KR20150040752A - Thermosetting resin composition and cured product obtained from curing the same - Google Patents

Abstract

Provided is a thermosetting resin composition that can obtain a cured product having excellent heat resistance and moisture resistance while maintaining fluidity. The thermosetting resin composition comprises: novolak resin and epoxy resin as essential components, wherein the novolak resin is obtained by making phenols, unsaturated aldehydes and aromatic aldehydes react in the presence of an acidic catalyst.

Description

TECHNICAL FIELD [0001] The present invention relates to a thermosetting resin composition and a cured product obtained by curing the same. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a thermosetting resin composition and a cured product obtained by curing the same.

BACKGROUND ART A thermosetting resin composition comprising an epoxy resin and a phenol resin is used in various fields because of excellent heat resistance, adhesion, electrical insulation and the like. For example, a resin composition for an interlayer insulating material used for a resin composition for a printed circuit board, a printed board and a copper foil on which a resin is attached, a resin composition for a sealing material of an electronic part, a resist ink, a conductive paste (containing a conductive filler) , Composites and so on.

In the semiconductor encapsulant, there is an increasing demand for miniaturization, thinning, and miniaturization of products, and there is also a demand for improvement of heat resistance, moisture resistance, flame retardancy, and reduction of linear expansion coefficient. In recent years, lead-free solder is widely used in the mounting process due to environmental problems. Since lead-free solder has a melting point higher than that of a conventional solder, a high reflow temperature (for example, 245 ° C to 260 ° C) is required. In addition, since the IC chip is switched from Si to SiC, the temperature environment in which the semiconductor encapsulation and its surrounding materials are exposed is also increasing. Under such circumstances, the moisture absorbed in the semiconductor encapsulating material may expand or vaporize at high temperatures, resulting in cracking or peeling. In such a case, a phenomenon of lowering the reliability may occur. In particular, Demand is rising.

As one of the means for solving the problem, by increasing the amount of the filler used, it is possible to reduce the coefficient of linear expansion of the molded article, reduce the moisture absorption rate, and improve the flame retardancy. On the other hand, however, there is a problem in that the fluidity of the blend is lowered due to an increase in the amount of the blend, and the formability is deteriorated.

Patent Document 1 discloses that a novel phenolic resin having an alkylene group having 1 to 12 carbon atoms in its main chain is used as an epoxy curing agent to achieve low heat resistance when heated. However, a better low elastic modulus of the cured product is expected and insufficient from the viewpoint of heat resistance and moisture resistance.

Patent Document 2 discloses that a molded article excellent in heat resistance and water resistance can be obtained by using a biphenyl aralkyl-modified phenol resin as an epoxy curing agent. However, in a resin composition containing a biphenyl skeleton, the crosslinking density thereof is lowered, so that sufficient heat resistance can not be obtained and it is not necessarily high enough in terms of water resistance.

With regard to the heat resistance of the thermosetting resin composition, means for improving the crosslinking density is generally used. However, since the hydroxyl group concentration of the cured product of the epoxy resin and the phenol resin increases in proportion to the crosslinking density, have.

Japanese Patent Application Laid-Open No. 2013-57033 Japanese Patent Application Laid-Open No. 2007-63339

An object of the present invention is to provide a thermosetting resin composition which can obtain a cured product having excellent heat resistance and moisture resistance by containing a specific novolak resin.

That is, the present invention is represented by the following [1] to [11].

[1] A thermosetting resin composition comprising a novolak resin and an epoxy resin as essential components, wherein the novolak resin is a novolac resin obtained by reacting phenols, unsaturated aldehydes, and aromatic aldehydes in the presence of an acidic catalyst.

[2] The thermosetting resin composition according to [1], wherein the novolak resin is a novolac resin represented by the following general formula (1).

