JP6724097B2 - Curable resin composition, dry film, cured product, printed wiring board and electronic component - Google Patents

Description

The present invention relates to a curable resin composition, a dry film, a cured product, a printed wiring board and an electronic component.

In recent years, there has been an increasing demand for miniaturization in the field of semiconductor circuits and the like, and in order to meet the demand, semiconductor circuits may be mounted in a package (Chip Size Package) close to the chip size. As one of means for realizing a chip size package, a packaging method called a wafer level package (hereinafter, sometimes abbreviated as WLP) that joins and fragmentes at a wafer level has been proposed. The WLP is attracting attention because it can contribute to cost reduction and size reduction.
A permanent coating such as a solder resist used for such WLP is required to have high reliability for a long period of time, specifically, high insulation reliability. In particular, it is considered that the demand for reliability will further increase as the density of WLP becomes higher in the future.

Japanese Patent No. 5167113

However, regarding this reliability, for example, the conventional thermosetting resin composition for use in solder resist described in Patent Document 1 described above has become insufficient in recent years.
Further, in recent years, a solder resist in which a filler is highly filled in WLP has been used to improve crack resistance, and the composition tends to have a low elongation rate. Further, when a heat history such as reflow is given, the curing further progresses and the brittleness is likely to occur. Therefore, a large load is applied to the solder resist in the dicing process of the WLP individualization process, and defects such as delamination and chipping (chips) are likely to occur. Here, delamination means that the solder resist causes delamination. FIG. 1 shows an optical photograph of WLP delaminated in the dicing process. The white portion indicated by the arrow is the peeled portion of the solder resist.

Therefore, an object of the present invention is to provide a wafer level package while satisfying the performance required for a solder resist such as high adhesion, high resolution, high insulation reliability (HAST resistance), and high crack resistance (TCT resistance). A curable resin composition having high resistance to chipping, that is, a chipping-resistant curable resin composition, a dry film having a resin layer obtained from the curable resin composition, and the curable resin It is intended to provide a cured product of a composition or a resin layer of the dry film, a printed wiring board having the cured product, and an electronic component having the printed wiring board.

As a result of intensive research and development by the present inventors, by using a specific epoxy resin typified by the epoxy resin containing the isocyanuric ring and a specific defoaming agent or a leveling agent in combination, a wafer The present invention has been completed by finding that it is possible to obtain a curable resin composition having high chipping resistance, which is unlikely to cause defects due to delamination or chipping in the dicing process in the individualizing process of a level package. That is, the curable resin composition of the present invention comprises (A) a carboxyl group-containing resin, (B) an epoxy resin, (C) at least one of a silicone type or an acrylic copolymer type, a defoaming agent or a leveling agent, And (D) inorganic filler, and (B) epoxy resin having an epoxy equivalent of 180 g/eq. It is characterized in that it contains the following liquid non-aromatic epoxy resin.

In the curable resin composition of the present invention, the (B) epoxy resin preferably has an isocyanuric ring or a dicyclopentadiene skeleton, and the (D) inorganic filler content is 25 to 70 mass %. preferable.

The dry film of the present invention is characterized by having a resin layer obtained by applying the curable resin composition to a film and drying the film.
The cured product of the invention is characterized by being obtained by curing the curable resin composition or the resin layer of the dry film.
The printed wiring board of the present invention is characterized by having the above-mentioned cured product.
Furthermore, the electronic component of the present invention is characterized by having the above-mentioned printed wiring board.

According to the present invention, while satisfying the performance required for the solder resist such as high adhesion, high resolution, high insulation reliability (HAST resistance), and high crack resistance (TCT resistance), the wafer level package A curable resin composition that is less likely to cause defects due to delamination or chipping in the dicing step in the fragmentation process, that is, a chipping-resistant curable resin composition, a dry film having a resin layer obtained from the curable resin composition, and the curable resin composition A cured product of the resin or the resin layer of the dry film, a printed wiring board having the cured product, and an electronic component having the printed wiring board can be obtained.

It is an optical cross-sectional photograph of WLP delaminated in the dicing process.

The curable resin composition of the present invention comprises (A) a carboxyl group-containing resin, (B) an epoxy resin, (C) at least one of a silicone-based or acrylic copolymer-based defoaming agent or a leveling agent, and ( D) contains an inorganic filler, and (B) the epoxy resin has an epoxy equivalent of 180 g/eq. It is characterized in that it contains the following liquid non-aromatic epoxy resin.

As described above, the curable resin composition of the present invention has an epoxy equivalent of 180 g/eq. with an antifoaming agent or leveling agent of at least one of (C) silicone type and acrylic copolymer type. It is characterized in that it is used in combination with the following (B) epoxy resin which is a liquid non-aromatic epoxy resin.
(C) The antifoaming agent or leveling agent does not contribute to the curing by containing at least one of the silicone type and the acrylic copolymerization type, and the defoaming agent or the leveling agent is in a liquid state even after the curing. Therefore, the stress relaxation effect as a plasticizer can be expected.
Further, the epoxy equivalent is 180 g/eq. The epoxy resin (B), which is a liquid non-aromatic epoxy resin as described below, is unlikely to have a large thermal expansion coefficient and lowers the elastic modulus of the entire coating film, so that stress is less likely to occur.
Furthermore, (C) at least one of a silicone type and an acrylic copolymer type, an antifoaming agent or a leveling agent, and an epoxy equivalent of 180 g/eq. The following is a reasonably poor compatibility with (B) epoxy resin, which is a liquid non-aromatic epoxy resin, so a nanophase separation structure is formed and the defoaming agent or leveling agent is evenly dispersed in the system. , The stress relaxation effect is increased.
As described above, in the present invention, stress relaxation is achieved by using the defoaming agent or leveling agent of at least one of (B) epoxy resin and (C) silicon-based or acrylic copolymer-based resin having the above-mentioned characteristics. The effect can be enhanced. Therefore, the wafer level package is characterized in that defects due to delamination and chipping are less likely to occur in the dicing process in the individualizing process, that is, chipping resistance is high.

Below, each component of the curable resin composition of this invention is demonstrated. In addition, in this specification, (meth)acrylate is a general term for acrylates, methacrylates, and mixtures thereof, and the same applies to other similar expressions.

