JP5486505B2 - Phenol resin mixture, epoxy resin mixture, epoxy resin composition, and cured product - Google Patents

Description

  The present invention relates to a novel phenol resin mixture, an epoxy resin mixture, an epoxy resin composition, and a cured product.

Epoxy resin composition has excellent workability and excellent electrical properties, heat resistance, chemical resistance, mechanical strength, adhesion, moisture resistance (water resistance), dimensional stability, optical characteristics, etc. Utilized in a wide range of fields such as electrical / electronic component materials, reinforced fiber composite materials, resist materials, optical materials, liquid crystal sealing materials, overcoat materials, prepregs, molding materials, adhesives, adhesives, paints, etc. Yes.
For example, as electrical / electronic component materials, (1) semiconductor sealing materials, specifically (a) potting, dipping, transfer mold sealing, flip-flops for capacitors, transistors, diodes, light emitting diodes, ICs, LSIs, etc. Underfill for chips, etc. (b) Underfill for sealing and reinforcement when mounting IC packages such as QFP, BGA, CSP, etc. (2) Substrate materials such as printed wiring boards and build-up laminates, and Multilayer substrate interlayer adhesives, die bonding agents, semiconductor adhesives such as underfill, (3) BGA reinforcing underfill, anisotropic conductive films, mounting adhesives such as anisotropic conductive paste, etc. Can be mentioned. Reinforcing fiber composite materials are typified by CFRP used in car bodies, ships, aircraft structural materials, materials for leisure and sports equipment such as tennis rackets and golf club shafts, and fuel cell separators. Structural materials are mentioned. Examples of the resist material include a solder resist, a color resist, and a black matrix. Examples of the optical material include lens materials.
In recent years, in the use of electrical / electronic component materials, as electrical / electronic equipment has become more sophisticated, electrical / electronic components have become increasingly dense and highly integrated, Due to the expansion of fields of application to high-temperature environments, outdoor environments, the vicinity of the human body, etc., and the shift to environmentally friendly technologies, the required characteristics have become widespread and sophisticated.
For example, in the fields of semiconductor sealing materials and substrates, epoxy resins are required to have flame resistance and solder crack resistance in addition to heat resistance, water absorption, electrical insulation, low thermal expansion coefficient, and the like.

  Regarding the flame retardancy of epoxy resins, flame retarding techniques using flame retardants such as halogen-based epoxy resins and phosphorus atom-containing epoxy resins themselves and flame retardants such as antimony trioxide have been studied. However, when these halogens or antimony are used, it has been pointed out that if the used article is not properly disposed of, it contributes to the generation of toxic substances such as dioxins. For these reasons, there is a growing demand for flame retardant technologies such as “halogen-free, antimony-free, and phosphorus-free”. In response to this requirement, a resin skeleton that exhibits flame retardancy without using halogen or a flame retardant has been proposed. For example, a phenol-biphenyl aralkyl type epoxy resin is known as a resin that exhibits flame retardancy without using a halogen or a flame retardant (Patent Documents 1 and 2).

  Further, changes in the mounting process have an influence on the solder crack resistance. In other words, in the semiconductor mounting method, the surface mounting method has become common, and the semiconductor package is often directly exposed to high temperatures during solder reflow, and when the semiconductor is mounted as the awareness of environmental problems in recent years has increased. Increasing use of lead-free solder. Since lead-free solder has a melting temperature about 20 ° C. higher than that of conventional solder (about 260 ° C.), the possibility of package cracks during solder reflow is much higher than before. In addition, there is an increasing demand for higher density, higher integration, and miniaturization in printed wiring boards on which electronic components such as LSI are mounted. For this reason, the wiring width is reduced and the through-hole diameter is reduced. Therefore, it is necessary to reduce the plating thickness. However, when the plating thickness is reduced, cracks may occur during thermal shock, and the wiring board is required to have high solder crack resistance. For these reasons, the epoxy resin composition used for electrical and electronic materials around semiconductors such as semiconductor encapsulating materials and printed wiring boards is hardened by lead-free solder, which has a higher temperature than conventional solder. There is a demand for performance that does not easily cause cracks. This crack is caused by the stress generated in the cured product when subjected to the thermal shock of lead-free solder. As one of the evaluation indexes, a storage elastic modulus by a dynamic viscoelasticity test can be used. In general, it is known that the storage elastic modulus at a high temperature is preferably lower if the storage elastic modulus at 160 ° C. is 100 MPa or more (Patent Document 3). On the other hand, it is known that the storage elastic modulus at high temperature should be higher to some extent even at the glass transition temperature or higher. During solder reflow at 220 ° C. to 260 ° C. and heat cycle at −50 to 150 ° C. An epoxy resin composition having a storage elastic modulus at 220 ° C. of 0.5 GPa to 0.9 GPa is disclosed as a highly reliable resin in which cracks do not occur (Patent Document 4). Therefore, an appropriate storage elastic modulus at a high temperature is considered to be very important in order to suppress the occurrence of cracks due to thermal shock.

As a phenol-biphenyl aralkyl type epoxy resin having excellent flame retardancy, for example, NC-3000 series manufactured by Nippon Kayaku Co., Ltd. is known as a commercial product. This epoxy resin can be produced by reacting 4,4′-dimethylolbiphenyl with phenol, isolating the resulting bisphenol compound, and then epoxidizing the isolated bisphenol compound with epichlorohydrin or the like. (For example, Patent Document 5). A method using 4,4′-bis (chloromethyl) -biphenyl instead of the above 4,4′-dimethylolbiphenyl is also known (Patent Document 6).
In recent developments related to phenol-biphenyl aralkyl type epoxy resins, for example, phenol resins in which biphenyl derivatives such as 4,4′-bis (chloromethyl) -biphenyl are previously oligomerized and condensed with phenols have been proposed. (Patent Document 7).
In addition, a method for synthesizing 4,4′-bis (chloromethyl) -biphenyl, which is the above raw material, by bischloromethylation of biphenyl is generally known. For example, biphenyl, paraformaldehyde and chlorinated in a cyclohexane solvent. 4,4′-bis (chloromethyl) -biphenyl can be obtained by introducing hydrogen chloride gas and reacting with vigorous stirring of zinc (Patent Document 8, page 10, columns 19-20).

JP-A-11-140277 JP-A-11-140166 Patent No. 4027332 JP 2001-288244 A Japanese Patent No. 2952094 JP 2002-338656 A Japanese Patent Laid-Open No. 2007-254685 Japanese Patent Publication No.54-929

  An object of the present invention is to provide an epoxy resin cured product having flame retardancy equivalent to or higher than that of a cured product using a phenol-biphenylaralkyl type epoxy resin excellent in flame retardancy, and having a more optimal storage elastic modulus, To provide an epoxy resin mixture, or / and an epoxy resin composition, and a phenol resin mixture for the epoxy resin.

  As a result of diligent research to solve the above problems, the present inventors surprisingly include bishalomethylbiphenyl as a main component, a certain amount of tri- and tetrahalomethylbiphenyl as side reaction products, and the balance. A phenol resin mixture obtained by reacting a reaction product (mixture) obtained by halomethylation of biphenyl containing a small amount of monohalomethylbiphenyl and bisbiphenylylmethane compound with phenol without isolation and purification is The present invention was completed by finding that it is very suitable as a raw material for an epoxy resin mixture satisfying the above required performance.

That is, the present invention
(1) Tri (halomethyl) biphenyl obtained by halomethylation reaction of biphenyl and in a ratio (GC area ratio) to the total reaction product in GC-MS, with bishalomethylbiphenyl being 60% or more and less than 80%. And a reaction product containing a total of 15 to 30% of tetra (halomethyl) biphenyl and the other by-products, and a phenol resin mixture obtained by a methylene crosslinking reaction with phenol,
(2) The above (1), wherein the softening point is 65 to 85 ° C., the number average molecular weight by GPC (gel permeation chromatography) is 350 to 1200, the weight average molecular weight is 400 to 2000, and the OH equivalent is 160 to 250 g / eq. A phenolic resin mixture according to
(3) An epoxy resin mixture obtained by epoxidizing the phenol resin mixture according to (1) or (2) above,
(4) Softening point of 50 to 75 ° C., ICI viscosity of 0.02 to 0.50 Pa · s, number average molecular weight by GPC (gel permeation chromatography) of 400 to 1200, weight average molecular weight of 800 to 2000, epoxy The epoxy resin mixture according to the above (3), wherein the equivalent is 200 to 360 g / eq,
(5) An epoxy resin composition containing the epoxy resin mixture and a curing agent according to (3) above,
(6) The epoxy resin composition according to the above (5), wherein the content of the curing agent is 0.7 equivalent to 1.2 equivalents with respect to 1 equivalent of the epoxy group of the epoxy resin mixture,
(7) Furthermore, the epoxy resin composition as described in said (6) which contains a filler 50 to 90weight% with respect to the total amount of an epoxy resin composition,

