WO2020194885A1

WO2020194885A1 - Curable composition, dry film, cured product, and electronic component

Info

Publication number: WO2020194885A1
Application number: PCT/JP2019/047556
Authority: WO
Inventors: 高木　幸一; 東海　裕之
Original assignee: 太陽インキ製造株式会社
Priority date: 2019-03-27
Filing date: 2019-12-05
Publication date: 2020-10-01
Also published as: TWI825246B; JP2023181436A; TW202035468A; JP7383388B2; JP2020161673A

Abstract

Provided are a curable composition, a dry film, a cured product, and an electronic component, said curable composition including an alkali-soluble resin (A), a photopolymerization initiator (B), an epoxy resin (C), a silicon compound (D), a hydrophilic silica (E), and an organic thixotropic agent (F). The curable composition contains hydrophilic silica and a silicon-based surface conditioner but also has good soldering properties and resolves the issues of silica flocculation and precipitation. As a result, the issues of flocculation and precipitation of hydrophilic silica inside a curable composition are resolved and, when the curable composition is coated upon a base material, the silicon compound (D) maintains base material wettability and, at the same time, improves flux wettability for the obtained cured product, thereby providing improved soldering properties when the cured product is used as a solder resist.

Description

Curable compositions, dry films, cured products and electronic components

The present invention relates to a curable composition, a dry film, a cured product and an electronic component, and more particularly to an alkali-developable curable composition, a dry film thereof, a cured product thereof and an electronic component including the cured product thereof.

Conventionally, in solder resists for consumer printed circuit boards and industrial printed wiring boards, from the viewpoint of high accuracy and high density, an image is formed by developing after irradiation with ultraviolet rays, and finish curing by heat and / or light irradiation ( Liquid-developing solder resists that undergo main curing) are used, and among liquid-developing solder resists, alkaline-developing photo solder resists that use an alkaline aqueous solution as the developer have become the mainstream in consideration of environmental issues. There is.

In general, a solder resist composition applied to a substrate for forming a photosolder resist on the substrate is used to improve the wettability of the solder resist composition to the substrate and to improve the leveling property (flatness) of the coating film. ) Is enhanced, a silicon-based surface conditioner is added.

After forming the photosolder resist on the substrate, the components are mounted on the substrate by soldering, but since molten solder has low wettability to the substrate, the wettability is improved (cleaning of the soldered surface and prevention of oxidation). ), The flux is applied to the entire surface of the substrate including the solder resist surface.

However, according to the study by the inventors, if the silicon-based surface conditioner is contained in the solder resist formed on the substrate, the flux is repelled from the substrate and the solderability is deteriorated. I understand.

On the other hand, it is well known that silica as an inorganic filler is added to the solder resist composition in order to strengthen the rigidity of the solder resist and suppress the curing shrinkage of the solder resist composition.

Patent Document 1 discloses, as an example thereof, an alkali-developing photocurable / thermosetting solder resist composition containing a silicon-based surface conditioner as the solder resist composition of the prior art, and Comparative Example 2 As an inorganic powder, an alkali-developed photocurable / thermosetting solder resist composition containing molten spherical silica that has not been subjected to surface modification treatment is disclosed.

JP-A-2009-194222

According to the alkali-developing photocurable / thermosetting solder resist composition containing the silicon-based surface conditioner according to the embodiment of Patent Document 1, the solder resist composition is formed although the wettability to the substrate is improved. Since the solder resist repels the flux, the solderability is deteriorated.

Further, according to the alkali-developing photocurable / thermosetting solder resist composition according to Comparative Example 2 of Patent Document 1, the added silica is not surface-modified and is hydrophilic. If it is left as it is, the problem of aggregation / precipitation may occur. For example, it is necessary to modify the surface to be hydrophobic to solve the problem of aggregation / precipitation. Further, since the alkali-developed photocurable / thermosetting solder resist composition according to Comparative Example 2 does not contain a silicon-based surface regulator, the wettability of the solder resist composition to the substrate is not improved.

The present invention has been made in view of the above problems, and an object of the present invention is to solve the problem of silica aggregation / precipitation with good solderability while containing hydrophilic silica and a silicon-based surface conditioner. It is an object of the present invention to provide a curable composition, a dry film, a cured product, and an electronic component.

