JPH04264117A - New high-performance resin, epoxy resin composition, and its cured article - Google Patents

Abstract

PURPOSE:To prepare a resin giving a resin compsn. which gives a cured article exhibiting a high heat resistance, a low water absorption, and excellent adhesive properties by condensing naphthol with p-xylylene glycol. CONSTITUTION:Naphthol (1- or 2-naphthol) is condensed with p-xylylene glycol in the presence of an acid catalyst (e.g. hydrochloric, sulfuric, oxalic, or p- toluenesulfonic acid) to give a resin of formula I, which is allowed to react with an epihalohydrin in the presence of a basic compd. to give a resin of formula II. By compounding an epoxy resin with the resin of formula I as a curative, by compounding the resin of formula II as an epoxy resin with a curative, or by compounding the resin of formula II as an epoxy resin with the resin of formula I as a curative, an epoxy resin compsn. is prepd. The compsn. gives a cured article exhibiting a high heat resistance, a low water absorption, and excellent adhesive properties and is used, e.g. for sealing electronic parts.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a resin useful as a material for sealing or laminating electronic components, a resin composition containing the resin that provides a cured product with high heat resistance, low water absorption, and high adhesiveness, and a cured product thereof. Regarding.

0002

BACKGROUND OF THE INVENTION Conventionally, resin compositions containing epoxy resins, phenol novolac resins, and curing accelerators as main components have been widely used in the field of sealants for electrical and electronic components, particularly ICs.

[0003] The recent increase in density and integration in ICs has led to
Encapsulants are now required to have high heat resistance, low water absorption, and high adhesion. In particular, the harsh conditions of immersion in a solder bath during high-density mounting of ICs require high heat resistance and
Demand for low water absorption and high adhesion is increasing.

0004

[Problems to be Solved by the Invention] However, the cresol novolak type epoxy resin that is generally used as the epoxy resin in conventional compositions is insufficient in terms of heat resistance against the harsh conditions of immersion in a solder bath. . In addition, JP-A-63-2003, which has been proposed as having heat resistance,
The polyepoxy compounds described in Japanese Patent No. 264622, which are obtained by epoxidizing polyphenols obtained by condensing aromatic aldehydes having phenolic hydroxyl groups with phenols, are not as good as cresol novolac type epoxy resins in terms of water absorption and adhesiveness. On the other hand, phenol novolac resins commonly used as curing agents are still insufficient in terms of heat resistance and water absorption.

[0005] The present invention provides a resin composition that can withstand these increasingly severe conditions, has high heat resistance, low water absorption, and provides a cured product with good adhesive properties, as well as resins and cured products that are components thereof. This is what we provide.

[0006]

[Means for Solving the Problems] As a result of intensive studies aimed at developing a resin composition that has the above-mentioned three contradictory properties: high heat resistance, low water absorption, and high adhesiveness, the present inventors found that
The present inventors have discovered that a resin capable of achieving the objective can be obtained by condensing naphthol and xylylene glycol, and have completed the present invention.

That is, the present invention provides formula (1)

000
8]

A resin represented by the formula (where n is 0 to 15).

(2) Equation (2)

[0011]

An epoxy resin represented by the formula (where n is 0 to 15).

(3) An epoxy resin composition comprising (A) an epoxy resin and (B) the resin described in (1) above as a curing agent.

(4) (A) The above (
2) An epoxy resin composition comprising the epoxy resin described above and (B) a curing agent.

(5) (A) The above (as epoxy resin)
2) An epoxy resin composition comprising the epoxy resin described in (B) and the resin described in (1) above as a curing agent.

(6) Contains a curing accelerator, (3) above, (
4) or the epoxy resin composition described in (5).

(7) The above (3), (4), (5) or (
6) A cured product of the epoxy resin composition according to item 6). It is related to.

The present invention will be explained in detail below. Formula (1)
The number of n is 0 to 15, and the average value of n is 2 to 10.
The number is preferably 3 to 7, more preferably 3 to 7. If the average value of n is too high, the viscosity will increase and workability will be impaired.

The resin of the present invention can be produced as follows. That is, it can be produced by dehydrating and condensing naphthol (1-naphthol or 2-naphthol) and p-xylylene glycol in the presence of an acid catalyst. In addition, 1-naphthol is preferable in order to set n to the above-mentioned preferable range. As the acid catalyst, hydrochloric acid, sulfuric acid, phosphoric acid, oxalic acid, p-toluenesulfonic acid, etc. can be used, and it is preferable to use 0.1 to 30% by weight of p-xylylene glycol as the acid catalyst. Moreover, it is preferable to use naphthol in an amount of 0.5 to 4.0 moles relative to p-xylylene glycol.

