JP7341828B2 - Curable resin compositions, dry films, copper foils with resin, cured products, and electronic components - Google Patents

Description

The present invention relates to a curable resin composition, a dry film, a resin-coated copper foil, a cured product, and an electronic component, particularly a thermosetting curable resin composition containing an epoxy resin, a dry film, a resin-coated copper foil, and a cured resin composition. Regarding products and electronic parts.

Thermosetting resin compositions containing epoxy resins have traditionally been used as materials for insulating electronic components such as printed wiring boards, and are usually subjected to various curing processes in order to impart various properties to the cured product. agent is used in combination with epoxy resin.

For example, Patent Document 1 discloses an epoxy resin composition containing an epoxy resin, a compound having an active ester group as a curing agent, a triazine-containing phenol resin, a maleimide compound, and a phenoxy compound. According to the epoxy resin composition of Patent Document 1, it is disclosed that the obtained cured product exhibits high adhesion to plated conductors and can achieve an insulating layer with a low coefficient of linear expansion.

Patent No. 5396805

However, in addition to high adhesion to plated conductors, curable resin compositions for forming insulating layers of electronic components are required to impart high heat resistance to the cured product from the viewpoint of reliability. Furthermore, in recent years, with the adoption of high-speed communication, that is, with the increase in frequency, transmission loss has been increasing, so materials for electronic components are required to have a low dielectric loss tangent that can suppress transmission loss.

However, conventionally, it has been relatively easy to improve any one of the properties using a curable resin composition, but it has been difficult to uniformly improve all the properties. For example, epoxy resin is a component that contributes to the strength of the cured product and high adhesion to plated conductors, but depending on the amount of epoxy resin blended, it may increase the dielectric loss tangent of the cured product or reduce its adhesion to plated conductors. Studies by the inventors have revealed that it is difficult to simultaneously satisfy these characteristics.

In view of the above problems, an object of the present invention is to provide a thermosetting resin composition capable of obtaining a cured product having high heat resistance, low dielectric loss tangent, and high adhesion to a conductor, and a resin layer obtained from the composition. Our objective is to provide dry films, resin-coated copper foils, cured products, and electronic components.

The object of the present invention is to
(A) an epoxy resin;
(B) a compound having an active ester group;
(C) an aminotriazine skeleton-containing additive;
(D) an inorganic filler;
A curable resin composition containing,
It has been found that (C) the aminotriazine skeleton-containing additive can be achieved by a curable resin composition having a melting point measured according to JIS K6220.

Further, the curable resin composition of the present invention has a ratio of (A) total amount of epoxy groups in the epoxy resin/(B) total amount of active ester groups in the compound having active ester groups from 0.2 to 0.6. It is preferable that there be.

Furthermore, in the curable resin composition of the present invention, the mass ratio of (C) the aminotriazine skeleton-containing additive to the total amount of (A) the epoxy resin and (B) the compound having an active ester group, in terms of solid content, is It is preferably 0.001 or more and 0.100 or less.

Moreover, it is preferable that the aminotriazine skeleton-containing additive (C) further has a hydrolyzable silyl group or silanol group.

Further, the solubility of (C) the aminotriazine skeleton-containing additive in an organic solvent selected from the group consisting of methyl ethyl ketone, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate is 5 g/100 g-organic solvent or more at 20°C. It is preferable.

Further, the solubility of the aminotriazine skeleton-containing additive (C) in an epoxy resin having an epoxy equivalent of 500 or less is preferably 5 phr or more at 110°C.

Moreover, it is preferable that the inorganic filler (D) is included in a range of 50% by mass or more and 90% by mass or less, when the solid content in the curable resin composition is 100% by mass.

Furthermore, the object of the present invention is to provide a dry film having the above-mentioned curable resin composition as a resin layer;
A resin-coated copper foil comprising the above-mentioned curable resin composition as a resin layer on a copper foil or a carrier-coated copper foil;
The present invention is also achieved by a cured product obtained by curing the curable resin composition of the present invention, a resin layer of a dry film, or a resin layer of a resin-coated copper foil, and an electronic component characterized by having this cured product. I can do it.

According to the curable resin composition of the present invention, the obtained cured product has high heat resistance, low dielectric loss tangent, and high adhesion to conductors. Further, a dry film having a resin layer obtained from the curable resin composition of the present invention, a resin-coated copper foil having a resin layer obtained from the curable resin composition of the present invention, a curable resin composition of the present invention, a dry film having a resin layer obtained from the curable resin composition of the present invention, A cured product of a resin layer of a film or a resin layer of a resin-coated copper foil, and an electronic component containing this cured product also have high heat resistance, low dielectric loss tangent, and high adhesion to conductors.

<Curable resin composition>
The curable resin composition of the present invention is
(A) an epoxy resin;
(B) a compound having an active ester group;
(C) an aminotriazine skeleton-containing additive;
(D) an inorganic filler;
and (C) the aminotriazine skeleton-containing additive has a melting point measured according to JIS K6220.

[(A) Epoxy resin]
The curable resin composition of the present invention includes (A) an epoxy resin. (A) The epoxy resin is a resin having an epoxy group, and any conventionally known resin can be used, preferably a bifunctional epoxy resin having two epoxy groups in the molecule, or a bifunctional epoxy resin having three epoxy groups in the molecule. Examples include polyfunctional epoxy resins. Note that a hydrogenated epoxy resin may also be used. Furthermore, the epoxy resin (A) may be one or more of solid epoxy resins, semi-solid epoxy resins, and liquid epoxy resins. In this specification, solid epoxy resin refers to an epoxy resin that is solid at 40°C, semi-solid epoxy resin refers to an epoxy resin that is solid at 20°C, liquid at 40°C, and liquid epoxy resin. refers to an epoxy resin that is liquid at 20°C. The determination of liquid state is made in accordance with the "Method for Confirming Liquid State" in Attachment 2 of the Ministerial Ordinance on Testing and Properties of Dangerous Substances (Ministry of Home Affairs Ordinance No. 1 of 1989). For example, the method described in paragraphs 23 to 25 of JP-A No. 2016-079384 is used.

In the present invention, it is preferable that the epoxy resin (A) contains at least one of a trifunctional or higher functional liquid epoxy resin and a trifunctional or higher functional semisolid epoxy resin. When a trifunctional or higher functional liquid epoxy resin or a trifunctional or higher functional semisolid epoxy resin is included, the glass transition temperature can be improved while maintaining the dielectric loss tangent low.

Examples of solid epoxy resins include EPICLON HP-4700 (naphthalene type epoxy resin) manufactured by DIC, EPICLON EXA4700 (tetrafunctional naphthalene type epoxy resin) manufactured by DIC, and NC-7000L (polyfunctional solid epoxy containing naphthalene skeleton) manufactured by Nippon Kayaku Co., Ltd. (resin), naphthalene type epoxy resin such as ESN-475V manufactured by Nippon Steel Chemical Co., Ltd.; condensation product of phenols and aromatic aldehyde having a phenolic hydroxyl group such as EPPN-502H (trisphenol epoxy resin) manufactured by Nippon Kayaku Co., Ltd. Epoxidized product (trisphenol type epoxy resin); dicyclopentadiene aralkyl type epoxy resin such as EPICLON HP-7200H (dicyclopentadiene skeleton-containing polyfunctional solid epoxy resin) manufactured by DIC; NC-3000H, NC manufactured by Nippon Kayaku Co., Ltd. Biphenylaralkyl epoxy resins such as -3000L (polyfunctional solid epoxy resin containing biphenyl skeleton); Novolak epoxy resins such as EPICLON N660, EPICLON N690 manufactured by DIC, EOCN-104S manufactured by Nippon Kayaku; YX- manufactured by Mitsubishi Chemical Corporation Biphenyl-type epoxy resins such as 4000; phosphorus-containing epoxy resins such as TX0712 manufactured by Nippon Steel & Sumikin Chemical; tris(2,3-epoxypropyl) isocyanurate such as TEPIC manufactured by Nissan Chemical Co., Ltd., and the like. By including a solid epoxy resin, the glass transition temperature of the cured product becomes high and it has excellent heat resistance. Among solid epoxy resins, epoxy resins with a skeleton in which aromatic compounds, phenol, and naphthol are connected by methylene chains, such as ESN-475V and NC3000H, can be used to obtain cured products with higher Tg and lower dielectric loss tangent. is preferred.

Semi-solid epoxy resins include EPICLON860, EPICLON900-IM, EPICLON EXA-4816, EPICLON EXA-4822 manufactured by DIC, EPOTOTO YD-134 manufactured by Toto Kasei, jER834, jER872 manufactured by Mitsubishi Chemical, and E manufactured by Sumitomo Chemical. LA-134 Bisphenol A type epoxy resins such as; naphthalene type epoxy resins such as EPICLON HP-4032 manufactured by DIC; phenol novolac type epoxy resins such as EPICLON N-740 manufactured by DIC; aromatic amino epoxy resins such as jER604 manufactured by Mitsubishi Chemical Corporation, etc. can be mentioned. By containing the semi-solid epoxy resin, the cured product has a high glass transition temperature (Tg), a low coefficient of linear thermal expansion (CTE), and has excellent crack resistance. By including the semi-solid epoxy resin, the dry film has excellent storage stability and can prevent cracking and peeling.

Liquid epoxy resins include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol AF epoxy resin, phenol novolak epoxy resin, tert-butyl-catechol epoxy resin, glycidylamine epoxy resin, and aminophenol epoxy resin. Examples include aromatic aminoepoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, etc. By including a liquid epoxy resin, the flexibility of the dry film can be improved.

As for the epoxy resin, it is preferable to use a solid epoxy resin together with at least one of a liquid epoxy resin and a semi-solid epoxy resin. Furthermore, a solid epoxy resin, a liquid epoxy resin, and a semi-solid epoxy resin may be used together.

(A) Epoxy resins may be used alone or in combination of two or more. (A) The blending amount of the epoxy resin is 40% by mass or less, since a cured product with a lower coefficient of thermal expansion and lower hygroscopicity is obtained when the solid content in the curable resin composition is 100% by mass. It is preferably at most 35% by mass, more preferably at most 30% by mass, particularly preferably at most 20% by mass. Further, from the viewpoint of curability, the lower limit is preferably 1% by mass or more, more preferably 3% by mass or more.

In this specification, the solid content in the resin composition means components excluding organic solvents.

The curable resin composition of the present invention may contain thermosetting resins other than (A) epoxy resins within a range that does not impair the effects of the present invention, such as isocyanate compounds, blocked isocyanate compounds, amino resins, Known and commonly used thermosetting resins such as benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional oxetane compounds, episulfide resins, and maleimide resins can be used.

