JP2006143759A - Two-part room temperature-curable epoxy resin composition and metal adhesive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-part room temperature-curable epoxy resin composition which exhibits excellent adhesiveness at room temperature, maintains the adhesiveness even at elevated temperatures, and is particularly excellent in adhesiveness to metal. <P>SOLUTION: The two-part room temperature-curable epoxy resin composition comprises a main component which is liquid at room temperature and comprises an epoxy resin composed of a difunctional epoxy resin and a trifunctional epoxy resin, wherein the trifunctional epoxy resin is contained in an amount of 30 mass% or more, and a curing agent comprising an aliphatic amine compound and/or an alicyclic amine compound, dicyandiamide and an imidazole compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a two-pack type room temperature curable epoxy resin composition. The present invention also relates to a metal adhesive composition comprising this two-pack type room temperature curable epoxy resin composition.

  A two-component room temperature curable epoxy resin composition composed of a liquid epoxy resin and a curing agent such as a liquid amine compound or mercaptan, and used by mixing just before using the main agent and the curing agent, It can be cured at room temperature, can be used without solvent, has no gas generation during curing, and has excellent properties such as cured materials. Adhesive materials, paints, primers, casting materials, fiber reinforced composite matrix resins It is used for such applications.

In particular, in the civil engineering field, liquid epoxy resin is used to repair concrete structures such as bridges, tunnels, and buildings over time, to repair damage caused by earthquakes, and to reinforce earthquake resistance standards for larger earthquakes. The method used is used.
For example, a reinforcing method is known in which a steel plate is attached to the surface of a reinforcing portion using a resin. However, since this method uses a steel plate, the repair / reinforcement portion becomes heavy, and defects such as peeling of the adhesive surface may occur. Moreover, depending on the construction location, it may become high temperature by being exposed to direct sunlight, and the adhesiveness may be lowered when left under such high temperature.

  In addition, the two-pack type room temperature curable epoxy resin composition has excellent electrical insulation properties, heat resistance, and other characteristics, and since there is no need for heating, it can reduce the residual stress generated at the joint. It is possible to remove distortion necessary for welding and putty work before painting, etc., so it can be used in fields related to electrical and electronic materials because it can improve workability. I came. However, with the recent development of the electric and electronic materials field, epoxy resin compositions are required to have a high level of performance, and have superior adhesion to metal members and even at high temperatures. A room temperature curable epoxy resin composition that can be maintained is desired.

  On the other hand, as a two-pack type room temperature curable epoxy resin composition, for example, a matrix resin composition having a high cured reinforcing sheet tensile strength retention rate and adhesion strength retention rate even at 60 ° C. while being a room temperature curing type is provided. A matrix resin composition for fiber reinforcement of concrete structures is proposed, which contains an epoxy resin as a main agent and primary amine-based curing agent and imidazole-based curing agent as a curing agent component in a specific ratio. (See Patent Document 1).

  An epoxy resin containing (A) an epoxy resin, (B) an amine-based curing agent, and (C) a curing accelerator for the purpose of providing a cured product that is inexpensive, soft, and excellent in resistance to tensile elongation. An epoxy resin composition containing 80% by weight or more of a flexible epoxy resin in the epoxy resin as component (A) has been proposed (see Patent Document 2).

JP 2000-109578 A Japanese Patent Laid-Open No. 11-60697

However, as a result of intensive studies by the inventors, the matrix resin composition for fiber reinforcement described in Patent Document 1 may not have sufficient adhesion at room temperature, and there is room for improvement in adhesion. I understood.
Moreover, not only the composition of patent document 1, but an epoxy resin composition generally has the property of being hard and brittle, Therefore The improvement of toughness is requested | required.
The epoxy resin composition described in Patent Document 2 contains 80% by weight or more of a flexible epoxy resin in the epoxy resin of component (A), and the cured product is too soft. It is difficult in practice. In the examples, 2-ethyl-4-methylimidazole or 1,8-diazabicyclo (5,4,0) undecene-7 (DBU) is used as a curing accelerator. However, even when such a curing accelerator is used, the adhesiveness at room temperature may not be sufficient as in the composition of Patent Document 1.

  An object of the present invention is to provide a two-pack type room temperature curable epoxy resin composition that exhibits excellent adhesion at room temperature, can maintain adhesion even at high temperatures, and is particularly excellent in adhesion to metals.