The present inventors have made diligent studies to achieve the above object. As a result, surprisingly, when the silicone compound, the hydrophilic silica and the organic rocking agent were blended, the hydrophilic silica aggregated and precipitated while maintaining the wettability of the copper-clad substrate and the solder resist composition. We have found that the problem and the problem of flux repelling caused by the silicone compound have been solved, and have completed the present invention.

That is, the above object of the present invention is
(A) Alkali-soluble resin and
(B) Photopolymerization initiator and
(C) Epoxy resin and
(D) Silicone compound and
(E) Hydrophilic silica and
(F) Organic shaker and
It has been found that this is achieved with a curable composition characterized by containing.

In the curable composition of the present invention, the particle size median diameter D50 of (E) hydrophilic silica is preferably 0.2 μm or more and 2.0 μm or less.

Further, the amount of (F) organic rocking agent is 0.01 part by mass or more and 15 part by mass or less with respect to 100 parts by mass of (E) hydrophilic silica, and (D) with respect to 2 parts by mass of the silicone compound. It is more preferably 0.05 parts by mass or more.

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

Further, the above object of the present invention is a dry film obtained by applying the curable composition of the present invention on a carrier film and drying it.
A dry coating film obtained by applying the curable composition of the present invention on a substrate and drying it, or a dry film obtained by applying and drying the curable composition on a carrier film is used as a substrate. It can also be achieved by a cured product obtained by curing a laminated coating film and an electronic component characterized by including the cured product.

According to the present invention, the problem of aggregation and precipitation of hydrophilic silica in the curable composition is solved, and when the curable composition is applied to the base material, the (D) silicone compound is applied to the base material. Since the wettability is maintained and at the same time the wettability of the flux with respect to the obtained cured product is improved, the effect of improving the solderability can be obtained when the cured product is used as a solder resist.

<Curable composition>
The curable composition of the present invention is
(A) Alkali-soluble resin and
(B) Photopolymerization initiator and
(C) Epoxy resin and
(D) Silicone compound and
(E) Hydrophilic silica and
(F) Organic shaker and
including.

[(A) Alkali-soluble resin]
The alkali-soluble resin is a resin that enables the curable composition to be dissolved in an alkaline developer, that is, developed with an alkali.

As the alkali-soluble resin, it is preferable to use a carboxyl group-containing resin or a phenol resin. In particular, it is more preferable to use a carboxyl group-containing resin from the viewpoint of developability.

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

In the present invention, the ethylenically unsaturated group is a substituent having an ethylenically unsaturated bond, and examples thereof include a vinyl group and a (meth) acryloyl group. From the viewpoint of reactivity, a (meth) acryloyl group is used. Is preferable. Here, the (meth) acryloyl group is a general term for an acryloyl group and a meta-acryloyl group.

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

(1) Dialcohol compounds, polycarbonate-based polyols, which contain diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates, and carboxyl groups 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) Carboxylic 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, or 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 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 and aromatic diisocyanates, and carboxyl groups such as dimethylolpropionic acid and dimethylolbutanoic acid. Containing carboxyl group by multiple 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 obtained 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 resin of (7) or (8) described above, a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added, and the terminal is added. (Meta) Acryloylated carboxyl group-containing photosensitive urethane resin.

(10) During the synthesis of the resin according to (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 isomorphic reaction product. A carboxyl group-containing photosensitive urethane resin that is terminally (meth) acrylicized 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) Carboxylic acid obtained by reacting (meth) acrylic acid with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of a bifunctional (solid) epoxy resin with epichlorohydrin, and adding a dibasic acid anhydride to the generated hydroxyl groups. Group-containing photosensitive resin.

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

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

As these photosensitive 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.

The above-mentioned carboxyl group-containing resin can be said to be as follows regardless of whether it is photosensitive or non-photosensitive. That is, since the backbone polymer has a large number of carboxyl groups in the side chain, it can be developed with a dilute alkaline aqueous solution.

The acid value of the 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 becomes easy, dissolution of the exposed part by the developer is suppressed, the line is not thinned more than necessary, and there is no dissolution peeling by the developer. It is possible to draw a normal pattern.

The weight average molecular weight of the above-mentioned carboxyl group-containing resin varies depending on the resin skeleton, but is generally preferably in the range of 2,000 or more and 150,000 or less, and further 5,000 or more and 100,000 or less. When the weight 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 appropriate amount of such a carboxyl group-containing resin to be blended in the curable composition (solid content) is 20% by mass or more and 80% by mass or less, preferably 30% by mass or more and 70% by mass or less. When the blending amount of the carboxyl group-containing resin is within such a range, the strength of the coating film does not decrease, and the thickening and the workability do not decrease.

