JP2002030122A - Epoxy resin modifier, epoxy resin composition, and circuit substrate and ic sealing agent therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin modifier which has a low viscosity and an excellent dissolution dispersibility; an epoxy resin composition which can be cured to have excellent mechanical strengths; and a circuit substrate and a sealing agent therewith. SOLUTION: The modifier comprises a graft polymer produced by graft polymerizing 30-80% by weight of a monomer compound (a2) selected from the group consisting of vinyl compounds in the presence of 20-70% by weight of a rubber polymer (a1), wherein 20% by weight of the graft polymer, if added in 80% by weight of methyl ethyl ketone, has an average particle size of 50 nm-600 nm determined by a dynamic light scattering method and a solution viscosity of 500 mPa.S or less. The epoxy resin composition comprises 1-100 parts of the graft polymer contained in the modifier and 100 parts of an epoxy resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin modifier and an epoxy resin composition, and a circuit board and an IC encapsulant formed using the same. Epoxy resin composition having low stress (low elastic modulus) and excellent fracture toughness, and a circuit board and I formed using the same
C sealing material.

[0002]

2. Description of the Related Art It has been known that a cured product of an epoxy resin has excellent physical and chemical properties. For example, since it is excellent in heat resistance, corrosion resistance, electrical characteristics, and chemical resistance, it is used in a wide range of fields such as adhesives, paints, sealing materials, sealing materials, and laminates. However, a cured product of an epoxy resin has these excellent properties, but has a weak point of being brittle. There is a strong demand in the epoxy resin industry to compensate for this brittleness and to obtain a product having high impact resistance and flexibility. To solve this problem, Japanese Patent Publication No. 55-33732.
As disclosed in Japanese Patent Application Publication No. 57-30133, a modified acrylonitrile-butadiene copolymer (modified NBR) into which various functional groups such as a carboxyl group which can be expected to react with an epoxy resin or a curing agent is introduced. Used as an epoxy resin modifier. In some applications, silicone oil modified with a functional group is also used. However, since the polymers used as these modifiers are all uncrosslinked polymers, depending on the type and curing conditions of the curing agent, the particle size of the polymer dispersed in the epoxy resin composition and the The distribution changes,
Since the dispersion state of the polymer in the epoxy resin is different, there is a disadvantage that the characteristics of the cured product of the epoxy resin change. Further, in recent years, the interlayer insulating adhesive for a multilayer printed wiring board or the like may be applied thinly, and a solvent may be used. In this case, the modifier must also be dispersed in the solvent. However, the polymer dispersed in the solvent is an uncrosslinked polymer, and the properties of the cured product change for the above-mentioned reason, and there is a problem that stable physical properties are not exhibited.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and solves the above-mentioned problems. It is an object of the present invention to provide an epoxy resin composition excellent in elastic modulus and fracture toughness, and a circuit board and an IC sealing material formed using the same.

[0004]

Means for Solving the Problems The present inventors have made intensive studies on the relationship between the epoxy resin composition and the mechanical strength, and have completed the present invention. That is, the epoxy resin modifier according to the first aspect of the present invention comprises a rubbery polymer (a
1) At least one monomer compound (a2) 2 selected from the group of vinyl compounds in the presence of 30 to 80% by weight
It is obtained by graft polymerization of 0 to 70% by weight [where (a1) + (a2) = 100% by weight] and contains a graft polymer having the following properties. Characteristics: 20% by weight of the above graft polymer is methyl ethyl ketone 80
The average particle size determined by the dynamic light scattering method when added to the weight% is 50 nm or more and 600 nm or less, and the solution viscosity is 500 mPa · s or less.

[0005] The epoxy resin modifier contains a graft polymer and an organic solvent, and the graft polymer can be dispersed in the organic solvent. The organic solvent that can be used is not particularly limited, but a resist solvent is preferably used. For example, xylene, toluene, butanol, ethyl acetate, butyl acetate, N, N-dimethylformamide, methyl isobutyl ketone, methyl ethyl ketone, propylene glycol monomethyl Ether acetate, ethyl ethoxypropionate, cyclohexanone and the like can be mentioned. Of these, N, N-dimethylformamide, methyl ethyl ketone and propylene glycol monomethyl ether acetate are preferably used.