(8) An epoxy resin mixture obtained by epoxidizing the phenol resin mixture according to (1) above, and a curing agent of 0.7 equivalents to 1.2 equivalents with respect to 1 equivalent of epoxy groups of the epoxy resin mixture. A cured product obtained by curing an epoxy resin composition containing
(9) An epoxy resin mixture obtained by epoxidizing the phenol resin mixture according to (1) above, 0.7 to 1.2 equivalents of a curing agent with respect to 1 equivalent of epoxy groups of the epoxy resin mixture, and Hardened | cured material which hardened the epoxy resin composition containing 50 to 90 weight% of inorganic fillers with respect to the total amount of an epoxy resin composition,
(10) In the presence of zinc halide, 2-8 equivalents of formaldehyde and hydrogen halide are reacted in the presence of an excess amount of hydrogen halide with respect to 1 mol of biphenyl and biphenyl, and halomethyl of biphenyl is reacted. In the ratio (GC area ratio) to the total reaction product in GC-MS, bishalomethylbiphenyl is 60% or more and less than 80%, and tri (halomethyl) biphenyl and tetra (halomethyl) biphenyl are combined. A reaction product containing 15 to 30% and the remainder of other by-products, and reacting with phenol without purifying the reaction product, a method for producing a phenol resin mixture,
(11) An epoxy resin mixture obtained by reacting the phenol resin mixture obtained by the production method of (10) with 0.8 to 12 equivalents of epihalohydrin with respect to 1 equivalent of a hydroxyl group of the phenol resin mixture. Production method,
(12) An epoxy resin composition containing the phenol resin mixture according to (1) or (2) as a curing agent,
About.

  The phenol resin mixture obtained by the present invention is useful as a raw material for an epoxy resin mixture or an epoxy resin composition that gives a cured product having excellent flame retardancy and moderate storage elastic modulus, and is easy to produce. It is. Moreover, when the epoxy resin mixture or epoxy resin composition of this invention hardens | cures, it can be made into the hardened | cured material which has a flame retardance and a moderate storage elastic modulus as above-mentioned. Therefore, the epoxy resin mixture of the present invention or the epoxy resin composition of the present invention can be used in a wide range of applications including semiconductor sealing materials and printed wiring board substrates.

Hereinafter, the present invention will be described in detail.
First, the halomethylation reaction of biphenyl for obtaining the phenol resin mixture of the present invention will be described.
The halomethylation reaction of biphenyl is a reaction for obtaining a halomethylated product of biphenyl using biphenyl, formaldehydes or equivalent acetals (hereinafter collectively referred to as carbon source), hydrogen halide, catalyst and solvent. Depending on the reaction conditions, the halomethylated product of biphenyl may further react to produce diarylmethane. In general, for example, reference can be made to the chloromethylation reaction described in, for example, 5th edition Experimental Chemistry Course 13 (2) p439 (2005) and SYNTHESIS, 1003 (1991).

For example, according to Patent Document 8 (Japanese Patent Publication No. 54-929), 4,4′-bis (chloromethyl) is obtained by a chloromethylation reaction using biphenyl, paraformaldehyde, hydrogen chloride gas, zinc chloride, and cyclohexane. ) -1,1′-biphenyl can be produced. As another production method, for example, the methods described in JP-A-9-208506, JP-A-10-139699, and Japanese Patent No. 3784865 can be exemplified.
The halomethylation reaction in the present invention comprises the above composition, that is, 60 to 80% by weight of bishalomethylbiphenyl, 15 to 30% in total of tri (halomethyl) biphenyl and tetra (halomethyl) biphenyl, and the remaining other by-products. Any method described above may be used as long as the reaction product can be obtained.
Hereinafter, the halomethylation reaction in the present invention will be described with reference to the reaction example of Patent Document 8, which is the most typical example.

Preferable examples of the methyl group carbon source in the halomethylation include formaldehyde such as formalin, paraformaldehyde, methylal, and trioxane, with paraformaldehyde being preferred.
The charge equivalent of a carbon source (for example, formaldehyde in the reaction example of Patent Document 8) varies depending on the halomethylation rate (the number of halomethyl groups per molecule) relative to biphenyl, but 1 equivalent to 15 to 1 mole of biphenyl. Equivalents are preferable, 1.5 equivalents to 10 equivalents are more preferable, and 2 equivalents to 8 equivalents are still more preferable. If the amount is less than 1 equivalent, the reaction point with biphenyl having a phenolic hydroxyl group may be insufficient. If the amount exceeds 15 equivalents, the reaction point / cross-linking point is too much and the molecular weight becomes too large, or the solid content concentration is increased and stirred. The condition may worsen.

As the halogen source for the halogenation, any of hydrogen halide and any one that generates hydrogen halide by reaction can be used. As the halogen source, hydrogen halide is most commonly used. Preferred examples of the hydrogen halide include hydrogen chloride, hydrogen bromide, and hydrogen iodide, with hydrogen chloride being preferred. These hydrogen halides can be used in the form of a gas. When hydrogen halide is used in the form of a gas, the reaction can be carried out by directly blowing a raw material mixture other than hydrogen halide.
The hydrogen halide can also be dissolved in water, acetic acid or other organic solvents and used as a hydrogen halide solution, but the method using hydrogen chloride in the form of gas is most preferred.
In the halomethylation reaction, in order to obtain a reaction product having the above composition, it is preferable to suppress the formation of methylene-bridged diarylmethane observed as a by-product. It is known that diarylmethane is preferentially produced when the concentration of hydrogen halide in the reaction system is low. In order to suppress the production of the by-product, it is preferable to increase the concentration of hydrogen halide. Therefore, it is desirable to introduce an excessive amount of hydrogen chloride gas into the reaction solution. Examples of the method of introducing an excessive amount of hydrogen chloride gas include a method of introducing hydrogen chloride gas under a pressurized condition or a low temperature condition.

In the reaction, preferred catalysts include sulfuric acid, thionyl chloride, orthophosphoric acid, zinc chloride, aluminum chloride, iron chloride, tin chloride and other Friedel-Crafts type reaction catalysts, tetrabutylammonium bromide, trimethylbenzyl chloride, chloride Quaternary ammonium salts such as cetylpyridinium can be mentioned. Among these, zinc chloride, aluminum chloride, iron chloride, tin chloride, tetrabutylammonium bromide, trimethylbenzyl chloride, and cetylpyridinium chloride are more preferable, and zinc chloride is particularly preferable because it is inexpensive and easy to handle.
These catalysts may be used alone or in combination of two or more.
Although the usage-amount of a catalyst is not specifically limited, The range of 0.01 mol-3 mol with respect to biphenyl is preferable. 0.1 mol-1 mol is more preferable.

The solvent used in the reaction is not particularly limited as long as it is a non-reactive solvent. Preferred solvents include aliphatic hydrocarbon solvents (for example, chain alkanes such as hexane and heptane, cyclic alkanes such as cyclopentane and cyclohexane, and kerosene), aliphatic carboxylic acid solvents (for example, formic acid, acetic acid, propionic acid, etc. ), Aromatic hydrocarbon solvents with low electron density in the aromatic ring (eg chlorobenzene, nitrobenzene, orthodichlorobenzene, trichlorobenzene, etc.), aliphatic halogenated hydrocarbon solvents (eg chloroform, dichloromethane, dichloroethane, tetrachloroethane, etc. organic solvents) Is mentioned.
These solvents may be used alone or in combination of two or more. Preferred examples of the solvent include C5-C6 cyclic alkanes, and the most preferred examples include cyclohexane which is inexpensive and has a low boiling point and can be easily removed.
When zinc chloride is used as a catalyst, an aliphatic alcohol such as 1-pentanol or 1-hexanol, or water may be added in an equimolar amount to the catalyst. These additions are known to increase the solubility of the catalyst and improve the reaction activity in some cases (Bull. Chem. Soc. Jpn. 66, 3520 (1993)). In the present invention, it may not be added in particular.
Although the usage-amount of a solvent is not specifically limited, About 1/2 weight part-10 times weight part of solid content are preferable, and 8 weight part or less is more preferable.

The reaction temperature is not particularly limited as long as it is within an acceptable temperature range for the solvent used. Usually, it is 0 degreeC-100 degreeC, Preferably it is about 15-60 degreeC. When the reaction proceeds at around room temperature, around room temperature is preferred.
In general, methylene-bridged diarylmethane, which is observed as a by-product in the chloromethylation reaction, is known to be preferentially produced when the reaction temperature is high. Therefore, it is preferable to lower the reaction temperature.
The reaction time is not particularly limited. Usually, it can be performed in about 6 to 36 hours.
The charging method is not particularly limited. As a preferred method, raw materials other than hydrogen halide are charged first, and hydrogen halide gas is blown into the system so as to maintain an excessive amount of hydrohalic acid in the system during the reaction. preferable. As the hydrogen halide, hydrogen chloride is preferred.

