WO2022050372A1 - Photocurable thermosetting resin composition, dry film, cured product, and electronic component comprising cured product - Google Patents

Abstract

[Problem] To provide: a photocurable thermosetting resin composition that stores exceptionally well, that leads to minimal adverse events such as pinholes and cissing in a resulting dry film, and that has exceptional electrical characteristics; a cured product of said resin composition; and an electronic component comprising said cured product. [Solution] A photocurable thermosetting resin composition composed of a resin composition of at least a two-liquid system and containing an epoxy resin (A), a carboxyl group-containing resin (B), a photopolymerization initiator (C), a photosensitive monomer (D), silica (E), barium sulfate (F), and an organic solvent, the photocurable thermosetting resin composition characterized in that a resin composition of at least a two-liquid system is used to obtain the photocurable thermosetting resin composition, the carboxyl group-containing resin (B), the photosensitive monomer (D), and the silica (E) are contained in a separate resin composition from the epoxy resin (A), the barium sulfate (F), and the photopolymerization initiator (C), and the resin composition containing the photopolymerization initiator (C) has an organic solvent capable of dissolving the photopolymerization initiator (C); a cured product obtained from said curable composition; and an electronic component comprising said cured product.

Description

Photocurable thermosetting resin compositions, dry films, cured products and electronic components containing the cured products

The present invention relates to a photocurable thermosetting resin composition, a dry film, a cured product, and an electronic component having the cured product. In particular, the present invention relates to a photocurable thermosetting resin composition consisting of at least a two-component system, a cured product thereof suitable for a printed wiring board, for example, a solder resist, and an electronic component having the cured product.

Conventionally, in printed wiring boards, solder resist has been used as a protective material for wiring board circuits, and high solder heat resistance and electrical insulation are required. As an example of the material composition, for example, alkali-developing type light. Examples thereof include curable thermosetting resin compositions.
As a component of such a photocurable thermosetting resin composition, a photosensitive polymer having a carboxyl group is mainly contained as a material, but in order to enhance the solder heat resistance of the cured product obtained after curing the composition. In addition, an epoxy resin may be contained. However, since the epoxy resin is relatively easy to react with the photosensitive polymer having a carboxyl group, there is a problem in long-term storage as a composition. Therefore, in general, a method has been used in which a two-component system in which easily reactive components are blended into different compositions is prepared, and they are mixed at the time of use to prepare a photocurable thermosetting resin composition.

Japanese Patent No. 5688116

By the way, in recent years, the density of printed wiring boards has been remarkably increased, and the minimum circuit size is 10 μm for lines and 10 μm for spaces, and higher insulation reliability than before is required. Due to the high density of the printed circuit board, insoluble substances (inorganic filler, crystalline epoxy resin, etc.) exist as particles between the fine pattern circuits, which causes a short circuit between the circuits.
When a dry film is prepared by applying and drying a two-component photocurable thermosetting resin composition on a carrier film, the resin compositions of the two liquids stored for one month after preparation are used. After mixing, when applied to the carrier film, the coarse particles that are thought to have been generated during the storage period of those resin compositions stored in separate containers cause cissing and pinholes for a long period of time. There was also a problem with storage stability.

On the other hand, for example, Patent Document 1 discloses that, among the constituents of a photocurable thermosetting resin composition, an epoxy resin is focused on to prevent the generation of coarse particles. ..
However, as described above, the density of the printed wiring board is remarkably increased, and the photocurable thermosetting resin composition is required to have higher insulation reliability, and coarse particles due to various factors as well as the epoxy resin are required. There is a demand for further improvement in electrical characteristics (HAST resistance) by suppressing the occurrence of.
In addition, from the viewpoint of securing inventory, even if one month has passed after each resin composition was produced, the generation of coarse particles due to various factors as well as the epoxy resin was suppressed, and pinholes were generated in the dry film production process. It is desirable to obtain long-term storage stability, such as suppressing the occurrence of pinholes and pinholes.

Therefore, an object of the present invention is to have excellent electrical characteristics (HAST resistance) of the cured product, good long-term storage stability, and at least 2 that can suppress the occurrence of cissing and pinholes in the dry film manufacturing process. It is an object of the present invention to provide a photocurable thermosetting resin composition which is composed in a liquid system.
Further, an object of the present invention is a dry film and a cured product having excellent various properties as described above obtained by using such an alkali-developed solder resist composition, and a solder resist and the like depending on the dry film and the cured product. It is an object of the present invention to provide a printed wiring board on which a cured film is formed.

As a result of diligent studies by the present inventor, the above-mentioned problems are (A) epoxy resin, (B) carboxyl group-containing resin, (C) photopolymerization initiator, (D) photosensitive monomer, (E) silica, (F). A photocurable thermosetting resin composition containing barium sulfate and.
In order to obtain the photocurable thermosetting resin composition, the resin composition is composed of at least two liquids.
The (B) carboxyl group-containing resin, the (D) photosensitive monomer, and the (E) silica are different from the (A) epoxy resin, the (F) barium sulfate, and the (C) photopolymerization initiator. Included in the resin composition of
The resin composition containing the (C) photopolymerization initiator is composed of at least two liquids and is photocurable, characterized by containing an organic solvent capable of dissolving the (C) photopolymerization initiator. It has been found that it can be solved by a thermosetting resin composition, and the present invention has been completed.
Of these, a preferred embodiment of the present invention is characterized by containing three types of the (A) epoxy resin, a semi-solid or solid epoxy resin at room temperature, a biphenyl type epoxy resin, and a novolak type. The present invention relates to a thermosetting resin composition.
A more preferable aspect of the present invention is that the composition containing the epoxy resin (A) has a viscosity of 4 dPa · s or less, and the photocurable thermosetting obtained by mixing the respective resin compositions. The present invention relates to a photocurable thermosetting resin composition, wherein the resin composition has a viscosity of 4 dPa · s or less.
In an even more preferable aspect of the present invention, the composition containing the (A) epoxy resin contains the (C) photopolymerization initiator and the organic solvent, with respect to 1 part by mass of the (C) photopolymerization initiator. The present invention relates to a photocurable thermosetting resin composition, which comprises 3 parts by mass or more of the organic solvent.
Another aspect of the present invention relates to a dry film having a film thickness of 10 μm to 30 μm, which is obtained by applying and drying the above-mentioned photocurable thermosetting resin composition on a carrier film.
Yet another aspect of the present invention also relates to the photocurable thermosetting resin composition described above, which is characterized by being used as a material for a solder resist.
Yet another aspect of the present invention is characterized in that it is obtained by curing a resin layer of a cured product or a dry film, which is obtained by curing a photocurable thermosetting resin composition. The present invention relates to a cured product and an electronic component having the cured product thereof.

According to the present invention, the cured product obtained by curing the photocurable thermosetting resin composition has excellent electrical characteristics (HAST resistance), and each resin composition has good long-term storage stability and is dry. It is possible to provide a photocurable thermosetting resin composition composed of at least a two-component system capable of suppressing the generation of cissing and pinholes in the film manufacturing process.
Further, according to the present invention, a dry film and a cured product having excellent various properties as described above obtained by using such a photocurable thermosetting resin composition, and a solder resist using the dry film and the cured product. It is possible to provide an electronic component such as a printed wiring board on which a cured film such as the above is formed.

