JP2002179761A - Epoxy resin, epoxy resin composition and cured product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin with excellent solubility in solvents, giving a cured product having excellent heat resistance, moistureproofness, adhesiveness and low dielectric properties. SOLUTION: This epoxy resin is expressed by general formula (1) (where n is an average value in a range of 0.1 to 6.0) and characterized in that the softening point is 63 deg.C or higher, and the ratio (A/B) of the integrated value (A) of a peak existing in 35 to 37 ppm to the integrated value (B) of a peak existing in 40 to 42 ppm is 1.45 or more in the 13C-NMR spectrum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating material for electric and electronic parts such as a high-reliability semiconductor encapsulation, and various kinds of materials such as a laminate (printed wiring board) and CFRP (carbon fiber reinforced plastic). The present invention relates to an epoxy resin useful for composite materials, adhesives, paints, etc., an epoxy resin composition containing the same, and a cured product thereof.

[0002]

2. Description of the Related Art Epoxy resins are used in the fields of electric and electronic parts, structural materials, adhesives, paints, etc. due to workability and excellent electrical properties, heat resistance, adhesiveness, moisture resistance (water resistance), etc. of the cured product. Widely used in

In recent years, particularly in the electric and electronic fields, further improvements in various properties such as heat resistance, moisture resistance, adhesion, and low dielectric constant have been demanded. As structural materials, lightweight and excellent in mechanical properties are required for aerospace materials, leisure and sports equipment applications, and the like. Many proposals have been made for epoxy resins in response to these requirements.However, in applications where the varnish is used, the epoxy resin has poor solubility in solvents. In some cases, problems such as observation of crystalline precipitates occur.

[0004]

SUMMARY OF THE INVENTION The present invention relates to an insulating material for electric / electronic parts (such as a highly reliable semiconductor encapsulant) which exhibits excellent heat resistance, moisture resistance (water resistance) and low dielectric properties in the cured product. ) And laminated boards (such as printed wiring boards) and CFRP
It is an object of the present invention to provide an epoxy resin which is useful for various composite materials, including adhesives, paints, etc. and which has excellent solvent solubility, an epoxy resin composition containing them, and a cured product thereof.

[0005]

Means for Solving the Problems The present inventors have made intensive studies on epoxy resins having the above-mentioned characteristics, and have completed the present invention. That is, the present invention provides (1) general formula (1)

[0006]

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(Where n is an average value, and 0.1 to 6.
Indicates a positive number of 0. In the 13C-NMR spectrum, the ratio (A / B) of the integrated value (A) of the peak existing at 35 to 37 ppm and the integrated value (B) of the peak existing at 40 to 42 ppm is 1.45. Above, and the epoxy resin characterized by its softening point is 63 ℃ or more,
(2) an epoxy resin composition comprising the epoxy resin and the curing agent according to the above (1), (3) an epoxy resin composition according to the above (2) containing a curing accelerator, and (4) the above (2) And (3) a varnish obtained by dissolving the epoxy resin composition according to (2) or (3) in a solvent.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The epoxy resin of the present invention has the formula (2)

[0009]

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(Where n is an average value, and 0.1 to 6.
Indicates a positive number of 0. )) And a glycidylation reaction in which the phenol aralkyl resin is reacted with epihalohydrin. The phenol aralkyl resin of the formula (2) used is, for example, a compound represented by the formula (3) as disclosed in JP-A-8-143648.

[0011]

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It is obtained by reacting a biphenyl derivative represented by (X represents an alkoxy group) with phenol. When a solvent is used in the reaction, the proportion of the biphenyl derivative and phenol used in obtaining the phenol aralkyl resin may be different depending on the type thereof. When it is determined and it is not possible to say unconditionally, when the reaction is carried out without a solvent, the amount of phenol is generally 1.1 to 2.9 mol, preferably 1.5 to 2.8 mol, per 1 mol of the biphenyl derivative.

The epihalohydrin used in the glycidylation reaction for obtaining the epoxy resin of the present invention includes epichlorohydrin, epibromhydrin, epiiodohydrin and the like, but epichlorohydrin which is industrially available and inexpensive is preferable. . This reaction can be performed according to a conventionally known method.