Further, in the present invention, as the alkali-soluble resin (A), either a photosensitive carboxyl group-containing resin or a non-photosensitive carboxyl group-containing resin may be used, or these may be mixed and used. It is possible.

Examples of the phenol resin include compounds having a phenolic hydroxyl group, for example, a compound having a biphenyl skeleton and / or a phenylene skeleton, or a phenolic hydroxyl group-containing compound, for example, phenol, orthocresol, paracresol, metacresol, 2 , 3-Xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, catechol, cresolsinol, hydroquinone, methylhydroquinone, 2,6-dimethylhydroquinone , Trimethylhydroquinone, pyrogallol, fluoroxylenol and the like, and phenolic resins having various skeletons may be used.

For example, phenol novolac resin, alkylphenol volac resin, bisphenol A novolak resin, dicyclopentadiene type phenol resin, Xyloc type phenol resin, terpene modified phenol resin, polyvinylphenols, bisphenol F, bisphenol S type phenol resin, poly-p- Known and commonly used phenolic resins such as hydroxystyrene, a condensate of naphthol and aldehydes, and a condensate of dihydroxynaphthalene and aldehydes can be used.

These can be used alone or in combination of two or more.

Commercially available products of such phenolic resins include HF-1M (manufactured by Meiwa Kasei Co., Ltd.), Phenolite TD-2090, Phenolite TD-2131 (manufactured by DIC Corporation), Vesmol CZ-256-A (manufactured by DIC Corporation), and Cyonol BRG. -555, Cyonor BRG-556 (manufactured by Aica Kogyo Co., Ltd.), CGR-951 (manufactured by Maruzen Petroleum Co., Ltd.), or polyvinylphenols CST70, CST90, S-1P, S-2P (manufactured by Maruzen Petroleum Co., Ltd.) Can be done. These phenolic resins can be used alone or in combination of two or more.

[(B) Photopolymerization Initiator]
(B) The photopolymerization initiator is added to initiate radical polymerization of the ethylenically unsaturated group by irradiation with energy rays.

(B) The photopolymerization initiator is, for example, benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin alkyl ethers; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-. Acetphenones such as diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 -On, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-Aminoalkylphenones such as -1-butanone; Anthracinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-terriary butyl anthraquinone, 1-chloroanthraquinone; 2,4-dimethylthioxanthone , 2,4-Diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone and other thioxanthones; acetophenone dimethyl ketal, benzyl dimethyl ketal and other ketals; 4,4'-bis (diethylamino) benzophenone and other benzophenones (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, Phosphine oxides such as ethyl-2,4,6-trimethylbenzoylphenylphosphinate; 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone, Oxim esters such as 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime); various peroxides, titanosen-based initiators, etc. Can be mentioned. These are photosensitized like tertiary amines such as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, triethanolamine and the like. It may be used in combination with an agent or the like. These photopolymerization initiators can be used alone or in combination of two or more.

The blending amount of the (B) photopolymerization initiator is in the range of 0.01 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass (solid content) of the (A) alkali-soluble resin in the curable composition of the present invention. , Preferably blended in 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 for thermosetting the curable composition of the present invention.

