JP4407823B2 - Novel cyanate ester compound, flame retardant resin composition, and cured product thereof - Google Patents

Description

  The present invention relates to a novel cyanate ester compound, and further relates to a thermosetting resin composition containing the compound and a cured product thereof. The cyanate ester compound of the present invention can obtain a polymer material excellent in flame retardancy, heat resistance and low dielectric properties by polymerizing itself or copolymerizing with other resins. . Such a thermosetting resin composition includes an insulating material for electricity, a resin for resist, a resin for semiconductor encapsulation, an adhesive for printed wiring boards, a matrix resin for electrical laminates and prepregs, a build-up laminate material, and a fiber reinforced plastic. It can be used for a wide range of applications such as resin for resin, sealing resin for liquid crystal display panel, resin for color filter of liquid crystal, paint, various coating agents, and adhesives.

  Cyanate ester resins produce triazine rings upon curing, and due to their high heat resistance and excellent electrical properties, various functional polymer materials such as structural composite materials, adhesives, electrical insulating materials, and electrical and electronic parts have been used in the past. It is widely used as a raw material. However, in recent years, with the sophistication of required performance in these application fields, the physical properties required as a functional polymer material have become increasingly severe. Such physical properties include, for example, flame retardancy, heat resistance, low dielectric constant, low dielectric loss tangent, weather resistance, chemical resistance, low water absorption, high fracture toughness, and so on. Has not always been satisfied.

  For example, in the field of printed wiring board materials, as the communication frequency and clock frequency increase, the material is required to have a low dielectric constant and a low dielectric loss tangent, and cyanate resins having excellent dielectric properties are often used. It has become like this. At that time, from the viewpoint of ensuring safety against fire, it is necessary to impart flame retardancy, and bromine compounds having high flame retardancy are used. For example, brominated bisphenol A (for example, see Patent Document 1), glycidyl ether of brominated phenol novolak (for example, see Patent Document 2), brominated maleimides (for example, see Patent Document 3), monofunctional cyanate having halogen (For example, refer to Patent Document 4), addition type bromine compounds that are not reactive with cyanate ester compounds (for example, refer to Patent Document 5) are known.

  Although such a bromine compound has high flame retardancy, there is a risk of generating corrosive bromine and hydrogen bromide by thermal decomposition, and a material that does not contain a brominated flame retardant is required.

  Therefore, phosphorus-containing compounds, nitrogen, and sulfur-containing compounds have been studied as flame retardants that can replace bromine. For example, triphenyl phosphate and resorcinol bis (diphenyl phosphate) have been studied as phosphorus compounds that are often blended in epoxy resins. However, when these are blended in large quantities, they reduce heat resistance, moisture resistance, water absorption, and the like. There are many cases.

  In order to improve it, a method of adding a phosphorus compound having a phenolic hydroxyl group to a cyanate compound is known (see, for example, Patent Document 6, Patent Document 7, and Patent Document 8). Is concerned. Moreover, although melamine, guanidine, etc. are used as a nitrogen compound, the flame retardance was inadequate alone.

  On the other hand, metal hydroxides such as aluminum hydroxide and magnesium hydroxide can be cited as flame retardants, but the addition of metal hydroxides may lead to deterioration of dielectric properties, heat resistance, impact resistance and moldability. There is. In addition, for example, as used in epoxy resins, the use of a large amount of inorganic filler such as spherical fused silica reduces the flammable components and ensures flame retardancy, which increases the melt viscosity of the molding material. Further, there are concerns that the moldability and the wettability with the base material are reduced, leading to a decrease in adhesive strength and the deterioration of dielectric properties.

  In addition, antimony-based flame retardants such as antimony trioxide, which are widely used in combination with brominated epoxy resins, have problems such as deleterious substances and concern about chronic toxicity. From the above viewpoint, the flame retardancy of the thermosetting resin itself is required more than ever.

  In addition to flame retardancy, heat resistance, low dielectric constant, low dielectric loss tangent, weather resistance, chemical resistance, low water absorption, high fracture toughness, moldability, adhesion, etc. Attempts have been made. For example, a method for producing a cured product excellent in thermal stability by combining monocyanate and dicyanate (see, for example, Patent Document 9), a combination of a monofunctional cyanate ester compound and a polyfunctional cyanate ester compound has a low dielectric constant and low A method for achieving a dielectric loss tangent (see, for example, Patent Document 10) is disclosed.

  In addition, a method for producing a flame retardant cyanate ester cured resin composition having low hygroscopicity while achieving low dielectric constant and low dielectric loss tangent by adding a monofunctional cyanate ester containing halogen is described. (For example, refer to Patent Document 4). Although the patent describes cyanate esters over a wide range, an aromatic monofunctional cyanate ester having bromine as a functional group is an essential component in order to maintain flame retardancy, and cyanate ester resin alone is difficult. It has not succeeded in improving flammability.

