JP2020166212A - Curable resin composition, dry film, cured product, and printed wiring board - Google Patents

Abstract

To provide a curable resin composition which is excellent in improvement of adhesion between SR and EMC after plasma treatment, and has high reliability.SOLUTION: A curable resin composition contains (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin and (D) a surface-treated inorganic filler, in which (C) the epoxy resin contains (C1) an epoxy resin represented by formula (I) and (C2) a bisphenol A type, a bisphenol F type or a phenol novolac type epoxy resin having less than three functional groups.SELECTED DRAWING: None

Description

The present invention relates to a curable resin composition. Furthermore, the present invention relates to a dry film, a cured product, and a printed wiring board using the curable resin composition.

In recent years, due to the rapid progress of semiconductor components, electronic devices tend to be lighter, thinner, shorter, smaller, have higher performance, and have more functions. Following this tendency, miniaturization and multi-pinning of semiconductor packages have been put into practical use.

Specifically, BGA (ball grid array), CSP (chip scale package), etc., instead of IC packages called QFP (quad flat pack package), SOP (small outline package), etc. An IC package called is used. In recent years, FC-CSP (flip chip chip scale package) has also been put into practical use as an IC package with a higher density. The requirements for printed wiring boards (also called package substrates) used in such IC packages are diversifying, and various characteristics are also required for encapsulants, which are important materials that make up semiconductor packages, and they are diversifying. It was.

For example, a fine pitch wiring BGA package has a wide range of required characteristics, such as a sealant that requires low melt viscosity and low warpage, and a flip chip package that requires low stress and high adhesion reliability. .. The encapsulant, which is one of the materials constituting such a semiconductor package, is a thermosetting resin in which an epoxy resin and a filler are mainly combined, and is also called EMC (epoxy mold compound).

In the package assembly process, plasma treatment is performed before molding the EMC. This treatment not only cleans the surface to remove foreign substances adhering in various processes such as solder reflow and plating before sealing the EMC, but also makes the surface of SR (solder resist) uneven to form an EMC. It also has the meaning of improving the adhesion of the solder. Therefore, plasma treatment is an indispensable process that must be performed, and stable adhesion between EMC and SR after plasma treatment is important.

In addition to stable adhesion to various EMCs, which have been diversified in recent years, SR must be in stable adhesion to EMCs even in various package assembly processes under severe conditions. For example, in recent years, the solder used at the time of reflow is generally lead-free due to consideration for the environment, and requires a higher reflow temperature than before. Even in a high temperature environment in such a reflow process, SR and EMC must be in stable contact with each other. In this way, stable adhesion between SR and EMC is required, which can be applied to new package assembly processes in recent years.

Japanese Unexamined Patent Publication No. 2016-031987

However, in recent years, the composition described in Patent Document 1 has not been sufficiently good in adhesion between SR and EMC after plasma treatment.

Therefore, an object of the present invention is to provide a curable resin composition that is used for a printed wiring board or the like, has excellent adhesion between SR and EMC after plasma treatment, and is highly reliable. Another object of the present invention is a dry film having a resin layer composed of a dry coating film of the resin composition, a cured product of the resin composition or the resin layer of the dry film, and a printed wiring board having the cured product. Is to provide.

As a result of intensive research and development on a curable resin composition that is excellent in improving the adhesion between SR and EMC after plasma treatment and has high reliability, the present inventors have combined two specific types of epoxy resins. The present invention has been completed by finding that a cured product having excellent adhesion between SR and EMC after plasma treatment and having high reliability can be obtained by using a specific inorganic filler.

で表されるエポキシ樹脂と、
（Ｃ２）３官能未満の、ビスフェノールＡ型、ビスフェノールＦ型、またはフェノールノボラック型エポキシ樹脂と、を含むことを特徴とする。 That is, the curable resin composition according to the present invention contains (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a surface-treated inorganic filler. A curable resin composition
The (C) epoxy resin
(C1) The following formula (I):

Epoxy resin represented by
(C2) It is characterized by containing bisphenol A type, bisphenol F type, or phenol novolac type epoxy resin having less than trifunctionality.

In the aspect of the present invention, it is preferable that the curable resin composition further contains (E) an ultraviolet absorber.

In an aspect of the present invention, the surface-treated inorganic filler has at least one photoreactive group selected from the group consisting of an acryloyl group, a metaacryloyl group, a vinyl group, a cyclic ether group, and a cyclic thioether group on the surface. It is preferable to have.

A dry film according to another aspect of the present invention is characterized by comprising a support film and a resin layer composed of a dry coating film of the curable resin composition formed on the support film. ..

A cured product according to another aspect of the present invention is characterized in that it is obtained by curing the curable resin composition or the resin layer of the dry film.

A printed wiring board according to another aspect of the present invention is characterized by comprising the cured product.

An electronic component according to another aspect of the present invention is characterized by comprising the cured product.

According to the present invention, it is possible to provide a curable resin composition which is excellent in improving the adhesion between SR and EMC after plasma treatment and has high reliability. Further, according to the present invention, a dry film having a resin layer composed of a dry coating film of the resin composition, a cured product of the resin composition or the resin layer of the dry film, and a printed wiring board having the cured product. Can be provided.

[Curable resin composition]
The curable resin composition according to the present invention contains at least (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a surface-treated inorganic filler. .. In the curable resin composition, by using (C1) an epoxy resin having a specific structure and (C2) a specific epoxy resin having less than trifunctionality in combination, the adhesion between SR and EMC after plasma treatment can be improved. An excellent and highly reliable curable resin composition can be obtained. Hereinafter, each component constituting the curable resin composition according to the present invention will be described.

[(A) Carboxylic group-containing resin]
As the carboxyl group-containing resin (A), various conventionally known resins having a carboxyl group in the molecule can be used. When the curable resin composition contains a carboxyl group-containing resin, alkali developability can be imparted to the curable resin composition. In particular, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond in the molecule is preferable from the viewpoint of photocurability and development resistance. The ethylenically unsaturated double bond is preferably derived from acrylic acid or methacrylic acid or a derivative thereof. When only a carboxyl group-containing resin having no ethylenically unsaturated double bond is used, in order to make the composition photocurable, a compound having a plurality of ethylenically unsaturated groups in the molecule described later, that is, light It is necessary to use a polymerizable monomer together. Specific examples of the carboxyl group-containing resin include the following compounds (either oligomer or polymer).

