curable resin composition according to any one of [1] to

[23] , wherein the (meth)acrylate polymer (M-3') is a (meth)acrylate polymer (M-3') obtained by polymerizing a monomer mixture (m-3') having a carbon-1 or carbon-2 alkyl (meth)acrylate content of 70% by weight or more and 100% by weight or less.

[0316]

[25] A curable resin composition according to any one of [1] to

[24] , further comprising 1 to 50 parts by mass of blocked urethane (C) per 100 parts by mass of epoxy resin (A).

[0317]

[26] A curable resin composition according to any one of [1] to

[25] , further comprising 1 to 80 parts by mass of epoxy curing agent (D) per 100 parts by mass of epoxy resin (A).

[0318]

[27] A curable resin composition according to any one of [1] to

[26] , further comprising 0.1 to 10.0 parts by mass of a curing accelerator (E) per 100 parts by mass of the epoxy resin (A).

[0319] A cured product obtained by curing a curable resin composition described in any one of

[28] [1] to

[27] .

[0320] An adhesive comprising a curable resin composition as described in any one of

[29] [1] to

[27] .

[0321] A structural adhesive for weld bonds comprising a curable resin composition as described in any one of

[30] [1] to

[27] .

[0322]

[31] A laminate comprising two substrates and an adhesive layer formed by curing the adhesive described in

[29] or the structural adhesive for weld bonding described in

[30] , which joins the two substrates.

[0323]

[32] A vehicle member having a closed cross-section structure, wherein two or more base materials are joined together, each having a closed cross-section and a joining flange at its end, and the adhesive described in

[29] or the structural adhesive for weld bonds described in

[30] is applied between the joining flanges of the two base materials, and the adhesive is cured to join them. [Examples]

[0324] An embodiment of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0325] (Measurement of volume-average particle diameter) The volume-average particle size (Mv) of the cross-linked polymer particles dispersed in the aqueous latex described in the manufacturing example was measured using a Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.). The sample used for measurement was diluted with deionized water. The measurement was performed by inputting the refractive index of water and the refractive index of each cross-linked polymer particle, adjusting the sample concentration so that the signal level was within the range of 0.6 to 0.8, with a measurement time of 600 seconds.

[0326] 1. Preparation of crosslinked polymer particles Manufacturing Example 1-1: Preparation of Core-Shell Polymer Latex (L-1) Into a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and an apparatus for adding monomers and an emulsifier, 182 parts by weight of deionized water, 0.006 parts by weight of disodium ethylenediaminetetraacetate (EDTA), 0.0015 parts by weight of ferrous sulfate heptahydrate (FE), 0.6 parts by weight of sodium formaldehyde sulfoxylate (SFS), and 0.01 parts by weight of sodium dodecylbenzenesulfonate (SDS) were charged, and the temperature was raised to 60 °C while stirring in a nitrogen stream. Next, a mixture of core layer monomers (47 parts by weight of methyl methacrylate (MMA), 40 parts by weight of butyl acrylate (BA), 0.43 parts by weight of allyl methacrylate (ALMA)), and 0.13 parts by weight of cumene hydroperoxide (CHP) was added dropwise over 3 hours. Also, together with the addition of the above monomer mixture, 20 parts by weight of a 5 wt% aqueous solution of SDS was continuously added over 3 hours. Stirring was continued for 1 hour after the addition of the monomer mixture was completed to complete the polymerization, and a latex containing acrylic polymer particles was obtained. Subsequently, a mixture of graft monomers (9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of glycidyl methacrylate (GMA), 1.3 parts by weight of ALMA), and 0.07 parts by weight of CHP was continuously added thereto over 120 minutes. After the addition was completed, 0.07 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, and a latex (L-1) containing a core-shell polymer was obtained. The polymerization conversion rate of the monomer component was 99% or more. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.36 μm.

[0327] Production Example 1-2; Preparation of Core-Shell Polymer Latex (L-2) In Production Example 1-1, a latex (L-2) of a core-shell polymer was obtained in the same manner as in Production Example 1-1, except that <45 parts by weight of MMA, 42 parts by weight of methoxyethyl acrylate (MEA), 0.43 parts by weight of ALMA> was used as the core layer monomer instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA>. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0328] Production Example 1-3; Preparation of Core-Shell Polymer Latex (L-3) In Production Example 1-1, except that <9 parts by weight of BA, 78 parts by weight of butyl methacrylate (BMA), 0.43 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, a latex (L-3) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0329] Production Example 1-4; Preparation of Core-Shell Polymer Latex (L-4) In Production Example 1-1, <45 parts by weight of MMA, 42 parts by weight of MEA, 0.43 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, and <4.7 parts by weight of MMA, 6 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers. Except for this, a latex (L-4) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm. <s

[0330] Production Example 1-5; Preparation of Core-Shell Polymer Latex (L-5) In Production Example 1-1, <47 parts by weight of MMA, 40 parts by weight of BA, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers. Except for this, a latex (L-5) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.37 μm.

[0331] Production Example 1-6; Preparation of Core-Shell Polymer Latex (L-6) In Production Example 1-1, <45 parts by weight of MMA, 42 parts by weight of MEA, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, it was the same as in Production Example 1-1 to obtain a latex (L-6) of the core-shell polymer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.29 μm.

[0332] Production Example 1-7; Preparation of Core-Shell Polymer Latex (L-7) In Production Example 1-1, the SDS initially charged was changed to 0.4 parts by mass instead of 0.01 parts by mass, <47 parts by weight of MMA, 40 parts by weight of BA, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, it was the same as in Production Example 1-1 to obtain a latex (L-7) of the core-shell polymer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.10 μm.

[0333] Production Example 1-8; Preparation of Core-Shell Polymer Latex (L-8) In Production Example 1-1, the SDS initially charged was changed to 0.1 parts by mass instead of 0.01 parts by mass, <47 parts by weight of MMA, 40 parts by weight of BA, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, it was the same as in Production Example 1-1 to obtain a latex (L-8) of the core-shell polymer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.17 μm.

[0334] Production Example 1-9; Preparation of Core-Shell Polymer Latex (L-9) In Production Example 1-1, the SDS initially charged was changed from 0.01 part by mass to 0.1 part by mass, and <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 part by weight of ALMA> was used as the core layer monomer instead of <47 parts by weight of MMA, 40 parts by weight of BA, 4.3 parts by weight of ALMA>, and <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was used as the graft monomer instead of <6 parts by weight of MMA, 6 parts by weight of BA, 1 part by weight of GMA>. Otherwise, the same procedure as in Production Example 1-1 was followed to obtain a core-shell polymer latex (L-9). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.18 μm.

[0335] Production Example 1-10; Preparation of Core-Shell Polymer Latex (L-10) In Production Example 1-1, the SDS initially charged was changed from 0.01 part by mass to 0.1 part by mass, and <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 part by weight of ALMA> was used as the core layer monomer instead of <47 parts by weight of MMA, 40 parts by weight of BA, 2.1 parts by weight of ALMA>, and <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was used as the graft monomer instead of <6 parts by weight of MMA, 6 parts by weight of BA, 1 part by weight of GMA>. Otherwise, the same procedure as in Production Example 1-1 was followed to obtain a core-shell polymer latex (L-10). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.18 μm.

[0336] Production Example 1-11; Preparation of Core-Shell Polymer Latex (L-11) In Production Example 1-1, except that the SDS initially charged was changed from 0.01 part by mass to 0.1 part by mass, <BA 9 parts by weight, BMA 78 parts by weight, ALMA 2.1 parts by weight> was used instead of <MMA 47 parts by weight, BA 40 parts by weight, ALMA 0.43 parts by weight> as the core layer monomer, and <MMA 6 parts by weight, BA 6 parts by weight, GMA 1 part by weight> was used instead of <MMA 9.5 parts by weight, BA 1.2 parts by weight, GMA 1 part by weight, ALMA 1.3 parts by weight> as the graft monomer, a latex (L-11) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.17 μm.

