JPH05186546A - Polyhydroxynaphthalene compound and epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give a cured resin having a high glass transition temperature and excellent heat resistance and humidity resistance, scarcely suffers package cracking even in soldering treatment, and is suited for sealing semiconductors. CONSTITUTION:alpha-Naphthol, beta-naphthol and an aldehyde compound are subjected to a cocondensation reaction to obtain a polyhydroxynaphthalene compound of a weight-average molecular weight of 300-2000. This compound is useful as a curing agent for an epoxy resin or as a precursor of an epoxy resin. The title composition includes one containing the above compound as a curing agent and an epoxy resin and one comprising an epoxy resin obtained by reacting the above compound with epihalohydrin and a curing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyhydroxynaphthalene compound useful as a curing agent for an epoxy resin or a precursor of an epoxy resin, and a highly reliable epoxy resin composition for encapsulating a semiconductor.

[0002]

2. Description of the Related Art Conventionally, in order to protect a semiconductor element from the external environment, a method of sealing with an epoxy resin composition has been widely adopted. The composition is usually composed of an epoxy resin, a curing agent, a curing accelerator, a filler, and other additives. As the epoxy resin, a resin obtained by epoxidizing a novolac resin obtained by the reaction of phenols and formaldehyde, in particular, orthocresol novolac epoxy resin is widely used, and a phenol formaldehyde novolac resin is adopted as a curing agent. .. Further, a novolak resin obtained by reacting α-naphthol and an aldehyde as a high-performance curing agent and an epoxy resin based on this have been introduced, but the softening point and melt viscosity are high, and workability such as molding is poor. It has not been put to practical use. On the other hand, it is reported that β-naphthol is not used because it hardly forms a resin.

In recent years, semiconductor devices have become more highly integrated and larger in size, flat packages with a large number of pins have been put into practical use, and the proportion of epoxy resin in the encapsulated devices tends to decrease. For this reason, strong stress is likely to be applied during sealing, and the mounting method is also the surface mounting method.Since the resin-sealed semiconductor is immersed in molten solder during mounting, strong thermal stress is applied and moisture is absorbed inside the resin. The exposed water is exposed to a severe environment where it vaporizes rapidly and causes volume expansion.

When a large-capacity semiconductor is encapsulated by using the epoxy resin, there arises a problem that cracks are generated in the package, the bonding wires are deformed or broken due to corrosion, and cracks in element passivation occur. There is an easy problem. Therefore, various high-performance epoxy resins have been proposed, but the problem has not been solved yet.

[0005]

The object of the present invention is that it is useful as a curing agent for epoxy resins or a precursor for epoxy resins, has a high glass transition temperature, heat resistance and moisture resistance, and cracks occur in the package. Another object of the present invention is to provide a polyhydroxynaphthalene-based compound that gives a cured product that can prevent the occurrence of heat.

An object of the present invention is to provide a novel epoxy resin composition and an epoxy resin having a high glass transition temperature, excellent heat resistance and moisture resistance and capable of preventing cracks from being generated in a package.

Another object of the present invention is to provide an epoxy resin composition and an epoxy resin useful as a semiconductor encapsulating material.

[0008]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found that (1) β-naphthol alone does not smoothly react with an aldehyde compound, but α-naphthol When used in combination with β-naphthol, the co-condensation reaction proceeds smoothly with the aldehyde compound, and (2) the resulting co-condensate has a low softening point and melt viscosity, excellent workability, and a high glass transition after curing. The present invention has been completed by discovering that it exhibits temperature and is excellent in heat resistance and moisture resistance, and (3) the cocondensate is useful as a precursor of an epoxy resin as well as a curing agent for an epoxy resin. did.

That is, the present invention provides a polyhydroxynaphthalene compound which is a curing agent for an epoxy resin or a precursor for an epoxy resin, which is obtained by cocondensation of α-naphthol, β-naphthol and an aldehyde compound.

