Modified epoxy resin, resin composition, cured product, laminate for electric / electronic circuits, and method for producing modified epoxy resin

Abstract

Provided are: a modified epoxy resin having excellent solubility and fluidability; a resin composition comprising the modified epoxy resin and a curing agent; a cured product of the resin composition, which has excellent dielectric properties and heat conductivity; and a laminated board for electric / electronic circuits.　The modified epoxy resin is represented by general formula (1) and has an epoxy equivalent of 200 g / eq. or more and less than 5,000 g / eq. In the formula, X's independently represent a bivalent group, in which 70 mol% or more of the bivalent groups is a monocyclic or condensed polycyclic aromatic hydrocarbon group having 6 to 20 carbon atoms which is selected from the group consisting of a benzene ring group, a naphthalene ring group, an anthracene ring group and a phenanthrene ring group, and each of these monocyclic or condensed polycyclic aromatic hydrocarbon group may have a substituent.

Description

[Technical Field]

[0001] The present invention relates to a modified epoxy resin with excellent solubility and fluidity, a resin composition containing the modified epoxy resin and a curing agent, a cured product thereof with excellent dielectric properties and thermal conductivity, and a laminate for electric and electronic circuits made of the resin composition. [Background technology]

[0002] Epoxy resins are widely used in fields such as paints, civil engineering, adhesives, and electrical materials due to their excellent heat resistance, adhesive properties, chemical resistance, water resistance, mechanical strength, and electrical properties. Furthermore, film-forming properties can be imparted by increasing their molecular weight through various methods. Such high-molecular-weight epoxy resins are called phenoxy resins. In particular, bisphenol A-type phenoxy resins are primarily used as base resins for paint varnishes and film molding, and are added to epoxy resin varnishes to adjust flowability and improve toughness and adhesive properties when cured. Furthermore, those containing phosphorus or bromine atoms in their skeletons are used as flame retardants incorporated into epoxy resin compositions and thermoplastic resins.

[0003] Epoxy resins used in electrical materials such as laminates for electric and electronic circuits require solubility and fluidity in addition to dielectric properties. In recent years, information devices have rapidly become smaller and more powerful, and as a result, materials used in the fields of semiconductors and electronic components are required to have higher performance than ever before, especially excellent dielectric properties and thermal conductivity as substrates become thinner and more functional.

[0004] In response to these demands, a method has been proposed for improving dielectric properties by converting the hydroxyl groups present in the side chains of phenoxy resins into esters using acetyl or benzoyl groups. For example, Patent Document 1 discloses an epoxy resin composition containing, as essential components, an epoxy resin having a 2-acyl-1,3-propyleneglycoxy group in its molecular structure, where the acyl group has 1 to 3 carbon atoms, and a curing agent. Patent Document 2 discloses an epoxy resin composition containing, as essential components, a bisphenol-type epoxy resin having an acyl group in its molecular side chain, where the acyl group has 1 to 3 carbon atoms, and an organic solvent with a solubility parameter of 7.0 to 13.0. Patent Document 3 discloses a phenoxy resin obtained by reacting a bifunctional epoxy resin with a diester compound, and a cured product thereof. However, they do not fully satisfy the required properties of the dielectric properties and thermal conductivity of the cured product, as well as the solubility and fluidity of epoxy resins or phenoxy resins. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-333437 [Patent Document 2] Japanese Patent Application Publication No. 10-168287 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-089165 Summary of the Invention

[0006] The present invention aims to provide a modified epoxy resin having excellent solubility and flowability, and to provide a cured product having excellent dielectric properties and thermal conductivity by curing a resin composition containing the modified epoxy resin.

[0007] In order to solve the above problems, the present inventors have conducted extensive research into modified epoxy resins and have found that modified epoxy resins having a specific structure have excellent solubility and flowability, and further found that cured products obtained by curing resin compositions containing such modified epoxy resins have excellent dielectric properties and thermal conductivity, thereby completing the present invention.

[0008] That is, the present invention relates to a modified epoxy resin represented by the following general formula (1) and having an epoxy equivalent of 200 g / eq. or more and less than 5,000 g / eq. [ka] During the ceremony, X's are independently divalent groups, and 70 mol % or more of them are monocyclic or condensed polycyclic aromatic hydrocarbon groups having 6 to 20 carbon atoms selected from the group consisting of benzene ring groups, naphthalene ring groups, anthracene ring groups, and phenanthrene ring groups, and these monocyclic or condensed polycyclic aromatic hydrocarbon groups may have a substituent. Y is independently a hydrogen atom, an acyl group having 2 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having 2 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of Z is an acyl group. n is the average number of repetitions, and is greater than 0 and less than or equal to 30.

[0009] The number average molecular weight (Mn) of the modified epoxy resin is preferably 150 to 10,000.

[0010] The present invention also provides a resin composition containing the above modified epoxy resin and a curing agent. The resin composition preferably contains 1 to 100 parts by mass of a curing agent relative to 100 parts by mass of the modified epoxy resin.

[0011] The resin composition contains the modified epoxy resin, an epoxy resin, and a curing agent, and the mass ratio of the modified epoxy resin to the epoxy resin can be 99 / 1 to 1 / 99. This resin composition preferably contains 1 to 100 parts by mass of a curing agent per 100 parts by mass of the modified epoxy resin and the epoxy resin combined.

[0012] The curing agent to be blended in the resin composition is at least one selected from the group consisting of acrylic ester resins, melamine resins, urea resins, phenolic resins, acid anhydrides, amine compounds, imidazole compounds, amide compounds, cationic polymerization initiators, organic phosphines, polyisocyanate compounds, blocked isocyanate compounds, carbodiimide compounds, and active ester curing agents.

[0013] The present invention also relates to a cured product obtained by curing the above resin composition. Furthermore, the present invention relates to a laminate for electric / electronic circuits, which is made using the above resin composition.

[0014] The present invention also provides a method for producing a modified epoxy resin, which comprises reacting a bifunctional epoxy resin represented by the following general formula (2) with a compound represented by the following general formula (3) to obtain the modified epoxy resin: [ka] where: X 1 , X 2 are independently divalent groups, and X 1 and X 2 70 mol % or more of the total of the above are monocyclic or condensed polycyclic aromatic hydrocarbon groups having 6 to 20 carbon atoms selected from the group consisting of benzene ring groups, naphthalene ring groups, anthracene ring groups, and phenanthrene ring groups, and these monocyclic or condensed polycyclic aromatic hydrocarbon groups may have a substituent. G is a glycidyl group. Q is independently an acyl group having 2 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more of Q is an acyl group. m is the average number of repetitions, and is between 0 and 6. Here, the compound represented by general formula (3) may be a compound in which at least one Q is an acyl group, or a mixture of a compound in which at least one Q is an acyl group and a compound in which both Qs are hydrogen atoms.

[0015] According to the present invention, a modified epoxy resin with excellent solubility and fluidity can be provided. Furthermore, a resin composition using this modified epoxy resin can provide a cured product with excellent dielectric properties and thermal conductivity. Therefore, the modified epoxy resin and resin composition of the present invention are applicable to a variety of fields, such as adhesives, paints, civil engineering and building materials, and insulating materials for electric and electronic components, and are particularly useful as insulating casting materials, laminate materials, and encapsulating materials in the electric and electronic fields. The modified epoxy resin and resin composition containing the same of the present invention can be suitably used in multilayer printed wiring boards, laminates for electric and electronic circuits such as capacitors, adhesives such as film adhesives and liquid adhesives, semiconductor encapsulating materials, underfill materials, interchip fill materials for 3D-LSI, insulating sheets, prepregs, heat dissipation substrates, and the like. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a GPC chart of the modified epoxy resin of Example 1. [Figure 2] 1 is an IR chart of the modified epoxy resin of Example 1. [Figure 3] 1 is a GPC chart of the modified epoxy resin of Example 6. [Figure 4] 1 is an IR chart of the modified epoxy resin of Example 6. [Figure 5] 1 is a GPC chart of the modified epoxy resin of Example 7. [Figure 6] 1 is an IR chart of the modified epoxy resin of Example 7. DETAILED DESCRIPTION OF THE INVENTION

[0017] The modified epoxy resin of the present invention has an epoxy equivalent represented by general formula (1) of 200 g / eq. or more and less than 5,000 g / eq., and further has some or all of the hydrogen atoms in the secondary hydroxyl groups substituted with acyl groups (Z). [ka]

[0018] The modified epoxy resin of the present invention has a structure in which the hydrogen atom in the secondary hydroxyl group is substituted with an acyl group, and therefore has low polarity and good solubility.

