Cured resin composition and use thereof

Abstract

To provide a curable resin composition capable of providing a cured product having excellent toughness. A curable resin composition comprising: a specific amount of (A) component, which is a specific epoxy group-containing substance; a specific amount of (B) component, which is a polymer particle having a specific structure; and a specific amount of (C) component, which is a specific epoxy curing agent, the curable resin composition not containing or containing a specific amount of a curing accelerator as (D) component, the curable resin composition having a value X or Y within a specific range.

Description

Technical Field

[0001] This invention relates to curable resin compositions and their uses. Background Technology

[0002] Regarding curable resin compositions containing epoxy resin, for example, as described in Patent Documents 1-7, they are used in the field of fiber-reinforced composite materials and fiber-reinforced molded articles.

[0003] [Existing Technical Documents]

[0004] (Patent Documents)

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-35210

[0006] Patent Document 2: Japanese Patent Publication No. 2023-502717

[0007] Patent Document 3: Japanese Patent Application Publication No. 2023-139383

[0008] Patent Document 4: Japanese Patent Application Publication No. 2021-116404

[0009] Patent Document 5: Japanese Patent Application Publication No. 2023-146870

[0010] Patent Document 6: International Publication WO2023 / 089997

[0011] Patent Document 7: Japanese Patent Application Publication No. 8-183836 Summary of the Invention

[0012] (The problem that the invention aims to solve)

[0013] However, from the perspective of the toughness of the solidified material, the existing technology described above is not sufficient and there is room for further improvement.

[0014] One embodiment of the present invention was made in view of the above-mentioned problems, and the object is to provide a novel curable resin composition that can provide a cured product with excellent toughness.

[0015] (Technical means used to solve the problem)

[0016] The inventors conducted in-depth research to solve the above-mentioned problems, and as a result, completed this invention.

[0017] That is, the curable resin composition of one embodiment of the present invention comprises components (A) and (B) below, and does not contain component (D) below, or further comprises component (D) below.

[0018] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0019] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0020] (D) Ingredient: Curing accelerator,

[0021] Furthermore, the curable resin composition satisfies at least one of the following conditions (1) to (3): (1)

[0023] It also contains the following components (C): acid anhydride (C1), aromatic amine (C2) or alicyclic amine (C3).

[0024] Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight.

[0025] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0026] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0027] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0028] The value X of the curable resin composition is calculated by the following formula.

[0029] When component (C) is the acid anhydride (Cl), the concentration is 1.05–5.50.

[0030] When component (C) is the aromatic amine (C2) or the alicyclic amine (C3), the content is 1.30 to 9.00.

[0031] Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]; (2)

[0033] It also contains the following component (C): Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0034] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0035] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0036] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0037] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0038] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0039] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0040] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0041] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0042] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0043] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; (3)

[0045] It also contains the following component (C): amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is 1 or 2.

[0046] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0047] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0048] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0049] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0050] The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C).

[0051] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0052] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)];

[0053] in,

[0054] In the formulas for calculating the value X and the value Y,

[0055] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum value of the storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained. Furthermore, the composition (M) contains components related to the cured product... The resin composition contains the same components (A), (C), and (D) as components (D), and the composition (M) contains the same amounts of components (A), (C), and (D) as those in the curable resin composition. The cured product (M) is obtained by curing the composition (M) and exhibits a degree of cure of 98% or higher as measured by DSC.

[0056] In the formula for calculating the value X,

[0057] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as the sample and under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature at which E'(Meq) is obtained. The temperature (°C) at which the value is determined, and the composition (Meq) contains the same components (A), (C), and (D) as those contained in the curing resin composition, wherein the content of each of components (A) and (D) in the composition (Meq) is the same as the content of each of components (A) and (D) in the curing resin composition, and the component (C) in the composition (Meq) is... When the acid anhydride (c1) is present, the content of component (C) in the composition (Meq) is such that the molar amount of the acid anhydride group in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq), i.e., the ratio of the molar amount of the acid anhydride group in component (C) / the molar amount of the epoxy group in component (A) is 1. When component (C) in the composition (Meq) is the aromatic amine (c2) or the alicyclic amine (c3), the content of component (C) in the composition (Meq) is such that the content of component (C ... The content of component (C) in the composition (Meq) is such that the molar amount of active hydrogen of the amine in component (C) is relative to the molar amount of epoxy group in component (A) contained in the composition (Meq), that is, the ratio of the molar amount of active hydrogen of the amine in component (C) / the molar amount of epoxy group in component (A) is 1. The cured product (Meq) is a cured product obtained by curing the composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0058] (Invention effect)

[0059] According to one embodiment of the present invention, a novel curable resin composition is provided that can provide a cured product with excellent toughness. Detailed Implementation

[0060] The following describes one embodiment of the present invention, but the present invention is not limited thereto. The present invention is not limited to the embodiments described below, and various modifications can be made within the scope of the technical concept described in its entirety. Furthermore, embodiments or examples obtained by combining the technical means disclosed in different embodiments or examples are also included within the technical scope of the present invention. Moreover, new technical features can be formed by combining the technical means disclosed in each embodiment. Here, all academic and patent documents recorded in this specification are cited as references. In addition, in this specification, unless otherwise specified, "A~B" expressing a numerical range means "A or more (including A and greater than A) and B or less (including B and less than B)".

[0061] In this specification, the term "curable resin composition" is sometimes referred to as "composition" and "curable resin composition of an embodiment of the present invention" is sometimes referred to as "this composition".

[0062] In this specification, the term "X unit" in a polymer, copolymer, or resin refers to a "structural unit derived from monomer X". For example, "butadiene unit" refers to a "structural unit derived from butadiene monomer".

[0063] [1. Curable resin composition]

[0064] The curable resin composition of one embodiment of the present invention comprises components (A) and (B) below, and does not contain component (D) below or further comprises component (D) below.

[0065] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0066] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0067] (D) Ingredient: Curing accelerator,

[0068] Furthermore, the curable resin composition of one embodiment of the present invention satisfies at least one of the following items (1) to (3). (1)

[0070] It also contains the following components (C): acid anhydride (C1), aromatic amine (C2) or alicyclic amine (C3).

[0071] Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight.

[0072] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0073] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0074] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0075] The value X of the curable resin composition is calculated by the following formula.

[0076] When component (C) is the acid anhydride (Cl), the concentration is 1.05–5.50.

[0077] When component (C) is the aromatic amine (C2) or the alicyclic amine (C3), the content is 1.30 to 9.00.

[0078] Calculation formula: X={[273+Tmin(M)] / [273+Tmin(Meq)]}×[E'(Meq)] / [E'(M)]. (2)

[0080] It also contains the following component (C): Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0081] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0082] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0083] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0084] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0085] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0086] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0087] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0088] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0089] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0090] Calculation formula: Y=[273+Tmin(M)] / [E'(M)]. (3)

[0092] It also contains the following component (C): amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is 1 or 2.

[0093] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0094] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0095] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0096] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0097] The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C).

[0098] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0099] Calculation formula: Y=[273+Tmin(M)] / [E'(M)].

[0100] The cured product formed by curing the composition (M) is referred to as "cured product (M)". Cured product (M) can also be described as "cured product (M) of composition (M)". The cured product (M) is used as a sample, and dynamic viscoelasticity is measured under tensile mode and a frequency of 1 Hz. The loss tangent and storage modulus are determined through this dynamic viscoelasticity measurement. The temperature at which the loss tangent of the cured product (M) is maximized is defined as Ttg(M) (°C). In the above calculation formula, E'(M) represents the minimum value of the storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)], and Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0101] Composition (M) contains the same components (A), (C), and (D) as those contained in this composition. The amounts of components (A), (C), and (D) in composition (M) are the same as those in this composition. Composition (M) does not contain component (B).

[0102] In other words, when calculating the value X of a curable resin composition containing components (A), (B), (C), and (D), the composition (M) used to calculate the value X is as follows: (i) it contains the same components (A), (C), and (D) as those contained in the curable resin composition; (ii) it does not contain component (B) as contained in the curable resin composition; and (iii) the amounts of components (A), (C), and (D) in the composition (M) are the same as the amounts of components (A), (C), and (D) in the curable resin composition. When calculating the value X of a curable resin composition that does not contain component (D), the composition (M) used to calculate the value X does not contain component (D).

[0103] Furthermore, when calculating the value Y of a certain curable resin composition containing components (A), (B), (C), and (D), the composition (M) used to calculate the value Y is as follows: (i) it contains the same components (A), (C), and (D) as those contained in the curable resin composition; (ii) it does not contain component (B) as contained in the curable resin composition; and (iii) the amounts of components (A), (C), and (D) in the composition (M) are the same as the amounts of components (A), (C), and (D) in the curable resin composition. When calculating the value Y of a curable resin composition that does not contain component (D), the composition (M) used to calculate the value Y does not contain component (D).

[0104] The cured product formed by curing the composition (Meq) is referred to as "cured product (Meq)". The cured product (Meq) can also be described as "cured product (Meq) of the composition (Meq)". The cured product (Meq) is used as a sample, and dynamic viscoelasticity is measured under tensile mode and a frequency of 1 Hz. The loss tangent and storage modulus are determined through this dynamic viscoelasticity measurement. The temperature at which the loss tangent of the cured product (Meq) is maximized is defined as Ttg(Meq) (°C). In the above calculation formula, E'(Meq) represents the minimum value of the storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)], and Tmin(Meq) (°C) is the temperature (°C) at which the value of E'(Meq) is obtained.

[0105] The composition (Meq) contains the same components (A), (C), and (D) as those contained in the composition. The composition (Meq) does not contain component (B). The amounts of components (A) and (D) in the composition (Meq) are the same as those of components (A) and (D) in the composition. When component (C) in the composition (Meq) is an anhydride (Cl), the amount of component (C) in the composition (Meq) is such that the ratio of the molar amount of the anhydride group in component (C) to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of anhydride group in component (C) / molar amount of the epoxy group in component (A)) is 1. When component (C) in composition (Meq) is an aromatic amine (C2) or an alicyclic amine (C3), the content of component (C) in composition (Meq) is such that the ratio of the molar amount of active hydrogen in the amine of component (C) to the molar amount of epoxy groups in component (A) contained in composition (Meq) (molar amount of active hydrogen in amine of component (C) / molar amount of epoxy groups in component (A)) is 1. The content of component (D) in composition (Meq) is the same as the content of component (D) in this composition. In other words, when calculating the value X of a curable resin composition containing components (A), (B), (C), and (D), the composition (Meq) used to calculate the value X is as follows: (i) it contains the same components (A), (C), and (D) as those contained in the curable resin composition; (ii) it does not contain component (B) as contained in the curable resin composition; and (iii) the amounts of components (A) and (D) in the composition (Meq) are the same as the amounts of components (A) and (D) in the curable resin composition. When calculating the value X of a curable resin composition that does not contain component (D), the composition (Meq) used to calculate the value X does not contain component (D).

[0106] This composition possesses the above-described properties, and therefore has the advantage of providing a cured product with excellent toughness. In this specification, the toughness of the cured product is measured by the breaking toughness value "K1c (MPa·m)". 1 / 2 ")" and "G1c(Kj / m 2 The evaluation is based on the "destructive toughness" value. The higher the destructive toughness value of the solidified material, the better its toughness.

[0107] It should be noted that, in this specification, "cured product" refers to a cured product composed of a curable resin composition, with a degree of curing of 98% or higher as measured by DSC. The same concept of curing applies to the cured product (M) and cured product (Meq) used in calculating values ​​X and Y. For the measured breaking toughness value, i.e., "K1c (MPa·m... 1 / 2")" and "G1c(Kj / m 2 The concept of curing is the same for cured products. For example, "cured product (M)" refers to a cured product obtained by curing a composition (M) and exhibiting a degree of curing of 98% or more as measured by DSC. Similarly, "cured product (Meq)" refers to a cured product obtained by curing a composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0108] Values ​​X and Y may be affected by the degree of curing of the cured product (M) and cured product (Meq) as measured by DSC. In this specification, values ​​X and Y are calculated using cured products (M) and cured products (Meq) with a degree of curing of 98% or higher as measured by DSC. The degree of curing of the cured product as measured by DSC may be affected by the curing temperature and curing time of the composition (M).

[0109] In the calculation of values ​​X and Y, by curing composition (M) and composition (Meq) under the following curing conditions, cured products (M) and cured products (Meq) with a degree of curing of 98% or more as determined by DSC can be obtained.

[0110] Curing conditions: When component (C) is the acid anhydride (Cl), for example, the curing temperature is 175°C and the curing time is 2 hours;

[0111] When component (C) is the aromatic amine (C2), the curing temperature is 175°C and the curing time is 2 hours;

[0112] When component (C) is the alicyclic amine (C3), the curing temperature is 120°C and the curing time is 2 hours;

[0113] When component (C) is an amine (C4) with an average of 1 or 2 active hydrogens on the amino group per molecule, for example, the curing temperature is 120°C and the curing time is 2 hours.

[0114] The degree of curing of the cured product is a curing reaction rate calculated based on the total calorific value of the uncured curable resin composition as measured by DSC (differential scanning calorimeter) and the residual calorific value of the cured product formed by curing the resin composition. Specific methods for determining the degree of curing of the cured product will be described in detail in the following examples.

[0115] [1-1. A curable resin composition that at least satisfies the aforementioned condition (1)]

[0116] The following section describes a curable resin composition that at least satisfies the aforementioned condition (1).

[0117] <1-1-1. Technical concept of a curable resin composition that at least satisfies the aforementioned matter (1)>

[0118] In terms of toughness, there is still room for improvement in previously known curable resin compositions. Therefore, the inventors have conducted in-depth research with the aim of providing novel curable resin compositions that offer excellent toughness.

[0119] In curable resin compositions containing epoxy-containing substances (such as epoxy resins), the crosslinking density of the cured product is highest when the molar amount of the curing agent is equal to the molar amount of epoxy groups in the epoxy-containing substance. For example, in a curable resin composition containing an epoxy-containing substance and an acid anhydride as a curing agent, the crosslinking density of the cured product is highest when the molar ratio of the anhydride group in the anhydride to the molar ratio of the epoxy group in the epoxy-containing substance is 1. Similarly, in a curable resin composition containing an epoxy-containing substance and an aromatic amine or alicyclic amine as a curing agent, the crosslinking density of the cured product is highest when the molar ratio of the active hydrogen of the amine in the aromatic amine or alicyclic amine to the molar ratio of the epoxy group in the epoxy-containing substance is 1. The higher the crosslinking density of the cured product, the smaller the molecular weight between crosslinking points. Therefore, it can be said that if the crosslinking density of the cured product is the highest, the molecular weight between crosslinking points is the lowest.

[0120] Through in-depth research, the inventors have independently obtained the following new insights: by controlling the molecular weight between the crosslinking points of the cured material within a specific range and using polymer particles, the toughness of the cured material is surprisingly excellent.

[0121] Here, for example, we will explain how to "control the molecular weight between crosslinking points of the cured product within a specific range" using a curable resin composition (α) containing an epoxy-containing substance (component (A)), polymer particles (component (B)), a curing agent (component (C)), and a curing accelerator (component (D)). First, we prepare a composition (α) containing the same components (A), (C), and (D) as the curable resin composition (α), and in the same amounts as the curable resin composition (α) (i.e., a composition without component (B)). Next, we prepare a composition (αeq) containing the same components (A), (C), and (D) as the curable resin composition (α) (i.e., a composition without component (B)). In composition (αeq), the amounts of components (A) and (D) are the same as the amounts of the same components in the curable resin composition (α). In the composition (αeq), the amount of component (C) is such that the molar amount of the functional group in component (C) that reacts with the epoxy group (e.g., if component (C) is an anhydride, then the anhydride group; if component (C) is an aromatic amine or an alicyclic amine, then the active hydrogen group of the amine) is equal to the molar amount of the epoxy group in component (A). The ratio of the molecular weight between the crosslinking points of the cured product (α) formed by curing the composition (α) to the molecular weight between the crosslinking points of the cured product (αeq) formed by curing the composition (α) (molecular weight between the crosslinking points of the cured product (α) / molecular weight between the crosslinking points of the cured product (αeq)) is controlled within a specific range, which can be described as "controlling the molecular weight between the crosslinking points of the cured product within a specific range".

[0122] The molecular weight between the crosslinking points of the cured material can be calculated based on the theory of rubber elasticity of crosslinked rubber, according to, for example, the following formula:

[0123] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × T / E = ρ × R × T / G

[0124] In the formula, μ represents the Poisson's ratio of the cured product, ρ represents the specific gravity of the cured product, R represents the gas constant, T represents the absolute temperature (K), and E and G represent the Young's modulus and rigidity modulus of the cured product in the rubbery domain. The rubbery domain refers to the region further towards the higher temperature side of the transition region near the glass transition temperature obtained when measuring the temperature dependence of elastic modulus (Young's modulus, rigidity modulus, etc.), representing a region where the temperature dependence of elastic modulus is relatively flat. Crosslinked polymers such as epoxy resin cured products do not have a flow domain further towards the higher temperature side than the rubbery domain; therefore, E and G in the formula can be represented by the minimum values ​​of the Young's modulus and rigidity modulus of the rubbery domain. Furthermore, the Young's modulus of the rubbery domain is approximately equal to the storage modulus under the easily measured dynamic viscoelasticity, therefore the molecular weight between the crosslinking points can be calculated using the following formula.

[0125] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × (273 + Tmin) / E'min

[0126] In the formula, μ represents the Poisson's ratio of the cured material, ρ represents the specific gravity of the cured material, R represents the gas constant, E'min represents the minimum value of the storage elastic modulus of the cured material, and Tmin represents the temperature (°C) at which the storage elastic modulus of the cured material reaches its minimum value.

[0127] Therefore, the ratio of the molecular weight between crosslinking points of the cured product (α) formed by curing composition (α) to the molecular weight between crosslinking points of the cured product (αeq) formed by curing composition (α) (molecular weight between crosslinking points of cured product (α) / molecular weight between crosslinking points of cured product (αeq)) can be expressed by the following formula:

[0128] Ratio = {2×[1+μ(cured substance(α))]×ρ(cured substance(α))×R×[273+Tmin(cured substance(α))] / E'min(cured substance(α))} / {2×[1+μ(cured substance(αeq))]×ρ(cured substance(αeq))×R×[273+Tmin(cured substance(αeq))] / E'min(cured substance(αeq))}.

[0129] Here, the difference between cured product (α) and cured product (αeq) lies only in the content of component (C). The different contents of component (C) have little effect on the Poisson's ratio (μ) and specific gravity (ρ) of the cured product. Therefore, in the above formula, μ(cured product (α)) and μ(cured product (αeq)) can be considered as the same value, and ρ(cured product (α)) and ρ(cured product (αeq)) can be considered as the same value. As a result, the ratio of the molecular weight between crosslinking points of cured product (α) to the molecular weight between crosslinking points of cured product (αeq) (molecular weight between crosslinking points of cured product (α) / molecular weight between crosslinking points of cured product (αeq)) can be expressed by the following formula:

[0130] Ratio = {[273+Tmin(cured substance(α))] / E'min(cured substance(α))} / {[273+Tmin(cured substance(αeq))] / E'min(cured substance(αeq))} = {[273+Tmin(cured substance(α))] / [273+Tmin(cured substance(αeq))]}×E'min(cured substance(αeq)) / E'min(cured substance(α)).

[0131] In this specification, the aforementioned ratio is designated as "X". That is, the inventors conducted in-depth research and independently obtained the novel insight that by keeping the value of X within a specified range and using polymer particles, the toughness of the cured product is surprisingly excellent, thus completing this invention.

[0132] It should be noted that the evaluation of the molecular weight between crosslinking points should be based on the measured value of the cured product formed by curing the composition containing only components (A), (C), and (D). This is because components (A) and (C) are used to form the crosslinking structure, and component (D) can affect the progress of the crosslinking reaction. Conversely, when evaluating the molecular weight between crosslinking points, components other than (B) and (A) through (D) (e.g., inorganic fillers) cannot be added. This is because, although these components do not participate in the formation of crosslinks, they can affect the E'min and other parameters of the cured product formed by curing the composition, thus making it impossible to correctly evaluate the molecular weight between crosslinking points. It should be noted that component (D) is not incorporated into the crosslinking structure. Since it is a curing accelerator and its added amount is relatively small compared to the total amount of components (A) and (C), it is considered that the unreacted (D) component remaining after curing has a relatively small impact on the molecular weight between crosslinking points.

[0133] Previously, mechanical properties such as toughness were controlled by the type of component (A) in the cured resin composition, as well as the type and amount of other additives. However, the inventors of this invention have, for the first time, focused on the previously unaddressed molecular weight between the crosslinking points of the cured product, and solved the aforementioned problem by controlling this molecular weight within a specified range and using polymer particles, thus completing this invention. It should be noted that the conventional understanding was to disperse polymer particles (B) in component (A) (e.g., epoxy resin) to induce large-scale plastic deformation of the epoxy resin to consume energy, thereby improving toughness. This invention, however, proposes that by controlling the molecular weight between the crosslinking points within a specified range in the presence of polymer particles (B), plastic deformation of the cured product becomes easier, thereby significantly improving toughness. In other words, this technical concept of controlling the molecular weight between the crosslinking points within a specified range is a concept that could not have been conceived from the prior art.

[0134] <1-1-2.(A)Component>

[0135] (A) Substances containing epoxy groups. In this specification, "substances containing epoxy groups" refers to substances having one or more epoxy groups per molecule.

[0136] The epoxy-containing substance as component (A) includes at least one selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin. According to this scheme, the following advantages are available: the composition has relatively low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition exhibits excellent strength, elastic modulus, and heat resistance (high Tg).

[0137] In this specification, sometimes "a substance containing two or more epoxy groups in one molecule" is referred to as "a substance containing polyfunctional epoxy groups", and sometimes "a substance containing X epoxy groups in one molecule" is referred to as "a substance containing X functional epoxy groups".

[0138] (A) The bisphenol A type epoxy resin and bisphenol F type epoxy resin in component (A) are preferably each independently a substance containing polyfunctional epoxy groups, more preferably a substance containing difunctional epoxy groups. According to this scheme, the following advantages are available: a high degree of toughness improvement effect resulting from the control of molecular weight between crosslinking points. (A) The alicyclic epoxy resin in component (A) is preferably a substance containing polyfunctional epoxy groups, more preferably a substance containing difunctional epoxy groups. According to this scheme, the following advantages are available: the viscosity of the composition is particularly low and the processability is excellent; consequently, the toughness improvement effect resulting from the control of molecular weight between crosslinking points is high.

[0139] Examples of commercially available bisphenol A type epoxy resins include: products sold by Mitsubishi Chemical Corporation under the trademark jER (e.g., jER 828, jER 825, jER 827, jER 828EL, jER 828US, jER828XA, jER 834, jER 1001, jER 1002, jER 1004, jER 1007, jER 1009, jER 1010); products sold by Momentive SpeciAlty Chemicals under the trademark EPON (e.g., EPON 1510, EPON1310, EPON 828, EPON 872, EPON 1001, EPON 1004, EPON 2004); and products sold by Olin Epoxy under the trademark DER (e.g., DER 331, DER 332, DER 336, DER...). 439); products sold by ADEKA Corporation under the trademark ADEKARESIN (e.g., EP-4100, EP-4300, EP-4400, EP-4530, EP-4504); and products sold by DIC Corporation under the trademark EPICLON (e.g., EPICLON 840, EPICLON 850). But not limited to these.

[0140] Examples of commercially available bisphenol F type epoxy resins include: products sold by Mitsubishi Chemical Corporation under the trademark jER (e.g., jER 806, jER 806H, jER 807, jER 4005P, jER 4007P, jER4010P); products sold by Olin Epoxy under the trademark DER (e.g., DER 334); products sold by ADEKA Corporation under the trademark ADEKA RESIN (e.g., EP-4901, EP-4901E); and products sold by DIC Corporation under the trademark EPICLON (e.g., EPICLON 830). However, these are not exhaustive.

[0141] Alicyclic epoxy resins are compounds that (i) contain one or more saturated or unsaturated aliphatic hydrocarbon rings and (ii) contain one or more epoxy groups in their molecules, including, for example, epoxy resins containing cycloalkane rings. Examples of alicyclic epoxy resins include 3,4-epoxycyclohexyl methyl ester (3,4-epoxy)cyclohexanoate, tetrahydroindene diepoxide, vinylcyclohexene oxide, dipentene diepoxide, bis(3,4-epoxycyclohexylmethyl) adipic acid, dicyclopentadiene diepoxide, bis(2,3-epoxycyclopentyl) ether, 1,2-epoxy-4-(2-epoxyethylene)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol, and epoxidized... Butanetetracarboxylic acid tetra(3-cyclohexenylmethyl) modified ε-caprolactone, bis-7-oxabicyclo[4.1.0]heptane, dodecyl bisphenol A diglycidyl ether, dodecyl bisphenol F diglycidyl ether, 1,4-cyclohexanediethanol diglycidyl ether, hexahydrophthalic acid diglycidyl ester, hexahydroterephthalic acid diglycidyl ester, and 2,2-bis(4-hydroxycyclohexyl)propane diglycidyl ether (commonly known as: hydrogenated bisphenol A type liquid epoxy resin), etc. The alicyclic epoxy resin preferably comprises one or more selected from (3,4-epoxy)cyclohexanoic acid 3,4-epoxycyclohexyl methyl ester, 1,2-epoxy-4-(2-epoxyethylene)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol, tetra-(3-cyclohexenylmethyl)-modified ε-caprolactone of epoxide tetracarboxylic acid, and diglycidyl ether of 2,2-bis(4-hydroxycyclohexyl)propane, more preferably composed of only one or more selected from these, further preferably comprising (3,4-epoxy)cyclohexanoic acid 3,4-epoxycyclohexyl methyl ester, and even more preferably composed of only (3,4-epoxy)cyclohexanoic acid 3,4-epoxycyclohexyl methyl ester. According to this embodiment, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg).

[0142] In component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight, preferably 65 to 100 parts by weight, more preferably 70 to 100 parts by weight, even more preferably 71 to 100 parts by weight, even more preferably 80 to 100 parts by weight, further preferably 90 to 100 parts by weight, and particularly preferably 95 to 100 parts by weight. In component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight may also be less than 100 parts by weight. According to this scheme, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg). In component (A), the total content of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin in 100 parts by weight can also be 100 parts by weight. In other words, component (A) can consist only of bisphenol A type epoxy resin, or only of bisphenol F type epoxy resin, or only of alicyclic epoxy resin, or only of bisphenol A type epoxy resin and alicyclic epoxy resin, or only of bisphenol F type epoxy resin and alicyclic epoxy resin, or only of bisphenol A type epoxy resin and bisphenol F type epoxy resin, or only of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin. Component (A) may also not contain other epoxy-containing substances described below (e.g., glycidylamine type epoxy resin, etc.).

