JP2000038439A - Epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition producing the cured product having excellent heat resistance and excellent adhesion to metals, other inorganic materials and the cured product itself by adding hydroxy group- substituted aromatic compounds bound to each other through a specific group to an epoxy resin. SOLUTION: This epoxy resin composition comprises (A) an epoxy resin (for example, a bisphenol type epoxy resin) and (B) a compound having a structure where the molecules of a hydroxy group-substituted aromatic compound are bound to each other through a group of formula I (R is H, a halogen or a 1-6C alkyl) preferably a compound having a structure of formula II [X is H, methyl, ethyl, propyl or t-butyl; (n) is 1-4]} as a curing agent preferably so that the ratio of the phenolic hydroxy groups of the phenol compound of component B to the epoxy groups in the component A are 0.2-2.0 to 1. The curing agent of component B is obtained, for example, by reacting a cyanuric acid halide with an aromatic compound having an amino group and a hydroxy group as substituents on the aromatic ring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a semiconductor encapsulant, which has excellent adhesiveness to inorganic materials such as metals and silicon chips, or adhesiveness between cured products, and excellent heat resistance of cured products. Epoxy resin compositions that can be used for laminated component materials, electrical insulating materials, fiber reinforced composite materials, coating materials, molding materials, adhesive materials, etc., and are particularly useful as semiconductor sealing materials and compositions for printed wiring laminates .

[0002]

2. Description of the Related Art Conventionally, epoxy resin compositions used in combination of an epoxy resin and a curing agent have been used in semiconductor encapsulating materials, printed wiring laminates, etc. because of their excellent electrical performance and cured product strength. Widely used. In semiconductor encapsulant applications, excellent curability and heat resistance,
A composition combining a cresol novolak type epoxy resin and a phenol novolak resin is widely used. On the other hand, as the epoxy resin used for the printed wiring board, a brominated bisphenol A type epoxy resin is generally used, and depending on the application, a phenol novolak type epoxy resin or cresol Novolak-type epoxy resins and the like are used in combination, and dicyandiamide, which is a latent curing agent, has been used as a curing agent.

[0003]

However, in semiconductor encapsulant applications, as the surface mounting method of semiconductors has become widespread, the solder crack resistance of semiconductor packages has become an important issue. A semiconductor encapsulant combining a cresol novolak type epoxy resin and a phenol novolak resin has excellent heat resistance, but has a problem that solder crack resistance deteriorates due to low adhesion to a lead frame or a silicon chip. I was
On the other hand, in the field of printed wiring laminates, it has become an important required characteristic to have both adhesion to a base material and copper foil and heat resistance in accordance with multilayering, thinning, and higher density of wiring patterns. . However, a system using DICY as the curing agent cannot have satisfactory heat resistance. Also,
A technique using a novolak resin as a curing agent to impart heat resistance is also known, but this system improves heat resistance but does not provide satisfactory adhesion to a substrate and copper foil. Met.

[0004] The problem to be solved by the present invention is that the heat resistance of the cured product is remarkably excellent, and the adhesiveness to metal and other inorganic materials and the adhesiveness between the cured products are excellent. Another object of the present invention is to provide an epoxy resin composition having excellent solder crack resistance during surface mounting, and having excellent heat resistance and excellent adhesion to a substrate and copper foil in a printed wiring board.

[0005]

The inventors of the present invention have conducted intensive studies in view of the above-mentioned drawbacks of the prior art, and have found that a curing agent having the structure represented by the above formula 1 is used as a curing agent for an epoxy resin. Thereby, it was found that a semiconductor encapsulating material having excellent solder crack resistance, and a printed wiring laminate excellent in heat resistance and adhesion to a substrate and copper foil were obtained, and the present invention was completed. .

That is, the present invention provides an epoxy resin composition comprising the epoxy resin (A) and the curing agent (B) as essential components, wherein the curing agent (B) comprises a hydroxyl-substituted aromatic compound represented by the following formula 1

[0007]

Embedded image (R is each independently a hydrogen atom, a halogen atom, or
The present invention relates to an epoxy resin composition having a structure knotted by a group represented by an alkyl group having 1 to 6 carbon atoms).