[(B) Compound having active ester group]
The curable resin composition of the present invention contains (B) a compound having an active ester group. (B) A compound having an active ester group is a compound that is blended into the curable resin composition of the present invention as a curing agent for A) an epoxy resin, and is a compound having two or more active ester groups in one molecule. It is preferable that there be. A compound having an active ester group can generally be obtained by a condensation reaction between a carboxylic acid compound and a hydroxy compound. Among these, compounds having an active ester group obtained by using a phenol compound or a naphthol compound as the hydroxy compound are preferred. Examples of phenolic compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol , dicyclopentadienyl diphenol, phenol novolak, and the like. Further, (B) the compound having an active ester group may be of the naphthalene diol alkyl/benzoic acid type. (B) The compound having an active ester group may be used alone or in combination of two or more. (B) The compound having an active ester group is preferably one having a benzene, α-naphthol, β-naphthol, or dicyclopentadiene skeleton.

(B) The upper limit of the compounding amount of the compound having an active ester group is preferably 50% by mass or less, when the solid content in the curable resin composition is 100% by mass, from the viewpoint of the strength of the cured product. , more preferably 45% by mass or less, particularly preferably 40% by mass or less. Further, since a cured product with a lower dielectric loss tangent can be obtained, the lower limit is preferably 5% by mass or more, and more preferably 10% by mass or more.

Furthermore, the ratio of (A) total amount of epoxy groups in the epoxy resin/(B) total amount of active ester groups in the compound having active ester groups in the curable resin composition of the present invention is preferably 0.2 or more and 0.2 or more. 6 or less, more preferably 0.2 or more and 0.5 or less, and even more preferably 0.3 or more and 0.5 or less. The ratio of (A) total amount of epoxy groups in the epoxy resin/(B) total amount of active ester groups in the compound having active ester groups in the curable resin composition of the present invention is 0.2 or more and 0.6 or less. Accordingly, a cured product having a high glass transition temperature (Tg) and a low dielectric loss tangent can be obtained while maintaining adhesion to the conductor.
In general, compounds with active ester groups are known to have lower adhesion to conductors than phenolic curing agents, so as shown in the above ratio, curable resin compositions have more active ester groups than epoxy groups. It was predicted that the adhesion to conductors would deteriorate in the case of products. However, in the present invention, even with a curable resin composition having the above ratio in which there are more active ester groups, it is possible to obtain a cured product that has high adhesion to conductors, high heat resistance, and low dielectric loss tangent. .

The total amount of epoxy groups in the epoxy resin (A) can be determined by dividing the amount of the epoxy resin (A) contained in the curable resin composition by the epoxy equivalent of the epoxy resin (A). The total amount of active ester groups of the compound having an active ester group (B) is the amount of the compound having an active ester group (B) contained in the curable resin composition. It can be determined by dividing by the active ester equivalent of . Note that (A) the epoxy resin and (B) the compound having an active ester group may each contain multiple types of compounds, but in that case, the amount of each compound is determined by the epoxy equivalent or the active Divide by the ester equivalent to determine the total amount of epoxy groups or the total amount of ester groups.

(B) Among the compounds having an active ester group, the following compounds (B1) and (B2) having an active ester group can be suitably used.

(B1)
(B1) The compound having an active ester group includes (b1) a phenol resin having a molecular structure in which phenols are linked via an aliphatic cyclic hydrocarbon group, (b2) an aromatic dicarboxylic acid or its halide, and (b3) It has a structure obtained by reacting an aromatic monohydroxy compound. The phenolic hydroxyl group in the phenolic resin (b1) is 0.05 to 0.75 mol per 1 mol of the carboxyl group or acid halide group in the aromatic dicarboxylic acid or its halide (b2), and the phenolic hydroxyl group in the phenolic resin (b3) is 0.05 to 0.75 mol. It is preferable to have a structure obtained by reacting an aromatic monohydroxy compound in a proportion of 0.25 to 0.95 mol.

Here, in (b1) phenol resin, the molecular structure in which phenols are linked via aliphatic cyclic hydrocarbon groups is an unsaturated aliphatic cyclic hydrocarbon compound containing two double bonds in one molecule. Examples include structures obtained by polyaddition reaction with phenols. Examples of the phenols include phenol and substituted phenols substituted with one or more alkyl groups, alkenyl groups, allyl groups, aryl groups, aralkyl groups, halogen groups, or the like. Specifically, examples include cresol, xylenol, ethylphenol, isopropylphenol, butylphenol, octylphenol, nonylphenol, vinylphenol, isopropenylphenol, allylphenol, phenylphenol, benzylphenol, chlorophenol, bromophenol, naphthol, dihydroxynaphthalene, etc. However, it is not limited to these. Also, a mixture of these may be used. Among these, phenol is particularly preferred because of its excellent fluidity and curability.

Specific examples of unsaturated alicyclic hydrocarbon compounds include dicyclopentadiene, tetrahydroindene, 4-vinylcyclohexene, 5-vinylnorbon-2-ene, α-pinene, β-pinene, and limonene. Can be mentioned. Among these, dicyclopentadiene is preferred from the viewpoint of property balance, particularly heat resistance and hygroscopicity. In addition, since dicyclopentadiene is contained in petroleum fractions, industrial dicyclopentadiene may contain other aliphatic or aromatic dienes as impurities, but it has good heat resistance, hardenability, Considering moldability and the like, it is desirable that the product has dicyclopentadiene purity of 90% by mass or more.

Next, the aromatic dicarboxylic acid or its halide (b2) is an aromatic dicarboxylic acid such as isophthalic acid, terephthalic acid, 1,4-, 2,3-, or 2,6-naphthalene dicarboxylic acid, and Examples include acid halides such as acid fluorides, acid chlorides, acid bromides, and acid iodides. Among these, acid chlorides of aromatic dicarboxylic acids are preferred because of their particularly good reactivity, and among these, isophthalic acid dichloride and terephthalic acid dichloride are preferred, with isophthalic acid dichloride being particularly preferred.

Next, aromatic monohydroxy compounds include, for example, phenol; alkylphenols such as o-cresol, m-cresol, p-cresol, and 3,5-xylenol; o-phenylphenol, p-phenylphenol, 2-benzyl Examples include aralkylphenols such as phenol, 4-benzylphenol, and 4-(α-cumyl)phenol; and naphthols such as α-naphthol and β-naphthol. Among these, α-naphthol and β-naphthol are particularly preferred since the dielectric loss tangent of the cured product is low.

（式中、Ｘ_１はベンゼン環またはナフタレン環を有する基であり、ｋは０または１を表し、ｎは繰り返し単位の平均値で０．０５～２．５である。）
で表される構造のものがとりわけ硬化物の誘電正接が低く、かつ、有機溶剤に溶解させた際の溶液粘度が低くなる点から好ましい。前記ベンゼン環またはナフタレン環を有する基は、特に限定されず、フェニル基、ナフチル基等でもよく、また、他の原子を介してベンゼン環またはナフタレン環が分子末端に結合していてもよく、置換基を有していてもよい。また、（Ｂ１）活性エステル基を有する化合物は、その分子末端にナフタレン環を有するものであることが好ましい。 (B1) A compound having an active ester group has a structure obtained by reacting (b1) a phenol resin, (b2) an aromatic dicarboxylic acid or its halide, and (b3) an aromatic monohydroxy compound. However, in particular, the following general formula (1)

(In the formula, X ₁ is a group having a benzene ring or a naphthalene ring, k represents 0 or 1, and n is an average value of repeating units of 0.05 to 2.5.)
Those having the structure represented by the above are particularly preferred because the dielectric loss tangent of the cured product is low and the solution viscosity when dissolved in an organic solvent is low. The group having a benzene ring or naphthalene ring is not particularly limited, and may be a phenyl group, a naphthyl group, etc., or the benzene ring or naphthalene ring may be bonded to the molecular terminal via another atom, and the group may be substituted. It may have a group. Further, (B1) the compound having an active ester group preferably has a naphthalene ring at the end of its molecule.

In particular, those in which the value of n in the above general formula (1), that is, the average value of repeating units, is in the range of 0.25 to 1.5 have low solution viscosity and are easy to manufacture into dry films for build-up. It is preferable from this point of view. Further, in the above general formula (1), the value of k is preferably 0 from the viewpoint of high heat resistance and low dielectric loss tangent.

Here, n in the above general formula (1) can be determined as follows.

[How to find n in general formula (1)]
Styrene equivalent molecular weights (α1, α2, α3, α4) corresponding to n = 1, n = 2, n = 3, n = 4, respectively, and n = 1, n = according to GPC measurements performed under the following conditions. 2, find the ratios (β1/α1, β2/α2, β3/α3, β4/α4) with the theoretical molecular weights (β1, β2, β3, β4) of n=3 and n=4, and calculate these (β1/α1). Find the average value of α1 to β4/α4). The average molecular weight is determined by multiplying the number average molecular weight (Mn) determined by GPC by this average value. Next, the value of n is calculated using the molecular weight of the general formula (1) as the average molecular weight.

(GPC measurement conditions)
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation,
Column: Tosoh guard column “HXL-L”
+ “TSK-GEL G2000HXL” manufactured by Tosoh Corporation
+ “TSK-GEL G2000HXL” manufactured by Tosoh Corporation
+ “TSK-GEL G3000HXL” manufactured by Tosoh Corporation
+ “TSK-GEL G4000HXL” manufactured by Tosoh Corporation
Detector: RI (differential refractive diameter)
Data processing: Tosoh Corporation “GPC-8020 Model II version 4.10”
Measurement conditions: Column temperature 40℃
Developing solvent: Tetrahydrofuran Flow rate: 1.0 ml/min Standard: The following monodisperse polystyrene with a known molecular weight was used in accordance with the measurement manual of the above-mentioned "GPC-8020 Model II Version 4.10".

(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
“A-1000” manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
“A-5000” manufactured by Tosoh Corporation
"F-1" manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
"F-4" manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
Tosoh Corporation "F-20"
“F-40” manufactured by Tosoh Corporation
"F-80" manufactured by Tosoh Corporation
Tosoh Corporation "F-128"
Sample: A 1.0% by mass tetrahydrofuran solution in terms of resin solid content was filtered through a microfilter (50 μl).

Specifically, the method of reacting (b1) a phenol resin, (b2) an aromatic dicarboxylic acid or its halide, and (b3) an aromatic monohydroxy compound involves reacting each of these components in the presence of an alkali catalyst. can be done.

Examples of alkali catalysts that can be used here include sodium hydroxide, potassium hydroxide, triethylamine, and pyridine. Among these, sodium hydroxide and potassium hydroxide are particularly preferred because they can be used in the form of an aqueous solution and have good productivity.