The photocurable thermosetting resin composition of the present invention is preferably composed of at least a two-component resin composition. For example, a two-component system in which one resin composition is used as a main agent composition and the other resin composition is used as a curing agent composition can be mentioned. In this case, for example, the main agent composition may be composed of (B) a carboxyl group-containing resin, (D) a photosensitive monomer, (E) silica, and, if necessary, an organic solvent, as a curing agent composition. , (A) Epoxy resin, (C) Photopolymerization initiator, (F) Barium sulfate and (C) Photopolymerization initiator are preferably composed of a soluble organic solvent.
Here, from the viewpoint of preventing a chemical reaction during the storage period, (A) an epoxy resin and (B) a carboxyl group-containing resin, and (D) a photosensitive monomer and (C) a photopolymerization initiator are used, respectively. It is preferably contained in separate compositions. In addition, separation of the liquid surface of each composition (color floating / color separation), so-called Benard cell, may occur, which may impair the appearance of the liquid surface of each composition. Therefore, (E) silica and (F) barium sulfate are also used. Further, it is preferable that the components are separately contained in different compositions.
Further, if (B) a carboxyl group-containing resin and (C) a photopolymerization initiator are used in the same composition, the detailed mechanism is unknown, but the appearance of the composition may be poor and coarse particles may occur. The composition containing the carboxyl group-containing resin is preferably contained in a composition different from that of the (C) photopolymerization initiator and the organic solvent for dissolving the photopolymerization initiator.
Furthermore, the composition containing the epoxy resin (A) has a viscosity of 4 dPa · s or less, and the photocurable thermosetting resin composition obtained by mixing the respective resin compositions is 0. Having a viscosity of 1 dPa · s or more and 4 dPa · s or less is preferable because the precipitation of the (A) epoxy resin can be suppressed. When the viscosity of the composition containing (A) epoxy resin is 0.1 dPa · s or more, it is preferable that the composition is easy to handle.

Hereinafter, each component constituting the photocurable thermosetting resin composition of the present invention will be described.

[(A) Epoxy resin]
(A) The epoxy resin functions as a thermosetting component in the photocurable thermosetting resin composition and forms a cured product.
As such (A) epoxy resin, a known and commonly used polyfunctional epoxy resin having at least two epoxy groups in one molecule can be used.
(A) The epoxy resin may be liquid, or may be solid or semi-solid.
The polyfunctional epoxy resin includes bisphenol A type epoxy resin; brominated epoxy resin; novolak type epoxy resin; bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidylamine type epoxy resin; hydride-in type epoxy resin; oil ring. Formula epoxy resin; trihydroxyphenylmethane type epoxy resin; bixilenol type or biphenol type epoxy resin or a mixture thereof; bisphenol S type epoxy resin; bisphenol A novolak type epoxy resin; tetraphenylol ethane type epoxy resin; heterocyclic epoxy Resin; diglycidyl phthalate resin; tetraglycidyl xylenoyl ethane resin; naphthalene group-containing epoxy resin; epoxy resin having a dicyclopentadiene skeleton; glycidyl methacrylate copolymerized epoxy resin; cyclohexyl maleimide and glycidyl methacrylate copolymerized epoxy resin ; Epoxy-modified polybutadiene rubber derivative; CTBN-modified epoxy resin, epoxy resin having an isocyanul ring, and the like are preferable, but of course, the present invention is not limited thereto.
These epoxy resins can be used alone or in combination of two or more.
As the epoxy resin, it is preferable to use a novolak type epoxy resin as opposed to a semi-solid or solid epoxy resin and a biphenyl type epoxy resin at room temperature. By using these epoxy resins together, it is possible to suppress the generation of repellents and pinholes during the formation of a dry film. Further, as the solid epoxy resin, an epoxy resin having a dicyclopentadiene skeleton is particularly preferable because it has a low water absorption rate and is excellent in electrical characteristics. The mixing ratio of the novolak type epoxy resin to the semi-solid or solid epoxy resin or biphenyl type epoxy resin at room temperature is as follows: semi-solid or solid epoxy resin at room temperature: biphenyl type epoxy resin: novolak type epoxy resin = 1. 1: 1.5 is preferable, and more preferably 1: 1: 2.

As the component (A), a known and commonly used “epoxy resin that is solid or semi-solid at room temperature” can be used. For example, examples of the epoxy resin solid at room temperature include bisphenol A type epoxy resin (jER1001 manufactured by Mitsubishi Chemical Co., Ltd.), bisphenol F type epoxy resin (jER4004P manufactured by Mitsubishi Chemical Co., Ltd.), and naphthalene type epoxy resin (DIC Co., Ltd.). HP-4700), Naphthalene skeleton-containing polyfunctional solid epoxy resin (NC-7000 manufactured by Nippon Kayaku Co., Ltd.), Trisphenol epoxy resin (EPPN-502H manufactured by Nihon Kayaku Co., Ltd.), Dicyclopentadiene skeleton-containing Functional solid epoxy resin (Epiclon HP-7200 manufactured by DIC Co., Ltd.), phosphorus-containing epoxy resin (TX0712 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), Tris (2,3-epoxypropyl) isocyanurate (manufactured by Nissan Chemical Industry Co., Ltd.) TEPIC), examples of the epoxy resin that is semi-solid at room temperature include bisphenol A type epoxy resin (jER834 manufactured by Mitsubishi Chemical Co., Ltd.) and naphthalene type epoxy resin (HP-4032 manufactured by DIC Co., Ltd.).
Here, in the present invention, solid or semi-solid at room temperature means to exhibit solid or semi-solid at 15 ° C. The determination of solid or semi-solid can be performed in accordance with the "Liquid Confirmation Method" of Attachment 2 of the Ministerial Ordinance on Dangerous Goods Testing and Properties (Ministerial Ordinance No. 1 of 1989).
As the biphenyl type epoxy resin in the component (A), a known and commonly used polyfunctional epoxy resin having a biphenyl skeleton can be used. For example, a biphenyl skeleton-containing polyfunctional solid epoxy resin (NC-3000H, NC-3000 manufactured by Nippon Kayaku Co., Ltd.), a biphenyl type epoxy resin (YX-4000, YL-6121HA manufactured by Mitsubishi Chemical Corporation), and the like can be mentioned. ..
Examples of the novolak type epoxy resin in the component (A) include cresol novolak type epoxy resin (Epicron N-690 manufactured by DIC Corporation), phenol novolac type epoxy resin (Epicron N-770 manufactured by DIC Corporation), and Mitsubishi Chemical Co., Ltd. jER152) and the like.

The content of the (A) epoxy resin as described above is preferably in the range of about 30 to 60 parts by mass, preferably in the range of 35 to 45 parts by mass with respect to 100 parts by mass of the following (B) carboxyl group-containing resin. Is more preferable.

[(B) Carboxyl group-containing resin]
The (B) carboxyl group-containing resin used in the present invention has a carboxyl group in the molecule and does not have an ethylenically unsaturated group (non-photosensitive) or has this (photosensitive). Various conventionally known carboxyl group-containing resins can be used.

Specific examples of the carboxyl group-containing resin having no ethylenically unsaturated group include the following compounds (either oligomer or polymer).

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

(2) Carboxyl group-containing urethane resin by double addition reaction of diisocyanate and carboxyl group-containing dialcohol compound.

(3) 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, and isobutylene.

(4) A dicarboxylic acid such as adipic acid, phthalic acid, or hexahydrophthalic acid is reacted with a bifunctional epoxy resin or a bifunctional oxetane resin, and the generated hydroxyl group is subjected to phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, or the like. A carboxyl group-containing polyester resin to which a dibasic acid anhydride is added.

(5) A carboxyl group-containing resin obtained by opening an epoxy resin or an oxetane resin and reacting the generated hydroxyl group with a polybasic acid anhydride.

