JP2017149801A - Epoxy resin, curable epoxy resin composition based on the resin, cured product, and electric/electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin which has a low hydrolyzable chlorine content and is excellent in insulation reliability, has a high crystallization speed, and is excellent in productivity; a curable epoxy resin composition based on the epoxy resin which is excellent in curability, insulation reliability, hygroscopicity and heat resistance; and a cured product of the same.SOLUTION: There is provided an epoxy resin which is an epoxy resin containing 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/eg; and a curable epoxy resin composition containing 0.01-1,000 pts.wt. of a polyfunctional epoxy resin per 100 pts.wt. of the epoxy resin.SELECTED DRAWING: None

Description

The present invention provides an epoxy resin with low hydrolyzable chlorine content, excellent insulation reliability, high crystallization speed and excellent productivity, and curability, insulation reliability, hygroscopicity, and heat resistance including this epoxy resin. The present invention relates to an excellent curable epoxy resin composition and a cured product obtained therefrom.
The present invention also relates to an electric / electronic component comprising the curable epoxy resin composition.

  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

The first object of the present invention is to provide an epoxy resin having a low hydrolyzable chlorine content and a high crystallization rate. Epoxy resins having such characteristics are excellent in electrical characteristics and productivity.
Moreover, the 2nd subject of this invention is provision of the curable epoxy resin composition excellent in sclerosis | hardenability, insulation reliability, heat resistance, and hygroscopic property, and its hardened | cured material. 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-mentioned problems, the present inventor has obtained an epoxy resin containing a structural unit derived from glycidyl ether of 4-phenylphenol whose epoxy equivalent, hydrolyzable chlorine amount, and melting point are controlled within a specific range. And the crosslinkable curable epoxy resin composition containing this resin and a polyfunctional epoxy resin discovered that the said subject could be solved, and completed this invention.
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) having an epoxy equivalent of 223 to 241 g / eq (hereinafter referred to as “biphenyl type”) "Epoxy resin").

[2] The biphenyl epoxy resin as described in [1] above, wherein hydrolyzable chlorine is 1000 ppm or less.
[3] The biphenyl epoxy resin as described in [1] or [2] above, having a melting point of 73 to 76 ° C.
[4] Curability comprising the biphenyl epoxy resin according to any one of the above [1] to [3] and 0.01 to 1000 parts by weight of a polyfunctional epoxy resin per 100 parts by weight of the epoxy resin. Epoxy resin composition.
[5] Further, as the curing agent, at least one curing agent selected from the group consisting of a phenolic curing agent, an amine curing agent, a monofunctional acid anhydride curing agent, and an amide curing agent is used. The curable epoxy resin composition according to claim 4, containing 0.1 to 1000 parts by weight per 100 parts by weight of the epoxy resin.
[6] A cured product obtained by curing the curable epoxy resin composition according to [4] or [5].
[7] An electric / electronic component comprising the cured product according to [6].

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 configuration requirements of the present invention will be described individually.
1. Epoxy resin (1) Features The epoxy resin of the present invention is an epoxy resin (biphenyl type epoxy resin) containing a structural unit derived from an epoxy compound represented by the following formula (1) having a specific epoxy equivalent, and is hydrolyzed. The amount of reactive chlorine is low, the insulation reliability is excellent, the crystallization speed is fast, 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-based epoxy resin of the present invention is required to be 223 to 241 g / eq (“eq” means “equivalent”). By making the epoxy equivalent within this range, the effect of the present invention is achieved. A sufficiently fast crystallization rate 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 a rate of 1 ° C./min using a differential scanning calorimeter (DSC: for example, EXSTAR 7020 manufactured by Seiko Instruments Inc.). It is.

(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. Epoxy resin production method The epoxy equivalent, hydrolyzable chlorine amount, and melting point satisfy the above-mentioned conditions. The production method of the biphenyl epoxy resin of the present invention will be described below. Is not limited to the following production method as long as the epoxy resin satisfies the above conditions.
The following description is for illustrating a more efficient method for producing a biphenyl epoxy resin. Examples of such a method include a one-step production method and a method via 4-phenylphenol represented by the following formula (2) (hereinafter sometimes referred to as “4PP”).