As a result of intensive studies, the inventor has found that a main agent containing an epoxy resin composed of a specific proportion of a bifunctional epoxy resin and a trifunctional epoxy resin, an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide, By using a curing agent containing an imidazole compound, a two-pack type room temperature curable epoxy resin that exhibits excellent adhesion at room temperature, can maintain adhesion even at high temperatures, and is particularly excellent in adhesion to metals It was found to be a composition.
That is, the present invention provides the following (1) to (4).

(1) A main agent comprising a bifunctional epoxy resin and a trifunctional epoxy resin, containing 30 mass% or more of the trifunctional epoxy resin, and containing an epoxy resin that is liquid at room temperature;
A two-pack room temperature curable epoxy resin composition comprising a curing agent containing an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide, and an imidazole compound.

(2) The content of the amine compound is an amount such that active hydrogen of the amine compound is 0.6 to 1.0 equivalent with respect to an epoxy group of the epoxy resin,
The dicyandiamide content is 0.1 to 2.0 parts by mass with respect to 100 parts by mass of the epoxy resin,
The two-component room temperature curable epoxy resin composition according to (1), wherein the content of the imidazole compound is 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the epoxy resin.

  (3) The main agent and / or the curing agent further comprises a core made of a (meth) acrylate polymer having a glass transition temperature of −30 ° C. or lower, and a (meth) acrylate heavy having a glass transition temperature of 70 ° C. or higher. The two-pack type room temperature curable epoxy resin composition according to the above (1) or (2), which contains a core-shell type powdery polymer composed of a shell made of coalescence.

  (4) A metal adhesive composition comprising the two-component room temperature curable epoxy resin composition according to any one of (1) to (3) above.

The two-pack type room temperature curable epoxy resin composition of the present invention exhibits excellent adhesion at room temperature, can maintain adhesion even at high temperatures, and is particularly excellent in adhesion to metals. Furthermore, when it contains a core-shell type powdery polymer, it has excellent toughness in addition to the above characteristics.
In addition, the metal adhesive composition of the present invention exhibits excellent adhesiveness at room temperature and can maintain adhesiveness even at high temperatures. Furthermore, when it contains a core-shell type powdery polymer, it has excellent toughness in addition to the above characteristics.

Hereinafter, the present invention will be described in detail.
The two-pack type room temperature curable epoxy resin composition of the present invention (hereinafter also referred to as “the composition of the present invention”) is composed of a bifunctional epoxy resin and a trifunctional epoxy resin, and 30 masses of the above trifunctional epoxy resin. % Or more of a main agent containing an epoxy resin that is liquid at room temperature, an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide, and a curing agent containing an imidazole compound.
Here, in this specification, “normal temperature” means about −5 to 40 ° C.

<Epoxy resin>
The epoxy resin used for the main ingredient of the composition of the present invention is an epoxy resin which is composed of a bifunctional epoxy resin and a trifunctional epoxy resin and contains 30% by mass or more of the trifunctional epoxy resin at room temperature.
Since the epoxy resin contains a bifunctional epoxy resin and a trifunctional epoxy resin in the above ratio, the cured product of the composition of the present invention has appropriate flexibility and toughness, excellent heat resistance, and high temperature. Adhesiveness can be maintained even underneath. Hereinafter, for the sake of convenience, the property capable of maintaining the adhesiveness at high temperature is referred to as “high temperature resistance”.
Since it is excellent in the balance of these characteristics, it is preferable to contain 30-99 mass% of trifunctional epoxy resins in the said epoxy resin, and 40-90 mass% is more preferable. As the epoxy resin, only a trifunctional epoxy resin may be used particularly when it is used for an application requiring high-temperature adhesiveness.

The bifunctional epoxy resin is not particularly limited as long as it is a compound having two epoxy groups in one molecule. Specifically, for example, bisphenol type epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, diphenylfluorene type epoxy resin and the like can be mentioned. It is done. These may be used alone or in combination of two or more.
Among these, the bisphenol-type epoxy resin is preferable from the viewpoint of low viscosity and excellent curability and adhesiveness.

The bifunctional epoxy resin preferably has an epoxy equivalent of 180 to 300 in terms of good workability due to low viscosity and good heat resistance of the cured product, and 180 to 200. Is more preferable.
The bifunctional epoxy resin may be a commercially available product or may be produced. The production conditions are not particularly limited, and can be performed under conditions usually used.

