TWI825246B - Hardening compositions, dry films, hardened materials and electronic parts - Google Patents

Abstract

The present invention provides curable compositions, dry films, cured products, and electronic parts that contain hydrophilic silica and polysiloxane-based surface conditioners, have good weldability, and eliminate problems of silica aggregation and precipitation. The curable composition of the present invention includes (A) alkali-soluble resin, (B) photopolymerization initiator, (C) epoxy resin, (D) polysiloxy compound, (E) hydrophilic silica, and ( F) Organic thixotropic agent. This eliminates the problem of aggregation and precipitation of hydrophilic silica in the curable composition. When the curable composition is coated on the substrate, the (D) polysiloxane compound maintains the wettability to the substrate. , and at the same time improves the wettability of the flux to the obtained hardened product, so when the hardened product is used as a solder resist, the weldability improvement effect can be obtained.

Description

Hardening compositions, dry films, hardened materials and electronic parts

The present invention relates to curable compositions, dry films, cured materials, and electronic components, and in particular to alkali-developable curable compositions, dry films thereof, cured materials thereof, and electronic components having cured materials thereof.

In the past, from the viewpoint of high precision and high density, solder resists for consumer printed circuit boards or industrial printed wiring boards were used to form images through development after ultraviolet irradiation, using heat and/or light. Among the liquid developing type solder resists that are work-hardened (formally hardened) by irradiation, among the liquid developing type solder resists, due to concerns about environmental issues, the mainstream is the alkali developing type photoresist that uses an alkali aqueous solution as the developer. Flux.

Generally, a solder resist composition is used to form a photo-solder resist on a substrate and is coated on the substrate. In order to improve the wettability of the solder resist composition to the substrate and to improve the leveling (flatness) of the coating film, And add polysiloxane surface conditioner.

After the photo-solder resist is formed on the substrate, the parts are mounted on the substrate by soldering. However, since the wettability of the molten solder to the substrate is low, the solder resist is included in order to improve the wettability (cleaning and anti-oxidation of the soldering surface). The entire surface of the substrate is coated with flux.

Therefore, through examination by the present inventors, it was found that if the solder resist formed on the substrate contains a polysiloxane-based surface conditioner, the flux will not adhere to the substrate and the solderability will be reduced.

On the other hand, it is well known that silicon dioxide as an inorganic filler is added to the solder resist composition in order to enhance the rigidity of the solder resist and suppress the hardening shrinkage of the solder resist composition.

Patent Document 1 discloses, as a comparative example, an alkali-developing photo-curable and thermosetting solder resist composition containing a polysiloxane-based surface conditioner as a solder resist composition of the above-mentioned prior art in its Examples. 2, discloses an alkali-developable photo-curable and thermo-curable solder resist composition containing molten spherical silica without surface modification treatment as an inorganic powder. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2009-194222

[Problem to be solved by the invention]

According to the embodiment of Patent Document 1, the alkali-developing photo-curable and thermosetting solder resist composition containing a polysiloxane-based surface conditioner improves the wettability of the solder resist composition to the substrate, but due to the The solder resist will prevent the flux from sticking, so it will reduce the solderability.

Furthermore, according to the alkali-developable photocurable and thermosetting solder resist composition of Comparative Example 2 of Patent Document 1, the added silicon dioxide has not been subjected to surface modification treatment and is hydrophilic. Therefore, this may occur. There is a risk of aggregation and precipitation problems. For example, the surface must be modified to be hydrophobic to eliminate aggregation and precipitation problems. In addition, since the alkali-developing photocurable and thermosetting solder resist composition of Comparative Example 2 does not add a polysiloxane-based surface conditioner, the wettability of the solder resist composition to the substrate cannot be improved.

The present invention was made in view of the above-mentioned problems, and its object is to provide a curable composition, a dry composition containing hydrophilic silica and a polysiloxane-based surface conditioner, which has good weldability and eliminates the problems of silica aggregation and precipitation. Films, hardened materials and electronic parts. [Means used to solve problems]

In order to achieve the above-mentioned object, the present inventors conducted active examination. As a result, it was unexpectedly found that when polysiloxane, hydrophilic silica and organic thixotrope are formulated, the wettability of the copper-clad substrate and solder resist composition can be maintained, and the problems of aggregation and precipitation of hydrophilic silica can be eliminated. And the problem of flux non-adhesion caused by polysiloxane compounds led to the completion of the present invention.

That is, it is found that the above object of the present invention can be achieved by the following curable composition. The characteristics of the curable composition include: (A) Alkali-soluble resin, (B) Photopolymerization initiator, (C) Epoxy resin, (D)Polysilicone compound, (E) Hydrophilic silica, and (F) Organic thixotropic agent.

In the curable composition of the present invention, it is further preferred that (E) the median diameter D50 of the hydrophilic silica is 0.2 μm or more and 2.0 μm or less.

Furthermore, the preferred amount of (F) organic thixotrope is 0.01 to 15 parts by mass relative to 100 parts by mass of (E) hydrophilic silica, and 2 mass parts to (D) polysiloxy compound. parts, more than 0.05 parts by mass.

Moreover, it is preferable to further contain (G) antioxidant.

In addition, the above object of the present invention can be achieved by a dry film, a cured product and an electronic component. The dry film is characterized by being obtained by coating the curable composition of the present invention on a carrier film and drying it. The characteristics of the cured product are obtained by applying the curable composition of the present invention on a base material and drying the resulting dry coating film, or by coating the aforementioned curable composition on a carrier film and drying the resulting dry film. Obtained by hardening the coating film laminated on the substrate, and The electronic component is characterized by having the hardened material. [Effects of the invention]

According to the present invention, the problem of aggregation and precipitation of hydrophilic silica in the curable composition can be eliminated. When the curable composition is coated on the substrate, the (D) polysiloxane compound can maintain contact with the substrate. The wettability of the flux can also improve the wettability of the hardened product. Therefore, when the hardened product is used as a solder resist, the solderability improvement effect is obtained.

＜Cureable composition＞

The curable composition of the present invention contains: (A) Alkali-soluble resin, (B) Photopolymerization initiator, (C) Epoxy resin, (D)Polysilicone compound, (E) Hydrophilic silica, and (F) Organic thixotropic agent.

[(A) Alkali-soluble resin] Alkali-soluble resin is a resin that can dissolve the curable composition in an alkali developing solution, that is, it can be developed by alkali.

As the alkali-soluble resin, a carboxyl group-containing resin or a phenol resin is preferably used. In particular, the use of a carboxyl group-containing resin is preferable in terms of developability.