(6) A polybasic acid anhydride is added to a reaction product such as a polyalcohol resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule, that is, a polyphenol compound, with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing resin obtained by reacting with.

Further, specific examples of the carboxyl group-containing resin having an ethylenically unsaturated group include the following compounds (either oligomer or polymer). The ethylenically unsaturated bond in the carboxyl group-containing resin is preferably derived from acrylic acid, methacrylic acid or a derivative thereof.

(7) Dialcohol compounds, polycarbonate-based polyols, which contain diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and carboxyl groups such as dimethylolpropionic acid and dimethylolbutanoic acid. Containing carboxyl group by double addition reaction of diol compound such as polyether polyol, polyester polyol, polyolefin polyol, acrylic polyol, bisphenol A alkylene oxide adduct diol, compound having phenolic hydroxyl group and alcoholic hydroxyl group Photosensitive urethane resin.

(8) 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 produced by a double addition reaction of an acrylate or a partially acid anhydride-modified product thereof and a carboxyl group-containing dialcohol compound.

(9) During the synthesis of the above-mentioned resin (7) or (8), a compound having one hydroxyl group and one or more (meth) acryloyl groups is added in a molecule such as hydroxyalkyl (meth) acrylate, and the terminal is added. (Meta) Acryloylated carboxyl group-containing photosensitive urethane resin.

(10) During the synthesis of the resin of (8) or (9) above, one isocyanate group and one or more (meth) acryloyl groups in the molecule, such as an isophorone diisocyanate and pentaerythritol triacrylate homomolar reaction product. Carboxyl group-containing photosensitive urethane resin that has been acrylicized at the end (meth) by adding a compound having.

(11) 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.

(12) Carboxyl in which (meth) acrylic acid is reacted with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl group of a bifunctional (solid) epoxy resin with epichlorohydrin, and a dibasic acid anhydride is added to the generated hydroxyl group. Group-containing photosensitive resin.

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

(14) (Meta) acrylic acid is added to a reaction product such as a polyalcohol resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule, that is, a polyphenol compound, with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing photosensitive resin obtained by reacting an unsaturated group-containing monocarboxylic acid such as the above with a reaction product obtained by further reacting a polybasic acid anhydride.

(15) 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 or propylene carbonate. A carboxyl group-containing photosensitive resin obtained by reacting a reaction product with a polybasic acid anhydride.

(16) Carboxyl group-containing photosensitive obtained by further adding a compound having one epoxy group and one or more (meth) acryloyl groups in one molecule to the above-mentioned resins (3), (7) to (15). Sex resin.

As these (B) carboxyl group-containing resins, those other than those described in (7) to (16) can be used, and one type may be used alone or a plurality of types may be mixed and used. .. Among the carboxyl group-containing resins, a resin having an aromatic ring is particularly preferable because it has excellent resolution.

Since the above-mentioned (B) carboxyl group-containing resin has a large number of carboxyl groups in the side chain of the backbone polymer regardless of whether it is photosensitive or non-photosensitive, it can be developed with a dilute alkaline aqueous solution.

Further, the acid value of the (B) carboxyl group-containing resin is appropriately in the range of 40 to 200 mgKOH / g, and more preferably in the range of 45 to 120 mgKOH / g. When the acid value of the carboxyl group-containing resin is within such a range, alkaline development is facilitated, dissolution of the exposed portion by the developer is suppressed, the line is not thinned more than necessary, and there is no dissolution peeling by the developer. Normal pattern drawing is possible.

The mass average molecular weight of the above-mentioned (B) carboxyl group-containing resin varies depending on the resin skeleton, but is generally preferably in the range of 2,000 to 150,000, more preferably 5,000 to 100,000. .. When the mass average molecular weight is within such a range, the tack-free performance is excellent, the moisture resistance of the coating film after exposure is good, and the resolution, developability, and storage stability are excellent.

The content of the (B) carboxyl group-containing resin is preferably in the range of 30 to 70% by mass, preferably 45 to 60% by mass in the main agent composition. When the blending amount of the carboxyl group-containing resin is within such a range, the strength of the cured coating film does not decrease, and the thickening and the decrease in workability do not occur.

[Acryloyl group-containing resin]
The present invention may further contain an acryloyl group-containing resin as the acrylate-based resin. The acryloyl group-containing resin of the present invention contains two or more phenolic hydroxyl groups in a molecule containing the structure of the following general formula (I), which is obtained by a condensation reaction between a polymethylol form of bisphenol A or bisphenol F and phenols. By using the phenol compound (a) having a specific structure, that is, a novolak-type phenol resin having a specific structure, the drying property of the ink composition before curing is improved, and a part or all of the phenolic hydroxyl groups of this resin is made into alcohol. Flexibility is imparted by conversion to an oxyalkyl group having a sex hydroxyl group, and α, β is added to the terminal hydroxyl group of the resulting oxyalkyl group by adding acrylic acid and / or methacrylic acid (c). -Since an ethylenically unsaturated group is added to the end of the side chain, reactivity is improved, heat resistance and toughness are balanced at a high level, excellent in hardness and flexibility, and water resistance. , A cured product having excellent chemical resistance and the like can be obtained.

(In the formula, R ₁ is -C (CH ₃ ) _2- or -CH _2- , R ₂ is a hydrocarbon group having 1 to 11 carbon atoms, a is an integer of 0 to 3, and n is 1 to 1. It represents an integer of 2, and m represents an integer of 1 to 10.)
The phenol compound (a) having two or more phenolic hydroxyl groups in the molecule containing the structure of the general formula (I) causes a condensation reaction between the polymethylol form of bisphenol A or bisphenol F and the phenols in the presence of an acidic catalyst. Obtained by that.
As the phenols, phenols, various cresols, alkylphenols such as various xylenols, and naphthols can be used, and o-cresol and 2,6-xylenol are preferably used. Further, these may be mixed and used.
The addition ratio of the compound (b) having a cyclic ether group such as an alkylene oxide or a cyclic carbonate to the phenol compound (a) is 0.5 mol, preferably 0.8 per 1 equivalent of the phenolic hydroxyl group of the phenol compound (a). ~ 3.0 mol is good. When the amount is in the range of 0.5 to 5.0 mol, the obtained acryloyl group-containing photosensitive resin is excellent in photocurability and drying property.
The content of such an acryloyl group-containing resin is preferably in the range of 5 to 20% by mass, preferably 8 to 15% by mass in the main agent composition.

[(C) Photopolymerization Initiator]
Examples of the (C) photopolymerization initiator include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphinoxide, and bis-. (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphinoxide, bis- (2,6-dimethoxybenzoyl) phenylphosphin oxide, Bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, Bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphinoxide, Bis- (2,4) , 6-trimethylbenzoyl) -bisacylphosphinoxides such as phenylphosphinoxide; 2,6-dimethoxybenzoyldiphenylphosphinoxide, 2,6-dichlorobenzoyldiphenylphosphinoxide, 2,4,6-trimethylbenzoyl Monoacylphosphine oxides such as phenylphosphinic acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 1-hydroxy -Cyclohexylphenyl ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy-1-{4- [4- (2) -Hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propane-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one and other hydroxyacetophenones; benzoin, benzyl , Benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether and other benzoins; benzoin alkyl ethers; benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'- Benzophenones such as dichlorobenzophenone and 4,4'-bisdiethylaminobenzophenone; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1- Dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanol, 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. Acetphenones; thioxanthones such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone. , 2-Methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone and other anthraquinones; acetphenone dimethyl ketal, benzyl dimethyl ketal and other ketals; ethyl Ethyl benzoates such as -4-dimethylaminobenzoate, 2- (dimethylamino) ethylbenzoate, p-dimethylbenzoic acid ethyl ester; 1,2-octanedione, 1- [4- (phenylthio)-, 2-( O-benzoyloxime)], etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime) and other oxime esters; (Η5-2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) phenyl) titanium, bis (cyclopentadienyl) -bis [2, 6-Difluoro-3- (2- (1-pill-1-yl) ethyl) phenyl] Titanosen such as titanium; phenyldisulfide 2-nitrofluorene, butyloin, anisoin ethyl ether, azobisisobutyronitrile, tetra Methylthium disulfide and the like can be mentioned. As the photopolymerization initiator, one type may be used alone, or two or more types may be used in combination.