The polyhydroxynaphthalene compound preferably has a weight average molecular weight of 300 to 2000,
It is preferable that 70 to 30 mol% of the α-naphthol unit and 30 to 70 mol% of the β-naphthol unit are co-condensed with the aldehyde, and the weight average molecular weight is 300 to 1500. The hydroxyl equivalent is 100 to 500, preferably 110 to 300.

All molecular weights were measured by gel permeation chromatography (GPC method) using polystyrene of known molecular weight, and the measurement conditions are as shown below.

Solvent: Tetrahydrofuran, Flow:
0.8 ml / min column: G4000H, G30 manufactured by Toyo Soda Industry Co., Ltd.
00H, G2000H (series) and exclusion limit molecular weights of 400,000, 60,000 and 100, respectively.
00.

Carrier: Styrenedivinylbenzene Copolymer The present invention provides an epoxy resin composition containing a curing agent composed of the polyhydroxynaphthalene compound and an epoxy resin.

The present invention also provides an epoxy resin composition containing a polyfunctional epoxy resin obtained from the polyhydroxynaphthalene compound and epihalohydrin, as well as the epoxy resin and a curing agent.

The epoxy resin composition of the present invention containing a polyhydroxynaphthalene compound as a curing agent, and the epoxy resin composition of the present invention containing an epoxy resin derived from a polyhydroxynaphthalene compound contain a curing accelerator. Is preferred, and in that case, it is particularly useful as a semiconductor encapsulating composition.

In the present specification, the term "epoxy resin" is used to include not only a resinous epoxy compound but also a low molecular weight epoxy compound unless otherwise specified.

[Requirements Constituting Means] The main feature of the present invention lies in that the polyhydroxynaphthalene compound is a co-condensation product of α-naphthol, β-naphthol and an aldehyde compound. That is, even if β-naphthol is reacted with an aldehyde compound, the condensation reaction does not proceed and a resinous compound cannot be obtained. However, when β-naphthol is reacted with an aldehyde compound in the presence of α-naphthol, the cocondensation reaction proceeds smoothly and a polyhydroxynaphthalene compound is produced.

In the polyhydroxynaphthalene compound of the first invention, the ratio of α-naphthol and β-naphthol can be appropriately selected within the range where a cocondensate is formed, but preferably α-naphthol: β- Naphthol = 85
-15: 15-85 (mol%), preferably 70-3
It is 0:30 to 70 (mol%). When the amount of α-naphthol is more than the above range, the softening point and melt viscosity of the polyhydroxynaphthalene compound are high, the workability is poor and the heat resistance of the cured product is slightly poor, and the amount of β-naphthol is too large α
-It becomes difficult for the co-condensation reaction with naphthol to proceed, and the heat resistance tends to decrease.

Examples of the aldehyde compound include aliphatic aldehydes such as formaldehyde, acetaldehyde, propylaldehyde and butyraldehyde; aromatic aldehydes such as benzaldehyde, p-hydroxybenzaldehyde and salicylaldehyde; polyhydric aldehydes such as glyoxal and terephthalaldehyde. Is exemplified. Of these compounds, formaldehyde, benzaldehyde, p-hydroxybenzaldehyde, salicylaldehyde, glyoxal and terephthalaldehyde are preferable. These aldehyde compounds may be used alone or in combination of two or more. The weight average molecular weight of the aldehyde compound is preferably 300 or less.

The amount of the aldehyde compound charged varies depending on the number of formyl groups in one molecule of the aldehyde compound, etc., but is usually 0.3 to 0. 0 per 1 mol of α-naphthol and β-naphthol. 9 mol, preferably 0.
It is 4 to 0.8 mol. When the charged amount of the aldehyde compound is small, the heat resistance of the cured product of the epoxy resin composition decreases because the molecular weight of the cocondensate becomes small, and when it is too large, the weight average molecular weight becomes too high and the softening point and melt viscosity are Since it becomes high, there is a problem in moldability. In addition, in the reaction, an excess amount of the aldehyde compound may be used and a part of them may be removed in the reaction process.

The weight average molecular weight of the cocondensate is 300 to 2
000, preferably 300 to 1500.