Specifically, in the reaction, (b1) a phenol resin, (b2) an aromatic dicarboxylic acid or its halide, and (b3) an aromatic monohydroxy compound are mixed in the presence of an organic solvent, and the alkali catalyst or its halide is mixed. A method of reacting while dropping an aqueous solution continuously or intermittently may be mentioned. At that time, the concentration of the aqueous solution of the alkali catalyst is preferably in the range of 3.0 to 30%. Furthermore, examples of organic solvents that can be used here include toluene and dichloromethane.

After the reaction is completed, if an aqueous solution of an alkaline catalyst is used, the reaction solution is separated by standing, the aqueous layer is removed, and the remaining organic layer is washed repeatedly until the aqueous layer becomes almost neutral. The desired resin can be obtained.

The active ester group-containing compound (B1) obtained in this way is usually obtained as a solution in an organic solvent, so when it is used as a varnish for laminates or a dry film for build-up, it can be used as is with other ingredients. The desired curable resin composition can be produced by mixing with the organic solvent and adjusting the amount of the organic solvent as appropriate. The compound (B1) having an active ester group is characterized by a low melt viscosity when dissolved in an organic solvent to form a resin solution. When a compound having an ester group is used, the solution viscosity is 300 to 10,000 mPa·s (25°C).

で表される構造部位を有し且つその両末端が一価のアリールオキシ基である構造を有するものである。 (B2)
The compound having an active ester group (B2) has the following general formula (2):

It has a structure represented by the following and has a structure in which both ends thereof are monovalent aryloxy groups.

で表される基または下記式（４）：

で表される基であり、ｍは１～６の整数であり、ｎはそれぞれ独立的に１～５の整数であり、ｑはそれぞれ独立的に０～６の整数であり、式（３）中、ｋはそれぞれ独立的に１～５の整数であり、式（４）中、Ｙは上記式（３）で表される基（ｋはそれぞれ独立的に１～５の整数）であり、ｔはそれぞれ独立的に０～５の整数である） (In formula (2), each X ₂ is independently represented by the following formula (3):

A group represented by or the following formula (4):

m is an integer of 1 to 6, n is each independently an integer of 1 to 5, q is each independently an integer of 0 to 6, and formula (3) where k is each independently an integer of 1 to 5, and in formula (4), Y is a group represented by the above formula (3) (k is each independently an integer of 1 to 5), (t is each independently an integer from 0 to 5)

で表される部分構造が、水酸基当量が１７０～２００グラム／当量の変性ナフタレン化合物の由来構造であることが好ましい。 The compound (B2) having an active ester group is represented by the general formula (2) above.

The partial structure represented by is preferably a structure derived from a modified naphthalene compound having a hydroxyl equivalent of 170 to 200 grams/equivalent.

In order to clarify the relationship between m and n in formula (2), some patterns are illustrated below, but the compound having an active ester group (B2) is not limited to these.

For example, when m=1, formula (2) represents the structure of formula (2-I) below.

In formula (2-I), n is an integer of 1 to 5, and q is each independently an integer of 0 to 6. Note that, similarly to the relationship between m and n, when n is 2 or more, each q is independently an integer from 0 to 6.

Further, for example, when m=2, formula (2) represents the structure of formula (2-II) below.

In formula (2-II), n is each independently an integer of 1 to 5, and q is each independently an integer of 0 to 6. Note that, similarly to the relationship between m and n, when n is 2 or more, each q is independently an integer from 0 to 6.

Since the compound having an active ester group (B2) has a naphthylene ether structural part in the main molecule skeleton, it can impart superior heat resistance and flame retardance to the cured product, and the structural part has the following formula ( Since the cured product has a structure bonded at the structural sites represented by 5), it is possible to provide a cured product with excellent dielectric properties. In addition, by having an aryloxy group as a structure at both ends in the structure of the compound having an active ester group (B2), the heat decomposition resistance of the cured product can be sufficiently improved even in multilayer printed circuit board applications. can get.

The active ester group-containing compound (B2) is preferably one having a softening point in the range of 100 to 200°C, particularly 100 to 190°C, in view of the excellent heat resistance of the cured product.

Among the compounds having an active ester group (B2), m in formula (2) may be an integer of 1 to 6. Among these, those in which m is an integer of 1 to 5 are preferred. In addition, n in formula (2) is each independently an integer of 1 to 5. Among these, those in which n is an integer of 1 to 3 are preferred.

To describe the relationship between m and n in formula (2), for example, if m is an integer of 2 or more, n of 2 or more will occur, but in that case, each n is an independent value. be. As long as n is within the numerical range, the values may be the same or different.

In the compound (B2) having an active ester group, when q is 1 or more in formula (2), X ₂ may be substituted at any position in the naphthalene ring structure.

The aryloxy groups at both ends of the structure include those derived from monohydric phenolic compounds such as phenol, cresol, pt-butylphenol (para-tert-butylphenol), 1-naphthol, and 2-naphthol. Among these, from the viewpoint of heat decomposition resistance of the cured product, phenoxy group, tolyloxy group or 1-naphthyloxy group are preferred, and 1-naphthyloxy group is more preferred.

Hereinafter, the method for producing the compound having an active ester group (B2) will be described in detail.

The method for producing a compound having an active ester group (B2) includes a step of reacting a dihydroxynaphthalene compound and benzyl alcohol in the presence of an acid catalyst to obtain a benzyl-modified naphthalene compound (hereinafter, this step is referred to as "Step 1"). ), then a step of reacting the obtained benzyl-modified naphthalene compound with an aromatic dicarboxylic acid chloride and a monohydric phenol compound (hereinafter, this step may be abbreviated as "Step 2"). ).

That is, first, in step 1, the dihydroxynaphthalene compound and benzyl alcohol are reacted in the presence of an acid catalyst to form a compound that has a naphthylene structure as a main skeleton, has phenolic hydroxyl groups at both ends, and has a naphthylene structure as its main skeleton. A benzyl-modified naphthalene compound having a structure in which a benzyl group is bonded pendantly to an aromatic nucleus can be obtained. It should be noted here that in general, when a dihydroxynaphthalene compound is converted into naphthylene ether under an acid catalyst, it is extremely difficult to control the molecular weight and the resulting product has a high molecular weight. By using these together, it is possible to suppress such an increase in molecular weight and obtain a resin suitable for electronic material applications.

Furthermore, by adjusting the amount of benzyl alcohol used, in addition to being able to adjust the content of benzyl groups in the target benzyl-modified naphthalene compound, it is also possible to adjust the melt viscosity of the benzyl-modified naphthalene compound itself. Become. That is, the reaction ratio of the dihydroxynaphthalene compound and benzyl alcohol is usually such that the reaction ratio of the dihydroxynaphthalene compound and benzyl alcohol (dihydroxynaphthalene compound)/(benzyl alcohol) is 1/0.1 to 1 on a molar basis. /10, but from the balance of heat resistance, flame retardance, dielectric properties, and heat decomposition resistance, the reaction ratio of the dihydroxynaphthalene compound and benzyl alcohol (dihydroxynaphthalene compound) on a molar basis /(benzyl alcohol) is preferably in the range of 1/0.5 to 1/4.0.

Dihydroxynaphthalene compounds that can be used here include, for example, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, -dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene and the like. Among these, 1,6-dihydroxynaphthalene is preferred because the resulting cured product of the benzyl-modified naphthalene compound has better flame retardancy, and the cured product also has a lower dielectric loss tangent and better dielectric properties. Alternatively, 2,7-dihydroxynaphthalene is preferred, and 2,7-dihydroxynaphthalene is more preferred.

Acid catalysts that can be used in the reaction between the dihydroxynaphthalene compound and benzyl alcohol in Step 1 include, for example, inorganic acids such as phosphoric acid, sulfuric acid, and hydrochloric acid, oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, and fluoromethane. Examples include organic acids such as sulfonic acid, Friedel-Crafts catalysts such as aluminum chloride, zinc chloride, stannic chloride, ferric chloride, and diethyl sulfate.

Further, the amount of the acid catalyst to be used can be appropriately selected depending on the target modification rate, etc., but for example, in the case of an inorganic acid or an organic acid, 0.001 to 5. 0 parts by weight, preferably 0.01 to 3.0 parts by weight, and in the case of Friedel-Crafts catalysts, 0.2 to 3.0 mol, preferably 0.5 to 3.0 mol, per mol of the dihydroxynaphthalene compound. The amount is preferably within a range of 2.0 mol.

The reaction between the dihydroxynaphthalene compound and benzyl alcohol in Step 1 can be carried out without a solvent, or in a solvent in order to improve the uniformity of the reaction system. Examples of such solvents include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and ethylene glycol monopropyl ether. , diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether; nonpolar aromatic solvents such as benzene, toluene, xylene; nonpolar aromatic solvents such as dimethylformamide and dimethyl sulfoxide; Protic polar solvents include chlorobenzene and the like.

A specific method for carrying out the reaction in step 1 is to dissolve the dihydroxynaphthalene compound, benzyl alcohol, and the acid catalyst in the absence of a solvent or in the presence of the solvent, and then heat the reaction at a temperature of about 60 to 180°C, preferably about 80 to 160°C. It can be carried out under temperature conditions. Further, the reaction time is not particularly limited, but is preferably 1 to 10 hours. Therefore, the reaction can be specifically carried out by maintaining the temperature for 1 to 10 hours. Further, it is preferable to distill off water generated during the reaction outside the system using a fractionating tube or the like, since the reaction proceeds quickly and productivity is improved.

Furthermore, if the obtained benzyl-modified naphthalene compound is highly colored, an antioxidant or a reducing agent may be added to the reaction system in order to suppress it. Examples of the antioxidant include hindered phenol compounds such as 2,6-dialkylphenol derivatives, divalent sulfur compounds, and phosphite ester compounds containing a trivalent phosphorus atom. Examples of the reducing agent include hypophosphorous acid, phosphorous acid, thiosulfuric acid, sulfurous acid, hydrosulfite, or salts thereof.

After the reaction is completed, the acid catalyst is removed by neutralization, washing with water, or decomposition, and the desired resin having a phenolic hydroxyl group can be separated by common operations such as extraction and distillation. Neutralization treatment and water washing treatment may be carried out according to conventional methods, and for example, basic substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia, triethylenetetramine, and aniline can be used as the neutralizing agent.

Here, specific examples of the aromatic dicarboxylic acid chloride include phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. Examples include acid chlorides. Among these, isophthalic acid chloride and terephthalic acid chloride are preferred from the viewpoint of the balance between solvent solubility and heat resistance.

Specific examples of the monohydric phenol compound include phenol, cresol, pt-butylphenol, 1-naphthol, and 2-naphthol. Among them, phenol, cresol, and 1-naphthol are preferred from the viewpoint of good reactivity with carboxylic acid chloride, and 1-naphthol is more preferred from the viewpoint of good heat decomposition resistance.

