WO2024024525A1

WO2024024525A1 - Epoxy resin, resin composition thereof, cured object therefrom, and method for producing epoxy resin

Info

Publication number: WO2024024525A1
Application number: PCT/JP2023/025904
Authority: WO
Inventors: 伸悟金光; 正浩宗
Original assignee: 日鉄ケミカル＆マテリアル株式会社
Priority date: 2022-07-26
Filing date: 2023-07-13
Publication date: 2024-02-01
Also published as: TW202413475A

Abstract

Provided are an epoxy resin composition exhibiting excellent low-dielectric properties, an epoxy resin giving the epoxy resin composition, and a method for producing the epoxy resin. The epoxy resin is characterized by comprising an epoxy resin component (A) represented by general formula (1) and an epoxy resin component (B) represented by general formula (5), the proportion of the epoxy resin component (B), as determined by gel permeation chromatography, being in the range of 20-80% by area. In [化1], X represents a group represented by formula (2) or formula (3); Z represents a glycidyl group or a group represented by formula (4); n indicates the number of repetitions; G represents a glycidyl group; R6 represents a C1-C10 hydrocarbon group or a group represented by formula (2a); s1 is 1 or 2; s2 is an integer of 1-5; and s1+s2 is an integer of 2-6.

Description

Epoxy resin, its resin composition, its cured product, and manufacturing method of epoxy resin

The present invention relates to an epoxy resin that provides a cured product with excellent low dielectric properties, an epoxy resin composition containing the epoxy resin as an essential component, and a cured product, prepreg, laminate, or printed wiring board obtained from the epoxy resin composition. , and a method for producing an epoxy resin.

Epoxy resins have excellent adhesiveness, flexibility, heat resistance, chemical resistance, insulation, and curing reactivity, so they are used in a wide variety of applications, including paints, civil engineering adhesives, casting, electrical and electronic materials, and film materials. In particular, epoxy resins are widely used in printed wiring board applications, which are one of the electrical and electronic materials, by imparting flame retardance to them.

In recent years, information devices have rapidly become smaller and more sophisticated, and as a result, materials used in the fields of semiconductors and electronic components are required to have higher performance than ever before. In particular, epoxy resin compositions used as materials for electrical and electronic components are required to have low dielectric properties as substrates become thinner and more functional.

On the other hand, epoxy resins are required not only to have low dielectric properties, but also to have low melt viscosity in order to ensure sealability of circuits on the board. For example, dicyclopentadiene phenol resins with an aliphatic skeleton introduced therein have been proposed to lower the dielectric constant for use in laminates (Patent Documents 1 and 2). However, it was not very effective in improving the dielectric loss tangent, and was not satisfactory in terms of low melt viscosity. Furthermore, it has been proposed to improve dielectric properties by using aromatic-modified dicyclopentadiene phenol resin (Patent Documents 3 and 4). However, it was not possible to achieve both low dielectric properties and low melt viscosity.

Japanese Patent Application Publication No. 2001-240654 Japanese Patent Application Publication No. 5-339341 JP2016-69524A International Publication No. 2022/124252

Therefore, the problem to be solved by the present invention is to provide an epoxy resin that can obtain a cured product that exhibits both low dielectric properties and low melt viscosity and exhibits excellent dielectric properties, an epoxy resin composition using the same, and an epoxy resin composition using the same. The purpose is to provide a manufacturing method.

As a result of various studies conducted by the present inventor in order to solve the above problems, an epoxy resin obtained by epoxidizing a mixture of a specific dicyclopentadiene type polyhydric hydroxy resin and a specific monocyclic phenol compound has a low melt viscosity. The inventors have discovered that a cured product obtained from an epoxy resin composition that essentially includes this epoxy resin has excellent low dielectric properties, and has completed the present invention.

That is, the present invention includes an epoxy resin component (A) represented by the following general formula (1) and an epoxy resin component (B) represented by the following general formula (5), and in gel permeation chromatography measurement, The epoxy resin is characterized in that the epoxy resin component (B) is in a range of 20 to 80% by area.

Here, X is independently a divalent group containing a group represented by the following formula (2) or formula (3), and at least one is represented by formula (2). Z independently represents a glycidyl group or a group represented by the following formula (4). However, at least one of Z in formula (1) and formula (2) is a glycidyl group. n indicates the number of repetitions, and its average value is a number from 0 to 10.

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R2 independently represents a hydrogen atom, a group represented by formula (2a) or formula (2b), and at least one is represented by formula (2a). ) or formula (2b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (2a). A is a residue obtained by removing two R2 from formula (2), and R2 in this case is a hydrogen atom or a group represented by formula (2a). Z independently represents a glycidyl group or a group represented by the following formula (4). Me represents a methyl group. i is an integer from 0 to 2. m1 indicates the number of repetitions, and its average value is a number from 0 to 5. p indicates the number of repetitions, and its average value is a number from 0.01 to 3.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, and j is an integer of 1 to 4.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, and q is an integer of 1 to 5.

Here, G represents a glycidyl group, and R6 independently represents a hydrocarbon group having 1 to 10 carbon atoms or a group represented by the above formula (2a). s1 is 1 or 2, s2 is an integer from 1 to 5, and s1+s2 is an integer from 2 to 6.

The present invention is an epoxy resin obtained by epoxidizing a mixture of a polyhydric hydroxy resin represented by the following general formula (6) and a monocyclic phenol compound represented by the following general formula (7). An epoxy resin characterized in that, in GPC of the epoxy resin, the total amount of the epoxidized product of the monocyclic phenol compound and the epoxidized product of m3=0 body of the polyhydric hydroxy resin is in the range of 20 to 80% by area. .

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R21 independently represents a hydrogen atom, a group represented by formula (6a) or formula (6b), and at least one is represented by formula (6a). ) or formula (6b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (6a). A1 is a residue obtained by removing two R21 from formula (6), and R21 in this case is a hydrogen atom or a group represented by formula (6a). Me represents a methyl group. i is an integer from 0 to 2. m3 indicates the number of repetitions, and its average value is a number from 0 to 5. p1 indicates the number of repetitions, and its average value is a number from 0.01 to 3.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, q1 is 1 or 2, q2 is an integer of 1 to 5, and q1+q2 is an integer of 2 to 6.

The melt viscosity of the epoxy resin at 150°C is preferably 0.001 to 0.10 Pa·s.

The present invention is an epoxy resin composition containing an epoxy resin and a curing agent, and is characterized in that the epoxy resin is essential. The curing agent is preferably a polyhydric hydroxy resin represented by the above general formula (6).

The present invention is a cured product obtained by curing the above epoxy resin composition, and a prepreg, a laminate, or a printed wiring board using the above epoxy resin composition.

The present invention provides phenolic properties of a mixture in which 30 to 300 parts by mass of a monocyclic phenol compound represented by the above general formula (7) is blended with 100 parts by mass of a polyhydric hydroxy resin represented by the above general formula (6). The above-mentioned method for producing an epoxy resin is characterized in that 5 to 20 moles of epihalohydrin are reacted per mole of hydroxyl group in the presence of an alkali metal hydroxide.

The epoxy resin of the present invention has a low melt viscosity, and the cured product using the epoxy resin obtained by the manufacturing method provides an epoxy resin composition that exhibits excellent low dielectric properties.

1 is a GPC chart of the epoxy resin obtained in Example 1. 1 is an IR chart of the epoxy resin obtained in Example 1.