[0143] (A) In addition to containing one or more types of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin, the component may also contain epoxy-containing substances other than bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin. In this specification, "epoxy-containing substances other than bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin" is sometimes referred to as "other epoxy-containing substances." Examples of other epoxy-containing substances include (i) substances containing polyfunctional epoxy groups other than bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin, and (ii) substances containing monofunctional epoxy groups other than alicyclic epoxy resin. In this specification, "substances containing polyfunctional epoxy groups other than bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin" is sometimes referred to as "other polyfunctional epoxy-containing substances." In addition, in this specification, "substances containing monofunctional epoxy groups other than alicyclic epoxy resins" are sometimes referred to as "other substances containing monofunctional epoxy groups".

[0144] (A) The composition may also be (i) composed solely of bisphenol A type epoxy resin and other epoxy-containing substances, (ii) composed solely of bisphenol F type epoxy resin and other epoxy-containing substances, (iii) composed solely of alicyclic epoxy resin and other epoxy-containing substances, (iv) composed solely of bisphenol A type epoxy resin, alicyclic epoxy resin and other epoxy-containing substances, (v) composed solely of bisphenol F type epoxy resin, alicyclic epoxy resin and other epoxy-containing substances, (vi) composed solely of bisphenol A type epoxy resin, bisphenol F type epoxy resin and other epoxy-containing substances, (vii) composed solely of bisphenol A type epoxy resin and other epoxy-containing substances, or (vii) composed solely of bisphenol A type epoxy resin, bisphenol F type epoxy resin, alicyclic epoxy resin and other epoxy-containing substances.

[0145] Other substances containing polyfunctional epoxy groups are not particularly limited. Examples of other substances containing polyfunctional epoxy groups include commonly used epoxy resins other than bisphenol A type epoxy resins, bisphenol F type epoxy resins, and alicyclic epoxy resins, as well as the following: bisphenol AD ​​type epoxy resins, bisphenol S type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenolic varnish type epoxy resins, biphenyl type epoxy resins, oxazolidinone type epoxy resins, biphenyl aralkyl type epoxy resins, bis(naphthalene) type epoxy resins, glycidyl ether type epoxy resins of bisphenol A glycidyl oxide adducts, hydrogenated bisphenol A type epoxy resins, hydrogenated bisphenol F type epoxy resins, fluorinated epoxy resins, flame-retardant epoxy resins such as tetrabromobisphenol A glycidyl ether, and so on. Epoxy benzoate glycidyl ether ester type epoxy resin, m-aminophenol type epoxy resin, diaminodiphenylmethane type epoxy resin, N,N-diglycidyl aniline, N,N-diglycidyl-o-toluidine, triglycidyl isocyanurate, divinylbenzene dioxide, resorcinol diglycidyl ether, polyalkylene glycol diglycidyl ether, glycol diglycidyl ether, diglycidyl ester of aliphatic polyacid, glycidyl ether of di- or higher aliphatic polyols such as glycerol, chelated modified epoxy resin, rubber modified epoxy resin, polyurethane modified epoxy resin, hydantoin type epoxy resin, unsaturated polymer epoxides such as petroleum resin, and amino-containing glycidyl ether resins.

[0146] Epoxy compounds obtained by adding bisphenol A (or F) or polybasic acids to epoxy resins such as bisphenol A type epoxy resin are also classified as other substances containing polyfunctional epoxy groups (i.e., other substances containing epoxy groups).

[0147] Examples of glycidylamine type epoxy resins include N,N,O-triglycidyl-m-aminophenol, N,N,O-triglycidyl-p-aminophenol, N,N,O-triglycidyl-4-amino-3-methylphenol, N,N,N',N'-tetraglycidyl-4,4'-methylenediphenylamine, N,N,N',N'-tetraglycidyl-2,2'-diethyl-4,4'-methylenediphenylamine, N,N,N',N'-tetraglycidyl-m-xylenediamine, N,N-diglycidylaniline, and N,N-diglycidyl-o-toluidine. Examples of polyalkylene glycol diglycidyl ethers include polyethylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether. Examples of diglycidyl ethers of diols include neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and cyclohexanediethanol diglycidyl ether. Examples of diglycidyl esters of aliphatic polyacids include dimer diglycidyl esters, adipic acid diglycidyl esters, sebacic acid diglycidyl esters, and maleic acid diglycidyl esters. Examples of diglycidyl ethers of di- or higher aliphatic polyols include trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, castor oil-modified polyglycidyl ether, propoxylated glycerol triglycidyl ether, and sorbitol polyglycidyl ether.

[0148] As the chelated modified epoxy resin, for example, the resin described in paragraphs

[0018] to

[0019] of the publication booklet No. WO2016-163491 can be used.

[0149] The rubber-modified epoxy resin is a reaction product obtained by reacting rubber with an epoxy-containing compound, having an average of 1.1 or more, preferably 2 or more, epoxy groups per molecule. For example, the resin described in paragraphs

[0124] to

[0132] of the publication WO2016-163491 can be used as the rubber-modified epoxy resin.

[0150] As the polyurethane-modified epoxy resin, for example, the resin described in paragraphs

[0133] to

[0135] of the publication booklet No. WO2016-163491 can be used.

[0151] As an epoxy compound obtained by adding polybasic acids to epoxy resins such as bisphenol A type epoxy resin, an example is the addition reaction product obtained by reacting tall oil fatty acid dimers (dimer acids) with bisphenol A type epoxy resin as described in International Publication No. 2010-098950.

[0152] Other substances containing monofunctional epoxy groups include, for example: aliphatic glycidyl ethers (e.g., butyl glycidyl ether); aromatic glycidyl ethers (e.g., phenyl glycidyl ether, tolyl glycidyl ether (e.g., o-tolyl glycidyl ether)); ethers composed of an alkyl group having 8 to 10 carbon atoms and a glycidyl group (e.g., 2-ethylhexyl glycidyl ether); and ethers composed of a phenyl group having 6 to 12 carbon atoms that is allowed to be substituted by an alkyl group having 2 to 8 carbon atoms and a glycidyl group (e.g., p-tert-butyl glycidyl ether). Phenyl glycidyl ether, etc.; ethers composed of alkyl groups and glycidyl groups having 12 to 14 carbon atoms (also known as alkyl C12-C14 glycidyl ethers) (e.g., dodecyl glycidyl ether, etc.); aliphatic glycidyl esters (e.g., glycidyl (meth)acrylate, glycidyl maleate, etc.); glycidyl esters of aliphatic carboxylic acids having 8 to 12 carbon atoms (e.g., glycidyl petrolatum, glycidyl neodecanoate, glycidyl laurate, etc.); glycidyl p-tert-butylbenzoate; etc.

[0153] As other epoxy-containing substances, one of the above substances can be used alone, or two or more can be used together.

[0154] Regarding these other epoxy-containing substances, component (A) preferably includes one or more selected from glycidylamine type epoxy resin, biphenyl type epoxy resin, oxazolidinone type epoxy resin, biphenyl aralkyl type epoxy resin, bis(naphthyl) type epoxy resin, phenolic varnish type epoxy resin, and diol diglycidyl ether; more preferably, it includes one or more selected from glycidylamine type epoxy resin, biphenyl aralkyl type epoxy resin, oxazolidinone type epoxy resin, biphenyl aralkyl type epoxy resin, bis(naphthyl) type epoxy resin, and diol diglycidyl ether; even more preferably, it includes one or more selected from glycidylamine type epoxy resin, biphenyl aralkyl type epoxy resin, oxazolidinone type epoxy resin, and diol diglycidyl ether; and particularly preferably, it includes one or more selected from glycidylamine type epoxy resin, biphenyl type epoxy resin, and diol diglycidyl ether. According to this scheme, the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg).

[0155] The following description refers to the case where component (A) contains one or more selected from glycidylamine type epoxy resin, biphenyl type epoxy resin, oxazolidinone type epoxy resin, biphenyl aralkyl type epoxy resin, bis(naphthalene) type epoxy resin, phenolic varnish type epoxy resin, and diglycidyl glycol ether. In component (A), the total content of glycidylamine type epoxy resin, biphenyl type epoxy resin, oxazolidinone type epoxy resin, biphenyl aralkyl type epoxy resin, bis(naphthalene) type epoxy resin, phenolic varnish type epoxy resin, and diglycidyl glycol ether is preferably 29 parts by mass or less, more preferably 24 parts by mass or less, and particularly preferably 19 parts by mass or less. According to this scheme, it has the following advantages: the composition has relatively low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg). (A) The lower limit of the total content of glycidylamine type epoxy resin, biphenyl type epoxy resin, oxazolidinone type epoxy resin, biphenyl aralkyl type epoxy resin, bis(naphthalene) type epoxy resin, phenolic varnish type epoxy resin, and diol diglycidyl ether in the composition is not particularly limited, but may, for example, exceed 0 parts by mass, be more than 1 part by mass, be more than 2 parts by mass, or be more than 3 parts by mass. According to this scheme, the following advantages are available: the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg).

[0156] (A) Component may or may not contain glycidylamine type epoxy resin. The following describes the case where component (A) contains glycidylamine type epoxy resin. The content of glycidylamine type epoxy resin in component (A) is preferably 29 parts by mass or less, more preferably 24 parts by mass or less, further preferably 19 parts by mass or less, and particularly preferably 14 parts by mass or less. According to this scheme, it has the following advantages: the composition has relatively low viscosity and excellent processability; furthermore, the cured product obtained by curing this composition has excellent strength, elastic modulus, and heat resistance (high Tg). The lower limit of the content of glycidylamine type epoxy resin in component (A) is not particularly limited, but for example, it can exceed 0 parts by mass, can be 1 part by mass or more, can be 2 parts by mass or more, or can be 3 parts by mass or more. According to this scheme, it has the following advantages: the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg).

[0157] In this specification, the term "substances containing polyfunctional epoxy groups" is sometimes used to refer to "substances containing polyfunctional epoxy groups with an epoxy equivalent of 300 g / eq or more but less than 3000 g / eq", or "substances containing polyfunctional epoxy groups with an epoxy equivalent of 300 g / eq or more but less than 3000 g / eq and having two or more epoxy groups in one molecule".

[0158] In this specification, epoxy equivalent refers to the molecular weight of each epoxy group in a substance containing epoxy groups, specifically calculated based on the following formula.

[0159] Epoxy equivalent (g / eq) = mass-average molecular weight (Mw) of the epoxy-containing substance / average number of epoxy groups per molecule of the epoxy-containing substance (average number).

[0160] In addition, epoxy equivalent can also be determined according to JISK 7236.

[0161] Component (A) may or may not contain a substance with polyfunctional epoxy groups (a1). Considering the advantage of achieving a relatively low viscosity and excellent processability of the composition, component (A) preferably does not contain a substance with polyfunctional epoxy groups (a1).

[0162] Considering the excellent toughness of the cured product obtained by curing the composition, component (A) preferably contains a substance containing polyfunctional epoxy groups (a1). Here, (i) a bisphenol A type epoxy resin with an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups per molecule, (ii) a bisphenol F type epoxy resin with an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups per molecule, and (iii) an alicyclic epoxy resin with an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups per molecule are all substances containing polyfunctional epoxy groups (a1). In 100 parts by weight of component (A), the content of the substance (a1) containing polyfunctional epoxy groups is preferably 5 to 100 parts by weight, more preferably 6 to 50 parts by weight, further preferably 7 to 30 parts by weight, and particularly preferably 8 to 20 parts by weight. According to this scheme, it has the following advantages: the composition has relatively low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent toughness. In 100 parts by weight of component (A), the content of the substance (a1) containing polyfunctional epoxy groups may also be less than 100 parts by weight.

[0163] In this specification, "substances containing monofunctional epoxy groups" are sometimes referred to as "substances containing monofunctional epoxy groups (a2)". In addition, "substances containing monofunctional epoxy groups" are sometimes also referred to as "monoepoxides".

[0164] (A) Component may contain a substance (a2) with a monofunctional epoxy group, or it may not contain such a substance. Considering the advantage that the cured product obtained by curing the composition has excellent strength and heat resistance (high Tg), (A) component preferably does not contain a substance (a2) with a monofunctional epoxy group.

[0165] (A) Component preferably contains a substance (a2) containing a monofunctional epoxy group. According to this scheme, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent toughness. In 100 parts by weight of component (A), the content of the monofunctional epoxy group-containing substance (a2) is preferably 5 to 40 parts by weight, more preferably 5 to 35 parts by weight, even more preferably 5 to 33 parts by weight, and particularly preferably 5 to 30 parts by weight. According to this scheme, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength and / or toughness. In 100 parts by weight of component (A), the content of the monofunctional epoxy group-containing substance (a2) may also be less than 40 parts by weight.

[0166] Considering the advantage that the cured product obtained by curing the composition has superior toughness, component (A) preferably contains a substance containing polyfunctional epoxy groups (a1) and a substance containing monofunctional epoxy groups (a2). The following describes the case where component (A) contains a substance containing polyfunctional epoxy groups (a1) and a substance containing monofunctional epoxy groups (a2). At this point, in 100 parts by mass of component (A), preferably (i) the content of the substance (a1) containing polyfunctional epoxy groups is 5 parts by mass to 95 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 40 parts by mass; more preferably (ii) the content of the substance (a1) containing polyfunctional epoxy groups is 6 parts by mass to 50 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 35 parts by mass; further preferably (iii) the content of the substance (a1) containing polyfunctional epoxy groups is 7 parts by mass to 30 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 33 parts by mass; especially preferably (iv) the content of the substance (a1) containing polyfunctional epoxy groups is 8 parts by mass to 20 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 30 parts by mass. According to this scheme, the following advantages are available: the composition has low viscosity and excellent processability, and the cured product obtained by curing the composition has excellent strength and / or toughness. If component (A) contains a substance containing a polyfunctional epoxy group (a1) and a substance containing a monofunctional epoxy group (a2), then in 100 parts by mass of component (A), (i) the content of the substance containing the polyfunctional epoxy group (a1) may be less than 95 parts by mass, and / or (ii) the content of the substance containing the monofunctional epoxy group (a2) may be less than 40 parts by mass.

[0167] Polyalkylene glycol diglycidyl ether, glycol diglycidyl ether, diglycidyl esters of aliphatic polyacids, and glycidyl ethers of di- or higher aliphatic polyols can also be considered epoxy resins with relatively low viscosity. These "epoxy resins with relatively low viscosity" are sometimes referred to as "polyepoxides" in this specification. When polyepoxides are used in combination with epoxy resins other than polyepoxides (e.g., bisphenol A type epoxy resins and / or bisphenol F type epoxy resins, etc.), the polyepoxide acts as a reactive diluent in the composition, thereby improving the balance between the viscosity of the composition and the properties of the cured product. Furthermore, when epoxy resins other than polyepoxides (e.g., bisphenol A type epoxy resins and / or bisphenol F type epoxy resins, etc.) are used in combination with a substance containing monofunctional epoxy groups (a2), the monofunctional epoxy group-containing substance (a2) acts as a reactive diluent in the composition, thereby improving the balance between the viscosity of the composition and the properties of the cured product.

[0168] The component (A) preferably contains a monofunctional epoxy group-containing substance (a2) and / or a polyepoxide as a reactive diluent. In component (A), the total content of the monofunctional epoxy group-containing substance (a2) and the polyepoxide is preferably 0.5 parts by mass to 30.0 parts by mass per 100 parts by mass of component (A), more preferably 2.0 parts by mass to 20.0 parts by mass, and even more preferably 5.0 parts by mass to 15.0 parts by mass.

[0169] Regarding the epoxy-containing substance as component (A), it may comprise an epoxy-containing substance with an epoxy equivalent of less than 220 g / eq, or it may consist solely of an epoxy-containing substance with an epoxy equivalent of less than 220 g / eq. It may also comprise an epoxy-containing substance with an epoxy equivalent of 90 g / eq or more but less than 210 g / eq, or it may consist solely of an epoxy-containing substance with an epoxy equivalent of 90 g / eq or more but less than 210 g / eq, or it may consist solely of an epoxy-containing substance with an epoxy equivalent of 135 g / eq or more but less than 200 g / eq. According to this scheme, the following advantages are achieved: a cured product with high elastic modulus and high heat resistance can be obtained.

[0170] Among various epoxy-containing substances, bisphenol A type epoxy resin and bisphenol F type epoxy resin are relatively inexpensive, and the cured products obtained using them have high elastic modulus and excellent heat resistance and adhesion. Therefore, component (A) preferably contains bisphenol A type epoxy resin and / or bisphenol F type epoxy resin, more preferably it consists only of bisphenol A type epoxy resin and / or bisphenol F type epoxy resin. In addition, from the viewpoint of being able to obtain a curable resin composition that provides a cured product with excellent heat resistance at a low cost, component (A) more preferably contains bisphenol A type epoxy resin, and particularly preferably it consists only of bisphenol A type epoxy resin.

[0171] In component (A), the total content of bisphenol A type epoxy resin and bisphenol F type epoxy resin in 100 parts by weight is preferably 60 parts by weight or more, more preferably 80 parts by weight or more, and even more preferably 90 parts by weight or more. According to this scheme, the cured product has the following advantages: the obtained product has superior toughness, impact resistance, heat resistance, and strength. In component (A), the total content of bisphenol A type epoxy resin and bisphenol F type epoxy resin in 100 parts by weight can be 100 parts by weight. In other words, component (A) can be (i) composed only of bisphenol A type epoxy resin, or (ii) composed only of a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin.

[0172] Both bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq are liquid at room temperature, thus exhibiting excellent workability. Therefore, from the viewpoint that the composition can achieve even better workability and storage stability, component (A) is more preferably composed of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and / or bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq, and particularly preferably a mixture of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq.

[0173] In component (A), the total content of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq is preferably 60 parts by weight or more, more preferably 80 parts by weight or more, and even more preferably 90 parts by weight or more. According to this scheme, it has the following advantages: the composition is superior in terms of workability and storage stability, and the cured product obtained by curing the composition is superior in terms of toughness, impact resistance, heat resistance, and strength. In component (A), the total content of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq can be 100 parts by weight. In other words, component (A) can be (i) composed solely of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq, or (ii) composed solely of a mixture of bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq and bisphenol F type epoxy resin with an epoxy equivalent of less than 220 g / eq.

[0174] The content of component (A) in the composition is preferably 20 parts by mass or more, more preferably 25 parts by mass or more, further preferably 30 parts by mass or more, and particularly preferably 35 parts by mass or more, in 100 parts by mass of the composition. According to this scheme, the cured product obtained by curing the composition has excellent strength and / or toughness.

[0175] When component (C) in the composition is an acid anhydride (C1), the composition preferably (i) contains an alicyclic epoxy resin as component (A), more preferably (ii) contains a polyfunctional alicyclic epoxy resin having two or more epoxy groups in one molecule as component (A), and even more preferably (iii) contains a polyfunctional alicyclic epoxy resin having an epoxy equivalent of less than 220 g / eq (or more than 90 g / eq and less than 220 g / eq) and having two or more epoxy groups in one molecule as component (A). When component (C) in the composition is an acid anhydride (C1), it is preferable that (i) the content of alicyclic epoxy resin in the composition is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A), more preferably (ii) the content of polyfunctional alicyclic epoxy resin having two or more epoxy groups in one molecule is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A), and even more preferably (iii) the epoxy equivalent is less than 220 g / eq (or more than 90 g / eq but less than 220 g / eq) and the polyfunctional alicyclic epoxy resin having two or more epoxy groups in one molecule is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A).

[0176] A preferred embodiment of the present invention is as follows.

[0177] A curable resin composition,

[0178] It contains the following components: (A), (B), and (C).

[0179] And it does not contain the following ingredient (D) or contains the following ingredient (D),

[0180] (A) Components: A substance containing epoxy groups, including alicyclic epoxy resin (preferably a polyfunctional alicyclic epoxy resin having two or more epoxy groups in one molecule, more preferably a polyfunctional alicyclic epoxy resin with an epoxy equivalent of less than 220 g / eq (or more than 90 g / eq and less than 220 g / eq) and having two or more epoxy groups in one molecule).

[0181] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0182] (C) Component: Acid anhydride (c1);

[0183] (D) Ingredient: Curing accelerator,

[0184] Of 100 parts by weight of component (A), the content of the alicyclic epoxy resin is 60 to 100 parts by weight (or more than 60 parts by weight but less than 100 parts by weight).

[0185] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0186] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0187] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0188] The value X of the curable resin composition, calculated from the aforementioned formula, is 1.05 to 5.50.

[0189] When component (C) in the composition is an aromatic amine (C2) or an alicyclic amine (C3), the composition preferably (i) contains a bisphenol A type epoxy resin as component (A), more preferably (ii) contains a polyfunctional bisphenol A type epoxy resin having two or more epoxy groups in one molecule as component (A), and even more preferably (iii) contains a polyfunctional bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq (or more than 90 g / eq and less than 220 g / eq) and having two or more epoxy groups in one molecule as component (A). When component (C) in the composition is an aromatic amine (C2) or an alicyclic amine (C3), it is preferable that (i) the content of bisphenol A type epoxy resin is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A), more preferably (ii) the content of polyfunctional bisphenol A type epoxy resin having two or more epoxy groups in one molecule is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A), and even more preferably (iii) the epoxy equivalent is less than 220 g / eq (or more than 90 g / eq but less than 220 g / eq) and the content of polyfunctional bisphenol A type epoxy resin having two or more epoxy groups in one molecule is 60 to 100 parts by mass (or more than 60 parts by mass but less than 100 parts by mass) per 100 parts by mass of component (A).

[0190] A preferred embodiment of the present invention is as follows.

[0191] A curable resin composition,

[0192] It contains the following components: (A), (B), and (C).

[0193] And it does not contain the following ingredient (D) or contains the following ingredient (D),

[0194] (A) Components: A substance containing epoxy groups, which includes bisphenol A type epoxy resin (preferably a polyfunctional bisphenol A type epoxy resin having two or more epoxy groups in one molecule, more preferably a polyfunctional bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq (or more than 90 g / eq and less than 220 g / eq) and having two or more epoxy groups in one molecule);

[0195] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0196] Component (C): Aromatic amine (C2);

[0197] (D) Ingredient: Curing accelerator,

[0198] Of 100 parts by weight of component (A), the content of bisphenol A type epoxy resin is 60 to 100 parts by weight (or more than 60 parts by weight but less than 100 parts by weight).

[0199] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0200] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0201] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0202] The value X of the curable resin composition, calculated from the aforementioned formula, is 1.30 to 9.00.

[0203] A preferred embodiment of the present invention is as follows.

[0204] A curable resin composition,

[0205] It contains the following components: (A), (B), and (C).

[0206] And it does not contain the following ingredient (D) or contains the following ingredient (D),

[0207] (A) Components: A substance containing epoxy groups, which includes bisphenol A type epoxy resin (preferably a polyfunctional bisphenol A type epoxy resin having two or more epoxy groups in one molecule, more preferably a polyfunctional bisphenol A type epoxy resin with an epoxy equivalent of less than 220 g / eq (or more than 90 g / eq and less than 220 g / eq) and having two or more epoxy groups in one molecule);

[0208] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0209] (C) Component: Alicyclic amine (C3);

[0210] (D) Ingredient: Curing accelerator,

[0211] Of 100 parts by weight of component (A), the content of bisphenol A type epoxy resin is 60 to 100 parts by weight (or more than 60 parts by weight but less than 100 parts by weight).

[0212] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0213] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0214] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0215] The value X of the curable resin composition, calculated from the aforementioned formula, is 1.30 to 9.00.

[0216] <1-1-3.(B) Component>

[0217] (B) The component is a polymer particle having a core-shell structure comprising a core layer and a shell layer. In this specification, "polymer particle having a core-shell structure comprising a core layer and a shell layer" means a particle with a layered structure formed by a core layer comprising a core polymer and a shell layer comprising a shell polymer. In this specification, "polymer particle having a core-shell structure comprising a core layer and a shell layer" is sometimes referred to as "core-shell polymer particle" or simply "polymer particle".

[0218] Component (B) (polymer particles) in the composition can improve toughness. In other words, the composition has the advantage of providing a cured product with excellent toughness by including component (B). In addition, the composition tends to have excellent strength in the resulting cured product by including component (B).

[0219] Polymer particles can be obtained by grafting copolymerizable monomers (shell-forming monomers) in the presence of a core layer to form a shell. More specifically, this polymerization operation can be carried out by adding shell-forming monomers to a latex of a core polymer that has been prepared as an aqueous polymer latex and polymerizing it. In the polymer particles, it is preferable that the core polymer and the shell polymer are substantially chemically bonded. Here, in the polymer particles, the core layer and the shell layer may not be formed as a completely layered structure. The shell layer (shell polymer) only needs to cover at least a portion of the core layer (core polymer), without completely covering the core layer. In addition, a portion of the shell layer may extend into the interior of the core layer.

[0220] The following is a detailed description of each layer of the polymer particles.

[0221] The Core Layer

[0222] To improve the toughness of the cured composition, the core layer is preferably an elastic core layer with rubber-like properties.

[0223] From the aspects of high toughness improvement effect of the obtained cured product, high impact resistance improvement effect of the obtained cured product, and low affinity with component (A) making it difficult for viscosity increase with time caused by core layer swelling to occur, the core layer preferably contains diene rubber, more preferably diene rubber (e.g., composed only of diene rubber).

[0224] From the viewpoint of designing polymers with a wide range of options through combinations of various monomers, the core layer preferably contains a (meth)acrylate rubber. Furthermore, if it is desired to improve the impact resistance at low temperatures without reducing the heat resistance of the cured product, the core layer preferably contains an organosiloxane rubber. In other words, the core layer preferably contains one or more types selected from diene rubbers, (meth)acrylate rubbers, and organosiloxane rubbers.

[0225] (Diene-based rubber)

[0226] The diene rubber is preferably a polymer containing 50% to 100% by mass of conjugated diene units and 0% to 50% by mass of structural units derived from vinyl monomers other than conjugated diene monomers that can copolymerize with conjugated diene monomers.

[0227] Examples of conjugated diene monomers that are sources of the conjugated diene units include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), and 2-chloro-1,3-butadiene.

[0228] These conjugated diene monomers can be used alone or in combination of two or more.

[0229] The content of conjugated diene units in the core layer is preferably 50% to 100% by mass of all structural units constituting the core layer, more preferably 70% to 100% by mass, and even more preferably 90% to 100% by mass. When the content of conjugated diene units in the core layer is 50% by mass or more, the toughness of the resulting cured product may be better.

[0230] Vinyl monomers other than conjugated diene monomers that can copolymerize with conjugated diene monomers include, for example: vinyl aromatics such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; vinyl carboxylic acids such as acrylic acid and methacrylic acid; vinyl cyanides such as acrylonitrile and methacrylonitrile; halogenated vinyls such as vinyl chloride, vinyl bromide, and chloroprene; ethyl acetate; alkenes such as ethylene, propylene, butene, and isobutene; and multifunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene; etc.

[0231] These vinyl monomers can be used alone or in combination of two or more. Styrene is particularly preferred as a vinyl monomer that can copolymerize with conjugated diene monomers, in addition to conjugated diene monomers.