Wherein R ¹ to R ⁴ each independently represents any one of an alkyl group having 1 to 12 carbon atoms, a hydroxyl group and an alkoxy group having 1 to 12 carbon atoms, R ⁵ is an alkyl group having 1 to 12 carbon atoms, , An alkoxy group having 1 to 12 carbon atoms, or a halogen atom, a to e are each independently an integer of 0 to 3, X and Y each independently represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, And Z represents a residue obtained by removing two hydrogen atoms from a monocyclic or polycyclic aromatic hydrocarbon, and n and m are each independently an integer of 1 to 10)

[3] The process according to [

B- (OR) ₃ (2)

(Wherein, three R's each independently represent any one of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms)

, And an acid having a pKa of 5.0 or less at 25 占 폚. The thermosetting resin composition according to [1] or [2]

[4] The novolak resin according to any one of [1] to [4], wherein the novolak resin has an area ratio of GPC measurement of 45 to 90% of the total molecular weight of the novolac resin, the weight average molecular weight The thermosetting resin composition according to any one of [1] to [3], wherein the dispersion degree of the number average molecular weight is 1.5 or less.

[5] The thermosetting resin composition according to any one of [1] to [4], wherein the unsaturated aldehyde is at least one compound selected from croton aldehyde, acrolein, methacrolein and cinnamaldehyde.

[6] The thermosetting resin composition according to any one of [1] to [5], wherein the hydroxyl equivalent of the novolak resin is 0.6 to 1.2 with respect to an epoxy equivalent of 1.0 of the epoxy resin.

[7] The thermosetting resin composition according to any one of [1] to [6], further comprising a filler.

[8] A cured product obtained by curing the thermosetting resin composition according to any one of [1] to [7].

[9] A process for producing a novolac resin by reacting a phenol, an unsaturated aldehyde, and an aromatic aldehyde in the presence of an acid catalyst, and a process for producing a thermosetting resin composition having a novolak resin and an epoxy resin Way.

[10] The process according to [

B- (OR) ₃ (2)

(Wherein, three R's each independently represent any one of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms)

, And an acid having a pKa of 5.0 or less at 25 占 폚. The method for producing a thermosetting resin composition according to the above [9]

[11] The method for producing a thermosetting resin composition according to [9] or [10], wherein a filler is further added in the mixing step.

(Effects of the Invention)

According to the present invention, it is possible to provide a thermosetting resin composition which can obtain a cured product having excellent heat resistance and moisture resistance.

1 is a GPC chart of Novolak Resin A in Synthesis Example 1. Fig.
2 is a GPC chart of novolak resin C in Synthesis Example 3. Fig.

Hereinafter, the present invention will be described in detail.

[Thermosetting resin composition]

In the thermosetting resin composition of the present invention, a novolak resin and an epoxy resin are essential components, and the novolac resin is a novolak resin obtained by reacting phenols, unsaturated aldehydes, and aromatic aldehydes in the presence of an acidic catalyst.

≪ Novolac resin &

[Phenols]

The phenol used in the preparation of the novolac resin may be any as long as it is used in the production of a general phenol resin. Examples thereof include phenol, cresol, ethylphenol, xylenol, butylphenol, octylphenol, nonylphenol, phenylphenol, cyclohexyl Phenol, trimethylphenol, bisphenol A, catechol, resorcinol, hydroquinone, naphthol, pyrogallol, and the like, or a mixture of two or more thereof. Of these, phenol or cresol is preferably used because it is highly versatile and can be easily obtained from raw materials.

[Unsaturated aldehyde]

The unsaturated aldehyde used in the production of the novolak resin is a compound containing an unsaturated group and an aldehyde group. Specific examples thereof include acrolein, croton aldehyde, 2-methyl-2-butenal, 3-methyl-2-butenal, 2-pentenal, methacrolein, cinnamaldehyde, 2,4- Aldehyde, hexenal, heptenal, octenal, nonenal, undecenal, undecenal, dodecenal, 2-methylpentenal and alpha -hexylsynnamaldehyde may be used singly or in combination of two or more. Of these, it is preferable to use crotonaldehyde from the viewpoint of raw material availability and ease of reaction.