The epoxy resin modifier of the present invention can be prepared by using the above graft polymer alone as an epoxy resin modifier, or using a known stabilizer, plasticizer, flame retardant, flame retardant auxiliary, or oxidizing agent for the graft polymer. An epoxy resin modifier containing an antistatic agent, an antistatic agent or the like may be used. Further, it can be used either in a solid state or in a liquid state in which these are dispersed using an organic solvent as described above.

The epoxy resin composition according to the third aspect of the present invention comprises: (B) 100 parts by weight of an epoxy resin;
Or (A) 1 to 100 parts by weight of the graft polymer contained in the epoxy resin modifier described in (2).

The rubbery polymer (a1) relating to the above-mentioned epoxy resin modifier is not particularly limited as long as it is a polymer showing rubbery properties. Examples thereof include polybutadiene, hydrogenated polybutadiene, styrene-butadiene copolymer, and styrene. -Isoprene copolymer, butadiene-acrylonitrile copolymer, ethylene-propylene (non-conjugated diene) copolymer, ethylene-butene-1- (non-conjugated diene) copolymer, isobutylene-isoprene copolymer, acrylic rubber Styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated diene (block, random or homo) (co) polymers such as SEBS, polyurethane rubber and silicone rubber. Can be Examples of the styrene-butadiene copolymer include a styrene-butadiene random copolymer, a styrene-butadiene block copolymer, and a hydrogenated product of a styrene-butadiene block copolymer. Among these, preferred rubbery polymers are polybutadiene, styrene-butadiene copolymer, and butadiene-acrylonitrile copolymer. The rubbery polymer of the present invention can be used alone or in combination of two or more.

The "vinyl monomer compound" used in the polymerization in the presence of the rubbery polymer includes (1) styrene, t-butylstyrene, octylstyrene, α-methylstyrene, methyl-α-methyl Styrene, p-methylstyrene, ethylstyrene, α-ethylstyrene, vinyltoluene, vinylxylene, vinylpyridine, dimethylstyrene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethylstyrene, N, N- Aromatic vinyl monomers such as diethyl-p-aminomethylstyrene, divinylbenzene, monochlorostyrene, dichlorostyrene, trichlorostyrene, monobromostyrene, dibromostyrene, tribromostyrene, fluorostyrene, vinylnaphthalene, and sodium styrenesulfonate;
(2) vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, (3) methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, amyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, benzyl acrylate, glycidyl acrylate, trimethylolpropane triacrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, Isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate Relate, t- butyl methacrylate, amyl methacrylate, n- hexyl methacrylate, n- octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate,
Examples include (meth) acrylate monomers such as phenyl methacrylate, benzyl methacrylate, glycidyl methacrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, and allyl methacrylate. Among these, preferred monomer compounds are styrene, divinylbenzene and methyl methacrylate. These can be used alone or in combination of two or more.

In addition to the above monomer compounds, if necessary, polymerizable monomer compounds such as unsaturated acid anhydrides,
Unsaturated acids, unsaturated compounds containing an amino group, imide compounds of unsaturated dicarboxylic acids and the like can be used. As unsaturated acid anhydrides, maleic anhydride, itaconic anhydride,
And citraconic anhydride. As unsaturated acids,
Examples include acrylic acid and methacrylic acid. Examples of the amino group-containing unsaturated compound include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, and diethylaminoethyl methacrylate. As an imide compound of an unsaturated dicarboxylic acid, maleimide, N-methylmaleimide, N-butylmaleimide, N-phenylmaleimide,
N- (2-methylphenyl) maleimide, N- (4-hydroxyphenyl) maleimide, N-cyclohexylmaleimide and the like can be mentioned. These can be used alone or in combination of two or more.

