JP6063304B2 - Microcapsule type curing agent for epoxy resin - Google Patents

Description

  The present invention relates to a microcapsule type curing agent for epoxy resin, a curable epoxy resin composition containing the same, and a cured product thereof.

Epoxy resin has excellent performance in terms of mechanical properties, electrical properties, thermal properties, chemical resistance, adhesiveness, etc., and it can be used for paints, insulating materials for electrical and electronic materials, adhesives, etc. It is used for a wide range of applications. The epoxy resin composition generally used at present is a so-called two-component type in which two components of an epoxy resin and a curing agent are mixed at the time of use.
The two-part epoxy resin composition can be cured at room temperature, but the epoxy resin and the curing agent must be stored separately, and must be used after metering and mixing as required. It is complicated. In addition, since the usable time is limited, it is not possible to mix in large quantities in advance, and it is necessary to perform mixing work each time it is used. For this reason, the frequency of work increases, and a reduction in work efficiency is inevitable.
In order to solve the problem of such a two-part epoxy resin composition, several one-part epoxy resin compositions have been proposed so far. As a one-part epoxy resin composition, for example, Patent Document 1 discloses a microcapsule type curing agent obtained by reacting the surface of a powdered amine compound with isocyanate to inactivate the surface of the amine compound. Yes.

JP 2009-203453 A

When impregnating an epoxy resin composition into a film-shaped molded article or substrate using a one-part epoxy resin composition using a microcapsule type curing agent, it is common to include a process of mixing using an organic solvent. is there. In such a production process, a microcapsule type curing agent having high solvent resistance even when dispersed in an organic solvent is required.
However, the microcapsule type curing agent described in Patent Document 1 has insufficient solvent resistance when mixed with an organic solvent, and a microcapsule type curing agent having further excellent solvent resistance is required.
In view of the above circumstances, an object of the present invention is to provide a microcapsule type curing agent having high solvent resistance even when dispersed in an organic solvent and an epoxy resin composition containing the same.

As a result of intensive studies to achieve the above object, the present inventor has a high solvent resistance even when dispersed in an organic solvent by using a microcapsule-type curing agent having a specific shell structure. As a result, the present invention was completed.
That is, the present invention is as follows.
[1]
A microcapsule type curing agent for epoxy resin having a core containing a curing agent and a shell covering the core, wherein the shell has an isocyanuric group and has an infrared wave number of 1630 to 1680 cm ⁻¹ . absorbing binding groups x, binding group y which absorbs infrared wave number 1680~1725cm ^-1, has a binding group z which absorbs infrared wave number 1730~1755cm ^-1, the binding groups x in the shell, y, And the concentration of z and Cx, Cy, and Cz, respectively, Cy / (Cx + Cy + Cz) is 0.4 or more and less than 1, a microcapsule type curing agent for epoxy resin.
[2]
The microcapsule type curing agent for epoxy resin according to [1], wherein the Cy / (Cx + Cy + Cz) is 0.4 or more and 0.62 or less.
[3]
The core is at least one selected from the group consisting of metal alkoxides, quaternary ammonium salts, tertiary alkyl phosphines, sulfinic acid compounds, and compounds having a structure represented by the following general formula (1) in the molecule. The microcapsule type curing agent for epoxy resin according to [1] or [2], which contains a seed compound.
(1)
(Wherein R ¹ , R ² , R ³ , and R ⁴ are each independently a hydrogen atom, a halogen group, an alkyl group having 1 to 20 carbon atoms that may contain a substituent, or an aromatic group that may contain a substituent. Group, an alkoxy group having 1 to 20 carbon atoms which may contain a substituent, or a phenoxy group which may contain a substituent.)
[4]
The core is at least one selected from the group consisting of metal alkoxides, quaternary ammonium salts, tertiary alkyl phosphines, sulfinic acid compounds, and compounds having a structure represented by the general formula (1) in the molecule. The microcapsule type curing agent for epoxy resin according to [3], which contains 0.1% by mass to 50% by mass of a seed compound.
[5]
The core is an amine curing agent, acid anhydride curing agent, phenol curing agent, mercaptan curing agent, boron halide curing agent, quaternary ammonium salt curing agent, urea curing agent and phosphine curing agent. The microcapsule type curing agent for epoxy resin according to any one of [1] to [4], comprising at least one curing agent selected from the group consisting of:
[6]
The microcapsule type curing agent for epoxy resin according to [5], wherein the core contains 50% by mass or more of an amine curing agent.
[7]
The microcapsule type curing agent for epoxy resin according to [6], wherein the amine curing agent is an imidazole compound or an imidazoline compound.
[8]
The curable epoxy resin composition containing the microcapsule type hardening | curing agent for epoxy resins of any one of [1]-[7], and an epoxy resin.
[9]
Hardened | cured material obtained by hardening the composition as described in [8].

  According to the present invention, it is possible to provide a microcapsule type curing agent and a curable epoxy resin composition having high solvent resistance when dispersed in an organic solvent.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as the present embodiment) will be described in detail.
In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

[Microcapsule type curing agent]
The microcapsule type curing agent of the present embodiment is a so-called core-shell type curing agent containing a core containing a curing agent and a shell covering the core. By being a core-shell type, it has latent curability.

(shell)
Shell according to the present embodiment includes an isocyanuric group, and linking group x that absorbs infrared wave number 1630～1680Cm ^-1, bonding group absorbs infrared wave number 1680~1725cm ^-1 y, wavenumber 1730～1755Cm ^{- 1} having a bonding group z that absorbs infrared rays.
In the curing agent of the present embodiment, the shell has an isocyanuric group, whereby the crosslink density of the shell is improved, and as a result, the solvent resistance is improved. In addition, the shell having the bonding group x is advantageous for obtaining a microcapsule-type curing agent having high resistance to mechanical shearing force, and the shell has the bonding group y to provide mechanical shearing. It is advantageous to obtain a microcapsule type curing agent having a high resistance against an organic solvent and a microcapsule type having a high resistance against a mechanical shearing force because the shell has the bonding group z. It is advantageous to obtain a curing agent.
Having the bonding groups x, y, and z in the shell can be measured using microscopic FT-IR.
The binding group x is not particularly limited, and examples thereof include a urea group.
The linking group y is not particularly limited, and examples thereof include a burette group and an isocyanuric group, and an isocyanuric group is preferable because the heat resistance of the cured product tends to increase.
The bonding group z is not particularly limited, and examples thereof include a urethane group.

  In the curing agent of the present embodiment, when the concentration of the bonding groups x, y, and z in the shell is Cx, Cy, and Cz, respectively, the ratio of the concentration of the bonding group y, that is, Cy / (Cx + Cy + Cz. ) Is 0.4 or more and less than 1. Thereby, the curing agent of the present embodiment is excellent in solvent resistance against an organic solvent. Cy / (Cx + Cy + Cz) is more preferably 0.4 or more and 0.62 or less because both solvent resistance and curing characteristics tend to be compatible.

The Cx, Cy, and Cz can be obtained by creating a calibration curve using a standard substance and a model compound as shown below.
(How to create a calibration curve)
Using terephthalonitrile as a standard substance, each of the following model compounds (A), (B), and (C) is precisely weighed and mixed at an arbitrary ratio, and then pulverized with KBr powder. To measure the infrared absorption spectrum. The area of the absorption band of 2240～2260Cm ^-1 nitrile group resulting from terephthalonitrile of standards in the obtained spectrum, the model compound absorption band of 1630～1680Cm ^-1 urea groups (A), the model The area ratio of the absorption band of 1680 to 1725 cm ⁻¹ of the isocyanuric group of the compound (B) and the absorption band of 1730 to 1755 cm ⁻¹ of the urethane group of the model compound (C) are obtained, respectively, and the relationship between the area ratio and the mass ratio is obtained. Create a calibration curve.
Model compound (A)
Model compound (B)
Model compound (C)
Standard substance: terephthalonitrile At the time of preparing the calibration curve, terephthalonitrile, model compound (A), model compound (B), and model compound (C), which are standard substances, may be commercial products. A product produced by a known method may be used.

(Measurement method of bonding group concentration)
By washing the microcapsule type curing agent with methanol and filtering, components other than the shell are removed to isolate the shell. After completely removing methanol at a temperature of 50 ° C. or less and drying, add 3 mg of terephthalonitrile, a standard substance, to 1 g of this shell, pulverize and mix in an agate mortar, and pulverize the resulting mixture with KBr powder. Then, an infrared absorption spectrum is measured using a tablet molding machine. By using the obtained spectrum chart and the calibration curve created by the above method, the concentrations of the bonding groups x, y, and z in the sample can be obtained.

