JP2017155127A - Curable epoxy resin composition and cured product of the same, and electric/electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable epoxy resin composition which is excellent in curability, insulating reliability, heat resistance and moisture absorbing properties based on an epoxy resin that has a small amount of hydrolyzable chlorine and has a high crystallization rate, and to provide a cured product of the same.SOLUTION: There are provided a cured product which contains an epoxy resin that contains a structural unit derived from an epoxy compound having a biphenyl structure represented by formula (1) and has an epoxy equivalent of 223-241 g/eq, and a polyfunctional acid anhydride curing agent; a cured product formed by curing the same; and an electric/electronic component formed of the cured product.SELECTED DRAWING: None

Description

  The present invention is a curable epoxy that has low hydrolyzable chlorine content, excellent insulation reliability, high crystallization speed, and high productivity including an epoxy resin with excellent productivity, insulation reliability, moisture absorption, and heat resistance. The present invention relates to a resin composition, a cured product obtained therefrom, and an electric / electronic component comprising the cured product.

  Epoxy resins can be cured with various curing agents, resulting in a cured product with excellent mechanical properties, heat resistance, electrical properties, etc., and can be used in a wide range of fields such as adhesives, paints, and electrical / electronic materials. It's being used. In particular, epoxy resins are widely used in the field of electrical and electronic materials, taking advantage of the characteristics of handling properties, insulating properties, heat resistance, hygroscopicity, and adhesiveness.

In addition, with recent downsizing and thinning of electronic components, the required performance for these applications has become more severe and diverse. For example, for epoxy resins, the wiring of electronic components In order to obtain a higher degree of insulation reliability, the reduction in the amount of chlorine contained in the resin is required.
In addition to this, in order to improve the productivity of electronic devices, it is required to improve the crystallization speed of the encapsulant, and in the epoxy resin composition and cured product, even in severer high temperature and high humidity environment, There is a demand for improvement in insulation reliability, heat resistance, hygroscopicity, etc. so that the device can be used.

  Patent Document 1 describes glycidyl ether of 4-phenylphenol, but the epoxy equivalent is higher than that of the present invention. Further, glycidyl ether of 4-phenylphenol has been studied as an epoxy acrylate, and has not been studied as an epoxy resin, an epoxy resin composition, or a cured product.

JP 2005-314512 A

An object of the present invention is to provide a curable epoxy resin composition excellent in curability, insulation reliability, heat resistance, and hygroscopicity based on an epoxy resin having a small amount of hydrolyzable chlorine and a high crystallization rate, and a cured product thereof. Is an offer.
Such a curable epoxy resin composition and its cured product are suitably used for electric / electronic parts.

As a result of intensive studies to solve the above problems, the present inventor, as a result, contains a structural unit derived from a specific epoxy compound, an epoxy resin having an epoxy equivalent of 223 to 241 g / eq, and a curing containing a polyfunctional curing agent. The present invention has been completed by finding that a functional epoxy resin composition can solve the above problems.
That is, the gist of the present invention resides in the following [1] to [7].
[1] An epoxy resin containing a structural unit derived from an epoxy compound represented by the following formula (1) and having an epoxy equivalent of 223 to 241 g / eq (hereinafter referred to as “biphenyl-based epoxy resin”), and a polyfunctional acid anhydride A curable epoxy resin composition comprising a product curing agent.

[2] The curable epoxy resin composition according to the above [1], wherein the hydrolyzable chlorine of the biphenyl epoxy resin is 1000 ppm or less.
[3] The curable epoxy resin composition according to the above [1] or [2], wherein the biphenyl epoxy resin has a melting point of 73 to 76 ° C.
[4] The curable epoxy resin composition according to any one of [1] to [3], wherein the content of the polyfunctional acid anhydride curing agent is 0.01 to 100 parts by weight per 100 parts by weight of the epoxy resin.
[5] A cured product obtained by curing the curable epoxy resin composition according to any one of [1] to [4].
[6] An electric / electronic component comprising the cured product according to [5].

According to the present invention, an epoxy resin with low hydrolyzable chlorine content and excellent insulation reliability, high crystallization speed and excellent productivity, and curability, insulation reliability, hygroscopicity, heat resistance based on this epoxy resin A curable epoxy resin composition having excellent properties and a cured product thereof are provided.
The curable epoxy resin composition of the present invention has the above-described properties, and can be particularly effectively applied to electric / electronic parts such as a semiconductor sealing material and a laminated board.

Hereinafter, embodiments of the present invention will be described in detail. However, the following description is an example of embodiments of the present invention, and the present invention is not limited to the following description unless it exceeds the gist. Absent.
In addition, when using the expression “to” in the present specification, it is used as an expression including numerical values or physical property values before and after the expression.
Hereinafter, the constituent requirements of the present invention will be described in detail in the order of the main component of the epoxy resin, the method for producing the epoxy resin, the curable epoxy resin composition of the present invention, the curing reaction and the cured product, and the use of the cured product. To do.

1. Biphenyl Epoxy Resin (1) Features The epoxy resin used in the present invention is an epoxy resin containing a structural unit derived from an epoxy compound represented by the following formula (1) (hereinafter sometimes referred to as “biphenyl epoxy resin”). The amount of hydrolyzable chlorine is low, the insulation reliability is excellent, the crystallization rate is high, and the productivity is excellent.

This biphenyl epoxy resin has less hydrolyzable chlorine, so free chlorine when cured is reduced, preventing wiring corrosion of electrical and electronic equipment and preventing problems such as poor insulation. .
(2) Epoxy equivalent In the present invention, “epoxy equivalent” is used as a measure of the number of epoxy groups contained in the biphenyl-based epoxy resin. “Epoxy equivalent” is defined as “mass of epoxy resin containing 1 equivalent of epoxy group” and can be measured according to JIS K7236.

The epoxy equivalent of the biphenyl epoxy resin used in the present invention is required to be 223 to 241 g / eq (“eq” means “equivalent”), and by making the epoxy equivalent within this range, A sufficiently fast crystallization rate, which is an effect, can be obtained.
By setting the epoxy equivalent to 230 to 241 g / eq, since the crystallization speed is further increased, the productivity at the time of commercialization by pulverization of the epoxy resin can be further improved, which is more preferable.

In order to set the epoxy equivalent to 223 g / eq or more, the alkali concentration during the dechlorination reaction is increased, the resin content during the reaction is increased, the reaction temperature is increased and / or the reaction time is increased. The oligomerization of the epoxy compound of the above formula (1) may be advanced to obtain a desired epoxy equivalent.
In order to set the epoxy equivalent to 241 g / eq or less, contrary to the above, the alkali concentration during the dechlorination reaction is lowered, the resin content during the reaction is lowered, the reaction temperature is lowered and / or the reaction is performed. An operation such as shortening the time may be performed.
The progress of the oligomerization reaction can be confirmed by sampling timely during the reaction and measuring the epoxy equivalent.