The epoxy resin (A) used in the present invention is not particularly limited as long as it has at least two epoxy groups in one molecule. For example, bisphenol A type epoxy resin Bisphenol type epoxy resins such as bisphenol AD type epoxy resin, bisphenol F type epoxy resin, bisphenol hexafluoroacetone diglycidyl ether, bisbeta-trifluoromethyldiglycidyl bisphenol A, and tetramethylbisphenol A type epoxy resin; tetrabromobisphenol A type epoxy resin, brominated bisphenol type epoxy resin such as tetramethylbiphenol type epoxy resin and polyadduct of tetrabromobisphenol A and bisphenol A; resorcinoid diglycidyl ether and the like Other bifunctional epoxy resins; diglycidyl ether of dihydroxynaphthalene;
Naphthol novolak epoxy resin, naphthol-phenol co-condensed novolak epoxy resin, naphthalene skeleton-containing epoxy resin such as 1- (2,7-diglycidyloxynaphthyl) -1- (2-glycidyloxynaphthyl) methane;
Novolak type epoxy resins such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, brominated phenol novolak type epoxy resin; alicyclic type represented by dicyclopentadiene-phenol polyaddition type epoxy resin Epoxy resin having a structure; epoxy resin having a cyclohexene oxide group, epoxy resin having a tricyclodecene oxide group, epoxy resin having a cyclopentene oxide group, and other cycloaliphatic epoxy resins such as epoxidized dicyclopentadiene; Acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, diglycidyl P-oxybenzoic acid, dimer acid glycidyl ester Glycidyl ester type epoxy resin such as triglycidyl ester; glycidylamine type epoxy resin such as tetraglycidylaminodiphenylmethane, triglycidyl P-aminophenol, tetraglycidyl m-xylylenediamine; complex such as hydantoin type epoxy resin and triglycidyl isocyanurate Cyclic epoxy resin; trihydroxybiphenyl triglycidyl ether, trihydroxyphenylmethane triglycidyl ether, glycerin triglycidyl ether, 2- [4
-(2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4- (2,3-epoxypropoxy) phenyl] ethyl] phenyl] propane, tetrahydroxyphenylethanetetraglycidyl ether, 1,1-bis (2,7-diglycidyloxynaphthyl) methane, 1,1-bis (2,7-diglycidyloxynaphthyl) -1-phenyl-methanetetraglycidylbenzophenone, bisresorcinol tetraglycidyl ether, tetra 4 such as glycidoxybiphenyl
Functional epoxy resins and the like can be mentioned.

Further, an epoxy resin obtained by copolymerizing (modifying) at least one of the above epoxy resins with a phenol and multifunctionalizing the same may be used. For example, a bisphenol A type epoxy resin and a phenol novolak type epoxy resin may be used. Epoxy resin copolymerized with epoxy resin and tetrabisphenol A, bisphenol A type epoxy resin, orthocresol novolac type epoxy resin and tetrabisphenol A
Epoxy resin with bisphenol A type epoxy resin, bisphenol A type novolak epoxy resin with tetrabisphenol A, bisphenol A type epoxy resin with brominated phenol novolak type epoxy resin with tetrabisphenol Bisphenol A type epoxy resin such as copolymerized epoxy resin with A, bisphenol A type epoxy resin, phenol novolak type epoxy resin and copolymerized epoxy resin with tetrabisphenol A, and various bifunctional and tetrafunctional epoxy resins Epoxy resins copolymerized with a resin and tetrabromobisphenol A are exemplified. Of course, these epoxy resins may be used alone or in a combination of two or more kinds via a phenol. Also, two or more selected from the above epoxy resin group may be mixed and used in combination.

Of these, novolak type epoxy resins, naphthalene skeleton-containing epoxy resins, and dicyclopentadiene-phenol polyaddition type epoxy resins are particularly preferred as semiconductor encapsulating materials because of their excellent solder crack resistance. On the other hand, as a printed wiring board laminate, copolymerization of bisphenol-type epoxy resin, brominated bisphenol-type epoxy resin, or bisphenol A-type epoxy resin with various bifunctional or 4-functional epoxy resins and tetrabromobisphenol A Epoxy resins are preferred because the effects of the present invention such as adhesion and heat resistance become remarkable.

The curing agent (B) used in the present invention comprises:
As described above, the hydroxyl-substituted aromatic compound is represented by the following formula 1

[0012]

Embedded image (R is each independently a hydrogen atom, a halogen atom, or
(Alkyl group having 1 to 6 carbon atoms) having a structure knotted by the group, whereby the heat resistance of the cured product is remarkably improved, and the adhesion, that is, metal or other Adhesion to inorganic materials and adhesion between cured products are dramatically improved.