The reaction can be carried out without a solvent or in a solvent such as benzene, toluene or methyl isobutyl ketone. The reaction temperature is preferably in the range of 20 to 150°C. After the reaction is completed, the used catalyst is removed by washing with water or the like, and the solvent and excess naphthol are removed under reduced pressure to obtain the desired resin represented by formula (1).

Next, by reacting the thus obtained resin with an epihalohydrin compound in the presence of a basic compound, the epoxy resin represented by formula (2) can be easily obtained. Specific examples of the epihalohydrin compound include epichlorohydrin, epibromohydrin, epiiodohydrin, etc., and mixtures thereof can also be used, but epichlorohydrin is preferably used industrially.

The reaction between the epoxy resin represented by formula (2) and the epihalohydrin compound can be carried out by a known method. For example, a resin represented by formula (1) and an epihalohydrin compound in an excess molar amount relative to its hydroxyl equivalent are combined with a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, triethylammonium chloride, or hydroxylated. The reaction is carried out in the presence of an alkali metal hydroxide such as sodium or potassium hydroxide.

When a quaternary ammonium salt is used, the reaction stops at the stage of the ring-opening addition reaction, so the alkali metal hydroxide is then added to carry out the ring-closing reaction. Further, when the alkali metal hydroxide is added from the beginning and the reaction is carried out, the ring-opening addition reaction and the ring-closing addition reaction can be carried out at once.

The usage ratio of the epihalohydrin compound is usually 1 to 1 to 1 hydroxyl equivalent of the resin represented by formula (1).
50 moles, preferably in the range of 3 to 15 moles.
In addition, at this time, in order to carry out the reaction smoothly, alcohols such as methanol, or acetone, or aprotic polar solvents such as dimethyl sulfoxide, dimethyl sulfone, and dimethyl formamide can be used, and dimethyl sulfoxide is particularly preferred. is preferred.

The amount of alkali metal hydroxide used is determined by the formula (1
) is usually 0.8 to 1 per hydroxyl equivalent of the resin.
1.5 mol, preferably in the range of 0.9 to 1.3 mol, and when using a quaternary ammonium salt, the amount used is based on 1 hydroxyl equivalent of the resin represented by formula (1). Usually 0.001 to 1.0 mol, preferably 0.005 to 0.0 mol.
It is in the range of 5 moles. The reaction temperature is usually 30-130℃,
Preferably it is 40-120°C.

[0026] The reaction can also be allowed to proceed while removing water produced in the reaction from the reaction system. After the reaction is complete, the by-product salt is removed by washing with water, filtration, etc. to obtain the formula (
An epoxy resin represented by 2) is obtained. In the epoxy resin composition described in (4) or (5) above, the epoxy resin represented by formula (2) of the present invention can be used alone or in combination with other epoxy resins. When used together, the proportion of the epoxy resin of the present invention in the total epoxy resin is preferably 30% by weight or more, particularly preferably 50% by weight or more.

Other epoxy resins used in combination with the epoxy resin represented by formula (2) of the present invention include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, and alicyclic epoxy resin. , biphenyl type epoxy resins, etc. can also be used, but novolac type epoxy resins are particularly advantageous in terms of heat resistance.

Examples include, but are not limited to, cresol novolac type epoxy resins, phenol novolac type epoxy resins, and brominated phenol novolac type epoxy resins. These may be used alone or in combination of two or more.

In the epoxy resin compositions (3) and (5) above, the resin represented by formula (1) of the present invention can be used alone or in combination with other curing agents. When used together, the proportion of the resin of the present invention in the total curing agent is preferably 30% by weight or more, particularly preferably 50% by weight or more.

Other curing agents used in combination with the resin represented by formula (1) of the present invention include, for example, aliphatic polyamines,
Polyamine curing agents such as aromatic polyamines and polyamide polyamines, acid anhydride curing agents such as hexahydrophthalic anhydride and methyltetrahydrophthalic anhydride, phenolic curing agents such as phenol novolak and cresol novolak, boron trifluoride, etc. Lewis acids or their salts,
Examples include curing agents such as dicyanamides, but are not limited thereto. These may be used alone or in combination of two or more.

In the epoxy resin composition (3) above, the epoxy resin (A) includes, in addition to the epoxy resin represented by formula (2) of the present invention, the other epoxy resins mentioned above.

In the epoxy resin composition (4), examples of the curing agent (B) include the resin represented by formula (1) of the present invention as well as the other curing agents mentioned above.

