JP2016084467A - Epoxy resin, epoxy resin composition, cured product, and laminate for electric/electronic circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin excellent in high heat resistance, low hygroscopicity, low linear expansion, flame retardancy, film forming property (coating property), elongation and the like, an epoxy resin composition comprising the epoxy resin and a curing agent, and a cured product thereof, and a laminate for an electric/electronic circuit comprising the epoxy resin composition.SOLUTION: An epoxy resin is formed by a reaction of fluorene bisphenol having a structure illustrated by formula (7), a diol comprising a bisphenol, and a diepoxy compound. The epoxy resin has a weight average molecular weight of 1,000-200,000 and has an epoxy group at least one terminal.SELECTED DRAWING: None

Description

  The present invention relates to an epoxy resin excellent in low hygroscopicity. The present invention also relates to an epoxy resin composition containing the epoxy resin and a curing agent, a cured product thereof, and a laminate for an electric / electronic circuit comprising the epoxy resin composition.

  Epoxy resins are excellent in heat resistance, adhesiveness, water resistance, mechanical strength, and electrical properties, so they can be used in various fields such as adhesives, paints, civil engineering and building materials, and insulating materials for electrical and electronic parts. It is used. In particular, in the electric / electronic field, it is widely used in insulating casting, laminated materials, sealing materials and the like. In recent years, multilayer circuit boards used in electrical and electronic equipment have been reduced in size, weight and functionality, and further multilayered, denser, thinner, lighter and more reliable and molded. Improvements in workability are required.

  Low hygroscopicity is an important performance required for epoxy resins used as materials for electrical and electronic parts such as laminates for electrical and electronic circuits. If the water absorption rate is high, moisture evaporates and expands in a heating process such as reflow, causing cracks and peeling. In addition, it is necessary to have a low hygroscopic property from the viewpoint of suppressing a decrease in insulation reliability due to ion migration and an increase in dielectric loss due to polarization of water molecules.

  Recently, attempts have been made to improve properties by introducing various chemical structures into epoxy resins. Among them, an example in which a chemical structure having a large molecular weight is introduced and the secondary hydroxyl group concentration is reduced for the purpose of improving low hygroscopicity is disclosed. As an example of such an epoxy resin, Patent Document 1 discloses an epoxy resin into which a fluorene skeleton is introduced.

JP 2003-252951 A

  Although the epoxy resin having a fluorene skeleton described in the patent document is superior in heat resistance as compared with a conventional epoxy resin, low hygroscopicity is not sufficient. This invention solves the said subject, and also makes it a subject to provide the epoxy resin excellent in balance, such as high heat resistance, low linear expansion property, a flame retardance, film-forming property, and an elongation property. .

  As a result of intensive studies to solve the above problems, the present inventors have found that an epoxy resin having a specific chemical structure is excellent in low moisture absorption. That is, the gist of the present invention resides in the following [1] to [14].

[1] An epoxy resin represented by the following formula (1) and having a weight average molecular weight of 1,000 to 200,000.

(In the above formula (1), A necessarily includes the chemical structure represented by the above formula (2), R and R ′ may be different from each other, and are a hydrogen atom or a group represented by the above formula (3). And at least one of them is a group represented by the above formula (3), n is an average value of the number of repetitions, and is 1 or more and 500 or less, in the above formula (2), R ^{1 to} R ¹⁰ May be the same as or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen element, and any two substitutions adjacent on the benzene ring among R ^{1 to} R ⁸ The groups may be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1 and k2 may be the same or different from each other, and represent an integer of 0 to 4. in the above formula (2), a ¹ and a ² may be the being the same or different, Arbitrary group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, aryl group having 6 to 12 carbon atoms, alkenyl group having 1 to 12 carbon atoms, and alkynyl group having 1 to 12 carbon atoms as a substituent An aromatic ring which may have a selected group, X ¹ and X ² may be the same or different from each other; a direct bond; a divalent hydrocarbon group having 1 to 13 carbon atoms; O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.

[2] The epoxy resin according to [1], wherein the chemical structure represented by the formula (2) is included in the formula (1) in an amount of 1 to 99 mol% based on the total number of moles of A.

[3] In the formula (1), A includes a chemical structure represented by the following formula (4), and the chemical structure represented by the formula (4) is 1 to 99 mol with respect to the total number of moles of A. % Epoxy resin according to [1] or [2].

(In the above formula (4), X ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, —SO ₂ —, —C (CF ₃ ) ₂ — and — A group selected from CO-, R ^{11 to} R ^1
8 may be different from each other and is a group selected from a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, or a halogen element. )

[4] Obtained by reacting a bifunctional epoxy resin represented by the following formula (5) with a bisphenol compound represented by the following formula (6), the weight average molecular weight is 1,000 to 200,000. An epoxy resin.

(In the above formula (5) or (6), A ′ necessarily includes the chemical structure represented by the above formula (2) ′, m is the average number of repetitions, and is 0 or more and 6 or less. In formula (2) ′, R ′ ^{1 to} R ′ ¹⁰ may be the same as or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a halogen element, and R ′ ^{1 to} R ′. Two arbitrary substituents adjacent to each other on the benzene ring in ' ⁸ may be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1' and k2 'are the same as each other. Or may be different, and represents an integer of 0 to 4. Furthermore, in the above formula (2), A ′ ¹ and A ′ ² may be the same or different from each other, and carbon as a substituent C1-C12 alkyl group, C1-C12 alkoxy group, C6-C12 aryl group, C1-C12 alkene An aromatic ring optionally having a group selected from a nyl group and an alkynyl group having 1 to 12 carbon atoms, and X ′ ¹ and X ′ ² may be the same or different from each other, and bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, -O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.

[5] In the formula (5) and / or (6), the chemical structure represented by the formula (2) ′ is 1 to 99 mol% with respect to the total number of moles of A ′. [4] The epoxy resin described in 1.

[6] In the formulas (5) and (6), A ′ includes a chemical structure represented by the following formula (4) ′, and the chemical structure represented by the formula (4) ′ is a mole of A ′ as a whole. The epoxy resin according to [4] or [5], which is contained in an amount of 1 to 99 mol% based on the number.

(In the above formula (4) ′, X ′ ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, —SO ₂ —, —C (CF ₃ ) ₂ —. And R ′ ^{11 to} R ′ ¹⁸ may be different from each other and are a group selected from a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, or a halogen element.)

[7] The epoxy resin according to any one of [1] to [6], wherein the epoxy equivalent is 500 g / equivalent or more and 100,000 g / equivalent or less.

[8] The chemical structure represented by the formula (2) and the chemical structure represented by (2) ′ are the following formula (7), according to any one of [1] to [7] Epoxy resin.

[9] An epoxy resin composition comprising the epoxy resin according to any one of [1] to [8] and a curing agent.

[10] The epoxy resin composition according to [9], including 0.1 to 100 parts by weight of the curing agent with respect to 100 parts by weight of the epoxy resin.

[11] The epoxy resin composition according to [9] or [10], further including another epoxy resin and including 1 to 99% by weight of the other epoxy resin in the total epoxy resin component as a solid content.

[12] Any one of [9] to [11], further including another epoxy resin and 0.1 to 100 parts by weight of the curing agent with respect to 100 parts by weight of the total epoxy resin component as a solid content. The epoxy resin composition described in 1.

[13] A cured product obtained by curing the epoxy resin composition according to any one of [9] to [12].

[14] A laminate for an electric / electronic circuit comprising the epoxy resin composition according to any one of [9] to [12].

According to the present invention, it is possible to provide an epoxy resin and an epoxy resin composition that are excellent in low moisture absorption and excellent in balance of high heat resistance, low linear expansion property, flame retardancy, film-forming property, stretchability, and the like. Can do. For this reason, the epoxy resin and epoxy resin composition of the present invention can be applied to various fields such as adhesives, paints, building materials for civil engineering, insulating materials for electric / electronic parts, etc., especially in the electric / electronic field. Useful as casting, laminating material, sealing material and the like. The epoxy resin of the present invention and the epoxy resin composition containing the same are used for multilayer printed wiring boards, laminates for electric / electronic circuits such as capacitors, adhesives such as film adhesives and liquid adhesives, semiconductor sealing materials, It can be suitably used for fill materials, 3D-LSI interchip fills, insulating sheets, prepregs, heat dissipation substrates, and the like.

  Embodiments of the present invention will be described in detail below. However, the following description is an example of the embodiments of the present invention, and the present invention is not limited to the following descriptions unless it exceeds the gist. It is not something. In addition, when using the expression “to” in the present specification, it is used as an expression including numerical values or physical property values before and after the expression.

〔Epoxy resin〕
The epoxy resin of the present invention is represented by the following formula (1) and has a weight average molecular weight of 1,000 to 200,000.

