JPH1149846A - Triphenylmethane type phenol resin, epoxy resin composition and cured products of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin low in melt viscosity, excellent in working properties and heat resistance of the cured articles by carrying out a condensation reaction of salicylaldehyde, p-hydroxybenzaldehyde and excess phenol in the presence of an acid catalyst. SOLUTION: The objective resin useful for molding materials, coating compositions, adhesives, etc., of formula I (m, n are average values, m=0.05 to 5, n=0.05 to 3) us obtained by carrying out the condensation reaction of salicylaldehyde, p-hydroxybenzaldehyde(charging weight ratio of 50:50 to 98:2 preferably 60:40 to 95:5) and 2 to 30 mole of phenol per one mole of salicylaldehyde and p-hydroxybenzaldehyde in the presence of 0.001 to 0.1 mole of the acid catalys (e.g. p-toluenesulfonic acid) per one mole of salicylaldehyde and p-hydroxybenzaldehyde.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phenolic resin which provides a cured product having excellent heat resistance and has a low melt viscosity and excellent workability.

[0002]

2. Description of the Related Art Epoxy resins can be cured with various curing agents to give cured products having generally excellent mechanical properties, water resistance, chemical resistance, heat resistance, and electrical properties. It is used in a wide range of fields, such as laminates, molding materials, and casting materials. Conventionally, o-cresol novolak type epoxy resin and phenol novolak have been most commonly used as a curing agent because of their excellent heat resistance, chemical resistance and the like, especially in semiconductor encapsulant applications. However, in recent years, with the change in the package form, the demand for a resin having higher heat resistance has been increasing. As a curing agent that can meet such a requirement, the following formula (2)

[0003]

Embedded image

A triphenylmethane type phenol resin represented by the formula (where n represents an integer) has been proposed.

[0005]

However, the phenolic resin represented by the above formula (2) is excellent in heat resistance, but has a relatively high viscosity, so that the epoxy resin is kneaded when preparing the composition. Difficulty arises in that the bonding wire connecting the silicon chip and the lead frame is bent or broken when sealing the semiconductor (wire sweep).

[0006]

Means for Solving the Problems In view of these circumstances, the present inventors have intensively studied for a resin having high heat resistance, low viscosity and excellent workability. As a result, salicylaldehyde,
It has been found that a cured product of an epoxy resin composition containing a phenolic resin obtained by condensing p-hydroxybenzaldehyde and phenol has low viscosity and good workability while maintaining high heat resistance. It has been completed.

That is, the present invention provides (1) the following formula (1)

[0008]

Embedded image

(Where m and n are average values and represent positive numbers, m = 0.05 to 5 and n = 0.05 to 3.

[0010]

Embedded image

And base

[0012]

Embedded image

Are arranged in an arbitrary order. )
A triphenylmethane-type phenolic resin represented by
(2) an epoxy resin composition containing the epoxy resin, the phenol resin described in the above (1), (3) an epoxy resin composition described in the above (2) containing a curing accelerator,
(4) The epoxy resin composition according to the above (2) or (3), which contains an inorganic filler, and (5) the epoxy resin composition according to any one of the above (2), (3) and (4). A cured product obtained by curing a product is provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The triphenylmethane type phenolic resin of the present invention can be obtained, for example, by subjecting salicylaldehyde and p-hydroxybenzaldehyde to an excess phenol by a condensation reaction in the presence of an acid catalyst.

The charge ratio of salicylaldehyde to p-hydroxybenzaldehyde is usually 50: 5 by weight.
The ratio is 0 to 98: 2, preferably 60:40 to 95: 5. If the ratio of salicylaldehyde is too high, a large amount of phenol must be used in order to control the molecular weight distribution, and the volumetric efficiency is reduced. Conversely, if the proportion of p-hydroxybenzaldehyde is too high, the product becomes a crystalline compound having an extremely high melting point, making it difficult to take out the product from the reaction vessel. Hereinafter, salicylaldehyde and p-
Hydroxybenzaldehyde is collectively referred to as hydroxybenzaldehydes.

In the condensation reaction of hydroxybenzaldehydes and phenol, the ratio of both used is usually 1 mole of hydroxybenzaldehyde and usually 2 moles of phenol.
３０30 mol.