Embodiments of the present invention will be described in detail below.
The epoxy resin of the present invention includes an epoxy resin component (A) represented by the following general formula (1) and an epoxy resin component (B) represented by the following general formula (5) as essential components.
In gel permeation chromatography measurement, the epoxy resin component (B) is in the range of 20 to 80 area%. Preferably, the amount of component (B) is 25 to 70 area %, more preferably 25 to 60 area %.
Here, the epoxy resin component (B) is not only an epoxidized product of a monocyclic phenol compound represented by the general formula (7) used as a raw material, but also a polyhydric hydroxy resin represented by the general formula (6). Among epoxidized products, those in which m3 is 0 (zero) (m3 = 0 body) also fall under this category.

In general formula (1),
X is independently a divalent group containing a group represented by formula (2) or formula (3), and at least one is represented by formula (2).
Z independently represents a glycidyl group or a group represented by formula (4). However, at least one of Z in formula (1) and formula (2) is a glycidyl group.
n indicates the number of repetitions, and its average value is a number from 0 to 10, preferably from 0 to 5.

In general formula (5),
G represents a glycidyl group,
R6 independently represents a hydrocarbon group having 1 to 10 carbon atoms or a group represented by formula (2a).
s1 is the number of glycidyloxy groups, which is 1 or 2,
s2 is the number of substituents R6, and is an integer of 1 to 5, preferably an integer of 1 to 3;
s1+s2 is an integer from 2 to 6, preferably an integer from 2 to 4.

In formula (2),
R1 represents a hydrocarbon group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, an aralkyl group having 7 to 8 carbon atoms, or an allyl group. The alkyl group having 1 to 8 carbon atoms may be linear, branched, or cyclic, such as methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, hexyl group. group, cyclohexyl group, methylcyclohexyl group, etc., but are not limited to these. Examples of the aryl group having 6 to 8 carbon atoms include, but are not limited to, phenyl group, tolyl group, xylyl group, and ethylphenyl group. Examples of the aralkyl group having 7 to 8 carbon atoms include, but are not limited to, benzyl group and α-methylbenzyl group. Among these substituents, phenyl group and methyl group are preferred, and methyl group is particularly preferred, from the viewpoint of availability and reactivity when forming a cured product. The substitution position of R1 may be any of the ortho, meta, and para positions, but the ortho position is preferable.

R2 represents a hydrogen atom or a group represented by formula (2a) or formula (2b), and at least one is represented by formula (2a) or formula (2b). Unlike R1, which is a substituent, R2 does not necessarily represent only a substituent, but also represents a hydrogen atom.
The group represented by general formula (2a) or (2b) is a group derived from a monovinyl compound or a divinyl compound.

i is the number of substituents R1 and is an integer of 0 to 2, preferably 1 or 2, more preferably 2.

Z has the same meaning as Z in formula (1).

m1 indicates the number of repetitions, and its average value (number average) is a number from 0 to 5, preferably from 1.0 to 3.0, more preferably from 1.1 to 3.0, and from 1.2 to 2. 5 is more preferred.

In formula (3),
R5 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. Examples of the hydrocarbon group having 1 to 10 carbon atoms include those similar to R1. From the viewpoint of availability and heat resistance of the cured product, R5 is preferably a hydrogen atom, a methyl group, or an ethyl group, and particularly preferably a hydrogen atom or an ethyl group.
j is the number of substituents R5, and is an integer of 1 to 4, preferably an integer of 1 to 3.

In formula (2a) and formula (2b),
R3 represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. Examples of the hydrocarbon group having 1 to 8 carbon atoms include those similar to R1. Like R2, R3 does not necessarily represent only a substituent, but also represents a hydrogen atom, unlike R1, which is a substituent.
When a monovinyl compound is used as a raw material, R3 is preferably a hydrogen atom, a methyl group, or an ethyl group, and particularly preferably a hydrogen atom or an ethyl group, from the viewpoint of availability and heat resistance of a cured product. When a divinyl compound is used as a raw material, a vinyl group may be included as R3. Further, the substitution position of R3 may be any of the ortho position, meta position, and para position, but the meta position and para position are preferable.
Me represents a methyl group.

In formula (2b),
A is a residue obtained by removing two R2 from formula (2), and R2 in this case is a hydrogen atom or a group represented by formula (2a).
R4 independently represents a hydrogen atom or a group represented by formula (6a).
p is a repeating number, and represents a number of 0 or more, preferably 0.1 to 2.0, more preferably 0.2 to 1.0, and even more preferably 0.3 to 0.8. Its average value is a number from 0.01 to 3.

In formula (4),
R5 is the same as R5 in formula (3).
q is the number of substituents R5, and is an integer of 1 to 5, preferably an integer of 1 to 3.

The epoxy resin of the present invention is preferably obtained by epoxidizing a mixture of a polyhydric hydroxy resin represented by the following general formula (6) and a monocyclic phenol compound represented by the following general formula (7). .

In general formula (6),
R1 and i have the same meanings as R1 and i in formula (2), respectively.
R21 independently represents a hydrogen atom, a group represented by formula (6a) or formula (6b), and at least one is represented by formula (6a) or formula (6b).
m3 indicates the number of repetitions, and its average value is a number from 0 to 5.

In general formula (7),
R5 is the same as R5 in formula (3).
q1 is the number of hydroxyl groups, and is 1 or 2,
q2 is the number of substituents R5, and is an integer of 1 to 5, preferably an integer of 1 to 3;
q1+q2 is an integer of 2 to 6, preferably an integer of 2 to 4.
When the above Z becomes formula (4), a monophenol compound in which q1 of the monocyclic phenol compound of general formula (7) is 1 is used as a raw material, and when no monophenol compound is used, that is, a di- When only a phenol compound (q1=2) is used, all Z's are glycidyl groups.

Formula (6a) is synonymous with formula (2a).

In formula (6b),
Me, R3, and R4 have the same meanings as Me, R3, and R4 in formula (2b), respectively.
A1 is a residue obtained by removing two R21 from formula (6), and R21 in this case is a hydrogen atom or a group represented by formula (6a).
p1 is a repeating number, and is a number of 0 or more, preferably 0.1 to 2.0, more preferably 0.2 to 1.0, and even more preferably 0.3 to 0.8. The average value is a number from 0.01 to 3.

The polyhydric hydroxy resin represented by general formula (6) can be obtained, for example, by the manufacturing method disclosed in Patent Document 4. At this time, the aromatic monovinyl compound and the aromatic divinyl compound used as the raw materials may be used alone, but it is preferable to use them as a mixture. In this case, the blending amount (mass ratio) of aromatic monovinyl compound/aromatic divinyl compound is preferably 15/85 to 50/50, more preferably 17/83 to 45/55. By using this amount, the molecular weight can be easily adjusted and the dielectric properties can be further improved. Note that the polyhydric hydroxy resin used as a raw material may contain an impurity having a structure in which a dicyclopentadiene structure and a phenol hydroxyl group are bonded, but it may be used as is as long as it is in a small amount.

The phenolic hydroxyl equivalent (g/eq.) of the polyhydric hydroxy resin represented by the general formula (6) is preferably from 160 to 400, more preferably from 180 to 350, even more preferably from 200 to 300.
The content determined by GPC is preferably in the range of 10 area % or less of m3 = 0 bodies, 50 to 90 area % of m3 = 1 body, and 0 to 50 area % of m3 = 2 bodies or more.

The phenolic hydroxyl equivalent (g/eq.) of the monocyclic phenol compound represented by general formula (7) is preferably 100 to 300, more preferably 110 to 280, and even more preferably 120 to 260.

