JP2013253153A - Epoxy resin, epoxy resin composition, cured product, and optical member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin that especially excels in cured product characteristics of heat resistance, heat degradation resistance and moisture absorption resistance or the like, in which handleability is excellent, and that is especially useful to a field of an optical member; an epoxy resin composition; and a cured product.SOLUTION: An epoxy resin is obtained by making a phenol compound shown by formula (4) react with epihalohydrin, an epoxy resin composition includes the epoxy resin and a curing agent, and a cured product comprises curing the epoxy resin composition.

Description

  The present invention relates to an epoxy resin, an epoxy resin composition, and a cured product that are excellent in cured product characteristics such as heat resistance, heat degradation resistance, moisture absorption resistance, and the like, and that are excellent in handleability. The present invention also relates to an epoxy resin composition containing the epoxy resin and a curing agent, and a cured product obtained by curing the epoxy resin composition.

  Epoxy resins are excellent in heat resistance, adhesiveness, water resistance, mechanical strength, and electrical properties, so they can be used in various fields such as adhesives, paints, civil engineering and building materials, electrical and electronic materials, and optical components. Used in. In particular, in the field of optical members, light emitting devices such as LEDs and organic EL, solar cells, CCDs, infrared sensors, light receiving devices such as pick-up lenses, optical semiconductor related members such as light distribution boards, optical connectors, lenses, etc. Widely used in applications.

  In particular, in the field of optical members, products using an epoxy resin are exposed to high temperatures, and therefore are required to have excellent heat resistance and heat deterioration resistance. In addition, since the member using the epoxy resin absorbs moisture in the air, there is a problem of product deterioration such as cracking, so that moisture absorption resistance is also required.

  As epoxy resins that have been widely used in the field of optical members, there are bisphenol A type epoxy resins and hydrogenated bisphenol A type epoxy resins with high versatility, all of which have heat resistance, heat deterioration resistance, and moisture absorption resistance. However, many conventional epoxy resins have poor heat resistance, heat deterioration resistance, and moisture absorption resistance.

  On the other hand, Patent Document 1 describes an epoxy resin having high molecular orientation, and a cured product having excellent toughness and moisture resistance. In particular, in the example of Patent Document 1, a bisphenol Z type epoxy resin is manufactured.

JP 2007-254579 A

  According to the study of the present inventors, the bisphenol Z type epoxy resin produced in Example 1 of Patent Document 1 has heat resistance and heat deterioration compared with conventional bisphenol A type epoxy resin and hydrogenated bisphenol A type epoxy. However, it is necessary to further improve the physical properties, although it is excellent in the balance of properties and moisture absorption resistance. Patent Document 1 describes that the bisphenol Z-type epoxy resin of Example 1 is “semi-solid”, and better handling properties are also required.

  In view of the above problems, the present invention is particularly excellent in cured properties such as heat resistance, heat deterioration resistance and moisture absorption, and has good handleability, and is particularly useful in the field of optical members, An object of the present invention is to provide an epoxy resin composition and a cured product.

As a result of intensive studies by the present inventors to solve the above problems, it has been found that an epoxy resin having a specific bisphenol skeleton solves the above problems. That is, the gist of the present invention resides in the following [1] to [8].

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

（上記式（１）において、Ａは上記式（２）で表される化学構造を含み、Ｒは水素原子又は上記式（３）で表される基であり、ｎは繰り返し数の平均値であり０以上１５０以下である。上記式（２）において、Ｒ^１〜Ｒ^４はそれぞれ独立して水素原子又は炭素数１〜２０の炭化水素基である。）

(In the above formula (1), A includes the chemical structure represented by the above formula (2), R is a hydrogen atom or a group represented by the above formula (3), and n is the average number of repetitions. Yes and no greater than 0 and no greater than 150. In the above formula (2), R ^{1 to} R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

[2] An epoxy resin obtained by reacting a phenol compound represented by the following formula (4) with epihalohydrin.

(In the above formula (4), R ^{1 ′ to} R ^{4 ′} may be different from each other, and are a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.)

[3] The epoxy resin according to [1] or [2], wherein the epoxy equivalent is 200 to 30,000 g / equivalent.

[4] An epoxy resin composition comprising the epoxy resin according to any one of [1] to [3] and a curing agent.

[5] The epoxy resin composition according to [4], including 0.01 to 200 parts by weight of the curing agent with respect to 100 parts by weight of the epoxy resin.

[6] The curing agent is at least one selected from the group consisting of an acid anhydride curing agent, a cationic polymerization initiator, an organic phosphorus compound, an amine curing agent, and a tertiary amine, [4] or [4] [5] The epoxy resin composition according to [5].

[7] A cured product obtained by curing the epoxy resin composition according to any one of [4] to [6].

[8] An optical member comprising the epoxy resin composition according to any one of [4] to [6].

  ADVANTAGE OF THE INVENTION According to this invention, the epoxy resin and epoxy resin composition which were excellent in hardened | cured material characteristics, such as heat resistance, heat-resistant deterioration, and moisture absorption resistance, and excellent in the handleability are provided. Moreover, since the epoxy resin composition of the present invention has the above-described features, it can be particularly usefully applied to the field of optical members.

  DESCRIPTION OF EMBODIMENTS Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is an example of the embodiments of the present invention, and the present invention is described below unless the gist of the present invention is exceeded. It is not limited to. In the present specification, when the expression “to” is used, it is used as an expression including numerical values or physical property values before and after the expression.

〔Epoxy resin〕
The epoxy resin of this invention is represented by following formula (1), It is characterized by the above-mentioned. The epoxy resin of the present invention has a feature that it is particularly excellent in heat resistance, heat deterioration resistance and moisture absorption resistance. The reason why the epoxy resin of the present invention has these features is not clear, but it is estimated that the excellent heat resistance and heat deterioration resistance are due to the rigid skeleton of the cyclododecyl group in the formula (2). Hygroscopic resistance is sterically bulky in the cyclododecyl group in the formula (2), so that the total volume occupied by phenol-derived structural parts that are likely to absorb moisture is relative to the entire epoxy resin compared to conventional epoxy resins. This is probably due to the small size.

(In the above formula (1), A includes the chemical structure represented by the above formula (2), R is a hydrogen atom or a group represented by the above formula (3), and n is the average number of repetitions. Yes and no greater than 0 and no greater than 150. In the above formula (2), R ^{1 to} R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

<Chemical structure>
In the formula (1), A includes a chemical structure represented by the formula (2). As described above, the cyclododecyl group in the formula (2) makes the epoxy resin of the present invention excellent in heat resistance, heat deterioration resistance, moisture absorption resistance and the like. In the formula (1), when n = 0, A in the formula (1) is a structure represented by the formula (2).

  A in the formula (1) may contain other than the structural unit represented by the formula (2). However, from the viewpoint of obtaining the effect of the present invention, the structural unit represented by the formula (2) is preferably 30 mol% or more, more preferably 50 mol% or more with respect to the whole A in the formula (1). More preferably, it is 80 mol% or more, and the upper limit is 100 mol%. It is particularly preferable to contain the structural unit represented by the formula (2) at 100 mol%. In addition, the quantity of the structural unit represented by Formula (2) with respect to the whole A shall be determined by the molar ratio of the raw material mentioned later. Moreover, as A in Formula (1), what is illustrated in the manufacturing method mentioned later as an example of chemical structures other than Formula (2) is mentioned.

In said formula (2), R < ¹ > -R < ⁴ > may mutually differ, and is a hydrogen atom or a C1-C20 hydrocarbon group. Here, the “C1-C20 hydrocarbon group” in R ^{1 to} R ⁴ includes any aliphatic hydrocarbon group or aromatic hydrocarbon group having 1 to 20 carbon atoms, and among these, , Methyl group, ethyl group, 1-propyl group, 2-propyl group, 1-butyl group, 2-butyl group, 1-pentyl group, 2-pentyl group, 3-pentyl group, 1-hexyl group, 2-hexyl Preferred examples include C1-C6 aliphatic hydrocarbon groups such as a group, 3-hexyl group, and cyclohexyl group, and C6-C10 aromatic hydrocarbon groups such as phenyl group, benzyl group, and naphthyl group. It is done. Most preferable as R ^{1 to} R ⁴ is a hydrogen atom from the viewpoint of heat resistance, and a methyl group from the viewpoint of heat resistance deterioration and moisture absorption resistance.

In the formula ^(2), the substitution position of R 1 to R ⁴ may be any of the position of b~f in formula (2) ', ^but, R 1 to R ⁴ is from 1 to 20 carbon atoms carbide In the case of a hydrogen group, the substitution position is preferably the position of b, c, e, f, and more preferably the position of b and / or f. Further, in the formula (2), the substitution position of the cyclododecyl group may be any of the positions b to f, but preferably from the viewpoint of efficiently obtaining heat resistance based on the cyclododecyl group. is there.

(In the above formula (2) ′, R ^{1 to} R ⁴ are the same as defined in the above formula (2).)

  In said Formula (1), n is a repeating number and is an average value. The value of n is 0 or more, and is 300 or less from the viewpoint of improving the handleability. The value of n is preferably 0.15 or more, while it is preferably 100 or less, more preferably 80 or less, and even more preferably 50 or less, from the viewpoint of further improving the handleability of the epoxy resin. Yes, particularly preferably 20 or less, and most preferably 5 or less. The number n can be obtained by the method described in the examples below.