[0337] Production Example 1-12; Preparation of Core-Shell Polymer Latex (L-12) In Production Example 1-1, except that <MMA 15 parts by weight, BA 72 parts by weight, ALMA 0.43 parts by weight> was used instead of <MMA 47 parts by weight, BA 40 parts by weight, ALMA 0.43 parts by weight> as the core layer monomer, and <MMA 9.5 parts by weight, BA 2.5 parts by weight, GMA 1 part by weight> was used instead of <MMA 9.5 parts by weight, BA 1.2 parts by weight, GMA 1 part by weight, ALMA 1.3 parts by weight> as the graft monomer, a latex (L-12) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0338] Production Example 1-13; Preparation of Core-Shell Polymer Latex (L-13) In Production Example 1-1, except that <MMA 72 parts by weight, BA 15 parts by weight, ALMA 0.43 parts by weight> was used instead of <MMA 47 parts by weight, BA 40 parts by weight, ALMA 0.43 parts by weight> as the core layer monomer, and <MMA 9.5 parts by weight, BA 2.5 parts by weight, GMA 1 part by weight> was used instead of <MMA 9.5 parts by weight, BA 1.2 parts by weight, GMA 1 part by weight, ALMA 1.3 parts by weight> as the graft monomer, a latex (L-13) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0339] Production Example 1-14; Preparation of Core-Shell Polymer Latex (L-14) In Production Example 1-1, except that <72 parts by weight of MMA, 15 parts by weight of BA, 0.43 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, a latex (L-14) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0340] Production Example 1-15; Preparation of Core-Shell Polymer Latex (L-15) In Production Example 1-1, <50 parts by weight of MMA, 37 parts by weight of BMA, 0.43 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, and <2 parts by weight of MMA, 8.7 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers. Except for this, a latex (L-15) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.34 μm.

[0341] Production Example 1-16; Preparation of Core-Shell Polymer Latex (L-16) In Production Example 1-1, except that <72 parts by weight of MMA, 15 parts by weight of MEA, 0.43 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, a latex (L-16) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0342] Production Example 1-17; Preparation of Core-Shell Polymer Latex (L-17) In Production Example 1-1, except that <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> was replaced with <47 parts by weight of MMA, 40 parts by weight of BA, 12.9 parts by weight of ALMA> as the core layer monomer and <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was replaced with <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> as the graft monomer, a latex (L-17) of a core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0343] Production Example 1-18; Preparation of Core-Shell Polymer Latex (L-18) In Production Example 1-1, except that <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> was replaced with <45 parts by weight of MMA, 42 parts by weight of MEA> as the core layer monomer and <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was replaced with <4.7 parts by weight of MMA, 6 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer, a latex (L-18) of a core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0344] Production Example 1-19; Preparation of Core-Shell Polymer Latex (L-19) In Production Example 1-1, except that <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> was replaced with <45 parts by weight of MMA, 42 parts by weight of MEA> as the core layer monomer and <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> was replaced with <1.7 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA, 0.3 parts by weight of ALMA> as the graft monomer, a latex (L-19) of a core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.34 μm.

[0345] Production Example 1-20; Preparation of Core-Shell Polymer Latex (L-20) In Production Example 1-1, <45 parts by weight of MMA, 42 parts by weight of MEA, 0.87 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <1.7 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA, 0.3 parts by weight of ALMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, in the same manner as in Production Example 1-1, a latex (L-20) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0346] Production Example 1-21; Preparation of Core-Shell Polymer Latex (L-21) In Production Example 1-1, <45 parts by weight of MMA, 42 parts by weight of MEA, 1.74 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <1.7 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA, 0.3 parts by weight of ALMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, in the same manner as in Production Example 1-1, a latex (L-21) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.32 μm.

[0347] Production Example 1-22; Preparation of Core-Shell Polymer Latex (L-22) In Production Example 1-1, <45 parts by weight of MMA, 42 parts by weight of MEA, 0.87 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer. Otherwise, the latex (L-22) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0348] Production Example 1-23; Preparation of Core-Shell Polymer Latex (L-23) 182 parts by weight of deionized water, 0.006 parts by weight of EDTA, 0.0015 parts by weight of FE, 1.5 parts by weight of SFS and 0.01 parts by weight of SDS were charged into a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and a monomer and emulsifier addition device, and the temperature was raised to 60°C while stirring in a nitrogen stream. Next, a mixture of the core layer monomer (8 parts by weight of MMA, 40 parts by weight of BA, 2.4 parts by weight of ALMA) and 0.07 parts by weight of CHP was added dropwise over 2 hours. Also, 20 parts by weight of a 5 wt% aqueous solution of SDS was continuously added over 2 hours along with the addition of the monomer mixture. Stirring was continued for 1 hour after the addition of the monomer mixture was completed to complete the polymerization, and a latex containing acrylic polymer particles was obtained. Subsequently, a mixture of the graft monomer (8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA) and 0.23 parts by weight of CHP was continuously added thereto over 2 hours. After the addition was completed, 0.07 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, and a latex (L-23) containing a core-shell polymer was obtained. The polymerization conversion rate of the monomer component was 99% or more. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.34 μm.

[0349] Production Example 1-24; Preparation of Core-Shell Polymer Latex (L-24) In Production Example 1-23, instead of <8 parts by weight of MMA, 40 parts by weight of BA, 2.4 parts by weight of ALMA> as the core layer monomer, <24 parts by weight of MMA, 24 parts by weight of BA, 2.4 parts by weight of ALMA> was used, and instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.23 parts by weight of CHP> as the graft monomer and its initiator (CHP), <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.94 parts by weight of CHP> was used. Otherwise, in the same manner as Production Example 1-23, a latex (L-24) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0350] Production Example 1-25; Preparation of Core-Shell Polymer Latex (L-25) Into a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and an apparatus for adding monomers and an emulsifier, 182 parts by weight of deionized water, 0.006 parts by weight of EDTA, 0.0015 parts by weight of FE, 1.5 parts by weight of SFS, and 0.01 parts by weight of SDS were charged, and the temperature was raised to 60 °C while stirring in a nitrogen stream. Next, a mixture of the core layer monomer (12 parts by weight of MMA, 12 parts by weight of BA, 1.2 parts by weight of ALMA) and 0.04 parts by weight of CHP was added dropwise over 1 hour. Also, along with the addition of the above monomer mixture, 20 parts by weight of a 5 wt% aqueous solution of SDS was continuously added over 1 hour. Stirring was continued for 1 hour after the addition of the monomer mixture was completed to complete the polymerization, and a latex containing acrylic polymer particles was obtained. Subsequently, a mixture of the graft monomer (38 parts by weight of MMA, 38 parts by weight of BA) and 0.46 parts by weight of CHP was continuously added thereto over 3 hours. After the addition was completed, 0.07 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, and a latex (L-25) containing a core-shell polymer was obtained. The polymerization conversion rate of the monomer components was 99% or more. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.30 μm.

[0351] Production Example 1-26; Preparation of Core-Shell Polymer Latex (L-26) In Production Example 1-25, a latex (L-30) of a core-shell polymer was obtained in the same manner as in Production Example 1-25, except that <33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> was used instead of <38 parts by weight of MMA, 38 parts by weight of BA, 0.46 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.32 μm.

[0352] Production Example 1-27; Preparation of Core-Shell Polymer Latex (L-27) Into a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and a device for adding monomers and emulsifiers, 182 parts by weight of deionized water, 0.006 parts by weight of EDTA, 0.0015 parts by weight of FE, 1.5 parts by weight of SFS, and 0.01 parts by weight of SDS were charged, and the temperature was raised to 60 °C while stirring in a nitrogen stream. Next, a mixture of core layer monomers (12 parts by weight of MMA, 12 parts by weight of BA, 1.2 parts by weight of ALMA) and 0.04 parts by weight of CHP was added dropwise over 1 hour. Also, while adding the above monomer mixture, 20 parts by weight of a 5 wt% aqueous solution of SDS was continuously added over 1 hour. Stirring was continued for 1 hour after the addition of the monomer mixture was completed to complete the polymerization, and a latex containing acrylic polymer particles was obtained. Subsequently, 2 parts by weight of triallyl isocyanurate (TAIC) as the intermediate layer monomer and 0.03 parts by weight of CHP were added thereto, and stirring was continued for 1 hour to effect polymerization. Subsequently, a mixture of graft monomers (33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA) and 0.46 parts by weight of CHP was continuously added over 3 hours. After the addition was completed, 0.07 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, obtaining a latex (L-27) containing a core-shell polymer. The polymerization conversion rate of the monomer component was 99% or more. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0353] Production Example 1-28; Preparation of Core-Shell Polymer Latex (L-28) In Production Example 1-27, a latex (L-28) of a core-shell polymer was obtained in the same manner as in Production Example 1-27, except that <12 parts by weight of MMA, 24 parts by weight of BA, 30 parts by weight of BMA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> was used instead of <33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0354] Production Example 1-29; Preparation of Core-Shell Polymer Latex (L-29) In Production Example 1-27, a latex (L-29) of a core-shell polymer was obtained in the same manner as in Production Example 1-27, except that <12 parts by weight of MMA, 24 parts by weight of BA, 30 parts by weight of BMA, 10 parts by weight of GMA, 1.37 parts by weight of CHP> was used instead of <33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0355] Production Example 1-30; Preparation of Core-Shell Polymer Latex (L-30) In Production Example 1-27, a latex (L-30) of a core-shell polymer was obtained in the same manner as in Production Example 1-27, except that <22 parts by weight of MMA, 24 parts by weight of BA, 30 parts by weight of BMA, 1.37 parts by weight of CHP> was used instead of <33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0356] Production Example 1-31; Preparation of Core-Shell Polymer Latex (L-31) In Production Example 1-27, a latex (L-31) of a core-shell polymer was obtained in the same manner as in Production Example 1-27, except that <20 parts by weight of MMA, 24 parts by weight of BA, 30 parts by weight of BMA, 2 parts by weight of acrylonitrile (AN), 1.37 parts by weight of CHP> was used instead of <33 parts by weight of MMA, 33 parts by weight of BA, 10 parts by weight of GMA, 0.46 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.31 μm.