[0019] In general formula (1), X is independently a divalent group containing a monocyclic or fused polycyclic aromatic hydrocarbon structure (Xa group) having 6 to 20 carbon atoms. X is independently either an Xa group or another divalent group (Xb group), and contains 70 mol % or more of Xa groups. Examples of Xb groups include residues obtained by removing two hydroxyl groups from a bifunctional phenol compound that may be used in combination as a raw material, which will be described later.

[0020] The Xa group is a monocyclic or condensed polycyclic aromatic hydrocarbon group having 6 to 20 carbon atoms selected from the group consisting of a benzene ring group, a naphthalene ring group, an anthracene ring group, and a phenanthrene ring group, and is preferably a benzene ring group or a naphthalene ring group.

[0021] These Xa groups may be unsubstituted or may have, as a substituent, 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 aralkyl group having 7 to 13 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an aralkyloxy group having 7 to 13 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkynyl group having 2 to 12 carbon atoms.

[0022] The alkyl group having 1 to 12 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a t-pentyl group, a cyclopentyl group, an n-hexyl group, an isohexyl group, a cyclohexyl group, an n-heptyl group, a cycloheptyl group, a methylcyclohexyl group, an n-octyl group, a cyclooctyl group, an n-nonyl group, a 3,3,5-trimethylcyclohexyl group, an n-decyl group, a cyclodecyl group, an n-undecyl group, an n-dodecyl group, a cyclododecyl group, a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a naphthylmethyl group, a phenethyl group, and a 2-phenylisopropyl group.

[0023] The alkoxy group having 1 to 12 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentoxy group, an isopentoxy group, a neopentoxy group, a t-pentoxy group, a cyclopentoxy group, an n-hexyloxy group, an isohexyloxy group, a cyclohexyloxy group, an n-heptoxy group, a cycloheptoxy group, a methylcyclopentoxy group, an alkoxy group having 1 to 12 carbon atoms ... Examples thereof include a cyclohexyloxy group, an n-octyloxy group, a cyclooctyloxy group, an n-nonyloxy group, a 3,3,5-trimethylcyclohexyloxy group, an n-decyloxy group, a cyclodecyloxy group, an n-undecyloxy group, an n-dodecyloxy group, a cyclododecyloxy group, a benzyloxy group, a methylbenzyloxy group, a dimethylbenzyloxy group, a trimethylbenzyloxy group, a naphthylmethoxy group, a phenethyloxy group, and a 2-phenylisopropoxy group.

[0024] Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, an ethylphenyl 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.

[0025] Examples of the aralkyl group having 7 to 13 carbon atoms include a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a phenethyl group, a 1-phenylethyl group, a 2-phenylisopropyl group, and a naphthylmethyl group.

[0026] Examples of the aryloxy group having 6 to 12 carbon atoms include a phenoxy group, an o-tolyloxy group, an m-tolyloxy group, a p-tolyloxy group, an ethylphenoxy group, a styryloxy group, a xylyloxy group, an n-propylphenoxy group, an isopropylphenoxy group, a mesityloxy group, an ethynylphenoxy group, a naphthyloxy group, and a vinylnaphthyloxy group.

[0027] Examples of the aralkyloxy group having 7 to 13 carbon atoms include a benzyloxy group, a methylbenzyloxy group, a dimethylbenzyloxy group, a trimethylbenzyloxy group, a phenethyloxy group, a 1-phenylethyloxy group, a 2-phenylisopropyloxy group, and a naphthylmethyloxy group.

[0028] Examples of alkenyl groups having 2 to 12 carbon atoms include vinyl, 1-propenyl, 2-propenyl, 1-methylvinyl, 1-butenyl, 2-butenyl, 3-butenyl, 1,3-butadienyl, cyclohexenyl, cyclohexadienyl, cinnamyl, and naphthylvinyl groups.

[0029] Examples of the alkynyl group having 2 to 12 carbon atoms include an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a 2-butynyl group, a 3-butynyl group, a 1,3-butadienyl group, a phenylethynyl group, and a naphthylethynyl group.

[0030] In the modified epoxy resin of the present invention, in general formula (1), X may be a divalent group (Xb group) other than Xa group, as long as the effect is not impaired. The content of Xb groups in X is less than 30 mol%, preferably 25 mol% or less, more preferably 20 mol% or less, and even more preferably 0 mol% (not used). The Xb group is, for example, a divalent hydrocarbon group or a hydrocarbon group which may have in the hydrocarbon chain a group such as -O-, -CO-, -S-, -COO-, -SO-, or -SO2-. Examples of these divalent groups include an aromatic skeleton representing a residual skeleton obtained by removing two hydroxyl groups from an aromatic diol compound, an aliphatic skeleton representing a residual skeleton obtained by removing two hydroxyl groups from an aliphatic diol compound, and an alicyclic general formula skeleton representing a residual skeleton obtained by removing two hydroxyl groups from an alicyclic diol compound. These groups are derived from the residual skeleton obtained by removing two glycidyloxy groups from a difunctional epoxy resin (diglycidyl ether compound), the residual skeleton obtained by removing two ester structures from a diester compound, and the residual skeleton obtained by removing two hydroxyl groups from a difunctional phenol compound.

[0031] Specific examples of aromatic skeletons having a structure in which two hydroxyl groups have been removed from an aromatic diol compound include bisphenol types which may be unsubstituted or have an alkyl group having 1 to 10 carbon atoms as a substituent, such as bisphenol A, bisphenolacetophenone, bisphenol AF, bisphenol AD, bisphenol B, bisphenol BP, bisphenol C, bisphenol E, bisphenol F, bisphenol G, bisphenol M, bisphenol S, bisphenol P, bisphenol PH, bisphenoltrimethylcyclohexane, and bisphenolcyclohexane; benzene types such as dihydroxyphenyls which may be unsubstituted or have an alkyl group having 1 to 10 carbon atoms as a substituent, such as hydroquinone, resorcinol, and catechol; naphthalene types such as dihydroxynaphthalenes which may be unsubstituted or have an alkyl group having 1 to 10 carbon atoms as a substituent; biphenyl types such as dihydroxybiphenyls which may be unsubstituted or have an alkyl group having 1 to 10 carbon atoms as a substituent; bisphenolfluorene and Fluorene-type fluorenes such as bisphenolfluorenes and bisnaphtholfluorenes, which may be unsubstituted or have an alkyl group having 1 to 10 carbon atoms as a substituent, such as biscresolfluorene; 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-HQ), 10-(2,7-dihydroxynaphthyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-NQ), 10-(1 and phosphorus-containing phenols which may be unsubstituted or have an alkyl group, an aryl group or an aralkyl group having 1 to 10 carbon atoms as a substituent, such as 1,4-dihydroxy-2-naphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, diphenylphosphinylhydroquinone, diphenylphosphinyl-1,4-dioxynaphthalene, 1,4-cyclooctylenephosphinyl-1,4-phenyldiol and 1,5-cyclooctylenephosphinyl-1,4-phenyldiol.