(In the above formula (1), A necessarily includes the chemical structure represented by the above formula (2), R and R ′ may be different from each other, and are a hydrogen atom or a group represented by the above formula (3). And at least one of them is a group represented by the above formula (3), n is an average value of the number of repetitions and is from 1 to 500. In the above formula (2), R ^{1 to} R ¹⁰ are The two substituents which may be the same or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a halogen element, and adjacent to each other in the benzene ring among R ^{1 to} R ⁸ are May be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1 and k2 may be the same as or different from each other, and each represents an integer of 0 to 4. (2), a ¹ and a ² may be the being the same or different, location The group is arbitrarily selected from an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 1 to 12 carbon atoms, and an alkynyl group having 1 to 12 carbon atoms. X ¹ and X ² may be the same or different from each other, and may be a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.

  The epoxy resin of the present invention has features such as excellent heat resistance, low linear expansion coefficient, low water absorption, and excellent flame retardancy. This is because heat resistance and low linear expansion are expressed by the rigidity of the fluorene skeleton in the following formula (2), and the molecular weight per unit unit is larger than that of a normal epoxy resin. It is presumed that the ratio of the secondary hydroxyl group to the entire molecular structure becomes relatively low, and low hygroscopicity is exhibited. Moreover, since the epoxy resin of this invention has many aromatic rings in addition to the fluorene skeleton which is a polycyclic aromatic, it is estimated that the carbonization rate at the time of combustion is high and excellent flame retardancy is obtained.

<Chemical structure>
In the formula (1), A necessarily includes the chemical structure represented by the formula (2). In said formula (2), R < ¹ > -R < ⁸ > may mutually be same or different, and is a hydrogen atom, a C1-C10 hydrocarbon group, or a halogen element, among R < ¹ > -R < ⁸ >. Two arbitrary substituents adjacent on the benzene ring may be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms. R ^{1 to} R ⁸ are preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a bromine atom, or a fluorine atom, and more preferably a hydrogen atom, a methyl group, or a tert-butyl group. When any two substituents adjacent to each other on the benzene ring among R ^{1 to} R ⁸ are bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, the cyclic structure includes an aromatic ring. For example, a benzene ring (4 carbon atoms), a naphthalene ring (8 carbon atoms), a cyclohexene ring (4 carbon atoms) and the like can be mentioned.

R ⁹ and R ¹⁰ in the formula (2) may be the same or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen element, preferably a hydrogen atom or carbon number 1 -4 alkyl group, bromine atom and fluorine atom, more preferably hydrogen atom, methyl group and tertiary butyl group. Further, when k1 or k2 is 2 or more, R ⁹ or R ¹⁰ may be different or the same in the same ring. In addition, the bonding position (substitution position) of R ⁹ or R ^{10 with} respect to the benzene ring constituting the fluorene skeleton is not particularly limited. In addition, k1 and k2 show the integer of 0-4, and may be same or different, Preferably it is 0 or 1, Especially preferably, it is 0.

A ¹ and A ² in the formula (2) are each independently a substituent having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or 2 carbon atoms. It is an aromatic ring which may have a group arbitrarily selected from -12 alkenyl groups and C2-C12 alkynyl groups.

The aromatic ring of A ¹ and A ^2, for example, a benzene ring, a naphthalene ring, and an aromatic ring having 6 to 14 carbon atoms such as anthracene ring. Among these, a benzene ring is preferable as the aromatic ring of A ¹ and A ² from the viewpoint of ease of synthesis and cost.

Here, there are the following as an alkyl group having 1 to 12 carbon atoms in the aromatic ring substituents A ¹ and A ² in the formula (2). For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, cyclopentyl group, n-hexyl group, isohexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, methylcyclohexyl group, n-octyl group, cyclooctyl group, n-nonyl group, 3,3,5-trimethylcyclohexyl group, n- Decyl group, cyclodecyl group, n-undecyl group, n-dodecyl group, cyclododecyl group, benzyl group, methylbenzyl group, dimethylbenzyl group, trimethylbenzyl group, naphthylmethyl group, phenethyl group, 2-phenylisopropyl group, etc. . Among these, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group is preferable.

Also, there are the following as an alkoxy group having 1 to 12 carbons in the aromatic ring substituents A ¹ and A ² in the formula (2). For example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, n-pentoxy group, isopentoxy group, neopentoxy group, tert-pentoxy group, cyclopent Toxyl group, n-hexyloxy group, isohexyloxy group, cyclohexyloxy group, n-heptoxy group, cycloheptoxy group, methylcyclohexyloxy group, n-octyloxy group, cyclooctyloxy group, n-nonyloxy group, 3,3,5-trimethyl Cyclohexyloxy group, n-decyloxy group, cyclodecyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclododecyloxy group, benzyloxy group, methylbenzyloxy group, dimethyl benzyloxy group, trimethylbenzyloxy group, naphthylmethoxy Group, Enechirokishi group, 2-phenyl-iso-propoxy group. Among these, C1-C4 alkoxy groups, such as a methoxy group, an ethoxy group, n-propoxy group, an isopropoxy group, n-butoxy group, are preferable.

Examples of the aryl group having 6 to 12 carbon atoms in the substituent of the aromatic ring of A ¹ and A ^{2 in} the formula (2) include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, and ethyl. Examples thereof include a phenyl group, a styryl group, a xylyl group, an n-propylphenyl group, an isopropylphenyl group, a mesityl group, an ethynylphenyl group, a naphthyl group, and a vinylnaphthyl group.

The alkenyl group having 2 to 12 carbon atoms in the substituents of the aromatic ring of A ¹ and A ² in the formula (2) include the following. For example, vinyl group, 1-propenyl group, 2-propenyl group, 1-methylvinyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1,3-butadienyl group, cyclohexenyl group, cyclohexadienyl Groups, cinnamyl groups, naphthyl vinyl groups and the like. Among these, 2 to 4 carbon atoms such as vinyl group, 1-propenyl group, 2-propenyl group, 1-methylvinyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1,3-butadienyl group, etc. Are preferred.

Furthermore, there are the following as an alkynyl group having 2 to 12 carbon atoms in the aromatic ring substituents A ¹ and A ² in the formula (2). Examples include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1,3-butanedienyl group, phenylethynyl group, naphthylethynyl group and the like. Among these, alkynyl groups having 2 to 4 carbon atoms such as ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1,3-butanedienyl group and the like are preferable.

A ¹ and A ² in the formula (2) are preferably an unsubstituted aromatic ring or an aromatic ring having a C 1-4 alkyl group as a substituent, and are particularly preferable from the viewpoint of ease of synthesis and cost. Is an unsubstituted aromatic ring.

X ¹ and X ² in the formula (2) may be the same or different from each other, and are a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, A divalent linking group selected from —SO ₂ — and —CO—.

Here, examples of the divalent hydrocarbon group having 1 to 13 carbon atoms of X ¹ and X ² in the formula (2) include —CH ₂ —, —CH (CH ₃ ) —, —C (CH _3). ) ₂ —, —C (CF ₃ ) ₂ —, —CHPh— (in the present invention, Ph is a phenyl group), —C (CH _{3
) Ph -, - CPh 2 -} , 9,9- fluorenylene group, 1,1-cyclopropylene group, 1
, 1-cyclobutylene group, 1,1-cyclopentylene group, 1,1-cyclohexylene group, 3,3,5-trimethyl-1,1-cyclohexylene group, 1,1-cyclododecylene group, 1,2 -Ethylene group, 1,2-cyclopropylene group, 1,2-cyclobutylene group, 1,2-cyclopentylene group, 1,2-cyclohexylene group, 1,2-phenylene group, 1,3-
Propylene group, 1,3-cyclobutylene group, 1,3-cyclopentylene group, 1,3-cyclohexylene group, 1,3-phenylene group, 1,4-butylene group, 1,4-cyclohexylene group, Examples include 1,4-phenylene group.

Among these linking groups of X ¹ and X ² in the above formula (2), a divalent group having 1 to 3 carbon atoms such as —CH ₂ —, —CH (CH ₃ ) —, —C (CH ₃ ) ₂ — and the like. Are preferred, and —O— is particularly preferred from the viewpoint of ease of synthesis and cost. If too many atoms are involved in the connection between the aromatic ring adjacent to the fluorene skeleton and A ¹ and A ² , the rigidity of the skeleton as a whole of the epoxy resin is lowered, the glass transition point is lowered, and the heat resistance may be lowered. There is sex.

  In the formula (1), R and R ′ are a hydrogen atom or a group (epoxy group) represented by the formula (3). That is, in the formula (1), R and R ′ represent terminal structures, and both ends may be the epoxy group of the formula (3), and one end may be a hydrogen atom. However, since the formula (1) is an epoxy resin, at least one of the terminals of the formula (1) includes an epoxy group. The epoxy resin of the present invention is usually a mixture of molecules having these ends or molecules having different repeating numbers n described below.