Here, in the method of reacting the benzyl-modified naphthalene compound, the aromatic dicarboxylic acid chloride, and further the monohydric phenol compound, specifically, each of these components can be reacted in the presence of an alkali catalyst.

Examples of alkali catalysts that can be used here include sodium hydroxide, potassium hydroxide, triethylamine, and pyridine. Among these, sodium hydroxide and potassium hydroxide are particularly preferred because they can be used in the form of an aqueous solution and have good productivity.

Specifically, the reaction can be carried out by mixing the above-mentioned components in the presence of an organic solvent, and allowing the reaction to occur while continuously or intermittently dropping the alkali catalyst or its aqueous solution. At this time, the concentration of the aqueous solution of the alkali catalyst is preferably in the range of 3.0 to 30% by mass. Furthermore, examples of organic solvents that can be used here include toluene, dichloromethane, and chloroform.

After the reaction is completed, if an aqueous solution of an alkaline catalyst is used, the reaction solution is separated by standing, the aqueous layer is removed, and the remaining organic layer is washed repeatedly until the aqueous layer becomes almost neutral. The desired resin can be obtained.

It is preferable that the compound (B2) having an active ester group obtained in this way has a softening point of 100 to 200° C., since the solubility in organic solvents will be high.

The curable resin composition of the present invention may contain a curing agent other than (B) a compound having an active ester group, as long as the effects of the present invention are not impaired. For example, a compound having a phenolic hydroxyl group, a polyester Examples include carboxylic acids and their acid anhydrides, compounds having a cyanate ester group, compounds having a maleimide group, and alicyclic olefin polymers.

[(C) Aminotriazine skeleton-containing additive]
The curable resin composition of the present invention contains (C) an aminotriazine skeleton-containing additive. (C) The aminotriazine skeleton-containing additive is added in order to maintain high heat resistance and low dielectric loss tangent of the cured product of the curable resin composition of the present invention, and to improve adhesion to the plated conductor.

Conventionally, it has been known to blend triazine skeleton-containing compounds such as triazine-containing phenolic resins into compositions containing epoxy resins and compounds having active ester groups, but this has been known to improve adhesion to plated conductors and lower dielectric loss tangent. In this respect, it was insufficient. In particular, it has been difficult to obtain adhesion to plated conductors when the amount of compounds having active ester groups or inorganic fillers is large, but in the curable resin composition of the present invention, (C) aminotriazine By blending a compound with a melting point as a skeleton-containing additive, it is possible to obtain a cured product that has high heat resistance, low dielectric loss tangent, and high adhesion to conductors. Although the mechanism for improving adhesion is not clear, the adhesion of the cured product to the plated conductor is brought about by the reaction of the amino group with epoxy and the coordination bond of nitrogen in the amino group and/or triazine ring with the conductor metal. it is conceivable that. In addition, by blending a compound with a melting point as an aminotriazine skeleton-containing additive, the curable resin composition before curing maintains adhesion to the plated conductor, compared to conventional aminotriazine skeleton-containing compounds that do not have a melting point. Since the fluidity and storage stability of the composition can be improved, a composition with high industrial utility value can be obtained.

(C) Examples of the aminotriazine skeleton-containing additive include those having a monoaminotriazinyl group, a diaminotriazinyl group, and a triaminotriazinyl group, and the hydrogen atoms of these amino groups are substituted. It may be something that is currently in use.

Specifically, for example, 2-amino-4-methoxy-6-(trifluoromethyl)-1,3,5-triazine, 2-(dibutylamino)-1,3,5-triazine-4,6- Dithiol, 6-diallylamino-1,3,5-triazine-2,4-dithiol, 6-(4-vinylbenzyl-n-propyl)amino-1,3,5-triazine-2,4-dithiol, 6 -(diisopropylamino)-1,3,5-triazine-2,4-dithiol, 6-(diisobutylamino)-1,3,5-triazine-2,4-dithiol, 6-di(2-ethylhexyl)amino -1,3,5-triazine-2,4-dithiol, 6-(allylamino)-1,3,5-triazine-2,4-dithiol, 6-(butylamino)-1,3,5-triazine- Examples include 2,4-dithiol.

（式（６）中、Ｒ^１はそれぞれ独立して水素原子または炭素数１～１２のアルキル基を表し、好ましくはＲ^１は水素原子又は炭素数１～４のアルキル基を表し、特に好ましくはＲ^１は水素原子を表す。）で表されるジアミノトリアジニル基であることが好ましい。 Among these, the aminotriazine skeleton of the (C) aminotriazine skeleton-containing additive is, for example, represented by the following formula (6).

(In formula (6), R ¹ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, preferably R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, particularly preferably A diaminotriazinyl group represented by R ¹ represents a hydrogen atom is preferred.

（式（７）中、Ｒ^２は水素原子又は炭素数１～４のアルキル基、好ましくはメチル基であり、Ｒ^３はそれぞれ独立して水素原子又は炭素数１～４のアルキル基、好ましくは炭素数１～２のアルキル基であり、ｐは０～３の整数、好ましくは０～１の整数、特に好ましくは０を表す。）で表される加水分解性シリル基又はシラノール基を有することが好ましい。 Furthermore, it is preferable that the (C) aminotriazine skeleton-containing additive has a hydroxyl group, and in particular, the (C) aminotriazine skeleton-containing additive has the following formula (7).

(In formula (7), R ² is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a methyl group, and R ³ is each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably It is an alkyl group having 1 to 2 carbon atoms, and p is an integer of 0 to 3, preferably an integer of 0 to 1, and particularly preferably 0.) Has a hydrolyzable silyl group or silanol group. is preferred.

Here, the hydrolyzable silyl group is an atomic group in which a hydrolyzable group is directly bonded to a silicon atom, and the hydrolyzable group refers to a group that can form a hydroxyl group under the influence of water. In formula (7), when p is any integer from 0 to 2 and R ³ is any alkyl group having 1 to 4 carbon atoms, the atom represented by formula (7) The group becomes a hydrolyzable silyl group, and the group represented by -OR ³ becomes a hydrolyzable group.

(C) Since the aminotriazine skeleton-containing additive has a hydrolyzable silyl group or silanol group of formula (7), if necessary, the silanol group generated by hydrolysis and the surface of the epoxy group of the epoxy resin or the inorganic filler The reaction occurs, and the silanol groups undergo dehydration condensation, and the (C) aminotriazine skeleton-containing additive is incorporated into the cured product.

In this way, the hydrolyzable silyl group or silanol group contributes to the incorporation of the (C) aminotriazine skeleton-containing additive into the cured product, resulting in many amino groups forming coordination bonds with the conductive metal. It is considered that the adhesion of the cured product of the curable resin composition of the present invention to the plated conductor is further improved.

From the viewpoint of increasing the stability of the silanol group after hydrolysis, the aminotriazine skeleton-containing additive (C) preferably has a hydrolyzable silyl group or silanol group in which p in formula (7) is 1.

On the other hand, from the viewpoint of increasing reactivity and crosslinking density, the aminotriazine skeleton-containing additive (C) preferably has a hydrolyzable silyl group or silanol group in which p in formula (7) is 0.

Among the (C) aminotriazine skeleton-containing additives having a diaminotriazinyl group of formula (6), examples of additives having a hydroxyl group include (4,6-diamino-[1,3,5]triazine-2 -ylamino)-methanol, 2-(4,6-diamino-[1,3,5]triazin-2-ylamino)-ethanol, 3-(4,6-diamino-[1,3,5]triazine-2 -ylamino)-propanol, 4-(4,6-diamino-[1,3,5]triazin-2-ylamino)-butanol, 5-(4,6-diamino-[1,3,5]triazine-2 -ylamino)-pentanol, 6-(4,6-diamino-[1,3,5]triazin-2-ylamino)-hexanol, 8-(4,6-diamino-[1,3,5]triazine- 2-ylamino)-octanol, 10-(4,6-diamino-[1,3,5]triazin-2-ylamino)-decanol, 12-(4,6-diamino-[1,3,5]triazine- 2-ylamino)-dodecanol, (4,6-bis-methylamino-[1,3,5]triazin-2-ylamino)-methanol, 2-(4,6-bis-methylamino-[1,3, 5] Triazin-2-ylamino)-ethanol, 3-(4,6-bis-methylamino-[1,3,5]triazin-2-ylamino)-propanol, 4-(4,6-bis-methylamino) -[1,3,5]triazin-2-ylamino)-butanol, 6-(4,6-bis-methylamino-[1,3,5]triazin-2-ylamino)-hexanol, 8-(4, 6-bis-methylamino-[1,3,5]triazin-2-ylamino)-octanol, 10-(4,6-bis-methylamino-[1,3,5]triazin-2-ylamino)-decanol , 12-(4,6-bis-methylamino-[1,3,5]triazin-2-ylamino)-dodecanol, (4,6-bis-ethylamino-[1,3,5]triazin-2- ylamino)-methanol, 2-(4,6-bis-ethylamino-[1,3,5]triazin-2-ylamino)-ethanol, 3-(4,6-bis-ethylamino-[1,3, 5] Triazin-2-ylamino)-propanol, 4-(4,6-bis-ethylamino-[1,3,5]triazin-2-ylamino)-butanol, 6-(4,6-bis-ethylamino) -[1,3,5]triazin-2-ylamino)-hexanol, 8-(4,6-bis-ethylamino-[1,3,5]triazin-2-ylamino)-octanol, 10-(4, 6-bis-ethylamino-[1,3,5]triazin-2-ylamino)-decanol, 12-(4,6-bis-ethylamino-[1,3,5]triazin-2-ylamino)-dodecanol , (4,6-bis-butylamino-[1,3,5]triazin-2-ylamino)-methanol, 2-(4,6-bis-butylamino-[1,3,5]triazin-2- ylamino)-ethanol, 3-(4,6-bis-butylamino-[1,3,5]triazin-2-ylamino)-propanol, 4-(4,6-bis-butylamino-[1,3, 5] Triazin-2-ylamino)-butanol, 6-(4,6-bis-butylamino-[1,3,5]triazin-2-ylamino)-hexanol, 8-(4,6-bis-butylamino) -[1,3,5]triazin-2-ylamino)-octanol, 10-(4,6-bis-butylamino-[1,3,5]triazin-2-ylamino)-decanol, 12-(4, 6-bis-butylamino-[1,3,5]triazin-2-ylamino)-dodecanol, (4,6-bis-dimethylamino-[1,3,5]triazin-2-ylamino)-methanol, 2 -(4,6-bis-dimethylamino-[1,3,5]triazin-2-ylamino)-ethanol, 3-(4,6-bis-dimethylamino-[1,3,5]triazin-2- ylamino)-propanol, 4-(4,6-bis-dimethylamino-[1,3,5]triazin-2-ylamino)-butanol, 6-(4,6-bis-dimethylamino-[1,3, 5] Triazin-2-ylamino)-hexanol, 8-(4,6-bis-dimethylamino-[1,3,5]triazin-2-ylamino)-octanol, 10-(4,6-bis-dimethylamino) -[1,3,5]triazin-2-ylamino)-decanol, 12-(4,6-bis-dimethylamino-[1,3,5]triazin-2-ylamino)-dodecanol, (4,6- Bis-diethylamino-[1,3,5]triazin-2-ylamino)-methanol, 2-(4,6-bis-diethylamino-[1,3,5]triazin-2-ylamino)-ethanol, 3-( 4,6-bis-diethylamino-[1,3,5]triazin-2-ylamino)-propanol, 4-(4,6-bis-diethylamino-[1,3,5]triazin-2-ylamino)-butanol , 6-(4,6-bis-diethylamino-[1,3,5]triazin-2-ylamino)-hexanol, 8-(4,6-bis-diethylamino-[1,3,5]triazin-2- ylamino)-octanol, 10-(4,6-bis-diethylamino-[1,3,5]triazin-2-ylamino)-decanol, 12-(4,6-bis-diethylamino-[1,3,5] triazin-2-ylamino)-dodecanol, (4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino)-methanol, 2-(4,6-bis-dibutylamino-[1, 3,5]triazin-2-ylamino)-ethanol, 3-(4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino)-propanol, 4-(4,6-bis- Dibutylamino-[1,3,5]triazin-2-ylamino)-butanol, 6-(4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino)-hexanol, 8-( 4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino)-octanol, 10-(4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino) -decanol, 12-(4,6-bis-dibutylamino-[1,3,5]triazin-2-ylamino)-dodecanol, and the like.