[(A) Carboxyl group-containing resin]
As the carboxyl group-containing resin, various conventionally known carboxyl group-containing resins having a carboxyl group in the molecule can be used. Particularly, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond in the molecule is preferable in terms of photocurability and development resistance. The ethylenically unsaturated double bond is preferably derived from acrylic acid or methacrylic acid or their derivatives. When using only a carboxyl group-containing resin having no ethylenically unsaturated double bond, in order to make the composition photocurable, a compound having a plurality of ethylenically unsaturated groups in the molecule described below, It is necessary to use a reactive monomer together.
Specific examples of the carboxyl group-containing resin include the following compounds (which may be either oligomers or polymers).

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

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

(3) Diisocyanate and a 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 ( A carboxyl group-containing photosensitive urethane resin obtained by a polyaddition reaction of (meth)acrylate or a partial acid anhydride modified product thereof, a carboxyl group-containing dialcohol compound and a diol compound.

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

(5) During the synthesis of the resin of the above (2) or (3), one isocyanate group and one or more (meth)acryloyl groups such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate are formed in the molecule. A carboxyl group-containing photosensitive urethane resin in which a compound having the above is added and the terminal (meth)acrylate is obtained.

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

(7) Carboxyl obtained by reacting (meth)acrylic acid with a polyfunctional epoxy resin obtained by epoxidizing a hydroxyl group of a bifunctional (solid) epoxy resin with epichlorohydrin and adding a dibasic acid anhydride to the generated hydroxyl group. 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 resulting primary hydroxyl group is a dibasic base such as phthalic anhydride, tetrahydrophthalic anhydride or hexahydrophthalic anhydride. A carboxyl group-containing polyester resin to which an acid anhydride has been 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) A maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipine is reacted with the alcoholic hydroxyl group of the reaction product obtained by reacting with an unsaturated group-containing monocarboxylic acid such as acrylic acid. A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride such as an acid.

(10) Reaction product obtained by reacting 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 with an unsaturated group-containing monocarboxylic acid A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(11) 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 a cyclic carbonate compound such as ethylene carbonate and propylene carbonate. A carboxyl group-containing photosensitive resin obtained by reacting a reaction 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 group in one molecule to the resin of (1) to (11).
In addition, in this specification, (meth)acrylate is a general term for acrylates, methacrylates, and mixtures thereof, and the same applies to other similar expressions.

The (A) carboxyl group-containing resin can be used without being limited to those listed above, and one kind may be used alone, or a plurality of kinds may be mixed and used. Among them, the carboxyl group-containing resins synthesized using a phenol compound such as the carboxyl group-containing resins (10) and (11) as a starting material have a HAST test under high voltage, that is, B-HAST resistance and PCT resistance. Since it is excellent, it can be preferably used.

The acid value of the (A) carboxyl group-containing resin is preferably 20 to 200 mgKOH/g. When the acid value of the (A) carboxyl group-containing resin is 20 to 200 mgKOH/g, it becomes easy to form a pattern of a cured product. More preferably, it is 50 to 130 mgKOH/g.

The weight average molecular weight of the (A) carboxyl group-containing resin varies depending on the resin skeleton, but it is generally preferably in the range of 2,000 to 150,000, and more preferably 5,000 to 100,000. When the weight average molecular weight is 2,000 or more, the development resistance of the coating film in the exposed area is improved and the resolution is excellent. On the other hand, when the weight average molecular weight is 150,000 or less, the solubility of the unexposed portion is good, the resolution is excellent, and the storage stability may be improved. The weight average molecular weight can be measured by gel permeation chromatography.

The compounding amount of the (A) carboxyl group-containing resin is, for example, 5 to 50% by mass, and preferably 10 to 40% by mass, based on the total amount of the curable resin composition excluding the solvent. The coating film strength can be improved by setting it to 5% by mass or more, preferably 10% by mass or more. Further, when the content is 50% by mass or less, the viscosity becomes appropriate and the workability is improved.

[(B) Epoxy resin]
The curable resin composition of the present invention has an epoxy equivalent of 180 g/eq. The following is included (B) epoxy resin which is a liquid non-aromatic epoxy resin. As described above, the epoxy resin (B) that satisfies this condition has a characteristic that the coefficient of thermal expansion is unlikely to be large and the elastic modulus of the entire coating film is lowered, so that stress is not easily generated, so that the condition is satisfied. As long as any known and commonly used epoxy resin can be used in the present invention, a resin having an isocyanuric ring or a dicyclopentadiene skeleton is preferable because it has a large effect of reducing the elastic modulus while suppressing an increase in the coefficient of linear thermal expansion.

Specific examples of the (B) epoxy resin having an isocyanuric ring include TEPIC, TEPIC-VL, TEPIC-FL, and TEPIC-UC manufactured by Nissan Kagaku Co., Ltd. Of these, TEPIC-VL is heat-resistant. Preferred for sex reasons. TEPIC-VL is an epoxy resin having the structure of the following formula (I), which is a colorless transparent liquid having a Gardner color number of 1 or less and is viscous, and has an epoxy equivalent of 135 g/eq. The total chlorine content is 200 ppm or less, high heat resistance, high light resistance, low water absorption and low curing shrinkage.

Specific examples of the (B) epoxy resin having a dicyclopentadiene skeleton include EP-4088S manufactured by ADEKA Corporation.

The curable resin composition of the present invention can contain an epoxy resin other than the above-mentioned (B) epoxy resin together with the above-mentioned (B) epoxy resin as long as the effect peculiar to the present invention is not impaired. Epoxy resins other than the above (B) epoxy resin include epoxidized vegetable oil; bisphenol A type epoxy resin; hydroquinone type epoxy resin; bisphenol type epoxy resin; thioether type epoxy resin; brominated epoxy resin; novolac type epoxy resin; biphenol novolac. Type epoxy resin; bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidyl amine type epoxy resin; hydantoin type epoxy resin; alicyclic epoxy resin; trihydroxyphenylmethane type epoxy resin; bixylenol type or biphenol type epoxy resin Resin or mixture thereof; Bisphenol S type epoxy resin; Bisphenol A novolac type epoxy resin; Tetraphenylolethane type epoxy resin; Heterocyclic epoxy resin; Diglycidyl phthalate resin; Tetraglycidyl xylenoyl ethane resin; Naphthalene group-containing epoxy Resins; epoxy resins having a dicyclopentadiene skeleton; glycidyl methacrylate copolymerization epoxy resins; cyclohexylmaleimide and glycidyl methacrylate copolymerization epoxy resins; epoxy-modified polybutadiene rubber derivatives; CTBN-modified epoxy resins and the like. It is not limited to.

