JP2018141150A - Polyfunctional epoxy resin composition, and cured product obtained by curing the polyfunctional epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyfunctional epoxy resin composition that has low viscosity and is easy to mold and process, and also has a high glass transition temperature when cured, and a cured product obtained by curing the epoxy resin composition.SOLUTION: A polyfunctional epoxy resin composition contains a polyfunctional epoxy resin represented by general formula (1) (where, Rand Rindependently represent a methyl group, a methoxy group or a halogen atom. m and n independently represent an integer of 0-3), and an acid anhydride-based curing agent.SELECTED DRAWING: None

Description

The present invention relates to a polyfunctional epoxy resin composition and a cured product obtained by curing the polyfunctional epoxy resin composition. Moreover, it is related with the polyfunctional epoxy resin composition excellent in the moldability and workability especially.

Epoxy resins are excellent in heat resistance, adhesiveness, water resistance, mechanical strength, and electrical properties, so they are used in various fields such as adhesives, paints, materials for civil engineering and construction, and insulation materials for electrical and electronic equipment. It is used. In particular, in the electric / electronic field, it is widely used in insulating materials, laminated materials, sealing materials and the like.
Patent Document 1 discloses a polyfunctional epoxy resin based on a derivative of biphenyl, diphenylmethane, or diphenylsulfone. The curing agent used in the examples is diaminodiphenylmethane, and the cured product obtained by curing is characterized by high bending strength and adhesiveness and low water absorption.

Patent Document 2 discloses a curable resin composition containing a polyvalent glycidyl compound having a glycidyl group and a glycidyl ether group bonded to the same aromatic ring in the molecule, and a phenol-based curing agent. By using a phenolic curing agent, the crosslink density in the resin is increased, and heat resistance, rigidity, adhesiveness, etc. are excellent.
In recent years, especially for electrical and electronic equipment materials such as multilayer circuit boards, miniaturization of equipment,
With the progress of weight reduction and higher functionality, further improvements in multilayering, higher density, thickness reduction, weight reduction, reliability, moldability, and the like are required. As an epoxy resin with improved moldability and processability,
Patent Document 3 discloses a novel polyfunctional epoxy resin having a monocyclic alicyclic hydrocarbon as a partial structure.

Japanese Patent Laid-Open No. 63-142019 Japanese Patent Laying-Open No. 2015-127397 Japanese Patent Laid-Open No. 2006-204647

However, since the polyfunctional epoxy resin described in Patent Document 1 uses a solid amine-based curing agent, when the composition is a mixture of a polyfunctional epoxy resin and a curing agent, the curing agent is used at room temperature. There was a problem that it was difficult to dissolve. Further, if the composition is heated, the curing agent dissolves, but the curing reaction proceeds and the viscosity becomes high, so that molding and processing are difficult.

Moreover, since the curable resin composition described in Patent Document 2 has a high molecular weight of the phenolic curing agent, there is a problem that the viscosity is too high for molding and processing.
In addition, the polyfunctional epoxy resin composition described in Patent Document 3 has a lower viscosity than the epoxy resin compositions disclosed in Patent Document 1 and Patent Document 2, and has improved moldability and workability. The further improvement of the glass transition temperature (Tg) of the hardened | cured material formed by hardening | curing polyfunctional epoxy resin was calculated | required.

In order to solve the above problems, the present inventors have intensively studied the combination of the structure of a polyfunctional epoxy resin and an acid anhydride as a curing agent. As a result, the polyfunctional epoxy resin has a high glass transition temperature when cured. The composition has been found and the present invention has been completed.
That is, the gist of the present invention resides in the following [1] to [4].
[1] A polyfunctional epoxy resin composition containing a polyfunctional epoxy resin and an acid anhydride curing agent,
The polyfunctional epoxy resin is
The following general formula (1)

(In general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group or a halogen atom. M and n each independently represents an integer of 0 to 3.)
It is represented by
The acid anhydride curing agent is
The following general formula (2)

(In the general formula (2), R ^{3 to} R ⁶ each independently represent a hydrogen atom or a methyl group. X represents a single bond or a double bond.)
Or
The following general formula (3)

In (formula ^(3), R 3 ~R ⁶ have the same meanings as in formula (2) .R ⁷ is C 1 -C
Represents a divalent hydrocarbon group which may be branched to 3; X represents a single bond or a double bond. )
The polyfunctional epoxy resin composition characterized by being represented by any one of these.
[2] The polyfunctional epoxy resin according to [1], further comprising an inorganic filler, wherein the content of the inorganic filler is 50% by weight or more based on the content of all nonvolatile components of the polyfunctional epoxy resin composition. Composition.
[3] The polyfunctional epoxy resin composition according to [1] or [2], further comprising an imidazole curing accelerator.
[4] A cured product obtained by curing the polyfunctional epoxy composition according to any one of [1] to [3].

ADVANTAGE OF THE INVENTION According to this invention, the low viscosity polyfunctional epoxy resin composition which is easy to shape | mold and process can be provided.
Moreover, the hardened | cured material formed by hardening | curing the polyfunctional epoxy resin composition of this invention has a high glass transition temperature, and is excellent in heat resistance.