  In said Formula (1), n is a repeating number and is an average value. The range of the value is 1 or more from the viewpoint of film formability and stretchability, and is 500 or less from the viewpoint of the handleability of the resin. From the viewpoint of further improving the film-forming property and elongation, it is preferably 5 or more, more preferably 10 or more. On the other hand, from the viewpoint of further improving the handleability of the resin, preferably 200 or less. More preferably, it is 100 or less. The n number can be calculated from the number average molecular weight Mn obtained by the gel permeation chromatography method (GPC method). Specific examples of the GPC method for determining the number average molecular weight will be described in the examples below.

  In the formula (1), A includes at least the chemical structure represented by the formula (2), from the viewpoint of improving the balance of heat resistance, low hygroscopicity, low linear expansion, flame retardancy, and the like. The ratio of the chemical structure represented by the formula (2) in A is preferably 1 to 99 mol% with respect to the total number of moles of A. From the viewpoint of improving these effects, the proportion of the chemical structure represented by formula (2) in A is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol%. On the other hand, from the viewpoint of cost and solvent solubility, it is preferably 90 mol% or less, more preferably 80 mol% or less, still more preferably 70 mol% or less.

  Further, the epoxy resin of the present invention may further contain another chemical structure in A in the formula (1), and particularly includes a chemical structure represented by the following formula (4). It is preferable. More specifically, from the viewpoint of solvent solubility and cost, the chemical structure represented by the formula (4) is preferably 5 mol% or more with respect to the total number of moles of A, preferably 10 It is more preferably at least mol%, further preferably at least 20 mol%, particularly preferably at least 30 mol%. On the other hand, from the viewpoint of effectively expressing heat resistance and low hygroscopicity according to the formula (2), it is preferably 90 mol% or less, more preferably 80 mol% or less, and 70 mol% or less. More preferably it is.

(In the above formula (4), X ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, —SO ₂ —, —C (CF ₃ ) ₂ — and — And is a group selected from CO-, R ^{11 to} R ¹⁸ may be different from each other, and are a group selected from a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, or a halogen element.)

In the formula (4), X ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, a group selected from —O—, —S—, —SO 2 — and —CO—.

Here, as a C1-C13 bivalent hydrocarbon group in X < ³ > of said Formula (4), the following are mentioned. For example, —CH ₂ —, —CH (CH ₃ ) —, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, —CHPh—, —C (CH ₃ ) Ph—, —CPh ₂ — 9,9-fluorenylene group, 1,1-cyclopropylene group, 1,1-cyclobutylene group, 1,1-cyclopentylene group, 1,1-cyclohexylene group, 3,3,5-trimethyl-1 , 1-cyclohexylene group, 1,1-cyclododecylene group, 1,2-ethylene group, 1,2-cyclopropylene group, 1,2-cyclobutylene group, 1,2-cyclopentylene group, 1,2- Cyclohexylene group, 1,2-phenylene group, 1,3-propylene group, 1,3-cyclobutylene group, 1,3-cyclopentylene group, 1,3-cyclohexylene group, 1,3-phenylene group, 1,4-butylene group, 1,4-cycl A loxylene group, a 1,4-phenylene group, and the like.

Among these, X ³ is a direct bond, —CH ₂ —, —CH (CH ₃ ) —, —C (CH ₃ ) because the lower the degree of rotational freedom of the two aromatic rings tends to be superior in heat resistance. ) ₂ −, —C (CF ₃ ) ₂ —, —CHPh—, —C (CH ₃ ) Ph—, —CPh ₂ —, 9,9-fluorenylene group, 1,1-cyclohexylene group, 3,3, Atoms involved in the connection of two aromatic rings such as 5-trimethyl-1,1-cyclohexylene group, 1,1-cyclododecylene group, —O—, —S—, —SO ₂ —, —CO— and the like. Those having a number of 0 or 1 are preferred. Among these, a direct bond, —CH ₂ —, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, and 9,9-fluorenylene group are particularly preferable.

When X ³ is a direct bond, the biphenyl skeleton is 2,2′-biphenyl skeleton, 2,3′-biphenyl skeleton, 2,4′-biphenyl skeleton, 3,3′-biphenyl skeleton, 3, Either a 4′-biphenyl skeleton or a 4,4′-biphenyl skeleton may be used, but a 4,4′-biphenyl skeleton is preferred. On the other hand, X ³ is —CH ₂ —, —CH (CH ₃ ) —, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, —CHPh—, —C (CH ₃ ) Ph—, — CPh ₂ -, 9,9-fluorenylene group, 1,1-cyclohexylene group, 3,3,5-trimethyl-1,1-cyclohexylene group, 1,1-cyclododecylene group, -O -, - S-, In the case of —SO 2 —, —CO— and the like, the bonding positions in these aromatic rings are 2,2′-position, 2,3′-position, 2,4′-position, 3,3′-position, 3 , 4'-position and 4,4'-position, but preferably 4,4'-position.

In the formula (4), R ^{11 to} R ¹⁸ may be different from each other, and are a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryl having 6 to 12 carbon atoms. A group selected from a group, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, or a halogen element.

Here, the following are mentioned as a C1-C12 alkyl group of R < ¹¹ > -R < ¹⁸ > of said Formula (4). For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, cyclopentyl group, n-hexyl group, isohexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, methylcyclohexyl group, n-octyl group, cyclooctyl group, n-nonyl group, 3,3,5-trimethylcyclohexyl group, n- Decyl group, cyclodecyl group, n-undecyl group, n-dodecyl group, cyclododecyl group, benzyl group, methylbenzyl group, dimethylbenzyl group, trimethylbenzyl group, naphthylmethyl group, phenethyl group, 2-phenylisopropyl group, etc. .

Moreover, the following are mentioned as a C1-C12 alkoxy group of R < ¹¹ > -R < ¹⁸ > of said Formula (4). For example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, n-pentoxy group, isopentoxy group, neopentoxy group, tert-pentoxy group, cyclopent Toxyl group, n-hexyloxy group, isohexyloxy group, cyclohexyloxy group, n-heptoxy group, cycloheptoxy group, methylcyclohexyloxy group, n-octyloxy group, cyclooctyloxy group, n-nonyloxy group, 3,3,5-trimethyl Cyclohexyloxy group, n-decyloxy group, cyclodecyloxy group, n-undecyloxy group, n-dodecyloxy group, cyclododecyloxy group, benzyloxy group, methylbenzyloxy group, dimethyl benzyloxy group, trimethylbenzyloxy group, naphthylmethoxy Group, Enechirokishi group, 2-phenyl-iso-propoxy group.

Examples of the aryl group having 6 to 12 carbon atoms of R ^{11 to} R ^{18 in} the formula (4) include the following. For example, phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, ethylphenyl group, styryl group, xylyl group, n-propylphenyl group, isopropylphenyl group, mesityl group, ethynylphenyl group, naphthyl group, And vinyl naphthyl group.
The following are mentioned as a C2-C12 alkenyl group of R < ¹¹ > -R < ¹⁸ > of said Formula (4). For example, vinyl group, 1-propenyl group, 2-propenyl group, 1-methylvinyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1,3-butadienyl group, cyclohexenyl group, cyclohexadienyl Group, cinnamyl group, naphthyl vinyl group and the like.

The following are mentioned as a C2-C12 alkynyl group of R < ¹¹ > -R < ¹⁸ > of said Formula (4). Examples include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1,3-butanedienyl group, phenylethynyl group, naphthylethynyl group and the like.
Examples of the halogen element represented by R ^{11 to} R ^{18 in} the formula (4) include fluorine, chlorine, bromine, and iodine. Among these, fluorine is preferable.

Among the examples given above, as R ^{11 to} R ^{18 in the} formula (4), a hydrogen atom, a carbon number of 1 to
4 is preferable, and a hydrogen atom and a methyl group are particularly preferable. This is because if the substituent is too sterically large, aggregation between molecules is hindered and heat resistance may be reduced. ^Further, when ^R 11 to R ¹⁸ is a hydrocarbon group or a halogen element having 1 to 12 carbon atoms an alkyl group having 1 to 4 carbon ^atoms, preferably the substitution number of ^R 11 to R ¹⁸ is 2 or 4, Furthermore, when the number of substitutions of R ^{11 to} R ¹⁸ is 2, the alkyl group is preferably in the 2-position and 2′-position, and when the number of substitutions of R ^{11 to} R ¹⁸ is 4, The group is 2-position, 2
Preferably in the '-position, 6-position and 6'-position.

  In addition, the ratio of the chemical structure represented by the said Formula (2) and the said Formula (4) can be controlled by the ratio of the raw material demonstrated in the item of the manufacturing method of the below-mentioned epoxy resin. For this reason, in the epoxy resin of the present invention, the proportion of the chemical structure represented by the formula (2) and the formula (4) contained in each of the bifunctional epoxy resin and the bisphenol compound used as raw materials is Assume that the proportion of the chemical structure represented by the formula (2) and the formula (4) contained in the epoxy resin of the present invention is as it is.