The trifunctional epoxy resin is not particularly limited as long as it is a compound having three epoxy groups in one molecule. Specifically, for example, phenol novolac type epoxy resin, cresol novolac type epoxy resin, glycidylamine type epoxy resin such as triglycidylaminophenol, triglycidylaminocresol, tetrakis (glycidyloxyphenyl) ethane, tris (glycidyloxy) methane And glycidyl ether type epoxy resins. These may be used alone or in combination of two or more.
Of these, glycidylamine type epoxy resins are preferred because of their low viscosity and excellent curability.

The trifunctional epoxy resin preferably has an epoxy equivalent of 90 to 180 in terms of good workability due to low viscosity and good heat resistance of the cured product.
The trifunctional epoxy resin may be a commercially available product or may be manufactured. The production conditions are not particularly limited, and can be performed under conditions usually used.

  The combination of the bifunctional epoxy resin and the trifunctional epoxy resin is not particularly limited, but it is low viscosity and curable to use a bisphenol type epoxy resin as the bifunctional epoxy resin and a glycidylamine type epoxy resin as the trifunctional epoxy resin. Further, it is preferable from the viewpoint of excellent adhesiveness.

  The composition of the present invention may contain an epoxy resin other than those described above. For example, a tetrafunctional or higher polyfunctional epoxy resin can be used.

<Amine compound>
The amine compound used in the composition of the present invention is an aliphatic amine compound and / or an alicyclic amine compound, and is used as a curing agent for the epoxy resin. Since the amine compound has a highly reactive amino group, the reaction with the epoxy group of the epoxy resin proceeds promptly even at room temperature. Moreover, an aliphatic amine compound and an alicyclic amine compound are excellent in the physical property of hardened | cured material.

  The aliphatic amine compound is not particularly limited as long as it is an aliphatic amine compound having at least one amino group or imino group. Specifically, for example, n-propylamine, n-butylamine, s-butylamine, tert-butylamine, polyoxypropyleneamine, ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, dimethylaminopropylamine, 2-diethylaminoethylamine, 3-diethylaminopropylamine, 2-butyl-2-ethylpentane-1,5-diamine, 3- (2-aminoethyl) aminopropylamine, 3-amino-1-methylaminopropane, 3- Aminopropanol, 4,7-dioxadecane-1,10-diamine, 4,9-dioxadecane-1,12-diamine, dipropylenetriamine, 2-ethylhexylamine, n-hexylamine, 2-methoxyethylamine, 3-methoxypropyl Amine, 3 Methylaminopropylamine, neopentanediamine, n-octylamine, tridecylamine, 4,7,10-trioxatridecane-1,13-diamine, 2,2,4-trimethylhexamethylenediamine, 1,6- Hexamethylenediamine, 1,12-dodecanediamine, 1,10-decanediamine, 1,8-octanediamine, 1,14-tetradecanediamine, 1,16-hexadecanediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, etc. An aliphatic ring compound such as xylylenediamine; and a modified product thereof.

  The alicyclic amine compound is not particularly limited as long as it is an alicyclic amine compound having at least one amino group or imino group. Specifically, for example, cyclohexylamine, 3-amino-1-cyclohexylaminopropane, 4,4′-diaminodicyclohexylmethane, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, cyclohexylaminopropylamine, 1,3-bis (aminomethyl) cyclohexane, 2,5 (2,6) -bis (aminomethyl) bicyclo [2.2.1] heptane, aminocaprolactam, 1,3-bisaminomethylcyclohexane (1,3 -BAC), norbornane diamine (NBDA), isophorone diamine (IPDA) and the like; and modified products thereof.

  Specifically, as the modified body, for example, an epoxy adduct obtained by reacting an excess of the amine compound with an epoxy resin and consuming all of the epoxy compound; the amine compound, acrylic acid, and methacrylic acid A Michael adduct obtained by reacting a vinyl monomer such as an ester thereof and acrylonitrile; a Mannich modified product obtained by reacting the amine compound, formaldehyde and a phenol compound; the amine compound and urea or Examples include urea-modified products obtained by deammonia reaction with thiourea. Among these, a Mannich modified product is preferably used because of its excellent curability.

The said amine compound may be used independently and may use 2 or more types together.
Among these, aromatic ring-containing aliphatic amine compounds, alicyclic amine compounds, and modified products thereof are preferable from the viewpoint of whitening resistance and curability. In particular, those having at least one amino group are preferred from the viewpoint of excellent reactivity with an epoxy resin and physical properties of a cured product.