In the present embodiment, the linking groups x, y, and z are derived from the chemical structure of the compound used in preparing the microcapsule type curing agent and / or the chemical structure generated by the reaction of the compound. Examples of such a compound include an isocyanate compound (s1) and a compound having a functional group that reacts with the isocyanate compound (s1).
Although it does not specifically limit as said isocyanate compound (s1), For example, aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, aliphatic triisocyanate, polyisocyanate is mentioned.
Although it does not specifically limit as said aliphatic diisocyanate, For example, ethylene diisocyanate, propylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate etc. can be mentioned.
The alicyclic diisocyanate is not particularly limited, and examples thereof include isophorone diisocyanate, 4-4′-dicyclohexylmethane diisocyanate, norbornane diisocyanate, 1,4-isocyanatocyclohexane, 1,3-bis (isocyanatomethyl) -cyclohexane. 1,3-bis (2-isocyanatopropyl-2-yl) -cyclohexane and the like.
The aromatic diisocyanate is not particularly limited, and examples thereof include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, xylene diisocyanate, and 1,5-naphthalene diisocyanate.
Examples of the aliphatic triisocyanate include 1,3,6-triisocyanatomethylhexane, 2,6-diisocyanatohexanoic acid-2-isocyanatoethyl, and the like.
The polyisocyanate is not particularly limited, and examples thereof include polymethylene polyphenyl polyisocyanate and polyisocyanate derived from the diisocyanate compound. Examples of the polyisocyanate derived from the diisocyanate include isocyanurate type polyisocyanate, burette type polyisocyanate, urethane type polyisocyanate, allophanate type polyisocyanate, and carbodiimide type polyisocyanate.

Examples of the compound having a functional group that reacts with the isocyanate compound (s1) include a compound (b1) having active hydrogen, an epoxy resin (e1), and the isocyanate compound (s1) itself.
Examples of the compound (b1) having an active hydrogen group include compounds having one or more active hydrogen groups in one molecule. A compound having two or more active hydrogen groups in one molecule is preferable from the viewpoint that the surface coating of the core can be suitably grown and a microcapsule-type curing agent having excellent storage stability can be produced.
Examples of the compound (b1) having an active hydrogen group include alcohols, primary amine compounds, secondary amine compounds, thiol compounds, and water. As the compound (b1) having an active hydrogen group, one type may be used alone, or two or more types may be used in combination.
It does not specifically limit as an epoxy resin (e1), For example, what is mentioned in the example of the epoxy resin (e2) used for the below-mentioned cores can be used.

In the present embodiment, a method for setting Cy / (Cx + Cy + Cz) to be 0.4 or more and less than 1 is not particularly limited. For example, a compound that functions as a catalyst when the core and the isocyanate group are trimerized. After reacting the isocyanate compound (s1) in the presence of (trimerization reaction accelerator) and reacting with a desired amount of isocyanate group, the compound (b1) having a compound having an active hydrogen group is added to further remain. This can be achieved by a method such as reacting an isocyanate group.
In the present embodiment, the compound (b1) having a compound having an active hydrogen group is preferably added after reacting the isocyanate compound (s1) in a desired amount in the presence of a trimerization reaction accelerator. In such a case, since the isocyanate compound (s1) undergoes a trimerization reaction to improve the reaction selectivity to become an isocyanuric group, it is easy to set Cy / (Cx + Cy + Cz) to 0.4 or more.

  In the present embodiment, the shell may contain a linking group other than the linking groups x, y, and z. Such other linking group is not particularly limited, but prevents hydrolysis reaction in a high humidity state, cures the storage stability and moisture resistance of the curing agent for epoxy resin, and cures the epoxy resin composition containing the same. From the viewpoint of improving the physical properties of the cured product obtained in this manner, it is more preferable that the shell does not have an ester group.

(core)
In the present embodiment, the curing agent contained in the core is not particularly limited, but from the viewpoint of curability of the epoxy resin composition, an amine curing agent, an acid anhydride curing agent, a phenol curing agent, a mercaptan curing. At least one or more from the group consisting of an agent, a boron halide curing agent, a quaternary ammonium salt curing agent, a urea curing agent and a phosphine curing agent is preferred.
The acid anhydride curing agent is not particularly limited, and examples thereof include phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and methyl nadic acid.
Although it does not specifically limit as said phenol type hardening | curing agent, For example, a phenol novolak, a cresol novolak, a bisphenol A novolak, etc. are mentioned.
The mercaptan-based curing agent is not particularly limited, and examples thereof include propylene glycol-modified polymercaptan, thiogluconic acid ester of trimethylolpropane, and polysulfide resin.
Although it does not specifically limit as said boron halide type hardening | curing agent, For example, the ethylamine salt of trifluoroborane etc. are mentioned.
Although it does not specifically limit as said quaternary ammonium salt type hardening | curing agent, For example, the phenol salt of 1,8-diazabicyclo (5,4,0) -undec-7-ene etc. are mentioned.
The urea curing agent is not particularly limited, and examples thereof include 3-phenyl-1,1-dimethylurea.
Although it does not specifically limit as said phosphine type | system | group hardening | curing agent, For example, a triphenyl phosphine, tetraphenyl phosphonium tetraphenyl borate, etc. are mentioned.

In the present embodiment, the core preferably contains an amine curing agent because it tends to be excellent in low-temperature curability and storage stability.
In the present embodiment, the content of the amine curing agent in the core is not particularly limited, but is preferably 50% by mass or more. When the content of the amine curing agent in the core is 50% by mass or more, the curability of the one-component epoxy resin composition tends to be good. More preferably, it is 60 mass% or more, More preferably, it is 70 mass% or more.

  In the present embodiment, the amine-based curing agent is not particularly limited, but is an amine-based curing agent containing an amine compound (a1) and an amine adduct (A) described later from the viewpoint of having an appropriate reactivity. It is particularly preferred.

The amine compound (a1) is not particularly limited, and for example, a compound having at least one primary amino group and / or secondary amino group but having no tertiary amino group; at least one tertiary amino group; Examples thereof include compounds having at least one active hydrogen group.
The compound having at least one primary amino group but not having a tertiary amino group is not particularly limited, and examples thereof include aliphatic primary amines, alicyclic primary amines, and aromatic primary amines. It is done. As aliphatic primary amines, for example, methylamine, ethylamine, propylamine, butylamine, ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, ethanolamine, propanolamine, etc. Examples of aromatic primary amines such as cyclohexylamine and isophoronediamine include aniline, toluidine, diaminodiphenylmethane, and diaminodiphenylsulfone.
Although it does not specifically limit as a compound which has an at least 1 sort (s) of secondary amino group, but does not have a tertiary amino group, For example, any of aliphatic secondary amine, alicyclic secondary amine, and aromatic secondary amine May be used. Examples of aliphatic secondary amines include dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, dimethanolamine, diethanolamine, and dipropanolamine. Alicyclic secondary amines include dicyclohexylamine. Examples of aromatic secondary amines such as piperidine and piperidone include diphenylamine, phenylmethylamine, and phenylethylamine.
In the compound having at least one tertiary amino group and at least one active hydrogen group, the active hydrogen group is not particularly limited. For example, a primary amino group, a secondary amino group, a hydroxyl group, a thiol group, a carboxylic acid, A hydrazide group etc. are mentioned.
The compound having at least one tertiary amino group and at least one active hydrogen group is not particularly limited, and examples thereof include 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2. -Amino alcohols such as dimethylaminoethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, methyldiethanolamine, triethanolamine, N-β-hydroxyethylmorpholine; 2- (dimethylaminomethyl) phenol; Aminophenols such as 2,4,6-tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenyl Midazole, 1-aminoethyl-2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-ethyl-4-methyl Imidazoles such as imidazole, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4-methylimidazole; 1- (2 -Hydroxy-3-phenoxypropyl) -2-phenylimidazoline, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazoline, 2-methylimidazoline, 2,4-dimethylimidazoline, 2-ethylimidazoline, 2 -Ethyl-4-methylimidazoline, 2-benzylimidazoline, 2 -Phenylimidazoline, 2- (o-tolyl) -imidazoline, tetramethylene-bis-imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-imidazoline, 1,3,3-trimethyl-1, 4-tetramethylene-bis-imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-4-methylimidazoline, 1,3,3-trimethyl-1,4-tetramethylene-bis-4- Imidazolines such as methylimidazoline, 1,2-phenylene-bis-imidazoline, 1,3-phenylene-bis-imidazoline, 1,4-phenylene-bis-imidazoline, 1,4-phenylene-bis-4-methylimidazoline; Dimethylaminopropylamine, diethylaminopropylamine, dipropylaminopropylamine, Tertiary aminoamines such as butylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, N-methylpiperazine, N-aminoethylpiperazine, diethylaminoethylpiperazine; 2-dimethylaminoethanethiol; Amino mercaptans such as 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptopyridine, 4-mercaptopyridine; N, N-dimethylaminobenzoic acid, N, N-dimethylglycine, nicotinic acid, isonicotinic acid, Examples include aminocarboxylic acids such as picolinic acid; aminohydrazides such as N, N-dimethylglycine hydrazide, nicotinic acid hydrazide, and isonicotinic acid hydrazide.
In the present embodiment, from the viewpoint of curing speed, as the compound having at least one tertiary amino group and at least one active hydrogen group, imidazoles and imidazolines are preferable, and 2-methylimidazole, 2-ethyl- 4-methylimidazole is more preferred.