In the preparation of the above graft polymer, when the monomer compound (a2) is graft-polymerized in the presence of the rubbery polymer (a1), the component (a1) contains 30
To 80% by weight (more preferably 40 to 75% by weight, still more preferably 45 to 70% by weight), and the component (a2) is 20 to 80% by weight.
70% by weight (more preferably 25 to 60% by weight, still more preferably 30 to 55% by weight) [where (a) + (b) =
100% by weight]. When the component (a1) is less than 30% by weight, the fracture toughness coefficient becomes small, and when it exceeds 80% by weight, the viscosity at the time of dispersing the epoxy resin becomes high,
Handling becomes difficult, and both are not preferred. The graft ratio of the graft polymer is preferably 25 to 200% by weight, more preferably 30 to 150% by weight. The method for measuring the graft ratio is described in Examples.

When 20% by weight of the above graft polymer is added to 80% by weight of methyl ethyl ketone, the average particle size by dynamic light scattering is 50 nm or more and 600 nm or less, more preferably 50 nm or more and 500 nm or less, and further preferably. 100 nm or more and 500 nm or less. 5
If it is less than 0 nm, the viscosity of the epoxy resin composition increases, and if it exceeds 600 nm, aggregation occurs in the epoxy resin, and the effect of improving various physical properties is not exhibited.

The solution viscosity when adding 20% by weight of the above graft polymer to 80% by weight of methyl ethyl ketone is preferably 500 mPa · s or less.
If it exceeds mPa · s, the dispersibility in the epoxy resin is poor, and the effect of improving various physical properties is not exhibited.

Examples of the method for obtaining the above graft polymer include emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization. Emulsion polymerization and solution polymerization are preferably used. still,
In producing the above graft polymer, the rubbery polymer (a1) and the vinyl monomer compound (a2) are added together with the vinyl monomer compound in the presence of the total amount of the rubber polymer. And may be divided or continuously added for polymerization. Further, the whole or a part of the rubbery polymer may be added during the polymerization to carry out the polymerization.

When producing by emulsion polymerization, a polymerization initiator,
Chain transfer agents (molecular weight regulators), emulsifiers, water and the like are used. Examples of the polymerization initiator include a combination of an organic hydroperoxide such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, or paramenthane hydroperoxide, and a reducing agent such as a sugar-containing pyrophosphate formulation or a sulfoxylate formulation. Or persulfates such as potassium persulfate, azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), lauroyl peroxide, t-
Peroxides such as butylperoxylaurate and t-butylperoxymonocarbonate are exemplified. The polymerization initiator can be added all at once or continuously. Further, the amount of the polymerization initiator used is usually 0.1 to 3.0% by weight, preferably 0.1 to 3.0% by weight based on the total amount of the vinyl monomer compound.
~ 1.5% by weight.

Examples of the chain transfer agent include n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan,
Mercaptans such as t-tetradecyl mercaptan, hydrocarbons such as tetraethylthiuram sulfide, carbon tetrachloride, ethylene bromide, pentaphenylethane, terpenes, or acrolein, methacrolein, allyl alcohol, 2-ethylhexyl thioglycol, α A dimer of methylstyrene. These chain transfer agents can be used alone or in combination of two or more. Examples of the method of adding the chain transfer agent include batch addition, divisional addition, continuous addition, and a combination thereof. The amount of the chain transfer agent used is 0.05 to 2.0% by weight based on the total amount of the vinyl monomer compound.

As the emulsifier used in the case of emulsion polymerization, anionic surfactants, nonionic surfactants, amphoteric surfactants and the like can be used. Among them, examples of the anionic surfactant include sulfates of higher alcohols, alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, aliphatic sulfonates such as sodium lauryl sulfate, higher aliphatic carboxylate, phosphorus Acid salts and the like. As the nonionic surfactant, an alkyl ester type, an alkyl ether type, an alkyl phenyl ether type or the like of ordinary polyethylene glycol is used. Further, as the amphoteric surfactant, a carboxylate, a sulfate, a sulfonate,
Examples of the phosphate ester salt include those having an amine salt, a quaternary ammonium salt, or the like as a cation moiety. These emulsifiers can be used alone or in a combination of two or more. Examples of the method for adding the emulsifier include batch addition, divisional addition, continuous addition, and a combination thereof. The amount of the emulsifier used is 0.1 to the total amount of the vinyl monomer compound.
It is about 3 to 5.0% by weight. In the above emulsion polymerization,
The preferred polymerization temperature is from 10 to 95 ° C, more preferably from 30 to 95 ° C.

