JP2002003570A - Epoxy resin and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin having a narrow molecular weight distribution and excellent in fluidity and thermostability, and to provide its production method. SOLUTION: This epoxy resin is obtained by reacting a hydroxynaphthalene compound and an aromatic aldehyde compound in the presence of an alkaline catalyst and thereafter, carrying out epoxdation with epichlorohydrin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin having a narrow molecular weight distribution and a method for producing the same, and provides an epoxy resin having excellent fluidity and heat resistance as a resin for electronic materials and a resin for molding materials. .

[0002]

2. Description of the Related Art It has been known that hydroxynaphthalene resins can be obtained by reacting hydroxynaphthalenes and aldehydes in the presence of an acid catalyst, and naphthol is commonly used as hydroxynaphthalenes. I have. For example, Japanese Patent Publication No. 08-26111, entitled "Method of Manufacturing Thermosetting Resin Composition and Condensed Polycyclic Aromatic Resin", discloses that a condensed polycyclic aromatic compound has an aromatic compound having at least one aldehyde group as a linking material. And a thermosetting resin composition obtained by heating in the presence of an acidic catalyst, and a method for producing the same.

However, such a naphthol resin obtained by reacting in the presence of an acidic catalyst has a wide molecular weight distribution, and has a high melt viscosity due to the inclusion of a high molecular weight component, making handling difficult. There is.

Although the use of such a naphthol resin as an epoxy resin raw material or an epoxy resin curing agent for resin encapsulation of a semiconductor chip has been studied, it has a wide molecular weight distribution and contains a high molecular weight component as described above. Therefore, there is a disadvantage that the viscosity becomes high and handling becomes difficult.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin for an electronic material and a resin for a molding material which exhibit excellent fluidity and heat resistance, and in particular, a molecular weight distribution which can be suitably used as a resin for a semiconductor encapsulant. To provide an epoxy resin having a narrow width and a method for producing the same.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, completed the present invention. That is, the present invention provides an epoxy resin containing 70% by weight or more of the epoxy resin represented by the formula (1) and containing 10% by weight or less of a component having a higher molecular weight than the formula (1).

Embedded image (Wherein m represents an integer of 1 to 2 and n represents an integer of 0 to 1). Further, a hydroxynaphthalene compound represented by the formula (3) and a hydroxynaphthalene compound represented by the formula (4) A method for producing an epoxy resin represented by the formula (1), characterized in that an aromatic aldehyde compound is reacted in the presence of a basic catalyst and then epoxidized with epichlorohydrin.

Embedded image (In the formula, m represents an integer of 1 to 2.)

Embedded image (In the formula, n represents an integer of 0 to 1.)

In the present invention, the component having a higher molecular weight than the formula (1) means an epoxy resin represented by the formula (5).

Embedded image (In the formula, x represents an integer of 2 or more.)

The epoxy resin represented by the formula (1) of the present invention is preferably contained in the resin in an amount of 70% by weight or more for the purpose of the present invention in that the molecular weight distribution is narrow, and particularly preferably 80% by weight or more. Preferred for low melt viscosity or heat resistance. The epoxy resin represented by the formula (1)
When the content is less than 0% by weight, the feature of the present invention, that is, a narrow molecular weight distribution, becomes insufficient, and other components necessarily increase. That is, the other component is a component having a higher molecular weight than the formula (1),
Or a monofunctional epoxy component.

According to the formula (1), when the component having a high molecular weight increases, the melt viscosity increases, and the fluidity is impaired. Further, when the monofunctional epoxy component is increased, heat resistance is impaired, and when it is used as a resin for a semiconductor encapsulant, it becomes a factor of inducing curability.

The content of the component having a higher molecular weight than the formula (1), that is, the epoxy resin represented by the formula (5) is preferably 10% by weight or less. When the epoxy resin represented by the formula (5) is more than 10% by weight, the molecular weight and the melt viscosity of the resin increase, and the fluidity is impaired.

When the epoxy resin represented by the formula (1) is a compound represented by the formula (2), that is, when the hydroxynaphthalene compound represented by the formula (3) is β-naphthol, The aromatic aldehyde compound represented by the formula (1) is a benzaldehyde, which is reacted in the presence of a basic catalyst and then epoxidized with epichlorohydrin. The features of the invention are more remarkably exhibited, and further excellent low melt viscosity and heat resistance can be obtained.