Although it does not specifically limit as said amine adduct (A), For example, the compound chosen from the group which consists of a carboxylic acid compound, a sulfonic acid compound, a urea compound, an isocyanate compound (s2), an epoxy resin (e2), and an amine compound ( Examples thereof include compounds having an amino group obtained by reaction with a2).
The carboxylic acid compound is not particularly limited, and examples thereof include succinic acid, adipic acid, sebacic acid, phthalic acid, and dimer acid.
Although it does not specifically limit as said sulfonic acid compound, For example, ethanesulfonic acid, p-toluenesulfonic acid etc. are mentioned.
Although it does not specifically limit as said urea compound, For example, urea, methyl urea, dimethyl urea, ethyl urea, t-butyl urea etc. are mentioned.
The isocyanate compound (s2) is not particularly limited, and examples thereof include aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, aliphatic triisocyanates, and polyisocyanates. Specifically, the isocyanate compounds (s1 ) Are listed.
Although it does not specifically limit as said epoxy resin (e2), Either a mono epoxy compound, a polyhydric epoxy compound, those mixtures, etc. are mentioned.
The monoepoxy compound is not particularly limited. For example, butyl glycidyl ether, hexyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether, p-tert-butylphenyl glycidyl ether, ethylene oxide, propylene oxide, styrene oxide, paraxylyl. Examples include glycidyl ether, glycidyl acetate, glycidyl butyrate, glycidyl hexoate, and glycidyl benzoate.
The polyvalent epoxy compound is not particularly limited. For example, bisphenol A, bisphenol F, bisphenol AD, bisphenol S, tetramethyl bisphenol A, tetramethyl bisphenol F, tetramethyl bisphenol AD, tetramethyl bisphenol S, tetrabromobisphenol. A, bisphenol type epoxy resin obtained by glycidylation of bisphenols such as tetrachlorobisphenol A and tetrafluorobisphenol A; other dihydric phenols such as biphenol, dihydroxynaphthalene and 9,9-bis (4-hydroxyphenyl) fluorene Glycidylated epoxy resin; 1,1,1-tris (4-hydroxyphenyl) methane, 4,4- (1- (4- (1- (4-hydroxyphenyl)) -1-Methylethyl) phenyl) ethylidene) epoxy resin glycidylated trisphenols such as bisphenol; epoxy glycidylated tetrakisphenols such as 1,1,2,2, -tetrakis (4-hydroxyphenyl) ethane Resin; Epoxy resin obtained by glycidylation of polyhydric phenols such as novolac-type epoxy resin obtained by glycidylation of novolak such as phenol novolak, cresol novolak, bisphenol A novolak, brominated phenol novolak, brominated bisphenol A novolak; Aliphatic ether type epoxy resin obtained by glycidylation of polyhydric alcohol such as glycol; ether ester obtained by glycidylation of hydroxycarboxylic acid such as p-oxybenzoic acid and β-oxynaphthoic acid Type epoxy resin; ester type epoxy resin obtained by glycidylation of polycarboxylic acid such as phthalic acid and terephthalic acid; glycidylated compound of amine compound such as 4,4-diaminodiphenylmethane and m-aminophenol, and amine such as triglycidyl isocyanurate Type epoxy resin; and alicyclic epoxides such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate.
In the present embodiment, the epoxy resin (e2) is preferably a polyvalent epoxy compound because of the excellent adhesiveness and heat resistance of the resulting cured product, more preferably an epoxy resin obtained by glycidylating polyhydric phenols, More preferred are bisphenol-type epoxy resins, and glycidylated products of bisphenol A and glycidylated products of bisphenol F are even more preferable.
Although it does not specifically limit as said amine compound (a2), For example, what was enumerated by the amine compound (a1) mentioned above etc. are mentioned.
Among these amine adducts (A), those obtained by reaction of the epoxy resin (e2) and the amine compound (a2) are particularly preferable. The amine adduct (A) obtained by the reaction between the epoxy resin (e2) and the amine compound (a2) is also preferable from the viewpoint that the unreacted amine compound (a2) can be used as the amine compound (a1).

It is preferable that the hardening | curing agent of this Embodiment contains the compound (b2) in which a core has an active hydrogen group. In such a case, the solvent resistance tends to be further improved by chemically bonding the shell and the core surface.
Examples of the compound (b2) having an active hydrogen group include a compound having at least one functional group selected from the group consisting of a hydroxyl group, a primary amino group, a secondary amino group, a carboxyl group, an amide group, and an active methylene group. More preferably, it is contained in the curing agent that is the main component of the core. In the present embodiment, the amine compound (a1) can also be used as the compound (b2) having an active hydrogen group.

In the present embodiment, the core is not particularly limited, but for example, from the viewpoint of further improving the solvent resistance to organic solvents, metal alkoxides, quaternary ammonium salts, tertiary alkyl phosphines, sulfinic acid compounds, and It may contain at least one compound selected from the group consisting of compounds having a structure represented by the following general formula (1) in the molecule (hereinafter sometimes referred to as “compounds such as metal alkoxides”). preferable.
(1)
{Wherein R ¹ , R ² , R ³ , and R ⁴ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms that may contain a substituent, or an aromatic group that may contain a substituent. It is a C1-C20 alkoxy group which may contain a group group, a substituent, or an aryloxy group which may contain a substituent. }
When the core contains a compound such as the metal alkoxides, the reason why the solvent resistance to the organic solvent is further improved is not certain, but when the microcapsule-type curing agent is produced, the compound forms a shell. It functions as a catalyst when the isocyanate group undergoes a trimerization reaction, and the amount of isocyanuric group formed increases, and as a result, the ratio of the linking group concentration in the shell, that is, Cy / (Cx + Cy + Cz) takes a value of 0.4 or more. This is thought to be easier.
For the above reasons, it is preferable that the core contains a compound (trimerization reaction accelerator) that functions as a catalyst when the isocyanate group undergoes a trimerization reaction, in addition to the compounds such as the metal alkoxides.

  The metal alkoxides are not particularly limited, and examples thereof include sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, potassium t-butoxide and the like.

  The quaternary ammonium salts are not particularly limited, and examples thereof include tetramethylammonium hydroxide, trimethyl-2-hydroxyethylammonium hydroxide, and tetramethylammonium capryate.

  The tertiary alkyl phosphines are not particularly limited, and examples thereof include triethylphosphine, tri-n-propylphosphine, tri-isopropylphosphine, tri-n-butylphosphine, tri-iso-butylphosphine, and tri-sec-butyl. Examples include phosphine, tri-tert-butylphosphine, tri-n-pentylphosphine, and tri-cyclohexylphosphine.

  The sulfinic acid compounds are not particularly limited, and examples thereof include sodium p-toluenesulfinate.