<Weight average molecular weight (Mw)>
The weight average molecular weight (Mw) of the epoxy resin of the present invention is 1,000 to 200,000. When the weight average molecular weight is lower than 1,000, the film-forming property and the elongation are low, and when it is higher than 200,000, the handling of the resin becomes difficult. The weight average molecular weight (Mw) of the epoxy resin of the present invention is preferably 2,000 or more, more preferably 5,000 or more, from the viewpoint of improving film-forming properties and stretchability. In view of the above, it is preferably 160,000 or less, more preferably 120,000 or less, and still more preferably 80,000 or less. In addition, the weight average molecular weight and number average molecular weight of an epoxy resin can be measured by the gel permeation chromatography method (GPC method). An example of a more detailed method will be described in the examples described later.

<Epoxy equivalent>
The epoxy resin of the present invention preferably has an epoxy equivalent of 500 g / equivalent or more, more preferably 1,000 g / equivalent or more, and 2,500 g / equivalent from the viewpoint of improving film formability and elongation. More preferably, it is more than equivalent, more preferably 3,500 g / equivalent or more, and most preferably 5,000 g / equivalent or more. On the other hand, from the viewpoint of improving the handleability, it is preferably 100,000 g / equivalent or less, more preferably 50,000 g / equivalent or less, and still more preferably 30,000 g / equivalent or less. 20,000 g / equivalent or less is most preferable. In the present invention, “epoxy equivalent” is defined as “the mass of an epoxy resin containing one equivalent of an epoxy group” and can be measured according to JIS K7236.

<Glass transition temperature (Tg)>
The epoxy resin of this invention is excellent in heat resistance, and heat resistance can be evaluated by a glass transition temperature (Tg). In the epoxy resin of the present invention, the glass transition temperature (Tg) is preferably 110 ° C. or higher, more preferably 130 ° C. or higher, and the upper limit is not particularly limited, but is usually 210 ° C. or lower. The glass transition temperature (Tg) can be measured by a DSC method.

<Method for producing epoxy resin>
The epoxy resin of the present invention can be obtained, for example, by a two-stage method in which a bifunctional epoxy resin represented by the following formula (5) is reacted with a bisphenol compound represented by the following formula (6). It can also be obtained by a one-step method in which a bisphenol compound represented by the following formula (6) is reacted with epihalohydrin. However, since the high-molecular weight epoxy resin can be obtained more easily than the one-step method in the two-step method, it is preferable to use the two-step method.

(In the above formula (5) or (6), A ′ necessarily includes the chemical structure represented by the above formula (2) ′, and m is an average value of the number of repetitions and is 0 or more and 6 or less. In (2) ′, R ′ ^{1 to} R ′ ¹⁰ may be the same as or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a halogen element, and R ′ ^{1 to} R ′. Any two substituents adjacent to each other in the benzene ring of ⁸ may be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1 ′ and k2 ′ may be the same as each other It may be different and represents an integer of 0 to 4. Further, in the above formula (2), A ′ ¹ and A ′ ² may be the same or different from each other, and have 1 carbon atom as a substituent. -12 alkyl group, C1-C12 alkoxy group, C6-C12 aryl group, C1-C12 alkeni Group, an aromatic ring optionally having a group selected from an alkynyl group having 1 to 12 carbon atoms, X ′ ¹ and X ′ ² may be the same or different from each other, and bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, -O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.

[Manufacturing by two-stage method]
An epoxy resin according to another embodiment of the present invention is obtained by reacting a bifunctional epoxy resin represented by the formula (5) with a bisphenol compound represented by the formula (6), and has a weight average molecular weight ( Mw) is 1,000 to 200,000.
The bifunctional epoxy resin used in the production of the epoxy resin of the present invention is an epoxy resin represented by the above formula (5). For example, a bisphenol compound represented by the above formula (6) is converted into a one-step method described later. And an epoxy resin obtained by condensation with epihalohydrin.

In the formula (5), A ′ may or may not contain the chemical structure represented by the formula (2) ′, but A ′ in the formula (6) may be represented by the formula (2). When 'is not included, the formula (5) necessarily includes the chemical structure represented by the formula (2)'. On the other hand, in the formula (6), A ′ may or may not contain the chemical structure represented by the formula (2) ′, but A ′ in the formula (5) may be represented by the formula ( In the case where 2) ′ is not included, the formula (6) necessarily includes the chemical structure represented by the formula (2) ′. That is, the epoxy resin produced by the two-stage method always includes the chemical structure represented by the formula (2) ′, and as long as this is satisfied,
The chemical structure of the formula (2) ′ may be included in any of the bifunctional epoxy resin and the bisphenol compound, and the ratio of the chemical structure is not limited.

Formula (2) 'in R' ¹ to R ^'10 defined preferred ones are the same as the ^R 1 ^{to R 10} in each of the formulas (2). Further, the formula (2) 'in the X' ¹ and X ^'2 and Definition Preferred is the same as ^{X 1} and ^{X 2} in each of the formulas (2). Furthermore, the definitions and preferable ones of A ′ ¹ and A ′ ² in the formula (2) ′ are the same as those of A ¹ and A ² in the formula (2), respectively.

In addition, when A ′ in Formula (5) or Formula (6) does not include the chemical structure of Formula (2) ′, any known chemical structure can be introduced into A ′.
M in said Formula (5) is an average value of the number of repetitions, and is 0 or more and 6 or less.
The bisphenol compound used for the production of the epoxy resin of the present invention is a bisphenol compound represented by the formula (6).

  In the bifunctional epoxy resin or bisphenol compound used for the production of the epoxy resin of the present invention, the chemical structure represented by the formula (2) ′ has the entire A ′ in the formulas (5) and (6). It is preferable that 1-99 mol% is contained with respect to the number of moles. From the viewpoint of sufficiently expressing the heat resistance resulting from the chemical structure represented by the formula (2) ′, the chemical structure represented by the formula (2) ′ is more preferably 10 mol% or more, and still more preferably. Is 20 mol% or more, particularly preferably 30 mol% or more. From the viewpoint of solvent solubility and cost, the chemical structure represented by the above formula (2) ′ is more preferably 90 mol% or less, still more preferably 80 mol% or less, particularly preferably 70 mol% or less. .

  Moreover, it is preferable that the bifunctional epoxy resin or bisphenol compound used for the production of the epoxy resin of the present invention contains a chemical structure represented by the following formula (4) ′. From the viewpoint of solvent solubility and cost, the chemical structure represented by the formula (4) ′ is preferably 1 mol% or more with respect to the total number of moles of A ′ in the formula (5) or the formula (6). More preferably, it is 5 mol% or more, more preferably 10 mol% or more, particularly preferably 20 mol% or more, and most preferably 30 mol% or more. Further, from the viewpoint of sufficiently expressing heat resistance and low hygroscopicity due to A ′, the chemical structure represented by the formula (4) ′ is preferably 99 mol% or less, more preferably 90 mol% or less. More preferably, it is 80 mol% or less, and particularly preferably 70 mol% or less.

(In the above formula (4) ′, X ′ ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, —SO ² —, —C (CF ³ ) ² and And a group selected from —CO—, R ′ ^{11 to} R ′ ¹⁸ may be different from each other, and are a group selected from a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, or a halogen element.

The definitions and preferred ones of X ′ ³ and R ′ ^{11 to} R ′ ^{18 in} the formula (4) ′ are the same as X ³ and R ^{11 to} R ¹⁸ in the formula (4), respectively.
In the production of the epoxy resin of the present invention, the above-mentioned bifunctional epoxy resin and bisphenol compound are used in an equivalent ratio of (epoxy group) :( phenolic hydroxyl group) = 1: 0.90-1.10. It is preferable that It is preferable for this equivalent ratio to be in the above range because high molecular weight can be easily promoted.

  A catalyst may be used for the synthesis of the epoxy resin of the present invention, and any catalyst may be used as long as it has a catalytic ability to promote a reaction between an epoxy group and a phenolic hydroxyl group, an alcoholic hydroxyl group or a carboxyl group. Something like that. For example, alkali metal compounds, organic phosphorus compounds, tertiary amines, quaternary ammonium salts, cyclic amines, imidazoles and the like can be mentioned.

  Specific examples of the alkali metal compound include alkali metal hydroxides such as sodium hydroxide, lithium hydroxide and potassium hydroxide; alkali metal salts such as sodium carbonate, sodium bicarbonate, sodium chloride, lithium chloride and potassium chloride; sodium Examples include alkali metal alkoxides such as methoxide and sodium ethoxide; alkali metal hydrides such as alkali metal phenoxide, sodium hydride and lithium hydride; and alkali metal salts of organic acids such as sodium acetate and sodium stearate.