[Aromatic aldehyde]

The aromatic aldehyde used in the preparation of the novolac resin is a compound containing an aromatic group and an aldehyde group. Specific examples of the solvent include benzaldehyde, hydroxybenzaldehyde, dihydroxybenzaldehyde, methylbenzaldehyde, dimethylbenzaldehyde, trimethylbenzaldehyde, ethylbenzaldehyde, propylbenzaldehyde, butylbenzaldehyde, dibutylbenzaldehyde, dimethoxybenzaldehyde, dimethoxybenzaldehyde, Benzylaldehyde, tribromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, tetrabromobenzaldehyde, Benzylaldehyde, difluorobenzaldehyde, trifluorobenzaldehyde, tetrafluorobenzaldehyde, iodobenzaldehyde, diiodobenzaldehyde , Triiodobenzaldehyde, tetraiodobenzaldehyde, naphthalaldehyde, naphthalene dialdehyde, hydroxynaphthylaldehyde, anthracenecarboxyaldehyde, pyrencarboxyaldehyde, cyanobenzaldehyde, biphenyldicarboxyaldehyde, etc. may be used alone or in combination of two or more . Of these, it is preferable to use benzaldehyde from the viewpoint of raw material availability and ease of reaction.

The total amount of the unsaturated aldehyde and the aromatic aldehyde is preferably 0.1 to 1.0 mol, preferably 0.2 to 0.8 mol, more preferably 0.3 to 0.7 mol based on 1 mol of the total amount of the phenols.

When the total amount of the unsaturated aldehyde and the aromatic aldehyde is 0.1 mole or more and 1.0 mole or less, the number of remaining phenols is not increased, which is economical, and the resulting novolac resin has a molecular weight range described later.

[Acid catalyst]

The acid catalyst used in the production of the novolac resin may be any one which is used in the production of a general phenol resin. Examples thereof include oxalic acid, boric acid, phosphoric acid, para toluenesulfonic acid, hydrochloric acid, acetic acid, sulfuric acid, salicylic acid, Can be mixed with more than one kind. Among them, it is preferable to contain oxalic acid, boric acid, and paratoluenesulfonic acid in consideration of corrosiveness to the reaction equipment and yield.

From the viewpoint of obtaining a novolak resin having the properties described later, more preferably, an acid having a pKa of 5.0 or less and an acid of formula (2)

B- (OR) ₃ (2)

(Wherein, three R's each independently represent any one of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms)

Is preferably used at the same time.

The alkyl group having 1 to 10 carbon atoms represented by R may be linear or branched and may be branched or cyclic. Pentyl group, sec-pentyl group, tert-pentyl group, neopentyl group, hexyl group, isohexyl group, heptyl group, octyl group and decyl group.

Specific examples of the boron compound represented by the formula (2) include boric acid, trimethyl borate, triethyl borate, triisopropyl borate, and tributyl borate, and they may be used alone or in combination of two or more.

As the acid having a pKa of 5.0 or less at 25 캜, any acid may be used as long as it is used in the production of a general novolac resin, and examples thereof include hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, para toluenesulfonic acid, oxalic acid, It can be mixed and used. By using an acid having a pKa of 5.0 or less at 25 캜 as a catalyst, a novolak resin having the characteristics described later can be obtained. (PK _a1 = 1.27, pK _a2 = 4.27), phosphoric acid (pK _a1 = 2.12), and salicylic acid there may be mentioned (pKa = 2.97), tartaric acid (pK _a1 = 3.2) and the like.

The amount of the acidic catalyst to be used is preferably 0.1 to 20 parts by mass, preferably 0.1 to 10 parts by mass, and more preferably 0.2 to 5 parts by mass, based on 100 parts by mass of the phenols. Since the amount of the acidic catalyst used is not less than 0.1 parts by mass and not more than 20 parts by mass, a sufficient effect as a catalyst is obtained, and the phenomenon (molecular rearrangement) in which the molecular weight is increased during synthesis is suppressed to obtain a novolak resin have.

In the present invention, the novolac resin obtained by using phenol or cresol as the phenol, croton aldehyde as the unsaturated aldehyde, benzaldehyde as the aromatic aldehyde, oxalic acid, boric acid or para-toluenesulfonic acid as the acidic catalyst, .

[Preferable Structure of Novolak Resin]

The novolak resin is, for example, a compound represented by the following formula (1).

