JPH05117364A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide a heat-resistant and low hygroscopic epoxy resin composition essentially composed of an addition compound synthesized from a specified bisphenol and a bifunctional epoxy resin and a curing agent for epoxy resins and useful as a material for a laminate. CONSTITUTION:An objective composition containing, as the essential components, (A) an addition compound synthesized by reacting (i) bisphenols composed of bisphenol A, bisphenol F and/or tetrabromobisphenol A with (ii) a bifunctional epoxy resin such as diglycidyl ether of 1,1-bisphenol-1-phenylethane of the formula (R1 to R4 are H, 1-6C alkyl, 6-18C aryl or halogen) and (B) a curing agent such as dicyandiamide.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an epoxy resin composition which is particularly useful as a laminate material.

[0002]

2. Description of the Related Art Conventionally, a combination of a bisphenol type epoxy resin and dicyandiamide has been mainly used as a material for an industrial printed wiring board. recent years,
Along with surface mounting, high density mounting, and multilayered printed wiring boards, improved heat resistance of the boards and low water absorption have been demanded. Conventionally, for such purpose, a method has been adopted in which a polyfunctional novolac epoxy resin is used in combination with a bisphenol epoxy resin as a heat resistance imparting component.

[0003]

When a novolac type epoxy resin is added to a bisphenol type epoxy resin for the purpose of improving heat resistance and low water absorption, heat resistance and water absorption are improved by increasing the addition amount. It is not always sufficient depending on the application. Further, if the addition amount is further increased, the toughness of the cured product decreases and becomes brittle, so the adhesiveness with the metal foil forming the circuit deteriorates, and the high viscosity causes adverse effects such as deterioration of the formability. Come out. The purpose of the present invention is to
It is intended to obtain an epoxy resin composition for a laminated board, which has improved heat resistance and low hygroscopicity.

[0004]

The present invention comprises at least one bisphenol (a-1) selected from the group consisting of bisphenol A, bisphenol F and tetrabromobisphenol A;

[0005]

[Chemical 3] (In the formula, each of R _{1 to} R ₄ independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 18 carbon atoms, or halogen.) A first invention relating to an epoxy resin composition comprising an adduct obtained by previously reacting with an epoxy resin (a-2) and an epoxy curing agent, and the bisphenols ((a-1) component) ), A bifunctional epoxy resin ((a-
The second invention relates to an epoxy resin composition containing, as an essential component, an adduct obtained by previously reacting (2) component) and a polyfunctional epoxy resin (a-3), and an epoxy curing agent.

Specific examples of the difunctional epoxy resin (component (a-2)) used in the present invention include R ₁ to
R ₄ is an alkyl group or aryl group (including each isomer) represented by methyl, ethyl, propyl, butyl, amyl, hexyl or phenyl, or a halogen atom represented by a chlorine atom or a bromine atom.

The bifunctional epoxy resin used in the present invention can be obtained, for example, by condensing a phenol with an aromatic aldehyde or an aromatic ketone under an acidic catalyst, and converting it into a glycidyl ether with an epihalohydrin such as epichlorohydrin.

Examples of phenols include phenol,
Cresol, ethylphenol, propylphenol,
Butylphenol, amylphenol, hexylphenol, xylenol, methylbutylphenol, phenylphenol and the like.

Examples of aromatic aldehydes or aromatic ketones are benzaldehyde, tolualdehyde, dimethylbenzaldehyde, acetophenone, methylacetophenone, trimethylacetophenone, ethylphenylketone, butylphenylketone and hexylphenylketone.

The reaction of phenols with aromatic aldehydes or aromatic ketones can be carried out under an inorganic acid such as hydrogen chloride or sulfuric acid, an organic acid such as acetic acid, p-toluenesulfonic acid or thioglycolic acid, or an acidic catalyst such as Lewis acid. A known method in which an aromatic ketone or an aromatic aldehyde is condensed with a phenol in an amount of at least 2 times the molar amount, followed by washing with water, distilling off unreacted phenols, and in some cases post-treatment such as recrystallization with a poor solvent. Can be done at.

For the purpose of imparting flame retardancy, it is also possible to use a phenol, aromatic aldehyde or aromatic ketone in which the aromatic ring is chlorinated or brominated.

In order to glycidyl etherify the condensate of the above-mentioned phenols and aromatic aldehyde or aromatic ketone, a conventionally known method of reacting the condensate with epihalohydrin in the presence of an alkali such as caustic soda is used. it can. In particular, when a high-purity product is to be obtained, JP-A-60 is used.
As described in JP-A-31517, the reaction under an aprotic solvent is preferable.

