JP2000001526A - Curable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-temperature rapid-curing epoxy resin composition excellent in storage stability and curable within a short time even at a low temperature. SOLUTION: There are provided a latent curing agent for an epoxy resin, comprising the reaction product obtained by reacting (A) an epoxy compound having more than one epoxy group on the average in the molecule with (B) a compound having at least one functional group selected among OH, SH, NH, NH2, COOH, and CONHNH2 and a tertiary amino in the molecule in the presence of 0.05-5.0 equivalents, per equivalent of the epoxy groups of compound A, of water and a curable epoxy resin composition prepared by adding such a curing agent to an epoxy compound having more than one epoxy group on the average in the molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a latent curing agent for an epoxy resin and a curable epoxy resin composition containing the same, and more particularly, to an epoxy which imparts storage stability and low-temperature rapid curing. The present invention relates to a resin curing agent and a curable epoxy resin composition containing the same, which has excellent storage stability and low-temperature rapid curing properties.

[0002]

2. Description of the Related Art With recent remarkable developments in the field of electronics, the degree of integration of semiconductor device circuits has rapidly increased, and mass production has become possible. I have. Further, with the spread of these electronic devices, improvement of workability and cost reduction in mass production have become important issues. In addition, even in epoxy resins which have been used as adhesives for these electronic devices, and latent curing agents for epoxy resins, higher performances of various physical properties are further required. The application of the epoxy resin is, of course, not limited to this.

There are two types of epoxy resin compositions: a two-part type in which a main component epoxy resin and a curing agent are mixed immediately before use; and a one-part type in which a curing agent is preliminarily mixed with the main component epoxy resin. Prevent compounding mistakes, machine automation,
One-liquid type is preferred because it can be made into a line. The one-pack type epoxy resin composition does not react with the epoxy resin compound at room temperature, but needs a curing agent having a property of initiating the reaction by heating and curing, that is, a so-called latent curing agent.

Several latent curing agents have been proposed so far, typical examples of which include dicyandiamide, dibasic dihydrazide, boron trifluoride amine complex salts, guanamines, melamine, imidazoles and the like. . However, epoxy resin compositions in which dicyandiamide, melamine, or guanamines are mixed with an epoxy compound have excellent storage stability, but have the disadvantage of requiring long-term curing at a high temperature of 150 ° C. or higher. It is also widely practiced to shorten the curing time by using these together with a curing accelerator, but the addition of the curing accelerator shortens the curing time of the curable epoxy resin composition, but its storage stability is remarkable. The disadvantage of being compromised arises. An epoxy resin composition containing dibasic dihydrazide or imidazole as a latent curing agent cures at a relatively low temperature but has poor storage stability. Boron trifluoride amine complex has high hygroscopicity and adversely affects various properties of a cured product of an epoxy resin composition containing the same. In view of such a current situation, there is a strong demand for a latent curing agent for an epoxy resin which provides an epoxy resin composition having excellent storage stability and low-temperature rapid curing properties.

To improve these points, Japanese Patent Application Laid-Open
JP-A-56-155222 and JP-A-57-100127 disclose a curing agent obtained by adding an epoxy compound to a dialkylamine, and JP-A-59-53526 discloses a curing method obtained by adding an epoxy resin to an amino alcohol or aminophenol. Agents have been proposed. Also, U.S. Pat.
No. 4,268,656 proposes a curing agent in which an epoxy compound is added to a secondary amino group of an imidazole compound or N-methylpiperazine.

[0006] However, the above-mentioned curing agents do not sufficiently impart storage stability and low-temperature curability to the epoxy resin composition containing the curing agent. In particular, the storage stability of a composition using a reactive diluent such as a bisphenol F epoxy compound, a monoepoxy compound, and a diepoxy compound having relatively high reactivity was not satisfactory.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a latent curing agent which provides an epoxy resin composition having excellent storage stability and low-temperature quick-curing properties, and is further obtained by mixing this with an epoxy compound. An object of the present invention is to provide a curable epoxy resin composition, which retains good storage stability and can be cured at a relatively low temperature, that is, 80 to 120 ° C. in a short time. I do.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above various problems, and as a result, have found that OH groups, SH
A compound having a tertiary amino group and a functional group capable of reacting with an epoxy compound, such as a group, NH group, NH ₂ group, COOH group, or CONHNH ₂ group, is obtained by an addition reaction with an epoxy compound in the presence of water. The addition reaction product was found to be a curable epoxy resin composition obtained by mixing this with an epoxy compound, and was found to be excellent in storage stability and low-temperature quick-curability, and based on such findings, completed the present invention. Reached.