The polyfunctional epoxy resin composition of the present invention (hereinafter sometimes referred to as “the composition of the present invention”).
)
The following general formula (1)

(In general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group or a halogen atom. M and n each independently represents an integer of 0 to 3.)
A polyfunctional epoxy resin represented by
The following general formula (2)

(In the general formula (2), R ^{3 to} R ⁶ each independently represent a hydrogen atom or a methyl group. X represents a single bond or a double bond.)
Or
The following general formula (3)

In (formula ^(3), R 3 ~R ⁶ have the same meanings as in formula (2) .R ⁷ is C 1 -C
Represents a divalent hydrocarbon group which may be branched to 3; X represents a single bond or a double bond. )
It contains the acid anhydride type hardening | curing agent represented by either of these.
The polyfunctional epoxy resin and acid anhydride curing agent contained in the composition of the present invention will be described in detail below.

Further, the composition of the present invention may contain a curing accelerator, an inorganic filler, a solvent, other additives, etc. in addition to the polyfunctional epoxy resin and the acid anhydride curing agent. This will be described in detail.
<Multifunctional epoxy resin>
The polyfunctional epoxy resin contained in the polyfunctional epoxy resin composition of the present invention has the following general formula (1
).

(In general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group or a halogen atom. M and n each independently represents an integer of 0 to 3.)
In the general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group, or a halogen atom. From the viewpoint of improving the moldability by lowering the melting point of the polyfunctional epoxy resin, R ¹ and R ² are preferably methyl groups. From the viewpoint of imparting flame retardancy to a cured product obtained by curing the polyfunctional epoxy resin, R ¹ and R ² are preferably halogen atoms.

In General formula (1), m and n represent the integer of 0-3 each independently. By reducing the molecular weight of the polyfunctional epoxy resin and reducing the epoxy equivalent, the crosslink density of the cured product obtained by curing the epoxy resin is increased and the heat resistance is improved. ˜1 is preferable, and 0 is particularly preferable.
Since the polyfunctional epoxy resin contained in the composition of the present invention has such a structure in which rigid aromatic rings are directly bonded, it is considered that the effect of increasing the glass transition temperature (Tg) is obtained. .

The theoretical epoxy equivalent of the polyfunctional epoxy resin contained in the composition of the present invention is preferably larger from the viewpoint of imparting flexibility, and smaller from the viewpoint of improving heat resistance. Specifically, it is preferably 90 or more, more preferably 95 or more, and particularly preferably 100 or more. On the other hand, it is preferably 150 or less,
More preferably, it is 130 or less, and particularly preferably 110 or less. Here, the theoretical epoxy equivalent represents a value (unit is g / equivalent) obtained by dividing the molar mass of the molecule in the general formula (1) by the number of epoxy groups in the general formula (1).

  Below, the specific example of General formula (1) is shown.

  Among these, the following compounds are preferable.

Moreover, the manufacturing method of the polyfunctional epoxy resin contained in the composition of this invention is not specifically limited. For example, from a compound having an allyl group and a phenolic hydroxyl group, a method in which the phenolic hydroxyl group is glycidylated with epihalohydrin and then the allyl group is oxidized to form an epoxy ring, and after allyl groups have been allylated, It can be produced by a method of oxidizing to form an epoxy ring. Specifically, JP-A-63-142019.
It can manufacture by the method as described in gazette and Unexamined-Japanese-Patent No. 2006-204647.

Moreover, the polyfunctional epoxy resin represented by the general formula (1) may be used alone or in combination of two or more, and further, the polyfunctional epoxy resin represented by the general formula (1). You may use combining epoxy resins other than an epoxy resin.
When the polyfunctional epoxy resin represented by the general formula (1) and another epoxy resin are used in combination, the polyfunctional epoxy resin represented by the general formula (1) occupies the total amount of the epoxy resin in the composition of the present invention. The content of the polyfunctional epoxy resin is preferably 20% by weight or more, more preferably 40% by weight or more, and particularly preferably 60% by weight or more.

In the polyfunctional epoxy resin composition of the present invention, 1-2 of the four epoxy groups of the polyfunctional epoxy resin represented by the general formula (1) as impurities are carbon instead of epoxy groups. -It may contain an epoxy resin forming a carbon double bond. The content thereof is not particularly limited as long as the effects of the present invention are not impaired. However, in order to improve heat resistance, the content of these impurities is preferably small, and the content is preferably large in order to reduce the viscosity.

In general, epoxy resins often contain oligomers formed by the reaction of epoxy groups with hydroxyl groups derived from raw materials. Also in the polyfunctional epoxy resin composition of the present invention, the above-mentioned oligomer component derived from the polyfunctional epoxy resin represented by the general formula (1) or other epoxy resin which may be contained is included as an impurity. You may go out.
The content of other impurities can also be estimated by the epoxy equivalent, but the smaller the impurities, the better the processability of the composition containing the polyfunctional epoxy resin of the present invention and the heat resistance of the cured product of the present invention. . Therefore, the ratio of the epoxy equivalent of the polyfunctional epoxy resin of the present invention to the theoretical epoxy equivalent (epoxy equivalent of the mixture / theoretical epoxy equivalent) is usually 1.00 to 1.
. 40 is preferable, 1.00 to 1.25 is more preferable, and 1.00 to 1.15 is more preferable.

Moreover, since the polyfunctional epoxy resin represented by the general formula (1) is easy to be molded and processed, the shear viscosity at 150 ° C. is preferably 200 mPa · sec or less, and 100 m
It is more preferably at most Pa · sec, particularly preferably at most 50 mPa · sec.
When the polyfunctional epoxy resin represented by the general formula (1) is solid at 25 ° C., it is preferable that the melting point is low because of good workability and moldability. Specifically, it is preferably 120 ° C. or lower, more preferably 100 ° C. or lower, and further preferably 80 ° C. or lower.