(3) Hydrolyzable chlorine content The biphenyl-based epoxy resin preferably has a hydrolyzable chlorine content (hereinafter sometimes referred to as "hydrolyzable chlorine content") of 1000 ppm or less.
The smaller the amount of hydrolyzable chlorine, the better in terms of the electrical reliability and the like of the product obtained, and more preferably 490 ppm or less. The lower limit of the amount of hydrolyzable chlorine is 0 ppm, that is, “below the detection limit” in the measurement of the amount of hydrolyzable chlorine described below. Therefore, the lower limit of the amount of hydrolyzable chlorine is usually 10 ppm, more preferably 1 ppm.
As a method for measuring the amount of hydrolyzable chlorine, for example, about 0.5 g of a precisely weighed epoxy resin is dissolved in 20 ml of dioxane, refluxed with 5 ml of 1N KOH / ethanol solution for 30 minutes, and then with 0.01N silver nitrate solution. The method of quantifying by titration is mentioned.

(4) Melting point The melting point of the biphenyl-based epoxy resin of the present invention is preferably 73 to 76 ° C from the viewpoint of crystallization speed, and 73 to 75 ° C to shorten the reaction time during the production of the epoxy resin. It is more preferable because it is possible.
In the present invention, the “melting point” is a melting point measured by raising the temperature from 30 ° C. to 150 ° C. at 1 ° C./min using a differential scanning calorimeter (DSC: EXSTAR 7020 manufactured by Seiko Instruments Inc.). .

(5) Crystallization speed The epoxy resin of the present invention has a high crystallization speed and excellent productivity. In the present invention, the superiority or inferiority of the “crystallization rate” was evaluated by the following procedure.
<Evaluation method of crystallization rate>
20 g of epoxy resin was weighed into a 50 cc vial, heated to 150 ° C. to completely melt the epoxy resin, and stored at 23 ° C. for 1 hour. After 1 hour, the crystallized crystal in the vial was “◯”, and the crystallized crystal was “X”.

2. Method for Producing Biphenyl Epoxy Resin The method for producing the biphenyl epoxy resin of the present invention, in which the epoxy equivalent, the amount of hydrolyzable chlorine, and the melting point satisfy the above-mentioned conditions, will be described below. The biphenyl epoxy resin used in the present invention The production method is not limited to the following production method as long as the obtained epoxy resin satisfies the above-mentioned conditions.
As a method for producing a biphenyl-based epoxy resin, a one-step production method using 4-phenylphenol represented by the following formula (2) (hereinafter sometimes referred to as “4PP”) as a raw material, or via an allylated product of 4PP The method of doing can be illustrated.

(1) Production of biphenyl-based epoxy resin The epoxy equivalent, hydrolyzable chlorine amount, and melting point of the biphenyl-based epoxy resin of the present invention satisfying the aforementioned preferred ranges are not particularly limited as described above. Examples thereof include a production method by a one-step method described below and a production method via an allylation reaction. These methods are described in detail below.

<Production method by one-step method>
In the one-stage production method, the biphenyl epoxy resin of the present invention can be produced by reacting the phenol compound (4PP) of the formula (2) with epihalohydrin.

In producing the epoxy resin by the above method, other polyvalent hydroxy compounds may be used as raw materials in addition to 4PP. In this case, in addition to the biphenyl type epoxy resin of the present invention, other epoxy resins are also produced.
However, even in the above case, in accordance with the gist of the present invention, the ratio of 4PP in the raw material hydroxy compound is preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 80 mol% or more. . Particularly preferred is 100 mol%.

In the present invention, “hydroxy compound” in “polyhydric hydroxy compound” and the like is a generic term including both a phenol compound and an alcohol compound.
Examples of the other polyvalent hydroxy compounds include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, bisphenol AF, hydroquinone, resorcin, methylresorcin, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol Novolak resin, cresol novolak resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolak resin, naphthol novolak resin, brominated bisphenol A, brominated phenol novolak resin, etc. Various polyphenols (except 4PP of the above formula (2)) , Polyhydric phenol resins obtained by condensation reaction of various phenols with various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, glyoxal, etc., polyhydric phenol resins obtained by condensation reaction of xylene resin and phenols , Various phenol resins such as co-condensation resin of heavy oil or pitches and phenols and formaldehyde, ethylene glycol, trimethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol Chain aliphatic diols such as 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol and 1,6-hexanediol; cycloaliphatic diols such as cyclohexanediol and cyclodecanediol Polyethylene ether Recall, polyoxytrimethylene ether glycols, polyalkylene ether glycols such as polypropylene ether glycol and the like.

  Among these, phenol novolak resin, phenol aralkyl resin, polyhydric phenol resin obtained by condensation reaction of phenol and hydroxybenzaldehyde, biphenyl aralkyl resin, naphthol aralkyl resin, ethylene glycol, trimethylene glycol, propylene glycol, Chain aliphatic diols such as 1,3-butanediol, 1,4-butanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, Cycloaliphatic diols such as cyclohexanediol and cyclodecanediol, and polyalkylene ether glycols such as polyethylene ether glycol, polyoxytrimethylene ether glycol, and polypropylene ether glycol Le, and the like can be mentioned.

  4PP used as a raw material and other polyvalent hydroxy compounds used as necessary are generally 0.8 to 20 equivalents, preferably 0.9 to 15 equivalents per one equivalent of hydroxyl groups of all hydroxy compounds as the total. More preferably, it is dissolved in an amount of epihalohydrin corresponding to 1.0 to 10 equivalents to obtain a uniform solution. It is preferable that the amount of epihalohydrin is 0.8 equivalent or more because the oligomerization reaction can be easily controlled and the resulting epoxy resin can have an appropriate melt viscosity and epoxy equivalent. On the other hand, when the amount of epihalohydrin is 20 equivalents or less, production efficiency tends to be improved, which is preferable.

In addition, as epihalohydrin in this reaction, epichlorohydrin or epibromohydrin is usually used.
Next, while stirring the above solution, it is usually 0.5 to 2.0 equivalents, preferably 0.7 to 1.8 equivalents, more preferably 0.9 to 1 equivalent per hydroxyl group equivalent of the starting hydroxy compound. An amount of alkali metal hydroxide corresponding to 6 equivalents is added as a solid or an aqueous solution and reacted. It is preferable that the amount of the alkali metal hydroxide is 0.5 equivalent or more because the unreacted hydroxyl group and the generated epoxy resin are difficult to react and the high molecular weight reaction is easily controlled. Moreover, it is preferable to make the amount of the alkali metal hydroxide not more than 2.0 equivalents because the generation of impurities due to side reactions can be suppressed. As the alkali metal hydroxide used here, sodium hydroxide or potassium hydroxide is usually used.

  This reaction can be carried out under normal pressure or reduced pressure, and the reaction temperature is usually 40 to 150 ° C., preferably 60 to 100 ° C., more preferably 80 to 100 ° C. A reaction temperature of 40 ° C. or higher is preferable because the reaction easily proceeds and the reaction can be easily controlled. Further, it is preferable that the reaction temperature is 150 ° C. or lower because side reactions can be suppressed and chlorine impurities are particularly easily reduced.

