WO2023162693A1 - Epoxy resin, polyhydric hydroxy resin, epoxy resin composition, cured epoxy resin product, and method for producing polyhydric hydroxy resin - Google Patents

Abstract

Provided are: an epoxy resin which is useful as an insulating material for electrical/electronic components, exhibits excellent handleability as a solid at ordinary temperatures, has a low viscosity at the time of molding, and exhibits excellent solvent solubility; a polyhydric hydroxy resin; an epoxy resin composition obtained using these; and a cured product which is obtained therefrom and is excellent in terms of high thermal conductivity and high heat resistance. The epoxy resin is represented by general formula (1). (Here, A denotes an aromatic group comprising a benzene ring, biphenyl or a naphthalene ring; G denotes a glycidyl group; R moieties each independently denote a hydrocarbon group having 1-10 carbon atoms; and n denotes a number from 3 to 10.)

Description

Epoxy resin, polyhydroxy resin, epoxy resin composition, cured epoxy resin, and method for producing polyhydroxy resin

TECHNICAL FIELD The present invention relates to epoxy resins, polyhydroxy resins, epoxy resin compositions, cured epoxy resins, and methods for producing polyhydroxy resins, and more particularly to electrical and electronic parts such as semiconductor encapsulation, laminates, and heat dissipation substrates. The present invention relates to an epoxy resin, a polyhydric hydroxy resin, and an epoxy resin composition which are useful as insulating materials for industrial applications and which are solid at room temperature and have excellent handleability, low viscosity during molding, and excellent solvent solubility. The present invention also relates to epoxy resin cured products obtained by curing using them and having excellent high thermal conductivity, heat resistance and low thermal expansion. Furthermore, it relates to a method for producing the polyhydric hydroxy resin.

Epoxy resins have been used in a wide range of industrial applications, but the required performance has become more sophisticated in recent years. In the electric/electronics field and the power electronics field, where electronic circuits are becoming more dense and higher in frequency, the amount of heat generated from electronic circuits is increasing. It's becoming Conventionally, this heat dissipation has been covered by the thermal conductivity of the filler, but in order to achieve higher integration, it has become necessary to improve the thermal conductivity of the matrix epoxy resin itself.

As an epoxy resin composition excellent in high thermal conductivity, one using an epoxy resin having a mesogenic structure is known. It discloses an epoxy resin composition as a component, which is excellent in stability and strength at high temperatures and can be used in a wide range of fields such as adhesion, casting, sealing, molding and lamination. Further, Patent Document 2 discloses an epoxy compound having two mesogenic structures linked by a bent chain in its molecule. Furthermore, Patent Document 3 discloses a resin composition containing an epoxy compound having a mesogenic group.

However, epoxy resins with such a mesogenic structure have a high melting point, and when mixed, the high-melting-point component is difficult to dissolve and remains undissolved, resulting in reduced curability and heat resistance. Also, a high temperature was required to uniformly mix such an epoxy resin with a curing agent. At high temperatures, the curing reaction of the epoxy resin proceeds rapidly and the gelling time is shortened. When a soluble third component is added to compensate for this drawback, the melting point of the resin is lowered to facilitate uniform mixing, but the resulting cured product has a reduced thermal conductivity.

As a high thermal conductivity resin that can be melt-mixed, Patent Document 4 discloses an epoxy resin obtained by epoxidizing a mixture of hydroquinone and 4,4'-dihydroxybiphenyl, and Patent Document 5 discloses 4,4'-dihydroxy Epoxy resins are disclosed which are epoxidized mixtures of diphenylmethane and 4,4'-dihydroxybiphenyl. However, these resins are poorly soluble in solvents and have limited applications. Patent Document 6 discloses an epoxy resin composition having a diphenyl ether structure, but the curing agent is limited, and general-purpose curing agents such as phenol novolak are insufficient in thermal conductivity and heat resistance. .
On the other hand, calixarene-based compounds, which are cyclic compounds, are known as structures exhibiting strong crystallinity, but they have the problem of low solubility in solvents. In addition, although Patent Document 7 discloses a resin composition obtained by mixing a resorcinol-aldehyde polycondensate and an epoxy resin, it is limited to use as a curing agent, and the heat resistance of the cured product is 210°C or less. Ta. Patent Document 8 discloses a resin containing a naphthalene cyclic compound, but the content of the cyclic compound is low and the effect of thermal stability is not sufficient.