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, or isobutylene.

(2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates, carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate-based polyols and polyether-based compounds. A carboxyl group-containing urethane resin obtained by a double addition reaction of a diol compound such as a polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic polyol, a bisphenol A-based alkylene oxide adduct diol, and a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(3) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Meta) A carboxyl group-containing photosensitive urethane resin obtained by a double addition reaction of an acrylate or a modified partial acid anhydride thereof, a carboxyl group-containing dialcohol compound and a diol compound.

(4) During the synthesis of the resin according to (2) or (3), a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added to the terminal (4). Meta) Acryloylated carboxyl group-containing photosensitive urethane resin.

(5) During the synthesis of the resin according to (2) or (3), one isocyanate group and one or more (meth) acryloyl groups are formed in the molecule, such as an isophorone diisocyanate and pentaerythritol triacrylate isomorphic reaction product. A carboxyl group-containing photosensitive urethane resin that is terminally (meth) acrylicized by adding a compound to it.

(6) A carboxyl group-containing photosensitive resin obtained by reacting a bifunctional or higher polyfunctional (solid) epoxy resin with (meth) acrylic acid and adding a dibasic acid anhydride to a hydroxyl group existing in a side chain.

(7) Carboxylic acid obtained by reacting (meth) acrylic acid with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of a bifunctional (solid) epoxy resin with epichlorohydrin, and adding a dibasic acid anhydride to the generated hydroxyl groups. Group-containing photosensitive resin.

(8) A dicarboxylic acid such as adipic acid, phthalic acid, or hexahydrophthalic acid is reacted with a bifunctional oxetane resin, and the generated primary hydroxyl group is subjected to two bases such as phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride. A carboxyl group-containing polyester resin to which an acid anhydride is added.

(9) An epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol, and (meth). Reacting with an unsaturated group-containing monocarboxylic acid such as acrylic acid, maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipine with respect to the alcoholic hydroxyl group of the obtained reaction product. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic anhydride such as an acid.

(10) Reaction obtained by reacting an unsaturated group-containing monocarboxylic acid with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(11) Reaction obtained by reacting a reaction organism obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate by reacting an unsaturated group-containing monocarboxylic acid. A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(12) A carboxyl group-containing photosensitive resin obtained by further adding a compound having one epoxy group and one or more (meth) acryloyl groups in one molecule to the resins (1) to (11).

In addition, in this specification, (meth) acrylate is a term which collectively refers to acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

The (A) carboxyl group-containing resin that can be used in the present invention is not limited to those listed above. Also. One type of the (A) carboxyl group-containing resin listed above may be used alone, or a plurality of types may be mixed and used. Among the above-listed, carboxyl group-containing resins synthesized by using compounds having phenolic hydroxyl groups such as carboxyl group-containing resins (10) and (11) as starting materials are excellent in HAST resistance and PCT resistance. Therefore, it can be preferably used.

In the present invention, the acid value of the (A) carboxyl group-containing resin is in the range of 30 to 150 mgKOH / g in consideration of the developability and the drawability of the resist pattern when a weak alkaline developer such as an aqueous sodium carbonate solution is used. Is preferable, and more preferably in the range of 50 to 120 mgKOH / g. (A) The higher the acid value of the carboxyl group-containing resin, the better the developability. However, since the exposed portion is dissolved by the developing solution, the exposed portion and the unexposed portion may be dissolved and peeled off by the developing solution. ..

The weight average molecular weight of the carboxyl group-containing resin (A) varies depending on the resin skeleton, but is generally in the range of 2,000 to 150,000, preferably in the range of 5,000 to 100,000. By using the (A) carboxyl group-containing resin having a weight average molecular weight of 2,000 or more, the resolution and tack-free performance can be improved. Further, the developability and storage stability can be improved by using the (A) carboxyl group-containing resin having a weight average molecular weight of 150,000 or less. The weight average molecular weight can be measured by gel permeation chromatography (GPC).

As the carboxyl group-containing resin (A), one type may be used alone, or two or more types may be used in combination. The blending amount of the carboxyl group-containing resin (A) is, for example, 5 to 30% by mass based on the total solid content of the composition.

[(B) Photopolymerization Initiator]
(B) Examples of the photopolymerization initiator include an acylphosphine oxide-based photopolymerization initiator, an oxime ester-based photopolymerization initiator having an oxime ester group, an α-aminoacetophenone-based photopolymerization initiator, and a titanosen-based photopolymerization initiator. Examples thereof include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. Among them, from the viewpoint of resolution of the curable resin composition, an acylphosphine oxide-based photopolymerization initiator is preferable.

Examples of the acylphosphine oxide-based photopolymerization initiator include bisacylphosphine oxide-based photopolymerization initiators and monoacylphosphine oxide-based photopolymerization initiators. Specifically, bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) ) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis- (2,6-) Dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6-trimethylbenzoyl)- Bisacylphosphine oxides such as phenylphosphine oxide; 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphinic acid methyl ester, Examples thereof include monoacylphosphine oxides such as 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

As the acylphosphine oxide-based photopolymerization initiator, a commercially available product may be used, and examples thereof include Omnirad TPO, Omnirad TPO-L, LR8953X, and Omnirad 819 manufactured by IGM Resins.

The blending amount of the (B) photopolymerization initiator is preferably 0.1 to 20 parts by mass, and 0.5 to 18 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin in terms of solid content. It is more preferably parts, and further preferably 1 to 15 parts by mass. By setting the blending amount of the photopolymerization initiator (B) within the above numerical range, the photocurability of the curable resin composition can be further improved. Further, it is possible to improve the chemical resistance and the like of the cured product formed by using the curable resin composition.

[(C) Epoxy resin]
By using the following two types of (C1) epoxy resin and (C2) epoxy resin in combination as the (C) epoxy resin, the adhesion between SR and EMC after plasma treatment is excellent and highly reliable. A curable resin composition can be obtained.

The epoxy resin (C1) is a trifunctional epoxy resin represented by the following formula (I).