[0357] Production Example 1-32; Preparation of Core-Shell Polymer Latex (L-32) In Production Example 1-24, a latex (L-32) of a core-shell polymer was obtained in the same manner as in Production Example 1-24, except that <24 parts by weight of MMA, 24 parts by weight of BA, 4 parts by weight of GMA, 0.30 parts by weight of CHP> was used instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.94 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.36 μm.

[0358] Production Example 1-33; Preparation of Core-Shell Polymer Latex (L-33) In Production Example 1-24, a latex (L-33) of a core-shell polymer was obtained in the same manner as in Production Example 1-24, except that <26 parts by weight of MMA, 26 parts by weight of BA, 0.30 parts by weight of CHP> was used instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.94 parts by weight of CHP> as the graft monomer and its initiator (CHP). The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0359] Production Example 1-34; Preparation of Core-Shell Polymer Latex (L-34) In a pressure polymerization reactor, 200 parts by weight of water, 0.03 parts by weight of tripotassium phosphate, 0.002 parts by weight of EDTA, 0.001 parts by weight of FE, and 1.55 parts by weight of SDS were added. After thoroughly purging with nitrogen while stirring to remove oxygen, 100 parts by weight of butadiene (Bd) was added to the system and the temperature was raised to 45°C. 0.03 parts by weight of paramentane hydroperoxide (PHP) and then 0.10 parts by weight of SFS were added to start polymerization. 0.025 parts by weight of PHP were added at 3, 5, and 7 hours from the start of polymerization. Additionally, 0.0006 parts by weight of EDTA and 0.003 parts by weight of FE were added at 4, 6, and 8 hours from the start of polymerization. At 15 hours of polymerization, the remaining monomers were defoliated and removed under reduced pressure to terminate polymerization and obtain 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 0.08 μm.

[0360] In a pressure polymerization reactor, 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. After thoroughly purging with nitrogen while stirring to remove oxygen, 93 parts by weight of Bd was added to the system and the temperature was raised to 45°C. 0.02 parts by weight of PHP, followed by 0.10 parts by weight of SFS, were added to start polymerization. From the start of polymerization until 24 hours, 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, respectively. At 30 hours of polymerization, residual monomers were defoliated and removed under reduced pressure to terminate polymerization and obtain polybutadiene rubber latex (R-2) with polybutadiene rubber as the main component. The volume-average particle size of the polybutadiene rubber particles contained in the obtained latex was 0.20 μm.

[0361] In a glass reactor equipped with a thermometer, stirrer, reflux condenser, nitrogen inlet, and monomer addition device, 72 parts by weight of polybutadiene rubber latex (R-2) (containing 24 parts by weight of polybutadiene rubber particles) and 184 parts by weight of deionized water were charged and stirred at 60°C while purging with nitrogen. After adding 0.004 parts by weight of EDTA, 0.001 parts by weight of FE, and 0.8 parts by weight of SFS, a mixture of shell monomers (38 parts by weight of MMA, 38 parts by weight of BA) and 0.46 parts by weight of cumene hydroperoxide (CHP) was continuously added over 2 hours. In addition, along with the addition of the monomer mixture, 10 parts by weight of a 5% by weight aqueous solution of SDS was continuously added over 2 hours. After the addition was complete, 0.04 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, obtaining aqueous latex (L-34) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was 99% or higher. The volume-average particle size of the core-shell polymer particles contained in aqueous latex (L-34) was 0.27 μm.

[0362] Preparation Examples 1-35; Preparation of Core-Shell Polymer Latex (L-35) In a glass reactor equipped with a thermometer, stirrer, reflux condenser, nitrogen inlet, and monomer addition device, 256 parts by weight of polybutadiene rubber latex (R-2) obtained in Production Example 1-23 (containing 85 parts by weight of polybutadiene rubber particles) and 61 parts by weight of deionized water were charged and stirred at 60°C while purging with nitrogen. 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 (7 parts by weight of styrene (ST), 1.5 parts by weight of MMA, 2.5 parts by weight of AN, 4 parts by weight of GMA) and 0.04 parts by weight of cumene hydroperoxide (CHP) was continuously added over 2 hours. After the addition was complete, 0.04 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, yielding aqueous latex (L-35) containing core-shell polymer particles. The polymerization conversion rate of the monomer components was 99% or higher. The volume-average particle size of core-shell polymer particles contained in aqueous latex (L-35) was 0.21 μm.

[0363] Production Example 1-36; Preparation of Core-Shell Polymer Latex (L-36) In Production Example 1-23, instead of <8 parts by weight of MMA, 40 parts by weight of BA, 2.4 parts by weight of ALMA, 0.07 parts by weight of CHP> as the core layer monomer and its initiator (CHP), <12 parts by weight of MMA, 60 parts by weight of BA, 3.6 parts by weight of ALMA, 0.10 parts by weight of CHP> were used, and instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.23 parts by weight of CHP> as the graft monomer and its initiator (CHP), <4 parts by weight of MMA, 8 parts by weight of BA, 10 parts by weight of BMA, 4 parts by weight of GMA, 0.12 parts by weight of CHP> were used. Otherwise, in the same manner as in Production Example 1-23, a latex (L-36) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0364] Production Example 1-37; Preparation of Core-Shell Polymer Latex (L-37) In Production Example 1-23, instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.23 parts by weight of CHP> as the graft monomer and its initiator (CHP), <8 parts by weight of MMA, 36 parts by weight of BA, 8 parts by weight of GMA, 0.23 parts by weight of CHP> were used. Otherwise, in the same manner as in Production Example 1-23, a latex (L-37) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.33 μm.

[0365] Production Example 1-38; Preparation of Core-Shell Polymer Latex (L-38) In Production Example 1-24, instead of <8 parts by weight of MMA, 16 parts by weight of BA, 20 parts by weight of BMA, 8 parts by weight of GMA, 0.94 parts by weight of CHP> as the graft monomer and its initiator (CHP), <8 parts by weight of MMA, 40 parts by weight of BA, 4 parts by weight of GMA, 0.30 parts by weight of CHP> were used. Otherwise, in the same manner as in Production Example 1-24, a latex (L-38) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.35 μm.

[0366] Production Example 1-39; Preparation of Core-Shell Polymer Latex (L-39) In Production Example 1-1, except that <24 parts by weight of MMA, 40 parts by weight of BA, 23 parts by weight of ST, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer, a latex (L-39) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.16 μm.

[0367] Production Example 1-40; Preparation of Core-Shell Polymer Latex (L-40) In Production Example 1-1, except that <16 parts by weight of MMA, 40 parts by weight of BA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> was used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, and <2 parts by weight of MMA, 10 parts by weight of BA, 1 part by weight of GMA> was used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer, a latex (L-40) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.15 μm.

[0368] Production Example 1-41; Preparation of Core-Shell Polymer Latex (L-41) In Production Example 1-1, except that <16 parts by weight of MMA, 40 parts by weight of BA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> were used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers and <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, a latex (L-41) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.15 μm.

[0369] Production Example 1-42; Preparation of Core-Shell Polymer Latex (L-42) In Production Example 1-1, except that <8 parts by weight of MMA, 40 parts by weight of BA, 39 parts by weight of ST, 4.3 parts by weight of ALMA> were used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers and <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, a latex (L-42) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.15 μm.

[0370] Production Example 1-43; Preparation of Core-Shell Polymer Latex (L-43) In Production Example 1-1, except that <40 parts by weight of BA, 47 parts by weight of ST, 4.3 parts by weight of ALMA> were used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers and <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, a latex (L-43) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.14 μm.

[0371] Production Example 1-44; Preparation of Core-Shell Polymer Latex (L-44) In Production Example 1-1, except that <26 parts by weight of BMA, 30 parts by weight of BA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> were used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, and <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, a latex (L-44) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.14 μm.

[0372] Production Example 1-45; Preparation of Core-Shell Polymer Latex (L-45) In Production Example 1-1, except that <26 parts by weight of BMA, 4 parts by weight of BA, 26 parts by weight of MEA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> were used instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, and <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, a latex (L-45) of the core-shell polymer was obtained in the same manner as in Production Example 1-1. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.16 μm.