Examples of the monocyclic phenol compound represented by the general formula (7) include cresol, ethylphenol, propylphenol, isopropylphenol, n-butylphenol, t-butylphenol, hexylphenol, cyclohexylphenol, phenylphenol, tolylphenol, benzylphenol, α-Methylbenzylphenol, allylphenol, dimethylphenol, t-butyl-dimethylphenol, diethylphenol, dipropylphenol, diisopropylphenol, di(n-butyl)phenol, di(t-butyl)phenol, dihexylphenol, dicyclohexylphenol , diphenylphenol, ditolylphenol, dibenzylphenol, bis(α-methylbenzyl)phenol, methylethylphenol, methylpropylphenol, methylisopropylphenol, methylbutylphenol, methyl-t-butylphenol, methylallylphenol, tolylphenylphenol, Examples include t-butylcatechol, t-butylresorcinol, and t-butylhydroquinone. From the viewpoint of easy availability and reactivity when made into a cured product, cresol, phenylphenol, dimethylphenol, diphenylphenol, t-butylcatechol, t-butylresorcinol, and t-butylhydroquinone are preferred, and t-butylcatechol is preferred. Particularly preferred.　

As a raw material for the epoxy resin of the present invention, the above-mentioned polyhydric hydroxy resin as an essential component and a phenol compound other than the above-mentioned monocyclic phenol compound can be used in combination as long as the effects of the epoxy resin of the present invention are not impaired. The phenol compound that can be used in combination is preferably a monovalent or divalent compound. The amount that can be used in combination is preferably 20% by mass or less, more preferably 10% by mass or less, based on the total amount of the phenol compound component.

The epoxy resin of the present invention includes an epoxy resin component represented by general formula (1) and an epoxy resin component represented by general formula (5). This epoxy resin is obtained by reacting a mixture of a polyhydric hydroxy resin represented by the general formula (6) and a monocyclic phenol compound represented by the general formula (7) with an epihalohydrin such as epichlorohydrin. This epoxidation reaction is carried out according to a conventionally known method.

As a method for epoxidation, for example, a polyvalent hydroxy resin and a monocyclic phenol compound are prepared as raw materials, and epihalohydrin is prepared in an excess molar amount relative to the total hydroxyl groups of the polyvalent hydroxy resin and the monocyclic phenol compound, and these reaction raw materials are prepared. It can be obtained by adding an alkali metal hydroxide such as sodium hydroxide as a solid or concentrated aqueous solution to the mixture and reacting at a reaction temperature of 30 to 120°C for 0.5 to 10 hours. In addition, a quaternary ammonium salt such as tetraethylammonium chloride is added as a catalyst to the reaction raw material mixture, and the resulting polyhalohydrin ether is reacted at a temperature of 50 to 150°C for 1 to 5 hours. It can also be obtained by adding a metal hydroxide as a solid or concentrated aqueous solution and reacting at a temperature of 30 to 120°C for 1 to 10 hours.

In the above reaction, the amount of epihalohydrin used is 1 to 20 times in mole, preferably 2 to 8 times in mole, relative to the total hydroxyl groups of the polyhydric hydroxy resin and the monocyclic phenol compound. The amount of alkali metal hydroxide used is 0.85 to 1.15 times the mole of the total hydroxyl groups of the polyhydric hydroxy resin and monocyclic phenol compound.

Since the epoxy resin obtained by these reactions contains unreacted epihalohydrin and alkali metal halide, the unreacted epihalohydrin is removed by evaporation from the reaction mixture, and the alkali metal halide is further extracted with water. The desired epoxy resin can be obtained by removing it by a method such as , filtration or the like.

The epoxy equivalent (g/eq.) of the epoxy resin of the present invention is preferably 160 to 400,
180-360 is more preferable, and 200-340 is even more preferable.
The melt viscosity at 150° C. is preferably 0.001 to 0.10 Pa·s, more preferably 0.001 to 0.05 Pa·s.
The weight average molecular weight (Mw) is preferably 300 to 2000, more preferably 500 to 1500, and the number average molecular weight (Mn) is preferably 100 to 1000, more preferably 150 to 800.
The total chlorine content is preferably 2000 ppm or less, more preferably 1500 ppm or less.

The epoxy resin composition of the present invention contains an epoxy resin and a curing agent, and has the epoxy resin of the present invention as an essential component. In this embodiment, part or all of the epoxy resin is the epoxy resin of the present invention.

Preferably, 30% by mass or more of the epoxy resin is the epoxy resin of the present invention. The content is more preferably 50% by mass or more, still more preferably 70% by mass or more. If the amount is less than this, the dielectric properties may deteriorate.

As the epoxy resin used in the epoxy resin composition of the present invention, one or more types of various epoxy resins may be used in combination with the epoxy resin of the present invention, if necessary. The amount that can be used in combination is preferably less than 50% by mass, more preferably less than 10% by mass, based on the total amount of the epoxy resin.

As the epoxy resin that can be used in combination, any ordinary epoxy resin having two or more epoxy groups in the molecule can be used. Examples include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol AF epoxy resin, tetramethylbisphenol F epoxy resin, hydroquinone epoxy resin, biphenyl epoxy resin, stilbene epoxy resin, bisphenol fluorene epoxy resin. Resin, bisphenol S type epoxy resin, bisthioether type epoxy resin, resorcinol type epoxy resin, biphenylaralkylphenol type epoxy resin, naphthalene diol type epoxy resin, phenol novolak type epoxy resin, aromatic modified phenol novolac type epoxy resin, cresol novolak type Epoxy resin, alkyl novolac type epoxy resin, bisphenol novolac type epoxy resin, binaphthol type epoxy resin, naphthol novolac type epoxy resin, β-naphthol aralkyl type epoxy resin, dinaphthol aralkyl type epoxy resin, α-naphthol aralkyl type epoxy resin, Tris Trifunctional epoxy resins such as phenylmethane type epoxy resins, tetrafunctional epoxy resins such as tetrakis phenylethane type epoxy resins, dicyclopentadiene type epoxy resins other than the present invention, 1,4-butanediol diglycidyl ether, 1,6- Polyhydric alcohol polyglycidyl ethers such as hexanediol diglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, trimethylolethane polyglycidyl ether, pentaerythritol polyglycidyl ether, alkylene glycol type epoxies such as propylene glycol diglycidyl ether, etc. resins, aliphatic cyclic epoxy resins such as cyclohexanedimethanol diglycidyl ether, glycidyl esters such as dimer acid polyglycidyl ester, phenyldiglycidylamine, tolyldiglycidylamine, diaminodiphenylmethanetetraglycidylamine, aminophenol type epoxy resins, etc. Examples include glycidylamine type epoxy resins, alicyclic epoxy resins such as Celloxide 2021P (manufactured by Daicel Corporation), phosphorus-containing epoxy resins, bromine-containing epoxy resins, urethane-modified epoxy resins, oxazolidone ring-containing epoxy resins, etc. It is not limited. Further, these epoxy resins may be used alone or in combination of two or more. From the viewpoint of ease of availability, epoxy resins represented by the following general formula (8), dicyclopentadiene type epoxy resins other than the present invention, naphthalene diol type epoxy resins, phenol novolak type epoxy resins, aromatic modified phenol novolak type It is more preferable to use an epoxy resin, a cresol novolac type epoxy resin, an α-naphthol aralkyl type epoxy resin, a dicyclopentadiene type epoxy resin, a phosphorus-containing epoxy resin, and an oxazolidone ring-containing epoxy resin.

In general formula (8),
R7 independently represents a hydrocarbon group having 1 to 8 carbon atoms, such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, n-hexyl group, cyclohexyl group. These alkyl groups may be the same or different.
V represents a divalent organic group, for example, an alkylene group such as a methylene group, an ethylene group, an isopropylene group, an isobutylene group, a hexafluoroisopropylidene group, -CO-, -O-, -S-, -SO2- , -SS-, or an aralkylene group represented by formula (8a).
In formula (8a),
R8 independently represents a hydrogen atom or a hydrocarbon group having 1 or more carbon atoms, such as a methyl group, and may be the same or different.
Ar is a benzene ring or a naphthalene ring, and these benzene rings or naphthalene rings include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, and an aryl group having 7 to 11 carbon atoms. It may have an aralkyl group having 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms as a substituent.