That is, the present invention provides (A) an epoxy compound having an average of more than one epoxy group in a molecule;
(B) OH group, SH group, NH group, NH ₂ group, C
A compound having both a tertiary amino group and at least one functional group selected from an OOH group and a CONHNH ₂ group, that is, a compound having two types of epoxy group 1 of compound (A)
The present invention relates to a latent curing agent for an epoxy resin comprising a reaction product obtained by reacting in the presence of water in a ratio of 0.05 equivalent to 5.0 equivalent to the equivalent. Incidentally, regarding the equivalent relation between the epoxy group and water, it is added that one molecule of water corresponds to one epoxy group.

The present invention also provides (A) an epoxy compound having an average of more than one epoxy group in a molecule;
(B) OH group, SH group, NH group, NH ₂ group, C
A compound having at least one functional group selected from an OOH group and a CONHNH ₂ group and a tertiary amino group,
(C) at least one functional group selected from an NH ₂ group and a CONHNH ₂ group in the molecule, or OH in the molecule
Group, SH group, NH group, NH ₂ group, COOH group and CO
A compound having at least two functional groups selected from NHNH ₂ groups (excluding a compound having an epoxy group or a tertiary amino group in the molecule), that is, a compound of the formula (A) The present invention relates to a latent curing agent for an epoxy resin comprising a reaction product obtained by reacting in the presence of water in a ratio of 0.05 equivalent to 5.0 equivalent to 1 equivalent of a group.

Further, the present invention provides, as essential components, (x) an epoxy compound having an average of more than one epoxy group in a molecule and (y) the latent curing agent for epoxy resin as an essential component. The present invention relates to a curable epoxy resin composition which also contains an inorganic filler.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below.

The compound (A) which is one of the raw materials for the synthesis reaction of the latent curing agent for an epoxy resin of the present invention, that is, the epoxy compound having an average of more than one epoxy group in the molecule, includes: There is no particular limitation, and any epoxy compound having an average of more than one epoxy group in the molecule may be used.

For example, an epoxy compound having on average more than one group represented by any of the following general formulas (1) to (3) in a molecule can be mentioned. Further, an epoxy compound having an average of more than one epoxy group in the molecule directly bonded to a carbon atom forming an alicyclic hydrocarbon ring and / or an epoxy group on the alicyclic hydrocarbon ring may be used. Furthermore, an epoxy compound having two or more of these epoxy groups in a molecule and having a total of more than one on average can also be used.

[0015]

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(This is a substituted or unsubstituted glycidyl ether group wherein Z is a hydrogen atom, a methyl group or an ethyl group.)

[0017]

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(This is a substituted or unsubstituted glycidyl ester group wherein Z is a hydrogen atom, a methyl group or an ethyl group.)

[0019]

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(This is an N-substituted substituted or unsubstituted 1,2-epoxypropyl group wherein Z is a hydrogen atom, a methyl group or an ethyl group.)

Examples of the epoxy compound having more than one substituted or unsubstituted glycidyl ether group represented by the general formula (1) in a molecule include bisphenol A, bisphenol F, bisphenol S, catechol, and the like. Resorcinol, phenol novolak resin,
Reacting a polyhydric phenol compound such as a resole resin, or a polyhydric alcohol compound such as glycerin, polyethylene glycol, a compound obtained by an addition reaction of a polyhydric phenol compound with an alkylene oxide having 2 to 4 carbon atoms with epihalohydrin. And substituted or unsubstituted glycidyl ether compounds.

Examples of the epoxy compound having more than one substituted or unsubstituted glycidyl ester group represented by the above general formula (2) in the molecule include aliphatic polyvalent compounds such as adipic acid and sebacic acid. Substituted or unsubstituted glycidyl ester compounds obtained by reacting a carboxylic acid compound or an aromatic polycarboxylic acid such as phthalic acid or terephthalic acid with epihalohydrin can be exemplified.

Then, N represented by the general formula (3)
Epoxy compounds having an average of more than one substituted or unsubstituted 1,2-epoxypropyl group in a molecule include:
For example, a substituted or unsubstituted glycidylamine compound obtained by reacting epihalohydrin with 4,4′-diaminodiphenylmethane, aniline, m-aminophenol or the like can be mentioned.

Further, an epoxy compound having an average of more than one epoxy group on the alicyclic hydrocarbon ring and / or an epoxy group directly bonded to a carbon atom forming the alicyclic hydrocarbon ring in a molecule is preferable. For example, an epoxy compound represented by the following general formula (4) or (5) can be mentioned.

[0025]

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(Y represents an optionally substituted monocyclic, polycyclic or bridged hydrocarbon ring having 2 to 8 carbon atoms)

[0027]

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(Y is the same as in the above general formula (4).)

As specific examples of the epoxy compound represented by the general formula (5), the following formulas (5-1) to (5-8)
The following can be exemplified.

[0030]

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Epoxy compounds having two or more of these epoxy groups in the molecule and having a total of more than one on the average include hydroxycarboxylic acids such as p-oxybenzoic acid and β-oxynaphthoic acid. Examples include a substituted or unsubstituted glycidyl ether ester compound obtained by reacting an acid with epihalohydrin, and a compound having a glycidyl ether group and an alicyclic epoxy group in a molecule, such as a compound represented by the following formula (6). be able to.