When the above graft polymer is produced by emulsion polymerization, usually, the powder obtained by coagulation with a coagulant is washed with water, dried and purified to obtain a powder.
Examples of the coagulant include acids such as sulfuric acid, acetic acid, and hydrochloric acid, and inorganic salts such as magnesium sulfate, aluminum sulfate, calcium chloride, magnesium chloride, and sodium chloride. It is preferably used. In addition, spray drying with a spray dryer may be performed without coagulation. Further, atomizer coagulation, which is a spray coagulation method, may be performed.

In the epoxy resin composition of the present invention, the compounding amount of the epoxy resin modifier is 1 to 100 parts by weight, preferably 1 to 80 parts by weight, in terms of solid content based on 100 parts by weight of the epoxy resin. Parts, more preferably 1 to 50
Parts by weight. If the amount is less than 1 part by weight, the effect of improving the low stress of the epoxy resin is not exhibited, and if it exceeds 100 parts by weight,
The viscosity at the time of dispersing the epoxy resin becomes high, which is not preferable.

The "(B) epoxy resin" to be blended as the epoxy resin composition of the present invention includes bisphenol A type epoxy resin, bisphenol F type epoxy resin, cresol novolak type epoxy resin, phenol novolak type epoxy resin, cyclic fat Group-type epoxy resins, long-chain aliphatic type epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, isocyanate type epoxy resins, dimer acid modified epoxy resins, NBR modified epoxy resins, urethane modified epoxy resins and the like. When a cured product is obtained, a curing agent and a curing accelerator can be applied depending on the purpose of use.

The epoxy resin composition of the present invention may contain, if necessary, known stabilizers, plasticizers, flame retardants, flame retardant auxiliaries, antioxidants, softeners, various inorganic or organic fillers, reinforcing materials. An additive such as an agent, a cross-linking agent, an antistatic agent, a coloring agent, a coupling agent, a viscosity modifier, a weathering agent, a lubricant, and silicone oil can be blended.

When a cured product of the above epoxy resin composition is obtained, the curing agent may be diethylenetriamine, triethylenetetramine, isophoronediamine, ethylenediamine, m-phenylenediamine, hexamethylenediamine, diethylenetriamine, tetraethylenepentamine, piperidine, N , N'-dimethylpiperazine, 1,
4-diazadicyclo (2,2,2) octane, pyridine, picoline, benzyldimethylamine, 2- (dimethylaminomethyl) phenol, DBU (1,8-diazabicyclo [5.4.0] -7-undecene), dimethyl Benzylamine, dimethylcyclohexylamine, dimethylhexylamine, dimethylaminomethylphenol, dimethylamino p-cresol, tetraethylenepentamine, N-aminoethylpiperazine, trisdimethylaminomethylphenol, dicyandiamide, 4,
4'-diaminodiphenyl sulfone, 2-n-heptadecyl imidazole, melamine, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride Acid, endomethylenetetrahydrophthalic anhydride, dodecenylsuccinic anhydride, hexahydrophthalic anhydride, chlorendic anhydride, boron trifluoride-monoethylamine and the like. These can be used alone or in combination of two or more.

The amount of the curing agent used depends on the purpose.
1 to 200 parts by weight per 100 parts by weight of the epoxy resin,
Preferably, it is used in the range of 1 to 180 parts by weight. In addition, a tertiary amine is generally used as a curing accelerator,
Others include 2-ethyl-4-methylimidazole, D
BU, quaternary phosphonium salts, amine imides, triphenylphosphine and the like. The curing accelerator is used in an amount of 0.1 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the epoxy resin.