As the epoxy curing agent used in the present invention, known ones can be used, and examples thereof include polyphenols such as phenol novolac, cresol novolac and 1,1,1-trishydroxyphenylethane.
Examples include amine-based curing agents such as aromatic amines and aliphatic amines, acid anhydrides, dicyandiamide, and hydrazide compounds. Preferred are dicyandiamide and polyhydric phenols. Further, the compounding amount of these epoxy curing agents is preferably 0.3 to 1.2 equivalents based on the epoxy group.

Further, to the extent that the effects of the present invention are not impaired,
It is also possible to use a conventionally known bifunctional epoxy resin together. Specific examples thereof include glycidyl ether compounds of bisphenol A and glycidyl ether compounds of various bisphenols such as tetrabromobisphenol A glycidyl ether compounds. As a method of combined use, the components (a-1) and (a-2) can be used by pre-reacting, or the components (a-1) and (a-
It can also be used as a mixture with a preliminary reaction product with the component 2). Among them, the method of preliminarily reacting with the former components (a-1) and (a-2) is used.

The polyfunctional epoxy resin used in the second invention is a novolac type epoxy resin such as glycidyl ether of phenol novolac or glycidyl ether of cresol novolak, phenols and acrolein, crotonaldehyde, glyoxal, isopropenylphenyl. Glycidyl etherification products of polycondensates with aldehydes, etc.

[0016]

[Chemical 4] (In the formula, R _{5 to} R ₉ are each independently hydrogen and a carbon number of 1 to
6 is an alkyl group or an alkoxy group, X independently represents hydrogen, chlorine or bromine, and n is the average number of repeating units and is a number of 1 to 6. ), And a polyfunctional epoxy resin represented by the above chemical formula 4 is preferable. In addition, the compound represented by the above chemical formula 4 is the following chemical formula 5,

[0017]

[Chemical 5] (In the formula, R _{5 to} R ₉ and X are the same as those in Chemical Formula 4 above.) And the following Chemical Formula 6

[0018]

[Chemical 6] (In the formula, R _{5 to} R ₉ and X are the same as those in the above chemical formula 4.) A compound in which the bonding units represented by the formula are mixed or present in one molecule, and in one molecule Is a so-called polydisperse type oligomer having a distribution in the number of these bonding units. The above n represents the number of repeating units as an average value of these. When n exceeds 6, the viscosity of the composition becomes too high, and the impregnation property into glass cloth becomes high, which is not preferable.

Specific examples of R _{5 to} R ₉ in the structure of the polyfunctional epoxy resin represented by the above chemical formula 4 are methyl, ethyl, propyl, butyl, amyl, hexyl (including each isomer), methoxy, Examples include ethoxy or butoxy groups.

The polyfunctional epoxy resin represented by the above chemical formula 4 is obtained by condensing, for example, phenols and aldehydes or ketones containing a phenolic hydroxyl group under an acidic catalyst and converting them into glycidyl ether with epichlorohydrin or the like. can get. Examples of phenols are:
Examples include phenol, cresol, ethylphenol, propylphenol, butylphenol, amylphenol, hexylphenol, xylenol, and methylbutylphenol. These phenols can be used alone or in combination.

Examples of aldehydes or ketones containing a phenolic hydroxyl group include hydroxybenzaldehyde, methylhydroxybenzaldehyde, dimethylhydroxybenzaldehyde, vanillin, hydroxyacetophenone, methylhydroxyacetophenone, dimethylhydroxyacetophenone, hydroxyphenylethylketone and hydroxyphenylbutyl. Examples include ketones and hydroxyphenylhexyl ketones.

The reaction between phenols and aldehydes or ketones containing a phenolic hydroxyl group is carried out by inorganic acids such as hydrogen chloride and sulfuric acid, acetic acid, p-toluenesulfonic acid,
It can be carried out by a well-known method in which post-treatments such as condensation under an organic catalyst such as thioglycolic acid and an acidic catalyst such as Lewis acid, washing with water, and distillation of unreacted phenols are carried out.

For the purpose of imparting flame retardancy, it is also possible to use chlorinated or brominated aromatic rings of the above-mentioned phenols and aldehydes or ketones containing a phenolic hydroxyl group.