In the formulas, R ¹ to R ⁴ each independently represent any one of an alkyl group having 1 to 12 carbon atoms, a hydroxyl group, and an alkoxy group having 1 to 12 carbon atoms. From a practical point of view, each of R ¹ to R ⁴ is independently any one of an alkyl group having 1 to 6 carbon atoms, a hydroxyl group, and an alkoxy group having 1 to 6 carbon atoms, and any of an alkyl group having 1 to 3 carbon atoms and a hydroxyl group One is more preferable.

In the formula, R ⁵ represents any one of an alkyl group having 1 to 12 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 12 carbon atoms, and a halogen atom. From a practical point of view, R ⁵ is preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms, and is preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a hydroxyl group One is more preferable.

In the formulas, a to e are each independently an integer of 0 to 3, preferably 0 or 1.

In the formulas, X and Y each independently represent any one of a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, and a phenyl group. From the practical viewpoint, X and Y are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

In the formula, Z represents a residue obtained by removing two hydrogen atoms from a monocyclic or polycyclic aromatic hydrocarbon. And is preferably a residue obtained by removing two hydrogen atoms from benzene, naphthalene, or anthracene.

In the formulas, n and m are each independently an integer of 1 to 10. Preferably, n and m are each independently an integer of 1 to 5, more preferably n and m are independently integers of 1 to 3 from the viewpoint of achieving a desired melt viscosity.

In the formula (1), the units represented by n and m are shown as being coupled in series, but each unit may be connected at an intersection or at random.

R ¹ to R ⁴ are each independently any one of a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, and a hydroxyl group, and R ⁵ is a hydrogen atom , An alkyl group having 1 to 3 carbon atoms or a hydroxyl group, a to e each independently represent 0 or 1, X and Y each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, Z denotes benzene, naphthalene or The residues obtained by removing two hydrogen atoms from anthracene, n and m, are each independently 1 or 2, and more preferably n + m is 2 or 3.

It is preferable that the area ratio of the gel permeation chromatography (hereinafter referred to as " GPC ") in which the number average molecular weight of the novolak resin is 300 to 800 relative to the total molecular weight of the novolak resin is 30% , More preferably 45% or more, and still more preferably 60% or more.

The degree of dispersion (weight average molecular weight / number average molecular weight) of the weight average molecular weight and number average molecular weight in the total molecular weight of the novolak resin is preferably 2.5 or less, more preferably 1.5 or less, further preferably 1.3 or less Do. By setting the molecular weight in the above range, the desired melt viscosity can be obtained, the fluidity of the composition when mixed with the thermosetting resin composition can be maintained, and sufficient effects can be exhibited as a curing agent for the epoxy resin.

From the viewpoint of moldability when used as a curing agent for an epoxy resin, the novolac resin preferably has an area ratio of GPC measurement of not less than 45%, which has a number average molecular weight of from 300 to 800 to the total molecular weight of the novolak resin, The degree of dispersion of the weight average molecular weight and the number average molecular weight in the total molecular weight of the resin is preferably 1.5 or less. By using the novolak resin in the above-described range as a curing agent for an epoxy resin, it is possible to suppress the flexural modulus of elasticity at room temperature or at a high temperature (for example, 260 DEG C) It can be suitably used for various applications such as a composition.

The novolak resin is preferably 1,500 mPa · S or less, more preferably 1,000 mPa · S or less, and still more preferably 700 mPa · S or less based on the melt viscosity at 150 ° C. When the melt viscosity is 1500 mPa · S or less, when the compound is used as a curing agent for an epoxy resin, the fluidity of the compound is improved and a compound having excellent formability is obtained. The method of measuring the melt viscosity at 150 占 폚 is described in Examples.

The method of reacting the phenol and the aldehyde is not particularly limited. For example, there is a method in which the phenol, the aldehyde and the acid catalyst are added all at once, or the phenol and the acid catalyst are added, And a method of adding a flux.

The reaction temperature may be in the range of 30 to 130 占 폚, preferably 50 to 100 占 폚, and more preferably 60 to 80 占 폚.