The content of the (C) photopolymerization initiator is preferably 5 to 15 parts by mass with respect to 100 parts by mass of the (B) carboxyl group-containing resin. When it is 5 parts by mass or more, the surface curability is good, and when it is 15 parts by mass or less, halation is less likely to occur and good resolution can be obtained.

[(D) Photosensitive Monomer]
The photocurable thermosetting resin composition capable of forming the cured product of the present invention may contain a known and commonly used photosensitive monomer. (D) The photosensitive monomer can be, for example, a compound having one or more ethylenically unsaturated groups in the molecule. Such (D) photosensitive monomer assists photocuring of (B) carboxyl group-containing resin by irradiation with active energy rays (when ethylenically unsaturated group is contained), and is a photocurable thermosetting resin. It cures the composition.

The (D) photosensitive monomer preferably used in the present invention is, for example, methyl α- (allyloxymethyl) acrylate, or 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate. Diacrylate of diols such as 1,9-nonanediol diacrylate and 1,10-decanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, Dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, neopentyl glycol diacrylate, neopentyl glycol diacrylate, caprolactone of diol obtained by adding at least one of ethylene oxide and propylene oxide to neopentyl glycol. Glycol diacrylates such as modified hydroxypivalate neopentyl glycol diacrylates, EO adduct diacrylates of bisphenol A, PO adduct diacrylates of bisphenol A, tricyclodecanedimethanol diacrylates, hydrogenated dicyclopentadienyldi. Bifunctional (meth) acrylates such as acrylates, diacrylates having a cyclic structure such as cyclohexyl diacrylates, or corresponding methacrylate monomers, pentaerythritol triacrylates, trimethylolpropane triacrylates, trimethylolmethanetriacrylates, and ethylene oxide modifications. Trimethylol Propane Triacrylate, Proteyl Oxide Modified Trimethylol Propane Triacrylate, Epichlorohydrin Modified Trimethylol Propane Triacrylate, Pentaerythritol Tetraacrylate, Pentaerythritol Tetramethacrylate, Tetramethylol Methantetraacrylate, Ethylene Oxide Modified Phosphoric Acid Triacrylate, Epichlorohydrin Modified glycerol Tri Polyfunctional acrylates such as acrylates, dipentaerythritol hexaacrylates, dipentaerythritol monohydroxypentaacrylates, or modified silsesquioxane thereof, or metaacrylate monomers corresponding thereto, trifunctional methacrylates, ε- Acrylate Examples thereof include polyfunctional (meth) acrylates such as Kuton-modified tris (acroxyethyl) isocyanurate, or combinations of two or more thereof.

The content of such (D) photosensitive monomer is preferably in the range of 10 to 27 parts by mass, preferably 15 to 20 parts by mass with respect to the total 100 parts by mass (solid content) of the (B) carboxyl group-containing resin. The range is more preferred.
(D) When the content of the photosensitive monomer is within such a range, the photocurable thermosetting resin composition has sufficient photocurability, better patterning during development, and tackiness (d). The dryness to the touch) is also good.

[(E) Silica]
In the present invention, (E) silica is preferably contained as a filler in the main agent composition in the case of a two-component system. (E) Silica is preferably used in the present invention because it is excellent in its low hygroscopicity and low volume expansion.
(E) The silica may be either amorphous or crystalline, or a mixture thereof, but amorphous silica is preferable.
In the present invention, (E) silica is usually preferably used as a slurry dispersed in a solvent from the viewpoint of ease of handling such as maintaining the degree of dispersion.

[(F) Barium sulfate]
In the present invention, (F) barium sulfate also acts as a filler like the above-mentioned (E) silica, but it is preferable that it is contained separately from (E) silica in the curing agent composition instead of the main agent composition. .. This is because the appearance of the composition coating film obtained from the mixed composition such as the formation of Benard cells may be impaired. In the present invention, from the viewpoint of ease of handling such as maintaining the degree of dispersion, (F) barium sulfate is usually preferably used as a slurry dispersed in a solvent.

The silica (E) and barium (F) sulfate are preferably surface-treated, and it is more preferable that the surfaces thereof are surface-treated so that a curable reactive group can be introduced.
Here, the curable reactive group refers to a group that undergoes a curing reaction with (A) an epoxy resin or the like or (B) a carboxyl group-containing resin, and may be a photocurable reactive group or a thermosetting reactive group. Examples of the photocurable reactive group include a methacryl group, an acrylic group, a vinyl group, a styryl group and the like, and examples of the thermosetting reactive group include an epoxy group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, an imino group and an oxetanyl. Examples thereof include a group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, an oxazoline group and the like.
The method for introducing the curable reactive group on the surfaces of (E) silica and (F) barium sulfate is not particularly limited, and the curable reactive group may be introduced by using a known and commonly used method, and a surface treatment agent having a curable reactive group, for example. , The surface of the inorganic filler may be treated with a coupling agent or the like having a curable reactive group as an organic group. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent and the like can be used. Examples of the surface-treated inorganic filler having no curable reactive group include silica-alumina surface treatment, titanate-based coupling agent treatment, aluminate-based coupling agent treatment, and organically treated inorganic filler. Can be mentioned.

(E) The average particle size (D50) of the silica slurry is 2000 nm or less, more preferably 1200 nm or less. The lower limit thereof is preferably 0.1 nm or more as the average particle diameter (D50).
The average particle size (D50) of the barium sulfate slurry (F) is 1000 nm or less, more preferably 500 nm or less. The lower limit thereof is preferably 0.1 nm or more as the average particle diameter (D50).
The smaller the average particle size of (E) silica and (F) barium sulfate, the more diffused reflection during light irradiation can be suppressed and the fine processing of the cured product pattern can be facilitated.
The average particle size (D50) can be determined by a laser diffraction type particle size distribution measuring device and a measuring device by a dynamic light scattering method. Examples of the measuring device by the laser diffraction method include Microtrac MT3300EXII manufactured by Microtrac Bell, and examples of the measuring device by the dynamic light scattering method include Nanotrac Wave II UT151 manufactured by Microtrac Bell.

The contents of (E) silica and (F) barium sulfate are of the present invention from the viewpoint that they can impart the properties necessary for a solder resist such as suppression of heat fog, high resolution, and good crack resistance. It is more preferably 15% by mass to 30% by mass, respectively, with respect to the total amount of the non-volatile components of the photocurable thermosetting resin composition.