(1)
In the compound having a structure represented by the general formula (1) in the molecule, each of R ¹ , R ² , R ³ , and R ⁴ independently contains a hydrogen atom, a halogen atom, or a substituent. Or an alkyl group having 1 to 20 carbon atoms, an aromatic group which may contain a substituent, an alkoxy group having 1 to 20 carbon atoms which may contain a substituent, or an aryloxy group which may contain a substituent.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
The alkyl group having 1 to 20 carbon atoms is a linear or branched saturated hydrocarbon group, and may have a structure including a cyclic saturated hydrocarbon group such as an alicyclic group. Furthermore, these alkyl groups may contain a substituent within a range not affecting the reaction. Examples of these substituents include an aromatic group, a halogen atom, a hydroxyl group, and a nitrile group. .
The aromatic group is a functional group having a conjugated cyclic structure, and examples thereof include a phenyl group, a naphthyl group, an anthracenyl group, and a biphenyl group. Further, these aromatic groups may contain a substituent within a range not affecting the reaction. Examples of these substituents include an alkyl group, a halogen atom, a nitrile group, and an alkoxy group. It is done.
The said C1-C20 alkoxy group means the oxy group which the said C1-C20 alkyl group couple | bonded, and a linear structure or a branched structure may be sufficient as it. Furthermore, these alkoxy groups may contain a substituent within a range that does not affect the reaction. Examples of these substituents include aromatic groups, halogen atoms, hydroxyl groups, and nitrile groups. It is done.
The aryloxy group may contain a substituent within a range that does not affect the reaction. Examples of these substituents include an alkyl group, a halogen atom, a nitrile group, and an alkoxy group.
The compound having the structure represented by the general formula (1) in the molecule is not particularly limited. For example, in the following description, as an example of a compound having at least one tertiary amino group and at least one active hydrogen group The reaction product of the imidazole mentioned and the said epoxy resin (e2) can be mentioned.
In the present embodiment, the compound having the structure represented by the general formula (1) in the molecule is a reaction product of 2-methylimidazole and a monoepoxy compound, and the diffusibility of the curing agent is good. This is preferable.

  In this Embodiment, it is preferable that a core contains 0.1 mass% or more and 50 mass% or less of compounds, such as said metal alkoxide. By containing 0.1% by mass or more, the ratio of the bonding group concentration, that is, Cy / (Cx + Cy + Cz) tends to take a value of 0.4 or more, and the solvent resistance with respect to the organic solvent tends to be further improved. More preferably, the content is 10% by mass or more. On the other hand, the content is 50% by mass or less, whereby the curability is improved. More preferably, it is 40 mass% or less, More preferably, it is 35 mass% or less.

  In the present embodiment, the core is not particularly limited, but from the viewpoint of storage stability of the epoxy resin composition, the core is preferably in a powder form. The average particle size of the core is preferably from 0.1 to 50 μm, more preferably from 0.5 to 10 μm, still more preferably from 0.5 to 5 μm. When the average particle size is 0.1 μm or more, the low temperature curability and the storage stability are excellent. By setting the average particle size in the range of 0.1 to 50 μm, a homogeneous cured product can be obtained. In the present specification, “average particle diameter” refers to the median diameter. The average particle diameter can be measured with a laser diffraction particle size distribution measuring apparatus.

  In the present embodiment, the shape of the core is not particularly limited, and may be either spherical or indeterminate, and spherical is preferable for reducing the viscosity of the one-component epoxy resin composition. Here, “spherical” includes not only true spheres but also shapes with rounded irregular corners.

[Production method of microcapsule type curing agent]
Hereinafter, a method for producing a microcapsule type curing agent by encapsulating a core with a shell will be described.
The method for producing the microcapsule type curing agent of the present embodiment is not particularly limited. For example, (i) a capsule forming step of forming a shell covering the core, and a solvent removing step of removing the dispersion medium after the capsule is formed A method of producing a microcapsule-type curing agent by a process including a process, (ii) a method of producing a core-shell type curing agent in an epoxy resin (e3), and producing a microcapsule-type curing agent as a masterbatch type, etc. Is mentioned.

First, the method (i) will be described.
In the capsule forming step, the core, the isocyanate compound (s1), and the compound having a functional group that reacts with the isocyanate compound (s1) are reacted to form a capsule covering the core as a reaction product.
The method for producing the core is not particularly limited. For example, when the core contains an amine-based curing agent or the like, it was obtained after the amine adduct (A) was produced from the amine compound (a2) and the epoxy resin (e2). A method of dissolving an amine adduct (A) and, if necessary, a compound such as a metal alkoxide in a solvent, removing the solvent, drying, and pulverizing to form amine adduct particles (corresponding to the core) Etc.

  The capsule forming reaction is not particularly limited, but is preferably performed in a reaction solution in which the core is dispersed in a dispersion medium. The capsule forming reaction is not particularly limited, but is preferably performed at a temperature below the melting point or softening point of the amine adduct contained in the core, and more preferably at a temperature below the melting point or softening point of the core.

The dispersion medium used in the capsule forming reaction is not particularly limited, but preferably has a boiling point of 150 ° C. or less at 1 atm from the viewpoint of easy removal of the dispersion medium from the reaction solution. What is 120 degreeC is more preferable. The viscosity of the dispersion medium is not particularly limited, but is preferably 1000 mPa · s or less at 25 ° C., more preferably 0.2 to 10 mPa · s. When the viscosity of the dispersion medium is 1000 mPa · s or less, the viscosity at the time of encapsulation is appropriate and it is easy to react uniformly. Further, the dispersion medium is preferably a dispersion medium having a boiling point of 150 ° C. or less at 1 atm and a viscosity of 1000 mPa · s or less at 25 ° C.
The type of the dispersion medium is not particularly limited as long as the core does not dissolve. For example, cyclohexane (boiling point 80.7 ° C., viscosity 0.898 mPa · s: 25 ° C.) and hexane (boiling point 69 ° C., viscosity 0.299 mPa · s). : 25 ° C.).

The number of times of the encapsulation processing is not particularly limited, and may be performed twice or more if necessary. In this case, the reaction product once collected may be dispersed once again in the dispersion medium and then reacted with the isocyanate compound. The number of times of encapsulation is preferably 5 times or less, and more preferably 3 times or less from the viewpoint of suppressing the manufacturing cost.
In the dispersion medium after the capsule forming step, an unreacted isocyanate compound (s1), a compound having a functional group that reacts with the isocyanate compound (s1), or the like may remain. Since these residues remain, storage stability is lowered, and therefore it is preferable to remove the dispersion medium after the capsule forming step.

  The method for removing the dispersion medium is not particularly limited, but it is possible to remove the unreacted isocyanate compound (s1) together with the dispersion medium and the residue such as the compound having a functional group that reacts with the isocyanate compound (s1) together with the dispersion medium. preferable. An example of such a method is a method of removing the dispersion medium by filtration.

Moreover, it is preferable to wash the microcapsule type curing agent after removing the dispersion medium. By washing the microcapsule type curing agent, unreacted compounds adhering to the surface of the microcapsule type curing agent can be removed. The washing method is not particularly limited, but the residue obtained by filtration can be washed using a solvent that does not dissolve the dispersion medium or the microcapsule type curing agent.
It is preferable to dry the microcapsule type curing agent after filtration or washing from the viewpoint of obtaining a powdery microcapsule type curing agent. The drying method is not particularly limited, but it is preferable to dry at a temperature below the melting point or softening point of the core, for example, drying under reduced pressure. The pulverization of the microcapsule type curing agent is preferable from the viewpoint of facilitating the blending of a wide variety of one-component epoxy resin compositions.

Next, the method (ii) will be described.
As a method for producing a microcapsule type curing agent for epoxy resin as a master batch type, for example, there is a production method in which a core-shell type curing agent is produced in an epoxy resin (e3).
It does not specifically limit as said epoxy resin (e3), The thing similar to the said epoxy resin (e1) is mentioned.

When producing a microcapsule type curing agent as a master batch type, a curing agent (h) other than the core can be used in combination. The curing agent (h) is not particularly limited, and examples thereof include at least one selected from the group consisting of acid anhydrides, phenols, hydrazines, and guanidines, and two or more types may be used in combination. it can.
The acid anhydrides are not particularly limited. For example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, -3-chlorophthalic anhydride, -4 anhydride -Chlorophthalic acid, benzophenone tetracarboxylic anhydride, succinic anhydride, methyl succinic anhydride, dimethyl succinic anhydride, dichlor succinic anhydride, methyl nadic acid, dodecyl succinic acid, chlorendec anhydride, maleic anhydride and the like.
The phenols are not particularly limited, and examples thereof include phenol novolak, cresol novolak, and bisphenol A novolak.
The hydrazines are not particularly limited, and succinic acid dihydrazide, adipic acid dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide terephthalic acid dihydrazide, p-oxybenzoic acid hydrazide, salicylic acid hydrazide, phenylaminopropionic acid hydrazide, maleic acid dihydrazide, etc. Is mentioned.
The guanidines are not particularly limited, and examples thereof include dicyandiamide, methylguanidine, ethylguanidine, propylguanidine, butylguanidine, dimethylguanidine, trimethylguanidine, phenylguanidine, diphenylguanidine, and toluylguanidine.
As the curing agent (h), guanidines and acid anhydrides are preferable, and dicyandiamide, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylnadic acid anhydride are more preferable. These curing agents are preferable from the viewpoint of providing a composition having excellent curability and storage stability and obtaining a cured product having excellent heat resistance and water resistance.