As the carboxyl group-containing resin, various conventionally known carboxyl group-containing resins may be used that have a carboxyl group in the molecule and do not have an ethylenically unsaturated group (non-photosensitive) or have an ethylenically unsaturated group (photosensitive).

In the present invention, the so-called ethylenically unsaturated group is a substituent having an ethylenically unsaturated bond. Examples thereof include vinyl and (meth)acrylyl. From the viewpoint of reactivity, (meth)acryl is preferred. Jiji. Here, (meth)acrylyl group is a general term for acrylyl group and methacrylyl group.

Specific examples of the carboxyl group-containing resin having no ethylenically unsaturated group include the following compounds (any of oligomers and polymers).

(1) By combining diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, etc., and dimethylol propionic acid, dimethylol butyric acid, etc. containing carboxyl groups Diol compounds, polycarbonate polyols, polyether polyols, polyester polyols, polyolefin polyols, bisphenol A alkylene oxide adduct diols, with phenolic hydroxyl and alcohol properties Carboxyl group-containing urethane resin obtained by polyaddition reaction of glycol compounds such as hydroxyl compounds.

(2) Carboxyl group-containing urethane resin obtained by the polyaddition reaction of diisocyanate and carboxyl group-containing diol compound.

(3) By copolymerizing unsaturated carboxylic acids such as (meth)acrylic acid and unsaturated group-containing compounds such as styrene, α-methylstyrene, lower alkyl (meth)acrylate, isobutylene, etc. Resins containing carboxyl groups are obtained.

(4) React bifunctional epoxy resin or bifunctional oxetane resin with dicarboxylic acids such as adipic acid, phthalic acid, hexahydrophthalic acid, and add phthalic acid to the generated hydroxyl group. Carboxyl-containing polyester resin made from dibasic acid anhydrides such as formic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride.

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

(6) Reaction products and polybasic acid anhydrides equal to the number of polyhydric alcohols obtained by reacting a polyphenolic compound with a plurality of phenolic hydroxyl groups in one molecule and an alkylene oxide such as ethylene oxide or propylene oxide. Carboxyl-containing resin obtained by reaction.

Specific examples of the carboxyl group-containing resin having an ethylenically unsaturated group include the following compounds (any of oligomers and polymers). Furthermore, the ethylenically unsaturated bond in the carboxyl group-containing resin is preferably acrylic acid or methacrylic acid or a derivative thereof.

(7) Diols containing carboxyl groups such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, etc. and dimethylol propionic acid, dimethylol butyric acid, etc. Compounds, polycarbonate polyols, polyether polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A-based alkylene oxide adduct diols, phenolic hydroxyl groups and Photosensitive urethane resin containing carboxyl groups obtained by the polyaddition reaction of diol compounds such as alcoholic hydroxyl compounds.

(8) Mix diisocyanate with 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, Photosensitive polyurethane containing carboxyl groups obtained by the polyaddition reaction of (meth)acrylate or partial acid anhydride modifications of bifunctional epoxy resins such as phenolic epoxy resins and carboxyl group-containing glycol compounds resin.

(9) In the synthesis of the resin in the above (7) or (8), a compound having one hydroxyl group and one or more (meth)acrylyl groups in the molecule, such as hydroxyalkyl (meth)acrylate, is added. Photosensitive urethane resin containing carboxyl groups with terminal (meth)acrylation.

(10) In the resin synthesis of the above (8) or (9), molar reactants such as isophorone diisocyanate and pentaerythritol triacrylate are added which have one isocyanate group and more than one (methyl) group in the molecule It is a carboxyl-containing photosensitive urethane resin with terminal (meth)acrylation of acrylic compounds.

(11) A carboxyl group-containing photosensitive resin in which a bifunctional or higher polyfunctional (solid) epoxy resin is reacted with (meth)acrylic acid to add a dibasic acid anhydride to the hydroxyl group present in the side chain.

(12) The hydroxyl group of a bifunctional (solid) epoxy resin is reacted with a polyfunctional epoxy resin epoxidized with epichlorohydrin and (meth)acrylic acid, and the carboxyl group-containing dibasic acid anhydride is added to the generated hydroxyl group. Sex resin.

(13) React bifunctional oxetane resin with dicarboxylic acids such as adipic acid, phthalic acid, and hexahydrophthalic acid, and add phthalic anhydride and tetrahydrophthalic anhydride to the resulting primary hydroxyl group. Polyester photosensitive resin containing carboxyl groups of dibasic acid anhydrides such as hydrogen phthalic anhydride and hexahydrophthalic anhydride.

(14) Reaction products of polyol resins, etc. obtained by reacting polyphenol compounds, which are compounds having plural phenolic hydroxyl groups in one molecule, and alkylene oxides such as ethylene oxide and propylene oxide, and (meth)acrylic acid The carboxyl group-containing photosensitive resin is obtained by reacting monocarboxylic acids containing unsaturated groups, and the reaction product obtained reacts with polybasic acid anhydrides.

(15) The reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethyl carbonate or propyl carbonate is reacted with a monocarboxylic acid containing an unsaturated group. A carboxyl-containing photosensitive resin obtained by reacting a reaction product with a polybasic acid anhydride.

(16) A carboxyl group-containing photosensitive resin obtained by adding a compound having one epoxy group and one or more (meth)acrylyl groups per molecule to the resins of the above (7) to (15).

These photosensitive carboxyl group-containing resins can also be used other than those described in (7) to (16). One type can be used alone, or a plurality of types can be mixed and used. In particular, resins having an aromatic ring are preferred among resins containing carboxyl groups.

The following can be said for the above-mentioned carboxyl group-containing resin regardless of whether it is photosensitive or non-photosensitive. That is, since it has many carboxyl groups in the main chain and side chains of the polymer, it can be developed with a dilute alkali aqueous solution.

The acid value of the carboxyl group-containing resin is preferably in the range of 40 to 200 mgKOH/g, more preferably in the range of 45 to 120 mgKOH/g. When the acid value of the carboxyl-containing resin is within this range, alkali development becomes easier, the dissolution of the exposed part by the developing solution can be suppressed, the lines will not be too thin, and the developing solution will not dissolve and peel, and normal drawings can be achieved. graphics.

In addition, the weight average molecular weight of the above-mentioned carboxyl group-containing resin varies depending on the resin skeleton, but is preferably in the range of 2,000 to 150,000, and more preferably 5,000 to 100,000. If the weight average molecular weight is within this range, the non-tackiness properties will be good, the moisture resistance of the coating film after exposure will be good, and the developability, resolution, and storage stability will be excellent. The compounding amount of these carboxyl group-containing resins in the curable composition (solid content) is in the range of 20 mass% or more and 80 mass% or less, preferably 30 mass% or more and 70 mass% or less. If the compounding amount of the carboxyl group-containing resin is within this range, the coating film strength will not be reduced, and the viscosity will not be increased or the workability will be reduced.