(1) Manufacture of biphenyl-type epoxy resin About the manufacturing method of the biphenyl-type epoxy resin of this invention with which an epoxy equivalent, the amount of hydrolyzable chlorine, and melting | fusing point satisfy | fill the above-mentioned suitable range, the epoxy resin which satisfy | fills the conditions prescribed | regulated in this application is obtained. As long as it can be used, the method is not particularly limited, and 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 addition, when manufacturing the epoxy resin by the said method, you may use together other polyvalent hydroxy compounds as a raw material other than 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, it is preferable that the amount of epihalohydrin is 20 equivalents or less because production efficiency tends to be improved.

In addition, as epihalohydrin in this reaction, epichlorohydrin or epibromohydrin is usually used.
Next, while stirring the 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 an unreacted hydroxyl group and the generated epoxy resin hardly react and the high molecular weight reaction can be 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 mentioned.

  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 less because side reactions can be suppressed, and particularly halogens derived from epihalohydrin and halogen-containing compounds (hereinafter collectively referred to as “chlorine impurities”) can be 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, 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 conducting an allylation reaction on 4PP, which is a phenolic compound, to introduce an allyl group, and then further 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 generated by the reaction of unreacted raw material compounds and epihalohydrins such as epichlorohydrin. . By reacting such chlorine-based impurities with a strong alkali, the contained chlorine is converted into an inorganic chlorine-based water-soluble compound and washed with water to obtain a purified epoxy resin.

  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 alone or as a mixed solvent.

  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 reactivity 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, a mild and controllable reaction can proceed.
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) Characteristics of curable epoxy resin composition The curable epoxy resin composition of the present invention comprises at least 100 parts by weight of the biphenyl epoxy resin of the present invention described above and a polyfunctional epoxy resin. A curable epoxy resin composition containing 01 to 1000 parts by weight.

The curable epoxy resin composition of the present invention uses the biphenyl epoxy resin of the present invention, a phenolic curing agent, an amine curing agent, a monofunctional acid anhydride curing agent as a polyfunctional epoxy resin and a curing agent, and A curable epoxy resin composition can be obtained by combining an amide-based curing agent or the like.
In addition to the above, a composition in which the epoxy resin of the present invention is further made into a copolymer with another component having an epoxy group and is itself a polyfunctional epoxy resin, combined with a polyfunctional and / or monofunctional curing agent. This corresponds to the curable epoxy resin composition of the present application.

Of course, in addition to the above components, the curable epoxy resin composition of the present invention may include other epoxy resins other than the biphenyl-based epoxy resin of the present invention (hereinafter simply referred to as “other epoxy resins”) as necessary. A curing accelerator, an inorganic filler, a coupling agent, and the like can be appropriately blended as long as they do not impair the gist and effect of the present invention.
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, the essential components and optional components constituting the composition will be individually described.

(2) Curing Agent In the present invention, the curing agent refers to a substance that contributes to a crosslinking reaction and / or chain extension reaction between epoxy groups of an epoxy resin. In addition, even if what is usually called “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” in the present invention. To do.

In the curable epoxy resin composition of the present invention, the content of the 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 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, when the curing agent is used in such a large amount that the content exceeds 1000 parts by weight, not only the curing reaction of the epoxy resin becomes very fast, the molded product becomes non-uniform, but also easily becomes distorted, A large amount of a curing agent that does not contribute to the curing reaction may remain 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 preferable curing agent is 500 parts by weight, and more preferably 300 parts by weight. When used in such an amount, low molecular components contained as impurities in the curing agent can be prevented from bleeding from the cured product.
Moreover, 0.5 weight part is preferable and, as for the minimum of content of a hardening | curing agent, 1 weight part is more preferable. By setting it as such quantity, desired hardness can be obtained more rapidly.

In the above, “solid content” means a component excluding the 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 epoxy resin, and when biphenyl epoxy resin and other epoxy resins are included, it corresponds to the total amount of biphenyl epoxy resin and other epoxy resins.
There is no restriction | limiting in particular as a hardening | curing agent, Generally all known as a hardening | curing agent for epoxy resins can be used. For example, phenolic curing agents, aliphatic amines, polyetheramines, alicyclic amines, aromatic amines and other amine curing agents, monofunctional acid anhydride curing agents, amide curing agents, tertiary amines And imidazoles.