<Physical properties / characteristics>
[Epoxy equivalent]
The epoxy resin of the present invention has an epoxy equivalent of preferably 200 g / equivalent or more, more preferably 220 g / equivalent or more, from the viewpoint of obtaining physical properties such as heat resistance, heat deterioration resistance, and hygroscopicity based on the skeleton of formula (2). On the other hand, from the viewpoint of improving the handleability, it is preferably 30,000 g / equivalent or less, more preferably 10,000 g / equivalent or less, still more preferably 6,000 g / equivalent or less, and 1,000 g / equivalent or less. Is particularly preferred. In the present invention, “epoxy equivalent” is defined as “the mass of an epoxy resin containing one equivalent of an epoxy group” and can be measured according to JIS K7236.

[Softening point]
The softening point of the epoxy resin of the present invention is preferably 30 ° C. or higher, and more preferably 40 ° C. or higher. On the other hand, the softening point is preferably 120 ° C., more preferably 110 ° C. or less. When the softening point is equal to or higher than the lower limit, blocking where the epoxy resin is fused hardly occurs, and the handleability at normal temperature (25 ° C.) tends to be good. On the other hand, it is preferable that the softening point is not more than the above upper limit value because the handleability and workability are improved. In the present invention, the softening point of the epoxy resin means a value based on the JIS K-7234 ring and ball method, and that the softening point of the epoxy resin is 30 ° C. or higher is defined as solid at room temperature. To do.

[viscosity]
In the present invention, when expressed by the viscosity of the epoxy resin at 150 ° C. measured with a cone plate type viscometer, the viscosity is preferably higher from the viewpoint of the handleability of the epoxy resin, more specifically, preferably 50 mPa · s. It is above, More preferably, it is 100 mPa * s or more. On the other hand, the upper limit is not particularly limited, but is usually 1,000 mPa · s.
It is as follows.

[Total chlorine content]
The epoxy resin of the present invention preferably has a total chlorine content of 0.2% by mass or less, particularly when used for electric / electronic parts. It is preferable for the total chlorine content to be 0.2% by mass or less because metal corrosion is less likely to occur when used with a metal material such as aluminum. Although there is no restriction | limiting in particular about the minimum of total chlorine content, Usually, it is 0.01 mass% or more. The total chlorine content of the epoxy resin can be determined by titrating with a silver nitrate solution or the like.

<Method for producing epoxy resin>
Although there is no restriction | limiting in particular about the manufacturing method of the epoxy resin of this invention, For example, the manufacturing method by the one-step method demonstrated below, the manufacturing method by a two-step method, the manufacturing method via an allylation reaction, etc. are mentioned. These methods are described in detail below.

[Production method by one-step method]
An epoxy resin according to another embodiment of the present invention is obtained by reacting a phenol compound represented by the following formula (4) with epihalohydrin.

(In the above formula (4), R ^{1 ′ to} R ^{4 ′} may be different from each other, and are a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.)

In the formula (4), R ^{1 ′ to} R ^{4 ′} are R ^{1 to} R ⁴ in the formula (2), respectively.
The same applies to preferred types thereof. Also, R ^{1 ′ to} R ^{4 ′}
The same applies to the replacement position of.

  When the epoxy resin of the present invention is produced by a one-step method, at least a phenol compound represented by the formula (4) and an epihalohydrin are used as raw materials, but a dihydroxy compound other than the phenol compound represented by the formula (4) (present) In the invention, it may be referred to as “other dihydroxy compounds”). However, from the viewpoint of enhancing the effect of the present invention, the proportion of the phenol compound represented by the formula (4) is preferably 30 mol% or more, more preferably 50 mol% or more, and more preferably 50 mol% or more, based on the total dihydroxy compound used as a raw material. Preferably it is 80 mol% or more, and the upper limit is 100 mol%, and 100 mol% is especially preferable. The “dihydroxy compound” in the present invention is a general term for a dihydric phenol compound and a dihydric alcohol.

  Other dihydroxy compounds include bisphenols such as bisphenol A, bisphenol C, bisphenol F, bisphenol S, bisphenol Z, and bisphenol AF; biphenols such as 3,3-5,5-tetraalkylbiphenol and 4,4-biphenol. Ethylene glycol, trimethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,6- Chain aliphatic diols such as hexanediol; cycloaliphatic diols such as cyclohexanediol and cyclodecanediol; polyethylene ether glycol, polyoxytrimethylene ether glycol, polypropylene ether glycol Polyalkylene ether glycols, and the like and the like.

  The dihydroxy compound used as a raw material is usually dissolved in an amount of epihalohydrin corresponding to 0.8 to 20 molar equivalents, preferably 0.9 to 15 molar equivalents, more preferably 1.0 to 10 molar equivalents per equivalent of hydroxyl groups. To make a uniform solution. It is preferable for the amount of epihalohydrin to be not less than the above lower limit value because the high molecular weight reaction can be easily controlled and an appropriate melt viscosity can be obtained. On the other hand, when the amount of epihalohydrin is less than or equal to the above upper limit, production efficiency tends to improve, which is preferable.

  Next, while stirring the solution, usually 0.5 to 2.0 molar equivalents, more preferably 0.7 to 1.8 molar equivalents, and still more preferably 0.9 to 1 molar equivalents per hydroxyl group of the raw material. An amount of alkali metal hydroxide corresponding to 6 molar equivalents is added as a solid or an aqueous solution and reacted. It is preferable for the amount of the alkali metal hydroxide to be not less than the above lower limit because the unreacted hydroxyl group and the generated epoxy resin are difficult to react and the high molecular weight reaction can be easily controlled. Further, it is preferable that the alkali metal hydroxide is not more than the above upper limit because impurities due to side reactions are not easily generated.

This reaction can be carried out under normal pressure or reduced pressure, and the reaction temperature is usually preferably 20 to 150 ° C., more preferably 30 to 120 ° C., and still more preferably 35 in the case of reaction under normal pressure.
In the case of reaction under reduced pressure, it is preferably 20 to 100 ° C, more preferably 30 to 90 ° C, and further preferably 35 to 80 ° C. It is preferable that the reaction temperature is equal to or higher than the above lower limit because the reaction can easily proceed. Further, it is preferable that the reaction temperature is equal to or lower than the above upper limit because side reactions are unlikely to proceed, and chlorine impurities are particularly easily reduced.

  In the reaction, the reaction liquid is azeotroped while maintaining a predetermined temperature as required, the condensed liquid obtained by cooling the vaporized vapor is separated into oil / water, and the oil component excluding moisture is returned to the reaction system. To dehydrate. The addition of alkali metal hydroxide is preferably 0.5 to 8 hours, more preferably 1 to 7 hours, and still more preferably 1 to 6 hours, in order to suppress a rapid reaction, intermittently or continuously. Add it. It is preferable for the addition time to be equal to or more than the above lower limit because the reaction can be prevented from proceeding rapidly and the reaction temperature can be easily controlled. It is preferable for the addition time to be less than or equal to the above upper limit because chlorine impurities are less likely to be generated, and from the viewpoint of economy. The total reaction time is usually 1 to 15 hours.

  After completion of the reaction, the insoluble by-product salt is removed by filtration or removed by washing with water, and then the unreacted epihalohydrin is removed by distillation under reduced pressure to obtain the desired epoxy resin. As epihalohydrin in this reaction, epichlorohydrin or epibromohydrin is usually used. As the alkali metal hydroxide, sodium hydroxide or potassium hydroxide is usually used.

In this reaction, quaternary ammonium salts such as tetramethylammonium chloride and tetraethylammonium bromide; tertiary amines such as benzyldimethylamine and 2,4,6-tris (dimethylaminomethyl) phenol; 2-ethyl Catalysts such as imidazoles such as -4-methylimidazole and 2-phenylimidazole; phosphonium salts such as ethyltriphenylphosphonium iodide; phosphines such as triphenylphosphine may be used.

Furthermore, in this reaction, alcohols such as ethanol and isopropanol; ketones such as acetone and methyl ethyl ketone; ethers such as dioxane and ethylene glycol dimethyl ether; glycol ethers such as methoxypropanol; aprotic such as dimethyl sulfoxide and dimethylformamide An inert organic solvent such as a polar solvent may be used.

  Furthermore, when it is necessary to reduce the total chlorine content of the epoxy resin obtained as described above, a purified epoxy resin having a sufficiently reduced total chlorine content can be obtained by reprocessing. That is, the crude epoxy resin is redissolved in an inert organic solvent such as isopropyl alcohol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, dioxane, methoxypropanol, dimethyl sulfoxide, and the alkali metal hydroxide is added to the solid or aqueous solution. The temperature is preferably 30 to 120 ° C., more preferably 40 to 110 ° C., still more preferably 50 to 100 ° C., preferably 0.1 to 15 hours, more preferably 0.3 to 12 hours, still more preferably 0.00. After re-ringing reaction for 5 to 10 hours, excess alkali metal hydroxide or by-product salt is removed by a method such as washing with water, and further the organic solvent is distilled off under reduced pressure and / or steam distillation to hydrolyze. It is possible to obtain an epoxy resin with a reduced amount of reactive halogen. It is preferable that the reaction temperature is not less than the above lower limit and the reaction time is not less than the above lower limit because the re-ring closure reaction easily proceeds. Moreover, since reaction temperature is below the said upper limit and reaction time is below the said upper limit, since reaction is easy to control, it is preferable.