  In the epoxy resin production reaction, the reaction liquid is azeotroped while maintaining a predetermined temperature as necessary, and the condensate obtained by cooling the vaporized vapor is separated into oil / water to return the oil to the reaction system. It is carried out while dehydrating by the method. In order to suppress a rapid reaction, the alkali metal hydroxide as a catalyst is usually intermittently little by little over 0.1 to 8 hours, preferably 0.1 to 7 hours, more preferably 0.5 to 6 hours. Or add continuously. By setting the addition time of the alkali metal hydroxide to 0.1 hour or longer, the rapid progress of the reaction can be prevented and the reaction temperature can be easily controlled. By making the addition time 8 hours or less, the generation of chlorine impurities can be reduced, and it is also preferable from the viewpoint of economy.

The total reaction time for this reaction is usually 1 to 15 hours. After completion of the reaction, by-product insoluble salts are removed by filtration and / or washing with water, and then the unreacted epihalohydrin is distilled off under reduced pressure to obtain a crude epoxy resin.
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.

  In addition, 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 polar solvents such as dimethyl sulfoxide and dimethylformamide; An inert organic solvent may be used as the reaction medium.

<Production method via allylation reaction>
Biphenyl type epoxy resin can also be manufactured by the method via an allylation reaction. In this case, the crude epoxy resin can be obtained by performing an allylation reaction on 4PP, which is a phenolic compound, to introduce an allyl group, and then oxidizing the allyl group.
As a production method via an allylation reaction, the methods described in JP2011-225711A, JP2012-092247A, JP2012-111858A, etc. are used except that 4PP is used as a raw material. Can be used.

(2) Purification of crude epoxy resin The crude epoxy resin obtained above contains chlorine-based impurities such as chlorine and chlorine-containing compounds produced by the reaction of unreacted raw material compounds and epihalohydrins. A purified epoxy resin can be obtained by reacting such a chlorine-based impurity with a strong alkali to convert the contained chlorine into an inorganic chlorine-based water-soluble compound, followed by washing with water.

  In this purification process, due to differences in the purity and manufacturing conditions of the crude epoxy resin, or the processing (reaction) conditions in the purification process, the degree of purification (hydrolyzable chlorine content, total chlorine content) Etc.) may be different. For this reason, in order to obtain an epoxy resin having a desired degree of purification, it is preferable to perform sampling at any time and analyze the epoxy equivalent, viscosity, chlorine content, and the like.

  In order to remove the residual chlorine compound component in the crude epoxy resin, a method of reacting with a strong alkali is common. In this reaction, an organic solvent for dissolving the crude epoxy resin may be used. The organic solvent used in the reaction is not particularly limited, but an aprotic polar solvent and / or an inert organic solvent other than the aprotic polar solvent is used from the viewpoints of purification efficiency, handleability, workability, and the like. It is preferable to use it individually or in mixture.

  Examples of the aprotic polar solvent include dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, sulfolane, dimethylformamide, dimethylacetamide, hexamethylphosphoramide and the like. These may be used alone or in combination of two or more. Among these aprotic polar solvents, dimethyl sulfoxide is preferable because it is easily available and has excellent effects.

  Examples of the inert organic solvent other than the aprotic polar solvent include aromatic hydrocarbon solvents such as benzene, toluene, and xylene, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, dioxane, and ethylene glycol dimethyl ether. Although ethers are mentioned, aromatic hydrocarbon solvents or ketone solvents are preferable from the viewpoint of washing effect and ease of post-treatment, and toluene, xylene or methyl isobutyl ketone is particularly preferable. These may be used alone or in combination of two or more.

When the aprotic polar solvent is mixed with an inert organic solvent other than the above, the proportion of the aprotic polar solvent in the total solvent is preferably 3 to 20% by weight.
The amount of the organic solvent used is such that the concentration of the crude epoxy resin is usually 3 to 70% by weight, preferably 5 to 50% by weight, more preferably 10 to 40% by weight. is there.

By making the usage-amount of an organic solvent into the said range, the removal efficiency of a residual chlorine compound component can be made favorable.
As a strong alkali component used here, alkali metal hydroxides, such as potassium hydroxide and sodium hydroxide, can be used as a solid or a solution. These alkali metal hydroxides may be used by dissolving in water or an organic solvent. The amount of the alkali metal hydroxide used is preferably 0.01 parts by weight or more and 2.0 parts by weight or less in terms of solid content of the alkali metal hydroxide with respect to 100 parts by weight of the crude epoxy resin.

Although the reaction temperature of the said reaction is based also on the boiling point of the solvent to be used, it is 30-120 degreeC normally, Preferably it is 40-110 degreeC. By setting the reaction temperature within this range, the reaction can be proceeded mildly with good controllability.
Moreover, reaction time is 0.1 to 15 hours normally, Preferably it is 0.3 to 12 hours. By making reaction time into the said range, reaction can be advanced, preventing the excessive progress of reaction.

After the reaction, excess alkali metal hydroxide or by-product salt can be removed by a method such as washing with water, and the organic solvent can be removed by distillation under reduced pressure and / or steam distillation.
By passing through the above purification steps, an epoxy resin having an epoxy equivalent of 223 to 241 g / eq, preferably having a hydrolyzable chlorine of 1000 ppm or less and a melting point of 73 to 76 ° C. can be obtained.

3. Curable Epoxy Resin Composition (1) Features of Curable Epoxy Resin Composition The curable epoxy resin composition of the present invention contains the specific biphenyl epoxy resin and the polyfunctional acid anhydride curing agent described above. is there.
Such an epoxy resin composition containing a polyfunctional acid anhydride curing agent having two or more acid anhydride groups in one molecule has good curability even if it does not contain a polyfunctional epoxy resin as an epoxy resin. The obtained cured product can have excellent heat resistance, stress resistance, hygroscopicity, flame retardancy, and the like.

  In the curable epoxy resin composition of the present invention, in addition to the above-mentioned components, if necessary, other epoxy resins other than the biphenyl epoxy resin of the present invention (hereinafter simply referred to as “other epoxy resins”) And a curing agent other than the polyfunctional acid anhydride curing agent, a curing accelerator, an inorganic filler, a coupling agent, and the like can be appropriately mixed as long as the gist and effect of the present invention are not impaired.

The curable epoxy resin composition of the present invention has the characteristics that the main component biphenyl-based epoxy resin has a low hydrolyzable chlorine content and a high crystallization speed, and thus has excellent curability. The cured product obtained from the composition has excellent properties such as insulation reliability, hygroscopicity, and heat resistance, and can be suitably used for various applications including electric and electronic parts.
Hereinafter, essential components and optional components constituting the composition of the present invention other than the biphenyl-based epoxy resin will be described individually.