Further, in order to glycidyl etherify the condensation product of the above-mentioned phenols and aldehydes or ketones containing a phenolic hydroxyl group, the phenols and epihalohydrin such as epichlorohydrin are added in the presence of an alkali such as caustic soda. A conventionally known method of reacting can be used. In particular, when a high-purity product is to be obtained, JP-A-60 is used.
As described in JP-A-31517, the reaction under an aprotic solvent is preferable.

The reaction between the bisphenols and the bifunctional epoxy resin and the reaction between the bisphenols and the bifunctional epoxy resin and the polyfunctional epoxy resin can be carried out by known methods. For example, each of these components may be mixed and allowed to react in the presence of a basic catalyst such as triphenylphosphine or imidazole.

In the present invention, known additives such as a curing accelerator, a flame retardant, a release agent, a surface treatment agent and a filler may be added to the composition depending on the purpose. Imidazoles and tertiary amines as curing accelerators, antimony trioxide, red phosphorus, etc. as flame retardants, waxes, zinc stearate, etc. as mold release agents, and silane coupling as surface treatment agents. An agent can be mentioned. Examples of the filler include silica, alumina, talc, clay, glass fiber and the like.

When the resin composition of the present invention is used in a laminated board, the resin composition is uniformly dissolved in a solvent such as methyl ethyl ketone, ethylene glycol monomethyl ether, dimethylformamide, etc. to prepare glass fiber, polyester fiber, polyamide fiber. A prepreg obtained by impregnating a base material made of woven cloth, mat, paper or a combination thereof made of organic or inorganic fiber such as alumina fiber, and heating and drying may be hot press molded.

[0028]

Industrial Applicability The resin composition of the present invention provides a well-balanced cured molded article which is excellent in heat resistance and low hygroscopicity.

[0029]

[Examples] The evaluation of cured moldings is as follows. -Glass transition temperature: Measured using a dynamic viscoelasticity measuring device (Rheograph Solid, manufactured by Toyo Seiki Co., Ltd.). Water absorption (measure of hygroscopicity): Using a high-pressure steam environment tester (manufactured by Hirayama Seisakusho Co., Ltd., PC-305S), weight change was measured at 100 ° C.

Reference Example 1 1,1-bisphenol-1-phenylethane 9 obtained in the same manner as in Example 1 of JP-A-60-48941
7.3 g (0.7 mol of phenolic hydroxyl group) was charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a condenser with a separating tube, and epichlorohydrin 453.3.
g, and dissolved in 226.7 g of dimethyl sulfoxide. While maintaining the reaction system at 41 torr, at a temperature of 48 ° C, 4
57.6 g of an 8.6% aqueous sodium hydroxide solution was continuously added dropwise over 5 hours. During this period, while maintaining the temperature at 48 ° C., the azeotropically distilled epichlorohydrin and water were cooled and liquefied, and the reaction was performed while returning the organic layer to the reaction system. After completion of the reaction, unreacted epichlorohydrin was removed by concentration under reduced pressure, a diglycidyl ether containing a by-product salt and dimethylsulfoxide was dissolved in methylisobutylton, and the by-product salt and dimethylsulfoxide were washed with water. The epoxy equivalent of the diglycidyl ether thus obtained was 212 g.
/ Equivalent.

Reference Example 2 p-hydroxybenzaldehyde 183.2 g, 2-butyl-5-methylphenol 341.8 g, m-cresol 75.0 g, p-toluenesulfonic acid 0.50 g,
420 g of toluene was charged into a reaction vessel equipped with a thermometer and a condenser with a separation tube, and the temperature of the solution was raised to 10 ° C at 115 ° C.
Stir for hours. During this period, azeotropic toluene and water were cooled and liquefied, and the organic layer was allowed to react while being returned to the reaction system. After completion of the reaction, the solution was neutralized with a 10% aqueous sodium hydroxide solution and then concentrated under reduced pressure to obtain a reddish brown resin. Polyfunctional epoxy resin was obtained by glycidyl etherification in the same manner as in Reference Example 1 except that 92.4 g of the resin thus obtained was used. The epoxy equivalent was 205 g / equivalent, and the average number of repeating units n determined by GPC was about 2.