[Production method by two-stage method]
The epoxy resin of the present invention comprises at least a phenol compound represented by the formula (4) and / or a bifunctional epoxy resin obtained using the phenol compound (for example, an epoxy resin according to another embodiment of the present invention). It can also be obtained as a raw material and reacted by a two-stage method.

  When the epoxy resin of the present invention is produced by the two-stage method, at least the phenol compound represented by the formula (4) and / or the bifunctional epoxy resin obtained using the phenol compound is used as a raw material. Other dihydroxy compounds and / or bifunctional epoxy resins obtained using the other dihydroxy compounds as raw materials may be used in combination. However, from the viewpoint of enhancing the effect of the present invention, the total ratio of the phenol compound represented by the formula (4) and the bifunctional epoxy resin obtained using the phenol compound is the total dihydroxy compound and the total 2 Preferably it is 30 mol% or more with respect to the sum total of a functional epoxy resin, More preferably, it is 50 mol% or more, More preferably, it is 80 mol% or more, and the upper limit is 100 mol%. Particularly preferred is 100 mol%.

  As the other dihydroxy compounds, any of those listed in the item “Production method by one-step method” can be used. The bifunctional epoxy resin obtained using other dihydroxy compounds as raw materials corresponds to a bifunctional epoxy resin obtained by reacting other dihydroxy compounds with epihalohydrin.

The bifunctional epoxy resin used in the production of the epoxy resin of the present invention preferably has a hydrolysis chlorine concentration which is an end group impurity of 200 ppm or less, and an α glycol group concentration of 100 meq / kg or less. Is preferred. The bifunctional epoxy resin has a hydrolysis chlorine concentration of 200 ppm or less, or an α glycol group concentration of 100 meq / kg.
The following is preferable because it is easy to increase the molecular weight.

  In the production of the epoxy resin of the present invention, the amount of the above bifunctional epoxy resin and dihydroxy compound used is such that (epoxy group) :( hydroxyl group) = 1: 0.90 to 1.10. Is preferable. It is preferable for this equivalent ratio to be in the above range because high molecular weight can be easily promoted.

  A catalyst may be used for the synthesis of the epoxy resin of the present invention, and any catalyst may be used as long as it has a catalytic ability to promote a reaction between an epoxy group and a phenolic hydroxyl group, an alcoholic hydroxyl group or a carboxyl group. Something like that. For example, alkali metal compounds, organic phosphorus compounds, tertiary amines, quaternary ammonium salts, cyclic amines, imidazoles and the like can be mentioned.

  Specific examples of the alkali metal compound include alkali metal hydroxides such as sodium hydroxide, lithium hydroxide and potassium hydroxide; alkali metal salts such as sodium carbonate, sodium bicarbonate, sodium chloride, lithium chloride and potassium chloride; sodium Examples include alkali metal alkoxides such as methoxide and sodium ethoxide; alkali metal hydrides such as alkali metal phenoxide, sodium hydride and lithium hydride; and alkali metal salts of organic acids such as sodium acetate and sodium stearate.

  Specific examples of the organic phosphorus compound include tri-n-propylphosphine, tri-n-butylphosphine, triphenylphosphine, tetramethylphosphonium bromide, tetramethylphosphonium iodide, tetramethylphosphonium hydroxide, tetrabutylphosphonium hydroxide, Trimethylcyclohexylphosphonium chloride, trimethylcyclohexylphosphonium bromide, trimethylbenzylphosphonium chloride, trimethylbenzylphosphonium bromide, tetraphenylphosphonium bromide, triphenylmethylphosphonium bromide, triphenylmethylphosphonium iodide, triphenylethylphosphonium chloride, triphenylethylphosphonium bromide, G Phenylethyl phosphonium iodide, triphenyl benzyl phosphonium chloride, triphenyl benzyl phosphonium bromide, and the like.

  Specific examples of the tertiary amine include triethylamine, tri-n-propylamine, tri-n-butylamine, triethanolamine, benzyldimethylamine and the like.

  Specific examples of the quaternary ammonium salt include tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium hydroxide, triethylmethylammonium chloride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, tetrapropylammonium bromide, Tetrapropylammonium hydroxide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium hydroxide, benzyltributylammonium chloride Id, and phenyl trimethylammonium chloride and the like. Among these, tetramethylammonium hydroxide is preferable.

  Specific examples of cyclic amines include 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5,4,0] undecene-7, 1,5-diazabicyclo [4,3,0. ] Nonene-5 etc. are mentioned.

  Specific examples of imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole and the like.

  Among the catalysts mentioned above, quaternary ammonium salts are preferred. Moreover, a catalyst can use only 1 type and can also be used in combination of 2 or more type.

  The amount of catalyst used is usually 0.001 to 1% by weight in the solid content of the reaction. However, when an alkali metal compound is used, the alkali metal component remains in the resulting epoxy resin, and the electronic / electrical component using the same remains. Since there is a possibility of deteriorating the insulating properties, the total atomic content of lithium, sodium and potassium in the epoxy resin is usually 60 ppm or less, preferably 50 ppm or less.

  In addition, when organophosphorus compounds, tertiary amines, quaternary ammonium salts, cyclic amines, imidazoles, etc. are used as catalysts, these remain as catalyst residues in the resulting epoxy resin, and the alkali metal content Since there is a risk of deteriorating the insulating properties of the printed wiring board as well as the residual, the nitrogen content in the epoxy resin is preferably 300 ppm or less, and the phosphorus content in the epoxy resin is preferably 300 ppm or less. is there. More preferably, the content of nitrogen in the epoxy resin is 200 ppm or less, and the content of phosphorus in the epoxy resin is 200 ppm or less.

  The epoxy resin of the present invention may use a reaction solvent in the step of the synthesis reaction at the time of production, and any solvent may be used as long as it dissolves the epoxy resin. Examples include aromatic solvents, ketone solvents, amide solvents, glycol ether solvents, and the like. The solvent may be used alone or in combination of two or more.

  Specific examples of the aromatic solvent include benzene, toluene, xylene and the like. Specific examples of the ketone solvent include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, 2-heptanone, 4-heptanone, 2-octanone, cyclohexanone, acetylacetone, dioxane and the like.

  Specific examples of the amide solvent include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methylpyrrolidone and the like.

  Specific examples of the glycol ether solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol. Examples include mono-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, propylene glycol monomethyl ether acetate and the like.

  The solid concentration in the synthesis reaction during the production of the epoxy resin is preferably 35 to 95% by weight. Further, when a highly viscous product is produced during the reaction, the reaction can be continued by adding an additional solvent. After completion of the reaction, the solvent can be removed or further added as necessary.

In the production of the epoxy resin, the polymerization reaction between the bifunctional epoxy resin and the bisphenol compound is carried out at a reaction temperature at which the used catalyst is not decomposed. If the reaction temperature is too high, the produced epoxy resin may be deteriorated. Conversely, if the temperature is too low, the reaction may not proceed sufficiently. For these reasons, the reaction temperature is preferably 50 to 230 ° C, more preferably 120 to 200 ° C. Moreover, reaction time is 1 to 12 hours normally, Preferably it is 3 to 10 hours. When using a low boiling point solvent such as acetone or methyl ethyl ketone, the reaction temperature can be ensured by carrying out the reaction under high pressure using an autoclave.

[Production method by oxidation of allyl compound]
As one method for producing the epoxy resin of the present invention, an allyl group is introduced into the phenol compound represented by the formula (4) by an allylation reaction to form an allyl compound, and the allyl group is further oxidized. The method of using it as an epoxy resin is mentioned.

  The allyl compound that is a precursor of the epoxy resin can be obtained by reacting the phenol compound represented by the formula (4) with allyl chloride.

  In the allylation reaction, the use ratio of allyl chloride with respect to the phenol compound represented by formula (4) is not particularly limited, but allyl is one mole per hydroxyl group of the phenol compound represented by formula (4). As a chloride, it is 0.8-2 molar equivalent normally, Preferably it is 0.9-1.2 molar equivalent. When the amount of allyl chloride used is not less than the above lower limit value, the raw material tends to be sufficiently reactive, and when it is not more than the above upper limit value, the chlorine content tends to decrease. preferable.

  The temperature of the allylation reaction is not particularly limited, but is usually 40 ° C. or higher, preferably 45 ° C. or higher, and is usually 100 ° C. or lower, preferably 80 ° C. or lower. Further, the pressure of the allylation reaction is not particularly limited and can be performed at normal pressure (atmospheric pressure). However, since allyl chloride has a low boiling point (boiling point 45 ° C.), the reaction may be performed in a closed system. preferable. When the reaction is carried out in a closed system, the internal pressure is usually not lower than normal pressure because it is in a pressurized state, and is usually 1 MPa or less, preferably 0.3 MPa or less.

  The allylation reaction is usually carried out in the absence of a solvent or in the presence of a base. The solvent is not particularly limited, but aprotic polar solvents such as N, N′-dimethylformamide, N-methylpyrrolidone and dimethyl sulfoxide; aprotic nonpolar materials such as acetonitrile, tetrahydrofuran, dioxane and 1,2-dimethoxyethane Organic solvents; alcohols such as methanol, ethanol, 2-propanol and n-butanol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; aromatic hydrocarbons such as benzene, toluene and xylene; can give. These solvents may be used alone or in combination of two or more, and may be used in combination with an inexpensive solvent particularly from the viewpoint of cost.