The cocondensation reaction can be carried out by a conventional method, for example, using an acid catalyst or a basic catalyst. In the reaction, a two-step method in which a basic catalyst is first added to the reaction system and then an acid catalyst is added can be adopted. The co-condensation reaction is generally performed in the presence of an acid catalyst.

As the acid catalyst, mineral acids such as sulfuric acid, hydrochloric acid, nitric acid and hydrobromic acid; sulfonic acids such as p-toluenesulfonic acid and benzenesulfonic acid, oxalic acid, succinic acid,
Examples are organic acids such as malonic acid. It is also possible to heat and react at a high temperature without using a catalyst.

The reaction can be carried out in the absence of a solvent, but may be carried out in the presence of a solvent. As the solvent, various organic solvents inert to the reaction, for example, aromatic hydrocarbons such as benzene and toluene; chlorobenzene,
Halogenated hydrocarbons such as dichlorobenzene; Ketones such as methyl ethyl ketone and methyl isobutyl ketone;
Ethers such as tetrahydrofuran; aprotic polar solvents such as dimethyl sulfoxide and dimethyl sulfamide; mixed solvents thereof and the like.

The reaction temperature can be appropriately selected depending on the type of reaction components, and for example, the reaction temperature is about 50 to 200 ° C. When a preferred aliphatic aldehyde is used, the reaction temperature is 60 to 150 ° C, and when an aromatic aldehyde is used, the reaction temperature is 60 to 190 ° C. The reaction is usually completed in about 1 to 10 hours.

After the completion of the reaction, if necessary, impurities may be removed by washing with water, or unreacted monomers may be removed by a method such as solvent washing or degassing under reduced pressure.

The polyhydroxynaphthalene compound obtained by such a reaction is useful as a curing agent for an epoxy resin and a precursor for an epoxy resin.

A second invention comprises the above-mentioned polyhydroxynaphthalene compound which functions as a curing agent, and an epoxy resin. The composition preferably further contains a curing accelerator, and in this case, it is particularly useful as a semiconductor encapsulating resin composition.

When used as a curing agent for an epoxy resin, the polyhydroxynaphthalene compound may be used alone, and another curing agent comprising a compound having two or more, preferably three or more phenolic hydroxyl groups in the molecule. It can also be used in combination with an agent. As other curing agents, for example, phenol or a substituted phenol (o-cresol, p-cresol, t-butylphenol, cumylphenol, phenylphenol, etc.) and an aldehyde compound are reacted in the presence of an acid catalyst or a basic catalyst. Examples thereof include a usual phenol resin that has been allowed to react; a reaction product of resorcin and an aldehyde compound; polyvinylphenol and the like. The ratio of the other curing agent is 70 wt% or less, preferably 50 wt% or less in the curing agent.

The type of epoxy resin is not particularly limited, and conventionally known ones can be used. For example, bisphenol A
Type, phenol novolac type, cresol novolac type epoxy resin and the like. Among these resins, those having a softening point above room temperature and exhibiting a solid state or a highly viscous solution state at room temperature give good results.

The bisphenol A type epoxy resin is usually an epoxy equivalent of 160 to 200 and a softening point of 50.
The epoxy novolac type epoxy resin having an epoxy equivalent of 180 to 210,
A cresol novolac type epoxy resin having a softening point of 50 to 130 ° C. is used and has an epoxy equivalent of 180.
˜210 and softening point of 60 to 110 ° C. are generally used.

The ratio of the epoxy resin to the curing agent is such that the equivalent ratio of the phenolic hydroxyl group of the curing agent to the epoxy group of the epoxy resin (epoxy group / phenolic hydroxyl group) is usually 1 / 0.8 to 1.2, preferably The range of 1 / 0.9 to 1.1 is preferable. When the epoxy resin and the curing agent are used in such a ratio, a cured product having excellent heat resistance and moisture resistance can be obtained.

