JP2876304B2 - Epoxy resin curing agent and curable epoxy resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin curing agent which gives a cured product having excellent heat resistance and low hygroscopicity, and a curable epoxy resin composition using the epoxy resin curing agent.

[0002]

2. Description of the Related Art In recent years, the required characteristics of a polymer material have become strict, and its use conditions have become severe. In particular, a curable epoxy resin composition using a phenol resin as a curing agent is used for semiconductor encapsulation, but the required performance is strict in this field as well.

[0003] That is, as the integration of semiconductor devices has progressed, the size of semiconductor elements has increased remarkably, and the packages themselves have become smaller and thinner. In addition, the mounting of semiconductor elements has also shifted to the surface mounting method. In surface mounting, since the semiconductor device is directly immersed in a solder bath and exposed to high temperatures, the moisture absorbed in the sealing material expands. , Cracks in the sealing material. For this reason, a sealing material having good solder crack resistance is required to have high heat resistance and low moisture absorption, and an epoxy using a cresol novolak type epoxy resin, which is currently mainly used, and a phenol novolak resin curing agent. The resin sealing material is not sufficient in heat resistance and hygroscopicity.

For these reasons, it has been attempted to use a condensate of phenol and hydroxybenzaldehyde as an epoxy resin curing agent, or use an epoxidized product of the same as an epoxy resin. Although the heat resistance can be improved, the hygroscopicity is increased, which is not useful for improving the solder crack resistance.

There is also a proposal to improve the hygroscopicity by introducing an alkyl substituent into the epoxy resin or its curing agent. However, in this case, the heat resistance is reduced, so that the heat resistance and the low hygroscopicity are reduced. Can not be compatible.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an epoxy resin curing agent and a curable epoxy resin composition which provide a cured product having excellent heat resistance and low hygroscopicity.

[0007]

The present inventors have conducted various studies to solve the above-mentioned problems, and as a result, have found that a specific polyhydric phenol compound having a cyclic terpene skeleton is used as an epoxy resin curing agent. As a result, the purpose was achieved.

That is, the epoxy resin curing agent of the present invention comprises two molecules of phenol per one molecule of a cyclic terpene compound.
It is a curing agent containing a cyclic terpene skeleton-containing polyhydric phenolic compound containing 80% by weight or more of a compound to be added .

Further, the curable epoxy resin composition of the present invention is a composition containing an epoxy resin and the above-mentioned epoxy resin curing agent.

[0010] Two molecules of phenols are added to one molecule of the cyclic terpene compound constituting the main component of the epoxy resin curing agent of the present invention .
The cyclic terpene skeleton-containing polyhydric phenolic compound containing the added compound can be produced by reacting the cyclic terpene compound with a phenol in the presence of an acidic catalyst.

In the present invention, the cyclic terpene compound as a raw material for producing the cyclic terpene skeleton-containing polyhydric phenol compound may be a monocyclic terpene compound,
Bicyclic terpene compounds may be used, and specific examples thereof include the following.

[0012]

Embedded image Limonene:

Dipentene: an optical isomer of limonene.

[0014]

Embedded image Terpinolene:

[0015]

Embedded image Pinene:

[0016]

Embedded image Terpinene:

[0017]

Embedded image Mentadien:

The phenols which are the other raw materials for producing the cyclic terpene skeleton-containing polyhydric phenol compound in the present invention include, for example, phenol, cresol, xylenol, propylphenol, nonylphenol, hydroquinone, resorcinol, methoxyphenol. , Bromophenol, bisphenol A, bisphenol F and the like.

The addition reaction of the cyclic terpene compound with the phenol is carried out by using preferably 2 to 8 mol of the phenol per 1 mol of the cyclic terpene compound, and reacting at a temperature of 40 to 160 ° C. in the presence of an acid catalyst. Let run for ~ 10 hours.
Examples of the acidic catalyst include hydrochloric acid, sulfuric acid, phosphoric acid, polyphosphoric acid, boron trifluoride or a complex thereof, and activated clay. The reaction solvent may not be used, but usually, a solvent such as an aromatic hydrocarbon, an alcohol, or an ether is used.