[Organic solvent]
In the present invention, an organic solvent is used for preparing a photocurable thermosetting resin composition and adjusting its viscosity, or for preparing a slurry of (E) silica or a slurry of (F) barium sulfate. May be.
Examples of such organic solvents are ketones such as methyl ethyl ketone, cyclohexanone; aromatic hydrocarbons such as toluene, xylene, tetramethyl benzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, etc. Glycol ethers such as propylene glycol monomethyl ether, dipropylene glycol monomethyl ether (DPM), dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, Esters such as butyl carbitol 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. Can be used.
These organic solvents can be used alone or in combination of two or more.
The content of the organic solvent is preferably in the range of 5% to 25% by mass with respect to the main composition of the photocurable thermosetting resin composition of the present invention. The content of this organic solvent also includes the organic solvent in the slurry of (E) silica.
The curing agent composition is an organic solvent capable of dissolving (C) the photopolymerization initiator to be blended in the composition, and is 3 parts by mass or more with respect to 1 part by mass of (C) the photopolymerization initiator. It is preferable to contain the organic solvent of. (C) The organic solvent capable of dissolving the photopolymerization initiator is "○: No crystals of the photopolymerization initiator were visually observed" as a result of the "confirmation test of solubility of the photopolymerization initiator" described later. (See Table 1) means an organic solvent. By selecting and using such an organic solvent, crystals of the (C) photopolymerization initiator are not formed, so that the generation of coarse particles can be suppressed.
In the organic solvents shown in Table 1, PMA and CA are excellent in coatability of the photocurable thermosetting resin composition after mixing and dryness to the touch after coating. Therefore, PMA alone or a mixture of PMA and CA is used. It is more preferable to use a solvent.
The upper limit of the content of the organic solvent can be appropriately adjusted depending on the maximum dissolution amount of the (C) photopolymerization initiator (see Table 2 below). Similarly, photopolymerization initiators other than Omnirad TPO H shown in Tables 1-2 to 1-5 can be appropriately adjusted.

[Other ingredients]
In the photocurable thermosetting resin composition of the present invention, it is of course possible to add additional additives as other components as necessary within the range not deviating from the object of the present invention.
Such components include, for example, colorants such as pigments and dyes, thermal polymerization inhibitors, ultraviolet absorbers, plasticizers, flame retardants, antistatic agents, antiaging agents, antibacterial / antifungal agents, leveling agents, thickening agents. Agents, adhesion-imparting agents, thixo-imparting agents, photoinitiator aids, sensitizers, photobase generators, thermoplastic resins, elastomers, organic fillers, fillers other than silica and barium sulfate, mold release agents, surface treatment agents , Dispersants, dispersion aids, surface modifiers, stabilizers, phosphors, cellulose resins and the like.

The main ingredient composition and the curing agent composition of the photocurable thermosetting resin composition of the present invention can be prepared by mixing and dispersing each of these components in a predetermined amount, for example, with a three-roll mill or the like. ..

[Dry film]
The photocurable thermosetting resin composition of the present invention is preferably used as a dry film.
The dry film of the present invention has a resin layer obtained by applying and drying the photocurable thermosetting resin composition of the present invention on a carrier film. When forming a dry film, first, in the case of a two-component system, the main agent composition and the curing agent composition are mixed well with each other to obtain the photocurable thermosetting resin composition of the present invention. , As it is, or diluted with an organic solvent as needed to adjust the viscosity to an appropriate level, then a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer coater, gravure coater, spray. Apply to a uniform thickness on the carrier film with a coater or the like. Then, the applied composition is usually dried at a temperature of 50 to 130 ° C. for 1 to 30 minutes to form a resin layer. The coating film thickness is not particularly limited, but is generally selected as appropriate in the range of 10 to 150 μm, preferably 20 to 60 μm after drying.

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

After forming the resin layer made of the photocurable thermosetting resin composition of the present invention on the carrier film, for the purpose of preventing dust from adhering to the surface of the resin layer, further, on the surface of the resin layer. It is preferable to laminate a peelable cover film. 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. The cover film may be one having a force smaller than the adhesive force between the resin layer and the carrier film when the cover film is peeled off.

In the present invention, the photocurable thermosetting resin composition of the present invention is applied onto the cover film and dried to form a resin layer, and a carrier film is laminated on the surface thereof. May be good. That is, as the film to which the curable 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.

Here, the photocurable thermosetting resin composition of the present invention is adjusted to a viscosity suitable for the coating method using, for example, an organic solvent, and is subjected to a dip coating method, a flow coating method, and a roll coating method on a substrate. After applying by a method such as a bar coater method, a screen printing method, a curtain coating method, etc., the organic solvent contained in the composition is volatilized and dried (temporarily dried) at a temperature of about 60 to 100 ° C. to make it tack-free. It is also possible to form a resin layer. Further, in the case of a dry film in which the above composition is applied onto a carrier film or a cover film, dried and wound as a film, the layer of the composition of the present invention is placed on the substrate so as to be in contact with the substrate by a laminator or the like. A resin layer can be formed by peeling off the carrier film after the resin layer is attached to the film.

The base material includes a printed wiring board and a flexible printed wiring board whose circuit is previously formed of copper or the like, 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. Examples thereof include a plate, a metal substrate, a polyimide film, a PET film, a polyethylene naphthalate (PEN) film, a glass substrate, a ceramic substrate, a wafer plate, and the like.

[Cursed product]
In order to form a cured product using the photocurable thermosetting resin composition of the present invention, the composition is applied onto a substrate, and the resin layer obtained after volatilizing and drying the solvent is exposed (light). By performing irradiation), the exposed portion (the portion irradiated with light) is cured. Specifically, the unexposed portion is exposed to an alkaline aqueous solution (for example, by selectively exposing with active energy rays through a photomask in which a pattern is formed by a contact method or a non-contact method, or by directly exposing the pattern with a laser direct exposure machine. , 0.3 to 3% by mass of sodium carbonate aqueous solution) to form a resist pattern. Further, by heating to a temperature of about 100 to 180 ° C. and thermosetting (post-curing), a cured film (cured product) having excellent various properties such as heat resistance, chemical resistance, hygroscopicity, adhesion, and electrical characteristics is obtained. ) Can be formed.

For volatile drying or heat curing when forming the cured product, for example, a hot air circulation type drying furnace, an IR furnace, a hot plate, a convection oven, etc. It can be performed by using a method of bringing hot air into countercurrent contact and a method of blowing hot air onto a support from a nozzle).

Further, as the exposure machine used for the above-mentioned active energy ray irradiation, if it is 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. Often, a direct drawing device (eg, a laser direct imaging device that draws an image directly with a laser from 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 410 nm. The exposure amount for image formation varies depending on the film thickness and the like, but is generally 20 to 1000 mJ / cm2, preferably 20 to 800 mJ / cm2.

The development method can be a dipping method, a shower method, a spray method, a brush method, or the like, and the developers include potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, and the like. Alkaline aqueous solutions such as ammonia and amines can be used.

[Electronic components]
The present invention can also provide an electronic component having the above-mentioned cured product.
By using the photocurable thermosetting resin composition of the present invention, electronic components having high quality, durability and reliability are provided.
In the present invention, the electronic component means a component used in an electronic circuit, and includes active components such as printed wiring boards, transistors, light emitting diodes, and laser diodes, as well as passive components such as resistors, capacitors, inductors, and connectors. Is done.

Hereinafter, one aspect of the present invention will be specifically shown by way of examples, but of course, it is not an object to limit the scope of the invention according to the present invention.
Unless otherwise specified, the "parts" and "%" shown are based on mass.