Curing agents that are commonly used as curing agents for epoxy resins include various phenolic resins, acid anhydrides, amines, cyanate esters, active esters, hydrazides, acidic polyesters, aromatic cyanates, etc. can be used. A polyhydric hydroxy resin represented by general formula (6) can also be used.
These may be used alone or in combination of two or more.

In the epoxy resin composition of the present invention, the molar ratio of active hydrogen groups in the curing agent is preferably 0.2 to 1.5 mol, preferably 0.3 to 1.4 mol, per 1 mol of epoxy groups in the entire epoxy resin. is more preferable, 0.5 to 1.3 mol is even more preferable, and 0.8 to 1.2 mol is particularly preferable. If it is outside this range, curing may be incomplete and good cured physical properties may not be obtained. For example, when using a phenolic resin curing agent or an amine curing agent, the active hydrogen groups are mixed in approximately equal moles to the epoxy groups. When an acid anhydride curing agent is used, the acid anhydride group is blended in an amount of 0.5 to 1.2 mol, preferably 0.6 to 1.0 mol, per 1 mol of epoxy group. When the phenolic resin of the present invention is used alone as a curing agent, it is preferably used in an amount of 0.9 to 1.1 mol per mol of the epoxy resin.

In the present invention, the active hydrogen group refers to a functional group that has an active hydrogen that is reactive with an epoxy group (including a functional group that has a latent active hydrogen that generates active hydrogen through hydrolysis, etc., and a functional group that exhibits an equivalent curing effect). ), and specific examples include acid anhydride groups, carboxyl groups, amino groups, and phenolic hydroxyl groups. Regarding active hydrogen groups, 1 mole of carboxyl group or phenolic hydroxyl group is calculated as 1 mole, and 2 moles of amino group (NH2). Furthermore, when the active hydrogen group is not clear, the active hydrogen equivalent can be determined by measurement. For example, by reacting a monoepoxy resin such as phenyl glycidyl ether with a known epoxy equivalent with a curing agent with an unknown active hydrogen equivalent, and measuring the amount of monoepoxy resin consumed, the active hydrogen equivalent of the used curing agent can be determined. can be found.

Specific examples of the phenolic resin curing agent that can be used in the epoxy resin composition of the present invention include bisphenol A, bisphenol F, bisphenol C, bisphenol K, bisphenol Z, bisphenol S, tetramethylbisphenol A, and tetramethyl Bisphenols such as bisphenol F, tetramethylbisphenol S, tetramethylbisphenol Z, tetrabromobisphenol A, dihydroxydiphenyl sulfide, 4,4'-thiobis(3-methyl-6-t-butylphenol), catechol, resorcinol, methyl Dihydroxybenzenes such as resorcinol, hydroquinone, monomethylhydroquinone, dimethylhydroquinone, trimethylhydroquinone, mono-t-butylhydroquinone, di-t-butylhydroquinone, and hydroxynaphthalenes such as dihydroxynaphthalene, dihydroxymethylnaphthalene, dihydroxymethylnaphthalene, and trihydroxynaphthalene. phosphorus-containing phenol curing agents such as LC-950PM60 (manufactured by Shin-AT&C), phenol novolac resins such as Shonol BRG-555 (manufactured by Aica Kogyo Co., Ltd.), and DC-5 (manufactured by Nippon Steel Chemical & Materials Co., Ltd.). cresol novolac resins such as (manufactured by Gunei Kagaku Kogyo Co., Ltd.), phenolic resins containing triazine skeletons, aromatic modified phenol novolac resins, bisphenol A novolac resins, trishydroxyphenylmethane type novolac resins such as Resitop TPM-100 (manufactured by Gunei Chemical Industry Co., Ltd.), Phenols such as naphthol novolak resin, condensates of naphthols and/or bisphenols and aldehydes, phenols such as SN-160, SN-395, SN-485 (manufactured by Nippon Steel Chemical & Materials Co., Ltd.), phenol Condensates of phenols and/or naphthols and/or bisphenols with xylylene glycol, condensates of phenols and/or naphthols with isopropenylacetophenone, phenols and/or naphthols and/or bisphenols with dipropylene Reaction products with cyclopentadiene, reaction products with phenols and/or naphthols and/or bisphenols and divinylbenzene, reaction products with phenols and/or naphthols and/or bisphenols and terpenes, phenols and Examples include phenol compounds called so-called novolak phenol resins such as condensates of naphthols and/or bisphenols and biphenyl crosslinking agents, polybutadiene-modified phenol resins, and phenol resins having spiro rings. From the viewpoint of easy availability, phenol novolak resins, dicyclopentadiene phenol resins, trishydroxyphenylmethane type novolak resins, aromatic modified phenol novolak resins, and the like are preferred.

Novolak phenolic resin can be obtained from phenols and a crosslinking agent. Examples of phenols include phenol, cresol, xylenol, butylphenol, amylphenol, nonylphenol, butylmethylphenol, trimethylphenol, phenylphenol, etc.; examples of naphthols include 1-naphthol, 2-naphthol, etc. , the bisphenols mentioned above as the phenolic resin curing agent. Examples of aldehydes as crosslinking agents include formaldehyde, acetaldehyde, propylaldehyde, butyraldehyde, valeraldehyde, capronaldehyde, benzaldehyde, chloraldehyde, bromaldehyde, glyoxal, malonaldehyde, succinaldehyde, glutaraldehyde, adipine aldehyde, and pimeline. Examples include aldehyde, sebacinaldehyde, acrolein, crotonaldehyde, salicylaldehyde, phthalaldehyde, and hydroxybenzaldehyde. Examples of biphenyl crosslinking agents include bis(methylol)biphenyl, bis(methoxymethyl)biphenyl, bis(ethoxymethyl)biphenyl, and bis(chloromethyl)biphenyl.

Specific examples of acid anhydride curing agents include maleic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, and methylbicyclo[2.2.1]heptane-2. , 3-dicarboxylic anhydride, bicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, pyromellitic anhydride, phthalic anhydride, anhydride Examples include trimellitic acid, methylnadic acid, copolymers of styrene monomer and maleic anhydride, and copolymers of indenes and maleic anhydride.

Specific examples of amine curing agents include diethylenetriamine, triethylenetetramine, metaxylene diamine, isophoronediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenyl ether, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl ) Aromatic amines such as phenol, polyether amine, biguanide compounds, dicyandiamide and anisidine, and amine compounds such as polyamide amine which is a condensate of acids such as dimer acid and polyamines.

The cyanate ester compound is not particularly limited as long as it is a compound having two or more cyanate groups (cyanate ester groups) in one molecule. For example, novolak-type cyanate ester curing agents such as phenol novolac type and alkylphenol novolak type, naphthol aralkyl-type cyanate ester-based curing agents, biphenylalkyl-type cyanate ester-based curing agents, dicyclopentadiene-type cyanate ester-based curing agents, and bisphenol A-type curing agents. , bisphenol type cyanate ester curing agents such as bisphenol F type, bisphenol E type, tetramethylbisphenol F type, and bisphenol S type, and prepolymers partially triazinized with these. Specific examples of cyanate ester curing agents include bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate), bis(3-methyl-4-cyanatophenyl)methane, bis(3-methyl-4-cyanatophenyl)methane, -ethyl-4-cyanatophenyl)methane, bis(4-cyanatophenyl)-1,1-ethane, 4,4-dicyanate-diphenyl, 2,2-bis(4-cyanatophenyl)-1,1,1, 3,3,3-hexafluoropropane, 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4- cyanate) phenylpropane, 1,1-bis(4-cyanatophenylmethane), bis(4-cyanato-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatophenyl-1-(methylethylidene)) ) Benzene, bifunctional cyanate resins such as bis(4-cyanatophenyl)thioether, bis(4-cyanatophenyl)ether, tris(4-cyanatophenyl)-1,1,1-ethane, bis(3,5-dimethyl) -4-cyanatophenyl) -4-cyanatophenyl-1,1,1-ethane and other trivalent phenol cyanate esters, phenol novolacs, cresol novolacs, polyfunctional resins derived from dicyclopentadiene structure-containing phenolic resins, etc. Examples include cyanate resins and prepolymers in which these cyanate resins are partially triazinized.One type or two or more types of these can be used.