In addition, an aromatic cyanate ester compound (for example, see Patent Document 11) containing at least two rings bonded by a group containing an unsaturated group is a fluorine-containing dicyanate compound (for example, see Patent Document 12). In addition, a method of making a flame retardant using a phenol novolac-type cyanate ester (for example, see Patent Document 13) is provided. However, in any case, there is no known example that is a cured product of a cyanate ester compound alone and practically has all of low dielectric properties, flame retardancy, and heat resistance.
Japanese Patent Publication No. 4-24370 JP-A-2-286723 JP-A-7-207022 JP-A-6-122863 JP 2000-95938 A Japanese Patent Laid-Open No. 2003-128928 JP 2003-128753 A JP 2003-128784 A JP-A-6-228308 JP-A-6-49238 Special Table 2002-531989 JP 63-250359 A Japanese Patent Laid-Open No. 2002-206048

  The present invention provides a novel cyanate ester compound, a curable resin composition, and a cured resin composition having excellent flame retardancy and low dielectric constant, low dielectric loss tangent, and high heat resistance. It is in providing the hardened | cured material which becomes.

As a result of intensive studies, the present inventors have found that the cyanate ester compound represented by the general formula (1), preferably the compounds represented by the general formulas (2) to (7), is excellent in flame retardancy and low. The inventors have found that a cured product having a dielectric constant, a low dielectric loss tangent, and a high heat resistance can be obtained, and have completed the present invention. That is, the present invention is as follows.
1. A cyanate ester compound represented by the general formula (1).

（式中、Ａｒ_２はフェニレン基、ナフチレン基又はビフェニレン基を表すが、Ａｒ_２がフェニレン基のとき、Ａｒ_１はナフチレン基又はビフェニレン基を表し、Ａｒ_２がナフチレン基又はビフェニレン基のとき、Ａｒ_１はフェニレン基、ナフチレン基又はビフェニレン基を表す。ａはＲ _ｘ の結合個数を表し、ｂはＲ _ｙ の結合個数を表す。Ａｒ _１ がフェニレン基のときａは３であり、Ａｒ _１ がナフチレン基のときａは５であり、Ａｒ _１ がビフェニレン基のときａは７である。Ｒ _ｘ は水素、炭素数１〜５のアルキル基、フェニル基、ナフチル基又はビフェニル基を表わし、同一の基でも異なる基でもよい。Ａｒ _２ がフェニレン基のときｂは４であり、Ａｒ _２ がナフチレン基のときｂは６であり、Ａｒ _２ がビフェニレン基のときｂは８である。Ｒ _ｙ は水素、炭素数１〜５のアルキル基、フェニル基、ナフチル基又はビフェニル基を表わし、同一の基でも異なる基でもよい。ｎは１から５０までの整数を示す。）
２． 式（２）で示される上記第１項記載のシアネートエステル化合物。

(In the formula, Ar ₂ represents a phenylene group, a naphthylene group or a biphenylene group, but when Ar ₂ is a phenylene group, Ar ₁ represents a naphthylene group or a biphenylene group, and Ar ₂ represents a naphthylene group or a biphenylene group, Ar ₁ represents a phenylene group, a naphthylene group, or a biphenylene group, a represents the number of bonds of R _x , b represents the number of bonds of R _y, a ₁ is 3 when Ar ₁ is a phenylene group, and Ar ₁ is naphthylene When a group is a, a is 5 and when Ar ₁ is a biphenylene group, a is 7. R _x represents hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, a naphthyl group or a biphenyl group, and the same group But a is b when good .Ar ₂ is a phenylene group or a different group 4, b when Ar ₂ is naphthylene group is 6, b when Ar ₂ is biphenylene group with 8 That .R _y represents hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, a naphthyl group or a biphenyl group, an integer of the same or a different group with a group. N is from 1 to 50.)
2. The cyanate ester compound of the said 1st term | claim shown by Formula (2).

（式中、Ｒ_１〜Ｒ_４は水素又は炭素数１〜５のアルキル基を表し、同一の基でも異なる基でも良い。ｎは１から５０までの整数を示す。芳香環の置換基は任意の位置を選択できる。）
３． 式（３）で示される上記第１項記載のシアネートエステル化合物。

(Wherein R _{1 to} R ₄ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent on the aromatic ring is arbitrary. Can be selected.)
3. The cyanate ester compound of the said 1st term | claim shown by Formula (3).

（式中、Ｒ_１〜Ｒ_４は水素又は炭素数１〜５のアルキル基を表し、同一の基でも異なる基でも良い。ｎは１から５０までの整数を示す。芳香環の置換基は任意の位置を選択できる。）
４． 式（４）で示される上記第1項記載のシアネートエステル化合物。

(Wherein R _{1 to} R ₄ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent on the aromatic ring is arbitrary. Can be selected.)
4). The cyanate ester compound according to the above item 1, represented by the formula (4):

（式中、Ｒ_１とＲ_２は水素又は炭素数１〜５のアルキル基を表し、同一の基でも異なる基でも良い。ｎは１から５０までの整数を示す。芳香環の置換基は任意の位置を選択できる。）
５． 式（５）で示される上記第２項記載のシアネートエステル化合物。

(In the formula, R ₁ and R ₂ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent of the aromatic ring is arbitrary. Can be selected.)
5). The cyanate ester compound of the said 2nd formula shown by Formula (5).

（式中、ｎは１から５０までの整数を示す。）
６． 式（６）で示される上記第３項記載のシアネートエステル化合物。

(In the formula, n represents an integer of 1 to 50.)
6). The cyanate ester compound of the said 3rd formula shown by Formula (6).

７． 式（７）で示される上記第４項記載のシアネートエステル化合物。

7). The cyanate ester compound of the said 4th formula shown by Formula (7).