JP-A-7-90052 JP-A-9-118673 JP-A-11-323162 WO2009/110424 JP 2010-43245 A JP 2012-17405 A JP-A-2001-106868 Japanese Unexamined Patent Application Publication No. 2012-201798

Accordingly, an object of the present invention is to solve the above problems, and to provide excellent handleability as a solid at normal temperature, which is useful as an insulating material for electric and electronic parts such as highly reliable semiconductor encapsulation, laminates, and heat dissipation substrates. To provide an epoxy resin, a polyhydric hydroxy resin, and an epoxy resin composition using these, which have low viscosity during molding and excellent solvent solubility, and which have excellent high thermal conductivity and high heat resistance obtained therefrom. An object of the present invention is to provide a cured product, and to provide a method for producing a polyhydric hydroxy resin as a raw material thereof.

The inventors of the present invention have found through intensive studies that an epoxy resin composition using a specific epoxy resin and/or a polyhydroxy resin can solve the above problems, and that the cured product thereof has good thermal conductivity and heat resistance. The present invention was completed after discovering that it was excellent.

（ただし、Ａはベンゼン環、ビフェニルまたはナフタレン環からなる芳香族基を示し、Ｇはグリシジル基、Ｒはそれぞれ独立して、炭素数１～１０の炭化水素基を示し、ｎは３～１０の数を示す。） That is, the present invention relates to an epoxy resin represented by the following general formula (1).

(where A represents an aromatic group consisting of a benzene ring, biphenyl or naphthalene ring, G represents a glycidyl group, R each independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents 3 to 10 number.)

（ただし、Ｇはグリシジル基、Ｒはそれぞれ独立して、炭素数１～１０の炭化水素基を示し、ｎは３～１０の数を示す。） The epoxy resin of the present invention is preferably an epoxy resin represented by the following general formula (2).

(However, G is a glycidyl group, R each independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10.)

（ただし、Ｒはそれぞれ独立して、炭素数１～１０の炭化水素基を示し、ｎは３～１０の数を示す。） The present invention also relates to a polyhydric hydroxy resin represented by the following general formula (3).

(However, each R independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10.)

Further, the present invention is an epoxy resin composition characterized by comprising the above epoxy resin as an essential component and/or comprising the above polyhydric hydroxy resin as an essential component as a curing agent, and this epoxy It is an epoxy resin cured product obtained by curing a resin composition.

（ただし、Ｒは炭素数１～１０の炭化水素基を示す。）

（ただし、Ｒは炭素数１～１０の炭化水素基を示す。） The present invention also relates to a method for producing a polyhydric hydroxy resin represented by the general formula (3), wherein hydroquinone represented by the following formula (4) and hydroquinone represented by the following formula (5) and / or (6) The present invention relates to a method for producing a polyhydric hydroxy resin obtained by reacting an aldehyde with a polyhydric hydroxy resin in the presence of a strong acid.

(However, R represents a hydrocarbon group having 1 to 10 carbon atoms.)

(However, R represents a hydrocarbon group having 1 to 10 carbon atoms.)

The epoxy resin of the present invention and the polyhydric hydroxy resin as a curing agent have good melt-kneadability at 100° C. or less and excellent solvent solubility, so they can be used for applications such as lamination, molding, casting, and adhesion. It is suitable for the epoxy resin composition and its cured product. The cured product has excellent heat resistance, thermal decomposition stability, and thermal conductivity, and is therefore suitable for sealing electric/electronic parts, circuit board materials, and the like.

1 is an FD-MS spectrum of the phenolic compound (polyhydric hydroxy resin) obtained in Example 1. FIG. 1 is a GPC chart of a phenolic compound (polyhydric hydroxy resin) obtained in Example 1. FIG. 2 is an FD-MS spectrum of the epoxy resin obtained in Example 2. FIG. 2 is a GPC chart of the epoxy resin obtained in Example 2. FIG.

The present invention will be described in detail below.

The epoxy resin of the present invention is represented by the above general formula (1), where A represents an aromatic group consisting of a benzene ring, biphenyl or naphthalene ring. A may be a mixture of two or more. G represents a glycidyl group. Each R independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10. In addition, as described above as "independently", the epoxy resin of the formula (1) of the present invention can be a mixture of structures in which A differs. n is the number of repetitions (number average) and is a number from 3 to 10. Preferred are mixtures of components with different values of n.

（ただし、Ａはベンゼン環、ビフェニルまたはナフタレン環からなる芳香族基を示し、Ｇはグリシジル基、Ｒはそれぞれ独立して、炭素数１～１０の炭化水素基を示し、ｍは０～１５の数を示す。） The epoxy resin of the present invention may be a mixture with a linear epoxy resin represented by the following general formula (7). Preferably, the linear content is 60% or less, more preferably 40% or less. When there are many linear components, the heat resistance tends to decrease.