As the (C) epoxy resin, a known and commonly used polyfunctional epoxy resin having at least two epoxy groups in one molecule can be used. Examples of the epoxy resin (C) include jER828, jER834, jER1001, jER1004 manufactured by Mitsubishi Chemical Corporation, EPICLON840 and EPICLON850 manufactured by DIC, EPICLON850-S, EPICLON1050, EPICLON2055, and Epototo YD-011 manufactured by Toto Kasei Co., Ltd. -013, YD-127, YD-128, D.D. manufactured by Dow Chemical Corporation. E. R. 317, D.I. E. R. 331, D. E. R. 661, D.I. E. R. 664, Sumitomo Chemical Co., Ltd. Sumi-Epoxy ESA-011, ESA-014, ELA-115, ELA-128, etc. (all trade names) bisphenol A type epoxy resin; Mitsubishi Chemical Co., Ltd. jER YL903, DIC Corporation EPICLON152, EPICLON165, Epototo YDB-400, YDB-500 manufactured by Toto Kasei Co., Ltd., D.D. E. R. 542, Sumitomo Chemical's Sumi-Epoxy ESB-400, ESB-700, etc. (all trade names) brominated epoxy resins; Mitsubishi Chemical's jER152, jER154, Dow Chemical's D.D. E. N. 431, D.I. E. N. 438, DIC's EPICLON N-730, EPICLON N-770, EPICLON N-865, Toto Kasei's Epototo YDCN-701, YDCN-704, Nippon Kayakusha's EPPN-201, EOCN-1025, EOCN -1020, EOCN-104S, RE-306, NC-3000, Sumie Epoxy ESCN-195X, ESCN-220 manufactured by Sumitomo Chemical Industries, YDCN-700-2, YDCN-700-3 manufactured by Nippon Steel Chemical Co., Ltd. , YDCN-700-5, YDCN-700-7, YDCN-700-10, YDCN-704 YDCN-704A, EPICLON N-680 manufactured by DIC, EPICLON N-690, EPICLON N-695 (all trade names) Novolak type epoxy resin such as DIC; EPICLON 830 manufactured by DIC, jER807 manufactured by Mitsubishi Chemical Co., Ltd., Epototo YDF-170, YDF-175, YDF-2004 manufactured by Toto Kasei Co., Ltd., etc. Hydrophobic bisphenol A type epoxy resin such as Epototo ST-2004, ST-2007, ST-3000 (trade name) manufactured by Toto Kasei Co., Ltd., YX8034 manufactured by Mitsubishi Chemical Co., Ltd .; jER604 manufactured by Mitsubishi Chemical Co., Ltd., manufactured by Toto Kasei Co., Ltd. Epototo YH-434, Sumie Epoxy ELM-120 manufactured by Sumitomo Chemical Co., Ltd. (both trade names) glycidylamine type epoxy resin; Hidant-in type epoxy resin; Celoxide 2021 etc. manufactured by Daicel Chemical Industry Co., Ltd. (both trade names) ) Alicyclic epoxy resin; YL-933 manufactured by Mitsubishi Chemical Co., Ltd., EPPN-501, EPPN-502 manufactured by Nippon Kayaku Co., Ltd., etc. (all trade names) trihydroxyphenylmethane type epoxy resin; manufactured by Mitsubishi Chemical Co., Ltd. YL-6056, YX-4000, YL-6121 (all trade names) and other bixilenol-type or biphenol-type epoxy resins or mixtures thereof; EBPS-200 manufactured by Nippon Kayakusha, EPX-30 manufactured by ADEKA, DIC Bisphenol S type epoxy resin such as EXA-1514 (trade name) manufactured by Mitsubishi Chemical Co., Ltd .; Bisphenol A novolac type epoxy resin such as jER157S (trade name) manufactured by Mitsubishi Chemical Co., Ltd .; jER YL-931 etc. manufactured by Mitsubishi Chemical Co., Ltd. Tetraphenylol ethane type epoxy resin (trade name); Diglycidyl phthalate resin such as Blemmer DGT manufactured by Nippon Yushi Co., Ltd .; TEPIC manufactured by Nissan Chemical Industry Co., Ltd. (Name) heterocyclic epoxy resin; tetraglycidyl xylenoyl ethane resin such as ZX-1063 manufactured by Toto Kasei Co., Ltd .; ESN-190, ESN-360 manufactured by Nippon Steel Chemical Co., Ltd., HP-4032 manufactured by DIC Co., Ltd., EXA-4750. , EXA-4700 and other naphthalene group-containing epoxy resins; Epoxy resins having a dicyclopentadiene skeleton such as DIC's HP-7200 and HP-7200H; Nippon Oil & Fats' CP-50S, CP-50M and other glycidyl methacrylates Polymerized epoxy resin; further, copolymerized epoxy resin of cyclohexyl maleimide and glycidyl methacrylate; CTBN-modified epoxy resin (for example, YR-102, YR-450 manufactured by Toto Kasei Co., Ltd.) and the like, but are not limited thereto. Absent.

When (C) epoxy resin is blended, it is blended in an amount that is 0.8 epoxy equivalent or more and 2.0 epoxy equivalent or less with respect to the carboxylic acid equivalent of (A) alkali-soluble resin. Here, the carboxylic acid equivalent represents the weight of the (A) alkali-soluble resin required to obtain 1 mol of the carboxyl group, and the unit is g / mol. The epoxy equivalent represents the weight of the (C) epoxy resin required to obtain 1 mol of epoxy groups, and the unit is g / mol. The mass of the (C) epoxy resin is 0.8 epoxy equivalent or more and 2.0 epoxy equivalent or less with respect to the carboxylic acid equivalent of the (A) alkali-soluble resin. When the epoxy equivalent is within such a range, a cured product having excellent heat resistance, electrical characteristics, and crack resistance can be obtained.