The method for curing the epoxy resin composition of the present invention includes the following methods and the like, which can be appropriately selected according to the application. The curing temperature is
The temperature ranges widely from room temperature to 200 ° C., and varies greatly depending on the type of curing agent used. (B) A method in which (A) an epoxy resin modifier is directly added to an epoxy resin, dissolved and dispersed, and then a curing agent, a curing accelerator, and other additives are added, followed by curing at a predetermined temperature. (A) Epoxy resin modifier is converted into an organic solvent [xylene, toluene, butanol, ethyl acetate, butyl acetate, cellosolve (methyl, ethyl or butyl mono or diether), N, N-dimethylformamide, methyl ethyl ketone, methyl isobutyl ketone , Propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, cyclohexanone, and other solvents for resists], and then added to (A) the epoxy resin, and the solvent was distilled off to obtain a curing agent, a curing accelerator, and the like. A method of adding an additive and heating at a predetermined temperature to cure. In the above method, the solvent is cured without removing the solvent.

The above (B) epoxy resin, (A) epoxy resin modifier and curing agent and other methods of mixing may be performed by a conventional processing machine such as a disper, kneader, planetary mixer, paddle mixer, intermixer, homomixer. , A Banbury mixer, various extruders and the like. The epoxy resin composition of the present invention can be molded by a molding method such as compression molding, lamination molding, transfer molding, cast molding, and press molding.

According to a fourth aspect of the present invention, there is provided a circuit board including an insulating layer or an insulating portion formed by using the epoxy resin composition. An IC sealing material according to a fifth aspect of the present invention includes a sealing layer or a sealing portion formed by using the epoxy resin composition.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In Examples and Comparative Examples, parts and percentages are by weight unless otherwise specified.

1. Evaluation method The evaluation method used in this example is as follows. (1) Measurement of average particle diameter of epoxy resin modifier The average particle diameter was measured by a light scattering method. The measurement was carried out by adding (A) 20% by weight of a graft polymer as an epoxy resin modifier to 80% by weight of methyl ethyl ketone, followed by shaking for 10 minutes, and a laser particle size analysis system LPA-3100 manufactured by Otsuka Electronics Co., Ltd. The measurement was performed using a cumulant method in a total of 70 times.

(2) Viscosity (A) Graft polymer 20 as epoxy resin modifier
% By weight was added to 80% by weight of methyl ethyl ketone, and the solution was measured using a BM type viscometer. The measurement temperature is 2
Performed at 5 ° C. The viscosity of the epoxy resin composition in which 18 parts by weight of the epoxy resin modifier (A) was dispersed in 100 parts by weight of the epoxy resin (B) was measured using a BH type viscometer manufactured by TOKIMECINIC CO., LTD. The measurement was performed at 25 ° C.

(3) Graft ratio A certain amount (W1) (about 1.0 g) of the graft polymer is weighed and placed in a 100 ml Meyer flask. 20 ml of acetone was added thereto, and the mixture was shaken with a shaker for 2 hours to dissolve the free polymer, and then centrifuged at 23,000 rpm.
centrifugation at pm for 1 hour to separate insoluble and soluble components,
The insolubles were dried at 120 ° C. for 2 hours using a vacuum dryer,
The weight of the soluble matter (W2) and the insoluble matter (W3) after drying was measured, and the graft ratio was calculated from the following equation. Soluble fraction (%) = (W2 / W1) × 100 Insoluble fraction (%) = (W3 / W1) × 100 Insoluble content (%) = [insoluble fraction / (soluble fraction + insoluble fraction) Rate)] × 100 Conversion rate of monomer in graft polymer (%) = C Rubbery polymer content (polymerization charge value) (%) = R Rubbery polymer content in graft polymer in terms of conversion rate ( %) = {R / [R + (100−R) × C / 100]}
× 100 Graft rate (%) = [(insoluble matter content−converted rubber polymer content) / converted rubber polymer content] × 100

(4) Dissolution and dispersibility The state of the epoxy resin composition obtained by dissolving and dispersing the (A) epoxy resin modifier in the (B) epoxy resin was visually judged according to the following criteria. A: Completely dissolved and dispersed. ：: Some undissolved parts (bubbles) are present. X: Half or more insoluble parts (bubbles) are present.