[0032]

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These epoxy compounds may contain a monoepoxy compound as long as the effects of the present invention are not impaired. As the monoepoxy compound, for example,
Butyl glycidyl ether, phenyl glycidyl ether, p-tert-butyl phenyl glycidyl ether, sec-
Monoepoxy compounds such as butylphenyl glycidyl ether and glycidyl methacrylate can be mentioned.

The epihalohydrin is, for example, represented by the following general formula (7), for example, epichlorohydrin, epibromohydrin, 1,2-epoxy-2-methyl-
Examples thereof include 3-chloropropane and 1,2-epoxy-2-ethyl-3-chloropropane.

[0035]

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(Z represents a hydrogen atom, a methyl group or an ethyl group, and X represents a halogen atom.)

The compounds (A) described above may be used alone or in combination of two or more.

The compound (B) which is another raw material for the synthesis reaction of the latent curing agent for epoxy resin of the present invention, that is, OH group, SH group, NH group, NH ₂ group, CO 2
At least one selected from an OH group and a CONHNH ₂ group
The compound having both functional groups and a tertiary amino group is represented, for example, by the following general formula (8).

[0039]

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(Where W is an OH group, an SH group, an NH group,
A NH ₂ group, a COOH group or a CONHNH ₂ group, wherein R ¹ and R ² each independently represent an aralkyl group such as an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, and a benzyl group; Or a partial carbon atom in the carbon chain of each of the above groups was substituted with another atom, for example, oxygen, or a hydrogen atom of the carbon chain was substituted with a halogen or a functional group represented by W above. R ³ is a divalent residue of the same group as R ¹ and R ² described above. R ¹ and R ² or R ¹ , R ²
And R ³ may combine with each other to form a ring.

As the compound (B), for example, a compound containing a tertiary amino group in a heterocyclic ring as shown by the following general formula (9), (10) or (12) is also effective. It can be mentioned as.

[0042]

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(Where R⁴, R⁵, R⁶And R
⁷Are each independently a hydrogen atom, in the above general formula (8)
R shown¹And R²Each group, alkyl group or
Is an aryl group optionally substituted with an aryl group,
Is a functional group represented by W in the general formula (8).
R⁷Is a hydrogen atom except when is a hydrogen atom⁴, R⁵, R
⁶And R⁷At least one of the functional groups represented by W
Or a group having a functional group represented by W. Also, R
⁷Is also a hydrogen atom,⁴, R⁵And R ⁶
Has a functional group represented by W or a functional group represented by W
Group. )

[0044]

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(Wherein, R ⁸ , R ⁹ and R ¹¹ are each independently a hydrogen atom, R ¹¹ represented by the above general formula (8)
¹ and the same groups as R ² , or an aryl group optionally substituted with an alkyl group or an aryl group,
R ¹⁰ is a divalent residue of the same group as R ¹ and R ² in the general formula (8), or an arylene group optionally substituted with an alkyl group or an aryl group, and X ′ is a hydrogen atom or The following equation (11):

[0046]

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(Wherein R ⁸ and R ⁹ are the same as those of the above-mentioned general formula (1)
And R ¹² is a hydrogen atom, the same groups as R ¹ and R ² shown in the general formula (8), or aryl optionally substituted with an alkyl group or an aryl group. Group. And when R ¹¹ and R ¹² are not both hydrogen atoms, at least one of R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² is a functional group represented by W or W Is a group having a functional group represented by R ¹¹ or R ¹²
When either or both are hydrogen atoms,
^{R 8, R 9, R 1} 0, R 11 and ^{R 12} may be a group having a functional group represented by a functional group or W represented by W).

[0048]

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(Wherein R ¹³ is a functional group represented by W or R ¹ or R ¹ containing a functional group represented by W therein)
It is the same group as ² . )