[Curable epoxy resin composition]
The curable epoxy resin composition of the present embodiment contains the microcapsule type curing agent and the epoxy resin.

  The epoxy resin is not particularly limited, and examples thereof include those listed with the epoxy resin (e2). The epoxy resin is preferably a polyvalent epoxy compound, more preferably a glycidylated epoxy resin, more preferably a bisphenol type epoxy resin, because the cured product obtained has excellent adhesion and heat resistance. More preferred are glycidylated products of bisphenol A or glycidylated products of bisphenol F.

In the curable epoxy resin composition of the present embodiment, the contents of the microcapsule-type curing agent and the epoxy resin can be determined from the viewpoints of curability and properties of the cured product, and are not particularly limited, but the microcapsules are based on mass. The mold curing agent: epoxy resin is preferably 0.1: 100 to 500: 100, more preferably 0.2: 100 to 200: 100.
A practically satisfactory curing performance can be obtained at 0.1: 100 or more, and a curing agent having a well-balanced curing performance can be obtained at 500: 100 or less without uneven distribution of the epoxy resin composition of the present invention. .

The curable epoxy resin composition of the present embodiment can be used as required by a filler, a reinforcing material, a filler, conductive fine particles, a pigment, an organic solvent, a reactive diluent, a non-reactive diluent, a resin, a crystalline alcohol. A coupling agent or the like may be contained.
Examples of the extender include, for example, polymer materials such as thermoplastic resins and cellulose, low molecular materials such as phthalate esters, and inorganic substances such as mica.

Examples of the reinforcing material include inorganic fibers such as carbon fiber, glass fiber, and asbestos fiber, and organic fibers such as aramid fiber, nylon, and polyester.
Examples of the filler include, for example, coal tar, glass fiber, asbestos fiber, boron fiber, carbon fiber, cellulose, polyethylene powder, polypropylene powder, quartz powder, mineral silicate, mica, asbestos powder, slate powder. , Kaolin, aluminum oxide trihydrate, aluminum hydroxide, chalk powder, gypsum, calcium carbonate, antimony trioxide, penton, silica, aerosol, lithopone, barite, titanium dioxide, carbon black, graphite, carbon nanotube, fullerene, oxidation Examples thereof include iron, gold, silver, aluminum powder, iron powder, nano-sized metal crystals, intermetallic compounds, and the like, all of which are effectively used depending on the application.
Examples of the conductive fine particles include resin particles whose surface is coated with metal particles such as gold and silver, and graphite particles.
Examples of the pigment include inorganic pigments such as titanium dioxide and organic pigments such as azo pigments.
Examples of the organic solvent include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate and the like.
Examples of the reactive diluent include, for example, butyl glycidyl ether, N, N′-glycidyl-o-toluidine, phenyl glycidyl ether, styrene oxide, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6- Examples include hexanediol diglycidyl ether.
Examples of the non-reactive diluent include dioctyl phthalate, dibutyl phthalate, dioctyl adipate, and petroleum solvents.
Examples of the resins include modified epoxy resins such as polyester resins, polyurethane resins, acrylic resins, polyether resins, melamine resins, urethane-modified epoxy resins, rubber-modified epoxy resins, and alkyd-modified epoxy resins.
Examples of the crystalline alcohol include 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, pentaerythritol, sorbitol, sucrose, and trimethylolpropane.

The cured product of the present embodiment can be produced by curing the curable epoxy resin composition.
The curing method is not particularly limited, and examples thereof include a method of heating at 25 ° C. to 350 ° C. for 1 second to 120 hours.

  The use of the curable epoxy resin composition of the present embodiment is not particularly limited. For example, in addition to the adhesive and / or the bonding paste and the bonding film, the conductive material, the anisotropic conductive material, the insulating material, the sealing material. It is useful as a stopping material, a coating material, a coating composition, a prepreg, a heat conductive material and the like.

Although the specific use as an adhesive agent and / or a bonding paste and a bonding film is not particularly limited, for example, it is useful as a liquid adhesive, a film adhesive, a die bonding material, or the like.
The method for producing the film adhesive is not particularly limited, and examples thereof include methods described in JP-A-62-141083 and JP-A-05-295329. More specifically, after producing a solution in which a solid epoxy resin, a liquid epoxy resin, and a solid urethane resin are dissolved, mixed, and dispersed in toluene so as to be 50% by mass, the curability of this embodiment is obtained. An epoxy resin composition is added to the solution in an amount of 30% by mass and dispersed to prepare a varnish. The obtained varnish is applied to, for example, a peeling polyethylene terephthalate substrate having a thickness of 50 μm so that the toluene has a thickness of 30 μm after drying. By drying toluene, it is possible to obtain a bonding film having latent curability that is inactive at room temperature but exhibits adhesiveness by heating.

Specific applications as the conductive material are not particularly limited, and examples thereof include a conductive film and a conductive paste. Examples of the anisotropic conductive material include an anisotropic conductive film and an anisotropic conductive paste. The production method is not particularly limited, and for example, there is a method described in JP-A-01-113480. More specifically, for example, in the production of the bonding film described above, the conductive material and the anisotropic conductive material are mixed and dispersed at the time of preparing the varnish, and are manufactured by applying to a substrate for peeling and then drying. can do.
The conductive particles are not particularly limited, and may be solder particles, nickel particles, nano-sized metal crystals, metal particles coated with other metals, metal particles such as copper and silver inclined particles, or styrene, for example. Resin, urethane resin, melamine resin, epoxy resin, acrylic resin, phenol resin, styrene-butadiene resin, etc. are coated with conductive thin films such as gold, nickel, silver, copper, solder, etc. The In general, the conductive particles are spherical fine particles of about 1 to 20 μm. The substrate for forming a film is not particularly limited, and for example, polyester, polyethylene, polyimide, polytetrafluoroethylene and the like can be used.

  Specific applications as the insulating material are not particularly limited, and examples thereof include an insulating adhesive film and an insulating adhesive paste. By using the bonding film, an insulating adhesive film that is an insulating material can be obtained. In addition to using a sealing material, an insulating adhesive paste can be obtained by blending an insulating filler among the fillers. As a sealing material, it is useful as a solid sealing material, a liquid sealing material, a film-like sealing material, etc., and as a liquid sealing material, it is useful as an underfill material, a potting material, a dam material, or the like. The method for producing the sealing material is not particularly limited. For example, in JP-A-5-43661 and JP-A-2002-226675, there is a description as a molding material for sealing / impregnating electric / electronic parts. . More specifically, bisphenol A type epoxy resin, as a curing agent, for example, methylhexahydrophthalic anhydride as an acid anhydride curing agent, and spherical fused silica powder are added and mixed uniformly, and then the curability of this embodiment is added. An epoxy resin composition can be added and mixed uniformly to obtain a sealing material.

  The specific application as the coating material is not particularly limited, and examples thereof include an electronic material coating material, an overcoat material for a printed wiring board cover, and a resin composition for interlayer insulation of a printed board. The method for producing the coating material is not particularly limited. For example, in JP-B-4-6116, JP-A-7-304931, JP-A-8-64960, and JP-A-2003-246838. There are various methods described. More specifically, silica or the like is selected from the fillers, and bisphenol A type epoxy resin, phenoxy resin, rubber-modified epoxy resin, etc. are blended as fillers, and the curable epoxy resin composition of the present embodiment is further blended. Combine and prepare 50% solution with methyl ethyl ketone. This is coated on a polyimide film with a thickness of 50 μm, and a copper foil is overlaid, laminated at 60 to 150 ° C., and the laminate is heated and cured at 180 to 200 ° C. to coat the interlayer with an epoxy resin composition. A laminated sheet can be obtained.

  The method for producing the coating composition is not particularly limited, and examples thereof include methods described in JP-A Nos. 11-323247 and 2005-113103. More specifically, titanium dioxide, talc, and the like are blended with a bisphenol A type epoxy resin, and a 1: 1 mixed solvent of methyl isobutyl ketone / xylene is added as a mixed solvent, stirred, and mixed to obtain a main agent. An epoxy coating composition can be obtained by adding and uniformly dispersing the curable epoxy resin composition of the present embodiment to this.