[0032] Specific examples of the aliphatic skeleton include alkylene glycol skeletons such as ethylene glycol, propylene glycol, and butylene glycol.

[0033] Specific examples of the alicyclic general formula skeleton include hydrogenated bisphenol skeletons such as hydrogenated bisphenol A, hydrogenated bisphenol F, and hydrogenated bisphenol acetophenone.

[0034] In general formula (1), Y is independently a hydrogen atom, an acyl group having 2 to 20 carbon atoms, or a glycidyl group. When Y is a hydrogen atom, a hydroxyl group is provided at the end, when Y is an acyl group, an ester group is provided at the end, and when Y is a glycidyl group, an epoxy group is provided at the end, so it is advisable to control the ratio depending on the application. In the acyl group (R—CO—), the hydrocarbon group having 1 to 19 carbon atoms represented by R is preferably an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms. The alkyl group having 1 to 12 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a t-pentyl group, a cyclopentyl group, an n-hexyl group, an isohexyl group, a cyclohexyl group, an n-heptyl group, a cycloheptyl group, a methylcyclohexyl group, an n-octyl group, a cyclooctyl group, an n-nonyl group, a 3,3,5-trimethylcyclohexyl group, an n-decyl group, a cyclodecyl group, an n-undecyl group, an n-dodecyl group, and a cyclododecyl group. Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, an ethylphenyl group, a xylyl group, an n-propylphenyl group, an isopropylphenyl group, a mesityl group, a naphthyl group, and a methylnaphthyl group. Examples of the aralkyl group having 7 to 13 carbon atoms include a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a phenethyl group, a 2-phenylisopropyl group, and a naphthylmethyl group. Among these, acyl groups having a hydrocarbon group of 1 to 7 carbon atoms are more preferred, with acetyl, propanoyl, butanoyl, benzoyl and methylbenzoyl groups being even more preferred, and acetyl and benzoyl groups being particularly preferred.

[0035] In general formula (1), Z is an acyl group having 2 to 20 carbon atoms or a hydrogen atom. 5 mol % or more of Z are acyl groups, and the remainder are hydrogen atoms. The content (mol %) of acyl groups in all Z in general formula (1) is also referred to as the acylation rate. The acylation rate is preferably 10 mol% or more, more preferably 30 mol% or more, even more preferably 50 mol% or more, and particularly preferably 70 mol% or more. On the other hand, there is no upper limit to the acylation rate, and it may be 100 mol%, but in terms of reactivity, it is about 95%. When all Z's (100 mol%) are acyl groups, the modified epoxy resin of the present invention does not contain secondary hydroxyl groups, and solubility can be further improved. Improvements in dielectric properties and moisture resistance can also be expected. On the other hand, for example, when fine-tuning adhesion to metals, by leaving some of the Z's as hydrogen atoms, it is possible to intentionally allow an appropriate amount of secondary hydroxyl groups to be present in the modified epoxy resin of the present invention, as long as this does not significantly affect other physical properties such as moisture resistance. Specific examples of the acyl group having 2 to 20 carbon atoms are the same as those exemplified above for Y, and preferred acyl groups are also the same.

[0036] In general formula (1), n ​​is the number of repeating units and is an average value. The value ranges from more than 0 to 30. From the viewpoint of ease of handling, it is preferably more than 0 to 20, more preferably more than 0 to 10. The number n can be calculated from the number average molecular weight (Mn) obtained by GPC measurement.

[0037] The epoxy equivalent (g / eq.) of the modified epoxy resin of the present invention is in the range of 200 or more and less than 5,000. Within this range, the modified epoxy resin of the present invention itself can participate in the curing reaction and be incorporated into a crosslinked structure. The epoxy equivalent is preferably in the range of 200 to 4,000, more preferably in the range of 200 to 3,000.

[0038] The modified epoxy resin of the present invention preferably has a number average molecular weight (Mn) of 150 to 10,000. If Mn is less than 150, it is undesirable because there is a risk of incorporation of less of a structure that improves the flame retardancy of the cured product. If Mn is more than 10,000, it is undesirable because there is a risk of the solution viscosity increasing, making handling difficult during production of the cured product. Mn is more preferably 180 to 7,000, and even more preferably 200 to 5,000. The Mn of the modified epoxy resin can be measured by gel permeation chromatography (GPC) as described in the examples.

[0039] The modified epoxy resin of the present invention has some or all of the secondary hydroxyl groups acylated and can be obtained by various methods. A preferred production method is to react a bifunctional epoxy resin represented by general formula (2) with a diester compound and / or a bifunctional phenol compound represented by general formula (3). [ka]

[0040] In the general formula (2), G is a glycyl group, m is the number of repetitions, and the average value is 0 or more and 6 or less. In general formula (3), Q is independently an acyl group having 2 to 20 carbon atoms or a hydrogen atom. In general formula (3), 5 mol % or more of Q is an acyl group having 2 to 20 carbon atoms, and the remainder is a hydrogen atom. Here, the diester compound represented by general formula (3) is selected from diester compounds in which both Qs are acyl groups, monoester compounds in which one is an acyl group and the other is a hydrogen atom, and diphenol compounds in which both are hydrogen atoms, and may be a diester compound or a monoester compound, or a mixture containing a diester compound and / or a monoester compound. The diester compound is preferably a diester compound in which both Qs are acyl groups, or a mixture in which the main component (50% or more) is a diester compound. The acylation rate decreases when the amount of monoester compound or diphenol compound is large.

[0041] X in general formula (2) 1 , X 2 are independently divalent groups, and X 1 and X 2 At least 70 mol % of the total of X are monocyclic or condensed polycyclic aromatic hydrocarbon groups (Xa groups) having 6 to 20 carbon atoms selected from the group consisting of benzene ring groups, naphthalene ring groups, anthracene ring groups, and phenanthrene ring groups, and these monocyclic or condensed polycyclic aromatic hydrocarbon groups may have a substituent. 1 and X in general formula (3) 2 is selected to give X in general formula (1). Therefore, X in general formula (2) 1 and X in general formula (3) 2 For example, X in general formula (2) 1 , X in general formula (3) 2 However, when one of them contains an Xa group, the other may or may not contain an Xa group.

[0042] When producing the modified epoxy resin of the present invention, a bifunctional epoxy resin, a diester compound, or a bifunctional phenol compound can be used as a raw material, and it is essential that these raw materials have an Xa group. As long as the Xa group accounts for 70 mol % or more of the total divalent groups, a difunctional epoxy resin, diester compound or difunctional phenol compound having another divalent group (Xb group) may be used.

[0043] The bifunctional epoxy resin used in the production method of the present invention is an epoxy resin represented by general formula (2), for example, HO-X 1 Examples of epoxy resins include those obtained by reacting a bifunctional phenol compound represented by —OH with epihalohydrin in the presence of an alkali metal compound. 1 is X in the above general formula (2) 1 is the same as:

[0044] Examples of epihalohydrins include epichlorohydrin and epibromohydrin. Examples of alkali metal compounds 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; alkali metal alkoxides such as sodium methoxide and sodium ethoxide; alkali metal salts of organic acids such as sodium acetate and sodium stearate; alkali metal phenoxides, sodium hydride, and lithium hydride.

[0045] In the reaction of a bifunctional phenol compound with epihalohydrin to obtain the starting epoxy resin, an alkali metal compound is used in an amount of 0.80 to 1.20 times by mole, preferably 0.85 to 1.05 times by mole, relative to the functional groups in the bifunctional phenol compound. Less than this amount is undesirable because the amount of residual hydrolyzable chlorine increases. The alkali metal compound is used in the form of an aqueous solution, an alcohol solution, or a solid.