The compounding amount of the (B) epoxy resin is, for example, 10 to 100 parts by mass, preferably 10 to 80 parts by mass, and more preferably 20 to 60 parts by mass, relative to 100 parts by mass of the (A) carboxyl group-containing resin. When the compounding amount of the epoxy resin (B) is 10 parts by mass or more, crack resistance and insulation reliability are further improved, and when it is 100 parts by mass or less, storage stability is improved.

[(C) Defoaming agent or leveling agent of at least one of silicon type and acrylic copolymer type]
The curable resin composition of the present invention contains (C) at least one of a silicone-based or acrylic copolymer-based antifoaming agent or leveling agent. As described above, the defoaming agent or leveling agent (C) of at least one of the silicone type and the acrylic copolymer type does not contribute to curing, remains in the system in a liquid state even after curing, and has the curability of the present invention. Since the compatibility with the (B) epoxy resin contained in the resin composition is moderately poor, a nanophase-separated structure is formed, and the defoaming agent or leveling agent is evenly dispersed in the system, so this condition is satisfied. Any known and commonly used epoxy resin can be used in the present invention as long as the above is satisfied, but an acrylic copolymer system is more preferable for the reason of adhesion.

Specifically, specific examples of the silicon-based defoaming agent or leveling agent include BYK-322, BYK-333 manufactured by BYK, and KS-66 manufactured by Shin-Etsu Chemical Co., Ltd., and acrylic. Specific examples of the copolymer-based defoaming agent or leveling agent include BYK-361N, BYK-1794, BYK-350, and BYK-1791 manufactured by BYK. Of these, BYK-361N and BYK-1794 is preferred for reasons of resistance to dicing and adhesion.

The compounding amount of the antifoaming agent or the leveling agent of (C) at least one of the silicone type and the acrylic copolymer type is 1 to 10 parts by mass based on 100 parts by mass of the (A) carboxyl group-containing resin. preferable. When the amount is 1 part by mass or more, the dicing resistance and the defoaming leveling property are excellent, and when the amount is 10 parts by mass or less, fusion prevention during DF laminating and resolution are good.

[(D) Inorganic filler]
The curable resin composition of the present invention contains (D) an inorganic filler. The inorganic filler is not particularly limited, and known conventional fillers such as silica, crystalline silica, Neuburg silica, aluminum hydroxide, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica, Inorganic fillers such as aluminum hydroxide, barium sulfate, barium titanate, iron oxide, non-fibrous glass, hydrotalcite, mineral wool, aluminum silicate, calcium silicate and zinc white can be used. Among them, silica is preferred, and spherical silica is more preferred because it has a small surface area and is less likely to be a starting point of cracks because stress is dispersed throughout.

The inorganic filler may be subjected to a photoreactive surface treatment so as to have a vinyl group, a styryl group, a methacrylic group, an acrylic group, etc. as a photocurable reactive group, and in this case, a methacrylic group, an acrylic group, a vinyl group. Groups are particularly preferred. Further, as the thermosetting reactive group, 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 May be subjected to a heat-reactive surface treatment, and in this case, an amino group and an epoxy group are particularly preferable. Furthermore, the inorganic filler (D) may have two or more curable reactive groups. As the inorganic filler (D), surface-treated silica is preferable. By including the surface-treated silica, the CTE can be lowered and the glass transition temperature can be raised.

(D) The method of introducing the curable reactive group into the surface of the inorganic filler is not particularly limited, and may be introduced by using a known and commonly used method. A surface treating agent having a curable reactive group, for example, a curing agent The surface of the inorganic filler may be treated with a coupling agent having a reactive group.

The surface treatment of the inorganic filler (D) is preferably a surface treatment with a coupling agent. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent or the like can be used. Of these, a silane coupling agent is preferable.

As the silane coupling agent, a silane coupling agent capable of introducing a curing reactive group into the inorganic filler (D) is preferable. Examples of the silane coupling agent capable of introducing the thermosetting reactive group include a silane coupling agent having an epoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, and a silane coupling agent having an isocyanate group. Examples of the agent include silane coupling agents having an epoxy group, and more preferred. As the silane coupling agent capable of introducing the photo-curing reactive group, a silane coupling agent having a vinyl group, a silane coupling agent having a styryl group, a silane coupling agent having a methacryl group, a silane coupling agent having an acrylic group The agent is preferable, and among them, the silane coupling agent having a methacryl group is more preferable.

When the surface treatment of the (D) inorganic filler is carried out, the surface-treated state may be blended in the curable resin composition of the present invention, and the surface-untreated (D) inorganic filler and the surface-treating agent are separately prepared. The (D) inorganic filler may be surface-treated in the composition by blending, but it is preferable to blend the (D) inorganic filler which has been surface-treated in advance. By blending the inorganic filler (D) that has been surface-treated in advance, it is possible to prevent a decrease in crack resistance and the like due to the surface-treating agent that has not been consumed in the surface treatment that may remain when blended separately. When preliminarily surface-treating, it is preferable to mix a preliminary dispersion liquid in which the (D) inorganic filler is preliminarily dispersed in a solvent or a resin component, and the surface-treated (D) inorganic filler is preliminarily dispersed in the solvent. It is more preferable that the pre-dispersion liquid is added to the composition after the surface-treatment is sufficiently performed when the surface-untreated (D) inorganic filler is pre-dispersed in the solvent.

In the curable resin composition of the present invention, the inorganic filler (D) preferably has an average particle size of 1 μm or less because it is more excellent in crack resistance. More preferably, it is 0.8 μm or less. In the present specification, the average particle size refers to the value of D _50, is a value measured using a Microtrac particle size analyzer manufactured by e.g. NIKKISO Corporation.

In addition, it is preferable that the inorganic filler (D) has a maximum particle size of 4.0 μm or less, since the reaction is efficiently performed, and crack resistance and adhesion are excellent. It is more preferably 3.0 μm or less. In addition, in this specification, the maximum particle size means a value of D ₁₀₀ , for example, a value measured using a Microtrac particle size analyzer manufactured by Nikkiso Co., Ltd.

The content of the inorganic filler is preferably 25 to 70% by mass, more preferably 30 to 60% by mass, and even more preferably 40 to 55% by mass based on the total amount of the solid content of the curable resin composition. More preferable.

