JP6767758B2 - Polymer fine particle-containing curable resin composition with improved storage stability and adhesiveness - Google Patents

Description

The present invention relates to a curable resin composition containing an epoxy resin as a main component, which is excellent in storage stability and adhesiveness.

The cured product of epoxy resin is excellent in many points such as dimensional stability, mechanical strength, electrical insulation property, heat resistance, water resistance, and chemical resistance. However, the cured product of the epoxy resin has low fracture toughness and may exhibit a very brittle property, and such a property is often a problem in a wide range of applications.

In Patent Document 1 and Patent Document 2, the toughness and impact resistance of the obtained cured product are improved by dispersing the polymer fine particles in a curable resin composition containing a curable resin such as an epoxy resin as a main component. The technology is disclosed.

Adhesives using epoxy resin compositions having toughness and impact resistance are used as structural adhesives for vehicles, and the impact resistance peeling adhesive strength described in ISO11343 is emphasized.

Patent Document 3 discloses a technique of dehydrating water in an epoxy resin composition using calcium oxide to suppress foaming of the composition during heat curing.

WO2009-034966 Pamphlet Japanese Unexamined Patent Publication No. 2014-141604 Japanese Unexamined Patent Publication No. 2000-1989906

However, the epoxy resin composition containing polymer fine particles having a core-shell structure and calcium oxide which has not been surface-treated has problems of T-shaped peeling adhesiveness and impact-resistant peeling adhesiveness, and the viscosity of the composition after storage is high. It turns out that there is a challenge of rising.

In general, structural adhesives for vehicles are often used in a one-component type, and it has been an extremely important issue to achieve both T-shaped peeling adhesiveness, impact-resistant peeling adhesiveness, and storage stability.

The present invention has been made in view of the above circumstances, and the present invention is a curable resin composition containing an epoxy resin as a main component, which has excellent storage stability and the adhesiveness of the obtained cured product. It is an object of the present invention to provide a curable resin composition having excellent impact resistance and peeling adhesiveness.

As a result of diligent studies to solve such a problem, the present inventor has found that a curable resin composition containing an epoxy resin (A), polymer fine particles (B) having a core-shell structure, and calcium oxide (C). The present invention has been completed by finding that the above-mentioned problems can be solved by using the surface-treated calcium oxide as the component (C).

1) That is, in the present invention, with respect to 100 parts by mass of the epoxy resin (A), 1 to 100 parts by mass of the polymer fine particles (B) having a core-shell structure and 0.1 to 10 parts by mass of the surface-treated calcium oxide (C). The present invention relates to a curable resin composition containing.

2) Furthermore, the surface treatment agent for the component (C) is preferably a fatty acid.

3) Further, it is preferable that the content of untreated calcium oxide is 20 parts by mass or less with respect to 100 parts by mass of the component (C).

4) Further, it is more preferable that 100 parts by mass of the component (C) does not substantially contain surface-untreated calcium oxide.

5) Further, it is preferable to further contain 1 to 80 parts by mass of the epoxy curing agent (D) with respect to 100 parts by mass of the component (A).

6) Further, it is preferable to further contain 0.1 to 10 parts by mass of the curing accelerator (E) with respect to 100 parts by mass of the component (A).

7) Further, the component (B) preferably has one or more core layers selected from the group consisting of a diene rubber, a (meth) acrylate rubber, and a polysiloxane rubber.

8) Further, it is more preferable that the diene rubber is a butadiene rubber and / or a butadiene-styrene rubber.

9) Further, the component (B) is a shell layer formed by graft-polymerizing one or more monomer components selected from the group consisting of an aromatic vinyl monomer, a vinyl cyan monomer, and a (meth) acrylate monomer onto a core layer. It is more preferable to have.

10) Further, it is more preferable that the component (B) has a shell layer formed by graft-polymerizing a monomer component having an epoxy group onto the core layer.

11) Further, the content of the epoxy group in the component (B) is preferably 0.01 to 0.8 mmol / g.

12) Further, it is preferable that the component (B) is dispersed in the state of primary particles in the curable resin composition.
13) The curable resin composition preferably contains 1 to 100 parts by mass of surface-treated calcium carbonate with respect to 100 parts by mass of the component (A).

14) It is preferably a cured product obtained by curing any of the above curable resin compositions.

15) A one-component curable resin composition is preferable.

16) A structural adhesive is preferred.

17) More preferably, it is a structural adhesive for vehicles.

The curable resin composition of the present invention has excellent storage stability, and can improve the adhesiveness and impact-resistant peeling adhesiveness of the obtained cured product.

Hereinafter, the curable resin composition of the present invention will be described in detail.

The curable resin composition of the present invention comprises 100 parts by mass of an epoxy resin (A), 1 to 100 parts by mass of polymer fine particles (B) having a core-shell structure, and 0.1 to 10 parts by mass of surface-treated calcium oxide (C). Part, contains.

<Epoxy resin (A)>
The epoxy resin (A) is used as the main component of the curable resin composition of the present invention.

As the epoxy resin, various hard epoxy resins other than the rubber-modified epoxy resin and the urethane-modified epoxy resin described later can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol AD type epoxy. Resin, bisphenol S type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, novolak type epoxy resin, bisphenol A propylene oxide adduct glycidyl ether type epoxy resin, hydrogenated bisphenol A (or F) type epoxy resin, Fluorinated epoxy resin, flame-retardant epoxy resin such as tetrabromobisphenol A glycidyl ether, p-oxybenzoate glycidyl ether ester type epoxy resin, m-aminophenol type epoxy resin, diaminodiphenylmethane-based epoxy resin, various alicyclic types 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, aliphatic Includes diglycidyl esters of polybasic acids, glycidyl ethers of divalent or higher polyvalent aliphatic alcohols such as glycerin, epoxies of unsaturated polymers such as chelate-modified epoxy resins, hidden-in type epoxies, and petroleum resins Examples thereof include aminoglycidyl ether resins and epoxy compounds obtained by adding bisphenol A (or F) or polybasic acids to the above epoxy resin, but the present invention is not limited to these and is generally used. Epoxy resins that have been used can be used.

More specific examples of the polyalkylene glycol diglycidyl ether include polyethylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether. More specific examples of the glycol diglycidyl ether include neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, cyclohexanedimethanol diglycidyl ether and the like. Be done. More specific examples of the aliphatic polybasic acid diglycidyl ester include dimer acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, and maleic acid diglycidyl ester. More specifically, the glycidyl ether of the divalent or higher polyvalent aliphatic alcohol includes trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, castor oil-modified polyglycidyl ether, propoxylated glycerin triglycidyl ether, and sorbitol. Examples include polyglycidyl ether. Examples of the epoxy compound obtained by adding a polybasic acid or the like to an epoxy resin include a dimer of a tall oil fatty acid (dimeric acid) and a bisphenol A type epoxy as described in WO2010-098950. Examples include an addition reaction product with a resin. These epoxy resins may be used alone or in combination of two or more.

The polyalkylene glycol diglycidyl ether, the glycol diglycidyl ether, the diglycidyl ester of the aliphatic polybasic acid, and the glycidyl ether of the divalent or higher polyvalent aliphatic alcohol are epoxy resins having a relatively low viscosity. When used in combination with other epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin, it functions as a reactive diluent and can improve the balance between the viscosity of the composition and the physical properties of the cured product. The content of the epoxy resin that functions as the reactive diluent is preferably 0.5 to 20% by mass, more preferably 1 to 10% by mass, and even more preferably 2 to 5% by mass in the epoxy resin (A) component. ..

The chelate-modified epoxy resin is a reaction product of an epoxy resin and a compound containing a chelate functional group (chelate ligand), and was added to the curable resin composition of the present invention and used as an adhesive for vehicles. If so, the adhesion to the surface of a metal substrate contaminated with an oily substance can be improved. The chelate functional group is a functional group of a compound having a plurality of coordination positions capable of coordinating to a metal ion in the molecule, and is, for example, a phosphorus-containing acid group (for example, -PO (OH) ₂ ) or a carboxylic acid group (-). CO ₂ H), sulfur-containing acid groups (eg, −SO ₃ H), amino groups and hydroxyl groups (particularly, hydroxyl groups adjacent to each other in the aromatic ring) and the like. Examples of the chelating ligand include ethylenediamine, bipyridine, ethylenediaminetetraacetic acid, phenanthroline, porphyrin, crown ether, and the like. Examples of commercially available chelate-modified epoxy resins include ADEKA ADEKA Resin EP-49-10N.

The amount of the chelate-modified epoxy resin used in the component (A) is preferably 0.1 to 10% by mass, more preferably 0.5 to 3% by mass.

Among these epoxy resins, those having at least two epoxy groups in one molecule are preferable because they have high reactivity during curing and the cured product easily forms a three-dimensional network.

Among the above-mentioned epoxy resins, bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferable because the obtained cured product has a high elastic modulus, excellent heat resistance and adhesiveness, and is relatively inexpensive. Resin is particularly preferred.

Among various epoxy resins, an epoxy resin having an epoxy equivalent of less than 220 is preferable because of its high elastic modulus and heat resistance of the obtained cured product, and an epoxy equivalent of 90 or more and less than 210 is more preferable, and 150 or more and less than 200. Is more preferable.

In particular, bisphenol A type epoxy resin and bisphenol F type epoxy resin having an epoxy equivalent of less than 220 are preferable because they are liquid at room temperature and the obtained curable resin composition is easy to handle.

It is obtained by adding a bisphenol A type epoxy resin or a bisphenol F type epoxy resin having an epoxy equivalent of 220 or more and less than 5000 to the component (A) in a range of preferably 40% by mass or less, more preferably 20% by mass or less. The cured product is preferable because it has excellent impact resistance.

<Polymer fine particles (B)>
The curable resin composition of the present invention uses 1 to 100 parts by mass of polymer fine particles (B) having a core-shell structure with respect to 100 parts by mass of the component (A). Due to the toughness improving effect of the component (B), the obtained cured product is excellent in toughness and impact resistance peeling adhesiveness.

From the balance between the ease of handling of the obtained curable resin composition and the effect of improving the toughness of the obtained cured product, 1 to 100 parts by mass of the component (B) is preferable with respect to 100 parts by mass of the component (A), and 2 to 2 70 parts by mass is more preferable, 3 to 50 parts by mass is further preferable, and 4 to 20 parts by mass is particularly preferable.

When an epoxy group is contained in the component (B), the content of the epoxy group in the component (B) is set to 0 from the viewpoint of achieving both impact resistance and peeling adhesion of the obtained cured product and storage stability of the composition. It is preferably 01 to 0.8 mmol / g, more preferably 0.02 to 0.6 mmol / g, further preferably 0.04 to 0.4 mmol / g, and particularly preferably 0.05 to 0.2 mmol / g. If the content of the epoxy group of the component (B) is less than 0.01 mmol / g, the impact-resistant peeling adhesiveness of the obtained cured product tends to decrease. If it is more than 0.8 mmol / g, the viscosity of the composition after storage tends to increase.

The particle size of the polymer fine particles is not particularly limited, but in consideration of industrial productivity, the volume average particle size (Mv) is preferably 10 to 2000 nm, more preferably 30 to 600 nm, further preferably 50 to 400 nm, and even more preferably 100 to 200 nm. Is particularly preferable. The volume average particle diameter (Mv) of the polymer particles can be measured using Microtrack UPA150 (manufactured by Nikkiso Co., Ltd.).

The curable resin obtained by the component (B) having a half-value width of 0.5 times or more and 1 times or less of the number average particle size in the number distribution of the particle size in the composition of the present invention. It is preferable because the composition has a low viscosity and is easy to handle.

From the viewpoint of easily realizing the above-mentioned specific particle size distribution, it is preferable that two or more maximum values exist in the number distribution of the particle size of the component (B), and the maximum value is obtained from the viewpoint of labor and cost during manufacturing. It is more preferable that there are 2 to 3 values, and it is further preferable that there are 2 maximum values. In particular, it is preferable to contain 10 to 90% by mass of polymer fine particles having a volume average particle diameter of 10 nm or more and less than 150 nm, and 90 to 10% by mass of polymer fine particles having a volume average particle diameter of 150 nm or more and 2000 nm or less.

The component (B) is preferably dispersed in the state of primary particles in the curable resin composition. In the present invention, "polymer fine particles are dispersed in the state of primary particles in a curable resin composition" (hereinafter, also referred to as primary dispersion) means that the polymer fine particles are substantially independent (contact) with each other. It means that it is dispersed (without), and the dispersed state means that, for example, a part of the curable resin composition is dissolved in a solvent such as methyl ethyl ketone, and this is dissolved by a particle size measuring device or the like by laser light scattering. It can be confirmed by measuring the particle size.

The value of the volume average particle diameter (Mv) / number average particle diameter (Mn) measured by the particle diameter measurement is not particularly limited, but is preferably 3 or less, more preferably 2.5 or less, still more preferably 2 or less. , 1.5 or less is particularly preferable. If the volume average particle diameter (Mv) / number average particle diameter (Mn) is 3 or less, it is considered that the particles are well dispersed. On the contrary, the curable resin composition having a particle size distribution exceeding 3 may have low physical properties such as impact resistance and adhesiveness of the obtained cured product.