Further, the chlorine content in the polyfunctional epoxy resin of the present invention is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and particularly preferably 100 ppm by mass or less in terms of Cl. When the content ratio of the chlorine component is large, the chlorine component remains in the obtained cured product, which may reduce the insulation of the cured product or corrode the metal wiring or the like that comes into contact.

<Acid anhydride curing agent>
The acid anhydride curing agent contained in the composition of the present invention has the following general formula (2):

(In the general formula (2), R ^{3 to} R ⁶ each independently represent a hydrogen atom or a methyl group. X represents a single bond or a double bond.)
Or the following general formula (3)

In (formula ^(3), R 3 ~R ⁶ have the same meanings as in formula (2) .R ⁷ is C 1 -C
Represents a divalent hydrocarbon group which may be branched to 3; X represents a single bond or a double bond. )
Represented by either By using these acid anhydride type curing agents, the viscosity of the composition of the present invention is lowered, and the effect of facilitating molding and processing is obtained.

In General formula (2), R < ³ > -R < ⁶ > represents a hydrogen atom or a methyl group each independently. From the viewpoint of improving the heat resistance of the cured product, R ^{3 to} R ⁶ are preferably hydrogen atoms, and from the viewpoint of reducing the viscosity and melting point of the acid anhydride curing agent and improving the moldability and workability. ,
R ^{3 to} R ⁶ are preferably methyl groups.
In the general formula (2), X represents a single bond or a double bond. From the viewpoint of suppressing the coloring of the cured product or improving the weather resistance, X is preferably a single bond, and the viewpoint of lowering the viscosity of the acid anhydride curing agent and improving the moldability and workability. Therefore, X is preferably a double bond.

In the general formula ^(3), R 3 to R ⁶ have the same meanings as ^R 3 to R ⁶ in the general formula (2).
In General formula (3), X is synonymous with X in General formula (2).
In the general formula (3), R ⁷ represents a divalent hydrocarbon group having 1 to 3 carbon atoms which may be branched. Examples of the divalent hydrocarbon group having 1 to 3 carbon atoms that may be branched include a methylene group, 1
, 1-ethylene group, 2,2-propylene group, 1,2-ethylene group, 1,3-propylene group, 1,2-vinylidene group, etc., among these, methylene group, 1,2-ethylene At least one selected from the group consisting of a group and a 1,2-vinylidene group is preferred, and a methylene group is particularly preferred because it is readily available and inexpensive.

From the viewpoint of improving the heat resistance of the cured product, the composition of the present invention preferably contains an acid anhydride curing agent represented by the general formula (3) among these acid anhydride curing agents. . Moreover, the acid anhydride type hardening | curing agent represented by General formula (2) and the acid anhydride type hardening | curing agent represented by General formula (3) can also be used together.
Below, the specific example of General formula (2) is shown.

  Among these, the following compounds are preferable.

  Below, the specific example of General formula (3) is shown.

  Among these, the following compounds are preferable.

In the composition of the present invention, the use of the acid anhydride curing agent described above provides the effect of lowering the viscosity and facilitating molding and processing.
Moreover, there is no restriction | limiting in particular in content of an acid anhydride type hardening | curing agent, The molar ratio of the acid anhydride group with respect to the epoxy group contained in the polyfunctional epoxy resin composition of this invention is 0.4-1.5. Preferably, it is 0.6 to 1.3, more preferably 0.7 to 1.2.

The acid anhydride curing agent may be used alone or in any combination and ratio, and acid anhydride curing agents outside the above ranges and other known epoxy resins may be used. You may use it in combination with a hardening | curing agent. Such epoxy resin curing agents include phenolic curing agents, ester curing agents, benzoxazine curing agents, primary and secondary amine curing agents, mercaptan curing agents, amide curing agents, and blocked isocyanate curing agents. Etc. As for the content in the case of using 2 or more types of acid anhydride curing agents, the total amount is preferably in the above-mentioned preferable range.

When the acid anhydride curing agent is used in combination with another epoxy resin curing agent, the total molar ratio of reaction sites of all curing agents to the epoxy group is preferably 0.4 to 1.5,
More preferably, it is 0.6 to 1.3. The content of the acid anhydride curing agent relative to the total amount of the curing agent is preferably 30% by weight or more, and more preferably 50% by weight or more.

<Curing accelerator>
The polyfunctional epoxy resin composition of the present invention may contain a curing accelerator. Curing accelerators include imidazole curing accelerators, tertiary amine curing accelerators, organic phosphine curing accelerators, phosphonium salt curing accelerators, tetraphenylboron salt curing accelerators, metal curing accelerators, organic Examples include acid dihydrazide and boron halide amine complex. Among these, an imidazole-based curing accelerator is preferable because a cured product having high activity for a curing reaction and high heat resistance can be obtained.