[0232] From the perspectives of improved toughness, improved impact resistance, and reduced viscosity increase over time due to core layer swelling caused by low affinity for epoxy resin (component (A)), the core layer preferably comprises a homopolymer of 1,3-butadiene, i.e., butadiene rubber, and / or a copolymer of 1,3-butadiene and styrene, i.e., butadiene-styrene rubber. More preferably, it comprises butadiene rubber, and / or butadiene-styrene rubber (e.g., composed only of butadiene rubber and / or butadiene-styrene rubber). Further preferably, it comprises butadiene rubber, and especially preferably, it comprises butadiene rubber (e.g., composed only of butadiene rubber). In addition, butadiene-styrene rubber is preferred because it can be used to adjust the refractive index to improve the transparency of the resulting cured product.

[0233] ((meth)acrylate rubber)

[0234] The (meth)acrylate-based rubber is preferably a polymer obtained by polymerizing a mixture of monomers containing 50% to 100% by mass of (meth)acrylate units and 0% to 50% by mass of structural units derived from vinyl monomers other than (meth)acrylate monomers that are capable of copolymerizing with (meth)acrylate monomers. Here, in this specification, "(meth)acrylate" refers to acrylates and / or methacrylates.

[0235] Regarding the (meth)acrylate monomers that are the source of the aforementioned (meth)acrylate units, examples include: (i) methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, dodecyl methacrylate, stearyl methacrylate, dodecyl methacrylate, etc., which are alkyl methacrylates; (ii) aromatic ring-containing (meth)acrylates such as phenoxyethyl methacrylate and benzyl methacrylate; iii) Hydroxyalkyl methacrylates; (iv) Glycidyl methacrylate, glycidyl methacrylate, and other glycidyl methacrylates; (v) Alkoxyalkyl methacrylates; (vi) Allyl methacrylate, allyl methacrylate, and other allyl methacrylates; (vii) Polyfunctional methacrylates such as monoethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate; etc.

[0236] Examples of hydroxyalkyl methacrylates include: 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, and other hydroxyl linear alkyl methacrylates (especially hydroxyl linear C1-6 alkyl methacrylates); caprolactone-modified hydroxy(meth)acrylates; methyl α-(hydroxymethyl)acrylate, ethyl α-(hydroxymethyl)acrylate, and other hydroxyl branched alkyl methacrylates; and hydroxyl-containing (meth)acrylate monoesters of polyester diols (especially saturated polyester diols) obtained from dicarboxylic acids (phthalic acid, etc.) and diols (propylene glycol, etc.).

[0237] These (meth)acrylate monomers can be used alone or in combination of two or more. As (meth)acrylate units, they are preferably selected from one or more of (meth)acrylate units, (meth)acrylate units, and 2-ethylhexyl (meth)acrylate units.

[0238] Vinyl monomers that can copolymerize with (meth)acrylate monomers, other than (meth)acrylate monomers, include, for example: (i) vinyl aromatics such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; (ii) vinyl carboxylic acids such as acrylic acid and methacrylic acid; (iii) vinyl cyanides such as acrylonitrile and methacrylonitrile; (iv) halogenated vinyls such as vinyl chloride, vinyl bromide, and chloroprene; (v) ethyl acetate; (vi) alkenes such as ethylene, propylene, butene, and isobutene; (vii) multifunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene; etc.

[0239] Vinyl monomers other than (meth)acrylate monomers that can copolymerize with (meth)acrylate monomers can be used alone or in combination of two or more. From the viewpoint of easily increasing the refractive index, styrene is particularly preferred as a vinyl monomer other than (meth)acrylate monomers that can copolymerize with (meth)acrylate monomers.

[0240] (Organosiloxane-based rubber)

[0241] Examples of organosiloxane rubbers include: (i) polysiloxane polymers composed of siloxane units that have undergone di-substituted alkyl or aryl groups, such as dimethylsiloxane, diethylsiloxane, methylphenylsiloxane, diphenylsiloxane, and dimethylsiloxane-diphenylsiloxane; (ii) polysiloxane polymers composed of siloxane units that have undergone mono-substituted alkyl or aryl groups, such as organohydrogenated siloxane units where a portion of the alkyl group on the side chain has been replaced by a hydrogen atom; etc.

[0242] These polysiloxane polymers can be used alone or in combination of two or more. Among them, dimethylsiloxy, methylphenylsiloxy, and dimethylsiloxy-diphenylsiloxy are preferred because they can impart heat resistance to the cured product. From the viewpoint of easy availability, dimethylsiloxy is the most preferred.

[0243] The following describes the case where the core layer of the polymer particles contains diene rubber or is composed solely of diene rubber (hereinafter referred to as "Case A"). In Case A, the diene rubber preferably comprises butadiene rubber and / or butadiene-styrene rubber. According to this approach, there are advantages such as: (i) the cured product obtained by curing the composition has better toughness, (ii) the cured product has better impact resistance, and (iii) the viscosity increase over time caused by core layer swelling is less likely to occur due to the low affinity with component (A). From the viewpoint of this advantage, in Case A, the diene rubber preferably comprises 60 parts by mass or more, more preferably 70 parts by mass or more, further preferably 80 parts by mass or more, and particularly preferably 90 parts by mass or more of the diene rubber in 100 parts by mass: butadiene rubber, butadiene-styrene rubber, or a mixture of butadiene rubber and butadiene-styrene rubber. In Case A, the diene rubber may be composed solely of butadiene rubber and / or butadiene-styrene rubber. The core layer of the polymer particles may consist solely of butadiene rubber and / or butadiene-styrene rubber.

[0244] To improve the toughness of the resulting cured product, the glass transition temperature (hereinafter sometimes simply referred to as "Tg") of the core layer is preferably below 0°C, more preferably below -20°C, even more preferably below -40°C, and particularly preferably below -60°C. The glass transition temperature of the core layer can be determined by differential scanning calorimetry (DSC).

[0245] The volume average particle size of the core layer is not particularly limited, but is preferably 0.03 μm to 2.00 μm, more preferably 0.05 μm to 1.00 μm, even more preferably 0.12 μm to 0.50 μm, even more preferably 0.12 μm to 0.28 μm, and even more preferably 0.14 to 0.25 μm. Within this range, the core layer can be stably manufactured, and the cured product exhibits good heat resistance and toughness. The method for determining the volume average particle size of the core layer will be described in detail in the following examples.

[0246] The core layer can be a single-layer structure or a multi-layer structure (e.g., a multi-layer structure composed of layers with rubber elasticity). Furthermore, in the case of a multi-layer core layer, the polymer components of each layer can also differ within the scope of the foregoing disclosure.

[0247] The composition of the structural units of the core layer depends on the composition of the monomer mixture used to form the core layer (monomer mixture for core layer formation). With a polymerization conversion of 100%, the resulting core layer contains structural units derived from all the monomers contained in the monomer mixture for core layer formation.

[0248] In one embodiment of the present invention, an intermediate layer, such as those described in

[0046] to

[0049] of WO 2016-163491, may also be provided between the core layer and the shell layer.

[0249] Shell

[0250] The shell is a polymer obtained by polymerizing the shell-forming monomers. The polymer constituting the shell (shell polymer) serves to improve the compatibility between the polymer particles and component (A), thereby enabling the polymer particles to be dispersed in the composition and / or the cured product of the composition as primary particles.

[0251] The types and proportions of structural units contained in the shell are not particularly limited. From the viewpoint of the compatibility and dispersibility of polymer particles in the composition, the shell preferably contains one or more structural units selected from aromatic vinyl units, vinyl cyanide units, and (meth)acrylate units, and more preferably contains (meth)acrylate units. In particular, the shell preferably contains methyl methacrylate units.

[0252] The composition of the structural units of the shell depends on the composition of the monomer used to form the shell. When the polymerization conversion rate is 100%, the resulting shell contains structural units derived from all the monomers contained in the monomer used to form the shell.

[0253] The total content of one or more structural units selected from aromatic vinyl units, vinyl cyanide units and (meth)acrylate units in the shell is preferably 10.0% to 99.5% by mass in 100% by mass of the shell (shell polymer), more preferably 50.0% to 99.0% by mass, even more preferably 65.0% to 98.0% by mass, particularly preferably 67.0% to 80.0% by mass, and most preferably 67.0% to 85.0% by mass.

[0254] Specific examples of aromatic vinyl monomers that are sources of the aromatic vinyl units include vinylbenzenes such as styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene.

[0255] Specific examples of vinyl cyanide monomers that are sources of the vinyl cyanide units include acrylonitrile and methacrylonitrile.

[0256] Specific examples of (meth)acrylate monomers that are the source of the (meth)acrylate units are the same as those mentioned in the aforementioned "Core Layer" section, therefore the relevant records are cited and their descriptions are omitted here.

[0257] To maintain good dispersion and prevent polymer particles from agglomerating in the cured product and composition, it is preferable that the polymer particles are chemically bonded to component (A). To achieve this chemical bonding, the shell preferably has structural units derived from monomers containing reactive groups. In other words, the shell preferably contains reactive groups.

[0258] As a reactive group, it is preferably selected from one or more of epoxy group, oxetyl group, hydroxyl group, amino group, imide group, carboxylic acid group, carboxylic anhydride group, cyclic ester group, cyclic amide group, benzoxazin group and cyanate group.

[0259] The reactive groups are preferably epoxy groups. In other words, the shell layer preferably has structural units derived from monomers containing epoxy groups, i.e., preferably has epoxy groups. When the shell layer of the polymer particles has epoxy groups, the cured product obtained by curing the composition has the advantage of excellent toughness.

[0260] Specific examples of the monomers containing epoxy groups include glycidyl acrylate, 4-hydroxybutyl methacrylate glycidyl ether, allyl glycidyl ether, and other vinyl monomers containing glycidyl groups.

[0261] When the shell of the polymer particles has epoxy groups, the content of the epoxy groups in the shell is preferably more than 0.0 mmol / g and less than 5.0 mmol / g relative to the total mass of the shell of the polymer particles, more preferably more than 0.1 mmol / g and less than 5.0 mmol / g, more preferably more than 0.2 mmol / g and less than 5.0 mmol / g, more preferably more than 0.2 mmol / g and less than 4.0 mmol / g, more preferably more than 0.2 mmol / g and less than 3.0 mmol / g, even more preferably more than 0.2 mmol / g and less than 2.0 mmol / g, and particularly preferably more than 0.3 mmol / g and less than 1.5 mmol / g. According to this scheme, the aggregation of polymer particles is suppressed, thereby allowing the polymer particles to be dispersed in the cured product as primary particles. As a result, the cured product obtained by curing the composition has the advantage of excellent toughness.

[0262] Monomers with epoxy groups are preferably used for the formation of the shell, and more preferably only for the formation of the shell. In other words, the core layer and the intermediate layer preferably do not have epoxy groups.

[0263] From the viewpoint of storage stability of the composition, the shell of the polymer particles preferably does not have epoxy groups.

[0264] Specific examples of monomers having hydroxyl groups that are monomers containing the aforementioned reactive groups include, for example, the aforementioned hydroxyalkyl methacrylates.

[0265] When the shell layer contains structural units derived from polyfunctional monomers having two or more free radical polymerizable double bonds, it tends to prevent polymer particles from swelling in the composition and improves the processability of the composition due to its lower viscosity, and is therefore preferred. On the other hand, from the viewpoint of improving the toughness and impact resistance of the resulting cured product, the shell layer preferably does not contain structural units derived from polyfunctional monomers having two or more free radical polymerizable double bonds.

[0266] Specific examples of the aforementioned multifunctional monomers, excluding conjugated diene monomers such as butadiene, include: allyl methacrylate, allyl alkyl methacrylate, and other allyl alkyl methacrylates; allyl methacrylate; multifunctional (meth)acrylates having two or more (meth)acrylate groups, such as polyethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and tetraethylene glycol di(meth)acrylate; diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene; etc.

[0267] Among these multifunctional monomers, allyl methacrylate and triallyl isocyanurate are preferred.

[0268] The shell is preferably a polymer consisting only of the following structural units: (a) aromatic vinyl units (particularly preferably styrene units) 0% to 50% by mass (preferably 0% to 35% by mass, more preferably 0% to 20% by mass); (b) vinyl cyanide units (particularly preferably acrylonitrile units) 0% to 50% by mass (preferably 0% to 30% by mass, more preferably 0% to 20% by mass); (c) (meth)acrylate units ((i) preferably selected from one or more of methyl acrylate units, butyl acrylate units and methyl methacrylate units, (ii) particularly preferably methyl methacrylate units) 0% to 100% by mass (preferably 5% to 100% by mass, more preferably 70% to 95% by mass); and (d) structural units derived from monomers having epoxy groups (particularly glycidyl methacrylate units) 0% to 50% by mass (preferably 1% to 35% by mass, more preferably 3% to 20% by mass). In this context, (i) the total of aromatic vinyl units, vinyl cyanide units, (meth)acrylate units, and structural units derived from monomers with epoxide groups is 100% by mass, and (ii) 0% by mass means that the structural unit may also be absent.

[0269] The aforementioned monomer components can be used individually or in combination of two or more. The shell may also contain structural units derived from monomers other than those mentioned above.

[0270] The shell can be a single-layer structure or a multi-layer structure. Furthermore, in the case of a multi-layer shell, the polymer components of each layer can also differ within the scope of the foregoing disclosure.

[0271] (B) The component preferably includes at least one polymer particle selected from the following polymer particles (B-1), polymer particles (B-2) and polymer particles (B-3).

[0272] Polymer particles (B-1): The shell of these polymer particles has epoxy groups, and the content of epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell.

[0273] Polymer Particles (B-2): The core layer of these polymer particles is a diene rubber obtained by polymerizing a monomer mixture (monomer mixture for core layer formation) (for example, composed solely of diene rubber obtained by polymerizing this monomer mixture), wherein the monomer mixture contains (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, and the total of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass;

[0274] Polymer Particles (B-3): The core layer of the polymer particles is a diene rubber obtained by polymerizing a monomer mixture (monomer mixture for core layer formation) (for example, composed only of diene rubber obtained by polymerizing the monomer mixture), and the shell layer of the polymer particles has epoxy groups, the content of epoxy groups in the shell layer being 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer, wherein the monomer mixture contains (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, and the total mass of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0275] Polymer particle (B-1) is a polymer particle with a specific shell structure; polymer particle (B-2) is a polymer particle with a specific core structure; and polymer particle (B-3) is a polymer particle with specific structures in both its shell and core. The specific structure of the shell of polymer particle (B-3) is the same as that of the shell of polymer particle (B-1). The specific structure of the core of polymer particle (B-3) is the same as that of the core of polymer particle (B-2). In this specification, polymer particles equivalent to polymer particle (B-3) do not fall within the conceptual scope of polymer particles (B-1) and polymer particles (B-2), and are not equivalent to either polymer particle (B-1) or polymer particle (B-2).

[0276] (B) When the composition contains at least one type of polymer particles selected from polymer particles (B-1), polymer particles (B-2) and polymer particles (B-3), the cured product obtained by curing the composition has the advantage of excellent toughness.

[0277] The core layer of the polymer particles (B-1) preferably contains one or more types selected from diene rubber, (meth)acrylate rubber, and organosiloxane rubber; more preferably, it contains one or more types selected from diene rubber and (meth)acrylate rubber; and even more preferably, it contains diene rubber. According to this scheme, the cured product obtained by curing the composition has the advantage of superior toughness.

[0278] The core layer of the polymer particles (B-1) preferably contains at least 60 parts by mass, more preferably 70 parts by mass, further preferably 80 parts by mass, and particularly preferably 90 parts by mass, selected from diene rubber, (meth)acrylate rubber, and organosiloxane rubber, in a proportion of 100 parts by mass. According to this embodiment, the cured product obtained by curing the composition has the advantage of excellent toughness. The core layer of the polymer particles (B-1) can be selected from at least one type of diene rubber, (meth)acrylate rubber, and organosiloxane rubber, or it can be composed solely of at least one type selected from these.

[0279] Regarding polymer particles (B-2) and polymer particles (B-3), the monomer mixture used to form the core layer (monomer mixture for core layer formation) contains a chain transfer agent. The core layer obtained by polymerizing the monomer mixture for core layer formation containing a chain transfer agent achieves the following advantages: the cured product obtained by curing the composition exhibits excellent toughness.

[0280] There are no particular limitations on the chain transfer agent; any known chain transfer agent may be used. Specific examples of chain transfer agents include tert-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, and 2-ethylhexyl mercaptoacetate.

[0281] Regarding polymer particles (B-2) and polymer particles (B-3), the amount of chain transfer agent in the monomer mixture for core layer formation is preferably 0.01% to 3.00% by mass, more preferably 0.10% to 2.00% by mass, even more preferably 0.20% to 1.00% by mass, further preferably 0.25% to 0.70% by mass, and particularly preferably 0.30% to 0.50% by mass, in 100% by mass of the monomer mixture for core layer formation. According to this scheme, the cured product obtained by curing the composition has the advantage of superior toughness.

[0282] Diene rubber obtained by polymerizing a monomer mixture containing (b1) a conjugated diene monomer, (b2) a vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) a chain transfer agent comprises: structural units derived from the conjugated diene monomer, structural units derived from the vinyl monomer capable of copolymerizing with the conjugated diene monomer, and structural units derived from the decomposition products of the chain transfer agent, in other words, structural units derived from the chain transfer agent. When the polymerization conversion rate is 100%, in the diene rubber obtained by polymerizing a monomer mixture containing (b1) a conjugated diene monomer, (b2) a vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) a chain transfer agent, the content of each structural unit derived from the conjugated diene monomer, the structural unit derived from the vinyl monomer capable of copolymerizing with the conjugated diene monomer, and the structural unit derived from the chain transfer agent can be regarded as being the same as the content of (b1) the conjugated diene monomer, (b2) the vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) the chain transfer agent contained in the monomer mixture. Therefore, the core layer in polymer particles (B-2) and polymer particles (B-3) can also be described as a diene rubber containing (b1') 50.00% to 99.99% by mass of structural units derived from conjugated diene monomers, (b2') 0.00% to 49.99% by mass of structural units derived from vinyl monomers capable of copolymerizing with conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of structural units derived from chain transfer agents.

[0283] The content of polymer particles (B-1) in component (B) is not particularly limited. The content of polymer particles (B-1) in component (B) is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, more preferably 80 parts by mass or more, even more preferably 90 parts by mass or more, and particularly preferably 95 parts by mass or more. The content of polymer particles (B-1) in component (B) can be 100 parts by mass in 100 parts by mass of component (B). In other words, component (B) can consist solely of polymer particles (B-1).

[0284] The content of polymer particles (B-2) in component (B) is not particularly limited. The content of polymer particles (B-2) in component (B) is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, more preferably 80 parts by mass or more, even more preferably 90 parts by mass or more, and particularly preferably 95 parts by mass or more. The content of polymer particles (B-2) in component (B) can be 100 parts by mass in 100 parts by mass of component (B). In other words, component (B) can consist solely of polymer particles (B-2).

[0285] The content of polymer particles (B-3) in component (B) is not particularly limited. The content of polymer particles (B-3) in component (B) is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, more preferably 80 parts by mass or more, even more preferably 90 parts by mass or more, and particularly preferably 95 parts by mass or more. The content of polymer particles (B-3) in component (B) can be 100 parts by mass in 100 parts by mass of component (B). In other words, component (B) can consist solely of polymer particles (B-3).

[0286] Volume average particle size (Mv) of polymer particles

[0287] The volume average particle size (Mv) of the polymer particles is not particularly limited. From the viewpoint of industrial productivity and workability of the curable resin composition, the volume average particle size (Mv) of the polymer particles is preferably 0.01 μm or more and 2.00 μm or less, more preferably 0.03 μm or more and 0.60 μm or less, more preferably 0.05 μm or more and 0.40 μm or less, more preferably 0.10 μm or more and 0.30 μm or less, more preferably 0.15 μm or more and 0.30 μm or less, more preferably 0.16 μm or more and 0.28 μm or less, more preferably 0.17 μm or more and 0.27 μm or less, and even more preferably 0.18 μm or more and 0.25 μm or less. When the volume average particle size (Mv) of the polymer particles is (a) 0.01 μm or more, the viscosity of the composition decreases and the workability is good; when it is (b) 2.00 μm or less, the polymerization time of the polymer particles is shortened and the industrial productivity is improved. The method for determining the volume average particle size (Mv) of polymer particles will be described in detail in the following examples.

[0288] In the composition, the polymer particles, which are component (B), are preferably dispersed in a first-order particle state. In this specification, "polymer particles dispersed in a first-order particle state" (hereinafter also referred to as primary dispersion) means that the polymer particles are dispersed substantially independently of each other (without sticking (adhesion)). The dispersion state of the polymer particles in the composition can be confirmed, for example, by dissolving a portion of the composition in a solvent such as methyl ethyl ketone, and then subjecting the resulting solution to a particle size measuring device using laser scattering, etc., and measuring the particle size of the polymer particles in the solution.

[0289] Furthermore, the term "stable dispersion" of polymer particles refers to a state in which the polymer particles do not aggregate, separate, or precipitate in a continuous layer, and remain stably dispersed under normal conditions for a long period of time. Additionally, preferably, the distribution of polymer particles in the continuous layer remains substantially unchanged, and the "stable dispersion" can be maintained even when the composition is heated to reduce viscosity and stirred within a risk-free range.

[0290] Polymer particles can be used alone or in combination with two or more types.

[0291] Methods for Manufacturing Polymer Particles

[0292] (Methods for manufacturing the core layer)

[0293] The formation of the core layer constituting the polymer particles can be achieved, for example, by emulsion polymerization, suspension polymerization, or micro-suspension polymerization. As for methods such as emulsion polymerization, suspension polymerization, or micro-suspension polymerization, the methods described in International Publication No. 2005 / 028546 or International Publication No. 2006 / 070664 can be appropriately utilized.

[0294] (Methods for forming the shell and intermediate layer)

[0295] If the polymer particles contain an intermediate layer, the intermediate layer can be formed by polymerizing the monomers used to form the intermediate layer using a known free radical polymerization method. If the rubber elastic system constituting the core layer is in the form of an emulsion, then the polymerization of the monomers used to form the intermediate layer is preferably carried out by emulsion polymerization.

[0296] The shell can be formed by polymerizing the shell-forming monomers using a known free radical polymerization method. If the polymer particle precursor having a core layer or a core layer covered by an intermediate layer is formed into an emulsion, then the polymerization of the shell-forming monomers is preferably carried out by emulsion polymerization. As an emulsion polymerization method, for example, the method described in International Publication No. 2005 / 028546 can be appropriately used.

[0297] Emulsifiers (dispersants) can be used in emulsion polymerization.

[0298] Examples of emulsifiers include (i): (i-1) alkyl or aryl sulfonic acids, such as dioctyl sulfosuccinic acid and dodecylbenzene sulfonic acid; alkyl or aryl ether sulfonic acids; alkyl or aryl sulfonic acids, such as dodecyl sulfonic acid; alkyl or aryl ether sulfuric acid; alkyl or aryl substituted phosphoric acid; alkyl or aryl ether substituted phosphoric acid; N-alkyl or aryl sarcosine, such as dodecyl sarcosine; alkyl or aryl carboxylic acids, such as oleic acid and stearic acid; alkyl or aryl ether carboxylic acids; and various acids; and (i-2) anionic emulsifiers (dispersants) such as alkali metal salts or ammonium salts of these acids. Examples also include: (ii) nonionic emulsifiers (dispersants) such as alkyl or aryl substituted polyethylene glycol; and (iii) dispersants such as polyvinyl alcohol, alkyl-substituted cellulose, polyvinylpyrrolidone, and polyacrylic acid derivatives.

[0299] These emulsifiers (dispersants) can be used alone or in combination of two or more.

[0300] To minimize the amount of emulsifier (dispersant) used, provided it does not impair the dispersion stability of the aqueous latex of the polymer particles, it is preferable to reduce the amount of emulsifier (dispersant). Furthermore, higher water solubility of the emulsifier (dispersant) is preferred. Higher water solubility facilitates the removal of the emulsifier (dispersant) through water washing, easily preventing adverse effects on the final cured product.

[0301] When using emulsion polymerization, peroxides (e.g., organic peroxides), chain transfer agents, and surfactants can be used as needed.

[0302] The polymerization temperature, pressure, deoxidation, and other conditions during polymerization can be within a known range.

[0303] The composition preferably contains at least polymer particles as component (B), so that the cured product obtained by curing the composition achieves an excellent balance between improving toughness and impact resistance.

[0304] The content of component (B) in the composition is 1 to 100 parts by weight relative to 100 parts by weight of component (A), preferably 3 to 90 parts by weight, more preferably 5 to 80 parts by weight, even more preferably 10 to 75 parts by weight, and particularly preferably 15 to 70 parts by weight. According to this scheme, the cured product obtained by curing the composition exhibits a superior balance between toughness improvement and impact resistance.

[0305] <1-1-4. (C) Ingredients>

[0306] Component (C) is an acid anhydride (C1), an aromatic amine (C2), or an alicyclic amine (C3). In the composition, component (C) functions as a curing agent. In other words, the composition contains an acid anhydride (C1), an aromatic amine (C2), or an alicyclic amine (C3) as a curing agent.

[0307] Acid anhydrides (C1)

[0308] The following describes the case where component (C) is an acid anhydride (C1) (hereinafter also referred to as Case B). In Case B, the resulting composition has a lower viscosity and a longer shelf life. As a result, the composition exhibits excellent processability in Case B. Furthermore, Case B offers the following advantages: by adding a curing accelerator, the composition cures even at relatively low temperatures; the resulting cured product has a good balance in terms of electrical, chemical, and mechanical properties; and the heat generated during curing is low, making it easier to manufacture large molded articles.

[0309] When component (C) is an acid anhydride (c1), component (C) preferably does not contain aromatic amines (c2) and alicyclic amines (c3), and more preferably consists only of acid anhydride (c1).

[0310] The acid anhydride (C1) is not particularly limited. Examples of acid anhydrides (C1) include, for instance, substituted or unsubstituted compounds such as: 4-methylcyclohexane-1,2-dicarboxylic anhydride, polysaccharide polyanhydride, polyazelite polyanhydride, succinic anhydride, citraconic anhydride, itaconic anhydride, alkenyl-substituted succinic anhydride, octenyl succinic anhydride, dodecenyl succinic anhydride, maleic anhydride, triamic anhydride, norbornene dicarboxylic anhydride, methyl norbornene dicarboxylic anhydride, hydrogenated methyl norbornene dicarboxylic anhydride, and maleic anhydride. Addition linoleic acid, alkyl-terminated alkylene tetrahydrophthalic anhydride, methyl tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyl hexahydrophthalic anhydride, trialkyl tetrahydrophthalic anhydride, pyromellitic dianhydride, trimellitic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, dichloromaleic anhydride, chloronorbornene dicarboxylic anhydride, chloramphenicol anhydride, maleic anhydride grafted polybutadiene, etc.