As the curing accelerator, an ordinary catalyst can be used, and the kind thereof is not particularly limited. Specific examples of the curing accelerator include, for example, triphenylphosphine, tris-2,6-dimethoxyphenylphosphine, tri-p.
-Phosphorus compounds such as tolylphosphine and triphenyl phosphite; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole; Tertiary amines such as 2-dimethylaminomethylphenol, benzyldimethylamine, α-methylbenzylmethylamine; 1,5-diazabicyclo [4.3.0] -5-nonene, 1,4-diazabicyclo [2.2] .2] octane, organic bases of 1,8-diazabicyclo [5.4.0] -7-undecene, and the like.

From the viewpoint of heat resistance and humidity resistance, the amount of the curing accelerator added is preferably 0.1 to 3.0% by weight in the epoxy resin composition.

The polyhydroxynaphthalene compound is also useful as a precursor of an epoxy resin.

The epoxy resin of the third invention can be obtained by reacting the polyhydroxynaphthalene compound with epihalohydrin.

Examples of epihalohydrin include epichlorohydrin, epibromohydrin, β-methylepichlorohydrin, β-methylepibromohydrin, β-methylepiiodohydrin and the like. Preferred epihalohydrins include epichlorohydrin.

The reaction between the polyhydroxynaphthalene compound and epihalohydrin can be carried out by a conventional method, for example, the following two typical methods.

1) A one-step method in which a polyhydroxynaphthalene compound and an excess of epihalohydrin are reacted in the presence of an alkali metal hydroxide to simultaneously carry out an addition reaction and a ring-closing reaction to form an epoxy ring.

2) A two-step method in which a polyhydroxynaphthalene compound and an excess of epihalohydrin are subjected to an addition reaction in the presence of a basic catalyst, and then an alkali metal hydroxide is added to carry out a ring-closing reaction.

In the one-step method and the two-step method, the amount of epihalohydrin used is usually 1.3 to 2 with respect to 1 equivalent of the hydroxyl group of the polyhydroxynaphthalene compound.
It is 0 molar equivalent, preferably 2 to 10 molar equivalents. Excess epihalohydrin can be recovered and reused after the reaction.

Sodium hydroxide or potassium hydroxide can be used as the alkali metal hydroxide in the one-step method and the two-step method. These alkali metal hydroxides may be added to the reaction system as a solid, or may be added to the reaction system as an aqueous solution of about 40 to 50% by weight. The amount of alkali hydroxide used is 0.8 to 1.5 molar equivalents, preferably 0.9 to 1.1 molar equivalents, per equivalent of hydroxyl groups of the polyhydroxynaphthalene compound.

The reaction in the one-step method is, for example, 50 to 1
It can be carried out at a temperature of 50 ° C, preferably 80 to 120 ° C.

As the basic catalyst in the two-step method,
For example, tetramethylammonium chloride, tetramethylammonium bromide, tetraethylammonium chloride, tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium bromide, triethylmethylammonium chloride,
Examples thereof include quaternary ammonium salts such as trimethylbenzylammonium chloride and triethylbenzylammonium chloride.

The basic catalyst is 0.002 to 3.0 with respect to the hydroxyl group of the polyhydroxynaphthalene compound.
It can be used in the proportion of mol%.

In the above two-step method, the reaction in the first step can be carried out at a temperature of, for example, 60 to 150 ° C, preferably 100 to 140 ° C.

The reaction in the latter stage can be carried out at 20 to 150 ° C., preferably 60 to 120 ° C. The amount of the alkali metal hydroxide used in the reaction in the latter stage is about 1 to 1.1 molar amount with respect to the produced halohydrin.

These reactions may be carried out without solvent or in the presence of a solvent inert to the reaction. Examples of the solvent include ketones such as methyl ethyl ketone and methyl isobutyl ketone; alicyclic hydrocarbons such as cyclohexane; aromatic hydrocarbons such as toluene.

After completion of the reaction, the polyfunctional epoxy resin of the present invention can be obtained by removing the catalyst and the like by washing with water, washing with a solvent, degassing under reduced pressure and the like.