Examples of the aminotriazine skeleton-containing additive (C) having a hydrolyzable silyl group or silanol group of formula (7) include N-trihydroxysilanylmethyl-[1,3,5]triazine-2,4, 6-triamine, N-(2-trihydroxysilanyl-ethyl)-[1,3,5]triazine-2,4,6-triamine, N-(3-trihydroxysilanyl-propyl)-[1, 3,5]triazine-2,4,6-triamine, N-(4-trihydroxysilanyl-butyl)-[1,3,5]triazine-2,4,6-triamine, N-(6-triazine-2,4,6-triamine) hydroxysilanyl-hexyl)-[1,3,5]triazine-2,4,6-triamine, N-(8-trihydroxysilanyl-octyl)-[1,3,5]triazine-2,4, 6-triamine, N-(10-trihydroxysilanyl-decyl)-[1,3,5]triazine-2,4,6-triamine, N-(12-trihydroxysilanyl-dodecyl)-[1, 3,5]triazine-2,4,6-triamine, N-trimethoxysilanylmethyl-[1,3,5]triazine-2,4,6-triamine, N-(2-trimethoxysilanyl-ethyl )-[1,3,5]triazine-2,4,6-triamine, N-(3-trimethoxysilanyl-propyl)-[1,3,5]triazine-2,4,6-triamine, N -(4-trimethoxysilanyl-butyl)-[1,3,5]triazine-2,4,6-triamine, N-(6-trimethoxysilanyl-hexyl)-[1,3,5]triazine -2,4,6-triamine, N-(8-trimethoxysilanyl-octyl)-[1,3,5]triazine-2,4,6-triamine, N-(10-trimethoxysilanyl-decyl )-[1,3,5]triazine-2,4,6-triamine, N-(12-trimethoxysilanyl-dodecyl)-[1,3,5]triazine-2,4,6-triamine, N -triethoxysilanylmethyl-[1,3,5]triazine-2,4,6-triamine, N-(2-triethoxysilanyl-ethyl)-[1,3,5]triazine-2,4, 6-triamine, N-(3-triethoxysilanyl-propyl)-[1,3,5]triazine-2,4,6-triamine, N-(4-triethoxysilanyl-butyl)-[1, 3,5]triazine-2,4,6-triamine, N-(6-triethoxysilanyl-hexyl)-[1,3,5]triazine-2,4,6-triamine, N-(8-triazine-2,4,6-triamine) ethoxysilanyl-octyl)-[1,3,5]triazine-2,4,6-triamine, N-(10-triethoxysilanyl-decyl)-[1,3,5]triazine-2,4, 6-triamine, N-(12-triethoxysilanyl-dodecyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N''-trihydroxysilanylmethyl- [1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N”-(2-trihydroxysilanyl-ethyl)-[1,3,5]triazine-2,4 ,6-triamine, N,N'-dimethyl-N''-(3-trihydroxysilanyl-propyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl- N"-(4-trihydroxysilanyl-butyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-(6-trihydroxysilanyl-hexyl )-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N''-(8-trihydroxysilanyl-octyl)-[1,3,5]triazine-2 ,4,6-triamine, N,N'-dimethyl-N''-(10-trihydroxysilanyl-decyl)-[1,3,5]triazine-2,4,6-triamine, N,N'- Dimethyl-N"-(12-trihydroxysilanyl-dodecyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-trimethoxysilanylmethyl-[ 1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-(2-trimethoxysilanyl-ethyl)-[1,3,5]triazine-2,4, 6-triamine, N,N'-dimethyl-N''-(3-trimethoxysilanyl-propyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N "-(4-trimethoxysilanyl-butyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-(6-trimethoxysilanyl-hexyl) -[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N''-(8-trimethoxysilanyl-octyl)-[1,3,5]triazine-2, 4,6-triamine, N,N'-dimethyl-N''-(10-trimethoxysilanyl-decyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl -N"-(12-trimethoxysilanyl-dodecyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-triethoxysilanylmethyl-[1 ,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N"-(2-triethoxysilanyl-ethyl)-[1,3,5]triazine-2,4,6 -triamine, N,N'-dimethyl-N"-(3-triethoxysilanyl-propyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N" -(4-triethoxysilanyl-butyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N''-(6-triethoxysilanyl-hexyl)- [1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl-N”-(8-triethoxysilanyl-octyl)-[1,3,5]triazine-2,4 ,6-triamine, N,N'-dimethyl-N''-(10-triethoxysilanyl-decyl)-[1,3,5]triazine-2,4,6-triamine, N,N'-dimethyl- Examples include N''-(12-triethoxysilanyl-dodecyl)-[1,3,5]triazine-2,4,6-triamine.

These (C) aminotriazine skeleton-containing additives can be synthesized by known methods. Among the (C) aminotriazine skeleton-containing additives having a diaminotriazinyl group of formula (6), for those having a hydroxyl group, the method described in International Publication No. 2013/005021 pamphlet can be referred to. can. The (C) aminotriazine skeleton-containing additive having a hydrolyzable silyl group or silanol group of formula (7) is described in US Pat. No. 2,949,434 or Chemistry-A European Journal, Vol. 15, pp. 6279-6288. This method can be used as a reference.

Among the above-mentioned (C) aminotriazine skeleton-containing additives, the (C) aminotriazine skeleton-containing additive used in the present invention is preferred from the viewpoint of dispersibility in the curable resin composition. It is preferable to use a substance that can become liquid when mixed at a temperature and has a melting point. Specifically, the aminotriazine skeleton-containing additive (C) having a melting point of 180°C or lower, particularly preferably 70°C or higher and 160°C or lower, is used. In addition, in the present invention, the melting point shall be measured according to JIS K6220.

Furthermore, from the viewpoint of dispersibility in the curable resin composition, (C) the aminotriazine skeleton-containing additive is methyl ethyl ketone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate. It is preferable that the solubility in an organic solvent selected from mixtures of at least two or more of these is 5 g/100 g of organic solvent or more at 20°C. The method for measuring the solubility is shown below.

<Solubility measurement method>
In a 200 mL sample bottle, 100 g of the above organic solvent, a predetermined amount of the (C) aminotriazine skeleton-containing additive, and a stirrer were placed and stirred at 20°C for 10 minutes, then left at 20°C for 10 minutes, and dissolved by visual inspection. Observe and judge.

As described later, these organic solvents can be used to adjust the viscosity of the curable resin composition of the present invention. (C) the aminotriazine skeleton-containing additive is homogeneously present in the resin composition. As a result, it is thought that a cured product having high heat resistance, low dielectric loss tangent, and high adhesion to conductors can be obtained.

Furthermore, since the curable resin composition of the present invention contains (A) an epoxy resin for thermosetting, it is clear that the (C) aminotriazine skeleton-containing additive is soluble in the epoxy resin. It is preferable from the viewpoint of dispersibility in the resin composition. Specifically, the solubility of the aminotriazine skeleton-containing additive (C) in an epoxy resin having an epoxy equivalent of 500 or less is preferably 5 phr or more at 110°C. Here, solubility of 5 phr at 110°C means that when 5 g of (C) aminotriazine skeleton-containing additive is added to 100 g of epoxy resin with an epoxy equivalent of 500 or less, (C) aminotriazine skeleton-containing additive dissolves. It means there is nothing left. The method for measuring the solubility is shown below.

<Solubility measurement method>
Put 100 g of the epoxy resin, 5 g of the aminotriazine skeleton-containing additive, and a stirrer into a 200 mL sample bottle, stir at 110°C for 10 minutes, then leave to stand at 110°C for 10 minutes, and visually check to see if there is any undissolved residue. Observe and judge.

Examples of epoxy resins with an epoxy equivalent of 500 or less include NC-3000H (manufactured by Nippon Kayaku Co., Ltd.), YX-4000H, 828 (manufactured by Mitsubishi Chemical Corporation), and EXA-835LV (manufactured by DIC Corporation), It is not limited to this.

(C) Commercially available aminotriazine skeleton-containing additives include 2,4-diamino-6-vinyl-s-triazine (VT), a compound having a diaminotriazinyl group and a hydroxyl group of formula (6); (VD-3, VD-4), a compound (VD-5) having a diaminotriazinyl group of formula (6) and a hydrolyzable silyl group of formula (7) (manufactured by Shikoku Kasei Kogyo Co., Ltd.) Can be mentioned.

These (C) aminotriazine skeleton-containing additives may be used alone or in combination of two or more.

Furthermore, the mass ratio of (C) the aminotriazine skeleton-containing additive to the total amount of (A) the epoxy resin and (B) the compound having an active ester group is 0.001 or more and 0.100 or less in terms of solid content. It is preferably 0.001 or more and 0.05 or less, and even more preferably 0.005 or more and 0.03 or less.

(C) The mass ratio of the aminotriazine skeleton-containing additive to the total amount of (A) the epoxy resin and (B) the compound having an active ester group is 0.001 or more and 0.100 or less in terms of solid content. , high adhesion to conductors can be imparted while maintaining high heat resistance and low dielectric loss tangent of the cured product.