In the present invention, the composition of the reaction product obtained above is the same as the ratio (GC area ratio) to the total reaction product (total amount) in GC-MS (Gas Chromatograph / Mass Spectrometry), unless otherwise specified. ) Having a bishalomethylbiphenyl (preferably bischloromethylbiphenyl) content of 60% or more and less than 80%, tri (halomethyl) biphenyl (preferably tri (chloromethyl) biphenyl) and tetra (halomethyl) biphenyl (preferably Is preferably a mixture having a total content of tetra (chloromethyl) biphenyl) of 15% to 30% and the other by-products as the remainder (hereinafter also referred to as a mixture of biphenyl compounds having a halomethyl group). Further, the total of the three of bishalomethylbiphenyl, tri (halomethyl) biphenyl and tetra (halomethyl) biphenyl is preferably 75% to 97%, more preferably 80% to 95%.
The main component, bishalomethylbiphenyl, is composed of 4,4′-bishalomethylbiphenyl and its positional isomers. Among bishalomethylbiphenyl, 4,4′-bishalomethylbiphenyl is about 50 to 98%. Preferably, it occupies about 60 to 95%, and the remainder is considered to be its isomer.

The main compounds contained in the reaction product are represented by the formulas of the compounds in the case where the halomethyl group is a chloromethyl group. The “chloromethyl” group in Table A and the “chloromethyl” in the following description can be read as “halomethyl” in the present invention.
4,4′-bischloromethyl-biphenyl represented by Formula 1-3 is a main component in bischloromethylbiphenyl, and accounts for about 50 to 98%, preferably about 60 to 98% of bischloromethylbiphenyl. Conceivable. In bischloromethylbiphenyl, the remainder other than 4,4′-bischloromethyl-biphenyl is considered to be a positional isomer such as 2,4′-bischloromethyl-biphenyl represented by Formula 1-4.

Tri (chloromethyl) biphenyl and tetra (chloromethyl) biphenyl are considered to be composed of, for example, compounds represented by formula 1-5 to formula 1-8 and isomers thereof (substitution isomers).
Examples of other by-products include monochloromethylbiphenyl (for example, compounds represented by Formula 1-1 and Formula 1-2), bisbiphenylylmethane (Formula 1-9), monochloromethyl-bisbiphenylylmethane ( A compound represented by formula 1-10), bischloromethyl-bisbiphenylylmethane (such as a compound represented by formula 1-11), and the like.

The content of bischloromethylbiphenyl with respect to the total amount of the reaction product is 60% or more, less than 80%, and more preferably 65 to 75%.
The total content of tri (chloromethyl) biphenyl and tetra (chloromethyl) biphenyl with respect to the total amount of the reaction product is about 15 to 30%, preferably about 15 to 25%. The proportions of tri (chloromethyl) biphenyl and tetra (chloromethyl) biphenyl vary depending on the reaction conditions and cannot be generally stated. However, the content of trichloromethylbiphenyl with respect to the total amount of the reaction product is about 5% to 25%. 10% to 20% is preferable.
The content of tetra (chloromethyl) biphenyl with respect to the total amount of the reaction product is preferably 1% to 15%, more preferably 2% to 10%.
Of these other by-products, monochloromethylbiphenyl is usually the most common, and the ratio (GC area ratio) to the total reaction product in GC-MS (hereinafter the same unless otherwise specified) is about 1% to 10%. It is.

Next, the reaction of the reaction product obtained above with phenol (also referred to as methylene crosslinking reaction) and the phenol resin mixture of the present invention obtained by the reaction will be described.
The methylene crosslinking reaction is a condensation reaction, and the reaction product (mixture of biphenyl compounds having a halomethyl group) obtained as described above is condensed with phenol. The methylene crosslinking reaction is preferably performed under acidic conditions, for example, at a pH of about 1 to 4.
For example, the reaction can generally refer to the 5th edition, Experimental Chemistry Course 26 (2) p142 (2005).

As described above, the halomethylation reaction product of biphenyl is a mixture, and in the present invention, the mixture is used as it is for a methylene crosslinking reaction with phenol. Therefore, usually, the reaction solution obtained by the halomethylation reaction can be used as it is.
If necessary, the reaction solution can be used as a raw material for the reaction with phenol after being subjected to treatments such as concentration, dilution, degassing, washing with water, neutralization and filtration. Even in that case, it is preferable that it is substantially within the range of the composition of the reaction product.
Usually, it is preferable to use the reaction liquid of the halomethylation reaction of biphenyl as it is for the next methylene crosslinking reaction with phenol.

In the methylene crosslinking reaction, an acid catalyst can be added as necessary, and it is usually preferable to carry out in the presence of an acid catalyst. Various acid catalysts can be used. For example, organic or inorganic acids such as sulfuric acid, p-toluenesulfonic acid, oxalic acid, methanesulfonic acid, trifluoromethanesulfonic acid, zinc chloride, aluminum chloride, iron chloride, chloride. Friedel-Crafts type Lewis acid catalyst such as tin.
Although the usage-amount of these acid catalysts changes with kinds of catalyst, it can add within the range of 0.001-10 times by molar ratio with respect to phenol. Preferably, the amount is about 0.05 to 3 moles.
In a preferred embodiment of the present invention, the reaction solution of the halomethylation reaction is used as it is, and then the condensation reaction is performed. Therefore, the acid catalyst used in the halomethylation reaction can be used as it is, and there is no need to add an acid catalyst again. .
Biphenyl halomethylation reaction product and phenol can be reacted in any proportion. Usually, it is preferable to use 1.5 mol-40 mol of phenol with respect to 1 mol of halomethyl groups in the halomethylation reaction product of biphenyl, more preferably 2 mol-10 mol. If the amount is 1.5 mol or less, there is a concern that the molecular weight will increase, and if it exceeds 40 mol, the pot efficiency will deteriorate.
The amount of phenol added is roughly 0.3 to 2 times (by weight) the total amount of biphenyl, carbon source and acid catalyst added for the halomethylation of biphenyl, preferably The amount is 0.5 to 1.5 times.
In order to trace the reaction, it is preferable to confirm the disappearance of the halomethyl group by analyzing the remaining amount of the halomethyl group. For example, the total amount of saponifiable chlorine can be applied according to the description of JIS K7246. In addition, it can also be traced by performing a pretreatment for reacting a dye or the like as a marker to the halomethyl group of the reactive mixture.

The methylene crosslinking reaction (condensation reaction) can be performed in the absence of a solvent or in the presence of a solvent. Usually, the reaction solution of the halomethylation reaction is preferably used as it is, and the organic solvent mentioned in the section of the halomethylation reaction can be used as it is. Therefore, a preferable solvent can similarly mention C5-C6 cyclic alkane, and a cyclohexane is mentioned as the most preferable thing.
The amount of the solvent used is usually 5 to 300% by weight, preferably 10 to 200% by weight, based on the total weight of the biphenyl halomethylation reaction product and phenol. The reaction temperature of the methylene crosslinking reaction is usually 0 to 120 ° C, preferably about 15 to 100 ° C. The reaction time is usually 1 to 10 hours.

  In the methylene crosslinking reaction, it is most convenient to react by adding phenol to the reaction solution of the halomethylation reaction directly after the halomethylation reaction. If necessary, the reaction solution of the halomethylation reaction can be added to phenol (and optionally a mixture of an acid catalyst and a solvent). Further, if necessary, operations such as dilution, degassing, washing with water and neutralization can be performed before and after the reaction product composition within a range in which the composition of the reaction product is not significantly changed.

After completion of the condensation reaction, the acid catalyst is removed by neutralization, washing with water, etc., and then the solvent used under heating under reduced pressure is removed to take out the desired phenol resin mixture. It is desirable to remove unreacted phenol together with the solvent used under heating and reduced pressure.
In the present invention, the phenol resin mixture obtained by removing the solvent and unreacted phenol after removing the acid catalyst by neutralization, washing with water, etc. after completion of the methylene crosslinking reaction, usually without recrystallization treatment. It is preferable to take it to the next epoxidation reaction.
The reaction solution after completion of the methylene crosslinking reaction can be continued to the next epoxidation step without removing the solvent and unreacted phenol, but in this case, the hydrogen halide and acid catalyst used in the reaction are used in the middle. In order to reconcile, an operation of treating an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide with a base is required. Moreover, since unreacted phenol reacts with epoxidized epichlorohydrin and the like, it cannot be said that it is very preferable.
The phenol resin mixture of the present invention obtained as described above is a phenol resin mixture in which phenol and biphenyl are linked by a methylene crosslinking group (partially biphenyls are linked by methylene crosslinking, and further, phenol is mixed with biphenyl. (Including phenol resins linked by methylene crosslinking), and is useful as a raw material for the epoxy resin mixture of the present invention, and can be used as an epoxy resin mixture through the following epoxidation reaction.

