WO2015152007A1

WO2015152007A1 - Aromatic amine resin, maleimide resin, and curable resin composition and cured product thereof

Info

Publication number: WO2015152007A1
Application number: PCT/JP2015/059441
Authority: WO
Inventors: 窪木　健一; 昌照木村; 政隆中西
Original assignee: 日本化薬株式会社
Priority date: 2014-04-02
Filing date: 2015-03-26
Publication date: 2015-10-08
Also published as: CN106103534B; JP6429862B2; KR20160140586A; TW201605923A; JPWO2015152007A1; CN106103534A; TWI648303B; KR102254945B1

Abstract

The present invention addresses the problem of providing: an aromatic amine resin containing diphenylamine, which is a by-product, in a reduced amount; a maleimide resin induced from the aromatic amine resin; a curable resin composition produced using the aromatic amine resin and the maleimide resin; and a cured article which is produced by curing the curable resin composition and has excellent heat resistance, low hygroscopicity, low dielectric properties, flame retardancy and toughness. The aromatic amine resin according to the present invention is an aromatic amine resin containing a compound represented by formula (1), and wherein the compound is produced by reacting aniline with a bishalogenomethyl aralkyl derivative or an aralkyl alcohol derivative, wherein diphenylamine, which is a by-product, is contained in an amount of 1% by weight or less. (In the formula, X represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms; and n represents an average value and falls within the range from 1 to 10 inclusive (i.e., 1 ≤ n ≤ 10)).

Description

Aromatic amine resin, maleimide resin, curable resin composition and cured product thereof

The present invention relates to an aromatic amine resin and a maleimide resin derived therefrom, a curable resin composition using the same, and a cured product thereof, such as a semiconductor encapsulant, a printed wiring board, and a build-up laminate. -It is suitably used for lightweight high-strength materials such as electronic parts, carbon fiber reinforced plastics, and glass fiber reinforced plastics.

In recent years, the required characteristics of laminated boards carrying electrical / electronic components have been broadened and advanced due to the expansion of their fields of use. For example, in the past, semiconductor chips were mainly mounted on metal lead frames, but semiconductor chips with high processing capability such as CPUs are often mounted on laminates made of polymer materials. ing. As the speed of elements such as CPUs increases and the clock frequency increases, signal propagation delay and transmission loss become a problem, and the wiring board is required to have a low dielectric constant and a low dielectric loss tangent. At the same time, as the device speed increases, the heat generated by the chip has increased, and it has become necessary to increase the heat resistance. In recent years, mobile electronic devices such as mobile phones have become widespread, and precision electronic devices have been used and carried in the outdoor environment and in the immediate vicinity of the human body, so that they can withstand external environments (especially moisture and heat resistance). Tolerance is required. Furthermore, in the automobile field, computerization is rapidly progressing, and precision electronic devices are arranged near the engine, so that a higher level of heat resistance and moisture resistance is required. On the other hand, since it is used for automobiles and portable devices, safety such as flame retardancy is even more important, but the use of halogenated flame retardants has been avoided due to the recent increase in awareness of environmental issues. Therefore, there is an increasing need to impart flame retardancy without using halogen.

Conventionally, for example, a wiring board using BT resin, which is a resin in which a bisphenol A type cyanate ester compound and a bismaleimide compound described in Patent Document 1 are used in combination, has excellent heat resistance, chemical resistance, electrical characteristics, etc. Although it has been widely used as a wiring board, it needs to be improved in a situation where higher performance is required as described above.
In recent years, the weight reduction of airplanes, automobiles, trains, ships, etc. has been progressing due to the need for energy saving. In the field of vehicles, studies have been made in particular in the field of vehicles in which a metal material is replaced with a lightweight and high-strength carbon fiber composite material. For example, in Boeing 787, the weight is reduced by increasing the ratio of the composite material, and the fuel efficiency is greatly improved. In the automotive field, it is equipped with a propeller shaft made of composite material, but there is also a movement to make the vehicle body with composite material for luxury cars.
Conventionally, composite materials using epoxy resins such as bisphenol A diglycidyl ether and tetraglycidyl diaminodiphenylmethane and curing agents such as diaminodiphenylmethane and diaminodiphenylsulfone have been used. Therefore, characteristics that cannot be achieved by conventional resins have been demanded.