The polyfunctional epoxy resin of the present invention is viscous or solid at room temperature and has a weight average molecular weight of 3
It is about 00 to 5000, preferably about 400 to 2000. The epoxy equivalent of the polyfunctional epoxy resin is 1
It is about 30 to 1000, preferably about 150 to 500.

The cured product of the polyfunctional epoxy resin of the present invention has a high glass transition temperature, excellent heat resistance and moisture resistance, high strength at the solder reflow temperature, low hygroscopicity, and cracks in the package. Prevent it from happening. Therefore, the polyfunctional epoxy resin derived from the polyhydroxynaphthalene compound is useful as a material for the epoxy resin composition for semiconductor encapsulation.

The epoxy resin composition of the fourth invention comprises a polyfunctional epoxy resin derived from the polyhydroxynaphthalene compound and a curing agent. The composition preferably further contains a curing accelerator, and in this case, it is particularly useful as a semiconductor encapsulating resin composition.

The polyfunctional epoxy resin may be used alone or in combination with other epoxy resins such as phenol novolac type, cresol novolac type epoxy resin and bisphenol A type epoxy resin. The ratio of other epoxy resin is 70 wt% or less in the epoxy resin,
It is preferably 50 wt% or less.

As the curing agent, two or more in the molecule,
Preferably, a compound having 3 or more phenolic hydroxyl groups can be used. Specific examples thereof include the polyhydroxynaphthalene-based compound and other curing agents such as a phenol resin which can be used in combination with the epoxy resin composition of the second invention. The proportion of the curing agent is the same as the proportion of the epoxy resin and the curing agent in the second invention.

As the curing accelerator used in the present invention, phosphorus compounds, imidazoles, tertiary amines, organic bases and the like can be used as described above. The amount of the curing accelerator used is the same as the amount used in the second invention.

The epoxy resin composition of the present invention may contain additives as required. Examples of the additive include a filler, a surface treatment agent for treating the surface of the filler, a flame retardant, a release agent, a colorant, and a flexibility-imparting agent.

The kind of the filler is not particularly limited, and examples thereof include crystalline silica powder, fusible silica powder, quartz glass powder,
Talc, calcium silicate powder, zirconium silicate powder,
Examples thereof include alumina powder and calcium carbonate powder. Among these fillers, silica-based fillers are preferable. The proportion of filler is 60-90 wt%, preferably 70-85 wt%, based on the total composition. 90w of filler
If it exceeds t%, the fluidity of the composition tends to be low, making molding difficult, and if it is less than 60 wt%, the thermal expansion tends to be large.

Examples of the surface treatment agent include known silane coupling agents and the like, and examples of the flame retardant include antimony trioxide, antimony pentoxide, phosphates and bromides. Examples of the release agent include various waxes,
Carbon black etc. are mentioned as a coloring agent.
The flexibility-imparting agent includes, for example, silicone resin and butadiene-acrylonitrile rubber.

The method for preparing the epoxy resin composition of the present invention is not particularly limited, and the epoxy resin composition can be prepared by a conventional method. In addition, conditions for encapsulating a semiconductor using the resin composition of the present invention can be appropriately selected and are not particularly limited. A specific example of the sealing conditions is, for example, 175 ° C., molding pressure 100 kg / cm ² , molding for 3 minutes, and 180 ° C. for 5 hours post-curing. Usually, it is molded by transfer molding.

[0060]

EXAMPLES Hereinafter, the embodiments of the present invention will be specifically described by way of examples. The invention is not limited to these examples.

Example 1 (Polyhydroxynaphthalene Compound 1) 96 g of α-naphthol and 4 of β-naphthol were placed in a reaction vessel equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen inlet.
8g, paraformaldehyde 23g, oxalic acid 0.2g
Was charged, heated to 110 ° C., and stirred for 8 hours under a nitrogen stream to react. After this, heat to 200 ° C., 5 mmH
The unreacted material and water were removed with g. The weight average molecular weight of the obtained cocondensate was 690 and the hydroxyl group equivalent was 158. The softening point is 99 ° C and the melt viscosity at 150 ° C is 4.
The workability was excellent with a low value of 7 poise (hereinafter referred to as P). In addition, also in the following Examples, all the viscosity measurements were performed at 150 ° C.