The polyhydric phenolic compound having a cyclic terpene skeleton according to the present invention thus produced is mainly composed of
Phenols in one molecule of cyclic terpene compound as a component
Contains a compound obtained by adding two molecules. For example, any of those produced from limonene and phenol or those produced from α-terpinene and phenol are represented by a compound represented by the following structural formula (I) and a compound represented by the following structural formula (II) Cyclic terpes of the compound
By adding two molecules of phenols to one molecule of compound
Contains compounds.

[0021]

Embedded image

Conversion of polyhydric phenol containing cyclic terpene skeleton
Phenols per molecule of cyclic terpene compound in compound
The content of the compound obtained by molecular addition is 80% by weight or more.
Needs to be Pheno in one molecule of cyclic terpene compound
The content of the compound obtained by adding two molecules of
And the effect of the present invention cannot be sufficiently exhibited. In addition,
The content should be measured by liquid chromatography.
Can be. As described above, the epoxy resin curing agent of the present invention is a curing agent containing the cyclic terpene skeleton-containing polyhydric phenol-based compound thus produced as a main component. That is, the epoxy resin curing agent of the present invention may be composed only of the cyclic terpene skeleton-containing polyhydric phenolic compound, or may be a combination of a small amount of another epoxy resin curing agent. .

Other epoxy resin curing agents that can be used in combination include phenolic resins such as novolak phenolic resins and novolak cresol resins, acid anhydrides such as tetrahydrophthalic anhydride and pyromellitic anhydride, diaminodiphenylmethane, and the like. Amines such as diaminodiphenylsulfone; The amount of these other curing agents to be used in combination should not exceed 50% by weight, based on the total amount of curing agents. If the amount of the other epoxy resin curing agent is too large, the excellent effects of the curing agent of the present invention cannot be sufficiently exhibited.

Next, the curable epoxy resin composition of the present invention is a composition containing an epoxy resin and the above-described epoxy resin curing agent of the present invention.

The epoxy resin has no particular limitation.
Those used in ordinary epoxy resin compositions can be used. For example, various phenols such as bisphenol A, bisphenol F, resorcin, hydroquinone, biphenol, tetramethylbiphenol, phenol novolak, cresol novolak, bisphenol A novolak, and various other phenols such as hydroxybenzaldehyde, crotonaldehyde, glyoxal, etc. Epoxy resins produced from various phenolic compounds such as polyhydric phenolic resins obtained by a condensation reaction with aldehydes and epihalohydrin,
Examples include epoxy resins produced from various amines such as diaminodiphenylmethane, aminophenol, xylenediamine and epichlorohydrin.

The curable epoxy resin composition of the present invention comprises
If necessary, a curing accelerator, a filler, a coupling agent, a flame retardant, a plasticizer, a solvent, a reactive diluent, a pigment and the like can be appropriately compounded.

Examples of the curing accelerator include imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole, and amines such as 2,4,6-tris (dimethylaminomethyl) phenol and benzyldimethylamine. And organic phosphorus compounds such as tributylphosphine and triphenylphosphine.

Examples of the filler include fused silica, crystalline silica, glass powder, alumina, and zircon. Examples of the flame retardant include antimony trioxide and phosphoric acid. Flame retardation can also be achieved by using a brominated epoxy resin for part of the epoxy resin.

The curable epoxy resin composition of the present invention, that is, the curable epoxy resin composition using the cyclic terpene skeleton-containing polyhydric phenol compound as a main component of a curing agent, is a conventional curable epoxy resin composition. As a result, a cured product having higher heat resistance and lower hygroscopicity is provided, and thus can be advantageously used in fields such as sealing, lamination, and painting.

[0030]

The present invention will be described in more detail with reference to production examples, examples and comparative examples of polyhydric phenol compounds.

Production Example 1 of Polyhydric Phenol Compound 3384 g of phenol and 34 g of boron trifluoride / diethyl ether complex were charged into a three-necked flask having an inner volume of 5 liters equipped with a thermometer, a stirrer, and a cooling tube.
At a temperature of ℃, 816 g of limonene was added dropwise over 3 hours, and the mixture was further stirred and reacted at the same temperature for 2 hours.