In addition, when an aprotic polar solvent is used, allylation to the nucleus is reduced, the selectivity of the target allyl compound is improved, and the reaction of impurities to the nucleus is similarly suppressed. This is preferable because a small amount of high-purity allyl compound tends to be obtained. Among the aprotic polar solvents, those having a dielectric constant of 20 or more, more preferably 30 or more are preferable, and those corresponding to these include N, N′-dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide N, N′-dimethylacetamide, N-methylpyrrolidinone, dimethylsulfone, tetramethylurea, hexamethylsulfamide, tetramethylenesulfone, and the like, or a combination thereof. Among these, N, N′-dimethylformamide (dielectric constant 38), N-methylpyrrolidone (dielectric constant 32), dimethyl sulfoxide (dielectric constant 47), and the like, and N, N′-dimethylformamide are particularly preferred. preferable. In view of cost, these solvents can be mixed with an inexpensive polar solvent. For example, N, N′-dimethylformamide can be mixed with acetone (dielectric constant 20).

  The allylation reaction is usually performed in the presence of a base, but the base is not particularly limited, but potassium carbonate, sodium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide, Inorganic bases such as lithium hydroxide, sodium hydride, metallic sodium and metallic potassium; amines such as triethylamine and trimethylamine; and organic bases such as anilines such as pyridine and N, N-dimethylaniline. Depending on the type of solvent, some may be decomposed by a base, and therefore, the combination with the solvent is used. For example, when N, N-dimethylformamide, dimethyl sulfoxide, and acetone are used, potassium carbonate and sodium carbonate are preferable. When the reaction is carried out in a closed system, it is preferable that the reaction does not cause gas generation due to the progress of the reaction.

  A purified allyl compound can be produced by purifying the reaction solution containing the allyl compound obtained through the reaction step by the following method. Examples of the purification method of the allyl compound include crystallization, hanging washing, liquid separation, adsorption, sublimation and the like when the allyl compound is solid, and liquid separation, adsorption and distillation when the allyl compound is liquid.

Purification by liquid separation may involve combining water and an organic solvent that is insoluble or hardly soluble in water, and combining a plurality of organic solvents that are not mixed with each other. Examples of the combination of water and an organic solvent insoluble or hardly soluble in water include a combination of an organic solvent such as ethyl acetate, toluene, diethyl ether, di-isopropyl ether, n-hexane, and water. Examples of combinations of a plurality of organic solvents that are not mixed with each other include, for example, a combination of N, N′-dimethylformamide and at least one of n-heptane, n-hexane, n-pentane, diisopropyl ether, xylene, and dimethyl sulfoxide. n-heptane, n-hexane, n-pentane, diisopropyl ether, diethyl ether, a combination with at least one of xylene, acetonitrile and n-heptane, n-hexane, n-pentane, cyclohexane, cyclopentane There is a combination with at least one of them, and a combination with at least one of methanol and n-heptane, n-hexane and n-pentane.

For purification by crystallization, after completion of the allylation reaction, the inorganic salt in the system is removed by a method such as washing with water, filtration, etc., and then the solvent is distilled off under reduced pressure, or cooled and crystallized without distilling off. A method of precipitating by adding a solvent having a low solubility of the compound, so-called poor solvent, a method of precipitating by combining a solvent having a high solubility of the compound, a so-called easy solvent and a poor solvent, without removing the inorganic salt after completion of the reaction. Any method of adding water to cause crystallization may be used. The solvent may be any organic solvent, water or a mixture thereof, a combination of organic solvents, and the like, and an appropriate one is selected depending on the solubility of the compound. Examples of the organic solvent include esters such as ethyl acetate, aliphatic hydrocarbons such as heptane, hexane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, acetonitrile, tetrahydrofuran, dioxane, 1,2-dimethoxyethane and the like. Aprotic solvents such as methanol, ethanol, alcohols such as 2-propanol and n-butanol, ketones such as acetone and methyl ethyl ketone, aprotic polarities such as N, N-dimethylformamide, N-methylpyrrolidone and dimethyl sulfoxide A solvent is mentioned. In addition, when crystallization is carried out by adding water or an organic solvent, crystallization may be carried out while distilling off unreacted allyl chlorides and by-product low-boiling compounds under reduced pressure.

For purification by hanging washing, a solvent having a low compound solubility, a so-called poor solvent is used. Although a preferable poor solvent changes with compounds, highly polar things, such as alcohol, such as methanol, and low polarity aliphatic hydrocarbons, such as heptane, hexane, and a cyclohexane, are raised conversely. Examples of the water-soluble solvent include tetrahydrofuran, 1,3-dioxolane, N, N-dimethylformamide, dimethyl sulfoxide and the like, and these can be used by mixing with water. When the amount of the solvent is too small, the purification effect is not sufficient, and when it is too large, the recovery rate is lowered. After completion of the hanging washing, the target product can be obtained by collecting the solid by filtration and drying.

  Purification by adsorption includes activated carbon, activated clay, molecular sieves, alumina, zeolite, ion exchange resin and the like as chlorine-containing impurities and adsorbents.

  Among these purification methods, from the viewpoint of the operation method, the liquid separation method and the adsorption method are preferable regardless of the properties of the allyl compound. When the allyl compound is a solid, a crystallization method is effective. The purified allyl compound thus obtained is generally more stable to acids, bases, and heat than an epoxy resin, so that the purification treatment is easy and the polarity tends to be lower than that of an epoxy resin. It has high solubility in the solvent, and separation, extraction, adsorption, and other treatments are easy in the purification process described later.

(Oxidation reaction)
The epoxy resin of the present invention can be obtained by oxidizing the allyl compound obtained by the above-described process using an oxidizing agent.

  As a method for epoxidizing an allyl group by an oxidation reaction, it is preferable to use a non-chlorine (not containing chlorine) oxidizing agent, and a method using an organic peracid and a method of reacting hydrogen peroxide in the presence of a catalyst. Can be mentioned. Examples of the organic peracid include peracetic acid, perbenzoic acid, and tertiary butyl hydroperoxide (TBHP). Among them, peracetic acid that can be easily prepared and worked up is preferable. When using an organic peracid, the acidity in the system may be adjusted by adding a base such as sodium acetate or sodium hydroxide into the system.

  Hydrogen peroxide acts as an oxidizing agent that oxidizes the catalyst in the oxidation reaction (hereinafter, the catalyst and hydrogen peroxide may be collectively referred to as an oxidizing agent composition). Hydrogen peroxide is usually used as a hydrogen peroxide solution, and a commercially available hydrogen peroxide solution can be used as it is or diluted with water. The concentration of the hydrogen peroxide solution is not particularly limited, but is usually 1% by weight or more, preferably 20% by weight or more, and usually 60% by weight or less. More preferably, it is preferably 35% by weight or more and 45% by weight or less in consideration of availability, safety problems, pot efficiency, and the like.

  The amount of hydrogen peroxide used is not particularly limited, but usually 0.5 times mole or more, preferably 0.8 times mole or more, per mole of double bond in the allyl compound used as a raw material. Usually, 10 times mol or less, preferably 3 times mol or less is used.

Catalyst As a catalyst for the oxidation reaction, catalytic metal, catalytic ammonium salt, catalytic phosphoric acid (herein, “catalytic phosphoric acid” is a general term for phosphoric acid and / or a phosphoric acid compound used as a catalyst) and the like. It is done.

  Examples of the catalyst metal include tungstic acid or a tungstic acid salt (hereinafter referred to as tungstic acid), molybdenum or a molybdic acid salt (hereinafter referred to as molybdic acid), or a mixture thereof. Of these, tungstic acids are preferred because of their price and availability.

Specific examples of the tungstic acids include tungstic acid; tungstates such as sodium tungstate, potassium tungstate, and ammonium tungstate; hydrates of the tungstates; 12-tungstophosphoric acid, and 18-tungsten. Phosphotungstic acid such as strinic acid; 12-tungstosilicic acid, 12-tungstoboric acid, metallic tungsten and the like can be mentioned, and tungstic acid, tungstate and 12-tungstophosphoric acid are preferable.

  Examples of the molybdic acids include molybdic acid; molybdates such as sodium molybdate, potassium molybdate, and ammonium molybdate; and hydrates of the molybdates. Among these, tungstic acid or sodium tungstate and its hydrate are preferable in terms of availability.

  The above catalyst metals can be used alone or in combination of two or more. The amount of catalytic metal used in the oxidation reaction can be appropriately adjusted depending on the properties of the substrate used and the like, and is not particularly limited. However, tungsten is used with respect to 1 mol of the double bond contained in the allyl compound used as a raw material. It is usually 0.001 mol or more, preferably 0.005 mol or more, usually 1.0 mol or less, preferably 0.10 mol or less in terms of atoms.

  Examples of the catalyst ammonium salt include tetrahexylammonium hydrogen sulfate, tetraoctylammonium hydrogensulfate, methyltrioctylammonium hydrogensulfate, tetrabutylammonium hydrogensulfate, ethyltrioctylammonium hydrogensulfate, and cetylpyridinium hydrogensulfate. Tetrahexylammonium hydrogen sulfate, tetraoctylammonium hydrogensulfate, methyltrioctylammonium hydrogensulfate and the like are preferable. These quaternary ammonium hydrogen sulfates may be used alone or in combination of two or more. The amount used is usually selected from the range of 0.0001 to 10 mol%, preferably 0.01 to 5 mol%, relative to 1 mol of the double bond contained in the allyl compound.