(5) Evaluation of physical properties of cured epoxy resin composition Flexural strength: Measured according to JIS K6911. Flexural modulus: Measured according to JIS K6911. Fracture toughness coefficient: Measured according to JIS K6911.

2. Preparation of rubbery polymer As a rubbery polymer, a polybutadiene latex was obtained by emulsion polymerization of 1,3-butadiene.

3. Preparation of Epoxy Resin Modifier In a separable flask equipped with a dropping bottle, a condenser, a nitrogen inlet and a stirrer, 50 parts of the above rubbery polymer in terms of solid content, 0.1 part of potassium rosinate as an emulsifier,
And 100 parts of water were mixed, followed by addition of 5 parts of divinylbenzene. The temperature was raised to 65 ° C., and when the temperature reached 65 ° C., 0.2 parts of sodium pyrophosphate and 0.25 g of glucose were added.
Part, ferrous sulfate (0.01 part) was added, and subsequently, cumene hydroperoxide (0.2 part) was added and reacted for 1 hour. Thereafter, 35 parts of methyl methacrylate, 10 parts of styrene, 20 parts of water, and 1 part of potassium rosinate were added dropwise over 4 hours, and the mixture was further reacted for 1 hour. The polymerization conversion is 9
7.5%. The obtained polymer is coagulated with sulfuric acid,
The coagulated product was thoroughly washed with water and dried to obtain a powdery graft polymer, which was then modified with an epoxy resin modifier (A-
1) (see Table 1). Similarly, by changing the compounding amount of the rubbery polymer, the amount of the chain transfer agent used, the compounding ratio, the polymerization temperature, the polymerization time, and the like, a graft polymer is obtained, and these are used as the epoxy resin modifier as described above. (A-2) to (A-6)
(Table 1).

[0035]

[Table 1]

4. Examples 1 to 4, Comparative Examples 1 to 9 (1) Method (Examples 1 and 2 and Comparative Examples 1 to 7) 100 parts by weight of the following (B) epoxy resin was homogenized according to the formulation shown in Tables 2 and 3. The mixture was stirred at a rotational speed of 500 rpm with a mixer, and (A) a graft polymer as an epoxy resin modifier was gradually added. Thereafter, the rotation speed was increased to 6,000 rpm, and the mixture was stirred for 2 hours. After defoaming under reduced pressure, 80 parts by weight of the following curing agent and 1 part by weight of a curing accelerator were added and stirred at room temperature to obtain epoxy resin compositions according to Examples 1 and 2 and Comparative Examples 1 to 7. . This resin composition was measured for viscosity and visually evaluated for dissolution and dispersibility. next,
This was poured into a mold and heat-cured under the conditions of 90 ° C./2 hours and 120 ° C./1 hour to obtain a cured product of the epoxy resin composition, which was then subjected to various evaluations. Tables 2 and 3 show the evaluation results. (2) Method (Examples 3 and 4, Comparative Examples 8 and 9) While stirring methyl ethyl ketone with a stirrer at a rotation speed of 100 rpm, (A) an epoxy resin modifier was added so as to have a solid content of 20% by weight. Then, the following (B) epoxy resin is added so that the compounding recipe shown in Tables 2 and 3 is obtained. Thereafter, methyl ethyl ketone was distilled off and defoamed under reduced pressure to obtain epoxy resin compositions according to Examples 3 to 4 and Comparative Examples 8 to 9. This resin composition was measured for viscosity and visually evaluated for dissolution and dispersibility.
Next, this is poured into a mold, and 90 ° C./2 hours, 120 ° C.
After heating and curing under the condition of / 1 hour to obtain a cured product of the epoxy resin composition, various evaluations were performed. Tables 2 and 3 show the evaluation results. (A) Epoxy resin; Epicoat 828 (manufactured by Yuka Shell Epoxy), viscosity: 12 to 15 Pa · s, epoxy equivalent: 184 to 194 (A) Curing agent: ADEKA HARDNER H3326 (manufactured by Asahi Denka Co.) (C) Curing accelerator Ankamin K-54 [AC
(I Japan)