Next, the product is washed three times with distilled water and then heated under reduced pressure to remove phenol and by-products.
Finally, the mixture was kept at 160 ° C. and 5 mmHg for 1 hour to obtain 1520 g of a cyclic terpene skeleton-containing polyhydric phenol compound having a softening point of 82 ° C. The result of the liquid chromatography analysis showed that the purity of the polyhydric phenol compound was 89%.

Example 1 Comparative Examples 1 to 4 The polyhydric phenolic compound obtained in Production Example 1 as a curing agent, a phenol novolak resin (in the case of Comparative Examples 1 and 3), or a condensation reaction of phenol with salicylaldehyde The obtained phenolic resin (in the case of Comparative Example 2), commercially available
Terpene phenol resin (in the case of Comparative Example 4), ortho-cresol type epoxy resin as epoxy resin, condensate type epoxy resin of phenol and salicylaldehyde, flame-retardant brominated epoxy resin, antimony trioxide as flame retardant, curing acceleration As shown in Table 1, triphenylphosphine was used as an agent, silica powder was used as a filler, epoxysilane was used as a surface treatment agent, and carnauba wax was used as a release agent.

Next, each of the blends is melt-kneaded at a temperature of 90 to 120 ° C. for 5 minutes using a mixing roll, and each melt mixture obtained is taken out in the form of a sheet, cooled and pulverized to obtain a molding material (cured). Epoxy resin composition).
Each of the molding materials was molded by a low-pressure transfer molding machine at a mold temperature of 180 ° C. and a molding time of 180 seconds, and each test piece for measuring a glass transition temperature, a moisture absorption rate and a bending test, and a simulated element were sealed. A 44-pin FPP (flat plastic package) was obtained and heated at 180 ° C. for 8 hours to post cure. After the post cure, tests such as glass transition temperature, moisture absorption, bending test, and solder heat resistance were performed.

The results are as shown in Table 1. The cured product of the epoxy resin composition of Example 1 has a high glass transition temperature and a low moisture absorption, and therefore has excellent solder crack resistance. It was excellent for semiconductor encapsulation.

[0036]

[Table 1]

Notes to Table 1 * 1: Yuka Shell Epoxy Co., Ltd. Epicoat 180H65, Epoxy equivalent 201 g / eq. , Softening point 67 ° C * 2: Yuka Shell Epoxy Co., Ltd. Epicoat 1032H60, epoxy equivalent 169 g / eq. , Softening point 62 ° C * 3: Yuka Ciel Epoxy Co., Ltd. Epicoat 5050, Epoxy equivalent 385 g / eq. , Bromine content 49% * 4: manufactured by Gunei Chemical Co., Ltd., softening point 85 ° C * 5: softening point 108 ° C, hydroxyl equivalent 98g / eq. * 6: Product name of Tatsumori RD-8 * 7: Product of Shin-Etsu Chemical Co., Ltd. KBM-403 * 8: Calculated from the transition point of the thermal expansion curve using TMA. * 9: Moisture absorption rate after 120 ° C, 100% RH for 200 hours * 10: Sixteen 44-pin FPPs were absorbed at 85 ° C, 85% RH for 168 hours, then immersed in a 260 ° C solder bath for 10 seconds, and cracks appeared. The number of occurrences was determined. * 11: Trade name of Yasuhara Yushi Co., Ltd. Silver Seven, content of compound obtained by adding two molecules of phenol to one molecule of cyclic terpene compound, 50% by weight, softening point 92 ° C

[0038]

The epoxy resin curing agent and the epoxy resin composition of the present invention can provide a cured product having excellent heat resistance and low hygroscopicity.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Fumio Goto, inventor, 1080, Takagicho, Fuchu-shi, Hiroshima, Japan Yashara Chemical Co., Ltd. References JP-A-63-69255 (JP, A) JP-A-55-89318 (JP, A) JP-A-55-94921 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) C08G 59/62 C07C 39/17

Claims (2)

(57) [Claims] 1. A compound obtained by adding two molecules of a phenol to one molecule of a cyclic terpene compound in an amount of 80% by weight or more.
Epoxy resin hardener containing a cyclic terpene skeleton-containing polyhydric phenolic compound as a main component. 2. A curable epoxy resin composition comprising an epoxy resin and the epoxy resin curing agent according to claim 1.