For example, a solid of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is added to a mixture of the phenol aralkyl resin and epihalohydrin,
Alternatively, the reaction is carried out at 20 to 120 ° C. for 0.5 to 10 hours while adding. At this time, the alkali metal hydroxide may be used in the form of an aqueous solution.In this case, the alkali metal hydroxide is continuously added, and water and epichlorohydrin are continuously removed from the reaction mixture under reduced pressure or normal pressure. A method may be employed in which the water is removed by distilling and separating water, and epichlorohydrin is continuously returned during the reaction and mixing.

In the above method, the amount of epihalohydrin used is usually 0.5 to 20 mol, preferably 0.7 to 10 mol, per equivalent of the hydroxyl group of the phenol aralkyl resin. The amount of the alkali metal hydroxide to be used is usually 0.5 to 1 to 1 equivalent of the hydroxyl group of the phenol aralkyl resin.
It is 5 mol, preferably 0.7 to 1.2 mol. Also,
By adding an aprotic solvent such as dimethyl sulfone, dimethyl sulfoxide, dimethylformamide, and 1,3-dimethyl-2-imidazolidinone, an epoxy resin having a low hydrolyzable halogen content defined below is obtained,
This epoxy resin is particularly suitable for electronic material sealing applications.

The amount of the aprotic polar solvent used is from 5 to 200%, preferably from 10 to 200% by weight of the epihalohydrin.
100%. The addition of alcohols with methanol and ethanol other than the above solvents facilitates the reaction. Further, toluene, xylene and the like can also be used. Here, the amount of hydrolyzable halogen can be measured, for example, by placing the epoxy resin in dioxane and titrating with a KOH / ethanol solution while refluxing for several tens minutes.

A quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide or trimethylbenzylammonium chloride is used as a catalyst in a mixture of a phenol aralkyl resin and an excess of epihalohydrin at 50-150 ° C.
The reaction is performed for 10 to 10 hours, and a solid or aqueous solution of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is added to the resulting halohydrin ether of the phenol aralkyl resin, and the reaction is performed again at 20 to 120 ° C. for 1 to 10 hours. The epoxy resin of the present invention can be obtained by ring closure of halohydrin ether. The amount of the quaternary ammonium salt used in this case is usually 0.001 to 0.2 mol, preferably 0.05 to 0.2 mol per equivalent of the hydroxyl group of the phenol mixture.
0.1 mol. The amount of the alkali metal hydroxide to be used is generally 0.8 to 1.5 mol, preferably 0.9 to 1.1 mol, per equivalent of the hydroxyl group of the phenol aralkyl resin.

Usually, these reaction products are washed with water, or without heating, under heating and reduced pressure to remove excess epihalohydrins, solvents and the like, and then dissolved again in a solvent such as toluene and methyl isobutyl ketone. By adding an aqueous solution of an alkali metal hydroxide such as potassium hydroxide and reacting again, the epoxy resin of the present invention having a low hydrolyzable halogen concentration can be obtained. In this case, the amount of the alkali metal hydroxide used is usually 0.01 to 0.2 mol, preferably 0.05 to 0.1 mol, per 1 equivalent of the hydroxyl group of the phenol aralkyl resin. The reaction temperature is usually 50 to 120 ° C, and the reaction time is usually 0.5 to 2 hours.

After completion of the reaction, the by-produced salts are removed by filtration, washing with water, etc., and the solvent of the present invention having a low hydrolyzable halogen concentration is obtained by distilling off solvents such as toluene and methyl isobutyl ketone under heating and reduced pressure. A resin can be obtained.

In the ¹³ C-NMR spectrum of the epoxy resin of the present invention, the peak existing at 35 to 37 ppm means that the position at which the methylene group on the aromatic ring is bonded is ortho to the 2,3-epoxypropoxy group. It means there is. The peak present at 40 to 42 ppm means that the position at which the methylene group on the aromatic ring is bonded is para to the 2,3-epoxypropoxy group.

The epoxy resin of the present invention has its ¹³ C-NM
In the R spectrum, the ratio (A / B) of the integrated value (A) of the peak existing at 35 to 37 ppm to the integrated value (B) of the peak existing at 40 to 42 ppm is 1.45 or more, and the softening point is 63. C. or higher is preferred from the viewpoint of solvent solubility.

Hereinafter, the epoxy resin composition of the present invention will be described. The epoxy resin composition of the present invention can be used alone or in combination with another epoxy resin. When used together, the proportion of the epoxy resin of the present invention in the total epoxy resin is preferably at least 30% by weight, particularly preferably at least 40% by weight.