Example 2 (Polyhydroxynaphthalene compound 2) Using 72 g of α-naphthol and 72 g of β-naphthol,
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1 except that the amount of paraformaldehyde was 21 g. The weight average molecular weight of the obtained cocondensate was 500 and the hydroxyl group equivalent was 157. The softening point was 85 ° C and the viscosity was 2.8P.

Example 3 (Polyhydroxynaphthalene compound 3) Using 48 g of α-naphthol and 96 g of β-naphthol,
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1 except that the amount of paraformaldehyde was 27 g. The weight average molecular weight of the obtained cocondensate was 910 and the hydroxyl group equivalent was 161. The softening point was 108 ° C and the viscosity was 7.6P.

Example 4 (Polyhydroxynaphthalene Compound 4) Benzaldehyde 70 was used instead of paraformaldehyde.
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1 except that p-toluenesulfonic acid was used instead of g and oxalic acid. The weight average molecular weight of the obtained cocondensate was 630 and the hydroxyl equivalent was 204. The softening point was 91 ° C and the viscosity was 3.2P.

Example 5 (Polyhydroxynaphthalene-based compound 5) Except that 78 g of p-hydroxybenzaldehyde was used in place of paraformaldehyde and the reaction temperature was 180 ° C.
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1. The weight average molecular weight of the obtained cocondensate was 680 and the hydroxyl group equivalent was 125. Softening point is 109
C. and viscosity were 6.8P.

Example 6 (Polyhydroxynaphthalene Compound 6) Salicylaldehyde 78 instead of paraformaldehyde
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1 except that the reaction temperature was 180 ° C. The weight average molecular weight of the obtained cocondensate was 670 and the hydroxyl group equivalent was 127. The softening point was 108 ° C and the viscosity was 7.6P.

Example 7 (Polyhydroxynaphthalene compound 7) Terephthalaldehyde 5 was used instead of paraformaldehyde.
A polyhydroxynaphthalene-based compound was produced in the same manner as in Example 1 except that 7 g was used. The weight average molecular weight of the obtained cocondensate was 880 and the hydroxyl equivalent was 175. The softening point was 104 ° C and the viscosity was 6.8P.

Examples 8 to 14 and Comparative Example 1 The following epoxy resin, curing agent, curing accelerator, filler, antimony trioxide, silane coupling agent, wax and carbon black were added in the proportions shown in Table 1. The mixture was blended, kneaded with a two-roll mill at a temperature of 70 to 110 ° C., cooled, and pulverized to prepare an epoxy resin composition for semiconductor encapsulation.

Epoxy resin: o-cresol novolac type epoxy resin Epoxy equivalent 195 Softening point 85 ° C. Brominated phenol novolac type epoxy resin Epoxy equivalent 280 Softening point 83 ° C. Curing agent: each polyhydroxynaphthalene obtained in Examples 1 to 7 System compound Phenol novolac resin Hydroxyl equivalent 106 Softening point 80 ° C Curing accelerator: Triphenylphosphine Filler: Spherical silica (BF100 of Mitsubishi Metals Co., Ltd.) 175 ° C, 100 kg / cm ² , 3
Molding was performed under a curing condition of 1 minute, and then post-curing was performed at 180 ° C. for 6 hours to prepare a molded test piece. This package is an 80-pin four-way flat package (80-pin QFP, size: 20 × 14 × 2 mm) and has a die pad size of 8 × 8 mm.

The semiconductor device thus obtained was subjected to a TCT test of -50 ° C./5 minutes to 150 ° C./5 minutes to check the number of cracks. In addition, the test piece
A test was conducted in which the sample was left in a constant temperature bath having a relative humidity of 5 ° C./85% RH to absorb moisture and then immersed in a solder melt at 260 ° C. for 10 seconds. The results are shown in Table 2 below.