Among the above curing agents, by including a phenolic curing agent, the curable epoxy resin composition of the present invention can obtain excellent heat resistance, stress resistance, hygroscopicity, flame retardancy, etc. The agent preferably contains a phenolic curing agent. Further, from the viewpoint of heat resistance and the like, it is preferable to include a monofunctional acid anhydride curing agent and an amide curing agent. It is also preferable to use imidazoles from the viewpoint of sufficiently proceeding the curing reaction and improving heat resistance.
A hardening | curing agent may be used individually by 1 type, and may be used in combination of 2 or more type. When two or more kinds of curing agents are used in combination, they may be used after mixing them in advance to prepare a mixed curing agent, or when mixing each component of the curable epoxy resin composition, The components may be added individually and mixed simultaneously.

<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 viewpoint of heat resistance after curing of the composition, curability, etc., as the phenolic curing agent, a phenol novolak resin (for example, a compound represented by the following formula (3)), a phenol aralkyl resin (for example, the following formula: (Compound represented by (4)), biphenyl aralkyl resin (for example, a compound represented by the following formula (5)), naphthol novolak resin (for example, a compound represented by the following formula (6)), naphthol aralkyl resin (for example, the following A compound represented by the formula (7)), a trisphenolmethane type resin (for example, a compound represented by the following formula (8)), a phenol / benzaldehyde / xylylene methoxide polycondensate (for example, represented by 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, it is preferable to use, for example, a compound represented by the following formula (10), particularly a phenol novolak resin (for example, the following formula (3)), a phenol aralkyl resin (for example, the following formula (4)), 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 curing agents include curing agents other than tertiary amines, such as aliphatic amines, polyether amines, alicyclic amines, aromatic amines, and the like, and third (other than these curing agents). Secondary 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 Examples thereof include dimethyldiphenylmethane and α, α′-bis (4-aminophenyl) -p-diisopropylbenzene.

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.
The tertiary amine, unlike the primary amine and secondary amine, has a low reactivity with an epoxy group because it does not have active hydrogen in the molecule, but a curing reaction catalyst as a curing accelerator. It has a feature that it has an action and may contribute to curing thereafter.

  Examples of such tertiary amines include 1,8-diazabicyclo (5,4,0) undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol. These tertiary amines may be used alone, or two or more thereof may be used in any combination and mixing ratio.

The amine-based curing agent (including a tertiary amine) is an equivalent ratio of functional groups in the curing agent to epoxy groups in all epoxy resin components contained in the curable epoxy resin composition (hereinafter referred to as “equivalent compounding ratio”). It is preferable to use it 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.
Moreover, in order to make the physical property of hardened | cured material more excellent, it is more preferable that the said equivalent compounding ratio shall be 0.9-1.1. It is preferable to set the equivalent compounding ratio within this range because unreacted epoxy groups and curing agents are less likely to remain.

In addition, an equivalent compounding ratio is a value defined by the following formula.
Equivalent compounding ratio = (amount of curing agent (g) / equivalent of curing agent (g / eq)) / (epoxy resin amount (g)
/ Epoxy equivalent of epoxy resin (g / eq))
(However, “equivalent of curing agent” is the mass of the curing agent capable of reacting with one equivalent of epoxy group.)

<Monofunctional type anhydride anhydride curing agent>
Examples of the monofunctional acid anhydride curing agent that can be used in the present invention include monofunctional acid anhydrides and modified products thereof, among which monofunctional acid anhydride curing agents are preferable.
By using a monofunctional acid anhydride curing agent, good curing reaction controllability can be maintained in a curing system having a biphenyl epoxy resin and a polyfunctional epoxy resin preferably used in the present invention.

  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, Methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methyl hymic acid anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid anhydride, het acid anhydride, nadic An acid 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. 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. 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 monofunctional acid anhydride curing agents mentioned above may be used alone or in combination of two or more in any combination and blending amount.
When the above 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 in the range of 0.8 to 1.5. It is preferable to use as described above. Within this range, unreacted epoxy groups and functional groups of the curing agent are less likely to remain, which is preferable.