  Examples of the catalytic phosphoric acid include phosphoric acid, polyphosphoric acid, pyrophosphoric acid, sodium phosphate, potassium phosphate, ammonium phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate, ammonium hydrogen phosphate, phosphate ester and the like. It is done. Of these, phosphoric acid is preferred. Further, the amount of phosphoric acid used is not particularly limited, but as an equivalent of phosphorus contained in the phosphoric acid, usually 0.1 times mol or more with respect to one metal atom in the catalyst metal component to be used, The amount is preferably 0.2 times mol or more, usually 2.0 times mol or less, preferably 1.0 times mol or less.

-Solvent The oxidation reaction can also be carried out in a solvent. The solvent to be used is not particularly limited as long as it does not participate in the reaction, but aromatic hydrocarbons such as benzene, toluene and xylene; aliphatic hydrocarbons such as hexane, heptane and dodecane; methanol and ethanol , Alcohols such as isopropanol, butanol, hexanol and cyclohexanol; halogen solvents such as chloroform, dichloromethane and dichloroethane; ethers such as tetrahydrofuran and dioxane; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and anone; acetonitrile Nitriles such as butyronitrile; ester compounds such as ethyl acetate, butyl acetate and methyl formate; amides such as N, N′-dimethylformamide and N, N′-dimethylacetamide, N, N′-dimethylimidazo Examples include ureas such as lydinone; water and mixtures of these solvents, and water, aromatic hydrocarbons, aliphatic hydrocarbons, and mixtures of these solvents are preferred. More preferably, water and toluene are mentioned.

  The use mode of the solvent is not particularly limited, but the allyl compound used in the reaction may be dissolved or suspended, but is usually dissolved in the solvent under the reaction temperature conditions. Is preferred. The amount of the solvent used depends on the solubility of the compound, but the reaction rate often decreases as the amount of the solvent increases. Therefore, it is usually 0.1 times the amount of the allyl compound, preferably 0.5 times the amount, Usually it is 10 times or less, preferably 3 times or less.

・ Physical properties of oxidizing agent composition In the oxidation reaction, the usage amounts of catalytic metal, catalytic ammonium salt and catalytic phosphoric acid are as described above, but the ratio of the usage amount of catalytic metal, catalytic ammonium salt and catalytic phosphoric acid is The pH of the aqueous layer of the reaction solution is usually 2 or more, preferably 3 or more, usually 6 or less, preferably 5 or less. It is preferable for it to be at least the above lower limit value because the ring-opening reaction of the epoxy group is difficult to proceed. Moreover, since it exists in the tendency for reaction rate to become suitable as it is below the said upper limit, it is preferable. Acids such as phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, and perchloric acid as required; inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate; ammonia, methylamine The pH can be adjusted by adding an organic base such as ethylamine.

  A buffer solution can also be used in the oxidation reaction. As the type of the buffer, any buffer that matches the target pH can be used as long as it does not inhibit the reaction. In this reaction, a phosphate aqueous solution is preferably used. In some cases, the above tungstic acids may be combined to form a buffer solution.

-Reaction operation The reaction operation method in the production method of the oxidation reaction is not particularly limited, but hydrogen peroxide, a catalyst, etc. are added to the allyl compound, and an organic solvent and a buffer solution are added if necessary. Add it. The order of addition and mixing of each component is not limited as long as the reaction is not hindered. However, since there are many cases where heat is generated during the oxidation reaction and decomposition of hydrogen peroxide, hydrogen peroxide is added after each component is added. A method of gradually adding or adding a hydrogen peroxide in an amount necessary for oxidizing a tungsten compound and / or a molybdenum compound in advance to form a tungsten peroxide and then gradually adding the remaining hydrogen peroxide. Is preferred. As a method for adding hydrogen peroxide, it may be added in divided portions or may be added gradually and continuously.

-Reaction conditions Although the reaction temperature in the manufacturing method of an oxidation reaction is not specifically limited unless reaction is inhibited, Usually, 10 degreeC or more, Preferably it is 35 degreeC or more, Usually, 90 degrees C or less, Preferably it is 75 degrees C or less. It is preferable for it to be higher than the lower limit value because the reaction rate tends to be faster, while it is preferable for it to be lower than the upper limit value from the viewpoint of safety.

  The reaction time can be appropriately selected depending on the reaction temperature, the amount of catalyst, the type of raw material, etc., and is not particularly limited, but is usually 1 hour or longer, preferably 3 hours or longer, more preferably 4 hours or longer, usually 48 hours. Hereinafter, it is preferably 36 hours or less, more preferably 24 hours or less. In addition, it is preferable to perform an oxidation reaction under a normal pressure and nitrogen stream from a safety viewpoint.

(Purification)
The epoxy resin obtained by the above method may be further purified as necessary. A specific purification method is not particularly limited, and a known method can be appropriately used. When the epoxy resin is solid or semi-solid, crystallization, hanging washing, liquid separation, adsorption, sublimation and the like can be mentioned. When the epoxy resin is liquid, liquid separation, adsorption and distillation can be mentioned.

Purification by liquid separation may involve combining water and an organic solvent that is insoluble or hardly soluble in water, and combining a plurality of organic solvents that are not mixed with each other. Examples of the combination of water and an organic solvent insoluble or hardly soluble in water include a combination of an organic solvent such as ethyl acetate, toluene, diethyl ether, di-isopropyl ether, n-hexane, and water. Examples of combinations of a plurality of organic solvents that do not mix with each other include N, N′-dimethylformamide and n
A combination of at least one of heptane, n-hexane, n-pentane, diisopropyl ether and xylene, at least of dimethyl sulfoxide and n-heptane, n-hexane, n-pentane, diisopropyl ether, diethyl ether, xylene Combination with one of acetonitrile and n-heptane, n-hexane, n-pentane, cyclohexane, combination with at least one of cyclopentane, methanol and n-heptane, n-hexane, n-pentane There is a combination with at least one.

  For purification by crystallization, the solvent is distilled off under reduced pressure, or it is cooled and crystallized without evaporation, the solvent having low compound solubility, the so-called poor solvent is added, and the compound has high solubility. Any of a method of precipitating by combining a solvent, a so-called easy solvent and a poor solvent, a method of crystallizing by adding water after completion of the reaction, and the like may be used.

The solvent used for crystallization may be any organic solvent, water, a mixture thereof, a combination of organic solvents, or the like, and an appropriate solvent may be selected depending on the solubility of the compound. Examples of organic solvents include esters such as ethyl acetate; aliphatic hydrocarbons such as heptane, hexane, and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; acetonitrile, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, and the like. Aprotic solvents of: alcohols such as methanol, ethanol, 2-propanol, n-butanol; acetone,
Ketones such as methyl ethyl ketone; and aprotic polar solvents such as N, N-dimethylformamide, N-methylpyrrolidone and dimethyl sulfoxide.

  For purification by hanging washing, a solvent having a low compound solubility, that is, a so-called poor solvent is usually used. Although a preferable poor solvent changes with compounds, highly polar things, such as alcohols, such as methanol, and low polarity aliphatic hydrocarbons, such as a pentane, hexane, and a cyclohexane, are raised conversely. Examples of the water-soluble solvent include tetrahydrofuran, 1,3-dioxolane, N, N-dimethylformamide, dimethyl sulfoxide and the like, and these can be used by mixing with water. When the amount of the solvent is too small, the purification effect is not sufficient, and when it is too large, the recovery rate is lowered. After the hanging washing is finished, the solid can be recovered by filtration and further dried to obtain the target product.

  Purification by adsorption includes activated carbon, activated clay, molecular sieves, alumina, zeolite, ion exchange resin and the like as chlorine-containing impurities and adsorbents.

  Among the above-described purification methods, the liquid separation method and the adsorption method are preferable regardless of the properties of the epoxy resin from the viewpoint of the simplicity of the operation method. In particular, the crystallization method is effective when the epoxy resin to be purified is solid.

[Epoxy resin composition]
The epoxy resin composition of the present invention contains at least the above-described epoxy resin of the present invention and a curing agent. In addition, other epoxy resins, inorganic fillers, coupling agents, and the like can be appropriately blended in the epoxy resin composition of the present invention as necessary. The epoxy resin composition of the present invention is excellent in heat resistance, heat deterioration resistance, moisture absorption resistance and the like, and provides a cured product that sufficiently satisfies various physical properties required for various applications.

<Curing agent>
In this invention, a hardening | curing agent shows the substance which contributes to the crosslinking reaction and / or chain length extension reaction between the epoxy groups of an epoxy resin. In the present invention, even if what is usually called a “curing accelerator” is a substance that contributes to a crosslinking reaction and / or chain extension reaction between epoxy groups of an epoxy resin, it is regarded as a curing agent. To do.

The content of the curing agent in the epoxy resin composition of the present invention is preferably 0.01 to 200 parts by weight with respect to 100 parts by weight of the epoxy resin of the present invention. Further, it is more preferably 150 parts by weight or less, still more preferably 100 parts by weight or less, and particularly preferably 80 parts by weight or less. On the other hand, it is more preferably 0.05 parts by weight or more.