(Photopolymerization initiator)
As the photopolymerization initiator, any photopolymerization initiator known as a photopolymerization initiator or a photoradical generator can be used, and for example, bis-(2,6-dichlorobenzoyl)phenylphosphine can be used. Fin 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 Such as -(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide and bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Omnirad 819 manufactured by IGM Resins). Bisacylphosphine oxides; 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphinic acid methyl ester, 2-methylbenzoyldiphenylphosphine Monoacylphosphine oxides such as fin oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Omnirad (Omnirad) TPO manufactured by IGM Resins); 1-hydroxy-cyclohexyl Phenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy 2-Methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one and other hydroxyacetophenones; benzoin, benzyl, benzoin Benzoins such as methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl ethers; benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, Benzophenones such as 4,4′-dichlorobenzophenone and 4,4′-bisdiethylaminobenzophenone; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloro Acetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) -Butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl)-1-[4-(4-morpholinyl)phenyl]-1-butanone, N,N-dimethylaminoacetophenone, etc. Acetophenones; thioxanthones such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, Anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, and 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; ethyl- Benzoic acid esters such as 4-dimethylaminobenzoate, 2-(dimethylamino)ethylbenzoate, p-dimethylbenzoic acid ethyl ester; 1,2-octanedione, 1-[4-(phenylthio)-,2-(O -Benzoyl oxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime), and other oxime esters; bis( η5-2,4-Cyclopentadiene-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium, bis(cyclopentadienyl)-bis[2,6 -Titanocenes such as difluoro-3-(2-(1-pyrr-1-yl)ethyl)phenyl]titanium; phenyldisulfide 2-nitrofluorene, butyroin, anisoinethyl ether, azobisisobutyronitrile, tetramethyl Examples thereof include thiuram disulfide. The photopolymerization initiators may be used alone or in combination of two or more. Among them, monoacylphosphine oxides and oxime esters are preferable, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3. -Yl]-, 1-(O-acetyloxime) is more preferred.

The compounding amount of the photopolymerization initiator is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin. When the amount is 0.5 parts by mass or more, the surface curability becomes good, and when the amount is 20 parts by mass or less, halation hardly occurs and good resolution is obtained.

(Compound having an ethylenically unsaturated bond)
The curable resin composition of the present invention may contain a compound having an ethylenically unsaturated bond, such as a photopolymerizable oligomer or a photopolymerizable vinyl monomer.

Examples of the photopolymerizable oligomer include unsaturated polyester oligomers and (meth)acrylate oligomers. Examples of (meth)acrylate oligomers include epoxy (meth)acrylates such as phenol novolac epoxy (meth)acrylate, cresol novolac epoxy (meth)acrylate, and bisphenol type epoxy (meth)acrylate, urethane (meth)acrylate, epoxy urethane (meth). ) Acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polybutadiene modified (meth)acrylate and the like.

As the photopolymerizable vinyl monomer, known and conventional ones, for example, styrene derivatives such as styrene, chlorostyrene and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate or vinyl benzoate; vinyl isobutyl ether, vinyl- Vinyl ethers such as n-butyl ether, vinyl-t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinyl cyclohexyl ether, ethylene glycol monobutyl vinyl ether, triethylene glycol monomethyl vinyl ether; acrylamide, (Meth)acrylamides such as methacrylamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, N-butoxymethylacrylamide; triallyl isocyanurate, diallyl phthalate, Allyl compounds such as diallyl isophthalate; 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, etc. (Meth)acrylic acid esters of hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, pentaerythritol tri(meth)acrylate; methoxyethyl (meth)acrylate, ethoxyethyl Alkoxyalkylene glycol mono(meth)acrylates such as (meth)acrylate; ethylene glycol di(meth)acrylate, butanediol di(meth)acrylates, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di( Alkylene polyols poly(meth)acrylates such as (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate; diethylene glycol di(meth)acrylate, triethylene glycol di Polyoxyalkylene glycol poly(meth)acrylates such as (meth)acrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane tri(meth)acrylate A) acrylates; hydroxypivalic acid neopentyl glycol ester di(meth)acrylate and other poly(meth)acrylates; tris[(meth)acryloxyethyl]isocyanurate and other isocyanurate-type poly(meth)acrylates Can be mentioned. These may be used alone or in combination of two or more according to the required characteristics.

The compounding amount of the compound having an ethylenically unsaturated bond is preferably 3 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin. When it is 3 parts by mass or more, surface curability is improved, and when it is 40 parts by mass or less, halation is suppressed. More preferably, it is 5 to 30 parts by mass.

(Thermosetting catalyst)
The curable resin composition of the present invention preferably contains a thermosetting catalyst. Examples of such a thermosetting catalyst include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. , Imidazole derivatives such as 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N -Amine compounds such as dimethylbenzylamine and 4-methyl-N,N-dimethylbenzylamine, hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide, and phosphorus compounds such as triphenylphosphine. Also, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino. S-triazine derivatives such as -S-triazine/isocyanuric acid adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid adduct can also be used, and preferably as the adhesion promoter. A compound that also functions is used in combination with a thermosetting catalyst.

The blending amount of the thermosetting catalyst is preferably 0.05 to 40 parts by mass, and more preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the (B) epoxy resin.

(Curing agent)
The curable resin composition of the present invention may contain a curing agent. Examples of the curing agent include phenol resins, polycarboxylic acids and acid anhydrides thereof, cyanate ester resins, active ester resins, maleimide compounds, alicyclic olefin polymers and the like. The curing agents may be used alone or in combination of two or more.

The curing agent has a ratio of a functional group capable of undergoing a thermosetting reaction such as an epoxy group of a thermosetting resin such as (C) epoxy resin and a functional group in the curing agent which reacts with the functional group, to the curing agent. It is preferable to mix them in such a ratio that the functional group/functional group capable of thermosetting reaction (equivalent ratio)=0.2 to 3. When the content is in the above range, the balance between storage stability and curability is excellent.

(Colorant)
The curable resin composition of the present invention may contain a colorant. As the colorant, known colorants such as red, blue, green, yellow, black and white can be used, and any of pigments, dyes and pigments may be used. However, it is preferable not to contain halogen from the viewpoint of reducing the environmental load and affecting the human body.

The amount of the colorant added is not particularly limited, but a ratio of preferably 10 parts by mass or less, particularly preferably 0.1 to 7 parts by mass is sufficient with respect to 100 parts by mass of the (A) carboxyl group-containing resin.

(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 carrier 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 tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether. , Glycol ethers such as dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbyl Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, solvent naphtha, etc. Conventional organic solvents can be used. These organic solvents can be used alone or in combination of two or more.

(Other optional ingredients)
Further, the curable resin composition of the present invention may be blended with other additives known and commonly used in the field of electronic materials. Other additives include thermal polymerization inhibitors, UV absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, antiaging agents, antibacterial and antifungal agents, antifoaming agents, leveling agents, thickening agents. Agents, adhesion promoters, thixotropic agents, photoinitiator aids, sensitizers, thermoplastic resins, organic fillers, mold release agents, surface treatment agents, dispersants, dispersion aids, surface modifiers, stabilizers , Phosphors, and the like.