Test example 1. Confirmation of Solubility of Photopolymerization Initiator Prior to the experiment on each property of the photocurable thermosetting resin composition of the present invention, in order to select a suitable organic solvent for the photopolymerization initiator, a preliminary preparation. A test for confirming the solubility of the five photopolymerization initiators in an organic solvent was conducted as follows.
First, a test was conducted to confirm the general solubility of the five photopolymerization initiators in various organic solvents, and the subsequent addition amount was used as a guideline (Tables 1-1 to 1-5).
Next, a predetermined amount of each of the four solvents was added to the prepared vial, and a photopolymerization initiator (Omnirad TPO H) was further added to the vial, and then the vial was shaken by hand to stir for 5 minutes. It was left still. Then, the presence or absence of crystals of the photopolymerization initiator was visually confirmed, and if no crystals were confirmed, the photopolymerization initiator was further added, the mixture was stirred by hand, and the mixture was allowed to stand for 5 minutes. This operation is repeated until crystals are confirmed, and when crystals are finally confirmed after being left for 5 minutes, the addition of the photopolymerization initiator is terminated, and the amount added before the crystals are confirmed is set to light. The maximum amount of the polymerization initiator Omnirad TPO H was used (Table 2).
The evaluation criteria are as follows.
〇: No crystals of the photopolymerization initiator were visually observed. ×: Crystals of the photopolymerization initiator were visually observed (not dissolved over time).
The results are shown in Tables 1-1-5 and Table 2 below.

* The photopolymerization initiators and organic solvents shown in Tables 1-1 to 1-5 and Table 2 are as follows.
-TPO: Acylphosphine oxide-based photopolymerization initiator (Omnirad TPO H manufactured by IGM Resins B.V.) (2,4,6-trimethylbenzoyl-diphenyl-phosphinoxide)
907: α-aminoacetophenone-based photopolymerization initiator (Omnirad 907 manufactured by IGM Resins) (2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one)
379: Alkylphenone-based photopolymerization initiator (Omnirad 379EG manufactured by IGM Resins B.V.) (2- (dimethylamino) -2- (4-methylbenzyl) -1- (4-morpholinophenyl) butane-1 on)
784: Titanocene-based photopolymerization initiator (JMT-784 manufactured by Yueyang Jinmao Technology Co., Ltd.)
OXE02: Oxime Ester Photopolymerization Initiator (Irgacure OXE02 (Etanon, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl] -1- (o-) manufactured by BASF Japan Ltd.) Acetyloxime)
・ PMA (Propylene Glycol Monomethyl Ether Acetate)
・ CA (carbitol acetate)
・ GBL (γ-butyrolactone)
・ MEK (Methyl Ethyl Ketone)

[Synthesis example 1. Synthesis of Carboxyl Group-Containing Resin (B-1)]
A flask equipped with a cooling tube and a stirrer was charged with 456 parts of bisphenol A, 228 parts of water, and 649 parts of 37% formalin, kept at a temperature of 40 ° C. or lower, and 228 parts of a 25% sodium hydroxide aqueous solution was added. The reaction was carried out at ° C. for 10 hours. After completion of the reaction, the mixture was cooled to 40 ° C. and neutralized to pH 4 with a 37.5% aqueous phosphoric acid solution while maintaining 40 ° C. or lower. After that, it was allowed to stand and the aqueous layer was separated. After separation, 300 parts of methyl isobutyl ketone was added and uniformly dissolved, followed by washing with 500 parts of distilled water three times, and the water, solvent and the like were removed under reduced pressure at a temperature of 50 ° C. or lower. The obtained trimethylol compound was dissolved in 550 parts of methanol to obtain 1230 parts of a methanol solution of the trimethylol compound. When a part of the obtained methanol solution of the polypeptideol compound was dried in a vacuum dryer at room temperature, the solid content was 55.2%.

500 parts of a methanol solution of the obtained trimethylol compound and 440 parts of 2,6-xylenol were charged and uniformly dissolved at 50 ° C. After uniform dissolution, methanol was removed under reduced pressure at a temperature of 50 ° C. or lower. Then, 8 parts of oxalic acid was added, and the reaction was carried out at 100 ° C. for 10 hours. After completion of the reaction, the distillate was removed at 180 ° C. under a reduced pressure of 50 mmHg to obtain 550 parts of novolak resin A. Further, in an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device, 130 parts of the above novolak resin A, 2.6 parts of a 50% sodium hydroxide aqueous solution, and toluene / methyl isobutyl ketone (mass ratio). = 2/1) 100 parts were charged, the inside of the system was replaced with nitrogen while stirring, then the temperature was raised by heating, and 45 parts of ethylene oxide was gradually introduced at 150 ° C. and 8 kg / cm ² to react. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg / cm ² , and then cooled to room temperature. 3.3 parts of a 36% aqueous hydrochloric acid solution was added to and mixed with this reaction solution to neutralize sodium hydroxide. The product of this neutralization reaction was diluted with toluene, washed with water three times, and desolvated with an evaporator to give a hydroxyl value of 175 g / eq. An ethylene oxide adduct of novolak resin A was obtained. This had an average of 1 mol of ethylene oxide added per equivalent amount of phenolic hydroxyl group.

175 parts of the ethylene oxide adduct of the novolak resin A thus obtained, 50 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.1 part of hydroquinone monomethyl ether, and 130 parts of toluene were mixed with a stirrer, a thermometer, and air. It was charged into a reactor equipped with a blow tube, stirred while blowing air, heated to 115 ° C., and the water produced by the reaction was distilled off as an azeotropic mixture with toluene and reacted for another 4 hours. Cooled to room temperature. The obtained reaction solution was washed with water using a 5% NaCl aqueous solution, toluene was removed by distillation under reduced pressure, and then diethylene glycol monoethyl ether acetate was added to obtain an acrylate resin solution having a solid content of 68%.

Next, 312 parts of the obtained acrylate resin solution, 0.1 part of hydroquinone monomethyl ether, and 0.3 part of triphenylphosphine were charged in a four-necked flask equipped with a stirrer and a reflux condenser, and the mixture was charged at 110 ° C. To, 45 parts of tetrahydrophthalic anhydride was added, and the mixture was reacted for 4 hours, cooled, and then taken out. The carboxyl group-containing resin (B-1) thus obtained had a non-volatile content of 72% and a solid content acid value of 65 mgKOH / g.

[Synthesis example 2. Synthesis of Carboxyl Group-Containing Resin (B-2)]
In an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device, cresol novolak resin (Shonol CRG-951 manufactured by Aika Industries, OH equivalent: 119.4) 119.4 parts, potassium hydroxide 1. 19 parts and 119.4 parts of toluene were introduced, the inside of the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 parts of propylene oxyside was gradually added dropwise and reacted at 125 to 132 ° C. and 0 to 4.8 kg / cm2 for 16 hours. Then, the mixture was cooled to room temperature, 1.56 parts of 89% phosphoric acid was added to and mixed with this reaction solution to neutralize potassium hydroxide, the non-volatile 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 at 9 g / eq.) Was obtained. This had an average of 1.08 mol of propylene oxide added per equivalent amount of phenolic hydroxyl group.

293.0 parts of propylene oxide reaction solution of the obtained novolak type cresol resin, 43.2 parts of acrylic acid, 11.53 parts of methanesulfonic acid, 0.18 parts of methylhydroquinone and 252.9 parts of toluene were added to the stirrer and temperature. It was introduced into a reactor equipped with a meter and an air blow tube, and 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 of water was distilled off as an azeotropic mixture with toluene. Then, the mixture was cooled to room temperature, the obtained 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 novolak type acrylate resin solution.