Specific examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-
Ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1- Cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-
Cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- ( 1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2 ′ -Ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine isocyanuric acid addition , 2-phenylimidazole isocyanuric acid adduct, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-phenyl-4,5-dihy Droxymethylimidazole, 2-phenyl-4-methyl-5hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1
, 2-a] imidazole compounds such as benzimidazole and 2-phenylimidazoline, and adducts of imidazole compounds and epoxy resins. Among these, since it can be easily dissolved and mixed in the composition and a highly uniform cured product can be obtained, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4 -Methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-
From the group consisting of 2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, and 1-cyanoethyl-2-phenylimidazole At least one selected is more preferable, and 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, or 1-cyanoethyl-2-ethyl-4-methylimidazole is particularly preferable.

Specific examples of the tertiary amine curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,
4,6, -tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo [5,
And tertiary amine compounds such as 4,0] -7-undecene and adducts of these tertiary amine compounds and epoxy resins.

The content of the imidazole curing accelerator and the amine curing accelerator contained in the polyfunctional epoxy resin composition of the present invention is such that the polyfunctional epoxy resin composition of the present invention can be sufficiently cured in a short time. A large amount is preferable. On the other hand, the storage stability of the polyfunctional epoxy resin composition of the present invention, the low coefficient of thermal expansion, and the effect of the curing accelerator on the cured product are preferably small. Specifically, it is preferably used in an amount of 0.1 part by weight or more based on 100 parts by weight of the epoxy resin contained in the polyfunctional epoxy resin composition of the present invention.
More preferably, it is used so as to be 2 parts by weight or more, and on the other hand, it is preferably used so as to be 20 parts by weight or less, and more preferably used so as to be 10 parts by weight or less.

Organic phosphine-based curing accelerators include triphenylphosphine, diphenyl (p-tolyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkylalkoxyphenyl) phosphine, tris (dialkylphenyl) phosphine , Tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkylarylphosphine, alkyl Organic phosphines such as diarylphosphine; complexes of these organic phosphines and organic borons; 1
, 4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4
Examples include quinones such as benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone, and compounds added with a compound such as diazophenylmethane. Phosphonium salt curing accelerators include phosphonium salts such as ethyltriphenylphosphonium salt, benzyltriphenylphosphonium salt, tetraphenylphosphonium salt, methyltributylphosphonium salt and counter anions such as chloride ion, bromide ion, and organic phosphate ion. Combinations: Complexes of these organic phosphonium salts and organic borons can be mentioned. Examples of the tetraphenylboron salt-based curing accelerator include a tetraphenylboron salt of 2-ethyl-4-methylimidazole, a tetraphenylboron salt of N-methylmorpholine, and the like.

The content of the organic phosphine-based curing accelerator, phosphonium salt-based curing accelerator, and tetraphenylboron salt-based curing accelerator contained in the polyfunctional epoxy resin composition of the present invention is the same as that of the polyfunctional epoxy resin composition of the present invention. Per 100 parts by weight of epoxy resin contained in
It is preferably used so as to be 1 part by weight or more, more preferably used so as to be 0.005 part by weight or more, and on the other hand, it is preferably used so as to be 20 parts by weight or less. More preferably, it is used so that it is less than 5 parts by weight.

Examples of the metal curing accelerator include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organometallic complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, and zinc (II) acetylacetonate. Organic zinc complexes such as iron (III) acetylacetonate, nickel (II)
And organic nickel complexes such as acetylacetonate and manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate. Among these, from the viewpoint of solvent solubility and curability of the polyfunctional epoxy resin composition of the present invention, cobalt (II) acetylacetonate, cobalt (III) acetylacetonate, zinc (II) acetylacetonate, naphthenic acid Zinc and iron (III) acetylacetonate are preferred, and cobalt (III) acetylacetonate and zinc naphthenate are particularly preferred.

The content of the metal-based curing accelerator contained in the polyfunctional epoxy resin composition of the present invention is preferably large in that it is easy to form a conductor layer having excellent peel strength on the surface of the low-roughness insulating layer. On the other hand, it is preferable that the polyfunctional epoxy resin composition of the present invention is small in terms of excellent storage stability and insulation. Therefore, the metal derived from the metal curing agent is preferably 500 ppm or less, more preferably 200 ppm or less, based on the total amount of the polyfunctional epoxy resin and the acid anhydride curing agent in the composition. And preferably 20 ppm or more.
More preferably, it is 0 ppm or more.

Also, “Review Epoxy Resin Volume 1” (1st Edition, Epoxy Resin Technology Association, 2003)
119-209 and "Review Epoxy Resin Recent Progress I" (First Edition, Epoxy Resin Technology Association, 2009), pages 43-84, curing agents and curing accelerators may be used.
The type and combination of curing agent and curing accelerator and the amount thereof are balanced with the content of the above-mentioned acid anhydride curing agent and the curing conditions, the shape of the cured product, the physical properties such as the adhesiveness and bending strength of the cured product, etc. Select according to your needs.

<Inorganic filler>
The polyfunctional epoxy resin composition of the present invention may contain an inorganic filler. When an inorganic filler is included, when the polyfunctional epoxy resin composition of the present invention is cured, the physical properties of the inorganic filler, such as low linear expansion coefficient, high thermal conductivity, flame retardancy, and conductivity, are obtained in the cured product. Can be granted. Since the polyfunctional epoxy resin of the present invention has a low viscosity, it is easy to maintain excellent processability even if the content of the inorganic filler is increased.