In the epoxy resin composition of the present invention, (
B) The amount of the curing agent used is preferably 0.5 to 1.5 equivalents per equivalent of the epoxy group of the epoxy resin (A), particularly 0.
．． 6 to 1.2 equivalents are preferred.

As curing accelerators, imidazole compounds such as 2-methylimidazole and 2-ethylimidazole, and tertiary compounds such as 2-(dimethylaminomethyl)phenol are used.
Various known curing accelerators can be used, including amine compounds, triphenylphosphine compounds, etc., and are not particularly limited. The amount of the curing accelerator used is preferably in the range of 0.01 to 15 parts by weight, particularly preferably in the range of 0.1 to 10 parts by weight, based on 100 parts by weight of the epoxy resin (A).

[0035] The epoxy resin composition of the present invention may further contain known additives as required. Examples of additives include inorganic fillers such as silica, alumina, talc, and glass fiber; Examples include surface treatment agents for fillers such as silane coupling agents, mold release agents, and pigments.

The epoxy resin composition of the present invention can be obtained by uniformly mixing each component. Further, the epoxy resin composition of the present invention is usually precured at a temperature of 130 to 170°C for 30 to 300 seconds, and further cured for 150 to 200 seconds.
By post-curing at a temperature of 00°C for 2 to 8 hours, a sufficient curing reaction proceeds and the cured product of the present invention is obtained.
The cured product thus obtained has excellent performance, having three properties: low water absorption, and high adhesiveness while maintaining heat resistance.

Therefore, the resin of the present invention can be used as an epoxy resin or as a curing agent in a wide range of fields where heat resistance, low water absorption, and high adhesiveness are required. Specifically, it is useful as a compounding component of all electrical and electronic materials such as insulating materials, laminates, and sealing materials. Moreover, it can be used in fields such as molding materials and composite materials.

By using the epoxy resin represented by formula (2) and the resin represented by formula (1) of the present invention as both the epoxy resin component and the curing agent component, the effect becomes more pronounced. Furthermore, the resin of the present invention has a low softening point despite having a naphthol ring, so conventional techniques such as transfer molding can be used, and workability is good.

[0039]

[Examples] The present invention will be explained below with reference to Examples. Example 1 p-xylylene glycol 138g (1.0 mol), 1
- 288 g (2.0 moles) of naphthol and 500 m tons of methyl isobutyl ketone were charged into a flask equipped with a thermometer, a condenser, a dropping funnel, and a stirrer, and stirred at room temperature while blowing nitrogen. p-Toluenesulfonic acid 2.
8 g was slowly added dropwise while paying attention to heat generation so that the liquid temperature did not exceed 50°C.

[0040] Thereafter, it was heated to 110°C in an oil bath and heated to 8°C.
Allowed time to react. After the reaction was completed, 500 ml of methyl isobutyl ketone was further added, and the mixture was transferred to a separating funnel and washed with water. After washing with water until the washing water became neutral, the solvent and unreacted substances were removed from the organic layer under reduced pressure to obtain 260 g of resin (A-1) represented by formula (1) of the present invention. The softening temperature (JIS K2425 ring and ball method) of the product (A-1) is 99.
The hydroxyl equivalent (g/eq) was 215 at 5°C. or,
According to GPC analysis, the average value of n in formula (1) was 4.

Example 2 In Example 1, the amount of 1-naphthol used was changed to 173 g (
230 g of product (A-2) was obtained in the same manner as in Example 1, except that 1.2 mol) was used. Product (A-2)
The softening temperature was 110.5°C, and the hydroxyl equivalent (g/eq) was 235. Furthermore, GPC analysis revealed that the average value of n in formula (1) was 5.

Example 3 215 g of the product (A-1) obtained in Example 1 (hydroxyl equivalent (g/eq) 215) and After charging 460 g of epichlorohydrin and purging with nitrogen, 85 g of a 48% aqueous sodium hydroxide solution was added dropwise over 5 hours. During the dropwise addition, the produced water and the water in the aqueous sodium hydroxide solution were continuously removed from the reaction system by azeotropy with epichlorohydrin under conditions of a reaction temperature of 60° C. and a pressure of 100 to 150 mmHg, and epichlorohydrin was returned to the system.

Then, after recovering excess unreacted epichlorohydrin under reduced pressure, 500 m of methyl isobutyl ketone was added.
1 was added and washed with 100 ml of water until the aqueous layer became neutral. Methyl isobutyl ketone was removed from the organic layer under reduced pressure, and then 400 g of methyl isobutyl ketone was added again to dissolve it again. Add 2 to the obtained methyl isobutyl ketone solution.
Add 20g of 0% sodium hydroxide aqueous solution and reaction temperature: 70℃
It reacted for 2 hours.