（式中、ｎは１から５０までの整数を示す。）
８． 上記第１項〜第７項のいずれかに記載のシアネートエステル化合物と硬化剤を含有する熱硬化性樹脂組成物。
９． 上記第８項記載の熱硬化性樹脂組成物を硬化させてなる硬化物。

(In the formula, n represents an integer of 1 to 50.)
8). A thermosetting resin composition comprising the cyanate ester compound according to any one of Items 1 to 7 and a curing agent.
9. Hardened | cured material formed by hardening | curing the thermosetting resin composition of the said 8th term | claim.

  The cyanate ester compound of the present invention gives a cured product excellent in flame retardancy, has a low dielectric constant, a low dielectric loss tangent, and has a high glass transition temperature, and thus is extremely useful as a high-functional polymer material. It can be used for a wide range of applications such as electrical insulating materials, adhesives, laminated materials, resists, build-up laminated plate materials, etc. as materials excellent in heat and electricity.

Hereinafter, the present invention will be described in detail. In the cyanate ester compound represented by the general formula (1), Ar ₂ represents a phenylene group, a naphthylene group, or a biphenylene group. When Ar ₂ is a phenylene group, Ar ₁ represents a naphthylene group or a biphenylene group, and Ar ₂ represents In the case of a naphthylene group or a biphenylene group, Ar ₁ represents a phenylene group, a naphthylene group or a biphenylene group. Specific examples of Ar ₁ and Ar ₂ include 1,4-phenylene group, 1,3-phenylene group, 4,4′-biphenylene group, 2,4′-biphenylene group, 2,2′-biphenylene group, 2 , 3′-biphenylene group, 3,3′-biphenylene group, 3,4′-biphenylene group, 2,6-naphthylene group, 1,5-naphthylene group, 1,6-naphthylene group, 1,8-naphthylene group 1,3-naphthylene group, 1,4-naphthylene group and the like.

In cyanate compound represented by the general formula (1), R _x may be a different group in the same group. R _x represents hydrogen, an alkyl group, or an aryl group. Specific examples of R _x include a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an i-butyl group, a tert-butyl group, an isomer pentyl group as an alkyl group, and a phenyl group or an alkylphenyl group as an aryl group. , Naphthyl group, alkylnaphthyl group, biphenyl group, alkylbiphenyl group, and the like.

In cyanate compound represented by the general formula (1), R _y may be different groups in the same group. R _y represents hydrogen, an alkyl group, or an aryl group. Specific examples of R _y include a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an i-butyl group, a tert-butyl group, an isomer pentyl group as an alkyl group, and a phenyl group or an alkylphenyl group as an aryl group. , Naphthyl group, alkylnaphthyl group, biphenyl group, alkylbiphenyl group, and the like.

  In the cyanate ester compound represented by the general formula (1), n represents an integer of 1 to 50.

Of the cyanate ester compounds represented by the general formula (1), preferably the cyanate ester compounds represented by the formulas (2) to (4), more preferably the cyanate ester compounds represented by the formulas (5) to (7). It is. In the cyanate ester compound of the formula (2), R _{1 to} R ₄ represent hydrogen or an alkyl group, preferably an alkyl group having 1 to 4 carbon atoms, and may be the same group or different groups. n represents an integer of 1 to 50. Aromatic ring substituents can be selected at any position.

In the cyanate ester compound of the formula (3), R _{1 to} R ₄ represent hydrogen or an alkyl group, preferably an alkyl group having 1 to 4 carbon atoms, and may be the same group or different groups. n represents an integer of 1 to 50. Aromatic ring substituents can be selected at any position.

In the cyanate ester compound of the formula (4), R ₁ and R ₂ represent hydrogen or an alkyl group, preferably an alkyl group having 1 to 4 carbon atoms, and may be the same group or different groups. n represents an integer of 1 to 50. Aromatic ring substituents can be selected at any position.

  The production method of the compound represented by the general formula (1) and the compounds represented by the formulas (2) to (7) is not particularly limited, and may be produced by any existing method as cyanate synthesis.

  For example, general methods for synthesizing cyanate compounds are described in IAN HAMERTON, “Chemistry and Technology of Cyanate Esters Resins”, BLACKIE ACADEMIC & PROFESSIONAL. US Pat. No. 3,553,244 also provides a method of reacting in a solvent so that cyan halide is always present in excess in excess of the base in the presence of the base. In JP-A-7-53497, a method using a tertiary amine as a base and synthesizing it while using it in excess of cyan chloride is disclosed in JP-T-2000-501138 in a continuous plug flow method, in which trialkylamine and cyanogen halide are used. JP 2001-504835 discloses a method of treating tert-ammonium halide by-product with a cation and anion exchange pair when phenol and cyanogen halide are reacted in a non-aqueous solution of tert-amine. Is disclosed. In addition, in Patent No. 291054, a tertiary amine and a cyanogen halide are simultaneously added and reacted in the presence of a solvent capable of separating a phenol compound from water, followed by washing with water and separation from the resulting solution. A method for precipitation purification using a poor solvent for tertiary alcohols and hydrocarbons is described.

  For example, it can be obtained by reacting a phenol compound represented by the general formula (8) with cyanogen chloride in a solvent in the presence of a basic compound. In addition, a similar method is employed in which a salt of a phenol compound and a basic compound represented by the general formula (8) is formed in a solution containing water, and then a two-phase interface reaction with cyanogen chloride is performed. You can also.