Next, the method for producing the epoxy resin of the present invention will be described. An aromatic aldehyde compound represented by the formula (4) is added to the hydroxynaphthalene compound represented by the formula (3), and a solvent is added as necessary. A basic catalyst is added to this system, and the mixture is heated and heated to react. After completion of the reaction, the basic catalyst is neutralized with an acid and washed and removed with water. The temperature is further increased, and water and unreacted monomers generated by the reaction in the system are removed by distillation to obtain a narrow molecular weight distribution hydroxynaphthalene resin. The epoxy resin of the present invention is obtained by reacting this resin with an excess of epichlorohydrin in the presence of an aqueous sodium hydroxide solution.

The hydroxynaphthalene compound represented by the formula (3) includes α-naphthol, β-naphthol,
1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,
Examples thereof include 3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene. These hydroxynaphthalene compounds may be used alone or in combination of two or more. Among these compounds, β-naphthol, which is particularly easy to obtain a narrow molecular weight distribution resin and is economically advantageous, is preferred.

As the aromatic aldehyde compound represented by the formula (4), benzaldehyde, salicylaldehyde,
Parahydroxybenzaldehyde and the like. These aromatic aldehyde compounds may be used alone or in combination of two or more. Among these compounds, particularly preferred is benzaldehyde, from which a narrow molecular weight distribution resin is easily obtained.

The number of moles of the aromatic aldehyde compound is preferably 0.5 to 1.5 moles per mole of the hydroxynaphthalene compound, and more preferably 0.8 to 1.0 moles. Ratios are preferred. When the number of moles of the aromatic aldehyde compound relative to the number of moles of the hydroxynaphthalene compound is less than 0.5, a large amount of unreacted hydroxynaphthalene compound remains, and a long distillation step is required to remove this, and This is economically disadvantageous because the yield decreases. When the number of moles of the aromatic aldehyde compound exceeds 1.5 with respect to the number of moles of the hydroxynaphthalene compound, unreacted aromatic aldehyde compound remains, and a long distillation step is required to remove the unreacted aromatic aldehyde compound. Is economically disadvantageous.

A solvent is added to the hydroxynaphthalene compound and the aromatic aldehyde compound in the above proportions, if necessary. Generally, a hydroxynaphthalene compound is solid at room temperature, and it is therefore desirable to make the reaction system uniform by adding a solvent. In particular, when the aromatic aldehyde compound is parahydroxybenzaldehyde which is solid at room temperature, it is preferable to add a solvent. As the solvent used in the present invention, a solvent inert to the reaction is used, and specific examples thereof include alcohols such as butanol and octanol, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and water. Among these solvents, water, which is easily available and economically advantageous, is preferred. The amount of the solvent used is preferably in the range of 100 parts by weight or less based on the hydroxynaphthalene compound. If the amount exceeds 100 parts by weight, it takes a long time to remove the solvent, and the amount of waste increases, which is economically disadvantageous.

The system of the hydroxynaphthalene compound, the aromatic aldehyde compound and the solvent is heated and heated, and when the temperature in the system reaches 60 to 80 ° C., a basic catalyst is added. If the temperature in the system is lower than 60 ° C., the hydroxynaphthalene compound and the aromatic aldehyde compound may not be completely dissolved, which is not preferable. On the other hand, when the temperature in the system exceeds 80 ° C., the reaction rapidly proceeds, and there is a risk of bumping, which is not preferable. Examples of the basic catalyst used in the present invention include aqueous solutions of inorganic bases such as sodium hydroxide, barium hydroxide and calcium hydroxide, and strong organic bases such as 1,8-diazabicyclo [5,4,0] undecene-7. Can be Among these basic catalysts, an aqueous solution of sodium hydroxide, 1,8-diazabicyclo [5,4,0] undecene-7, which is particularly easy to obtain a narrow molecular weight distribution resin, is preferable.

The amount of the basic catalyst used ranges from 0.2 mol to 0.8 mol, preferably from 0.3 mol to 0.6 mol, per 1 mol of the hydroxynaphthalene compound. When the amount of the basic catalyst used is less than 0.2 mol per 1 mol of the hydroxynaphthalene compound, the reactivity is poor and many unreacted monomers remain. The basic catalyst is used in an amount of 0.1 to 1 mol of the hydroxynaphthalene compound.
If it exceeds 8 moles, there is no problem in the reaction, but it takes a long time in the catalyst removing step, and the amount of catalyst to be discarded increases, which is economically disadvantageous.

If an acidic catalyst is used, a resin having a wide molecular weight distribution can be generally obtained, but a resin having a narrow molecular weight distribution may be obtained depending on the reaction conditions. However, in this case, a xanthene structure in which the hydroxyl groups represented by the formula (6) are condensed is formed, and the hydroxyl groups are lost.

Embedded image

After adding the basic catalyst, the inside of the system is heated and heated to react at 100 to 120 ° C. for 3 to 20 hours. When the reaction temperature is lower than 100 ° C., the progress of the reaction is slowed, and the amount of the unreacted monomer remaining is undesirably increased. Further, the reaction temperature does not exceed 120 ° C. due to reflux of the solvent or the condensed water generated by the reaction.