The phenol resin mixture of the present invention obtained as described above has a softening point of 65 to 85 ° C., a number average molecular weight of about 350 to 1,200, preferably about 400 to 1,000, more preferably by GPC (gel permeation chromatography). Is about 450 to 950, most preferably about 500 to 900, and the weight average molecular weight is about 400 to 2000, preferably about 500 to 1700, more preferably about 550 to 1600, and most preferably about 600 to 1000. The OH equivalent is about 160 to 250 g / eq, preferably about 170 to 240 g / eq, and most preferably about 180 to 230 g / eq.
The chemical structure of a typical compound of the phenol resin mixture of the present invention is considered to be F2-1 to F2-6 and the like exemplified below from the analysis result of the reaction product of the halomethylation reaction. N in the formula is about 1 to 10.
The phenol resin mixture of the present invention is, for example, a mixture of linear molecules or branched molecules as is apparent from the following examples.

(F2-1 to F2-3)

(F2-4 to F2-6)

Next, the epoxidation reaction for obtaining the epoxy resin mixture of the present invention will be described.
The epoxy resin mixture of the present invention is an epoxidized product of the phenol resin mixture of the present invention obtained above, and can be obtained by epoxidizing the phenol resin mixture by a reaction with epihalohydrin by a conventional method. More specifically, the following method is mentioned.
As a preferable method of epoxidation, a method of reacting the phenol resin mixture of the present invention with an epihalohydrin in the presence or absence of a solvent in the presence of an alkali metal hydroxide to glycidyl ether can be mentioned. . In this method, the reaction temperature is usually about 10 to 100 ° C, preferably about 30 to 90 ° C. Examples of the epoxidation reaction using the epihalohydrin include an epoxidation reaction described in Japanese Patent No. 3934829, a one-step method and a fusion method described in Japanese Patent Application Laid-Open No. 2007-308642.
In the reaction for obtaining the epoxy resin of the present invention, the alkali metal hydroxide may use an aqueous solution thereof. In that case, the aqueous solution of the alkali metal hydroxide is continuously added to the reaction system, and water and epihalohydrin are continuously distilled off under reduced pressure or normal pressure, followed by liquid separation to remove the water and remove the epihalohydrin. May be a method of continuously returning to the reaction system. Further, in the present invention, since the catalyst used up to the previous step remains without being removed unless specially operated, an operation of neutralizing the alkali metal hydroxide by adding it more than usual. By doing this, the reaction can proceed smoothly.
Further, a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, trimethylbenzylammonium chloride or the like is added to the mixture of the phenol resin mixture of the present invention and epihalohydrin as a catalyst, and 0.5 to 50 ° C to 150 ° C To a halohydrin etherified product of a phenol resin obtained by reacting for ~ 8 hours, a solid or aqueous solution of an alkali metal hydroxide is further added and reacted at 20 ° C to 120 ° C for 1 hour to 10 hours to remove hydrogen halide (ring closure). ).

Preferred examples of the epihalohydrin include epichlorohydrin, epibromohydrin, epiiodohydrin, β-methylepichlorohydrin, α-methylepichlorohydrin, γ-methylepichlorohydrin, industrial In particular, epichlorohydrin is preferable.
The usage-amount of the epihalohydrin used for the said epoxidation reaction is 0.8 equivalent-12 equivalent normally with respect to 1 equivalent of hydroxyl groups of the phenol resin of this invention, Preferably it is 0.9 equivalent-11 equivalent. At this time, in order to make the reaction proceed smoothly, a polar solvent, preferably an alcohol (for example, a C1-C4 alcohol such as methanol or ethanol) or an aprotic polar solvent (for example, dimethylsulfone, dimethylsulfoxide, etc.) is used. It is preferable to add and perform the reaction. The amount of the polar solvent used may be appropriately selected depending on the type of solvent, etc., usually between 2 wt% and 150 wt% with respect to the amount of epihalohydrin. For example, when alcohol is used, the amount used is usually 2% to 20% by weight, preferably 4% to 15% by weight, based on the amount of epihalohydrin. Moreover, when using an aprotic polar solvent, it is 5 to 150 weight% normally with respect to the quantity of epihalohydrin, Preferably it is 10 to 140 weight%.

  Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide, and sodium hydroxide and potassium hydroxide are preferable.

The epoxy resin mixture of the present invention can be obtained by removing the epihalohydrin, the solvent, and the like after the epoxidation reaction is washed with water or without washing with water under reduced pressure.
Further, in order to obtain an epoxy resin mixture with less hydrolyzable halogen, the recovered epoxy resin mixture is dissolved in a solvent such as toluene, methyl isobutyl ketone, etc., and alkali metal water such as sodium hydroxide or potassium hydroxide is dissolved therein. It is preferable to add an aqueous solution of an oxide and react with the hydrolyzable halogen contained in the reaction product to remove the hydrolyzable halogen. This post-treatment can also secure the epoxy ring. The amount of alkali metal hydroxide used in this post-treatment is usually 0.01 equivalents to 0.3 equivalents, preferably 0.05 equivalents to 0.2 equivalents, relative to 1 equivalent of epoxy group in the reaction product. The post-treatment temperature is usually 50 ° C. to 120 ° C., and the reaction time is usually 0.5 hours to 2 hours.
After this post-treatment, the produced salt is removed by filtration, washing with water, etc., and the solvent is distilled off under heating and reduced pressure to obtain the epoxy resin mixture of the present invention.

The epoxy resin mixture of the present invention obtained as described above has a softening point of 50 to 75 ° C, preferably 52 to 65 ° C, more preferably 54 to 60 ° C, and an ICI viscosity of 0.02 to 0.50 Pa · s. , Preferably 0.04 to 0.40 Pa · s, more preferably 0.06 to 0.20 Pa · s, number average molecular weight by GPC (gel permeation chromatography) of about 400 to 1200, preferably about 500 to 1000, More preferably, it is about 600 to 900, most preferably about 600 to 850, and the weight average molecular weight is about 800 to 2000, preferably about 900 to 1800, more preferably about 1000 to 1600, and most preferably about 1000 to 1500. is there. The epoxy equivalent is about 200 to 360 g / eq, preferably about 230 to 340 g / eq, and most preferably about 250 to 310 g / eq.
Typical chemical structures of the epoxy resin mixture in the present invention are exemplified in the following F3-1 to F3-6. Since the epoxy resin mixture of the present invention is a reaction product of the phenol resin mixture of the present invention and epihalohydrin, it becomes a mixture of linear molecules or branched molecules as will be apparent from the following examples.
Note that n in the formula is the same as in F2-1 to F2-6.

(F3-1 to F3-3)

(F3-4 to F3-6)

Next, the epoxy resin composition of the present invention will be described.
If the epoxy resin composition of this invention contains the epoxy resin mixture and hardening | curing agent of this invention, there will be no restriction | limiting in particular in other arbitrary addition components.
For example, in the epoxy resin composition of the present invention, in addition to the epoxy resin mixture of the present invention, another epoxy resin can be used in combination as one of optional components. When used together, the proportion of the epoxy resin mixture of the present invention in the total epoxy resin is preferably 30% by weight or more and 100% by weight or less, more preferably 40% by weight or more and 100% by weight or less, and still more preferably 50%. % By weight or more and 100% by weight or less. From the viewpoint of sufficiently achieving the characteristics of the epoxy resin mixture of the invention, in particular, excellent flame retardancy in a cured product and adequate storage elastic modulus, the epoxy resin mixture of the invention is preferably 60% by weight or more, more preferably 70% by weight. Or more, more preferably 80% by weight or more, and most preferably 90% by weight or more. The upper limit is up to 100% by weight.

Examples of other epoxy resins that can be used in combination with the epoxy resin mixture of the present invention include novolac type epoxy resins, bisphenol A type epoxy resins, and triphenylmethane type epoxy resins.
Specifically, glycidyl etherified products of aromatic compounds having 2 to 4 hydroxyl groups {for example, bisphenol A, bisphenol F, bisphenol S, fluorenylidene diphenol, terpene diphenol, 4,4'-biphenol, 2, 2'-biphenol, 3,3'-5,5'-tetramethyl- [1,1'-biphenyl] -4,4'-diol, hydroquinone, resorcin, naphthalenediol, tris- (4-hydroxyphenyl) methane 1,1,2,2-tetrakis (4-hydroxy) ethane}; or phenols (phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.) and aldehydes or ketones, or they Reactive derivatives of {e.g. formaldehyde, Cetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, o-hydroxybenzaldehyde, p-hydroxyacetophenone or 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) benzene, etc.} Glycidyl etherification product of modified polycondensate; glycidyl etherification product derived from halogenated bisphenols or alcohols such as tetrabromobisphenol A; alicyclic epoxy resin; glycidylamine epoxy resin; glycidyl ester epoxy resin ;etc Solid or liquid epoxy resins. These may be used alone or in combination of two or more. Moreover, epoxy resins other than these can also be used in combination.