R in the above formula 1 is specifically a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a linear alkyl group having 1 to 10 carbon atoms, Any alkyl group can be used, but a hydrogen atom is preferred because of its excellent balance between adhesion and heat resistance.

There is no particular limitation on the hydroxyl-substituted aromatic compound in the curing agent (B).
, Dihydroxybenzene, trihydroxybenzene,
Hydroxyl group-containing benzenes such as tetrahydroxybenzene and pentahydroxybenzene, hydroxyl-containing naphthalenes such as monohydroxynaphthalene, dihydroxynaphthalene, trihydroxynaphthalene, tetrahydronaphthalene, pentahydronaphthalene, hexahydronaphthalene, heptahydronaphthalene, and hydroxyl group Containing anthracenes, and further, any of these aromatic ring skeletons can be used any or all of the compounds in which part or all of the hydrogen in the aromatic ring skeleton is substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aromatic ring. Hydroxybenzenes are preferred because they have an excellent balance of heat resistance, and among them, monophenol is more preferred from the viewpoint of cost, in addition to the balance between adhesion and heat resistance. Therefore, as a specific structure of the curing agent (B), the following formula 2

[0015]

Embedded image (X is each independently a hydrogen atom, a methyl group, an ethyl group, a propyl group or a t-butyl group, and n is an integer of 1 to 4.).

The method for obtaining the curing agent (B) is not particularly limited. For example, a cyanuric halide and an aromatic compound having an amino group and a hydroxyl group as substituents on an aromatic ring (hereinafter referred to as aminophenol) And abbreviations).

The cyanuric halide includes 2, 4,
Any of 6-trifluoro-1,3,5-triazine, 2,4,6-trichloro-1,3,5-triazine and the like can be used, but 2,4,6-trichloro-1 is inexpensive. , 3,5-
Triazines are preferred.

Aminophenols to be reacted with cyanuric halides include P-aminophenol, m-aminophenol, o-aminophenol, dihydroxyaniline, trihydroxyaniline, tetrahydroxyaniline, pentahydroxyaniline. Such as amino-hydroxy-benzenes, monohydroxynaphthylamine, dihydroxynaphthylamine, trihydroxynaphthylamine, tetrahydronaphthylamine, pentahydronaphthylamine, hexahydronaphthylamine, and hydroxyl group-containing naphthylamine such as heptahydronaphthylamine; Although it can be used, amino-hydroxy-benzenes, especially P Monoaminophenols such as aminophenol, m-aminophenol, o-aminophenol, etc.
Are preferred.

As a reaction method, specifically, a cyanuric halide and an aminophenol are respectively dissolved in a solvent in such a ratio that a ratio of a halogen atom to an amino group becomes 1: 2. The solvent used here is not particularly limited as long as it can dissolve both cyanuric halide and aminophenols.Examples include ketone solvents such as acetone and methyl ethyl ketone, dioxane, N, N-dimethylformamide and the like. Aprotic polar solvent and the like.

Next, in a solution of aminophenols,
A solution of cyanuric halide is added dropwise at a temperature of 0 to 20 ° C, and after the addition, the temperature is raised to 40 to 100 ° C to carry out the reaction. After the completion of the reaction, the solvent is removed by distillation, followed by washing with water. Then, a method for obtaining the desired phenol compound (B) can be mentioned.

The mixing ratio of the epoxy resin and the phenol compound (B) in the present invention is such that the phenolic hydroxyl group of the phenol compound (B) is 0.2 to 2.0 per one epoxy group in the epoxy resin. Within the percentage range,
Preferably, it is 0.5 to 1.5. If the amount of the phenol compound (B) is larger than this range, unreacted phenol may be present to cause a problem such as a decrease in hygroscopicity. ) Gets worse.

Various curing accelerators can be used in the epoxy resin composition of the present invention.
For example, tertiary amines such as benzyldimethylamine,
Known and commonly used compounds such as various imidazoles, tertiary phosphines and various metal compounds can be applied.

In the epoxy resin composition of the present invention,
Further, if necessary, an inorganic filler (C) can be used in combination. In particular, when the epoxy resin composition of the present invention is used for a semiconductor sealing material, an inorganic filler (C) is an essential component in addition to the components (A) and (B).