Furthermore, in the present invention, as (A) the alkali-soluble resin, either a photosensitive carboxyl group-containing resin or a non-photosensitive carboxyl group-containing resin can be used, or these can be mixed and used.

The phenol resin is a compound having a phenolic hydroxyl group, for example, a compound having a biphenyl skeleton or a phenylene skeleton or both skeletons, or a compound containing a phenolic hydroxyl group such as phenol, o-cresol, p-cresol, m-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol Phenol, catechol, resorcinol, hydroquinone, methylhydroquinone, 2,6-dimethylhydroquinone, trimethylhydroquinone, pyrogallol, Phenolic resins with various skeletons synthesized from phloroglucinol and others.

For example, phenol novolak resin, alkylphenol novolac resin, bisphenol A novolak resin, dicyclopentadiene type phenol resin, Xylok type phenol resin, terpene modified phenol resin, polyvinyl phenols, bisphenol can be used. F. Bisphenol S type phenol resin, poly-p-hydroxystyrene, condensate of naphthol and aldehydes, condensate of dihydroxynaphthalene and aldehydes, etc. are well-known and commonly used phenol resins.

These can be used individually or in combination of 2 or more types.

Examples of commercially available phenolic resins include HF-1M (manufactured by Meiwa Kasei Co., Ltd.), Phenolite TD-2090, Phenolite TD-2131 (manufactured by DIC Co., Ltd.), Besmol CZ-256-A (manufactured by DIC Co., Ltd.), Shonol BRG-555, Shonol BRG-556 (manufactured by AICA), CGR-951 (manufactured by Maruzen Oil Co., Ltd.), or polyvinyl phenol CST70, CST90, S-1P, S-2P (manufactured by Maruzen Oil Co., Ltd.), etc. These phenolic resins can be used individually or in combination of 2 or more types.

[(B) Photopolymerization initiator] (B) The photopolymerization initiator is added to start radical polymerization of ethylenically unsaturated groups by irradiation with energy rays.

(B) Examples of photopolymerization initiators include benzoin and benzoyl alkyl ethers such as benzoin, benzoin methyl ether, benzoin diethyl ether, benzoin isopropyl ether, etc.; acetophenone, 2 ,2-Dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, Acetophenones such as 1,1-dichloroacetophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl- 2-Dimethylamino-1-(4-morpholinylphenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1- Aminophenanones such as [4-(4-morpholinyl)phenyl]-1-butanone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, Anthraquinones such as 1-chloroanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone Thioxanthones such as ketones; acetals such as acetophenone dimethyl acetal, benzyl dimethyl acetal, etc.; diphenyls such as 4,4'-bis(diethylamino)benzophenone etc. Ketones; (2,6-dimethoxybenzyl)-2,4,4-pentylphosphine oxide, bis(2,4,6-trimethylbenzyl)-phenyl oxide Phosphines, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphinate, etc.; 1,2 -Octanedione, 1-[4-(phenylthio)-,2-(O-benzoyl oxime)], ethyl ketone, 1-[9-ethyl-6-(2-methylbenzyl) Oxime esters such as acyl)-9H-carbazol-3-yl]-,1-(O-acetyl oxime); various peroxides, titanocene-based starters, etc. These can also be combined with N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, 4-dimethylaminobenzoic acid amyl ester, triethylamine, triethanolamine Use in combination with tertiary amines, photosensitizers, etc. These photopolymerization initiators may be used individually or in combination of 2 or more types.

(B) The amount of the photopolymerization initiator in the curable composition of the present invention is in the range of 0.01 to 30 parts by mass relative to 100 parts by mass (solid content) of the alkali-soluble resin (A). It is best to prepare it within the range of 0.5 parts by mass or more and 20 parts by mass or less.

[(C)Epoxy resin] (C) The epoxy resin is a compound added in order to thermally harden the curable composition of the present invention.