Next, 332.5 parts of the obtained novolak-type acrylate resin solution and 1.22 parts of triphenylphosphine were introduced into a reactor equipped with a stirrer, a thermometer and an air blow tube, and air was introduced at a rate of 10 ml / min. With stirring, 60.8 parts of tetrahydrophthalic anhydride was gradually added, reacted at 95 to 101 ° C. for 6 hours, cooled, and then taken out. In this way, a carboxyl group-containing resin (B-2) having a solid content of 65% and an acid value of 87.7 mgKOH / g as a solid content was obtained.

[Synthesis example 3. Synthesis of acryloyl group-containing resin]
A flask equipped with a cooling tube and a stirrer was charged with 456 parts of bisphenol A, 228 parts of water, and 649 parts of 37% formalin, kept at a temperature of 40 ° C. or lower, and 228 parts of a 25% sodium hydroxide aqueous solution was added. The reaction was carried out at ° C. for 10 hours. After completion of the reaction, the mixture was cooled to 40 ° C. and neutralized to pH 4 with a 37.5% aqueous phosphoric acid solution while maintaining 40 ° C. or lower. After that, it was left to stand and the water layer was separated. After separation, 300 parts of methyl isobutyl ketone was added and uniformly dissolved, followed by washing with 500 parts of distilled water three times, and the water, solvent and the like were removed under reduced pressure at a temperature of 50 ° C. or lower. The obtained trimethylol compound was dissolved in 550 parts of methanol to obtain 1230 parts of a methanol solution of the trimethylol compound. When a part of the obtained dimethylol compound methanol solution was dried in a vacuum dryer at room temperature, the solid content was 55.2%.

500 parts of a methanol solution of the obtained trimethylol compound and 440 parts of 2,6-xylenol were charged and uniformly dissolved at 50 ° C. After uniform dissolution, methanol was removed under reduced pressure at a temperature of 50 ° C. or lower. Then, 8 parts of oxalic acid was added, and the reaction was carried out at 100 ° C. for 10 hours. After completion of the reaction, the distillate was removed at 180 ° C. under a reduced pressure of 50 mmHg to obtain 550 parts of novolak resin A. Further, in an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device, 130 parts of the above novolak resin A, 2.6 parts of a 50% sodium hydroxide aqueous solution, and toluene / methyl isobutyl ketone (mass ratio). = 2/1) 100 parts were charged, the inside of the system was replaced with nitrogen while stirring, then the temperature was raised by heating, and 45 parts of ethylene oxide was gradually introduced at 150 ° C. and 8 kg / cm ² to react. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg / cm ² , and then cooled to room temperature. 3.3 parts of a 36% aqueous hydrochloric acid solution was added to and mixed with this reaction solution to neutralize sodium hydroxide. The product of this neutralization reaction was diluted with toluene, washed with water three times, and desolvated with an evaporator to give a hydroxyl value of 175 g / eq. An ethylene oxide adduct of novolak resin A was obtained. This had an average of 1 mol of ethylene oxide added per equivalent amount of phenolic hydroxyl group.

175 parts of the ethylene oxide adduct of the novolak resin A thus obtained, 75 parts of methacrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.1 part of hydroquinone monomethyl ether, and 130 parts of toluene were mixed with a stirrer, a thermometer, and air. It was charged into a reactor equipped with a blow tube, stirred while blowing air, heated to 115 ° C., and the water produced by the reaction was distilled off as an azeotropic mixture with toluene and reacted for another 4 hours. Cooled to room temperature. The obtained reaction solution was washed with 5% NaCl aqueous solution to remove toluene by distillation under reduced pressure, and then diethylene glycol monoethyl ether acetate was added to obtain an acryloyl group-containing resin solution having a solid content of 68%.

(E) Preparation of silica slurry 700 g of spherical silica (SO-E2 manufactured by Admatech), 295 g of propylene glycol monomethyl ether acetate (PMA) as a solvent, and 5 g of a wet dispersant are mixed and stirred, and 0.5 μm zirconia beads are mixed and stirred with a bead mill. Was used for dispersion processing. This was repeated 3 times and filtered through a 3 μm filter to prepare an (E) silica slurry. The average particle size (D50) of the obtained silica slurry was 1200 nm or less.

(F) Preparation of barium sulfate slurry 700 g of barium sulfate (B-30 manufactured by Sakai Chemical Industry Co., Ltd.), 295 g of diethylene glycol monoethyl ether acetate (carbitol acetate) as a solvent, and 5 g of a wet dispersant are mixed and stirred, and a bead mill is used in the same manner as above. The dispersion processing was performed at. This was repeated 3 times to prepare a (F) barium sulfate slurry filtered with a 3 μm filter. The average particle size (D50) of the obtained barium sulfate slurry was 500 nm or less.

[Examples 1 to 5 and Comparative Examples 1 to 3]
Each component as shown in Tables 3 and 4 below was premixed with a stirrer at each compounding amount, kneaded with a three-roll mill, and the photocurability of Examples 1 to 5 and Comparative Examples 1 to 3. A thermosetting resin composition (a two-component system consisting of a main agent composition and a curing agent composition) was prepared.

^{* 1} Follow Synthesis Example 1
^{* 2} Follow Synthesis Example 2
^{* 3} Follow Synthesis Example 3
^{* 4} C. I. Pigment red 149
^{* 5} C. I. Pigment yello 147
^{* 6} Copper Phthalocyanine Blue:
^{* 7} Carbon black: MA-100 (Mitsubishi Chemical Corporation)
^{* 8} Melamine
^{* 9} BYK-350 (manufactured by Bickemi Japan)
^{* 10} DPHA: Dipentaerythritol hexaacrylate (six-functional acrylic monomer, manufactured by Nippon Kayaku Co., Ltd.)
^{* 11} Laromar LR8863: EO-modified trimethylolpropane triacrylate (manufactured by BASF Japan Ltd.)
^{* 12} (E) Silica slurry
^{* 13} PMA (Propylene Glycol Monomethyl Ether Acetate)
^{* 14} (F) Barium sulfate slurry
^{* 15} CA (carbitol acetate)
^{* 16} Omnirad TPO H: Acylphosphinoxide-based photopolymerization initiator (manufactured by IGM Resins B.V.)
^{* 17} JMT784: Titanocene-based photopolymerization initiator (manufactured by Yueyang Jinmao Yasushi Technology Co., Ltd.)
^{* 18} Kinopower QS-30: Naphthoquinone-based polymerization inhibitor (manufactured by Kawasaki Kasei Chemicals, Inc.)
^{* 19} PMA (Propylene Glycol Monomethyl Ether Acetate)
^{* 20} GBL (γ-butyrolactone)
^{* 21} MEK (Methyl Ethyl Ketone)
^{* 22} Dicyclopentadiene type epoxy resin (HP-7200L; manufactured by DIC Corporation)
^{* 23} BisA type epoxy resin (jER834; manufactured by Mitsubishi Chemical Corporation)
^{* 24} Biphenyl type epoxy resin
^{* 25} Novolac epoxy resin

The following tests were carried out on the obtained main agent compositions, curing agent compositions and photocurable thermosetting resin compositions obtained by mixing them in Examples 1 to 5 and Comparative Examples 1 to 3. ..

<Dispersity (initial), initial viscosity>
The main agent composition, the curing agent composition, and the photocurable thermosetting resin composition obtained by thoroughly mixing the main agent composition and the curing agent composition of Examples 1 to 5 and Comparative Examples 1 to 3, respectively. The viscosity was measured using a cone plate type viscometer (model number: TVE-33H, manufactured by Tokyo Keiki Co., Ltd.) at a measurement temperature of 25 ° C. and a cone rotation speed of 5 rpm / min, and the values were taken as the initial viscosities. The degree of dispersion was measured by particle size measurement using a grind meter (manufactured by Yasuda Seiki Seisakusho), and the value was taken as the degree of dispersion (initial).
The results are summarized in Table 5 below.