(where A represents an aromatic group consisting of a benzene ring, biphenyl or naphthalene ring, G represents a glycidyl group, R each independently represents a hydrocarbon group having 1 to 10 carbon atoms, m represents 0 to 15 number.)

In the above general formula (1) or (7), each R independently represents a hydrocarbon group having 1 to 10 carbon atoms. R may be a mixture of hydrocarbons with different carbon numbers. In some cases, R may contain only a chain or an aromatic. In the case of only a chain, the larger the number of carbon atoms, the better the solvent solubility, but the heat resistance tends to decrease. In particular, for heat resistance, R is preferably a hydrocarbon group having 7 or less carbon atoms. More preferably, it has 1 to 4 carbon atoms. When R contains an aromatic group, the heat resistance is excellent, but the solvent solubility tends to decrease.

The epoxy resin of the present invention preferably has a structure represented by the above general formula (2). The substitution position of the glycidyl group is preferably the para position. In the case of the resorcinol type, which is in the meta position, the glycidyl groups of the cyclic compound are close to each other, and it may be difficult to control the reaction due to the steric structure. On the other hand, in the case of the para-position hydroquinone type, it is possible to obtain a stable structure capable of controlling the reaction, and a cured product having high heat resistance can be obtained. Further, the structure of A in the general formula is preferably a biphenyl or naphthalene ring from the viewpoint of heat resistance, and preferably a benzene ring from the viewpoint of solvent solubility.

The softening point of the epoxy resin of the present invention or a mixture of this and the epoxy resin represented by the above general formula (7), which may optionally be included, is preferably 130°C or less. If the temperature is higher than 130°C, the melt-kneadability is lowered, and if it has crystallinity, the solvent solubility is also lowered.

（ただし、Ａはベンゼン環、ビフェニル、またはナフタレン環からなる芳香族基を示し、Ｒはそれぞれ独立して、炭素数１～１０の炭化水素基を示し、ｎは３～１０の数を示す。） The method for producing the epoxy resin of the present invention is not particularly limited. This reaction can be carried out in the same manner as a normal epoxidation reaction.

(where A represents an aromatic group consisting of a benzene ring, biphenyl or naphthalene ring, each R independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10. )

As described above, the phenolic compound of formula (8) is preferably of the hydroquinone type in which the hydroxyl group is at the para position. More preferably, A is a benzene ring as in the above formula (3).

The reaction between the phenolic compound of formula (8) and epichlorohydrin can be carried out, for example, by dissolving the phenolic compound in an excess of epichlorohydrin and then reacting it in the presence of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide. A method of reacting at 150° C., preferably at 60 to 100° C. for 1 to 10 hours can be mentioned. At this time, the amount of the alkali metal hydroxide used is in the range of 0.8 to 2.0 mol, preferably 0.9 to 1.5 mol, per 1 mol of the hydroxyl group in the phenolic compound. . Epichlorohydrin is used in an excess amount relative to the hydroxyl groups in the phenolic compound, usually 1.5 to 15 mol per 1 mol of hydroxyl groups in the phenolic compound. After completion of the reaction, excess epichlorohydrin is distilled off, the residue is dissolved in a solvent such as toluene or methyl isobutyl ketone, filtered, washed with water to remove inorganic salts, and the solvent is distilled off to obtain the desired epoxy. resin can be obtained.

（但し、Ａ、Ｒ、ｍは上記式（７）と同義である。） When a phenolic compound containing a linear polyhydric hydroxy resin represented by the general formula (9) is used as a raw material, the epoxy resin of the present invention is a mixture with the epoxy resin represented by the general formula (7). is obtained as

(However, A, R, and m are synonymous with the above formula (7).)

The purity of the epoxy resin of the present invention, particularly the amount of hydrolyzable chlorine, should be less from the viewpoint of improving the reliability of electronic components to which it is applied. Although not particularly limited, it is preferably 1000 ppm or less, more preferably 500 ppm or less. In addition, the hydrolyzable chlorine referred to in the present invention refers to the value measured by the following method. That is, after dissolving 0.5 g of the sample in 30 ml of dioxane, 10 ml of 1N-KOH was added and the mixture was boiled and refluxed for 30 minutes, cooled to room temperature, further 100 ml of 80% acetone water was added, and a potential difference was obtained with an aqueous 0.002N- _AgNO3 solution. It is a value obtained by titration.