  The method for producing the prepreg is not particularly limited. For example, as in the methods described in JP-A-09-71633, WO98 / 44017, etc., an epoxy resin composition is impregnated into a reinforcing substrate and heated. Can be obtained. Examples of the varnish solvent to be impregnated include methyl ethyl ketone, acetone, ethyl cellosolve, methanol, ethanol, isopropyl alcohol, and the like. It is preferable that these solvents do not remain in the prepreg. In addition, although the kind of reinforcement base material is not specifically limited, For example, paper, a glass cloth, a glass nonwoven fabric, an aramid cloth, a liquid crystal polymer etc. are mentioned as an example. The ratio of the resin composition and the reinforcing substrate is not particularly limited, but it is usually preferable that the resin content in the prepreg is 20 to 80% by mass.

  The method for producing the heat conductive material is not particularly limited, and examples thereof include Japanese Patent Application Laid-Open Nos. 06-136244, 10-237410, and 2000-3987. More specifically, an epoxy resin as a thermosetting resin, a phenol novolac curing agent as a curing agent, and graphite powder as a heat conductive filler are blended and uniformly kneaded. A thermally conductive resin paste can be obtained by adding the curable epoxy resin composition of the present embodiment to this.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.

(Surface IR measurement and bond group concentration measurement)
(Create a calibration curve)
Using terephthalonitrile as a standard substance, each of the following model compounds (A), (B), and (C) is precisely weighed and mixed at an arbitrary ratio, and then pulverized with KBr powder. After being molded into a tablet, the infrared absorption spectrum was measured using an infrared spectrophotometer (FT / IR-410 manufactured by JASCO Corporation). The area of the absorption band of 2240～2260Cm ^-1 nitrile group resulting from terephthalonitrile of standards in the obtained spectrum, the model compound absorption band of 1630～1680Cm ^-1 urea groups (A), the model The area ratio of the 1680 to 1725 cm ⁻¹ absorption band of the isocyanuric group of the compound (B) and the 1730 to 1755 cm ⁻¹ absorption band of the urethane group of the model compound (C) were obtained, respectively, and the relationship between the area ratio and the mass ratio of the sample A calibration curve was created. The standard substances terephthalonitrile, model compound (A), and model compound (C) were all manufactured by Tokyo Chemical Industry Co., Ltd., and model compound (B) was manufactured by a known method. It was.
Model compound (A)
Model compound (B)
Model compound (C)
Reference material

(Measurement of bonding group concentration)
The microcapsule type curing agents obtained in Examples 1 to 8 and Comparative Examples 1 and 2 were washed with methanol and filtered to remove components other than the shell and isolate the shell. After completely removing and drying methanol at a temperature of 50 ° C. or less, 3 mg of terephthalonitrile as a standard substance was added to 1 g of this shell, and pulverized and mixed in an agate mortar. The obtained mixture was pulverized together with KBr powder, and the infrared absorption spectrum was measured using a tablet molding machine. Using the obtained spectrum chart and the calibration curve prepared by the above method, the concentration ratio was determined by determining the concentration of the bonding group (x), (y), (z) in the sample.

(Evaluation of curing characteristics of microcapsule type curing agent)
70 parts by mass of a bisphenol A type epoxy resin (AER250 manufactured by Asahi Kasei Chemicals Co., Ltd., epoxy equivalent 185 g / eq) was blended with 30 parts by mass of the microcapsule type curing agent, and the gel time on a 130 ° C. hot plate was measured. A gel time of 90 seconds or less was evaluated as 、, a case where the gel time was from 90 seconds to 120 seconds was evaluated as ◯, and a gel time exceeding 120 seconds was evaluated as ×.

(Evaluation of solvent resistance of microcapsule type curing agent)
A sample in which 70 parts by mass of a bisphenol A type epoxy resin (epoxy equivalent 185 g / eq) is mixed with 30 parts by mass of a microcapsule type curing agent, and mixed with 15 parts by mass of toluene and 5 parts by mass of ethyl acetate is prepared at 40 ° C. The sample was heated for 6 hours, and the viscosity of the sample was measured before and after heating and evaluated by the viscosity increase ratio. The viscosity was measured at 25 ° C. using a BM viscometer. The case where the rate of increase in viscosity is less than 2 times is indicated as ◯, the case where it is 2 times or more and less than 5 times is Δ, and the case where it is 5 times or more is indicated as x.

(Evaluation of solvent resistance of masterbatch type microcapsule type curing agent)
A sample in which bisphenol A type epoxy resin (epoxy equivalent 185 g / eq) is mixed so that the core agent: epoxy resin = 30: 70 (mass ratio) is mixed with 15 parts by mass of toluene and 5 parts by mass of ethyl acetate is prepared. The sample was heated at 40 ° C. for 6 hours, and the viscosity of the sample was measured before and after the heating, and evaluated by the viscosity increase ratio. The viscosity was measured at 25 ° C. using a BM viscometer. The case where the rate of increase in viscosity is less than 2 times is indicated as ◯, the case where it is 2 times or more and less than 5 times is Δ, and the case where it is 5 times or more is indicated as x.

(Production Example 1) Synthesis of amine adduct (1) 2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) and bisphenol A type were added to 50 g of a mixture of n-butanol and toluene in a separable flask at a mass ratio of 1/1. Epoxy resin (epoxy equivalent 176 g / eq) was added at a molar ratio of 1/1 and reacted at 80 ° C. Thereafter, the solvent was distilled off together with the solvent under reduced pressure until the content of 2-methylimidazole was 0.5% by mass or less, and after cooling to room temperature, a solid amine adduct (1) was obtained.

(Production Example 2) Synthesis of Amine Adduct (2) 1,2-Dimethylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) and phenyl were added to 50 g of a separable flask mixed with n-butanol and toluene at a mass ratio of 1/1. Glycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) was added at a molar ratio of 1/1 and reacted at 80 ° C. Thereafter, the solvent is distilled off together with the solvent under reduced pressure until the content of 1,2-dimethylimidazole reaches 0.5% by mass. After cooling to room temperature, the solid amine adduct (2) (represented by the general formula (1) is used. (Corresponding to a compound having a structure in the molecule).

(Production Example 3) Synthesis of Amine Adduct Particles (1) The obtained amine adduct (1) and sodium toluenesulfinate (manufactured by Tokyo Chemical Industry Co., Ltd.) were placed in a separable flask at a mass ratio of 90/10 and dissolved in methanol. I let you. Methanol was distilled off, and further drying was performed under reduced pressure to completely remove methanol. The obtained solid was jet mill pulverized to obtain amine adduct particles (1) having an average particle diameter of 2 μm.

(Production Example 4) Synthesis of amine adduct particles (2) Amine adduct particles having an average particle diameter of 2 µm were prepared in the same manner as in Production Example 3 except that the mass ratio of amine adduct (1) and sodium toluenesulfinate was 80/20. (2) was obtained.

(Production Example 5) Synthesis of amine adduct particles (3) Amine adduct particles having an average particle diameter of 2 µm were prepared in the same manner as in Production Example 3 except that the mass ratio of amine adduct (1) and sodium toluenesulfinate was 60/40. (3) was obtained.

Production Example 6 Synthesis of Amine Adduct Particles (4) Amine adduct particles (4) having an average particle diameter of 2 μm were obtained in the same manner as in Production Example 4 except that sodium methoxide was used instead of sodium toluenesulfinate. It was.

(Production Example 7) Synthesis of amine adduct particles (5) An average particle diameter of 2 μm was obtained in the same manner as in Production Example 4 except that the amine adduct (2) obtained in Production Example 2 was used instead of using sodium toluenesulfinate. Amine adduct particles (5) were obtained.

Production Example 8 Synthesis of Amine Adduct Particle (6) The amine adduct (1) obtained in Production Example 1 was crushed by jet mill to obtain amine adduct particles (6) having an average particle size of 2 μm.
Table 1 summarizes the amine adduct particles obtained in Production Examples 3 to 8.