Such a compound (B), that is, a molecule
OH group, SH group, NH group, NH ₂Group, COOH group
And CONHNH₂At least one function selected from the group
Specific examples of the compound having both a group and a tertiary amino group include:
For example, 2-dimethylaminoethanol, 1-methyl-
2-dimethylaminoethanol, 1-phenoxymethyl
-2-dimethylaminoethanol, 2-diethylamino
Ethanol, 1-butoxymethyl-2-dimethylamino
Ethanol, 2-methylimidazole, 2-ethyl-4
-Methylimidazole, 2-undecylimidazole,
2-heptadecylimidazole, 2-phenylimidazo
, 1-aminoethyl-2-methylimidazole, 1
-(2-hydroxy-3-phenoxypropyl) -2-
Methyl imidazole, 1- (2-hydroxy-3-fe
Noxypropyl) -2-ethyl-4-methylimidazo
1- (2-hydroxy-3-butoxypropyl)-
2-methylimidazole, 1- (2-hydroxy-3-
(Butoxypropyl) -2-ethyl-4-methylimidazo
, 1- (2-hydroxy-3-phenoxypropyl)
L) -2-phenylimidazoline, 1- (2-hydroxy
(C-3-butoxypropyl) -2-methylimidazoli
, 2-methylimidazoline, 2,4-dimethylimida
Zoline, 2-ethylimidazoline, 2-ethyl-4-me
Tilimidazoline, 2-benzylimidazoline, 2-f
Enylimidazoline, 2- (o-tolyl) -imidazoli
, Tetramethylene-bis-imidazoline, 1,1,3
-Trimethyl-1,4-tetramethylene-bis-imida
Zoline, 1,3,3-trimethyl-1,4-tetramethyl
Ren-bis-imidazoline, 1,1,3-trimethyl-
1,4-tetramethylene-bis-4-methylimidazoli
1,3,3-trimethyl-1,4-tetramethylene
-Bis-4-methylimidazoline, 1,2-phenylene
-Bis-imidazoline, 1,3-phenylene-bis-i
Midazoline, 1,4-phenylene-bis-imidazoli
1,4-phenylene-bis-4-methylimidazoli
2- (dimethylaminomethyl) phenol, 2,
4,6-tris (dimethylaminomethyl) phenol,
N-β-hydroxyethylmorpholine, 2-dimethyla
Minoethanethiol, 2-mercaptobenzimidazo
, 2-mercaptobenzothiazole, 2-mercapto
Pyridine, 4-mercaptopyridine, N, N-dimethyl
Aminobenzoic acid, N, N-dimethylglycine, nicotine
Acid, isonicotinic acid, picolinic acid, N, N-dimethyl
Lysine hydrazide, nicotinic hydrazide, isonicotiz
Acid hydrazide, dimethylaminopropylamine, die
Tylaminopropylamine, dipropylaminopropyl
Amine, dibutylaminopropylamine, dimethylami
Noethylamine, diethylaminoethylamine, dipro
Pillaminoethylamine, dibutylaminoethylamido
, N-aminoethylpiperazine, dimethylaminoethyl
Lupiperazine, diethylaminoethylpiperazine, etc.
I can do it.

The compound (B) is preferably a compound having at least one functional group selected from an OH group, an NH group and an NH ₂ group and a tertiary amino group.

Examples of such a compound include 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2-diethylaminoethanol, and 1-butoxymethyl-2-dimethyl. Aminoethanol, N-β-
Hydroxyethylmorpholine, 1- (2-hydroxy-
3-phenoxypropyl) -2-methylimidazole,
1- (2-hydroxy-3-phenoxypropyl) -2
-Ethyl-4-methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-butoxypropyl)-
Tertiary amino groups such as 2-ethyl-4-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-phenylimidazoline and 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazoline A tertiary amino group-containing phenol compound such as 2- (dimethylaminomethyl) phenol and 2,4,6-tris (dimethylaminomethyl) phenol;
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-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, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, N-aminoethyl Primary or secondary amino group-containing tertiary amine compounds such as piperazine, dimethylaminoethylpiperazine, diethylaminoethylpiperazine and the like can be mentioned.

Of these, particularly preferred are tertiary amino group-containing alcohol compounds and primary or secondary amino group-containing tertiary amine compounds.

More preferred as the tertiary amino group-containing alcohol compound is 1- (2-hydroxy-3-
Phenoxypropyl) -2-methylimidazole, 1-
(2-hydroxy-3-phenoxypropyl) -2-ethyl-4-methylimidazole, 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)
A 5- or 6-membered nitrogen-containing heterocyclic structure such as -2-methylimidazoline;
(Hydroxy-3-phenoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-ethyl-4-methylimidazole, 1-
Those having an imidazole skeleton such as (2-hydroxy-3-butoxypropyl) -2-methylimidazole and 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4-methylimidazole are preferred.

Further, the above-mentioned tertiary amine compound containing a primary or secondary amino group is more preferably 2-methylimidazole, 2-ethyl-4-methylimidazole,
2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-aminoethyl-2-methylimidazole, 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-methylimidazoline, 1,2-phenylene- Bis-imidazoline, 1,
5-membered rings such as 3-phenylene-bis-imidazoline, 1,4-phenylene-bis-imidazoline, 1,4-phenylene-bis-4-methylimidazoline, N-aminoethylpiperazine, dimethylaminoethylpiperazine, diethylaminoethylpiperazine and the like Or a compound having a 6-membered nitrogen-containing heterocyclic structure, in particular, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole,
Those having an imidazole skeleton such as 2-phenylimidazole and 1-aminoethyl-2-methylimidazole are preferred.

As the compound (B) described above, one kind may be used alone, and two or more kinds may be used in combination.
And can be reacted.