Here, the phenolic compound represented by formula (8) is not limited, but examples include hydroquinone, catechol, resorcinol, 4,4'-biphenol, 2,2'-biphenol, 1,2-dihydroxynaphthalene. , 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, For bifunctional phenolic compounds such as 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, and 2,8-dihydroxynaphthalene, acetaldehyde and propionaldehyde , n-butyraldehyde, paraldehyde, benzaldehyde, 4-methylbenzaldehyde, 3-methylbenzaldehyde, 2-methylbenzaldehyde, 4-ethylbenzaldehyde, 2,4-dimethylbenzaldehyde, 3,4-dimethylbenzaldehyde, 4-isopropylbenzaldehyde, It can be obtained by a method of condensing aldehydes such as 4-tert-butylbenzaldehyde in the presence of an organic or inorganic acid (for example, Aldrichimica Acta, Vol. 28, No. 1, 1995, Pages 3 to 9, etc. You can refer to the described method).

A plurality of mixtures may be used as aldehydes, but acetaldehyde or trimer paraldehyde in which R is a methyl group should account for 50% or more of all aldehydes in molar ratio in terms of acetaldehyde. It is preferred in terms of properties and solvent solubility.

The molar ratio in reacting the phenolic compound and the condensing agent for the aldehydes is not particularly limited, but the aldehydes are preferably 0.3 to 1.2 mol, preferably 0.5, per 1 mol of the phenolic compound. ~1.0 mol is more preferred. When the aldehydes are multimer aldehydes, it is preferable that the molar amount of the multimer multiplied by the degree of polymerization of the multimer satisfies the above molar number range. For example, 1 mol of paraldehyde is 3 mol in terms of acetaldehyde, so when using paraldehyde, it is preferable to use 0.1 to 0.4 mol with respect to 1 mol of the phenolic compound. Become.

The catalyst is not particularly limited as long as the reaction proceeds, and known catalyst species such as inorganic acids and organic acids can be used. Specific examples include hydrobromic acid, hydrochloric acid, sulfuric acid, phosphoric acid, oxalic acid, trifluoroacetic acid, p-toluenesulfonic acid, methanesulfonic acid, and boron trifluoride. Hydrochloric acid and sulfuric acid, which are strong acids, are particularly preferred.

The amount of the catalyst is preferably 0.1-30.0% by mass, more preferably 1.0-10.0% by mass, relative to the phenolic compound. If the amount of catalyst is less than the lower limit of the range, the reaction rate tends to be slow, and if it exceeds the upper limit, the reaction tends to be difficult to control.

The reaction solvent is not particularly limited, but water or a hydrocarbon solvent is preferable. Examples of hydrocarbon solvents include normal hexane, cyclohexane, and toluene. The reaction solvent may be used singly or in combination of two or more.

The reaction temperature between the phenolic compound and the aldehydes is preferably 20°C to 150°C, more preferably 60°C to 110°C. If the reaction temperature is less than the lower limit of the above range, the reaction tends to be slow, and if it is higher than the upper limit, the reaction tends to be difficult to control.

The reaction product precipitated by the reaction between the phenolic compound and the aldehydes can be recovered by a known solid-liquid separation treatment such as filtration. After recovery, washing with water, purification, recrystallization, etc. may be performed as necessary.

Among the phenolic compounds represented by the above formula (8), in order to produce the polyhydric hydroxy resin represented by the above general formula (3), for hydroquinone represented by the above formula (4), It is preferable to react the aldehydes represented by the general formulas (5) and/or (6). More preferably, acetaldehyde and/or paraaldehyde in which R is a methyl group in formulas (5) and/or (6) are used, and the conditions are as described above.

In the epoxy resin of the present invention, in addition to the epoxy resin of formula (1) used as an essential component or the optional epoxy resin of formula (7), other epoxy resin components having two or more epoxy groups in the molecule may be used. You may use an epoxy resin together. Examples include bisphenol A, bisphenol F, 3,3′,5,5′-tetramethyl-4,4′-dihydroxydiphenylmethane, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, fluorene bisphenol, 4,4'-biphenol, 3,3',5,5'-tetramethyl-4,4'-dihydroxybiphenyl, 2,2'-biphenol, resorcin, catechol , t-butyl catechol, t-butyl hydroquinone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7- Dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxy Naphthalene, allylated or polyallylated dihydroxynaphthalene, allylated bisphenol A, allylated bisphenol F, dihydric phenols such as allylated phenol novolak, or phenol novolak, bisphenol A novolak, o-cresol novolak, m- cresol novolak, p-cresol novolak, xylenol novolak, poly-p-hydroxystyrene, tris-(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, fluoroglycinol, pyrogallol , t-butyl pyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, phenol aralkyl resin, naphthol aralkyl resin, dicyclopentadiene-based resin, etc. There are glycidyl etherified products derived from the above phenols or halogenated bisphenols such as tetrabromobisphenol A. These epoxy resins can be used singly or in combination of two or more.