  Specific examples of the organic phosphorus compound include tri-n-propylphosphine, tri-n-butylphosphine, triphenylphosphine, tetramethylphosphonium bromide, tetramethylphosphonium iodide, tetramethylphosphonium hydroxide, tetrabutylphosphonium hydroxide, Trimethylcyclohexylphosphonium chloride, trimethylcyclohexylphosphonium bromide, trimethylbenzylphosphonium chloride, trimethylbenzylphosphonium bromide, tetraphenylphosphonium bromide, triphenylmethylphosphonium bromide, triphenylmethylphosphonium iodide, triphenylethylphosphonium chloride, triphenylethylphosphonium bromide, G Phenylethyl phosphonium iodide, triphenyl benzyl phosphonium chloride, triphenyl benzyl phosphonium bromide, and the like. Among these, tetrabutylphosphonium hydroxide is preferable.

Specific examples of the tertiary amine include triethylamine, tri-n-propylamine, tri-n-butylamine, triethanolamine, benzyldimethylamine and the like.
Specific examples of the quaternary ammonium salt include tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium hydroxide, triethylmethylammonium chloride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, tetrapropylammonium bromide, Tetrapropylammonium hydroxide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, benzyltributylammonium chloride Id, and phenyl trimethylammonium chloride and the like. Among these, tetramethylammonium hydroxide is preferable.

Specific examples of cyclic amines include 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5,4,0] undecene-7, 1,5-diazabicyclo [4,3,0. ] Nonene-5 etc. are mentioned.
Specific examples of imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole and the like.

Among the catalysts mentioned above, quaternary ammonium salts are preferred. Moreover, a catalyst can use only 1 type and can also be used in combination of 2 or more type.
The amount of catalyst used is usually 0.001 to 1% by weight in the solid content of the reaction. However, when an alkali metal compound is used, the alkali metal component remains in the resulting epoxy resin, and the electronic / electrical component using the same remains. Since there is a possibility of deteriorating the insulating properties, the total atomic content of lithium, sodium and potassium in the epoxy resin is usually 60 ppm or less, preferably 50 ppm or less.

  In addition, when organophosphorus compounds, tertiary amines, quaternary ammonium salts, cyclic amines, imidazoles, etc. are used as catalysts, these remain as catalyst residues in the resulting epoxy resin, and the alkali metal content Since there is a risk of deteriorating the insulating properties of the printed wiring board as well as the residual, the nitrogen content in the epoxy resin is preferably 300 ppm or less, and the phosphorus content in the epoxy resin is preferably 300 ppm or less. is there. More preferably, the content of nitrogen in the epoxy resin is 200 ppm or less, and the content of phosphorus in the epoxy resin is 200 ppm or less.

  The epoxy resin of the present invention may use a reaction solvent in the step of the synthesis reaction at the time of production, and any solvent may be used as long as it dissolves the epoxy resin. Examples include aromatic solvents, ketone solvents, amide solvents, glycol ether solvents, and the like. The solvent may be used alone or in combination of two or more.

Specific examples of the aromatic solvent include benzene, toluene, xylene and the like. Specific examples of the ketone solvent include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, 2-heptanone, 4-heptanone, 2-octanone, cyclohexanone, acetylacetone, dioxane and the like.
Specific examples of the amide solvent include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methylpyrrolidone and the like.

  Specific examples of the glycol ether solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol. Examples include mono-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, propylene glycol monomethyl ether acetate and the like.

The solid concentration in the synthesis reaction during the production of the epoxy resin is preferably 35 to 95% by weight. Further, when a highly viscous product is produced during the reaction, the reaction can be continued by adding an additional solvent. After completion of the reaction, the solvent can be removed or further added as necessary.
In the production of the epoxy resin, the polymerization reaction between the bifunctional epoxy resin and the bisphenol compound is carried out at a reaction temperature at which the used catalyst is not decomposed. If the reaction temperature is too high, the produced epoxy resin may be deteriorated. Conversely, if the temperature is too low, the reaction may not proceed sufficiently. For these reasons, the reaction temperature is preferably 50 to 230 ° C, more preferably 120 to 200 ° C. Moreover, reaction time is 1 to 12 hours normally, Preferably it is 3 to 10 hours. When using a low boiling point solvent such as acetone or methyl ethyl ketone, the reaction temperature can be ensured by carrying out the reaction under high pressure using an autoclave.

[Manufacturing by one-step method]
The epoxy resin of the present invention can also be produced by a one-step method. Specifically, the bisphenol compound represented by the formula (6) may be directly reacted with epihalohydrin. However, as described above, the low-molecular epoxy resin of the present invention produced by the one-step method can be used as a bifunctional epoxy resin in the two-step method.

  In the case of producing the epoxy resin of the present invention by a one-step method, A ′ necessarily contains the chemical structure represented by the formula (2) ′ in the bisphenol compound of the formula (6) used as a raw material. For the same reason as described in the two-step method, the ratio of the formula (2) ′ to the whole A ′ is preferably 1 mol% or more, more preferably 10 mol% or more, further preferably 20 mol% or more, 30 Mole% or more is particularly preferable. Moreover, 99 mol% or less is preferable, 90 mol% or less is more preferable, 80 mol% or less is further more preferable, and 70 mol% or less is especially preferable. When the epoxy resin produced by the one-step method is used as a bifunctional epoxy resin that is a raw material of the two-step method, as described in the two-step method, A in the bisphenol compound of the formula (6) is used. The proportion of the chemical structure represented by “Formula (2)” in “is not particularly limited, and is 0 to 100%.

  The total bisphenol compound used as a raw material is usually 0.8 to 5.5 molar equivalents, more preferably 0.9 to 5 molar equivalents, still more preferably 1.0 to 4.5 molars per equivalent of the phenolic hydroxyl group. Dissolve in an equivalent amount of epihalohydrin to make an equivalent solution. It is preferable that the amount of epihalohydrin is not less than the above lower limit because the molecular weight is not increased more than necessary, the reaction is easily controlled, and an appropriate melt viscosity can be obtained. On the other hand, the amount of epihalohydrin is preferably not more than the above upper limit from the viewpoint of increasing the molecular weight of the resulting epoxy resin.

  Next, while stirring the solution, this is usually 0.5 to 2.0 molar equivalents, more preferably 0.7 to 1.8 molar equivalents, and further preferably 0.9 to 1 molar equivalents per equivalent of phenolic hydroxyl group. An amount of alkali metal hydroxide corresponding to 6 molar equivalents is added as a solid or an aqueous solution and reacted. It is preferable for the amount of the alkali metal hydroxide to be not less than the above lower limit because the unreacted hydroxyl group and the generated epoxy resin are difficult to react and the high molecular weight reaction can be easily controlled. Further, it is preferable that the alkali metal hydroxide is not more than the above upper limit because impurities due to side reactions are not easily generated.

This reaction can be carried out under normal pressure or reduced pressure, and the reaction temperature is usually preferably 20 to 150 ° C., more preferably 30 to 120 ° C., still more preferably 35 to 100 ° C. in the case of reaction under normal pressure. In the case of a reaction under reduced pressure, it is preferably 20 to 100 ° C, more preferably 30 to 90 ° C, still more preferably 35 to 80 ° C. It is preferable that the reaction temperature is equal to or higher than the above lower limit because the reaction can easily proceed. Further, it is preferable that the reaction temperature is equal to or lower than the above upper limit because side reactions are unlikely to proceed, and chlorine impurities are particularly easily reduced.

  In the reaction, the reaction liquid is azeotroped while maintaining a predetermined temperature as required, the condensed liquid obtained by cooling the vaporized vapor is separated into oil / water, and the oil component excluding moisture is returned to the reaction system. To dehydrate. The addition of alkali metal hydroxide is preferably 0.5 to 8 hours, more preferably 1 to 7 hours, and still more preferably 1 to 6 hours, in order to suppress a rapid reaction, intermittently or continuously. Add it. It is preferable for the addition time to be equal to or more than the above lower limit because the reaction can be prevented from proceeding rapidly and the reaction temperature can be easily controlled. It is preferable for the addition time to be less than or equal to the above upper limit because chlorine impurities are less likely to be generated, and from the viewpoint of economy. The total reaction time is usually 1 to 15 hours.

After completion of the reaction, the insoluble by-product salt is removed by filtration or removed by washing with water, and then the unreacted epihalohydrin is removed by distillation under reduced pressure to obtain the desired epoxy resin. As epihalohydrin in this reaction, epichlorohydrin or epibromohydrin is usually used. As the alkali metal hydroxide, sodium hydroxide or potassium hydroxide is usually used.

  In this reaction, quaternary ammonium salts such as tetramethylammonium chloride and tetraethylammonium bromide; tertiary amines such as benzyldimethylamine and 2,4,6-tris (dimethylaminomethyl) phenol; 2-ethyl Catalysts such as imidazoles such as -4-methylimidazole and 2-phenylimidazole; phosphonium salts such as ethyltriphenylphosphonium iodide; phosphines such as triphenylphosphine may be used.