The kind of the inorganic filler may be selected according to desired physical properties. For example, when it is desired to obtain an insulating composition at low cost, it is preferable to use an insulating inorganic filler such as alumina, aluminum nitride, boron nitride, silicon nitride, silica, etc. Among these, a composition having particularly high thermal conductivity In the case where it is desired to obtain, alumina, aluminum nitride, boron nitride and the like are preferable. When it is desired to obtain a conductive composition, it is preferable to use an electrically conductive inorganic filler such as aluminum, silver, copper, carbon, silicon carbide, etc. Of these, when a composition excellent in workability is particularly desired. Silver is preferred.

In addition, the inorganic filler may be appropriately subjected to a surface treatment. Examples of the surface treatment include alkylation treatment, trimethylsilylation treatment, silicone treatment, treatment with a silane coupling agent, and the like, but are not particularly limited.
The shape and particle size of the inorganic filler are not particularly limited as long as the desired effects due to the inclusion of the inorganic filler are exhibited without significantly hindering the excellent physical properties of the polyfunctional epoxy resin composition of the present invention. However, regarding the shape of the inorganic filler, when it is desired to obtain a composition having excellent processability, an inorganic filler having a small surface area such as a sphere is fibrous, etc. in that the functions such as the thermal conductivity of the inorganic filler are easily exhibited. An inorganic filler having a large surface area is preferably an inorganic filler having an intermediate surface area such as a flat shape in that it is easy to balance the two.

The particle size of the inorganic filler is preferably small from the viewpoint that voids are not easily generated in a cured product obtained by curing the polyfunctional epoxy resin composition of the present invention. On the other hand, it is preferable that the inorganic filler is large in that it does not aggregate and is easily dispersed. Therefore, specifically, the particle size is preferably 0.05 μm or more, more preferably 0.1 μm or more, particularly preferably 0.5 μm or more, and on the other hand, 1000 μm or less. Preferably, it is 200 micrometers or less, It is especially preferable that it is 100 micrometers or less. The particle size can be measured by a method such as a laser diffraction scattering method or a sedimentation method.

The content of the inorganic filler in the case where the polyfunctional epoxy resin composition of the present invention contains an inorganic filler is preferably large in that the effect of using the inorganic filler is easily exhibited.
On the other hand, it is preferable that the polyfunctional epoxy resin composition of the present invention is small in that it tends to be excellent in processability.
Therefore, specifically, the content of the inorganic filler is preferably 10% by weight or more, more preferably 30% by weight or more, based on the content of all nonvolatile components in the composition.
The content is more preferably 0% by weight or more, and particularly preferably 70% by weight or more.
On the other hand, it is preferably 95% by weight or less, more preferably 92% by weight or less, and further preferably 90% by weight or less. An inorganic filler may be used only by 1 type, or may use 2 or more types by arbitrary combinations and a ratio. As for the content in the case of using two or more kinds of inorganic fillers, the total amount is preferably in the above-mentioned preferable range.

<Solvent>
The polyfunctional epoxy resin composition of the present invention may contain a solvent for adjusting the viscosity at the time of processing and handling properties when curing. As the solvent, the solvent used when producing the polyfunctional epoxy resin of the present invention may be used. Examples of the solvent contained in the polyfunctional epoxy resin composition of the present invention include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate; ethers such as ethylene glycol monomethyl ether Amides such as N, N-dimethylformamide and N, N-dimethylacetamide; alcohols such as methanol, ethanol and isopropanol; alkanes such as hexane and cyclohexane; aromatics such as toluene and xylene; These solvents may be used alone or in combination of two or more in any ratio.

The amount of the solvent used is preferably not used or small because voids are easily formed in the cured product due to residual solvent. In addition, since it is preferable that there is much quantity of a solvent at the point that the crack accompanying the increase in viscosity of a composition does not generate | occur | produce, it is good to adjust suitably according to the viscosity to obtain | require.

<Other additives>
The polyfunctional epoxy resin composition of the present invention may further contain an additive in addition to those described above. Examples of other additives include a silane coupling agent and a titanate coupling agent used for improving the adhesion between the polyfunctional epoxy resin composition of the present invention and a cured product obtained by curing the composition and a substrate. Coupling agents such as: UV inhibitors, antioxidants, plasticizers used to improve storage stability; fluxes for removing oxide film on solder; flame retardants;
Colorants; dispersants; emulsifiers; low elasticity agents; diluents; antifoaming agents; ion trapping agents and the like.

As the silane coupling agent, γ-glycidoxypropyltrimethoxysilane, γ-
Epoxysilanes such as glycidoxypropyltriethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane Aminosilanes such as N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane; mercaptosilanes such as 3-mercaptopropyltrimethoxysilane; -Vinyl silanes such as styryltrimethoxysilane, vinyltrichlorosilane, vinyltris (8-methoxyethoxy) silane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane; Amino-based, and the like silanes polymer type vinyl system.

Titanate coupling agents include isopropyl triisostearoyl titanate,
Isopropyltri (N-aminoethyl-aminoethyl) titanate, diisopropyl bis (dioctyl phosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxy) Methyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (
And dioctyl pyrophosphate) ethylene titanate.

It is preferable that the content of the coupling agent when the polyfunctional epoxy resin composition of the present invention contains a coupling agent is large in that it is easy to obtain an adhesive effect due to the coupling agent blending. On the other hand, it is preferable that the coupling agent is small in that it is difficult to bleed out. Therefore, specifically, the content of the coupling agent with respect to the total amount of the polyfunctional epoxy resin and the acid anhydride curing agent in the polyfunctional epoxy resin composition of the present invention is 0.1% by weight or more and 2.0%. It is preferable that it is below wt%. A coupling agent may be used only by 1 type, or may be used 2 or more types by arbitrary combinations and ratios. As for the content in the case of using 2 or more types of coupling agents, the total amount is preferably within the above-mentioned preferable range.