  The content of the amine compound (when the aliphatic amine compound and the alicyclic amine compound are used in combination means the total. The same shall apply hereinafter) is such that the active hydrogen of the amine compound is based on the epoxy group of the epoxy resin. The amount is preferably 0.6 to 1.0 equivalent. Within this range, the curing rate is high, and the resulting cured product is excellent in heat resistance and high temperature resistance. From the point which is excellent by these characteristics, it is more preferable that it is the quantity used as 0.8-0.95 equivalent with respect to the epoxy group of the said epoxy resin.

<Dicyandiamide>
The dicyandiamide used in the composition of the present invention performs a curing catalyst function and an adhesion imparting function. Although the mechanism by which dicyandiamide imparts adhesiveness is not clear, dicyandiamide has a high polarity and is considered to interact with an oxide on the surface of an adherend, for example, a metal material. Furthermore, it is possible to exhibit an extremely excellent metal adhesion that has not been achieved by a synergistic effect with an imidazole compound described later.

  The content of dicyandiamide is preferably 0.1 to 2.0 parts by mass with respect to 100 parts by mass of the epoxy resin. When the content is within this range, the cured product is excellent in heat resistance and excellent in high temperature resistance. From the point which is excellent by these characteristics, it is more preferable that it is 0.5-1.5 mass parts with respect to 100 mass parts of said epoxy resins.

<Imidazole compound>
The imidazole compound used in the composition of the present invention fulfills a curing catalyst function and an adhesion-imparting function as in the case of the above-described dicyandiamide.
Although it does not specifically limit as said imidazole compound, Specifically, for example, 2-methylimidazole, 1,2-dimethylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1-isobutyl 2-methylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 2,4-diamino-6 (2′-methylimidazole (1 ′)) ethyl-s-triazine, 2,4-diamino- 6 (2'-undecylimidazole ( ′)) Ethyl-s-triazine, 2,4-diamino-6 (2′-ethyl, 4-methylimidazole (1 ′)) ethyl-s-triazine, 2,4-diamino-6 (2′-methylimidazole) (1 ′)) ethyl-s-triazine isocyanuric acid adduct, 2-methylimidazole isocyanuric acid 2: 3 adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-3,5-dihydroxymethylimidazole, Various imidazoles such as 2-phenyl-4-hydroxymethyl-5-methylimidazole and 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole, and these imidazoles and phthalic acid, isophthalic acid, terephthalic acid Acid, trimellitic acid, pyromellitic acid, naphthalenedicarboxylic acid, male Phosphate, and salts such as the polycarboxylic acid such as oxalic acid is. These may be used alone or in combination of two or more.

  The content of the imidazole compound is preferably 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the epoxy resin. When the content is within this range, the cured product is excellent in heat resistance and excellent in high temperature resistance. From the point which is excellent by these characteristics, it is more preferable that it is 0.5-3.0 mass parts with respect to 100 mass parts of said epoxy resins.

The combination of content of each component mentioned above is demonstrated.
The content of the amine compound is such that the active hydrogen of the amine compound is 0.6 to 1.0 equivalent with respect to the epoxy group of the epoxy resin, and the content of dicyandiamide is 100 parts by mass of the epoxy resin. It is 0.1-2.0 mass parts with respect to it, and it is preferable that content of an imidazole compound is 0.1-5.0 mass parts with respect to 100 mass parts of said epoxy resins.

  In general, amine compounds are highly reactive and react rapidly with epoxy groups even at room temperature, but their cured products have a problem of poor adhesion at high temperatures because their heat resistance is not high. On the other hand, as a result of intensive studies by the present inventor, it has been found that when the amine compound, dicyandiamide and imidazole compound are used in combination, the adhesiveness at high temperature, particularly the metal adhesiveness, is improved. In particular, when the content of each component is within the above range, the composition is more excellent in adhesiveness and metal adhesiveness at high temperatures.

<Core-shell type powdery polymer>
The composition of the present invention further includes a core made of a (meth) acrylate polymer having a glass transition temperature of −30 ° C. or lower and a shell made of a (meth) acrylate polymer having a glass transition temperature of 70 ° C. or higher. It is preferable to contain the comprised core-shell type powdery polymer. By containing the core-shell type powdery polymer having such a configuration, a composition excellent in toughness of the cured product can be obtained.