The active ester curing agent is not particularly limited, but generally contains ester groups with high reactivity such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds in one molecule. A compound having two or more is preferably used. The active ester curing agent is preferably one obtained by a condensation reaction between a carboxylic acid compound and/or a thiocarboxylic acid compound and a hydroxy compound and/or a thiol compound. Particularly from the viewpoint of improving heat resistance, active ester curing agents obtained from a carboxylic acid compound and a hydroxy compound are preferred, and active ester curing agents obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound are more preferred. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenolic compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol , dicyclopentadienyl diphenol, dicyclopentadiene phenol resin which is a raw material for the epoxy resin of the present invention, phenol novolac, and the like. One type or two or more types of active ester curing agents can be used. Examples of active ester curing agents include active ester curing agents containing a dicyclopentadienyl diphenol structure, active ester curing agents containing a naphthalene structure, and active ester curing agents that are acetylated products of phenol novolak. , active ester curing agents that are benzoylated products of phenol novolac are preferred, and among them, active esters containing a dicyclopentadienyl diphenol structure, which is a raw material for the epoxy resin of the present invention, are preferred because they are excellent in improving peel strength. A curing agent based on the curing agent is more preferable.

Examples of other curing agents include phosphine compounds such as triphenylphosphine, phosphonium salts such as tetraphenylphosphonium bromide, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, and 2-methylimidazole. Imidazoles such as decyl imidazole and 1-cyanoethyl-2-methylimidazole, imidazole salts which are salts of imidazoles and trimellitic acid, isocyanuric acid, or boron, etc., quaternary ammonium salts such as trimethylammonium chloride, diazabicyclo compounds, Examples include salts of diazabicyclo compounds and phenols, phenol novolac resins, etc., complex compounds of boron trifluoride and amines, ether compounds, etc., aromatic phosphonium salts, or iodonium salts.

A curing accelerator can be used in the epoxy resin composition if necessary. Examples of curing accelerators that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole, 4-dimethylaminopyridine, 2-(dimethylaminomethyl)phenol, 1, Tertiary amines such as 8-diaza-bicyclo(5,4,0)undecene-7, phosphines such as triphenylphosphine, tricyclohexylphosphine, triphenylphosphine triphenylborane, and metal compounds such as tin octylate. Can be mentioned. When a curing accelerator is used, the amount used is preferably 0.02 to 5 parts by weight based on 100 parts by weight of the epoxy resin component in the epoxy resin composition of the present invention. By using a curing accelerator, it is possible to lower the curing temperature and shorten the curing time.

An organic solvent or a reactive diluent can be used in the epoxy resin composition to adjust the viscosity.

Examples of organic solvents include amides such as N,N-dimethylformamide and N,N-dimethylacetamide, and ethers such as ethylene glycol monomethyl ether, dimethoxydiethylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, and triethylene glycol dimethyl ether. Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methanol, ethanol, 1-methoxy-2-propanol, 2-ethyl-1-hexanol, benzyl alcohol, ethylene glycol, propylene glycol, butyl diglycol , alcohols such as pine oil, acetate esters such as butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, cellosolve acetate, ethyl diglycol acetate, propylene glycol monomethyl ether acetate, carbitol acetate, benzyl alcohol acetate, and benzoic acid. Benzoic acid esters such as methyl and ethyl benzoate, cellosolves such as methyl cellosolve, cellosolve, and butyl cellosolve, carbitols such as methyl carbitol, carbitol, butyl carbitol, and aromas such as benzene, toluene, and xylene. Examples include, but are not limited to, group hydrocarbons, dimethyl sulfoxide, acetonitrile, N-methylpyrrolidone, and the like.

Examples of the reactive diluent include monofunctional glycidyl ethers such as allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and tolyl glycidyl ether, and monofunctional glycidyl esters such as neodecanoic acid glycidyl ester. etc., but are not limited to these.

It is preferable to use these organic solvents or reactive diluents alone or in a mixture of multiple types in the resin composition in an amount of 90% by mass or less as non-volatile content, and the appropriate type and amount to be used will depend on the application. Selected appropriately. For example, for printed wiring board applications, it is preferable to use a polar solvent with a boiling point of 160°C or less, such as methyl ethyl ketone, acetone, or 1-methoxy-2-propanol, and the amount used in the resin composition is 40 to 80% by mass in terms of nonvolatile content. is preferred. In addition, for adhesive film applications, it is preferable to use, for example, ketones, acetic esters, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. It is preferably 30 to 60% by mass.

The epoxy resin composition may contain other thermosetting resins and thermoplastic resins as long as the properties are not impaired. For example, phenolic resin, benzoxazine resin, bismaleimide resin, bismaleimide triazine resin, acrylic resin, petroleum resin, indene resin, coumaron indene resin, phenoxy resin, polyurethane resin, polyester resin, polyamide resin, polyimide resin, polyamideimide resin , polyetherimide resin, polyphenylene ether resin, modified polyphenylene ether resin, polyether sulfone resin, polysulfone resin, polyether ether ketone resin, polyphenylene sulfide resin, polyvinyl formal resin, polysiloxane compound, hydroxyl group-containing polybutadiene, etc. Examples include, but are not limited to, alkylene resins containing alkylene resins.

Various known flame retardants can be used in the epoxy resin composition for the purpose of improving the flame retardancy of the resulting cured product. Examples of flame retardants that can be used include halogen flame retardants, phosphorus flame retardants, nitrogen flame retardants, silicone flame retardants, inorganic flame retardants, and organic metal salt flame retardants. From the environmental point of view, halogen-free flame retardants are preferred, and phosphorus-based flame retardants are particularly preferred. These flame retardants may be used alone or in combination of two or more.

As the phosphorus flame retardant, both inorganic phosphorus compounds and organic phosphorus compounds can be used. Examples of inorganic phosphorus compounds include red phosphorus, ammonium phosphates such as monoammonium phosphate, diammonium phosphate, triammonium phosphate, and ammonium polyphosphate, and inorganic nitrogen-containing phosphorus compounds such as phosphoric acid amide. It will be done. Examples of organic phosphorus compounds include aliphatic phosphoric esters, phosphoric ester compounds, condensed phosphoric esters such as PX-200 (manufactured by Daihachi Chemical Industry Co., Ltd.), phosphazenes, phosphonic acid compounds, and phosphinic acids. In addition to general-purpose organic phosphorus compounds such as phosphine oxide compounds, phosphorane compounds, organic nitrogen-containing phosphorus compounds, and metal salts of phosphinic acid, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10- Oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10- Examples include cyclic organic phosphorus compounds such as phosphaphenanthrene-10-oxide, phosphorus-containing epoxy resins that are derivatives of these compounds reacted with compounds such as epoxy resins and phenol resins, and phosphorus-containing curing agents.

The blending amount of the flame retardant is appropriately selected depending on the type of phosphorus-based flame retardant, the components of the epoxy resin composition, and the desired degree of flame retardancy. For example, the phosphorus content in the organic component (excluding organic solvent) in the epoxy resin composition is preferably 0.2 to 4% by mass, more preferably 0.4 to 3.5% by mass, More preferably, it is 0.6 to 3% by mass. If the phosphorus content is too low, it may be difficult to ensure flame retardancy, and if it is too high, heat resistance may be adversely affected. Further, when using a phosphorus-based flame retardant, a flame retardant aid such as magnesium hydroxide may be used in combination.