The epoxy resin composition of the present invention contains an epoxy resin and a curing agent, and may contain other optional components described later. At that time, the epoxy resin composition of the present invention uses the epoxy resin represented by the above general formula (1) and/or the polyhydroxy resin represented by the above general formula (8) as a curing agent. is preferable, and it is more preferable to use the general formula (3).

In the case of an epoxy resin composition using an epoxy resin represented by general formula (1), the proportion of the epoxy resin represented by formula (1) is preferably 30 wt% or more, more preferably 50 wt% of the total epoxy resin. That's it. If the amount is less than this, the effect of improving physical properties such as heat resistance may be reduced when the cured product is obtained.

In the case of the epoxy resin composition using the epoxy resin represented by the general formula (1), as the curing agent, all those generally known as curing agents for epoxy resins can be used, such as dicyandiamide, acid anhydrides, poly There are hydric phenols, aromatic and aliphatic amines, and the like. Among these, polyhydric phenols are preferably used as a curing agent in fields such as semiconductor encapsulants that require high electrical insulation. Moreover, it is preferable to use dihydric phenols as a hardening|curing agent excellent in high thermal conductivity. Specific examples of the curing agent are shown below.

Examples of polyhydric phenols include dihydric phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcinol, naphthalene diol, or , tris-(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, phenol novolak, o-cresol novolak, naphthol novolak, polyvinylphenol, etc. There are phenols. Furthermore, dihydric phenols such as phenols, naphthols, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcinol, and naphthalenediol, There are polyhydric phenolic compounds synthesized with condensing agents such as formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde and p-xylylene glycol.

Examples of acid anhydride curing agents include phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl himic anhydride, dodecynylsuccinic anhydride, nadic anhydride, and trimellitic anhydride.

Amine curing agents include aromatic amines such as 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylsulfone, m-phenylenediamine and p-xylylenediamine; There are aliphatic amines such as ethylenediamine, hexamethylenediamine, diethylenetriamine and triethylenetetramine.

One or a mixture of two or more of these curing agents can be used in the epoxy resin composition.

The blending ratio of the epoxy resin and the curing agent is preferably in the range of 0.8 to 1.5 in terms of the equivalent ratio of the epoxy groups to the functional groups in the curing agent. Outside this range, unreacted epoxy groups or functional groups in the curing agent remain even after curing, and the reliability of the sealing function is lowered, which is not preferable.

As the epoxy resin composition of the present invention, if the polyhydroxy resin represented by the above general formula (8) (preferably general formula (3)) is used as a curing agent, the epoxy resin is the above formula ( It is not limited to 1). As the epoxy resin in that case, all of the epoxy resins described above can be used without limitation, but epoxy resins having a divalent rigid structure are preferable in terms of heat resistance and thermal conductivity. -dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl ether, 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcin, catechol , 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, glycidyl ether compounds derived from 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene and 2,8-dihydroxynaphthalene; and more preferably glycidyl ether compounds derived from 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl ether, 4,4'-biphenol and hydroquinone. At that time, the mixing ratio of the polyhydric hydroxy resin represented by the general formula (8) (preferably general formula (3)) as a curing agent is preferably 20 wt% or more of the total curing agent, and more preferably. is 50 wt% or more. If the amount is less than this, the effect of improving physical properties such as heat resistance may be reduced when the cured product is obtained.

In the epoxy resin composition of the present invention, oligomers or polymer compounds such as polyester, polyamide, polyimide, polyether, polyurethane, petroleum resin, indene resin, indene-cumarone resin, phenoxy resin, etc. may be used as other modifiers. It may be blended as appropriate. The amount added is usually in the range of 1 to 30 parts by weight with respect to 100 parts by weight of the total resin components.

Additives such as inorganic fillers, pigments, flame retardants, thixotropic agents, coupling agents, fluidity improvers and the like can be added to the epoxy resin composition of the present invention. Examples of inorganic fillers include spherical or crushed fused silica, silica powder such as crystalline silica, alumina powder, glass powder, mica, talc, calcium carbonate, alumina, and hydrated alumina. When used as a sealing material, the blending amount is preferably 70% by weight or more, more preferably 80% by weight or more.