(C) As the epoxy resin, a commonly used polyfunctional epoxy resin having at least two epoxy groups per molecule can be used. Examples of the (C) epoxy resin include jER828, jER834, jER1001, and jER1004 manufactured by Mitsubishi Chemical Corporation, EPICLON 840, EPICLON 850, EPICLON 850-S, EPICLON 1050, and EPICLON 2055 manufactured by DIC Corporation, and Tōto Kasei Corporation. EPOTOT YD-011, YD-013, YD-127, YD-128, D.E.R.317, D.E.R.331, D.E.R.661, D.E.R.664 manufactured by Dow Chemical Co., Ltd., Sumi-epoxy ESA-011, ESA-014 manufactured by Sumitomo Chemical Industries, Ltd. , ELA-115, ELA-128 and other bisphenol A-type epoxy resins (all are trade names); jER YL903 made by Mitsubishi Chemical Company, EPICLON 152 and EPICLON 165 made by DIC Company, EPOTOT YDB- made by Toto Chemical Company 400, YDB-500, D.E.R.542 manufactured by Dow Chemical Company, brominated epoxy resins such as Sumi-epoxy ESB-400, ESB-700 (all trade names) manufactured by Sumitomo Chemical Industry Company; jER manufactured by Mitsubishi Chemical Company 152. jER 154, D.E.N.431, D.E.N.438 made by Dow Chemical Co., Ltd., EPICLON N-730, EPICLON N-770, EPICLON N-865 made by DIC Co., Ltd., EPOTOT YDCN-701, YDCN-704 made by Toto Chemical Co., Ltd., Japan EPPN-201, EOCN-1025, EOCN-1020, EOCN-104S, RE-306, NC-3000 manufactured by Chemical Co., Ltd., Sumi-epoxy ESCN-195X, ESCN-220 manufactured by Sumitomo Chemical Industries, Ltd., Nippon Steel Chemical YDCN-700-2, YDCN-700-3, YDCN-700-5, YDCN-700-7, YDCN-700-10, YDCN-704, YDCN-704A made by the company, EPICLON N-680 made by DIC company, Novolak-type epoxy resins such as EPICLON N-690 and EPICLON N-695 (all are trade names); EPICLON 830 manufactured by DIC Corporation, jER 807 manufactured by Mitsubishi Chemical Corporation, EPOTOT YDF-170 and YDF manufactured by Toto Kasei Corporation - Bisphenol F-type epoxy resins such as 175 and YDF-2004 (all are trade names); EPOTOT ST-2004, ST-2007, ST-3000 (trade names) made by Toto Chemical Co., Ltd., and YX8034 made by Mitsubishi Chemical Co., Ltd. Hydrogenated bisphenol A type epoxy resin; jER 604 manufactured by Mitsubishi Chemical Company, EPOTOT YH-434 manufactured by Toto Chemical Industry Company; Sumi-epoxy ELM-120 manufactured by Sumitomo Chemical Industry Company, etc. (all are trade names) Glyceryl amine type epoxy resin; hydantoin type epoxy resin; alicyclic epoxy resin such as Celloxide 2021 manufactured by Dicel Chemical Industry Co., Ltd. (all are trade names); YL-933 manufactured by Mitsubishi Chemical Co., Ltd., Japaneseized Trihydroxyphenylmethane type epoxy resins such as EPPN-501 and EPPN-502 (all are trade names) manufactured by pharmaceutical companies; YL-6056, YX-4000, YL-6121 (all are trade names) manufactured by Mitsubishi Chemical Corporation ) and other bisxylenol type or bisphenol type epoxy resins or mixtures thereof; EBPS-200 manufactured by Nippon Chemical Company, EPX-30 manufactured by ADEKA Company, EXA-1514 (trade name) manufactured by DIC Company Bisphenol S-type epoxy resins such as jER 157S (trade name) manufactured by Mitsubishi Chemical Corporation, bisphenol A novolak-type epoxy resins such as jER YL-931 manufactured by Mitsubishi Chemical Corporation (all trade names) Tetrahydroxyphenyl ethane type epoxy resin; diglycidyl phthalate resin such as Blenmer DGT manufactured by Nippon Oils and Fats Co., Ltd.; heterocyclic type such as TEPIC manufactured by Nissan Chemical Industry Co., Ltd. (all are trade names), etc. Epoxy resin; Tetraglycidylxylylethane resin such as ZX-1063 made by Toto Chemical Co., Ltd.; ESN-190 and ESN-360 made by Nippon Steel Chemical Co., Ltd., HP-4032 and EXA made by DIC Co., Ltd. -Naphthyl-containing epoxy resins such as 4750 and EXA-4700; epoxy resins with dicyclopentadiene skeleton such as HP-7200 and HP-7200H manufactured by DIC; CP-50S and Glycidyl methacrylate copolymers such as CP-50M are epoxy resins; furthermore, there are copolymerized epoxy resins of cyclohexyl maleimide and glycidyl methacrylate; CTBN modified epoxy resin ( For example, YR-102, YR-450, etc. manufactured by Toto Kasei Co., Ltd.), etc., but are not limited to these.

When compounding (C) epoxy resin, it is compounded in the quantity which becomes 0.8 or more epoxy equivalents and 2.0 or less epoxy equivalents with respect to the carboxylic acid equivalent of (A) alkali-soluble resin. The carboxylic acid equivalent here means the weight of the alkali-soluble resin (A) necessary to obtain 1 mole of carboxyl groups, and the unit is g/mol. In addition, the epoxy equivalent means the weight of (C) epoxy resin necessary to obtain 1 mole of epoxy groups, and the unit is g/mol. The mass of (C) the epoxy resin is 0.8 or more epoxy equivalents and 2.0 or less epoxy equivalents relative to the carboxylic acid equivalent of (A) the alkali-soluble resin. When the epoxy equivalent is within these ranges, a cured product with excellent heat resistance, electrical properties, and crack resistance can be obtained.

[(D)Polysilicone compound] (D) The polysiloxane compound is formulated to improve the wettability of the curable composition of the present invention to the copper-clad substrate (base material), suppress non-adhesion, and improve leveling properties.

(D) The polysiloxane compound is polydimethylsiloxane or a derivative with polydimethylsiloxane as its basic structure, such as polydimethylsiloxane and polyether-modified polydimethylsiloxane. Oxane, polyester modified polydimethylsiloxane, polyester modified polymethylalkylsiloxane, polyether modified polymethylalkylsiloxane, aralkyl modified polymethane siloxane, polyether modified siloxane, polyester modified hydroxyl-containing polydimethylsiloxane, etc.

Examples of commercially available products of the (D) polysiloxane compound include BYK (registered trademark)-300, BYK (registered trademark)-302, BYK (registered trademark)-306, BYK (registered trademark)-307, BYK (registered trademark) )-310, BYK (registered trademark)-315N, BYK (registered trademark)-320, BYK (registered trademark)-322, BYK (registered trademark)-323, BYK (registered trademark)-325, BYK (registered trademark)- 330, BYK (registered trademark)-331, BYK (registered trademark)-333, BYK (registered trademark)-342, BYK (registered trademark)-345, BYK (registered trademark)-346, BYK (registered trademark)-347, BYK (registered trademark)-348, BYK (registered trademark)-349, BYK (registered trademark)-370, BYK (registered trademark)-377, BYK (registered trademark)-378, BYK (registered trademark)-3455 (the above are Made by BYK Corporation of Japan).

(D) The polysiloxy compound in the curable composition of the present invention is in the range of 0.1 to 10 parts by mass relative to 100 parts by mass (solid content) of the alkali-soluble resin (A), preferably 1 part by mass It is prepared within the range of more than 5 parts by mass and less than 5 parts by mass. By setting the (D) polysiloxane compound in the range of 0.1 parts by mass or more and 10 parts by mass or less, the wettability of the curable composition to the copper-clad substrate (base material) can be ensured, the leveling properties can be improved, and the flux can be The wettability of the hardened material also becomes good.

[(E) Hydrophilic silica] (E) Hydrophilic silica is added in order to suppress the curing shrinkage of the curable composition of the present invention and to enhance the rigidity of the obtained cured product.

In the present invention, (E) hydrophilic silica refers to untreated silica that has not been subjected to surface treatment to add a hydrophobic organic group to its hydrophilic surface. Examples include fused silica, spherical silica, Amorphous silica, crystalline silica, etc.

In addition, the surface treatment of adding a hydrophobic organic group means treating (untreated) hydrophilic diodes with a coupling agent having a hydrophobic organic group such as an ethylenically unsaturated group (photocurable reactive group), an alkyl group, etc. The silicon oxide surface and the surface-treated silicon oxide are not included in the above-mentioned (E) hydrophilic silicon dioxide.

Examples of commercially available products include FB-15D, FB-105, FB-105X, FB-5SDX, SFP-20M, SFP-130MC (the above are manufactured by Denki Chemical Industry Co., Ltd.), EXCELICA (registered trademark) (Tokuyama Co., Ltd. Co., Ltd.), SR-NP (manufactured by M.TEC Chemical Co., Ltd.), etc.