Furthermore, in this reaction, alcohols such as ethanol and isopropanol; ketones such as acetone and methyl ethyl ketone; ethers such as dioxane and ethylene glycol dimethyl ether; glycol ethers such as methoxypropanol; aprotic such as dimethyl sulfoxide and dimethylformamide An inert organic solvent such as a polar solvent may be used.

  Furthermore, when the amount of saponifiable halogen in the epoxy resin obtained as described above is too large, a purified epoxy resin having a sufficiently reduced amount of saponifiable halogen can be obtained by reprocessing. That is, the crude epoxy resin is redissolved in an inert organic solvent such as isopropyl alcohol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, dioxane, methoxypropanol, dimethyl sulfoxide, and the alkali metal hydroxide is added in solid or aqueous solution. The temperature is preferably 30 to 120 ° C., more preferably 40 to 110 ° C., still more preferably 50 to 100 ° C., preferably 0.1 to 15 hours, more preferably 0.3 to 12 hours, still more preferably 0.00. After re-ringing reaction for 5 to 10 hours, excess alkali metal hydroxide or by-product salt is removed by a method such as washing with water, and further the organic solvent is distilled off under reduced pressure and / or steam distillation to hydrolyze. It is possible to obtain an epoxy resin with a reduced amount of reactive halogen. It is preferable that the reaction temperature is not less than the above lower limit and the reaction time is not less than the above lower limit because the re-ring closure reaction easily proceeds. Moreover, since reaction temperature is below the said upper limit and reaction time is below the said upper limit, since it is easy to control high molecular weight reaction, it is preferable.

[Epoxy resin composition]
The epoxy resin composition of the present invention is an epoxy resin composition containing at least the above-described epoxy resin of the present invention and a curing agent. In addition, other epoxy resins, inorganic fillers, coupling agents, and the like can be appropriately blended in the epoxy resin composition of the present invention as necessary. The epoxy resin composition of the present invention is excellent in heat resistance, low linear expansion, low hygroscopicity, flame retardancy, and the like, and provides a cured product that sufficiently satisfies various physical properties required for various applications.

<Curing agent>
A curing agent can be blended with the epoxy resin of the present invention to obtain an epoxy resin composition. In this invention, a hardening | curing agent shows the substance which contributes to the crosslinking reaction and / or chain length extension reaction between the epoxy groups of an epoxy resin. In the present invention, even if what is usually called a “curing accelerator” is a substance that contributes to a crosslinking reaction and / or chain extension reaction between epoxy groups of an epoxy resin, it is regarded as a curing agent. To do.

The content of the curing agent in the epoxy resin composition of the present invention is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the epoxy resin of the present invention. Further, it is more preferably 80 parts by weight or less, and still more preferably 60 parts by weight or less.
In the epoxy resin composition of this invention, when other epoxy resins mentioned later are contained, it is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the total epoxy resin component as a solid content. Further, it is more preferably 80 parts by weight or less, and still more preferably 60 parts by weight or less. In the present invention, the “solid content” means a component excluding the solvent, and includes not only a solid epoxy resin but also a semi-solid or viscous liquid material. The “total epoxy resin component” means the total of the epoxy resin of the present invention and other epoxy resins described later.

  There is no restriction | limiting in particular as a hardening | curing agent used for the epoxy resin composition of this invention, What is generally known as an epoxy resin hardening | curing agent can be used. Preferable ones from the viewpoint of improving heat resistance include phenolic curing agents, amide based curing agents and imidazoles. Examples of phenolic curing agents, amide-based curing agents, imidazoles, and other usable curing agents are listed below.

[Phenolic curing agent]
It is preferable to use a phenol-based curing agent as the curing agent from the viewpoint of improving the handleability of the resulting epoxy resin composition and the heat resistance after curing. Specific examples of the phenolic curing agent include bisphenol A, bisphenol F, 4,4′-dihydroxydiphenylmethane, 4,4′-dihydroxydiphenyl ether, 1,4-bis (4-hydroxyphenoxy) benzene, 1,3-bis. (4-hydroxyphenoxy) benzene, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolak, bisphenol A novolak, o-cresol novolak, m-cresol novolak, p-cresol Novo Lac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcin, catechol, t-butylcatechol, t-butylhydroquinone, fluoroglycinol, pyrogallol, t-butyl pyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2 , 4-Benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydride Examples include xinaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated or polyallylated dihydroxynaphthalene, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak, allylated pyrogallol, etc. .

  The phenolic curing agents mentioned above may be used alone or in a combination of two or more in any combination and ratio. Moreover, when a hardening | curing agent is a phenol type hardening | curing agent, it is preferable to use so that it may become the range of 0.8-1.5 by the equivalent ratio of the functional group in a hardening | curing agent with respect to the epoxy group in an epoxy resin. Within this range, unreacted epoxy groups and functional groups of the curing agent are unlikely to remain, which is preferable.

[Amide-based curing agent]
It is preferable to use an amide-based curing agent as the curing agent from the viewpoint of improving heat resistance and the like. Use of an amide type curing agent as the curing agent is preferable from the viewpoint of improving the heat resistance of the resulting epoxy resin composition. Examples of the amide-based curing agent include dicyandiamide and derivatives thereof, and polyamide resins.

The phenolic curing agents listed above may be used alone or in a combination of two or more in any combination and ratio. Moreover, it is preferable to use an amide type hardening | curing agent in 0.1-20 weight% with respect to the sum total of all the epoxy resin components and amide type hardening | curing agents as solid content in an epoxy resin composition.

[Imidazoles]
It is preferable to use imidazoles as the curing agent from the viewpoint of sufficiently proceeding the curing reaction and improving the heat resistance. Examples of imidazoles include 2-phenylimidazole, 2-ethyl-4 (5) -methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1 -Cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino- 6- [2′-Methylimidazolyl- (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-tri Azine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and an epoxy resin and the above imidazoles Examples include adducts. In addition, since imidazoles have catalytic ability, they can generally be classified as curing accelerators described later, but in the present invention, they are classified as curing agents.

  The imidazoles listed above may be used alone or in combination of two or more in any combination and ratio. Moreover, it is preferable to use imidazole in 0.1-20 weight% with respect to the sum total of all the epoxy resin components and imidazoles as solid content in an epoxy resin composition.

[Other curing agents]
As a hardening | curing agent which can be used for the epoxy resin composition of this invention, as a thing other than a phenol type hardening | curing agent, an amide type hardening | curing agent, and imidazoles, for example, an amine hardening | curing agent (however, a tertiary amine is remove | excluded. ), Acid anhydride curing agents, tertiary amines, organic phosphines, phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, boron halide amine complexes, polymercaptan curing agents, isocyanate curing agents, block isocyanates Examples thereof include a curing agent. The other hardening | curing agent quoted above may be used only by 1 type, and may mix and use 2 or more types by arbitrary combinations and a ratio.

<Other epoxy resins>
The epoxy resin composition of the present invention can contain other epoxy resins in addition to the epoxy resin of the present invention. By using other epoxy resins, the insufficient physical properties can be compensated or various physical properties can be improved.
The other epoxy resin preferably has two or more epoxy groups in the molecule, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin. Bisphenol Z type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin, etc. Various epoxy resins can be used. These can be used alone or as a mixture of two or more.

In particular, when an epoxy resin of the present invention having a weight average molecular weight (Mw) in a relatively low molecular weight region of 1,000 to 8,000 is used, other epoxy resins used in combination have a weight average molecular weight ( Mw) is preferably 10,000 or more, and more preferably 15,000 or more. When the weight average molecular weight of the other epoxy resin is not less than the above lower limit, the film-forming property of the epoxy resin composition tends to be improved. Although there is no restriction | limiting in particular about the upper limit of the weight average molecular weight of another epoxy resin, Usually, it is 20,000 or less, It is preferable that it is 120,000 or less, It is more preferable that it is 80,000 or less, 50, More preferably, it is 000 or less.

  When the epoxy resin of the present invention has a relatively high molecular weight range with a weight average molecular weight (Mw) of 8,000 to 100,000, other epoxy resins used in combination are 3 in the molecule. A polyfunctional epoxy resin having at least one epoxy group is preferred. When the other epoxy resin is a polyfunctional epoxy resin, the crosslinking density can be improved when the epoxy resin composition is cured, and the heat resistance and flame retardancy tend to be better.

  In the epoxy resin composition of the present invention, when the epoxy resin of the present invention and another epoxy resin are used, the amount of the other epoxy resin in the total epoxy resin component as a solid content is preferably 1% by weight or more. More preferably 5% by weight or more, still more preferably 10% by weight or more, on the other hand, preferably 99% by weight or less, more preferably 95% by weight or less, still more preferably 90% by weight or less. It is. When the ratio of the other epoxy resin is equal to or more than the above lower limit value, the effect of improving physical properties by blending the other epoxy resin can be sufficiently obtained. On the other hand, when the ratio of the other epoxy resin is not more than the above upper limit value, the effect of the epoxy resin of the present invention is sufficiently exhibited, which is preferable from the viewpoint of obtaining low hygroscopicity.