In the epoxy resin composition of the present invention, the phenol resin mixture of the present invention can be used as a curing agent alone or in combination with other curing agents. When used in combination, the proportion of the phenol resin mixture of the present invention in the total curing agent is preferably 30% by weight or more, particularly preferably 40% by weight or more. The upper limit is 100% by weight.
Examples of the curing agent used in the epoxy resin composition of the present invention include amine compounds, acid anhydride compounds, amide compounds, and phenol compounds. Specific examples include amine compounds such as diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, trifluoroborane-amine complex; polyamide resins synthesized from dicyandiamide, dimer of linolenic acid and ethylenediamine, etc. Amide compounds; phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, etc. Acid anhydride compounds; phenols having 2 to 4 hydroxyl groups {bisphenol A, bisphenol F, bisphenol S, fluorenylidene diphenol, terpene diphenol, 4,4'-bifu Enol, 2,2′-biphenol, 3,3′-5,5′-tetramethyl- [1,1′-biphenyl] -4,4′-diol, hydroquinone, resorcin, 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. Benzene or naphthalene having a hydroxyl group, which may have an alkyl substitution, and the alkyl group is preferably C1-C4 alkyl) and an aldehyde or ketone (formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, o-hydroxybenzaldehyde, p − A polycondensate with droxyacetophenone, o-hydroxyacetophenone}, or a reactive derivative of the above phenols and aldehyde or ketone {dicyclopentadiene, furfural, 4,4′-bis (chloromethyl) -1,1 ′ Polycondensates with -biphenyl, 4,4'-bis (methoxymethyl) -1,1'-biphenyl, 1,4-bis (chloromethyl) benzene, 1,4-bis (methoxymethyl) benzene, etc.} And modified compounds of these polycondensates, and phenol compounds such as tetrabromobisphenol A; imidazole; guanidine derivatives; and the like, but are not limited thereto.
These may be used alone or in combination of two or more.
Among these curing agents, a phenol compound or an amine compound is preferable, and a phenol compound, further a phenol aralkyl resin, or a phenol resin mixture of the present invention is preferable. Most preferred is phenol aralkyl resin.

  In the epoxy resin composition of the present invention, the amount of the curing agent used is the equivalent of the active group that reacts with the epoxy of the curing agent with respect to 1 equivalent of the epoxy group of the epoxy resin (hydroxyl equivalent in the phenol compound, amino group in the amine compound). Equivalents), preferably 0.7 equivalents to 1.2 equivalents. When the active group equivalent of the curing agent is less than 0.7 equivalent to 1 equivalent of epoxy group, or exceeds 1.2 equivalent, there is a possibility that curing will be incomplete and good cured properties will not be obtained. is there.

  In the epoxy resin composition of the present invention, a curing accelerator may be used. Specific examples of the curing accelerator that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole; 2- (dimethylaminomethyl) phenol, 1,8-diaza-bicyclo Tertiary amines such as (5,4,0) undecene-7; phosphines such as triphenylphosphine; metal compounds such as tin octylate and the like. Although a hardening accelerator does not need to be used, when using, 0.1 weight part-5.0 weight part with respect to 100 weight part of epoxy resins can be used suitably as needed.

  An inorganic filler (also referred to as a filler) can be added to the epoxy resin composition of the present invention as necessary. Inorganic fillers include powders such as crystalline silica, fused silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, fosterite, steatite, spinel, titania, talc, etc. Examples thereof include, but are not limited to, spherical beads. These may be used alone or in combination of two or more. The content of these inorganic fillers is 0 to 95% by weight, preferably 20% to 95% by weight, more preferably 50% to 95% by weight, still more preferably 70% by weight based on the total amount of the epoxy resin composition. % To about 95% by weight, most preferably 70% to 90% by weight.

  Furthermore, in the epoxy resin composition of the present invention, if necessary, a release agent such as silane coupling agent, stearic acid, palmitic acid, zinc stearate, calcium stearate; coloring of carbon black, phthalocyanine blue, phthalocyanine green, etc. Agents: polybutadiene, modified products thereof, modified products of acrylonitrile copolymer, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide compound, cyanate resin (or prepolymer thereof), silicone gel, silicone oil and other resins Etc. Additives such as may be added.

More specifically, the preferred epoxy resin composition of the present invention is as follows.
(1) The epoxy resin mixture of the present invention and a curing agent, and 0.7 to 1.2 equivalents of the curing agent in terms of active group equivalent to the epoxy group of the curing agent with respect to 1 equivalent of the epoxy group of the epoxy resin. An epoxy resin composition comprising the epoxy resin mixture of the present invention in an amount of 4 to 80% by weight with respect to the total amount of the epoxy resin composition, with the balance being optional additive components.
(2) The epoxy resin composition according to the above (1), wherein the optional additive component is an inorganic filler and contains 50% to 95% by weight, preferably 70% to 90% by weight, based on the total amount of the epoxy resin composition. .
(3) The epoxy according to the above (2), wherein the epoxy resin mixture of the present invention is 5% by weight to 30% by weight and the balance is the inorganic filler with respect to the total amount of the epoxy resin mixture of the present invention and the inorganic filler. Resin composition.
(4) The above-mentioned (1) to (3), wherein the optional additive component is either one or both of a mold release agent and a coupling agent, and 0.05 wt% to 1 wt% with respect to the total amount of the epoxy resin composition ) Epoxy resin composition.
(5) The epoxy resin mixture of the present invention has a softening point of 52 to 65 ° C., an ICI viscosity of 0.04 to 0.40 Pa · s, a number average molecular weight of 400 to 1200 and weight by GPC (gel permeation chromatography). The epoxy resin composition according to any one of (1) to (4), wherein the average molecular weight is 800 to 2000 and the epoxy equivalent is 200 to 360 g / eq.

(6) The epoxy resin mixture of the present invention is obtained by a halomethylation reaction of biphenyl, and is a ratio (GC area ratio) to the total reaction product in GC-MS, with bishalomethylbiphenyl being 60% or more and 80%. A phenol resin mixture obtained by a methylene cross-linking reaction of phenol with a reaction product containing less 15 to 30% in total of tri (halomethyl) biphenyl and tetra (halomethyl) biphenyl and the other by-products, The epoxy resin composition according to the above (1) to (5), which is an epoxy resin mixture obtained by epoxidation.
(7) The phenol resin mixture has a softening point of 65 to 85 ° C., a GPC (gel permeation chromatography) number average molecular weight of 350 to 1200, a weight average molecular weight of 400 to 2000, and an OH equivalent of 160 to 250 g / eq. The epoxy resin composition according to (6) above.
(8) The epoxy resin composition according to the above (1) to (7), wherein the curing agent is a phenol compound.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the epoxy resin mixture of the present invention, a curing agent, and optional additive components. The epoxy resin composition of the present invention can be easily made into a cured product by a method similar to a conventionally known method.
More specifically, first, for example, selected from the group consisting of the epoxy resin mixture of the present invention and a curing agent, and if necessary, optional additional components (for example, a curing accelerator, an inorganic filler, a coupling agent, and a release agent). And the like are sufficiently mixed until they become uniform using, for example, an extruder, a kneader, a roll or the like to obtain the epoxy resin composition of the present invention. Next, after the obtained epoxy resin composition is melted, it is molded by using a casting or transfer molding machine, an injection molding machine, a casting machine or the like, and more preferably at 80 to 200 ° C. at 2 to 80 ° C. The cured product of the epoxy resin composition of the present invention can be obtained by heating for 16 hours.

  Further, the viscosity of the epoxy resin composition of the present invention is lowered by heating or melting, or the viscosity is lowered by mixing a solvent with the epoxy resin composition, and the resulting mixture is made of glass fiber, carbon fiber, polyester fiber, polyamide. It is also possible to obtain a cured product by hot press molding a prepreg obtained by impregnating a substrate such as fiber, alumina fiber or paper and heating and semi-drying. Examples of the solvent include aromatic solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylimidazolide. Amide solvents such as non; Sulfone solvents such as dimethyl sulfoxide and tetramethylene sulfone; Lactam solvents such as N-methylpyrrolidone; Lactone solvents such as γ-butyrolactone; Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, Examples of the solvent include ether solvents such as propylene glycol monomethyl ether monoacetate and propylene glycol monobutyl ether.

The solvent used above may be a single solvent or a mixed solvent of two or more. In addition, when the solvent is mixed in the above, the amount occupying usually 10 wt% to 70 wt%, preferably 15 wt% to 70 wt% with respect to the total amount of the mixture of the epoxy resin composition of the present invention and the solvent. Use.
The above-mentioned prepreg is cut into a desired shape, and if necessary, laminated with a copper foil or the like, and then cured by heating under pressure by a method such as a press molding method, an autoclave molding method, or a sheet winding molding method, Or it can be set as the laminated board which has this hardened | cured material. In addition, a circuit is formed on a laminated plate made by stacking copper foil on the surface, and the prepreg and copper foil are stacked thereon, or a copper foil having the prepreg is stacked to form a circuit, and necessary Accordingly, the operation can be repeated to obtain a multilayer circuit board.