<Characteristics of polyfunctional epoxy resin composition>
The polyfunctional epoxy resin composition of the present invention preferably has fluidity at a temperature lower than the curing temperature, from the viewpoint of the efficiency of work during molding and safety. The minimum temperature having fluidity is preferably 100 ° C. or less, more preferably 80 ° C. or less, and 6
A temperature of 0 ° C. or lower is particularly preferable. Whether the composition has fluidity can be determined by, for example, stirring the composition to create irregularities on the surface and then leaving it at a predetermined temperature to return the surface to a smooth surface.

In addition, the polyfunctional epoxy resin composition of the present invention is easy to mold and process.
The shear viscosity at 0 ° C. is preferably 100 Pa · sec or less, more preferably 50 Pa · sec or less, further preferably 30 Pa · sec or less, particularly preferably 20 Pa · sec or less, Most preferably, it is 10 Pa · sec or less. In addition, if the viscosity is too low, the inorganic filler in the composition of the present invention may settle and cause separation, so the lower limit of the viscosity is usually 0.3 Pa · second or more, preferably 1 Pa · second or more. It is.

<Hardened product>
The cured product of the present invention can be obtained by curing the polyfunctional epoxy resin composition of the present invention.
The curing method and conditions are not particularly limited as long as the composition of the present invention can be cured, but thermosetting is preferable because it is easy to mold. When thermosetting the composition of the present invention,
There is no particular limitation on the conditions, but the curing temperature is preferably higher from the viewpoint of sufficiently curing the cured product and exhibiting the original performance, from the viewpoint of improving productivity and suppressing thermal decomposition of the cured product. Is preferably lower. Specifically, the curing temperature is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, 250 ° C. or lower, more preferably 220 ° C. or lower. The curing time is preferably longer from the viewpoint of suppressing the occurrence of cracks due to rapid curing, and shorter from the viewpoint of improving productivity. Specifically, the curing time is preferably 30 minutes or more.
More than the time is more preferable, 8 hours or less is preferable, and 6 hours or less is more preferable. This thermal curing may be carried out in multiple stages, in which case it is preferred that the curing temperature and curing time of at least one stage fall within the above range.

The cured product of the present invention has a high glass transition temperature and excellent heat resistance. The glass transition temperature of the cured product of the present invention measured by dynamic viscoelasticity is, for example, that the polyfunctional epoxy resin composition of the present invention is heated at 120 ° C. for 1 hour, 150 ° C. for 1 hour, and 220 ° C. for 2 hours. When cured, preferably 190 ° C. or higher, more preferably 210 ° C. or higher, more preferably 225 ° C. or higher,
Especially preferably, it is 235 degreeC or more. The upper limit of the glass transition temperature is usually 350 ° C.

Moreover, since the polyfunctional epoxy resin in this hardened | cured material has biphenyl frame | skeleton, the hardened | cured material of this invention is excellent in thermal conductivity. The thermal conductivity of the cured product of the present invention is preferably 0.3 W / m · K or more, more preferably 0.35 W / m · K or more when no inorganic filler is contained. More preferably, it is 4 W / m · K or more.
When the cured product of the present invention is used by being bonded to other members such as metal, the cured product of the present invention and the surrounding members are used from the viewpoint of preventing peeling and cracks by reducing the difference in thermal expansion with the surrounding members. It is preferable that the linear expansion coefficient is close. For example, when using copper or aluminum as an adhesive member,
The average linear expansion coefficient at 100 ° C. is preferably 80 ppm / K or less, and 60 ppm
/ K or less, more preferably 40 ppm / K or less,
It is particularly preferably 30 ppm / K or less. Moreover, as a minimum, it is preferable that it is 5 ppm / K or more, and it is more preferable that it is 10 ppm / K or more. Also, 170 ~
The average linear expansion coefficient at 200 ° C. is preferably 100 ppm / K or less, and 80 pp
m / K or less is more preferable, 60 ppm / K or less is further preferable, and 40 ppm / K or less is particularly preferable. Moreover, as a minimum, it is preferable that it is 5 ppm / K or more, and it is more preferable that it is 10 ppm / K or more.

Further, the cured product of the present invention has a storage elastic modulus at 25 ° C. of 1.0 × 10 ⁷ Pa or more and 1.0.
× 10 ¹¹ Pa or less is preferable, and 1.0 × 10 ⁸ Pa to 5.0 × 10 ¹⁰ P
More preferably, it is a or less. When the storage elastic modulus at 25 ° C. is larger than 1.0 × 10 ¹¹ Pa, cracks are likely to occur due to residual stress due to curing shrinkage. 1.0x
When it is less than 10 ⁷ Pa, the mechanical strength of the cured product is not sufficient.

<Application>
The polyfunctional epoxy resin composition of the present invention contains a polyfunctional epoxy resin in the above range and an acid anhydride curing agent, so that the viscosity can be kept low even when a large amount of inorganic filler is contained. Therefore, it has sufficient processability to be applied to processes such as coating, mixing and film forming, and can be suitably used particularly for potting sealing materials for semiconductor devices.