（式中、Ａｒ_１、Ａｒ_２、Ｒ_ｘ、Ｒ_ｙ、ｎ、ａおよびｂは式（１）に同じ。）

(In the formula, Ar ₁ , Ar ₂ , R _x , R _y , n, a and b are the same as in formula (1).)

    Normally, as a cyanate ester synthesis procedure, a phenol compound represented by the general formula (8) is dissolved in an organic solvent, a basic compound such as a tertiary amine is added, and then reacted with excess cyanogen halide. . In this system, since cyan halide is always present in excess, it is said that imidocarbonate produced by reaction of phenolate anion with cyanate ester can be suppressed. However, since excess cyanogen halide and tertiary amine react to produce dialkylcyanamide, the reaction temperature must be kept at 10 ° C. or lower, preferably 0 ° C. or lower, more preferably −10 ° C. or lower.

    In addition to the above method, the order of pouring in the reaction can be arbitrarily selected. For example, after a phenol compound is dissolved in a solvent, a basic compound such as a tertiary amine and a cyanogen halide or a solution thereof may be dropped alternately or simultaneously. Further, a mixed solution of a phenol compound and a basic compound such as a tertiary amine and a cyanogen halide or a solution thereof can be simultaneously supplied. In either case, the reaction is a large exothermic reaction, but it is necessary to keep the reaction temperature at 10 ° C. or lower, preferably 0 ° C. or lower, more preferably −10 ° C. or lower for the purpose of suppressing side reactions.

    Any form of the reaction can be used, and the reaction may be performed in a batch system, a semi-batch system, or a continuous flow system.

    A basic compound such as a tertiary amine and a cyanogen halide are added in an amount of 0.1 to 8 times mol, preferably 1 to 3 times mol to the phenolic hydroxyl group of the phenol compound, and reacted. In particular, when there is a sterically hindered substituent at the ortho position of the hydroxyl group, the basic compound such as a tertiary amine and the required amount of cyanogen halide are increased as compared with the case where no substituent is present.

    As the cyanide halide to be used, cyan chloride, cyanogen bromide and the like can be used.

As the phenol compound to be used, in the phenol compound represented by the general formula (8), Ar ₂ represents a phenylene group, a naphthylene group, or a biphenylene group. When Ar ₂ is a phenylene group, Ar ₁ represents a naphthylene group or a biphenylene group. And when Ar ₂ is a naphthylene group or a biphenylene group, Ar ₁ represents a phenylene group, a naphthylene group or a biphenylene group. Specific examples of Ar ₁ and Ar ₂ include 1,4-phenylene group, 1,3-phenylene group, 4,4′-biphenylene group, 2,4′-biphenylene group, 2,2′-biphenylene group, 2 , 3′-biphenylene group, 3,3′-biphenylene group, 3,4′-biphenylene group, 2,6-naphthylene group, 1,5-naphthylene group, 1,6-naphthylene group, 1,8-naphthylene group 1,3-naphthylene group, 1,4-naphthylene group and the like. R _x may be a different group in the same group. R _x represents hydrogen, an alkyl group, or an aryl group. Specific examples of R _x include a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an i-butyl group, a tert-butyl group, an isomer pentyl group as an alkyl group, and a phenyl group or an alkylphenyl group as an aryl group. , Naphthyl group, alkylnaphthyl group, biphenyl group, alkylbiphenyl group, and the like. R _y may be a different group in the same group. R _y represents hydrogen, an alkyl group, or an aryl group. Specific examples of R _y include a methyl group, an ethyl group, an isopropyl group, an n-butyl group, an i-butyl group, a tert-butyl group, an isomer pentyl group as an alkyl group, and a phenyl group or an alkylphenyl group as an aryl group. , Naphthyl group, alkylnaphthyl group, biphenyl group, alkylbiphenyl group, and the like. N represents an integer from 1 to 50.

The compound of the general formula (8) can be obtained, for example, by the methods described in Japanese Patent Nos. 322834 and 2866747. Specifically, a method of reacting a bishalogenomethyl compound and a phenol compound represented by Ar ₂ — (CH ₂ X) ₂ with an acidic catalyst or non-catalyst, or Ar ₂ — (CH ₂ OR) ₂ The bis (alkoxymethyl) compound or the bis (hydroxymethyl) compound represented by Ar ₂ — (CH ₂ OH) ₂ and a phenol compound are reacted in an acidic catalyst.

    As the basic compound to be used, either an organic base or an inorganic base may be used, but when an organic solvent is used, an organic base having high solubility is preferable. Of these, tertiary amines with few side reactions are preferred. The tertiary amine may be any of alkylamine, arylamine, and cycloalkylamine, specifically, trimethylamine, triethylamine, methyldiethylamine, tripropylamine, tributylamine, methyldibutylamine, dinonylmethylamine, dimethylstearylamine, Examples include dimethylcyclohexylamine, diethylaniline, pyridine, and quinoline.

    Solvents used in the reaction include ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic solvents such as benzene, toluene, and xylene, diethyl ether, dimethyl cellosolve, diglyme, tetrahydrofuran, methyltetrahydrofuran, dioxane, and tetraethylene. Ether solvents such as glycol dimethyl ether, halogenated hydrocarbon solvents such as methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, alcohol solvents such as methanol, ethanol, isopropanol, methylsolvosolve, propylene glycol monomethyl ether, N, N -Aprotic polar solvents such as dimethylformamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidone, dimethyl sulfoxide; Nitrile solvents such as nitrile and benzonitrile, nitro solvents such as nitromethane and nitrobenzene, ester solvents such as ethyl acetate and ethyl benzoate, and hydrocarbon solvents such as cyclohexane can be used. 1 type or 2 types or more can be used in combination.