Other epoxy resins which can be used in combination with the epoxy resin of the present invention include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, terpene diphenol, 4,4'-biphenol,
2,2'-biphenol, 3,3 ', 5,5'-tetramethyl- [1,1'-biphenyl] -4,4'-diol, hydroquinone, resorcinol, naphthalenediol, tris- (4-hydroxyphenyl ) Methane, 1,
1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenols (phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.) and formaldehyde, acetaldehyde, benzaldehyde, p-
Hydroxybenzaldehyde, o-hydroxybenzaldehyde, p-hydroxyacetophenone, o-hydroxyacetophenone, dicyclopentadiene, furfural, 4,4′-bis (chloromethyl) -1,1′-biphenyl, 4,4′-bis (methoxy Methyl) -1,
Polycondensates with 1'-biphenyl, 1,4'-bis (chloromethyl) benzene, 1,4'-bis (methoxymethyl) benzene and the like, modified products thereof, and halogenated bisphenols such as tetrabromobisphenol A And solid or liquid epoxy resins such as glycidyl ether compounds derived from alcohols, alicyclic epoxy resins, glycidylamine epoxy resins, and glycidyl ester epoxy resins, but are not limited thereto. These may be used alone or in combination of two or more.

The epoxy resin composition of the present invention contains a curing agent in a preferred embodiment. Examples of the curing agent include amine compounds, acid anhydride compounds, amide compounds, and phenol compounds. Specific examples of the curing agent that can be used include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, dicyandiamide, a polyamide resin synthesized from a dimer of linolenic acid and ethylenediamine, phthalic anhydride, and trimellit anhydride. Acid, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol , Terpene diphenol, 4,4'-biphenol, 2,2'-biphenol, 3,3 ', 5,5'-tetramethyl- [1,1'-
Biphenyl] -4,4'-diol, hydroquinone,
Resorcinol, naphthalene diol, tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenols (phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, Dihydroxynaphthalene) and formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, o-hydroxybenzaldehyde, p-hydroxyacetophenone, o-hydroxyacetophenone, dicyclopentadiene, furfural, 4,4′-bis (chloromethyl) -1, 1'-biphenyl, 4,4'-
Bis (methoxymethyl) -1,1′-biphenyl, 1,
4'-bis (chloromethyl) benzene, 1,4'-bis (methoxymethyl) polycondensate of benzene and modified products thereof, halogenated bisphenols such as tetrabromobisphenol A, imidazole, BF 3 _- amine Examples include, but are not limited to, complexes and guanidine derivatives. These may be used alone,
Two or more types may be used.

The amount of the curing agent used in the epoxy resin composition of the present invention is preferably 0.5 to 1.5 equivalents, more preferably 0.6 to 1.2 equivalents, per equivalent of the epoxy group of the epoxy resin. . When less than 0.5 equivalent, or more than 1.5 equivalent to 1 equivalent of epoxy group,
In any case, curing may be incomplete and good cured physical properties may not be obtained.

When the above curing agent is used, a curing accelerator may be used in combination. Examples of the curing accelerator that can be used include 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, and 2-ethyl-4.
Imidazoles such as -methylimidazole, tertiary amines such as 2- (dimethylaminomethyl) phenol, triethylenediamine, triethanolamine, 1,8-diazabicyclo (5,4,0) undecene-7, triphenylphosphine Organic phosphines such as diphenylphosphine and tributylphosphine, metal compounds such as tin octylate, tetra-substituted phosphonium / tetra-substituted borates such as tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenylborate, and 2-ethyl-. Tetraphenylboron salts such as 4-methylimidazole / tetraphenylborate and N-methylmorpholine / tetraphenylborate. When the curing accelerator is used, the amount is 0.01 to 15 parts by weight per 100 parts by weight of the epoxy resin.
Parts by weight are used as needed.