After the reaction was completed, the aqueous layer was washed with water until it became neutral, and methyl isobutyl ketone was removed from the oil layer under reduced pressure to obtain 268 g of a pale yellow solid (B-1). Product (B-1) which is an epoxy resin represented by formula (2) of the present invention
) had a softening temperature (JIS K2425) of 86°C and an epoxy equivalent (g/eq) of 295. Furthermore, GPC analysis revealed that the average value of n in formula (2) was 4.

Example 4 The product (A-1) obtained in Example 2 was replaced with the product (A-1).
-2) (hydroxyl group equivalent (g/eq) 235) The reaction was carried out in the same manner as in Example 3 except that 235 g of the product (B
-2) was obtained. Product (B-2), which is an epoxy resin represented by formula (2) of the present invention, had a softening temperature of 95°C and an epoxy equivalent (g/eq) of 309. Furthermore, GPC analysis revealed that the average value of n in formula (2) was 5.

Example 5 The product (A-1) obtained in Example 1 (hydroxyl equivalent (g/eq)
215), 460 g of epichlorohydrin, and 239 g of dimethyl sulfoxide were charged and purged with nitrogen, and then 40 g of sodium hydroxide was gradually added in a water bath at 30°C. 5 hours at 30°C, paying attention to heat generation.
The reaction was carried out at 70°C for 2 hours and then at 70°C for 1 hour. Then, water was added to wash the mixture until the aqueous layer became neutral. Thereafter, epichlorohydrin and dimethyl sulfoxide were removed from the oil layer under reduced pressure. Next, 400 g of methyl isobutyl ketone was added and redissolved.

2 to the obtained methyl isobutyl ketone solution.
Add 20g of 0% sodium hydroxide aqueous solution and raise the reaction temperature to 7.
The reaction was carried out at 0°C for 2 hours. After the reaction was completed, the aqueous layer was washed with water until it became neutral, and methyl isobutyl ketone was removed from the oil layer under reduced pressure to obtain 263 g of a pale yellow solid (B-3). The softening temperature of the product (B-3), which is an epoxy resin represented by formula (2) of the present invention, is 85°C and the epoxy equivalent (g/
eq) was 294. Furthermore, from GPC analysis, the formula (2
) was 4.

Example 6 The product (A-1) obtained in Example 2 was replaced with the product (A-1).
-2) (hydroxyl group equivalent (g/eq) 235) The reaction was carried out in the same manner as in Example 5 except that 235 g of the product (B
-4) was obtained. Product (B-4), which is an epoxy resin represented by formula (2) of the present invention, had a softening temperature of 94°C and an epoxy equivalent (g/eq) of 307. Further, from GPC analysis, the value of n in formula (2) was 5.

Application Examples 1-2. Products obtained in Examples 1-2 as curing agents (A-1)
~ (A-2), using a cresol novolac type epoxy resin as the epoxy resin, and using 2-methylimidazole as a curing accelerator, and blending these in the proportions shown in Table 1, a composition was prepared at 70 to 80°C for 15 minutes. Roll kneaded. After cooling it, it was crushed, made into tablets, molded using a transfer molding machine, and precured at 160°C for 2 hours.
Post-curing was performed at 180° C. for 8 hours to obtain a cured product (test piece). The glass transition temperature (Tg), heat distortion temperature (HDT), and water absorption rate of this cured product were measured under the following conditions.

Glass transition temperature thermomechanical measuring device (TMA): Shinku Riko Co., Ltd. TM-70
00 Heating rate: 2℃/min Heat distortion temperature Conditions specified in JIS K7207

Water absorption test piece Diameter 50mm (cured product) Thickness 3mm disk strip
Weight increase after boiling in water at 100℃ for 20 hours (weight%)

Adhesion Adhesive strength was evaluated by tensile shear according to ASTM D1002. The following criteria were used as a guideline for adhesion.

Application Examples 3-4. Products obtained in Examples 1-2 as curing agents (A-1)
- (A-2), using the products (B-1) - (B-2) obtained in Examples 3-4 as epoxy resins, using 2-methylimidazole as a curing accelerator, and using these as the first They were blended in the proportions shown in the table and tested in the same manner as in Application Examples 1 and 2. The evaluation results of the cured products are shown in Table 1.