[0046] In the epoxidation reaction, an excess amount of epihalohydrin is used relative to the bifunctional phenol compound. Typically, 1.5 to 15 moles of epihalohydrin are used per mole of functional groups in the bifunctional phenol compound, preferably 2 to 10 moles, and more preferably 5 to 8 moles. If the amount is greater than this, production efficiency decreases, and if it is less than this, the amount of high molecular weight epoxy resin produced increases, making it unsuitable as a raw material for modified epoxy resins.

[0047] The epoxidation reaction is usually carried out at a temperature of 120°C or lower. If the reaction temperature is high, the amount of so-called difficultly hydrolyzable chlorine increases, making it difficult to achieve high purification. The temperature is preferably 100°C or lower, and more preferably 85°C or lower.

[0048] When a bifunctional phenol compound is reacted with an epihalohydrin, m usually becomes greater than 0. In order to make m 0, an epoxy resin produced by a known method can be highly purified by distillation, crystallization, or the like, or a bifunctional phenol compound can be allylated and then epoxidized by oxidizing the olefin moiety.

[0049] The diester compound used in the production method of the present invention can be obtained, for example, by acylation of a bifunctional phenol compound by a condensation reaction with an acid anhydride of an organic acid, a halide of an organic acid, or an organic acid.

[0050] By using an epoxy resin in which m in general formula (2) is 0 as the raw material, the modified epoxy resin of the present invention will not contain secondary hydroxyl groups, and the dielectric properties and moisture resistance can be further improved. Furthermore, for example, when fine-tuning the adhesion to metal, by using an epoxy resin with an appropriate m number, it is possible to intentionally allow an appropriate amount of secondary hydroxyl groups to be present in the modified epoxy resin of the present invention, as long as this does not significantly affect other physical properties such as moisture resistance.

[0051] The bifunctional epoxy resin or diester compound used in the production method of the present invention contains a monocyclic or condensed polycyclic aromatic hydrocarbon group having 6 to 20 carbon atoms selected from the group consisting of a benzene ring group, a naphthalene ring group, an anthracene ring group, or a phenanthrene ring group.

[0052] The amount of bifunctional epoxy resin and diester compound used is preferably 0.2 to 0.95 equivalents of ester group and / or hydroxyl group per equivalent of epoxy group, more preferably 0.25 to 0.8 equivalents. This equivalent ratio facilitates the promotion of high molecular weight polymerization with epoxy groups at the molecular terminals. It is also possible to replace a portion of the diester compound with a bifunctional phenol compound. As described above, this allows the presence of an appropriate amount of secondary hydroxyl groups in the modified epoxy resin of the present invention, thereby enabling fine adjustment of physical properties. In the production method, a polymerization reaction occurs, the molecular weight increases, and a modified epoxy resin is produced, and at the same time, some of the secondary hydroxyl groups of the modified epoxy resin are esterified.

[0053] A catalyst may be used in the production method. The catalyst may be any compound that has catalytic activity to promote the reaction between the epoxy group and the ester group. Examples of the catalyst include tertiary amines, cyclic amines, imidazole compounds, organic phosphorus compounds, and quaternary ammonium salts. These catalysts may be used alone or in combination of two or more.

[0054] Examples of tertiary amines include triethylamine, tri-n-propylamine, tri-n-butylamine, triethanolamine, benzyldimethylamine, and 2,4,6-tris(dimethylaminomethyl)phenol.

[0055] Examples of cyclic amines include 1,4-diazabicyclo[2,2,2]octane (DABCO), 1,8-diazabicyclo[5,4,0]undecene-7 (DBU), 1,5-diazabicyclo[4,3,0]nonene-5 (DBN), N-methylmorpholine, pyridine, and 4-dimethylaminopyridine (DMAP).

[0056] Examples of imidazole compounds include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2-phenylimidazole.

[0057] Examples of the organic phosphorus compounds include phosphines such as tri-n-propylphosphine, tri-n-butylphosphine, diphenylmethylphosphine, triphenylphosphine, tris(p-tolyl)phosphine, tricyclohexylphosphine, tri(t-butyl)phosphine, tris(p-methoxyphenyl)phosphine, paramethylphosphine, 1,2-bis(dimethylphosphino)ethane, and 1,4-bis(diphenylphosphino)butane; tetramethylphosphonium bromide, tetramethylphosphonium iodide, tetramethylphosphonium hydroxide, and tetrabutylphosphonium hydride; and phosphonium salts such as methyl cyclohexyl phosphonium chloride, trimethyl cyclohexyl phosphonium bromide, trimethyl benzyl phosphonium chloride, trimethyl benzyl phosphonium bromide, tetraphenyl phosphonium bromide, triphenyl methyl phosphonium bromide, triphenyl methyl phosphonium iodide, triphenyl ethyl phosphonium chloride, triphenyl ethyl phosphonium bromide, triphenyl ethyl phosphonium iodide, triphenyl benzyl phosphonium chloride, and triphenyl benzyl phosphonium bromide.

[0058] Examples of quaternary ammonium salts 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, and phenyltrimethylammonium chloride.

[0059] Among the catalysts listed above, 4-(dimethylamino)pyridine, 1,4-diazabicyclo[2,2,2]octane, 1,8-diazabicyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4,3,0]nonene-5, 2-ethyl-4-methylimidazole, tris(p-tolyl)phosphine, tricyclohexylphosphine, tri(t-butyl)phosphine, and tris(p-methoxyphenyl)phosphine are preferred, and 4-(dimethylamino)pyridine, 1,8-diazabicyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4,3,0]nonene-5, and 2-ethyl-4-methylimidazole are particularly preferred.

[0060] The amount of catalyst used is usually 0.001 to 1 mass% of the reaction solids, but when these compounds are used as catalysts, the catalyst remains as residue in the resulting modified epoxy resin, which may deteriorate the insulating properties of the printed wiring board or shorten the pot life of the composition, so the content of catalyst-derived nitrogen in the modified epoxy resin is preferably 0.5 mass% or less, more preferably 0.3 mass% or less. Also, the content of catalyst-derived phosphorus in the modified epoxy resin is preferably 0.5 mass% or less, more preferably 0.3 mass% or less.

[0061] In the production method of the present invention, a reaction solvent may be used, and any solvent that can dissolve the modified epoxy resin may be used. Examples of the solvent include aromatic solvents, ketone solvents, amide solvents, glycol ether solvents, and ester solvents. These solvents may be used alone or in combination of two or more.

[0062] Examples of aromatic solvents include benzene, toluene, and xylene.

[0063] Examples of ketone solvents include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, 2-heptanone, 4-heptanone, 2-octanone, cyclohexanone, acetylacetone, diisobutyl ketone, isophorone, methylcyclohexanone, and acetophenone.

[0064] Examples of amide solvents include formamide, N-methylformamide, N,N-dimethylformamide (DMF), acetamide, N-methylacetamide, N,N-dimethylacetamide, 2-pyrrolidone, and N-methylpyrrolidone.

[0065] Examples of glycol ether solvents include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and ethylene glycol mono-n-butyl ether; diethylene glycol monoalkyl ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol mono-n-butyl ether; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol mono-n-butyl ether; ethylene glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol dibutyl ether; and polyethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol dibutyl ether. ethylene glycol dialkyl ethers, propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, and propylene glycol dibutyl ether; polypropylene glycol dialkyl ethers such as dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dibutyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, and tripropylene glycol dibutyl ether; ethylene glycol monoalkyl ether acetates such as ethylene glycol monoethyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether acetate; diethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triethylene glycol monomethyl ether acetate, and triethylene glycol monoethyl ether acetate;Examples include polyethylene glycol monoalkyl ether acetates such as triethylene glycol monobutyl ether acetate, and propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monobutyl ether acetate.