Example 1 Synthesis of Microcapsule Type Curing Agent (1) 45 g of amine adduct particles (1) obtained in Production Example 3 and 171 g of cyclohexane were added to a separable flask, heated to 50 ° C., and then MR-200. 3 g of polymethylene phenylene polyisocyanate (manufactured by Nippon Polyurethane Co., Ltd.) was added for reaction, and then 1.2 g of water was added for further reaction. After completion of the reaction, the suspension was filtered, and the recovered powder was washed with cyclohexane and dried under reduced pressure to obtain a microcapsule type curing agent (1). Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Example 2) Synthesis of microcapsule type curing agent (2) In Example 1, a microcapsule type curing agent (2) was used in the same manner except that amine adduct particle (2) was used instead of amine adduct particle (1). 2) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Example 3) Synthesis of microcapsule type curing agent (3) In Example 1, a microcapsule type curing agent (3) was used in the same manner except that amine adduct particle (3) was used instead of amine adduct particle (1). 3) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

Example 4 Synthesis of Microcapsule Type Curing Agent (4) In Example 2, the same procedure was followed except that xylylene diisocyanate was used instead of MR-200 (manufactured by Nippon Polyurethane Co., Ltd., polymethylene phenylene polyisocyanate). A capsule-type curing agent (4) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Example 5) Synthesis of microcapsule-type curing agent (5) In Example 2, the same procedure as in Example 2, except that toluene diisocyanate was used instead of MR-200 (manufactured by Nippon Polyurethane Co., Ltd., polymethylene phenylene polyisocyanate). A capsule-type curing agent (5) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Example 6) Synthesis of microcapsule-type curing agent (6) A microcapsule-type curing agent (Example 6) except that amine adduct particles (4) were used instead of amine adduct particles (1). 6) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Example 7) Synthesis of microcapsule type curing agent (7) In Example 1, a microcapsule type curing agent (in the same manner as Example 1 except that amine adduct particle (5) was used instead of amine adduct particle (1)). 7) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

Example 8 Synthesis of Masterbatch Type Microcapsule Type Curing Agent (8) 200 g of bisphenol A type epoxy resin (epoxy equivalent 176 g / eq), 100 g of amine adduct particles (2), 2.7 g of water, MR-200 6.7 g (manufactured by Nippon Polyurethane Co., Ltd., polymethylene phenylene polyisocyanate) was added and reacted while stirring at 40 ° C. to obtain a master batch type microcapsule type curing agent (8). Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Comparative Example 1)
To the separable flask, 45 g of the amine adduct particles (6) obtained in Production Example 8 and 171 g of cyclohexane were added, heated to 50 ° C., 1.2 g of water was added, and the mixture was stirred for 10 minutes. After that, 3 g of MR-200 (manufactured by Nippon Polyurethane Co., Ltd., polymethylene phenylene polyisocyanate) was added and reacted. After the reaction was completed, the suspension was filtered, and the recovered powder was washed with cyclohexane and dried under reduced pressure. A capsule-type curing agent (1) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

(Comparative Example 2)
45 g of the amine adduct particles (1) obtained in Production Example 3 and 171 g of cyclohexane were added to the separable flask, heated to 50 ° C., 1.2 g of water was added, and the mixture was stirred for 10 minutes. After that, 3 g of MR-200 (manufactured by Nippon Polyurethane Co., Ltd., polymethylene phenylene polyisocyanate) was added and reacted. After the reaction was completed, the suspension was filtered, and the recovered powder was washed with cyclohexane and dried under reduced pressure. A capsule-type curing agent (1) was obtained. Using the obtained microcapsule type curing agent, the measurement of the bonding group concentration, the evaluation of the solvent resistance, and the evaluation of the curing characteristics were performed by the above-described methods. The results obtained are summarized in Table 2.

MR-200: Polymethylene phenylene polyisocyanate manufactured by Nippon Polyurethane Co., Ltd. XDI: xylylene diisocyanate TDI: tolylene diisocyanate

(Example of production of conductive film)
10 parts by mass of bisphenol A type epoxy resin (AER-2603 manufactured by Asahi Kasei Chemicals), 6 parts by mass of phenol novolac resin (manufactured by Showa Polymer Co., Ltd., trade name “BRG-558”), synthetic rubber (trade name “manufactured by ZEON Corporation” 4 parts by mass of Nipol 1072 ”(weight average molecular weight 300,000) were dissolved in 20 parts by mass of a 1: 1 (mass ratio) mixed solvent of methyl ethyl ketone and butyl cellosolve acetate. In this solution, 74 parts by mass of silver powder was mixed and further kneaded by a three-roll. To this, 40 parts by mass of the master batch type microcapsule type curing agent (8) obtained in Example 8 was further added and mixed uniformly to obtain a conductive adhesive. Using the obtained conductive adhesive, it was cast on a polypropylene film having a thickness of 40 μm and dried and semi-cured at 80 ° C. for 60 minutes to obtain a conductive film having a conductive adhesive layer having a thickness of 35 μm. . Using this conductive film, the conductive adhesive layer was transferred to the back surface of the silicon wafer on a heat block at 80 ° C. Furthermore, when the silicon wafer was fully diced and a semiconductor chip with a conductive adhesive was bonded and cured to the lead frame on a heat block at 200 ° C. for 3 minutes, there was no problem of chip conductivity.

(Example of production of conductive paste)
85 parts by mass of bisphenol A type epoxy resin (AER-2603 manufactured by Asahi Kasei Chemicals Co., Ltd.), 45 parts by mass of the master batch type microcapsule type curing agent (8) obtained in Example 8, and an average particle diameter of 14 μm, 150 g of flaky silver powder having an aspect ratio of 11 (manufactured by Tokuru Chemical Laboratory Co., Ltd.) and a nickel powder having an average particle diameter of 10 μm and an aspect ratio of 9 (manufactured by High Purity Chemical Co., Ltd., trade name “NI11010104”) 60 g was added, stirred until uniform, and then uniformly dispersed with a three roll to obtain a conductive paste. The obtained conductive paste was screen-printed on a polyimide film substrate having a thickness of 1.4 mm, and then heat-cured at 200 ° C. for 1 hour. As a result of measuring the conductivity of the obtained wiring board, it was useful as a conductive paste.

(Example of production of anisotropic conductive film)
30 parts by mass of bisphenol A type epoxy resin (AER-6097 manufactured by Asahi Kasei Chemicals Co., Ltd., epoxy equivalent 42500 g / eq) and 30 parts by mass of phenoxy resin (manufactured by Toto Kasei, YP-50) are dissolved in 30 parts by mass of ethyl acetate, 40 parts by mass of the masterbatch type microcapsule-type curing agent (8) obtained in Example 8 and 5 parts by mass of conductive particles (crosslinked polystyrene plated with gold) of 8 μm were added and mixed uniformly. A liquid epoxy resin composition was obtained. This was applied onto a polyester film, and ethyl acetate was removed by drying at 70 ° C. to obtain an anisotropic conductive film. The obtained anisotropic conductive film was sandwiched between the IC chip and the electrode and subjected to thermocompression bonding on a hot plate at 210 ° C. for 30 seconds at 30 kg / cm ² . It was useful as a conductive material.

(Example of production of anisotropic conductive paste)
50 parts by mass of bisphenol A type epoxy resin (AER-6091 manufactured by Asahi Kasei Chemicals Co., Ltd., epoxy equivalent 480 g / eq), 40 parts by mass of bisphenol A type epoxy resin (AER2603 manufactured by Asahi Kasei Chemicals Co., Ltd.) and Micropearl Au-205 (Sekisui) Chemical, specific gravity 2.67) After mixing 5 parts by mass, 45 parts by mass of the masterbatch type microcapsule type curing agent (8) obtained in Example 8 was added and mixed evenly, A conductive paste was obtained. The obtained anisotropic conductive paste was applied on a low alkali glass having an ITO electrode. A ceramic tool at 230 ° C. was pressed and bonded to a test TAB (Tape Automated Bonding) film at a pressure of 2 MPa for 45 seconds. When the resistance value between the adjacent ITO electrodes was measured, it was useful as an anisotropic conductive paste.

(Example of production of insulating paste)
100 parts by mass of bisphenol F type epoxy resin (manufactured by Yuka Shell Epoxy Co., Ltd., trade name “YL983U”), 4 parts by mass of dicyandiamide, 100 parts by mass of silica powder, 10 parts by mass of phenylglycidyl ether as a diluent, and organic phosphoric acid After sufficiently mixing 1 part by mass of an ester (manufactured by Nippon Kayaku Co., Ltd., trade name “PM-2”), the mixture is further kneaded with three rolls. Furthermore, 45 parts by mass of the masterbatch type microcapsule type curing agent (8) obtained in Example 8 was added thereto, and further uniformly mixed, and subjected to vacuum defoaming and centrifugal defoaming treatments to obtain insulating properties. A paste was produced. Using the obtained insulating paste, the semiconductor chip was bonded to a resin substrate by heating and curing at 220 ° C. for 1 hour, and it was useful as an insulating paste.