Application Examples 5-6. Products (B-1)-(
B-2), 2-methylimidazole was used as a curing accelerator, these were blended in the proportions shown in Table 1, and the following tests were conducted in the same manner as in Application Examples 1 and 2. The evaluation results of the cured products are shown in Table 1.

Application comparative examples 1 to 3. Phenol novolac resin (PN(H-1)) was used as a commercially available curing agent in the proportions shown in Table 1, and cresol novolac type epoxy resin (EOCN1020) was used as epoxy resin.
), polyepoxy compound of polyphenol obtained by condensing aromatic aldehyde and phenol (EPPN502
) or bisphenol type epoxy resin (Epomic R
301) and a curing accelerator were blended, and the cured product was evaluated in the same manner as in Application Examples 1 and 2. The evaluation results are shown in Table 1.

The commercially available curing agent and epoxy resin blended are as follows. PN (H-1): (manufactured by Nippon Kayaku Co., Ltd.) Phenol novolak resin hydroxyl equivalent (g/eq) 106 Softening temperature 85°C EO
CN1020: (manufactured by Nippon Kayaku Co., Ltd.) Cresol novolac type epoxy resin Epoxy equivalent (g/eq) 200 Softening temperature 65°C

0
[057] Epomic R-301: (manufactured by Mitsui Petrochemical Epoxy Co., Ltd.) Bisphenol A type epoxy resin Epoxy equivalent (g/eq) 470 Softening temperature 68°C EP
PN502: (manufactured by Nippon Kayaku Co., Ltd.) Polyepoxy compound Epoxy equivalent weight (g/eq) 168 Softening temperature 70°C

0
058]
Table 1 (1)
Application examples
1 2
3 Curing agent product (A-1
) 215
215 Product (A-2)
235
PN (H-1) Epoxy product (B-1)
294 Resin Product (B-2) EOCN-10
20 200 200
Epomic R-301
EPPN-502 Curing accelerator (2-methylimida 2.0 2.0 2.9
sol) Glass transition temperature (℃)
176 180 178 Heat distortion temperature (℃) 18
2 188 189 Water absorption rate (
%) 0.89 0
．． 91 0.82 Adhesiveness
○
○ ◎

[0059]
Table 1 (2)
Application examples
4 5
6 Curing agent product (A-1
) Product (A-2)
235 PN (H-
1) 106
106 Epoxy product (B-1)
294 Resin Product (B-2) 307
307
EOCN-1020 Epomic R-301 EPPN-50
2 Curing accelerator (2-methylimida 3.
1 2.9 3.1
Glass transition temperature (℃) 181
170 172 Heat distortion temperature (℃)
192 176
178 Water absorption rate (%)
0.84 0.86 0.88
Adhesiveness
◎ ○
○

[0060]
Table 1 (3)
Application comparison example
1 2
3 Curing agent product (A-1
) Product (A-2)
PN (H-1) 1
06 106 106 Epoxy product (B-1) Resin product (B-2)
EOCN-1020 200
Epomic R-301
470E
PPN-502
168 Curing accelerator (2-methylimida 2.0 4.7 1
．． 7
sol) Glass transition temperature (℃)
162 125 177
Heat distortion temperature (℃)
178 130 213 Water absorption rate
(%) 1.40
1.20 2.00 Adhesiveness
○
◎ △

[0061]

[Effects of the Invention] The resin of the present invention has a low softening temperature and is excellent in workability. In addition, the cured product obtained using this resin has a high glass transition temperature and heat distortion temperature, which are indicators of heat resistance, and has a lower water absorption rate than conventional resins, and also has good adhesive properties. .

Therefore, the resin of the present invention has high heat resistance and
It can fully meet the requirements for low water absorption and high adhesion, and by utilizing this performance, it is extremely useful in a wide range of fields, specifically as a sealing material for electronic components, a molding material, or a material for lamination.

Claims (7)

[Claims] [Claim 1] Formula (1) (However, in the formula, n is 0 to 15.) A resin represented by the following formula. 2. An epoxy resin represented by formula (2) (wherein n is 0 to 15). 3. An epoxy resin composition comprising (A) an epoxy resin and (B) the resin according to claim 1 as a curing agent. Claim 4: (A) Claim 2 as an epoxy resin
An epoxy resin composition comprising the epoxy resin described above and (B) a curing agent. Claim 5: (A) Claim 2 as an epoxy resin
Claim 1 comprising the epoxy resin described above and (B) a curing agent.
An epoxy resin composition comprising the resin described above. 6. The epoxy resin composition according to claim 3, comprising a curing accelerator. 7. A cured product of the epoxy resin composition according to claim 3, 4, 5, or 6.