  As a semiconductor device that can be manufactured by sealing a semiconductor element (semiconductor chip) with the epoxy resin composition of the present invention, for example, DIP (dual inline package), QFP (quad flat package), BGA (ball grid array) ), CSP (chip size package), SOP (small outline package), TSOP (thin small outline package), TQFP (think quad flat package), and the like. In the field of optical semiconductors, there are encapsulated optical semiconductor elements (semiconductor chips) such as light emitting diodes (LEDs), phototransistors, CCDs (charge coupled devices), and EPROMs such as UV-EPROMs.

The epoxy resin composition of the present invention can be used as a photo-thermosetting resin composition by mixing with a compound having an ethylenically unsaturated group. In the epoxy resin composition of the present invention, the composition further comprises a compound having an ethylenically unsaturated group, preferably a crosslinker (B), photopolymerization, in addition to the alkaline aqueous solution-soluble resin (A), as an optional additive component. Contains initiator (C).
In such a photocurable resin composition, the content of the epoxy resin mixture of the present invention is usually 1% to 50% by weight, preferably 2% to 30% by weight.
Each component of the photocurable resin composition containing the epoxy resin mixture of the present invention will be described more specifically below.

  An aqueous alkali solution-soluble resin (A); for example, an epoxycarboxylate compound obtained by reacting an epoxy compound having two or more epoxy groups in a molecule with a monocarboxylic acid compound having an ethylenically unsaturated group in the molecule; Reaction products with polybasic acid anhydrides, and more specifically, KAYARAD CCR-1159H, KAYARAD PCR-1169H, KAYARAD TCR-1310H, KAYARAD ZFR-1401H, KAYARAD ZAR-1395H (all Nippon Kayaku Co., Ltd.) Manufactured) and the like.

  Crosslinking agent (B); compounds having an ethylenically unsaturated group, such as acrylates and methacrylate compounds, and specific examples include KAYARAD HX-220, KAYARAD HX-620, KAYARAD DPHA, KAYARAD DPCA-60 (all Nippon Kayaku Co., Ltd.).

  Photopolymerization initiator (C); for example, benzoins, acetophenones, anthraquinones, thioxanthones, ketals, benzophenones, phosphine oxides, etc., specifically KAYACURE DETX-S (manufactured by Nippon Kayaku Co., Ltd.) ), Irgacure 907 (Ciba Specialty Chemical) and the like.

  Furthermore, various additives, for example, fillers such as talc, barium sulfate, aluminum hydroxide, aluminum oxide, silica and clay; thixotropic agents such as aerosil; coloring such as phthalocyanine blue, phthalocyanine green and titanium oxide Agents; silicones, fluorine-based leveling agents and antifoaming agents; polymerization inhibitors such as hydroquinone and hydroquinone monomethyl ether can be added for the purpose of enhancing various performances of the composition.

  The photocurable resin composition can contain a solvent as needed. Usable solvents include, for example, ketones such as acetone, methyl ethyl ketone, and cyclohexanone; aromatic hydrocarbons such as benzene, toluene, xylene, and tetramethylbenzene; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, Glycol ethers such as dipropylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether; ethyl acetate, butyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether acetate, glutar Dialkyl acid, dialkyl succinate, dialkyl adipate, etc. Esters; cyclic esters such as γ-butyrolactone; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc., but these may be used alone or in combination of two or more. May be.

  The photo-curable resin composition containing the epoxy resin mixture of the present invention is useful as a resist material such as an insulating material between electronic components, an optical waveguide connecting optical components, a solder resist for printed circuit boards, and a coverlay. Besides, it can also be used as a color filter, printing ink, sealant, paint, coating agent, adhesive.

  The photocurable resin composition containing the epoxy resin mixture of the present invention can be cured by irradiation with energy rays such as ultraviolet rays. Curing by irradiation with energy rays such as ultraviolet rays can be performed by a conventional method. For example, in the case of irradiating ultraviolet rays, an ultraviolet generator such as a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, or an ultraviolet light emitting laser (such as an excimer laser) may be used.

The photocurable resin composition containing the epoxy resin mixture of the present invention is, for example, a resist film, an interlayer insulating material for a build-up method, or an optical waveguide as a printed board, an electric / electronic / optical substrate such as an optoelectronic board or an optical board. Used for materials. Specific articles using these include, for example, computers, home appliances, portable devices, and the like. Specifically, for example, when manufacturing a printed wiring board constituting a printed circuit board, when using a liquid resin composition, first, a screen printing method, a spray method, a roll coating method, an electrostatic coating method, a curtain is applied to the printed wiring board. The photocurable resin composition containing the epoxy resin of the present invention is applied with a film thickness of 5 to 160 μm by a coating method or the like, and the coating film is usually dried at 50 to 110 ° C., preferably 60 to 100 ° C. As a result, a coating film is formed. Thereafter, the coating film is directly or indirectly irradiated with high energy rays such as ultraviolet rays with an intensity of about 10 to 2000 mJ / cm ² through a photomask having an exposure pattern such as a negative film, and the unexposed portion is described later. Using the liquid, development is performed, for example, by spraying, rocking dipping, brushing, scrubbing, or the like. Thereafter, if necessary, further ultraviolet irradiation is performed, and then heat treatment is usually performed at a temperature of 100 to 200 ° C., preferably 140 to 180 ° C., so that the gold plating property is excellent, and heat resistance, solvent resistance, acid resistance, A printed wiring board having a permanent protective film that satisfies various properties such as adhesion and flexibility can be obtained.

  Examples of the developer include potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium phosphate, potassium phosphate, and other inorganic alkaline aqueous solutions, tetramethyl ammonium hydroxide, tetraethyl Organic alkaline aqueous solutions such as ammonium hydroxide, tetrabutylammonium hydroxide, monoethanolamine, diethanolamine, and triethanolamine can be used.

Hereinafter, the present invention will be described in more detail with reference to examples.
In the following, the physical properties of the resin were measured by the following methods.
・ Measurement of softening point: measured by a method according to JIS K-7234 ・ Measurement of GC-MS (gas chromatography-mass spectrometry) Model: 5975 inert MSD (manufactured by Agilent)
Column: HP-5MS 15m-0.25mm-0.25μm
Carrier gas: Helium 1.0 mL / min (Constant flow mode)
Oven: 50 ° C (2min) -10 ° C / min-300 ° C (23min)
Injection: 1 μl, Split (30: 1), 300 ° C.
Ion source: EI
Measurement model of SEM-EDS (Scanning Electron Microscopy-Energy Disperse Spectroscopy): JED-2140 (manufactured by JEOL)
Acceleration voltage: 20 kV
Working distance: 10mm
Measurement of number average molecular weight and weight average molecular weight by GPC (gel permeation chromatography) Column: Shodex KF-801, KF-802, KF-802.5, KF-803 manufactured by Showa Denko KK
Column temperature: 40 ° C
Injection volume: 0.02 mL
Liquid feeding amount: 1.0 mL / min
Detector: RI
Solvent: Tetrahydrofuran Viscosity measurement: measured at 150 ° C. using an ICI viscometer (Cordix Co., Ltd.) OH equivalent measurement: average mass number of compounds per OH group, according to JIS K-0070 Measured by acetylation method according to the same method. Measurement of epoxy equivalent: Average mass number of the compound per epoxy group, measured according to JIS K-7236, DMA (dynamic viscoelasticity measurement) analysis: DMA 2980 manufactured by TA Instruments (Dynamic viscoelasticity measuring machine) Tg and the storage elastic modulus at 250 ° C. were measured using a frequency of 10 Hz.

Example 1
(1) Chloromethylation reaction of biphenyl Cyclohexane 200 mL, biphenyl 77.05 g, paraformaldehyde 33.55 g, and zinc chloride 46.38 g were charged into a glass 300 mL flask equipped with a stirrer, a thermometer, and a condenser. While vigorously stirring them, hydrogen chloride gas was blown into them vigorously and reacted until a homogeneous solution was obtained. Meanwhile, the liquid temperature was kept at 50 ° C. The liquid temperature was further lowered by 30 ° C., hydrogen chloride gas was blown in for 24 hours, and the reaction was continued to obtain a reaction liquid.
A small amount of the resulting reaction solution was taken and subjected to GC-MS measurement as a dichloromethane solution. As a result, 2.5% mono (chloromethyl) biphenyl, 72.0% bischloromethylbiphenyl, 14.9% tri (chloromethyl) biphenyl, and 5.8% tetra (chloromethyl) biphenyl were detected. Other by-products other than mono (chloromethyl) biphenyl are penta (chloromethyl) biphenyl 0.3%, bisbiphenylylmethane 0.5%, monochloromethyl-bisbiphenylylmethane 1.1%, bis Chloromethyl-bisbiphenylylmethane 0.6% was detected. Furthermore, 2.3% (all GC area%) was detected as other by-products including components for which no compound could be specified.
Also, zinc element (Zn) was detected from elemental analysis using SEM-EDS (Scanning Electron Microscopy / Energy Dispersive Spectroscopy) from the insoluble matter produced when the reaction solution was made into a dichloromethane solution for GC-MS measurement. It was.