Japanese Patent Publication No.54-30440 Japanese Patent Publication No.8-16151 Japanese Patent No. 5030297

An object of the present invention is to provide an aromatic amine resin with a low content of diphenylamine as a by-product, a maleimide resin derived therefrom, a curable resin composition using these, and a heat resistance and low moisture absorption obtained by curing the resin. It is to provide a cured product having excellent properties, low dielectric properties, flame retardancy, and toughness.

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.

That is, the present invention provides the following [1] to [7].
[1] An aromatic amine resin containing a compound represented by the following formula (1) obtained by reacting aniline with a bishalogenomethylaralkyl derivative or an aralkyl alcohol derivative, and containing diphenylamine as a by-product An aromatic amine resin having a content of 1% by weight or less.

(In the formula, X represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. N is an average value and represents 1 ≦ n ≦ 10.)
[2] An aromatic amine resin containing a compound represented by the following formula (2) obtained by reacting aniline with a bishalogenomethylbiphenyl derivative or a biphenyl alcohol derivative, and containing diphenylamine as a by-product The aromatic amine resin according to [1], wherein is 1% by weight or less.

(In the formula, n is an average value and represents 1 ≦ n ≦ 10.)
[3] The aromatic amine resin according to [1] or [2], which has a softening point of 65 ° C. or lower.
[4] A maleimide resin obtained by reacting the aromatic amine resin according to any one of [1] to [3] with maleic acid or maleic anhydride.
[5] The maleimide resin according to [4], wherein the content of diphenylamine is 1% by weight or less.
[6] A curable resin composition comprising at least one of the aromatic amine resin according to any one of [1] to [3] and the maleimide resin according to [4] or [5].
[7] A cured product obtained by curing the curable resin composition according to [6].

By curing the curable resin composition containing the aromatic amine resin and maleimide resin of the present invention, a cured product having excellent properties such as high heat resistance, low moisture absorption, low dielectric properties, flame retardancy, and toughness is obtained. Can be provided. The curable resin composition of the present invention is a useful material for sealing electrical and electronic parts, circuit boards, carbon fiber composites, and the like.

The aromatic amine resin of the present invention contains a compound represented by the formula (1) or (2), and the content of diphenylamine by-produced during production is 1% by weight or less, preferably 0.5% by weight. In the following, it is more preferably controlled to 0.2% by weight or less.

The manufacturing method of the compound of Formula (1) or Formula (2) is not specifically limited. For example, Japanese Patent Publication No. 8-16151 and Japanese Patent No. 5030297 describe the reaction of aniline with a bishalogenomethylaralkyl derivative or an aralkyl alcohol derivative. A compound of formula (1) or formula (2) is obtained by reacting aniline with a bishalogenomethyl aralkyl derivative or aralkyl alcohol derivative.
Examples of bishalogenomethylaralkyl derivatives or aralkyl alcohol derivatives used include 1,4-bischloromethylbenzene, 1,3-bischloromethylbenzene, 1,2-bischloromethylbenzene, 1,4-bisbromomethylbenzene 1,3-bisbromomethylbenzene, 1,2-bisbromomethylbenzene, 1,4-dimethoxymethylbenzene, 1,3-dimethoxymethylbenzene, 1,2-dimethoxymethylbenzene, 1,4-diethoxymethyl Benzene, 1,3-diethoxymethylbenzene, 1,2-diethoxymethylbenzene, 1,4-dihydroxymethylbenzene, 1,3-dihydroxymethylbenzene, 1,2-dihydroxymethylbenzene, 2,6-dihydroxymethyl Naphthalene, 1,5-dihydroxymethyl Phthalene, 2,6-dimethoxymethylnaphthalene, 1,5-dimethoxymethylnaphthalene, 4,4′-bis (chloromethyl) biphenyl, 4,4′-bis (bromomethyl) biphenyl, 4,4′-bis (fluoromethyl) ) Biphenyl, 4,4′-bis (iodomethyl) biphenyl, 4,4′-dimethoxymethylbiphenyl, 4,4′-diethoxymethylbiphenyl, 4,4′-dipropoxymethylbiphenyl, 4,4′-diiso Examples include propoxymethyl biphenyl, 4,4′-diisobutoxymethyl biphenyl, 4,4′-dibutoxymethyl biphenyl, 4,4′-di-tert-butoxymethyl biphenyl, 4,4′-dihydroxymethyl biphenyl, and the like. These may be used alone or in combination of two or more. The amount of the bishalogenomethylaralkyl derivative or aralkyl alcohol derivative to be used is generally 0.05 to 0.8 mol, preferably 0.1 to 0.6 mol, per 1 mol of aniline used.