The curable resin composition of the present invention may contain a thermosetting resin other than the epoxy resin (C) as long as the effect of the present invention is not impaired. The thermosetting resin may be any resin that is cured by heating and exhibits electrical insulation, and examples thereof include (C) epoxy compounds other than epoxy resin, oxetane compounds, melamine resins, and silicone resins. You may use these together.

The curable resin composition of the present invention may be used as a dry film or used as a liquid. When used as a liquid, it may be one-part or two-part or more.

Next, the dry film of the present invention has a resin layer obtained by applying the curable resin composition of the present invention on a carrier film and drying it. When forming a dry film, first, the curable resin composition of the present invention is diluted with the above organic solvent to adjust to an appropriate viscosity, and then a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater. , A reverse coater, a transfer roll coater, a gravure coater, a spray coater, etc. to apply a uniform thickness on the carrier film. Then, the applied composition is usually dried at a temperature of 40 to 130° C. for 1 to 30 minutes to form a resin layer. The coating film thickness is not particularly limited, but in general, the film thickness after drying is appropriately selected within a range of 3 to 150 μm, preferably 5 to 60 μm.

As the carrier film, a plastic film is used, and for example, a polyester film such as polyethylene terephthalate (PET), a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film or the like can be used. The thickness of the carrier film is not particularly limited, but generally, it is appropriately selected within the range of 10 to 150 μm. More preferably, it is in the range of 15 to 130 μm.

After forming a resin layer made of the curable resin composition of the present invention on a carrier film, for the purpose of preventing dust from adhering to the surface of the resin layer, the surface of the resin layer further has a peelable cover. It is preferable to laminate films. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, or the like can be used. Any cover film may be used as long as it has a smaller adhesive force between the resin layer and the carrier film when the cover film is peeled off.

In the present invention, a resin layer may be formed by applying the curable resin composition of the present invention on the cover film and drying the resin layer, and a carrier film may be laminated on the surface of the resin layer. That is, as the film to which the curable resin composition of the present invention is applied when producing the dry film in the present invention, either a carrier film or a cover film may be used.

The printed wiring board of the present invention has a curable resin composition of the present invention or a cured product obtained from a resin layer of a dry film. As the 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 a coating method using the organic solvent, and a dip coating method on a substrate, After applying 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 (temporary drying) at a temperature of 60 to 100°C. By doing so, a tack-free resin layer is formed. In the case of a dry film, the resin layer is formed on the substrate by sticking the resin layer on the substrate with a laminator or the like so that the resin layer contacts the substrate and then peeling off the carrier film.

Examples of the base material include a printed wiring board and a flexible printed wiring board on which circuits are previously formed of copper, paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth/non-woven cloth epoxy, glass cloth/paper epoxy. , Synthetic fiber epoxy, fluororesin/polyethylene/polyphenylene ether, polyphenylene oxide/cyanate, etc. copper clad laminates for high frequency circuits, etc., all grades (FR-4 etc.) Plates and the like, metal substrates, polyimide films, PET films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer plates and the like can be mentioned.

Volatile drying performed after applying the curable resin composition of the present invention, hot air circulation type drying furnace, IR furnace, hot plate, convection oven and the like (in the dryer using a heat source of air heating system by steam It is possible to use a method in which hot air is brought into countercurrent contact and a method in which hot air is blown onto the support from a nozzle).

After a resin layer is formed on the printed wiring board, it is selectively exposed to an active energy ray through a photomask on which a predetermined pattern is formed, and the unexposed portion is diluted with a dilute alkaline aqueous solution (for example, 0.3 to 3 mass% sodium carbonate aqueous solution). ) To form a cured product pattern. Further, the cured product is irradiated with an active energy ray and then heat-cured (for example, 100 to 220° C.), or after the heat-curing is irradiated with an active energy ray, or a final finish curing (main curing) is performed only by heat-curing, thereby achieving close contact. A cured film having excellent properties such as properties and hardness is formed.
When the curable resin composition of the present invention contains a photobase generator, it is preferably heated after exposure and before development. As heating conditions after exposure and development, for example, 60 to 150° C. It is preferable to heat for 60 minutes.

As the exposure machine used for the irradiation of active energy rays, a high-pressure mercury lamp lamp, an ultra-high-pressure mercury lamp lamp, a metal halide lamp, a mercury short arc lamp, or the like may be mounted, and an apparatus that irradiates ultraviolet rays in the range of 350 to 450 nm may be used. Further, a direct drawing device (for example, a laser direct imaging device that draws an image directly with a laser using CAD data from a computer) can also be used. A lamp light source or a laser light source for a 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 it can be generally in the range of 10 to 1000 mJ/cm ² , and preferably 20 to 800 mJ/cm ² .

The developing method may be a dipping method, a shower method, a spray method, a brush method, or the like, and as a developing solution, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, Aqueous alkaline solutions such as ammonia and amines can be used.

The curable resin composition of the present invention is preferably used for forming a cured film on a printed wiring board, more preferably used for forming a permanent coating, and more preferably a solder resist, Used to form an interlevel dielectric layer, coverlay. Further, according to the curable resin composition of the present invention, since it is possible to obtain a cured product having excellent crack resistance and insulation reliability, a printed wiring board having a fine pitch wiring pattern that requires high reliability, For example, it can be suitably used for forming a package substrate, particularly a permanent coating (especially solder resist) for FC-BGA.