And the hardened | cured material which hardened this composition is excellent in heat resistance. Therefore, adhesives, paints,
It can be applied as a material in various fields such as civil engineering materials and insulating materials in the electric / electronic field. In particular, it is useful as an insulating casting, laminate material, sealing material, etc. in the electric / electronic field. Examples of uses of the polyfunctional epoxy resin composition and the cured product thereof according to the present invention include multilayer printed wiring boards, film adhesives, liquid adhesives, semiconductor sealing materials, underfill materials, and 3D-LSI interchip fills. Insulating sheet, prepreg, heat dissipation substrate and the like.

Hereinafter, the present invention will be described in more detail by experimental examples (Examples, Comparative Examples).
Unless it exceeds the gist, it is not limited by the following examples. In addition, the values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the value of the upper limit or the lower limit. It may be a range defined by a combination of values of the following examples or values of the examples.
Hereinafter, measurement methods, materials, and reagents used in Examples and Comparative Examples will be described.

<Measurement method>
Various measurements in Examples and Comparative Examples were performed as follows.
(Epoxy equivalent)
Epoxy equivalent was carried out according to JIS K7236: 2001. A precisely weighed sample was dissolved in chloroform, and acetic acid and tetraethylammonium bromide acetic acid solution were added.
It determined by titrating with mol / L perchloric acid acetic acid standard solution. The end point was determined using a crystal violet indicator.

(1H-NMR analysis)
1H-NMR analysis of the synthesized epoxy resin was performed under the following conditions.
Equipment: AVANCE400, 400MHz manufactured by BRUKER
Solvent: 0.03 vol% tetramethylsilane-containing deuterated chloroform Accumulated number: 16 times In the data described later, the δ value in 1H-NMR (400 MHz, CDCl3) is represented.

(Initial viscosity)
The change over time of the shear viscosity at 60 ° C. of the polyfunctional epoxy resin composition was measured under the conditions described below, and the value when the viscosity was the lowest during the measurement was taken as the initial viscosity.
Apparatus: Rheometer (MCR302, manufactured by Anton Paar)
Temperature control system: Peltier temperature control device (P-PTD200)
And food type Peltier temperature control system (H-PTD200)
Plate: 20mmφ parallel plate Measurement gap: 0.5mm
Shear rate: 7.5 s ^-1

(Glass-transition temperature)
As a measurement sample, a cured product having a thickness of about 1 mm was cut into a strip shape having a length of 30 mm, a width of 5 mm, and a thickness of about 1 mm, and measurement was performed under the following conditions. The temperature at which the loss elastic modulus E ″ in the dynamic viscoelasticity measurement was maximized was defined as the glass transition temperature.
Apparatus: DII-6100 manufactured by SII Nano Technology
Measurement mode: Pull mode Measurement temperature: -70 ° C to 235 ° C
Temperature increase rate: 4 ° C / min
Frequency: 1Hz
Hereinafter, materials and reagents used in Examples and Comparative Examples will be described. The synthesis method is not limited to the described method, and any known method can be applied.

(Synthesis Example 1)
A polyfunctional epoxy resin A represented by the formula (A) was synthesized by the method described in JP-A No. 63-142019. This polyfunctional epoxy resin A was a bowl-like liquid at room temperature, and the epoxy equivalent was 115 g / eq. The 1H-NMR data was as follows.
2.58-2.64 (2H, m, C-glycidyl terminus), 2.77-2.82 (2H +
2H, m, C-glycidyl terminal, O-glycidyl terminal), 2.87-2.96 (2H + 2
H, m, C—C H2 —CH—, O-glycidyl terminus), 2.97-3.06 (2H, m,
C-CH2-C H -) , 3.25 (2H, m, C-CH2-C H -), 3.39 (2H,
m, O-CH2-C H -), 3.95-4.05 (2H, m, O-C H2 -CH), 4.
27-4.34 (2H, m, O—C H2 —CH), 6.88-6.92 (2H, m, Ar
) 7.37-7.41 (4H, m, Ar)

(Synthesis Example 2)
A polyfunctional epoxy resin B represented by the formula (B) was synthesized by the same method as in Synthesis Example 1. This polyfunctional epoxy resin B was a bowl-like liquid at room temperature, and the epoxy equivalent was 130 g / eq.
The 1H-NMR data was as follows.
1.63 (6H, s, Me), 2.52-2.56 (2H, m, C-glycidyl end)
, 2.72-2.83 (2H + 2H + 2H , m, C- glycidyl terminal, O- glycidyl terminal, C-C H2 -CH), 2.86-2.94 (4H, m, O- glycidyl terminal, C- C
H2 -CH), 3.13-3.20 (2H, m, C-CH2-C H -), 3.32-3.
38 (2H, m, O- CH2-C H -), 3.90-3.98 (2H, m, O-C H2 -
CH -), 4.19-4.26 (2H, m, O-C H2 -CH -), 6.72-6.76
(2H, m, Ar), 7.00-7.08 (4H, m, Ar)

  Other reagents used in Examples and Comparative Examples are as follows.

(Licacid HNA-100)
Ricacid HNA-100 is manufactured by Shin Nippon Rika Co., Ltd., methylbicyclo [2,2,1] heptane-2,3-dicarboxylic anhydride: Formula (C) and bicyclo [2,2,1] heptane-2
, 3-dicarboxylic acid anhydride: An acid anhydride mixed with the formula (D).