The compound (C) which is the remaining raw material in the synthesis reaction of the latent curing agent for epoxy resin of the present invention, that is, at least one functional group selected from NH ₂ and CONHNH ₂ groups in the molecule, or OH group in molecule, SH
Group, NH group, NH ₂ group, COOH group and CONHNH
Examples of the compound having at least two functional groups selected from _two groups (excluding compounds having an epoxy group or a tertiary amino group in the molecule) include, for example, piperazine,
Amine compounds such as aniline and cyclohexylamine;
Polybasic carboxylic acids such as adipic acid, phthalic acid, 3,9-bis (2-carboxyethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane; 1,2-dimercaptoethane; Polyhydric thiols such as 2-mercaptoethyl ether; hydrazide compounds such as phenylacetic acid hydrazide; amino acids such as alanine and valine; 2-mercaptoethanol, 1-mercapto-3-phenoxy-2-propanol, mercaptoacetic acid, N-methylethanol Amines, diethanolamine,
Compounds having two or more functional groups such as hydroxyaniline, N-methyl-o-aminobenzoic acid, anthranilic acid, sarcosine, hydroxybenzoic acid, lactic acid; pentaerythritol, sorbitol, trimethylolpropane;
Polyhydric alcohol compounds such as trimethylolethane and tris (hydroxyethyl) isocyanurate; polyhydric phenol compounds; and the like.

As the compound (C), a polyhydric phenol compound is particularly preferable, and examples thereof include bisphenol A, bisphenol F, bisphenol S, hydroquinone, catechol, resorcinol, pyrogallol, phenol novolak resin, and resol resin. be able to.

As the compound (C) described above, one kind may be used alone, and two or more kinds may be used in combination.
And (B).

The reaction ratio of each raw material compound in producing the latent curing agent for epoxy resin of the present invention is determined by reacting the latent curing agent for epoxy resin with the compound (A) and the compound (B). When the compound (B) is a compound having at least one of an OH group, an SH group, a COOH group and a CONHNH ₂ functional group and a tertiary amino group in the molecule, Hydrogen-containing functional groups (OH
Group, SH group, COOH group and CONHNH ₂ group) with respect to 1 equivalent of active hydrogen,
The ratio is 2.5 equivalents, preferably 0.9 to 1.5 equivalents.
If the epoxy group is less than 0.8 equivalent to 1 equivalent of active hydrogen, the obtained latent curing agent for epoxy resin has a low softening temperature, is difficult to pulverize, and is incorporated into the epoxy compound as a latent curing agent. However, if the storage stability is not sufficient, the softening temperature of the reactant will be too high if it is more than 2.5 equivalents. This is because the cured product is not uniform and becomes non-uniform. Compound (B)
Is a compound having at least one functional group selected from an NH group and an NH ₂ group and a tertiary amino group in the molecule, the reaction ratio is the active hydrogen-containing functional group (NH group and NH ₂ group) Is the ratio of 0.4 to 1.1 equivalents of the epoxy group of the compound (A) to 1 equivalent of the active hydrogen of the compound (A). If the amount is less than 0.4 equivalent, sufficient storage stability cannot be obtained when the epoxy compound is blended as a latent curing agent, while if it is more than 1.1 equivalent, gelation occurs during the addition reaction. Incidentally, regarding the equivalence relationship between active hydrogen and epoxy group, it is added that one active hydrogen corresponds to one epoxy group.

When a latent curing agent for an epoxy resin is produced using the compound (A), the compound (B) and the compound (C), the reaction ratio of each starting compound is as follows. OH group, SH group, COOH group and CO
At least one functional group selected from NHNH ₂ groups and 3
When the compound also has a secondary amino group, the epoxy group of the compound (A) is preferably 0.5 to 2.5 times equivalent, more preferably the sum of the active hydrogen equivalents of the compound (B) and the compound (C). 0.6 to 1.5 equivalents, and compound (B)
It is preferable to use the compound (C) in a molar amount of 2 times or less with respect to that of the compound (C). If the epoxy group of the compound (A) is less than 0.5 equivalent, sufficient storage stability cannot be obtained when blended with the epoxy compound as a latent curing agent, while if it is more than 2.5 equivalent, the reactant is softened. The temperature becomes high, and when incorporated into an epoxy compound as a latent curing agent, sufficient rapid curing properties are not exhibited, and the cured product becomes non-uniform. Further, when the amount of the compound (C) exceeds twice the amount of the compound (B), the curability is reduced. In the case of producing a latent curing agent for an epoxy resin using the three of the compounds (A), (B) and (C), the compound (B) is selected from an NH group and an NH ₂ group in the molecule. In the case of a compound having at least one functional group and a tertiary amino group, the reaction ratio is calculated based on the sum of the active hydrogen equivalents of the compounds (B) and (C) and the epoxy group of the compound (A) being 0.1%. 2-1.1
Double equivalent. When the epoxy group of the compound (A) is less than 0.2 equivalent, sufficient storage stability cannot be obtained when the epoxy compound is blended with the epoxy compound as a latent curing agent. This is because, when it is mixed with an epoxy compound as a latent curing agent, sufficient rapid curability is not exhibited and the cured product becomes non-uniform.