The bending strength (high temperature strength) at 200 ° C. of the obtained test piece, the glass transition temperature, the coefficient of thermal expansion,
The water absorption was examined after a humidification test at 85 ° C. and 85% RH for 500 hours. The results are shown in Table 3 below.

[0072]

[Table 1]

[Table 2]

[Table 3] Example 15 (epoxy resin 1) The total amount of the polyhydroxynaphthalene-based compound obtained in the same manner as in Example 1, 1500 g of epichlorohydrin and 2 g of tetrabutylammonium bromide were charged, and the mixture was reacted under heating under reflux for 3 hours, and then excess under reduced pressure. Epichlorohydrin was removed. Add the same amount of toluene as the contents, 60
40 g of caustic soda after cooling to ℃ and attaching a water removal device
Was added, and the ring closure reaction was carried out while continuously removing the produced water at a reduced pressure of 100 to 150 mmHg. After washing with water to remove salts and unreacted alkali, toluene and water were removed under reduced pressure to obtain an epoxy resin. Weight average molecular weight is 1
230, the epoxy equivalent was 218. Softening point is 85
It had a low working temperature and low viscosity of 3.2P.

Example 16 (Epoxy resin 2) An epoxy resin was obtained in the same manner as in Example 15, except that the total amount of the polyhydroxynaphthalene compound obtained in the same manner as in Example 2 was used. The weight average molecular weight was 880 and the epoxy equivalent was 216. The softening point was 82 ° C and the viscosity was 1.8P.

Example 17 (Epoxy resin 3) An epoxy resin was obtained in the same manner as in Example 15, except that the total amount of the polyhydroxynaphthalene compound obtained in the same manner as in Example 3 was used. The weight average molecular weight is 1430,
The epoxy equivalent was 220. The softening point was 98 ° C and the viscosity was 3.9P.

Example 18 (Epoxy resin 4) Except that in Example 16, 90 g of benzaldehyde was used instead of paraformaldehyde and p-toluenesulfonic acid was used instead of oxalic acid to obtain a polyhydroxynaphthalene compound. An epoxy resin was obtained in the same manner as in Example 15. The weight average molecular weight is 1020,
The epoxy equivalent was 283. The softening point was 87 ° C and the viscosity was 1.9P.

Example 19 (Epoxy resin 5) In Example 16, 98 g of p-hydroxybenzaldehyde was used instead of paraformaldehyde and p-toluenesulfonic acid was used instead of oxalic acid to obtain a polyhydroxynaphthalene compound. , Reaction temperature 180
An epoxy resin was obtained in the same manner as in Example 15 except that the temperature was changed to ° C. The weight average molecular weight was 1120 and the epoxy equivalent was 187. The softening point was 99 ° C and the viscosity was 4.0P.

Example 20 (epoxy resin 6) In Example 16, 98 g of salicylaldehyde was used instead of paraformaldehyde and p-toluenesulfonic acid was used instead of oxalic acid to obtain a polyhydroxynaphthalene compound. An epoxy resin was obtained in the same manner as in Example 15 except that the temperature was set to 180 ° C. The weight average molecular weight was 1110 and the epoxy equivalent was 188. The softening point was 92 ° C and the viscosity was 3.5P.

Example 21 (Epoxy resin 7) In Example 16, except that 57 g of terephthalaldehyde was used instead of paraformaldehyde and p-toluenesulfonic acid was used instead of oxalic acid to obtain a polyhydroxynaphthalene compound. In the same manner as in Example 15, an epoxy resin was obtained. Weight average molecular weight is 133
0, the epoxy equivalent was 251. Softening point is 98 ℃,
The viscosity was 3.6P.

Examples 22 to 28 and Comparative Example 2 The epoxy resin, curing agent, curing accelerator, filler, antimony trioxide, silane coupling agent, wax and carbon black shown below were used in the proportions shown in Table 4. The mixture was blended, kneaded with a two-roll mill at a temperature of 70 to 110 ° C., cooled, and pulverized to prepare an epoxy resin composition for semiconductor encapsulation.