(E) When hydrophilic silica is used to form a cured film on a printed wiring board, the median diameter (D50) is 30 μm or less. When used to form a cured film on an IC package substrate, the median diameter (D50) is 5 μm or less. A range of 0.2 μm to 2 μm is preferable from the viewpoint of dispersibility in the curable composition. In addition, the measurement method of the median diameter (D50) is as follows.

＜Measurement method of median diameter (D50)＞ Put 30 ml of ethanol and 1 g of silica powder into a beaker with a capacity of 100 ml, stir it for 3 minutes in a desktop ultrasonic cleaner, and use a laser diffraction/scattering particle size distribution meter (MICROTRAC BEL company) MT-3300, measure the volume-based median diameter (D50) in ethanol solvent.

Moreover, (E) hydrophilic silica is preferably in the range of 10 to 200 parts by mass relative to 100 parts by mass (solid content) of the alkali-soluble resin (A) in the curable composition of the present invention. It is prepared within the range of 20 parts by mass or more and 180 parts by mass or less. By setting (E) hydrophilic silica in the range of 10 parts by mass or more and 200 parts by mass or less, the effect of suppressing curing shrinkage and strengthening the rigidity of the cured product can be obtained, and the dispersibility is also good.

[(F) Organic thixotropic agent] (F) The organic thixotropic agent is used to inhibit the aggregation and precipitation of (E) hydrophilic silica in the curable composition of the present invention, and as originally understood in the present invention, to improve the hardening of the flux for the present invention. It is added to improve the wettability of the hardened material of the sexual composition.

(F) organic thixotropic agents that can be used in the curable composition of the present invention include fatty acid amides (arylamide wax series) synthesized from vegetable oil fatty acids and amines; fatty acid esters, polyethers, sulfated Surfactant systems such as oils and higher alcohol sulfate esters; polycarboxylate esters; polycarboxylic acid amides; urea modified compounds, but excluding hydrogenated castor oil systems called castor oil waxes and polyethylene Oxidized polyethylene series that introduces wax with polar groups through oxidation treatment.

Examples of commercially available products as (F) organic thixotropes include BYK (registered trademark)-R606, BYK (registered trademark)-405, BYK (registered trademark)-R605, BYK (registered trademark)-R607, BYK (registered trademark) )-410, BYK (registered trademark)-411, BYK (registered trademark)-415, BYK (registered trademark)-430, BYK (registered trademark)-431, BYK (registered trademark)-7410ET, BYK (registered trademark)- 7411ES (the above are made by BYK Corporation of Japan), TALEN 1450, TALEN 2000, TALEN 2200A, TALEN 7200-20, TALEN 8200-20, TALEN 8300-20, TALEN 8700-20, TALEN BA-600, FLOWNON SH-290, FLOWNON SH-295S, FLOWNON SH-350, FLOWNON HR-2, FLOWNON HR-4AF (the above are manufactured by Kyeisha Chemical Co., Ltd.).

(F) The organic thixotrope in the curable composition of the present invention is 0.01 to 15 parts by mass, preferably 0.05 parts by mass, based on 100 parts by mass (solid content) of (E) hydrophilic silica. 10 parts by mass or less.

Moreover, the (F) organic thixotrope in the curable composition of the present invention is 0.05 parts by mass or more, preferably 0.1 part by mass or more based on 2 parts by mass of the (D) polysiloxane compound.

By being within the above range, (E) hydrophilic silica is well dispersed, and the flux has good wettability with respect to the cured product of the curable composition.

[(G) Antioxidant] The curable composition of the present invention preferably adds (G) antioxidant. (G) The antioxidant improves the adhesion between the base material and the curable composition by inhibiting copper oxidation of the copper-clad substrate (base material).

Examples of (G) antioxidants include hindered phenol compounds such as 3-(N-salicylicyl)amino-1,2,4-triazole, sulfur-based antioxidants such as zinc salts of 2-mercaptobenzimidazole, and triazole. Phosphorus-based antioxidants such as benzene phosphine, aromatic amine-based antioxidants such as di-tert-butyldiphenylamine, etc. Heterocyclic formulas containing nitrogen as heteroatoms such as melamine, benzotriazole, tolyltriazole, etc. Compounds (except sulfur antioxidants), etc. Among them, melamine is preferred.

The compounding amount of (G) antioxidant in the curable composition of the present invention is 0.1 to 5 parts by mass, preferably 0.5 part by mass relative to 100 parts by mass (solid content) of the alkali-soluble resin (A) 2 parts by mass or less.

[Other ingredients] Furthermore, it is preferable to add a photopolymerizable polyfunctional monomer to the curable composition of the present invention. A compound in which the photopolymerizable polyfunctional monosystem has two or more ethylenically unsaturated groups in one molecule (when (A) the alkali-soluble resin contains an ethylenically unsaturated group) contributes to the activity through The alkali-soluble resin (A) is photocured by irradiation with energy rays, and is used for photocuring the curable composition.

Examples of compounds used as photopolymerizable polyfunctional monomers include commonly known polyester (meth)acrylates, polyether (meth)acrylates, urethane (meth)acrylates, and carbonates. (meth)acrylate, epoxy (meth)acrylate, etc. Specific examples include polyols such as hexylene glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, tri-hydroxyethyl isocyanurate, or their ethylene oxide adducts and propylene oxide adducts. , or polyacrylates such as ε-caprolactone adducts; phenoxy acrylate, bisphenol A diacrylate, and ethylene oxide adducts or propylene oxide adducts of these phenols Polyacrylic acid esters of glycidyl ethers such as glycerol diglycidyl ether, glyceryl triglycidyl ether, trimethylolpropane triglycidyl ether, triglycidyl isocyanurate, etc.; Not limited to the above, but may be direct acrylation of polyols such as polyether polyol, polycarbonate diol, hydroxyl-terminated polybutadiene, polyester polyol, or urethane acrylate via diisocyanate group At least any one of acrylates, melamine acrylates, and methacrylates corresponding to the above-mentioned acrylates.

In the curable composition of the present invention, the photopolymerizable polyfunctional monomer is in the range of 3 parts by mass to 30 parts by mass, preferably 10 parts by mass, based on 100 parts by mass (solid content) of the alkali-soluble resin (A) It is prepared within the range of above 20 parts by mass and below.

The curable composition of the present invention preferably further contains curing catalysts such as dicyanodiamide, boron trifluoride-amine catalyst, and organic acid hydrazine. The curing catalyst is added to the curable composition of the present invention in an amount of 5 parts by mass or less, preferably in an amount ranging from 0.1 part by mass to 2 parts by mass, based on 100 parts by mass (solid content) of the alkali-soluble resin (A). .