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

[Synthesis of (A)-1 Carboxyl Group-Containing Resin]
In an autoclave equipped with a thermometer, a nitrogen introducing device and an alkylene oxide introducing device, and a stirrer, 119.4 parts of novolac-type cresol resin (SHONOL CRG951, Showa Denko KK, OH equivalent: 119.4), potassium hydroxide 1.19 parts and 119.4 parts of toluene were introduced, the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 parts of propylene oxide was gradually added dropwise and reacted at 125 to 132° C. and 0 to 4.8 kg/cm ² for 16 hours. Thereafter, the mixture was cooled to room temperature, and 1.56 parts of 89% phosphoric acid was added to and mixed with this reaction solution to neutralize potassium hydroxide, and the nonvolatile content was 62.1% and the hydroxyl value was 182.2 mgKOH/g (307. A propylene oxide reaction solution of a novolac type cresol resin having a concentration of 9 g/eq.) was obtained. This was an average of 1.08 mol of propylene oxide added per equivalent of the phenolic hydroxyl group.
The obtained propylene oxide reaction solution of novolac type cresol resin 293.0 parts, acrylic acid 43.2 parts, methanesulfonic acid 11.53 parts, methylhydroquinone 0.18 parts and toluene 252.9 parts were stirred with a stirrer and a temperature. It was introduced into a reactor equipped with a meter and an air blowing tube, air was blown at a rate of 10 ml/min, and the reaction was carried out at 110°C for 12 hours while stirring. The water produced by the reaction was an azeotropic mixture with toluene, and 12.6 parts of water was distilled out. Then, it was cooled to room temperature, the resulting reaction solution was neutralized with 35.35 parts of a 15% aqueous sodium hydroxide solution, and then washed with water. Then, toluene was distilled off while substituting 118.1 parts of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolac type acrylate resin solution. Next, 332.5 parts of the resulting novolac type acrylate resin solution and 1.22 parts of triphenylphosphine were introduced into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was supplied at a rate of 10 ml/min. Was blown in, and 60.8 parts of tetrahydrophthalic anhydride was gradually added while stirring, and the mixture was reacted at 95 to 101° C. for 6 hours, cooled, and taken out. Thus, a solution of the photosensitive (A)-1 carboxyl group-containing resin having a solid content of 65% and an acid value of the solid content of 87.7 mgKOH/g was obtained. Hereinafter, the solution of the carboxyl group-containing photosensitive resin is referred to as (A)-1 resin solution.

[(A)-2 Synthesis of Resin Containing Carboxyl Group]
Orthocresol novolac type epoxy resin (Epiclon N-695 manufactured by DIC Corporation, softening point 95°C, epoxy equivalent 214, average number of functional groups 7.6) 1070 g (number of glycidyl groups (total number of aromatic rings)) in 600 g of diethylene glycol monoethyl ether acetate: 5.0 mol), 360 g (5.0 mol) of acrylic acid, and 1.5 g of hydroquinone were charged, and the mixture was heated and stirred at 100° C. to be uniformly dissolved.
Then, 4.3 g of triphenylphosphine was charged, heated to 110° C. and reacted for 2 hours, then heated to 120° C. and further reacted for 12 hours. To the resulting reaction solution were charged 415 g of an aromatic hydrocarbon (Solvesso 150) and 456.0 g (3.0 mol) of tetrahydrophthalic anhydride, the reaction was carried out at 110° C. for 4 hours, the mixture was cooled, and the photosensitive ( A)-2 carboxyl group-containing resin solution was obtained. The resin solution thus obtained had a solid content of 65% and an acid value of the solid content of 89 mgKOH/g. Hereinafter, the solution of the carboxyl group-containing photosensitive resin is referred to as a resin solution (A)-2.

[Synthesis of (A)-3 Carboxyl Group-Containing Resin]
In a flask equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser, 325.0 parts of dipropylene glycol monomethyl ether as a solvent was heated to 110° C., and 174.0 parts of methacrylic acid and ε-caprolactone-modified methacrylic acid were added. (Average molecular weight 314) 174.0 parts, methyl methacrylate 77.0 parts, dipropylene glycol monomethyl ether 222.0 parts, and t-butyl peroxy 2-ethylhexanoate as a polymerization catalyst (Perbutyl O manufactured by NOF CORPORATION). ) 12.0 parts of the mixture was added dropwise over 3 hours and further stirred at 110°C for 3 hours to deactivate the polymerization catalyst to obtain a resin solution.
After cooling this resin solution, 289.0 parts of Cyclomer A200 manufactured by Daicel Chemical Industries, Ltd., 3.0 parts of triphenylphosphine and 1.3 parts of hydroquinone monomethyl ether were added, the temperature was raised to 100° C., and the mixture was stirred. Thus, the ring-opening addition reaction of the epoxy group was performed to obtain a photosensitive carboxyl group-containing resin solution.
The resin solution thus obtained had a weight average molecular weight (Mw) of 15,000, a solid content of 57%, and an acid value of the solid of 79.8 mgKOH/g. Hereinafter, the solution of the carboxyl group-containing photosensitive resin is referred to as a resin solution (A)-3.

(Examples 1 to 15, Comparative Examples 1 to 5 and Reference Examples 1 to 3)
Each of the components shown in Tables 1 to 3 was blended in the proportions shown in Tables 1 to 3 with respect to the carboxyl group-containing resins (mostly 100 parts by mass) of (A)-1 to 3 synthesized above. The curable resin composition for each of Comparative Example and Reference Example was passed through a drying furnace at 60 to 120° C. on PET using a die coater at 10 m/min, and a solvent was volatilized to obtain a dry film. In addition, the compounding amounts in Tables 1 to 3 are all numerical values in terms of solid matter.
The obtained dry film was laminated on a test substrate using a vacuum laminator CVP-300 (manufactured by Nikko Materials Co., Ltd.), and the curable resin compositions of Examples 1-15, Comparative Examples 1-5 and Reference Examples 1-3. A laminated body of was obtained. Here, since the test substrate and the laminating method differ depending on the evaluation items, they will be described in the section of each evaluation item below.
This laminate was subjected to pattern exposure using a DXP-3580 (manufactured by ORC, an ultrahigh pressure mercury lamp DI exposure machine) with a Stouffer 41 step tablet so that the curing step number was 10 according to the evaluation items. Exposure conditions other than this are different for each evaluation item, and therefore will be described in the section of each evaluation item below.
Ten minutes after the exposure, the PET film was peeled off, and development was carried out with a 1% by mass aqueous sodium carbonate solution at 30° C. for a development time twice the breakpoint (shortest development time). After that, by exposing at 2000 mJ with a UV conveyer (manufactured by ORC, metal halide lamp) and curing under conditions of 170° C. for 60 minutes in a heat cycle type Box furnace, Examples 1 to 15, Comparative Examples 1 to 5 and Reference Examples 1 to 1 The evaluation board|substrate of the curable resin composition of 3 was obtained. In addition, developing and curing under the developing and curing conditions described in this paragraph is described as "performing developing and curing under predetermined conditions" in each of the following evaluation item sections.

With respect to the evaluation substrates of the curable resin compositions of Examples 1 to 15, Comparative Examples 1 to 5 and Reference Examples 1 to 3 thus created, Tg, dicing resistance, discoloration resistance, curing inhibition by thermal history, adhesion , Resolution, HAST resistance and TCT resistance were evaluated. The evaluation results are also shown in Tables 1 to 3.