In the above condensation reaction, an acid catalyst is used.
Various acid catalysts can be used, but hydrochloric acid, sulfuric acid,
Inorganic or organic acids such as p-toluenesulfonic acid and oxalic acid, and Lewis acids such as boron trifluoride, anhydrous aluminum chloride and zinc chloride are preferred, and p-toluenesulfonic acid, sulfuric acid and hydrochloric acid are particularly preferred. The use amount of these acid catalysts is not particularly limited, but is usually 0.001 to 0.1 mol per 1 mol of hydroxybenzaldehydes.

The reaction may be carried out in the presence of various solvents from the viewpoint of controlling the reaction. When a solvent is used, methyl isobutyl ketone, toluene, xylene and the like are preferred. Next, if necessary, impurities such as a catalyst are removed by neutralization and washing with water.

After the completion of the reaction, the unreacted phenol, solvent and the like are removed according to a conventional method such as atmospheric distillation or vacuum distillation to obtain the triphenylmethane type phenol resin of the present invention.

Hereinafter, the epoxy resin composition of the present invention will be described. It contains the epoxy resin and the triphenylmethane type phenol resin of the present invention as a curing agent. The epoxy resin which can be used in the epoxy resin composition of the present invention includes a novolak type epoxy resin, a triphenylmethane type phenol resin of the present invention, and a triphenylmethane type such as a glycidyl etherified product of the compound represented by the formula (2). Epoxy resin, bisphenol A type epoxy resin,
Bisphenol F type epoxy resin, biphenyl type epoxy resin and the like can be mentioned. These epoxy resins may be used alone or in combination of two or more. Among these epoxy resins, a novolak-type epoxy resin, a triphenylmethane-type epoxy resin, and the like are preferable in order to better express the high heat resistance of the curing agent.

In the epoxy resin composition of the present invention, another curing agent can be used in combination with the triphenylmethane type phenol resin of the present invention. Examples of curing agents that can be used in combination include amine compounds, acid anhydride compounds,
Amide compounds, phenol compounds and the like can be used. Specific examples of the curing agent that can be used in combination include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, dicyandiamide, a polyamide resin synthesized from a dimer of linolenic acid and ethylenediamine, phthalic anhydride, and anhydride. Trimellitic acid, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, phenol novolak, aralkylene phenol resin, etc. And modified products thereof, imidazole, BF ₃ -amine complex, guanidine derivative and the like, but are not limited thereto. When these curing agents are used in combination, the proportion of the triphenylmethane-type phenol resin of the present invention in the total curing agent is preferably at least 30% by weight, particularly preferably at least 40% by weight.

The amount of the curing agent used in the epoxy resin composition of the present invention is preferably from 0.7 to 1.2 equivalents to 1 equivalent of the epoxy group of the epoxy resin. If the amount is less than 0.7 equivalents or more than 1.2 equivalents with respect to 1 equivalent of epoxy group, curing may be incomplete and good cured physical properties may not be obtained.

When the above curing agent is used, a curing accelerator may be used in combination. Specific examples of the curing accelerator that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2- (dimethylaminomethyl) phenol,
1,8-diaza-bicyclo (5,4,0) undecene-
Tertiary amines such as 7, phosphines such as triphenylphosphine, and metal compounds such as tin octylate. The curing accelerator is used in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the epoxy resin as required.

The epoxy resin composition of the present invention contains an inorganic filler if necessary. Specific examples of the inorganic filler that can be used include silica, alumina, and talc. The inorganic filler is used in the epoxy resin composition of the present invention in an amount of from 0 to 9;
An amount occupying 0% by weight is used if necessary. Further, the epoxy resin composition of the present invention, a silane coupling agent,
Various compounding agents such as a releasing agent such as stearic acid, palmitic acid, zinc stearate and calcium stearate, and a pigment can be added.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the components at a predetermined ratio. The epoxy resin composition of the present invention can be easily made into a cured product by a method similar to a conventionally known method. For example, an epoxy resin and a curing agent, and if necessary, a curing accelerator,
An extruder, a needle, if necessary, with an inorganic filler and a compounding agent.
The epoxy resin composition is thoroughly mixed using a mortar, roll, or the like until uniform, and the epoxy resin composition is melted and then molded using a casting or transfer molding machine. The cured product of the present invention can be obtained by heating at ~ 200 ° C for 2-10 hours.

Further, the epoxy resin composition of the present invention is dissolved in a solvent such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, and the like, and is used to prepare glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper, etc. A prepreg obtained by impregnating a substrate and drying by heating may be subjected to hot press molding to obtain a cured product. The solvent in this case is usually 10 to 70% by weight, preferably 1% by weight in the mixture of the epoxy resin composition of the present invention and the solvent.
An amount occupying 5 to 70% by weight, particularly preferably 15 to 65% by weight, is used.