The volume average particle diameter (Mv) / number average particle diameter (Mn) can be determined by measuring using Microtrac UPA (manufactured by Nikkiso Co., Ltd.) and dividing Mv by Mn.

Further, "stable dispersion" of the polymer fine particles means that the polymer fine particles do not aggregate, separate, or settle in the continuous layer, and are constantly under normal conditions for a long period of time. It means that the polymer fine particles are dispersed, the distribution of the polymer fine particles in the continuous layer does not change substantially, and the viscosity of these compositions is lowered by heating them within a non-hazardous range. It is preferable that "stable dispersion" can be maintained even with stirring.

The component (B) may be used alone or in combination of two or more.

The structure of the polymer fine particles is not particularly limited, but it is preferable to have a core-shell structure of two or more layers. It is also possible to have a structure of three or more layers composed of an intermediate layer that covers the core layer and a shell layer that further covers the intermediate layer.

Hereinafter, each layer will be specifically described.
≪Core layer≫
The core layer is preferably an elastic core layer having rubber properties in order to increase the toughness of the cured product of the curable resin composition of the present invention. In order to have properties as a rubber, the elastic core layer of the present invention preferably has a gel content of 60% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass or more. It is preferably 95% by mass or more, and particularly preferably 95% by mass or more. The gel content referred to in the present specification refers to the case where 0.5 g of crumb obtained by coagulation and drying is immersed in 100 g of toluene, allowed to stand at 23 ° C. for 24 hours, and then the insoluble and soluble components are separated. , Means the ratio of insoluble matter to the total amount of insoluble matter and soluble matter.

As a polymer capable of forming an elastic core layer having rubber properties, at least one monomer (first monomer) selected from natural rubber, a diene-based monomer (conjugated diene-based monomer) and a (meth) acrylate-based monomer) 50 to 100% by mass, and 0 to 50% by mass of another copolymerizable vinyl-based monomer (second monomer), a polysiloxane-based rubber elastic body, or a combination thereof. Things can be mentioned. The diene system has a high effect of improving the toughness and impact resistance peeling adhesiveness of the obtained cured product, and a low affinity with the matrix resin makes it difficult for the viscosity to increase with time due to swelling of the core layer. A diene-based rubber using a monomer is preferable. A (meth) acrylate-based rubber is preferable because a wide range of polymer designs can be made by combining various monomers. Further, when it is intended to improve the impact resistance at a low temperature without lowering the heat resistance of the cured product, the elastic core layer is preferably a polysiloxane-based rubber elastic body. In the present invention, (meth) acrylate means acrylate and / or methacrylate.

Examples of the monomer (conjugated diene-based monomer) constituting the diene-based rubber used for the elastic core layer include 1,3-butadiene, isoprene, 2-chloro-1,3-butadiene, and 2-methyl-1,3-butadiene. And so on. These diene-based monomers may be used alone or in combination of two or more.

1,3-butadiene is used because it has a high effect of improving toughness and impact resistance and adhesiveness, and because it has a low affinity with the matrix resin, it is unlikely that the viscosity will increase over time due to swelling of the core layer. Butadiene rubber or butadiene-styrene rubber, which is a copolymer of 1,3-butadiene and styrene, is preferable, and butadiene rubber is more preferable. Further, butadiene-styrene rubber is more preferable because it can enhance the transparency of the cured product obtained by adjusting the refractive index.

Examples of the monomer constituting the (meth) acrylate-based rubber used for the elastic core layer include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and octyl (meth). Alkyl (meth) acrylates such as meta) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, and behenyl (meth) acrylate; aromatic ring-containing (meth) such as phenoxyethyl (meth) acrylate and benzyl (meth) acrylate. Acrylate; hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; glycidyl (meth) acrylates such as glycidyl (meth) acrylate and glycidylalkyl (meth) acrylate; Alkoxyalkyl (meth) acrylates; Allylalkyl (meth) acrylates such as allyl (meth) acrylate and allylalkyl (meth) acrylate; Monoethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene Examples thereof include polyfunctional (meth) acrylates such as glycol di (meth) acrylate. These (meth) acrylate-based monomers may be used alone or in combination of two or more. Particularly preferred are ethyl (meth) acrylate, butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.

Examples of the vinyl-based monomer (second monomer) copolymerizable with the first monomer include vinyl allenes such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; vinylcarboxylic acids such as acryloacid and methacrylic acid. Vinyl cyanides such as acrylonitrile and methacrylonitrile; vinyl halides such as vinyl chloride, vinyl bromide and chloroprene; vinyl acetate; alkens such as ethylene, propylene, butylene and isobutylene; diallylphthalate and triallyl cyanurate, Examples thereof include polyfunctional monomers such as triallyl isocyanurate and divinylbenzene. These vinyl-based monomers may be used alone or in combination of two or more. Styrene is particularly preferable.

The copolymerizable vinyl-based monomer can be contained in the range of 0 to 50% by mass, preferably 0 to 30% by mass, and more preferably 0 to 10% by mass of the core layer.

Examples of the polysiloxane-based rubber elastic body that can form the elastic core layer include alkyl or aryl such as dimethylsilyloxy, diethylsilyloxy, methylphenylsilyloxy, diphenylsilyloxy, and dimethylsilyloxy-diphenylsilyloxy. Polysiloxane-based polymers composed of alkyl or aryl1-substituted silyloxy units, such as polysiloxane-based polymers composed of disubstituted silyloxy units and organohydrogensilyloxys in which part of the side chain alkyl is substituted with hydrogen atoms. Examples include polymers. These polysiloxane-based polymers may be used alone or in combination of two or more. Of these, dimethylsilyloxy, methylphenylsilyloxy, and dimethylsilyloxy-diphenylsilyloxy are preferable in imparting heat resistance to the cured product, and dimethylsilyloxy is most preferable because it is easily available and economical.

In the embodiment in which the elastic core layer is formed of a polysiloxane-based rubber elastic body, the polysiloxane-based polymer moiety is 80% by mass or more (more preferably) with the entire elastic body as 100% by mass so as not to impair the heat resistance of the cured product. Is preferably contained in an amount of 90% by mass or more).

From the viewpoint of maintaining the dispersion stability of the polymer fine particles in the curable resin composition, it is preferable that the core layer has a crosslinked structure introduced into a polymer component obtained by polymerizing the above-mentioned monomer or a polysiloxane-based polymer component. .. As a method for introducing the crosslinked structure, a generally used method can be adopted. For example, as a method of introducing a crosslinked structure into a polymer component obtained by polymerizing the above-mentioned monomer, a method of adding a crosslinked monomer such as a polyfunctional monomer or a mercapto group-containing compound to the polymer component and then polymerizing may be mentioned. .. Further, as a method of introducing a crosslinked structure into the polysiloxane-based polymer, a method of partially using a polyfunctional alkoxysilane compound at the time of polymerization or a method of using a reactive group such as a vinyl-reactive group or a mercapto group as a polysiloxane-based polymer. After that, a vinyl polymerizable monomer or an organic peroxide is added to cause a radical reaction, or a crosslinkable monomer such as a polyfunctional monomer or a mercapto group-containing compound is added to the polysiloxane polymer. Then, a method of polymerization and the like can be mentioned.

The polyfunctional monomer does not include a conjugated diene-based monomer such as butadiene, and allylalkyl (meth) acrylates such as allyl (meth) acrylate and allylalkyl (meth) acrylate; allyloxyalkyl (meth) acrylates; (Poly) ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate and other (meth) acrylics Polyfunctional (meth) acrylates having two or more groups; diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene and the like can be mentioned. Particularly preferred are allyl methacrylate, triallyl isocyanurate, butanediol di (meth) acrylate, and divinylbenzene.

In the present invention, the glass transition temperature of the core layer (hereinafter, may be simply referred to as “Tg”) is preferably 0 ° C. or lower, preferably −20 ° C. or lower, in order to increase the toughness of the obtained cured product. More preferably, it is more preferably −40 ° C. or lower, and particularly preferably −60 ° C. or lower.

On the other hand, when it is desired to suppress a decrease in the elastic modulus (rigidity) of the obtained cured product, the Tg of the core layer is preferably larger than 0 ° C, more preferably 20 ° C or higher, and more preferably 50 ° C or higher. It is more preferably 80 ° C. or higher, and most preferably 120 ° C. or higher.

As a polymer capable of forming a core layer having a Tg larger than 0 ° C. and suppressing a decrease in rigidity of the obtained cured product, 50 to 100 mass by mass of at least one monomer having a Tg larger than 0 ° C. of the homopolymer. % (More preferably 65 to 99% by mass), and 0 to 50% by mass (more preferably 1 to 35% by mass) of at least one monomer having a Tg of the homopolymer lower than 0 ° C. Polymers can be mentioned.

Even when the Tg of the core layer is larger than 0 ° C., it is preferable that the core layer has a crosslinked structure introduced. Examples of the method for introducing the crosslinked structure include the above methods.

Examples of the monomers having a Tg higher than 0 ° C. of the homopolymer include those containing one or more of the following monomers, but are not limited thereto. For example, unsubstituted vinyl aromatic compounds such as styrene and 2-vinylnaphthalene; vinyl-substituted aromatic compounds such as α-methylstyrene; 3-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, 2, Ring-alkylated vinyl aromatic compounds such as 5-dimethylstyrene, 3,5-dimethylstyrene, 2,4,6-trimethylstyrene; Ring-alkenylated vinyl aromatic compounds such as 4-methoxystyrene and 4-ethoxystyrene. Vinyl halogenated vinyl aromatic compounds such as 2-chlorostyrene and 3-chlorostyrene; ring ester-substituted vinyl aromatic compounds such as 4-acetoxystyrene; ring hydroxylated vinyl aromatic compounds such as 4-humanloxystyrene; Classes; vinyl esters such as vinyl benzoate and vinyl cyclohexanoate; vinyl halides such as vinyl chloride; aromatic monomers such as acenaphthalene and inden; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate and isopropyl methacrylate; phenyl Aromatic methacrylates such as methacrylate; methacrylates such as isobornyl methacrylate and trimethylsilyl methacrylate; methacrylic monomers containing methacrylic acid derivatives such as methacrylonitrile; certain acrylic acid esters such as isobornyl acrylate and tert-butyl acrylate; Acrylic monomers containing acrylic acid derivatives such as acrylonitrile can be mentioned. Further, the Tg of acrylamide, isopropylacrylamide, N-vinylpyrrolidone, isobornyl methacrylate, dicyclopentanyl methacrylate, 2-methyl-2-adamantyl methacrylate, 1-adamantyl acrylate, 1-adamantyl methacrylate, etc. is 120 ° C. or higher. Monomer can be mentioned.

The volume average particle size of the core layer is preferably 0.03 to 2 μm, more preferably 0.05 to 1 μm. It is often difficult to stably obtain a particle having a volume average particle diameter of less than 0.03 μm, and if it exceeds 2 μm, the heat resistance and impact resistance of the final molded product may deteriorate. The volume average particle size can be measured using Microtrack UPA150 (manufactured by Nikkiso Co., Ltd.).

The core layer is preferably 40 to 97% by mass, more preferably 60 to 95% by mass, further preferably 70 to 93% by mass, and particularly preferably 80 to 90% by mass, with the entire polymer particles as 100% by mass. If the core layer is less than 40% by mass, the effect of improving the toughness of the cured product may decrease. If the core layer is larger than 97% by mass, the polymer fine particles tend to aggregate, and the curable resin composition becomes highly viscous and may be difficult to handle.

In the present invention, the core layer often has a single-layer structure, but may have a multi-layer structure composed of layers having rubber elasticity. Further, when the core layer has a multilayer structure, the polymer composition of each layer may be different within the scope of the above disclosure.

≪Middle layer≫
In the present invention, an intermediate layer may be formed if necessary. In particular, the following rubber surface crosslinked layer may be formed as an intermediate layer. From the viewpoint of improving the toughness of the obtained cured product and improving the impact resistance peeling adhesiveness, it is preferable that the intermediate layer is not contained, and in particular, the following rubber surface crosslinked layer is not contained.

When the intermediate layer is present, the ratio of the intermediate layer to 100 parts by mass of the core layer is preferably 0.1 to 30 parts by mass, more preferably 0.2 to 20 parts by mass, still more preferably 0.5 to 10 parts by mass. , 1 to 5 parts by mass is particularly preferable.

The rubber surface crosslinked layer is polymerized with a rubber surface crosslinked layer component composed of 30 to 100% by mass of a polyfunctional monomer having two or more radically polymerizable double bonds in the same molecule and 0 to 70% by mass of other vinyl monomers. It is composed of an intermediate layer polymer, which has an effect of lowering the viscosity of the curable resin composition of the present invention and an effect of improving the dispersibility of the polymer fine particles (B) in the component (A). It also has the effect of increasing the crosslink density of the core layer and increasing the graft efficiency of the shell layer.