Furthermore, for the purpose of coloring, coloring pigments, dyes, etc. may be added to the curable composition of the present invention. As coloring pigments, dyes, etc., those conventionally expressed by color indexes can be used. Examples include Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 60, Solvent Blue 35, 63, 68, 70, 83, 87, 94, 97, 122 , 136, 67, 70, pigment green 7, 36, 3, 5, 20, 28, solvent yellow 163, pigment yellow 24, 108, 193, 147, 199, 202, 110, 109, 139, 179, 185, 93 ,94,95,128,155,166,180,120,151,154,156,175,181,1,2,3,4,5,6,9,10,12,61,62,62:1 ,65,73,74,75,97,100,104,105,111,116,167,168,169,182,183,12,13,14,16,17,55,63,81,83,87 , 126, 127, 152, 170, 172, 174, 176, 188, 198, Pigment Orange 1, 5, 13, 14, 16, 17, 24, 34, 36, 38, 40, 43, 46, 49, 51 , 61, 63, 64, 71, 73, pigment red 1, 2, 3, 4, 5, 6, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 112 ,114,146,147,151,170,184,187,188,193,210,245,253,258,266,267,268,269,37,38,41,48:1,48:2,48 :3, 48:4, 49:1, 49:2, 50:1, 52:1, 52:2, 53:1, 53:2, 57:1, 58:4, 63:1, 63:2 , 64:1, 68, 171, 175, 176, 185, 208, 123, 149, 166, 178, 179, 190, 194, 224, 254, 255, 264, 270, 272, 220, 144, 166, 214 , 220, 221, 242, 168, 177, 216, 122, 202, 206, 207, 209, solvent red 135, 179, 149, 150, 52, 207, pigment purple 19, 23, 29, 32, 36, 38 , 42, solvent violet 13, 36, pigment brown 23, 25, pigment black 1, 7, etc. Such coloring pigments. The dye and the like may be added in an amount ranging from 0.01 to 5 parts by mass, preferably from 0.1 to 3 parts by mass, based on 100 parts by mass of the curable composition.

Furthermore, as needed, conventionally used polymerization inhibitors, photopolymerization sensitizers, etc., such as hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, and phenothiazine, can be adjusted. Light stabilizers, flame retardants, flame retardant auxiliaries, etc. are commonly used additives.

In addition, the curable composition of the present invention may also contain an organic solvent for adjusting the viscosity. As organic solvents, ketones such as methyl ethyl ketone and cyclohexanone can be used; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellulose, methyl cellulose, butyl cellulose, and carbisol. Alcohol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether (DPM), dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether and other glycol ethers; ethyl acetate, acetic acid Butyl ester, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether Esters such as acetate and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, naphtha, solvent naphtha, etc. These organic solvents can be used alone or in combination of two or more.

<Dry film and cured product of the curable composition of the present invention> The curable composition of the present invention can be coated on a carrier film (support) and dried to form a dry film. During dry film formation, the curable composition of the present invention is diluted with the above-mentioned organic solvent to adjust to an appropriate viscosity, and is applied using a notch wheel coater, a blade coater, a lip die coater, a rod coater, or a rubber roller. Use a spreader, reverse roller coater, transfer roller coater, gravure coater, spray coater, etc. to coat the carrier film with a uniform thickness. Usually, dry at a temperature of 50~130°C for 1~30 minutes. A dry coating film is available. The coating film thickness is not particularly limited, but generally the film thickness after drying is within the range of 0.1 to 100 μm, preferably 0.5 to 50 μm.

As the carrier film, a plastic film is used, and plastic films such as polyester film such as polyethylene terephthalate, polyimide film, polyimide film, polypropylene film, and polystyrene film can be used. . The thickness of the carrier film is not particularly limited, but is generally appropriately selected within the range of 0.1 to 150 μm.

In this case, after the coating film is formed on the carrier film, it is preferable to laminate a peelable cover film on the surface of the coating film for the purpose of preventing dust and the like from adhering to the surface of the coating film. The peelable covering film can be, for example, polyethylene film, polytetrafluoroethylene film, polypropylene film, surface-treated paper, etc., as long as the adhesion force between the coating film and the cover film is less than the bonding force between the coating film and the carrier film when peeling off the covering film. Then force it.

Moreover, regarding the curable composition of the present invention, after using the above-mentioned organic solvent to adjust the viscosity suitable for the coating method, it is applied to the base material by a dip coating method, a flow coating method, a roll coating method, or a rod coating method. Coating by cloth method, screen printing method, curtain coating method, die nozzle coating method, etc., at about 50℃~ The temperature of 90°C causes the organic solvent contained in the composition to evaporate and dry (temporarily dry), forming a dry coating film that is non-tacky. In addition, when the curable composition of the present invention is applied to a carrier film and then dried to form a film and rolled up as a dry film, the coating film of the curable composition is brought into contact with the base material using a laminator or the like. After being bonded to the base material, the carrier film is peeled off, thereby forming a coating layer on the base material.

These coating films can be photocured by, for example, active energy ray irradiation, or thermally cured by heating to a temperature of 100°C to 250°C to obtain a cured product.

Examples of the above-mentioned substrate include a printed wiring board or a flexible printed wiring board with circuits formed in advance. In addition, examples include paper + phenol resin, paper + epoxy resin, paper + glass cloth + epoxy resin, glass nonwoven fabric + epoxy resin, Copper-clad laminates of glass fabric + epoxy resin, glass fiber + polyimide resin, etc.

The volatilization drying after applying the curable composition of the present invention can use a hot air circulation drying oven, an IR oven, a heating plate, a forced oven, and other heat sources equipped with an air heating method using steam to make hot air convection contact in the dryer. method and the method of using a nozzle to blow the support body.

The exposure machine used for the above-mentioned active energy ray irradiation may be a device equipped with a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a mercury arc lamp, etc., and can irradiate ultraviolet rays in the range of 350 to 450 nm. Direct drawing may also be used. Devices (such as direct imaging devices that draw images by directly irradiating active energy rays from CAD data from a computer). As the light source of the direct drawing machine, it is sufficient to use one with a maximum wavelength in the range of 350~410nm. The exposure amount used for image formation varies depending on the film thickness, etc., but is generally in the range of 20 to 1000 mJ/cm ² , preferably in the range of 20 to 800 mJ/cm ² .

In addition, as the developing method, dipping method, rinsing method, spray method, brushing method, etc. can be used. As the developer, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, and sodium silicate can be used. , ammonia, amines, etc. alkali aqueous solution.