A filler can be used in the epoxy resin composition as necessary. Specifically, fused silica, crystalline silica, alumina, silicon nitride, aluminum hydroxide, boehmite, magnesium hydroxide, talc, mica, calcium carbonate, calcium silicate, calcium hydroxide, magnesium carbonate, barium carbonate, barium sulfate, Boron nitride, carbon, carbon fiber, glass fiber, alumina fiber, silica alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aramid fiber, ceramic fiber, particulate rubber, silicone rubber, thermoplastic elastomer, carbon black, pigment, etc. Can be mentioned. The reason why fillers are generally used is to improve impact resistance. Furthermore, when metal hydroxides such as aluminum hydroxide, boehmite, and magnesium hydroxide are used, they act as flame retardant aids and have the effect of improving flame retardancy. The blending amount of these fillers is preferably 1 to 150% by mass, more preferably 10 to 70% by mass, based on the entire epoxy resin composition. If the amount is too large, the adhesion required for use in laminates may decrease, and the cured product may become brittle and may not have sufficient mechanical properties. Moreover, if the amount of the filler is small, there is a possibility that the effect of the filler, such as improving the impact resistance of the cured product, will not be achieved.

When the epoxy resin composition is used as a plate-like substrate, fibrous fillers are preferred from the viewpoint of dimensional stability, bending strength, etc. More preferably, a glass fiber substrate in which glass fibers are knitted in a mesh pattern is used.

The epoxy resin composition further contains various additives such as a silane coupling agent, an antioxidant, a mold release agent, an antifoaming agent, an emulsifier, a thixotropic agent, a smoothing agent, a flame retardant, and a pigment, as necessary. be able to. The blending amount of these additives is preferably in the range of 0.01 to 20% by mass based on the epoxy resin composition.

By impregnating a fibrous base material with the epoxy resin composition, prepregs used in printed wiring boards and the like can be created. As the fibrous base material, inorganic fibers such as glass, woven or non-woven fabrics of organic fibers such as polyester resin, polyamine resin, polyacrylic resin, polyimide resin, aromatic polyamide resin, etc. can be used, but are not limited thereto. It's not something you can do. The method for producing prepreg from an epoxy resin composition is not particularly limited, and for example, the epoxy resin composition may be impregnated with a resin varnish prepared by adjusting the viscosity with an organic solvent, and then heated and dried. It is obtained by semi-curing (B-staged) a resin component, and can be dried by heating at 100 to 200° C. for 1 to 40 minutes, for example. Here, the amount of resin in the prepreg is preferably 30 to 80% by mass.

To cure the prepreg, a laminated board curing method generally used when manufacturing printed wiring boards can be used, but the method is not limited thereto. For example, when forming a laminate using prepreg, one or more sheets of prepreg are laminated, metal foil is placed on one or both sides to form a laminate, and this laminate is heated and pressurized to integrate the laminate. become Here, as the metal foil, single, alloy, or composite metal foils such as copper, aluminum, brass, and nickel can be used. Then, the prepared laminate is heated under pressure to harden the prepreg, and a laminate can be obtained. At that time, it is preferable that the heating temperature is 160 to 220°C, the pressure is 5 to 50 MPa, and the heating and pressing time is 40 to 240 minutes, so that the desired cured product can be obtained. If the heating temperature is low, the curing reaction will not proceed sufficiently, and if it is high, the epoxy resin composition may begin to decompose. In addition, if the pressure is too low, air bubbles may remain inside the resulting laminate and the electrical properties may deteriorate, while if it is too high, the resin will flow before curing, resulting in a cured product with the desired thickness. There is a possibility that it will not be possible. Furthermore, if the heating and pressurizing time is short, the curing reaction may not proceed sufficiently, and if it is long, the epoxy resin composition in the prepreg may be thermally decomposed, which is not preferable.

An epoxy resin cured product can be obtained by curing the epoxy resin composition in the same manner as known epoxy resin compositions. The method for obtaining a cured product can be the same as for known epoxy resin compositions, such as casting, injection, potting, dipping, drip coating, transfer molding, compression molding, resin sheets, resin Preferred methods include forming a laminate in the form of a coated copper foil, prepreg, etc., and curing it under heat and pressure to form a laminate. The curing temperature at that time is usually 100 to 300°C, and the curing time is usually about 1 to 5 hours.

The cured epoxy resin of the present invention can take the form of a laminate, a molded product, an adhesive, a coating film, a film, etc.

As a result of preparing an epoxy resin composition and evaluating the laminate and cured product by heat curing, it was possible to provide an epoxy curable resin composition that exhibited excellent low dielectric properties in the cured product. Specifically, the dielectric properties include a dielectric constant of 3.20 or less, more preferably 3.10 or less, even more preferably 3.00 or less, a dielectric loss tangent of 0.025 or less, more preferably 0.022 or less, and even more preferably can express 0.020 or less.

The present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" represent parts by mass, "%" represent % by mass, and "ppm" represent ppm by mass. In addition, the measurement methods were as follows.

(1) Hydroxyl group equivalent:
Measurement was performed in accordance with the JIS K0070 standard, and the unit was expressed in "g/eq.". In addition, unless otherwise specified, the hydroxyl group equivalent of the phenol resin means the phenolic hydroxyl group equivalent.

(2) Epoxy equivalent:
Measurement was performed in accordance with the JIS K7236 standard, and the unit was expressed in "g/eq.". Specifically, using an automatic potentiometric titration device (manufactured by Hiranuma Sangyo Co., Ltd., COM-1600ST), using chloroform as a solvent, a brominated tetraethylammonium acetic acid solution was added, and a 0.1 mol/L perchloric acid-acetic acid solution was added. It was titrated with

(3) Melt viscosity:
The viscosity at 150° C. was measured using an ICI viscosity measuring device (manufactured by Toa Kogyo Co., Ltd., CV-1S).

(4) Relative permittivity and dielectric loss tangent:
Measured according to IPC-TM-650 2.5.5.9. Specifically, the sample was dried in an oven set at 105°C for 2 hours, left to cool in a desiccator, and then the relative permittivity and dielectric loss tangent at a frequency of 1 GHz were determined by the capacitance method using a material analyzer manufactured by AGILENT Technologies. It was evaluated by asking for.

(5) GPC (gel permeation chromatography) measurement:
A body (manufactured by Tosoh Corporation, HLC-8220GPC) equipped with a column (manufactured by Tosoh Corporation, TSKgelG4000HXL, TSKgelG3000HXL, TSKgelG2000HXL) in series was used, and the column temperature was set at 40°C. Moreover, tetrahydrofuran (THF) was used as an eluent at a flow rate of 1 mL/min, and a differential refractive index detector was used as a detector. As a measurement sample, 0.1 g of the sample was dissolved in 10 mL of THF, and 50 μL of the solution was filtered with a microfilter. For data processing, GPC-8020 Model II version 6.00 manufactured by Tosoh Corporation was used.

(6) IR:
Using a Fourier transform infrared spectrophotometer (Spectrum One FT-IR Spectrometer 1760X, manufactured by Perkin Elmer Precisely), using a diamond ATR, a sample dissolved in toluene was coated on the ATR, dried, and then the wave number was set to 650. Absorbance was measured at ˜4000 cm ⁻¹ .

The abbreviations used in Examples and Comparative Examples are as follows.