Further, the epoxy resin composition of the present invention comprises
If necessary, various additives such as an inorganic filler, a silane coupling agent, a release agent, and a pigment, and various thermosetting resins can be added. As inorganic fillers, crystalline silica, fused silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, fosterite, steatite, spinel,
Examples include powders of titania, talc, and the like, or beads obtained by spheroidizing them, but are not limited thereto. These may be used alone or in combination of two or more. These fillers are preferably used in a proportion occupying 50 to 90% by weight in the epoxy resin composition from the viewpoint of heat resistance, moisture resistance, mechanical properties and the like of the cured product of the epoxy resin composition.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the above components. And the epoxy resin composition of this invention can be easily made into the hardened | cured material by the method similar to the conventionally well-known method. For example, the epoxy resin of the present invention and a curing agent, and if necessary, a curing accelerator and an inorganic filler, a compounding agent, and various thermosetting resins, if necessary, using an extruder, a kneader, a roll, or the like, until they become uniform. The epoxy resin composition of the present invention is obtained by thorough mixing, and the epoxy resin composition is molded by a melt casting method, a transfer molding method, an injection molding method, a compression molding method, and the like.
The cured product of the present invention can be obtained by heating at 0 ° C. for 2 to 10 hours.

Further, since the epoxy resin of the present invention has excellent solvent solubility and does not form crystals, the epoxy resin composition of the present invention is dissolved in a solvent to form a varnish, so that the epoxy resin can be used as an adhesive for laminated boards and the like. It can be suitably used. In this case, for example, the epoxy resin composition of the present invention is toluene, xylene,
Dissolve in a solvent such as acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, ethylene glycol monomethyl ether, N-methyl-2-pyrrolidone, etc., and remove glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper, etc. A prepreg obtained by impregnating a substrate and drying by heating is subjected to hot press molding to obtain a cured product, or γ-butyrolactones, N-methylpyrrolidone (NMP), N, N-dimethylformamide (DMF), N, N -Dimethylacetamide, N, N-
Amide solvents such as dimethylimidazolidinone, sulfones such as tetramethylene sulfone, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, ether solvents such as propylene glycol monobutyl ether, It can be dissolved in a ketone solvent such as methyl ethyl ketone and methyl isobutyl ketone and an aromatic solvent such as toluene and xylene to obtain a sheet described below. In this case, in the case of prepreg applications, the solvent is usually 10 to 70% by weight, preferably 15 to 70% by weight in a mixture of the epoxy resin composition of the present invention and the solvent.
An amount occupying 70% by weight is used. In the case of sheet use, a solvent is used in such an amount that the solid content concentration in the obtained varnish is usually 10 to 80% by weight, preferably 20 to 70% by weight.

When the varnish is used in the form of a sheet, the varnish is dried on a substrate by various coating methods known per se, such as gravure coating, screen printing, metal masking, and spin coating. Is used after being coated so as to have a predetermined thickness, for example, 5 to 100 μm. Which coating method is used is appropriately selected depending on the type, shape, size, and film thickness of the base material. . As a substrate,
For example, films made of various polymers such as polyamide, polyamide imide, polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyetheretherketone, polyetherimide, polyetherketone, polyketone, polyethylene, polypropylene and / or copolymers thereof. Or a metal foil such as a copper foil, and particularly preferably a polyimide film or a copper foil. When a release film is used, it is used as a bonding sheet. A bonding sheet is a product in which an adhesive layer (varnish) is applied to one side of a release film and another release agent is attached to it. An adhesive material for bonding a flexible printed wiring board to a flexible printed wiring board Used as By heating the sheet thus obtained, a sheet-like cured product can be obtained.

[0031]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
In the Synthesis Examples, Examples and Comparative Examples, parts mean parts by weight. The epoxy equivalent, softening point, and melt viscosity were measured under the following conditions.・ Epoxy equivalent Measured by the method according to JIS K-7236, and the unit is g.
/ Eq. -Softening point It was measured by a method according to JIS K-7234.・ Melting viscosity Melting viscosity at 150 ° C in the cone plate method Instrument: cone plate (ICI) high temperature viscometer (RESE)
ACH EQUIPMENT (LONDON) LTD. : 3 (measurement range: 0 to 2.00 Pa · s) Sample amount: 0.15 ± 0.01 g

Synthesis Example 1 In a four-necked flask equipped with a stirrer, a thermometer, and a condenser, 382 parts of phenol, 485 parts of 4,4'-bis (methoxymethyl) -1,1'-biphenyl, and paratoluenesulfonic acid monohydrate 8 parts of the Japanese product was charged and reacted for 4 hours while maintaining the reaction temperature at 125 ° C. During that time, formed methanol was distilled out of the reaction system. After completion of the reaction, 1500 parts of methyl isobutyl ketone (MIBK) was added, and washing with water was repeated. Then, unreacted phenol and MIBK were distilled off from the oil layer under heating and reduced pressure to obtain 615 parts of a phenol aralkyl resin (P1). The obtained phenol aralkyl resin (P1) has a softening point of 92 ° C. and a melt viscosity of 0.2.
The hydroxyl group equivalent was 91 Pa · s and the hydroxyl equivalent was 223 g / eq.