[0027]

EXAMPLES The present invention will now be described more specifically with reference to examples and comparative examples. In the following, parts are by weight unless otherwise specified.

Example 1 109.8 parts of salicylaldehyde and p-hydroxybenzaldehyde were added to a flask equipped with a thermometer, a dropping funnel, a condenser, and a stirrer while purging with nitrogen gas.
2 parts, 1128 parts of phenol and 1.2 parts of p-toluenesulfonic acid were added, and the mixture was heated to 100 ° C. with stirring and reacted for 5 hours. After completion of the reaction, 12 parts of a 20% by weight aqueous solution of sodium dihydrogen phosphate was added for neutralization, and 300 parts of water was further added, followed by water washing.

The unreacted phenol is distilled off from the oil layer using an evaporator under heating and reduced pressure to obtain a triphenylmethane type phenol resin (A) of the present invention (m = 1.12 (average value) in the formula (1); (n = 0.13 (average value)) 274 parts were obtained. The obtained phenolic resin (A)
Has a softening point of 105.7 ° C. and a melt viscosity at 150 ° C. of 6.6 poise.

Example 2 In Example 1, the amount of salicylaldehyde was changed to 97.6.
Parts, the amount of p-hydroxybenzaldehyde was changed to 24.4 parts, and the triphenylmethane type phenol resin (B) of the present invention (m = 0.98 in the formula (1)) was similarly used.
(Average value), n = 0.25 (Average value)) 268 parts were obtained. The softening point of the obtained phenol resin (B) is 103.
The melt viscosity at 5 ° C. and 150 ° C. was 6.2 poise.

Examples 3-4, Comparative Example 1 As Example 3, a triphenylmethane type epoxy resin EP
Phenol resin (A) obtained in Example 1 as a curing agent for PN-502H (epoxy equivalent 170 g / eq, manufactured by Nippon Kayaku Co., Ltd.), and EPPN-5 as Example 4
02H, the phenol resin (B) obtained in Example 2 was used as a curing agent, and EPPN-5 was used as Comparative Example 1.
02H as a curing agent, a triphenylmethane-type phenol resin (C) represented by the formula (2) (having a hydroxyl equivalent of 9).
7 g / eq, a softening point of 106.5 ° C., and a melt viscosity at 150 ° C. of 8.0 poise), and triphenylphosphine (TPP) as a curing accelerator. At 70 ° C for 15
Kneading with a minute roll, 150 ° C, molding pressure 50kg / cm ²
Transfer molding for 180 seconds, then 160 ° C
For 2 hours and at 180 ° C. for 8 hours to prepare a test piece, and the glass transition point was measured under the following conditions. The results are shown in Table 1.

Glass transition point Dynamic viscoelasticity measuring device (DMA): Toyo Seiki Co., Ltd.
olograph-solid Heating rate: Measured as the maximum value of 2 ° C / min tan δ

[0033]

Table 1 Example 1 Example Comparative Example 3 4 1 Composition of formulation EPPN-502H 100 100 100 Phenolic resin (A) 57 Phenolic resin (B) 57 Phenolic resin (C) 57 TPP 11 11 Physical properties Glass transition point (℃) 288 290 285

From Table 1, it is clear that the cured product of the epoxy resin composition of the present invention shows a high glass transition point.

[0035]

The triphenylmethane-type phenolic resin of the present invention has excellent heat resistance despite its relatively low viscosity as compared with the conventionally used triphenylmethane-type phenolic resin. Giving things, molding materials,
It is extremely useful for a wide range of applications such as casting materials, laminate materials, paints, adhesives, resists, and the like.

Claims (5)

[Claims] (1) The following formula (1): (Where m and n are average values and represent positive numbers, and m = 0.0
5-5, n = 0.05-3. In addition, the group And the group Are arranged in any order. ) Triphenylmethane type phenolic resin represented by 2. An epoxy resin composition comprising the epoxy resin and the phenol resin according to claim 1. 3. The epoxy resin composition according to claim 2, further comprising a curing accelerator. 4. The epoxy resin composition according to claim 2, further comprising an inorganic filler. 5. A cured product obtained by curing the epoxy resin composition according to any one of claims 2, 3 and 4.