Specific examples of the polyfunctional monomer include the same monomers as the above-mentioned polyfunctional monomer, but allyl methacrylate and triallyl isocyanurate are preferable.

≪Shell layer≫
The shell layer existing on the outermost side of the polymer fine particles is obtained by polymerizing a monomer for forming a shell, but it improves the compatibility between the polymer fine particles (B) component and the (A) component, and the curable resin composition of the present invention. It consists of a shell polymer that plays a role in enabling the polymer fine particles to be dispersed in the state of primary particles in the material or a cured product thereof.

Such shell polymers are preferably grafted onto the core layer and / or intermediate layer. In addition, hereinafter, when the term "grafted to the core layer" is used, when the intermediate layer is formed in the core layer, the aspect of grafting to the intermediate layer is also included. More precisely, the monomer component used to form the shell layer is grafted onto the core polymer forming the core layer (when the intermediate layer is included, of course, it also means the intermediate layer polymer forming the intermediate layer; the same applies hereinafter). It is preferable that the shell polymer and the rubber polymer are substantially chemically bonded by polymerization (when the rubber polymer has an intermediate layer, of course, it is also preferable that the shell polymer is chemically bonded to the intermediate layer polymer). That is, preferably, the shell polymer is formed by graft-polymerizing the shell-forming monomer in the presence of a core polymer (in the case of having an intermediate layer, it means a core polymer in which an intermediate layer is formed; the same applies hereinafter). By doing so, the core polymer is graft-polymerized and covers a part or the whole of the core polymer. This polymerization operation can be carried out by adding a monomer which is a component of the shell polymer to the latex of the core polymer which is prepared and existing in the state of an aqueous polymer latex and polymerizing it.

As the monomer for forming the shell layer, for example, an aromatic vinyl monomer, a vinyl cyan monomer, and a (meth) acrylate monomer are preferable from the viewpoint of compatibility and dispersibility of the component (B) in the curable resin composition. Meta) acrylate monomers are more preferred. These shell layer forming monomers may be used alone or in combination as appropriate.

The total amount of the aromatic vinyl monomer, vinyl cyan monomer, and (meth) acrylate monomer is preferably 10 to 99.5% by mass, preferably 50 to 99% by mass, in 100% by mass of the shell layer forming monomer. Is more preferable, 65 to 98% by mass is further preferable, 67 to 80% by mass is particularly preferable, and 67 to 85% by mass is most preferable.

From the viewpoint of chemically bonding with the component (A) in order to maintain a good dispersed state without agglomeration of the component (B) in the cured product or polymer, the monomer for forming the shell layer includes an epoxy group, an oxetane group, and a hydroxyl group. , A reactive group-containing monomer containing at least one selected from the group consisting of an amino group, an imide group, a carboxylic acid group, a carboxylic acid anhydride group, a cyclic ester, a cyclic amide, a benzoxazine group, and a cyanate ester group. It is preferably contained, and a monomer having an epoxy group is preferable.

The monomer having an epoxy group is preferably contained in an amount of 0.5 to 90% by mass, more preferably 1 to 50% by mass, still more preferably 2 to 35% by mass, in 100% by mass of the shell-forming monomer. 3 to 20% by mass is particularly preferable. If the monomer having an epoxy group is less than 0.5% by mass in the shell-forming monomer, the impact resistance improving effect of the cured product may be lowered, and the shock peeling adhesiveness of the curable resin composition may also be lowered. There is. If the monomer having an epoxy group is larger than 90% by mass in the shell-forming monomer, the impact resistance improving effect may be lowered, and the storage stability and impact peeling adhesiveness of the curable resin composition may be deteriorated. It may get worse.

The monomer having an epoxy group is preferably used for forming the shell layer, and more preferably used only for the shell layer.

Further, when a polyfunctional monomer having two or more radically polymerizable double bonds is used as the monomer for forming the shell layer, the swelling of the polymer fine particles in the curable resin composition is prevented, and the curable resin composition is also used. It is preferable because it has a low viscosity and tends to be easy to handle. On the other hand, from the viewpoint of the effect of improving the toughness of the obtained cured product and the effect of improving the impact resistance peeling adhesiveness, it is not necessary to use a polyfunctional monomer having two or more radically polymerizable double bonds as the monomer for forming the shell layer. preferable.

The polyfunctional monomer may be contained, for example, 0 to 20% by mass, preferably 1 to 20% by mass, and more preferably 5 to 15% by mass in 100% by mass of the shell-forming monomer. It is mass%.

Specific examples of the aromatic vinyl monomer include vinylbenzenes such as styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene.

Specific examples of the vinyl cyanomer monomer include acrylonitrile and methacrylonitrile.

Specific examples of the (meth) acrylate monomer include (meth) acrylic acid alkyl esters such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) acrylate; hydroxyethyl (meth) acrylate and hydroxybutyl (meth) acrylate. ) Examples thereof include (meth) acrylic acid hydroxyalkyl esters such as acrylate.

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

Specific examples of the polyfunctional monomer having two or more radically polymerizable double bonds include the same monomers as the above-mentioned polyfunctional monomer, but allyl methacrylate and triallyl isocyanurate are preferable.

In the present invention, for example, aromatic vinyl monomer (particularly styrene) 0 to 50% by mass (preferably 1 to 50% by mass, more preferably 2 to 48% by mass), vinyl cyan monomer (particularly acrylonitrile) 0 to 50% by mass. (Preferably 0 to 30% by mass, more preferably 10 to 25% by mass), (meth) acrylate monomer (particularly methyl methacrylate) 0 to 100% by mass (preferably 0 to 90% by mass, more preferably 20 to 85% by mass). %) And a monomer having an epoxy group (particularly glycidyl methacrylate) 0.5 to 50% by mass (preferably 1 to 30% by mass, more preferably 2 to 20% by mass) for forming a shell layer (total 100% by mass). %) It is preferable to use a shell layer which is a polymer. As a result, the desired toughness improving effect and mechanical properties can be realized in a well-balanced manner. In particular, it is preferable to include glycidyl methacrylate as a constituent component because it is considered that the interfacial adhesion with the component (A) is improved.

These monomer components may be used alone or in combination of two or more.

The shell layer may be formed by containing other monomer components in addition to the above-mentioned monomer components.

The graft ratio of the shell layer is preferably 70% or more (more preferably 80% or more, further 90% or more). If the graft ratio is less than 70%, the viscosity of the liquid resin composition may increase. In this specification, the method of calculating the graft ratio is as follows.

First, the aqueous latex containing the polymer fine particles is coagulated and dehydrated, and finally dried to obtain a powder of the polymer fine particles. Next, 2 g of the polymer fine particle powder is immersed in 100 g of methyl ethyl ketone (MEK) at 23 ° C. for 24 hours, and then the MEK-soluble component is separated from the MEK-soluble component, and the methanol-insoluble component is further separated from the MEK-soluble component. Then, the graft ratio is calculated by obtaining the ratio of the MEK insoluble matter to the total amount of the MEK insoluble matter and the methanol insoluble matter.

≪Manufacturing method of polymer fine particles≫
(Manufacturing method of core layer)
The polymer forming the core layer constituting the polymer fine particles used in the present invention contains at least one monomer (first monomer) selected from a diene-based monomer (conjugated diene-based monomer) and a (meth) acrylate-based monomer. If so, the core layer can be formed, for example, by emulsion polymerization, suspension polymerization, microsuspension polymerization, or the like, and for example, the method described in WO2005 / 028546 pamphlet can be used.

When the polymer forming the core layer is composed of a polysiloxane-based polymer, the formation of the core layer can be produced by, for example, emulsion polymerization, suspension polymerization, microsuspension polymerization, or the like. The method described in WO2006 / 070664 pamphlet can be used.

(Method of forming shell layer and intermediate layer)
The intermediate layer can be formed by polymerizing a monomer for forming an intermediate layer by a known radical polymerization. When the rubber elastic body constituting the core layer is obtained as an emulsion, it is preferable to polymerize the monomer having two or more radically polymerizable double bonds by an emulsion polymerization method.

The shell layer can be formed by polymerizing a monomer for forming a shell layer by a known radical polymerization. When a core layer or a polymer particle precursor composed by coating the core layer with an intermediate layer is obtained as an emulsion, the polymerization of the shell layer forming monomer is preferably carried out by an emulsion polymerization method, for example, WO2005. It can be manufactured according to the method described in the / 028546 pamphlet.

Examples of the emulsifier (dispersant) that can be used in emulsification polymerization include alkyl or aryl sulfonic acid represented by dioctyl sulfosuccinic acid and dodecylbenzene sulfonic acid, alkyl or aryl ether sulfonic acid, and alkyl or aryl represented by dodecyl sulfate. Sulfuric acid, alkyl or aryl ether sulfuric acid, alkyl or aryl substituted phosphoric acid, alkyl or aryl ether substituted phosphoric acid, N-alkyl or aryl sarcosic acid represented by dodecyl sarcosic acid, alkyl represented by oleic acid or stearic acid or Various acids such as arylcarboxylic acids, alkyl or arylether carboxylic acids, anionic emulsifiers (dispersants) such as alkali metal or ammonium salts of these acids; nonionic emulsifiers (dispersants) such as alkyl or aryl-substituted polyethylene glycols. ); Dispersants such as polyvinyl alcohol, alkyl-substituted cellulose, polyvinylpyrrolidone, and polyacrylic acid derivatives can be mentioned. These emulsifiers (dispersants) may be used alone or in combination of two or more.

It is preferable to use a small amount of the emulsifier (dispersant) as long as the dispersion stability of the aqueous latex of the polymer particles is not hindered. The higher the water solubility of the emulsifier (dispersant), the more preferable it is. When the water solubility is high, the emulsifier (dispersant) can be easily removed by washing with water, and adverse effects on the finally obtained cured product can be easily prevented.

When the emulsion polymerization method is adopted, a known initiator, that is, 2,2'-azobisisobutyronitrile, hydrogen peroxide, potassium persulfate, ammonium persulfate and the like can be used as the pyrolytic initiator. ..

In addition, organic peroxides such as t-butylperoxyisopropyl carbonate, paramentanhydroperoxide, cumenehydroperoxide, dicumyl peroxide, t-butylhydroperoxide, di-t-butyl peroxide, and t-hexyl peroxide. Oxides: Peroxides such as inorganic peroxides such as hydrogen peroxide, potassium persulfate, ammonium persulfate, and optionally sodium formaldehyde sulfoxylate, reducing agents such as glucose, and optionally iron sulfate (II). ), And if necessary, a chelating agent such as disodium ethylenediamine tetraacetate, and if necessary, a phosphorus-containing compound such as sodium pyrophosphate can be used in combination with a redox-type initiator.

When the redox-type initiator system is used, the polymerization can be carried out even at a low temperature at which the peroxide is substantially not thermally decomposed, and the polymerization temperature can be set in a wide range, which is preferable. Of these, it is preferable to use organic peroxides such as cumene hydroperoxide, dicumyl peroxide, and t-butyl hydroperoxide as the redox-type initiator. The amount of the initiator used, and when the redox-type initiator is used, the amount of the reducing agent, transition metal salt, chelating agent, etc. used can be used within a known range. Further, when polymerizing a monomer having two or more radically polymerizable double bonds, a known chain transfer agent can be used in a known range. Surfactants can be additionally used, but this is also in the known range.

Conditions such as polymerization temperature, pressure, and deoxidation at the time of polymerization can be applied within a known range. Further, the polymerization of the intermediate layer forming monomer may be carried out in one stage or in two or more stages. For example, in addition to the method of adding the monomer for forming the intermediate layer to the emulsion of the rubber elastic body constituting the elastic core layer at once and the method of continuously adding the monomer, the elastic core layer is added to the reactor in which the monomer for forming the intermediate layer is preliminarily charged. It is possible to adopt a method of performing polymerization after adding an emulsion of the constituent rubber elastic material.

<Surface-treated calcium oxide (C)> 0.1 to 10 parts by mass The curable resin composition of the present invention contains 0.1 parts by mass of surface-treated calcium oxide (C) with respect to 100 parts by mass of the component (A). It is essential to contain 10 parts by mass.

The component (C) removes water by reacting with water in the curable resin composition, and solves various physical property problems caused by the presence of water. For example, it functions as an anti-bubble agent by removing water and suppresses a decrease in adhesive strength.

It is essential that the component (C) is surface-treated with a surface treatment agent. The surface treatment improves the dispersibility of the component (C) in the composition. As a result, as compared with the case where calcium oxide without surface treatment is used, the improvement mechanism is unknown, but the physical properties such as the adhesive strength of the obtained cured product are improved. In particular, the T-shaped peeling adhesiveness and the impact resistant peeling adhesiveness are remarkably improved. The surface treatment agent is not particularly limited, but fatty acids are preferable.