[0373] <00012�9>Production Example 1-46; Preparation of Core-Shell Polymer Latex (L-46) In Production Example 1-1, instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, <18 parts by weight of BMA, 12 parts by weight of BA, 18 parts by weight of 2-ethylhexyl acrylate (2EHA), 39 parts by weight of ST, 4.3 parts by weight of ALMA> were used, and instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used. Otherwise, in the same manner as in Production Example 1-1, a latex (L-46) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.13 μm.

[0374] Production Example 1-47; Preparation of Core-Shell Polymer Latex (L-47) In Production Example 1-1, instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomers, <26 parts by weight of BMA, 18 parts by weight of BA, 12 parts by weight of 4-hydroxybutyl acrylate (4HBA), 31 parts by weight of ST, 4.3 parts by weight of ALMA> were used, and instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomers, <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> were used. Otherwise, in the same manner as in Production Example 1-1, a latex (L-47) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.16 μm.

[0375] Production Example 1-48; Preparation of Core-Shell Polymer Latex (L-48) In Production Example 1-1, instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, <26 parts by weight of benzyl acrylate (BZA), 30 parts by weight of BA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> was used, and instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer, <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> was used. Otherwise, it was the same as in Production Example 1-1, and a latex (L-48) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.14 μm.

[0376] Production Example 1-49; Preparation of Core-Shell Polymer Latex (L-49) In Production Example 1-1, instead of <47 parts by weight of MMA, 40 parts by weight of BA, 0.43 parts by weight of ALMA> as the core layer monomer, <21 parts by weight of isobutyl methacrylate (IBMA), 35 parts by weight of BA, 31 parts by weight of ST, 4.3 parts by weight of ALMA> was used, and instead of <9.5 parts by weight of MMA, 1.2 parts by weight of BA, 1 part by weight of GMA, 1.3 parts by weight of ALMA> as the graft monomer, <7 parts by weight of MMA, 5 parts by weight of BA, 1 part by weight of GMA> was used. Otherwise, it was the same as in Production Example 1-1, and a latex (L-49) of the core-shell polymer was obtained. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.13 μm.

[0377] Production Example 1-50; Preparation of Latex (L-50) Containing Crosslinked Polymer Particles Having a Single-Layer Structure In a glass reactor equipped with a thermometer, stirrer, reflux condenser, nitrogen inlet, and monomer and emulsifier addition device, 182 parts by weight of deionized water, 0.006 parts by weight of EDTA, 0.0015 parts by weight of FE, 0.6 parts by weight of SFS, and 0.01 parts by weight of SDS were charged, and the mixture was heated to 60°C while stirring in a nitrogen atmosphere. Next, a mixture of core layer monomers (47 parts by weight of MMA, 40 parts by weight of BA, 4.3 parts by weight of ALMA) and 0.13 parts by weight of CHP was added dropwise over 3 hours. In addition, along with the addition of the monomer mixture, 20 parts by weight of a 5% by weight aqueous solution of SDS was continuously added over 3 hours. After the completion of the monomer mixture addition, stirring was continued for 1 hour to complete the polymerization, and a latex (L-50) containing cross-linked polymer particles with a single-layer structure was obtained. The polymerization conversion rate of the monomer components was 99% or more. The volume-average particle size of the cross-linked polymer particles with a single-layer structure contained in the obtained latex was 0.32 μm.

[0378] Preparation Examples 1-51; Preparation of Core-Shell Polymer Latex (L-51) Into a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and an addition device for monomers and emulsifiers, 215 parts by weight of deionized water, 0.0028 parts by weight of EDTA, 0.0007 parts by weight of FE, 0.1 parts by weight of SFS, and 0.6 parts by weight of SDS were charged, and the temperature was raised to 60 °C while stirring in a nitrogen stream. Next, a mixture of core layer monomers (33.5 parts by weight of BA, 41.5 parts by weight of ST, 3.8 parts by weight of ALMA), and 0.022 parts by weight of CHP was added dropwise over 3 hours. Also, together with the addition of the above monomer mixture, 20 parts by weight of a 5 wt% aqueous solution of SDS was continuously added over 3 hours. Stirring was continued for 1 hour after the addition of the monomer mixture was completed to complete the polymerization, and a latex containing acrylic polymer particles was obtained. Subsequently, 1.5 parts by weight of triallyl isocyanurate (TAIC) as an intermediate layer monomer and 0.03 parts by weight of CHP were added thereto, and stirring was continued for 1 hour to effect polymerization. Subsequently, a mixture of graft monomers (19.5 parts by weight of MMA, 0.5 parts by weight of BA, 5 parts by weight of GMA), and 0.34 parts by weight of CHP was continuously added over 150 minutes. After the addition was completed, 0.07 parts by weight of CHP was added, and stirring was continued for another 2 hours to complete the polymerization, obtaining a latex (L-51) containing a core-shell polymer. The polymerization conversion rate of the monomer components was 99% or more. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0379] Production Example 1-52; Preparation of Core-Shell Polymer Latex (L-52) In Production Example 1-51, a latex (L-52) of a core-shell polymer was obtained in the same manner as in Production Example 1-51, except that <19.5 parts by weight of methyl acrylate (MA), 0.5 parts by weight of BA, 5 parts by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, 5 parts by weight of GMA> as the graft monomer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0380] Production Example 1-53; Preparation of Core-Shell Polymer Latex (L-53) In Production Example 1-51, a core-shell polymer latex (L-53) was obtained in the same manner as in Production Example 1-51, except that <23.5 parts by weight of MA, 0.5 parts by weight of BA, and 1 part by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, and 5 parts by weight of GMA> as the graft monomer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0381] Production Example 1-54; Preparation of Core-Shell Polymer Latex (L-54) In Production Example 1-51, a core-shell polymer latex (L-54) was obtained in the same manner as in Production Example 1-51, except that <6 parts by weight of MMA, 12 parts by weight of MA, 6 parts by weight of BA, and 1 part by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, and 5 parts by weight of GMA> as the graft monomer. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0382] Production Example 1-55; Preparation of Core-Shell Polymer Latex (L-55) In Production Example 1-51, <22 parts by weight of BMA, 26 parts by weight of BA, 27 parts by weight of ST, and 3.8 parts by weight of ALMA> was used instead of <33.5 parts by weight of BA, 41.5 parts by weight of ST, and 3.8 parts by weight of ALMA> as the core layer monomer, and <12.5 parts by weight of MMA, 11.5 parts by weight of BA, and 1 part by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, and 5 parts by weight of GMA> as the graft monomer. A core-shell polymer latex (L-55) was obtained in the same manner as in Production Example 1-51. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0383] Production Example 1-56; Preparation of Core-Shell Polymer Latex (L-56) In Production Example 1-51, <26 parts by weight of BMA, 22 parts by weight of BA, 27 parts by weight of ST, 3.8 parts by weight of ALMA> was used instead of <33.5 parts by weight of BA, 41.5 parts by weight of ST, 3.8 parts by weight of ALMA> as the core layer monomer, and <23.5 parts by weight of MA, 0.5 parts by weight of BA, 1 part by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, 5 parts by weight of GMA> as the graft monomer. A latex (L-56) of the core-shell polymer was obtained in the same manner as in Production Example 1-51, except for the above changes. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0384] Production Example 1-57; Preparation of Core-Shell Polymer Latex (L-57) In Production Example 1-51, <26 parts by weight of BMA, 22 parts by weight of BA, 27 parts by weight of ST, 3.8 parts by weight of ALMA> was used instead of <33.5 parts by weight of BA, 41.5 parts by weight of ST, 3.8 parts by weight of ALMA> as the core layer monomer, and <20 parts by weight of MA, 4 parts by weight of ST, 1 part by weight of GMA> was used instead of <19.5 parts by weight of MMA, 0.5 parts by weight of BA, 5 parts by weight of GMA> as the graft monomer. A latex (L-57) of the core-shell polymer was obtained in the same manner as in Production Example 1-51, except for the above changes. The volume average particle diameter of the core-shell polymer contained in the obtained latex was 0.08 μm.

[0385] 2. Preparation of Dispersion (K) in Which Crosslinked Polymer Particles (B) are Dispersed in Curable Resin (Measurement of Viscosity of Dispersion (K)) The viscosity of the dispersion (K) in which polymer particles (B) are dispersed in curable resin was measured using a digital viscometer DV-II+Pro type manufactured by BROOKFIELD. Using spindle CPE-41 or CPE-52, at 50 °C, the viscosity at a Shear Rate (shear rate) of 10 (s -1 ) was measured.