(2) Multifunctional acid anhydride curing agent The polyfunctional acid anhydride curing agent, which is an essential component in the present invention, contains an acid anhydride group that contributes to a crosslinking reaction and / or chain extension reaction between epoxy groups of an epoxy resin. A compound having a plurality in one molecule.
In the curable epoxy resin composition of the present invention, the content of the polyfunctional acid anhydride curing agent is preferably 0.01 to 1000 parts by weight with respect to 100 parts by weight (solid content) of all epoxy resin components. .

  If the content of the polyfunctional acid anhydride curing agent is less than 0.01 parts by weight, an excessive amount of time is required to cure the epoxy resin composition, which is not practical. On the other hand, if a polyfunctional curing agent is used in such a large amount that the content exceeds 1000 parts by weight, the curing reaction of the epoxy resin becomes extremely fast, and the molded product becomes non-uniform or easily distorted. In some cases, a large amount of polyfunctional acid anhydride curing agent that does not contribute to the curing reaction remains in the cured product, resulting in stickiness on the surface of the molded product or a desired hardness may not be obtained.

The upper limit of the content of the polyfunctional acid anhydride curing agent is preferably 500 parts by weight, and more preferably 300 parts by weight. A particularly preferred upper limit is 100 parts by weight. When used in such an amount, low molecular components contained as impurities in the polyfunctional acid anhydride curing agent can be prevented from bleeding from the cured product.
Further, the lower limit of the content of the polyfunctional acid anhydride curing agent is preferably 0.5 parts by weight, and more preferably 1 part by weight. By setting it as such quantity, desired hardness can be obtained more rapidly.

  In the present invention, the “solid content” means a component excluding a solvent, and includes not only a solid epoxy resin but also a semi-solid or viscous liquid epoxy resin. Further, the “total epoxy resin component” corresponds to the amount of the epoxy resin contained in the curable epoxy resin composition of the present invention, and when the curable epoxy resin composition contains only the biphenyl-based epoxy resin of the present invention, It means the amount of biphenyl type epoxy resin, and when biphenyl type epoxy resin and other epoxy resins are included, it corresponds to the total amount of biphenyl type epoxy resin and other epoxy resins.

  Examples of the polyfunctional acid anhydride curing agent preferably used in the present invention include pyromellitic acid anhydride, benzophenone tetracarboxylic acid anhydride, poly (ethyloctadecanedioic acid) anhydride, and poly (phenylhexadecanedioic acid) anhydride. , Methylcyclohexene tetracarboxylic acid anhydride, ethylene glycol bis trimellitate dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid anhydride 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 1-methyl-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid An anhydride etc. are mentioned.

  Examples of modified acid anhydrides include those obtained by modifying the above acid anhydride with glycol. Here, 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 pothitetramethylene ether glycol. It is done. Furthermore, a copolymer polyether glycol 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 group. When the modification amount is not more than the above upper limit, the viscosity of the curable epoxy resin composition does not become too high, the workability tends to be good, and the speed of the curing reaction with the epoxy resin also tends to be good. It is in.
The polyfunctional acid anhydride curing agents mentioned above may be used alone or in combination of two or more in any combination and blending ratio.

  When the above polyfunctional acid anhydride curing agent is used, the equivalent ratio of the functional group in the curing agent to the epoxy group contained in all epoxy resin components of the curable epoxy resin composition is 0.8 to 1.5. It is preferable to use it within the range. Within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain, which is preferable.

(3) Other curing agents In the present invention, in addition to the polyfunctional acid anhydride curing agent, other curing agents may be used in combination. Further, even compounds that are usually called “curing accelerators” are compounds that contribute to the crosslinking reaction and / or chain extension reaction between the epoxy groups of the epoxy resin, and those that meet the above conditions can also be used.

The combination and amount used in the case of using other curing agents as described above are not particularly limited as long as the effects of the polyfunctional acid anhydride curing agent are not inhibited, and the amount of the polyfunctional acid anhydride curing agent used is not limited. What is necessary is just to decide to use in the form which replaces a part within the range.
As other curing agents, those generally known as curing agents for epoxy resins can be used without particular limitation as long as the above conditions are satisfied. For example, amine curing agents such as phenolic curing agents, aliphatic amines, polyether amines, alicyclic amines, aromatic amines, monofunctional acid anhydride curing agents, amide curing agents, tertiary amines, Examples include imidazoles.

Moreover, when using multiple types of curing agents, they may be used after mixing and preparing a mixed curing agent in advance, and each component of the curing agent may be used when mixing each component of the curable epoxy resin composition. They may be added separately and mixed.
Hereinafter, the curing agent exemplified above will be described in more detail.

<Phenolic curing agent>
Specific examples of the phenolic curing agent include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, hydroquinone, resorcin, methylresorcin, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thiodiphenols, phenol novolac resin, Cresol novolak resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolak resin, trisphenol methane type resin, naphthol novolak resin, brominated bisphenol A, brominated phenol novolak Various polyphenols such as resins, various phenols and benzalde , Polyhydric phenol resins obtained by condensation reaction with various aldehydes such as hydroxybenzaldehyde, crotonaldehyde, glyoxal, polyhydric phenol resins obtained by condensation reaction of xylene resin and phenols, heavy oil or Co-condensation resin of pitches, phenols and formaldehyde, phenol / benzaldehyde / xylylene dimethoxide polycondensate, phenol / benzaldehyde / xylylene dihalide polycondensate, phenol / benzaldehyde / 4,4'-dimethoxide biphenyl Various phenol resins such as polycondensate and phenol / benzaldehyde / 4,4′-dihalide biphenyl polycondensate are listed.

These phenolic curing agents may be used alone or in combination of two or more in any combination and blending ratio.
Among these, from the viewpoints of the curability of the composition and the heat resistance after curing, among the phenolic curing agents, a phenol novolak resin (for example, a compound represented by the following formula (3)), a phenol aralkyl resin (for example, the following) A compound represented by the formula (4)), a biphenyl aralkyl resin (for example, a compound represented by the following formula (5)), a naphthol novolak resin (for example, a compound represented by the following formula (6)), a naphthol aralkyl resin (for example, A compound represented by the following formula (7)), a trisphenolmethane type resin (for example, a compound represented by the following formula (8)), a phenol / benzaldehyde / xylylene methoxide polycondensate (for example, the following formula (9)) Compound), phenol / benzaldehyde / xylylene dihalide polycondensate (for example, represented by the following formula (9)) Compound), phenol-benzaldehyde-4,4'-dimethoxide biphenyl polycondensate (for example, a compound represented by the following formula (10)), phenol-benzaldehyde-4,4'-dihalide biphenyl polycondensate (for example, A compound represented by the following formula (10)) is preferable, and in particular, a phenol novolak resin (for example, the following formula (3)), a phenol aralkyl resin (for example, the following formula (4)), and a biphenyl aralkyl resin (for example, the following formula (5)). ), Phenol / benzaldehyde / xylylene dimethoxide polycondensate (for example, the following formula (9)), phenol / benzaldehyde / xylylene dihalide polycondensate (for example, the following formula (9)), phenol / benzaldehyde / 4,4′- Dimethoxide biphenyl polycondensate (for example, the following formula (10)), phenol - benzaldehyde 4,4' dihalide biphenyl polycondensate (e.g. following formula (10)) are preferred.