The two compounds (A) and (B) or the three compounds (A), (B) and (C) were added in an amount of 0.05 equivalent to 1 equivalent of the epoxy group of the compound (A). 5.
The latent curing agent for epoxy resin of the present invention can be obtained by reacting in the presence of water at a ratio of 0 equivalent or less, preferably 0.1 equivalent to 2.0 equivalents. Usually, the compounds (A), (B) and (C), which are raw materials, contain a small amount of water, but the effects as in the present invention cannot be obtained by themselves. As in the present invention, water is further added to the compound (A)
The latent curing agent for an epoxy resin of the present invention can be obtained by carrying out the reaction with a water content of 0.05 to 5.0 equivalents to the epoxy group of the present invention. Water is 0.0
If the equivalent is less than 5 equivalents, sufficient storage stability cannot be obtained when the obtained reactant is blended with the epoxy compound as a latent curing agent. They need to be removed, which is extra time and energy impractical.

The latent curing agent for epoxy resin of the present invention comprises
An addition reaction compound having an arbitrary softening temperature can be obtained by changing the types of the compounds (A), (B) and (C), the mixing ratio and the ratio of water, to obtain an addition reaction compound.
Those having a softening temperature of 0 to 180 ° C are preferred. When the softening temperature is lower than 60 ° C, when the epoxy resin is blended as a latent curing agent, the resulting resin composition has poor storage stability at room temperature, while when the softening temperature exceeds 180 ° C, sufficient curability is obtained. I can't get it.

The latent curing agent for epoxy resin of the present invention comprises:
For example, compound (A), compound (B), and water, or compound (A), compound (B), compound (C), and each component of water are sufficiently mixed and gelled at room temperature.
It can be obtained by completing the reaction at a temperature of １５０150 ° C., then cooling, solidifying and pulverizing. At this time, the reaction is performed in a solvent such as toluene, tetrahydrofuran, methyl ethyl ketone, or dimethylformamide,
The solvent may be removed, solidified, and ground. Water is completely dissolved in compound (A) and compound (B), or in compound (A), compound (B), compound (C), or those obtained by adding a solvent thereto. May be dispersed without being completely dissolved.

The latent curing agent for epoxy resin of the present invention comprises
Known curing agents such as acid anhydrides, dicyandiamide, hydrazide compounds, guanamines and melamines can be used in combination.

The latent curing agent for epoxy resin of the present invention comprises
As such or with the addition of known curing agents, they can be placed in circulation.

Further, the curable epoxy resin composition of the present invention comprises (x) an epoxy compound having an average of more than one epoxy group in a molecule and (y) the epoxy resin potential of the present invention described above. It is a resin composition containing a curing agent as an essential component.

Here, the epoxy compound (x) having an average of more than one epoxy group in the molecule is completely different from the compound (A), that is, the epoxy compound having an average of more than one epoxy group in the molecule. Similarly, various well-known compounds similar to those exemplified above can be mentioned.
The use amount (blending amount) of the latent curing agent for epoxy resin of the present invention in the resin composition of the present invention is preferably from 0.3 to 50 parts by weight based on 100 parts by weight of the epoxy compound (x). If the amount is less than 0.3 parts by weight, sufficient curability cannot be obtained,
On the other hand, when the amount exceeds 50 parts by weight, the performance of the cured product may be reduced. Further, other additives can be added to the curable epoxy resin composition of the present invention as necessary or desired. Examples of such additives include (z) fillers (inorganic fillers) such as alumina, silica, aerosil, calcium carbonate, aluminum hydroxide, magnesium hydroxide, talc, bentonite, and barium sulfate, acrylic oligomers, and silicones. And flow control agents, surface control agents, diluents, and flame retardants.

[0069]

EXAMPLES Next, the present invention will be described in more detail with reference to Production Examples and Examples, but the present invention is not limited thereto. The abbreviations of the raw materials used in Production Examples and Examples are as follows.

(A) an epoxy compound having an average of more than one epoxy group in the molecule; EP # 828: "Epicoat # 828" (trade name, Bisphenol A type epoxy resin (trade name, manufactured by Yuka Shell Epoxy Co., Ltd.) EP # 834: "Epicoat # 834" (trade name: Yuka Shell Epoxy Co., Ltd., bisphenol A type epoxy resin (epoxy equivalent 230-270)), EP # 1001: "Epicoat # 1001" (Product name: Bisphenol A type epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd. (epoxy equivalent: 450-500)), EP # 807: "Epicoat # 807" (Product name: Bisphenol F type epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd.) (Epoxy equivalents 160-175)).