  The core (meth) acrylate polymer is composed of a rubbery polymer having a glass transition temperature of −30 ° C. or less, and the shell (meth) acrylate polymer is a glassy polymer having a glass transition temperature of 70 ° C. or higher. It consists of

The core-shell type powdery polymer can be produced, for example, by a continuous multi-stage seed emulsion polymerization method having at least two stages.
First, in the first stage polymerization, a (meth) acrylate monomer having an alkyl group having 2 to 8 carbon atoms, preferably a (meth) acrylate monomer and a crosslinkable monomer. A rubbery seed polymer having a glass transition temperature of −30 ° C. or lower is prepared by polymerization. Specific examples of the (meth) acrylate monomer having an alkyl group having 2 to 8 carbon atoms include, for example, ethyl acrylate, propyl acrylate, n-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, and ethyl methacrylate. And butyl methacrylate. These may be used alone or in combination of two or more.

Moreover, as the crosslinkable monomer, a compound having two or more double bonds having substantially the same reactivity can be used. Specifically, for example, ethylene glycol diacrylate, ethylene glycol dimethacrylate, butylene glycol diacrylate, butylene glycol dimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate Hexanediol diacrylate, hexanediol methacrylate, oligoethylene diacrylate, oligoethylene dimethacrylate, and the like. Furthermore, aromatic divinyl monomers such as divinylbenzene, triallyl trimellitic acid, triallyl isocyanurate, etc. are also used. be able to. These may be used alone or in combination of two or more.
Further, the amount used is appropriately selected in the range of usually 0.01 to 5% by mass, preferably 0.1 to 2% by mass, based on the total mass of the monomers.

In addition to the (meth) acrylate monomer and the crosslinkable monomer, other monomers that can be copolymerized may be used as desired. Specific examples of the other copolymerizable monomer include aromatic vinyl compounds such as styrene, vinyl toluene and α-methyl styrene, vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, Examples include vinylidene cyanide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxybutyl acrylate, 2-hydroxyethyl fumarate, hydroxybutyl vinyl ether, monobutyl maleate, glycidyl methacrylate, and butoxyethyl methacrylate. These may be used alone or in combination of two or more.
The amount used is usually selected in the range of 50 mass% or less with respect to the total mass of the monomers.

Next, the (meth) acrylate polymer particle thus obtained is used as a core, and a (meth) acrylate monomer having an alkyl group having 1 to 4 carbon atoms, a crosslinkable monomer, Is used for the second stage emulsion polymerization in which a shell is formed by graft copolymerization. In this case, specific examples of the (meth) acrylate monomer having an alkyl group having 1 to 4 carbon atoms used include ethyl acrylate, n-butyl acrylate, methyl methacrylate, and butyl methacrylate. . These may be used alone or in combination of two or more. Among these, methyl methacrylate is preferable.
The glass transition temperature of the (meth) acrylate polymer forming the shell is 70 ° C. or higher. When the temperature is 70 ° C. or higher, the composition has excellent storage stability and does not cause nozzle clogging when spray drying.

Moreover, as this crosslinkable monomer, it can select and use 1 type (s) or 2 or more types from what was illustrated in description of the (meth) acrylate type polymer which forms the said core.
The amount of the crosslinkable monomer used is usually 0.01 to 10% by mass, preferably 0.1 to 5% by mass, based on the total mass of the monomer. In addition to the (meth) acrylate monomer and the crosslinkable monomer, other monomers that can be copolymerized can be used as desired. As this other copolymerizable monomer, one or more kinds selected from those exemplified in the description of the (meth) acrylate polymer forming the core can be used.
The amount used is usually selected in the range of 50% by mass or less based on the total monomer mass.

  A latex containing a core-shell type polymer obtained by such multi-stage seed emulsion polymerization is usually directly spray-dried to obtain a core-shell type powder polymer excellent in dispersibility in an epoxy resin. As described above, this core-shell type powdery polymer can be obtained by at least two-stage multi-stage seed emulsion polymerization method. However, in some cases, the seed latex prepared in the first stage is partially agglomerated, It may be prepared by graft polymerization on the top. There are many known methods for secondary aggregation, and any of them may be used. Further, after emulsion polymerization, latex particles are coagulated and separated by a salt folding method or a freezing method, and a wet cake prepared by dehydration can be dried in a fluidized bed or the like to obtain aggregated particles.

  In the core-shell type powdered polymer thus obtained, the core content is preferably 20 to 80% by mass and the shell content is preferably in the range of 80 to 20% by mass. When the content of each component is within this range, the effect of imparting toughness is excellent. Further, since the core can be completely covered with the shell, when mixed with the epoxy resin, the viscosity change over time of the entire system does not increase and the toughness imparting effect does not vary.