[(D) Inorganic filler]
The curable resin composition of the present invention contains (D) an inorganic filler. By incorporating an inorganic filler, the curing shrinkage of the resulting cured product is suppressed, resulting in a lower CTE (coefficient of thermal expansion) that matches the adhesion, hardness, and thermal strength of the conductive layer such as copper surrounding the insulating layer. As a result, thermal properties such as crack resistance can be improved. As the inorganic filler, conventionally known inorganic fillers can be used, and examples include silica such as barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, and spherical silica, talc, and clay. , Neuburg silica particles, boehmite, magnesium carbonate, calcium carbonate, titanium oxide, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, calcium zirconate, and other extender pigments, as well as copper, tin, zinc, nickel, silver, and palladium. , aluminum, iron, cobalt, gold, platinum, and other metal powders. Preferably, the inorganic filler is a spherical particle. Among these, silica is preferred because it suppresses curing shrinkage of the cured product of the curable resin composition, provides a lower CTE, and can improve properties such as adhesion and hardness. The average particle diameter (median diameter, D50) of the inorganic filler is preferably 0.01 to 10 μm, and the inorganic filler is preferably silica with a diameter of 0.01 to 3 μm. Note that in this specification, the average particle size of the inorganic filler includes not only the particle size of primary particles but also the particle size of secondary particles (agglomerates). The average particle size can be determined using a laser diffraction particle size distribution measuring device. Examples of a measuring device using a laser diffraction method include Microtrac MT3000II manufactured by Microtrac Bell Co., Ltd.

(D) The inorganic filler is preferably a surface-treated inorganic filler. As the surface treatment, surface treatment with a coupling agent or surface treatment without introducing an organic group such as alumina treatment may be performed. The surface treatment method for the inorganic filler is not particularly limited, and any known and commonly used method may be used. do it.

(D) The surface treatment of the inorganic filler is preferably surface treatment using a coupling agent. As the coupling agent, silane-based, titanate-based, aluminate-based, and zircoaluminate-based coupling agents can be used. Among these, silane coupling agents are preferred. Examples of such silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, N-(2-aminomethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-amino Propyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxy Examples include cyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane, which may be used alone or in combination. can be used. These silane coupling agents are preferably immobilized on the surface of the inorganic filler in advance by adsorption or reaction. Here, the amount of the coupling agent to be treated with respect to 100 parts by mass of the inorganic filler is, for example, 0.1 to 10 parts by mass.

As the curable reactive group, a thermosetting reactive group is preferred. Examples of thermosetting reactive groups include hydroxyl group, carboxyl group, isocyanate group, amino group, imino group, epoxy group, oxetanyl group, mercapto group, methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, oxazoline group, etc. can be mentioned. Among these, at least one of an amino group and an epoxy group is preferred. Note that the surface-treated inorganic filler may have a photocurable reactive group in addition to the thermosetting reactive group.

The surface-treated inorganic filler may be contained in the resin layer in a surface-treated state, and the inorganic filler and the surface treatment agent may be separately added to the curable resin composition forming the resin layer. Although the inorganic filler may be surface-treated in the composition by blending, it is preferable to blend the inorganic filler that has been surface-treated in advance. By blending an inorganic filler that has been surface-treated in advance, it is possible to prevent a decrease in crack resistance and the like due to the surface treatment agent that would remain if it were blended separately and was not consumed in the surface treatment. When surface-treated in advance, it is preferable to blend a pre-dispersion liquid in which an inorganic filler is pre-dispersed in a solvent or a curable resin. Alternatively, it is more preferable that the surface-untreated inorganic filler is sufficiently surface-treated when it is pre-dispersed in a solvent, and then the pre-dispersion is blended into the composition.

(D) The inorganic filler may be blended with an epoxy resin etc. in a powder or solid state, or may be blended with an epoxy resin etc. after being mixed with a solvent or a dispersant to form a slurry.

(D) The inorganic filler may be used alone or as a mixture of two or more. When the solid content in the curable resin composition is 100% by mass, the blending amount of the inorganic filler is preferably 50% by mass or more, more preferably 60% by mass or more, and 65% by mass or more from the viewpoint of lowering the CTE. is even more preferable. Further, from the viewpoint of the toughness of the cured film, the content is preferably 90% by mass or less, more preferably 80% by mass or less, and particularly preferably 75% by mass or less.

[Thermoplastic resin]
The curable resin composition of the present invention may further contain a thermoplastic resin in order to improve the mechanical strength of the resulting cured film. Preferably, the thermoplastic resin is soluble in a solvent. When it is soluble in a solvent, flexibility improves when it is formed into a dry film, and cracking and powder falling can be suppressed. As the thermoplastic resin, thermoplastic polyhydroxypolyether resin, phenoxy resin which is a condensation product of epichlorohydrin and various bifunctional phenol compounds, or various acid anhydrides and acid chlorides are used to replace the hydroxyl group of the hydroxyether moiety present in the skeleton. and esterified phenoxy resins, polyvinyl acetal resins, polyamide resins, polyamideimide resins, block copolymers, and the like. Thermoplastic resins can be used alone or in combination of two or more. Among these thermoplastic resins, phenoxy resin is preferred because it can improve the glass transition temperature while maintaining a low dielectric loss tangent. From the viewpoint of reducing the roughness of the surface of the cured product after desmearing, polyvinyl acetal resin is preferred.

The polyvinyl acetal resin can be obtained, for example, by acetalizing a polyvinyl alcohol resin with an aldehyde. The aldehyde is not particularly limited and includes, for example, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, amylaldehyde, hexylaldehyde, heptylaldehyde, 2-ethylhexylaldehyde, cyclohexylaldehyde, furfural, benzaldehyde, 2-methylbenzaldehyde, 3- Examples include methylbenzaldehyde, 4-methylbenzaldehyde, p-hydroxybenzaldehyde, m-hydroxybenzaldehyde, phenylacetaldehyde, and β-phenylpropionaldehyde, with butyraldehyde being preferred.

Specific examples of the phenoxy resin include FX280 and FX293 manufactured by Toto Kasei Co., Ltd., and YX8100, YX6954, YL6954, YL6974, and YX7200 manufactured by Mitsubishi Chemical Corporation. Specific examples of polyvinyl acetal resin include the S-LEC KS series manufactured by Sekisui Chemical Co., Ltd.; examples of polyamide resin include the KS5000 series manufactured by Hitachi Chemical Co., Ltd. and the BP series manufactured by Nippon Kayaku Co., Ltd., and polyamide-imide resins. Examples include the KS9000 series manufactured by Hitachi Chemical Co., Ltd. When blending the thermoplastic resin, the blending amount is determined based on the amount of the cured film obtained, assuming that the total of (A) epoxy resin and (B) compound having an active ester group in the curable resin composition is 100% by mass. From the viewpoint of mechanical strength, the content is preferably 0.1% by mass or more, more preferably 0.3% by mass or more. Further, from the viewpoint of the dielectric properties of the cured film, the content is preferably 20% by mass or less, more preferably 15% by mass or less.

[Curing accelerator]
The curable resin composition of the present invention can contain a curing accelerator. A curing accelerator accelerates a thermosetting reaction, and is used to further improve properties such as adhesion, chemical resistance, and heat resistance. Specific examples of such curing accelerators include imidazole and derivatives thereof; guanamines such as acetoguanamine and benzoguanamine; diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, Polyamines such as melamine and polybasic hydrazide; organic acid salts and/or epoxy adducts thereof; amine complexes of boron trifluoride; trimethylamine, triethanolamine, N,N-dimethyloctylamine, N-benzyldimethylamine, pyridine , dimethylaminopyridine, N-methylmorpholine, hexa(N-methyl)melamine, 2,4,6-tris(dimethylaminophenol), tetramethylguanidine, m-aminophenol, and other amines; polyvinylphenol, polyvinylphenol bromine polyphenols such as compounds, phenol novolacs, and alkylphenol novolacs; organic phosphines such as tributylphosphine, triphenylphosphine, and tris-2-cyanoethylphosphine; tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide, hexadecyltributyl Phosphonium salts such as phosphonium chloride; Quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; The above polybasic acid anhydrides; diphenyliodonium tetrafluoroboroate, triphenylsulfonium hexafluoroantimonate, 2,4,6 -Cationic photopolymerization catalysts such as triphenylthiopyrylium hexafluorophosphate; styrene-maleic anhydride resins; equimolar reaction products of phenyl isocyanate and dimethylamine, and organic polyisocyanates such as tolylene diisocyanate and isophorone diisocyanate and dimethylamine. Conventionally known curing accelerators such as equimolar reactants and metal catalysts can be used. Among the curing accelerators, imidazole, its derivatives, and dimethylaminopyridine are preferred, and dimethylaminopyridine is more preferred because it provides a cured product with higher Tg and lower dielectric loss tangent.

The curing accelerator can be used alone or in combination of two or more. The amount of the curing accelerator is determined based on the storage stability of the resin composition before the thermosetting reaction, assuming that the total solid content of (A) the epoxy resin and (B) the compound having an active ester group is 100% by mass. From the viewpoint, the content is preferably 5% by mass or less, more preferably 3% by mass or less, and from the viewpoint of curability, the content is preferably 0.01% by mass or more, and more preferably 0.1% by mass or more.

[Rubber-like particles]
The curable resin composition of the present invention can contain rubber particles as necessary. Such rubber particles include polybutadiene rubber, polyisopropylene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl-modified polybutadiene rubber, acrylonitrile-butadiene rubber modified with a carboxyl group or a hydroxyl group, and These include crosslinked rubber particles, core-shell type rubber particles, etc., and one type can be used alone or two or more types can be used in combination. These rubber-like particles are added to improve the flexibility of the resulting cured film, improve crack resistance, enable surface roughening treatment with oxidizing agents, and improve adhesion strength with copper foil, etc. be done.

The average particle diameter of the rubber particles is preferably in the range of 0.005 to 1 μm, more preferably in the range of 0.2 to 1 μm. The average particle diameter of the rubbery particles in the present invention can be determined using a laser diffraction particle size distribution measuring device. For example, rubber particles are uniformly dispersed in a suitable organic solvent using ultrasonic waves, etc., the particle size distribution of the rubber particles is created on a mass basis using Microtrac Bell's Nanotrac wave, and the median diameter is calculated as the average diameter. It can be measured by determining the particle size.

[Flame retardants]
The curable resin composition of the present invention can contain a flame retardant. Flame retardants include hydrated metals such as aluminum hydroxide and magnesium hydroxide, red phosphorus, ammonium phosphate, ammonium carbonate, zinc borate, zinc stannate, molybdenum compounds, bromine compounds, chlorine compounds, and phosphate esters. , phosphorus-containing polyol, phosphorus-containing amine, melamine cyanurate, melamine compound, triazine compound, guanidine compound, silicone polymer, etc. can be used. The flame retardants can be used alone or in combination of two or more.