(B) OH group, SH group, NH group,
A compound having at least one functional group selected from an NH ₂ group, a COOH group, and a CONHNH ₂ group and a tertiary amino group; DEAPA: diethylaminopropylamine (water content: 0.
16wt%), DEAE-OH: diethylaminoethanol (water content 0.18w
t%), 2PZL: 2-phenylimidazoline (water content 0.07wt
%), 2E4MZ: 2-ethyl-4-methylimidazole (water content: 0.
2MZ: 2-methylimidazole (water content 0.06wt%), PG-MZ: 1- (2-hydroxy-3-phenoxypropyl) -2-
Methyl imidazole (water content 0.04wt%), PG-EMZ: 1- (2-hydroxy-3-phenoxypropyl) -2-
Ethyl-4-methylimidazole (water content 0.28wt%), PG-PZL: 1- (2-hydroxy-3-phenoxypropyl) -2-
Phenylimidazoline (water content 0.04wt%), DMP-10: 2- (dimethylaminomethyl) phenol (water content 0.42wt%), DMP-30: 2,4,6-tris (dimethylaminomethyl) phenol (water content) 0.09wt%), SMZ: 2-mercapto-1-methylimidazole (water content
0.18 wt%), DMGH: N, N-dimethylglycine hydrazide (water content 0.
34 wt%), NA: nicotinic acid (water content 0.31 wt%).

(C) NH ₂ group and CONHNH in the molecule
At least one functional group or OH groups in the molecule selected from the ₂ group, SH group, NH group, NH ₂ group, compounds having at least two functional groups selected from COOH group and CONHNH ₂ group (provided that the molecular BA: bisphenol A (water content: 0.27 wt%) PNV: phenol novolak "SHONOL BRG-555"
(Showa Polymer Co., Ltd., hydroxyl equivalent 103, moisture content 0.57w
t%), PIP: anhydrous piperazine (water content 0.39wt%), PAAH: phenylacetic acid hydrazide (water content 0.22wt%)
%), AL: aniline (water content 0.14 wt%), HQ: hydroquinone (water content 0.25 wt%), DEA: diethanolamine (water content 0.09 wt%).

Production Example 1 (Production of Addition Product of DEAE-OH and Epikote # 828) "Epicoat # 828", 110.3 g (0.584 equivalent) and DEAE-OH,
39.1 g (0.334 equivalents), 10.5 g (0.583 equivalents) of water and 10.5 g (0.583 equivalents) were weighed into a beaker, and the temperature was gradually raised while stirring well at room temperature. Since the reaction rapidly progressed with heat generation around 70 ° C., the reaction mixture was cooled or heated so that the temperature of the reaction mixture became about 110 ° C., and reacted for 1 hour. After completion of the reaction, the mixture was cooled to room temperature to obtain a pale yellow solid. This addition reaction product was crushed and further pulverized to an average particle size of about 10 μm.
Powder was obtained. This is designated as Latent Curing Agent Sample No. 1 for Epoxy Resin.

Production Example 2 (Production of Addition Product of PG-MZ, DMP-30, BA and "Epicoat # 828") PG-MZ was placed in a 3,000 ml three-necked flask equipped with a reflux condenser and a stirrer. , 116.1g (0.5 equivalent) and DMP-30, 26.6g
(0.1 equivalent), BA, 57.1 (0.5 equivalent), water, 1.8 g (0.1 equivalent) and 500 ml of methyl ethyl ketone as a solvent were weighed, and heated and stirred, and 300 m of methyl ethyl ketone was added.
189 g (1.0 equivalent) of “Epicoat # 828” dissolved in l was added dropwise (about 3 hours). After completion of the dropwise addition, the mixture was further heated under reflux with stirring for 2 hours. Thereafter, the solvent methyl ethyl ketone was distilled off under reduced pressure, and the residue was cooled to room temperature to obtain a pale yellow solid. This addition reaction product was crushed and further pulverized to obtain a powder having an average particle size of about 10 μm. This is designated as Latent Curing Agent Sample No. 22 for Epoxy Resins.

Table 1 below shows sample numbers and raw material compositions of the latent curing agents for epoxy resins of the present invention produced according to Production Example 1 or Production Example 2.

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[Table 1]

[0077]

[Table 2]

Comparative Production Example 1 A reaction was carried out in exactly the same manner as in Production Example 1 except that water was not added, to obtain a pale yellow solid. This was coarsely crushed and further finely crushed to obtain a powder having an average particle size of about 10 μm. This is referred to as Comparative Sample No. 1.

Comparative Production Example 2 In a 3,000 ml three-necked flask equipped with a reflux condenser and a stirrer, 174.2 g (0.75 equivalent) of PG-MZ and 26.6 g of DMP-30 were added.
(0.1 equivalent), BA, 85.7 (0.75 equivalent), and 500 ml of methyl ethyl ketone as a solvent were weighed, and while heating and stirring, 189 g (1.0 equivalent) of “Epicoat # 828” dissolved in 300 ml of methyl ethyl ketone was added dropwise (about 1.0 equivalent). 3 hours).
After completion of the dropwise addition, the mixture was further heated under reflux with stirring for 2 hours. Thereafter, the solvent methyl ethyl ketone was distilled off under reduced pressure, and the residue was cooled to room temperature to obtain a pale yellow solid. This addition reaction product was crushed and further pulverized to obtain a powder having an average particle size of about 10 μm. This is referred to as Comparative Sample No. 4.