The average particle size of the core is preferably 0.1 to 3.0 μm. When the average particle size is within this range, the dispersibility with respect to the matrix is excellent, so that the resulting composition has excellent mechanical strength and storage stability.
The average thickness of the shell is preferably 50 mm or more. If it is 50 mm or more, the covering property of the core is sufficient, and the storage stability is excellent.

  In the composition of the present invention, the content of the core-shell type powdery polymer is 10 to 100 parts by mass, preferably 10 to 50 parts by mass with respect to 100 parts by mass of the epoxy resin. Within this range, a composition having excellent toughness, a viscosity that does not become too high, and excellent handleability can be obtained.

<Additives>
The composition of the present invention includes, in addition to the above-described components, a curing catalyst, a filler, a plasticizer, an antioxidant, an anti-aging agent, a pigment, a thixotropy imparting agent, and adhesiveness, as long as the object of the present invention is not impaired. Various additives such as an imparting agent, a flame retardant, a dye, an antistatic agent, a dispersant, and a solvent can be contained. As the various additives, commonly used ones can be used. Hereinafter, a part thereof will be specifically exemplified, but it is not limited to those exemplified.

  As the curing catalyst, a known catalyst excluding the above dicyandiamide and the above imidazole compound can be used. Specifically, for example, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) Phenol, tertiary amines such as 1,8-diaza-bicyclo (5,4,0) undecene-7, phosphines such as triphenylphosphine, metal compounds such as tin octylate, quaternary phosphonium salts, etc. Can be mentioned.

  Examples of the filler include organic or inorganic fillers having various shapes. Specifically, for example, fumed silica, calcined silica, precipitated silica, ground silica, fused silica; diatomaceous earth; iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide; calcium carbonate, magnesium carbonate, zinc carbonate; Waxite clay, kaolin clay, calcined clay; carbon black; these fatty acid treated products, resin acid treated products, urethane compound treated products, fatty acid ester treated products, and the like. The content of the filler is preferably 90% by mass or less in the entire composition in terms of physical properties of the cured product.

  Specific examples of the plasticizer include dioctyl phthalate (DOP) and dibutyl phthalate (DBP); dioctyl adipate, isodecyl succinate; diethylene glycol dibenzoate, pentaerythritol ester; butyl oleate, methyl acetylricinoleate; phosphorus Examples include tricresyl acid, trioctyl phosphate; propylene glycol polyester adipate, butylene glycol polyester adipate, and the like. These may be used alone or in combination of two or more. It is preferable that content of a plasticizer is 50 mass parts or less with respect to 100 mass parts of said epoxy resins from a viewpoint of workability | operativity.

Specific examples of the antioxidant include butylhydroxytoluene (BHT) and butylhydroxyanisole (BHA).
Specific examples of the anti-aging agent include hindered phenol compounds.

  Specific examples of the pigment include inorganic pigments such as titanium oxide, zinc oxide, ultramarine, bengara, lithopone, lead, cadmium, iron, cobalt, aluminum, hydrochloride, sulfate, etc .; azo pigment, phthalocyanine pigment, quinacridone Pigment, quinacridone quinone pigment, dioxazine pigment, anthrapyrimidine pigment, ansanthrone pigment, indanthrone pigment, flavanthrone pigment, perylene pigment, perinone pigment, diketopyrrolopyrrole pigment, quinonaphthalone pigment, anthraquinone pigment, thioindigo pigment, benzimidazolone Examples thereof include organic pigments such as pigments, isoindoline pigments, and carbon black.

  Specific examples of the thixotropic agent include aerosil (manufactured by Nippon Aerosil Co., Ltd.), disparon (manufactured by Enomoto Kasei Co., Ltd.), and the like.

  Specific examples of the adhesion-imparting agent include known silane coupling agents, silane compounds having an alkoxysilyl group, titanium coupling agents, zirconium coupling agents, terpene resins, phenol resins, terpene-phenol resins, Examples include rosin resins and xylene resins. More specifically, for example, trimethoxyvinylsilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like can be mentioned.

  Specific examples of the flame retardant include chloroalkyl phosphate, dimethyl / methyl phosphonate, bromine / phosphorus compound, ammonium polyphosphate, neopentyl bromide-polyether, brominated polyether, and the like.

  Examples of the antistatic agent generally include quaternary ammonium salts; hydrophilic compounds such as polyglycols and ethylene oxide derivatives.