[0066] Examples of ester solvents include methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, benzyl acetate, ethyl propionate, ethyl butyrate, butyl butyrate, valerolactone, and butyrolactone.

[0067] Other solvents include, for example, dioxane, dimethyl sulfoxide, sulfolane, γ-butyrolactone, and the like.

[0068] In the production method, the solid content during the reaction is preferably 35 to 100% by mass. If a highly viscous product is produced during the reaction, the reaction can be continued by adding additional solvent. After the reaction is completed, the solvent can be removed or further added as necessary.

[0069] The reaction temperature is set within a range that does not decompose the catalyst used. If the reaction temperature is too high, the catalyst may decompose, halting the reaction or degrading the resulting modified epoxy resin. If the reaction temperature is too low, the reaction may not proceed sufficiently to achieve the desired molecular weight. Therefore, the reaction temperature is preferably 50 to 230°C, more preferably 70 to 210°C, and even more preferably 90 to 200°C. The reaction time is typically 1 to 12 hours, preferably 1.5 to 5 hours. When using a low-boiling solvent such as acetone or methyl ethyl ketone, the reaction temperature can be maintained by conducting the reaction under high pressure using an autoclave. If the heat of reaction needs to be removed, this is typically achieved by evaporating, condensing, and refluxing the solvent using the heat of reaction, indirect cooling, or a combination of these.

[0070] The resin composition of the present invention is a resin composition containing at least the modified epoxy resin of the present invention and a curing agent. Furthermore, various additives such as other epoxy resins, inorganic fillers, coupling agents, and antioxidants can be appropriately blended into the resin composition of the present invention, as needed. The resin composition of the present invention provides a cured product that satisfies the various physical properties required for various applications.

[0071] A resin composition can be prepared by blending a curing agent with the modified epoxy resin of the present invention. In the present invention, the curing agent refers to a substance that contributes to the crosslinking reaction and / or chain extension reaction with the modified epoxy resin. In the present invention, even substances that are normally called "curing accelerators" are considered to be curing agents as long as they contribute to the crosslinking reaction and / or chain extension reaction of the modified epoxy resin.

[0072] The content of the curing agent in the resin composition of the present invention is preferably 0.1 to 100 parts by mass relative to 100 parts by mass of the modified epoxy resin of the present invention, more preferably 0.5 to 80 parts by mass, and even more preferably 1 to 50 parts by mass. Note that this refers to the amount of nonvolatile content (solid content) in the resin composition.

[0073] When the resin composition of the present invention contains other epoxy resins, the mass ratio (solid content) of the modified epoxy resin of the present invention to the other epoxy resin is 99 / 1 to 1 / 99. In the present invention, "solid content" refers to the components excluding the solvent, and includes not only solid modified epoxy resins and epoxy resins, but also semi-solid and viscous liquids. Furthermore, "resin component" refers to the total of the modified epoxy resin of the present invention and the epoxy resin described below.

[0074] The curing agent used in the resin composition of the present invention is not particularly limited, and any curing agent generally known as an epoxy resin curing agent can be used. From the viewpoint of improving heat resistance, preferred curing agents include phenolic resins, amide compounds, imidazole compounds, and active ester curing agents. These curing agents may be used alone or in combination of two or more.

[0075] Examples of phenolic resins 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 novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcinol, catechol, t-butylcatechol, t- Butylhydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, 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, Examples thereof include 8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, and the like, as well as allylated products or polyallylated products of the above dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, allylated phenol novolak, and allylated pyrogallol.

[0076] Examples of the amide compounds include dicyandiamide and its derivatives, polyamide resins, and the like.

[0077] Examples of the imidazole compounds 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'-methylimidazole] Examples of suitable imidazole compounds include 2,4-diamino-6-[2'-ethyl-4'-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-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resins with the above imidazole compounds. Note that, because imidazole compounds have catalytic activity, they can generally be classified as curing accelerators, which will be described later, but in the present invention they are classified as curing agents.

[0078] Examples of active ester curing agents include compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. Among these, phenol esters obtained by reacting a carboxylic acid compound with an aromatic compound having a phenolic hydroxyl group 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 the aromatic compound having a phenolic hydroxyl group include catechol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyldiphenol, and phenol novolak.

[0079] Examples of other curing agents that can be used in the resin composition of the present invention include acrylic ester resins, melamine resins, urea resins, cationic polymerization agents, amine compounds, acid anhydrides, tertiary amines, organic phosphines, phosphonium salts, tetraphenylboron salts, organic acid dihydrazides, boron halide amine complexes, polymercaptan curing agents, isocyanate compounds, polyisocyanate compounds, blocked isocyanate compounds, carbodiimide compounds, etc. These other curing agents may be used alone, or two or more may be mixed in any combination and ratio.

[0080] The resin composition of the present invention can contain epoxy resins other than the modified epoxy resin of the present invention. The use of other epoxy resins can compensate for insufficient physical properties or improve various physical properties. The epoxy resin preferably has two or more epoxy groups in the molecule, and more preferably has three or more epoxy groups. Examples include polyglycidyl ether compounds, polyglycidyl amine compounds, polyglycidyl ester compounds, alicyclic general epoxy compounds, and other modified epoxy resins. These epoxy resins may be used alone, or two or more types of epoxy resins of the same type may be used in combination, or different types of epoxy resins may be used in combination.

[0081] Examples of the polyglycidyl ether compound include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, bisphenol Z type epoxy resins, bisphenol fluorene type epoxy resins, diphenyl sulfide type epoxy resins, diphenyl ether type epoxy resins, naphthalene type epoxy resins, hydroquinone type epoxy resins, resorcinol type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, alkyl novolac type epoxy resins, styrenated phenol novolac type epoxy resins, bisphenol novolac type epoxy resins, naphthol novolac type epoxy resins, phenol aralkyl type epoxy resins, β-naphthol aralkyl type epoxy resins, naphthalenediol aralkyl type epoxy resins, α-naphthol aralkyl type epoxy resins, biphenyl aralkyl phenol type epoxy resins, biphenyl type epoxy resins, triphenylmethane type epoxy resins, dicyclopentadiene type epoxy resins, alkylene glycol type epoxy resins, and various epoxy resins such as aliphatic cyclic epoxy resins.

[0082] Examples of polyglycidylamine compounds include diaminodiphenylmethane type epoxy resins, metaxylenediamine type epoxy resins, 1,3-bisaminomethylcyclohexane type epoxy resins, isocyanurate type epoxy resins, aniline type epoxy resins, hydantoin type epoxy resins, and aminophenol type epoxy resins.

[0083] Examples of polyglycidyl ester compounds include dimer acid type epoxy resins, hexahydrophthalic acid type epoxy resins, and trimellitic acid type epoxy resins.

[0084] Examples of the alicyclic general formula epoxy compounds include alicyclic epoxy resins such as Celloxide 2021 (manufactured by Daicel Chemical Industries, Ltd.).

[0085] Other modified epoxy resins include, for example, urethane-modified epoxy resins, oxazolidone ring-containing epoxy resins, epoxy-modified polybutadiene rubber derivatives, carboxyl-terminated butadiene nitrile rubber (CTBN)-modified epoxy resins, polyvinylarene polyoxides (e.g., divinylbenzene dioxide, trivinylnaphthalene trioxide, etc.), and phenoxy resins.

[0086] When the modified epoxy resin of the present invention and another epoxy resin are used in the resin composition of the present invention, the amount of the modified epoxy resin in the modified epoxy resin and all epoxy resin components is preferably 1 to 99 mass %, more preferably 50 mass % or more, and even more preferably 80 mass % or more. Furthermore, when the modified epoxy resin of the present invention is used together with another epoxy resin, the curing agent is preferably contained in an amount of 0.1 to 100 parts by mass, more preferably 0.5 to 80 parts by mass, and even more preferably 1 to 50 parts by mass, per 100 parts by mass of the total of the modified epoxy resin and the other epoxy resin.