Pigments include organic or inorganic extender pigments and scaly pigments. Examples of the thixotropic agent include silicon-based, castor oil-based, aliphatic amide wax, oxidized polyethylene wax, and organic bentonite-based agents.

A curing accelerator can be used in the epoxy resin composition of the present invention as necessary. Examples include amines, imidazoles, organic phosphines, Lewis acids, etc. Specific examples include 1,8-diazabicyclo(5,4,0)undecene-7, triethylenediamine, benzyldimethylamine, tri Tertiary amines such as ethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2- imidazoles such as heptadecyl imidazole; organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine; tetraphenylphosphonium/tetraphenylborate; tetraphenylphosphonium/ethyltriphenylborate; Tetra-substituted phosphonium/tetra-substituted borate such as butylphosphonium/tetrabutylborate, tetraphenylboron salts such as 2-ethyl-4-methylimidazole/tetraphenylborate, and N-methylmorpholine/tetraphenylborate. The amount added is usually in the range of 0.01 to 5 parts by weight per 100 parts by weight of the total resin components.

Furthermore, if necessary, the epoxy resin composition of the present invention may contain a releasing agent such as carnauba wax or OP wax, a coupling agent such as γ-glycidoxypropyltrimethoxysilane, a coloring agent such as carbon black, Flame retardants such as antimony oxide, stress reducing agents such as silicone oil, and lubricants such as calcium stearate can be used.

The epoxy resin composition of the present invention is made into a varnish state by dissolving an organic solvent, impregnated with a fibrous material such as a glass cloth, an aramid nonwoven fabric, a polyester nonwoven fabric such as a liquid crystal polymer, and the like, and then the solvent is removed to obtain a prepreg. can be In some cases, a laminate can be obtained by coating a sheet-like material such as a copper foil, a stainless steel foil, a polyimide film, a polyester film, or the like.

By curing the epoxy resin composition of the present invention by heating, the resin cured product of the present invention can be obtained. This cured product can be obtained by molding the epoxy resin composition by a method such as casting, compression molding, or transfer molding. The temperature at this time is usually in the range of 120 to 220°C. As for heat resistance, it exhibits a Tg of 250°C or higher, and it is possible to develop a Tg of 300°C or higher. Compared with the limit of Tg of ordinary epoxy resin cured products of about 250° C., the cured product of the present invention has unique heat resistance. In addition, hardened products, which usually have high heat resistance, have a high residual carbon content and tend to form a carbonized layer, making it difficult to achieve both tracking resistance and tracking resistance. Since it is low, it is suggested that it is difficult to form a carbonized layer and that the voltage resistance and tracking resistance are excellent. Therefore, it is expected to be applied in the field of electronic materials, especially in power devices requiring heat resistance, in-vehicle applications, and electronic materials used under high voltage.

The present invention will be specifically described below with reference to examples and comparative examples. However, the present invention is not limited to these. Unless otherwise specified, "parts" represent parts by weight and "%" represents weight percent. Moreover, the measurement method was each measured by the following methods.

1) Epoxy equivalent Using a potentiometric titrator, using methyl ethyl ketone as a solvent, adding a tetraethylammonium bromide acetic acid solution, and measuring using a 0.1 mol/L perchloric acid-acetic acid solution with a potentiometric titrator.

2) OH equivalent Using a potentiometric titrator, 1,4-dioxane is used as a solvent, acetylation is performed with 1.5 mol/L acetyl chloride, and excess acetyl chloride is decomposed with water to 0.5 mol/L-water. It was titrated using potassium oxide.

3) Melting point A DSC peak temperature was obtained with a differential scanning calorimeter (EXSTAR6000 DSC/6200, manufactured by SII Nanotechnology Co., Ltd.) under the condition of a heating rate of 5°C/min. That is, this DSC peak temperature was taken as the melting point of the resin.

4) Melt viscosity Measured at 150°C using a CAP2000H rotational viscometer manufactured by BROOKFIELD.

5) Softening point Measured by the ring and ball method according to JIS-K-2207.

6) GPC Measurement A main body (HLC-8220GPC, manufactured by Tosoh Corporation) equipped with columns (4 TSKgel SuperMultiporeHZ-N, manufactured by Tosoh Corporation) in series was used, and the column temperature was set to 40°C. Tetrahydrofuran (THF) was used as an eluent at a flow rate of 0.35 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 filtered through a microfilter, and 50 μL of the solution was used. For data processing, GPC-8020 model II version 6.00 manufactured by Tosoh Corporation was used.