    As a post-treatment after the reaction, the hydrogen chloride salt of a basic compound such as a tertiary amine that is by-produced is usually filtered or removed by washing with water. In consideration of washing with water, it is preferable to use a solvent immiscible with water for the reaction. Moreover, in order to remove excess amines in the washing | cleaning process, the method of using acidic aqueous solutions, such as a thin hydrochloric acid, is also taken. In order to remove water from the sufficiently washed reaction solution, a drying operation can be performed using a general method such as sodium sulfate or magnesium sulfate.

    After these operations, a concentration, precipitation or crystallization operation is performed. At the time of concentration, since the cyanate ester compound has an unstable structure, a method of reducing the pressure while suppressing the temperature to 150 ° C. or lower is employed. In precipitation or crystallization, a solvent having low solubility can be used. For example, an ether solvent, a hydrocarbon solvent such as hexane, or an alcohol solvent is dropped into the reaction solution, or back-flowing is performed. Can be taken.

    In order to wash the obtained crude product, a method of washing the concentrate of the reaction solution and precipitated crystals with an ether solvent, a hydrocarbon solvent such as hexane, or an alcohol solvent can be employed. Further, the crystals obtained by concentrating the reaction solution can be re-dissolved and then recrystallized. In the case of crystallization, the reaction solution may be simply concentrated or cooled. A high-purity cyanate ester compound can be obtained by removing volatile components from the product thus obtained by a method such as drying under reduced pressure.

  Next, the curable resin composition of the present invention will be described. The curable resin composition is characterized by containing the cyanate ester compound of the present invention described above, and a cyanate ester compound other than the cyanate ester compound of the present invention, an epoxy resin, an oxetane resin, and / or a polymerization. It is also possible to add a compound having a possible unsaturated group.

  As the cyanate ester compound other than the cyanate ester compound of the present invention, generally known compounds can be used. For example, bisphenol A dicyanate, bisphenol F dicyanate, bisphenol M dicyanate, bisphenol P dicyanate, bisphenol E dicyanate, phenol novolac cyanate, cresol novolac cyanate, dicyclopentadiene novolac cyanate, tetramethylbisphenol F dicyanate, biphenol dicyanate Can be mentioned. These cyanate ester compounds can be used alone or in combination.

  When curing the cyanate ester compound, a known curing catalyst can be used. Examples thereof include metal salts such as zinc octylate, zinc naphthenate, cobalt naphthenate, copper naphthenate, and acetylacetone iron, and compounds having an active hydroxyl group such as phenol, alcohol, and amine.

  As the epoxy resin, generally known epoxy resins can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, xylene novolac type epoxy resin, triglycidyl isocyanurate, alicyclic epoxy resin, dicyclo Examples thereof include pentadiene novolac type epoxy resins, biphenyl novolac type epoxy resins, phenol aralkyl novolac type epoxy resins, and naphthol aralkyl novolak type epoxy resins. These epoxy resins can be used alone or in combination.

  As the oxetane resin, generally known oxetane resins can be used. For example, oxetane, 2-methyloxetane, 2,2-dimethyloxetane, 3-methyloxetane, alkyloxetane such as 3,3-dimethyloxetane, 3-methyl-3-methoxymethyloxetane, 3,3′-di (tri Fluoromethyl) perfluoxetane, 2-chloromethyloxetane, 3,3-bis (chloromethyl) oxetane, OXT-101 (trade name, manufactured by Toagosei Co., Ltd.), OXT-121 (trade name, manufactured by Toagosei Co., Ltd.) and the like. These oxetane resins can be used alone or in combination.

  When using an epoxy resin and / or an oxetane resin in the curable resin composition of the present invention, an epoxy resin curing agent and / or an oxetane resin curing agent can be used. As the epoxy resin curing agent, generally known ones can be used. For example, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl- Imidazole derivatives such as 2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, dicyandiamide, benzyldimethylamine, 4-methyl-N , N-dimethylbenzylamine and other amine compounds, and phosphine compounds include phosphonium phosphorus compounds. A known cationic polymerization initiator can be used as the oxetane resin curing agent. For example, commercially available products are Sanade SI60L, Sanade SI-80L, Sanade SI100L (manufactured by Sanshin Chemical Industry), CI-2064 (manufactured by Nippon Soda), Irgacure 261 (manufactured by Ciba Specialty Chemical), Adeka Optomer SP-170, Adekaoptomer SP-150 (manufactured by Asahi Denka), Syracure UVI-6990 (manufactured by UCC) and the like. The cationic polymerization initiator can also be used as an epoxy resin curing agent. These curing agents are used alone or in combination of two or more.

  As the compound having a polymerizable unsaturated group, generally known compounds can be used. For example, vinyl compounds such as ethylene, propylene, styrene, divinylbenzene, divinylbiphenyl, methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polypropylene glycol di (meth) acrylate, Mono- or polyhydric alcohol (meth) acrylates such as trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol Epoxy (meth) acrylates such as A-type epoxy (meth) acrylate and bisphenol F-type epoxy (meth) acrylate, benzocyclobutene resin, (bis) male Mid resin etc. are mentioned. These compounds having an unsaturated group can be used alone or in combination.