Synthesis Example 2 The same operation as in Synthesis Example 1 was carried out except that 382 parts of phenol was changed to 430 parts, and 726 parts of phenol aralkyl resin (P2) was obtained. The obtained phenol aralkyl resin (P2) had a softening point of 85 ° C., a melt viscosity of 0.47 Pa · s, and a hydroxyl equivalent of 220 g / eq.

Synthesis Example 3 The same operation as in Synthesis Example 1 was performed except that 382 parts of phenol was changed to 478 parts, and 620 parts of phenol aralkyl resin (P3) was obtained. The obtained phenol aralkyl resin (P3) had a softening point of 82 ° C., a melt viscosity of 0.35 Pa · s, and a hydroxyl equivalent of 215 g / eq.

Synthesis Example 4 The same operation as in Synthesis Example 1 was carried out except that 382 parts of phenol were changed to 506 parts, and 632 parts of phenol aralkyl resin (P4) was obtained. The obtained phenol aralkyl resin (P4) had a softening point of 79 ° C., a melt viscosity of 0.25 Pa · s, and a hydroxyl equivalent of 212 g / eq.

Synthesis Example 5 611 parts of a phenol aralkyl resin (P5) was obtained in the same manner as in Synthesis Example 1 except that 382 parts of phenol was changed to 573 parts. The obtained phenol aralkyl resin (P5) had a softening point of 74 ° C., a melt viscosity of 0.15 Pa · s, and a hydroxyl equivalent of 211 g / eq.

Synthesis Example 6 The same operation as in Synthesis Example 1 was carried out except that 382 parts of phenol was changed to 611 parts, and 615 parts of phenol aralkyl resin (P6) was obtained. The obtained phenol aralkyl resin (P6) had a softening point of 71 ° C., a melt viscosity of 0.12 Pa · s, and a hydroxyl equivalent of 207 g / eq.

Synthesis Example 7 A four-necked flask equipped with a stirrer, a thermometer and a condenser was charged with 955 parts of phenol and stirred at 50 ° C. while stirring at 4,4′-bis (chloromethyl) -1,1′-biphenyl 1256. And 10 parts of paratoluenesulfonic acid monohydrate, and added at 50 ° C. for 1.5 hours, 70 ° C. for 1 hour, 80 ° C.
For 2 hours. After the reaction is completed, MIBK 2500
Was added and the washing was repeated. Then, unreacted phenol and MIBK were distilled off from the oil layer under heating and reduced pressure to obtain 1457 parts of a phenol aralkyl resin (P7). The obtained phenol aralkyl resin (P7) had a softening point of 82 ° C., a melt viscosity of 0.40 Pa · s, and a hydroxyl equivalent of 221 g / eq.

Synthesis Example 8 The same operation as in Synthesis Example 7 was carried out except that 955 parts of phenol was changed to 1481 parts, to obtain 1729 parts of a phenol aralkyl resin (P8). The obtained phenol aralkyl resin (P8) has a softening point of 71 ° C., a melt viscosity of 0.12 Pa · s, and a hydroxyl equivalent of 207 g / eq.
Met.

Example 1 To 446 parts of the resin (P1) obtained in Synthesis Example 1, 925 parts of epichlorohydrin and 185 parts of dimethylsulfoxide were added and dissolved. The mixture was heated to 45 ° C. and flaked sodium hydroxide (purity: 99%). 82 parts were added over 90 minutes, and then the mixture was further reacted at 45 ° C. for 2 hours and at 70 ° C. for 0.5 hour. Then, after washing was repeatedly returned to neutrality, excess epichlorohydrin was distilled off from the oil layer under heating and reduced pressure, and 115 parts of MIBK was added to the residue to dissolve it. Further, the MIBK solution was heated to 70 ° C., 27 parts of a 30% by weight aqueous sodium hydroxide solution was added, and the mixture was allowed to react for 1 hour. Then, heating under reduced pressure from the oil layer,
By removing MIBK, 475 parts of the epoxy resin (E1) of the present invention was obtained. The obtained epoxy resin (E
FIG. 1 shows the ¹³ C-NMR spectrum (CDCL ₃ , 300 MHz) of 1).
Shown in

Example 2 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was carried out except that 46 parts were changed to 439 parts of the resin (P2) obtained in Synthesis Example 2, to obtain 474 parts of the epoxy resin (E2) of the present invention.