[0386] Production Example 2-1; Preparation of Dispersion (K-1) 132 g of methyl ethyl ketone (MEK) was introduced into a 1 L mixing tank at 25°C, and while stirring, 132 g of core-shell polymer latex (L-1) obtained in Production Example 1-1 (equivalent to 40 g of core-shell polymer particles) was added. After uniform mixing, 200 g of water was added at a supply rate of 80 g / min. After the supply was completed, stirring was immediately stopped, and a slurry liquid consisting of floating aggregates and an aqueous phase containing some organic solvent was obtained. Next, leaving the aggregates containing some aqueous phase, 300 g of the aqueous phase was discharged from the outlet at the bottom of the tank. 500 g of MEK was added to the obtained aggregates and mixed uniformly to obtain a dispersion in which core-shell polymer particles were uniformly dispersed. To this dispersion, 120 g of epoxy resin (A-1; manufactured by Mitsubishi Chemical Corporation, JER828: liquid bisphenol A type epoxy resin, epoxy equivalent weight 184-194 g / eq, <epoxy resin corresponding to components (A1) and (A2)>) which is component (A), was mixed. MEK was removed from this mixture using a rotary evaporator. In this way, a dispersion (K-1) in which core-shell polymer particles were dispersed in epoxy resin was obtained. The viscosity of (K-1) was 16 Pa·s.

[0387] Manufacturing Example 2-2; Preparation of Dispersion (K-2) In Production Example 2-1, a dispersion (K-2) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-2) obtained in Production Example 1-2 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-2) was 29 Pa·s.

[0388] Manufacturing Example 2-3; Preparation of Dispersion (K-3) In Production Example 2-1, a dispersion (K-3) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-3) obtained in Production Example 1-3 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-3) was 29 Pa·s.

[0389] Manufacturing Example 2-4; Preparation of Dispersion (K-4) In Production Example 2-1, a dispersion (K-4) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-4) obtained in Production Example 1-4 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-4) was 45 Pa·s.

[0390] Preparation Example 2-5; Preparation of Dispersion (K-5) In Production Example 2-1, a dispersion (K-5) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-5) obtained in Production Example 1-5 was used as the core-shell polymer latex instead of (L-1), and 60 g of epoxy resin (A-1) was used instead of 120 g of epoxy resin (A-1). The viscosity of (K-5) was 12 Pa·s.

[0391] Preparation Example 2-6: Preparation of Dispersion (K-6) In Production Example 2-5, a dispersion (K-6) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-6) obtained in Production Example 1-6 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-6) was 11 Pa·s.

[0392] Manufacturing Example 2-7; Preparation of Dispersion (K-7) In Production Example 2-5, a dispersion (K-7) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-7) obtained in Production Example 1-7 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-7) was 27 Pa·s.

[0393] Manufacturing Example 2-8; Preparation of Dispersion (K-8) In Production Example 2-5, a dispersion (K-8) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-8) obtained in Production Example 1-8 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-8) was 19 Pa·s.

[0394] Manufacturing Example 2-9; Preparation of Dispersion (K-9) In Production Example 2-5, a dispersion (K-9) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-9) obtained in Production Example 1-9 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-9) was 25 Pa·s.

[0395] Preparation Example 2-10; Preparation of Dispersion (K-10) In Production Example 2-5, a dispersion (K-10) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-10) obtained in Production Example 1-10 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-10) was 73 Pa·s.

[0396] Preparation Example 2-11; Preparation of Dispersion (K-11) In Production Example 2-5, a dispersion (K-11) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-11) obtained in Production Example 1-11 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-11) was 45 Pa·s.

[0397] Preparation Example 2-12; Preparation of Dispersion (K-12) In Production Example 2-1, a dispersion (K-12) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-12) obtained in Production Example 1-12 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-12) was 150 Pa·s or higher.

[0398] Preparation Example 2-13: Preparation of Dispersion (K-13) In Production Example 2-1, a dispersion (K-13) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-13) obtained in Production Example 1-13 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-13) was 108 Pa·s.

[0399] Preparation Example 2-14; Preparation of Dispersion (K-14) In Production Example 2-1, a dispersion (K-14) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-14) obtained in Production Example 1-14 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-14) was 55 Pa·s.

[0400] Preparation Example 2-15; Preparation of Dispersion (K-15) In Production Example 2-1, a dispersion (K-15) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-15) obtained in Production Example 1-15 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-15) was 15 Pa·s.

[0401] Preparation Example 2-16: Preparation of Dispersion (K-16) In Production Example 2-1, a dispersion (K-16) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-16) obtained in Production Example 1-16 was used as the core-shell polymer latex instead of (L-1). The viscosity of (K-16) was 41 Pa·s.

[0402] Preparation Example 2-17; Preparation of Dispersion (K-17) In Production Example 2-1, a dispersion (K-17) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-17) obtained in Production Example 1-17 was used as the core-shell polymer latex instead of (L-1), and 60 g of epoxy resin (A-1) was used instead of 120 g of epoxy resin (A-1). The viscosity of (K-17) was 10 Pa·s.

[0403] Manufacturing Example 2-18; Preparation of Dispersion (K-18) In Production Example 2-1, a dispersion (K-18) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-2) obtained in Production Example 1-2 was used as the core-shell polymer latex instead of (L-1), and 60 g of epoxy resin (A-2; manufactured by Mitsubishi Chemical Corporation, JER871: dimer acid modified epoxy resin, epoxy equivalent of 410 g / eq, <epoxy resin that does not correspond to either component (A1) or (A2)>) was used instead of 120 g of epoxy resin (A-1). The viscosity of (K-18) was 19 Pa·s.

[0404] Preparation Example 2-19; ​​Preparation of Dispersion (K-19) In Production Example 2-18, a dispersion (K-19) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-3) obtained in Production Example 1-3 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-19) was 15 Pa·s.

[0405] Preparation Example 2-20; Preparation of Dispersion (K-20) In Production Example 2-18, a dispersion (K-20) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-18) obtained in Production Example 1-18 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-20) was 5 Pa·s.

[0406] Preparation Example 2-21; Preparation of Dispersion (K-21) In Production Example 2-18, a dispersion (K-21) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-19) obtained in Production Example 1-19 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-21) was 7 Pa·s.

[0407] Manufacturing Example 2-22; Preparation of Dispersion (K-22) In manufacturing example 2-18, core-shell polymer latex A dispersion (K-22) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-20) obtained in Production Example 1-20 was used instead of (L-2). The viscosity of (K-22) was 13 Pa·s.

[0408] Preparation Example 2-23; Preparation of Dispersion (K-23) In Production Example 2-18, a dispersion (K-23) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-21) obtained in Production Example 1-21 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-23) was 2 Pa·s.

[0409] Preparation Example 2-24; Preparation of Dispersion (K-24) In Production Example 2-18, a dispersion (K-24) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-22) obtained in Production Example 1-22 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-24) was 9 Pa·s.

[0410] Preparation Example 2-25; Preparation of Dispersion (K-25) In Production Example 2-18, a dispersion (K-25) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-5) obtained in Production Example 1-5 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-25) was 1 Pa·s.

[0411] Preparation Example 2-26; Preparation of Dispersion (K-26) In Production Example 2-18, a dispersion (K-26) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-5) obtained in Production Example 1-5 was used as the core-shell polymer latex instead of (L-2), and 26.7 g of epoxy resin (A-2) was used instead of 60 g of epoxy resin (A-2). The viscosity of (K-26) was 7 Pa·s.

[0412] Preparation Example 2-27; Preparation of Dispersion (K-27) In Production Example 2-18, a dispersion (K-27) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-19) obtained in Production Example 1-19 was used as the core-shell polymer latex instead of (L-2), and 80 g of epoxy resin (A-2) was used instead of 60 g of epoxy resin (A-2). The viscosity of (K-27) was 1 Pa·s.

[0413] Preparation Example 2-28; Preparation of Dispersion (K-28) In Production Example 2-17, a dispersion (K-28) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-17, except that (L-16) obtained in Production Example 1-16 was used as the core-shell polymer latex instead of (L-2). The viscosity of (K-28) was 5 Pa·s.

[0414] Preparation Example 2-29; Preparation of Dispersion (K-29) 132 g of methyl ethyl ketone (MEK) was introduced into a 1 L mixing tank at 25°C, and while stirring, 132 g of core-shell polymer latex (L-23) obtained in Production Example 1-23 (equivalent to 40 g of core-shell polymer particles) was added. After uniform mixing, 260 g of water was added at a supply rate of 80 g / min. After the supply was completed, stirring was stopped immediately, and a slurry liquid consisting of floating aggregates and an aqueous phase containing some organic solvent was obtained. Next, leaving the aggregates containing some aqueous phase, 440 g of the aqueous phase was discharged from the outlet at the bottom of the tank. 120 g of MEK was added to the obtained aggregates and mixed uniformly to obtain a dispersion in which core-shell polymer particles were uniformly dispersed. 80 g of epoxy resin (A-1), which is component (A), was mixed into this dispersion. MEK was removed from this mixture using a rotary evaporator. In this way, a dispersion (K-29) in which core-shell polymer particles were dispersed in epoxy resin was obtained. The viscosity of (K-29) was 45 Pa·s.