Examples of the commercially available (C1) epoxy resin include Techmore VG3101L manufactured by Printec Co., Ltd.

The (C2) epoxy resin is a less than trifunctional epoxy resin, and is a bisphenol A type, a bisphenol F type, or a phenol novolac type epoxy resin. One of these epoxy resins may be used alone, or two or more of these epoxy resins may be used in combination.

Commercially available (C2) epoxy resins include jER 828 manufactured by Mitsubishi Chemical Corporation of bisphenol A type epoxy resin, EPICRON 840 manufactured by DIC Corporation, EPICRON 850 manufactured by DIC Corporation, and Mitsubishi Chemical Co., Ltd. manufactured by bisphenol F type epoxy resin. Examples thereof include jER 807, EPICRON 830 manufactured by DIC Corporation, EPICRON 835 manufactured by DIC Corporation, and DEN431 manufactured by Dow Chemical Corporation, which is a phenol novolac type epoxy resin. As these epoxy resins, those that are liquid at room temperature (20 ° C.) may be used alone, those that are solid at room temperature may be used alone, and two or more of liquid and solid may be used in combination. May be good. Of these, those that are liquid at room temperature (20 ° C.) are preferably used alone, and those that are used in combination with liquid and solid are preferable.

The compounding ratio (mass ratio) of the (C1) epoxy resin and the (C2) epoxy resin in the curable resin composition is preferably 1: 9 to 9: 1. When the blending ratio of the (C1) epoxy resin and the (C2) epoxy resin is within the above range, an excellent and highly reliable curable resin composition can be obtained by improving the adhesion between SR and EMC after plasma treatment. Can be done.

The blending amount of (C) epoxy resin (total blending amount of (C1) epoxy resin and (C2) epoxy resin) is 0.6 with respect to 1 equivalent of the carboxyl group of the (A) carboxyl group-containing resin. It is preferably ~ 2.5 equivalents.

[(D) Surface-treated inorganic filler]
(D) The surface-treated inorganic filler is characterized by having a photoreactive or heat-reactive functional group (reactive group) on the surface. By using such a filler, heat resistance and adhesion can be improved by reacting with a carboxyl group-containing resin or a thermosetting resin.

(D) The surface-treated inorganic filler can be obtained by treating the surface of the filler with a surface treatment agent having a reactive group, for example, a coupling agent having a reactive group as an organic group.

Examples of the inorganic filler include silica, hydrotalcite, talc, clay, barium sulfate, barium titanate, titanium oxide, aluminum oxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, Neuburg silica soil, glass powder, natural mica, and the like. Synthetic mica, iron oxide, mineral wool, aluminum silicate, calcium silicate and the like can be used. Of these, silica is preferred.

Examples of the photoreactive group include an acryloyl group, a metaacryloyl group, a vinyl group, a cyclic ether group, a cyclic thioether group and the like. Among these, at least one of a (meth) acryloyl group and a vinyl group is preferable.

Examples of the thermoreactive group include a hydroxyl group, a carboxyl group, an isocyanate group, an amino group, an imino group, an epoxy group, an oxetanyl group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group and an oxazoline group. Can be mentioned. Among these, at least one of an amino group and an epoxy group is preferable.

As the coupling agent, a coupling agent capable of introducing the above-mentioned photoreactive group or heat-reactive group into the filler can be used. As the coupling agent, for example, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, or the like can be used. Among these, a silane coupling agent is preferable. Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminomethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-aminopropyltri. Methoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) Ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane and the like can be mentioned, and these can be used alone or in combination. It is preferable that these silane coupling agents are previously immobilized on the surface of the filler by adsorption or reaction.

The surface-treated inorganic filler (D) may be contained in the curable resin composition of the present invention in a surface-treated state, and the surface-untreated inorganic filler and the surface treatment agent are separately blended. The inorganic filler may be surface-treated in the composition, but it is preferable to blend the inorganic filler which has been surface-treated in advance. In the case of surface treatment in advance, it is preferable to mix a pre-dispersion solution in which an inorganic filler is pre-dispersed in a solvent or a curable component. It is more preferable to add the pre-dispersion liquid to the composition after sufficient surface treatment when pre-dispersing the surface-untreated inorganic filler in the solvent.

The average particle size of the surface-treated inorganic filler (D) is preferably 5 μm or less, and more preferably 0.4 to 1.0 μm. Here, the average particle size is the average particle size of the inorganic filler alone or the inorganic filler dispersion liquid. Further, a nanofiller having a particle diameter of 100 nm or less of the primary particles can also be used in combination. Here, in the present specification, the average particle size of the inorganic filler is an average particle size (D50) including not only the particle size of the primary particles but also the particle size of the secondary particles (aggregates), and is a laser diffraction method. It is a value of D50 measured by. Examples of the measuring device by the laser diffraction method include the Microtrac MT3300EXII manufactured by Microtrac Bell. The average particle size of the inorganic filler contained in the curable resin composition in the present invention is a value measured as described above for the inorganic filler before adjusting (preliminary stirring, kneading) the curable resin composition. Let's say.

The blending amount of the surface-treated inorganic filler (D) is preferably 20% by mass or more and 80% by mass or less, more preferably 30% by mass or more and 70% by mass or less in terms of solid content, per the curable resin composition. Is. When the blending amount of the surface-treated inorganic filler (D) is 20% by mass or more and 80% by mass or less, heat resistance and adhesion can be further improved.

[(E) UV absorber]
(E) Any ultraviolet absorber can be used as long as it absorbs light having a wavelength of 300 nm to 450 nm. If the blending amount of the (D) surface-treated inorganic filler in the curable resin composition is high, the resolution may be lowered and it may be difficult to form an opening at the time of pattern formation. However, in the present invention, by further blending the (E) ultraviolet absorber with the curable resin composition, the occurrence of halation and undercut can be suppressed, and a stable and good opening can be formed.

Examples of the (E) ultraviolet absorber include an inorganic ultraviolet absorber and an organic ultraviolet absorber. (E) As the ultraviolet absorber, one type may be used alone, or two or more types may be used in combination.