(However, in the above formulas (3) to (8), k _{1 to} k ₆ each represents a number of 0 or more.)

(However, in the above formulas (9) and (10), k ₇ , k ₈ , l ₁ , and l ₂ each represent a number of 1 or more.)

<Amine-based curing agent>
Examples of amine-based curing agents include curing agents other than tertiary amines, such as aliphatic amines, polyether amines, alicyclic amines, and aromatic amines.
Curing agents other than tertiary amines are listed below.
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, diaminodiethyl Dimethyldiphenylmethane, α, α'-bis (4-
Aminophenyl) -p-diisopropylbenzene and the like are exemplified.
The amine-based curing agents (other than tertiary amines) mentioned above may be used alone or in combination of two or more in any combination and mixing ratio.

<Monofunctional acid anhydride curing agent>
In the present invention, a monofunctional acid anhydride curing agent that does not correspond to the essential polyfunctional acid anhydride curing agent can be used in combination. Examples of such monofunctional acid anhydride curing agents include monofunctional acid anhydrides and modified products thereof.

  Examples of monofunctional acid anhydrides include phthalic acid anhydride, trimellitic acid anhydride, dodecenyl succinic acid anhydride, polyadipic acid anhydride, polyazeline acid anhydride, polysebacic acid anhydride, tetrahydrophthalic acid anhydride, methyl Tetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride, hexahydrophthalic anhydride, methyl hymic acid anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, het acid anhydride, nadic acid An anhydride, a methyl nadic acid anhydride, etc. are mentioned.

Examples of modified acid anhydrides include those obtained by modifying the above acid anhydride with glycol. As the type and amount of the modifying glycols, those described in the section of the polyfunctional acid anhydride curing agent can be used in the same manner.
The monofunctional acid anhydride curing agents listed above can be used alone or in combination of two or more in any combination and blending amount.

<Amide-based curing agent>
Examples of the amide-based curing agent include dicyandiamide and derivatives thereof, and polyamide resins. Such amide type curing agents may be used alone or in a combination of two or more in any combination and ratio.

<Imidazoles>
Examples of imidazoles include 2-phenylimidazole, 2-ethyl-4 (5) -methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1 -Cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino- 6- [2′-Methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s -Triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-tri Azine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and an epoxy resin and the above imidazoles Examples include adducts.

In addition, since imidazoles have catalytic ability, they can generally be classified as curing accelerators, but in the present invention, they are classified as curing agents.
The imidazoles listed above may be used alone or in combination of two or more in any combination and ratio.

(4) Other epoxy resins In addition to the biphenyl-based epoxy resin, the curable epoxy resin composition of the present invention is combined with other monofunctional or polyfunctional epoxy resins as long as the purpose and effect of the present invention are not impaired. Can be used. By including other epoxy resins, the heat resistance, adaptability, moisture resistance, flame retardancy, etc. of the curable epoxy resin composition of the present invention can be improved.

Examples of other epoxy resins that can be used in the curable epoxy resin composition of the present invention include the following epoxy resins.
For example, bisphenol A type epoxy resin, trisphenol methane type epoxy resin, anthracene type epoxy resin, phenol modified xylene resin type epoxy resin, bisphenol cyclododecyl type epoxy resin, bisphenol diisopropylidene resorcinol type epoxy resin, bisphenol F type epoxy resin, Bisphenol AD 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, biphenol type epoxy resin, tetramethyl biphenol type epoxy resin, tetramethylbisphenol F Type epoxy resin, dihydroxydiphenyl ether type epoxy resin, derived from thiodiphenols Epoxy resin, dihydroxynaphthalene type epoxy resin, dihydroxyanthracene type epoxy resin, dihydroxydihydroanthracene type epoxy resin, dicyclopentadiene type epoxy resin, epoxy resin derived from dihydroxystilbenes, phenol novolac type epoxy resin, cresol novolac type epoxy resin Bisphenol A novolak type epoxy resin, naphthol novolak type epoxy resin, phenol aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, terpene phenol type epoxy resin, dicyclopentadiene phenol type epoxy resin, phenol hydroxybenzaldehyde Epoxy resin derived from the condensation product of phenol, crotonal Epoxy resin derived from condensate of hydride, epoxy resin derived from condensate of phenol / glyoxal, epoxy resin derived from co-condensation resin of heavy oil or pitches with phenols and formaldehyde, diaminodiphenylmethane And epoxy resins derived from aminophenols, epoxy resins derived from aminophenols, epoxy resins derived from xylenediamine, epoxy resins derived from methylhexahydrophthalic acid, epoxy resins derived from dimer acid, and the like.

These may be used alone, or two or more may be used in any combination and mixing ratio.
Among these epoxy resins, bisphenol A-type epoxy resins, tetramethylbiphenol-type epoxy resins, 4,4 ′, in terms of improving the fluidity of the composition and the heat resistance, moisture absorption resistance, flame resistance, etc. of the cured product -Biphenol type epoxy resins, biphenyl aralkyl type epoxy resins, phenol aralkyl type epoxy resins, dihydroxyanthracene type epoxy resins, dicyclopentadiene type epoxy resins, orthocresol novolac type epoxy resins, and trisphenol methane type epoxy resins are preferred.

  When the curable epoxy resin composition of the present invention contains the above-mentioned other epoxy resin, the content is 0.01 to 99.9 wt% when the total epoxy resin component in the composition is 100 wt%. Part is preferable, more preferably 25 to 90% by weight, still more preferably 50 to 87.5% by weight.

(4) Other composition components <Curing accelerator>
The curable epoxy resin composition of the present invention preferably contains a curing accelerator. By containing a curing accelerator, the curing time can be shortened and the curing temperature can be lowered, and a desired cured product can be obtained more easily.

The type of curing accelerator is not particularly limited as long as it accelerates the curing reaction of the epoxy resin. Specific examples include organic phosphines, phosphorus compounds such as phosphonium salts, tetraphenylboron salts, organic acid dihydrazides. And a halogenated boron amine complex.
The following can be illustrated as a phosphorus compound which can be used as a hardening accelerator.

1) Organic phosphines: triphenylphosphine, diphenyl (p-tolyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkylalkoxyphenyl) phosphine, tris (dialkylphenyl) phosphine, tris ( Trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, etc. 2) Derivatives of organic phosphines: Complexes of the above organic phosphines with organic borons, addition of organic phosphines with other compounds Other compounds that can be used here include maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, Examples thereof include quinone compounds such as 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone and phenyl-1,4-benzoquinone, and diazophenylmethane.

3) Phosphonium salt: Examples of the phosphonium salt include compounds having a tetraphenylphosphonium salt, an alkyltriphenylphosphonium salt, and the like. Specifically, tetraphenylphosphonium thiocyanate, tetraphenylphosphonium tetra-p-methylphenylborate, butyl Examples thereof include triphenylphosphonium thiocyanate.
Of the curing accelerators exemplified above, organic phosphines and phosphonium salts are preferred, and organic phosphines are most preferred. Moreover, a hardening accelerator may be used independently, or may mix and use 2 or more types of compounds by arbitrary combinations and a ratio.