<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.
When using an amide curing agent, the amide curing agent should be used in an amount of 0.1 to 20% by weight based on the total amount of all epoxy resin components and the amide curing agent in the curable epoxy resin composition. Is preferred.

<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.
When using imidazole, it is preferable to use it so that imidazole may be 0.1 to 20 weight% with respect to the sum total of all the epoxy resin components and imidazoles in a curable epoxy resin composition.

<Other curing agents>
In the curable epoxy resin composition of the present invention, other curing agents can be used in addition to the curing agent. As other curing agents, those generally known as epoxy resin curing agents can be used without particular limitation as long as they do not impair the objects and effects of the present invention. These other curing agents may be used alone or in combination of two or more.

(3) Polyfunctional epoxy resin and other epoxy resins In the curable epoxy resin composition of the present invention, a polyfunctional epoxy resin is used in addition to the biphenyl epoxy resin.
As such a polyfunctional epoxy resin, an epoxy resin having two or more epoxy groups in one molecule can be used without particular limitation.

  Specifically, in the epoxy resin exemplified below, one having two or more epoxy groups in one molecule as described above is 0.01 to 1000 weights per 100 parts by weight of the biphenyl epoxy resin. Use the part. If the amount used is less than 0.01 parts by weight, it may take excessive time to cure the curable epoxy resin composition, or the cured product may not have sufficient hardness. On the other hand, if such an epoxy resin is used in excess of 1000 parts by weight, the curing reaction may become excessively fast, or good reliability and excellent crystallization performance based on the biphenyl-based epoxy resin may not be obtained sufficiently. .

The preferred content of the polyfunctional epoxy resin is 1 part by weight or more per 100 parts by weight of the biphenyl epoxy resin, more preferably 10 parts by weight or more, and further preferably 30 parts by weight or more. The content is preferably 500 parts by weight or less, more preferably 300 parts by weight or less, and still more preferably 100 parts by weight or less.
By containing the polyfunctional epoxy resin in such a range, good curing reactivity and the above-mentioned properties of the biphenyl epoxy resin can be exhibited in an excellent balance.

The polyfunctional epoxy resin is not particularly limited as long as it is an epoxy resin other than the biphenyl-based epoxy resin and has two or more epoxy groups per molecule, as long as the effects and purposes of the present invention are not impaired.
As such an epoxy resin, the polyfunctional thing can be mentioned among the epoxy resins illustrated below.

Moreover, in this invention, as long as said conditions are satisfy | filled, in addition to these biphenyl type epoxy resins and polyfunctional epoxy resins, the epoxy resin which does not correspond to these resins can be used. By including such an epoxy resin, the heat resistance, stress resistance, moisture absorption resistance, flame retardancy and the like of the curable epoxy resin composition of the present invention can be improved.
The said polyfunctional epoxy resin and other epoxy resin which can be used for the curable epoxy resin composition of this invention say the epoxy resin which does not correspond to the said biphenyl type epoxy resin.
Specific examples include 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 resorcin 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, dihydroxy diphenyl ether type epoxy resin, thiodiphenols -Derived epoxy resins, dihydroxynaphthalene-type epoxy resins, dihydroxyanthracene-type epoxy resins, dihydroxydihydroanthracene-type epoxy resins, dicyclopentadiene-type epoxy resins, epoxy resins derived from dihydroxystilbenes, phenol novolac-type epoxy resins, cresols Novolac epoxy resin, bisphenol A novolak epoxy resin, naphthol novolac epoxy resin, phenol aralkyl epoxy resin, naphthol aralkyl epoxy resin, biphenyl aralkyl epoxy resin, terpene phenol epoxy resin, dicyclopentadiene phenol epoxy resin, Epoxy resin derived from the condensation product of phenol and hydroxybenzaldehyde, phenol Epoxy resin derived from condensate of rotonaldehyde, epoxy resin derived from condensate of phenol and glyoxal, epoxy resin derived from co-condensation resin of heavy oil or pitch with phenols and formaldehyde, diamino Examples include epoxy resins derived from diphenylmethane, 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 an epoxy resin that does not correspond to the biphenyl epoxy resin and the polyfunctional epoxy resin, the content is 100% by weight of the total epoxy resin component in the composition. 0.01 to 99.9 parts by weight thereof is preferable, more preferably 25 to 90% by weight, and 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 and organic borons, addition compounds of organic phosphines and 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, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3- Examples include quinone compounds such as dimethoxy-1,4-benzoquinone and phenyl-1,4-benzoquinone, diazophenylmethane, and the like.