[0087] The resin composition of the present invention may contain a solvent or reactive diluent to adjust the viscosity of the resin composition appropriately when handling the composition to form a coating film. In the resin composition of the present invention, the solvent or reactive diluent is used to ensure the ease of handling and workability when molding the resin composition, and there is no particular limit to the amount used. In the present invention, the term "solvent" and the aforementioned term "solvent" are used separately depending on the form of use, but the same or different substances may be used independently.

[0088] Examples of solvents that may be contained in the resin composition of the present invention include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, etc., esters such as ethyl acetate, ethers such as ethylene glycol monomethyl ether, amides such as N,N-dimethylformamide, N,N-dimethylacetamide, etc., alcohols such as methanol, ethanol, etc., alkanes such as hexane, cyclohexane, etc., aromatics such as toluene, xylene, etc. The above-mentioned solvents may be used alone, or two or more may be mixed in any combination and ratio.

[0089] Examples of reactive diluents include monofunctional glycidyl ethers such as allyl glycidyl ether, bifunctional glycidyl ethers such as propylene glycol diglycidyl ether, polyfunctional glycidyl ethers such as trimethylolpropane polyglycidyl ether, glycidyl esters, and glycidyl amines.

[0090] These solvents or reactive diluents are preferably used in an amount of 90% by mass or less as nonvolatile matter, and the appropriate type and amount are appropriately selected depending on the application. For example, for printed wiring board applications, polar solvents with a boiling point of 160°C or less, such as methyl ethyl ketone, acetone, and 1-methoxy-2-propanol, are preferred, and the amount used is preferably 40 to 80% by mass as nonvolatile matter. For adhesive film applications, for example, ketones, acetate esters, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone are preferred, and the amount used is preferably 30 to 60% by mass as nonvolatile matter.

[0091] If necessary, a curing accelerator or catalyst can be used in the resin composition of the present invention. Examples of the curing accelerator or catalyst include imidazole compounds, tertiary amines, phosphorus compounds such as phosphines, metal compounds, Lewis acids, and amine complex salts. These may be used alone or in combination of two or more.

[0092] The amount of curing accelerator or catalyst used may be selected appropriately depending on the intended use, but is preferably 0.01 to 15 parts by mass per 100 parts by mass of the epoxy resin component in the resin composition. It is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 8 parts by mass, even more preferably 0.1 to 5 parts by mass, and particularly preferably 0.1 to 1.0 part by mass. The use of a curing accelerator or catalyst can lower the curing temperature and shorten the curing time.

[0093] In order to improve the flame retardancy of the resulting cured product, various known flame retardants can be used in the resin composition of the present invention, as long as the reliability is not reduced. Usable flame retardants include, for example, halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, silicone-based flame retardants, inorganic flame retardants, and organic metal salt-based flame retardants. From an environmental perspective, halogen-free flame retardants are preferred, and phosphorus-based flame retardants are particularly preferred. These flame retardants may be used alone, or two or more of the same type of flame retardants may be used in combination, or different types of flame retardants may be used in combination.

[0094] The resin composition of the present invention may contain components other than those described above in order to further improve its functionality, such as fillers, thermoplastic resins, thermosetting resins, photocurable resins, ultraviolet inhibitors, antioxidants, coupling agents, plasticizers, fluxes, thixotropic agents, smoothing agents, colorants, pigments, dispersants, emulsifiers, elasticity reducing agents, release agents, antifoaming agents, and ion trapping agents.

[0095] Examples of fillers include inorganic fillers such as fused silica, crystalline silica, alumina, silicon nitride, boron nitride, aluminum nitride, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, boehmite, talc, mica, clay, calcium carbonate, magnesium carbonate, barium carbonate, zinc oxide, titanium oxide, magnesium oxide, magnesium silicate, calcium silicate, zirconium silicate, barium sulfate, and carbon; fibrous fillers such as carbon fiber, glass fiber, alumina fiber, silica alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aramid fiber, and ceramic fiber; and fine particle rubber.

[0096] The resin composition of the present invention may contain a thermoplastic resin. Examples of the thermoplastic resin include phenoxy resin, phosphorus-containing phenoxy resin, polyurethane resin, polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, ABS resin, AS resin, vinyl chloride resin, polyvinyl acetate resin, polymethyl methacrylate resin, polycarbonate resin, polyacetal resin, cyclic polyolefin resin, polyamide resin, thermoplastic polyimide resin, polyamideimide resin, polytetrafluoroethylene resin, polyetherimide resin, polyphenylene ether resin, modified polyphenylene ether resin, polyethersulfone resin, polysulfone resin, polyetheretherketone resin, polyphenylene sulfide resin, and polyvinyl formal resin. From the viewpoint of compatibility, phosphorus-containing phenoxy resin is preferred, and from the viewpoint of low dielectric properties, polyphenylene ether resin and modified polyphenylene ether resin are preferred.

[0097] Examples of other components include organic pigments such as quinacridone, azo, and phthalocyanine pigments, inorganic pigments such as titanium oxide, metal foil pigments, and anti-rust pigments, ultraviolet absorbers such as hindered amine, benzotriazole, and benzophenone, antioxidants such as hindered phenol, phosphorus, sulfur, and hydrazide, release agents such as stearic acid, palmitic acid, zinc stearate, and calcium stearate, and additives such as leveling agents, rheology control agents, pigment dispersants, anti-cracking agents, and anti-foaming agents. The amount of these other components added is preferably 0.01 to 20% by mass based on the total solid content of the resin composition.

[0098] The resin composition of the present invention can be obtained by uniformly mixing the above-mentioned components. Resin compositions containing a modified epoxy resin, a curing agent, and, if necessary, various other components can be easily cured using methods similar to those known in the art. This cured product exhibits excellent balance of low moisture absorption, dielectric properties, thermal conductivity, adhesion, and other properties, and exhibits good cured physical properties. "Curing" here refers to intentionally curing the resin composition using heat and / or light, and the degree of curing can be controlled depending on the desired physical properties and application. The degree of curing may be fully cured or semi-cured, and is not particularly limited; however, the reaction rate of the curing reaction between the epoxy groups and the curing agent is typically 5 to 95%.

[0099] The resin composition of the present invention can be cured to obtain a cured product by the same method as for known epoxy resin compositions. Methods for obtaining a cured product include those similar to those for known epoxy resin compositions, such as casting, injection, potting, dipping, drip coating, transfer molding, and compression molding, as well as laminating the resin in the form of a resin sheet, resin-coated copper foil, or prepreg, followed by heating and pressure curing to obtain a laminate. The curing temperature is typically in the range of 80 to 300°C, and the curing time is typically about 10 to 360 minutes. This heating is preferably carried out in two stages: a primary heating step at 80 to 180°C for 10 to 90 minutes, followed by a secondary heating step at 120 to 200°C for 60 to 150 minutes. Furthermore, for formulations whose glass transition temperature (Tg) exceeds the secondary heating temperature, a tertiary heating step at 150 to 280°C for 60 to 120 minutes is preferably carried out. Such secondary and tertiary heating steps can reduce poor curing. When producing a semi-cured resin product such as a resin sheet, a resin-coated copper foil, or a prepreg, the curing reaction of the resin composition is usually allowed to proceed to an extent that the shape can be maintained by heating, etc. When the resin composition contains a solvent, most of the solvent is usually removed by techniques such as heating, decompression, or air drying, but 5% by mass or less of the solvent may remain in the semi-cured resin product.