<Solvent>
The epoxy resin composition containing the epoxy resin of the present invention may be diluted by blending a solvent in order to appropriately adjust the viscosity of the epoxy resin composition at the time of handling during coating film formation. In the epoxy resin composition of the present invention, the solvent is used in order to ensure the handleability and workability in the molding of the epoxy resin composition, and the amount used is not particularly limited. In the present invention, the term “solvent” and the above-mentioned term “solvent” are distinguished from each other depending on the form of use, but the same or different ones may be used independently.

  Examples of the solvent that can be contained in the epoxy resin composition containing the epoxy resin of the present invention include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate, and ethers such as ethylene glycol monomethyl ether. Amides such as N, N-dimethylformamide and N, N-dimethylacetamide, alcohols such as methanol and ethanol, alkanes such as hexane and cyclohexane, and aromatics such as toluene and xylene. The solvent mentioned above may be used only by 1 type, and may mix and use 2 or more types by arbitrary combinations and a ratio.

<Other ingredients>
In the epoxy resin composition containing the epoxy resin of the present invention, components other than those listed above (sometimes referred to as “other components” in the present invention) for the purpose of further improving the functionality. May be included. Such other components include curing accelerators (excluding those contained in “curing agents”), UV inhibitors, antioxidants, coupling agents, plasticizers, fluxes, flame retardants, and colorants. , Dispersants, emulsifiers, low elasticity agents, diluents, antifoaming agents, ion trapping agents, inorganic fillers, organic fillers and the like.

[Cured product]
A cured product obtained by curing the epoxy resin of the present invention with a curing agent has an excellent balance of high heat resistance, low linear expansion, low moisture absorption, flame retardancy, and the like, and exhibits excellent cured properties. Here "
“Curing” means that the epoxy resin composition is intentionally cured by heat and / or light or the like, and the degree of curing may be controlled by desired physical properties and applications. The degree of progression may be completely cured or semi-cured, and is not particularly limited. However, the reaction rate of the curing reaction between the epoxy group and the curing agent is usually 5 to 95%.

  The curing method of the epoxy resin composition when the epoxy resin composition of the present invention is cured or semi-cured to obtain a cured product or semi-cured product varies depending on the blending component and blending amount in the epoxy resin composition, but usually And heating conditions of 80 to 280 ° C. for 60 to 360 minutes. This heating is preferably performed in a two-stage process of primary heating at 80 to 160 ° C. for 10 to 90 minutes and secondary heating at 120 to 200 ° C. for 60 to 150 minutes, and the glass transition temperature (Tg) is In the blending system exceeding the temperature of the secondary heating, it is preferable to further perform the tertiary heating at 150 to 280 ° C. for 60 to 120 minutes. Performing secondary heating and tertiary heating in this manner is preferable from the viewpoint of reducing poor curing.

  When producing a resin semi-cured product, it is preferable to advance the curing reaction of the epoxy resin composition to such an extent that the shape can be maintained by heating or the like. When the epoxy resin composition contains a solvent, usually most of the solvent is removed by a method such as heating, reduced pressure, and air drying, but 5% by mass or less of the solvent remains in the resin semi-cured product. Also good.

[Use]
The epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin have the effect of being excellent in high heat resistance, low hygroscopicity, low linear expansion, flame retardancy, film-forming properties (coatability), extensibility, and the like. Play. For this reason, it can be applied to various fields such as adhesives, paints, materials for civil engineering and construction, insulating materials for electrical / electronic parts, etc., especially as insulating castings, laminated materials, sealing materials, etc. in the electrical / electronic field. Useful. Examples of the use of the epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin include multilayer printed wiring boards, laminates for electric and electronic circuits such as capacitors, film adhesives, adhesives such as liquid adhesives, and semiconductors. A sealing material, an underfill material, a 3D-LSI interchip fill, an insulating sheet, a prepreg, a heat dissipation substrate, and the like are exemplified, but the invention is not limited thereto.

<Laminated board for electrical and electronic circuits>
As described above, the epoxy resin composition of the present invention can be suitably used for applications of laminates for electric / electronic circuits. In the present invention, the “laminate for electric / electronic circuit” is a laminate of a layer containing the epoxy resin composition of the present invention and a conductive metal layer, and is electrically conductive with the layer containing the epoxy resin composition of the present invention. As long as the conductive metal layer is laminated, it can be used as a concept including, for example, a capacitor, not an electric / electronic circuit. In addition, the layer which consists of 2 or more types of epoxy resin compositions may be formed in the laminated board for electric / electronic circuits, and the epoxy resin composition of this invention should just be used in at least 1 layer. . Two or more kinds of conductive metal layers may be formed.
The thickness of the layer made of the epoxy resin composition in the laminate for electric / electronic circuit is usually about 10 to 200 μm. The thickness of the conductive metal layer is usually about 0.2 to 70 μm.

[Conductive metal]
Examples of the conductive metal in the laminate for electric / electronic circuit include metals such as copper and aluminum, and alloys containing these metals. In the present invention, for the conductive metal layer of the laminate for electric / electronic circuit, a metal foil of these metals or a metal layer formed by plating or sputtering can be used.

[Manufacturing method of laminated board for electric / electronic circuit]
As a manufacturing method of the laminated board for electric / electronic circuits in this invention, the following methods are mentioned, for example.
(1) A non-woven fabric or cloth using inorganic and / or organic fiber materials such as glass fiber, polyester fiber, aramid fiber, cellulose, and nanofiber cellulose is impregnated with the epoxy resin composition of the present invention to form a prepreg; After providing a conductive metal layer by conductive metal foil and / or plating, a circuit is formed using a photoresist or the like, and a necessary number of such layers are stacked to form a laminate.
(2) Using the prepreg of (1) as a core material, a layer made of an epoxy resin composition and a conductive metal layer are laminated on it (one side or both sides) (build-up method). The layer made of the epoxy resin composition may contain an organic and / or inorganic filler.
(3) Without using the core material, only the layer made of the epoxy resin composition and the conductive metal layer are alternately laminated to form a laminate for an electric / electronic circuit.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited at all by the following example. In addition, the value of various manufacturing conditions and evaluation results in the following examples has a meaning as a preferable value of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-described upper limit or lower limit value. A range defined by a combination of values of the following examples or values of the examples may be used.

[Method for evaluating physical properties and characteristics]
In the following examples and comparative examples, physical properties and characteristics were evaluated by the methods described in 1) to 5) below.

1) Weight average molecular weight (Mw) and number average molecular weight (Mn)
Using "HLC-8320GPC apparatus" manufactured by Tosoh Corporation, under the following measurement conditions, as standard polystyrene, TSK Standard Polystyrene: F-128 (Mw: 1,090,000, Mn: 1,030,000), F-10 (Mw: 106,000, Mn: 103,000), F-4 (Mw: 43,000, Mn: 42,700), F-2 (Mw: 17,200, Mn: 16,900) A-5000 (Mw: 6,400, Mn: 6,100), A-2500 (Mw: 2,800, Mn: 2,700), A-300 (Mw: 453, Mn: 387) were used. A calibration curve was prepared, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured as polystyrene conversion values.
Column: “TSKGEL SuperHM-H + H5000 + H4000 + H3000 + H2000” manufactured by Tosoh Corporation
Eluent: Tetrahydrofuran Flow rate: 0.5 ml / min
Detection: UV (wavelength 254 nm)
Temperature: 40 ° C
Sample concentration: 0.1% by weight
Injection volume: 10 μl

2) Number of n The value of n in the formula (1) was calculated from the number average molecular weight determined above.

3) Epoxy equivalent Measured according to JIS K 7236 and expressed as a solid content converted value.

4) Glass transition temperature (Tg)
About the film of the epoxy resin from which the solvent was removed by drying or the cured epoxy resin, “DSC7020” manufactured by SII NanoTechnology Co., Ltd. was used.
The glass transition temperature was measured by raising the temperature in min. The glass transition temperature here was measured based on “midpoint glass transition temperature: Tmg” described in JIS K7121 “Plastic Transition Temperature Measurement Method”.

5) Water absorption rate (thin film)
The epoxy resin solution is applied to a separator (silicone-treated polyethylene terephthalate film, thickness: 100 μm) with an applicator, dried at 160 ° C. for 1.5 hours, and then at 200 ° C. for 1.5 hours, and an epoxy resin having a thickness of about 50 μm. A film was obtained. The water absorption after the test piece cut into 4 cm × 4 cm was left in a constant temperature and humidity chamber at 85 ° C. and 85% RH for 168 hours was calculated by the following formula.
(Water absorption rate) = [{(Mass of test piece after standing at 85 ° C. and 85% RH for 168 hours)
− (Mass of test piece before treatment)} / (mass of test piece before treatment)] × 100

[Raw materials]
The raw materials, catalysts, solvents and solvents used in the following examples and comparative examples are as follows.