(2) Reaction of chloromethylation reaction product and phenol Subsequently, 157.77 g of phenol was added to the reaction solution obtained in (1) above, and the mixture was stirred at room temperature for 2 hours. After deaeration of the reaction vessel, the temperature was raised to 180 ° C. over 10 hours under reduced pressure, and the solvent cyclohexane and unreacted phenol were distilled off.
As a result, 181.5 g of the phenol resin mixture of the present invention was obtained. The resin mixture had a softening point of 74.9 ° C., a number average molecular weight of 513 by GPC (gel permeation chromatography), a weight average molecular weight of 639, and an OH equivalent of 215 g / eq.
The composition of the phenol resin mixture is 72% bischloromethylbiphenyl-derived component (F2-1), trichloromethylbiphenyl-derived component (previously described above) than the composition of the chloromethylation reaction product of biphenyl obtained in (1) above. F2-2) is estimated to be 15%, tetrachloromethylbiphenyl-derived component (said F2-3) 6%, and other components (said F2-4, F2-5, F2-6, etc.) 7%.

Example 2
Synthesis of epoxy resin mixture In a glass 300 mL flask equipped with a stirrer, a thermometer, and a condenser, 26.3 g of the phenol resin mixture of the present invention obtained in Example 1, 52.0 g of epichlorohydrin, 8.6 g of dimethyl sulfoxide, 12.3 g of 30% by weight aqueous sodium hydroxide solution was added and mixed with stirring at 45 ° C. for 1 hour. Next, 3.95 g of flaky sodium hydroxide was added in portions, and the mixture was stirred at 45 ° C. for 2 hours and at 70 ° C. for 1 hour. Methyl isobutyl ketone was added to the obtained reaction solution for dilution, and then water was added to perform water washing by liquid / liquid separation. To the obtained organic layer, 0.93 g of a 30 wt% aqueous sodium hydroxide solution was added and stirred at 70 ° C. for 1 hour. Again, water washing by liquid / liquid separation was performed in the same manner as described above. The obtained reaction solution was concentrated to obtain 20.5 g of the epoxy resin mixture of the present invention.
The obtained resin mixture had a softening point of 57.6 ° C., an ICI viscosity of 0.11 Pa · s, an epoxy equivalent of 292 g / eq, a number average molecular weight of 668 by GPC (gel permeation chromatography), and a weight average molecular weight of 1187.
The composition of the epoxy resin mixture is 72% bischloromethylbiphenyl-derived component (F3-1), trichloromethylbiphenyl-derived component (F3-), based on the composition of the biphenyl chloromethylation reaction product obtained in (1) above. 2) It is estimated that 15%, tetrachloromethylbiphenyl-derived component (F3-3) 6%, and other components (F3-4, F3-5, F3-6, etc.) 7%.

Example 3 and Comparative Example 1
Preparation of flame retardant resin composition and evaluation of cured product thereof Epoxy resin mixture of the present invention obtained in Example 2 or, as a comparative example, phenol-biphenyl aralkyl type epoxy resin NC-3000 (softening point) manufactured by Nippon Kayaku Co., Ltd. 57.4 ° C., ICI viscosity 0.08 Pa · s, epoxy equivalent 277 g / eq, number average molecular weight 793 by GPC, weight average molecular weight 1229) were used to prepare a flame retardant resin composition having the composition shown in Table 1 below. The cured product was obtained by molding at 175 ° C. using a transfer molding machine.

Table 1
Example 3 Comparative Example 1
Epoxy resin (Epoxy resin mixture of Example 2) (NC-3000)
6.17g 6.17g
Curing agent (XLC-3L) 3.6 g 3.8 g
Curing catalyst (TPP) 0.105 g 0.105 g
Filler (MSR-2212) 50.2 g 51.2 g
Mold release agent (Carnauba No. 1) 0.18 g 0.19 g
Coupling agent (KBM-303) 0.20g 0.20g

(note)
XLC-3L: Phenol aralkyl resin, TPP manufactured by Mitsui Chemicals Co., Ltd .: Triphenylphosphine MSR-2212: Cyclos MSR-2212 Carnauba No. 1 manufactured by Tatsumori Co., Ltd. Coupling agent Shin-Etsu Chemical Co., Ltd.

Table 2 shows the results of evaluating the flame retardancy and the storage elastic modulus at 250 ° C. of the cured product thus obtained based on the following method.
-Measurement of flame retardancy: The flame retardancy test was performed according to UL-94, and the total burning time (time until self-digestion) was measured for a test piece (cured product) having a thickness of 0.8 mm.
Measurement of storage elastic modulus at 250 ° C .: Tg and storage elastic modulus at 250 ° C. were measured using DMA 2980 (dynamic viscoelasticity measuring machine) manufactured by TA Instruments using a frequency of 10 Hz.

Table 2
Example 3 Comparative Example 1
Total combustion time (sec) 32 (V-0) 35 (V-0)
Storage elastic modulus (MPa, 250 ° C.) 933 2218
Tg (glass transition point: ° C.) 136 146

The epoxy resin composition containing the epoxy resin mixture of the present invention is excellent in flame retardancy, equivalent to or higher than NC-3000, which is widely used as an excellent flame retardant resin, and moreover, The storage elastic modulus at a high temperature of 250 ° C., which is higher than the glass transition point, is in the range of 500 to 1000 MPa, which is considered preferable for solder crack resistance, compared with the value of NC-3000 of 2000 MPa or more, It can be seen that this also has excellent properties.
The epoxy resin mixture of the present invention has excellent properties as described above, can be produced consistently from biphenyl, and is easy to produce.

Example 4
(1) Chloromethylation reaction of biphenyl Cyclohexane 200 mL, biphenyl 154 g, paraformaldehyde 66 g, and zinc chloride 93 g were charged into a glass 1000 mL flask equipped with a stirrer, a thermometer, and a condenser. While stirring them, hydrogen chloride gas was strongly blown into them and reacted until a uniform solution was obtained. Meanwhile, the temperature was maintained at 30 ° C. Thereafter, hydrogen chloride gas was further blown for 10 hours at 50 ° C., and the reaction was continued to obtain a reaction solution.
A part of the reaction solution was taken and subjected to LC measurement as an N, N′-dimethylformamide solution. As a result, 8.1% monochloromethylbiphenyl, 68.2% bischloromethylbiphenyl, tri (chloromethyl) biphenyl and tetra ( Chloromethyl) biphenyl was combined to detect 18.2% (LC area%).
(2) Reaction of chloromethylation reaction product and phenol Subsequently, 301 g of phenol was added to the reaction solution obtained in (1) above, and the mixture was stirred at 70 ° C. for 2 hours. While raising the temperature to 180 ° C. under reduced pressure, the solvent cyclohexane and unreacted phenol were distilled off.
As a result, 329 g of the phenol resin mixture of the present invention was obtained.
The resin mixture had a softening point of 79.6 ° C., a number average molecular weight of 855 by GPC (gel permeation chromatography), a weight average molecular weight of 1332, and an OH equivalent of 196 g / eq.
The composition of the phenol resin mixture is 8% monochloromethylbiphenyl, 68% bischloromethylbiphenyl-derived component (F2-1) and tri (chloro) than the composition of the chloromethylation reaction product obtained in (1) above. It is estimated that 18% is contained in total of the component derived from methyl) biphenyl (F2-2) and the component derived from tetra (chloromethyl) biphenyl (F2-3 etc.).

Example 5
Synthesis of Epoxy Resin Mixture A glass 1000 mL flask equipped with a stirrer, a thermometer, and a condenser was mixed with 196 g of the phenol resin mixture of the present invention obtained in Example 4, 555 g of epichlorohydrin, and 29.6 g of methanol. While stirring the mixture at 70 ° C., 42 g of flaky sodium hydroxide was added in portions. Thereafter, the mixture was further stirred at 70 ° C. for 1 hour. After adding 150 g of water to the resulting reaction solution and mixing, the mixture was allowed to stand and the lower aqueous layer separated into two layers was removed. Unreacted epichlorohydrin was distilled off from the reaction solution after washing with water. Methyl isobutyl ketone was added thereto for dilution, and then 13.3 g of a 30 wt% aqueous sodium hydroxide solution was added and stirred at 70 ° C. for 1 hour. Water was added thereto, followed by washing with liquid / liquid separation. The reaction solution after washing with water was concentrated to obtain 215 g of the epoxy resin mixture of the present invention.
The epoxy mixture had a softening point of 56.5 ° C., an ICI viscosity of 0.11 Pa · s, an epoxy equivalent of 264 g / eq, a number average molecular weight of 803 by GPC (gel permeation chromatography), and a weight average molecular weight of 1419.
The composition of the epoxy resin mixture was 8% monochloromethylbiphenyl-derived component, bischloromethylbiphenyl-derived component (structural formula: F3-1), based on the composition of the chloromethylation reaction product obtained in Example 4 (1) above. Etc.) and 68% and a component derived from tri (chloromethyl) biphenyl (structural formula: F3-2 etc.) and a component derived from tetra (chloromethyl) biphenyl (structural formula: F3-3 etc.) are estimated to contain 18%. Is done.