In the reaction, if necessary, an acidic catalyst such as hydrochloric acid, phosphoric acid, sulfuric acid, formic acid, zinc chloride, ferric chloride, aluminum chloride, p-toluenesulfonic acid, methanesulfonic acid and the like may be used. These may be used alone or in combination of two or more. The amount of the catalyst used is usually 0.1 to 0.8 mol, preferably 0.2 to 0.7 mol, relative to 1 mol of aniline used. If the amount is too large, the viscosity of the reaction solution may be too high and stirring may be difficult. If the amount is too small, the progress of the reaction may be delayed.
The reaction may be carried out using an organic solvent such as toluene or xylene, if necessary, or without solvent. For example, after adding an acidic catalyst to a mixed solution of aniline and a solvent, when the catalyst contains water, the water is removed from the system by azeotropic distillation. Thereafter, the bishalogenomethylaralkyl derivative or aralkyl alcohol derivative is added over 1 to 5 hours, preferably 2 to 4 hours at 40 to 100 ° C., preferably 50 to 80 ° C., and then the temperature is raised while removing the solvent from the system. The reaction is carried out at 180 to 240 ° C., preferably 190 to 220 ° C. for 5 to 30 hours, preferably 5 to 20 hours. After completion of the reaction, the acidic catalyst is neutralized with an aqueous alkaline solution, and then a water-insoluble organic solvent is added to the oil layer, and washing with water is repeated until the wastewater becomes neutral. Although not mentioned in Japanese Patent Publication No. 8-16151 and Japanese Patent No. 5030297, diphenylamine, which is a by-product at this stage, varies depending on the amount of catalyst, the ratio of raw materials used, temperature, time, etc. Usually 2 to 10% by weight is contained in the resin. Diphenylamine cannot be removed under conditions where aniline is distilled off. Diphenylamine can be removed by blowing steam or an inert gas such as a large amount of nitrogen gas under reduced pressure by heating at a temperature equal to or higher than the boiling point of aniline.

When diphenylamine is contained in the curable resin composition, for example, when used for a curing reaction with an epoxy resin, it becomes the terminal end of the molecular chain. The strength is significantly reduced. In addition, when diphenylamine is contained in the aromatic amine resin, diphenylamine remains as it is after maleimidation, and remains in the cured product as it is without contributing to the reaction. Decreases. Accordingly, the diphenylamine content is required to be 1% by weight or less, preferably 0.5% by weight or less, more preferably 0.2% by weight or less.

The softening point of the aromatic amine resin of the present invention is preferably 65 ° C. or lower, more preferably 60 ° C. or lower. When the softening point is higher than 65 ° C., the viscosity of the maleimidized resin becomes high, and it becomes difficult to impregnate carbon fibers or glass fibers. If the dilution solvent is increased to lower the viscosity, the resin may not adhere sufficiently.

The maleimide resin of the present invention can be obtained by reacting an aromatic amine resin containing the compound of formula (1) or formula (2) with maleic acid or maleic anhydride in the presence of a solvent and a catalyst. The methods described in Japanese Laid-Open Patent Publication No. 3-100016 and Japanese Patent Laid-Open No. 61-229863 may be employed. In that case, since it is necessary to remove the water produced | generated during reaction from the inside of a system, the solvent used by reaction uses a water-insoluble solvent. For example, aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane and n-hexane, ethers such as diethyl ether and diisopropyl ether, ester solvents such as ethyl acetate and butyl acetate, methyl isobutyl ketone and cyclopentanone However, it is not limited to these, and two or more kinds may be used in combination. In addition to the water-insoluble solvent, an aprotic polar solvent may be used in combination. Examples thereof include dimethyl sulfone, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, N-methylpyrrolidone, etc., and two or more kinds may be used in combination. When using an aprotic polar solvent, it is preferable to use a solvent having a higher boiling point than the water-insoluble solvent used in combination. The catalyst is not particularly limited, and examples thereof include acidic catalysts such as p-toluenesulfonic acid, hydroxy-p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid, and phosphoric acid.
For example, maleic acid is dissolved in toluene, an N-methylpyrrolidone solution of an aromatic amine resin containing the compound of formula (1) or formula (2) is added with stirring, and then p-toluenesulfonic acid is added and refluxed. The reaction is carried out while removing water produced under the conditions from the system.