Example 3 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was performed, except that 46 parts were changed to 430 parts of the resin (P3) obtained in Synthesis Example 3, to obtain 502 parts of an epoxy resin (E3) of the present invention.

Example 4 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was performed except that 424 parts of the resin (P4) obtained in Synthesis Example 4 was used instead of 46 parts to obtain 493 parts of the epoxy resin (E4) of the present invention.

Comparative Example 1 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was carried out except that 425 parts of the resin (P5) obtained in Synthesis Example 5 was used instead of 46 parts to obtain 492 parts of an epoxy resin (E5) for comparison.

Comparative Example 2 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was performed except that 46 parts were replaced with 414 parts of the resin (P6) obtained in Synthesis Example 6, to obtain 500 parts of a comparative epoxy resin (E6).

Comparative Example 3 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was performed except that 46 parts were changed to 442 parts of the resin (P7) obtained in Synthesis Example 7, to obtain 504 parts of an epoxy resin (E7) for comparison.

Comparative Example 4 In Example 1, the resin (P1) 4 obtained in Synthesis Example 1 was used.
The same operation as in Example 1 was performed except that 46 parts were changed to 414 parts of the resin (P8) obtained in Synthesis Example 8, to obtain 500 parts of a comparative epoxy resin (E8).

Tables 1 and 2 show the physical properties of the epoxy resin of the present invention and the comparative epoxy resin obtained in the above Examples and Comparative Examples.

Table 1 Example 1 Example 2 Example 3 Example 4 Epoxy equivalent (g / eq) 289 291 286 278 Softening point (° C) 79 73 68 65 Melt viscosity (Pa · s) 0.79 0.45 0.27 0.22 A / B 1.83 1.76 1.63 1.50

Table 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Epoxy equivalent (g / eq) 278 278 295 278 Softening point (° C.) 61 58 71 58 Melt viscosity (Pa · s) 0.14 0.10 0.37 0.11 A / B 1.54 1.33 1.21 0.95

Test Examples 1 to 8 Epoxy resins (E1) to (E1) obtained in Examples 1 to 4
4), epoxy resins (E5) obtained in Comparative Examples 1 to 4
(E8) was dissolved in methyl ethyl ketone as a solvent so that the resin concentration became 70% by weight, and stored in a 5 ° C. environment. The test results are shown in Table 3 (from left to right for the resins obtained in Examples 1 to 4) and Table 4 (from left to right for the resins obtained in Comparative Examples 1 to 4). The criteria are shown below. ：: No crystal precipitation even after one week or more after dissolution ×: Crystal precipitation within one week after dissolution

Table 3 Test Example 1 Test Example 2 Test Example 3 Test Example 4 Epoxy resin E1 E2 E3 E4 Test results ○ ○ ○ ○

Table 4 Test Example 6 Test Example 7 Test Example 8 Test Example 9 Epoxy resin E5 E6 E7 E8 Test results × × × ×

A / B and softening points of the epoxy resins (E1) to (E4) obtained in Examples 1 to 4 and the epoxy resins (E5) to (E6) obtained in Comparative Examples 1 to 4 FIG. 2 shows a graph. Test Examples and Comparative Test Examples The epoxy resin of the present invention having an A / B and softening point within a specific range exhibits better solvent solubility than epoxy resins outside the range.