(Example of production of insulating film)
180 parts by mass of phenoxy resin (trade name “YP-50” manufactured by Toto Kasei Co., Ltd.), 40 cresol novolac type epoxy resin (epoxy equivalent 200 g / eq, product name “EOCN-1020-80” manufactured by Nippon Kayaku Co., Ltd.) After mixing and uniformly dispersing 300 parts by mass, 300 parts by mass of spherical silica (average particle size: 2 μm, manufactured by Admatech Co., Ltd., trade name SE-5101) and 200 parts by mass of methyl ethyl ketone, the master obtained in Example 8 was prepared. 250 parts by mass of the batch type microcapsule type curing agent (8) is added and further stirred and mixed to obtain a solution containing the epoxy resin composition. The obtained solution is applied onto polyethylene terephthalate that has been subjected to a mold release treatment so that the thickness after drying is 50 μm, and is heated and dried in a hot-air circulating dryer to provide insulating properties for semiconductor adhesion. A film was obtained. The obtained insulating film for adhering semiconductors is cut together with the supporting substrate larger than the wafer size of 5 inches, and the resin film is aligned with the electrode part side of the wafer with bump electrodes. Next, a support substrate with a release treatment is sandwiched between them, and heat-pressed in vacuum at 85 ° C., 1 MPa, and a pressurization time of 15 seconds to obtain a wafer with an adhesive resin. Subsequently, it was observed that the resin element of the semiconductor element with the adhesive film was cut and separated using a dicing saw (DAD-2H6M manufactured by DISCO) at a spindle rotation speed of 30,000 rpm and a cutting speed of 20 mm / sec. The obtained film was useful as an insulating film.

(Example of production of coating material)
30 parts by mass of bisphenol A type epoxy resin (AER-2603 manufactured by Asahi Kasei Chemicals), 30 parts by mass of YP-50 as a phenoxy resin (manufactured by Tohto Kasei), methyl ethyl ketone solution of methoxy group-containing silane-modified epoxy resin (Arakawa Chemical Industries, Ltd.) 50 parts by weight of the product name “Composeran E103”), 30 parts by weight of the master batch type microcapsule type curing agent (8) obtained in Example 8, and diluted to 50% by weight with methyl ethyl ketone. A mixed solution was prepared. The prepared solution is applied onto a release PET (polyethylene terephthalate) film (SG-1 manufactured by Panac Co., Ltd.) using a roll coater, dried and cured at 150 ° C. for 15 minutes, and a semi-cured resin with a release film (Dry film) A film thickness of 100 μm was prepared. These dry films were heat-pressed on the above copper-clad laminate at 120 ° C. for 15 minutes at 6 MPa, then returned to room temperature to remove the release film and cured at 200 ° C. for 2 hours. A useful coating material was obtained.

(Example of production of coating composition)
30 parts by mass of titanium dioxide and 70 parts by mass of talc are blended in 45 parts by mass of bisphenol A type epoxy resin (AER-6091 manufactured by Asahi Kasei Chemicals Corporation, epoxy equivalent 480 g / eq), and methyl isobutyl ketone / xylene 1: 1 Add 140 parts by mass of the mixed solvent, stir and mix to make the main agent. To this, 40 parts by mass of the master batch type microcapsule type curing agent (8) obtained in Example 8 was added and dispersed uniformly to obtain a useful epoxy coating composition.

(Example of production of prepreg)
15 parts by mass of novolac type epoxy resin (EP ICLON N-740 manufactured by Dainippon Ink & Chemicals, Inc.), 40 parts by mass of bisphenol F type epoxy resin (Epicoat 4005 manufactured by JER) in a flask in an oil bath at 130 ° C. Dissolve and mix 20 parts by mass of bisphenol A type liquid epoxy resin (AER2603 manufactured by Asahi Kasei Chemicals) and cool to 80 ° C. Further, 25 parts by mass of the masterbatch type microcapsule type curing agent (8) obtained in Example 8 is added and mixed with sufficient stirring. The resin composition cooled to room temperature was applied onto a release paper with a resin basis weight of 162 g / m ² using a doctor knife to obtain a resin film. Next, a CF cloth made by Mitsubishi Rayon (model number: TR3110, weight per unit area: 200 g / m ² ) obtained by plain weaving carbon fiber having an elastic modulus of 24 ton / mm ² at 12.5 pieces / inch is layered on the resin film to obtain a resin composition. After impregnating the carbon fiber cloth, a polypropylene film was stacked and passed between a pair of rolls having a surface temperature of 90 ° C. to prepare a cloth prepreg. The resin content was 45% by mass. The obtained prepreg is further laminated with the fiber direction aligned, and molded under a curing condition of 150 ° C. for 1 hour to obtain an FRP molded body using carbon fibers as reinforcing fibers. The produced prepreg is useful. Met.

(Example of production of thermally conductive epoxy resin composition)
90 parts by mass of bisphenol A type epoxy resin (AER2603 manufactured by Asahi Kasei Chemicals), 40 parts by mass of 50% methyl ethyl ketone solution of phenol novolac resin (Arakawa Chemical Co., Ltd., trade name “Tamanor 759”) as a curing agent for epoxy resin Then, 15 parts by mass of scaly graphite powder (trade name HOPG manufactured by Union Carbide Corporation) was stirred until uniform, and then uniformly dispersed by three rolls. Furthermore, 25 parts by mass of the masterbatch type microcapsule type curing agent (8) obtained in Example 8 is added and mixed with sufficient stirring. The obtained conductive paste was used to mount a semiconductor chip (1.5 mm square, thickness 0.8 mm) on a Cu lead frame and heat cured at 160 ° C. for 30 minutes to obtain an evaluation sample. The thermal conductivity of the obtained sample is measured by a laser flash method. That is, when the thermal conductivity K was determined from the measured thermal diffusivity α, specific heat Cp, and density σ from the following equation, K = α × Cp × σ, K was 5 × 10 ⁻³ Cal / cm · sec · It was above the temperature and was useful as a heat conductive paste.

  The microcapsule type curing agent of the present invention includes an adhesive and / or a bonding paste, a bonding film, a conductive material, an anisotropic conductive material, an insulating material, a sealing material, a coating material, a coating composition, a prepreg, and a thermal conductivity. It has industrial applicability as a material.

Claims (9)

A microcapsule type curing agent for epoxy resin having a core containing a curing agent and a shell covering the core, wherein the shell has an isocyanuric group and has an infrared wave number of 1630 to 1680 cm ⁻¹ . absorbing binding groups x, binding group y which absorbs infrared wave number 1680~1725cm ^-1, has a binding group z which absorbs infrared wave number 1730~1755cm ^-1, the binding groups x in the shell, y, And the concentration of z and Cx, Cy, and Cz, respectively, Cy / (Cx + Cy + Cz) is 0.4 or more and less than 1, a microcapsule type curing agent for epoxy resin.   The microcapsule type curing agent for epoxy resin according to claim 1, wherein the Cy / (Cx + Cy + Cz) is 0.4 or more and 0.62 or less. The core is at least one selected from the group consisting of metal alkoxides, quaternary ammonium salts, tertiary alkyl phosphines, sulfinic acid compounds, and compounds having a structure represented by the following general formula (1) in the molecule. The microcapsule type curing agent for epoxy resin according to claim 1 or 2, comprising a seed compound.
(1)
(Wherein R ¹ , R ² , R ³ , and R ⁴ are each independently a hydrogen atom, a halogen group, an alkyl group having 1 to 20 carbon atoms that may contain a substituent, or an aromatic group that may contain a substituent. Group, an alkoxy group having 1 to 20 carbon atoms which may contain a substituent, or a phenoxy group which may contain a substituent.)   The core is at least one selected from the group consisting of metal alkoxides, quaternary ammonium salts, tertiary alkyl phosphines, sulfinic acid compounds, and compounds having a structure represented by the general formula (1) in the molecule. The microcapsule type curing agent for epoxy resin according to claim 3, comprising 0.1% by mass or more and 50% by mass or less of a seed compound.   The core is an amine curing agent, acid anhydride curing agent, phenol curing agent, mercaptan curing agent, boron halide curing agent, quaternary ammonium salt curing agent, urea curing agent and phosphine curing agent. The microcapsule type curing agent for epoxy resin according to any one of claims 1 to 4, comprising at least one curing agent selected from the group consisting of:   The microcapsule type curing agent for epoxy resin according to claim 5, wherein the core contains 50% by mass or more of an amine curing agent.   The microcapsule type curing agent for epoxy resin according to claim 6, wherein the amine curing agent is an imidazole compound or an imidazoline compound.   The curable epoxy resin composition containing the microcapsule type hardening | curing agent for epoxy resins of any one of Claims 1-7, and an epoxy resin. A cured product obtained by curing the composition according to claim 8.