7) Glass transition point (Tg)
Dynamic viscoelasticity was measured using a thermomechanical measurement device (EXSTA DMS6100 manufactured by SII Nanotechnology Co., Ltd.) under nitrogen flow, a temperature increase rate of 3 ° C./min, and 10 Hz, and the peak value of tan δ was taken as the glass transition temperature. and

8) 5% weight loss temperature (Td5), residual carbon ratio Using a thermogravimetric/differential thermal analyzer (EXSTAR DMA7300, manufactured by SII Nanotechnology), under the conditions of a temperature increase rate of 10 ° C./min under a nitrogen atmosphere , 5% weight loss temperature (Td5) was measured. Also, the weight loss at 700° C. was measured and calculated as the residual charcoal rate.

9) Thermal conductivity Thermal conductivity was measured by the unsteady hot wire method using a NETZSCH LFA447 thermal conductivity meter.

10) Melt-kneadability Melt-kneadability at 100°C was confirmed. ◯: kneadable, Δ: difficult to knead, ×: unmelted components present.

11) Solvent Solubility 2 g of the resin composition and 2 g of methyl ethyl ketone were weighed into a sample bottle and dissolved by heating, then the temperature was gradually lowered in a constant temperature bath, and the temperature in the bath where the resin was deposited was measured.
A precipitation temperature of 25°C or less was evaluated as ◯, a precipitation temperature of 26°C or more and less than 60°C was evaluated as Δ, and a precipitation temperature of 60°C or more was evaluated as x.

12) Field desorption ionization mass spectrometry (FD-MS)
It was measured using a mass spectrometer JMS-T100GCV (manufactured by JEOL Ltd.). A sample was dissolved in acetone and subjected to measurement.

Example 1
110.0 g of hydroquinone, 16.0 g of 36% hydrochloric acid, and 220.0 g of water were charged in a 2 L four-necked separable flask equipped with a thermometer, a stirrer, a condenser, and a Dean-Stark tube. C., 32.4 g of n-butyraldehyde and 19.8 g of paraldehyde were added dropwise, and the reaction was allowed to proceed for 6 hours while refluxing and dehydrating the system. After cooling to room temperature, filtration, neutralization and water washing were repeated, followed by drying under reduced pressure to obtain 102 g of a pale yellow solid phenolic compound (curing agent a). The OH equivalent of curing agent a is 70 g/eq. and the number average molecular weight was 1,200. The FD-MS spectrum of the obtained phenolic compound is shown in FIG. 1, and the GPC chart is shown in FIG. In FIG. 1, the cyclic compound _of n=4 of the general formula (3) (only R= _CH3 is 544, R= _CH3 / _CH2CH2CH3 =1/ ₃ is 573, R= _CH3 /CH _{. _ _ _ _ _ _ _ _} /CH ₂ CH ₂ CH ₃ =2/3 confirmed 736).

Example 2
The reaction was carried out in the same manner as in Example 1 except that 39.6 g of paraldehyde was used without using n-butyraldehyde to obtain 98 g of a phenolic compound. The OH equivalent of the obtained phenolic compound was 70 g/eq. and the number average molecular weight was 1,200.
Next, 25.0 g of the obtained phenolic compound, 500 g of epichlorohydrin, and 100 g of diethylene glycol dimethyl ether were placed in a 1 L four-necked separable flask, and 32.0 g of a 48% sodium hydroxide aqueous solution was added at 65° C. under reduced pressure (about 130 Torr). 4 g was added dropwise over 3 hours. During this time, the generated water was removed from the system by azeotroping with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After the dropwise addition was completed, the reaction was continued for 1 hour to remove water. After completion of the reaction, the reaction mixture was filtered and dried under reduced pressure to obtain 34.0 g of a pale yellow solid epoxy resin (epoxy resin A). The obtained epoxy resin A had a softening point of 101° C. and an epoxy equivalent of 155 g/eq. , and a number average molecular weight of 1,600. The FD-MS spectrum of the resulting epoxy resin is shown in FIG. 3, and the GPC chart is shown in FIG. The main peaks of m/z=992, 1240 and 1489 in FIG. 3 correspond to the cyclic compounds of R=CH ₃ and n=4, 5 and 6 of the general formula (2), respectively.

Example 3
The reaction was carried out in the same manner as in Example 1 except that the amount of n-butyraldehyde used was changed to 13.0 g and the amount of paraldehyde used was changed to 31.7 g to obtain 91 g of a phenolic compound. The OH equivalent of the obtained phenolic compound was 75 g/eq. and the number average molecular weight was 1,290. 25.0 g of the obtained phenolic compound was epoxidized in the same manner as in Example 2 to obtain 34.0 g of pale yellow solid epoxy resin (epoxy resin B). The obtained epoxy resin B had a softening point of 69° C. and an epoxy equivalent of 160 g/eq. , and a number average molecular weight of 1,660.