In this way, the dry film and cured product obtained from the curable composition of the present invention have excellent heat resistance, rigidity, adhesion to the substrate, and insulation properties, so they can be applied to various applications, and the applicable objects are not particularly limited. For example, it can be used as an etching resist, solder resist, standard resist, etc. for manufacturing printed wiring boards. Among them, since the solderability is improved, it can be preferably used as a solder resist that requires high heat resistance.

＜Electronic components using a cured product of a curable composition as an insulating cured film＞ When the cured product of the curable composition pattern-printed on the base material is used as a solder resist, it is heated during the soldering step for component mounting. Hand soldering can be performed by flow soldering, reflow soldering, etc., but for example, during reflow soldering, it is necessary to preheat at 100℃~140℃ for 1~4 hours, and then heat at 240℃~280℃ for 5 hours The resoldering step of heating and melting is repeated several times (for example, 2 to 4 times) for about 20 seconds. After cooling, the parts are installed as needed to complete the electronic parts.

The following examples are shown to illustrate the present invention in detail, but the present invention is not limited to these examples. In addition, in the following, "parts" means parts by mass unless otherwise specified. [Example]

(Synthesis of alkali-soluble resin) [Synthesis example 1] Dissolve 380 parts of bisphenol F epoxy resin (epoxy equivalent 950g/eq, softening point 85°C) and 925 parts of epichlorohydrin in 462.5 parts of dimethylsulfoxide, and add 98.5 parts over 100 minutes at 70°C while stirring. %NaOH 60.9 parts. After addition, reaction was further carried out at 70°C for 3 hours. After the reaction was completed, 250 parts of water was added for washing. After the oil and water are separated, most of the dimethyl sulfoxide and excess unreacted epichlorohydrin are recovered from the oil layer by distillation under reduced pressure. The remaining reaction product containing by-product salts and dimethyl sulfoxide is dissolved in methyl isobutyl ketone 750 parts, further add 10 parts of 30% NaOH, and react at 70°C for 1 hour. After the reaction, wash twice with 200 parts of water. After the oil and water are separated, methyl isobutyl ketone is recovered by distillation from the oil layer to obtain epoxy resin (a) with an epoxy equivalent of 310 g/eq and a softening point of 69°C. If the obtained epoxy resin (a) is calculated based on the epoxy equivalent, approximately 5 of the 6.2 alcoholic hydroxyl groups in the bisphenol F-type epoxy resin as the starting material have been epoxidized. 310 parts of the epoxy resin (a) and 282 parts of carbitol acetate were put into a flask, heated, stirred and dissolved at 90°C. The resulting solution was temporarily cooled to 60°C, and 72 parts (1 mol) of acrylic acid, 0.5 parts of methylhydroquinone, and 2 parts of triphenylphosphine were added, heated to 100°C, and reacted for about 60 hours to obtain an acid value of 0.2 mgKOH/ g reactant. Add 140 parts (0.92 mol) of dry tetrahydrophthalic acid to it, heat to 90°C to react, and obtain a photosensitive carboxyl-containing resin varnish (A-1). The obtained carboxyl group-containing resin varnish (A-1) had a solid content concentration of 62.5% and a solid acid value (mgKOH/g) of 100.

[Synthesis example 2] Cresol novolak type epoxy resin (manufactured by Dainippon Ink Chemical Industry Co., Ltd., registered trademark "EPICLON" N-695, epoxy equivalent: 220) 220 parts are fed into a four-neck flask equipped with a mixer and a sulfur return cooler. , add 214 parts of carbitol acetate and heat to dissolve. Next, 0.1 part of hydroquinone as a polymerization inhibitor and 2.0 part of dimethylbenzylamine as a reaction catalyst were added. The mixture was heated at 95~105°C, 72 parts of acrylic acid was slowly added dropwise, and the reaction was carried out for 16 hours. The reaction product was cooled to 80~90°C, 106 parts of tetrahydrophthalic anhydride was added, the reaction was carried out for 8 hours, and then taken out after cooling. The photosensitive resin thus obtained having both ethylenically unsaturated bonds and carboxyl groups has a non-volatile content of 65%, an acid value of solid content of 85 mgKOH/g, and a weight average molecular weight Mw of approximately 3,500. This resin solution will be called varnish (A-2) below. In addition, the weight average subweight of the obtained resin was measured using three connected high-speed liquid chromatographs with pumps LC-804, KF-803, and KF-802 manufactured by Shimadzu Corporation.

<1. Preparation of curable compositions of Examples 1 to 9 and Comparative Examples 1 to 3> The resin solution of the preparation example and each material shown in Table 1 were separately prepared, premixed with a mixer, and then kneaded with a three-roller mill to prepare a curable composition. In Table 1, (A-1) to (A-3) represent the parts by mass of the resin solution each containing the solvent.

The following characteristic tests were performed on each of the above compositions. The results are shown in Table 1.

＜2. Evaluation of the non-adhesion and leveling properties of the hardened hard composition to the substrate＞ On the copper-clad substrate (base material) whose surface has been roughened by chemical polishing treatment, use a screen plate (Titron 100 mesh) to harden <1. Examples 1 to 9 and Comparative Examples 1 to 3 Preparation of the curable composition > Each curable composition adjusted in the middle is printed on the entire surface of the copper-clad substrate so that the film thickness is 10 μm.

Visually observe the coating film immediately after printing to confirm whether the curable composition does not stick to it and is in a leveled state (smoothness). Next, dry the printed circuit board at 80°C for 30 minutes, return to room temperature, and visually confirm the coating film state after drying. (Also, although visual confirmation is used in this example, when visual judgment is difficult, a surface roughness measuring machine (SurfCorder: manufactured by Kosaka Laboratory Co., Ltd.) or a shape measuring laser microscope (VK-X-100) may also be used. /KEYENCE Co., Ltd.) observe the surface roughness). The evaluation criteria are as follows.

○: No adhesion or screen marks △: There is non-sticking and no traces of the screen, or there is no non-sticking and there are traces of the screen. ×: There is no adhesion, and there are traces of the screen

＜3. Evaluation of flux non-adhesion＞ Using a screen (Titron 100 mesh), print each curable composition adjusted in <1. Preparation of Curable Compositions of Examples 1 to 4 and Comparative Examples 1 to 4> on a surface treated with chemical polishing. The surface of the 150×95mm, 1.6mm thick FR-4, 35μm thick copper substrate was roughened to a film thickness of 10μm over the entire surface.