The amount of the component (C) used is 0.1 to 10 parts by mass, preferably 0.2 to 5 parts by mass, and more preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the component (A). , 1 to 2 parts by mass is particularly preferable. If it is less than 0.1 parts by mass, the water removing effect may not be sufficient, and if it is more than 10 parts by mass, the strength of the obtained cured product may be low.

The component (C) may be used alone or in combination of two or more.

In the present invention, calcium oxide other than the component (C), that is, calcium oxide without surface treatment can be contained in a small amount so as not to reduce the effect of the present invention.

The surface-treated calcium oxide is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, further preferably 10 parts by mass or less, and 5 parts by mass or less with respect to 100 parts by mass of the surface-treated calcium oxide (C). Is particularly preferable, and it is most preferable that it does not contain substantially surface-untreated calcium oxide. If the amount of untreated surface-treated calcium oxide is more than 50 parts by mass, the storage stability and adhesiveness of the cured product may decrease.

<Epoxy resin curing agent (D)>
In the present invention, the epoxy resin curing agent (D) can be used if necessary.

When the curable resin composition of the present invention is used as a one-component composition (such as a one-component curable resin composition), the adhesive rapidly reacts when heated to a temperature of 80 ° C. or higher, preferably 140 ° C. or higher. It is preferable to select the component (D) so as to cure. On the contrary, it is preferable to select the component (D) and the component (E) described later so that the curing is very slow even if it cures at room temperature (about 22 ° C.) or at a temperature of at least 50 ° C.

As the component (D), a component that exhibits activity by heating (sometimes referred to as a latent curing agent) can be used. As such a latent epoxy curing agent, an N-containing curing agent such as a specific amine-based curing agent (including an imine-based curing agent) can be used, and for example, a boron trichloride / amine complex or a boron trifluoride / amine can be used. Complex, dicyandiamide, melamine, diallyl melamine, guanamine (eg, acetguanamine and benzoguanamine), aminotriazole (eg, 3-amino-1,2,4-triazole), hydrazide (eg, adipic acid dihydrazide, stearate dihydrazide, isophthal). Acid dihydrazide, semicarbazide), cyanoacetamide, and aromatic polyamines (eg, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, etc.). It is more preferable to use dicyandiamide, isophthalic acid dihydrazide, adipic acid dihydrazide, and 4,4'-diaminodiphenyl sulfone, and dicyandiamide is particularly preferable.

Among the above-mentioned curing agents (D), the latent epoxy curing agent is preferable because the curable resin composition of the present invention can be liquefied.

On the other hand, when the curable resin composition of the present invention is used as a two-component or multi-component composition, amine-based curing agents (including imine-based curing agents) and mercaptan-based curing agents (room temperature curable curing) other than the above are used. (Sometimes referred to as an agent) can be selected as the component (D) that exhibits activity at a relatively low temperature of about room temperature.

Examples of the component (D) that exhibits activity at a relatively low temperature include chain aliphatic polyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diproprenedamine, diethylaminopropylamine, and hexamethylenediamine; N- Aminoethyl piberazine, bis (4-amino-3-methylcyclohexyl) methane, mensendiamine, isophoronediamine, 4,4'-diaminodicyclohexylmethane, 3,9-bis (3-aminopropyl) -2,4 , 8,10-Tetraoxaspiro [5.5] Cyclic aliphatic polyamines such as undecane (spiroacetaldiamine), norbornanamine, tricyclodecanediamine, 1,3-bisaminomethylcyclohexane; fats such as metaxylene diamine Aromatic amines; Polyamines, which are reaction products of epoxy resins and excess polyamines Adducts; Ketimines, which are dehydration reaction products of polyamines and ketones such as methyl ethyl ketone and isobutyl methyl ketone; Two of tall oil fatty acids Polyamineamines produced by the condensation of a metric (dimeric acid) and a polyamine; amidoamines produced by the condensation of a toll oil fatty acid and a polyamine; polymercaptans and the like can be mentioned.

Amine-terminated polyethers containing a polyether backbone and having an average of 1 to 4 (preferably 1.5 to 3) amino and / or imino groups per molecule are also used as component (D). it can. Examples of commercially available amine-terminated polyethers include Huntsman's Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, and Jeffamine T-5000.

In addition, amine-terminated rubbers containing a conjugated diene polymer backbone and having an average of 1 to 4 (more preferably 1.5 to 3) amino and / or imino groups per molecule are also (D). ) Can be used as an ingredient. Here, the main chain of the rubber is preferably a homopolymer or copolymer of polybutadiene, more preferably a polybutadiene / acrylonitrile copolymer, and the acrylonitrile monomer content is 5 to 40% by mass (more preferably 10 to 35% by mass, further preferably 15 to 15 to A polybutadiene / acrylonitrile copolymer of 30% by weight) is particularly preferred. Examples of commercially available amine-terminated rubbers include Hypro 1300X16 ATBN manufactured by CVC.

Among the amine-based curing agents that show activity at a relatively low temperature of about room temperature, polyamide amines, amine-terminated polyethers, and amine-terminated rubbers are more preferable, and polyamide amines, amine-terminated polyethers, and amine-terminated rubbers are used. It is particularly preferable to use them together.

Further, as the component (D), acid anhydrides, phenols and the like can also be used. Acid anhydrides and phenols require higher temperatures than amine-based curing agents, but they have a long pot life, and the cured products have a good balance of physical properties such as electrical properties, chemical properties, and mechanical properties. Is. Examples of acid anhydrides include polysebacic acid polyanhydride, polyazelineic acid polyanhydride, succinic anhydride, citraconic acid anhydride, itaconic acid anhydride, alkenyl-substituted succinic acid anhydride, dodecenyl succinic acid anhydride, maleic anhydride, and so on. Tricarbarylic anhydride, nadonic anhydride, methylnadonic anhydride, linoleic acid adduct with maleic anhydride, alkylated terminal alkylene tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, hexahydro Phtalic anhydride, pyromellitic dianhydride, trimellitic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, dichloromaleic anhydride, chloronadic anhydride, and chlorendic acid. Anhydrides, maleic anhydride-grafted polybutadiene and the like can be mentioned. Examples of phenols include phenol novolac, bisphenol A novolak, and cresol novolak.

The component (D) may be used alone or in combination of two or more.

The component (D) is used in an amount sufficient to cure the composition. Typically, sufficient curing agent is supplied to consume at least 80% of the epoxide groups present in the composition. Large excesses above the amount required to consume the epoxide group are usually not needed. The amount of the component (D) used is preferably 1 to 80 parts by mass, more preferably 2 to 40 parts by mass, further preferably 3 to 30 parts by mass, and 5 to 20 parts by mass with respect to 100 parts by mass of the component (A). Part is particularly preferable. If it is less than 1 part by mass, the curability of the curable resin composition of the present invention may deteriorate. If it is more than 80 parts by mass, the storage stability of the curable resin composition of the present invention is poor, and it may be difficult to handle.

<Curing accelerator (E)>
In the present invention, the curing accelerator (E) can be used if necessary.

The component (E) is a catalyst for accelerating the reaction of the epoxy group with the epoxide-reactive group on other components of the curing agent or adhesive).

Examples of the component (E) include p-chlorophenyl-N, N-dimethylurea (trade name: Mouron), 3-phenyl-1,1-dimethylurea (trade name: Phenuron), and 3,4-dichlorophenyl-N. , N-Dimethylurea (trade name: Diuron), N- (3-chloro-4-methylphenyl) -N', N'-dimethylurea (trade name: Chlortroluron), 1,1-dimethylphenylurea (trade name) Ureas such as Dyhard); benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, 2- (dimethylaminomethyl) phenol, 2,4 incorporated into a poly (p-vinylphenol) matrix. , 6-Tris (dimethylaminomethyl) phenol, triethylenediamine, N, N-dimethylpiperidine and other tertiary amines; C1-C12 alkylene imidazole, N-aryl imidazole, 2-methyl imidazole, 2-ethyl-2-methyl Imidazoles such as imidazole, N-butylimidazole, 1-cyanoethyl-2-undecyl imidazolium trimerite, addition product of epoxy resin and imidazole; 6-caprolactam and the like. The catalyst may be encapsulated or potentially active only when the temperature is raised.

The tertiary amines and imidazoles can be used in combination with the amine-based curing agent of the component (D) to improve the curing rate, cured physical properties, heat resistance and the like.

The component (E) may be used alone or in combination of two or more.

The amount of the component (E) used is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 5 parts by mass, and further preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the component (A). Preferably, 0.8 to 2 parts by mass is particularly preferable. If it is less than 0.1 parts by mass, the curability of the curable resin composition of the present invention may deteriorate. If it is more than 10 parts by mass, the storage stability of the curable resin composition of the present invention is poor, and it may be difficult to handle.

<Strengthening agents other than component (B)>
In the present invention, for the purpose of further improving the performance such as toughness, impact resistance, shear adhesiveness, and peeling adhesiveness, as a reinforcing agent other than the component (B), a rubber-modified epoxy resin, a urethane-modified epoxy resin, or a urethane-modified epoxy resin, or , Blocked urethane can be used as needed.

The fortifiers other than the component (B) may be used alone or in combination of two or more.

<Rubber-modified epoxy resin>
The rubber-modified epoxy resin is a reaction product obtained by reacting rubber with an epoxy group-containing compound and having 1.1 or more, preferably two or more epoxy groups on average per molecule, and is used as rubber. Acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), hydrogenated nitrile rubber (HNBR), ethylene propylene rubber (EPDM), acrylic rubber (ACM), butyl rubber (IIR), butadiene rubber, polypropylene oxide and polyethylene oxide. And rubber-based polymers such as polyoxyalkylene such as polytetramethylene oxide. The rubber-based polymer preferably has a reactive group such as an amino group, a hydroxy group, or a carboxyl group at the end. The rubber-modified epoxy resin used in the present invention is a product obtained by reacting these rubber-based polymers with an epoxy resin in an appropriate compounding ratio by a known method. Among these, acrylonitrile-butadiene rubber-modified epoxy resin and polyoxyalkylene-modified epoxy resin are preferable from the viewpoint of adhesiveness and impact-resistant peeling adhesiveness of the obtained curable resin composition, and acrylonitrile-butadiene rubber-modified epoxy resin is preferable. More preferred. The acrylonitrile-butadiene rubber-modified epoxy resin is obtained, for example, by reacting a carboxyl group-terminated NBR (CTBN) with a bisphenol A type epoxy resin.

The content of the acrylonitrile monomer component in the acrylonitrile-butadiene rubber is preferably 5 to 40% by mass, preferably 10 to 35% by mass, from the viewpoint of the adhesiveness and impact-resistant peeling adhesiveness of the obtained curable resin composition. Is more preferable, and 15 to 30% by mass is further preferable. From the viewpoint of workability of the obtained curable resin composition, 20 to 30% by mass is particularly preferable.

Further, for example, an addition reaction product of an amino group-terminated polyoxyalkylene and an epoxy resin (hereinafter, also referred to as “adduct”) is also included in the rubber-modified epoxy resin. The adduct can be easily produced by a known method, for example, as described in US Pat. No. 5,854,532, US Pat. No. 6015865, and the like. Examples of the epoxy resin used in producing the adduct include specific examples of the component (A) exemplified in the present invention, but bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferable, and bisphenol A is preferable. Type epoxy resin is more preferable. Commercially available amino group-terminated polyoxyalkylenes used in the production of adducts include, for example, Jeffamine D-230, Jeffamine D-400, Jeffamine D-2000, Jeffamine D-4000, manufactured by Huntsman Corporation. Jeffamine T-5000, etc. can be mentioned.

The average number of epoxide-reactive end groups per molecule in the rubber is preferably 1.5 to 2.5, more preferably 1.8 to 2.2. The number average molecular weight of the rubber is preferably 1000 to 10000, more preferably 2000 to 8000, and particularly preferably 3000 to 6000 in terms of polystyrene-equivalent molecular weight measured by GPC.

The production method of the rubber-modified epoxy resin is not particularly limited, and for example, it can be produced by reacting rubber with an epoxy group-containing compound in a large amount of epoxy group-containing compound. Specifically, it is preferably produced by reacting 2 equivalents or more of an epoxy group-containing compound with 1 equivalent of an epoxy-reactive end group in rubber. It is more preferable that the obtained product reacts with an epoxy group-containing compound in an amount sufficient to form a mixture of the adduct of the rubber and the epoxy group-containing compound and the free epoxy group-containing compound. For example, a rubber-modified epoxy resin is produced by heating to a temperature of 100 to 250 ° C. in the presence of a catalyst such as phenyldimethylurea or triphenylphosphine. The epoxy group-containing compound used in producing the rubber-modified epoxy resin is not particularly limited, but a bisphenol A type epoxy resin or a bisphenol F type epoxy resin is preferable, and a bisphenol A type epoxy resin is more preferable. In the present invention, when an excessive amount of the epoxy group-containing compound is used in the production of the rubber-modified epoxy resin, the unreacted epoxy group-containing compound remaining after the reaction is used in the rubber-modified epoxy resin of the present invention. , Not included.