[0037]

[Table 2]

[0038]

[Table 3]

From the results shown in Table 3, in Comparative Example 1, since the amount of the component (A) was less than 1 part by weight in the composition of the components (A) and (B), the stress and the fracture toughness coefficient were lower. No improvement effect is exhibited. In Comparative Example 2, since the compounding amount of the component (A) exceeded 100 parts by weight, the viscosity at the time of dispersing the epoxy resin was increased, and various physical properties were reduced. In Comparative Example 3,
Since the amount of the rubbery polymer was less than 30 parts by weight (Table 1), the fracture toughness coefficient was lowered. In Comparative Example 4, since the amount of the rubbery polymer exceeded 80 parts by weight, aggregation occurred in the epoxy resin, and the effect of improving various physical properties was not exhibited. In Comparative Example 5, since the average particle diameter of the component (A) in methyl ethyl ketone was less than 50 nm, the viscosity of the epoxy resin composition was significantly increased. In Comparative Example 6, since the average particle diameter of the component (A) in methyl ethyl ketone exceeds 600 nm, aggregation of the component (A) in the epoxy resin occurs, and the effect of improving various physical properties is not exhibited. In Comparative Example 7, the solution viscosity of methyl ethyl ketone containing the component (A) was 5
Since it exceeds 00 mPa · s (Table 1), the dispersibility in the epoxy resin is poor, and the effect of improving various physical properties is not exhibited. In Comparative Example 8, since the amount of the rubbery polymer was less than 30 parts by weight, the fracture toughness coefficient decreased. In Comparative Example 9, since the amount of the rubbery polymer exceeded 80 parts by weight (Table 1), aggregation occurred in the epoxy resin, and the effect of improving various physical properties was not exhibited. On the other hand, in the examples, the viscosity of the epoxy resin composition was much lower than in the comparative example, and the dispersion state by visual observation was also good. The physical properties of the cured product were excellent in flexural strength and fracture toughness coefficient. In particular, in the fracture toughness coefficient, the average value of the comparative example was 0.78 and the average value of the examples was 1.60, which was twice or more.

The present invention is not limited to the above embodiment, but can be variously modified according to the purpose and application. A circuit board provided with an insulating layer using the epoxy resin composition of the present invention is formed, for example, as shown in FIG. That is, the substrate 1 made of paper phenol or glass epoxy, etc.
A copper plating layer 2 is formed on the surface (see FIG. 1A) (see B), and the conductive pattern 2a is left by etching (see C). An epoxy resin composition containing an epoxy resin modifier in which the graft polymer is dispersed by an organic solvent is applied thereto, and the coating film is dried and cured by heating to form an interphase insulating film 3 (see D). . Further, a resist is applied to form a resist layer 4 (see E), a portion to be patterned is removed with an alkali or the like to form a conductive pattern (see F), and the portion is plated with copper (see G). . By removing the remaining resist, a build-up circuit board (see H) having the copper conductive pattern 5 and the insulating portion can be manufactured. This circuit board is
Secondary processing, such as opening a through hole, is also possible as necessary. The circuit board of the present invention is not limited to a build-up circuit board, but may be a single-layer circuit board. The material for forming the conductive pattern may be other than copper.

As shown in FIG. 2, for example, as shown in FIG. 2, an IC substrate provided with a sealing portion using the epoxy resin composition of the present invention is a wiring pattern of copper or the like on a printed circuit board 6 (not shown).
The IC 7 is sealed 8 by applying, drying and curing the epoxy resin composition. As an example of the sealing method in this case, there is a method in which an epoxy resin composition dispersed in an organic solvent is applied to a sealing portion, and dried and cured.