[Epoxy resin]
E1: Epoxy resin obtained in Example 1 E2: Epoxy resin obtained in Example 2 E3: Epoxy resin obtained in Example 3 E4: Epoxy resin obtained in Example 4 E5: Epoxy resin obtained in Example 5 E6: Epoxy resin obtained in Example 6 EH1: Epoxy resin obtained in Reference Example 1 EH2: Epoxy resin obtained in Reference Example 2 EH3: Phenol/dicyclopentadiene type epoxy resin (manufactured by DIC Corporation, HP-7200H, Epoxy equivalent: 280, softening point: 83°C, viscosity at 150°C: 0.40 Pa・s)
EH4: Cyclohexane dimethanol type epoxy resin (manufactured by Nippon Steel Chemical & Materials Co., Ltd., ZX-1658GS, epoxy equivalent 136)

[Curing agent]
P2: Phenol resin obtained in Synthesis Example 1 P3: Phenol novolak resin (manufactured by Aica Kogyo Co., Ltd., Showol BRG-557, hydroxyl equivalent 105, softening point 80°C)

[Curing accelerator]
C1: 2E4MZ: 2-ethyl-4-methylimidazole (Curezol 2E4MZ, manufactured by Shikoku Kasei Kogyo Co., Ltd.)

Synthesis example 1
Into a reaction apparatus consisting of a glass separable flask equipped with a stirrer, a thermometer, a nitrogen blowing tube, a dropping funnel, and a cooling tube, 500 parts of 2,6-xylenol (the following structural formula),

7.3 parts of 47% BF3 ether complex was charged and heated to 100° C. with stirring. While maintaining the same temperature, 67.6 parts of dicyclopentadiene (the following structural formula) (0.12 times mole relative to 2,6-xylenol)

was added dropwise over 1 hour. The mixture was further reacted at a temperature of 115 to 125° C. for 4 hours, and 11 parts of calcium hydroxide was added. Furthermore, 19 parts of a 10% aqueous oxalic acid solution was added. Thereafter, the mixture was heated to 160° C. for dehydration, and then heated to 200° C. under a reduced pressure of 5 mmHg to evaporate and remove unreacted raw materials. 1320 parts of MIBK was added to dissolve the product, and 400 parts of 80°C warm water was added for washing, and the lower layer water tank was separated and removed. Thereafter, under a reduced pressure of 5 mmHg, the mixture was heated to 160° C. to evaporate MIBK to obtain a reddish brown phenol resin (P1). The hydroxyl equivalent is 195, the softening point is 73°C, Mw is 470, Mn is 440, m3 = 0 body content is 2.8 area%, m3 = 1 body content is 86.2 area%, m3 = 2 The content above the body was 11.0 area%.

100 parts of the obtained phenolic resin (P1) and paratoluenesulfonic acid monohydrate were placed in a reaction apparatus consisting of a glass separable flask equipped with a stirrer, a thermometer, a nitrogen blowing tube, a dropping funnel, and a cooling tube. 1.0 part of MIBK and 25 parts of MIBK were added, and the mixture was heated to 120° C. with stirring. While maintaining the same temperature, 30 parts of divinylbenzene (manufactured by Aldrich, divinylbenzene 55%, ethylvinylbenzene 45%) having the following structural formula (0.45 times the mole relative to the phenol resin)

was added dropwise over 1 hour. The reaction was further carried out at a temperature of 120 to 130°C for 4 hours. The product was dissolved by adding 280 parts of MIBK, neutralized with 1.3 parts of sodium bicarbonate, washed with 90 parts of 80°C warm water, and the lower layer water tank was separated and removed. Thereafter, the mixture was heated to 180° C. under a reduced pressure of 5 mmHg to evaporate and remove MIBK, thereby obtaining a reddish-brown phenol resin (P2). The obtained phenol resin (P2) is represented by the following structural formula (6-1). The hydroxyl equivalent was 250, the softening point was 81°C, the Mw was 740, and the Mn was 540.

Here, R22 independently represents a hydrogen atom or a group represented by formula (6a-1) or formula (6b-1), and R42 independently represents a hydrogen atom or a group represented by formula (6a-1). show. A12 is a residue obtained by removing two R22 from formula (6-1). Regarding R22, 38 mol% is a group represented by formula (6a-1), 21 mol% is a group represented by formula (6b-1), and the remainder is a hydrogen atom. m3 is 1.2 on average.

Example 1
In a reaction apparatus equipped with a stirrer, a thermometer, a nitrogen blowing tube, a dropping funnel, and a cooling tube, 50 parts of the phenol resin (P2) obtained in Synthesis Example 1 was added, and 4-t-butylcatechol (TBC: the following structural formula ) 16.6 copies,

185 parts of epichlorohydrin (the following structural formula),

55 parts of diethylene glycol dimethyl ether were added and the mixture was heated to 65°C. While maintaining the temperature at 63 to 67° C. under reduced pressure of 125 mmHg, 35.9 parts of a 49% aqueous sodium hydroxide solution was added dropwise over 4 hours. During this time, epichlorohydrin was azeotroped with water, and the water flowing out was sequentially removed from the system. After the reaction was completed, epichlorohydrin was recovered under conditions of 5 mmHg and 180°C, and 290 parts of MIBK was added to dissolve the product. Thereafter, 90 parts of water was added to dissolve the by-produced common salt, and the solution was allowed to stand to separate and remove the lower layer of salt solution. After neutralization with an aqueous phosphoric acid solution, the resin solution was washed with water until the washing solution became neutral, and filtered. MIBK was distilled off by heating to 180° C. under reduced pressure of 5 mmHg to obtain a reddish brown epoxy resin (E1). The epoxy equivalent was 281, the melt viscosity was 0.030 Pa·s, the Mw was 1218, and the Mn was 435. GPC and IR of the obtained epoxy resin (E1) are shown in FIG. 1 and 2, respectively. In FIG. 1, peak (a) was the epoxy resin component (B) represented by general formula (5), and was 28 area %. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from TBC and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Example 2
A reddish-brown epoxy resin (E2) was obtained by carrying out the same operation as in Example 1, except that the phenol resin (P2) was changed to 33.3 parts and the TBC was changed to 22.1 parts. The epoxy equivalent was 258, the melt viscosity was 0.020 Pa·s, the Mw was 990, and the Mn was 389.
The epoxy resin component (B) represented by general formula (5) was 27% by area. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from TBC and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Example 3
A reddish-brown epoxy resin (E3) was obtained by carrying out the same operation as in Example 1, except that the phenol resin (P2) was changed to 25 parts and the TBC was changed to 24.9 parts. The epoxy equivalent was 233, the melt viscosity was 0.007 Pa·s, the Mw was 752, and the Mn was 336.
The epoxy resin component (B) represented by general formula (5) was 49% by area. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from TBC and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Example 4
A reddish-brown epoxy resin (E4) was obtained by carrying out the same operation as in Example 1, except that the phenol resin (P2) was changed to 20 parts and the TBC was changed to 26.6 parts. The epoxy equivalent was 219, the melt viscosity was 0.007 Pa·s, the Mw was 551, and the Mn was 309.
The epoxy resin component (B) represented by general formula (5) was 56 area %. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from TBC and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Example 5
25 parts of phenol resin (P2), 2,6-xylenol (XL: structural formula below) in place of TBC

A reddish-brown epoxy resin (E5) was obtained by carrying out the same operation as in Example 1 except that 36.6 parts of was used. The epoxy equivalent was 274, the melt viscosity was 0.002 Pa·s, Mw was 470, and Mn was 140.
The epoxy resin component (B) represented by general formula (5) was 54% by area. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from XL and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Example 6
33.3 parts of phenol resin (P2), 6-t-butyl-2,4-xylenol (TBXL: structural formula below) in place of TBC

A reddish-brown epoxy resin (E5) was obtained by carrying out the same operation as in Example 1 except that 47.5 parts of was used. The epoxy equivalent was 297, the melt viscosity was 0.002 Pa·s, the Mw was 514, and the Mn was 244.
The epoxy resin component (B) represented by general formula (5) was 47% by area. Here, the epoxy resin component (B) represented by the general formula (5) includes a component derived from TBXL and a component in which m3 is 0 (zero) among the epoxidized products of the phenol resin (P2).