[Organic solvent]
The curable resin composition of the present invention may contain an organic solvent for its preparation, viscosity adjustment for coating on a circuit board or support, formation of a resin layer of a dry film, and the like. The organic solvent is not particularly limited, but examples include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, etc. can. More specifically, ketones such as methyl ethyl ketone, cyclohexanone, methyl butyl ketone, and methyl isobutyl ketone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, and methyl carbitol. , butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether, and other glycol ethers; Esters such as ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate; ethanol, propanol, 2- Alcohols such as methoxypropanol, n-butanol, isobutyl alcohol, isopentyl alcohol, ethylene glycol, propylene glycol; Aliphatic hydrocarbons such as octane and decane; Petroleum such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha In addition to system solvents, examples include N,N-dimethylformamide (DMF), tetrachloroethylene, and turpentine oil. In addition, Swasol 1000 and Swasol 1500 manufactured by Maruzen Petrochemical Co., Ltd., Solvent #100 and Solvent #150 manufactured by Sankyo Chemical Co., Ltd., Shell Sol A100 and Shell Sol A150 manufactured by Shell Chemicals Japan, Ipsol No. 100 and Ipsol No. 150 manufactured by Idemitsu Kosan, etc. Organic solvents may also be used. The organic solvents can be used alone or in combination of two or more.

When formed into a dry film, the amount of residual solvent in the resin layer is preferably 0.1 to 10.0% by mass. When the residual solvent is 10.0% by mass or less, bumping during thermosetting is suppressed and the surface flatness becomes better. Furthermore, it is possible to prevent the melt viscosity from decreasing too much and causing the resin to flow, resulting in good flatness. When the residual solvent content is 0.1% by mass or more, fluidity during lamination is good, and flatness and embeddability are better.

[Other ingredients]
The curable resin composition of the present invention may further contain organic fillers such as silicon powder, fluorine powder, and nylon powder, phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, Conventionally known coloring agents such as carbon black and naphthalene black; conventionally known thickeners such as asbestos, olben, bentone, and finely divided silica; antifoaming agents and/or leveling agents such as silicone-based, fluorine-based, and polymer-based agents; , thiazole-based, triazole-based, adhesion-imparting agents such as silane coupling agents, and conventionally known additives such as titanate-based and aluminum-based additives.

The thermosetting resin composition of the present invention may be used in the form of a dry film or in liquid form. When used in liquid form, it may be one-component or two-component or more, but preferably two-component or more from the viewpoint of storage stability.

<Dry film>
The dry film of the present invention can be manufactured by applying the curable resin composition of the present invention onto a carrier film and drying it to form a resin layer as a dry coating film. A protective film can be laminated on the resin layer, if necessary.

The carrier film has a role of supporting the resin layer of the dry film, and is a film to which a curable resin composition is applied when forming the resin layer. Examples of carrier films include polyester films such as polyethylene terephthalate and polyethylene naphthalate, films made of thermoplastic resins such as polyimide films, polyamideimide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, and polystyrene films; Surface-treated paper or the like can be used. Among these, polyester films can be preferably used from the viewpoints of heat resistance, mechanical strength, handleability, and the like. The thickness of the carrier film is not particularly limited, but is appropriately selected in the range of approximately 10 to 150 μm depending on the application. The surface of the carrier film on which the resin layer is provided may be subjected to a mold release treatment. Further, sputtering or copper foil may be formed on the surface of the carrier film on which the resin layer is provided.

The protective film is provided on the opposite side of the resin layer from the carrier film for the purpose of preventing dust etc. from adhering to the surface of the resin layer of the dry film and improving handling properties. As the protective film, for example, a film made of a thermoplastic resin as exemplified in the carrier film, surface-treated paper, etc. can be used, but among these, polyester film, polyethylene film, and polypropylene film are preferable. The thickness of the protective film is not particularly limited, but is appropriately selected in the range of approximately 10 to 150 μm depending on the application. The surface of the protective film on which the resin layer is provided may be subjected to a mold release treatment.

<Resin coated copper foil>
The resin-coated copper foil of the present invention has a resin layer obtained by applying the curable resin composition of the present invention to a copper foil surface of a copper foil or a carrier-coated copper foil and drying it.

[Copper foil with carrier]
The carrier-attached copper foil may have a structure including a carrier foil and a copper foil in this order, and the resin layer made of the curable resin composition of the present invention may be laminated so as to be in contact with the copper foil. It is preferable to use ultra-thin copper foil as the copper foil.

Examples of the carrier foil include copper foil, aluminum foil, stainless steel (SUS) foil, and a resin film whose surface is coated with metal, and copper foil is preferable. The copper foil may be an electrolytic copper foil or a rolled copper foil. The thickness of the carrier foil is usually 250 μm or less, preferably 9 to 200 μm. Note that a release layer may be formed between the carrier foil and the copper foil, if necessary.

The method of forming the copper foil is not particularly limited, but it is preferable to form an ultra-thin copper foil, and wet film forming methods such as electroless copper plating and electrolytic copper plating, dry film forming methods such as sputtering and chemical vapor deposition, and , can be formed by a combination of these. The thickness of the ultra-thin copper foil is preferably 0.1 to 7.0 μm, more preferably 0.5 to 5.0 μm, and even more preferably 1.0 to 3.0 μm.

<Cured product>
The cured product of the present invention is obtained by curing the curable resin composition of the present invention, the resin layer of the dry film of the present invention, or the resin layer of the resin-coated copper foil of the present invention.

The method of curing is not particularly limited, and any conventionally known method may be used, for example, by heating at 150 to 230°C. As a method for manufacturing a printed wiring board using a curable resin composition, for example, in the case of a dry film with a three-layer structure in which a resin layer is sandwiched between a carrier film and a protective film, printing is performed using the following method. Wiring boards can be manufactured. Either the carrier film or the protective film is peeled off from the dry film, heated and laminated onto a circuit board on which a circuit pattern has been formed, and then thermally cured. Thermal curing may be performed by curing in an oven or by using a hot plate press. When laminating or hot plate pressing a base material on which a circuit is formed and the dry film of the present invention, a copper foil or a base material on which a circuit is formed can also be laminated at the same time. A printed wiring board can be manufactured by forming a pattern or a via hole by laser irradiation or drilling at a position corresponding to a predetermined position on a substrate on which a circuit pattern is formed, and exposing the circuit wiring. At this time, if there is a component (smear) that has not been completely removed and remains on the circuit wiring in the pattern or via hole, a desmear process is performed. The remaining carrier film or protective film may be peeled off after lamination, after thermosetting, after laser processing, or after desmear processing.

In addition, when manufacturing a printed wiring board using the resin-coated copper foil of the present invention, the resin layer is laminated on a circuit board on which a circuit pattern is formed, and the copper foil is used as all or part of the wiring layer to form a modified semi-additive. The circuit may be formed using a process (MSAP) method to produce a build-up wiring board. Alternatively, a build-up wiring board may be manufactured in which the copper foil is removed and a circuit is formed using a semi-additive process (SAP) method. Alternatively, a printed wiring board may be manufactured by direct build-up on wafer, in which lamination of resin-coated copper foil and circuit formation are alternately repeated on a semiconductor integrated circuit. Alternatively, a coreless build-up method may be used in which resin layers and conductor layers are alternately laminated without using a core substrate.

<Electronic parts>
The electronic component of the present invention has a cured product of the present invention, that is, a cured product of the curable resin composition of the present invention, a resin layer of a dry film of the present invention, or a resin layer of a resin-coated copper foil of the present invention.

Examples of electronic components include permanent protective films for printed wiring boards, and among them, solder resist layers, interlayer insulation layers, and coverlays for flexible printed wiring boards. In addition, electronic components include applications other than printed wiring boards, such as passive components such as inductors.

In addition to the above-mentioned uses, the curable resin composition of the present invention can also be suitably used for permanently filling holes in printed wiring boards, for example, filling holes such as through holes and via holes. It can also be used as a sealing material for semiconductor chips, and as a material for copper clad laminates (CCL) and prepregs.

Further, since the cured product of the curable resin composition of the present invention has excellent dielectric properties, it can be suitably used for high frequency applications where transmission loss is an issue. Specific examples of high-frequency applications include substrates for millimeter-wave radar and millimeter-wave sensors for autonomous driving, mobile motherboards for high-speed communication, and SLP (Substrate-Like PCB) where circuits are formed using the modified semi-additive process (MSAP) method. ), application processors (AP) for mobile and personal computers, high multilayer substrates for base station servers and routers, substrates for antennas, and semiconductor encapsulation materials.

Furthermore, a wiring board may be formed by bonding wiring using the dry film of the present invention.

The form of the circuit forming material using the curable resin composition of the present invention is resin-coated copper foil (RCC) compatible with modified semi-additive process (MSAP) and resin-coated copper foil (RCC) compatible with semi-additive process (SAP). It may also be a build-up film.

Although the dielectric loss tangent of the cured product of the present invention is not particularly limited, according to the present invention, it is possible to obtain a cured product with a low dielectric loss tangent, for example, 0.003 or less, further 0.002 or less, or even It is also possible to set it to 0.001 or less.

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited only to these Examples. In addition, unless otherwise specified below, "parts" and "%" shall mean parts by mass and mass %.

((B) Synthesis of compound having active ester group)
[Synthesis example 1]
203.0 g of isophthalic acid chloride (number of moles of acid chloride group: 2.0 moles) and 1338 g of toluene were placed in a flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer, and the system was replaced with nitrogen under reduced pressure. and dissolved. Next, 96.0 g (0.67 mol) of α-naphthol and 220 g of dicyclopentadiene phenol resin (number of moles of phenolic hydroxyl group: 1.33 mol) were charged, and the system was replaced with nitrogen under reduced pressure to dissolve them. Thereafter, 1.12 g of tetrabutylammonium bromide was dissolved, and 400 g of a 20% aqueous sodium hydroxide solution was added dropwise over 3 hours while controlling the inside of the system to 60° C. or lower while purging with nitrogen gas. Stirring was then continued under these conditions for 1.0 hour. After the reaction was completed, the mixture was allowed to stand still for liquid separation, and the aqueous layer was removed. Furthermore, water was added to the toluene phase in which the reactants were dissolved, and the mixture was stirred and mixed for about 15 minutes, and the mixture was allowed to stand still for liquid separation to remove the aqueous layer. This operation was repeated until the pH of the aqueous layer reached 7. Thereafter, water was removed by dehydration using a decanter to obtain a compound (B-1) having an active ester group in a toluene solution state with a non-volatile content of 65%.

The ester group equivalent of the obtained compound (B-1) having an active ester group was 223 g/mol in terms of solid content.