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.
When the content of the curing accelerator is not less than the above lower limit value, a good curing acceleration effect can be obtained, and when it is not more than the above upper limit value, desired cured 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 a range that does not impair the gist and effect of the present invention. . 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 a phenolic curing agent 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 has low 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. 1-methoxy-2-propanol (methoxypropanol): manufactured by Tokyo Chemical Industry Co., Ltd., reagent)
2-Propanol: manufactured by Wako Pure Chemical Industries, reagent special grade methanol: manufactured by Wako Pure Chemical Industries, reagent special grade sodium hydroxide: manufactured by Wako Pure Chemical Industries, reagent special grade methyl isobutyl ketone: Wako Pure Chemical Made by Kogyo Co., Ltd., reagent grade

(2) Auxiliaries The curing agent and curing accelerator used in the curing test of the resin composition are as follows.
Epoxy resin X (polyfunctional epoxy resin): Orthocresol novolak type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name: EOCN-1020-65 (epoxy equivalent: 199 g / equivalent))
Curing agent 1: 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.)
Curing agent 2: Glycerin bisanhydro trimellitate monoacetate (New Nippon Rika (
Co., Ltd., trade name TMTA-C (acid anhydride equivalent: 182 g / equivalent))
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. Epoxy resin”.

3. Synthesis of Epoxy Resin (1) Synthesis of Epoxy Resin for Examples and Comparative Examples [Examples 1 and 2] (Preparation of biphenyl type epoxy resins A and B of the present invention)
4-phenylphenol 90 g, epichlorohydrin 688 g, methoxypropanol 268 g, and water 96 g were charged into a 2 L four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and heated to 40 ° C. and uniformly dissolved.

Subsequently, while raising the temperature to 65 ° C. over 90 minutes, an aqueous sodium hydroxide solution (concentration: 48.
51 g) was added dropwise. After completion of the dropwise addition, the reaction was completed by maintaining at 65 ° C. for 30 minutes.
After adding 44 g of water, the reaction solution was transferred to a 3 L separatory funnel, and kept at a temperature of 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.

Next, excess epichlorohydrin and methoxypropanol 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 an epoxy resin A.
60 g of the epoxy resin A 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 the obtained crystals 40 g, the procedure of “70 ° C. temperature rise-dissolution−25 ° C. cooling / crystallization-filtration-washing” was repeated again to obtain a purified epoxy resin (“epoxy resin B”). .
[Example 3] (Preparation of biphenyl epoxy resin C of the present invention)
The reaction was carried out in the same manner as in Example 1 except that the amount of epichlorohydrin charged was 319 g, the amount of water used was 44 g, and 124 g of 2-propanol was used instead of methoxypropanol.

After completion of the reaction, 96 g of water was added, and the reaction solution was transferred to a 3 L separatory funnel. Then, separation and washing were performed in the same manner as in Example 1 above, and excess epichlorohydrin and 2- Propanol was distilled off to obtain a crude epoxy resin.
The crude epoxy resin was subjected to additional reaction in the same manner as in Example 1, washed with water, heated to 150 ° C., and the solvent MIBK was distilled off under reduced pressure to obtain an epoxy resin (“epoxy resin C”). Obtained.

[Example 4] (Preparation of biphenyl type epoxy resin D of the present invention)
In Example 3 above, the reaction, separation and washing were carried out in the same manner except that the amount of epichlorohydrin charged was 147 g, the amount of 2-propanol used was 57 g, and the amount of water used was 20 g. Excess epichlorohydrin and 2-propanol were distilled off to obtain a crude epoxy resin.
The crude epoxy resin was subjected to additional reaction, water washing, and vacuum distillation of the solvent at 150 ° C. in the same manner as in Example 3 to obtain an epoxy resin (“epoxy resin D”).