Since the reaction temperature is 30 ° C or higher and 130 ° C or lower, the reaction proceeds at a proper reaction rate, unreacted phenols hardly remain, and generation of novolak resin of high molecular weight component is suppressed.

The reaction time is not particularly limited and may be adjusted depending on the amount of the aldehydes and the catalyst and the reaction temperature. For example, when the reaction is carried out for 6 to 10 hours, unreacted phenols hardly remain, and production of a novolak resin of a high molecular weight component is suppressed.

[Organic solvents]

In the reaction, it is also possible to use an organic solvent.

Examples of the organic solvent include alcohols such as propyl alcohol and butanol; glycols such as ethylene glycol and propylene glycol; alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, Methyl ethyl ketone, methyl ethyl ketone, methyl isobutyl ketone and the like, propyl acetate, butyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, Propylene glycol monomethyl ether acetate and the like, and ethers such as 1,4-dioxane, etc. may be used alone or in combination of two or more.

The organic solvent may be used in an amount of 0 to 1,000 parts by mass, preferably 10 to 100 parts by mass, more preferably 20 to 50 parts by mass, based on 100 parts by mass of the phenol.

After the reaction, the condensed water may be removed by distillation, or the remaining catalyst may be removed by washing with water if necessary.

Unreacted phenols and unreacted aldehydes may also be removed by distillation under reduced pressure or steam.

≪ Epoxy resin &

The epoxy resin used in the present invention is not particularly limited, and a known epoxy resin can be used. Specific examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin, resorcinol type epoxy resin, hydroquinone type epoxy resin, catechol type epoxy resin, dihydroxynaphthalene Epoxy resins derived from divalent phenols such as epoxy resins, biphenyl type epoxy resins and tetramethyl biphenyl type epoxy resins, phenol novolak type epoxy resins, cresol novolak type epoxy resins, triphenylmethane type epoxy resins, tetra A phenol aralkyl type epoxy resin, a biphenyl aralkyl type epoxy resin, a naphthol novolak type epoxy resin, a naphthol aralkyl type epoxy resin, a naphthol-phenol co-axial novolak type epoxy resin, Epoxy resin, naphthol-cresol coaxial novolak type epoxy resin, aromatic hydrocarbon formaldehyde An epoxy resin derived from tri- or higher-valent phenols such as a dehydrated resin-modified phenol resin type epoxy resin and a biphenyl-modified novolak type epoxy resin, and an epoxy resin modified with an organic phosphorus compound. Of these, biphenyl aralkyl type epoxy resins are preferred. These epoxy resins may be used alone or in combination of two or more.

[Mixing Ratio of Epoxy Resin to Novolak Resin]

The mixing ratio of the epoxy resin to the novolak resin is preferably in the range of 0.6 to 1.2, more preferably in the range of 0.7 to 1.1, still more preferably in the range of 1.0 .

<Curing accelerator>

In the thermosetting resin composition, a curing accelerator may be suitably used for the purpose of accelerating the curing reaction.

Examples of such a curing accelerator include organic acid metal salts such as imidazole, organic phosphorus compound, secondary, tertiary amine and tin octylate, Lewis acid and amine complex salt, and these may be used singly or in combination of two or more Can be used in combination.

As the imidazole compound, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-methylimidazole, 2-heptadecylimidazole, 4,5-diphenylimidazole, 2-methylimidazoline, 2-phenylimidazoline, 2- 2-isopropylimidazole, 2-heptadecylimidazoline, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl- Imidazoline, 2,4-dimethylimidazoline, 2-phenyl-4-methylimidazoline, and the like.

These imidazole-based compounds may be masked by a masking agent.

Examples of the masking agent include acrylonitrile, phenylene diisocyanate, toluidine isocyanate, naphthalene diisocyanate, methylenebisphenylisocyanate, and melamine acrylate.

Examples of the organophosphorous compound include ethylphosphine, propylphosphine, butylphosphine, phenylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, trioctylphosphine, triphenylphosphine, tricyclohexylphosphine, Triphenylphosphine / triphenylborane complex, tetraphenylphosphonium tetraphenylborate, and the like.