[0100] The prepreg obtained using the resin composition of the present invention will now be described. The sheet-like substrate can be, but is not limited to, a woven or nonwoven fabric made of inorganic fibers such as glass or organic fibers such as polyester, polyamine, polyacrylic, polyimide, Kevlar, or cellulose. The method for producing a prepreg from the resin composition of the present invention and the substrate is not particularly limited. For example, the substrate can be immersed in a resin varnish obtained by adjusting the viscosity of the resin composition with a solvent, and then heated and dried to semi-cure (B-stage) the resin composition. For example, the prepreg can be obtained by heating and drying at 100 to 200°C for 1 to 40 minutes. The resin content in the prepreg is preferably 30 to 80% by mass.

[0101] A method for producing a laminate using the prepreg or insulating adhesive sheet of the present invention will be described. When forming a laminate using prepreg, one or more prepregs are laminated, and metal foil is placed on one or both sides to form a laminate, which is then heated and pressed to form an integrated laminate. The metal foil used here can be a single, alloy, or composite metal foil of copper, aluminum, brass, nickel, or the like. The conditions for heating and pressing the laminate can be appropriately adjusted to the conditions under which the resin composition hardens. If the pressure applied is too low, air bubbles may remain inside the resulting laminate, potentially reducing its electrical properties. Therefore, it is desirable to apply pressure under conditions that satisfy moldability. For example, a temperature of 160 to 220°C and a pressure of 49 to 490 N / cm are used. 2 (5-50kgf / cm 2 ) and heating time can be set from 40 to 240 minutes.

[0102] Furthermore, a multilayer board can be produced using the single-layer laminate thus obtained as an inner layer material. In this case, a circuit is first formed on the laminate by an additive method, a subtractive method, or the like, and the surface of the formed circuit is then treated with an acid solution for blackening to obtain an inner layer material. An insulating layer is formed on one or both circuit-forming surfaces of this inner layer material using a prepreg or an insulating adhesive sheet, and a conductor layer is formed on the surface of the insulating layer to form a multilayer board.

[0103] When forming an insulating layer using an insulating adhesive sheet, a laminate is formed by placing an insulating adhesive sheet on the circuit-forming surfaces of multiple inner layer materials. Alternatively, a laminate is formed by placing an insulating adhesive sheet between the circuit-forming surfaces of the inner layer materials and metal foil. This laminate is then heated and pressurized to form an integral molding, thereby forming the cured insulating adhesive sheet as an insulating layer and forming a multilayer inner layer material. Alternatively, the inner layer material and the metal foil serving as the conductor layer are combined to form the cured insulating adhesive sheet as an insulating layer. Here, the metal foil can be the same as that used in the laminate used as the inner layer material. Furthermore, the hot and pressure molding can be carried out under the same conditions as those for molding the inner layer material. When forming an insulating layer by applying a resin composition to a laminate, the resin for forming the circuit on the outermost layer of the inner layer material is preferably applied to a thickness of 5 to 100 μm with the above-mentioned resin composition, and then heated and dried at 100 to 200°C for 1 to 90 minutes to form a sheet. This is generally formed by a method called a casting method. The thickness after drying is preferably formed to 5 to 80 μm. A printed wiring board can be formed by further forming via holes and circuits on the surface of the multilayer laminate thus formed by an additive method or a subtractive method. Furthermore, by repeating the above process using this printed wiring board as an inner layer material, it is possible to form a multi-layer laminate.

[0104] When forming an insulating layer using prepreg, one or more prepreg sheets are placed on the circuit-forming surface of the inner layer material, and a metal foil is placed on the outside of the prepreg to form a laminate. This laminate is then heated and pressurized to form an integral molding, whereby the cured prepreg is formed as an insulating layer and the outer metal foil is formed as a conductor layer. Here, the metal foil may be the same as that used in the laminate used as the inner layer material. The hot-press molding can be carried out under the same conditions as those for molding the inner layer material. The surface of the multilayer laminate thus molded can be further subjected to via hole formation and circuit formation by an additive method or a subtractive method to mold a printed wiring board. Furthermore, by repeating the above process using this printed wiring board as an inner layer material, it is possible to form a multi-layer board with even more layers.

[0105] The cured product and laminate for electric / electronic circuits obtained from the resin composition of the present invention have excellent dielectric properties and thermal conductivity. [Example]

[0106] The present invention will be explained in more detail below based on examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, parts represent "parts by mass" and % represents "% by mass." Analytical and measurement methods are shown below. Furthermore, the unit of various equivalents is "g / eq."

[0107] (1) Number average molecular weight (Mn): The solubility was determined by GPC measurement. Specifically, a Tosoh HLC8320 GPC main body equipped with columns (TSKgel SuperH-H, SuperH2000, SuperHM-H, SuperHM-H, all Tosoh) in series was used, and the column temperature was set to 40°C. Tetrahydrofuran (THF) was used as the eluent at a flow rate of 1.0 mL / min, and a refractive index detector was used. 0.1 g of solids were dissolved in 10 mL of THF and filtered through a 0.45 μm microfilter, resulting in 50 μL of the sample. Data processing was performed using a Tosoh GPC8020 Model II version 6.00.

[0108] (2) IR (infrared absorption spectrum): A Fourier transform infrared spectrophotometer (Perkin Elmer Precisely, Spectrum One FT-IR Spectrometer 1760X) was used, and the cell was filled with sodium chloride. The sample dissolved in chloroform was applied to the cell, dried, and then measured at a wavenumber of 450 to 4000 cm. -1 The transmittance was measured.

[0109] (3) Epoxy equivalent: Measurements were carried out in accordance with JIS K7236. Specifically, a potentiometric titrator was used, chloroform was used as the solvent, tetraethylammonium bromide acetate solution was added, and a 0.1 mol / L perchloric acid-acetic acid solution was used. For solvent-diluted products (resin varnishes), the solid content was calculated from the nonvolatile content.

[0110] (4) Non-volatile content (solid content): Measurement was performed in accordance with JIS K7235. The drying temperature was 200°C and the drying time was 60 minutes.

[0111] (5) Liquidity: The solution viscosity was measured at 25°C using a B-type rotational viscometer (TVB-10M, manufactured by Toki Sangyo Co., Ltd.) and evaluated.

[0112] (6) Solubility: The modified epoxy resin was made into a resin varnish with a resin content of 30% using cyclohexanone, and the same amount of bisphenol A type epoxy resin (YD-128, manufactured by Nippon Steel Chemical & Material Co., Ltd.) was added. The mixture was shaken in a shaker for 1 hour, and then left to stand in a thermostatic bath at 25°C for 24 hours, after which the condition was visually inspected. The evaluation is as follows: 〇: Uniform and transparent ×: Cloudy or separated

[0113] (7) Thermal conductivity: The thermal conductivity was measured by the transient hot wire method using a thermal conductivity meter (NETZSCH, LFA447 model).

[0114] (8) Dielectric properties: The dielectric loss tangent was evaluated by measuring at 1 GHz using the capacitance method. Specifically, measurements were carried out using a material analyzer (manufactured by Agilent Technologies) in accordance with the IPC-TM-650 2.5.5.9 standard, under conditions of room temperature of 23°C and humidity of 50% RH, using a 30 mm square x 1 mm thick test piece.

[0115] The abbreviations used in the examples and comparative examples are as follows:

[0116] A1: Hydroquinone-type epoxy resin (Nippon Steel Chemical & Material Co., Ltd., ZX-1027, epoxy equivalent 130, m≒0.17) [ka] A2: Naphthalene-type epoxy resin (DIC Corporation, Epicron HP4032D, epoxy equivalent 142, m≒0.04) [ka]

[0117] B1: 1,4-diacetoxybenzene (Tokyo Chemical Industry Co., Ltd., active equivalent weight 97) [ka] B2: 2,6-diacetoxynaphthalene (Tokyo Chemical Industry Co., Ltd., active equivalent: 122) [ka] B3: 2,2-bis(4-acetoxyphenyl)propane (Tokyo Chemical Industry Co., Ltd., active equivalent: 156) [ka] Here, the active equivalent refers to the equivalent of an active ester group.