In the curable epoxy resin composition of the present invention, these curing accelerators are preferably used in the range of 0.1 to 20 parts by weight with respect to 100 parts by weight of the total epoxy resin component, The amount is more preferably 0.5 parts by weight or more, and still more preferably 1 part by weight or more. On the other hand, the upper limit is more preferably 15 parts by weight or less, and still more preferably 10 parts by weight or less.
By setting the content of the curing accelerator to be the above lower limit value or more, a good curing acceleration effect can be obtained, and by setting the content to the upper limit value or less, desired cured physical properties can be easily obtained.

<Inorganic filler>
An inorganic filler can be blended in the curable epoxy resin composition of the present invention. Examples of the inorganic filler include fused silica, crystalline silica, glass powder, alumina, calcium carbonate, calcium sulfate, talc, and boron nitride. These may be used alone or in combination of two or more in any combination and blending ratio.

  By using an inorganic filler, when the curable epoxy resin composition of the present invention is used as a semiconductor encapsulant, the thermal expansion coefficient of the semiconductor encapsulant can be brought close to the internal silicon chip or lead frame. Moreover, since the moisture absorption amount of the entire semiconductor sealing material can be reduced, the solder crack resistance can be improved. Among them, it is preferable to use a crushed and / or spherical, fused and / or crystalline silica powder filler as an inorganic filler in a curable epoxy resin composition for a semiconductor encapsulant.

The average particle diameter of the inorganic filler is usually 1 to 50 μm, preferably 1.5 to 40 μm, more preferably 2 to 30 μm. If the average particle size is not less than the above lower limit, the melt viscosity does not increase so much, and the fluidity is unlikely to decrease. Further, it is preferable that the average particle diameter is not more than the above upper limit value because the filler is not easily clogged in a narrow gap of the mold during molding, and the filling property of the material is improved and molding defects are reduced.
When an inorganic filler is used for the curable epoxy resin composition of the present invention, the amount of the inorganic filler is preferably in the range of 30 to 95% by weight of the entire curable epoxy resin composition.

<Release agent>
A release agent can be blended in the curable epoxy resin composition of the present invention. As the release agent, for example, natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, higher fatty acids such as stearic acid and zinc stearate and metal salts thereof, and hydrocarbon release agents such as paraffin may be used. it can. These may be used alone or in combination of two or more in any combination and blending ratio.

  When mix | blending a mold release agent with the curable epoxy resin composition of this invention, the compounding quantity is 0.1-5.0 normally with respect to 100 weight part of all the epoxy resin components in a curable epoxy resin composition. Part by weight, preferably 0.5 to 3 parts by weight. By making the compounding quantity of a mold release agent into the said range, since favorable mold release property can be expressed, maintaining the hardening characteristic of a curable epoxy resin composition, it is preferable.

<Coupling agent>
A coupling agent is preferably blended in the curable epoxy resin composition of the present invention. When the coupling agent is used in combination with an inorganic filler, the adhesion between the epoxy resin as a matrix and the inorganic filler can be improved. Examples of coupling agents include silane coupling agents and titanate coupling agents.

  Examples of the silane coupling agent include epoxy silanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- Aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxy Aminosilanes such as silane, mercaptosilane such as 3-mercaptopropyltrimethoxysilane, p-styryltrimethoxysilane, vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltrimethoxysilane, vinyltriethoxysilane In addition to vinyl silanes such as lanthanum and γ-methacryloxypropyltrimethoxysilane, epoxy-based, amino-based, and vinyl-based polymer type silanes can be used.

  Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri (N-aminoethyl / aminoethyl) titanate, diisopropyl bis (dioctyl phosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis ( Ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ethylene titanate It is done.

Any of these coupling agents may be used alone or in a combination of two or more in any combination and ratio.
When using a coupling agent for the curable epoxy resin composition of this invention, it is preferable that the compounding quantity shall be 0.1-3 weight part with respect to 100 weight part of all the epoxy resin components. By adjusting the blending amount of the coupling agent within the above range, the adhesion between the epoxy resin and the inorganic filler due to the coupling agent is improved, and bleeding out of the coupling agent from the resulting cured product can be suppressed. preferable.

<Other ingredients>
In the curable epoxy resin composition of the present invention, components other than those described above (may be referred to as “other components”) can be blended. Examples of such “other components” include flame retardants, plasticizers, reactive diluents, pigments, and the like, and can be appropriately blended within the scope of the gist and curing of the present invention as necessary. . However, it does not prevent at all mixing with the curable epoxy resin composition of the present invention other than the components listed above.

  Examples of the flame retardant that can be used in the curable epoxy resin composition of the present invention include halogenated flame retardants such as brominated epoxy resins and brominated phenol resins, antimony compounds such as antimony trioxide, red phosphorus, and phosphate esters. And phosphorous flame retardants such as phosphine derivatives, nitrogen flame retardants such as melamine derivatives, and inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

4). Curing reaction and cured product <Curing reaction>
The curable epoxy resin composition of the present invention has excellent curability, and the obtained cured product has excellent insulation reliability, hygroscopicity, and heat resistance.
Although the method of hardening the curable epoxy resin composition of this invention is not specifically limited, Usually, it can be made to harden | cure by the thermosetting reaction by heating. What is necessary is just to select the heating temperature at this time suitably according to the kind of hardening | curing agent to be used. For example, when the polyfunctional acid anhydride curing agent of the present invention is used, the curing temperature is usually 130 to 300 ° C.

In this curing reaction, it is possible to lower the curing temperature or increase the curing rate by adding a curing accelerator.
The reaction time of the curing reaction is usually about 1 to 20 hours, preferably 2 to 18 hours, more preferably 3 to 15 hours. By setting the reaction time within the above range, the curing reaction proceeds sufficiently, and deterioration of the resin component due to heating and heat dissipation loss during heating can be reduced.

<Hardened product>
[Insulation reliability]
The cured product obtained from the curable epoxy resin composition of the present invention has excellent insulation reliability. In particular, the fact that the amount of chlorine in the extraction water of the epoxy resin cured product is as low as 1000 ppm or less is effective in preventing electrical and electronic parts from being deteriorated in insulation under a high temperature and high humidity environment. A more preferable upper limit of the chlorine content of the extracted water is 390 ppm or less.
The smaller the amount of chlorine in the extracted water of the cured product, the better because it is possible to prevent insulation failure and short-circuiting of semiconductors due to migration of chlorine ions.
In addition, the measuring method of the chlorine amount of extracted water is described in the item of an Example.