Examples of the organic ultraviolet absorber include benzophenone derivatives, benzoate derivatives, benzotriazole derivatives, triazine derivatives, benzothiazole derivatives, synnamate derivatives, anthranilate derivatives, dibenzoylmethane derivatives and the like. Specific examples of the benzophenone derivative include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone and 2,4-dihydroxybenzophenone. Can be mentioned. Specific examples of benzoate derivatives include 2-ethylhexyl salicylate, phenyl salicylate, pt-butylphenyl salicylate, and 2,4-di-t-butylphenyl-3,5-di-t. Examples thereof include −butyl-4-hydroxybenzoate and hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate. Specific examples of the benzotriazole derivative include 2- (2'-hydroxy-5'-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2 -(2'-Hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-t-butylphenyl) -5 Examples thereof include -chlorobenzotriazole, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and 2- (2'-hydroxy-3', 5'-di-t-amylphenyl) benzotriazole. Specific examples of the triazine derivative include hydroxyphenyltriazine, bisethylhexyloxyphenol methoxyphenyl triazine and the like. Among these, it is preferable to use a triazine derivative.

The UV absorber may be commercially available, for example, TINUVIN PS, TINUVIN 99-2, TINUVIN 109, TINUVIN 384-2, TINUVIN 900, TINUVIN 928, TINUVIN 1130, TINUVIN 400, TINUVIN 405, TINUVIN 460, Examples include TINUVIN 479 (above, manufactured by BASF Japan Ltd., trade name).

The amount of the ultraviolet absorber (E) to be blended is preferably 0.01 to 10% by mass, more preferably 0.02 to 7 with respect to 100 parts by mass of the (A) carboxyl group-containing resin in terms of solid content. It is by mass, more preferably 0.05 to 5% by mass.

[Photopolymerizable monomer]
A photopolymerizable monomer can be blended in the curable resin composition of the present invention. The photopolymerizable monomer is a monomer having an ethylenically unsaturated double bond. Examples of such photopolymerizable monomers include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth). Hydroxyalkyl (meth) acrylates such as acrylates; Mono or di (meth) acrylates of alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol; hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane , Polyvalent alcohols such as dipentaerythritol, trishydroxyethyl isocyanurate, or polyvalent (meth) acrylates of these ethylene oxides or propylene oxide adducts; phenoxyethyl (meth) acrylates, polyethoxydi (meth) acrylates of bisphenol A, etc. (Meta) acrylates of ethylene oxide or propylene oxide adducts of phenols; (meth) acrylates of glycidyl ethers such as glycerin diglycidyl ether, trimethylpropan triglycidyl ether, triglycidyl isocyanurate; and melamine (meth). ) Acrylate can be mentioned. As the photopolymerizable monomer, one type may be used alone, or two or more types may be used in combination.

The blending amount of the photopolymerizable monomer is preferably 0.1 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin in terms of solid content. When the blending amount is 0.1 part by mass or more, the photocurability is good, and pattern formation is easy in alkaline development after irradiation with active energy rays. On the other hand, when the amount is 40 parts by mass or less, halation is unlikely to occur and good resolution can be obtained.

[Thermosetting component]
A thermosetting component can be blended in the curable resin composition of the present invention. It can be expected that the heat resistance of the composition will be improved by adding the thermosetting component. As the thermosetting component, one type may be used alone or two or more types may be used in combination. As the thermosetting component, any known one can be used. For example, known thermocurable components such as amino resins such as melamine resins, benzoguanamine resins, melamine derivatives and benzoguanamine derivatives, isocyanate compounds, blocked isocyanate compounds, cyclocarbonate compounds, oxetane compounds, episulfide resins and carbodiimide resins can be used. Particularly preferred is a thermocurable component having a plurality of cyclic ether groups or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in the molecule.

The thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is a compound having a plurality of 3, 4 or 5-membered cyclic (thio) ether groups in the molecule, and a plurality of oxetanols in the molecule. Examples thereof include a compound having a group, that is, a polyfunctional oxetane compound, a compound having a plurality of thioether groups in the molecule, that is, an episulfide resin and the like.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, and 1,4-bis [(3-3). Methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-3- Oxetane) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate and polyfunctional oxetane such as their oligomers or copolymers, as well as oxetane alcohol and novolak resin , Poly (p-hydroxystyrene), cardo-type bisphenols, calix arrayes, calix resorcinarenes, etherified compounds with a resin having a hydroxyl group such as silsesquioxane, and the like. In addition, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate can also be mentioned.

Examples of amino resins such as melamine derivatives and benzoguanamine derivatives include methylol melamine compounds, methylol benzoguanamine compounds, methylol glycol uryl compounds and methylol urea compounds.

As the isocyanate compound, a polyisocyanate compound can be blended. Examples of the polyisocyanate compound include 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, m-xylylene diisocyanate and Aromatic polyisocyanates such as 2,4-tolylene dimer; aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate) and isophorone diisocyanate; bicyclo Alicyclic polyisocyanates such as heptanthriisocyanate; and adducts, burettes, and isocyanurates of the isocyanate compounds mentioned above can be mentioned.

As the blocked isocyanate compound, an addition reaction product of the isocyanate compound and the isocyanate blocking agent can be used. Examples of the isocyanate compound capable of reacting with the isocyanate blocking agent include the above-mentioned polyisocyanate compound and the like. Examples of isocyanate blocking agents include phenol-based blocking agents; lactam-based blocking agents; active methylene-based blocking agents; alcohol-based blocking agents; oxime-based blocking agents; mercaptan-based blocking agents; acid amide-based blocking agents; imide-based blocking agents; Amine-based blocking agents; imidazole-based blocking agents; imine-based blocking agents and the like can be mentioned.

The amount of the thermosetting component blended is preferably 0.5 to 2.5 mol, more preferably 0., With respect to 1 mol of the carboxyl group contained in the (A) carboxyl group-containing resin. It is 8 to 2.0 mol.