[0118] [Phenol compounds] C1: 2,6-naphthalenediol (Tokyo Chemical Industry Co., Ltd., hydroxyl equivalent: 80) [ka]

[0119] [catalyst] D1: 4-Dimethylaminopyridine (Fujifilm Wako Pure Chemical Industries, Ltd.) D2: 2-ethyl-4-methylimidazole (Curesol 2E4MZ, manufactured by Shikoku Chemicals Corporation)

[0120] [Hardening agent] H1: Phenol novolac resin (manufactured by Aica Kogyo Co., Ltd., Shounol BRG-557, hydroxyl group equivalent: 105) H2: 2-ethyl-4-methylimidazole (Curesol 2E4MZ, manufactured by Shikoku Chemicals Corporation)

[0121] [Solvents] S1: Cyclohexanone

[0122] Example 1 A glass reaction vessel equipped with a stirrer, thermometer, nitrogen gas inlet, condenser, and dropping device was charged with 100.0 parts of A1, 24.9 parts of B1, and 54 parts of S1 at room temperature. The mixture was heated to 130°C while stirring and nitrogen gas was passed through. 0.1 parts of D1 was added, and the mixture was heated to 145°C and reacted for 3 hours at a temperature range of 145 to 150°C. 238 parts of S1 was used as a dilution solvent for dilution and mixing, yielding a modified epoxy resin (R1) with a non-volatile content (solid content) of 30%.

[0123] Examples 2 to 8, Comparative Examples 1 to 2 A modified epoxy resin was obtained by the same procedure as in Example 1, using the amounts (parts) of each raw material shown in Table 1. The epoxy equivalent, Mn, nonvolatile content, flowability, and solubility of the obtained modified epoxy resin were measured. The results are shown in Table 1. In the table, "molar ratio" represents the molar ratio of the difunctional epoxy resin to the diester compound and the difunctional phenol compound, "Xa group content" represents the content (mol %) of Xa groups in all X in general formula (1), and "acylation rate" represents the content (mol %) of acyl groups in all Z in general formula (1).

[0124] [Table 1]

[0125] Example 9 100 parts of modified epoxy resin varnish R1 (30 parts solids), 12.1 parts of curing agent H1, and 0.3 parts of H2 were blended and dissolved in a mixed solvent prepared with MEK, propylene glycol monomethyl ether, and N,N-dimethylformamide to obtain a resin composition varnish. The resulting resin composition varnish was impregnated into glass cloth (Nitto Boseki Co., Ltd., WEA 7628 XS13, 0.18 mm thick). The impregnated glass cloth was dried in a hot air circulating oven at 150 °C for 9 minutes to obtain a prepreg.

[0126] The resulting prepreg was loosened and sieved to a powder form (100 mesh pass). The resulting prepreg powder was placed in a fluororesin mold and vacuum pressed at 2 MPa under the following temperature conditions: 130°C for 15 minutes and 190°C for 80 minutes to obtain a 1.0 mm thick test piece for evaluating dielectric properties and thermal conductivity. The results are shown in Table 2.

[0127] Examples 10 to 12 and Comparative Examples 3 to 4 Test pieces for evaluating dielectric properties and thermal conductivity were obtained by compounding the ingredients in the amounts (parts) shown in Table 2 and carrying out the same operations as in Example 9. Tests similar to those in Example 9 were carried out, and the results are shown in Table 2.

[0128] [Table 2]

[0129] As can be seen from Table 1, the modified epoxy resin of the present invention has excellent solubility and flowability, and as can be seen from Table 2, the cured product made from the modified epoxy resin composition of the present invention has excellent dielectric properties and thermal conductivity. [Industrial Applicability]

[0130] The modified epoxy resin and resin composition of the present invention are applicable to various fields, such as adhesives, paints, civil engineering and building materials, insulating materials for electric and electronic components, etc. They are particularly useful as insulating casting materials, laminate materials, sealing materials, etc. in the electric and electronic fields, and are particularly suitable for multilayer printed wiring boards, laminates for electric and electronic circuits such as capacitors, adhesives such as film adhesives and liquid adhesives, semiconductor sealing materials, underfill materials, interchip fill materials for 3D-LSI, insulating sheets, prepregs, heat dissipation substrates, etc.

Claims

1. A modified epoxy resin represented by the following general formula (1) and having an epoxy equivalent of 200 g / eq. or more and less than 5,000 g / eq.: 【Chemistry 1】 In the formula, X is independently a divalent group, 70 mol % or more of which are monocyclic or condensed polycyclic aromatic hydrocarbon groups having 6 to 20 carbon atoms selected from the group consisting of a benzene ring group, a naphthalene ring group, an anthracene ring group, or a phenanthrene ring group, and these monocyclic or condensed polycyclic aromatic hydrocarbon groups may have a substituent. Y is independently a hydrogen atom, an acyl group having 2 to 20 carbon atoms, or a glycidyl group. Z is an acyl group having 2 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more are acyl groups. n is the average number of repeating groups and is greater than 0 and not more than 30.

2. 2. The modified epoxy resin according to claim 1, which has a number average molecular weight of 150 to 10,000.

3. A resin composition comprising the modified epoxy resin according to claim 1 and a curing agent.

4. 4. The resin composition according to claim 3, comprising 0.1 to 100 parts by mass of a curing agent per 100 parts by mass of the modified epoxy resin.

5. A resin composition comprising the modified epoxy resin according to claim 1, another epoxy resin, and a curing agent, wherein the mass ratio of the modified epoxy resin to the epoxy resin is 99 / 1 to 1 / 99.

6. 6. The resin composition according to claim 5, comprising 0.1 to 100 parts by mass of a curing agent per 100 parts by mass of the modified epoxy resin and the other epoxy resin.

7. 4. The resin composition according to claim 3, wherein the curing agent is at least one selected from the group consisting of acrylic ester resins, melamine resins, urea resins, phenolic resins, acid anhydrides, amine compounds, imidazole compounds, amide compounds, cationic polymerization initiators, organic phosphines, polyisocyanate compounds, blocked isocyanate compounds, carbodiimide compounds, and active ester curing agents.

8. A cured product obtained by curing the resin composition according to any one of claims 3 to 7.

9. A laminate for electric / electronic circuits, which is obtained by using the resin composition according to any one of claims 3 to 7.

10. 2. The method for producing a modified epoxy resin according to claim 1, wherein the modified epoxy resin is obtained by reacting a bifunctional epoxy resin represented by the following general formula (2) with a compound represented by the following general formula (3): 【Chemistry 2】 Here, X １ , X ２ are independently divalent groups, and X １ and X ２ of the total are monocyclic or fused polycyclic aromatic hydrocarbon groups having 6 to 20 carbon atoms selected from the group consisting of a benzene ring group, a naphthalene ring group, an anthracene ring group, and a phenanthrene ring group, and these monocyclic or fused polycyclic aromatic hydrocarbon groups may have a substituent. G is a glycidyl group, and Q is independently an acyl group having 2 to 20 carbon atoms or a hydrogen atom, and 5 mol % or more are acyl groups. m is the average number of repeating units and is from 0 to 6.

11. 11. The method for producing a modified epoxy resin according to claim 10, wherein the compound represented by general formula (3) is a compound in which at least one Q is an acyl group, or a mixture of a compound in which at least one Q is an acyl group and a compound in which both Qs are hydrogen atoms.

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