In the rubber-modified epoxy resin, the epoxy resin can be modified by pre-reacting with the bisphenol component. The bisphenol component used for the modification is preferably 3 to 35 parts by mass, more preferably 5 to 25 parts by mass, based on 100 parts by mass of the rubber component in the rubber-modified epoxy resin. The cured product obtained by curing the curable resin composition containing the modified rubber-modified epoxy resin is excellent in adhesive durability after high temperature exposure and also excellent in impact resistance at low temperature.

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

The number average molecular weight of the rubber-modified epoxy resin is preferably 1500 to 40,000, more preferably 3000 to 30000, and particularly preferably 4000 to 20000 in terms of polystyrene-equivalent molecular weight measured by GPC. The molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

The amount of the rubber-modified epoxy resin used is preferably 1 to 50 parts by mass, more preferably 2 to 40 parts by mass, further preferably 5 to 30 parts by mass, and 10 to 20 parts by mass with respect to 100 parts by mass of the component (A). Part is particularly preferable. If it is less than 1 part by mass, the obtained cured product may be brittle and the impact resistance peeling adhesiveness may be low, and if it is more than 50 parts by mass, the heat resistance and elastic modulus (rigidity) of the obtained cured product may be low.

The rubber-modified epoxy resin can be used alone or in combination of two or more.

<Urethane modified epoxy resin>
The urethane-modified epoxy resin is obtained by reacting a compound containing a group having a reactivity with an isocyanate group and an epoxy group with a urethane prepolymer containing an isocyanate group, and an epoxy group is averaged per molecule. It is a reaction product having 1.1 or more, preferably 2 or more. For example, a urethane-modified epoxy resin can be obtained by reacting a hydroxy group-containing epoxy compound with a urethane prepolymer.

The number average molecular weight of the urethane-modified epoxy resin is preferably 1500 to 40,000, more preferably 3000 to 30000, and particularly preferably 4000 to 20000 in terms of polystyrene-equivalent molecular weight measured by GPC. The molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

The amount of the urethane-modified epoxy resin used is preferably 1 to 50 parts by mass, more preferably 2 to 40 parts by mass, further preferably 5 to 30 parts by mass, and 10 to 20 parts by mass with respect to 100 parts by mass of the component (A). Part is particularly preferable. If it is less than 1 part by mass, the obtained cured product may be brittle and the impact resistance peeling adhesiveness may be low, and if it is more than 50 parts by mass, the heat resistance and elastic modulus (rigidity) of the obtained cured product may be low.

The urethane-modified epoxy resin can be used alone or in combination of two or more.

<Blocked urethane>
Blocked urethane is an elastomer type, and contains various blocks containing a urethane group and / or a urea group, and all or part of the terminal isocyanate group of the compound having an isocyanate group at the terminal has an active hydrogen group. It is a compound capped with an agent. In particular, a compound in which all of the terminal isocyanate groups are capped with a blocking agent is preferable. In such a compound, for example, an organic polymer having an active hydrogen-containing group at the terminal is reacted with an excess polyisocyanate compound to have a urethane group and / or a urea group in the main chain and an isocyanate group at the terminal. It can be obtained by capping all or part of the isocyanate groups with a blocking agent having an active hydrogen group after or at the same time as the polymer having a urethane prepolymer.

The blocked urethane is, for example, the following general formula (1):
A- (NR ^2- C (= O) -X) _a (1)
(In the formula, a R ² is an independently hydrocarbon group having 1 to 20 carbon atoms. A represents the average number of capped isocyanate groups per molecule, and 1.1 or more. Is preferable, 1.5 to 8 is more preferable, 1.7 to 6 is even more preferable, and 2 to 4 is particularly preferable. X is a residue obtained by removing an active hydrogen atom from the blocking agent. Is a residue obtained by removing the terminal isocyanate group from the isocyanate-terminated prepolymer.).

The number average molecular weight of the blocked urethane is preferably 2000 to 40,000, more preferably 3000 to 30000, and particularly preferably 4000 to 20000 in terms of polystyrene-equivalent molecular weight measured by GPC. The molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) is preferably 1 to 4, more preferably 1.2 to 3, and particularly preferably 1.5 to 2.5.

(Organic polymer having an active hydrogen-containing group at the C-1 terminal)
The main chain skeleton constituting the organic polymer having an active hydrogen-containing group at the terminal includes a polyether polymer, a polyacrylic polymer, a polyester polymer, a polydiene polymer, and a saturated hydrocarbon polymer (polyolefin). ), Polythioether-based polymers and the like.

(Active hydrogen group)
Examples of the active hydrogen-containing group constituting the organic polymer having an active hydrogen-containing group at the terminal include a hydroxyl group, an amino group, an imino group, and a thiol group. Among these, a hydroxyl group, an amino group, and an imino group are preferable from the viewpoint of availability, and a hydroxyl group is more preferable from the viewpoint of ease of handling (viscosity) of the obtained blocked urethane.

Examples of the organic polymer having an active hydrogen-containing group at the terminal include a polyether polymer having a hydroxyl group at the terminal (polyether polyol) and a polyether polymer having an amino group and / or an imino group at the terminal (polyether amine). ), Polyacrylic polyol, polyester polyol, diene polymer having a hydroxyl group at the terminal (polydiene polyol), saturated hydrocarbon polymer having a hydroxyl group at the terminal (polyolefin polyol), polythiol compound, polyamine compound and the like. Among these, the polyether polyol, the polyether amine, and the polyacrylic polyol have excellent compatibility with the component (A), the glass transition temperature of the organic polymer is relatively low, and the obtained cured product is at a low temperature. It is preferable because it has excellent impact resistance. In particular, the polyether polyol and the polyether amine are more preferable because the viscosity of the obtained organic polymer is low and the workability is good, and the polyether polyol is particularly preferable.

The organic polymer having an active hydrogen-containing group at the terminal, which is used when preparing the urethane prepolymer which is a precursor of blocked urethane, may be used alone or in combination of two or more.

The number average molecular weight of the organic polymer having an active hydrogen-containing group at the terminal is preferably 800 to 7000, more preferably 1500 to 5000, and particularly preferably 2000 to 4000, in terms of polystyrene-equivalent molecular weight measured by GPC.

(Polyether-based polymer)
The polyether polymer is essentially a general formula (2):
-R ¹ -O- (2)
(In the formula, R ¹ is a linear or branched alkylene group having 1 to 14 carbon atoms.) A polymer having a repeating unit represented by the formula, R ¹ in the general formula (2) is a carbon atom. Linear or branched alkylene groups of numbers 1 to 14, more preferably 2 to 4, are preferred. As a specific example of the repeating unit represented by the general formula (2),
_{-CH 2 O -, - CH 2} CH 2 O -, - CH 2 CH (CH 3) O -, - CH 2 CH (C 2 H 5) O -, - CH 2 C (CH 3) 2 O-, −CH ₂ CH ₂ CH ₂ CH ₂ O−
And so on. The main chain skeleton of the polyether polymer may consist of only one type of repeating unit or may consist of two or more types of repeating units. In particular, a polymer containing polypropylene glycol as a main component having a repeating unit of propylene oxide of 50% by mass or more is preferable from the viewpoint of T-shaped peeling adhesive strength. Further, polytetramethylene glycol (PTMG) obtained by ring-opening polymerization of tetrahydrofuran is preferable from the viewpoint of dynamic splitting resistance.

When used in combination with the component (B), the ratio of the component (B) to the blocked urethane is preferably 0.1 to 10, more preferably 0.2 to 5, and 0.3. It is particularly preferable that it is ~ 1.

(Polyether polyol)
The polyether polyol is a polyether-based polymer having a hydroxyl group at the terminal, and the polyether amine is a polyether-based polymer having an amino group or an imino group at the terminal.

(Polyacrylic polyol)
Examples of the polyacrylic polyol include a polyol having a (meth) acrylic acid alkyl ester (co) polymer as a skeleton and having a hydroxyl group in the molecule. In particular, a polyacrylic polyol obtained by copolymerizing a hydroxyl group-containing (meth) acrylic acid alkyl ester monomer such as 2-hydroxyethyl methacrylate is preferable.

Examples of the polyester polyol include polybasic acids such as maleic acid, fumaric acid, adipic acid, and phthalic acid and their acid anhydrides, ethylene glycol, propylene glycol, 1,4-butanediol, and 1,6-hexanediol. Examples thereof include polymers obtained by polycondensing polyhydric alcohols such as diethylene glycol, dipropylene glycol, and neopentyl glycol in the presence of an esterification catalyst in a temperature range of 150 to 270 ° C. Further, ring-opening polymers such as ε-caprolactone and valerolactone and active hydrogen compounds having two or more active hydrogens such as polycarbonate diol and castor oil can also be mentioned.

(Polydiene polyol)
Examples of the polydiene polyol include polybutadiene polyol, polyisoprene polyol, polychloroprene polyol, and the like, and polybutadiene polyol is particularly preferable.

(Polyolefin polyol)
Examples of the polyolefin polyol include polyisobutylene polyol and hydrogenated polybutadiene polyol.

(C-2 polyisocyanate)
Specific examples of the polyisocyanate compound include aromatic polyisocyanates such as toluene (trilen) diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; and fats such as isophorone diisocyanate, hexamethylene diisocyanate, hydride toluene diisocyanate, and hydride diphenylmethane diisocyanate. Examples thereof include group polyisocyanates. Among these, an aliphatic polyisocyanate is preferable from the viewpoint of heat resistance, and isophorone diisocyanate and hexamethylene diisocyanate are more preferable from the viewpoint of availability.

(C-3 blocking agent)
The blocking agent is, for example, a primary amine blocking agent, a secondary amine blocking agent, an oxime blocking agent, a lactam blocking agent, an active methylene blocking agent, an alcohol blocking agent, a mercaptan blocking agent, an amide. Examples thereof include system-based blocking agents, imide-based blocking agents, heterocyclic aromatic compound-based blocking agents, hydroxy-functional (meth) acrylate-based blocking agents, and phenol-based blocking agents. Among these, oxime-based blocking agents, lactam-based blocking agents, hydroxy-functional (meth) acrylate-based blocking agents, and phenol-based blocking agents are preferable, and hydroxy-functional (meth) acrylate-based blocking agents and phenol-based blocking agents are more preferable. , Phenolic blocking agents are more preferred.

(Primary amine-based blocking agent)
Examples of the primary amine-based blocking agent include butylamine, isopropylamine, dodecylamine, cyclohexylamine, aniline, and benzylamine. Examples of the secondary amine-based blocking agent include dibutylamine, diisopropylamine, dicyclohexylamine, diphenylamine, dibenzylamine, morpholine, piperidine, and the like. Examples of the oxime-based blocking agent include formaldoxime, acetaldoxime, acetaldoxime, methylethylketooxime, diacetylmonooxime, cyclohexaneoxime and the like. Examples of the lactam-based blocking agent include ε-caprolactam, δ-valerolactam, γ-butyrolactam, β-butyrolactam and the like. Examples of the active methylene-based blocking agent include ethyl acetoacetate and acetylacetone. Examples of the alcohol-based blocking agent include methanol, ethanol, propanol, isopropanol, butanol, amyl alcohol, cyclohexanol, 1-methoxy-2-propanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and benzyl alcohol. , Methyl glycolate, butyl glycolate, diacetone alcohol, methyl lactate, ethyl lactate and the like. Examples of the mercaptan-based blocking agent include butyl mercaptan, hexyl mercaptan, decyl mercaptan, t-butyl mercaptan, thiophenol, methyl thiophenol, ethyl thiophenol and the like. Examples of the amide-based blocking agent include acetic acid amide and benzamide. Examples of the imide-based blocking agent include succinimide and maleate imide. Examples of the heterocyclic aromatic compound-based blocking agent include imidazoles such as imidazole and 2-ethylimidazole, pyrroles such as pyrrole, 2-methylpyrrole and 3-methylpyrrole, pyridine, 2-methylpyridine and 4-methyl. Examples thereof include pyridines such as pyridine and diazabicycloalkenes such as diazabicycloundecene and diazabicyclononen.

(Hydroxyfunctional (meth) acrylate-based blocking agent)
The hydroxyfunctional (meth) acrylate-based blocking agent is a (meth) acrylate having one or more hydroxyl groups. Specific examples of the hydroxyfunctional (meth) acrylate-based blocking agent include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 2-hydroxybutyl (meth). Examples thereof include acrylate.

(Phenol blocking agent)
The phenolic blocking agent contains at least one phenolic hydroxyl group, that is, a hydroxyl group directly bonded to the carbon atom of the aromatic ring. The phenolic compound may have two or more phenolic hydroxyl groups, but preferably contains only one phenolic hydroxyl group. The phenolic compound may contain other substituents, but these substituents preferably do not react with the isocyanate group under the conditions of the capping reaction, and an alkenyl group or an allyl group is preferable. Other substituents include alkyl groups such as linear, branched or cycloalkyl; aromatic groups (eg, phenyl, alkyl substituted phenyl, alkenyl substituted phenyl, etc.); aryl substituted alkyl groups; phenol substituted alkyl groups. Can be mentioned. Specific examples of phenol-based blocking agents include phenol, cresol, xylenol, chlorophenol, ethylphenol, allylphenol (particularly o-allylphenol), resorcinol, catechol, hydroquinone, bisphenol, bisphenol A, and bisphenol AP (1,1-). Bis (4-hydroxylphenyl) -1-phenylethane), bisphenol F, bisphenol K, bisphenol M, tetramethylbiphenol and 2,2'-diallyl-bisphenol A, and the like can be mentioned.