Examples of the compound capable of crosslinking reaction with the aromatic amine resin which is one of the essential components of the curable resin composition of the present invention include epoxy group, maleimide group, aldehyde group, ketone group, acid anhydride group, isocyanate group, carbonyl The compound is not particularly limited as long as it is a compound having a functional group (or structure) capable of crosslinking reaction with an aromatic amine resin such as a group.
As a compound capable of crosslinking reaction with the maleimide resin which is one of the essential components of the curable resin composition of the present invention, amino group, cyanate group, phenolic hydroxyl group, alcoholic hydroxyl group, allyl group, acrylic group, methacryl group, The compound is not particularly limited as long as it is a compound having a functional group (or structure) capable of crosslinking with a maleimide resin such as a vinyl group or a conjugated diene group.
Since the amine compound and the maleimide compound undergo a crosslinking reaction, the aromatic amine resin and the maleimide resin of the present invention may be used in combination. The maleimide resin can be self-polymerized and can be used alone. Moreover, you may use together amine compounds other than the aromatic amine resin of this invention, or maleimide compounds other than the maleimide resin of this invention.
The content of the aromatic amine resin or maleimide resin of the present invention in the curable resin composition of the present invention is usually 10% by weight or more, preferably 15% by weight or more, more preferably 20% by weight or more. is there.

As the amine compound that can be blended in the curable resin composition of the present invention, a conventionally known amine compound can be used. Specific examples of the amine compound include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, m-xylenediamine, trimethylhexamethylenediamine, 2-methylpentamethylenediamine, diethylaminopropylamine, isophoronediamine, 1,3-bisaminomethyl. Cyclohexane, bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane, norbornenediamine, 1,2-diaminocyclohexane, diaminodiphenylmethane, metaphenylenediamine, diaminodiphenylsulfone, dicyandiamide, polyoxypropylene Examples include diamine, polyoxypropylene triamine, N-aminoethylpiperazine, and aniline / formalin resin. Not intended to be. These may be used alone or in combination of two or more. The compounding amount of the amine compound is preferably not more than 5 times, more preferably not more than 2 times the weight of the aromatic amine resin of the present invention.

As the maleimide compound that can be blended in the curable resin composition of the present invention, a conventionally known maleimide compound can be used. Specific examples of the maleimide compound include 4,4′-diphenylmethane bismaleimide, polyphenylmethane maleimide, m-phenylene bismaleimide, 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane, 3,3 '-Dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide 1,3-bis (3-maleimidophenoxy) benzene, 1,3-bis (4-maleimidophenoxy) benzene and the like, but are not limited thereto. These may be used alone or in combination of two or more. The blending amount of the maleimide compound is preferably 5 times or less, more preferably 2 times or less of the maleimide resin of the present invention by weight ratio.

The curable resin composition of the present invention can also contain a cyanate ester compound.
A conventionally well-known cyanate ester compound can be used as a cyanate ester compound which can be mix | blended with the curable resin composition of this invention. Specific examples of cyanate ester compounds include polycondensates of phenols and various aldehydes, polymers of phenols and various diene compounds, polycondensates of phenols and ketones, and polycondensations of bisphenols and various aldehydes. Examples include, but are not limited to, cyanate ester compounds obtained by reacting a product with cyanogen halide. These may be used alone or in combination of two or more.

Examples of the phenols include phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, and dihydroxynaphthalene.
Examples of the various aldehydes include formaldehyde, acetaldehyde, alkyl aldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, and cinnamaldehyde.
Examples of the various diene compounds include dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, and isoprene.
Examples of the ketones include acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, and benzophenone.
In addition, cyanate ester compounds described in Japanese Patent Application Laid-Open No. 2005-264154 are particularly preferable as cyanate ester compounds because they are excellent in low moisture absorption, flame retardancy, and dielectric properties.