[Thermosetting catalyst]
A thermosetting catalyst can be added to the curable resin composition of the present invention. Examples of the thermosetting catalyst include imidazole, 2-methylimidazole, 2-ethyl imidazole, 2-ethyl-4-methyl imidazole, 2-phenyl imidazole, 4-phenyl imidazole, 1-cyanoethyl-2-phenyl imidazole, 1-. Imidazole derivatives such as (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzyl Examples thereof include amine compounds such as amines, 4-methyl-N and N-dimethylbenzylamine, hydrazine compounds such as adipic acid dihydrazide and sebasic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Commercially available products include, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both are trade names of imidazole compounds) manufactured by Shikoku Kasei Kogyo Co., Ltd., and U-CAT manufactured by San Apro Co., Ltd. Examples thereof include 3513N (trade name of a dimethylamine compound), DBU, DBN, U-CAT SA 102 (all of which are bicyclic amidine compounds and salts thereof). In particular, the present invention is not limited to these, as long as it is a thermosetting catalyst of an epoxy resin or an oxetane compound, or one that promotes the reaction of at least one of an epoxy group and an oxetanel group with a carboxyl group, either alone or 2 You may use a mixture of seeds or more.

In addition, guanamine, acetguanamine, benzoguanamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S S-triazine derivatives such as -triazine / isocyanuric acid adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adduct can also be used, and preferably also functions as an adhesion imparting agent thereof. The compound to be used in combination with a thermosetting catalyst. One type of thermosetting catalyst may be used alone, or two or more types may be used in combination.

The blending amount of the thermosetting catalyst is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 0.5 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin in terms of solid content. It is a department. When it is 0.1 part by mass or more, it has excellent heat resistance. If it is 10 parts by mass or less, the storage stability is improved.

[Colorant]
A colorant can be added to the curable resin composition of the present invention. The colorant is not particularly limited, and known colorants such as red, blue, green, and yellow can be used, and any of pigments, dyes, and pigments may be used, but it may reduce the environmental load and affect the human body. It is preferable that the colorant does not contain halogen from the viewpoint of less.

Examples of red colorants include monoazo, disazo, azolake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, quinacridone, etc., and specifically, the following colors. -Index (CI; issued by The Society of Dyersand Colorists) numbered ones.

Examples of monoazo red colorants include Pigment Red 1,2,3,4,5,6,8,9,12,14,15,16,17,21,22,23,31,32,112,114, Examples thereof include 146, 147, 151, 170, 184, 187, 188, 193, 210, 245, 253, 258, 266, 267, 268, 269 and the like. Examples of the disazo-based red colorant include Pigment Red 37, 38, 41 and the like. Further, as a monoazolake-based red colorant, Pigment Red 48: 1,48: 2,48: 3,48: 4,49: 1,49: 2,50: 1,52: 1,52: 2,53: Examples thereof include 1,53: 2,57: 1,58: 4,63: 1,63: 2,64: 1,68. Examples of the benzimidazolone-based red colorant include Pigment Red 171, 175, 176, 185, 208 and the like. Examples of the perylene-based red colorant include Solvent Red 135,179, Pigment Red 123,149,166,178,179,190,194,224 and the like. Examples of the diketopyrrolopyrrole-based red colorant include Pigment Red 254, 255, 264, 270, 272 and the like. Examples of the condensed azo red colorant include Pigment Red 220, 144, 166, 214, 220, 211, 242 and the like. Examples of the anthraquinone-based red colorant include Pigment Red 168, 177, 216 and Solvent Red 149, 150, 52, 207. Examples of the quinacridone-based red colorant include Pigment Red 122, 202, 206, 207, and 209.

Examples of the blue colorant include phthalocyanine-based and anthraquinone-based compounds, and pigment-based compounds include compounds classified as Pigment. For example, Pigment Blue 15,15: 1,15: 2,15: 3,15: 4,15: 6,16,60. As the dye system, Solvent Blue 35, 63, 68, 70, 83, 87, 94, 97, 122, 136, 67, 70 and the like can be used. In addition to the above, metal-substituted or unsubstituted phthalocyanine compounds can also be used.

Examples of the yellow colorant include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, anthraquinone, and the like. For example, the anthraquinone yellow colorant includes Solvent Yellow 163, Pigment Yellow 24, 108, 193, 147, 199, 202 and the like can be mentioned. Examples of the isoindolinone-based yellow colorant include Pigment Yellow 110, 109, 139, 179, 185 and the like. Pigment Yellow as a condensed azo yellow colorant
93, 94, 95, 128, 155, 166, 180 and the like can be mentioned. Examples of the benzimidazolone-based yellow colorant include Pigment Yellow 120, 151, 154, 156, 175, 181 and the like. In addition, as a monoazo yellow colorant, Pigment Yellow 1,2,3,4,5,6,9,10,12,61,62,62:1,65,73,74,75,97,100, Examples thereof include 104, 105, 111, 116, 167, 168, 169, 182, 183 and the like. Examples of the disazo-based yellow colorant include Pigment Yellow 12, 13, 14, 16, 17, 55, 63, 81, 83, 87, 126, 127, 152, 170, 172, 174, 176, 188, 198 and the like. Can be mentioned.

In addition, colorants such as purple, orange, brown, black, and white may be added. Specifically, Pigment Black 1,6,7,8,9,10,11,12,13,18,20,25,26,28,29,30,31,32, Pigment Violet 19, 23, 29 , 32, 36, 38, 42, Solvent Violet 13, 36, C.I. I. Pigment Orange 1,5,13,14,16,17,24,34,36,38,40,43,46,49,51,61,63,64,71,73, PigmentBrown 23,25, Carbon Black, Examples include titanium oxide.

[Organic solvent]
The curable resin composition of the present invention may contain an organic solvent for the purpose of preparing the composition, adjusting the viscosity when applied to a substrate or a film, and the like. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethyl benzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol and propylene glycol monomethyl ether. , Dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether and other glycol ethers; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbi Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha are known. Conventional organic solvents can be used. One of these organic solvents may be used alone, or two or more of them may be used in combination.

[Other additive ingredients]
If necessary, the curable resin composition of the present invention further includes a photoinitiator, a cyanate compound, an elastomer, a mercapto compound, a urethanization catalyst, a thixotropic agent, an adhesion accelerator, a block copolymer, and a chain transfer agent. , Polymerization inhibitors, copper damage inhibitors, antioxidants, rust preventives, fine powder silica, organic bentonite, thickeners such as montmorillonite, silicone-based, fluorine-based, polymer-based defoaming agents and leveling agents at least. In any one of them, components such as silane coupling agents such as imidazole type, thiazole type and triazole type, and flame retardant agents such as phosphinate, phosphoric acid ester derivative, and phosphorus compound such as phosphazene compound can be blended. As these, those known in the field of electronic materials can be used.