After drying at 80°C for 30 minutes, use an exposure mask of 95×150mm size to form the pattern at 600mJ/ ^cm2 for exposure, and perform alkali development (1% Na ₂ CO ₃ aqueous solution, 30°C, 60 seconds development ), after thermal hardening at 150°C/60 minutes, perform UV treatment at 1000mJ/ ^cm2 .

The FR-4 substrate (base material) to which the cured product of the curable composition is fixed is subjected to electroless Sn plating (Sn: 1.1 μm/Tsukada Riken Industry Co., Ltd.), and the reflow step is repeated from 1 to 3 times. (265℃), before the reflow step after electrolytic Sn plating, after the reflow step once, after the reflow step twice, and after the reflow step three times, hardening of the fixed hardenable composition Wet tension test was performed on the FR-4 substrate of the product.

The wet tension test was conducted based on JIS K6768. As the wet tension test mixture, "Wet Tension Test Mixture No. 60.0" was used after the electroless Sn plating process and before the reflow step, and was used after the reflow step once. "Mixed solution for wet tension test NO.38.0", use "mixed solution for wet tensile test NO.36.0" after the reflow step 2 times, use "mixed solution NO.34.0 for wet tensile test" after the reflow step 3 times ". The mixed solution for any wet tension test was manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. In addition, the NO. of each mixed liquid represents the surface tension of the mixed liquid (unit: mN/m).

Specifically, the wet tension test is drawn with a cotton swab with the mixed liquid for the wet tension test, and the liquid film state is observed after 2 seconds. Furthermore, it is judged as wet when the liquid film does not break and remains in the coating state for more than 2 seconds.

In addition, the higher the numerical value of the mixed solution for the wet tension test, the better the flux non-stick property. Therefore, the wet tension test was set as a test to evaluate the flux non-stick property.

In Table 1, the evaluation criteria are as follows.

○: Wetting (no non-sticking) was judged in all stages after electroless Sn plating, before the reflow step to after three reflow steps.

×: After the electroless Sn plating process, before the reflow step and after the reflow step three times, there were cases where it was judged that no moisturizing was applied once (there was no adhesion).

*1: CYCLOMER P(ACA) Z250 (solid content 45wt%, unsaturated group-containing carboxyl group-containing copolymer resin solution, manufactured by DAICEL Chemical Co., Ltd.) *2: 2,4,6-trimethylbenzyldiphenylphosphine oxide (Omnirad TPO H: manufactured by IGM Resins B.V.) *3: 2-Dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one (Omnirad 379: IGM Resins B.V. (made) *4: Bisphenol A type epoxy resin (JER (registered trademark)-834: manufactured by Mitsubishi Chemical Corporation) *5: Triglycidyl isocyanurate (TEPIC-HP: manufactured by Nissan Chemical Industries, Ltd.) *6: Polyester modified polydimethylsiloxane (BYK (registered trademark)-313: manufactured by Japan BYK Corporation) *7: Polyether modified polydimethylsiloxane (BYK (registered trademark)-300: manufactured by Japan BYK Corporation) *8: Spherical silica (D50=0.6μm) (SFP-130MC: Made by Denki Chemical Industry Co., Ltd.) *9: Spherical silica (D50=0.4μm) (SFP-20M: Made by Denki Chemical Industry Co., Ltd.) *10: Polyhydroxycarboxylate (BYK (registered trademark)-R 606: manufactured by Japan BYK Corporation) *11: Melamine (Melamine: manufactured by Nissan Chemical Industry Co., Ltd.) *12: Spherical silica with surface treated with methacrylic alkane (1.5 μm SM-C4: manufactured by ADOMATEX Corporation) *13: Dipentaerythritol hexaacrylate (DPHA: manufactured by Nippon Kayaku Co., Ltd.) *14: Dicyanodiamide (C0454: manufactured by Tokyo Chemical Industry Co., Ltd.) *15: Blue pigment (Fastogen Blue-5380: manufactured by DIC Corporation). Table 1 shows the solid content by mass. *16: Yellow pigment (Cromophtal (registered trademark) Yellow S1515: manufactured by BASF Co., Ltd.). Table 1 shows the solid content by mass. *17: Dipropylene glycol methyl ether (Dowanol (registered trademark) DPM: manufactured by Nippon Do Chemical Co., Ltd.)

As shown in the examples in Table 1, when (D) polysiloxy compound, (E) hydrophilic silica and (F) organic thixotrope are formulated, the curable composition of the present invention is maintained against the copper substrate ( The wettability and leveling properties of the substrate) are also good, and (E) the hydrophilic silica does not agglomerate or precipitate. Furthermore, when the wet tension test mixture was applied to a base material having a cured product of the curable composition of the present invention fixed thereto, the wet tensile test mixture did not adhere to the cured product, and the wet tensile test was maintained. Use the mixture to improve the wettability of the hardened material.

On the other hand, in Comparative Example 1 in which hydrophobic treatment was applied to the surface of silica, even if (F) organic thixotropic agent was blended, the mixed liquid for the wet tension test was used to test the base of the cured product to which the curable composition of the present invention was fixed. If the wettability of the material is still reduced, it is considered that the weldability is reduced. Furthermore, in Comparative Example 2, which does not contain (F) organic thixotrope, even if (D) polysiloxane compound and (E) hydrophilic silica are blended, the mixed liquid for the wet tension test has the curable composition of the present invention. The wettability of the base material of the hardened material is still reduced, and the weldability is considered to be reduced. Furthermore, in Comparative Example 3 which does not contain (D) the polysiloxane compound, the wettability of the curable composition to the copper-clad substrate (base material) was insufficient, or the leveling property was deteriorated.

Claims (6)

A curable composition characterized by containing (A) alkali-soluble resin, (B) photopolymerization initiator, (C) epoxy resin, (D) polysiloxy compound, (E) hydrophilic silica, and (F) organic thixotropic agent, wherein the amount of (F) organic thixotropic agent is 0.01 to 15 parts by mass relative to 100 parts by mass of (E) hydrophilic silica, and relative to (D) 2 parts by mass of polysiloxy compound, which is 0.05 parts by mass or more. The curable composition of claim 1, wherein (E) the median diameter D50 of the hydrophilic silica is 0.2 μm or more and 2.0 μm or less. The curable composition of claim 1 or 2, further comprising (G) antioxidant. A dry film characterized by being obtained by applying the curable composition according to any one of claims 1 to 3 on a carrier film and drying it. A cured product characterized by being obtained by coating a curable composition as claimed in any one of claims 1 to 3 on a base material and drying the resulting dry coating film, or by coating the curable composition on a substrate. The dry film obtained by drying the carrier film is laminated on the base material and the coating film is hardened. An electronic component characterized by having a hardened object as claimed in claim 5.