  In the epoxy resin composition of the present invention, when other epoxy resins described later are included, the content of the curing agent is preferably 0.01 to 200 weights with respect to 100 parts by weight of the total epoxy resin component as a solid content. Part. Further, it is more preferably 150 parts by weight or less, still more preferably 100 parts by weight or less, particularly preferably 80 parts by weight or less, and more preferably 0.05 parts by weight or more. In the present invention, the “solid content” means a component excluding the solvent, and includes not only a solid epoxy resin but also a semi-solid or viscous liquid material. The “total epoxy resin component” means the total of the epoxy resin of the present invention and other epoxy resins described later.

  There is no restriction | limiting in particular as a hardening | curing agent used for the epoxy resin composition of this invention, What is generally known as an epoxy resin hardening | curing agent can be used. Preferable examples include acid anhydride curing agents, cationic polymerization initiators, organic phosphorus compounds, amine curing agents, tertiary amines, and the like. Examples of acid anhydride curing agents, cationic polymerization initiators, organophosphorus compounds and other usable curing agents are given below.

[Acid anhydride curing agent]
The epoxy resin composition of the present invention preferably uses an acid anhydride curing agent from the viewpoint of heat resistance. Examples of the acid anhydride curing agent include acid anhydrides and modified acid anhydrides.

  Examples of acid anhydrides include phthalic acid anhydride, trimellitic acid anhydride, pyromellitic acid anhydride, benzophenone tetracarboxylic acid anhydride, dodecenyl succinic acid anhydride, polyadipic acid anhydride, polyazelinic acid anhydride, polysebacic acid Anhydride, poly (ethyloctadecanedioic acid) anhydride, poly (phenylhexadecanedioic acid) anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride , Methyl hymic acid anhydride, tetrahydrophthalic acid anhydride, trialkyltetrahydrophthalic acid anhydride, methylcyclohexene dicarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bis trimellitate dianhydride, het acid anhydride , Najit Acid anhydride, methyl nadic acid anhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride, 3,4-dicarboxy- Examples include 1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, and the like.

  Examples of modified acid anhydrides include those obtained by modifying the above acid anhydride with glycol. Examples of glycols that can be used for modification include alkylene glycols such as ethylene glycol, propylene glycol, and neopentyl glycol; polyether glycols such as polyethylene glycol, polypropylene glycol, and potassium tetramethylene ether glycol. Is mentioned. Further, a copolymer polyether recall of two or more kinds of these and / or polyether glycol can also be used.

  In the modified product of acid anhydride, it is preferable to modify with 0.4 mol or less of glycol with respect to 1 mol of acid anhydride. When the modification amount is not more than the above upper limit, the viscosity of the epoxy resin composition does not become too high, the workability tends to be good, and the rate of the curing reaction with the epoxy resin also tends to be good. .

  The acid anhydride curing agents listed above may be used alone or in combination of two or more in any combination and blending amount. When an acid anhydride curing agent is used, it is preferably used so that the equivalent ratio of the functional group in the curing agent to the epoxy group in the epoxy resin is in the range of 0.8 to 1.5. Within this range, unreacted epoxy groups and functional groups of the curing agent are unlikely to remain, which is preferable.

[Cationic polymerization initiator]
The epoxy resin composition of the present invention preferably uses a cationic polymerization initiator from the viewpoint of heat resistance. Examples of the acid anhydride curing agent include acid anhydrides and modified acid anhydrides. Examples of the cationic polymerization initiator include a thermal cationic polymerization initiator that generates a cationic species and / or a Lewis acid by heat, a photocationic polymerization initiator that generates a cationic species and / or a Lewis acid by light, and the like. Note that there is no clear division between the thermal cationic polymerization initiator and the photopolymerization initiator, and some of them act as curing agents for both heat and light.

  Examples of the thermal cationic polymerization initiator include onium salt cationic polymerization initiators such as sulfonium salts, ammonium salts, pyridinium salts phosphonium salts, iodonium salts; combinations of aluminum complexes and silanol compounds, combinations of aluminum complexes and bisphenol S And aluminum complex composite cationic polymerization initiators. Examples of the photocationic polymerization initiator include aromatic diazonium salts, aromatic sulfonium salts, aromatic iodonium salts, metallocene compounds, and the like.

  The cationic polymerization initiator can be obtained as a commercial product. For example, 3M FC-520, Union Carbide UVR-6990, UVR-6974, General Electric UVE-1014, UVE-1016, Degussa KI-85 Asahi Denka SP-15, SP- 170, Sanshin Kagaku Kogyo Co., Ltd. SI-60L, SI-80L, SI-100L, etc. are mentioned.

  Among the cationic polymerization initiators mentioned above, onium salts are preferable from the viewpoint of handleability. Furthermore, among the onium salts, diazonium salts, iodonium salts, sulfonium salts, and phosphonium salts are particularly preferable.

  The cationic polymerization initiator may be used alone or in combination of two or more in any combination and blending ratio. Moreover, it is preferable to use a cationic polymerization initiator by 0.01-15 mass parts with respect to 100 mass parts of epoxy resins of this invention, and it is more preferable to use it by 0.05-5 weight part. It is preferable that the amount of the cationic polymerization initiator used is in the above range because the heat resistance of the cured epoxy resin tends to be good.

[Organic phosphorus compounds]
In the epoxy resin composition of the present invention, it is preferable to use an organic phosphorus compound because the curing reaction is accelerated. Organic phosphorus compounds include tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine and other organic phosphines, methyltributylphosphonium dimethylphosphate, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenyl Examples thereof include phosphonium salts such as borate and tetrabutylphosphonium / tetrabutylborate. In addition, since an organic phosphorus compound has catalytic ability, it can generally be classified as a curing accelerator described later, but in the present invention, it is classified as a curing agent.

The organophosphorus compounds mentioned above may be used alone or in combination of two or more in any combination and blending ratio. The organophosphorus compound is preferably used in an amount of 0.1 to 50 parts by weight, based on a total of 100 parts by weight of the epoxy resin of the present invention and the organophosphorus compound in the epoxy resin composition, and 0.5 to 30 parts by weight. It is more preferable to use in.

[Amine curing agent]
Examples of amine curing agents (excluding tertiary amines) include aliphatic amines, polyether amines, alicyclic amines, aromatic amines and the like. Aliphatic amines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis ( Hexamethylene) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethylethylenediamine, tetra (hydroxyethyl) ethylenediamine and the like are exemplified. Examples of polyether amines include triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis (propylamine), polyoxypropylene diamine, polyoxypropylene triamines, and the like. Cycloaliphatic amines include isophorone diamine, metacene diamine, N-aminoethylpiperazine, bis (4-amino-3-methyldicyclohexyl) methane, bis (aminomethyl) cyclohexane, 3,9-bis (3-amino). Propyl) -2,4,8,10-tetraoxaspiro (5,5) undecane, norbornenediamine and the like. Aromatic amines include tetrachloro-p-xylenediamine, m-xylenediamine, p-xylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2,4 -Toluenediamine, 2,4-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diamino-1,2-diphenylethane, 2,4-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-dimethylaminomethyl) phenol, triethanolamine, methylbenzylamine, α- (m-aminophenyl) ethylamine, α- (p-aminophenyl) ethylamine Diaminodiethyldi Examples thereof include methyldiphenylmethane and α, α′-bis (4-aminophenyl) -p-diisopropylbenzene.

  The amine curing agents mentioned above may be used alone or in combination of two or more in any combination and mixing ratio. Moreover, it is preferable to use an amine hardening | curing agent so that it may become the range of 0.8-1.5 by the equivalent ratio of the functional group in a hardening | curing agent with respect to the epoxy group in an epoxy resin. Within this range, unreacted epoxy groups and functional groups of the curing agent are unlikely to remain, which is preferable.

[Tertiary amine]
Examples of the tertiary amine include 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol. .

  The tertiary amines mentioned above may be used alone or in combination of two or more in any combination and blending ratio. Moreover, it is preferable to use a tertiary amine so that it may become the range of 0.8-1.5 in the equivalent ratio of the functional group in the hardening | curing agent with respect to the epoxy group in an epoxy resin. Within this range, unreacted epoxy groups and functional groups of the curing agent are unlikely to remain, which is preferable.

[Other curing agents]
As a curing agent that can be used in the epoxy resin composition of the present invention, an acid anhydride curing agent, a cationic polymerization initiator, an organic phosphorus compound, an amine curing agent (excluding a tertiary amine), and a third. Examples other than the primary amine include, for example, amide type curing agents, phenol type curing agents, imidazoles, tetraphenyl boron salts, organic acid dihydrazides, boron halide amine complexes, polymercaptan type curing agents, isocyanate type curing agents, and blocks. Isocyanate-based curing agents and the like. The other curing agents mentioned above may be used alone or in combination of two or more.

<Other epoxy resins>
The epoxy resin composition of the present invention can contain other epoxy resins in addition to the epoxy resin of the present invention. By using other epoxy resins, the insufficient physical properties can be compensated or various physical properties can be improved.