The curable resin composition may be used as a dry film or as a liquid. When used as a liquid, it may be one-component or two-component or more.

[Use]
The curable resin composition according to the present invention is useful for forming a pattern layer as a permanent coating of a printed wiring board such as a solder resist, a coverlay, and an interlayer insulating layer, and is particularly useful for forming a solder resist. Further, since the curable resin composition of the present invention can form a cured product having excellent film strength even with a thin film, it is used in a printed wiring board that requires thinning, for example, a package substrate (printed wiring board used for a semiconductor package). It can also be suitably used for forming a pattern layer. Further, the cured product obtained from the curable resin composition of the present invention can be suitably used for forming a pattern layer on a package substrate having a thin total thickness and insufficient rigidity in terms of high elastic modulus and low CTE. It can be done.

Further, the curable resin composition according to the present invention can be used not only for forming a pattern layer of a cured film but also for an application not forming a pattern layer, for example, a molding application (sealing application).

[Dry film]
The curable resin composition of the present invention is in the form of a dry film including a support (carrier) film and a resin layer composed of a dry coating film of the curable resin composition formed on the support film. You can also. When forming a dry film, the curable resin composition of the present invention is diluted with the above organic solvent to adjust the viscosity to an appropriate level, and a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse coater, and a transfer coater are used. , A gravure coater, a spray coater or the like is applied onto a carrier film to a uniform thickness, and the film is usually dried at a temperature of 50 to 130 ° C. for 1 to 30 minutes to obtain a film. The coating film thickness is not particularly limited, but is generally selected as appropriate in the range of 1 to 150 μm, preferably 10 to 60 μm after drying.

As the support film, any known one can be used without particular limitation. For example, a polyester film such as polyethylene terephthalate or polyethylene naphthalate, a polyimide film, a polyamideimide film, a polypropylene film, a thermoplastic resin such as a polystyrene film or the like can be used. A film made of the above can be preferably used. Among these, a polyester film is preferable from the viewpoint of heat resistance, mechanical strength, handleability and the like. Further, a laminate of these films can also be used as a support film.

Further, the thermoplastic resin film as described above is preferably a film stretched in the uniaxial direction or the biaxial direction from the viewpoint of improving the mechanical strength.

The thickness of the support film is not particularly limited, but can be, for example, 10 μm to 150 μm.

After forming a resin layer made of a dry coating film of the curable resin composition of the present invention on a support film, it is further peeled off from the surface of the resin layer for the purpose of preventing dust from adhering to the surface of the resin layer. It is preferable to laminate a possible protective (cover) film. As the peelable protective film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper or the like can be used, and when the protective film is peeled off, the adhesive strength between the resin layer and the support film is increased. However, the adhesive strength between the resin layer and the protective film may be smaller.

The thickness of the protective film is not particularly limited, but can be, for example, 10 μm to 150 μm.

To form a cured film on a printed wiring board using a dry film, peel off the protective film from the dry film, overlay the exposed resin layer of the dry film on the circuit-formed base material, and attach it using a laminator or the like. Together, a resin layer is formed on the circuit-formed base material. Next, the formed resin layer is exposed, developed, and heat-cured to form a cured film. The protective film may be peeled off either before or after exposure.

[Cured product]
The cured product of the present invention is obtained by curing the curable resin composition of the present invention or the resin layer of the dry film of the present invention. The cured product of the present invention can be suitably used for printed wiring boards, electronic components, and the like. The cured product of the present invention is excellent in high crack resistance, high resolution, and dielectric properties including low dielectric constant and low dielectric loss tangent. Further, the cured product of the present invention is also excellent in heat resistance and coefficient of linear expansion.

[Printed circuit board]
The printed wiring board of the present invention has a cured product obtained from the curable resin composition of the present invention or the resin layer of a dry film. As a method for producing a printed wiring board of the present invention, for example, the curable resin composition of the present invention is adjusted to a viscosity suitable for the coating method using the above organic solvent, and a dip coating method is applied onto the substrate. After coating by a method such as a flow coating method, a roll coating method, a bar coater method, a screen printing method, or a curtain coating method, the organic solvent contained in the composition is volatilized and dried (temporarily dried) at a temperature of 60 to 100 ° C. As a result, a tack-free resin layer is formed. Further, in the case of a dry film, a resin layer is formed on the base material by sticking the resin layer on the base material with a laminator or the like so that the resin layer comes into contact with the base material, and then peeling off the carrier film.

The base material includes a printed wiring board and a flexible printed wiring board whose circuit is formed of copper or the like in advance, as well as paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / non-woven cloth epoxy, and glass cloth / paper epoxy. , Synthetic fiber epoxy, fluororesin / polyethylene / polyimideene ether, polyphenylene oxide / cyanate, etc. are used for high-frequency circuit copper-clad laminates, etc., and all grades (FR-4, etc.) of copper-clad laminates are used. Plates, other metal substrates, polyimide films, polyethylene terephthalate films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer plates and the like can be mentioned.

It is preferable that the dry film is attached to the substrate under pressure and heating using a vacuum laminator or the like. By using such a vacuum laminator, when a circuit-formed substrate is used, even if the surface of the circuit board is uneven, the dry film adheres to the circuit board, so that air bubbles are not mixed and the circuit board is not mixed. The hole filling property of the recesses on the surface of the substrate is also improved. The pressurizing condition is preferably about 0.1 to 2.0 MPa, and the heating condition is preferably 40 to 120 ° C.

Volatile drying performed after applying the curable resin composition of the present invention is carried out in a hot air circulation type drying oven, IR furnace, hot plate, convection oven, etc. (using a steam-based air heating type heat source in the dryer). It can be carried out by using a method of bringing hot air into countercurrent contact and a method of blowing hot air onto a support from a nozzle).