Epoxy resin: Epoxy resins 1 to 7 obtained in Examples 15 to 21 o-cresol novolac epoxy resin epoxy equivalent 195 softening point 85 ° C brominated phenol novolac epoxy resin epoxy equivalent 280 softening point 83 ° C curing agent: phenol Novolac resin Hydroxyl equivalent 106 Softening point 80 ° C. Curing accelerator: Triphenylphosphine Filler: Spherical silica (Mitsubishi Metals Co., Ltd., BF100) The composition obtained was 175 ° C., 100 kg / cm ² , 3
Molding was performed under a curing condition of 1 minute and then post-cured at 180 ° C. for 6 hours to prepare a molded test piece.

The semiconductor device thus obtained was subjected to a TCT test of -50 ° C./5 minutes to 150 ° C./5 minutes to check the number of cracks. In addition, the test piece
A test was conducted in which the sample was left in a constant temperature bath having a relative humidity of 5 ° C./85% RH to absorb moisture and then immersed in a solder melt at 260 ° C. for 10 seconds. The results are shown in Table 5 below.

The bending strength (high temperature strength) at 200 ° C. of the obtained test piece, the glass transition temperature, the coefficient of thermal expansion,
The water absorption was examined after a humidification test at 85 ° C. and 85% RH for 500 hours. The results are shown in Table 6.

[0083]

[Table 4]

[Table 5]

[Table 6]

[0084]

INDUSTRIAL APPLICABILITY The polyhydroxynaphthalene compound of the present invention has a high glass transition temperature, heat resistance and humidity resistance when used as a curing agent for an epoxy resin or a precursor for an epoxy resin, and even in soldering. A cured product that can prevent the package from cracking is provided.

The epoxy resin of the present invention derived from a polyhydroxynaphthalene compound has a high glass transition temperature of a cured product, excellent heat resistance and moisture resistance, and prevents cracks from being generated in the package.

The epoxy resin composition of the present invention containing a polyhydroxynaphthalene compound as a curing agent and the epoxy resin composition of the present invention containing an epoxy resin derived from a polyhydroxynaphthalene compound have a glass transition temperature of a cured resin. It has high heat resistance, high mechanical strength, high water resistance, low moisture absorption, and very few cracks during soldering. Therefore, it is useful as a composition for semiconductor encapsulation. Further, the epoxy resin composition preferably contains a curing accelerator, and in that case, it is particularly useful for encapsulating a semiconductor.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C08G 59/20 NHQ 8416-4J 59/40 NJU 8416-4J H01L 23/29 23/31 (72) Inventor Shinya Akizuki 1-2-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation (72) Inventor Kiyoshi Saito 1-21-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation

Claims (8)

[Claims] 1. A polyhydroxynaphthalene-based compound which is a curing agent for an epoxy resin or a precursor for an epoxy resin, which is obtained by cocondensation of α-naphthol, β-naphthol and an aldehyde compound. 2. The polyhydroxynaphthalene compound according to claim 1, wherein the polyhydroxynaphthalene compound has a weight average molecular weight of 300 to 2,000. 3. An α-naphthol unit 70 to 30 mol% and a β-naphthol unit 30 to 70 mol% are co-condensed with an aldehyde and have a weight average molecular weight of 300 to 150.
The polyhydroxynaphthalene compound according to claim 1, which is 0. 4. An epoxy resin composition containing a curing agent comprising the polyhydroxynaphthalene compound according to claim 1 and an epoxy resin. 5. An epoxy resin composition for semiconductor encapsulation, comprising a curing agent comprising the polyhydroxynaphthalene compound according to claim 1, an epoxy resin, and a curing accelerator. 6. A polyfunctional epoxy resin obtained by reacting the polyhydroxynaphthalene compound according to claim 1 with epihalohydrin. 7. An epoxy resin composition containing the epoxy resin according to claim 6 and a curing agent. 8. An epoxy resin composition for semiconductor encapsulation, comprising the epoxy resin according to claim 6, a curing agent, and a curing accelerator.