An epoxy resin can also be mix | blended with the curable resin composition of this invention.
As an epoxy resin that can be blended in the curable resin composition of the present invention, any conventionally known epoxy resin can be used. Specific examples of epoxy resins include polycondensates of phenols and various aldehydes, polymers of phenols and various diene compounds, polycondensates of phenols and ketones, polycondensates of bisphenols and various aldehydes. And glycidyl ether epoxy resins obtained by glycidylation of alcohols, alicyclic epoxies such as 4-vinyl-1-cyclohexene diepoxide and 3,4-epoxycyclohexylmethyl-3,4′-epoxycyclohexanecarboxylate Examples of the resin include, but are not limited to, glycidylamine epoxy resins and glycidyl ester epoxy resins such as tetraglycidyldiaminodiphenylmethane (TGDDM) and triglycidyl-p-aminophenol. These may be used alone or in combination of two or more.
Further, a phenol aralkyl resin obtained by condensation reaction of phenols and the above-mentioned bishalogenomethyl aralkyl derivative or aralkyl alcohol derivative, and an epoxy resin obtained by dehydrochlorination reaction with epichlorohydrin are low hygroscopic, Since it is excellent in a flame retardance and a dielectric characteristic, it is especially preferable as an epoxy resin.

A phenol resin can also be mix | blended with the curable resin composition of this invention.
Any conventionally known phenol resin can be used as the phenol resin that can be blended in the curable resin composition of the present invention. Specific examples of phenolic resins include bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.), phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl Substituted polyhydroxybenzene, dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, alkyl aldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.) Phenols and various diene compounds (dicyclopentadiene, terpenes, vinyl Polymers with lohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.), phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.) Polycondensates with, phenols and aromatic dimethanols (benzenedimethanol, α, α, α ', α'-benzenedimethanol, biphenyldimethanol, α, α, α', α'-biphenyldimethanol Etc.), polycondensates of phenols and aromatic dichloromethyls (α, α'-dichloroxylene, bischloromethylbiphenyl, etc.), polycondensates of bisphenols and various aldehydes, and these These include modified products The present invention is not limited. These may be used alone or in combination of two or more.
In addition, a phenol aralkyl resin obtained by a condensation reaction of a phenol and the above bishalogenomethyl aralkyl derivative or aralkyl alcohol derivative is particularly preferable as a phenol resin because it is excellent in low moisture absorption, flame retardancy, and dielectric properties. .

The curable resin composition of the present invention may contain a compound having an acid anhydride group.
Any conventionally known compound having an acid anhydride group that can be blended in the curable resin composition of the present invention can be used. Specific examples of the compound having an acid anhydride group include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3, 4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, pyromellitic anhydride, 5- (2,5-dioxotetrahydrofuryl) -3-methyl- 3-cyclohexene-1,2-dicarboxylic acid anhydride, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, etc. Can be mentioned.
The compounds having an acid anhydride group can be used alone or in combination of two or more. In addition, the acid anhydride group and amine react to form an amic acid, but when heated at 200 ° C. to 300 ° C., an imide structure is formed by a dehydration reaction, resulting in a material with excellent heat resistance.

A curing catalyst (curing accelerator) can be blended with the curable resin composition of the present invention as necessary. For example, imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, triethylamine, Amines such as triethylenediamine, 2- (dimethylaminomethyl) phenol, 1,8-diaza-bicyclo [5.4.0] undecene-7, tris (dimethylaminomethyl) phenol, benzyldimethylamine, triphenylphosphine, Phosphines such as tributylphosphine and trioctylphosphine, tin octylate, zinc octylate, dibutyltin dimaleate, zinc naphthenate, cobalt naphthenate, tin oleate, zinc chloride, aluminum chloride Metal chlorides such as tin chloride, organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide, azo compounds such as azobisisobutyronitrile and azobisdimethylvaleronitrile, hydrochloric acid, sulfuric acid, phosphorus Examples include mineral acids such as acids, Lewis acids such as boron trifluoride, and salts such as sodium carbonate and lithium chloride. The amount of the curing catalyst is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, based on 100 parts by weight of the total curable resin composition.