Example 6
In the same manner as in Example 3, the epoxy resin mixture of the present invention obtained in Example 5 was prepared into a flame retardant resin composition having the composition shown in Table 3 below, and molded with a transfer molding machine to obtain a cured product. It was.

Table 3
Example 6
Epoxy resin (epoxy resin mixture of Example 5)
12g
Curing agent (XLC-3L) 7.7 g
Curing catalyst (TPP) 0.204g
Filler (MSR-2212) 100.8g
Release agent (Carnauba No.1) 0.36g
Coupling agent (KBM-303) 0.40g

  With respect to the obtained cured product, flame retardancy and storage modulus were measured in the same manner as shown in Example 3. The results are shown in Table 4.

Table 4
Example 6
Total combustion time (sec) 35 (V-0)
Storage elastic modulus (MPa, 250 ° C.) 608
Tg (° C) 145

Example 7
500 g of the phenol resin mixture of the present invention obtained in the same manner as in Example 4 was dissolved in 1000 ml of methyl isobutyl ketone, the insoluble matter was filtered, water was added thereto, and water washing was performed by liquid / liquid separation. It was. As a result, a phenol resin mixture (referred to as EX7PhnolMix) having a hydroxyl group (OH) equivalent of 204 g / eq was obtained.
The obtained epoxy resin mixture is used as a curing agent, and the epoxy resin of the present invention having the composition shown in Table 5 below is used as the epoxy resin, using the above-mentioned Nippon Kayaku Co., Ltd. phenol-biphenyl aralkyl epoxy resin NC-3000. A composition was prepared and molded with a transfer molding machine to obtain a cured product.

Table 5
Example 7
Epoxy resin (NC-3000) 18g
Curing agent (EX7PhnolMix) 13.3g
Curing catalyst (TPP) 0.45g
Filler (MSR-2212) 160.8g
Release agent (Carnauba No.1) 0.58g
Coupling agent (KBM-303) 0.64g

  With respect to the obtained cured product, flame retardancy and storage modulus were measured in the same manner as shown in Example 3. The results are shown in Table 6 below.

Table 6
Example 7
Total combustion time (sec) 27
Storage elastic modulus (250 ° C.) (MPa) 449
Tg (° C) 147

Example 8 and Comparative Example 2
Using the phenol resin mixture (EX7PhnolMix) of the present invention obtained in Example 7 as a curing agent and using the above-mentioned Nippon Kayaku Co., Ltd. phenol-biphenylaralkyl type epoxy resin NC-3000, the following Table 7 The epoxy resin composition (EX8 EPOXY COM) of the present invention having the composition shown in FIG.
On the other hand, as Comparative Example 2, as a curing agent, instead of the phenol resin mixture of the present invention (EX7 PhnolMix), a phenol-biphenylaralkyl type phenol resin GPH-65 (OH equivalent 199 g / eq, softening point 65. 1 ° C) was used to prepare a comparative epoxy resin composition (Comparative Example 2) (CPA2 EPOXY COM) shown in Table 7 below.
The epoxy resin composition prepared above was roll-kneaded to obtain an epoxy resin composition for evaluation.

Table 7
EX8 EPOXY COM CPA2 EPOXY COM
Epoxy resin (NC-3000) 15g 15g
Curing agent EX7PhenolMix 11g −
GPH-65-10.8g
Curing catalyst (TPP) 0.315 g 0.405 g
Filler (MSR-2212) 156g 155g
Mold release agent (Carnauba No.1) 0.55g 0.55g
Coupling agent (KBM-303) 0.62g 0.62g

As evaluation of curability of the epoxy resin composition obtained above, the maximum value of torque was measured with a curast meter manufactured by JSR Corporation.
Further, as an evaluation of fluidity, spiral flow was measured under the conditions of 175 ° C. and a molding pressure of 70 kg / cm ² (based on ASTM F3133). The results are shown in Table 8.

Table 8
EX8 EPOXY COM CPA2 EPOXY COM
Curast torque (N · m) 10.5 9.3
Spiral flow (inch, n = 5) 33.5 30.7
Gel time (sec) 29.4 29.6

Since the curast torque, which is an index of curability, indicates that the greater the value is, the stronger the cure is, the more the epoxy resin composition of Example 8 is more curable than the epoxy resin composition of Comparative Example 2. Show.
In addition, in the epoxy resin composition having the same gel time, the longer the spiral flow that is the index of fluidity, the higher the fluidity. Therefore, the epoxy resin composition of Example 8 is the epoxy resin of Comparative Example 2. It shows that the composition is excellent in fluidity.

The cured product of the epoxy resin composition containing the epoxy resin mixture of the present invention is not only excellent in flame retardancy, but also has a storage elastic modulus at 250 ° C. within a certain range as compared with the conventional flame retardant epoxy resin cured product, Since it is reduced, it also has excellent resistance to solder cracks, and the epoxy resin mixture of the present invention and the epoxy resin composition containing it are suitable as electrical and electronic materials around semiconductors such as semiconductor sealing materials and printed wiring boards. ing.
Further, the phenol resin mixture of the present invention is an intermediate raw material for the epoxy resin mixture of the present invention having the above-mentioned excellent properties, and can be produced without isolating and purifying the intermediate halomethylbiphenyl. It is easy to manufacture and has high industrial utility.

Claims (12)

  It is obtained by halomethylation reaction of biphenyl, and in a ratio (GC area ratio) to the total reaction product in GC-MS, bishalomethylbiphenyl is 60% or more and less than 80%, and tri (halomethyl) biphenyl and tetra ( A phenol resin mixture obtained by a methylene crosslinking reaction of phenol with a reaction product containing 15 to 30% in total of halomethyl) biphenyl and the other by-products.   The phenol according to claim 1, having a softening point of 65 to 85 ° C, a GPC (gel permeation chromatography) number average molecular weight of 350 to 1200, a weight average molecular weight of 400 to 2000, and an OH equivalent of 160 to 250 g / eq. Resin mixture.   The epoxy resin mixture obtained by epoxidizing the phenol resin mixture of Claim 1 or 2.   Softening point 50-75 ° C., ICI viscosity 0.02-0.50 Pa · s, number average molecular weight by GPC (gel permeation chromatography) 400-1200, weight average molecular weight 800-2000, epoxy equivalent 200 The epoxy resin mixture according to claim 3, which is ˜360 g / eq.   An epoxy resin composition comprising the epoxy resin mixture according to claim 3 and a curing agent.   The epoxy resin composition according to claim 5, wherein the content of the curing agent is 0.7 to 1.2 equivalents with respect to 1 equivalent of epoxy groups in the epoxy resin mixture.   Furthermore, the epoxy resin composition of Claim 6 which contains a filler 50 to 90weight% with respect to the total amount of an epoxy resin composition.   An epoxy resin mixture obtained by epoxidizing the phenol resin mixture according to claim 1 and an epoxy resin containing 0.7 to 1.2 equivalents of a curing agent with respect to 1 equivalent of epoxy groups of the epoxy resin mixture. A cured product obtained by curing the composition.   An epoxy resin mixture obtained by epoxidizing the phenol resin mixture according to claim 1, 0.7 to 1.2 equivalent of a curing agent and an epoxy resin composition with respect to 1 equivalent of an epoxy group of the epoxy resin mixture. Hardened | cured material which hardened the epoxy resin composition containing 50 to 90 weight% of inorganic fillers with respect to the total amount of.   In the presence of zinc halide, 2-8 equivalents of formaldehyde and hydrogen halide are reacted in the presence of an excess amount of hydrogen halide with respect to 1 mol of biphenyl and biphenyl to carry out halomethylation of biphenyl. , In the ratio (GC area ratio) to the total reaction product in GC-MS, the bishalomethylbiphenyl is 60% or more and less than 80%, and the total of tri (halomethyl) biphenyl and tetra (halomethyl) biphenyl is 15 to A method for producing a phenol resin mixture, comprising: obtaining a reaction product containing 30% and the other by-products, and reacting with phenol without purifying the reaction product.   A method for producing an epoxy resin mixture, comprising reacting a phenol resin mixture obtained by the production method according to claim 10 with 0.8 to 12 equivalents of epihalohydrin with respect to 1 equivalent of a hydroxyl group of the phenol resin mixture.   The epoxy resin composition which contains the phenol resin mixture of Claim 1 or 2 as a hardening | curing agent.