[Hygroscopic]
The cured product obtained from the curable epoxy resin composition of the present invention is excellent in hygroscopicity. For example, the water absorption rate when a test piece of 3 cm × 3 cm thickness 5 mm is allowed to stand for 168 hr in an environment of a temperature of 85 ° C. and a humidity of 85% can be set to 1.4% or less.
The lower the moisture absorption rate of the cured product, the smaller the thermal stress due to the expansion of the absorbed water even under a high temperature environment, and the more difficult it is to crack, so that electric and electronic parts can be used in a more severe environment.
The hygroscopic measurement / evaluation method is described in the Examples section.

[Heat-resistant]
The cured product obtained from the curable epoxy resin composition of the present invention has excellent heat stress resistance, and can have an elastic modulus at 200 ° C. of 84 MPa or less and an elastic modulus at 250 ° C. of 12 MPa or less.
When the elastic modulus at a high temperature of the cured product is low, the thermal stress is reduced, cracks are difficult to occur in a high temperature environment, and the environment in which electric and electronic parts can be used becomes wide.
In addition, the measuring method of the elasticity modulus at the time of high temperature is described in the item of an Example.

5. Use of Epoxy Resin, Composition, and Cured Product of the Present Invention The biphenyl epoxy resin of the present invention has a small amount of hydrolyzable chlorine, is excellent in electrical reliability, has a high crystallization rate, and has good productivity.
The curable epoxy resin composition of the present invention containing this biphenyl-based epoxy resin is excellent in curability, insulation reliability, hygroscopicity, heat resistance and the like.

Therefore, the epoxy resin and the curable epoxy resin composition of the present invention can be suitably used for any application as long as the above characteristics are required.
Applications that can make use of such features include, for example, paint fields such as electrodeposition paints for automobiles, heavy-duty anticorrosion paints for ships and bridges, paints for the inner surface of beverage cans; laminates, semiconductor encapsulants, Electrical and electronic fields such as insulating powder coatings, coil-impregnated insulating coatings, and coil-impregnated insulating coatings; seismic reinforcement of bridges, concrete reinforcement, flooring of buildings, linings of water supply facilities, drainage and permeable pavement, for vehicles and aircraft Examples include civil engineering / architecture / adhesive fields such as adhesives.

Among these, the epoxy resin of the present invention and the composition or cured product obtained by using the epoxy resin are particularly useful for electrical / electronic applications such as semiconductor encapsulants and laminated circuit boards.
In addition, when applying the curable epoxy resin composition of this invention for the said use, it may be used as a hardened | cured material after hardening a composition, and may be hardened in the middle of the manufacturing process of the said product. .

EXAMPLES Hereinafter, although this invention is demonstrated further in detail using an Example, this invention is not limited by a following example, unless the summary is exceeded.
In addition, the value of various manufacturing conditions and evaluation results in the following examples also 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.

1. Raw materials (1) Chemicals The chemicals used in this example are as follows.
4-phenylphenol: manufactured by Tokyo Chemical Industry Co., Ltd., reagent grade 1 epichlorohydrin: manufactured by Kashima Chemical Co., Ltd. 2-propanol: manufactured by Wako Pure Chemical Industries, Ltd., reagent special grade methanol: manufactured by Wako Pure Chemical Industries, Ltd. Reagent special grade sodium hydroxide: Wako Pure Chemical Industries, Ltd., reagent special grade methyl isobutyl ketone: Wako Pure Chemical Industries, reagent special grade

(2) Auxiliaries The curing agent and curing accelerator used in the curing test of the resin composition are as follows.

Epoxy resin 3 (polyfunctional epoxy resin): Orthocresol novolak type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name: EOCN-1020-65 (epoxy equivalent: 199 g / equivalent))
Multifunctional curing agent 1 (phenolic): phenol novolac resin (manufactured by Gunei Chemical Co., Ltd., trade name: PSM4261 (hydroxyl equivalent: 103 g / equivalent))
Curing accelerator 1: Triphenylphosphine (trade name, triphenylphosphine, manufactured by Tokyo Chemical Industry Co., Ltd.)
Multifunctional curing agent 2 (anhydride-based): glycerin bisanhydro trimellitate monoacetate (trade name: TMTA-C (acid anhydride equivalent: 182 g / equivalent) manufactured by Shin Nippon Rika Co., Ltd.)
Curing accelerator 2: 2-ethyl-4 (5) -methylimidazole (Mitsubishi Chemical Corporation, trade name: EMI-24)

2. Analysis / Evaluation Method The measurement / evaluation method of epoxy equivalent, hydrolyzable chlorine content, melting point, and crystallization rate in this example is described in [Detailed Description of the Invention] in [Description of Embodiments]. The description is as described in (2) to (5) of “1. Biphenyl type epoxy resin”.

3. Synthesis of Epoxy Resin (1) Synthesis of Epoxy Resin for Examples and Comparative Examples [Synthesis Example 1] (Biphenyl epoxy resin of the present invention: Epoxy resin 1)
A 2-L four-neck flask equipped with a thermometer, a stirrer, and a cooling tube was charged with 90 g of 4-phenylphenol, 319 g of epichlorohydrin, 124 g of 2-propanol, and 44 g of water, and heated to 40 ° C. to be uniformly dissolved. .

Subsequently, 51 g of an aqueous sodium hydroxide solution (concentration: 48.5% by weight) was added dropwise while raising the temperature to 65 ° C. over 90 minutes. After completion of the dropwise addition, the reaction was completed by maintaining at 65 ° C. for 30 minutes.
After adding 96 g of water, the reaction solution was transferred to a 3 L separatory funnel and kept at 65 ° C. for 1 hour to separate into an oil layer and an aqueous layer. The aqueous layer was extracted from here to remove by-product salts and excess sodium hydroxide.

Subsequently, excess epichlorohydrin and 2-propanol were distilled off from the oil layer under reduced pressure to obtain a crude epoxy resin.
This crude epoxy resin was transferred to a four-necked flask similar to the above and dissolved in 180 g of methyl isobutyl ketone (hereinafter sometimes abbreviated as “MIBK”), and 2.5 g of 48.5 wt% sodium hydroxide aqueous solution was added. And reacted again at a temperature of 65 ° C. for 1 hour.

Thereafter, 100 g of MIBK was added, followed by washing with 500 g of water four times, and then MIBK was distilled off under reduced pressure at 150 ° C. to obtain a crude epoxy resin.
60 g of the crude epoxy resin obtained above was weighed and charged into a 200 ml four-necked flask, added with 40 g of MIBK, and heated and dissolved at 70 ° C. using an oil bath in a nitrogen atmosphere. After the epoxy resin was sufficiently dissolved, the crystals obtained by cooling to 25 ° C. were filtered and washed with a small amount of MIBK.

50 g of washed crystals were again charged into the four-necked flask, 20 g of new MIBK was added, and the mixture was heated to 70 ° C. and dissolved. After the epoxy resin was sufficiently dissolved, the crystal formed by cooling to 25 ° C. was filtered off and washed with a small amount of MIBK.
Using 40 g of the obtained crystals, the procedure of “70 ° C. temperature rise-dissolution−25 ° C. cooling / crystallization-filtration-washing” is repeated again to obtain a purified epoxy resin (“epoxy resin 1”). Obtained.