  The other epoxy resin preferably has two or more epoxy groups in the molecule, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol Z type epoxy resin. Bisphenol AF type epoxy resin, bisphenol AD type epoxy resin, tetramethylbisphenol A type epoxy resin, tetramethylbisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, hydrogenated bisphenol S type Epoxy resin, hydrogenated bisphenol Z type epoxy resin, hydrogenated bisphenol AF type epoxy resin, hydrogenated bisphenol AD type epoxy resin, biphenol type epoxy resin, tetramethylbiphenol type epoxy resin Naphthalene type epoxy resin, diglycidyl ether of bisphenol A-alkylene oxide adduct, diglycidyl ether of alkylene oxide adduct of bisphenol F, thiodiphenol type epoxy resin, dihydroxydiphenyl ether type epoxy resin, terpene diphenol type epoxy resin, hydroquinone Type epoxy resin, methyl hydroquinone type epoxy resin, dibutyl hydroquinone type epoxy resin, resorcin type epoxy resin, methyl resorcin type epoxy resin, dihydroxy naphthalene type epoxy resin, etc .; phenol novolac type epoxy resin, cresol novolac type epoxy Resin, bisphenol A novolac type epoxy resin, dicyclopentadienephenol type epoxy resin, tellurium Phenolic epoxy resin, phenol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, naphthol novolak type epoxy resin, polyhydric phenol resin obtained by condensation reaction with various aldehydes such as hydroxybenzaldehyde, crotonaldehyde, glyoxal, petroleum Resin, triglycidyl isocyanurate produced from various phenolic compounds such as modified phenolic resins obtained by polycondensation of heavy oils or pitches, formaldehyde polymers and phenols in the presence of an acid catalyst, and epihalohydrin And various epoxy resins such as polyfunctional epoxy resins (in the present invention, “polyfunctional epoxy resin” means a trifunctional or higher functional epoxy resin).

  In the epoxy resin composition of the present invention, when the epoxy resin of the present invention and another epoxy resin are used, the amount of the other epoxy resin in the total epoxy resin component as a solid content is preferably 1% by weight or more. Yes, more preferably 5% by weight or more, while preferably 99% by weight or less, more preferably 95% by weight or less. When the ratio of the other epoxy resin is not less than the above lower limit value, the effect of improving the physical properties by blending the other epoxy resin can be sufficiently obtained, and in particular, it is more excellent in heat resistance than the epoxy resin itself of the present invention. Material can be obtained. On the other hand, when the ratio of the other epoxy resin is not more than the above upper limit value, the effect of the epoxy resin of the present invention is sufficiently exhibited, and low hygroscopicity can be obtained.

<Solvent>
In the epoxy resin composition of the present invention, a solvent may be blended and diluted in order to appropriately adjust the viscosity of the epoxy resin composition during handling during the formation of the coating film. In the epoxy resin composition of the present invention, the solvent is used in order to ensure the handleability and workability in the molding of the epoxy resin composition, and the amount used is not particularly limited. In the present invention, the term “solvent” and the above-mentioned term “solvent” are distinguished from each other depending on the form of use, but the same or different ones may be used independently.

  Examples of the solvent that can be contained in the epoxy resin composition of the present invention include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone, esters such as ethyl acetate, ethers such as ethylene glycol monomethyl ether, N, Examples thereof include amides such as N-dimethylformamide and N, N-dimethylacetamide, alcohols such as methanol and ethanol, alkanes such as hexane and cyclohexane, and aromatics such as toluene and xylene. The solvent mentioned above may be used only by 1 type, and may mix and use 2 or more types by arbitrary combinations and a ratio.

<Other ingredients>
In the epoxy resin composition containing the epoxy resin of the present invention, components other than those listed above (sometimes referred to as “other components” in the present invention) for the purpose of further improving the functionality. May be included. Such other components include curing accelerators (except for those contained in “curing agents”), UV inhibitors for improving storage stability, plasticizers, and removal of solder oxide films. Examples thereof include a flux, an inorganic filler, a coupling agent, an antioxidant, a flame retardant, a colorant, a pigment, a dispersant, an emulsifier, a low elastic agent, a diluent, an antifoaming agent, and an ion trapping agent.

[Cured product]
A cured product can be obtained by curing the epoxy resin composition of the present invention (hereinafter referred to as “cured product of the present invention”). The hardened | cured material of this invention is excellent in hardened | cured material characteristics, such as heat resistance, heat-resistant deterioration, and moisture absorption resistance.

  The method for obtaining the cured product of the present invention is not particularly limited. Usually, after mixing an epoxy resin and a curing agent and other components blended as necessary, the curing reaction is allowed to proceed by light and / or heat. Can be obtained. More specifically, an epoxy resin and a curing agent, a method of uniformly mixing while heating and melting at 40 to 120 ° C., and other components to be blended as needed, an epoxy resin while precuring the curing agent The composition is prepared, and the resulting epoxy resin composition is usually molded and cured at 100 to 200 ° C. for 0.1 to 20 minutes, and in order to further improve the curing performance, usually at a temperature of 70 to 200 ° C. And a method of performing post-curing in the range of 0.1 to 10 hours.

  A cured product obtained by curing the epoxy resin of the present invention with a curing agent is excellent in heat resistance, heat deterioration resistance, moisture absorption resistance, and the like, and exhibits excellent cured product characteristics. The term “curing” as used herein generally means that the epoxy resin composition is intentionally cured by heat and / or light after mixing an epoxy resin and a curing agent and other components blended as necessary. This means that the degree of curing may be controlled according to desired physical properties and applications. The degree of progression may be completely cured or semi-cured, and is not particularly limited. However, the reaction rate of the curing reaction between the epoxy group and the curing agent is usually 5 to 95%.

  The curing method of the epoxy resin composition when the epoxy resin composition of the present invention is cured or semi-cured to obtain a cured product or semi-cured product is not particularly limited, and also depends on the compounding component and blending amount in the epoxy resin composition. Although it is different, usually, a method of uniformly mixing while heating and melting at 40 to 120 ° C., adjusting an epoxy resin composition while performing a preliminary reaction of a curing agent, and the obtained epoxy resin composition is usually 100 to 200 ° C. For example, a method of post-curing at a temperature of 70 to 200 [deg.] C. for 0.1 to 10 hours may be used in order to form and cure at 0.1 to 20 minutes, and to further improve the curing performance.

When producing the resin semi-cured product, the curing reaction of the epoxy resin composition is advanced to such an extent that the shape can be maintained by heating or the like. When the epoxy resin composition contains a solvent, most of the solvent is removed by techniques such as heating, decompression, and air drying, but a solvent of 5% by mass or less may remain in the resin semi-cured product. .

[Use]
The epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin are excellent in cured product properties such as heat resistance, heat deterioration resistance, and moisture absorption resistance, and the epoxy resin of the present invention is also excellent in handleability. For this reason, light emitting devices such as LEDs and organic ELs; light receiving devices such as solar cells, CCDs, infrared sensors, and pickup lenses; particularly in applications of various optical members such as optical power distribution plates, optical connectors, and optical semiconductor-related members such as lenses. Although useful, the use is not limited to these, and can be suitably applied to various uses such as adhesives, paints, materials for civil engineering and construction, and insulating materials for electric / electronic parts.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely using an Example, this invention is not limited to description of a following example, unless it deviates from the summary. In addition, the value of various manufacturing conditions and evaluation results in the following examples has a meaning as a preferable value of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-described upper limit or lower limit value. A range defined by a combination of values of the following examples or values of the examples may be used.

[Methods for measuring physical properties and evaluating performance of epoxy resins]
The epoxy resin, the epoxy resin composition, and the method for measuring the physical properties of the cured product and the method for evaluating the performance obtained in the following examples are as follows.

<N number>
Using “HLC-8320GPC EcoSEC (registered trademark)” manufactured by Tosoh Corporation, measurement was performed under the following conditions. N number was computed from ratio of the obtained area%.
Column: “TSKGEL SuperHM-H + H5000 + H4000 + H3000 + H2000” manufactured by Tosoh Corporation
Eluent: Tetrahydrofuran Flow rate: 0.5 ml / min
Detection: UV (wavelength 254 nm)
Temperature: 40 ° C
Sample concentration: 0.1% by weight
Injection volume: 10 μl

<Epoxy equivalent>
It measured according to JIS K-7236.

<Softening point>
Measured by JIS K-7234 ring and ball method.

<Viscosity>
The viscosity of the epoxy resin at 150 ° C. was measured using a cone plate type viscometer.

[Methods for measuring physical properties and evaluating performance of cured products]
<Heat resistance>
The glass transition temperature Tg was measured by the TMA method (temperature rising at 5 ° C./min). It shows that it is excellent in heat resistance, so that the value of this Tg is high.

<Heat resistance degradation>
Two sheets were prepared by attaching a polyethylene terephthalate film to one side of a soft glass plate having a length of 20 cm, a width of 20 cm, and a thickness of 8 mm. One glass plate to which the film was attached was placed so that the film was on top, and a silicone tube having an outer diameter of 4 mm and an inner diameter of 2 mm was placed in a U shape thereon. Place a metal plate with a thickness of 2 mm at the four corners of the glass plate, and stack another glass plate with a pre-made film on it so that the film is on the bottom. did. The epoxy resin composition was poured therein and cured in an oven at 100 ° C. for 3 hours and then at 140 ° C. for 3 hours to obtain a cured epoxy resin having a thickness of 2 mm. The cured product created by this method was cut into a 6 cm square on a side with a diamond cutter to obtain a test piece.

  After leaving the test piece in an oven (in an Air atmosphere) at 150 ° C. for 100 hours, taking it out from the oven, cooling at room temperature, using a color difference meter (Nippon Denshoku Industries ZE2000) using a color difference meter, The color difference YI value (Yellow Index) before and after the heat deterioration test was measured. It shows that it is excellent in heat-resistant deterioration, so that this value is small.