The curable resin composition of the present invention can be made into a varnish-like composition (hereinafter simply referred to as varnish) by adding an organic solvent. Examples of the solvent used include amide solvents such as γ-butyrolactone, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylimidazolidinone, and tetramethylene sulfone. Sulfones, ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, propylene glycol monobutyl ether, ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone Aromatic solvents such as solvent, toluene, xylene and the like can be mentioned. The solvent is used in the range where the solid content concentration excluding the solvent in the obtained varnish is usually 10 to 80% by weight, preferably 20 to 70% by weight.

Furthermore, the curable resin composition of the present invention can contain known additives as required. Specific examples of additives that can be used include curing agents for epoxy resins, polybutadiene and modified products thereof, modified products of acrylonitrile copolymers, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide compounds, cyanate ester compounds , Silicone gel, silicone oil, inorganic fillers such as silica, alumina, calcium carbonate, quartz powder, aluminum powder, graphite, talc, clay, iron oxide, titanium oxide, aluminum nitride, asbestos, mica, glass powder, silane cup Coloring agents such as a surface treatment agent for a filler such as a ring agent, a release agent, carbon black, phthalocyanine blue, and phthalocyanine green can be used. The amount of these additives is preferably 1,000 parts by weight or less, more preferably 700 parts by weight or less, with respect to 100 parts by weight of the curable resin composition.

The method for preparing the curable resin composition of the present invention is not particularly limited, but each component may be mixed evenly or prepolymerized. For example, a maleimide resin and a cyanate ester compound are prepolymerized by heating in the presence or absence of a catalyst and in the presence or absence of a solvent. Similarly, the aromatic amine resin of the present invention and / or the maleimide resin of the present invention and, if necessary, an epoxy resin, an amine compound, a maleimide compound, a cyanate ester compound, a phenol resin, an acid anhydride compound and other additives are added. And may be prepolymerized. For mixing or prepolymerization of each component, for example, an extruder, a kneader, or a roll can be used in the absence of a solvent, and a reaction kettle with a stirring device can be used in the presence of a solvent.

A prepreg can be obtained by heating and melting the curable resin composition of the present invention to lower the viscosity and impregnating it with reinforcing fibers such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, and alumina fiber.
Moreover, a prepreg can also be obtained by impregnating the varnish into a reinforcing fiber and drying by heating.
The above prepreg is cut into a desired shape, laminated with copper foil as necessary, and then the curable resin composition is heated and cured while applying pressure to the laminate by a press molding method, autoclave molding method, sheet winding molding method, etc. Thus, an electric / electronic laminate (printed wiring board) and a carbon fiber reinforcing material can be obtained.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. In the text, “parts” and “%” represent “parts by weight” and “% by weight”, respectively. The softening point and melt viscosity were measured by the following methods.
・ Softening point: measured by a method according to JIS K-7234 ・ Melt viscosity: Viscosity at 150 ° C. by cone plate method ・ Diphenylamine content: measured by gas chromatography

Example 1
A flask equipped with a thermometer, a condenser, a Dean-Stark azeotropic distillation trap, and a stirrer was charged with 372 parts of aniline and 200 parts of toluene, and 146 parts of 35% hydrochloric acid was added dropwise at room temperature over 1 hour. After completion of the dropwise addition, the mixture was heated to cool and separate azeotropic water and toluene, and then only the organic layer of toluene was returned to the system for dehydration. Subsequently, 125 parts of 4,4′-bis (chloromethyl) biphenyl was added over 1 hour while maintaining the temperature at 60 to 70 ° C., and the reaction was further carried out at the same temperature for 2 hours. After completion of the reaction, toluene was distilled off while raising the temperature to bring the inside of the system to 195 to 200 ° C., and the reaction was carried out at this temperature for 15 hours. Then, with cooling, 330 parts of 30% aqueous sodium hydroxide solution was slowly added dropwise so that the system did not circulate vigorously, and the toluene distilled off at a temperature of 80 ° C. or lower was returned to the system and allowed to stand at 70 ° C. to 80 ° C. I put it. The separated lower aqueous layer was removed, and the reaction solution was washed with water until the washing solution became neutral. Subsequently, 173 parts of aromatic amine resin (a1) was obtained by distilling off excess aniline and toluene from the oil layer with a rotary evaporator under heating and reduced pressure (200 ° C., 0.6 KPa). Diphenylamine in the aromatic amine resin (a1) was 2.0%.
The obtained resin was again dripped in small amounts in place of steam blowing in a rotary evaporator under heating and reduced pressure (200 ° C., 4 KPa). As a result, 166 parts of aromatic amine resin (A1) was obtained. The aromatic amine resin (A1) obtained had a softening point of 56 ° C., a melt viscosity of 0.035 Pa · s, and diphenylamine of 0.1% or less.