Examples of the secondary amine compound include morpholine, piperidine, pyrrolidine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, dibenzylamine, dicyclohexylamine, N-alkyl Arylamine, piperazine, diallylamine, thiazoline, thiomorpholine, and the like.

Examples of the tertiary amine compound include benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (diaminomethyl) phenol and the like.

In the thermosetting resin composition of the present invention, the total amount of the epoxy resin and the novolak resin is 5 to 50 parts by mass, preferably 10 to 30 parts by mass, more preferably 15 to 25 parts by mass, per 100 parts by mass of the thermosetting resin composition to be. It is possible to provide a thermosetting resin composition which can obtain a cured product having excellent heat resistance and moisture resistance while maintaining fluidity.

[Other formulation]

In the thermosetting resin composition of the present invention, various additives such as a filler, a thermosetting resin used as a modifier, a thermoplastic resin, a pigment, a silane coupling agent, a release agent and the like may be added according to the purpose, if necessary.

Examples of the filler include fillers such as fused silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, forsterite, stearate, spinel, titania, aluminum hydroxide, magnesium hydroxide And the like. The fused silica may be either crushed or spherical. However, in order to increase the content of the fused silica in the thermoplastic resin composition and to suppress the increase of the melt viscosity of the molding material, it is preferable to use a spherical one. In order to increase the content of the spherical silica in the thermoplastic resin composition, it is preferable to appropriately adjust the particle size distribution of the spherical silica. The content of the filler varies depending on the application and the desired characteristics. For example, when it is used for a semiconductor sealing material, it is preferable that the filler content is high in view of the coefficient of linear expansion and the flame retardancy. When the content is more than 65% , And particularly preferably about 80 to 90 mass%. When used for conductive paste or conductive film, a conductive filler such as silver powder or copper powder can be used.

As the thermosetting and thermoplastic resin used as the modifier, any of various known resins can be used, and examples thereof include phenoxy resin, polyamide resin, polyimide resin, polyetherimide resin, polyether sulfone resin, polyphenylene ether resin, A polyphenylene sulfide resin, a polyester resin, a polystyrene resin, a polyethylene terephthalate resin and the like may be used as long as they do not impair the effect of the present invention.

Examples of the silane coupling agent include silane coupling agents such as amino silane compounds, vinyl silane compounds, styrene silane compounds, and methacryl silane compounds.

Examples of the release agent include stearic acid, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, and carnauba wax.

[Method of producing thermosetting resin composition]

The process for producing a thermosetting resin composition according to the present invention comprises the steps of reacting a phenol, an unsaturated aldehyde and an aromatic aldehyde in the presence of an acidic catalyst to prepare a novolak resin, and a step of mixing the novolak resin and an epoxy resin as essential components Mixing process.

The phenols, unsaturated aldehydes, aromatic aldehydes, and acidic catalysts in the method for producing a thermosetting resin composition of the present invention are the same as those described in the above-mentioned thermosetting resin composition, so that the explanation thereof is omitted.

In the method for producing a thermosetting resin composition according to the present invention, various additives such as the above-mentioned curing accelerator, a thermosetting resin used as a filler and a modifying agent, and a thermoplastic resin, a pigment, a silane coupling agent, May be added.

The thermosetting resin and thermoplastic resin, pigment, silane coupling agent, and releasing agent used as a curing accelerator, filler, modifier, and the like are the same as those described above in the thermosetting resin composition, and therefore the description thereof is omitted.

In the method for producing a thermosetting resin composition according to the present invention, any one of the above-mentioned fillers may be added in the mixing step. As the filler, fused silica is preferable from the viewpoints of melt viscosity and heat resistance of the thermosetting resin composition.

The mixing method and the mixing order in the mixing step are not particularly limited, but it is possible to mix the novolak resin and the novolac resin by using a device such as a Sri One motor, a high shear mixer, a planetary mixer, a bead mill, An epoxy resin, a curing accelerator, and other compounding agents, if necessary, may be added in a batch or sequentially, followed by mixing. When mixing, they may be mixed while heating according to the softening point or melting point of the raw material.