[(D) Silicone compound]
The silicone compound (D) is blended to improve the wettability of the curable composition of the present invention with respect to the copper-clad substrate (base material), suppress its repelling, and improve the leveling property.

The silicone compound (D) is a polydimethylsiloxane or a derivative having a basic structure of polydimethylsiloxane, and is a polydimethylsiloxane, polyether-modified polydimethylsiloxane, polyester-modified polydimethylsiloxane, polyester-modified polymethylalkylsiloxane, or polyether. Examples thereof include modified polymethylalkylsiloxane, aralkyl-modified polymethylalkylsiloxane, polyether-modified siloxane, and polyester-modified hydroxyl group-containing polydimethylsiloxane.

Commercially available products of the silicone compound (D) include BYK (registered trademark) -300, BYK (registered trademark) -302, BYK (registered trademark) -306, BYK (registered trademark) -307, BYK (registered trademark) -10. , 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) Trademarks) -348, BYK (registered trademark) -349, BYK (registered trademark) -370, BYK (registered trademark) -377, BYK (registered trademark) -378, BYK (registered trademark) -3455 (above, Big Chemie Japan) Made by the company).

The silicone compound (D) is contained in the curable composition of the present invention in a range of 0.1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass (solid content) of the (A) alkali-soluble resin, preferably 1 part by mass. It is blended in the range of 5 parts by mass or more. When the silicone compound (D) is in the range of 0.1 parts by mass or more and 10 parts by mass or less, the wettability of the curable composition with respect to the copper-clad substrate (base material) is ensured, the leveling property is improved, and the leveling property is improved. The wettability of the flux with respect to the cured product is also good.

[(E) Hydrophilic silica]
(E) Hydrophilic silica is added to suppress 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 surface-treated to add a hydrophobic organic group to its hydrophilic surface, and is fused silica, spherical silica, or amorphous silica. , Crystalline silica and the like.

The surface treatment to which a hydrophobic organic group is added is, for example, a (untreated) hydrophilic coupling agent having a hydrophobic organic group such as an ethylenically unsaturated group (photocurable reactive group) or an alkyl group. It refers to treating the surface of the acidic silica, and the silica subjected to the surface treatment is not included in the hydrophilic silica (E).

Commercially available products include FB-15D, FB-105, FB-105X, FB-5SDX, SFP-20M, SFP-130MC (above, manufactured by Denki Kagaku Kogyo Co., Ltd.), Exe Silica (registered trademark) (manufactured by Tokuyama Corporation), SR-NP (manufactured by MTEC Chemical Co., Ltd.) and the like can be mentioned.

(E) The hydrophilic silica has a median diameter (D50) of 30 μm or less in an application for forming a cured film of a printed wiring board, and 5 μm or less in an application for forming a cured film on an IC package substrate, and has a median diameter (D50). When D50) is in the range of 0.2 μm or more and 2 μm or less, it is preferable from the viewpoint of dispersibility in the curable composition. The method for measuring the median diameter (D50) is as follows.

<Measurement method of median diameter (D50)>
Put 30 ml of ethanol and 1 g of silica powder in a beaker with a capacity of 100 ml, stir for 3 minutes in a desktop ultrasonic cleaner, and then use a laser diffraction / scattering particle size distribution meter (Microtrac Bell) Microtrack MT-3300. Then, the volume-based median diameter (D50) was measured with an ethanol solvent.

Further, (E) hydrophilic silica is preferably 20 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass (solid content) of the (A) alkali-soluble resin in the curable composition of the present invention. It is blended in the range of 1 part by mass or more and 180 parts by mass or less. When the hydrophilic silica is 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 is obtained, and the dispersibility is also good.

[(F) Organic shaker]
The (F) organic rocking agent is used for suppressing aggregation and precipitation of (E) hydrophilic silica in the curable composition of the present invention, and as was first revealed in the present invention, the curable property of the present invention. It is added to improve the wettability of the flux with respect to the cured product of the composition.