Table 2 below shows the numbers of comparative samples produced according to Comparative Production Example 1 or Comparative Production Example 2 and their raw material compositions.

[0081]

[Table 3]

Examples 1 to 34 and Comparative Examples 1 to 5: The above-mentioned latent curing agents for epoxy resins were added to epoxy compounds at the ratios shown in Table 3 below and mixed to obtain curable epoxy resin compositions. Was. The curability (gel time) and storage stability of this composition were measured to evaluate its performance.

[0083]

[Table 4]

Preparation method of curable epoxy resin composition: Defoaming and mixing were carried out for 30 minutes under reduced pressure using a vacuum grinder (manufactured by Ishikawa Plant) at the ratios shown in Table 3 above.

Gel time: Yasuda-type gel timer (Co., Ltd.)
(Yasuda Seiki Seisaku-sho, Ltd.) at a predetermined temperature using about 2.5 g of the curable epoxy resin composition.

Storage stability: The curable epoxy resin composition was placed in a sealed container, stored in a thermostat at a predetermined temperature (40 ° C.), and the number of days until the fluidity disappeared was measured.

The results obtained are shown in Table 4 below for Examples and in Table 5 below for Comparative Examples.

[0088]

[Table 5]

[0089]

[Table 6]

Examples 35 to 36 and Comparative Examples 6 to 7: To examine the performance as a curing accelerator when the latent curing agent for epoxy resin of the present invention was used in combination with another latent curing agent, the following A curable epoxy resin composition was prepared by mixing at the ratios shown in Table 6, and the gel time was measured in the same manner as in Examples 1-34. In addition, the storage stability was measured by storing in a constant temperature bath at 50 ° C. and the number of days until the fluidity disappeared.

[0091]

[Table 7]

The results obtained are shown in Table 7 below.

[0093]

[Table 8]

Examples 37 to 38 and Comparative Examples 8 to 9:
In order to investigate the performance when the latent curing agent for epoxy resin of the present invention was used in combination with another latent curing agent, a curable epoxy resin composition was prepared by blending at the ratio shown in Table 8 below, and Gel time and storage stability were measured in the same manner as in Examples 1 to 34.

[0095]

[Table 9]

The results obtained are shown in Table 9 below.

[0097]

[Table 10]

From the above, it can be seen that the latent curing agent for epoxy resin of the present invention imparts very good storage stability and low-temperature rapid curing to the epoxy resin composition containing the same.

[0099]

According to the present invention, a curable epoxy resin composition having very good storage stability and curability at low temperature and fast curability can be easily obtained. The curable epoxy resin composition of the present invention has low-temperature fast-curing properties, and is excellent in heat resistance, electrical reliability, and the like, and is suitable for electronic applications such as semiconductor sealing resins, anisotropic conductive adhesive films, and conductive resins. .

Claims (6)

[Claims] 1. An epoxy compound having (A) an average of more than one epoxy group in a molecule; and (B) an OH compound in a molecule.
Group, SH group, NH group, NH ₂ group, COOH group and CON
At least one functional group selected from HNH ₂ groups and 3
A compound having a secondary amino group and a reaction product obtainable by reacting the compound (A) in the presence of water in a proportion of 0.05 to 5.0 equivalents to 1 equivalent of the epoxy group of the compound (A). A latent curing agent for epoxy resins, characterized by the following. 2. An epoxy compound having (A) an average of more than one epoxy group in the molecule, and (B) an OH compound in the molecule.
Group, SH group, NH group, NH ₂ group, COOH group and CON
A compound having at least one functional group selected from HNH ₂ groups and a tertiary amino group, and (C) at least one functional group selected from NH ₂ groups and CONHNH ₂ groups in the molecule, or OH group, SH group, NH group, NH
A compound having at least two functional groups selected from _two groups, a COOH group and a CONHNH ₂ group (excluding a compound having an epoxy group or a tertiary amino group in the molecule) and an epoxy group of the compound (A) A latent curing agent for an epoxy resin, comprising a reactant obtainable by reacting in the presence of 0.05 to 5.0 equivalents of water per equivalent. 3. The latent curing agent for an epoxy resin according to claim 2, wherein the compound (C) is a polyhydric phenol compound. 4. The latent curing agent for an epoxy resin according to claim 1, wherein the compound (B) is a tertiary amino group-containing phenol compound or a tertiary amino group-containing alcohol compound. . 5. An essential component comprising (x) an epoxy compound having an average of more than one epoxy group in a molecule and (y) the latent curing agent for an epoxy resin according to any one of claims 1 to 4. A curable epoxy resin composition characterized by containing. 6. The curable epoxy resin composition according to claim 5, further comprising (z) an inorganic filler.