[Example]

Hereinafter, the present invention will be described more specifically, but the present invention is not limited thereto.

(Synthesis Example 1)

100 g (0.92 mol) of orthocresol, 13 g (0.19 mol) of crotonaldehyde, 20 g (0.19 mol) of benzaldehyde, 1 g of boric acid and 1 g of oxalic acid (pKa = 1.04) were fed into a flask equipped with a stirrer, And reacted for 8 hours. Subsequently, the catalyst and the unreacted orthocresol were removed by washing four times with 100 g of pure water. Subsequently, the effluent was removed under a reduced pressure of 150 mmHg at 150 DEG C to obtain 70 g of novolak resin A. [

Fig. 1 shows a gel permeation chromatography (GPC) chart of Resin A. Fig. The abscissa represents the elution time (minutes).

From Fig. 1, it can be seen that the resin A has a low molecular weight component, that is, a component having a number average molecular weight of 300 to 600 is the main product.

(Synthesis Examples 2 to 7)

The reaction was carried out in the same manner as in Synthesis Example 1 except that the reaction conditions with the compounds shown in Table 1 were used to obtain novolak resins B to G.

2 shows a GPC chart of Resin C.

Table 1 shows values measured by the following analytical method for the novolak resins obtained in Synthesis Examples 1 to 7.

(1) Number-average molecular weight, weight-average molecular weight,

Was measured by Gel Permeation Chromatography (GPC).

Two columns of the "Shodex" (registered trademark) column of the organic solvent-based SEC (GPC) column manufactured by Showa Denko KK were used, and a differential refractometer "Shodex" Trademark) refractometer under the trade designation &quot; RI-71 &quot;. Tetrahydrofuran was used as a solvent, and the flow rate was measured at 1 ml / min.

The molecular weight was calculated in terms of polystyrene, and the content was calculated as a percentage of the total peak area.

The degree of dispersion was calculated by weight average molecular weight / number average molecular weight.

(2) Melt viscosity (mPa · S)

Research · This ICI viscometer was used and measured at 150 ° C.

(Examples 1 to 7 and Comparative Example 1)

(Curing accelerator) was added to the resin component obtained by melt kneading the novolak resins A to G in an amount equivalent to epoxy equivalent / hydroxyl equivalent = 1/1 with respect to 10 parts by mass of the epoxy resin at 110 占 폚, And an amount of the fused silica (inorganic filler) in an amount of 80% by mass in the composition were mixed in a two-step roll mill heated to 110 DEG C for 5 minutes to adjust the thermosetting resin composition. Table 2 shows the respective blends. In Comparative Example 1, biphenyl aralkyl type novolak resin as a novolac resin containing no aromatic aldehyde as a raw material; Resin BN (trade name &quot; MEH-7851 &quot;, manufactured by Meiwa Chemical Industries, Ltd., melting point: 440 mPa 占 폚 at 150 占 폚) was used.

The obtained thermosetting resin composition was pressure-molded in a mold at 150 占 폚 for 30 minutes under a pressure of 30 kg / cm2. Thereafter, the test pieces were cured at 180 캜 for 5 hours to produce a test piece having a length of 95 mm, a width of 10 mm, and a thickness of 4 mm.

The glass transition temperature, the water absorption rate, and the flexural modulus at 25 ° C and 260 ° C were evaluated by the following methods.

(3) Glass transition temperature

The glass transition temperature was measured by the TMA method using a trade name &quot; SSC / 5200 &quot; manufactured by Seiko Instruments Inc. (SII). The temperature rise rate was 10 占 폚 / min, the sample size width was 4 mm, the length was 10 mm, and the thickness was 8 mm.

(4) Absorption rate

The weight increase rate was measured after keeping the sample at 121 ° C and 100% humidity for 20 hours using an unsaturated high-rate life test apparatus "PC-422R8" (trade name) manufactured by Hirayama Seisakusho Co., Ltd.

(5) Flexural modulus

The results are shown in Table 2. The elastic modulus shown in Table 2 was 25 DEG C at room temperature and 260 DEG C at room temperature, Lt; 0 &gt; C.