Comparative example 1
A flask equipped with a Dean-Stark tube was charged with 300.0 g of hydroquinone, 28.9 g of paraformaldehyde, and 263.1 g of diethylene glycol dimethyl ether. Next, 0.33 g of p-toluenesulfonic acid was added, the temperature was raised to 160° C., and the mixture was reacted for 6 hours while dehydrating to produce a phenolic compound. Diethylene glycol dimethyl ether was distilled off, methyl isobutyl ketone was added, neutralization, washing with water and filtration were carried out, and then methyl isobutyl ketone was distilled off under reduced pressure to obtain 295 g of a phenolic compound (curing agent b). The OH equivalent of curing agent b is 75 g/eq. , a number average molecular weight of 1500 and a softening point of 80°C.

Comparative example 2
The reaction was carried out in the same manner as in Example 1 except that n-butyraldehyde was not used, 39.6 g of paraldehyde was used, and 110.0 g of resorcinol was used in place of hydroquinone to obtain a white solid phenolic compound. 105 g were obtained (curing agent c). The OH equivalent of curing agent c was 73 g/eq. , and a melting point of 300° C. or higher.
When the obtained phenolic compound was epoxidized in the same manner as in Example 2, it exhibited self-polymerization, making it difficult to control the reaction and making synthesis impossible.

Examples 4-6 and Comparative Examples 3-7
As epoxy resin components, epoxy resin A obtained in Example 2, epoxy resin B obtained in Example 3, and epoxy resin C (o-cresol novolak type epoxy resin, YDCN-700-3, epoxy equivalent of 200 g/eq., Softening point 65 ° C., manufactured by Nippon Steel Chemical & Material), and epoxy resin D (4,4'-dihydroxydiphenyl ether type epoxy resin, epoxy equivalent 163 g / eq.; YSLV-80DE, manufactured by Nippon Steel Chemical & Material), As curing agents, the curing agent a obtained in Example 1, the curing agent b obtained in Comparative Example 1, the curing agent c obtained in Comparative Example 2, and the curing agent d (4,4′-dihydroxydiphenyl ether, OH equivalent 101 g / eq., manufactured by Tokyo Chemical Industry Co., Ltd.) and triphenylphosphine as a curing accelerator to obtain an epoxy resin composition having the formulation shown in Table 1. Numerical values in the table indicate parts by weight in the formulation. This epoxy resin composition was molded at 175° C. and post-cured at 175° C. for 5 hours to obtain a cured product test piece, which was subjected to various physical property measurements. Only in Comparative Example 7, the resin composition was heated and dissolved in 30 g of cyclohexanone, and cured in a vacuum press under reduced pressure at 130° C. for 15 minutes and at 250° C. for 80 minutes while applying a pressure of 2 MPa for evaluation of physical properties.

As is clear from these results, the epoxy resins obtained in the examples have excellent melt-kneadability and solvent solubility, and the cured products thereof have good thermal stability and thermal conductivity. Suitable.

Claims (7)

An epoxy resin represented by the following general formula (1).

(where A represents an aromatic group consisting of a benzene ring, biphenyl or naphthalene ring, G represents a glycidyl group, R each independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents 3 to 10 number.) The epoxy resin according to claim 1, represented by the following general formula (2).

(However, G is a glycidyl group, R each independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10.) A polyhydric hydroxy resin represented by the following general formula (3).

(However, each R independently represents a hydrocarbon group having 1 to 10 carbon atoms, and n represents a number of 3 to 10.) An epoxy resin composition comprising an epoxy resin and a curing agent, wherein the epoxy resin according to claim 1 is an essential component. An epoxy resin composition comprising an epoxy resin and a curing agent, characterized by containing the polyhydroxy resin according to claim 3 as an essential component as part or all of the curing agent. A cured epoxy resin obtained by curing the epoxy resin composition according to claim 4 or 5. A method for producing a polyhydric hydroxy resin represented by the general formula (3),
A method for producing a polyhydric hydroxy resin, which comprises reacting a hydroquinone represented by the following formula (4) with an aldehyde represented by the following formulas (5) and/or (6) in the presence of a strong acid. .

(However, R represents a hydrocarbon group having 1 to 10 carbon atoms.)

(However, R represents a hydrocarbon group having 1 to 10 carbon atoms.)

Images