[Comparative Example 1] (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 E”).
The epoxy equivalents, hydrolyzable chlorine content, melting point, and crystallization rate of the epoxy resins obtained in Examples 1 to 3 and Comparative Example 1 were measured by the methods described above. The results are shown in Table 1.

4). Production and Evaluation of Curable Epoxy Resin Composition [Examples 5 to 11 and Comparative Examples 2 to 4, Reference Example 1]
(1) Production of curable epoxy resin composition The epoxy resin and the curing agent were blended in the ratios shown in Tables 2 and 3, 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 Tables 2 and 3, “parts” represents “parts by weight”, the blanks in the tables indicate that the resin or the like was not used (that is, the addition amount was zero), and “−” Each indicates 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 Tables 2 and 3.

<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 this casting plate was 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 removed from the casting plate after being kept in the oven until it reached room temperature.
The obtained molded body was again heated to 175 ° C., and the one that was not melted was evaluated as curability “◯”, and the melted one was evaluated as curability “x”.

  The following evaluation was further carried out for the cured product having a curability of “◯”. 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.

<Elastic modulus at high temperature (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.). The elastic modulus at high temperature was set to 200 ° C. (E ′) of 1 Hz. 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 equivalents of the present invention, the amount of hydrolyzable chlorine, and the melting point of the epoxy resin of Examples 1 to 4 within the specified range of the present invention are compared to the epoxy resin of Comparative Example 1. It can be seen that the hydrolyzable chlorine amount is excellent and the crystallization rate is high.
The hardened | cured material based on the curable epoxy resin composition of Examples 5-11 using the epoxy resin of this invention from Table 2, Table 3 becomes the epoxy resin hardened | cured material of the comparative example 2 and 3 outside the scope of the present invention. In comparison, the amount of chlorine in the extracted water and the moisture absorption rate are small, the insulation reliability when molded is excellent, and the elastic modulus during heating is also high. Note that Comparative Example 3 is a cured product using only a bifunctional epoxy resin (epoxy resin 1), and has a high thermal elastic modulus due to progress of crosslinking, but is considered to be weak in strength. . There is also a large amount of chlorine in the extracted water.

  In addition, although the reference example 1 used the epoxy resin of this invention, when it was set as a composition, it was the example made outside the scope of the present invention. This is because the polyfunctional epoxy resin (epoxy resin 1) is not included, or the curability is poor. If this is contrasted with Examples 7 to 10 in Table 2, the characteristics and effects of the cured product based on the curable epoxy resin composition of the present application are clear.

  The epoxy resin obtained according to the present invention has a low hydrolyzable chlorine content and a high crystallization rate, and thus has excellent electrical characteristics and productivity, and a curable epoxy resin composition obtained by using the epoxy resin composition and the curable epoxy resin composition. The cured product obtained from the composition is excellent in curability, insulation reliability, heat resistance, and hygroscopicity, and can be suitably used for electric / electronic parts.

Claims (7)

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”) ).

  2. The biphenyl epoxy resin according to claim 1, wherein the hydrolyzable chlorine is 1000 ppm or less.   Melting | fusing point is 73-76 degreeC, The biphenyl type epoxy resin of Claim 1 or 2 characterized by the above-mentioned.   A curable epoxy resin composition comprising the biphenyl epoxy resin according to any one of claims 1 to 3 and 0.01 to 1000 parts by weight of a polyfunctional epoxy resin per 100 parts by weight of the epoxy resin. .   Further, as the curing agent, at least one curing agent selected from the group consisting of a phenolic curing agent, an amine curing agent, a monofunctional acid anhydride curing agent, and an amide curing agent is used as the biphenyl epoxy resin 100. It contains 0.1-1000 weight part per weight part, The curable epoxy resin composition of Claim 4 characterized by the above-mentioned.   Hardened | cured material formed by hardening | curing the curable epoxy resin composition of Claim 4 or 5.   An electric / electronic component comprising the cured product according to claim 6.