[Synthesis example 2]
Into a flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer, 320 g (2.0 mol) of 2,7-dihydroxynaphthalene, 184 g (1.7 mol) of benzyl alcohol, and para-toluenesulfonic acid. 5.0 g of monohydrate was charged and stirred at room temperature while blowing nitrogen. Thereafter, the temperature was raised to 150° C., and the mixture was stirred for 4 hours while distilling the generated water out of the system. After the reaction was completed, 900 g of methyl isobutyl ketone and 5.4 g of 20% aqueous sodium hydroxide solution were added to neutralize, and then the aqueous layer was removed by liquid separation, washed three times with 280 g of water, and methyl isobutyl ketone was removed under reduced pressure. The residue was removed to obtain 460 g of a benzyl-modified naphthalene compound (B-2 intermediate). The obtained benzyl-modified naphthalene compound (B-2 intermediate) was a black solid, and the hydroxyl equivalent was 180 g/equivalent.

Next, 203.0 g of isophthalic acid chloride (number of moles of acid chloride group: 2.0 mol) and 1400 g of toluene were charged into another flask equipped with a thermometer, dropping funnel, cooling tube, fractionating tube, and stirrer. The inside of the system was replaced with nitrogen under reduced pressure to dissolve it. Next, 96.0 g (0.67 mol) of α-naphthol and 240 g (mol number of phenolic hydroxyl group: 1.33 mol) of a benzyl-modified naphthalene compound (B-2 intermediate) were charged, and the inside of the system was replaced with nitrogen under reduced pressure. Dissolved. Thereafter, 0.70 g of tetrabutylammonium bromide was dissolved, and 400 g of a 20% aqueous sodium hydroxide solution was added dropwise over 3 hours while controlling the inside of the system to 60° C. or lower while purging with nitrogen gas. Stirring was then continued under these conditions for 1.0 hour. After the reaction was completed, the mixture was allowed to stand still for liquid separation, and the aqueous layer was removed. Further, water was added to the toluene layer in which the reactants were dissolved, and the mixture was stirred and mixed for 15 minutes, and the mixture was allowed to stand still for liquid separation to remove the aqueous layer. This operation was repeated until the pH of the aqueous layer reached 7. Thereafter, water was removed by dehydration using a decanter to obtain a compound (B-2) having an active ester group in a toluene solution state with a nonvolatile content of 65% by mass. The resulting active ester group-containing compound (B-2) had an ester group equivalent of 230 g/mol in terms of solid content.

<1. Preparation of curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 5>
A curable resin composition for producing a cured film (cured film) was prepared by kneading and mixing together with various components shown in Examples and Comparative Examples shown in Table 1 below in the proportions (parts by mass) shown in Table 1. Note that the numerical values in the table indicate parts by mass (in terms of solid content).

For each of the curable resin compositions, test samples were prepared as shown below, and the glass transition temperature (Tg), dielectric loss tangent, and peel strength were evaluated. The results are shown in Table 1.

<Preparation of film after curing>
Using a film applicator, the curable resin composition was applied to the glossy surface of copper foil (F2-WS manufactured by Furukawa Electric Co., Ltd., 18 μm thick) for each of the Examples and Comparative Examples, and dried for 90 minutes in a hot air circulation drying oven. After drying at 10° C. for 10 minutes and subsequently curing at 200° C. for 60 minutes, the copper foil was peeled off to produce a cured film with a thickness of about 40 μm.

<Measurement of glass transition temperature (Tg)>
The sample obtained in the above <Preparation of film after curing> was cut into a measurement size (3 mm x 10 mm size), and the glass transition temperature (Tg) was measured using TMA Q400EM manufactured by TA Instruments. . The temperature was raised from room temperature at a heating rate of 10°C/min, and the measurement was carried out twice in succession, and the glass transition temperature (Tg), which is the intersection of two tangents with different linear thermal expansion coefficients, was evaluated using the following criteria in the second measurement. .

◎: 175℃ or more ○: Less than 175℃ 170℃ or more ×: Less than 170℃

<Measurement of dielectric loss tangent (Df)>
The sample obtained in the above <Preparation of film after curing> was cut into a measurement size (50 mm x 60 mm), and dielectric loss tangent of 10 GHz at 23°C was measured using an SPDR dielectric resonator and a network analyzer (both manufactured by Agilent). were measured and evaluated using the following criteria.

◎: Less than 0.003 ○: 0.003 or more and less than 0.005 ×: 0.005 or more

<Preparation of sample for peel strength measurement>
(1) Roughening treatment of the laminate Both sides of the glass cloth base epoxy resin double-sided copper-clad laminate [copper foil thickness 18 μm, board thickness 0.3 mm, Panasonic R5715ES] on which inner layer circuits were formed were coated by MEC Co., Ltd. The copper surface was subjected to roughening treatment (etching amount: approximately 1 μm) by immersing it in CZ8100 manufactured by Co., Ltd.

(2) Preparation of resin-coated copper foil Using a film applicator, apply the curable resin composition to a carrier-coated ultra-thin copper foil (MT18Ex manufactured by Mitsui Kinzoku Co., Ltd., ultra-thin copper 3 μm thick) for each example and comparative example. It was applied onto the surface of a thin copper foil and dried at 90° C. for 10 minutes in a hot air circulation drying oven to obtain a resin-coated copper foil with a resin layer thickness of about 40 μm.

(3) Lamination of resin-coated copper foil Using a batch vacuum pressure laminator MVLP-500 (manufactured by Meiki Seisakusho Co., Ltd., trade name), laminated resin-coated copper foil on both sides of the laminate that has been roughened (1). The resin composition coated surface of foil (2) was laminated. Lamination was carried out by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing for 30 seconds at 80° C. and a pressure of 0.5 MPa.

(4) Curing of resin composition The laminate (3) on which resin-coated copper foil was laminated was cured at 170° C. for 30 minutes in a hot air circulation drying oven.

(5) Electrolytic copper plating After curing, the carrier copper foil was peeled off from both sides of the laminate, and ultra-thin copper foil (3 μm) on both sides was made approximately 25 μm thick by electrolytic copper plating.

(6) Annealing The laminate after electrolytic copper plating was annealed at 200° C. for 60 minutes in a hot air circulation drying oven.

<Measurement of peel strength>
Using the sample prepared by the above method, it was measured according to JIS C6481 and evaluated according to the following criteria.

◎: 0.5kN/m or more ○: Less than 0.5kN/m 0.4kN/m or more ×: Less than 0.4kN/m

*1: Mixture product of bisphenol A type epoxy resin and bisphenol F type epoxy resin (liquid, epoxy equivalent: 165g/eq) (EXA-835LV: manufactured by DIC)
*2: Biphenyl novolac type epoxy resin (solid, epoxy equivalent: 290g/eq) (NC-3000H: manufactured by Nippon Kayaku Co., Ltd.)
*3: Triazine skeleton-containing phenol novolac resin (LA-7052: manufactured by DIC)
*4: Phenoxy resin (YX7200B35: manufactured by Mitsubishi Chemical Corporation)
*5: SO-C2 manufactured by Admatex treated with phenylaminosilane (spherical silica, average particle size: 0.5 μm, carbon content per unit mass 0.18)
*6: Compound having a diaminotriazinyl group and a hydroxyl group of formula (6) (melting point 151-154°C, solubility in propylene glycol monomethyl ether at 20°C less than 0.5% by mass, solubility in NC-3000H 110°C) less than 5 phr at °C) (VD-3: manufactured by Shikoku Kasei Kogyo Co., Ltd.)
*7: Compound having a diaminotriazinyl group of formula (6) and a hydrolyzable silyl group of formula (7) (melting point 80-90°C, solubility in propylene glycol monomethyl ether 50% by mass at 20°C, NC Solubility in -3000H is 5 phr or more at 110°C) (VD-5: manufactured by Shikoku Kasei Kogyo Co., Ltd.)
*8: Vinyltrimethoxysilane (KBM-1003: manufactured by Shin-Etsu Chemical Co., Ltd.)
*9: 3-glycidoxypropyltrimethoxysilane (KBM-403: manufactured by Shin-Etsu Chemical Co., Ltd.)
*10: N-phenyl-3-aminopropyltrimethoxysilane (KBM-573: manufactured by Shin-Etsu Chemical Co., Ltd.)
*11: Ratio of (A) total amount of epoxy groups in epoxy resin/(B) total amount of active ester groups in compounds having active ester groups in the curable resin composition
*12: Content rate (mass%) of (D) inorganic filler relative to the total mass (solid content equivalent) of the curable resin composition
*13: Mass ratio (in terms of solid content) of (C) aminotriazine skeleton-containing additive to the total amount of (A) epoxy resin and (B) compound having an active ester group in the curable resin composition. In comparative examples, the mass ratio (in terms of solid content) of the silane coupling agent to the total amount of (A) epoxy resin and (B) compound having an active ester group is described as the above mass ratio.)

The results shown in Table 1 show that the curable resin compositions of Examples can provide cured products that have high heat resistance, high adhesion, and low dielectric loss tangent.

Claims (8)

(A) an epoxy resin;
(B) a compound having an active ester group;
(C) an aminotriazine skeleton-containing additive;
(D) an inorganic filler;
A curable resin composition containing,
(C) the aminotriazine skeleton-containing additive has a melting point measured according to JIS K6220,
(A) The ratio of the total amount of epoxy groups in the epoxy resin/(B) the total amount of active ester groups in the compound having active ester groups is 0.2 or more and 0.6 or less,
(C) The mass ratio of the aminotriazine skeleton-containing additive to the total amount of (A) the epoxy resin and (B) the compound having an active ester group is 0.001 or more and 0.100 or less in terms of solid content,
(C) A curable resin composition characterized in that the aminotriazine skeleton-containing additive further has a hydrolyzable silyl group or silanol group . (C) The solubility of the aminotriazine skeleton-containing additive in an organic solvent selected from the group consisting of methyl ethyl ketone, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate is 5 g/100 g of organic solvent or more at 20°C. The curable resin composition according to claim 1, characterized by: The curable resin composition according to claim 1 or 2, wherein the solubility of the aminotriazine skeleton-containing additive (C) in an epoxy resin having an epoxy equivalent of 500 or less is 5 phr or more at 110°C. Any one of claims 1 to 3 , characterized in that (D) the inorganic filler is contained in a range of 50% by mass or more and 90% by mass or less, when the solid content in the curable resin composition is 100% by mass. The curable resin composition described in 1. A dry film comprising the curable resin composition according to any one of claims 1 to 4 as a resin layer. A resin-coated copper foil comprising the curable resin composition according to any one of claims 1 to 4 as a resin layer on the copper foil or the carrier-coated copper foil. A cured product of the curable resin composition according to any one of claims 1 to 4 , the resin layer of the dry film according to claim 5 , or the resin layer of the resin-coated copper foil according to claim 6 . An electronic component comprising the cured product according to claim 7 .