The blocking agent is preferably attached to the end of the polymer chain of the urethane prepolymer in such a manner that the end to which it is attached no longer has a reactive group.

The blocking agent may be used alone or in combination of two or more.

The blocked urethane may contain a residue of a cross-linking agent, a residue of a chain extender, or both.

(Crosslinking agent)
The cross-linking agent preferably has a molecular weight of 750 or less, more preferably 50 to 500, and is a polyol or polyamine compound having at least 3 hydroxyl groups, amino groups and / or imino groups per molecule. The cross-linking agent is useful for imparting branching to the blocked urethane and increasing the functional value of the blocked urethane (ie, the number of capped isocyanate groups per molecule).

(Chain extender)
The chain extender preferably has a molecular weight of 750 or less, more preferably 50 to 500, and is a polyol or polyamine compound having two hydroxyl groups, amino groups and / or imino groups per molecule. Chain extenders are useful for increasing the molecular weight of blocked urethane without increasing the functional value.

Specific examples of the cross-linking agent and chain extender include trimethylolpropane, glycerin, trimethylolethane, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, sucrose, sorbitol, pentaerythritol, ethylenediamine, triethanolamine, and monoethanol. Examples include amine, diethanolamine, piperazine and aminoethylpiperazine. In addition, resorcinol, catechol, hydroquinone, bisphenol, bisphenol A, bisphenol AP (1,1-bis (4-hydroxyphenyl) -1-phenylethane), bisphenol F, bisphenol K, bisphenol M, tetramethylbiphenol, 2,2 Also included are compounds having two or more phenolic hydroxyl groups, such as'-diallyl-bisphenol A.

(Amount of blocked urethane)
The amount of blocked urethane is preferably 1 to 50 parts by mass, more preferably 10 to 40 parts by mass, and particularly preferably 10 to 35 parts by mass with respect to 100 parts by mass of the epoxy resin (A). If it is less than 1 part by mass, the modifying effects such as toughness, impact resistance, and adhesiveness may not be sufficient, and if it is more than 50 parts by mass, the elastic modulus of the obtained cured product may be low.

<Inorganic filler>
In the curable resin composition of the present invention, silicic acid and / or silicate can be added as an inorganic filler.

Specific examples include dry silica, wet silica, aluminum silicate, magnesium silicate, calcium silicate, wollastonite, talc, and the like.

The dry silica is also called fumed silica, and is produced by chemically treating the surface-untreated hydrophilic fumed silica and the silanol group portion of the hydrophilic fumed silica with silane or siloxane. However, hydrophobic fumed silica is preferable from the viewpoint of dispersibility in the component (A).

Other inorganic fillers include reinforcing fillers such as dolomite and carbon black; calcium carbonate, heavy calcium carbonate, magnesium carbonate, titanium oxide, ferric oxide, fine aluminum powder, zinc oxide, active zinc oxide, etc. Can be mentioned. In particular, heavy calcium carbonate is preferable from the viewpoint of dynamic split resistance.

The inorganic filler is preferably surface-treated with a surface treatment agent. The surface treatment improves the dispersibility of the inorganic filler in the composition, and as a result, the various physical properties of the obtained cured product are improved. In particular, surface-treated heavy calcium carbonate is preferable from the viewpoint of dynamic splitting resistance.

The amount of the inorganic filler used is preferably 1 to 100 parts by mass, more preferably 2 to 70 parts by mass, further preferably 5 to 40 parts by mass, and 7 to 20 parts by mass with respect to 100 parts by mass of the component (A). Is particularly preferable.

The inorganic filler may be used alone or in combination of two or more.

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

Examples of the radical curable resin include unsaturated polyester resins, polyester (meth) acrylates, epoxy (meth) acrylates, urethane (meth) acrylates, polyether (meth) acrylates, and acrylicized (meth) acrylates. These may be used alone or in combination. Specific examples of the radical curable resin include the compounds described in WO2014-115778. Specific examples of the low molecular weight compound and the radical polymerization initiator include the compounds described in WO2014-115778.

As described in WO2010-019539, if the radical polymerization initiator is activated at a temperature different from the curing temperature of the epoxy resin, the curable resin composition is partially cured by the selective polymerization of the radical curable resin. It will be possible. By this partial curing, the viscosity of the composition can be increased after application, and the wash-off resistance can be improved. In the water-washing shower process on a production line such as a vehicle, the uncured adhesive composition is partially dissolved, scattered, or deformed by the shower water pressure during the water-washing shower process. The corrosion resistance of the steel sheet in the coated portion may be adversely affected or the rigidity of the steel sheet may be reduced, and the "difficulty of being washed off" means resistance to this problem. Further, this partial curing can provide a function of temporarily fixing (temporarily adhering) the substrates to each other until the curing of the composition is completed. In this case, the free radical initiator is preferably activated by heating to 80 ° C. to 130 ° C., more preferably 100 ° C. to 120 ° C.

<Monoepoxide>
In the present invention, monoepoxide can be used if necessary. The monoepoxide can function as a reactive diluent. Specific examples of monoepoxides include aliphatic glycidyl ethers such as butyl glycidyl ether, aromatic glycidyl ethers such as phenyl glycidyl ether and cresyl glycidyl ether, and 8 to 10 carbon atoms such as 2-ethylhexyl glycidyl ether. An ether composed of an alkyl group and a glycidyl group, for example, an ether composed of a phenyl group having 6 to 12 carbon atoms and a glycidyl group which can be substituted with an alkyl group having 2 to 8 carbon atoms such as p-tert butylphenyl glycidyl ether, for example, dodecyl. Ether consisting of an alkyl group having 12 to 14 carbon atoms such as glycidyl ether and a glycidyl group; for example, an aliphatic glycidyl ester such as glycidyl (meth) acrylate and glycidyl maleate; Examples thereof include glycidyl esters of aliphatic carboxylic acids having 8 to 12 carbon atoms such as esters; pt-butyl benzoic acid glycidyl esters and the like.

When monoepoxide is used, the amount used is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and 1 to 5 parts by mass with respect to 100 parts by mass of the component (A). Especially preferable. If it is less than 0.1 parts by mass, the effect of reducing the viscosity may not be sufficient, and if it is more than 20 parts by mass, physical properties such as adhesiveness may be deteriorated.

<Photopolymerization initiator>
Further, when the curable resin composition of the present invention is photocured, a photopolymerization initiator may be added. Examples of such photopolymerization initiators include onium salts such as aromatic sulfonium salts and aromatic iodonium salts with anions such as hexafluoroantimonate, hexafluorophosphate and tetraphenylborate, and light such as aromatic diazonium salts and metallocene salts. Examples thereof include a cationic polymerization initiator (photoacid generator). These photopolymerization initiators may be used alone or in combination of two or more.

<Other ingredients>
In the present invention, other compounding ingredients can be used, if necessary. Other compounding ingredients include azotype chemical foaming agents, expansion agents such as thermoplastic microballoons, fiber pulps such as aramid-based pulps, colorants such as pigments and dyes, extender pigments, ultraviolet absorbers, antioxidants, etc. Stabilizers (antigels), plasticizers, leveling agents, defoaming agents, silane coupling agents, antistatic agents, flame retardants, lubricants, thickeners, low shrinkage agents, organic fillers, thermoplastic resins, Examples thereof include a desiccant and a dispersant.

<Manufacturing method of curable resin composition>
The curable resin composition of the present invention is a composition containing polymer fine particles (B) in a curable resin composition containing the component (A) as a main component, and the polymer fine particles (B) are preferably 1. It is a composition dispersed in the state of secondary particles.

Various methods can be used as a method for obtaining such a composition in which the polymer fine particles (B) are dispersed in the state of primary particles. For example, the polymer fine particles obtained in the aqueous latex state are used as the component (A). Examples thereof include a method of removing unnecessary components such as water after contact, a method of extracting polymer fine particles into an organic solvent, mixing the polymer fine particles with the component (A), and then removing the organic solvent. WO2005 / 028546 It is preferable to use the method described in the brochure. The specific production method is as follows, in order, an aqueous latex containing the polymer fine particles (B) (specifically, a reaction mixture after producing the polymer fine particles by emulsion polymerization) has a solubility in water at 20 ° C. of 5% by mass. The first step of aggregating the polymer particles by mixing with an organic solvent of 40% by mass or more and then mixing with excess water, and separating and recovering the agglomerated polymer fine particles (B) from the liquid phase, and then again. It includes a second step of mixing with an organic solvent to obtain an organic solvent solution of the polymer fine particles (B), and a third step of further mixing the organic solvent solution with the component (A) and then distilling off the organic solvent. It is preferably prepared in.

It is preferable that the component (A) is liquid at 23 ° C. because the third step is facilitated. "Liquid at 23 ° C." means that the softening point is 23 ° C. or lower, and exhibits fluidity at 23 ° C.

In the composition obtained through the above steps, in which the polymer fine particles (B) are dispersed in the component (A) in the state of primary particles, the component (A), the component (C), the component (D), and (E) are further added. By further mixing the components and each component of the other compounding components as necessary, the curable resin composition of the present invention in which the polymer fine particles (B) are dispersed in the state of primary particles can be obtained.

On the other hand, the powdery polymer fine particles (B) obtained by solidifying by a method such as salting out and then drying use a disperser having a high mechanical shearing force such as a three-paint roll, a roll mill, or a kneader. It is possible to redisperse in the component (A). At this time, the component (A) and the component (B) can efficiently disperse the component (B) by applying a mechanical shearing force at a high temperature. The temperature at the time of dispersion is preferably 50 to 200 ° C., more preferably 70 to 170 ° C., further preferably 80 to 150 ° C., and particularly preferably 90 to 120 ° C. If the temperature is lower than 50 ° C., the component (B) may not be sufficiently dispersed, and if the temperature is higher than 200 ° C., the components (A) and (B) may be thermally deteriorated.

The curable resin composition of the present invention can be used as a one-component curable resin composition in which all the compounding components are premixed, stored in a sealed container, and cured by heating or light irradiation after application. Further, the liquid A containing the component (A) as the main component and further containing the component (B) and, if necessary, the component (C), and the component (D) and the component (E) are further contained, and if necessary. Prepare as a two-component or multi-component curable resin composition consisting of a separately prepared solution B containing the component (B) and / or the component (C), and use the solution A and the solution B. It can also be mixed and used before. The curable composition of the present invention is particularly useful when used as a one-component curable resin composition because of its excellent storage stability.

The component (B) and the component (C) may be contained in at least one of the liquid A and the liquid B, respectively. For example, the component (B) and the component (C) may be contained only in the liquid A or only in the liquid B. It may be included in both.

<Cured product>
The present invention includes a cured product obtained by curing the curable resin composition. In the case of a curable resin composition in which the polymer fine particles are dispersed in the state of primary particles, a cured product in which the polymer fine particles are uniformly dispersed can be easily obtained by curing the curable resin composition. Further, since the polymer fine particles are hard to swell and the viscosity of the curable resin composition is low, a cured product can be obtained with good workability.

<Application method>
The curable resin composition of the present invention can be applied by any method. It can be applied at a low temperature of about room temperature, and can be applied by heating it if necessary. The curable resin composition of the present invention is particularly useful in a method of applying by heating because it is excellent in storage stability.

The curable resin composition of the present invention can be extruded onto a substrate in a bead-like, monofilament-like or swirl-like shape using a coating robot, or a mechanical coating method such as a caulking gun or other manual coating means can be used. It can also be used. The composition can also be applied to the substrate using a jet spray method or a streaming method. The curable resin composition of the present invention is applied to one or both substrates, and the substrates are brought into contact with each other so that the composition is arranged between the substrates to be bonded, and the substrates are bonded by curing. The viscosity of the curable resin composition is not particularly limited, and is preferably about 150 to 600 Pa · s at 45 ° C. in the extruded bead method, and preferably about 100 Pa · s at 45 ° C. in the swirl coating method. In the high volume coating method using a high speed flow device, it is preferably about 20 to 400 Pa · s at 45 ° C.

When the curable resin composition of the present invention is used as an adhesive for vehicles, it is effective to increase the viscosity of the composition in order to improve the "difficulty of being washed off", and the curability of the present invention. The resin composition is preferable because it has a high thixo property and tends to have a high viscosity. The highly viscous composition can be adjusted to a viscosity that can be applied by heating.