After forming a resin layer on the substrate, it is selectively exposed to active energy rays through a photomask having a predetermined pattern, and the unexposed portion is exposed to a dilute alkaline aqueous solution (for example, 0.3 to 3% by mass sodium carbonate aqueous solution). To form a pattern of the cured product. In the case of a dry film, after exposure, the support film is peeled off from the dry film and developed to form a patterned cured product on the substrate. The exposed resin layer may be exposed and developed by peeling the support film from the dry film before exposure as long as the characteristics are not impaired.

Further, the cured product is adhered by irradiating the cured product with active energy rays and then heat-curing (for example, 100 to 220 ° C.), or by irradiating the cured product with active energy rays after heat curing, or by performing final finish curing (main curing) only by heat curing. It forms a cured film with excellent properties such as properties and hardness.

The exposure machine used for the above-mentioned active energy ray irradiation may be a device equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc., and irradiates ultraviolet rays in the range of 350 to 450 nm. Further, a direct drawing device (for example, a laser direct imaging device that directly draws an image with a laser based on CAD data from a computer) can also be used. The lamp light source or the laser light source of the direct drawing machine may have a maximum wavelength in the range of 350 to 450 nm. The exposure amount for image formation varies depending on the film thickness and the like, but can be generally in the range of 10 to 1000 mJ / cm ² , preferably 20 to 800 mJ / cm ² .

The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and the developing solution includes potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, etc. Alkaline aqueous solutions such as ammonia and amines can be used.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples and Comparative Examples. In the following, "part" and "%" are all based on mass unless otherwise specified.

[Synthesis Example 1 (Synthesis of Carboxylic Acid Group-Containing Resin 1)]
Novolac type cresol resin (trade name "Shonol CRG951", manufactured by Aika Kogyo Co., Ltd., OH equivalent: 119.4) 119.4 mass in an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device. 1.19 parts by mass of potassium hydroxide and 119.4 parts by mass of toluene were introduced, and the inside of the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 parts by mass of propylene oxide was gradually added dropwise, and the mixture was reacted at 125 to 132 ° C. and 0 to 4.8 kg / cm ² for 16 hours. Then, the mixture was cooled to room temperature, and 1.56 parts by mass of 89% phosphoric acid was added to and mixed with the reaction solution to neutralize potassium hydroxide, and the solid content was 62.1% and the hydroxyl value was 182.2 mgKOH / g (307). A propylene oxide reaction solution of a novolak type cresol resin having a weight of .9 g / eq.) Was obtained. This was an average addition of 1.08 mol of propylene oxide per equivalent of phenolic hydroxyl group.

293.0 parts by mass of propylene oxide reaction solution of the obtained novolak type cresol resin, 43.2 parts by mass of acrylic acid, 11.53 parts by mass of methanesulfonic acid, 0.18 parts by mass of methylhydroquinone and 252.9 parts by mass of toluene. , Introduced into a reactor equipped with a stirrer, thermometer and air blowing tube, air was blown at a rate of 10 ml / min and reacted at 110 ° C. for 12 hours with stirring. As for the water produced by the reaction, 12.6 parts by mass of water was distilled off as an azeotropic mixture with toluene. Then, the mixture was cooled to room temperature, and the obtained reaction solution was neutralized with 35.35 parts by mass of a 15% aqueous sodium hydroxide solution, and then washed with water. Then, toluene was distilled off while substituting 118.1 parts by mass of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak type acrylate resin solution. Next, 332.5 parts by mass of the obtained novolak type acrylate resin solution and 1.22 parts by mass of triphenylphosphine were introduced into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and 10 ml / ml of air was introduced. While blowing at a rate of 1 minute and stirring, 60.8 parts by mass of tetrahydrophthalic anhydride was gradually added, reacted at 95 to 101 ° C. for 6 hours, cooled, and then taken out. In this way, a solution of the photosensitive carboxyl group-containing resin 1 having a solid content of 70.6% and an acid value of the solid content of 87.7 mgKOH / g was obtained.

[Synthesis Example 2 (Synthesis of Carboxylic Acid Group-Containing Resin 2)]
220 parts of cresol novolac type epoxy resin (manufactured by DIC Corporation, EPICLON N-695, epoxy equivalent: 220) is placed in a four-necked flask equipped with a stirrer and a reflux condenser, 214 parts of carbitol acetate is added, and heat-dissolved. did. Next, 0.1 part of hydroquinone as a polymerization inhibitor and 2.0 parts of dimethylbenzylamine as a reaction catalyst were added. The mixture was heated to 95-105 ° C., 72 parts of acrylic acid was gradually added dropwise, and the mixture was reacted for 16 hours. The reaction product was cooled to 80-90 ° C., 106 parts of tetrahydrophthalic anhydride was added, reacted for 8 hours, cooled and then removed. In this way, a solution of the carboxyl group-containing resin 2 having a solid content of 65% and an acid value of 100 mgKOH / g as a solid content was obtained.

[Preparation of curable resin composition]
Various components shown in Table 1 below are blended at the ratio (parts by mass) shown in Table 1 below, and 150 parts by mass of propylene glycol monomethyl ether acetate (PMA) is added as a solvent to dilute the mixture, and the mixture is prepared with a stirrer. After stirring, the mixture was kneaded with a 3-roll mill to prepare a curable resin composition.

In Table 1, the blending amount of each component is a numerical value in terms of solid content.
The details of each component in Table 1 are as follows.
* 1: The carboxyl group-containing resin 1 obtained in Synthesis Example 1
* 2: Carboxylic group-containing resin 2 obtained in Synthesis Example 2
* 3: Acylphosphine oxide-based photoinitiator (manufactured by IGM Resins, Omnirad TPO, 2,4,6-trimethylbenzoyldiphenylphosphine oxide)
* 4: Trifunctional epoxy resin having the structure of the above formula (I) (Techmore VG3101L manufactured by Printec Co., Ltd.)
* 5: Trifunctional aminophenol type epoxy resin that does not have the structure of the above formula (I) (manufactured by Mitsubishi Chemical Corporation, jER 630)
* 6: Phenolic novolac type epoxy resin (manufactured by Dow Chemical Co., Ltd., DEN431)
* 7: Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER 828)
* 8: Bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER 807)
* 9: Trifunctional epoxy resin (manufactured by DIC Corporation, N-770)
* 10: Non-aromatic ring liquid bifunctional epoxy resin (manufactured by ADEKA Corporation, EP-4088S)
* 11: Surface-treated silica (manufactured by Admatex Co., Ltd., SO-C2, average particle size 450 to 650 nm, methacrylic silane treatment)
* 12: Silica (manufactured by Admatex Co., Ltd., SO-C2, average particle size 450-650 nm, no surface treatment)
* 13: Hydroxyphenyltriazine-based UV absorber (BASF Japan Ltd., Tinuvin 477)
* 14: Dipentaerythritol hexaacrylate (Sanyo Chemical Industries, Ltd., Neomer DA-600)
* 15: Melamine * 16: Dicyandiamide * 17: Phthalocyanine blue * 18: Organic pigment