[0311] Regarding the acid anhydride (c1), preferably (i) it comprises one or more selected from substituted or unsubstituted methylnorbornene carboxylic anhydride, substituted or unsubstituted hydrogenated methylnorbornene carboxylic anhydride, substituted or unsubstituted methyltetrahydrophthalic anhydride, and substituted or unsubstituted methylhexahydrophthalic anhydride, or is composed solely of one or more selected from these; more preferably (ii) it comprises one or more selected from substituted or unsubstituted methylnorbornene carboxylic anhydride, substituted or unsubstituted methyltetrahydrophthalic anhydride, and substituted... The composition may contain one or more of substituted or unsubstituted methylhexahydrophthalic anhydrides, or may consist only of one or more selected from these; more preferably (iii) it contains one or more of substituted or unsubstituted methyltetrahydrophthalic anhydrides, or may consist only of one or more selected from these; particularly preferably (iv) it contains substituted or unsubstituted methyltetrahydrophthalic anhydrides, or may consist only of substituted or unsubstituted methyltetrahydrophthalic anhydrides. According to this scheme, the resulting composition has a low viscosity, thus exhibiting good impregnation with respect to fibers. As a result, it has the advantage of obtaining a cured product with superior toughness. The substituents mentioned above are not particularly limited, and examples include hydrocarbon groups and alkoxy groups.

[0312] In addition, the anhydride (c1) preferably comprises 4-methylcyclohexane-1,2-dicarboxylic anhydride or consists only of 4-methylcyclohexane-1,2-dicarboxylic anhydride, thus having the advantages of particularly low viscosity of the resulting composition and excellent heat resistance of the cured product obtained by curing the composition.

[0313] Aromatic amines (C2)

[0314] When component (C) is an aromatic amine (C2), the cured product obtained by curing the composition has the advantages of excellent heat resistance and high strength and / or toughness.

[0315] When component (C) is an aromatic amine (c2), component (C) preferably does not contain acid anhydride (c1) and alicyclic amine (c3), and more preferably consists only of aromatic amine (c2).

[0316] Aromatic amines (C2) are not particularly limited. Examples of aromatic amines (C2) include: 3,3'-dichloro-4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, trimethylene-bis(4-aminobenzoate), 2,4-diamino-3,5-diethyltoluene, 2,6-diamino-3,5-diethyltoluene, dimethylthiotoluenediamine, diaminodiphenylmethane, diethyltoluenediamine, 4,4'-methylenebis[N-(1-methylpropyl)aniline], 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, 1,3-bis(3-aminophenoxy)benzene, aminobenzylamine, m-phenylenediamine, etc.

[0317] Regarding the aromatic amine (c2), preferably (i) it comprises one or more selected from diethyltoluenediamine, m-phenylenediamine, diaminodiphenylmethane, 2,4-diamino-3,5-diethyltoluene, 2,6-diamino-3,5-diethyltoluene, 3,3'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfone, or is composed only of one or more selected from these; more preferably (ii) it comprises one or more selected from diethyltoluenediamine, m-phenylenediamine, diaminodiphenylmethane, 3,3'-diaminodiphenyl sulfone, and 4,4'-diaminodiphenyl sulfone, or is composed only of one or more selected from these; further preferably (iii) it comprises one or more selected from diethyltoluenediamine, diaminodiphenylmethane, and 4,4'-diaminodiphenyl sulfone, or is composed only of one or more selected from these; particularly preferably (iv) it comprises diethyltoluenediamine, or is composed only of diethyltoluenediamine. According to this scheme, the following advantages are available: the composition has a relatively low viscosity and excellent processability, and the cured product obtained by curing the composition has excellent toughness.

[0318] Alicyclic amines (C3)

[0319] The case where an alicyclic amine (C3) is used as a curing agent, or in other words, when component (C) is an alicyclic amine (C3), will be explained. In this case, the composition cures rapidly, curing proceeds even at relatively low temperatures, and / or curing is completed in a relatively short time. Therefore, when component (C) is an alicyclic amine (C3), it has the advantages of a short curing cycle and excellent productivity. Alicyclic amines (C3) are curing agents that achieve rapid curing. Furthermore, the cured product obtained from a composition containing an alicyclic amine (C3) as component (C) has the advantages of superior heat resistance and high strength and / or toughness.

[0320] When component (C) is an alicyclic amine (C3), component (C) preferably does not contain acid anhydride (C1) and aromatic amine (C2), and more preferably consists only of alicyclic amine (C3).

[0321] Alicyclic amines (C3) are not particularly limited. Examples of alicyclic amines (C3) include isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), aminoethylpiperazine, piperazine, and benzophenyldiamine.

[0322] Regarding the alicyclic amine (c3), preferably (i) it comprises one or more selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), aminoethylpiperazine, piperazine, and phenylenediamine; more preferably, it is composed of only one or more selected from these; more preferably (ii) it comprises one or more selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), and phenylenediamine. (2-methylcyclohexylamine), aminoethylpiperazine, or more preferably, composed of only one or more selected from these; further preferably (iii) comprising one or more selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), or more preferably, composed of only one or more selected from these; particularly preferably (iv) comprising one or more selected from isophorone diamine, 4,4'-methylenebis(cyclohexylamine), or more preferably, composed of only one or more selected from these. According to this scheme, it has the following advantages: (i) the composition has low viscosity and excellent processability; (ii) the composition has fast curing speed and excellent productivity of the cured product; and (iii) the cured product obtained by curing this composition has excellent toughness.

[0323] The content of component (C) in the composition is 5 to 200 parts by mass relative to 100 parts by mass of component (A), preferably 10 to 200 parts by mass, more preferably 11 to 170 parts by mass, more preferably 12 to 150 parts by mass, even more preferably 13 to 130 parts by mass, and particularly preferably 15 to 115 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0324] The following description addresses the case where component (C) is an acid anhydride (Cl). In this case, the content of component (C) in the composition relative to 100 parts by mass of component (A) is preferably 40 to 200 parts by mass, more preferably 50 to 170 parts by mass, even more preferably 55 to 150 parts by mass, further preferably 60 to 130 parts by mass, and particularly preferably 65 to 115 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0325] The following description pertains to the case where component (C) is an acid anhydride (c1). In this case, the content of component (C) in the composition is preferably appropriately set relative to the molar amount of epoxy groups in component (A) contained in the composition. In other words, when component (C) is an acid anhydride (c1), the ratio of the molar amount of anhydride groups in component (C) to the molar amount of epoxy groups in component (A) contained in the composition (molar amount of anhydride groups in component (C) / molar amount of epoxy groups in component (A)) is preferably within a specific range. When component (C) is an acid anhydride (c1), this ratio (molar amount of anhydride groups in component (C) / molar amount of epoxy groups in component (A)) is preferably 0.35 to 0.87, more preferably 0.40 to 0.87, even more preferably 0.45 to 0.87, and particularly preferably 0.50 to 0.87. When component (C) is an anhydride (c1) and the ratio (molar amount of anhydride groups in component (C) / molar amount of epoxy groups in component (A)) is 0.87 or less, the composition tends to have a value of X of 1.05 to 5.50. As a result, the obtained composition has the advantage of being able to provide cured products with superior toughness. When component (C) is an anhydride (c1) and the ratio (molar amount of anhydride groups in component (C) / molar amount of epoxy groups in component (A)) is 0.35 or more, the composition has the advantage of being able to provide cured products with excellent heat resistance, i.e., cured products with high Tg.

[0326] The following description addresses the case where component (C) is an aromatic amine (C2). In this case, the content of component (C) in the composition is 10 to 70 parts by mass relative to 100 parts by mass of component (A), preferably 11 to 60 parts by mass, more preferably 12 to 50 parts by mass, even more preferably 13 to 45 parts by mass, and particularly preferably 15 to 40 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0327] The following description pertains to the case where component (C) is an aromatic amine (C2). In this case, the content of component (C) in the composition is preferably appropriately set relative to the molar amount of epoxy groups in component (A) contained in the composition. In other words, when component (C) is an aromatic amine (C2), the ratio of the molar amount of active hydrogen in the amine in component (C) to the molar amount of epoxy groups in component (A) contained in the composition (molar amount of active hydrogen in amine in component (C) / molar amount of epoxy groups in component (A)) is preferably within a specific range. When component (C) is an aromatic amine (C2), this ratio (molar amount of active hydrogen in amine in component (C) / molar amount of epoxy groups in component (A)) is preferably 0.67 to 0.87, more preferably 0.67 to 0.85, even more preferably 0.67 to 0.83, and particularly preferably 0.68 to 0.82. Alternatively, when component (C) is an aromatic amine (C2), the ratio (molar amount of active hydrogen in the amine in component (C) / molar amount of epoxy groups in component (A)) is preferably 1.10 to 2.40, more preferably 1.25 to 2.30, even more preferably 1.45 to 2.20, further preferably 1.55 to 2.15, and particularly preferably 1.85 to 2.10. According to this scheme, it has the advantage that the value X of the composition tends to be between 1.30 and 9.00. As a result, the obtained composition has the advantage of being able to provide cured products with superior toughness. Furthermore, according to this scheme, the composition also has the advantage of being able to provide cured products with excellent heat resistance, i.e., cured products with high Tg.

[0328] The following description addresses the case where component (C) is an alicyclic amine (C3). In this case, the content of component (C) in the composition relative to 100 parts by mass of component (A) is preferably 5 to 200 parts by mass, more preferably 5 to 70 parts by mass, even more preferably 7 to 60 parts by mass, even more preferably 9 to 50 parts by mass, even more preferably 11 to 45 parts by mass, further preferably 13 to 40 parts by mass, and particularly preferably 15 to 35 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0329] The following description pertains to the case where component (C) is an alicyclic amine (C3). In this case, the content of component (C) in the composition is preferably appropriately set relative to the molar amount of epoxy groups in component (A) contained in the composition. In other words, when component (C) is an alicyclic amine (C3), the ratio of the molar amount of active hydrogen in the amine in component (C) to the molar amount of epoxy groups in component (A) contained in the composition (molar amount of active hydrogen in amine in component (C) / molar amount of epoxy groups in component (A)) is preferably within a specific range. When component (C) is an alicyclic amine (C3), the ratio (molar amount of active hydrogen in amine in component (C) / molar amount of epoxy groups in component (A)) is preferably 0.67 to 0.87, more preferably 0.67 to 0.85, even more preferably 0.67 to 0.83, and particularly preferably 0.68 to 0.82. Alternatively, when component (C) is an alicyclic amine (C3), the ratio (molar amount of active hydrogen in the amine in component (C) / molar amount of epoxy groups in component (A)) is preferably 1.10 to 2.40, more preferably 1.25 to 2.30, even more preferably 1.45 to 2.20, further preferably 1.55 to 2.15, and particularly preferably 1.85 to 2.10. According to this scheme, it has the advantage that the value X of the composition tends to be between 1.30 and 9.00. As a result, the obtained composition has the advantage of being able to provide cured products with superior toughness. Furthermore, according to this scheme, the composition also has the advantage of being able to provide cured products with excellent heat resistance, i.e., cured products with high Tg.

[0330] <1-1-5. (D) Component>

[0331] (D) Component is a curing accelerator. In this specification, "curing accelerator" refers to a substance capable of promoting the curing of the composition. The curing accelerator functions as a catalyst to promote reactions such as the reaction between the epoxy groups contained in component (A), or the reaction between the epoxy groups contained in component (A) and the epoxy groups contained in component (C) or other components.

[0332] (D) Component is not specifically limited. Examples of components (D) include: (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), and 1,1-dimethylphenylurea (trade name: Dyhard); (b) benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 2-(dimethylaminomethyl)phenol, (c) Tertiary amines such as poly(p-vinylphenol) matrix blends with 2,4,6-tris(dimethylaminomethyl)phenol, triethylenediamine, and N,N-dimethylpiperazine; (d) Imidazoles with 1 to 12 carbon atoms (C1-C12), such as N-arylimidazolium, 2-methylimidazolium, 1,2-dimethylimidazolium, 2-ethyl-4-methylimidazolium, N-butylimidazolium, 2-undecylimidazolium, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-undecylimidazolium trimellitate, and addition products of epoxy resins and imidazolium; (e) Lewis acid amine complexes such as boron trifluoride amine complexes and boron trichloride amine complexes; (d) 6-caprolactam, etc. (D) The components can be encapsulated in microcapsules, etc., or can act as potential catalysts that are activated only upon heating. As component (D), a potential curing accelerator can also be used, which is formed by encapsulating imidazoles or tertiary amines in microcapsules. Commercially available products can also be used as such potential curing accelerators (e.g., NOVACURE HX-3722, NOVACURE HX-3742, NOVACURE HX-3088, etc., manufactured by Asahi Kasei Corporation). One of these accelerators can be used alone, or two or more can be used in combination as component (D).

[0333] In the above examples, component (D) preferably (i) contains one or more tertiary amines selected from (b) 2,4,6-tris(dimethylaminomethyl)phenol, triethylenediamine, N,N-dimethylpiperazine, etc., and (c) 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole, etc., more preferably composed of only one or more selected from these; further preferably (ii) contains one or more selected from 2,4,6-tris(dimethylaminomethyl)phenol and 2-ethyl-4-methylimidazole, particularly preferably composed of only one or more selected from these.

[0334] When component (C) is an acid anhydride (c1), the composition preferably contains component (D). When component (C) is an aromatic amine (c2) or an alicyclic amine (c3), the composition may or may not contain component (D).

[0335] When the composition contains component (D), the content of component (D) in the composition is 0.1 to 20.0 parts by weight relative to 100 parts by weight of component (A), preferably 0.2 to 16.0 parts by weight, more preferably 0.5 to 13.0 parts by weight, even more preferably 1.0 to 10.0 parts by weight, and particularly preferably 2.0 to 8.0 parts by weight. According to this scheme, it has the advantage of sufficiently promoting the curing of the composition.

[0336] <1-1-6. Other Added Components>

[0337] The composition may also include other components as needed. Other components are not particularly limited, but examples include: reinforcing agents such as unmodified epoxy rubber polymers, inorganic fillers such as silica and / or silicates, calcium oxide, free radical curing resins, photopolymerization initiators, expanding agents such as azo chemical foaming agents and / or thermally expanding microspheres, colorants such as pigments and / or dyes, extender pigments, ultraviolet absorbers, antioxidants, stabilizers (anti-gelling agents), plasticizers, leveling agents, defoamers, silane coupling agents, antistatic agents, flame retardants, lubricants, tack reducers, low shrinkage agents, organic fillers, thermoplastic resins, desiccants, dispersants, etc.

[0338] <1-1-7. Value X>

[0339] The value X of the composition varies depending on component (C). When component (C) is an acid anhydride (C1), the value X is 1.05 to 5.50. This composition can be used to provide a cured product with excellent toughness. From the viewpoint of further improving the toughness of the cured product, when component (C) is an acid anhydride (C1), the value of X is preferably 1.05 to 5.00, more preferably 1.05 to 4.50, even more preferably 1.06 to 4.25, and particularly preferably 1.07 to 4.00.

[0340] When component (C) is an aromatic amine (C2) or an alicyclic amine (C3), the value of X is 1.30 to 9.00. This formulation allows the composition to provide a cured product with excellent toughness. From the viewpoint of further improving the toughness of the cured product, when component (C) is an aromatic amine (C2) or an alicyclic amine (C3), the value of X is preferably 1.35 to 8.75, more preferably 1.40 to 8.50, even more preferably 1.45 to 8.25, and particularly preferably 1.50 to 8.00.

[0341] The value X of the composition can be adjusted by changing various parameters such as: (i) the molar amount of anhydride groups in component (C) relative to the molar amount of epoxy groups in component (A) contained in the composition (molar amount of anhydride groups in component (C) / molar amount of epoxy groups in component (A)); (ii) the molar amount of active hydrogen in amines in component (C) relative to the molar amount of epoxy groups in component (A) contained in the composition (molar amount of active hydrogen in amines in component (C) / molar amount of epoxy groups in component (A)); (iii) the average epoxy equivalent of the epoxy-containing substance (A) contained in the composition; (iv) the average anhydride equivalent of the anhydride (c1) contained in the composition, the average active hydrogen equivalent of the amine of the aromatic amine (c2) contained in the composition, or the average active hydrogen equivalent of the amine of the alicyclic amine (c3) contained in the composition. The composition contains: (v) the amount of polyfunctional epoxy group-containing substance (a1) with an epoxy equivalent of 300 g / eq or more but less than 3000 g / eq and having 2 or more epoxy groups per molecule; (vi) the amount of monofunctional epoxy group-containing substance (a2) with 1 epoxy group per molecule; (vii) the average number of epoxy groups per molecule of epoxy group-containing substance (A) contained in the composition; (viii) the average number of anhydride groups per molecule of acid anhydride (c1) contained in the composition, the average number of active hydrogen groups of amine per molecule of aromatic amine (c2) contained in the composition, or the average number of active hydrogen groups of amine per molecule of alicyclic amine (c3) contained in the composition; and (ix) the type and amount of curing accelerator (D) contained in the composition.

[0342] In the calculation of value X, the curing conditions of composition (M) when curing composition (M) to obtain cured product (M) (e.g., curing temperature, curing time, thickness of composition before curing, etc.) are the same as the curing conditions of composition (Meq) when curing composition (Meq) to obtain cured product (Meq).

[0343] <1-1-8. Value Y>

[0344] The value Y of the composition reflects the molecular weight between the crosslinking points of the composition. The preferred value Y is 22–400, more preferably 25–360, even more preferably 30–320, further preferably 35–280, and particularly preferably 40–200. A higher value Y results in a cured product with superior elongation properties. A lower value Y results in a cured product with superior strength and heat resistance.

[0345] The value Y of the composition can be adjusted by changing various parameters such as: (i) the average epoxy equivalent of the epoxy-containing substance (A) contained in the composition; (ii) the average acid anhydride equivalent of the acid anhydride (c1) contained in the composition, the average active hydrogen equivalent of the amine of the aromatic amine (c2) contained in the composition, or the average active hydrogen equivalent of the amine of the alicyclic amine (c3) contained in the composition; (iii) the content of the polyfunctional epoxy-containing substance (a1) in the composition having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups per molecule; (iv) the monofunctional epoxy-containing substance (a2) having 1 epoxy group per molecule. The content of the composition; (v) the average number of epoxy groups per molecule of the epoxy-containing substance (A) contained in the composition; (vi) the average number of anhydride groups per molecule of the acid anhydride (c1) contained in the composition, the average number of active hydrogen atoms of the amine per molecule of the aromatic amine (c2) contained in the composition, or the average number of active hydrogen atoms of the amine per molecule of the alicyclic amine (c3) contained in the composition; (vii) the type and amount of the curing accelerator (D) contained in the composition; and (viii) the amount of the acid anhydride (c1) contained in the composition, the amount of the aromatic amine (c2) contained in the composition, or the amount of the alicyclic amine (c3) contained in the composition.

[0346] <1-1-9. Viscosity of Curing Resin Compositions>

[0347] From the viewpoint of achieving excellent impregnation with respect to fibers, the viscosity of the composition at 25°C is preferably 5000 mPa·s or less, more preferably 4000 mPa·s or less, more preferably 3000 mPa·s or less, more preferably 2500 mPa·s or less, more preferably 2000 mPa·s or less, even more preferably 1000 mPa·s or less, and particularly preferably 800 mPa·s or less. Similarly, from the viewpoint of achieving excellent impregnation with respect to fibers, the viscosity of the composition at 50°C is preferably 1000 mPa·s or less, more preferably 800 mPa·s or less, even more preferably 500 mPa·s or less, even more preferably 300 mPa·s or less, and particularly preferably 200 mPa·s or less.

[0348] The composition can also be used within a range where a balance is achieved between sufficient viscosity reduction (preferably below 200 mPa·s) and sufficient working time before curing, for example, after heating to a temperature of 40°C to 100°C, preferably 40°C to 90°C, and more preferably 50°C to 80°C.

[0349] [1-2. A curable resin composition that at least satisfies the aforementioned condition (2)]

[0350] The following section describes curable resin compositions that at least satisfy the aforementioned condition (2).

[0351] <1-2-1. Technical concept of a curable resin composition that at least satisfies the aforementioned matter (2)>

[0352] In terms of toughness, there is still room for improvement in previously known curable resin compositions. Therefore, the inventors have conducted in-depth research with the aim of providing novel curable resin compositions that offer excellent toughness.

[0353] In curable resin compositions containing epoxy-containing substances (such as epoxy resins), the more epoxy groups per molecule of the epoxy-containing substance, the higher the crosslinking density of the cured product. Furthermore, comparing substances with the same number of epoxy groups per molecule, the smaller the molecular weight of the epoxy-containing substance, the higher the crosslinking density of the cured product; conversely, the larger the molecular weight of the epoxy-containing substance, the lower the crosslinking density of the cured product. A higher crosslinking density of the cured product indicates a smaller molecular weight between crosslinking points. For example, in a curable resin composition containing a large amount of a polyfunctional epoxy-containing substance, a high crosslinking density can be interpreted as a smaller molecular weight between crosslinking points.

[0354] Through in-depth research, the inventors have independently obtained the following new insights: by controlling the molecular weight between the crosslinking points of the cured material within a specific range and using polymer particles, the toughness of the cured material is surprisingly excellent.

[0355] The molecular weight between the crosslinking points of the cured material can be calculated based on the theory of rubber elasticity of crosslinked rubber, according to, for example, the following formula:

[0356] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × T / E = ρ × R × T / G

[0357] In the formula, μ represents the Poisson's ratio of the cured product, ρ represents the specific gravity of the cured product, R represents the gas constant, T represents the absolute temperature (K), and E and G represent the Young's modulus and rigidity modulus of the cured product in the rubbery domain. The rubbery domain refers to the region further towards the higher temperature side of the transition region near the glass transition temperature obtained when measuring the temperature dependence of elastic modulus (Young's modulus, rigidity modulus, etc.), representing a region where the temperature dependence of elastic modulus is relatively flat. Crosslinked polymers such as epoxy resin cured products do not have a flow domain further towards the higher temperature side than the rubbery domain; therefore, E and G in the formula can be represented by the minimum values ​​of the Young's modulus and rigidity modulus of the rubbery domain. Furthermore, the Young's modulus of the rubbery domain is approximately equal to the storage modulus under the easily measured dynamic viscoelasticity, therefore the molecular weight between the crosslinking points can be calculated using the following formula.

[0358] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × (273 + Tmin) / E'min

[0359] In the formula, μ represents the Poisson's ratio of the cured material, ρ represents the specific gravity of the cured material, R represents the gas constant, E'min represents the minimum value of the storage elastic modulus of the cured material, and Tmin represents the temperature (°C) at which the storage elastic modulus of the cured material reaches its minimum value.

[0360] The molecular weight between crosslinking points of the cured product (α) formed by curing a curable resin composition (α) containing an epoxy group-containing substance ((A) component), polymer particles ((B) component), a curing agent ((C) component), and a curing accelerator ((D) component) can be expressed by the following formula:

[0361] The molecular weight between the crosslinking points of the cured product (α) = {2×[1+μ(cured product (α))]×ρ(cured product (α))×R×[273+Tmin(cured product (α))] / E'min(cured product (α))}.

[0362] Here, the Poisson's ratio (μ) and specific gravity (ρ) of the cured product depend on the type of resin component (A) in the curable resin composition, but are almost unaffected by the type and amount of epoxy-containing substances as long as component (A) is an epoxy-containing substance. Therefore, in cured products containing epoxy-containing substances, the Poisson's ratio (μ) and specific gravity (ρ) of the cured product can be considered as "constants". Furthermore, R is a constant (gas constant). Therefore, if the formula only represents the variable portion of the molecular weight between the crosslinking points of the cured product (α), it is as follows:

[0363] The variable portion of molecular weight between crosslinking points of the cured product (α) = [273 + Tmin(M)] / [E'(M)]

[0364] In this specification, the variable portion of the molecular weight between crosslinking points of the cured product (α) is referred to as the value Y. That is, the inventors conducted in-depth research and discovered a novel insight that by controlling the value Y within a specified range and using polymer particles, the toughness of the cured product becomes surprisingly excellent, thus completing this invention.

[0365] It should be noted that the evaluation of the molecular weight between crosslinking points should be based on the measured value of the cured product formed by curing a composition containing only components (A), (C), and (D). This is because components (A) and (C) are used to form the crosslinking structure, and component (D) can affect the progress of the crosslinking reaction. Conversely, when evaluating the molecular weight between crosslinking points, components (B) and components other than (A) to (D) (e.g., inorganic fillers) should not be added. This is because, although these components do not participate in the formation of crosslinks, they can affect the E'min and other parameters of the cured product formed by curing the composition, thus making it impossible to correctly evaluate the molecular weight between crosslinking points. It should also be noted that component (D) is not incorporated into the crosslinking structure. Since it is a curing accelerator and its added amount is relatively small compared to the total amount of components (A) and (C), it is considered that the unreacted (D) component remaining after curing has a relatively small impact on the molecular weight between crosslinking points.

[0366] Conventionally, for reasons such as excellent heat resistance and / or strength of the resulting cured product, excellent workability due to low viscosity of the composition, and excellent cost-effectiveness, curable resin compositions containing epoxy-containing substances generally use a large amount of multifunctional epoxy-containing substances with low epoxy equivalents as the epoxy-containing material. Even when monofunctional epoxy-containing substances and epoxy-containing substances with high epoxy equivalents are used occasionally, their combined amount is negligible (less than 5 parts by mass per 100 parts by mass of the epoxy-containing material). However, the inventors have, for the first time, focused on using previously rarely used monofunctional epoxy-containing substances and / or epoxy-containing substances with high epoxy equivalents, setting their amounts to a certain level or higher, controlling the molecular weight values ​​between the corresponding crosslinking points within a specified range, and further using polymer particles, thereby solving the above-mentioned problems and completing the present invention. It should be noted that previous understanding involved dispersing polymer particles (B) within component (A) (e.g., epoxy resin) to induce large-scale plastic deformation of the epoxy resin, thereby consuming energy and improving toughness. However, this invention proposes that by controlling the molecular weight between crosslinking points within a specified range in the presence of polymer particles (B), plastic deformation of the cured material becomes easier, thus significantly improving toughness. In other words, this technical concept of controlling the molecular weight between crosslinking points within a specified range is arguably a completely unthinkable concept from existing technologies.

[0367] <1-2-2.(A)Component>

[0368] In the curable resin composition that at least satisfies the aforementioned condition (2), the total content of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin is 5 parts by weight to 100 parts by weight of component (A), preferably 10 parts by weight to 95 parts by weight, more preferably 10 parts by weight to 94 parts by weight, more preferably 15 parts by weight to 93 parts by weight, more preferably 20 parts by weight to 93 parts by weight, more preferably 25 parts by weight to 93 parts by weight, more preferably 30 parts by weight to 93 parts by weight, and even more preferably... The composition is selected as 35 to 93 parts by weight, more preferably 40 to 93 parts by weight, even more preferably 45 to 93 parts by weight, even more preferably 50 to 93 parts by weight, even more preferably 50 to 92 parts by weight, preferably 50 to 90 parts by weight, even more preferably 45 to 85 parts by weight, even more preferably 50 to 85 parts by weight, even more preferably 50 to 80 parts by weight, further preferably 55 to 80 parts by weight, and particularly preferably 60 to 80 parts by weight. According to this scheme, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength, elastic modulus, and heat resistance (high Tg). In the curable resin composition that at least satisfies the foregoing (2), component (A) may not contain other epoxy-containing substances (e.g., glycidylamine type epoxy resin, etc.) described later.