[Bifunctional epoxy resin]
(A-1): Mitsubishi Chemical Corporation product name “YX4000” (3,3 ′, 5,5′-tetramethyl-4,4′-biphenoldiglycidyl ether, epoxy equivalent 186 g / equivalent)

[Bisphenol compounds]
(B-1): 9,9-bis [4- (4-hydroxyphenoxy) phenyl] fluorene (a compound represented by the following formula, product name: TBIS-PEP, hydroxyl equivalent 267 g / equivalent)
(B-2): Bisphenol fluorenone (hydroxyl equivalent 175 g / equivalent)
(B-3): Bisphenol acetophenone (hydroxyl equivalent 145 g / equivalent)

[catalyst]
(C-1): 40 wt% tetrabutylphosphonium hydroxide aqueous solution (C-2): 27 wt% tetramethylammonium hydroxide aqueous solution

[Solvent / Solvent]
(S-1): Cyclohexanone (S-2): Methyl ethyl ketone (MEK)

[Production and evaluation of epoxy resin]
<Examples 1-1 and 1-2, Comparative Example 1-1>
A bifunctional epoxy resin, a bisphenol compound, a catalyst, and a reaction solvent are placed in a reaction vessel equipped with a stirrer according to the formulation shown in Table 1, and the reaction time and reaction temperature described in Table 1 are obtained under a nitrogen gas atmosphere. Reaction was performed. Then, the solvent for dilution was added and solid content concentration was adjusted. After removing the solvent from the reaction product by a conventional method, the obtained resin was analyzed. The results are shown in Table-2.

[Production and evaluation of epoxy resin composition]
<Example 2-1>
Epoxy resin obtained in Example 1-1, bisphenol A novolac type polyfunctional epoxy resin 80 wt% MEK solution (trade name “157S65B80” manufactured by Mitsubishi Chemical Corporation) and 2-ethyl-4 as a curing agent (5) A 20 wt% MEK solution of methylimidazole (trade name “EMI24” manufactured by Mitsubishi Chemical Corporation) was weighed out so that the mass ratio of the solid content was 95: 5: 0.5, and stirred well. Thus, an epoxy resin composition was obtained. This epoxy resin composition is applied to a separator (silicone-treated polyethylene terephthalate film, thickness: 100 μm) with an applicator, dried and cured at 160 ° C. for 1.5 hours and then at 200 ° C. for 1.5 hours, and a thickness of about 50 μm. A film of cured epoxy resin was obtained. About these, the glass transition point and the water absorption were measured using the above-mentioned method. The results are shown in Table-3. In addition, the meanings of the abbreviations in “Other epoxy resins” and “curing agents” in Table 3 are as follows.

<Comparative Example 2-1>
It implemented by the method similar to Example 2-1 except changing the epoxy resin to be used into what was obtained in Comparative Example 1-1.

[Other epoxy resins]
"157S65B80": Mitsubishi Chemical Corporation bisphenol A novolak type polyfunctional epoxy resin 80 wt% MEK solution

[Curing agent]
"EMI24": 2-ethyl-4 (5) -methylimidazole manufactured by Mitsubishi Chemical Corporation

  From the results shown in Table 2, it can be seen that Example 1-1 is excellent in high heat resistance and low hygroscopicity and particularly excellent in low water absorption as compared with Comparative Example 1-1.

  The epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin have the effect of being excellent in high heat resistance, low hygroscopicity, low linear expansion, flame retardancy, film-forming properties (coatability), extensibility, and the like. Play. For this reason, it can be applied to various fields such as adhesives, paints, materials for civil engineering and construction, insulating materials for electrical / electronic parts, etc., especially as insulating castings, laminated materials, sealing materials, etc. in the electrical / electronic field. Useful. Examples of the use of the epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin include multilayer printed wiring boards, laminates for electric and electronic circuits such as capacitors, film adhesives, adhesives such as liquid adhesives, and semiconductors. A sealing material, an underfill material, a 3D-LSI interchip fill, an insulating sheet, a prepreg, a heat dissipation substrate, and the like are exemplified, but the invention is not limited thereto.

Claims (14)

An epoxy resin represented by the following formula (1) and having a weight average molecular weight of 1,000 to 200,000.

(In the above formula (1), A necessarily includes the chemical structure represented by the above formula (2), R and R ′ may be different from each other, and are a hydrogen atom or a group represented by the above formula (3). And at least one of them is a group represented by the above formula (3), n is an average value of the number of repetitions and is from 1 to 500. In the above formula (2), R ^{1 to} R ¹⁰ are Any two substituents which may be the same or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a halogen element, and adjacent to each other on the benzene ring among R ^{1 to} R ⁸ May be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1 and k2 may be the same or different from each other, and each represents an integer of 0 to 4. in formula (2), a ¹ and a ² may be the being the same or different, location The group is arbitrarily selected from an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 1 to 12 carbon atoms, and an alkynyl group having 1 to 12 carbon atoms. X ¹ and X ² may be the same or different from each other, and may be a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.   The epoxy resin according to claim 1, wherein the chemical structure represented by the formula (2) is contained in the formula (1) in an amount of 1 to 99 mol% based on the total number of moles of A. In the formula (1), A includes a chemical structure represented by the following formula (4), and the chemical structure represented by the formula (4) is included in an amount of 1 to 99 mol% based on the total number of moles of A. The epoxy resin according to claim 1 or 2.

(In the above formula (4), X ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, -O-, -S.
—, —SO ₂ —, —C (CF ₃ ) ₂ — and —CO—, wherein R ^{11 to} R ¹⁸ may be different from each other, and are a hydrogen atom or a hydrocarbon having 1 to 12 carbon atoms. It is a group selected from a group or a halogen element. ) An epoxy resin obtained by reacting a bifunctional epoxy resin represented by the following formula (5) with a bisphenol compound represented by the following formula (6), and having a weight average molecular weight of 1,000 to 200,000. .

(In the above formula (5) or (6), A ′ necessarily includes the chemical structure represented by the above formula (2) ′, m is the average number of repetitions, and is 0 or more and 6 or less. In formula (2) ′, R ′ ^{1 to} R ′ ¹⁰ may be the same as or different from each other, and are a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or a halogen element, and R ′ ^{1 to} R ′. Two arbitrary substituents adjacent to each other on the benzene ring in ' ⁸ may be bonded to each other to form a cyclic structure having 4 to 20 carbon atoms, and k1' and k2 'are the same as each other. Or may be different, and represents an integer of 0 to 4. Furthermore, in the above formula (2), A ′ ¹ and A ′ ² may be the same or different from each other, and carbon as a substituent C1-C12 alkyl group, C1-C12 alkoxy group, C6-C12 aryl group, C1-C12 alkene An aromatic ring optionally having a group selected from a nyl group and an alkynyl group having 1 to 12 carbon atoms, and X ′ ¹ and X ′ ² may be the same as or different from each other; bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, -O -, - S -, - a and a divalent linking group selected from -CO-) - SO _2.   The chemical structure represented by the formula (2) ′ in the formula (5) and / or (6) is 1 to 99 mol% with respect to the total number of moles of A ′. Epoxy resin. In the formulas (5) and (6), A ′ includes a chemical structure represented by the following formula (4) ′, and the chemical structure represented by the formula (4) ′ is based on the total number of moles of A ′. The epoxy resin according to claim 4 or 5, which is contained in an amount of 1 to 99 mol%.

(In the above formula (4) ′, X ′ ³ is a direct bond, a divalent hydrocarbon group having 1 to 13 carbon atoms, —O—, —S—, —SO ₂ —, —C (CF ₃ ) ₂ —. And R ′ ^{11 to} R ′ ¹⁸ may be different from each other and are a group selected from a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, or a halogen element.)   The epoxy resin according to any one of claims 1 to 6, wherein an epoxy equivalent is 500 g / equivalent or more and 100,000 g / equivalent or less. The epoxy resin according to any one of claims 1 to 7, wherein the chemical structure represented by the formula (2) and the chemical structure represented by (2) 'are represented by the following formula (7).

  An epoxy resin composition comprising the epoxy resin according to claim 1 and a curing agent. The epoxy resin composition according to claim 9, comprising 0.1 to 100 parts by weight of the curing agent with respect to 100 parts by weight of the epoxy resin.   The epoxy resin composition according to claim 9 or 10, further comprising another epoxy resin, wherein 1 to 99% by weight of the other epoxy resin is included in the total epoxy resin component as a solid content.   The epoxy resin according to any one of claims 9 to 11, further comprising another epoxy resin and 0.1 to 100 parts by weight of the curing agent with respect to 100 parts by weight of the total epoxy resin component as a solid content. Composition.   Hardened | cured material formed by hardening | curing the epoxy resin composition of any one of Claims 9 thru | or 12.   The laminated board for electric / electronic circuits which consists of an epoxy resin composition of any one of Claims 9 thru | or 12.