[Preparation of evaluation board]
Each curable resin composition was applied onto a cover film with an applicator and dried at 80 ° C. for 10 minutes to form a resin layer. The resin layer surface of this cover film is attached to the substrate with a laminator, solidly exposed at the optimum exposure amount using a DI exposure device, and a 1% by mass sodium carbonate aqueous solution at 30 ° C. is developed for 60 seconds under a spray pressure of 0.2 MPa. Was done. This substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure of 2000 mJ / cm ² , and then heated at 170 ° C. for 60 minutes to cure. The obtained evaluation substrate was evaluated as follows.

[EMC adhesion, failure mode evaluation]
Each curable resin composition was cured by laminating, full-exposure, developing, pre-UV, and post-curing on a FR-4 substrate with a copper foil under the above-mentioned preparation conditions for an evaluation substrate to prepare a substrate. The prepared substrate was subjected to plasma treatment using a plasma processing device (AP-1000 MARCH PLAZMA SYSTEMS, manufactured by INC.) Under the conditions of gas component Ar, gas pressure 200 mTorr, output 300 W, and plasma processing time 60 seconds. EMC (SG-8500BE SAMSUNG SDI) was formed at 5 mm ² on each cured coating film using an EMC mold press device (manufactured by MPC-06M APIC YAMADA CORPORATION). In the case of absorbing moisture, it was treated at 85 ° C./85% RH for 12 hours, and then pulled down using a small tabletop tester (FGS-500TV, manufactured by NIDEC-SHIMPO CORP.). Under these conditions, the rate of increase in adhesion was measured with and without plasma treatment and with or without moisture absorption.
The EMC adhesion was evaluated according to the following criteria, and the evaluation results are shown in Table 2.
(Evaluation criteria)
⊚: It was 150% or more.
◯: It was 140% or more and less than 150%.
X: It was less than 140%.
In addition, the evaluation of the fracture mode was carried out by observing the substrate after the EMC adhesion measurement with an optical microscope.
The destruction modes were evaluated according to the following criteria, and the evaluation results are shown in Table 2.
(Evaluation criteria)
◯: It was destroyed inside the SR.
X: It was peeled off at the interface.

[Heat resistance evaluation]
Each curable resin composition was formed on a copper foil substrate so as to have a film thickness of about 40 μm, and was exposed in a strip-shaped pattern of 50 mm × 3 mm. Then, development and curing were carried out under the same conditions as those for producing the standard evaluation plate.
The cured film of the evaluation substrate obtained as described above was peeled off from the copper foil, and Tg was measured using a TMA measuring device (model name: TMA6000 manufactured by Shimadzu Corporation).
The heat resistance was evaluated according to the following criteria, and the evaluation results are shown in Table 2.
(Evaluation criteria)
⊚: Tg was 180 ° C. or higher.
◯: Tg was 160 ° C. or higher and lower than 180 ° C.
X: Tg was less than 160 ° C.

[Insulation reliability evaluation]
A curable resin composition was formed so as to have a film thickness of about 20 μm on a substrate on which a comb-shaped pattern of L / S = 20/15 μm was formed, which was treated with CZ-8101B under the condition of an etching rate of 1.0 μm / m ^2. , Full exposure was performed. Then, development and curing were carried out under the same conditions as those for producing the standard evaluation substrate. Then, the electrodes were connected and the HAST test was carried out under the conditions of 130 ° C., 85%, 5V, 400 hours and n = 6.
The insulation reliability was evaluated according to the following criteria, and the evaluation results are shown in Table 2.
(Evaluation criteria)
⊚: n = 6 pass
◯: n = 3 pass
X: n = 0 pass

[Evaluation of opening stability]
A curable resin composition was formed on a plated copper substrate treated with CZ-8101B under a condition of an etching rate of 1.0 μm / m ² so as to have a film thickness of 15 μm, and exposure was performed with various aperture patterns. After that, development was carried out under predetermined conditions and curing was carried out under evaluation conditions.
The opening diameter of the evaluation substrate obtained as described above was observed, and it was confirmed that no halation or undercut occurred, and evaluation was performed.
Aperture stability was evaluated according to the following criteria, and the evaluation results are shown in Table 2. In addition, "-" in Table 2 indicates that it has not been evaluated.
(Evaluation criteria)
⊚: Stable and good aperture diameter within ± 2 μm error range at 50 μm (n = 3).
◯: At 50 μm, the opening diameter was stable and good within the error range of ± 5 μm (n = 3).

Claims (7)

A curable resin composition containing (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a surface-treated filler.
The (C) epoxy resin
(C1) The following formula (I):

Epoxy resin represented by
(C2) A curable resin composition containing a bisphenol A type, a bisphenol F type, or a phenol novolac type epoxy resin having less than trifunctionality. (E) The curable resin composition according to claim 1, further comprising an ultraviolet absorber. The surface-treated inorganic filler (D) has at least one photoreactive group selected from the group consisting of an acryloyl group, a metaacryloyl group, a vinyl group, a cyclic ether group, and a cyclic thioether group on the surface. The curable resin composition according to claim 1 or 2. A dry film comprising a support film and a resin layer formed on the support film and composed of a dry coating film of the curable resin composition according to any one of claims 1 to 3. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 3 or the resin layer of the dry film according to claim 4. A printed wiring board comprising the cured product according to claim 5. An electronic component comprising the printed wiring board according to claim 6.