Example 6 The epoxy resin (E2) obtained in Example 2 and a phenol novolak resin as a curing agent (PN-80: manufactured by Nippon Kayaku Co., Ltd., hydroxyl equivalent 105 g / eq, softening point 86)
C), 2-ethyl-4-methylimidazole (2E4MZ) as a hardening accelerator, methyl ethyl ketone (MEK) and methyl cellosolve (MCS) as diluents in a weight ratio shown in the column of (Blending) in Table 5 to form a varnish. Was prepared. Using this varnish, a glass cloth (WEA18W1)
05F115N: Nitto Boseki Co., Ltd.)
A semi-cured prepreg was obtained by drying with a hot air drier at 120 ° C. for 7 minutes. Eight prepregs and copper foil (JTC foil, 35 μm, manufactured by Nikko Gould Co., Ltd.) are stacked on top of each other and 40 kgf
/ Cm ² at 170 ° C for 60 minutes.
A glass cloth laminate was made. The characteristics of the prepared laminate were measured by the following items and methods. Table 5 shows the measurement results. -Glass transition temperature Thermomechanical instrument (TMA): Vacuum Science and Technology TM-7000 Heating rate: 2 ° C / min.・ Copper foil peel strength Tensile tester: Toyo Baldwin Tensilon RTM
-500 Tensile mode: 180 ° peeling Crosshead speed: 200 mm / min. Measurement temperature: 30 ° C. Water absorption Test piece: 5 cm × 5 cm Weight increase after boiled in hot water at 100 ° C. for 24 hours (% by weight) Dielectric constant Measured in accordance with JIS 6481

Comparative Example 6 A brominated bisphenol A type epoxy resin (Epomic R-232: manufactured by Mitsui Chemicals, Inc., epoxy equivalent: 483 g / eq) as an epoxy resin, and a phenol novolak resin (PN-80: Nippon Kayaku) as a curing agent Co., Ltd., hydroxyl equivalent 105 g / eq, softening point 86 ° C.), 2-ethyl-4-methylimidazole (2E4M) as a curing accelerator
Z) and methyl ethyl ketone (MEK) and methyl cellosolve (MCS) as diluents were blended in the weight ratios shown in the column of (blending) in Table 5 to prepare a varnish. The subsequent operation was performed in the same manner as in Example 6. Table 5 shows the measurement results.

Table 5 Example 6 Comparative Example 6 (Blending) E2 100 R-232 100 PN-80 36 322 2E4MZ 0.3 0.3 MEK 82 73 MCS 98 (cured physical properties) Glass transition temperature (° C.) 140 125 Copper foil peel strength (kN / m) 2.8 1.9 Water absorption (%) 0.6 0.5 Dielectric constant 4.6 4.8

From Table 5, it is clear that the cured product of the present invention is different from the bisphenol A type epoxy resin generally used conventionally.
Excellent heat resistance, adhesion and water resistance, and low dielectric properties.

[0059]

The epoxy resin composition containing the epoxy resin of the present invention has excellent heat resistance, adhesion, moisture resistance and low dielectric properties in the cured product. Therefore, it is extremely useful when used as an insulating material for electric / electronic parts, a laminated board (such as a printed wiring board), various composite materials including CFRP, an adhesive, and a paint.

[Brief description of the drawings]

FIG. 1 shows the epoxy resin ^{13 of} the present invention obtained in Example 1.
C-NMR spectrum. In FIG. 1, the vertical axis represents the intensity of absorption, and the horizontal axis represents ppm.

FIG. 2 shows 35 to 37 ppm in ¹³ C-NMR spectra of the epoxy resin of the present invention and a comparative epoxy resin.
The graph which graphed the relationship between the softening point and the ratio (A / B) of the integrated value (A) of the peak which exists in, and the integrated value (B) of the peak which exists in 40-42 ppm.は indicates the epoxy resin (E1) to (E4) of the present invention, and X indicates the epoxy resin (E) for comparison.
5) to (E8). The epoxy resin of the present invention is present in the shaded area.

Claims (5)

[Claims] 1. A compound of the general formula (1) (In the formula, n is an average value and represents a positive number of 0.1 to 6.0.) In the ¹³ C-NMR spectrum, an integrated value (A) of a peak existing at 35 to 37 ppm
And the ratio (A / B) of the integrated value (B) of the peak existing at 40 to 42 ppm and its softening point is 63 ° C.
An epoxy resin characterized by the above. 2. An epoxy resin composition comprising the epoxy resin according to claim 1 and a curing agent. 3. The epoxy resin composition according to claim 2, further comprising a curing accelerator. 4. A cured product obtained by curing the epoxy resin composition according to claim 2 or 3. 5. A varnish obtained by dissolving the epoxy resin composition according to claim 2 in a solvent.