After completion of the reaction, the basic catalyst is neutralized with an acid and washed and removed with water. The acid used in the present invention is not particularly limited as long as it can generate a basic catalyst and a neutralized salt, but an organic acid that does not cause ionic impurities in the resin is preferable, and acetic acid is particularly preferable. Used for The amount of the acid used is preferably equivalent to the basic catalyst.

The method of washing with water is not particularly limited as long as it can be separated into an organic layer containing a resin and an aqueous layer containing a neutralizing salt, and then the aqueous layer can be removed outside the system. It is efficient and preferable to dissolve the resin layer with the above organic solvent and separate it from the aqueous layer.

After washing, unreacted hydroxynaphthalene compound and aromatic aldehyde compound are distilled off. The method of distillation is preferably a general method of distillation under reduced pressure, and furthermore, a method of azeotropic removal by blowing steam into the system. The temperature in the system is preferably 150 ° C. or higher. When the temperature is lower than 150 ° C., unreacted hydroxynaphthalene compound and aromatic aldehyde compound are not sufficiently removed and remain in the resin.

Next, the obtained resin is epoxidized by a conventional method. That is, epichlorohydrin is added to the obtained resin in an amount of 2 to 10 times by weight, a solvent such as isopropyl alcohol is appropriately added as needed, and then an aqueous solution of sodium hydroxide is added to epichlorohydrin at 20 to 50 ° C.
1-0.5 mol is added. After the reaction at 50 to 80 ° C, the reaction product is washed with a large excess of water to remove by-product salts and excess sodium hydroxide, and the excess epichlorohydrin is distilled off under reduced pressure.

As described above, the epoxy resin of the present invention can be obtained. The composition (% by weight) of the obtained epoxy resin was analyzed using a GPC column (G1000HXL:
One, (G2000HXL: two, G3000HXL:
1), the flow rate was 1.0 ml / min, the elution solvent was tetrahydrofuran, and the column temperature was 40 ° C.

[0026]

The present invention will be described below with reference to examples. The present invention is not limited by these examples.
Further, “parts” and “%” described in Production Examples, Examples and Comparative Examples are all “parts by weight” and “% by weight”.
Is shown.

Production Example 1 β-β was added to a reactor equipped with a stirrer, a reflux condenser and a thermometer.
Naphthol 100 parts, benzaldehyde 59 parts, water 25
When the temperature in the system reaches 70 ° C.
30 parts of a 50% aqueous sodium hydroxide solution was gradually added.
Thereafter, the temperature was further raised, and the temperature in the system was kept at 110 ° C. to cause a reaction for 3 hours. Next, 22 parts of acetic acid was added to neutralize, 100 parts of methyl isobutyl ketone and 120 parts of water were added, and the mixture was stirred for 10 minutes. After removing the aqueous layer outside the system, water and methyl isobutyl ketone were distilled off while heating the inside of the system to 150 ° C. Further, while maintaining the temperature in the system at 150 ° C., 500 ml of steam is
/ Hour was blown into the system for 2 hours to remove unreacted β-naphthol. The obtained resin was taken out of the reactor to obtain 51 parts of a resin having a viscosity of 0.1 Pa · s (200 ° C.). GPC measurement of this resin showed that the peak corresponding to the hydroxynaphthalene resin represented by the formula (2) was 8
0% and the higher molecular weight component was 1%.

Preparation Example 2 100 parts of β-naphthol in 100 parts of 2,6-dihydroxynaphthalene, 59 parts of benzaldehyde in 61 parts of salicylaldehyde, and 30 parts of a 50% by weight aqueous sodium hydroxide solution in 1,8-diazabicyclo [5 , 4,0] undecene-7, and 49 parts of a resin having a viscosity of 0.2 Pa · s (200 ° C.) was obtained in the same manner as in Production Example 1 except that 38 parts were used. GPC measurement of this resin showed a peak corresponding to the hydroxynaphthalene resin represented by the formula (1) of 7
5% and higher molecular weight components were 2%.

Production Example 3 100 parts of α-naphthol were placed in the same reactor as in Production Example 1,
59 parts of benzaldehyde, 25 parts of water and 5 parts of p-toluenesulfonic acid were charged, and the temperature was raised to 100 ° C.
And reacted for 3 hours. Next, 100 parts of methyl isobutyl ketone and 120 parts of water were added, and the mixture was stirred for 10 minutes, and then allowed to stand to separate an organic layer and an aqueous layer. After removing the water layer out of the system, water, methyl isobutyl ketone and unreacted monomer were distilled off while heating the system to 200 ° C., and 50 parts of a resin having a viscosity of 1.1 Pa · s (200 ° C.) I got GPC measurement of this resin showed that the peak corresponding to the hydroxynaphthalene resin represented by the formula (1) was 36%,
And the component having a higher molecular weight than this was 57%.