Reference Examples 3 to 8 Tetrabromobisphenol A was added as a bisphenol in a reaction vessel equipped with a thermometer, a stirrer and a condenser.
A glycidyl ether of bisphenol A as a bifunctional epoxy resin (Sumitomo Chemical Co., Ltd., trade name Sumiepoxy ELA-128, epoxy equivalent 188 g / equivalent) or the resin of Reference Example 1 as a multifunctional epoxy resin. The amount of each resin shown in Table 1 was charged, and further 9 g of methyl ethyl ketone was charged, and the resin was heated to 110 ° C.
After heating to completely dissolve it, 0.02 g of triphenylphosphine was added, and the mixture was reacted at 110 ° C. for 5 hours. Then, the solvent was removed by concentration under reduced pressure to obtain a resin. The analytical values (epoxy equivalent) of the obtained resin are shown in Table 1.

[0033]

[Table 1]

The ratios of the epoxy resins obtained in Examples 1 to 4 and Comparative Examples 1 and 2 and Reference Examples 3 to 8 to dicyandiamide and 2-ethyl-4-methylimidazole (abbreviated as imidazole) are shown in Table 2. And blended with a Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.).
Then, after press-molding at 160 ° C., post-curing was performed in a 160 ° C. oven for 1.5 hours to obtain a cured molded product. Table 2 shows the results of measuring the glass transition temperature and the water absorption of the obtained cured molded product.

Comparative Example 3 Sumiepoxy ESB-500 (trade name of brominated bisphenol A type epoxy resin, epoxy equivalent 472 g / equivalent, manufactured by Sumitomo Chemical Co., Ltd.) 90 g, Sumiepoxy ES
CN-220F (trade name of o-cresol novolac type epoxy resin, epoxy equivalent 215 g / equivalent, manufactured by Sumitomo Chemical Co., Ltd.) 10 g, dicyandiamide, and 2-ethyl-4-methylimidazole were added, and the same as Example 5. A cured molded product was obtained by various methods. The evaluation results are shown in Table 2.

[0036]

[Table 2]

Example 5 and Comparative Example 4 The epoxy resins obtained in Reference Examples 3 and 7 were mixed with dicyandiamide and 2-ethyl-4-methylimidazole in the proportions shown in Table 3 to give a resin solid content of 70 parts. To 30 parts of methyl ethyl ketone was added and dissolved to obtain a resin varnish. The varnish was applied to a glass cloth (Kanbo Co., Ltd. KS-1).
600, treated with epoxysilane) and dried in a hot air dryer at 180 ° C. for 8 minutes to 15 minutes to obtain a prepreg.
6 pieces of prepreg made of copper foil (Furukawa Circuit Wheel Co., Ltd.)
Made, TTAI treatment, 85μ thickness) are overlaid, 160 ℃
At 50 kg / cm ² under pressure for 90 minutes,
A 1 mm copper clad laminate was obtained. The results of measuring the physical properties of the laminate are shown in Table 3.

Comparative Example 5 Sumiepoxy ESB-500 (trade name of brominated bisphenol A type epoxy resin, epoxy equivalent 472 g / equivalent, Sumitomo Chemical Co., Ltd.) 90 g, Sumiepoxy ES
CN-220F (trade name of o-cresol novolac type epoxy resin, epoxy equivalent 215 g / equivalent, manufactured by Sumitomo Chemical Co., Ltd.) 10 g, dicyandiamide, and 2-ethyl-4-methylimidazole were added, and the same as Example 5. A laminated board was obtained by various methods. The evaluation results are shown in Table 3.

[0039]

[Table 3]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Kanagawa 6 Kitahara, Tsukuba, Ibaraki Sumitomo Chemical Co., Ltd.

Claims (3)

[Claims] 1. At least one bisphenol (a-1) selected from the group consisting of bisphenol A, bisphenol F and tetrabromobisphenol A, and a compound represented by the general formula 1 (In the formula, each of R _{1 to} R ₄ independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 18 carbon atoms, or halogen.) An epoxy resin composition comprising an adduct obtained by previously reacting with an epoxy resin (a-2) and an epoxy curing agent as essential components. 2. A bisphenol (a-1) according to claim 1,
An epoxy resin composition comprising an adduct obtained by previously reacting a bifunctional epoxy resin (a-2) and a polyfunctional epoxy resin (a-3) and an epoxy curing agent as essential components. 3. The polyfunctional epoxy resin (a-3) is represented by the general formula 2 (In the formula, R _{5 to} R ₉ are each independently hydrogen and a carbon number of 1 to
6 is an alkyl group or an alkoxy group, X is each independently hydrogen, chlorine or bromine, and n is the average number of repeating units and is a number of 1 to 6. The epoxy resin composition according to claim 2, which is a polyfunctional epoxy resin represented by the formula (4).