Reference example 1
The same operation as in Example 1 was performed except that 100 parts of the phenol resin (P2) and TBC were not blended (0 parts) to obtain a reddish brown epoxy resin (EH1). The epoxy equivalent was 349, the melt viscosity was 0.18 Pa·s, Mw was 890, and Mn was 580.
Reference example 2
A pale yellow epoxy resin (EH2) was obtained by carrying out the same operation as in Example 1, except that the phenol resin (P2) was not blended (0 parts) and the TBC was changed to 33.2 parts. The epoxy equivalent was 197, the melt viscosity was 0.001 Pa·s, the Mw was 357, and the Mn was 254.

Table 1 shows the physical properties of the epoxy resins (E1 to E6, EH1 to EH2). In addition, "formula (5) rate" in a table|surface shows the value expressed by area % of the content rate of the epoxy resin component (B) represented by general formula (5).

Example 7
A mixture of 100 parts of epoxy resin (E1) as an epoxy resin, 37.4 parts of phenol resin (P3) as a hardening agent, and 0.40 parts of C1 as a hardening accelerator, MEK, propylene glycol monomethyl ether, N,N - An epoxy resin composition varnish was obtained by dissolving it in a mixed solvent prepared with dimethylformamide. A glass cloth (manufactured by Nittobo Co., Ltd., WEA 7628 XS13, 0.18 mm thick) was impregnated with the obtained epoxy resin composition varnish. The impregnated glass cloth was dried in a hot air circulating oven at 150° C. for 9 minutes to obtain a prepreg.
The obtained prepreg was loosened and passed through a sieve to obtain a prepreg powder with a 100 mesh pass. The obtained prepreg powder was placed in a fluororesin mold and vacuum pressed at 2 MPa under the temperature conditions of 130° C. x 15 minutes + 190° C. x 80 minutes to obtain a 50 mm square x 2 mm thick test piece. Table 2 shows the results of the dielectric constant and dielectric loss tangent of the test pieces.

Examples 8 to 13 and Comparative Examples 1 to 3
The ingredients were mixed in the amounts (parts) shown in Table 2, and the same operations as in Example 7 were performed to obtain test pieces. The curing accelerator was used in an amount that could adjust the varnish gel time to about 300 seconds. The same test as in Example 7 was conducted, and the results are shown in Table 2.

The epoxy resin of the present invention can be used in a wide variety of applications such as paints, civil engineering adhesives, casting, electrical and electronic materials, and film materials.In particular, it is used as an electronic material for high-speed communication equipment, such as printed wiring boards, which are one of the electrical and electronic materials. It is useful as a material with low signal loss in electronic components.

Claims

It contains an epoxy resin component (A) represented by the following general formula (1) and an epoxy resin component (B) represented by the following general formula (5), and in gel permeation chromatography measurement, the epoxy resin component (B) is ) is in the range of 20 to 80% by area.

Here, X is independently a divalent group containing a group represented by the following formula (2) or formula (3), and at least one is represented by formula (2). Z independently represents a glycidyl group or a group represented by the following formula (4). However, at least one of Z in formula (1) and formula (2) is a glycidyl group. n indicates the number of repetitions, and its average value is a number from 0 to 10.

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R2 independently represents a hydrogen atom, a group represented by formula (2a) or formula (2b), and at least one is represented by formula (2a). ) or formula (2b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (2a). A is a residue obtained by removing two R2 from formula (2), and R2 in this case is a hydrogen atom or a group represented by formula (2a). Z independently represents a glycidyl group or a group represented by the following formula (4). Me represents a methyl group. i is an integer from 0 to 2. m1 indicates the number of repetitions, and its average value is a number from 0 to 5. p indicates the number of repetitions, and its average value is a number from 0.01 to 3.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, and j is an integer of 1 to 4.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, and q is an integer of 1 to 5.

Here, G represents a glycidyl group, and R6 independently represents a hydrocarbon group having 1 to 10 carbon atoms or a group represented by the above formula (2a). s1 is 1 or 2, s2 is an integer from 1 to 5, and s1+s2 is an integer from 2 to 6.
It is an epoxy resin obtained by epoxidizing a mixture of a polyhydric hydroxy resin represented by the following general formula (6) and a monocyclic phenol compound represented by the following general formula (7), and the obtained epoxy resin is An epoxy resin characterized in that, in GPC, the total amount of the epoxidized product of the monocyclic phenol compound and the epoxidized product of m3=0 body of the polyhydric hydroxy resin is in the range of 20 to 80% by area.

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R21 independently represents a hydrogen atom, a group represented by formula (6a) or formula (6b), and at least one is represented by formula (6a). ) or formula (6b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (6a). A1 is a residue obtained by removing two R21 from formula (6), and R21 in this case is a hydrogen atom or a group represented by formula (6a). Me represents a methyl group. i is an integer from 0 to 2. m3 indicates the number of repetitions, and its average value is a number from 0 to 5. p1 indicates the number of repetitions, and its average value is a number from 0.01 to 3.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, q1 is 1 or 2, q2 is an integer of 1 to 5, and q1+q2 is an integer of 2 to 6.
The epoxy resin according to claim 1, which has a melt viscosity of 0.001 to 0.10 Pa·s at 150°C.
An epoxy resin composition containing an epoxy resin and a curing agent, the epoxy resin composition comprising the epoxy resin according to claim 1 as essential.
The epoxy resin composition according to claim 4, wherein the curing agent is a polyhydric hydroxy resin represented by the following general formula (6).

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R21 independently represents a hydrogen atom, a group represented by formula (6a) or formula (6b), and at least one is represented by formula (6a). ) or formula (6b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (6a). A1 is a residue obtained by removing two R21 from formula (6), and R21 in this case is a hydrogen atom or a group represented by formula (6a). Me represents a methyl group. i is an integer from 0 to 2. m3 indicates the number of repetitions, and its average value is a number from 0 to 5. p1 indicates the number of repetitions, and its average value is a number from 0.01 to 3.
A prepreg characterized by using the epoxy resin composition according to claim 4.
A laminate using the epoxy resin composition according to claim 4.
A printed wiring board characterized by using the epoxy resin composition according to claim 4.
A cured product obtained by curing the epoxy resin composition according to claim 4.
A method for producing an epoxy resin according to claim 1, wherein a monocyclic phenol compound represented by the following general formula (7) is added to 100 parts by mass of a polyhydric hydroxy resin represented by the following general formula (6). A method for producing an epoxy resin, which comprises reacting 5 to 20 moles of epihalohydrin per mole of phenolic hydroxyl groups in a mixture containing 30 to 300 parts by mass in the presence of an alkali metal hydroxide.

Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R21 independently represents a hydrogen atom, a group represented by formula (6a) or formula (6b), and at least one is represented by formula (6a). ) or formula (6b). R3 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R4 independently represents a hydrogen atom or a group represented by formula (6a). A1 is a residue obtained by removing two R21 from formula (6), and R21 in this case is a hydrogen atom or a group represented by formula (6a). Me represents a methyl group. i is an integer from 0 to 2. m3 indicates the number of repetitions, and its average value is a number from 0 to 5. p1 indicates the number of repetitions, and its average value is a number from 0.01 to 3.

Here, R5 independently represents a hydrocarbon group having 1 to 10 carbon atoms, q1 is 1 or 2, q2 is an integer of 1 to 5, and q1+q2 is an integer of 2 to 6.