<Dispersity (time)>
The main agent composition and the curing agent composition of Examples 1 to 5 and Comparative Examples 1 to 3 were prepared at 20 ° C. and 5 ° C., 5 days and 10 days after preparation. The degree of dispersion after 15 days, 20 days, and 30 days was measured by particle size measurement using a grind meter (manufactured by Yasuda Seiki Seisakusho), and the value was taken as the degree of dispersion (time).
The evaluation criteria are as follows.
<10 μm: 〇 <12.5 μm: △
<20 μm: ×
The results are summarized in Table 6 below.

<Appearance of composition>
5 days, 10 days, 15 days, 20 days and 30 days after preparation of the main agent composition and the curing agent composition of Examples 1 to 5 and Comparative Examples 1 to 3 when stored at 20 ° C. The surface of each composition in the above was visually confirmed.
The evaluation criteria are as follows.
No surface separation: ○
With surface separation: ×
The results are summarized in Table 7 below.

<Appearance of dry film>
The main agent composition and the curing agent composition of Examples 1 to 5 and Comparative Examples 1 to 3 were stored at 20 ° C., and those after 5 days, 10 days, 15 days, 20 days and 30 days were mixed, respectively. A diluting solvent was added to the obtained photocurable thermosetting resin composition to adjust the viscosity to 4d · Ps. Next, the diluted photocurable thermosetting resin composition was applied to a PET film using an applicator so that the film thickness after drying was 15 μm and 30 μm, respectively, and dried in a hot air circulation drying oven for 30 minutes. rice field. Then, the surface (30 cm × 30 cm) of the obtained coating film was observed with an optical microscope 20 times, and the number of repellents and pinholes was confirmed.
The evaluation criteria are as follows.
0: ○
1 or more and 5 or less: △
More than 5 and less than 10: ×
The results are summarized in Table 8 below.

<Electrical characteristics>
From the photocurable thermosetting resin composition obtained by mixing the main agent composition and the curing agent composition of Examples 1 to 5 and Comparative Examples 1 to 3, the line / space = 20/20 μm instead of the copper foil substrate. Dry films were obtained using comb-shaped electrode patterns. The obtained dry film was vacuum-heated and laminated, a bias voltage of DC10 V was applied, and the time until the insulation resistance value became 10 4 Ω or less at 130 ° C./85% was measured. The average time using 5 pieces of measurement was calculated.
The evaluation criteria are as follows.
Connection time 200 hours or more and 250 hours or less: ○
Connection time 150 hours or more and less than 200 hours: ×
The results are summarized in Table 9 below.

From the results shown in the above table, it can be seen that the photocurable thermosetting resin composition of the present invention is excellent in electrical properties. For both the main agent composition and the curing agent composition of the present invention, the particle size measurement result using a grind meter was <10 μm from the initial stage to 30 days after storage, no coarse particles were generated, and the degree of dispersion and storage stability were not generated. It turns out that it is excellent.
Further, regarding the appearance of the composition, it can be seen that there is no problem such as surface separation in both the main agent composition and the curing agent composition until 30 days after storage, and the storage stability is excellent.
Further, the photocurable thermosetting resin composition of the present invention does not generate cissing and pinholes during the formation of a dry film until 30 days after storage, and is also excellent in storage stability in this respect.
On the other hand, the main agent composition of Comparative Example 1 contains (B) a carboxyl group-containing resin and (C) a photopolymerization initiator, and since they are contained together, the detailed mechanism is unknown, but each example. It can be seen that the degree of dispersion (time) and the stability of the appearance of the composition over time are inferior to those of the above. Further, since the curing agent composition of Comparative Example 1 contains (E) silica and (F) barium sulfate, separation of the liquid surface (color floating / color separation), so-called Benard cell, occurs, and the liquid surface of the composition It can be seen that the appearance of the silica is impaired and the stability over time is inferior.
The main agent composition of Comparative Example 2 contains (B) a carboxyl group-containing resin and (C) a photopolymerization initiator, and since they are contained together, the detailed mechanism is unknown, but it is compared with each example. As a result, the degree of dispersion (with time) and the stability of the appearance of the composition with time are inferior, and since (E) silica and (F) barium sulfate are contained, so-called Benard cells are formed, which are dispersed as compared with each example. It can be seen that the degree (time) and the stability of the appearance of the composition over time are inferior.
The main agent composition of Comparative Example 3 does not contain (E) silica, and the curing agent composition does not contain (E) silica and contains only (F) barium sulfate, that is, both components are used in combination in one composition. Not done. Further, since (B) the carboxyl group-containing resin and (C) the photopolymerization initiator are not used in combination in the main composition, there are no problems in the degree of dispersion (time) and the stability of the appearance of the composition over time, but comparison is made. Since (E) silica, which is an essential component, is not contained in either the main agent composition or the curing agent composition of Example 3, repellents and pinholes are generated during the formation of the dry film obtained from the mixture. Therefore, in Comparative Example 3, it is clear that the evaluation of electrical characteristics is inferior, so that evaluation is not performed.
As described above, since there is a problem in the combination of the components of the main agent composition and the curing agent composition of Comparative Examples 1 and 2, poor appearance and coarse particles are generated over time, respectively, and each comparative example is a mixture thereof. It can be seen that the evaluation and electrical characteristics of repellents and the like during formation of the dry film obtained from the photocurable thermosetting resin composition of No. 1 are also clearly inferior to those of the examples.

Claims (8)

1. Photocurable thermosetting containing (A) epoxy resin, (B) carboxyl group-containing resin, (C) photopolymerization initiator, (D) photosensitive monomer, (E) silica, (F) barium sulfate and organic solvent. It is a curable resin composition and is
   In order to obtain the photocurable thermosetting resin composition, the resin composition is composed of at least two liquids.
   The (B) carboxyl group-containing resin, the (D) photosensitive monomer, and the (E) silica are different from the (A) epoxy resin, the (F) barium sulfate, and the (C) photopolymerization initiator. Included in the resin composition of
   The resin composition containing the (C) photopolymerization initiator is characterized by containing an organic solvent capable of dissolving the (C) photopolymerization initiator.
   A photocurable thermosetting resin composition composed of at least a two-component resin composition.
2. The photocurable thermosetting according to claim 1, wherein the (A) epoxy resin contains three types of a semi-solid or solid epoxy resin, a biphenyl type epoxy resin and a novolak type at room temperature. Resin composition.
3. The resin composition containing the epoxy resin (A) has a viscosity of 4 dPa · s or less, and the photocurable thermosetting resin composition obtained by mixing the respective resin compositions is 4 dPa · s. The photocurable thermosetting resin composition according to claim 1 or 2, which has the following viscosity.
4. The resin composition containing the (A) epoxy resin contains the (C) photopolymerization initiator and the organic solvent, and is 3 parts by mass or more with respect to 1 part by mass of the (C) photopolymerization initiator. The photocurable thermosetting resin composition according to any one of claims 1 to 3, which contains an organic solvent.
5. A dry film having a film thickness of 10 μm to 30 μm, which is obtained by applying and drying the photocurable thermosetting resin composition according to any one of claims 1 to 4 on a carrier film.
6. A cured product obtained by curing the photocurable thermosetting resin composition according to any one of claims 1 to 4.
7. A cured product obtained by curing the resin layer of the dry film according to claim 5.
8. An electronic component comprising the cured product according to claim 6 or 7.