The inorganic filler (C) is not particularly restricted but includes, for example, crystalline silica, fused silica, alumina, talc, clay, glass fiber and the like. Among these, crystalline silica and fused silica are particularly preferred for semiconductor encapsulant applications. In addition, among the fused silicas, the use of spherical silica can dramatically improve the fluidity during molding.

In the epoxy resin composition of the present invention, an organic solvent (D) can be used, if necessary, in addition to the above components. In particular, when preparing a varnish for a printed wiring laminate, the components (A), (B), and (D) are essential components. Of course, when used for other purposes such as paint applications, the components (A), (B), (C) and (D) may be used in combination.

The organic solvent (D) is not particularly restricted but includes, for example, acetone, methyl ethyl ketone, toluene, xylene, methyl isobutyl ketone, ethyl acetate, ethylene glycol monomethyl ether,
N, N-dimethylformamide, methanol, ethanol, isopropyl alcohol, n-butanol, methoxypropanol, ethyl carbitol, toluene, cyclohexanol and the like. These solvents can be used as a mixture of two or more solvents as appropriate.

The amount of the organic solvent (D) to be used is not particularly limited, but the effect of improving the adhesion to the substrate and the copper foil when forming a laminate, measling, crazing, etc.
The solid content concentration is preferably in the range of 40 to 100% by weight, especially 50 to 70% by weight, since the effect of preventing delamination is excellent.

Various additives, flame retardants, fillers, and the like can be appropriately added to the epoxy resin composition of the present invention, if necessary.

[0029]

EXAMPLES Synthesis Example 1 [Synthesis example of curing agent] 62.1 g (570 mmol) of P-aminophenol
Was placed in a 1-liter four-necked flask and stirred with a nitrogen purge. After cooling the periphery of the flask with ice water to bring the solution temperature to 10 ° C., an acetone solution containing 17.5 g (95 mmol) of cyanuric chloride
150 ml using a dropping funnel while paying attention to heat generation.
It was added dropwise over time (reaction temperature 10 ± 5 ° C.). After the temperature was raised to 56 ° C. over 1 hour, it was held at 56 ° C. for 3 hours. After removing acetone with an evaporator, the mixture was washed four times with 700 ml of distilled water (agitated and filtered four times with an auto homomixer) to obtain a whitish brown solid in a yield of about 65%. I got it. This was designated as curing agent (I).

Examples 1 to 4 and Comparative Examples 1 to 4 The mixtures prepared according to the formulations shown in Table 1 were kneaded at 100 ° C. for 8 minutes with a hot roll to obtain an epoxy resin composition. 1200 to 1400 kg
/ Cm ² at a pressure of 80 kg / cm ² using a transfer molding machine.
The package was sealed under the conditions of cm ² , a mold temperature of 175 ° C., and a molding time of 100 seconds, and a 20 mm-thick 20-pin flat package was prepared as a test piece for evaluation. Using this test piece for evaluation, the glass transition temperature and the tensile elasticity (adhesion) with a lead frame (copper) at 250 ° C. were measured by a dynamic viscoelasticity measuring device (DMA). Further, 20 test pieces were left in an atmosphere of 85 ° C. and 85% RH for 168 hours to perform a moisture absorption treatment, and then immersed in a 260 ° C. solder bath for 10 seconds. The crack occurrence rate at that time was used as an index of solder crack resistance. Table 1 shows the evaluation results.

In Table 1, "N-665-EXP" is a cresol novolak type epoxy resin (trade name: EPICLON N-66, manufactured by Dainippon Ink and Chemicals, Inc.).
5-EXP, softening point 68 ° C, epoxy equivalent 205g / e
q), “TD-2131” is a phenol novolak resin (trade name: Phenolite TD-2131, manufactured by Dainippon Ink and Chemicals, softening point 80 ° C., hydroxyl equivalent 10)
4 g / eq), RD-8 is fused silica (Tatsumori, crushed silica having an average particle size of 15 μm), and “TPP” is triphenylphosphine.

[0032]

[Table 1]

Next, a varnish was prepared according to the composition shown in Table 2. Varnish is the main ingredient (methyl ethyl ketone solution)
Each curing agent previously dissolved in a solvent is added, and the curing agent 2 is added thereto.
After the addition of -ethyl-4-methylimidazole, the final nonvolatile content (N.V.) of the formulated epoxy resin composition was 5%.
It was prepared by adjusting with methyl ethyl ketone to be 5%. Methyl ethyl ketone was used for dissolving the curing agent.
However, when dicyandiamide is used as a curing agent, N, N
-Dimethylformamide was used. The main agent is a polyaddition type epoxy resin of bisphenol A type epoxy resin and tetrabromobisphenol A (manufactured by Dainippon Ink and Chemicals, Inc., trade name: EPICLON 1121-75)
M, epoxy equivalent 495 g / eq, bromine content 21% by weight).