[0415] Preparation Example 2-30; Preparation of Dispersion (K-30) In Production Example 2-29, a dispersion (K-30) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-24) obtained in Production Example 1-24 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-30) was 14 Pa·s.

[0416] Preparation Example 2-31; Preparation of Dispersion (K-31) In Production Example 2-29, a dispersion (K-31) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-25) obtained in Production Example 1-25 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-31) was 150 Pa·s or higher.

[0417] Preparation Example 2-32; Preparation of Dispersion (K-32) In Production Example 2-29, a dispersion (K-32) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-26) obtained in Production Example 1-26 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-32) was 150 Pa·s or higher.

[0418] Preparation Example 2-33; Preparation of Dispersion (K-33) In Production Example 2-29, a dispersion (K-33) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-27) obtained in Production Example 1-27 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-33) was 140 Pa·s.

[0419] Preparation Example 2-34; Preparation of Dispersion (K-34) In Production Example 2-29, a dispersion (K-34) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-28) obtained in Production Example 1-28 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-34) was 49 Pa·s.

[0420] Preparation Example 2-35; Preparation of Dispersion (K-35) In Production Example 2-29, a dispersion (K-35) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-29) obtained in Production Example 1-29 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-35) was 16 Pa·s.

[0421] Preparation Example 2-36; Preparation of Dispersion (K-36) In Production Example 2-29, a dispersion (K-36) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-30) obtained in Production Example 1-30 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-36) was 11 Pa·s.

[0422] Preparation Example 2-37; Preparation of Dispersion (K-37) In Production Example 2-29, a dispersion (K-37) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-31) obtained in Production Example 1-31 was used as the core-shell polymer latex instead of (L-23). ​​The viscosity of (K-37) was 11 Pa·s.

[0423] Preparation Example 2-38; Preparation of Dispersion (K-38) In Production Example 2-29, a dispersion (K-38) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-29, except that (L-32) obtained in Production Example 1-32 was used as the core-shell polymer latex instead of (L-23), and 60 g of epoxy resin (A-1) was used instead of 80 g of epoxy resin (A-1). The viscosity of (K-38) was 111 Pa·s.

[0424] Preparation Example 2-39; Preparation of Dispersion (K-39) In Production Example 2-38, a dispersion (K-39) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-38, except that (L-33) obtained in Production Example 1-33 was used as the core-shell polymer latex instead of (L-32). The viscosity of (K-39) was 150 Pa·s or higher.

[0425] Preparation Example 2-40; Preparation of Dispersion (K-40) In Production Example 2-38, a dispersion (K-40) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-38, except that (L-34) obtained in Production Example 1-34 was used as the core-shell polymer latex instead of (L-32). The viscosity of (K-40) was 150 Pa·s or higher.

[0426] Preparation Example 2-41; Preparation of Dispersion (K-41) In Production Example 2-5, a dispersion (K-41) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-5, except that (L-35) obtained in Production Example 1-35 was used as the core-shell polymer latex instead of (L-5). The viscosity of (K-41) was 25 Pa·s.

[0427] Preparation Example 2-42; Preparation of Dispersion (K-42) In Production Example 2-38, a dispersion (K-42) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-38, except that (L-36) obtained in Production Example 1-36 was used as the core-shell polymer latex instead of (L-32). The viscosity of (K-42) was 24 Pa·s.

[0428] Preparation Example 2-43; Preparation of Dispersion (K-43) In Production Example 2-38, a dispersion (K-43) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-38, except that (L-37) obtained in Production Example 1-37 was used as the core-shell polymer latex instead of (L-32). The viscosity of (K-43) was 27 Pa·s.

[0429] Preparation Example 2-44; Preparation of Dispersion (K-44) In Production Example 2-38, a dispersion (K-44) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-38, except that (L-38) obtained in Production Example 1-38 was used as the core-shell polymer latex instead of (L-32). The viscosity of (K-44) was 150 Pa·s or higher.

[0430] Preparation Example 2-45; Preparation of Dispersion (K-45) In Production Example 2-18, a dispersion (K-45) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-18, except that (L-19) obtained in Production Example 1-19 was used as the core-shell polymer latex instead of (L-2), and 40 g of epoxy resin (A-2) was used instead of 60 g of epoxy resin (A-2). The viscosity of (K-45) was 27 Pa·s.

[0431] Preparation Example 2-46; Preparation of Dispersion (K-46) In Production Example 2-1, a dispersion (K-46) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-5) obtained in Production Example 1-5 was used as the core-shell polymer latex instead of (L-1).

[0432] Preparation Examples 2-47~57; Preparation of Dispersions (K-47~57) In Production Example 2-1, a dispersion (K-47 to K-57) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-39 to K-49) obtained in Production Examples 1-39 to K-49 was used as the core-shell polymer latex instead of (L-1).

[0433] Preparation Example 2-58; Preparation of Dispersion (K-58) In Production Example 2-1, a dispersion (K-58) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-50) obtained in Production Example 1-50 was used as the core-shell polymer latex instead of (L-1), and 60 g of epoxy resin (A-1) was used instead of 120 g of epoxy resin (A-1).

[0434] The viscosities of the dispersions (K-46~58) are shown in Table 5 below.

[0435] Preparation Examples 2-59~65; Preparation of Dispersions (K-59~65) In Production Example 2-1, a dispersion (K-59~65) in which core-shell polymer particles were dispersed in epoxy resin was obtained in the same manner as in Production Example 2-1, except that (L-51~57) obtained in Production Examples 1-51~57 was used as the core-shell polymer latex instead of (L-1), and 80g of epoxy resin (A-1) was used instead of 120g of epoxy resin (A-1).

[0436] The viscosities of the dispersions (K-59~65) are shown in Table 6 below.

[0437] (Examples 1-62, Comparative Examples 1-18) Each component was weighed according to the formulations shown in Tables 1 to 6 and thoroughly mixed to obtain a one-component curable resin composition.

[0438] For each of the one-component curable resin compositions listed in Tables 1 to 6, the elastic modulus and damping properties of the cured product were measured as follows.

[0439] <Dynamic Viscoelasticity Measurement> Each of the compositions in Tables 1 to 6 was defoamed, poured between two glass plates with a 3-mm-thick spacer sandwiched therebetween, and cured under the conditions of 170 °C for 60 minutes to obtain a cured plate with a thickness of 3 mm. This cured plate was cut into a strip shape of 30 mm × 5 mm × 3 mm, and using a dynamic viscoelasticity measuring device (DMA), the values of storage elastic modulus E’ and loss tangent (tanδ) were measured at a frequency of 20 Hz in a tensile mode within the temperature range of 0 to 150 °C. The storage elastic modulus E’ at 23 °C and 80 °C and the loss tangent (tanδ) at 40 °C are shown in Tables 1 to 6. The higher the elastic modulus, the higher the rigidity. Also, the smaller the decrease in the elastic modulus at 80 °C compared to that at 23 °C, the better the heat resistance. The larger the value of tanδ, the better the vibration damping property.

[0440] For each one-component curable resin composition in Tables 4 and 6, the adhesiveness was evaluated as follows.

[0441] <Shear adhesion strength> The curable resin composition was applied to two cold-rolled steel sheets (SPCC steel sheets) with dimensions of 25 × 100 × 1.6 mm, and bonded together so that the adhesive layer had a width of 25 mm × a length of 12.5 mm × a thickness of 0.13 mm, and cured under the conditions of 170 °C for 30 minutes to obtain a laminate.

[0442] Under the measurement conditions where the measurement temperature was 23 °C and the test speed was 1.3 mm / min, the shear adhesion strength in units of MPa was measured. The results are shown in Tables 4 and 6.

[0443] <T-peel adhesion strength> The curable resin composition was applied to two SPCC steel sheets with dimensions of 25 × 200 × 0.5 mm, overlapped so that the adhesive layer thickness was 0.25 mm, and cured under the conditions of 170 °C for 30 minutes, and the T-peel adhesion strength at 23 °C was measured in accordance with JIS K6854. The test results are shown in Tables 4 and 6.

[0444] <Dynamic tear resistance (impact-resistant peel adhesiveness)> A curable resin composition was applied to two SPCC steel plates, overlapped to create an adhesive layer thickness of 0.25 mm, and cured at 170°C for 30 minutes. The dynamic splitting resistance at 23°C was measured according to ISO 11343. The test results are shown in Tables 4 and 6.