Example 2
The same operation was performed except that 372 parts of aniline was changed to 457 parts in Example 1, and 181 parts of aromatic amine resin (a2) was obtained. Diphenylamine in the aromatic amine resin (a2) was 3.0%. The obtained resin was again dripped in small amounts in place of steam blowing in a rotary evaporator under heating and reduced pressure (200 ° C., 4 KPa). As a result, 166 parts of aromatic amine resin (A2) was obtained. The aromatic amine resin (A2) obtained had a softening point of 53 ° C., a melt viscosity of 0.025 Pa · s, and diphenylamine of 0.1% or less.

Example 3
The same operation was performed except that 372 parts of aniline was changed to 186 parts in Example 1, and 181 parts of aromatic amine resin (A3) was obtained. The aromatic amine resin (A3) obtained had a softening point of 64 ° C., a melt viscosity of 0.1 Pa · s, and diphenylamine of 0.16%.

Example 4
After adding 147 parts of maleic anhydride and 300 parts of toluene to a flask equipped with a thermometer, condenser, Dean-Stark azeotropic distillation trap, and stirrer, cooling and separating the water and toluene azeotropically heated. Then, only toluene which is an organic layer was returned to the system for dehydration. Next, a resin solution obtained by dissolving 195 parts of the aromatic amine resin (A1) obtained in Example 1 in 195 parts of N-methyl-2-pyrrolidone was added over 1 hour while maintaining the system at 80 to 85 ° C. It was dripped. After completion of the dropping, the reaction is carried out at the same temperature for 2 hours, 3 parts of p-toluenesulfonic acid is added, condensed water and toluene azeotroped under reflux conditions are cooled and separated, and only toluene which is an organic layer Was returned to the system and reacted for 20 hours while dehydrating. After completion of the reaction, 120 parts of toluene was added, and washing with water was repeated to remove p-toluenesulfonic acid and excess maleic anhydride, followed by heating to remove water from the system by azeotropy. Next, the reaction solution was concentrated to obtain a resin solution containing 70% of maleimide resin (M1). The diphenylamine content in the maleimide resin (M1) was 0.1% or less.

Comparative Example 1
When a similar operation was performed except that the aromatic amine resin (A1) was changed to the aromatic amine resin (a1) in Example 4, a 70% resin solution of the maleimide resin (m1) was obtained. The diphenylamine content in the maleimide resin (m1) was 1.4%.

Examples 5-6, Comparative Examples 2-3
Using the aromatic amine resins (A1) and (a1) obtained in Example 1, various epoxy resins were blended in the proportions (parts by weight) shown in Table 1, kneaded with mixing rolls, tableted, and transfer molded. A resin molded body was prepared and cured at 160 ° C. for 2 hours and further at 180 ° C. for 8 hours. When the composition was liquid at room temperature, each component was heated, melted and mixed in a metal container, poured into a mold as it was, and cured at 160 ° C. for 2 hours and further at 180 ° C. for 8 hours. The results of measuring the physical properties of the cured product thus obtained for the following items are shown in Table 1.
Glass transition temperature: Temperature measured by a dynamic viscoelasticity tester and tan δ is a maximum value.
Moisture absorption: Weight increase rate after 24 hours at 121 ° C./100%. The test piece is a disk having a diameter of 50 mm and a thickness of 4 mm.
-Izod impact test value: Measured in accordance with JIS K7110.

note)
(E1): NC-3000 (manufactured by Nippon Kayaku Epoxy equivalent 270 g / eq)
(E2): jER-828 (manufactured by JER, epoxy equivalent 185)
(A1), (a1): Aromatic amine resin synthesized in Example 1