Further, in order to improve the "difficulty of being washed off", as described in the pamphlet WO2005-118734, a polymer compound having a crystal melting point near the coating temperature of the composition is used as the curable composition of the present invention. It is preferable to blend in. The composition has a low viscosity (easy to apply) at the coating temperature and a high viscosity at the temperature in the water-washing shower step, improving "difficulty of being washed off". Examples of the polymer compound having a crystal melting point near the coating temperature include various polyester resins such as crystalline or semi-crystalline polyester polyols.

Further, as another method for improving the "difficulty of being washed off", as described in WO2006-093949 pamphlet, the curable resin composition is made into a two-component type, and amino is used as a curing agent. Examples thereof include a method in which a small amount of a curing agent capable of curing at room temperature (room temperature curing curing agent) such as an amine-based curing agent having a group or an imino group is used, and a latent curing agent such as dicyandiamide which exhibits activity at a high temperature is used in combination. By using two or more types of curing agents with significantly different curing temperatures, partial curing proceeds immediately after the composition is applied, and at the time of the water-washing shower process, the viscosity becomes high and "difficulty in being washed off" is improved. ..

<Adhesive board>
When various substrates are bonded to each other using the resin composition of the present invention, for example, wood, metal, plastic, glass and the like can be bonded. It is preferable to join the automobile parts, and it is more preferable to join the automobile frames to each other or the automobile frame and other automobile parts. Examples of the substrate include various plastic-based substrates such as steel materials such as cold-rolled steel and hot-dip zinc-plated steel, aluminum materials such as aluminum and coated aluminum, general-purpose plastics, engineering plastics, and composite materials such as CFRP and GFRP. ..

Since the curable resin composition of the present invention has excellent toughness, it is suitable for joining dissimilar substrates having different linear expansion coefficients.

Further, the curable resin composition of the present invention can also be used for joining aerospace constituent materials, particularly exterior metal constituent materials.

<Curing temperature>
The curing temperature of the curable resin composition of the present invention is not particularly limited, but when used as a one-component curable resin composition, it is preferably 50 ° C to 250 ° C, more preferably 80 ° C to 220 ° C. , 100 ° C to 200 ° C, more preferably 130 ° C to 180 ° C. When used as a two-component curable resin composition, it is not particularly limited, but is preferably 0 ° C to 150 ° C, more preferably 10 ° C to 100 ° C, further preferably 15 ° C to 80 ° C, and 20 ° C to 20 ° C. 60 ° C. is particularly preferable.

When the curable resin composition of the present invention is used as an adhesive for automobiles, the adhesive is applied to an automobile member, then a coating is applied, and the coating is baked and cured, and at the same time, the adhesive is cured. Is preferable from the viewpoint of shortening and simplifying the process.

<Use>
The composition of the present invention is preferably a one-component curable resin composition from the viewpoint of handleability.

The compositions of the present invention include structural adhesives for vehicles and aircraft, structural adhesives for wind power generation, paints, materials for laminating with glass fibers, materials for printed wiring substrates, solder resists, and interlayer insulation. Films, build-up materials, FPC adhesives, electrical insulation materials such as encapsulants for electronic components such as semiconductors and LEDs, die bond materials, underfills, semiconductor mounting materials such as ACF, ACP, NCF, NCP, liquid crystal panels, OLEDs It is preferably used as a sealing material for display devices and lighting devices such as lighting and OLED displays. In particular, it is useful as a structural adhesive for vehicles.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto, and can be appropriately modified and carried out within a range that can be adapted to the gist of the above and the following. And all of them are included in the technical scope of the present invention. In the following Examples and Comparative Examples, "parts" and "%" mean parts by mass or% by mass.

Evaluation Method First, the evaluation method of the curable resin composition produced by Examples and Comparative Examples will be described below.

[1] Measurement of Volume Average Particle Diameter The volume average particle diameter (Mv) of the polymer particles dispersed in the aqueous latex was measured using Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.). A sample diluted with deionized water was used as a measurement sample. The measurement was carried out by inputting the refractive index of water and the refractive index of each polymer particle, and adjusting the sample concentration so that the measurement time was 600 seconds and the Signal Level was within the range of 0.6 to 0.8. ..

[2] Measurement of Viscosity The viscosity of the curable resin composition was measured using a digital viscometer DV-II + Pro type manufactured by BROOKFIELD. Measured at 23 ° C. using spindle CPE-52.

1. 1. Formation of core layer Production Example 1-1; Preparation of polybutadiene rubber latex (R-1) 200 parts by mass of deionized water, 0.03 parts by mass of tripotassium phosphate, 0 potassium dihydrogen phosphate in a 100 L pressure-resistant polymerizer. .25 parts by mass, disodium ethylenediamine tetraacetate (EDTA) 0.002 parts by mass, ferrous sulfate heptahydrate (FE) 0.001 parts by mass and sodium dodecylbenzene sulfonate (SDS) 1.5 parts by mass Was charged, and after sufficient nitrogen substitution was performed while stirring to remove oxygen, 100 parts by mass of butadiene (BD) was charged into the system and the temperature was raised to 45 ° C. 0.015 parts by mass of paramentan hydroperoxide (PHP) and then 0.04 parts by mass of sodium formaldehyde sulfoxylate (SFS) were added to initiate polymerization. Four hours after the start of polymerization, 0.01 part by mass of PHP, 0.0015 part by mass of EDTA and 0.001 part by mass of FE were added. At 10 hours after the polymerization, the residual monomer was volatilized and removed under reduced pressure to complete the polymerization, and a latex (R-1) containing polybutadiene rubber particles was obtained. The volume average particle diameter of the polybutadiene rubber particles contained in the obtained latex was 0.10 μm.

Production Example 1-2; Preparation of Polybutadiene Rubber Latex (R-2) In a 100 L pressure-resistant polymerization machine, the polybutadiene rubber latex (R-1) obtained in Production Example 1-1 was placed in a solid content of 7 parts by mass and deionized water. 200 parts by mass, 0.03 parts by mass of tripotassium phosphate, 0.002 parts by mass of disodium ethylenediamine tetraacetate (EDTA), and 0.001 parts by mass of ferrous sulfate heptahydrate (FE) were added. After sufficiently replacing oxygen with stirring to remove oxygen, 93 parts by mass of butadiene (BD) was added into the system and the temperature was raised to 45 ° C. 0.02 part by mass of paramenthane hydroperoxide (PHP) and then 0.10 part by mass of sodium formaldehyde sulfoxylate (SFS) were added to initiate polymerization. Every 3 hours from the start of the polymerization to the 24th hour, 0.025 parts by mass of PHP, 0.0006 parts by mass of EDTA and 0.003 parts by mass of FE were added. At 30 hours after the polymerization, the residual monomer was volatilized and removed under reduced pressure to complete the polymerization, and a latex (R-2) containing polybutadiene rubber particles was obtained. The volume average particle diameter of the polybutadiene rubber particles contained in the obtained latex was 0.20 μm.

2. Preparation of polymer fine particles (formation of shell layer)
Production Example 2-1; Preparation of core-shell polymer latex (L-1) 1575 parts by mass (equivalent to 510 parts by mass of polybutadiene rubber particles) of latex (R-1) obtained in Production Example 1-1 and deionization in a 3L glass container. 315 parts by mass of water was charged and stirred at 60 ° C. while performing nitrogen substitution. After adding 0.024 parts by mass of EDTA, 0.006 parts by mass of FE, and 1.2 parts by mass of SFS, graft monomer (30 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 40 parts by mass of glycidyl methacrylate (GMA)) , And a mixture of 0.3 parts by mass of cumene hydroperoxide (CHP) were continuously added over 2 hours for graft polymerization. After completion of the addition, the reaction was terminated with further stirring for 2 hours to obtain a core-shell polymer latex (L-1). The volume average particle size of the core-shell polymer contained in the obtained latex was 0.11 μm.

Production Example 2-2; Preparation of core-shell polymer latex (L-2) 1575 parts by mass (equivalent to 510 parts by mass of polybutadiene rubber particles) of latex (R-2) obtained in Production Example 1-2 and deionization in a 3L glass container. 315 parts by mass of water was charged and stirred at 60 ° C. while performing nitrogen substitution. After adding 0.024 parts by mass of EDTA, 0.006 parts by mass of FE, and 1.2 parts by mass of SFS, graft monomers (40 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 15 parts by mass of glycidyl methacrylate (GMA), A mixture of 15 parts by mass of methyl methacrylate (MMA) and 0.3 parts by mass of cumene hydroperoxide (CHP) was continuously added over 2 hours for graft polymerization. After completion of the addition, the reaction was terminated with further stirring for 2 hours to obtain a core-shell polymer latex (L-2). The volume average particle size of the core-shell polymer contained in the obtained latex was 0.21 μm.

Production Example 2-3; Preparation of Core-Shell Polymer Latex (L-3) In Production Example 2-2, 40 parts by mass of <styrene (ST), 20 parts by mass of acrylonitrile (AN), and 15 parts by mass of glycidyl methacrylate (GMA) as graft monomers. Production Example 2-Except that <40 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 30 parts by mass of methyl methacrylate (MMA)> was used instead of 15 parts by mass of methyl methacrylate (MMA). The core-shell polymer latex (L-3) was obtained in the same manner as in 2. The volume average particle size of the core-shell polymer contained in the obtained latex was 0.21 μm.

Production Example 2-4; Preparation of Core-Shell Polymer Latex (L-4) In Production Example 2-2, 40 parts by mass of <styrene (ST), 20 parts by mass of acrylonitrile (AN), and 15 parts by mass of glycidyl methacrylate (GMA) as graft monomers. Production Example 2-Except that <40 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 30 parts by mass of glycidyl methacrylate (GMA)> was used instead of 15 parts by mass of methyl methacrylate (MMA). The core-shell polymer latex (L-4) was obtained in the same manner as in 2. The volume average particle size of the core-shell polymer contained in the obtained latex was 0.21 μm.

Production Example 2-5; Preparation of Core-Shell Polymer Latex (L-5) In Production Example 2-2, <styrene (ST) 40 parts by mass, acrylonitrile (AN) 20 parts by mass, glycidyl methacrylate (GMA) 15 parts by mass as graft monomers. 40 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 8 parts by mass of glycidyl methacrylate (GMA), 22 parts by mass of methyl methacrylate (MMA)> instead of 15 parts by mass of methyl methacrylate (MMA). A latex (L-5) of a core-shell polymer was obtained in the same manner as in Production Example 2-2 except that it was used. The volume average particle size of the core-shell polymer contained in the obtained latex was 0.21 μm.

Production Example 2-6; Preparation of Core-Shell Polymer Latex (L-6) In Production Example 2-2, <styrene (ST) 40 parts by mass, acrylonitrile (AN) 20 parts by mass, glycidyl methacrylate (GMA) 15 parts by mass as graft monomers. 40 parts by mass of styrene (ST), 20 parts by mass of acrylonitrile (AN), 4 parts by mass of glycidyl methacrylate (GMA), 26 parts by mass of methyl methacrylate (MMA)> instead of 15 parts by mass of methyl methacrylate (MMA). A latex (L-6) of a core-shell polymer was obtained in the same manner as in Production Example 2-2 except that it was used. The volume average particle size of the core-shell polymer contained in the obtained latex was 0.21 μm.

3. 3. Preparation of dispersion (M) in which polymer fine particles (B) are dispersed in a curable resin Production Example 3-1; Preparation of dispersion (M-1) 132 g of methyl ethyl ketone (MEK) was introduced into a 1 L mixing tank at 25 ° C. With stirring, 132 g (equivalent to 40 g of polymer fine particles) of the core-shell polymer aqueous latex (L-1) obtained in Production Examples 2-1 to 2-5 was added. After mixing uniformly, 200 g of water was added at a supply rate of 80 g / min. When the stirring was stopped promptly after the end of the supply, a slurry liquid consisting of a floating aggregate and an aqueous phase partially containing an organic solvent was obtained. Next, 360 g of the aqueous phase was discharged from the discharge port at the bottom of the tank, leaving an agglomerate containing a part of the aqueous phase. 90 g of MEK was added to the obtained aggregate and mixed uniformly to obtain a dispersion in which the core-shell polymer was uniformly dispersed. 80 g of an epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828: a liquid bisphenol A type epoxy resin) as a component (A) was mixed with this dispersion. MEK was removed from this mixture with a rotary evaporator. In this way, a dispersion (M-1) in which polymer fine particles were dispersed in an epoxy resin was obtained.

Production Example 3-2; Preparation of dispersion (M-2) In Production Example 3-1, (L-2) was used instead of (L-1) as the aqueous latex of the core-shell polymer, and it was the component (A). A dispersion (M-2) in which polymer fine particles were dispersed in the epoxy resin in the same manner as in Production Example 3-1 except that 60 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828) was mixed instead of 80 g. ) Was obtained.

Production Example 3-3; Preparation of dispersion (M-3) In Production Example 3-1, (L-3) was used as the aqueous latex of the core-shell polymer instead of (L-1), and it was the component (A). A dispersion (M-3) in which polymer fine particles were dispersed in the epoxy resin in the same manner as in Production Example 3-1 except that 60 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828) was mixed instead of 80 g. ) Was obtained.