  The composition of this invention can be manufactured by a well-known method. For example, in a nitrogen atmosphere, an epoxy resin, an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide, an imidazole compound, an optionally added core-shell powdered polymer, and an additive are mixed using a stirrer. And can be obtained by dispersing.

  The composition of the present invention can be used as a two-pack type comprising a main agent containing an epoxy resin and a curing agent containing an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide and an imidazole compound. The core-shell type powdery polymer and the additive that are optionally added can be contained in one or both of the main agent and the curing agent.

  The two-pack type room temperature curable epoxy resin composition of the present invention thus obtained exhibits excellent adhesion at room temperature, can maintain adhesion even at high temperatures, and is particularly excellent in adhesion to metals. Furthermore, when it contains a core-shell type powdery polymer, it has excellent toughness in addition to the above characteristics.

  The two-pack type room temperature curable epoxy resin composition of the present invention has excellent properties as described above, and is therefore used for sealing materials, coating films, adhesives, prepregs, paints, rust preventive paints, sealing agents, etc. Can be suitably used. In particular, it can be suitably used as a metal adhesive.

The metal adhesive composition of the present invention comprises the above-described two-component room temperature curable epoxy resin composition.
Although it does not specifically limit as a field | area where the metal adhesive composition of this invention is used, The civil engineering / architecture field | area, the electric / electronic material field | area, etc. are mentioned.
The metal adhesive composition of the present invention is not limited to the adhesion between metal materials, but also has excellent adhesion to materials other than metals, and therefore can be used for adhesion between metal materials and other materials. .

Although it does not specifically limit as a metal of a to-be-adhered body, Specifically, aluminum, iron (steel), stainless steel, titanium, copper, nickel, chromium, gold | metal | money, various alloys etc. are mentioned, for example.
Although it does not specifically limit as adherend materials other than a metal, Specifically, a plastic, rubber | gum, mortar, concrete, ceramic, a tile etc. are mentioned, for example.

  The metal adhesive composition of the present invention is used by being applied to an adhesion site of an adherend by, for example, a trowel, a brush, a dispenser, an applicator, a spray, a roll coat or the like. However, the coating method is not limited to these.

  Since the metal adhesive composition of the present invention is curable at room temperature, it is possible to reduce the residual stress generated in the joint, and it is not necessary to remove distortion necessary for welding or putty work before painting. Therefore, workability can be improved. In addition, the metal adhesive composition of the present invention exhibits excellent adhesiveness at room temperature and can maintain adhesiveness even at high temperatures. Furthermore, when it contains a core-shell type powdery polymer, it has excellent toughness in addition to the above characteristics.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to these.
(Examples 1 to 25 and Comparative Examples 1 to 3)
The components shown in Table 1 below were mixed and dispersed with the composition (parts by mass) shown in Table 1 using a stirrer to obtain the room temperature curable epoxy resin compositions shown in Table 1.
About the obtained composition, adhesiveness was evaluated by the following method.
The results are shown in Table 1.

<Adhesion test>
After preparing two 150 × 25 × 2 mm steel plates and laminating these end portions 5 mm through the obtained compositions, the test specimens were left at 23 ° C. and 60% RH for 1 week. Obtained.
Using the obtained specimen, tensile shear bond strength (initial) was measured at room temperature (23 ° C.) in accordance with JIS K6850-1999.
Further, the obtained test specimen was allowed to stand at 120 ° C. for 30 minutes and then cooled to room temperature, and the tensile shear adhesive strength (high temperature resistance) was measured in the same manner.

The components in Table 1 are as follows.
-Bifunctional epoxy resin 1: Bisphenol A type epoxy resin, YD128, manufactured by Toto Kasei Co., Ltd.-Bifunctional epoxy resin 2: Bisphenol F type epoxy resin, Epicoat 807, manufactured by Japan Epoxy Resins Co., Ltd.-Trifunctional epoxy resin: Glycidylamine type epoxy resin, Epicoat 630, manufactured by Japan Epoxy Resin Co., Ltd. ・ Core shell type powdered polymer: ZEON F351, manufactured by Nippon Zeon Co., Ltd. ・ Amine compound 1: diethylenetriamine, manufactured by Kanto Chemical Co., Ltd. ・ Amine compound 2 : Triethylenetetramine, manufactured by Kanto Chemical Co., Ltd. Amine compound 3: Tetraethylenepentamine, manufactured by Kanto Chemical Co., Ltd. Amine compound 4: Metaxylenediamine, MXDA, manufactured by Mitsubishi Gas Chemical Co., Ltd. Amine compound 5: Mannich modified xylylenediamine, Daitokuller X9442, Daito Sangyo Co., Ltd., amine compound 6: isophorone diamine, manufactured by Kanto Chemical Co., Ltd.