[0369] In a curable resin composition that at least satisfies the aforementioned condition (2), component (A) satisfies any one of the following conditions (i), (ii), or (iii):

[0370] (i) Component A contains a substance (a1) containing a polyfunctional epoxy group, and the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 100 parts by mass per 100 parts by mass of component A.

[0371] (ii) Component A contains a substance (a2) containing a monofunctional epoxy group, and the content of the substance (a2) containing a monofunctional epoxy group is 5 to 95 parts by mass per 100 parts by mass of component A.

[0372] (iii) Component A contains a substance (a1) containing a polyfunctional epoxy group and a substance (a2) containing a monofunctional epoxy group. The content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of component A is 5 parts by mass to 95 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) in 100 parts by mass of component A is 5 parts by mass to 95 parts by mass.

[0373] In a curable resin composition that at least satisfies the aforementioned condition (2), component (A) may: (i) contain a substance containing a polyfunctional epoxy group (a1) and not contain a substance containing a monofunctional epoxy group (a2); (ii) contain a substance containing a monofunctional epoxy group (a2) and not contain a substance containing a polyfunctional epoxy group (a1); (iii) contain both a substance containing a polyfunctional epoxy group (a1) and a substance containing a monofunctional epoxy group (a2). In a curable resin composition that at least satisfies the aforementioned condition (2), if component (A) contains a substance containing a polyfunctional epoxy group (a1), the cured product obtained by curing the composition has the advantage of excellent toughness. On the other hand, in a curable resin composition that at least satisfies the aforementioned condition (2), if component (A) does not contain a substance containing a polyfunctional epoxy group (a1), the composition has the advantage of relatively low viscosity and excellent processability. In a curable resin composition that satisfies at least the aforementioned condition (2), if component (A) contains a substance (a2) containing a monofunctional epoxy group, it has the advantages of low viscosity and excellent processability of the composition, as well as excellent toughness of the cured product obtained by curing the composition. On the other hand, in a curable resin composition that satisfies at least the aforementioned condition (2), if component (A) does not contain a substance (a2) containing a monofunctional epoxy group, it has the advantages of excellent strength and heat resistance (high Tg) of the cured product obtained by curing the composition.

[0374] In a curable resin composition that at least satisfies the aforementioned condition (2), the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by weight of component (A) is preferably 5 to 100 parts by weight, more preferably 7 to 50 parts by weight, even more preferably 10 to 50 parts by weight, even more preferably 10 to 40 parts by weight, further preferably 15 to 40 parts by weight, and particularly preferably 15 to 30 parts by weight. According to this scheme, the following advantages are available: the composition has relatively low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent toughness. In a curable resin composition that at least satisfies the aforementioned condition (2), the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by weight of component (A) can be less than 100 parts by weight.

[0375] In a curable resin composition that at least satisfies the aforementioned condition (2), the content of the monofunctional epoxy group-containing substance (a2) in 100 parts by weight of component (A) is preferably 5 to 95 parts by weight, more preferably 7 to 58 parts by weight, more preferably 8 to 50 parts by weight, more preferably 10 to 50 parts by weight, more preferably 15 to 45 parts by weight, more preferably 15 to 40 parts by weight, even more preferably 15 to 35 parts by weight, and particularly preferably 20 to 30 parts by weight. According to this scheme, it has the following advantages: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition has excellent strength and / or toughness. In a curable resin composition that at least satisfies the aforementioned condition (2), the content of the monofunctional epoxy group-containing substance (a2) in 100 parts by weight of component (A) can be less than 95 parts by weight.

[0376] In a curable resin composition that satisfies at least the aforementioned condition (2), component (A) preferably contains a substance (a1) containing a polyfunctional epoxy group and a substance (a2) containing a monofunctional epoxy group, thus possessing the advantage of superior toughness in the cured product obtained by curing the composition. Hereinafter, the case where component (A) in a curable resin composition that satisfies at least the aforementioned condition (2) contains a substance (a1) containing a polyfunctional epoxy group and a substance (a2) containing a monofunctional epoxy group (hereinafter also referred to as "case C") will be described. In case C, of ​​100 parts by mass of component (A), preferably (i) the content of the substance (a1) containing polyfunctional epoxy groups is 5 parts by mass to 95 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 95 parts by mass; more preferably (ii) the content of the substance (a1) containing polyfunctional epoxy groups is 5 parts by mass to 50 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 5 parts by mass to 50 parts by mass; even more preferably (iii) the content of the substance (a1) containing polyfunctional epoxy groups is 10 parts by mass to 40 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 7 parts by mass to 40 parts by mass; particularly preferably (iv) the content of the substance (a1) containing polyfunctional epoxy groups is 15 parts by mass to 30 parts by mass, and the content of the substance (a2) containing monofunctional epoxy groups is 8 parts by mass to 30 parts by mass. According to this scheme, the following advantages are achieved: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition exhibits excellent strength and / or toughness. In case C, in 100 parts by mass of component (A), (i) the content of the substance containing polyfunctional epoxy groups (a1) may also be less than 95 parts by mass, and / or, (ii) the content of the substance containing monofunctional epoxy groups (a2) may also be less than 95 parts by mass.

[0377] In a curable resin composition that at least satisfies the aforementioned condition (2), the multifunctional epoxy-containing substance (a1) may be one or more epoxy-containing substances selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin, or may be epoxy-containing substances other than bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin. In a curable resin composition that at least satisfies the aforementioned condition (2), the monofunctional epoxy-containing substance (a2) may be an alicyclic epoxy resin, or may be an epoxy-containing substance other than an alicyclic epoxy resin. In other words, in a curable resin composition that at least satisfies the aforementioned condition (2), component (A) may also further contain: epoxy-containing substances other than bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin, i.e., other epoxy-containing substances.

[0378] In a curable resin composition that at least satisfies the aforementioned condition (2), if the composition contains an alicyclic epoxy resin as component (A), then the composition preferably contains an acid anhydride (C1) as component (C).

[0379] In a curable resin composition that at least satisfies the aforementioned matter (2), the specific manner relating to component (A), other than those described above, is the same as that mentioned in the aforementioned <1-1-2.Component (A)> section, therefore, the relevant description is cited and omitted here. The preferred manner relating to component (A), other than those described above, in a curable resin composition that at least satisfies the aforementioned matter (1), is also preferred in a curable resin composition that at least satisfies the aforementioned matter (2).

[0380] <1-2-3. (B) Components>

[0381] The specific manner of component (B) is the same as that described in the aforementioned <1-1-3.(B)Component> section, therefore the relevant description is cited and omitted here. The preferred manner of component (B) in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of component (B) in a curable resin composition that at least satisfies the aforementioned matter (2).

[0382] <1-2-4. (C) Ingredients>

[0383] In a curable resin composition that at least satisfies the aforementioned condition (2), component (C) is an epoxy curing agent. In a curable resin composition that at least satisfies the aforementioned condition (2), the epoxy curing agent as component (C) comprises at least one selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0384] Acid anhydrides (C1)

[0385] The case where component (C) of the curable resin composition that at least satisfies the aforementioned condition (2) contains an anhydride (C1) or is an anhydride (C1) (hereinafter also referred to as "Case D") will be described. In Case D, the resulting composition has a lower viscosity and a longer shelf life. As a result, the composition in Case D has the advantage of excellent processability. In addition, Case D has the following advantages: by adding a curing accelerator, the composition cures even at relatively low temperatures; the resulting cured product has a good balance in terms of electrical, chemical, and mechanical properties; and the heat generated during curing is low, making it easy to produce large molded articles.

[0386] In a curable resin composition that at least satisfies the foregoing (2), when component (C) contains an anhydride (c1), component (C) preferably does not contain aromatic amines (c2) and alicyclic amines (c3), and more preferably consists only of anhydride (c1).

[0387] The specific example of acid anhydride (c1) is the same as that mentioned in the "Acid Anhydride (c1)" section of <1-1-4.(C) Components> above, therefore the relevant record is cited and its description is omitted here. The preferred form of acid anhydride (c1) in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred form of acid anhydride (c1) in a curable resin composition that at least satisfies the aforementioned matter (2).

[0388] Aromatic amines (C2)

[0389] In a curable resin composition that at least satisfies the aforementioned condition (2), if component (C) contains an aromatic amine (c2) or is an aromatic amine (c2), then the cured product obtained by curing the composition has the advantages of excellent heat resistance and high strength and / or toughness.

[0390] In a curable resin composition that at least satisfies the aforementioned condition (2), if component (C) contains an aromatic amine (c2), then component (C) preferably does not contain anhydride (c1) and alicyclic amine (c3), and more preferably consists only of aromatic amine (c2).

[0391] The specific examples of aromatic amines (c2) are the same as those mentioned in the "Aromatic Amines (c2)" section of <1-1-4.(C) Ingredients> above, therefore the relevant description is cited and omitted here. Aromatic amines (c2) are preferred in curable resin compositions that at least satisfy the aforementioned matter (1), and are also preferred in curable resin compositions that at least satisfy the aforementioned matter (2).

[0392] Alicyclic amines (C3)

[0393] In a curable resin composition that at least satisfies the aforementioned condition (2), if component (C) contains an alicyclic amine (C3) or is an alicyclic amine (C3), then the curing speed of the composition is fast, and curing can proceed even at lower temperatures and / or be completed in a shorter time. Therefore, in a curable resin composition that at least satisfies the aforementioned condition (2), if component (C) is an alicyclic amine (C3), it has the advantages of a short curing cycle and excellent productivity. Alicyclic amines (C3) are curing agents that achieve rapid curing. On the other hand, in a curable resin composition that at least satisfies the aforementioned condition (2), the cured product obtained by curing a composition containing an alicyclic amine (C3) as component (C) has the advantages of superior heat resistance and high strength and / or toughness.

[0394] In a curable resin composition that at least satisfies the aforementioned condition (2), if component (C) contains an alicyclic amine (c3), component (C) preferably does not contain anhydride (c1) and aromatic amine (c2), and more preferably consists only of an alicyclic amine (c3).

[0395] The specific examples of alicyclic amines (c3) are the same as those mentioned in the section on "Alicyclic Amines (c3)" in the aforementioned <1-1-4.(C) Ingredients> column, therefore the relevant description is cited and omitted here. The preferred form of alicyclic amine (c3) in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred form of alicyclic amine (c3) in a curable resin composition that at least satisfies the aforementioned matter (2).

[0396] In a curable resin composition that at least satisfies the aforementioned condition (2), the content of component (C) in the composition is 10 to 200 parts by mass relative to 100 parts by mass of component (A), preferably 11 to 170 parts by mass, more preferably 12 to 150 parts by mass, even more preferably 13 to 130 parts by mass, and particularly preferably 15 to 115 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0397] The case where component (C) in a curable resin composition that at least satisfies the aforementioned condition (2) includes or is an acid anhydride (C1) will be described. In this case, the content of component (C) in the composition relative to 100 parts by mass of component (A) is preferably 40 to 200 parts by mass, more preferably 50 to 170 parts by mass, even more preferably 55 to 150 parts by mass, further preferably 60 to 130 parts by mass, and particularly preferably 65 to 115 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0398] The case where component (C) in a curable resin composition that at least satisfies the aforementioned condition (2) contains an aromatic amine (C2) or is an aromatic amine (C2) will be described. In this case, the content of component (C) in the composition is 10 to 70 parts by mass relative to 100 parts by mass of component (A), preferably 11 to 60 parts by mass, more preferably 12 to 50 parts by mass, further preferably 13 to 45 parts by mass, and particularly preferably 15 to 40 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0399] The case where component (C) contains or is an alicyclic amine (C3) will be described. In this case, the content of component (C) in the composition is 5 to 70 parts by mass relative to 100 parts by mass of component (A), preferably 7 to 60 parts by mass, more preferably 9 to 50 parts by mass, even more preferably 11 to 45 parts by mass, further preferably 13 to 40 parts by mass, and particularly preferably 15 to 35 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0400] <1-2-5. (D) Components>

[0401] Regarding the specific manner of component (D), the content mentioned above in the <1-1-5.(D) component> section is the same, therefore the relevant record is cited and its description is omitted here. The preferred manner of component (D) in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of component (D) in a curable resin composition that at least satisfies the aforementioned matter (2).

[0402] <1-2-6. Other Added Components>

[0403] The specific methods for introducing other ingredients are the same as those mentioned in the aforementioned <1-1-6. Other Introduced Ingredients> section, so the relevant records are cited and their explanations are omitted here.

[0404] <1-2-7. Value Y>

[0405] Regarding the specific manner of the value Y, the content mentioned in the aforementioned <1-1-8. Value Y> section is the same, therefore the relevant record is cited and its description is omitted here. The preferred manner of the value Y in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of the value Y in a curable resin composition that at least satisfies the aforementioned matter (2).

[0406] <1-2-8. Viscosity of Curing Resin Compositions>

[0407] Regarding the specific manner of determining the viscosity of the curing resin composition, the same manner was described in the aforementioned section <1-1-9. Viscosity of Curing Resin Composition>, therefore the relevant description is cited but omitted here. The preferred manner of determining the viscosity of the curing resin composition in a curing resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of determining the viscosity of the curing resin composition in a curing resin composition that at least satisfies the aforementioned matter (2).

[0408] [1-3. Curable resin compositions that at least satisfy the aforementioned condition (3)]

[0409] The following section describes curable resin compositions that at least satisfy the aforementioned condition (3).

[0410] <1-3-1. Technical concept of a curable resin composition that at least satisfies the aforementioned matter (3)>

[0411] In terms of toughness, there is still room for improvement in previously known curable resin compositions. Therefore, the inventors have conducted in-depth research with the aim of providing novel curable resin compositions that offer excellent toughness.

[0412] In curable resin compositions containing epoxy-containing substances (e.g., epoxy resins), the more active hydrogen atoms on the amino groups of each epoxy curing agent molecule, the higher the crosslinking density of the cured product. The higher the crosslinking density of the cured product, the smaller the molecular weight between the crosslinking points.

[0413] Through in-depth research, the inventors have independently obtained the following new insights: by controlling the molecular weight between the crosslinking points of the cured material within a specific range and using polymer particles, the toughness of the cured material is surprisingly excellent.

[0414] The molecular weight between the crosslinking points of the cured material can be calculated based on the theory of rubber elasticity of crosslinked rubber, according to, for example, the following formula:

[0415] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × T / E = ρ × R × T / G

[0416] In the formula, μ represents the Poisson's ratio of the cured product, ρ represents the specific gravity of the cured product, R represents the gas constant, T represents the absolute temperature (K), and E and G represent the Young's modulus and rigidity modulus of the cured product in the rubbery domain. The rubbery domain refers to the region further towards the higher temperature side of the transition region near the glass transition temperature obtained when measuring the temperature dependence of elastic modulus (Young's modulus, rigidity modulus, etc.), representing a region where the temperature dependence of elastic modulus is relatively flat. Crosslinked polymers such as epoxy resin cured products do not have a flow domain further towards the higher temperature side than the rubbery domain; therefore, E and G in the formula can be represented by the minimum values ​​of the Young's modulus and rigidity modulus of the rubbery domain. Furthermore, the Young's modulus of the rubbery domain is approximately equal to the storage modulus under the easily measured dynamic viscoelasticity, therefore the molecular weight between the crosslinking points can be calculated using the following formula.

[0417] Molecular weight between cross-linking points = 2 × (1 + μ) × ρ × R × (273 + Tmin) / E'min

[0418] In the formula, μ represents the Poisson's ratio of the cured material, ρ represents the specific gravity of the cured material, R represents the gas constant, E'min represents the minimum value of the storage elastic modulus of the cured material, and Tmin represents the temperature (°C) at which the storage elastic modulus of the cured material reaches its minimum value.

[0419] The molecular weight between crosslinking points of the cured product (α) formed by curing a curable resin composition (α) containing an epoxy group-containing substance ((A) component), polymer particles ((B) component), a curing agent ((C) component), and a curing accelerator ((D) component) can be expressed by the following formula:

[0420] The molecular weight between the crosslinking points of the cured product (α) = {2×[1+μ(cured product (α))]×ρ(cured product (α))×R×[273+Tmin(cured product (α))] / E'min(cured product (α))}.

[0421] Here, the Poisson's ratio (μ) and specific gravity (ρ) of the cured product depend on the type of resin component (A) in the curable resin composition, but are almost unaffected by the type and amount of epoxy-containing substances as long as component (A) is an epoxy-containing substance. Therefore, in cured products containing epoxy-containing substances, the Poisson's ratio (μ) and specific gravity (ρ) of the cured product can be considered as "constants". Furthermore, R is a constant (gas constant). Therefore, if the formula only represents the variable portion of the molecular weight between the crosslinking points of the cured product (α), it is as follows:

[0422] The variable part of molecular weight between crosslinking points of the cured product (α) = [273 + Tmin(M)] / [E'(M)].

[0423] In this specification, the "variable portion of molecular weight between crosslinking points of the cured product (α)" mentioned above is designated as "value Y". That is, the inventors conducted in-depth research and discovered a new insight that by controlling value Y within a specified range and using polymer particles, the toughness of the cured product is surprisingly excellent, thus completing this invention.

[0424] It should be noted that the evaluation of the molecular weight between crosslinking points should be based on the measured value of the cured product formed by curing the composition containing only components (A), (C), and (D). This is because components (A) and (C) are used to form the crosslinking structure, and component (D) can affect the progress of the crosslinking reaction. Conversely, when evaluating the molecular weight between crosslinking points, component (B) and components other than (A), (C), and (D) (e.g., inorganic fillers) cannot be added. This is because, although these components do not participate in the formation of crosslinks, they can affect the E'min and other parameters of the cured product formed by curing the composition, thus preventing a proper evaluation of the molecular weight between crosslinking points. It should also be noted that component (D) is not incorporated into the crosslinking structure. Because it is a curing accelerator, its added amount is relatively small compared to the total amount of components (A) and (C). Therefore, it is believed that the unreacted (D) component remaining after curing has a relatively small impact on the molecular weight between crosslinking points.

[0425] Conventionally, from the viewpoint of achieving rapid curing of the composition and the strength of the resulting cured product, epoxy curing agents with a high number of active hydrogen atoms (e.g., 4 or more) on the amino groups per molecule are generally used as epoxy curing agents in curable resin compositions. Even when epoxy curing agents with a low number of active hydrogen atoms on the amino groups per molecule are used, they are usually used together with epoxy curing agents with a high number of active hydrogen atoms on the amino groups per molecule, and the epoxy curing agents as a whole have a relatively high number of active hydrogen atoms on the amino groups per molecule. However, the inventors have for the first time focused on using a large amount of epoxy curing agents with a low number of active hydrogen atoms on the amino groups per molecule, which were almost never used before, thereby controlling the molecular weight value between the crosslinking points within a specified range, and further using polymer particles, thereby solving the above-mentioned problems and completing the present invention. It should be noted that the conventional understanding is to disperse polymer particles (B) in component (A) (e.g., epoxy resin) to induce large-scale plastic deformation of the epoxy resin to consume energy and thus improve toughness. This invention proposes that by controlling the molecular weight between crosslinking points within a specified range in the presence of polymer particles (B), the plastic deformation of the cured material becomes easier, thereby significantly improving its toughness. In other words, this technical concept of controlling the molecular weight between crosslinking points within a specified range is arguably a completely unthinkable concept from existing technologies.

[0426] <1-3-2.(A)Component>

[0427] In a curable resin composition that at least satisfies the aforementioned condition (3), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin is 5 parts by weight to 100 parts by weight, preferably 10 parts by weight to 100 parts by weight, more preferably 20 parts by weight to 100 parts by weight, more preferably 30 parts by weight to 100 parts by weight, more preferably 40 parts by weight to 100 parts by weight, more preferably 50 parts by weight to 100 parts by weight, more preferably 60 parts by weight to 100 parts by weight, more preferably 70 parts by weight to 100 parts by weight, more preferably 80 parts by weight to 100 parts by weight, further preferably 90 parts by weight to 100 parts by weight, and particularly preferably 95 parts by weight to 100 parts by weight. In a curable resin composition that at least satisfies the aforementioned condition (3), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin may be less than 100 parts by weight in 100 parts by weight of component (A). According to this scheme, the following advantages are achieved: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition exhibits excellent strength, elastic modulus, and heat resistance (high Tg). In the curable resin composition that at least satisfies the aforementioned matter (3), the total content of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin may also be 100 parts by mass of component (A). In other words, in the curable resin composition that at least satisfies the aforementioned matter (3), component (A) may consist only of bisphenol A type epoxy resin, or only of bisphenol F type epoxy resin, or only of alicyclic epoxy resin, or only of bisphenol A type epoxy resin and alicyclic epoxy resin, or only of bisphenol F type epoxy resin and alicyclic epoxy resin, or only of bisphenol A type epoxy resin and bisphenol F type epoxy resin, or only of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alicyclic epoxy resin. In a curable resin composition that at least satisfies the foregoing condition (3), component (A) may not contain other epoxy-containing substances described below (e.g., glycidyl amine type epoxy resin, etc.).

[0428] In a curable resin composition that satisfies at least the aforementioned condition (3), component (A) preferably contains a substance (a1) containing a polyfunctional epoxy group and a substance (a2) containing a monofunctional epoxy group, so that the cured product obtained by curing the composition has the advantage of superior toughness. Hereinafter, the case (hereinafter also referred to as "case E") in which component (A) of a curable resin composition that satisfies at least the aforementioned condition (3) contains a substance (a1) containing a polyfunctional epoxy group and a substance (a2) containing a monofunctional epoxy group will be described. In case E, of 100 parts by mass of component (A), preferably (i) the content of the polyfunctional epoxy group-containing substance (a1) is 5 parts by mass to 95 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 5 parts by mass to 95 parts by mass; more preferably (ii) the content of the polyfunctional epoxy group-containing substance (a1) is 6 parts by mass to 50 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 6 parts by mass to 50 parts by mass; more preferably (iii) the content of the polyfunctional epoxy group-containing substance (a1) is 7 parts by mass to 40 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 7 parts by mass to 40 parts by mass; more preferably (iv) the content of the polyfunctional epoxy group-containing substance (a1) is 7 parts by mass to 35 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 7 parts by mass. ~35 parts by mass; more preferably (v) the content of the polyfunctional epoxy group-containing substance (a1) is 8 parts by mass to 33 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 7 parts by mass to 33 parts by mass; more preferably (vi) the content of the polyfunctional epoxy group-containing substance (a1) is 9 parts by mass to 30 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 7 parts by mass to 30 parts by mass; more preferably (vii) the content of the polyfunctional epoxy group-containing substance (a1) is 10 parts by mass to 25 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 7 parts by mass to 30 parts by mass; particularly preferably (viii) the content of the polyfunctional epoxy group-containing substance (a1) is 15 parts by mass to 20 parts by mass, and the content of the monofunctional epoxy group-containing substance (a2) is 8 parts by mass to 30 parts by mass. According to this scheme, the following advantages are achieved: the composition has low viscosity and excellent processability; furthermore, the cured product obtained by curing the composition exhibits excellent strength and / or toughness. In case E, in 100 parts by weight of component (A), (i) the content of the substance (a1) containing polyfunctional epoxy groups may also be less than 95 parts by weight, and / or, (ii) the content of the substance (a2) containing monofunctional epoxy groups may also be less than 95 parts by weight or less than 40 parts by weight.

[0429] In a curable resin composition that at least satisfies the aforementioned matter (3), the specific manner relating to component (A), other than those described above, is the same as that stated in the <1-1-2.(A) component> section, therefore the relevant description is cited and its explanation is omitted here. The preferred manner relating to component (A), other than those described above, in a curable resin composition that at least satisfies the aforementioned matter (1), is also preferred in a curable resin composition that at least satisfies the aforementioned matter (3).

[0430] <1-3-3.(B) Component>

[0431] The specific manner of component (B) is the same as that described in the aforementioned <1-1-3.(B)Component> section, therefore the relevant description is cited and its explanation is omitted here. The preferred manner of component (B) in a curable resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of component (B) in a curable resin composition that at least satisfies the aforementioned matter (3).

[0432] <1-3-4. (C) Ingredients>

[0433] In a curable resin composition that at least satisfies the aforementioned condition (3), component (C) is an amine-based epoxy curing agent. In a curable resin composition that at least satisfies the aforementioned condition (3), component (C) functions as a curing agent relative to component (A). The amine-based epoxy curing agent as component (C) contains at least an amine (c4) having an average of one or two active hydrogen atoms on the amino group per molecule. In this specification, "amine (c4) having an average of one or two active hydrogen atoms on the amino group per molecule" is sometimes referred to as "amine (c4)".

[0434] Amines (C4) with an average of one or two active hydrogen atoms on the amino group per molecule

[0435] In a curable resin composition that at least satisfies the foregoing condition (3), if component (C) contains at least an amine (C4), it has the following advantages: (i) it can produce a cured product with excellent toughness and elongation properties, and (ii) it can produce a composition with low viscosity and excellent workability.

[0436] As an amine (C4), there are no particular limitations as long as the average number of active hydrogen atoms on the amino group per molecule is one or two. Examples of amines (C4) include: aliphatic amines with an average of two active hydrogen atoms on the amino group per molecule, such as 3-diethylaminopropylamine, 3-dimethylaminopropylamine, 2-diethylaminoethylamine, 2-dimethylaminoethylamine, piperazine, 2-methylpiperazine, N,N'-dimethylethylenediamine, ethanolamine, n-octylamine, 2-ethylhexylamine, n-dodecylamine, hexylamine, and cyclohexylamine; and aniline, o-toluidine, 4-chloro-o-toluidine, 2,4-dimethylmethylamine, p-methoxytoluidine, o-methoxyaniline, 2,4,6-trimethylaniline, 2-naphthylamine, and 4-aminobiphenyl, which have an average of two active hydrogen atoms on the amino group per molecule. Aromatic amines with an average of one active hydrogen atom per amino group per molecule, such as 1-(2-hydroxyethyl)piperazine, 1-methylpiperazine, piperidine, 4-methylpiperidine, diethanolamine, di-n-octylamine, di(2-ethylhexyl)amine, di-n-dodecylamine, dihexylamine, dicyclohexylamine, N-methylcyclohexylamine, N-methyl-n-octylamine, diallylamine, etc.; aromatic amines with an average of one active hydrogen atom per amino group per molecule, such as N-methylaniline, diphenylamine, N-methyl-p-toluidine, N-phenyl-p-toluidine, N-methyl-m-toluidine, N-methyl-2-naphthylamine, N-phenyl-2-naphthylamine, N-methyl-1-naphthylamine, etc.; etc.