<Hygroscopic resistance>
Using a test piece preparation jig in which a stainless steel plate having a thickness of 3 mm was punched into a circle having a diameter of 50 mm, a polyethylene terephthalate film was attached to one side of the jig (steel plate) and placed in an oven. The epoxy resin composition was poured therein and cured in an oven at 100 ° C. for 3 hours and then at 140 ° C. for 3 hours to obtain a disk-shaped cured product having a diameter of 50 mm and a thickness of 3 mm, which was used as a test piece. .

The moisture absorption rate after leaving the test piece at 85 ° C. and 85% humidity for 72 hours was calculated by the following formula. It shows that it is excellent in moisture absorption resistance, so that the value of moisture absorption is small.
Moisture absorption rate = [{(weight of the test piece after leaving the test piece at 85 ° C. and 85% humidity for 72 hours)
− (Weight of test piece before treatment)} / (weight of test piece before treatment)] × 100

[Manufacture of epoxy resin]
<Example 1-1>
1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane (represented by the above formula (2)) heated in advance to 40 ° C. in a 2 L glass flask equipped with a stirrer, a dropping funnel and a thermometer. A phenolic compound in which R ³ and R ⁴ are methyl groups, R ³ and R ⁴ are each substituted at the 2-position, and the cyclododecyl group is bonded at the 4-position.) 170 g, isopropyl alcohol 193.3 g , Epichlorohydrin 496.6 g (6 mol per mol of 1,1-bis (4-hydroxy-3-methylphenyl) cyclododecane hydroxyl group) and 69.0 g of water were charged and heated to 40 ° C. to dissolve uniformly. After that, 85.8 g of 48% aqueous sodium hydroxide solution was added dropwise over 1.5 hours. During this time, the temperature was gradually raised, and the temperature inside the system was adjusted to 65 ° C. after the dropping was completed. Thereafter, the reaction was completed by maintaining at 65 ° C. for 0.5 hour, and by-product salt and excess sodium hydroxide were removed by washing with water. Subsequently, excess epichlorohydrin and isopropanol were distilled off from the product under reduced pressure to obtain a crude epoxy resin. This crude epoxy resin was dissolved in 330 g of methyl isobutyl ketone, added with 4.65 g of a 48 mass% aqueous sodium hydroxide solution, and reacted at a temperature of 65 ° C. for 1 hour. Thereafter, an aqueous sodium phosphate solution was added to the reaction solution to neutralize excess sodium hydroxide and washed with water to remove by-product salts. Next, methyl isobutyl ketone was completely removed under reduced pressure to obtain 210 g of an epoxy resin. About the obtained epoxy resin, the epoxy equivalent, the softening point, and the viscosity were measured. These analytical values are shown in Table-1.

<Example 1-2>
As a raw material, 1,1-bis (4-hydroxyphenyl) cyclododecane (a phenol compound represented by the formula (2), wherein R ³ and R ⁴ are hydrogen atoms) 227.7 g, isopropyl alcohol 325.5 g, epichlorohydrin 836.6 g (7 mol per 1 mol of hydroxyl group of 1,1-bis (4-hydroxyphenyl) cyclododecane) and 106.4 g of water were charged, and the mixture was heated to 40 ° C. and uniformly dissolved. Thereafter, a crude epoxy resin was obtained in the same manner as in Example 1-1 except that 123.8 g of a 48% sodium hydroxide aqueous solution was used. Further, this crude epoxy resin was dissolved in 450 g of methyl isobutyl ketone, and reacted with addition of 6.34 g of a 48 mass% sodium hydroxide aqueous solution, in the same manner as in Example 1-1, and 276 g of the target epoxy resin. Got. About the obtained epoxy resin, the epoxy equivalent, the softening point, and the viscosity were measured. These measurement results are shown in Table-1.

<Comparative Example 1-1>
As raw materials, 211.7 g of 1,1-bis (4-hydroxyphenyl) cyclohexane (bisphenol Z), 397.5 g of isopropyl alcohol, 1021.8 g of epichlorohydrin (1 mol of hydroxyl group of 1,1-bis (4-aminophenyl) cyclohexane 6 mol) and 123.3 g of water were charged, and the mixture was heated to 40 ° C. and dissolved uniformly. Then, the crude product was obtained in the same manner as in Example 1-1 except that 151.2 g of 48% aqueous sodium hydroxide solution was used. An epoxy resin was obtained. Further, 260 g of the target epoxy resin was obtained in the same manner as in Example 1-1 except that this crude epoxy resin was dissolved in 450 g of methyl isobutyl ketone and reacted by adding 6.34 g of a 48 mass% sodium hydroxide aqueous solution. Got. The epoxy resin obtained here is similar to the epoxy resin described in Example 1 of JP-A-2007-254579. About the obtained epoxy resin, the epoxy equivalent, the softening point, and the viscosity were measured. These measurement results are shown in Table-1.

<Comparative Example 1-2 and Comparative Example 1-3>
In Comparative Example 1-2, a bisphenol A type epoxy resin (JER (registered trademark) 828US manufactured by Mitsubishi Chemical Corporation) was used, and in Comparative Example 1-3, a hydrogenated bisphenol A type epoxy resin (Mitsubishi Chemical ( Co., Ltd. JER (registered trademark) YX8000) was used. About these, the epoxy equivalent, the softening point, and the viscosity were measured. These measurement results are shown in Table-1.

[Production of epoxy resin composition and cured product]
<Example 2-1>
100 parts by weight of the epoxy resin (epoxy equivalent: 257 g / equivalent, softening point: 94 ° C.) obtained in Example 1-1, methylhexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., trade name) as an acid anhydride curing agent : MH-700, acid anhydride equivalent 165 g / equivalent))) 64 parts by weight until uniform at a temperature of 110 ° C., followed by methyltributylphosphonium dimethyl phosphate (manufactured by Nippon Chemical Industry Co., Ltd., trade name; 1.0 part by weight of Hishicolin PX-4MP) was added, stirred and dissolved to obtain an epoxy resin composition. After defoaming this epoxy resin composition under reduced pressure, it was poured into a mold for preparing a test piece for each evaluation test and cured in an oven at 100 ° C. for 3 hours and then at 140 ° C. for 3 hours to obtain a cured product. Obtained. The evaluation results of this cured product are shown in Table-2.

<Example 2-2, Comparative Examples 2-2 to 2-4>
Except having changed the kind of epoxy resin and the compounding quantity of an acid anhydride type hardening | curing agent as shown in Table 1, operation similar to Example 2-1 was performed respectively and the epoxy resin composition was obtained. Moreover, the hardened | cured material was obtained similarly to Example 2-1. The evaluation results of each cured product are shown in Table-2.

[Evaluation of results]
From the results of Table 1, the epoxy resin of Comparative Example 1-1 is semi-solid, while the epoxy resins of Comparative Example 1-2 and Comparative Example 1-3 are liquid, whereas Examples 1-1 and 1 -2 epoxy resin had a softening point of 30 ° C. or higher and was solid. Therefore, it turns out that the epoxy resin of Example 1-1 and 1-2 is excellent in the handleability compared with the epoxy resin of Comparative Examples 1-1 to 1-3.

  Next, from the results of Table 2, it can be seen that Examples 2-1 and 2-2 using the epoxy resin of the present invention are excellent in all of heat resistance, heat deterioration resistance and moisture absorption resistance. On the other hand, Comparative Example 2-1 has poor heat resistance and heat deterioration resistance, Comparative Example 2-2 has poor heat resistance, heat deterioration resistance and moisture absorption resistance, and Comparative Example 2-3 has heat resistance. It is clear that the heat deterioration resistance is poor.

  The epoxy resin of the present invention and the epoxy resin composition containing the epoxy resin are excellent in cured product properties such as heat resistance, heat deterioration resistance, and moisture absorption resistance, and the epoxy resin of the present invention is also excellent in handleability. For this reason, light emitting devices such as LEDs and organic ELs; light receiving devices such as solar cells, CCDs, infrared sensors, and pickup lenses; particularly in applications of various optical members such as optical power distribution plates, optical connectors, and optical semiconductor-related members such as lenses. Although useful, the use is not limited to these, and can be suitably applied to various uses such as adhesives, paints, materials for civil engineering and construction, and insulating materials for electric / electronic parts.

Claims (8)

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

(In the above formula (1), A includes the chemical structure represented by the above formula (2), R is a hydrogen atom or a group represented by the above formula (3), and n is the average number of repetitions. Yes and no greater than 0 and no greater than 150. In the above formula (2), R ^{1 to} R ⁴ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. An epoxy resin obtained by reacting a phenol compound represented by the following formula (4) with epihalohydrin.

(In the above formula (4), R ^{1 ′ to} R ^{4 ′} may be different from each other, and are a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.)   The epoxy resin of Claim 1 or 2 whose epoxy equivalent is 200-30,000 g / equivalent.   An epoxy resin composition comprising the epoxy resin according to any one of claims 1 to 3 and a curing agent.   The epoxy resin composition according to claim 4, comprising 0.01 to 200 parts by weight of the curing agent with respect to 100 parts by weight of the epoxy resin.   The said hardening | curing agent is at least 1 of the group which consists of an acid anhydride type hardening | curing agent, a cationic polymerization initiator, an organic phosphorus compound, an amine type hardening | curing agent, and a tertiary amine, The Claim 4 or 5 Epoxy resin composition.   Hardened | cured material formed by hardening | curing the epoxy resin composition of any one of Claims 4 thru | or 6.   An optical member comprising the epoxy resin composition according to any one of claims 4 to 6.