  When using the compound which has a polymerizable unsaturated group, a well-known polymerization initiator can be used as needed. As the polymerization initiator, generally known polymerization initiators can be used. For example, peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, di-t-butyl peroxide, diisopropyl peroxycarbonate, di-2-ethylhexyl peroxycarbonate, or azo such as azobisisobutyronitrile Compounds and the like.

  Furthermore, when producing the curable resin composition of the present invention, if necessary, a thermoplastic resin, an inorganic filler, a color pigment, an antifoaming agent, a surface conditioner, a flame retardant, an ultraviolet absorber, an antioxidant. Well-known additives such as a flow regulator can be added. Examples of inorganic fillers include silicas such as natural silica, fused silica, amorphous silica, white carbon, titanium white, aerosil, alumina, talc, natural mica, synthetic mica, kaolin, clay, aluminum hydroxide, barium sulfate, Examples include E-glass, A-glass, NE-glass, C-glass, L-glass, D-glass, S-glass, M-glass G20, and the like. The curable resin composition thus obtained is composed of an electrical insulating material, a resist resin, a semiconductor sealing resin, an adhesive for printed wiring boards, a build-up laminate material, a fiber reinforced plastic resin, and a liquid crystal display. It is useful for various applications such as panel sealing resins, liquid crystal color filter resins, paints, various coating agents, and adhesives.

The cured product of the present invention is obtained by curing the curable resin composition of the present invention obtained by the above-described method with heat. When the curing temperature is too low, curing does not proceed, and when it is too high, the cured product is deteriorated. Therefore, the curing temperature is preferably in the range of 150 ° C to 300 ° C.
Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not particularly limited to the following examples.

Example A1
Synthesis of cyanate ester of biphenyl novolak (formula (9): abbreviated as G65C)

ＯＨ基として１．１ｍｏｌを有する ビフェニルノボラック（日本化薬製ＫＡＹＡＨＡＲＤ−ＧＰＨＧ６５）及び１．６ｍｏｌトリエチルアミンを３−メチルテトラヒドロフラン９００ｍＬに溶解させた（溶液１）。２．２ｍｏｌの塩化シアンの塩化メチレン溶液２５００gに−１０℃で溶液1を１．５時間かけて滴下した。３０分撹拌した後、０．４ｍｏｌのトリエチルアミンと塩化メチレン１００ｇの混合溶液を滴下し、さらに３０分撹拌して反応を完結させた。トリエチルアミンの塩酸塩をろ別した後、得られたろ液を０．１Ｎ塩酸 １０００ｍＬにより洗浄した後、水１０００ｍＬによる洗浄を４回繰り返した。硫酸ナトリウムによる乾燥後、７５℃でエバポレートし、黄色固体の結晶を得た。得られた結晶をジエチルエーテル及びヘキサンにて洗浄した後、減圧乾燥することにより、ビフェニルノボッラクのシアネートエステルＧ６５Ｃを得た。ＩＲスペクトル測定により同定した。

Biphenyl novolak (KAYAHARD-GPHG65 manufactured by Nippon Kayaku Co., Ltd.) having 1.1 mol as an OH group and 1.6 mol triethylamine were dissolved in 900 mL of 3-methyltetrahydrofuran (solution 1). Solution 1 was added dropwise to 2500 g of methylene chloride solution of 2.2 mol of cyanogen chloride at −10 ° C. over 1.5 hours. After stirring for 30 minutes, a mixed solution of 0.4 mol of triethylamine and 100 g of methylene chloride was added dropwise, and the mixture was further stirred for 30 minutes to complete the reaction. After triethylamine hydrochloride was filtered off, the obtained filtrate was washed with 1000 mL of 0.1N hydrochloric acid, and then washed with 1000 mL of water four times. After drying with sodium sulfate, evaporation was performed at 75 ° C. to obtain a yellow solid crystal. The obtained crystals were washed with diethyl ether and hexane, and then dried under reduced pressure to obtain cyanate ester G65C of biphenylnovolak. It was identified by IR spectrum measurement.

Example B1-1
Cured product preparation Cyanate ester G65C of biphenyl novolac obtained in Example 1 was weighed in a eggplant-shaped flask at the ratio of Table 1, melted by heating to 150 ° C., degassed with a vacuum pump, and then added with zinc octylate for 1 minute. Stir and mix. This was poured into a mold made of a glass plate (120 mm × 120 mm × 5 mmt), a polyimide film (Kapton 200H: Toray DuPont), a fluororubber O-ring (S-100: Morisei), and 170 ° C. for 1 hour in an oven. It was cured by heating at 230 ° C. for 9 hours. After cooling, the polyimide film was removed by polishing to obtain a cured product of a cyanate ester compound.
The characteristics of the obtained cured product were evaluated by the following methods.
Glass transition temperature (Tg): determined by dynamic viscoelasticity measurement (DMA). Measurement was performed at a vibration frequency of 10 GHz.
Dielectric constant, dielectric loss tangent: determined by cavity resonance perturbation method.
Flame retardancy: A flame resistance test was performed based on UL94. However, the sample size was 10 mm × 70 mm × 1.5 mm.
The evaluation results of physical properties are shown in Table 1.