[0445] The various compounding agents used in Tables 1 to 6 are as follows: <Epoxy resin (A)> A-1: JER828 (manufactured by Mitsubishi Chemical, liquid bisphenol A type epoxy resin at room temperature, epoxy equivalent: 184-194 g / eq, <epoxy resin corresponding to components (A1) and (A2)>) A-2: JER871 (manufactured by Mitsubishi Chemical Corporation, dimer acid modified epoxy resin, epoxy equivalent: 410 g / eq, <epoxy resin that does not correspond to either component (A1) or component (A2)>) A-3: Acrylonitrile butadiene copolymer-modified epoxy resin obtained by reacting HycarCTBN1300x8 (manufactured by CVC Thermoset Specialties, carboxyl-terminated acrylonitrile butadiene copolymer) and epoxy resin (A-1) in a 1:1 weight ratio at a temperature of 130°C. <Epoxy resin that does not correspond to either component (A1) or component (A2)> <Dispersion (K) in which cross-linked polymer particles (B) are dispersed in epoxy resin (A)> K-1~65: Dispersions obtained in the above manufacturing examples 2-1~65 <Blocked Urethane (C)> C-1: ADEKA Resin QR-9466 (made by ADEKA) <Epoxy hardener (D)> D-1: Dyhard 100S (AlzChem, dicyandiamide) <Curing accelerator (E)> E-1: Dyhard UR200 (manufactured by AlzChem, 3-(3,4-dichlorophenyl)-1,1-dimethylurea) E-2:2-Heptadecylimidazole (manufactured by Fujifilm Wako Pure Chemical Industries) ≪Fumed Silica≫ CAB-O-SIL TS-720 (Fumed silica manufactured by CABOT, surface-treated with polydimethylsiloxane), Carbon Black MONARCH 280 (made by Cabot) ≪Heavy Calcium Carbonate≫ Whiten SB (made from Shiraishi calcium, untreated heavy calcium carbonate, average particle size: 1.8 μm, specific surface area: 1.2 m²) 2 / g) ≪Wollastnight≫ NYAD 400 (manufactured by NYCO Minerals) Calcium Oxide CML#31 (Omi Chemical Industry Co., Ltd., calcium oxide surface-treated with fatty acids).

[0446] The Tg values ​​for the core layer and shell layer in Tables 1 to 15 were calculated using the Fox equation, based on the Tg values ​​of the homopolymers of the respective monomers used. Methyl methacrylate (MMA): 105°C, Butyl acrylate (BA): -54°C, Butyl methacrylate (BMA): 20°C Methoxyethyl acrylate (MEA): -50°C, Styrene (St): 100°C, Acrylonitrile (AN): 97°C Glycidyl methacrylate: 46°C, Allyl methacrylate (ALMA): 52°C, Butadiene (Bd): -85°C, 2-Ethylhexyl acrylate (2EHA): -70°C, 4-Hydroxybutyl acrylate (4HBA): -40°C, Benzyl acrylate (BZA): 6°C, Isobutyl methacrylate (IBMA): 48°C, Methyl acrylate (MA): 8°C [Table 1] [Table 2]

[0447] [Table 3] Tables 1-3 show that the curable resin compositions of Examples 1-13 of the present invention, which contain 0.1% to 10% by weight of a crosslinkable monomer and 60% or more by weight of a core layer (meth)acrylate polymer (M-1) with a Tg of -20°C to 30°C, have high tanδ values ​​and excellent damping properties, high elastic modulus at 80°C as well as high elastic modulus at 23°C, excellent heat resistance, and high rigidity at high temperatures.

[0448] On the other hand, the compositions of Comparative Example 1, which does not contain component (B-1); Comparative Example 2, which contains crosslinked polymer particles with a core layer Tg of less than -20°C; Comparative Examples 3 to 6, which contain crosslinked polymer particles with a core layer Tg greater than 30°C; and Comparative Example 7, which contains crosslinked polymer particles obtained by polymerizing a monomer mixture in which the core layer contains more than 10% by weight of crosslinkable monomers, have a small tanδ value and low attenuation. [Table 4] [Table 5]

[0449] [Table 6] Tables 4-6 show that the curable resin compositions of Examples 14, 15, 18-22, in which component (B-1) was added, and Examples 16, 17, 23, in which the crosslinked polymer particles (B-2) of the present invention, which contain a core layer <(meth)acrylate polymer (M-2)> with a Tg of -20°C to 30°C and do not contain a crosslinkable monomer, were added, exhibited high tanδ values ​​and excellent damping properties, high elastic modulus at 80°C as well as high elastic modulus at 23°C, excellent heat resistance, and high rigidity at high temperatures. In particular, the curable resin compositions with component (B-2) added showed higher tanδ values ​​with smaller additions than the curable resin compositions with component (B-1) added.

[0450] On the other hand, the compositions of Comparative Example 8, which does not contain component (B), and Comparative Example 9, which contains crosslinked polymer particles with a core layer Tg greater than 30°C, have a small tanδ value and low attenuation. [Table 7] [Table 8]

[0451] [Table 9] Tables 7-9 show that the curable resin compositions of Examples 24-35, to which the crosslinked polymer particles (B-3) of the present invention, which contain 30% to 90% by weight of a shell layer (meth)acrylate polymer (M-3) with a Tg of -20°C to 30°C, are added, have a high tanδ value and excellent damping properties, high elastic modulus not only at 23°C but also at 80°C, excellent heat resistance, and high rigidity at high temperatures.

[0452] On the other hand, the compositions of Comparative Example 10, which does not contain component (B-3); Comparative Example 11, which contains crosslinked polymer particles with a shell layer Tg greater than 30°C and a shell layer content of less than 30 wt%; Comparative Example 12, which contains crosslinked polymer particles with a shell layer content of less than 30 wt%; and Comparative Examples 13-14, which contain crosslinked polymer particles with a shell layer Tg less than -20°C, have small tanδ values ​​and low attenuation.

[0453] [Table 10] Table 10 shows that the curable resin compositions of Examples 36-38 of the present invention have high tanδ values ​​and excellent damping properties, high elastic modulus not only at 23°C but also at 80°C, excellent heat resistance, and high rigidity at high temperatures. Furthermore, they exhibit excellent adhesion with high shear bond strength and T-peel strength. In particular, Example 37, which further contains diene-based core-shell polymer particles as component (B-4), shows excellent impact-resistant peel adhesion.

[0454] On the other hand, Comparative Examples 15 and 16, which do not contain components (B-1 to B-3), have small tanδ values ​​and low damping properties. Furthermore, Comparative Examples 17 and 18, which were based on the examples in Japanese Patent Application Publication No. 2019-38926, have high tanδ values ​​and excellent damping properties, but their elastic modulus at 80°C is very low, and their rigidity at high temperatures is a problem. [Table 11] [Table 12]

[0455] [Table 13] Tables 11-13 show that the curable resin compositions of Examples 39-50, which contain 0.1% to 10% by weight of a crosslinkable monomer and 60% or more by weight of a core layer (meth)acrylate polymer (M-1) with a Tg of -20°C to 30°C, have high tanδ values ​​and excellent damping properties, high elastic modulus at 80°C as well as high elastic modulus at 23°C, excellent heat resistance, and high rigidity at high temperatures.

[0456] In particular, the curable resin compositions of Examples 40 to 50, in which the core layer is a polymer of styrene monomers (10% to 70% by weight), have a higher tanδ value than the curable resin composition of Example 39, which has a core layer that does not contain styrene monomers.

[0457] Furthermore, the curable resin composition of Example 42, in which the shell layer Tg is between -20°C and 30°C, has a higher tanδ value than the curable resin composition of Example 41, in which the shell layer Tg is less than -20°C.

[0458] Furthermore, the curable resin compositions of Examples 45, 47, and 50, in which the core layer is a polymer of monomer mixture containing a large amount (50% to 90% by weight) of unsubstituted alkyl (meth)acrylates having 3 to 20 carbon atoms, have a higher tanδ value than the curable resin compositions containing less than 50% by weight.

[0459] On the other hand, the curable resin composition of Example 51, to which the crosslinked polymer particles (B-1) of the present invention are added, contains 0.1% to 10% by weight of a crosslinkable monomer and has a single layer of (meth)acrylate polymer (M-1) with a Tg of -20°C to 30°C, also has a high tanδ value and excellent damping properties, and it can be seen that it has excellent heat resistance with a high modulus of elasticity not only at 23°C but also at 80°C, as well as high rigidity at high temperatures. [Table 14]

[0460] [Table 15] Tables 14 and 15 show that the curable resin compositions of Examples 52 to 62, which contain 0.1% to 10% by weight of a crosslinkable monomer and 60% or more by weight of a core layer (meth)acrylate polymer (M-1) with a Tg of -20°C to 30°C, have high tanδ values ​​and excellent damping properties, high elastic modulus at 80°C as well as high elastic modulus at 23°C, excellent heat resistance, and high rigidity at high temperatures.