[0437] From the viewpoint of achieving rapid curing speed and excellent productivity of the cured product, aliphatic amines with an average of one or two active hydrogen atoms on the amino group per molecule are preferred among these amines (C4), and aliphatic amines with an average of two active hydrogen atoms on the amino group per molecule are even more preferred. Furthermore, from the viewpoint of achieving a high glass transition temperature and excellent heat resistance of the resulting cured product, aromatic amines with an average of one or two active hydrogen atoms on the amino group per molecule are preferred among these amines (C4), and aromatic amines with an average of two active hydrogen atoms on the amino group per molecule are even more preferred.

[0438] From the viewpoint of achieving faster curing speed and better productivity of the cured product, among the aliphatic amines (C4) having an average of one or two active hydrogens on the amino group per molecule, aliphatic amines such as 3-diethylaminopropylamine, 3-dimethylaminopropylamine, 2-diethylaminoethylamine, 2-dimethylaminoethylamine, piperazine, 2-methylpiperazine, N,N'-dimethylethylenediamine, 1-(2-hydroxyethyl)piperazine, and 1-methylpiperazine, which have an ethylenediamine or propylenediamine backbone, are more preferred. From the viewpoint of high boiling point and low volatility, 3-diethylaminopropylamine, 2-diethylaminoethylamine, piperazine, 2-methylpiperazine, and 1-(2-hydroxyethyl)piperazine are further preferred, and 3-diethylaminopropylamine and 1-(2-hydroxyethyl)piperazine are particularly preferred.

[0439] From the above viewpoint, in a curable resin composition that at least satisfies the aforementioned matter (3), component (C) preferably includes one or more selected from 3-diethylaminopropylamine, 3-dimethylaminopropylamine, 2-diethylaminoethylamine, 2-dimethylaminoethylamine, piperazine, 2-methylpiperazine, N,N'-dimethylethylenediamine, 1-(2-hydroxyethyl)piperazine and 1-methylpiperazine as an amine (C4). In a curable resin composition that at least satisfies the foregoing (3), component (C) preferably includes, in 100% by mass, at least 20% by mass, more preferably at least 30% by mass, further preferably at least 50% by mass, even more preferably at least 70% by mass, and particularly preferably at least 100% by mass as an amine (C4): selected from 3-diethylaminopropylamine, 3-dimethylaminopropylamine, 2-diethylaminoethylamine, 2-dimethylaminoethylamine, piperazine, 2-methylpiperazine, N,N'-dimethylethylenediamine, 1-(2-hydroxyethyl)piperazine, and 1-methylpiperazine. In other words, in a curable resin composition that at least satisfies the aforementioned condition (3), component (C) is particularly preferably composed of only one or more selected from 3-diethylaminopropylamine, 3-dimethylaminopropylamine, 2-diethylaminoethylamine, 2-dimethylaminoethylamine, piperazine, 2-methylpiperazine, N,N'-dimethylethylenediamine, 1-(2-hydroxyethyl)piperazine, and 1-methylpiperazine. According to this scheme, it has the advantage of being able to obtain a cured product with excellent toughness.

[0440] In a curable resin composition that at least satisfies the aforementioned condition (3), the content of amine (C4) in component (C) is 5% to 100% by mass in 100% by mass of component (C), preferably 20% to 100% by mass, more preferably 30% to 90% by mass, further preferably 40% to 80% by mass, and particularly preferably 50% to 75% by mass. According to this scheme, it has the advantage of being able to obtain a cured product with an excellent balance of toughness and heat resistance.

[0441] Alicyclic amines (C5) with an average of 4 active hydrogen atoms on the amino group per molecule

[0442] In a curable resin composition that satisfies at least the aforementioned condition (3), component (C) preferably further comprises an alicyclic amine (C5) having an average of 4 active hydrogen atoms on the amino group per molecule. In this specification, "an alicyclic amine (C5) having an average of 4 active hydrogen atoms on the amino group per molecule" is sometimes referred to as "amine (C5)". In a curable resin composition that satisfies at least the aforementioned condition (3), if component (C) further comprises an amine (C5), it has the advantage of being able to obtain a cured product with an excellent balance between toughness and heat resistance. Here, alicyclic amines are also referred to as "cyclic aliphatic polyamines".

[0443] As an amine (C5), there is no particular limitation as long as it is an alicyclic amine (cyclic aliphatic polyamine) with an average of 4 active hydrogens on the amino group per molecule. Examples of amines (C5) include: isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), benzoxyldiamine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5.5]undecane as one of the spiroacetal diamines, norbornane diamine, and bis(aminomethyl)tricyclodecane, etc.

[0444] In a curable resin composition that at least satisfies the foregoing condition (3), component (C) may be in the following manner: preferably (i) comprising one or more selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), and phenylenediamine as an amine (C5), more preferably composed of only one or more selected from these; more preferably (ii) comprising one selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), and phenylenediamine as an amine (C5), more preferably composed of only one or more selected from these; more preferably (ii) comprising one selected from isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylenebis(2-methylcyclohexylamine), and phenylenediamine as an amine (C5). The amine (C5) comprises one or more of isophorone diamine, 1,3-bis(aminomethyl)cyclohexylamine, and 4,4'-methylenebis(cyclohexylamine), more preferably composed of only one or more of these; even more preferably (iii) it comprises one or more of isophorone diamine, 1,3-bis(aminomethyl)cyclohexane, and 4,4'-methylenebis(cyclohexylamine), more preferably composed of only one or more of these; further preferably (iv) it comprises one or more of isophorone diamine and 4,4'-methylenebis(cyclohexylamine), particularly preferably composed of only one or more of these. According to this scheme, it has the advantage of being able to obtain a cured product with excellent toughness.

[0445] The following describes the case where component (C) of the curable resin composition that at least satisfies the aforementioned condition (3) contains an amine (C5). In this case, the content of amine (C5) in component (C) is preferably 0% to 95% by mass in 100% by mass of component (C), more preferably 5% to 85% by mass, even more preferably 15% to 75% by mass, and particularly preferably 25% to 65% by mass. According to this scheme, it has the advantage of being able to obtain a cured product with an excellent balance between toughness and heat resistance.

[0446] In a curable resin composition that at least satisfies the foregoing (3), component (C) may (i) contain not only amine (C4) but also amine epoxy curing agents other than amine (C4) and amine (C5), or (ii) contain not only amine (C4) and amine (C5) but also amine epoxy curing agents other than amine (C4) and amine (C5).

[0447] Examples of amine-based epoxy curing agents other than amines (C4) and amines (C5) include aliphatic amines (excluding alicyclic amines with an average of 4 active hydrogens on the amino group per molecule) and aromatic amines with an average of 3 or more active hydrogens on the amino group per molecule.

[0448] Regarding alicyclic amines, excluding those with an average of 4 active hydrogen atoms on the amino group per molecule, examples of aliphatic amines with an average of 3 or more active hydrogen atoms on the amino group per molecule include: (i) chain aliphatic polyamines such as triethylenetetramine, diethylenetriamine, tetraethylenepentamine, dipropylenetriamine, and hexamethylenediamine, with an average of 3 or more active hydrogen atoms on the amino group per molecule; (ii) aliphatic aromatic amines such as m-xylenediamine, with an average of 3 or more active hydrogen atoms on the amino group per molecule; and (iii) alicyclic amines with an average of 3 or more active hydrogen atoms on the amino group per molecule. Additionally, amide amines, amine-terminated polyethers, amine-terminated butadiene nitrile rubber, aliphatic amine modifiers, alicyclic amine modifiers, amide amine modifiers, amine-terminated polyether modifiers, and amine-terminated butadiene nitrile rubber modifiers with an average of 3 or more active hydrogen atoms on the amino group per molecule can also be considered aliphatic amines with an average of 3 or more active hydrogen atoms on the amino group per molecule. Among these, amide amines with an average of more than 3 active hydrogens on the amino group per molecule have the advantage of being a cured product that can achieve an excellent balance between toughness and heat resistance, and are therefore preferred.

[0449] The amide amine is a compound formed by condensing a dicarboxylic acid, such as a dimer of tall oil fatty acids (dimer acid), and / or a monocarboxylic acid, such as neodecanoic acid, with a polyamine, such as triethylenetetramine and tetraethylenepentamine. Commercially available amide amines include, for example, Ancamide 910, Ancamide 350A, Versamid 140, and Versamid 115.

[0450] The amine-terminated polyether refers to an amine-terminated polyether containing a polyether backbone and having an average of 1.5 to 4 (more preferably 2 to 3) amino and / or imino groups per molecule. Examples of such amine-terminated polyethers include poly(oxypropylene)diamine, poly(oxypropylene)triamine, and poly(oxypropylene)tetraamine. Commercially available amine-terminated polyethers include Jeffamine D-230 (poly(oxypropylene)diamine), Jeffamine D-400 (poly(oxypropylene)diamine), Jeffamine D-2000 (poly(oxypropylene)diamine), Jeffamine D-4000 (poly(oxypropylene)diamine), and Jeffamine T-5000 (poly(oxypropylene)triamine) manufactured by Huntsman Corporation.

[0451] The amine-terminated butadiene nitrile rubber refers to a polybutadiene / acrylonitrile copolymer that preferably has 1.5 to 4 (more preferably 2 to 3) amino groups and / or imino groups per molecule on average, and has an acrylonitrile monomer content of 5% to 40% by mass (more preferably 10% to 35% by mass, and even more preferably 15% to 30% by mass) in the main chain. Examples of commercially available amine-terminated rubbers include Hypro 1300X16 ATBN manufactured by CVC Corporation.

[0452] Examples of amine-based curing agent modifiers include polyamine epoxy resin adducts obtained by reacting various polyamines, such as aliphatic amines and alicyclic amines, with low-equivalent epoxy resins.

[0453] Examples of alicyclic amines (cyclic aliphatic polyamines) with an average of 3 or more active hydrogen atoms on the amino group per molecule include N-aminoethylpiperazine.

[0454] In a curable resin composition that at least satisfies the aforementioned condition (3), the content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A), preferably 11 to 170 parts by mass, more preferably 12 to 150 parts by mass, even more preferably 13 to 130 parts by mass, and particularly preferably 15 to 115 parts by mass. According to this scheme, the cured product obtained by curing the composition has the advantages of excellent strength and toughness.

[0455] In a curable resin composition that at least satisfies the aforementioned condition (3), the number of active hydrogen atoms on the amino groups per molecule of component (C) is preferably 1.5 or more and less than 3.8, more preferably 1.7 to 3.7, even more preferably 1.9 to 3.6, and particularly preferably 2.2 to 3.3. According to this scheme, it has the advantage of obtaining a cured product with an excellent balance of toughness and heat resistance.

[0456] <1-3-5. (D) Component>

[0457] In a curable resin composition that at least satisfies the foregoing condition (3), the composition may contain component (D) or may not contain component (D). Regarding a curable resin composition that at least satisfies the foregoing condition (3), from the viewpoint of the toughness of the resulting cured product, the composition preferably does not contain component (D).

[0458] In a curable resin composition that at least satisfies the aforementioned matter (3), the specific manner relating to component (D), other than those described above, is the same as that stated in the <1-1-5.(D) component> section, therefore the relevant description is cited and its explanation is omitted here. The preferred manner relating to component (D), other than those described above, in a curable resin composition that at least satisfies the aforementioned matter (1), is also preferred in a curable resin composition that at least satisfies the aforementioned matter (3).

[0459] <1-3-6. Other Added Ingredients>

[0460] The specific methods for introducing other ingredients are the same as those mentioned in the aforementioned <1-1-6. Other Introduced Ingredients> section, so the relevant records are cited and their explanations are omitted here.

[0461] <1-3-7. Value Y>

[0462] Regarding a curable resin composition that at least satisfies the aforementioned condition (3), the value Y of the composition reflects the molecular weight between the crosslinking points of the composition. For a curable resin composition that at least satisfies the aforementioned condition (3), the value Y of the composition is 22 to 400, preferably 25 to 360, more preferably 30 to 320, even more preferably 35 to 280, and particularly preferably 40 to 200. The larger the value Y, the better the elongation properties of the resulting cured product. The smaller the value Y, the better the strength and heat resistance of the resulting cured product.

[0463] Regarding a curable resin composition that at least satisfies the aforementioned condition (3), the value Y of the composition can be adjusted by changing various parameters such as: (i) the average epoxy equivalent of the epoxy-containing substance (A) contained in the composition, (ii) the average active hydrogen equivalent of the amine (c4) contained in the composition, (iii) the average number of epoxy groups per molecule of the epoxy-containing substance (A) contained in the composition, (iv) the average number of active hydrogens on the amino group per molecule of the amine (c4) contained in the composition, (v) the type and amount of the curing accelerator (D) contained in the composition, and (vi) the amount of the amine (c4) contained in the composition.

[0464] <1-3-8. Viscosity of Curing Resin Compositions>

[0465] Regarding the specific manner of determining the viscosity of the curing resin composition, the same manner was described in the aforementioned section <1-1-9. Viscosity of Curing Resin Composition>, therefore the relevant description is cited but omitted here. The preferred manner of determining the viscosity of the curing resin composition in a curing resin composition that at least satisfies the aforementioned matter (1) is also the preferred manner of determining the viscosity of the curing resin composition in a curing resin composition that at least satisfies the aforementioned matter (3).

[0466] [2. Morphology of the curable resin composition]

[0467] This composition can be a single-component, two-component, or multi-component composition with three or more components. If this composition is used as an adhesive, it is preferably a two-component or multi-component curable resin composition.

[0468] When this composition is a two-component or multi-component curable resin composition, it is preferably, for example, in the following manner.

[0469] A two-component or multi-component curable resin composition containing a first component and a second component, wherein,

[0470] The first component comprises the following component (A),

[0471] The second component either does not contain component (D) below or also contains component (D) below.

[0472] The curable resin composition further comprises the following component (B):

[0473] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0474] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0475] (D) Ingredient: Curing accelerator,

[0476] The two-component or multi-component curable resin composition satisfies at least one of the following conditions (1) to (3): (1)

[0478] The second component also contains the following component (C): acid anhydride (C1), aromatic amine (C2), or alicyclic amine (C3).

[0479] Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight.

[0480] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0481] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0482] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0483] The value X of the two-component or multi-component curable resin composition is calculated by the following formula.

[0484] When component (C) is the acid anhydride (Cl), the concentration is 1.05–5.50.

[0485] When component (C) is the aromatic amine (C2) or the alicyclic amine (C3), the content is 1.30 to 9.00.

[0486] Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]; (2)

[0488] The second component further comprises the following component (C): an epoxy curing agent containing one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0489] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0490] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0491] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0492] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0493] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0494] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0495] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0496] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0497] The value Y of the two-component or multi-component curable resin composition, calculated by the following formula, is 22 to 400.

[0498] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; (3)

[0500] The second component further comprises the following component (C): an amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is one or two.

[0501] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0502] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0503] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0504] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0505] The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C).

[0506] The value Y of the two-component or multi-component curable resin composition, calculated by the following formula, is 22 to 400.

[0507] Calculation formula: Y=[273+Tmin(M)] / [E'(M)].

[0508] in,

[0509] In the formulas for calculating the value X and the value Y:

[0510] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0511] The composition (M) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0512] The contents of components (A), (C), and (D) in the composition (M) are the same as the contents of components (A), (C), and (D) in the curable resin composition.

[0513] The cured product (M) is a cured product obtained by curing the composition (M) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0514] In the formula for calculating the value X:

[0515] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as a sample under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature (°C) at which the value of E'(Meq) is obtained.

[0516] The composition (Meq) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0517] The amounts of component (A) and component (D) in the composition (Meq) are the same as the amounts of component (A) and component (D) in the curable resin composition.

[0518] When component (C) in the composition (Meq) is the acid anhydride (c1), the content of component (C) in the composition (Meq) is such that the molar amount of the acid anhydride group in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the acid anhydride group in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0519] When component (C) in the composition (Meq) is the aromatic amine (c2) or the alicyclic amine (c3), the content of component (C) in the composition (Meq) is such that the molar amount of the active hydrogen of the amine in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the active hydrogen of the amine in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0520] The cured product (Meq) is a cured product obtained by curing the composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0521] The above-described two-component or multi-component curable resin composition is also a curable resin composition according to an embodiment of the present invention, namely, this composition, which has the advantage of providing a cured product with excellent toughness.

[0522] Regarding the specific configurations (e.g., the composition of each component) of the aforementioned two-component or multi-component curable resin compositions, the foregoing descriptions (e.g., descriptions of each component) are appropriately referenced herein. Preferred configurations in the descriptions (e.g., descriptions of each component) are also preferred in the aforementioned two-component or multi-component curable resin compositions.

[0523] [3. Method for manufacturing curable resin composition]

[0524] There is no particular limitation on the method of manufacturing the curable resin composition. In the case that the composition is a one-component curable resin composition, the curable resin composition can be manufactured, for example, by mixing the (A), (B), (C), (D) as needed, and other components as needed, using a known mixing device (e.g., a planetary mixer).

[0525] This composition is preferably a composition in which the core-shell polymer particles, as component (B), are dispersed in a first-order particle state. It is preferable, for example, to manufacture such a composition using a polymer particle dispersion composition in which the core-shell polymer particles are dispersed in a first-order particle state. By using this polymer particle dispersion composition, it is easy to achieve the dispersion of the core-shell polymer particles in the composition in a first-order particle state. In the polymer particle dispersion composition, the core-shell polymer particles can also be at a high concentration.

[0526] This composition can also be manufactured by directly mixing the powder (powder, granules, or powder-granules) of the core-shell polymer particles, which is component (B), with component (A) to disperse the core-shell polymer particles in component (A). However, in order to obtain a composition in which the core-shell polymer particles are dispersed in a first-order particle state and where aggregates of the core-shell polymer particles are completely absent or present in very small amounts, it is preferable to manufacture the composition using the polymer particle dispersion composition after obtaining the aforementioned polymer particle dispersion composition.

[0527] Various methods can be used to obtain a polymer particle dispersion composition. Examples include: contacting core-shell polymer particles obtained in an aqueous latex state with component (A), and then removing unwanted components such as water; temporarily extracting the core-shell polymer particles into an organic solvent, mixing the organic solvent containing the core-shell polymer particles with component (A), and then removing the organic solvent from the resulting mixture. The method described in International Publication No. 2005 / 028546 is preferred for obtaining the polymer particle dispersion composition. Specifically, the manufacturing method involves sequentially performing the following steps 1, 2, and 3.

[0528] Step 1: An aqueous latex containing core-shell polymer particles (e.g., a reaction mixture after core-shell polymer particles have been obtained by emulsion polymerization) is mixed with an organic solvent having a solubility of 5% to 40% by weight in water at 20°C. The resulting mixture is then further mixed with an excess of water to cause the polymer particles to aggregate.

[0529] Step 2: Separate and recover the aggregated core-shell polymer particles from the liquid phase, and then mix the core-shell polymer particles with an organic solvent again to obtain an organic solvent solution of the core-shell polymer particles.

[0530] Step 3: The obtained organic solvent solution is further mixed with component (A), and then the organic solvent is distilled off from the resulting mixture.

[0531] (A) The component is preferably liquid at 23°C. (A) If the component is liquid at 23°C, the third step is easier to implement. "Liquid at 23°C" means that the softening point is below 23°C, and that it exhibits fluidity at 23°C.

[0532] Through the first to third steps described above, a polymer particle dispersion composition is obtained, in which core-shell polymer particles, as component (B), are dispersed in component (A) as primary particles. By mixing additional components (A), (B), (C), (D) as needed, and other components as needed into the obtained polymer particle dispersion composition, a composition can be obtained. In the composition thus obtained, the core-shell polymer particles can be dispersed in a primary particle state.

[0533] On the other hand, core-shell polymer particles can be coagulated using methods such as salting out, and then the resulting coagulated material can be dried to obtain powdered core-shell polymer particles. By using a disperser with high mechanical shear force, such as a three-roller printing roller, a roller mill, or a kneader, the powdered core-shell polymer particles can be redispersed into component (A) as first-order particles. At this time, by applying mechanical shear force to the mixture of component (A) and component (B) (powdered core-shell polymer particles) at high temperature, component (B) can be effectively dispersed into component (A). The temperature during dispersion (when shear force is applied) is preferably 50°C to 200°C, more preferably 70°C to 170°C, further preferably 80°C to 150°C, and particularly preferably 90°C to 120°C.

[0534] When this composition is a two-component or multi-component curable resin composition comprising a first component and a second component, the first component comprising component (B) can be prepared by mixing component (A) and component (B), and other components as needed, using a known mixing apparatus (e.g., a planetary mixer). Regarding the first component comprising components (A) and (B), it is preferable that the core-shell polymer particles, as component (B), are dispersed in component (A) in a first-order particle state. In other words, the first component comprising components (A) and (B) can also be the polymer particle dispersion composition described above. Furthermore, the second component can be prepared by mixing component (C) and component (D) as needed, and component (B) and other components as needed, using a known mixing apparatus (e.g., a planetary mixer). The first and second components thus prepared are preferably mixed and used immediately before use (e.g., just before bonding the substrates or before the curable resin composition is cured).

[0535] In the case where this composition is a two-component or multi-component curable resin composition comprising a first component and a second component, as another example, a first component without component (B) can be prepared by mixing component (A) and other components as needed using a known mixing apparatus (e.g., a planetary mixer). Alternatively, a second component containing component (B) can be prepared by mixing component (B), component (C), and component (D) as needed, and other components as needed, using a known mixing apparatus (e.g., a planetary mixer). The first and second components thus prepared are preferably mixed and used immediately before use (e.g., just before bonding the substrates or before the curable resin composition is cured).

[0536] When the second component contains components (C) and (D), storage stability issues sometimes arise, such as an increase in viscosity after storage. In particular, when the second component contains an anhydride (C1) as component (C) and an imidazole such as 2-ethyl-4-methylimidazolium as component (D), the viscosity of the second component tends to increase over time due to the reaction between the anhydride (C1) and the imidazole. If a second component premixed with an anhydride (C1) and component (D) is used, component (D) is preferably a tertiary amine such as 2,4,6-tris(dimethylaminomethyl)phenol, N-benzyldimethylamine, or a quaternary ammonium salt such as benzyltriethylammonium chloride; more preferably, it is a tertiary amine without phenolic hydroxyl groups such as N-benzyldimethylamine or a quaternary ammonium salt such as benzyltriethylammonium chloride; and especially preferably, it is a quaternary ammonium salt such as benzyltriethylammonium chloride. This results in less viscosity change after storage and excellent storage stability.

[0537] 〔4.Cured material〕

[0538] The cured product of one embodiment of the present invention is a cured product obtained by curing the cured resin composition described in the aforementioned section [1. Curable Resin Composition], and / or the cured resin composition obtained by the manufacturing method described in the aforementioned section [3. Method for Manufacturing Curable Resin Composition]. In this specification, "the cured product of one embodiment of the present invention" will sometimes be referred to as "this cured product". This cured product can also be described as a cured product formed by curing this composition. This cured product can also be described as a cured product containing this cured product.

[0539] This cured material possesses the aforementioned technical structure, and therefore has the advantage of excellent toughness.

[0540] In this solidified product, the polymer particles, which are component (B), are preferably dispersed in the form of primary particles.

[0541] The method for manufacturing this cured product, or in other words, the method for curing this composition, is not particularly limited. For example, if the composition is a single-component type, a cured product can be obtained by heating the composition to a certain temperature (curing temperature) and maintaining the composition at the curing temperature for a certain time (curing time). If the composition is a two-component or multi-component type composition containing a first component and a second component, a cured product can be obtained by uniformly mixing the first component and the second component using a static mixer or the like, heating the resulting mixture to a certain temperature (curing temperature), and maintaining the mixture at the curing temperature for a certain time (curing time).

[0542] The curing temperature is not particularly limited as long as it is sufficient to cure the composition or mixture. The preferred curing temperature is 50°C to 200°C, more preferably 70°C to 180°C, and particularly preferably 90°C to 150°C. When the curing temperature is above 50°C, the curing reaction can be fully promoted. When the curing temperature is below 200°C, the physical properties and / or quality of the resulting cured product will not decrease.

[0543] The curing time is not particularly limited as long as it is sufficient to cure the composition or mixture. The curing time is preferably 0.5 hours to 12 hours, more preferably 0.5 hours to 6 hours, even more preferably 1 hour to 4 hours, and particularly preferably 1 hour to 2 hours.

[0544] [5. Adhesive]

[0545] An adhesive according to one embodiment of the present invention is an adhesive containing, for example, the curable resin composition described in the aforementioned section [1. Curable Resin Composition], and / or a curable resin composition obtained by the manufacturing method described in the aforementioned section [3. Method for Manufacturing Curable Resin Composition]. In this specification, "an adhesive according to one embodiment of the present invention" will sometimes be referred to as "this adhesive." This adhesive can also be described as an adhesive containing this composition.

[0546] This adhesive has the aforementioned technical structure, and therefore has the advantages of excellent toughness and bonding strength in the cured product.

[0547] In this adhesive, the polymer particles, which are component (B), are preferably dispersed in the form of primary particles.

[0548] This adhesive is preferably a two-component or multi-component adhesive. When this adhesive is a two-component or multi-component adhesive, it may, for example, be an adhesive containing a two-component or multi-component curable resin composition described in the aforementioned section [2. Form of Curable Resin Composition]. Alternatively, when this adhesive is a two-component or multi-component adhesive, it may also be, for example, in the following manner.

[0549] A two-component or multi-component adhesive comprising a first component and a second component, wherein,

[0550] The first component comprises the following component (A),

[0551] The second component either does not contain component (D) below or also contains component (D) below.

[0552] The adhesive also contains the following component (B).

[0553] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0554] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0555] (D) Ingredient: Curing accelerator,

[0556] The two-component or multi-component adhesive satisfies at least one of the following conditions (1) to (3): (1)

[0558] It also contains the following components (C): acid anhydride (C1), aromatic amine (C2) or alicyclic amine (C3).

[0559] Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight.

[0560] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0561] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0562] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0563] The value X of the two-component or multi-component adhesive is calculated by the following formula.

[0564] When component (C) is the acid anhydride (Cl), the concentration is 1.05–5.50.

[0565] When component (C) is the aromatic amine (C2) or the alicyclic amine (C3), the content is 1.30 to 9.00.

[0566] Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]; (2)

[0568] It also contains the following component (C): Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0569] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0570] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0571] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0572] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0573] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0574] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0575] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0576] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0577] The value Y of this two-component or multi-component adhesive, calculated by the following formula, is 22 to 400.

[0578] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; (3)

[0580] It also contains the following component (C): amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is 1 or 2.

[0581] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0582] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0583] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0584] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0585] The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C).

[0586] The value Y of this two-component or multi-component adhesive, calculated by the following formula, is 22 to 400.

[0587] Calculation formula: Y=[273+Tmin(M)] / [E'(M)].