(Glass transition temperature Tg evaluation)
Each curable resin composition was formed on a copper foil substrate so as to have a film thickness of about 40 μm, and exposed with a strip-shaped pattern of 50 mm×3 mm. After that, development and curing were performed under predetermined conditions.
The cured film of the evaluation substrate obtained as described above was peeled from the copper foil, and Tg was evaluated. A TMA measuring device (manufactured by Shimadzu Corporation, model name: TMA6000) was used for the measurement. The evaluation criteria are as follows.
A: 180° C. or higher.
Good: 170°C or higher and lower than 180°C.
Δ: 160° C. or higher and lower than 170° C.
X: less than 160°C.

(Dicing resistance evaluation)
A curable resin composition was formed on an 8-inch wafer treated with AP8000 manufactured by Dow Chemical Co., so as to have a film thickness of about 15 μm, and the whole surface was exposed. After that, development and curing were performed under predetermined conditions. The obtained evaluation substrate was diced into a 5 mm square, and the occurrence rate of delamination was counted. The evaluation criteria are as follows.
⊚: No occurrence.
Good: Occurrence rate of less than 1%.
Δ: Occurrence rate of 1% or more and less than 5%.
X: Occurrence rate of 5% or more.

(Discoloration resistance)
A curable resin composition was formed on a glass substrate so as to have a film thickness of about 10 μm, and the entire surface was exposed. After that, development and curing were performed under predetermined conditions. The obtained evaluation substrate was measured with a spectrocolorimeter SPECTROPHOTOMER CM-2600d manufactured by Konica Minolta Co., Ltd., and color management software CM-S100W SpectraMagic NX ver. The result of performing the Lab value analysis in 2.6 is set as (1), and the result of performing the Lab value analysis in the same manner after curing the evaluation substrate obtained above again under the condition of 180° C. for 3 hours ( 2), and the evaluation was performed by the numerical difference between the b values of (1) and (2). The evaluation criteria are as follows.
A: Less than 2.0.
◯: 2.0 or more and less than 4.0.
Δ: 4.0 or more and less than 6.0.
X: 6.0 or more.

(Evaluation of curing inhibition by heat history)
Each curable resin composition was formed on a copper foil substrate so as to have a film thickness of about 40 μm, and exposed in a strip pattern of 50 mm×5 mm. After that, development and curing were performed under predetermined conditions.
The cured film of the evaluation substrate obtained as described above was peeled from the copper foil, and Tg was measured using DMA (RSA-G2 manufactured by TA Co.) as the result (1), and the evaluation obtained as described above. The substrate was cured again under the condition of 150° C. for 24 hours, then the cured coating of the evaluation substrate was peeled off from the copper foil in the same manner, and Tg was measured using DMA (RSA-G2 manufactured by TA Co.).
2), and the evaluation was performed by the numerical difference between (1) and (2). The evaluation criteria are as follows.
A: Less than 15°C.
◯: 15°C or higher and lower than 30°C.
Δ: 30°C or higher and lower than 45°C.
X: 45° C. or higher.

(Adhesion evaluation)
A curable resin composition was formed on a copper foil treated with CZ-8201B at an etching rate of 0.5 μm/m ² so as to have a film thickness of about 20 μm, and the entire surface was exposed. After that, development and curing were performed under predetermined conditions. Then, a thermosetting adhesive Araldite (manufactured by Nichiban Co., Ltd.) was formed on the surface of the curable resin composition, adhered to the FR-4 substrate and cured under the condition of 80° C. for 6 hours. After that, the evaluation substrate was cut at intervals of 20 mm, and both sides were peeled off so that the Cu foil width became 10 mm, to produce an evaluation strip. This evaluation strip was subjected to a 90° peel test using a tensile tester (model name: AGS-G 100N manufactured by Shimadzu Corporation) to evaluate the adhesion. The evaluation criteria are as follows.
A: 6.0 N/cm or more.
◯: 5.0 or more and less than 6.0 N/cm.
Δ: 4.0 or more and less than 5.0 N/cm.
X: Less than 4.0 N/cm.

(Resolution evaluation)
A curable resin composition was formed to a film thickness of about 15 μm on a plated copper substrate treated with CZ-8101B at an etching rate of 1.0 μm/m ² , and exposed with various opening patterns. After that, development was performed under predetermined conditions and curing was performed under evaluation conditions.
The opening diameter of the evaluation substrate obtained as described above was observed, and it was confirmed that halation and undercut did not occur and evaluated. The evaluation criteria are as follows.
⊚: A good opening diameter of 60 μm.
◯: Good opening diameter at 70 μm.
Δ: A good opening diameter at 80 μm.
X: A good opening diameter cannot be obtained at 80 μm. Or development is not possible.

(HAST resistance evaluation)
The curable resin composition was applied to a substrate having a comb-shaped pattern of L/S=20/15 μm, which was treated with CZ-8101B at an etching rate of 1.0 μm/m ² , so that the film thickness on Cu was about 15 μm. It was formed and exposed over the entire surface. After that, development and curing were performed under predetermined conditions.
After that, the electrodes were connected and a HAST test was performed under the conditions of 130° C., 85%, and 5V. The evaluation criteria are as follows.
◎: Pass in 400 hours.
○: Pass in 350 hours.
Δ: Pass in 300 hours.
X: NG within 250 hours.

(TCT resistance)
A curable resin composition was formed on a package substrate treated with CZ-8101B at an etching rate of 1.0 μm/m ² so that the film thickness on Cu was about 15 μm, and SRO was exposed to 80 μm on a copper pad. It was After that, development and curing were performed under predetermined conditions. Then, Au plating treatment, solder bump formation, and Si chip mounting were carried out to obtain an evaluation board.
The evaluation substrate obtained as described above was placed in a thermal cycler in which a temperature cycle was performed between -65°C and 150°C, and TCT (Thermal Cycle Test) was performed. Then, the surface of the cured film was observed at 600 cycles, 800 cycles and 1000 cycles. The criteria for judgment are as follows.
A: No abnormality after 1000 cycles.
◯: No abnormality after 800 cycles Cracks occur after 1000 cycles.
B: No abnormality after 600 cycles. Cracks occur after 800 cycles.
X: Cracks occurred at 600 cycles.