Dicyandiamide: manufactured by Kanto Chemical Co., Ltd. Imidazole compound 1: 1-cyanoethyl-2-phenylimidazole, Curazole 2PZ-CN, manufactured by Shikoku Kasei Co., Ltd. Imidazole compound 2: 1-cyanoethyl-2-methylimidazole, Curazole 2MZ -CN, manufactured by Shikoku Kasei Co., Ltd.-Imidazole compound 3: 1,2-dimethylimidazole, 1,2DMZ, manufactured by Shikoku Kasei Co., Ltd.-Imidazole compound 4: 1-benzyl-2-methylimidazole, 1B2MZ, Shikoku Chemical (・ Imidazole compound 5: 1-isobutyl-2-methylimidazole, 1I2MZ, manufactured by Shikoku Kasei Co., Ltd. ・ Imidazole compound 6: 1-benzyl-2-phenylimidazole, 1B2PZ, manufactured by Shikoku Kasei Co., Ltd. ・ Imidazole compound 7: 2-ethyl-4-methylimi Dodazole, 2E4MZ, manufactured by Shikoku Kasei Co., Ltd. ・ Imidazole compound 8: 2-undecylimidazole, CIIZ, manufactured by Shikoku Kasei Co., Ltd. ・ Imidazole compound 9: 2-methylimidazole, Cureazole 2MZ, manufactured by Shikoku Kasei

As is apparent from the results shown in Table 1, the dicyandiamide-free composition (Comparative Example 1), the imidazole compound-free composition (Comparative Example 2), and the dicyandiamide- and imidazole compound-free composition (Comparative) In all of Examples 3), the initial tensile shear bond strength was low. Further, the tensile shear adhesive strength (high temperature resistance) was 150 to 170 kgf / cm ² , which was higher than the initial value. This is considered to be due to the progress of curing of the composition by being placed at a high temperature.
On the other hand, compositions (Examples 1 to 25) using dicyandiamide and an imidazole compound in combination have a tensile shear adhesive strength (initial) of 184 to 210 kgf / cm ² and a tensile shear adhesive strength (high temperature resistance) of 180 to 201 kgf / cm ² . That is, it exhibited extremely excellent adhesiveness at room temperature and maintained adhesiveness even at high temperatures. In particular, the initial adhesiveness was about twice as large as that of the compositions of Comparative Examples 1 to 3. That is, none of the conventional room temperature curable epoxy resin compositions had a tensile shear bond strength (initial) of 200 kgf / cm ² to metal, but the present invention has a tensile shear bond strength (initial) of 200 kgf / cm ² . It was an epoch-making thing in the point which can provide the two-pack type room temperature curing epoxy resin composition which exceeds. In addition, in the conventional room temperature curable epoxy resin composition, the initial and high temperature resistance tensile shear adhesive strength did not exceed 180 kgf / cm ² , but the present invention has adhesiveness even when left at high temperature. The tensile shear bond strength at the initial stage and high temperature resistance was 180 kgf / cm ² or more.

Claims (4)

A main agent comprising a bifunctional epoxy resin and a trifunctional epoxy resin, containing 30% by mass or more of the trifunctional epoxy resin, and containing an epoxy resin that is liquid at room temperature;
A two-pack room temperature curable epoxy resin composition comprising a curing agent containing an aliphatic amine compound and / or an alicyclic amine compound, dicyandiamide, and an imidazole compound. The content of the amine compound is such that the active hydrogen of the amine compound is 0.6 to 1.0 equivalent with respect to the epoxy group of the epoxy resin,
The dicyandiamide content is 0.1 to 2.0 parts by mass with respect to 100 parts by mass of the epoxy resin,
The two-component room temperature curable epoxy resin composition according to claim 1, wherein the content of the imidazole compound is 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the epoxy resin.   The main agent and / or the curing agent further comprises a core made of a (meth) acrylate polymer having a glass transition temperature of −30 ° C. or lower and a (meth) acrylate polymer having a glass transition temperature of 70 ° C. or higher. The two-pack type room temperature curable epoxy resin composition according to claim 1 or 2, comprising a core-shell type powdery polymer composed of a shell.   A metal adhesive composition comprising the two-pack type room temperature curable epoxy resin composition according to claim 1.