[0588] in,

[0589] In the formulas for calculating the value X and the value Y:

[0590] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0591] The composition (M) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0592] The contents of components (A), (C), and (D) in the composition (M) are the same as the contents of components (A), (C), and (D) in the curable resin composition.

[0593] The cured product (M) is a cured product obtained by curing the composition (M) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0594] In the formula for calculating the value X:

[0595] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as a sample under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature (°C) at which the value of E'(Meq) is obtained.

[0596] The composition (Meq) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0597] The amounts of component (A) and component (D) in the composition (Meq) are the same as the amounts of component (A) and component (D) in the curable resin composition.

[0598] When component (C) in the composition (Meq) is the acid anhydride (c1), the content of component (C) in the composition (Meq) is such that the molar amount of the acid anhydride group in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the acid anhydride group in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0599] When component (C) in the composition (Meq) is the aromatic amine (c2) or the alicyclic amine (c3), the content of component (C) in the composition (Meq) is such that the molar amount of the active hydrogen of the amine in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the active hydrogen of the amine in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0600] The cured product (Meq) is a cured product obtained by curing the composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0601] When this adhesive is a two-component or multi-component adhesive, it may be in the following manner, for example.

[0602] A two-component or multi-component adhesive comprising a first component and a second component, wherein,

[0603] The first component comprises the following component (A),

[0604] The second component comprises component (C) below and does not contain component (D) below, or further comprises component (D) below.

[0605] The adhesive also contains the following component (B).

[0606] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0607] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0608] (C) Composition: Amine-based epoxy curing agent containing amine (c1), wherein the average number of active hydrogens on the amino group of each molecule of the amine (c1) is 1 or 2;

[0609] (D) Ingredient: Curing accelerator,

[0610] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0611] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0612] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0613] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0614] The content of the amine (c1) in component (C) is 5% to 100% by mass in 100% of component (C).

[0615] This two-component or multi-component adhesive

[0616] The value of Y calculated by the following formula is 22 to 400.

[0617] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]

[0618] in,

[0619] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0620] The composition (M) comprises the same components (A), (C), and (D) as those contained in the adhesive.

[0621] The amounts of components (A), (C), and (D) in the composition (M) are the same as the amounts of components (A), (C), and (D) in the adhesive.

[0622] The cured product (M) is, for example, a cured product obtained by curing the composition (M) at a curing temperature of 120°C and a curing time of 2 hours.

[0623] This adhesive is well-suited for a variety of applications, including structural adhesives designed for vehicles and aircraft, structural adhesives for wind power generation, automotive interior materials, general woodworking, furniture, home interiors, wall materials, and food packaging. Its excellent toughness makes it particularly suitable for use as a structural adhesive in vehicles.

[0624] Furthermore, this adhesive can cure even at curing temperatures near room temperature and exhibits excellent toughness, making it suitable for bonding dissimilar substrates with different coefficients of linear expansion. For example, it is suitable for bonding steel plates and aluminum.

[0625] This adhesive can bond wood, metal, plastic, glass, and other materials. It exhibits excellent adhesion to various substrates, including: cold-rolled steel, aluminum, fiberglass reinforced polyester (FRP), carbon fiber reinforced cured panels made from thermosetting resins such as epoxy resin, carbon fiber reinforced thermoplastic resin sheets, sheet molding compound (SMC), acrylonitrile-butadiene-styrene copolymer (ABS), polyvinyl chloride (PVC), polycarbonate, polypropylene, TPO, wood, and glass.

[0626] The curing temperature of this adhesive is not particularly limited as long as it allows the composition or mixture to cure. When this adhesive is a two-component or multi-component adhesive, the curing temperature is preferably 5°C to 50°C, more preferably 10°C to 45°C, and particularly preferably 20°C to 40°C. A curing temperature of 5°C or higher has the advantage of allowing the curing reaction to proceed sufficiently. A curing temperature of 50°C or lower has the advantage of allowing the cured product to be obtained through a highly economical production process at around room temperature.

[0627] This adhesive can be prepared using this composition. There are no particular limitations on the manufacturing method of this adhesive; known methods can be used.

[0628] [6. Layered structures]

[0629] A laminate according to one embodiment of the present invention comprises: at least two substrates; and an adhesive layer formed by bonding the at least two substrates together and curing the adhesive described in the aforementioned [5. Adhesive] section, i.e., the adhesive according to one embodiment of the present invention. In this specification, the term "laminate according to one embodiment of the present invention" is sometimes referred to as "this laminate".

[0630] This laminate has the aforementioned technical configuration, and therefore has the advantage of exhibiting high adhesive strength.

[0631] (Substrate)

[0632] There are no particular limitations on the substrate. Examples of substrates include wood, metal, plastic, and glass. One of the above examples can be used alone, or two or more can be used in combination.

[0633] Examples of metals include cold-rolled steel and hot-dip galvanized steel, and aluminum and coated aluminum. Examples of plastics include general-purpose plastics, engineering plastics, and various plastic substrates such as composite materials (e.g., CFRP and GFRP).

[0634] The manufacturing method of this laminate is not particularly limited. For example, this laminate can be obtained by applying the adhesive to one or both of at least two substrates, then sandwiching the composition between the substrates and bonding them together, and then curing the adhesive, thereby bonding the substrates. When the adhesive is a two-component or multi-component adhesive containing a first component and a second component, the substrates can be bonded by uniformly mixing the first and second components using a static mixer or the like, applying the resulting mixture to one or both of at least two substrates, then sandwiching the mixture between the substrates and bonding them together, and then curing the mixture.

[0635] There are no particular restrictions on the curing conditions. For example, by heating the adhesive to a temperature of 80°C or higher, preferably 130°C or higher, more preferably 150°C or higher, and curing the adhesive for 30 minutes or less, more preferably 20 minutes or less, an adhesive layer can be formed, thereby obtaining a laminate composed of at least two substrates bonded together.

[0636] In the case of a two-component or multi-component adhesive, there are no particular restrictions on the curing conditions. For example, the adhesive can be cured at a temperature of 5°C to 50°C, preferably 10°C to 45°C, more preferably 20°C to 40°C, and preferably within 60 minutes, more preferably within 30 minutes, to form an adhesive layer, thereby obtaining a laminate composed of at least two substrates bonded together.

[0637] From the viewpoint of the adhesive strength of the laminate, the thickness of the adhesive layer of this laminate is preferably 0.001 mm to 5.000 mm, more preferably 0.01 mm to 1.000 mm, and even more preferably 0.10 mm to 0.30 mm. Here, the thickness of the adhesive layer of this laminate can also be referred to as the thickness of the adhesive.

[0638] [7. Fiber-reinforced composite materials]

[0639] The fiber-reinforced composite material of one embodiment of the present invention comprises, for example, the curable resin composition described in the aforementioned section [1. Curable Resin Composition], and / or, the curable resin composition obtained by the manufacturing method described in the aforementioned section [3. Method for Manufacturing Curable Resin Composition], and other such curable resin compositions of one embodiment of the present invention; and fibers. In this specification, "the fiber-reinforced composite material of one embodiment of the present invention" is sometimes referred to as "this fiber-reinforced composite material".

[0640] This fiber-reinforced composite material possesses the aforementioned technical configuration, thus exhibiting excellent toughness. Fiber-reinforced composite materials are sometimes required to have heat resistance. The cured product of the aforementioned composition also possesses the advantages of a high glass transition temperature and excellent heat resistance. Therefore, this fiber-reinforced composite material also has the advantage of excellent heat resistance. In other words, this composition, by combining with fibers, is particularly suitable for fields requiring fiber-reinforced composite materials with heat resistance.

[0641] (fiber)

[0642] The fiber is not particularly limited. Examples of fibers include glass fiber, carbon fiber, aramid fiber, and boron fiber. From the viewpoint of obtaining a fiber-reinforced composite material with excellent mechanical properties such as lightweight, strength, and elastic modulus, the fiber preferably contains carbon fiber, and is particularly preferably carbon fiber (composed solely of carbon fiber). One of the aforementioned fibers can be used alone, or two or more can be used in combination.

[0643] Examples of carbon fibers include PAN-based fibers, pitch-based fibers, and rayon-based fibers. One of the aforementioned types can be used alone, or two or more can be used in combination.

[0644] The fiber can be either a short fiber or a continuous fiber, or a combination of both. The fiber can be used in the form of strands or as a fiber substrate. As a fiber substrate, it can be a substrate in which the fibers are drawn in one direction, or a substrate composed of fibers drawn in one direction (warp yarns) and glass or synthetic fibers (weft yarns) that hold the fibers in place. Specifically, non-crimped fabrics, mats, woven fabrics, knitted fabrics, and braided fabrics can be used as fiber substrates.

[0645] Fiber-reinforced composites can be obtained by impregnating the composition with fibers and then curing the composition.

[0646] Specific examples of impregnation methods for impregnating the composition into fibers are as follows, but the impregnation methods are not limited to those described below. For example, methods such as: (i) forming a film of the composition, which is heated as needed, using a pressure roller and / or on release paper, then transferring the film to one or both sides of the fiber, and impregnating the resulting laminate with a bending roller or pressure roller; (ii) coating the fiber with the composition, which is heated as needed, to impregnate the composition; or (iii) heating a tank filled with the composition as needed, and impregnating the fiber with the composition in the tank.

[0647] This composition is well suited for the manufacture of fiber-reinforced composite materials as described above.

[0648] As described later, this fiber-reinforced composite material is well-suited for use as a material for constructing wheel discs (especially vehicle wheel discs). Additionally, as described later, this fiber-reinforced composite material is also well-suited for covering the outer surface of tank liners to construct pressure vessels (e.g., high-pressure vessels). However, this fiber-reinforced composite material is not limited to these applications; it is also well-suited for structural components and / or outer panels of aircraft, spacecraft, automobiles, industrial machinery, railway vehicles, ships, etc.

[0649] There are no particular limitations on the molding method for obtaining the fiber-reinforced composite material for the above-mentioned purposes. Known methods that involve impregnating a liquid composition into fibers and then curing the resulting impregnated composition can be utilized. Specifically, examples include: hand lay-up molding, fiber filament winding, pultrusion molding, wet molding, prepreg, vacuum bag molding, pressure bag molding, spray molding, high-pressure can molding, matte molding, sheet molding compound (SMC), block molding compound (BMC), continuous lamination, resin transfer molding (RTM), high-pressure resin transfer molding (HP-RTM), and vacuum-assisted resin transfer molding (VaRTM). From the viewpoint of relatively high productivity and the ability to obtain fiber-reinforced composite materials with complex shapes, RTM and VaRTM are preferred. Here, RTM refers to a method in which reinforcing fibers are arranged in a closed mold made of rigid material and pressure is applied to inject a liquid resin composition into the closed mold. In addition, VARTM refers to a method in which reinforcing fibers are placed between an open mold made of rigid material and a flexible film (bag), and a liquid resin composition is injected therein using vacuum pressure reduction. Alternatively, fiber winding molding can also be used effectively.

[0650] [8. Roulette]

[0651] The roulette wheel of one embodiment of the present invention comprises the fiber-reinforced composite material described in the aforementioned section [7. Fiber-Reinforced Composite Material], namely, the fiber-reinforced composite material of one embodiment of the present invention. In this specification, "the roulette wheel of one embodiment of the present invention" will sometimes be referred to as "this roulette wheel". This roulette wheel can also be described as a roulette wheel made using this fiber-reinforced composite material. This roulette wheel possesses the aforementioned technical configuration and therefore has the advantage of excellent toughness.

[0652] This wheel is preferably used in vehicles such as aircraft landing gear wheels, spacecraft wheels, automobile wheels, and railway vehicle wheels. Vehicle wheel discs require toughness. This wheel disc exhibits excellent toughness, making it particularly suitable for use as a vehicle wheel disc. In other words, one embodiment of the present invention provides a vehicle wheel disc comprising the fiber-reinforced composite material described in the aforementioned section [7. Fiber-Reinforced Composite Materials], i.e., the fiber-reinforced composite material of one embodiment of the present invention.

[0653] There are no particular limitations on the manufacturing method (molding method) for obtaining fiber-reinforced composite materials for wheel discs, especially vehicle wheel discs. Methods such as sheet molding compound (SMC), resin transfer molding (RTM), high pressure resin transfer molding (HP-RTM), and vacuum-assisted resin transfer molding (VaRTM) can be used well.

[0654] [9. High-pressure vessel]

[0655] A high-pressure vessel according to one embodiment of the present invention contains the fiber-reinforced composite material described in the aforementioned section [7. Fiber-Reinforced Composite Material], i.e., the fiber-reinforced composite material of one embodiment of the present invention. In this specification, "a high-pressure vessel according to one embodiment of the present invention" is sometimes referred to as "this high-pressure vessel." This high-pressure vessel can also be described as a high-pressure vessel made using this fiber-reinforced composite material. This high-pressure vessel possesses the aforementioned technical configuration and therefore has the advantage of excellent toughness.

[0656] If manufacturing pressure vessels (including this high-pressure vessel), fibers obtained by impregnating fibers with a composition (hereinafter sometimes referred to as "composition-impregnated fibers") can be wound onto the outer surface of a sealed, gas-barrier plastic or metal hollow container (also called a tank liner) using a fiber winding method. When winding the composition-impregnated fibers onto the tank liner, known circumferential winding methods, low-angle or high-angle helical winding methods, etc., can be used. Then, the composition-impregnated fibers are heated to a predetermined curing temperature to cure the composition, thereby manufacturing a pressure vessel (including this high-pressure vessel) containing fiber-reinforced composite materials. The resulting pressure vessel can be used less frequently as a high-pressure vessel (e.g., a high-pressure hydrogen tank). The curing temperature is not particularly limited, but is preferably around 50°C to 250°C, more preferably 80°C to 200°C, and particularly preferably 100°C to 150°C.

[0657] Another embodiment of the present invention may be as follows.

[0658] [1] A curable resin composition,

[0659] It contains component (A) and component (B) below, and does not contain component (D) below, or also contains component (D) below.

[0660] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0661] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0662] (D) Ingredient: Curing accelerator,

[0663] Furthermore, the curable resin composition satisfies at least one of the following conditions (1) to (3): (1)

[0665] It also contains the following components (C): acid anhydride (C1), aromatic amine (C2) or alicyclic amine (C3).

[0666] Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight.

[0667] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0668] The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A).

[0669] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0670] The value X of the curable resin composition is calculated by the following formula.

[0671] When component (C) is the acid anhydride (Cl), the concentration is 1.05–5.50.

[0672] When component (C) is the aromatic amine (C2) or the alicyclic amine (C3), the content is 1.30 to 9.00.

[0673] Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]; (2)

[0675] It also contains the following component (C): Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0676] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0677] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0678] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0679] When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A).

[0680] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0681] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0682] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0683] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0684] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0685] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; (3)

[0687] It also contains the following component (C): amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is 1 or 2.

[0688] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0689] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0690] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0691] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0692] The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C).

[0693] The value Y of the curable resin composition, calculated by the following formula, is 22 to 400.

[0694] Calculation formula: Y=[273+Tmin(M)] / [E'(M)].

[0695] in,

[0696] In the formulas for calculating the value X and the value Y:

[0697] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0698] The composition (M) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0699] The contents of components (A), (C), and (D) in the composition (M) are the same as the contents of components (A), (C), and (D) in the curable resin composition.

[0700] The cured product (M) is a cured product obtained by curing the composition (M) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0701] In the formula for calculating the value X:

[0702] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as a sample under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature (°C) at which the value of E'(Meq) is obtained.

[0703] The composition (Meq) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0704] The amounts of component (A) and component (D) in the composition (Meq) are the same as the amounts of component (A) and component (D) in the curable resin composition.

[0705] When component (C) in the composition (Meq) is the acid anhydride (c1), the content of component (C) in the composition (Meq) is such that the molar amount of the acid anhydride group in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the acid anhydride group in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0706] When component (C) in the composition (Meq) is the aromatic amine (c2) or the alicyclic amine (c3), the content of component (C) in the composition (Meq) is such that the molar amount of the active hydrogen of the amine in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq) (molar amount of the active hydrogen of the amine in component (C) / molar amount of the epoxy group in component (A)) is 1.

[0707] The cured product (Meq) is a cured product obtained by curing the composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

[0708] [2] The curable resin composition according to [1], wherein component (B) contains at least one polymer particle selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3).

[0709] Polymer particles (B-1): The shell of the polymer particles has epoxy groups, and the content of the epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell.

[0710] Polymer Particles (B-2): The core layer of these polymer particles is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture comprises (b1) 50.00% to 99.99% by mass of a conjugated diene monomer, (b2) 0.00% to 49.99% by mass of a vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) 0.01% to 3.00% by mass of a chain transfer agent, wherein the total of (b1) the conjugated diene monomer, (b2) the vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) the chain transfer agent is 100% by mass.

[0711] Polymer Particle (B-3): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture. The shell layer of the polymer particle has epoxy groups, and the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer. The monomer mixture comprises (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents. The total mass of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0712] [3] The curable resin composition according to [1] or [2], wherein the core layer of the (B) component is butadiene rubber and / or butadiene-styrene rubber.

[0713] [4] The curable resin composition according to any one of [1] to [3], wherein the shell layer comprises one or more structural units selected from aromatic vinyl units, vinyl cyanide units and (meth)acrylate units.

[0714] [5] The curable resin composition according to any one of [1] to [4], wherein, when the curable resin composition satisfies the condition (1),

[0715] The (C) component is the acid anhydride (c1), and the content of the (C) component in the curable resin composition is such that the molar amount of the acid anhydride group in the (C) component relative to the molar amount of the epoxy group in the (A) component contained in the curable resin composition (molar amount of the acid anhydride group in the (C) component / molar amount of the epoxy group in the (A) component) is 0.35 to 0.87.

[0716] [6] The curable resin composition according to any one of [1] to [4], wherein, when the curable resin composition satisfies the condition (1),

[0717] The component (C) is the aromatic amine (C2) or the alicyclic amine (C3), and the content of the component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in the component (C) relative to the molar amount of epoxy groups in the component (A) contained in the curable resin composition (molar amount of active hydrogen of the amine in the component (C) / molar amount of epoxy groups in the component (A)) is 0.67 to 0.87 or 1.10 to 2.40.

[0718] [7] The curable resin composition according to any one of [1] to [4], wherein, when the curable resin composition satisfies the condition (1),

[0719] The component (C) is the aromatic amine (C2) or the alicyclic amine (C3), and the content of the component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in the component (C) relative to the molar amount of epoxy group in the component (A) contained in the curable resin composition (molar amount of active hydrogen of the amine in the component (C) / molar amount of epoxy group in the component (A)) is 0.67 to 0.87.

[0720] [8] The curable resin composition according to any one of [1] to [7], wherein, when the curable resin composition satisfies the matter (1) and / or the matter (2),

[0721] The component (A) further contains glycidylamine type epoxy resin, and the content of glycidylamine type epoxy resin in 100 parts by weight of component (A) is less than 29 parts by weight.

[0722] [9] The curable resin composition according to any one of [1] to [8], wherein, when the curable resin composition satisfies the condition (1),

[0723] The (A) component satisfies any one of the following conditions (i), (ii) or (iii):

[0724] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0725] (ii) The component (A) comprises a monofunctional epoxy group containing a single epoxy group in one molecule (a2), wherein the content of the monofunctional epoxy group containing the single epoxy group (a2) is 5 to 40 parts by mass in 100 parts by mass of the component (A).

[0726] (iii) The component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of the component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of the component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 40 parts by mass.

[0727]

[10] The curable resin composition according to any one of [1] to [4], wherein the curable resin composition satisfies the foregoing condition (3),

[0728] The number of active hydrogen atoms on the amino group in each molecule of component (C) is more than 1.5 and less than 3.8.

[0729]

[11] A cured product, which is formed by curing the curable resin composition described in any one of [1] to

[10] .

[0730]

[12] A laminate comprising: at least two substrates; and an adhesive layer formed by bonding the at least two substrates and cured by an adhesive comprising a curable resin composition of any one of [1] to

[10] .

[0731]

[13] A fiber-reinforced composite material comprising any one of [1] to

[10] a curable resin composition and fibers.

[0732]

[14] A wheel comprising the fiber-reinforced composite material described in

[13] .

[0733]

[15] A high-pressure vessel comprising the fiber-reinforced composite material described in

[13] .

[0734] Another embodiment of the present invention may be as follows.

[0735] [A1] A curable resin composition comprising components (A), (B), and (C) below, and excluding component (D) below, or further comprising component (D) below.

[0736] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0737] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0738] (C) Components: acid anhydride (c1) or aromatic amine (c2);

[0739] (D) Ingredient: Curing accelerator,

[0740] Of the 100 parts by weight of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin is 60 to 100 parts by weight; the content of component (B) is 1 to 100 parts by weight relative to 100 parts by weight of component (A); the content of component (C) is 10 to 200 parts by weight relative to 100 parts by weight of component (A); and when component (D) is included, the content of component (D) is 0.1 to 10.0 parts by weight relative to 100 parts by weight of component (A).

[0741] When component (C) is the acid anhydride (c1), the value X of the curable resin composition calculated by the following formula is 1.05 to 5.50; when component (C) is the aromatic amine (c2), the value X of the curable resin composition calculated by the following formula is 1.30 to 9.00.

[0742] Calculation formula: X={[273+Tmin] (M)} / [273+Tmin (Meq) ]}×[E' (Meq) ] / [E' (M) ]

[0743] in,

[0744] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as the sample and under tensile mode and frequency of 1 Hz, is Ttg. (M) (°C), the E' (M) This indicates that the cured product (M) is in [Ttg] (M) (°C)]~[Ttg (M) The minimum value of the energy storage elastic modulus (E') in the temperature range of +25°C, wherein Tmin (M) (°C) indicates that the E' was obtained (M) The temperature (°C) at which the value is ,

[0745] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurements performed on the cured product (Meq) of the composition (Meq) under tensile conditions and a frequency of 1 Hz, is Ttg. (Meq) (°C), the E' (Meq) This indicates that the cured product (Meq) is in [Ttg] (Meq) (°C)]~[Ttg (Meq) The minimum value of the energy storage elastic modulus (E') in the temperature range of +25°C, wherein Tmin (Meq) (°C) indicates that the E' was obtained (Meq) The temperature (°C) at which the value is ,

[0746] The composition (M) comprises the same components (A), (C), and (D) as those in the curable resin composition, and the amounts of components (A), (C), and (D) in the composition (M) are the same as those in the curable resin composition.

[0747] The composition (Meq) comprises the same components (A), (C), and (D) as those in the curable resin composition. The amounts of components (A) and (D) in the composition (Meq) are the same as those in the curable resin composition. When component (C) in the composition (Meq) is the acid anhydride (Cl), the amount of component (C) in the composition (Meq) is such that the molar amount of the anhydride groups in component (C) is relative to the composition. The amount in which the molar ratio of the epoxy groups in component (A) of the composition (Meq) (the molar ratio of the anhydride groups in component (C) / the molar ratio of the epoxy groups in component (A)) is 1, when component (C) in the composition (Meq) is the aromatic amine (c2), the amount of component (C) in the composition (Meq) is such that the molar ratio of the active hydrogen in component (C) to the molar ratio of the epoxy groups in component (A) of the composition (Meq) (the molar ratio of the active hydrogen in component (C) / the molar ratio of the epoxy groups in component (A)) is 1.

[0748] [A2] The curable resin composition according to [A1], wherein component (B) contains at least one polymer particle selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3).

[0749] The polymer particle (B-1): The shell of the polymer particle has epoxy groups, and the content of the epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell. The polymer particle (B-2): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of a chain transfer agent. The total content of the (b1) conjugated diene monomers, the (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and the (b3) chain transfer agent is... 100% by mass; the polymer particles (B-3): the core layer of the polymer particles is a diene rubber obtained by polymerizing a monomer mixture, the shell layer of the polymer particles has epoxy groups, the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer, wherein the monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, the total of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0750] [A3] The curable resin composition according to [A1] or [A2], wherein the (C) component is the acid anhydride (c1), and the content of the (C) component in the curable resin composition is such that the molar amount of the acid anhydride group in the (C) component relative to the molar amount of the epoxy group in the (A) component contained in the curable resin composition (molar amount of the acid anhydride group in the (C) component / molar amount of the epoxy group in the (A) component) is 0.35 to 0.87.

[0751] [A4] The curable resin composition according to [A1] or [A2], wherein the (C) component is the aromatic amine (c2), and the content of the (C) component in the curable resin composition is such that the molar amount of active hydrogen of the amine in the (C) component relative to the molar amount of epoxy groups in the (A) component contained in the curable resin composition (molar amount of active hydrogen of the amine in the (C) component / molar amount of epoxy groups in the (A) component) is 0.67 to 0.87 or 1.10 to 2.40.

[0752] [A5] The curable resin composition according to [A1] or [A2], wherein the (C) component is the aromatic amine (c2), and the content of the (C) component in the curable resin composition is such that the molar amount of active hydrogen of the amine in the (C) component relative to the molar amount of epoxy groups in the (A) component contained in the curable resin composition (molar amount of active hydrogen of the amine in the (C) component / molar amount of epoxy groups in the (A) component) is 0.67 to 0.87.

[0753] [A6] A curable resin composition according to any one of [A1] to [A5], wherein component (A) further comprises a glycidylamine type epoxy resin.

[0754] Of the 100 parts by weight of component (A), the content of the glycidylamine type epoxy resin is less than 29 parts by weight.

[0755] [A7] A curable resin composition according to any one of [A1] to [A6], wherein the component (A) satisfies any one of the following: (i), (ii) or (iii):

[0756] (i) Component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having two or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of component (A) is 5 parts by mass to 100 parts by mass; (ii) Component (A) comprises a monofunctional epoxy group-containing substance (a2) having one epoxy group in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of component (A) is... (iii) The content of the monofunctional epoxy group-containing substance (a2) is 5 parts by mass to 40 parts by mass; the component (A) comprises the polyfunctional epoxy group-containing substance (a1) and the monofunctional epoxy group-containing substance (a2), wherein in 100 parts by mass of component (A), the content of the polyfunctional epoxy group-containing substance (a1) is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the monofunctional epoxy group-containing substance (a2) is 5 parts by mass to 40 parts by mass.

[0757] [A8] The curable resin composition according to [A2], wherein the core layer of the polymer particles (B-1) contains one or more selected from diene rubber, (meth)acrylate rubber and organosiloxane rubber.

[0758] [A9] A cured product, which is formed by curing the curable resin composition described in any one of [A1] to [A8].

[0759] [A10] A fiber-reinforced composite material comprising any one of [A1] to [A8] a curable resin composition and fibers.

[0760] [A11] The fiber-reinforced composite material according to [A10], wherein the fiber is carbon fiber.

[0761] [A12] A wheel comprising the fiber-reinforced composite material described in [A10] or [A11].

[0762] [A13] A wheel disc for a vehicle comprising the fiber-reinforced composite material described in [A10] or [A11].

[0763] Another embodiment of the present invention may be as follows.