At this time, the amount of the curing agent was compounded in such a ratio as to be 1.0 equivalent to the epoxy equivalent in the base epoxy resin. However, in the case of dicyandiamide, it was blended at a ratio of 0.5 equivalent to the epoxy equivalent in the base epoxy resin. Further, the curing accelerator was used in a ratio of 0.1 part with respect to 100 parts of the epoxy resin as the main component.
Thereafter, each mixed solution was cured under the following conditions to produce a double-sided copper-clad laminate. Table 2 shows the evaluation results.

In Table 2, "N-690-75M" is a cresol novolak type epoxy resin (trade name: EPICLON N-69, manufactured by Dainippon Ink and Chemicals, Inc.).
0-75M, epoxy equivalent 220 g / eq), "TD-
2090 ”is a phenol novolak resin (Denippon Ink Chemical Industry Co., Ltd. product name: Phenolite TD-2)
090, softening point 120 ° C, hydroxyl equivalent 105g / e
q) 2E4MZ represents 2-ethyl-4-methyl-imidazole.

[Lamination board production conditions] Base material: 180 μm; Glass cloth “WLA180107BZ” manufactured by Nitto Boseki Co., Ltd. Number of plies: 8 Pre-preg formation condition: 160 ° C./3 minutes Copper foil: 35 μm; Furukawa Circuit Wheel Co., Ltd. Curing conditions: 170 ° C, 40 kg / cm ² for 1 hour Sheet thickness after molding: 1.6 mm Resin content: 40%

[Physical Property Test Conditions] Glass transition temperature: Measured by a DMA method after performing an etching treatment and removing a copper foil. Heating speed 3 ° C / min Peel strength: Conforms to JIS K 6481. Delamination strength: Conforms to JIS K 6486.

[0038]

[Table 2]

[0039]

According to the present invention, the heat resistance of the cured product is remarkably improved, and at the same time, the adhesiveness to metal and other inorganic materials and the adhesiveness between the cured products are excellent. It is possible to provide an epoxy resin composition having excellent solder crack resistance during mounting, and excellent heat resistance and adhesion to a substrate and a copper foil in a printed wiring laminate.

Therefore, the epoxy resin composition of the present invention can be widely and effectively used for semiconductor encapsulants, printed wiring board materials, resist inks, advanced composite materials, and the like.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 CD051 CD061 EJ016 EU186 FD019 FD146 FD157 FD208 GF00 GH01 GJ01 4J036 AA01 AD08 AF06 DA01 DA02 DA04 DB05 DC45 FA01 JA01 JA06 JA07 JA08

Claims (9)

[Claims] 1. An epoxy resin composition comprising an epoxy resin (A) and a curing agent (B) as essential components, wherein the curing agent (B) is a hydroxyl-substituted aromatic compound represented by the following formula 1. (R is independently a hydrogen atom or a carbon atom having 1 to 1
(6) an epoxy resin composition having a structure knotted by a group represented by: 2. The curing agent (B) comprises a hydroxyl-substituted aromatic compound represented by the following formula 2: The composition according to claim 1, which has a structure knotted by a group represented by the formula: 3. The curing agent (B) is represented by the following formula 3 The composition according to claim 2, wherein X is independently a hydrogen atom, a methyl group, an ethyl group, a propyl group or a t-butyl group, and n is an integer of 1 to 4. 4. The composition according to claim 3, wherein the curing agent (B) is obtained by reacting cyanuric chloride with aminophenol. 5. The composition according to claim 1, wherein the epoxy resin (A) is a bisphenol-type epoxy resin or a novolak-type epoxy resin. 6. The composition according to claim 1, further comprising an inorganic filler (C) in addition to the epoxy resin (A) and the curing agent (B). 7. The composition according to claim 6, further comprising a curing accelerator in addition to the epoxy resin (A), the curing agent (B) and the inorganic filler (C). 8. The composition according to claim 1, further comprising an organic solvent (D) in addition to the epoxy resin (A) and the curing agent (B). 9. The composition according to claim 8, further comprising a curing accelerator in addition to the epoxy resin (A), the curing agent (B) and the organic solvent (D).