[0042]

The epoxy resin modifier of the present invention has an average particle diameter of from 50 nm to 600 nm when 20% by weight of the epoxy resin modifier is added to methyl ethyl ketone, and a solution viscosity of 500 mPa · s or less. By being in the range, the dispersibility and the viscosity (low viscosity) in the epoxy resin are excellent. The epoxy resin modifier can be used in a solid state or in a solvent-dispersed state dispersed in an organic solvent. A cured product of an epoxy resin composition comprising an epoxy resin and an additive compounded as required has excellent mechanical properties. Therefore, utilizing its properties, electronic materials such as a circuit board having an insulating layer or an insulating portion and an IC sealing material having a sealing layer or a sealing portion, as well as undercoat paints, powder paints, and civil engineering for metals.・ Structural adhesives for construction applications, sealing agents, adhesives for electric and electronic materials,
It can be used in a wide range of fields such as adhesives for printed wiring and adhesives for laminated boards. The circuit board and the IC encapsulant of the present invention are excellent in processability due to the low viscosity of the epoxy resin composition.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory views showing a process of manufacturing a circuit board according to the present invention, wherein FIG. 1A is a cross-sectional view showing an original board, FIG. ) Is a cross-sectional view showing a state where the conductive pattern is left by the etching process, (D) is a cross-sectional view showing a state where an epoxy resin composition is applied, (E) is a cross-sectional view showing a state where a resist is applied, (F) is a cross-sectional view showing a state where the resist at the portion where the conductive pattern is to be provided is processed, (G) is a cross-sectional view showing a state where the processed resist is copper-plated, and (H) is a completed circuit board. FIG.

FIG. 2 is an explanatory sectional view showing an IC sealing material of the present invention.

[Explanation of symbols]

1; substrate; 2; copper plating layer; 2a; conductive pattern;
Interphase insulating layer, 4; resist layer, 4a; resist pattern, 5; conductive pattern, 6; substrate, 7; IC, 8;

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 23/31 H05K 1/03 610S H05K 1/03 610 H01L 23/30 R (72) Inventor Ryoichi Motoshige 1-18-1 Kyobashi, Chuo-ku, Tokyo Techno Polymer Co., Ltd. F-term (reference) 4J002 BN06W BN14W CD00X CD04X CD05X CD06X GQ00 4J026 AA67 AA68 AC01 AC02 AC11 AC12 BA04 BA05 BA06 BA07 BA08 BA27 BA28 BA31 BB01 BB02 DB03 BB03 DB04 DB05 DB12 DB13 DB15 DB16 GA08 4M109 AA01 BA03 CA10 EA02 EB19 EC03 EC04 5G305 AA06 AA13 AA14 AB15 AB36 BA09 CA15 CA47 CD04

Claims (5)

[Claims] 1. A rubbery polymer (a1) in an amount of 30 to 80% by weight.
Is obtained by graft polymerization of 20 to 70% by weight of at least one monomer compound (a2) selected from the group of vinyl-based compounds (provided that (a1) + (a2) = 100% by weight). An epoxy resin modifier comprising a graft polymer having the following characteristics. Properties: The average particle size by dynamic light scattering when 20% by weight of the above graft polymer is added to 80% by weight of methyl ethyl ketone is 50 nm or more and 600 nm or less, and the solution viscosity is 500 mPa · s or less. 2. The epoxy resin modifier according to claim 1, comprising the graft polymer and an organic solvent, wherein the graft polymer is dispersed in the organic solvent. 3. A composition comprising (B) 100 parts by weight of an epoxy resin and 1 to 100 parts by weight of a graft polymer contained in the epoxy resin modifier (A) according to claim 1 or 2. A characteristic epoxy resin composition. 4. A circuit board comprising an insulating layer or an insulating portion formed using the epoxy resin composition according to claim 3. 5. An IC sealing material comprising a sealing layer or a sealing portion formed using the epoxy resin composition according to claim 3.