[Synthesis Example 2] (Biphenyl epoxy resin outside the scope of the present invention)
An epoxy resin was synthesized according to Synthesis Example 2 described in a publicly known document (WO2010 / 137501).
Specifically, 181 g of 4-phenylphenol (manufactured by Tokyo Kasei Kogyo Co., Ltd.), 394 g of epichlorohydrin, and 80 g of methanol are charged into a 2 L four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and heated to 70 ° C. After the temperature was raised and dissolved uniformly, 44 g of flaky sodium hydroxide was added in portions over 90 minutes.

After completion of the addition, the reaction is completed by maintaining at 70 ° C. for 60 minutes. After adding 200 g of water, the reaction solution is transferred to a 3 L separatory funnel and left to stand at 65 ° C. for 1 hour, and then separated oil and water layers The aqueous layer was extracted from the product to remove by-product salt and excess sodium hydroxide. This washing operation was performed twice.
Subsequently, excess epichlorohydrin and methanol were distilled off from the product under reduced pressure to obtain a crude epoxy resin.

This crude epoxy resin was dissolved in 480 g of MIBK, and the temperature was raised to 70 ° C., then 12 g of a 10 wt% sodium hydroxide aqueous solution was added, and a further reaction was performed at a temperature of 70 ° C. for 1 hour.
Water washing was performed using 500 g of water until the washing water became neutral, and then MIBK was completely removed under reduced pressure at 150 ° C. to obtain an epoxy resin (“epoxy resin 2”).
The epoxy equivalents, hydrolyzable chlorine content, melting point, and crystallization rate of the epoxy resins 1 and 2 obtained above were measured by the methods described above. The results are shown in Table 1.

4). Production and Evaluation of Curable Epoxy Resin Composition [Example 1 and Comparative Examples 1 and 2]
(1) Production of curable epoxy resin composition Predetermined epoxy resin and curing agent were blended in the ratio shown in Table 2, heated to 100 ° C, and stirred until uniform. Then, it cooled to 80 degreeC, the hardening accelerator was added in the ratio shown in Table 2, and it stirred until it became uniform, and prepared the curable epoxy resin composition.
In Table 2, a blank in the table indicates that the resin or the like was not used (that is, the addition amount is zero), and “-” indicates that there is no data.

(2) Creation and evaluation of hardened | cured material About the curable epoxy resin composition obtained above, the curability and physical property were evaluated as follows. The results are summarized in Table 2.

<Curing property>
A casting plate was prepared by using two glass plates each having a release film (PET) laminated on one surface, with the release film side facing inward, and adjusting the distance between the glass plates to 5 mm.
On this casting plate, 50 g of the curable epoxy resin composition was cast at 80 ° C. and held in an oven under the conditions of 120 ° C. × 2 hours + 175 ° C. × 6 hours. After the predetermined time had elapsed, heating was stopped, and the mold was taken out from the casting plate after being held in the oven and allowed to cool to room temperature.
The obtained molded body was heated to 175 ° C., and the one not melted was evaluated as curability “◯”, and the melted one was evaluated as curability “x”.
The following evaluation was further carried out on the cured product. The results are shown in Tables 2 and 3.

<Chlorine content of extracted water: insulation reliability>
The cured product obtained above was pulverized with a wonder blender (manufactured by Osaka Chemical Co., Ltd.), and a pulverized cured product was created through a 20-mesh wire mesh.
20 g of this cured product was weighed into a polyethylene bottle, 80 mL of ultrapure water was added, and the mixture was sealed and heated in a dryer at 95 ° C. After heating for 20 hours, the mixture was cooled to room temperature, and the contents were filtered through filter paper 5A to obtain extracted water.
1 g of the obtained extracted water was put into a beaker, 100 mL of acetone and 25 mL of acetic acid were added, and the amount of chlorine was measured by potentiometric titration using a silver nitrate solution having a concentration of 0.002 mol / L. The obtained results are shown in Table 3.

<Hygroscopic rate: hygroscopicity>
The obtained cured product was cut into a size of “length 3 cm × width 3 cm × thickness 5 mm” to prepare a test piece, which was placed in a constant temperature and humidity chamber adjusted to 85 ° C. and 85% RH. The rate of change in weight after the passage of 168 hours was taken as the moisture absorption rate.

<Heat modulus (measurement of 200 ° C. (E ′): heat resistance)>
The cured product is cut to a size of “5 cm long × 1 cm wide × 5 mm thick” to create a test piece, which is analyzed in a three-point bending mode with a thermomechanical analyzer (DMS: EXSTAR6100 manufactured by Seiko Instruments Inc.). 1 Hz of 200 ° C. (E ′) was defined as the elastic modulus at high temperature (thermal elastic modulus). The temperature rise pattern was measured at an initial temperature of 30 ° C., an ultimate temperature of 280 ° C., and a rate of temperature rise of 5 ° C./min.

4). Evaluation of Results From Table 1, the epoxy resin 1 of Synthesis Example 1 whose epoxy equivalent, hydrolyzable chlorine, and melting point are within the specified range of the present invention is produced at a higher crystallization rate than the epoxy resin 3 of Synthesis Example 2. Excellent insulation and excellent insulation reliability due to low hydrolyzable chlorine content.
The epoxy resin hardened | cured material of Example 1 using the epoxy resin (epoxy resin 1 of the synthesis example 1) of this invention whose epoxy equivalent, hydrolysable chlorine, and melting | fusing point are in the prescription | regulation range of this invention from Table 2 is a comparative example. It turns out that it is excellent in the amount of chlorine of extraction water, hygroscopicity, and a 200 degreeC elasticity modulus with respect to the epoxy resin cured material of 1 and 2.

  In addition, even if the epoxy resin within the scope of the present invention is used as in Reference Example 1, when a phenol-based polyfunctional curing agent is used instead of a polyfunctional acid anhydride curing agent, the curability is poor. It has become.

  The curable epoxy resin composition obtained by the present invention has good curability, and the cured product obtained by using the epoxy resin composition has excellent curability, insulation reliability, and hygroscopicity. Can be suitably used.

Claims (6)

An epoxy resin containing a structural unit derived from an epoxy compound represented by the following formula (1) and having an epoxy equivalent of 223 to 241 g / eq (hereinafter referred to as “biphenyl epoxy resin”), and a polyfunctional acid anhydride curing agent A curable epoxy resin composition comprising:

  2. The curable epoxy resin composition according to claim 1, wherein the biphenyl-based epoxy resin has a hydrolyzable chlorine content of 1000 ppm or less.   The curable epoxy resin composition according to claim 1 or 2, wherein the biphenyl epoxy resin has a melting point of 73 to 76 ° C.   The content of the polyfunctional acid anhydride curing agent is 0.01 to 100 parts by weight per 100 parts by weight of the epoxy resin, and the curable epoxy resin composition according to any one of claims 1 to 3. .   Hardened | cured material formed by hardening | curing the epoxy resin composition of any one of Claims 1-4.   An electric / electronic component comprising the cured product according to claim 5.