Production Example 3-4; Preparation of Dispersion (M-4) In Production Example 3-1 using (L-2) instead of (L-1) as the aqueous latex of the core-shell polymer is used as the component (A). Production Example 3-except that 60 g of epoxy resin (A-2: manufactured by Huntsman, Araldite GY 285: liquid bisphenol F type epoxy resin) was mixed instead of 80 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828). In the same manner as in No. 1, a dispersion (M-4) in which polymer fine particles were dispersed in an epoxy resin was obtained.

Production Example 3-5; Preparation of dispersion (M-5) In Production Example 3-1 using (L-4) instead of (L-1) as the aqueous latex of the core-shell polymer is used as the component (A). A dispersion (M-5) in which polymer fine particles were dispersed in the epoxy resin in the same manner as in Production Example 3-1 except that 60 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828) was mixed instead of 80 g. ) Was obtained.

Production Example 3-6; Preparation of dispersion (M-6) In Production Example 3-1 using (L-5) instead of (L-1) as the aqueous latex of the core-shell polymer is used as the component (A). A dispersion (M-6) in which polymer fine particles were dispersed in the epoxy resin in the same manner as in Production Example 3-1 except that 60 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828) was mixed instead of 80 g. ) Was obtained.

Production Example 3-7; Preparation of Dispersion (M-7) In Production Example 3-1 using (L-6) instead of (L-1) as the aqueous latex of the core-shell polymer is used as the component (A). A dispersion (M-7) in which polymer fine particles were dispersed in the epoxy resin in the same manner as in Production Example 3-1 except that 60 g of epoxy resin (A-1: manufactured by Mitsubishi Chemical Corporation, JER828) was mixed instead of 80 g. ) Was obtained.
(Example 1, Comparative Example 1)
Each component was weighed according to the formulation shown in Table 1 and mixed well to obtain a curable resin composition.

Using each composition in Table 1, the storage stability, the T-shaped peeling adhesive strength, and the dynamic splitting resistance were measured by the following methods. The results are shown in Table 1.

<Storage stability>
Before and after storing the curable resin composition at 40 ° C. for 14 days, the viscosity at a Shear Rate of 2 (s- ¹ ) was measured. As the storage stability, the value of "viscosity of 2 (s ^-1 ) after storage when the viscosity of 2 (s ^-1 ) before storage was 100" was measured. The larger this value is, the worse the storage stability is. The test results are shown in Table 1.

<T-shaped peeling adhesive strength>
The curable resin composition was applied to two SPCC steel sheets having dimensions: 25 × 200 × 0.5 mm, superposed so as to have an adhesive layer thickness of 0.25 mm, and cured at 170 ° C. × 1 hour. The T-shaped peel-off adhesive strength at 23 ° C. was measured according to JIS K6854. The test results are shown in Table 1.

<Dynamic split resistance (impact peeling adhesiveness)>
The curable resin composition was applied to two SPCC steel sheets, laminated so as to have an adhesive layer thickness of 0.25 mm, cured under the condition of 170 ° C. × 1 hour, and dynamically split at 23 ° C. according to ISO 11343. The resistance was measured. The test results are shown in Table 1.

The various compounding agents shown in Table 1 were used.
<Epoxy resin (A)>
A-1: JER828 (manufactured by Mitsubishi Chemical Corporation, bisphenol A type epoxy resin liquid at room temperature, epoxy equivalent: 184 to 194)
<Dispersion (M) in which polymer fine particles (B) are dispersed in epoxy resin (A)>
M-1: Dispersion obtained in Production Example 3-1 <Surface-treated calcium oxide>
CML # 31 (manufactured by Omi Chemical Industry, calcium oxide surface-treated with fatty acids)
≪Untreated calcium oxide≫
CML # 35 (manufactured by Omi Chemical Industry, surface-untreated calcium oxide)
≪Epoxy reactive diluent (monoepoxide) ≫
Cardula E10P (Momentive, Versatic Acid Glycidyl Ester)
≪Humed silica≫
CAB-O-SIL TS-720 (manufactured by CABOT, fumed silica surface-treated with polydimethylsiloxane),
≪Wollast Night≫
NYAD 400 (manufactured by NYCO Minerals, average fiber length: 35 μm, average fiber diameter: 7 μm)
≪Carbon black≫
MONARCH 280 (manufactured by Cabot)
<Epoxy curing agent (D)>
Dyhard 100S (manufactured by AlzChem, dicyandiamide)
<Curing accelerator (E)>
Dyhard UR300 (manufactured by AlzChem, 1,1-dimethyl-3-phenylurea)

From Table 1, the curable resin composition containing the component (A), the component (B), and the component (C) of the present invention has good storage stability (small change in viscosity) and peeling adhesiveness. It can be seen that it has excellent impact resistance and peeling adhesiveness. The amount of the component (A) contained in the curable resin composition in Table 1 is the sum of the component added as the epoxy resin and the component contained in the dispersion (M) of the polymer fine particles.

(Examples 2 to 10, Comparative Examples 2 to 3)
Each component was weighed according to the formulation shown in Table 2 and mixed well to obtain a curable resin composition.

Using each composition in Table 2, storage stability and dynamic splitting resistance were measured by the following methods. The results are shown in Table 2.

<Storage stability>
Before and after storing the curable resin composition at 40 ° C. for 7 days, the viscosity at a Shear Rate of 1 (s- ¹ ) was measured. As the storage stability, the value of "viscosity of 1 (s ^-1 ) after storage when the viscosity of 1 (s ^-1 ) before storage was 100" was measured. The larger this value is, the worse the storage stability is. The test results are shown in Table 2.

<Dynamic split resistance (impact peeling adhesiveness)>
The curable resin composition was applied to two SPCC steel sheets, laminated so as to have an adhesive layer thickness of 0.25 mm, cured under the condition of 155 ° C. × 25 minutes, and dynamically split at 23 ° C. according to ISO 11343. The resistance was measured. The test results are shown in Table 2.

As a compounding agent other than the above-mentioned various compounding agents, those shown below were used.
<Epoxy resin (A)>
A-2: Araldite GY 285 (manufactured by Huntsman, liquid bisphenol F type epoxy resin, epoxy equivalent: 164 to 172)
A-3: JER1001 (manufactured by Mitsubishi Chemical Corporation, bisphenol A type solid epoxy resin having a softening point of 64 ° C. by the ring and ball method, epoxy equivalent: 450 to 500)
A-4: Epolite 400P (manufactured by Kyoeisha Chemical Co., Ltd., polypropylene glycol diglycidyl ether, epoxy equivalent: 300 to 330)
<Dispersion (M) in which polymer fine particles (B) are dispersed in epoxy resin (A)>
M-2 to 4: Dispersion obtained in Production Examples 3 to 2 to 4 << Rubber-modified epoxy resin >>
EPON Resin 58005 (Momentive, rubber-modified epoxy resin, elastomer concentration: 40 wt%, bisphenol A type epoxy resin concentration: 60 wt%, epoxy equivalent: 325-375)
≪Blocked urethane≫
QR-9466 (made by ADEKA, blocked urethane, block NCO equivalent: 220)
≪Untreated light calcium carbonate≫
Silver-W (manufactured by Shiraishi Kogyo, surface-untreated light calcium carbonate, average particle diameter (major diameter): 1.5 μm)
≪Untreated heavy calcium carbonate≫
Whiten SB (made of Shiraishi calcium, surface-untreated heavy calcium carbonate, average particle size: 1.8 μm)
≪Surface treatment heavy calcium carbonate≫
Ryton A (made of Shiraishi calcium, heavy calcium carbonate surface-treated with modified fatty acids, average particle size: 1.8 μm)

From Table 2, the curable resin composition containing the component (A), the component (B), and the component (C) of the present invention has good storage stability (small change in viscosity) and impact-resistant peeling. It can be seen that it has excellent adhesiveness. The amount of the component (A) contained in the curable resin composition in Table 2 is contained in the component added as the epoxy resin, the component contained in the dispersion (M) of the polymer fine particles, and the rubber-modified epoxy resin. It is the amount obtained by adding the components.

(Examples 11 to 15)
Each component was weighed according to the formulation shown in Table 3 and mixed well to obtain a curable resin composition.

Using each composition in Table 3, the storage stability, the T-shaped peeling adhesive strength, and the dynamic splitting resistance were measured by the following methods. The results are shown in Table 3.

<Storage stability>
Before and after storing the curable resin composition at 40 ° C. for 7 days, the viscosity at a Shear Rate of 1 (s- ¹ ) was measured. As the storage stability, the value of "viscosity of 1 (s ^-1 ) after storage when the viscosity of 1 (s ^-1 ) before storage was 100" was measured. The larger this value is, the worse the storage stability is. The test results are shown in Table 3.

<T-shaped peeling adhesive strength>
The curable resin composition was applied to two SPCC steel sheets having dimensions: 25 × 200 × 0.5 mm, superposed so as to have an adhesive layer thickness of 0.25 mm, and cured under the conditions of 170 ° C. × 40 minutes. The T-shaped peel-off adhesive strength at 23 ° C. was measured according to JIS K6854. The test results are shown in Table 3.

<Dynamic split resistance (impact peeling adhesiveness)>
The curable resin composition was applied to two SPCC steel sheets, laminated so as to have an adhesive layer thickness of 0.25 mm, cured under the condition of 170 ° C. × 40 minutes, and dynamically split at 23 ° C. according to ISO 11343. The resistance was measured. The test results are shown in Table 3.

As a compounding agent other than the above-mentioned various compounding agents, those shown below were used.
<Dispersion (M) in which polymer fine particles (B) are dispersed in epoxy resin (A)>
M-5-7: Dispersion obtained in Production Examples 3-5-7 << Rubber-modified epoxy resin >>
HyPox RA1340 (CVC, rubber-modified epoxy resin, elastomer concentration: 40 wt%, bisphenol A type epoxy resin concentration: 60 wt%, epoxy equivalent: 325-375)

From Table 3, the curable resin composition containing the component (A), the component (B), and the component (C) of the present invention has good storage stability (small change in viscosity) and peeling adhesiveness. It can be seen that it has excellent impact resistance and peeling adhesiveness. The amount of the component (A) contained in the curable resin composition in Table 3 is contained in the component added as the epoxy resin, the component contained in the dispersion (M) of the polymer fine particles, and the rubber-modified epoxy resin. It is the amount obtained by adding the components.

Claims (17)

Curable resin composition containing 1 to 100 parts by mass of polymer fine particles (B) having a core-shell structure and 0.1 to 10 parts by mass of surface-treated calcium oxide (C) with respect to 100 parts by mass of the epoxy resin (A). (However, the epoxy resin (A) excludes rubber-modified epoxy resin and urethane-modified epoxy resin) . The curable resin composition according to claim 1 , wherein the surface treatment agent for the component (C) is a fatty acid. (C) The curable resin composition according to claim 1 or 2, wherein the content of untreated calcium oxide is 20 parts by mass or less with respect to 100 parts by mass of the component. (C) The curable resin composition according to any one of claims 1 to 3, wherein the surface-untreated calcium oxide is substantially not contained in 100 parts by mass of the component. The curable resin composition according to any one of claims 1 to 4, wherein the epoxy curing agent (D) is further contained in an amount of 1 to 80 parts by mass with respect to 100 parts by mass of the component (A). The curable resin composition according to any one of claims 1 to 5, further containing 0.1 to 10 parts by mass of the curing accelerator (E) with respect to 100 parts by mass of the component (A). .. Any of claims 1 to 6, wherein the component (B) has one or more core layers selected from the group consisting of a diene-based rubber, a (meth) acrylate-based rubber, and a polysiloxane-based rubber. The curable resin composition according to. The curable resin composition according to claim 7, wherein the diene-based rubber is a butadiene rubber and / or a butadiene-styrene rubber. The component (B) has a shell layer formed by graft-polymerizing one or more monomer components selected from the group consisting of aromatic vinyl monomer, vinyl cyan monomer, and (meth) acrylate monomer into a core layer. The curable resin composition according to any one of claims 1 to 8. The curable resin composition according to any one of claims 1 to 9, wherein the component (B) has a shell layer obtained by graft-polymerizing a monomer component having an epoxy group onto a core layer. The curable resin composition according to claim 10, wherein the content of the epoxy group in the component (B) is 0.01 to 0.8 mmol / g. The curable resin composition according to any one of claims 1 to 11, wherein the component (B) is dispersed in the curable resin composition in the form of primary particles. The curable resin composition according to any one of claims 1 to 12, wherein 1 to 100 parts by mass of surface-treated calcium carbonate is further contained with respect to 100 parts by mass of the component (A). A cured product obtained by curing the curable resin composition according to any one of claims 1 to 13. A one-component curable resin composition comprising the curable resin composition according to any one of claims 1 to 13. A structural adhesive using the curable resin composition according to any one of claims 1 to 13. A structural adhesive for vehicles using the curable resin composition according to any one of claims 1 to 13.