Example 1 In a reactor equipped with a stirrer, a reflux condenser and a thermometer, 100 parts of the resin obtained in Production Example 1 and epichlorohydrin 28 were added.
0 parts, and 100 parts of isopropyl alcohol,
After stirring and dissolving, the temperature in the system is maintained at 35 ° C.
56 parts by weight of an aqueous sodium hydroxide solution were added over 1 hour. During that time, the temperature in the system was gradually increased to 65 ° C. at the end of the addition. After reacting for 1 hour while maintaining the temperature in the system at 65 ° C., 350 parts of water was added and washed with water to remove by-product salts and excess sodium hydroxide. Next, excess epichlorohydrin and isopropyl alcohol were distilled off under reduced pressure to obtain 125 parts of an epoxy resin having an epoxy equivalent of 245 g / eq.

Example 2 134 parts of an epoxy resin having an epoxy equivalent of 202 g / eq in the same manner as in Production Example 1 except that 100 parts of the resin obtained in Production Example 1 was changed to 100 parts of the resin obtained in Production Example 2. I got

COMPARATIVE EXAMPLE In the same manner as in Production Example 1 except that 100 parts of the resin obtained in Production Example 1 was changed to 100 parts of the resin obtained in Production Example 3, 118 parts of an epoxy resin having an epoxy equivalent of 236 g / eq was used. Obtained.

Application Examples 1 and 2 and Comparative Application Example Each of the epoxy resins obtained in Examples 1 and 2 and Comparative Example 1 was used, and phenol / p-xylylene glycol diethyl ether polycondensate (PR from Sumitomo Durez) was used as a curing agent. −
54443), triphenylphosphine, fused silica, and stearic acid were roll-kneaded at the compounding amounts (parts) in Table 1 to obtain a molding material. 100 kg / cm ^{2 of} this molding material,
Molded at 175 ° C for 10 minutes, and then
Post-curing was performed under the conditions of time to obtain a cured molded product. Table 1 shows the results of measuring the spiral flow of the molding material before molding, and the glass transition temperature, bending strength, and flexural modulus of the cured molded product.

[0034]

[Table 1]

(Measurement and Evaluation Methods) Spiral flow: using a mold for measuring spiral flow according to EMMI-I-66, mold temperature 175
C., injection pressure 70 kg / cm ² , and curing time 2 minutes. 2. Glass transition temperature: measured using a thermomechanical analyzer (TMA). 3. Flexural strength and flexural modulus: measured according to JIS K6911.

[0036]

As is clear from Table 1, the epoxy resin composition using the epoxy resin of the present invention has excellent fluidity, and has improved flexural strength while maintaining flexural modulus. It can be seen that the composition had excellent heat resistance. For this reason, the epoxy resin of the present invention is particularly suitable for an epoxy resin sealing material for high-performance electronic components. Further, it is suitable for epoxy resin powder coatings, epoxy resin laminates, and the like, and is expected to contribute to improving the performance of electronic components.

Claims (6)

[Claims] 1. An epoxy resin represented by the formula (1)
An epoxy resin containing not less than 10% by weight and containing 10% by weight or less of a component having a higher molecular weight than the formula (1). Embedded image (In the formula, m represents an integer of 1 to 2, and n represents an integer of 0 to 1.) 2. The epoxy resin according to claim 1, wherein the epoxy resin represented by the formula (1) is a compound represented by the formula (2). Embedded image 3. A method comprising reacting a hydroxynaphthalene compound represented by the formula (3) with an aromatic aldehyde compound represented by the formula (4) in the presence of a basic catalyst, followed by epoxidation with epichlorohydrin. The method for producing an epoxy resin according to claim 1, wherein: Embedded image (In the formula, m represents an integer of 1 to 2.) (In the formula, n represents an integer of 0 to 1.) 4. The hydroxynaphthalene compound represented by the formula (3) is β-naphthol, and the aromatic aldehyde compound represented by the formula (4) is benzaldehyde.
The method for producing the epoxy resin described in the above. 5. The basic catalyst is an aqueous sodium hydroxide solution,
5. The method for producing an epoxy resin according to claim 3, wherein the method is 1,8-diazabicyclo [5,4,0] undecene-7. 6. The method for producing an epoxy resin according to claim 3, wherein the number of moles of the basic catalyst is at least 0.2 mol and at most 0.8 mol per 1 mol of the hydroxynaphthalene compound.