[0764] [B1] A curable resin composition comprising components (A), (B), and (C) below, and excluding component (D) below, or further comprising component (D) below.

[0765] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0766] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0767] (C) Component: Alicyclic amine;

[0768] (D) Ingredient: Curing accelerator,

[0769] Of the 100 parts by weight of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin is 60 to 100 parts by weight; the content of component (B) is 1 to 100 parts by weight relative to the 100 parts by weight of component (A); the content of component (C) is 5 to 200 parts by weight relative to the 100 parts by weight of component (A); and when component (D) is included, the content of component (D) is 0.1 to 10.0 parts by weight relative to the 100 parts by weight of component (A).

[0770] The value X of this curable resin composition, calculated by the following formula, is 1.30 to 9.00.

[0771] Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]

[0772] in,

[0773] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0774] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as a sample under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature (°C) at which the value of E'(Meq) is obtained.

[0775] The composition (M) comprises the same components (A), (C), and (D) as those in the curable resin composition, and the amounts of components (A), (C), and (D) in the composition (M) are the same as those in the curable resin composition.

[0776] The composition (Meq) comprises the same components (A), (C), and (D) as those contained in the curable resin composition, wherein the amounts of components (A) and (D) in the composition (Meq) are the same as those in the curable resin composition, and the amount of component (C) in the composition (Meq) is such that the ratio of the molar amount of active hydrogen of the amine in component (C) to the molar amount of epoxy group in component (A) contained in the composition (Meq) (molar amount of active hydrogen of the amine in component (C) / molar amount of epoxy group in component (A)) is 1.

[0777] [B2] The curable resin composition according to [B1], wherein component (B) contains at least one type of polymer particles selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3).

[0778] The polymer particle (B-1): The shell of the polymer particle has epoxy groups, and the content of the epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell. The polymer particle (B-2): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of a chain transfer agent. The total content of the (b1) conjugated diene monomers, the (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and the (b3) chain transfer agent is... 100% by mass; the polymer particles (B-3): the core layer of the polymer particles is a diene rubber obtained by polymerizing a monomer mixture, the shell layer of the polymer particles has epoxy groups, the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer, wherein the monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, the total of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0779] [B3] The curable resin composition according to [B1] or [B2], wherein the content of component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in component (C) relative to the molar amount of epoxy groups in component (A) contained in the curable resin composition (molar amount of active hydrogen of the amine in component (C) / molar amount of epoxy groups in component (A)) is 0.67 to 0.87 or 1.10 to 2.40.

[0780] [B4] The curable resin composition according to [B1] or [B2], wherein the content of component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in component (C) relative to the molar amount of epoxy groups in component (A) contained in the curable resin composition (molar amount of active hydrogen of the amine in component (C) / molar amount of epoxy groups in component (A)) is 0.67 to 0.87.

[0781] [B5] A curable resin composition according to any one of [B1] to [B4], wherein component (A) further comprises a glycidylamine type epoxy resin.

[0782] Of the 100 parts by weight of component (A), the content of the glycidylamine type epoxy resin is less than 29 parts by weight.

[0783] [B6] A curable resin composition according to any one of [B1] to [B5], wherein the (A) component satisfies any one of the following: (i), (ii) or (iii):

[0784] (i) Component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having two or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of component (A) is 5 parts by mass to 100 parts by mass; (ii) Component (A) comprises a monofunctional epoxy group-containing substance (a2) having one epoxy group in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of component (A) is... (iii) The content of the monofunctional epoxy group-containing substance (a2) is 5 parts by mass to 40 parts by mass; the component (A) comprises the polyfunctional epoxy group-containing substance (a1) and the monofunctional epoxy group-containing substance (a2), wherein in 100 parts by mass of component (A), the content of the polyfunctional epoxy group-containing substance (a1) is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the monofunctional epoxy group-containing substance (a2) is 5 parts by mass to 40 parts by mass.

[0785] [B7] The curable resin composition according to [B2], wherein the core layer of the polymer particles (B-1) contains one or more selected from diene rubbers, (meth)acrylate rubbers and organosiloxane rubbers.

[0786] [B8] A cured product formed by curing any one of the curable resin compositions [B1] to [B7].

[0787] [B9] A fiber-reinforced composite material comprising any one of [B1] to [B7] a curable resin composition and fibers.

[0788] [B10] The fiber-reinforced composite material according to [B9], wherein the fiber is carbon fiber.

[0789] [B11] A wheel comprising the fiber-reinforced composite material described in [B9] or [B10].

[0790] [B12] A wheel disc for a vehicle comprising the fiber-reinforced composite material described in [B9] or [B10].

[0791] Another embodiment of the present invention may be as follows.

[0792] [C1] A curable resin composition comprising components (A), (B), and (C) below, and excluding component (D) below, or further comprising component (D) below.

[0793] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0794] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0795] (C) Component: Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3).

[0796] (D) Ingredient: Curing accelerator,

[0797] Of the 100 parts by weight of component (A), the total content of the bisphenol A epoxy resin, the bisphenol F epoxy resin, and the alicyclic epoxy resin is 5 to 100 parts by weight; the content of component (B) is 1 to 100 parts by weight relative to the 100 parts by weight of component (A); the content of component (C) is 10 to 200 parts by weight relative to the 100 parts by weight of component (A); when component (D) is included, the content of component (D) is 0.1 to 10.0 parts by weight relative to the 100 parts by weight of component (A); and component (A) satisfies any one of the following conditions (i), (ii), or (iii):

[0798] (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass.

[0799] (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass.

[0800] (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass.

[0801] The value Y of this curable resin composition, calculated from the following formula, is 22 to 400.

[0802] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]

[0803] in,

[0804] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0805] The composition (M) comprises the same components (A), (C), and (D) as those in the curable resin composition, and the amounts of components (A), (C), and (D) in the composition (M) are the same as those in the curable resin composition.

[0806] The cured product (M) is a cured product obtained by curing the composition (M) under the following curing conditions.

[0807] Curing conditions: When component (C) is the acid anhydride (Cl), the curing temperature is 175°C and the curing time is 2 hours;

[0808] When component (C) is the aromatic amine (C2), the curing temperature is 175°C and the curing time is 2 hours;

[0809] When component (C) is the alicyclic amine (C3), the curing temperature is 120°C and the curing time is 2 hours.

[0810] [C2] The curable resin composition according to [C1], wherein component (B) contains at least one type of polymer particles selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3).

[0811] The polymer particles (B-1): polymer particles whose shells have epoxy groups, and whose content of epoxy groups in the shells is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shells;

[0812] The polymer particles (B-2): The core layer of the polymer particles is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, wherein the total of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass;

[0813] The polymer particle (B-3): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture. The shell layer of the polymer particle has epoxy groups, and the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer. The monomer mixture contains (b1) 50% to 99.99% by mass of conjugated diene monomers, (b2) 0% to 49.99% by mass of vinyl monomers that can copolymerize with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents. The total mass of (b1) conjugated diene monomers, (b2) vinyl monomers that can copolymerize with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0814] [C3] The curable resin composition according to [C1] or [C2], wherein component (A) further contains a glycidylamine type epoxy resin, wherein the content of the glycidylamine type epoxy resin in 100 parts by weight of component (A) is 29 parts by weight or less.

[0815] [C4] The curable resin composition according to [C2], wherein the core layer of the polymer particles (B-1) contains one or more selected from diene rubbers, (meth)acrylate rubbers and organosiloxane rubbers.

[0816] [C5] A curable resin composition according to any one of [C1] to [C4], wherein the core layer of the (B) component is butadiene rubber and / or butadiene-styrene rubber.

[0817] [C6] A curable resin composition according to any one of [C1] to [C5], wherein the shell layer contains one or more structural units selected from aromatic vinyl units, vinyl cyanide units and (meth)acrylate units.

[0818] [C7] A cured product formed by curing any one of the curable resin compositions [C1] to [C6].

[0819] [C8] A fiber-reinforced composite material comprising any one of [C1] to [C6] a curable resin composition and fibers.

[0820] [C9] The fiber-reinforced composite material according to [C8], wherein the fiber is carbon fiber.

[0821] [C10] A wheel comprising the fiber-reinforced composite material described in [C8] or [C9].

[0822] [C11] A wheel disc for a vehicle comprising the fiber-reinforced composite material described in [C8] or [C9].

[0823] [C12] A high-pressure vessel comprising the fiber-reinforced composite material described in [C8] or [C9].

[0824] Another embodiment of the present invention may be as follows.

[0825] [D1] A curable resin composition,

[0826] It contains the following components: (A), (B), and (C).

[0827] And it does not contain the following ingredient (D) or contains the following ingredient (D),

[0828] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0829] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0830] (C) Composition: Amine-based epoxy curing agent containing amine (c1), wherein the average number of active hydrogens on the amino group of each molecule of the amine (c1) is 1 or 2;

[0831] (D) Ingredient: Curing accelerator,

[0832] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0833] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0834] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0835] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0836] The content of the amine (c1) in component (C) is 5% to 100% by mass in 100% of component (C).

[0837] The curable resin composition

[0838] The value Y calculated by the following formula is between 22 and 400.

[0839] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]

[0840] in,

[0841] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0842] The composition (M) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0843] The contents of components (A), (C), and (D) in the composition (M) are the same as the contents of components (A), (C), and (D) in the curable resin composition.

[0844] The cured product (M) is obtained by curing the composition (M) at a curing temperature of 120°C and a curing time of 2 hours.

[0845] [D2] A two-component or multi-component curable resin composition comprising a first component and a second component, wherein,

[0846] The first component comprises the following component (A),

[0847] The second component comprises component (C) below and does not contain component (D) below, or further comprises component (D) below.

[0848] The curable resin composition further comprises the following component (B):

[0849] (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin;

[0850] (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer;

[0851] (C) Composition: Amine-based epoxy curing agent containing amine (c1), wherein the average number of active hydrogens on the amino group of each molecule of the amine (c1) is 1 or 2;

[0852] (D) Ingredient: Curing accelerator,

[0853] Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight.

[0854] The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A).

[0855] The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A).

[0856] When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A).

[0857] The content of the amine (c1) in component (C) is 5% to 100% by mass in 100% of component (C).

[0858] This two-component or multi-component adhesive

[0859] The value Y calculated by the following formula is between 22 and 400.

[0860] Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]

[0861] in,

[0862] The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained.

[0863] The composition (M) comprises the same components (A), (C), and (D) as those contained in the curable resin composition.

[0864] The contents of components (A), (C), and (D) in the composition (M) are the same as the contents of components (A), (C), and (D) in the curable resin composition.

[0865] The cured product (M) is obtained by curing the composition (M) at a curing temperature of 120°C and a curing time of 2 hours.

[0866] [D3] The curable resin composition according to [D1] or [D2], wherein the number of active hydrogens on the amino group per molecule of component (C) is more than 1.5 and less than 3.8.

[0867] [D4] The curable resin composition according to any one of [D1] to [D3], wherein the (C) component further comprises an alicyclic amine (c2) having an average of 4 active hydrogens on an amino group per molecule, and the content of the amine (c2) in the (C) component is 0.1% to 95.0% by mass in 100% by mass of the (C) component.

[0868] [D5] A curable resin composition according to any one of [D1] to [D4], wherein component (B) comprises at least one polymer particle selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3).

[0869] The polymer particles (B-1): The shell of the polymer particles has epoxy groups, and the content of the epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell.

[0870] The polymer particles (B-2): The core layer of the polymer particles is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture comprises (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agent, wherein the total of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agent is 100% by mass.

[0871] The polymer particle (B-3): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture. The shell layer of the polymer particle has epoxy groups, and the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer. The monomer mixture comprises (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents. The total mass of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass.

[0872] [D6] The curable resin composition according to [D5], wherein the core layer of the polymer particles (B-1) contains one or more selected from diene rubber, (meth)acrylate rubber and organosiloxane rubber.

[0873] [D7] A curable resin composition according to any one of [D1] to [D6], wherein the core layer of the (B) component is butadiene rubber and / or butadiene-styrene rubber.

[0874] [D8] A curable resin composition according to any one of [D1] to [D7], wherein the shell layer contains one or more structural units selected from aromatic vinyl units, vinyl cyanide units and (meth)acrylate units.

[0875] [D9] A cured product formed by curing any one of the curable resin compositions [D1] to [D8].

[0876] [D10] An adhesive comprising any one of [D1] to [D8] a curable resin composition.

[0877] [D11] A laminate comprising: at least two substrates; and an adhesive layer formed by curing the adhesive described in [D10] to bond the at least two substrates.

[0878] [D12] A fiber-reinforced composite material comprising any one of [D1] to [D8] a curable resin composition and fibers.

[0879] [D13] The fiber-reinforced composite material according to [D12], wherein the fiber is carbon fiber.

[0880] [D14] A wheel comprising the fiber-reinforced composite material described in [D12] or [D13].

[0881] [D15] A wheel disc for a vehicle comprising the fiber-reinforced composite material described in [D12] or [D13].

[0882] [D16] A high-pressure vessel comprising the fiber-reinforced composite material described in [D12] or [D13].

[0883] [Example]

[0884] The following describes one embodiment of the present invention in more detail through examples and comparative examples, but the present invention is not limited thereto. One embodiment of the present invention can be implemented by appropriately modifying the following embodiments within the scope of the foregoing and following technical principles. All embodiments implemented by appropriately modifying the following embodiments are included within the technical scope of the present invention. It should be noted that in the following examples, comparative examples, and tables, "parts" and "%" represent parts by mass and percentage by mass, respectively.

[0885] 〔Material〕

[0886] First, the substances used in the examples and comparative examples are as follows.

[0887] <(A)Component>

[0888] A-(1): Alicyclic epoxy resin <3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate> (Daicel's "Celloxide 2021P", epoxy equivalent 130 g / eq)

[0889] A-(2): Bisphenol A type epoxy resin <Bisphenol A type epoxy resin that is liquid at room temperature> ("jER 828" manufactured by Mitsubishi Chemical Corporation, with an epoxy equivalent of 189 g / eq)

[0890] A-(3): Bisphenol F type epoxy resin <Bisphenol F type epoxy resin is liquid at room temperature> ("EPON 863" manufactured by Hexion, with an epoxy equivalent of 170 g / eq)

[0891] A-(4): Other substances containing polyfunctional epoxy groups <1,4-butanediol diglycidyl ether> ("ERISYSGE-21" manufactured by Huntsman, with an epoxy equivalent of 115 g / eq)

[0892] A-(5): Substances containing polyfunctional epoxy groups (a1) <Polypropylene glycol diglycidyl ether> ("PG-207" manufactured by Nippon Steel Chemical & Material Co., Ltd., with an epoxy equivalent of 315 g / eq)

[0893] A-(6): Substances containing polyfunctional epoxy groups (a1) <Bisphenol A type epoxy resin that is solid at room temperature> ("jER 1001" manufactured by Mitsubishi Chemical Corporation, with an epoxy equivalent of 480 g / eq)

[0894] A-(7): Substances containing monofunctional epoxy groups (a2) <o-toluene glycidyl ether> ("ERISYSGE-10" manufactured by Huntsman, with an epoxy equivalent of 182 g / eq)

[0895] A-(8): Glycidylamine type epoxy resin <tetraglycidyldiaminodiphenylmethane> ("ELM-434VL" manufactured by Sumitomo Chemical Co., Ltd., with an epoxy equivalent of 115 g / eq)

[0896] <(B) Ingredients>

[0897] As component (B), polymer particles prepared by the following method were used. It should be noted that, as described later, a dispersion (M-(1) to M-(11)) was prepared by dispersing the prepared component (B) (polymer particles) into component (A) (A-(1) or A-(2)), and the dispersion was used.

[0898] 1. Formation of the core layer

[0899] Manufacturing Example 1-1: Preparation of Polybutadiene Rubber Latex (R-1)

[0900] In a 100L pressure polymerizer, 200 parts by weight of deionized water, 0.03 parts by weight of tripotassium phosphate, 0.25 parts by weight of potassium dihydrogen phosphate, 0.002 parts by weight of disodium ethylenediaminetetraacetate (EDTA), 0.001 parts by weight of ferrous sulfate hexahydrate (FE), and 1.5 parts by weight of sodium dodecylbenzenesulfonate (SDS) as an emulsifier were added. Next, while stirring the added raw materials, the gas inside the pressure polymerizer was purged with nitrogen to completely remove oxygen. Then, 100 parts by weight of butadiene (BD) was added to the pressure polymerizer,...

Claims

1. A curable resin composition, It contains component (A) and component (B) below, and does not contain component (D) below, or also contains component (D) below. (A) Components: Substances containing epoxy groups, which include one or more selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin and alicyclic epoxy resin; (B) Composition: Polymer particles having a core-shell structure comprising a core layer and a shell layer; (D) Ingredient: Curing accelerator, Furthermore, the curable resin composition satisfies at least one of the following conditions (1) to (3): (1) It also contains the following components (C): acid anhydride (C1), aromatic amine (C2) or alicyclic amine (C3). Of component (A), the total content of bisphenol A epoxy resin, bisphenol F epoxy resin, and alicyclic epoxy resin in 100 parts by weight is 60 to 100 parts by weight. The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A). The content of component (C) is 5 to 200 parts by mass relative to 100 parts by mass of component (A). When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A). The value X of the curable resin composition, calculated by the following formula, is 1.05 to 5.50 when component (C) is the acid anhydride (C1), and 1.30 to 9.00 when component (C) is the aromatic amine (C2) or the alicyclic amine (C3). Calculation formula: X = {[273 + Tmin(M)] / [273 + Tmin(Meq)]} × [E'(Meq)] / [E'(M)]; (2) It also contains the following component (C): Epoxy curing agent, which contains one or more selected from acid anhydrides (C1), aromatic amines (C2), and alicyclic amines (C3). Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight. The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A). The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A). When component (D) is included, the content of component (D) is 0.1 to 10.0 parts by mass relative to 100 parts by mass of component (A). The (A) component satisfies any one of the following conditions (i), (ii) or (iii): (i) The (A) component comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the (A) component is 5 parts by mass to 100 parts by mass. (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, and the content of the monofunctional epoxy group containing substance (a2) in 100 parts by mass of component (A) is 5 parts by mass to 95 parts by mass. (iii) Component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 95 parts by mass. The value Y of the curable resin composition, calculated by the following formula, is 22 to 400. Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; (3) It also contains the following component (C): amine-based epoxy curing agent containing an amine (C4), wherein the average number of active hydrogen atoms on the amino group of the amine (C4) per molecule is 1 or 2. Of component (A), the total content of the bisphenol A type epoxy resin, the bisphenol F type epoxy resin, and the alicyclic epoxy resin in 100 parts by weight is 5 parts by weight to 100 parts by weight. The content of component (B) is 1 to 100 parts by mass relative to 100 parts by mass of component (A). The content of component (C) is 10 to 200 parts by mass relative to 100 parts by mass of component (A). When component (D) is included, the content of component (D) is 0.1 to 20.0 parts by mass relative to 100 parts by mass of component (A). The content of the amine (C4) in component (C) is 5% to 100% by mass in 100% of component (C). The value Y of the curable resin composition, calculated by the following formula, is 22 to 400. Calculation formula: Y = [273 + Tmin(M)] / [E'(M)]; in, In the formulas for calculating the value X and the value Y, The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (M) of composition (M) as a sample under tensile mode and a frequency of 1 Hz, is denoted as Ttg(M) (°C). E'(M) represents the minimum value of the storage modulus (E') of the cured product (M) in the temperature range of [Ttg(M) (°C)] to [Ttg(M) + 25 (°C)]. Tmin(M) (°C) is the temperature (°C) at which the value of E'(M) is obtained. Furthermore, the composition (M) contains components related to the cured product... The resin composition contains the same components (A), (C), and (D) as components (D), and the composition (M) contains the same amounts of components (A), (C), and (D) as those in the curable resin composition. The cured product (M) is obtained by curing the composition (M) and exhibits a degree of cure of 98% or higher as measured by DSC. In the formula for calculating the value X, The temperature at which the loss tangent is maximized, determined by dynamic viscoelasticity measurement using the cured product (Meq) of the composition (Meq) as the sample and under tensile mode and a frequency of 1 Hz, is defined as Ttg(Meq) (°C). E'(Meq) represents the minimum storage modulus (E') of the cured product (Meq) in the temperature range of [Ttg(Meq) (°C)] to [Ttg(Meq) + 25 (°C)]. Tmin(Meq) (°C) is the temperature at which E'(Meq) is obtained. The temperature (°C) at which the value is determined, and the composition (Meq) contains the same components (A), (C), and (D) as those contained in the curing resin composition, wherein the content of each of components (A) and (D) in the composition (Meq) is the same as the content of each of components (A) and (D) in the curing resin composition, and the component (C) in the composition (Meq) is... When the acid anhydride (c1) is present, the content of component (C) in the composition (Meq) is such that the molar amount of the acid anhydride group in component (C) relative to the molar amount of the epoxy group in component (A) contained in the composition (Meq), i.e., the ratio of the molar amount of the acid anhydride group in component (C) / the molar amount of the epoxy group in component (A) is 1. When component (C) in the composition (Meq) is the aromatic amine (c2) or the alicyclic amine (c3), the content of component (C) in the composition (Meq) is such that the content of component (C ... The content of component (C) in the composition (Meq) is such that the molar amount of active hydrogen of the amine in component (C) is relative to the molar amount of epoxy group in component (A) contained in the composition (Meq), that is, the ratio of the molar amount of active hydrogen of the amine in component (C) / the molar amount of epoxy group in component (A) is 1. The cured product (Meq) is a cured product obtained by curing the composition (Meq) and exhibiting a degree of curing of 98% or more as measured by DSC.

2. The curable resin composition according to claim 1, wherein, Component (B) comprises at least one type of polymer particles selected from polymer particles (B-1), polymer particles (B-2), and polymer particles (B-3) described below. Polymer particles (B-1): The shell of the polymer particles has epoxy groups, and the content of the epoxy groups in the shell is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell. Polymer Particles (B-2): The core layer of these polymer particles is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture comprises (b1) 50.00% to 99.99% by mass of a conjugated diene monomer, (b2) 0.00% to 49.99% by mass of a vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) 0.01% to 3.00% by mass of a chain transfer agent, wherein the total of (b1) the conjugated diene monomer, (b2) the vinyl monomer capable of copolymerizing with the conjugated diene monomer, and (b3) the chain transfer agent is 100% by mass. Polymer Particle (B-3): The core layer of the polymer particle is a diene rubber obtained by polymerizing a monomer mixture, wherein the monomer mixture comprises (b1) 50.00% to 99.99% by mass of conjugated diene monomers, (b2) 0.00% to 49.99% by mass of vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) 0.01% to 3.00% by mass of chain transfer agents, wherein the total mass of (b1) conjugated diene monomers, (b2) vinyl monomers capable of copolymerizing with the conjugated diene monomers, and (b3) chain transfer agents is 100% by mass, and the shell layer of the polymer particle has epoxy groups, wherein the content of the epoxy groups in the shell layer is 0.2 mmol / g to 5.0 mmol / g relative to the total mass of the shell layer.

3. The curable resin composition according to claim 1 or 2, wherein, The core layer of component (B) is butadiene rubber and / or butadiene-styrene rubber.

4. The curable resin composition according to any one of claims 1 to 3, wherein, The shell contains one or more structural units selected from aromatic vinyl units, vinyl cyanide units, and (meth)acrylate units.

5. The curable resin composition according to any one of claims 1 to 4, wherein, If the curable resin composition satisfies the condition (1), The component (C) is the acid anhydride (c1), and the content of the component (C) in the curable resin composition is such that the molar amount of the acid anhydride group in the component (C) relative to the molar amount of the epoxy group in the component (A) contained in the curable resin composition, i.e., the ratio of the molar amount of the acid anhydride group in the component (C) / the molar amount of the epoxy group in the component (A), is 0.35 to 0.

87.

6. The curable resin composition according to any one of claims 1 to 4, wherein, If the curable resin composition satisfies the condition (1), The component (C) is the aromatic amine (C2) or the alicyclic amine (C3), and the content of the component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in the component (C) relative to the molar amount of epoxy groups in the component (A) contained in the curable resin composition, i.e. the molar amount of active hydrogen of the amine in the component (C) / the molar amount of epoxy groups in the component (A), is 0.67 to 0.87 or 1.10 to 2.

40.

7. The curable resin composition according to any one of claims 1 to 4, wherein, If the curable resin composition satisfies the condition (1), The component (C) is the aromatic amine (C2) or the alicyclic amine (C3), and the content of the component (C) in the curable resin composition is such that the molar amount of active hydrogen of the amine in the component (C) relative to the molar amount of epoxy groups in the component (A) contained in the curable resin composition, that is, the ratio of the molar amount of active hydrogen of the amine in the component (C) / the molar amount of epoxy groups in the component (A) is 0.67 to 0.

87.

8. The curable resin composition according to any one of claims 1 to 7, wherein, If the curable resin composition satisfies the conditions of (1) and / or (2), The component (A) further contains glycidylamine type epoxy resin, and the content of glycidylamine type epoxy resin in 100 parts by weight of component (A) is less than 29 parts by weight.

9. The curable resin composition according to any one of claims 1 to 4, wherein, If the curable resin composition satisfies the condition (1), The (A) component satisfies any one of the following conditions (i), (ii) or (iii): (i) The component (A) comprises a polyfunctional epoxy group-containing substance (a1) having an epoxy equivalent of 300 g / eq or more and less than 3000 g / eq and having 2 or more epoxy groups in one molecule, wherein the content of the polyfunctional epoxy group-containing substance (a1) in 100 parts by mass of the component (A) is 5 parts by mass to 100 parts by mass. (ii) The component (A) comprises a monofunctional epoxy group containing a substance (a2) having one epoxy group in one molecule, wherein the content of the monofunctional epoxy group containing substance (a2) is 5 to 40 parts by mass in 100 parts by mass of the component (A). (iii) The component (A) comprises the substance (a1) containing a polyfunctional epoxy group and the substance (a2) containing a monofunctional epoxy group, wherein in 100 parts by mass of the component (A), the content of the substance (a1) containing a polyfunctional epoxy group is 5 parts by mass to 95 parts by mass, and in 100 parts by mass of the component (A), the content of the substance (a2) containing a monofunctional epoxy group is 5 parts by mass to 40 parts by mass.

10. The curable resin composition according to any one of claims 1 to 4, wherein, If the curable resin composition satisfies the condition described in (3), The number of active hydrogen atoms on the amino group in each molecule of component (C) is more than 1.5 and less than 3.

8.

11. A cured product formed by curing the curable resin composition according to any one of claims 1 to 10.

12. A laminate comprising: At least two substrates; and An adhesive layer formed by bonding the at least two substrates together and curing an adhesive containing a curable resin composition according to any one of claims 1 to 10.

13. A fiber-reinforced composite material comprising: The curable resin composition according to any one of claims 1 to 10, and fiber.

14. A wheel comprising the fiber-reinforced composite material of claim 13.

15. A high-pressure vessel comprising the fiber-reinforced composite material of claim 13.

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