In the formulation shown in Table 2, the following epoxy resin, triphenylphosphine and fused silica were used.

Epoxy resin: manufactured by Nippon Kayaku K.K., (biphenyl aralkyl type epoxy resin), trade name "NC-3000H"

Triphenylphosphine: manufactured by Wako Pure Chemical Industries, Ltd.

Fused silica: manufactured by Tatsumori Chemical Co., Ltd., trade name "MSR-2212"

Table 2 shows that the cured product of the thermosetting resin composition of the present invention exhibits a low glass transition temperature and a high glass transition temperature and a high melt viscosity in Comparative Examples. That is, it can be seen that the water absorption shows a lower value than that in the case of using novolak resin BN which is a conventional material, and the glass transition temperature exhibits the same or higher characteristics.

As described above, according to the present invention, it becomes possible to provide a thermosetting resin composition comprising a novolak resin which is an epoxy resin curing agent which imparts a cured product excellent in heat resistance and moisture resistance.

The thermosetting resin composition of the present invention has good heat resistance, moisture resistance, mechanical properties, electrical insulation, and adhesion to metals by the cured product. Specifically, the resin composition for a sealing material of an electronic part, the resin composition for a printed board, the resin composition for an interlayer insulating material used for a printed board and a copper foil with a resin, a conductive paste (containing a conductive filler) Composite materials and the like.

Claims (11)

A thermosetting resin composition comprising an novolac resin and an epoxy resin as essential components,
The novolak resin is a novolac resin obtained by reacting phenols, unsaturated aldehydes, and aromatic aldehydes in the presence of an acidic catalyst. The method according to claim 1,
Wherein the novolak resin is a novolac resin represented by the following general formula (1).

Wherein R ¹ to R ⁴ each independently represents any one of an alkyl group having 1 to 12 carbon atoms, a hydroxyl group and an alkoxy group having 1 to 12 carbon atoms, R ⁵ is an alkyl group having 1 to 12 carbon atoms, , An alkoxy group having 1 to 12 carbon atoms, or a halogen atom, a to e are each independently an integer of 0 to 3, X and Y each independently represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, And Z represents a residue obtained by removing two hydrogen atoms from a monocyclic or polycyclic aromatic hydrocarbon, and n and m are each independently an integer of 1 to 10) 3. The method according to claim 1 or 2,
The acid catalyst is represented by the formula (2)
B- (OR) ₃ (2)
(Wherein, three R's each independently represent any one of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms)
And an acid having a pKa of 5.0 or less at 25 占 폚. 3. The method according to claim 1 or 2,
Wherein the novolak resin has an area ratio of GPC measurement of 300 to 800 number-average molecular weight to the total molecular weight of the novolak resin of 45% or more, and a weight average molecular weight and a number average molecular weight Of the thermosetting resin composition is 1.5 or less. 3. The method according to claim 1 or 2,
Wherein the unsaturated aldehyde is at least one compound selected from croton aldehyde, acrolein, methacrolein, and cinnamaldehyde. 3. The method according to claim 1 or 2,
Wherein the hydroxyl group equivalent of the novolac resin is 0.6 to 1.2 with respect to the epoxy equivalent of 1.0 of the epoxy resin. 3. The method according to claim 1 or 2,
The thermosetting resin composition according to claim 1, further comprising a filler. A cured product obtained by curing the thermosetting resin composition according to any one of claims 1 to 3. A process for producing a novolak resin by reacting a phenol, an unsaturated aldehyde, and an aromatic aldehyde in the presence of an acidic catalyst,
A mixing step of mixing the novolac resin and an epoxy resin as essential components
Of the thermosetting resin composition. 10. The method of claim 9,
The acid catalyst is represented by the formula (2)
B- (OR) ₃ (2)
(Wherein, three R's each independently represent any one of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms)
, And an acid having a pKa of 5.0 or less at 25 占 폚. 2. The method for producing a thermosetting resin composition according to claim 1, 11. The method according to claim 9 or 10,
Wherein a filler is further added in the mixing step.

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