[0461] In particular, the curable resin compositions of Examples 53 to 62, in which the core layer is a polymer of styrene monomers (10% to 70% by weight), have high tanδ values.

[0462] Furthermore, the curable resin composition of Example 54, in which the shell layer Tg is between -20°C and 30°C, has a higher tanδ value than the curable resin composition of Example 53, in which the shell layer Tg is greater than 30°C.

[0463] On the other hand, the curable resin compositions of Examples 53-57 and 59-62, in which the shell layer is a polymer of monomer mixture containing a large amount (70% to 100% by weight) of alkyl (meth)acrylates having 1 to 2 carbon atoms, exhibit high T-peel adhesion strength.

[0464] Furthermore, the curable resin compositions of Examples 60 and 61, which contain blocked urethane (C), have a higher tanδ value than the curable resin composition of Example 59, which does not contain blocked urethane (C).

Claims

1. A curable resin composition containing 100 parts by weight of epoxy resin (A) and 1 to 100 parts by weight of crosslinked polymer particles (B), A curable resin composition in which the crosslinked polymer particles (B) include one or more crosslinked polymer particles selected from the group consisting of crosslinked polymer particles (B-1), crosslinked polymer particles (B-2), and crosslinked polymer particles (B-3) as described in (1) to (3) below; (1) The crosslinked polymer particles (B-1) have a core-shell structure or a monolayer structure including a core layer and a shell layer, and the core layer and / or the monolayer contains a (meth)acrylate polymer (M-1) obtained by polymerizing a monomer mixture (m-1) containing 0.1% to 10% by weight of a crosslinkable monomer, having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the (meth)acrylate polymer (M-1) is contained in an amount of 60% by weight or more of the total amount of (B-1), and the shell layer contains a (meth)acrylate polymer (M-1') obtained by graft polymerizing the monomer mixture (m-1') onto the core layer, (2) The crosslinked polymer particles (B-2) have a core-shell structure comprising a core layer and a shell layer, wherein the core layer comprises a (meth)acrylate polymer (M-2) obtained by polymerizing a monomer mixture (m-2) that does not contain a crosslinkable monomer, and having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the shell layer comprises a (meth)acrylate polymer (M-2') obtained by graft polymerization of a monomer mixture (m-2') containing 1% to 100% by weight of the crosslinkable monomer onto the core layer, and the content of the (meth)acrylate polymer (M-2) is 60% to 95% by weight of the total amount of the crosslinked polymer particles (B-2) (3) The crosslinked polymer particles (B-3) have a core-shell structure including a core layer and a shell layer, the shell layer contains a (meth)acrylate polymer (M-3') having a glass transition temperature of -20°C to 30°C as determined by the Fox formula, and the content of the shell layer relative to the total amount of the crosslinked polymer particles (B-3) is 30% to 90% by weight. The crosslinked polymer particles (B-3) have one or more core layers selected from the group consisting of diene polymers, (meth)acrylate polymers (M-3), and organosiloxane polymers. The core layer of the crosslinked polymer particles (B-3) contains a (meth)acrylate polymer (M-3-a) obtained by polymerizing a monomer mixture (m-3-a) containing 0.1% to 10% by weight of a crosslinkable monomer. Of the total amount of the crosslinked polymer particles (B-3) (100% by weight), the content of the (meth)acrylate polymer (M-3') is 51% by weight or more and 90% by weight or less. In all of the crosslinked polymer particles (B-1), (B-2), and (B-3), the crosslinkable monomer is one or more selected from the group consisting of allyl (meth)acrylate, allylalkyl (meth)acrylate, allyloxyalkyl (meth)acrylate, (poly)ethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene.

2. The curable resin composition according to claim 1, wherein the storage modulus of a cured product obtained by curing the curable resin composition is 50 MPa or more at 23°C, and the storage modulus is a value obtained by measuring at a frequency of 20 Hz by dynamic viscoelasticity measurement.

3. The curable resin composition according to claim 1 or 2, wherein the epoxy resin (A) contains epoxy resin (A1) having an epoxy equivalent of 90 g / eq or more and less than 200 g / eq, and the content of epoxy resin (A1) in the total amount of epoxy resin (A) is 25% by weight or more.

4. The curable resin composition according to any one of claims 1 to 3, wherein the epoxy resin (A) contains a bisphenol A type epoxy resin (A2) and / or a bisphenol F type epoxy resin (A2), and the content of the bisphenol A type epoxy resin (A2) and the bisphenol F type epoxy resin (A2) in the total amount of the epoxy resin (A) is 25% by weight or more.

5. The curable resin composition according to any one of claims 1 to 4, wherein the crosslinked polymer particles (B-1) are single-layer crosslinked polymer particles composed solely of the (meth)acrylate polymer (M-1).

6. The curable resin composition according to any one of claims 1 to 5, wherein the content of the crosslinked polymer particles (B-2) in the core layer is 50 parts by weight or more and 95 parts by weight or less relative to the total amount of the crosslinked polymer particles (B-2).

7. The curable resin composition according to any one of claims 1 to 6, wherein the (meth)acrylate polymer (M-3') in the crosslinked polymer particles (B-3) includes a polymer obtained by polymerizing a monomer mixture (m-3') having a crosslinkable monomer content of 0.0% by weight or more and 2.0% by weight or less.

8. The curable resin composition according to claim 7, wherein the (meth)acrylate polymer (M-3') includes a polymer obtained by polymerizing a monomer mixture (m-3'-a) that does not contain a crosslinkable monomer.

9. The curable resin composition according to any one of claims 1 to 8, wherein the content of epoxy groups in the (meth)acrylate polymer (M-3') is 0.0 mmol / g or more and 2.0 mmol / g or less relative to the total amount of (M-3').

10. The curable resin composition according to claim 9, wherein the (meth)acrylate polymer (M-3') does not contain an epoxy group.

11. The curable resin composition according to any one of claims 1 to 10, wherein the (meth)acrylate polymer (M-3-a) comprises a (meth)acrylate polymer (M-3-b) having a glass transition temperature of -20°C or higher and 30°C or lower as determined by the Fox formula.

12. The curable resin composition according to any one of claims 1 to 4 and 6, wherein the (meth)acrylate polymer (M-1' and / or M-2') is a (meth)acrylate polymer (M-1'-a and / or M-2'-a) having a glass transition temperature of -20°C or higher and 30°C or lower as determined by the Fox formula.

13. The curable resin composition according to any one of claims 1 to 12, wherein the (meth)acrylate polymer (M-1 to M-3) is a (meth)acrylate polymer (M-1 to M-3) obtained by polymerizing a monomer mixture (m-1 to M-3) having a styrene monomer content of 10% by weight or more and 70% by weight or less.

14. The curable resin composition according to any one of claims 1 to 13, wherein the (meth)acrylate polymer (M-1 to M-3) is a monomer mixture (m-1 to M-3) having a content of 50% to 90% by weight of unsubstituted alkyl (meth)acrylate having 3 to 20 carbon atoms.

15. The curable resin composition according to any one of claims 1 to 14, wherein the (meth)acrylate polymer (M-1' to 3') is a (meth)acrylate polymer (M-1' to 3') obtained by polymerizing a monomer mixture (m-1' to 3') having a carbon-1 or carbon-2 alkyl (meth)acrylate content of 70% by weight or more and 100% by weight or less.

16. The curable resin composition according to any one of claims 1 to 15, further comprising 1 to 50 parts by mass of blocked urethane (C) per 100 parts by mass of epoxy resin (A).

17. The curable resin composition according to any one of claims 1 to 16, further comprising 1 to 80 parts by mass of epoxy curing agent (D) per 100 parts by mass of epoxy resin (A).

18. The curable resin composition according to any one of claims 1 to 17, further comprising 0.1 to 10.0 parts by mass of a curing accelerator (E) per 100 parts by mass of the epoxy resin (A).

19. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 18.

20. An adhesive comprising the curable resin composition according to any one of claims 1 to 18.

21. A structural adhesive for weld bonds comprising the curable resin composition according to any one of claims 1 to 18.

22. A laminate comprising two substrates and an adhesive layer formed by curing the adhesive according to claim 20 or the structural adhesive for weld bonding according to claim 21, which joins the two substrates.

23. A vehicle member having a closed cross-section structure, wherein two or more base materials, each having a closed cross-section and a joining flange at its end, are joined together, and the adhesive described in claim 20 or the structural adhesive for weld bonds described in claim 21 is applied between the joining flanges of the two base materials, and the adhesive is then cured to join them.

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