Example B1-2
The same procedure as in Example B1-1 was conducted except that 50 parts by weight of G65C obtained in Example 1 and bisphenol A dicyanate skylex manufactured by Mitsubishi Gas Chemical Co., Ltd. were mixed.
The evaluation results of the physical properties of the obtained cured product are shown in Table 1.

Comparative Example B1
The same procedure as in Example B1-1 was conducted except that Mitsubishi Gas Chemical's bisphenol A dicyanate skylex was used alone instead of G65C.
The evaluation results of the physical properties of the obtained cured product are shown in Table 1.

Comparative Example B2
The same procedure as in Example B1-1 was conducted except that Lonza phenol novolaccyanate PT30 was used instead of G65C.
The evaluation results of the physical properties of the obtained cured product are shown in Table 1.

Example A2
Synthesis of cyanate ester of biphenyl novolac monomer (formula (10): abbreviated as BPN-CN)

ＯＨ基として０．４ｍｏｌを有する ビフェニルノボラック単量体及び０．４ｍｏｌトリエチルアミンを３−メチルテトラヒドロフラン６００ｍＬに溶解させた（溶液１）。０．８ｍｏｌの塩化シアンの塩化メチレン溶液２２０gと３−メチルテトラヒドロフラン４００ｇを混合させた溶液に、−１０℃で溶液1を１．５時間かけて滴下した。３０分撹拌した後、０．３２ｍｏｌのトリエチルアミンと３−メチルテトラヒドロフラン８０ｇの混合溶液を滴下し、さらに３０分撹拌して反応を完結させた。トリエチルアミンの塩酸塩をろ別した後、得られたろ液を０．１Ｎ塩酸 １０００ｍＬにより洗浄した後、水１０００ｍＬによる洗浄を４回繰り返した。硫酸ナトリウムによる乾燥後、７５℃でエバポレートし、黄色固体の結晶を得た。得られた結晶をジエチルエーテル及びヘキサンにて洗浄した後、減圧乾燥することにより、ビフェニルノボラック単量体のシアネートエステルＢＰＮ−ＣＮを得た。ＩＲスペクトル測定により同定した。

Biphenyl novolak monomer having 0.4 mol as OH group and 0.4 mol triethylamine were dissolved in 600 mL of 3-methyltetrahydrofuran (solution 1). To a solution obtained by mixing 220 g of 0.8 mol of methylene chloride solution of cyanogen chloride and 400 g of 3-methyltetrahydrofuran, solution 1 was added dropwise at −10 ° C. over 1.5 hours. After stirring for 30 minutes, a mixed solution of 0.32 mol of triethylamine and 80 g of 3-methyltetrahydrofuran was added dropwise, and the mixture was further stirred for 30 minutes to complete the reaction. After triethylamine hydrochloride was filtered off, the obtained filtrate was washed with 1000 mL of 0.1N hydrochloric acid, and then washed with 1000 mL of water four times. After drying with sodium sulfate, evaporation was performed at 75 ° C. to obtain a yellow solid crystal. The obtained crystals were washed with diethyl ether and hexane and then dried under reduced pressure to obtain a cyanate ester BPN-CN of a biphenyl novolac monomer. It was identified by IR spectrum measurement.

Example A3
2,6-bis (4-cyanato-3,5-dimethylphenylmethyl) naphthalene (the following formula (11): hereinafter abbreviated as 26XNDC)

２，６―ビス（４−フェノキシ−３，５−ジメチルフェニルメチル）ナフタレン０．４ｍｏｌおよび１．３ｍｏｌトリエチルアミンを３−メチルテトラヒドロフラン６００ｍＬに溶解させた（溶液1）。２ｍｏｌの塩化シアンの塩化メチレン溶液２５００gとクロロホルム１０００ｇを混合させた液に−１０℃で溶液1を１．５時間かけて滴下した。３０分撹拌した後、０．６ｍｏｌのトリエチルアミンと塩化メチレン１００ｇの混合溶液を滴下し、さらに３０分撹拌して反応を完結させた。反応液をろ過した後、得られたろ液を０．１Ｎ塩酸 １０００ｍＬにより洗浄した後、水１０００ｍＬによる洗浄を４回繰り返した。硫酸ナトリウムによる乾燥後、７５℃にて濃縮操作をしていくうち、白色結晶が析出した。白色結晶をジエチルエーテル及びヘキサンにて洗浄した後、減圧乾燥することにより、白色結晶の２，６―ビス（４−シアナート−３，５−ジメチルフェニルメチル）ナフタレン（２６ＸＮＤＣ）を得た。ＩＲスペクトル測定により同定した。

2,6-bis (4-phenoxy-3,5-dimethylphenylmethyl) naphthalene 0.4 mol and 1.3 mol triethylamine were dissolved in 600 mL of 3-methyltetrahydrofuran (solution 1). Solution 1 was added dropwise at -10 ° C over 1.5 hours to a mixture of 2500 g of methylene chloride solution of 2 mol of cyanogen chloride and 1000 g of chloroform. After stirring for 30 minutes, a mixed solution of 0.6 mol of triethylamine and 100 g of methylene chloride was added dropwise, and the mixture was further stirred for 30 minutes to complete the reaction. After the reaction solution was filtered, the obtained filtrate was washed with 1000 mL of 0.1N hydrochloric acid, and then washed with 1000 mL of water four times. After drying with sodium sulfate, white crystals were precipitated during the concentration operation at 75 ° C. The white crystals were washed with diethyl ether and hexane and then dried under reduced pressure to obtain white crystals of 2,6-bis (4-cyanato-3,5-dimethylphenylmethyl) naphthalene (26XNDC). It was identified by IR spectrum measurement.