(Licacid MH-700)
Ricacid MH-700 is manufactured by Shin Nippon Chemical Co., Ltd., and is an acid anhydride in which 4-methylhexahydrophthalic anhydride: formula (E) and hexahydrophthalic anhydride: formula (F) are mixed in a ratio of 7/3. .

(YH307)
YH307 is manufactured by Mitsubishi Chemical Corporation, and 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydrophthalic anhydride: Formula (G) and 1-isopropyl -4-Methyl-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid anhydride: An acid anhydride mixed with the formula (H).

(C11Z-CN)
C11Z-CN is manufactured by Shikoku Kasei Co., Ltd. (chemical name: 1-cyanoethyl-2-undecylimidazole), and the structural formula is as shown in the following formula (I).

(PSM-6200)
PSM-6200 is a phenol novolac manufactured by Gunei Chemical Industry Co., Ltd.
(DDM)
DDM is manufactured by Tokyo Chemical Industry Co., Ltd. (chemical name: 4,4′-diaminodiphenylmethane),
The structural formula is as shown in the following formula (J).

(HL-3100)
HL-3100 is a true spherical silica filler manufactured by Tatsumori.

<Example 1>
Polyfunctional epoxy resin A, acid anhydride curing agent HNA-100, and curing accelerator C11Z-CN are mixed at 60 ° C. in a weight ratio shown in Table 1 until uniform, and further, silica filler HL— 3100 was added and stirred and mixed at 60 ° C. for 10 minutes to obtain a polyfunctional epoxy resin composition of Example 1 (hereinafter abbreviated as “composition”).
The composition was cured by heating at 120 ° C. for 1 hour, 150 ° C. for 1 hour, and 220 ° C. for 2 hours to obtain a cured product having a thickness of about 1 mm.

<Example 2>
The composition of Example 2 was obtained by producing under the same conditions as in Example 1 except that the materials were mixed at the weight ratio shown in Table 1.
The composition was cured by heating at 120 ° C. for 2 hours and at 150 ° C. for 4 hours to obtain a cured product having a thickness of about 1 mm.

<Comparative Example 1>
Attempts were made to mix the polyfunctional epoxy resin A, the phenol curing agent PSM-6200, and the curing accelerator C11Z-CN at 60 ° C. at a weight ratio shown in Table 1, but the phenol curing agent did not melt at 60 ° C. and was uniform. Could not be obtained. By heating and mixing this liquid up to 80 ° C., the phenol curing agent was dissolved and a uniform liquid could be obtained, but the composition obtained by adding the silica filler HL-3100 to this liquid and mixing uniformly, The viscosity was very high and did not level at 60 ° C.

<Comparative Example 2>
Attempts were made to mix the polyfunctional epoxy resin A and the amine curing agent DDM at 60 ° C. at the ratio shown in Table 1. However, at 60 ° C., the amine curing agent did not melt and a uniform liquid could not be obtained.
By heating and mixing this liquid to 90 ° C., the amine curing agent was dissolved and a uniform liquid could be obtained. However, at 90 ° C., the viscosity increased during mixing. Stability during preparation was poor.

<Comparative Example 3>
A composition of Comparative Example 3 was obtained by producing under the same conditions as in Example 1 except that the materials were mixed at the weight ratio shown in Table 1.
The composition was cured by heating at 120 ° C. for 2 hours and at 150 ° C. for 4 hours to obtain a cured product having a thickness of about 1 mm.

<Comparative example 4>
The composition of Comparative Example 4 was obtained by producing under the same conditions as in Example 1 except that the materials were mixed at the weight ratios shown in Table 1.
The composition was cured by heating at 120 ° C. for 2 hours and at 150 ° C. for 4 hours to obtain a cured product having a thickness of about 1 mm.
Table 1 shows the mixing ratio of each component of the polyfunctional epoxy compositions of the above Examples and Comparative Examples, and the physical property measurement results of the compositions and cured products.

The polyfunctional epoxy resin composition of the present invention has low viscosity and is easy to mold and process, and has high heat resistance when cured to give a cured product. It can be used as materials in various fields such as materials.

Claims (4)

A polyfunctional epoxy resin composition containing a polyfunctional epoxy resin and an acid anhydride curing agent,
The polyfunctional epoxy resin is
The following general formula (1)

(In general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group or a halogen atom. M and n each independently represents an integer of 0 to 3.)
It is represented by
The acid anhydride curing agent is
The following general formula (2)

(In the general formula (2), R ^{3 to} R ⁶ each independently represent a hydrogen atom or a methyl group. X represents a single bond or a double bond.)
Or
The following general formula (3)

In (formula ^(3), R 3 ~R ⁶ have the same meanings as in formula (2) .R ⁷ is C 1 -C
Represents a divalent hydrocarbon group which may be branched to 3; X represents a single bond or a double bond. )
The polyfunctional epoxy resin composition characterized by being represented by any one of these. In addition, it contains an inorganic filler,
The polyfunctional epoxy resin composition according to claim 1, wherein the content of the inorganic filler is 50% by weight or more based on the content of all nonvolatile components of the polyfunctional epoxy resin composition. Furthermore, the polyfunctional epoxy resin composition of Claim 1 or Claim 2 containing an imidazole series hardening accelerator. Hardened | cured material formed by hardening | curing the polyfunctional epoxy composition as described in any one of Claims 1-3.