Example 7, Comparative Example 4
50 parts of 2,2-bis (4-cyanatophenyl) propane was dissolved in 643 parts of the maleimide resin (M1) obtained in Example 4 and the maleimide resin (m1) solution obtained in Comparative Example 1. A prepolymer was obtained by pre-reaction at 10 ° C. for 10 hours. To this, 150 parts of the aforementioned epoxy resin (E2) and 2 parts of zinc octylate were added and mixed uniformly. The solution thus obtained was thinly applied on a glass plate and cured at 170 ° C. for 2 hours and 250 ° C. for 1 hour. The obtained cured product was pulverized, the particle size was adjusted to 42 mesion and 60 mesh pass, 5 parts each was collected and dispersed in 50 parts of ion exchange water, and a pressure cooker test was performed at 121 ° C. for 20 hours. Table 2 shows the results of removing the powder and measuring the electrical conductivity of the extracted water.

Example 8, Comparative Example 5
Using the aromatic amine resins (A1) and (a1) obtained in Example 1, blended in proportions (parts by weight) shown in Table 3, kneaded with mixing rolls, tableted, and then molded by transfer molding. It was prepared and cured at 160 ° C. for 2 hours and further at 180 ° C. for 8 hours. Table 3 shows the results of measuring the physical properties of the cured product thus obtained for the following items.
・ Flame retardancy test Flame retardant judgment: Conforms to UL94. The sample size was 12.5 mm wide × 150 mm long, and the thickness was 0.8 mm.
Afterflame time: Total afterflame time of 0.8mm test piece

note)
Filler: fused silica (manufactured by Tatsumori Industry Co., Ltd. MSR-2212)
Curing accelerator: Salicylic acid (manufactured by Tokyo Chemical Industry)

From Table 1, it can be inferred that the examples with less diphenylamine content have higher glass transition temperatures and Izod impact test values and stronger crosslink networks than the comparative examples. Also, from Table 2, the example of the cured maleimide resin derived from the aromatic amine resin having a low diphenylamine content has a lower electrical conductivity of the extracted water than the comparative example, and it can be used for electric / electronic parts. When used, it is considered that defects are unlikely to occur even in various usage environments. From Table 3, the example using the aromatic amine resin with less diphenylamine content has better flame retardancy and better thermal decomposition resistance than the comparative example, and when used in electrical / electronic parts, etc., safety Is considered high.

Although the invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application (Japanese Patent Application No. 2014-076160) filed on April 2, 2014, and is incorporated by reference in its entirety. Also, all references cited herein are incorporated as a whole.

Since the curable resin composition containing the aromatic amine resin and maleimide resin of the present invention is cured, the cured product is excellent in heat resistance, low moisture absorption, low dielectric properties, flame retardancy, and toughness. It is useful for use in electrical and electronic parts such as semiconductor encapsulants, printed wiring boards, build-up laminates, and lightweight high-strength materials such as carbon fiber reinforced plastic and glass fiber reinforced plastic.

Claims

An aromatic amine resin containing a compound represented by the following formula (1) obtained by reacting aniline with a bishalogenomethylaralkyl derivative or an aralkyl alcohol derivative,
An aromatic amine resin in which the content of diphenylamine as a by-product is 1% by weight or less.

(In the formula, X represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms. N is an average value and represents 1 ≦ n ≦ 10.)
An aromatic amine resin containing a compound represented by the following formula (2) obtained by reacting aniline with a bishalogenomethylbiphenyl derivative or a biphenyl alcohol derivative,
The aromatic amine resin according to claim 1, wherein the content of diphenylamine as a by-product is 1% by weight or less.

(In the formula, n is an average value and represents 1 ≦ n ≦ 10.)
The aromatic amine resin according to claim 1 or 2, which has a softening point of 65 ° C or lower.
A maleimide resin obtained by reacting the aromatic amine resin according to any one of claims 1 to 3 with maleic acid or maleic anhydride.
The maleimide resin according to claim 4, wherein the content of diphenylamine is 1% by weight or less.
A curable resin composition comprising at least one of the aromatic amine resin according to any one of claims 1 to 3 and the maleimide resin according to claim 4 or 5.
A cured product obtained by curing the curable resin composition according to claim 6.