Example A4
Synthesis of cyanate ester of naphthol aralkyl (Formula (12): abbreviated as SN485CN)

ＯＨ基として０．４７ｍｏｌを有する ナフトールアラルキル（新日鐵化学製ＳＮ４８５Ｎ）及び０．７ｍｏｌトリエチルアミンをクロロホルム５００ｍＬに溶解させた（溶液1）。０．９３ｍｏｌの塩化シアンのクロロホルム溶液３００gに−１０℃で溶液1を１．５時間かけて滴下した。３０分撹拌した後、０．１ｍｏｌのトリエチルアミンとクロロホルム３０ｇの混合溶液を滴下し、さらに３０分撹拌して反応を完結させた。得られた反応液を０．１Ｎ塩酸 ５００ｍＬにより洗浄した後、水５００ｍＬによる洗浄を４回繰り返した。硫酸ナトリウムによる乾燥後、７５℃でエバポレートし、褐色の固形物を得た。得られた固形物をジエチルエーテル及びヘキサンにて洗浄した後、減圧乾燥することにより、ナフトールアラルキルのシアネートエステルを得た。ＩＲスペクトル測定により同定した。

Naphthol aralkyl (SN485N manufactured by Nippon Steel Chemical Co., Ltd.) having 0.47 mol as an OH group and 0.7 mol triethylamine were dissolved in 500 mL of chloroform (solution 1). Solution 1 was added dropwise to 300 g of 0.93 mol of cyanogen chloride in chloroform at −10 ° C. over 1.5 hours. After stirring for 30 minutes, a mixed solution of 0.1 mol of triethylamine and 30 g of chloroform was added dropwise, and the mixture was further stirred for 30 minutes to complete the reaction. The obtained reaction solution was washed with 500 mL of 0.1N hydrochloric acid, and then washed with 500 mL of water four times. After drying with sodium sulfate, evaporation was performed at 75 ° C. to obtain a brown solid. The obtained solid was washed with diethyl ether and hexane and then dried under reduced pressure to obtain cyanate ester of naphthol aralkyl. It was identified by IR spectrum measurement.

Example B2
The same procedure as in Example B1-1 was performed except that BPN-CN obtained in Example A2 was used instead of G65C.
Table 2 shows the evaluation results of the physical properties of the obtained cured product.

Example B3
The same procedure as in Example B1-1 was carried out except that 50 parts by weight of 26XNDC obtained in Example A3 and bisphenol A dicyanate skylex manufactured by Mitsubishi Gas Chemical Co. were used instead of G65C.
Table 2 shows the evaluation results of the physical properties of the obtained cured product.

Example B4
The same procedure as in Example B1-1 was performed except that SN485CN obtained in Example A4 was used instead of G65C.
Table 2 shows the evaluation results of the physical properties of the obtained cured product.

Claims (9)

A cyanate ester compound represented by the general formula (1).

(In the formula, Ar ₂ represents a phenylene group, a naphthylene group or a biphenylene group, but when Ar ₂ is a phenylene group, Ar ₁ represents a naphthylene group or a biphenylene group, and Ar ₂ represents a naphthylene group or a biphenylene group, Ar ₁ represents a phenylene group, a naphthylene group, or a biphenylene group, a represents the number of bonds of R _x , b represents the number of bonds of R _y, a ₁ is 3 when Ar ₁ is a phenylene group, and Ar ₁ is naphthylene When a group is a, a is 5 and when Ar ₁ is a biphenylene group, a is 7. R _x represents hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, a naphthyl group or a biphenyl group, and the same group But a is b when the good .Ar ₂ is a phenylene group or a different group 4, b when Ar ₂ is a naphthylene group is 6, the b when Ar ₂ is a biphenylene group 8 There .R _y represents hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, a naphthyl group or a biphenyl group, an integer of the same or a different group with a group. N is from 1 to 50.) The cyanate ester compound of Claim 1 shown by Formula (2).

(Wherein R _{1 to} R ₄ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent on the aromatic ring is arbitrary. Can be selected.) The cyanate ester compound of Claim 1 shown by Formula (3).

(Wherein R _{1 to} R ₄ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent on the aromatic ring is arbitrary. Can be selected.) The cyanate ester compound of Claim 1 shown by Formula (4).

(In the formula, R ₁ and R ₂ represent hydrogen or an alkyl group having 1 to 5 carbon atoms , and may be the same group or different groups. N represents an integer of 1 to 50. The substituent of the aromatic ring is arbitrary. Can be selected.) The cyanate ester compound of Claim 2 shown by Formula (5).

(In the formula, n represents an integer of 1 to 50.) The cyanate ester compound of Claim 3 shown by Formula (6).

The cyanate ester compound of Claim 4 shown by Formula (7).

(In the formula, n represents an integer of 1 to 50.)   The thermosetting resin composition containing the cyanate ester compound and hardening | curing agent in any one of Claims 1-7.   A cured product obtained by curing the thermosetting resin composition according to claim 8.