The components used in Examples, Comparative Examples and Reference Examples described in Tables 1 to 3 are as follows.
(*1): the above-mentioned (A)-1 carboxyl group-containing resin (carboxylic acid equivalent 640)
(*2): the above-mentioned (A)-2 carboxyl group-containing resin (carboxylic acid equivalent 630)
(*3): the above-mentioned (A)-3 carboxyl group-containing resin (carboxylic acid equivalent 703)
(*4): Nissan Chemical Co., Ltd. TEPIC-VL (epoxy equivalent 135, isocyanuric ring-containing)
(*5): PETG manufactured by Showa Denko KK (liquid epoxy resin with an epoxy equivalent of 96)
(*6): EP-4088S manufactured by ADEKA Corporation (liquid epoxy resin, epoxy equivalent 170, dicyclopentadiene skeleton)
(*7): KHE-8000H manufactured by Nippon Kayaku Co., Ltd. (liquid epoxy resin, epoxy equivalent 170, special epoxy resin having silsesquioxane skeleton)
(*8): Celloxide 2021P manufactured by Daicel Corporation (liquid epoxy resin, epoxy equivalent 130, alicyclic type)
(*9): N-770 (solid polyfunctional epoxy resin, epoxy equivalent 176, phenol novolac type) manufactured by DIC Corporation.
(*10): HP-7200L manufactured by DIC Corporation (solid polyfunctional epoxy resin, epoxy equivalent 247, phenol novolac type)
(*11): Mitsubishi Chemical Corporation jER828 (liquid epoxy resin, epoxy equivalent 189, bisphenol A type skeleton)
(*12): BYK-361N manufactured by BYK (leveling agent, acrylic copolymer system)
(*13): BYK-1794 (defoaming agent, acrylic copolymer system) manufactured by BYK Co., Ltd.
(*14): BYK-made BYK-322 (leveling agent, silicon type)
(*15): Shin-Etsu Chemical Co., Ltd. KS-66 (antifoaming agent, silicone type)
(*16): F-563 (anti-foaming/leveling agent, fluorine-based) manufactured by DIC Corporation
(*17): RS-72-K (antifoaming/leveling agent, fluorine type) manufactured by DIC Corporation
(*18): Silica dispersion obtained by the following manufacturing method. 50 g of spherical silica particles (SFP-20M manufactured by Denka Corp., average particle size: 400 nm), 48 g of PMA as a solvent, and 2 g of a dispersant (BYK-111) were uniformly dispersed.
(*19): Barium sulfate-dispersed product obtained by the following production method. After heating 50 g of an aqueous slurry of barium sulfate particles (precipitable barium 100 manufactured by Sakai Chemical Industry Co., Ltd.) to 70° C., a 10% sodium silicate aqueous solution was added to silica particles in an amount of 1% in terms of silica particles. Hydrochloric acid was added to this slurry to adjust the pH to 4 and aged for 30 minutes. Further, while maintaining the pH at 7±1 with hydrochloric acid, a 20% sodium aluminate (NaAlO ₂ ) aqueous solution was added to silica particles to form alumina ( 5% was added in terms of Al ₂ O ₃ ). Then, a 20% sodium hydroxide aqueous bath solution was added to adjust the pH to 7, and the mixture was aged for 30 minutes. Then, the slurry was filtered, washed with water using a filter press, and dried in vacuum to obtain a solid product of barium sulfate particles coated with a hydrated oxide of silicon and a hydrated oxide of aluminum. 50 g of barium sulfate particles coated with a hydrated oxide of silicon obtained in the same manner as above, 48 g of PMA as a solvent, and 2 g of a dispersant (BYK-111) were uniformly dispersed.
(*20): An alumina dispersed product obtained by the following manufacturing method. 50 g of spherical alumina particles (ASFP-20 manufactured by Denka Corp., average particle diameter: 300 nm), 48 g of PMA as a solvent, and 2 g of a dispersant (BYK-111) were uniformly dispersed.
(*21): A silica dispersion obtained by the following manufacturing method. 50 g of spherical silica particles (SFP-20M manufactured by Denka Co., average particle size: 400 nm), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacryl group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) are uniformly dispersed. Let
(*22): Silica dispersion obtained by the following manufacturing method. After heating 50 g of an aqueous slurry of spherical silica particles (SFP-20M manufactured by Denka Co., Ltd., average particle size: 400 nm) to 70° C., a 10% sodium silicate aqueous solution is added to the silica particles in an amount of 1% in terms of silica particles. Was added. Hydrochloric acid was added to this slurry to adjust the pH to 4 and aged for 30 minutes. Further, while maintaining the pH at 7±1 with hydrochloric acid, a 20% sodium aluminate (NaAlO ₂ ) aqueous solution was added to silica particles to form alumina ( 5% was added in terms of Al ₂ O ₃ ). Then, a 20% sodium hydroxide aqueous bath solution was added to adjust the pH to 7, and the mixture was aged for 30 minutes. After that, the slurry was filtered, washed with water using a filter press, and vacuum dried to obtain a solid substance of silica particles coated with a hydrated oxide of silicon and a hydrated oxide of aluminum. 50 g of silica particles coated with a hydrated oxide of silicon obtained in the same manner as above, 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacryl group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) were uniformly added. Dispersed.
(*23): OmniradTPO manufactured by IGM Resins (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide)
(*24): BASF Japan KK Irgacure OXE02 (ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(o-acetyloxime)
(*25): Nippon Kayaku Co., Ltd. DPHA (dipentaerythritol hexaacrylate)
(*26): Phthalocyanine blue (*27): Chromophthal yellow (*28): Melamine (*29): DICY (dicyandiamide)

From the results shown in Tables 1 to 3, according to the curable resin composition of the present invention, a solder resist having high adhesion, high resolution, high insulation reliability (HAST resistance), and high crack resistance (TCT resistance) can be obtained. While satisfying the required performance, it can be seen that a curable resin composition having a high chipping resistance can be obtained in which a defect due to delamination or chipping is less likely to occur in the dicing process in the wafer level package dicing process. ..

Claims (6)

(A) Carboxyl group-containing resin,
(B) It has an isocyanuric ring or a dicyclopentadiene skeleton, and has an epoxy equivalent of 180 g/eq. A liquid non-aromatic epoxy resin, which is
(C) at least one of a silicon-based or acrylic copolymer type, that Yusuke said epoxy resin (B) anti-foaming agent or a leveling agent in liquid form after curing remain in the system in, and (D) containing an inorganic filler A curable resin composition comprising: The curable resin composition according to claim 1, wherein the content of the (D) inorganic filler is 25 to 70% by mass. A dry film having a resin layer obtained by applying the curable resin composition according to claim 1 or 2 to a film and drying the film. A curable resin composition according to claim 1 or 2 , or a cured product obtained by curing the resin layer of the dry film according to claim 3 . A printed wiring board comprising the cured product according to claim 4 . An electronic component comprising the printed wiring board according to claim 5 .