Examples of the (F) organic rocking agent that can be used in the curable composition of the present invention include fatty acid amides (amide waxes) synthesized from vegetable oil fatty acids and amines; fatty acid esters, polyethers, and sulfated substances. Surfactant-based oils, higher alcohol sulfates, etc .; polycarboxylic acid esters; polycarboxylic acid amides; urea-modified compounds, but hydrogenated castor oil-based ones called castor oil wax, and polyethylene are oxidized. It does not include polyethylene oxide-based waxes that have a polar group introduced.

(F) Commercially available organic shakers include BYK (registered trademark) -R606, BYK (registered trademark) -405, BYK (registered trademark) -R605, BYK (registered trademark) -R607, BYK (registered trademark). -410, BYK®-411, BYK®-415, BYK®-430, BYK®-431, BYK®-7410ET, BYK®-7411ES (The above is manufactured by Big Chemie Japan), Taren 1450, Taren 2000, Taren 2200A, Taren 7200-20, Taren 8200-20, Taren 8300-20, Taren 8700-20, Taren BA-600, Fronon SH-290, Fronon. Examples thereof include SH-295S, Fronon SH-350, Fronon HR-2, and Fronon HR-4AF (all manufactured by Kyoeisha Chemical Co., Ltd.).

The amount of the organic rocking agent (F) in the curable composition of the present invention is 0.01 part by mass or more and 15 parts by mass or less with respect to 100 parts by mass (solid content) of (E) hydrophilic silica, preferably 0. It is 0.05 parts by mass or more and 10 parts by mass or less.

The amount of the (F) organic rocking agent in the curable composition of the present invention is 0.05 parts by mass or more, preferably 0.1 parts by mass or more, based on 2 parts by mass of the (D) silicone compound. ..

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

[(G) Antioxidant]
It is preferable that the curable composition of the present invention contains (G) an antioxidant. The antioxidant (G) improves the adhesion between the base material and the curable composition by suppressing the oxidation of copper on the copper-clad substrate (base material).

(G) Antioxidants include hindered phenol compounds such as 3- (N-salicyloyl) amino-1,2,4-triazole, sulfur-based antioxidants such as zinc salt of 2-mercaptobenzimidazole, and triphenyl. Phosphite and other phosphorus-based antioxidants, di-tert-butyldiphenylamine and other aromatic amine-based antioxidants, melamine, benzotriazole, triltriazole and other heteroatomic compounds containing nitrogen as heteroatoms (sulfur-based antioxidants) ) Etc. can be mentioned. Of these, melamine is preferable.

The amount of the antioxidant (G) blended is 0.1 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass (solid content) of the (A) alkali-soluble resin in the curable composition of the present invention, which is 0. It is preferably 5.5 parts by mass or more and 2 parts by mass or less.

[Other ingredients]
Further, it is preferable to add a photopolymerizable polyfunctional monomer to the curable composition of the present invention. The photopolymerizable polyfunctional monomer is a compound having two or more ethylenically unsaturated groups in one molecule, and is active ((A) when the alkali-soluble resin contains an ethylenically unsaturated group). It is used to help photocuring the (A) alkali-soluble resin by irradiation with energy rays and to photocuring the curable composition.

Examples of the compound used as the photopolymerizable polyfunctional monomer include commonly known polyester (meth) acrylate, polyether (meth) acrylate, urethane (meth) acrylate, carbonate (meth) acrylate, and epoxy (meth) acrylate. Can be mentioned. Specifically, polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, tris-hydroxyethyl isocyanurate, or ethyleoxyside adducts, propylene oxide adducts, or ε-caprolactone adducts thereof, etc. Polyvalent acrylates; phenoxy acrylates, bisphenol A diacrylates, and polyvalent acrylates such as ethylene oxide adducts or propylene oxide adducts of these phenols; glycerin diglycidyl ether, glycerin triglycidyl ether, trimethyl propantri. Polyvalent acrylates of glycidyl ethers such as glycidyl ethers and triglycidyl isocyanurates; not limited to the above, polyols such as polyether polyols, polycarbonate diols, hydroxyl group terminal polybutadienes, polyester polyols are directly acrylated, or urethanes are made via diisocyanates. Examples thereof include acrylated acrylates and melamine acrylates, and at least one of each methacrylate corresponding to the acrylate.

The photopolymerizable polyfunctional monomer is contained in the curable composition of the present invention in a range of 3 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass (solid content) of the alkali-soluble resin (A), preferably 10 parts by mass. It is blended in the range of 20 parts by mass or less.

The curable composition of the present invention preferably further contains a curing catalyst such as dicyandiamide, boron trifluoride-amine catalyst, or organic acid hydrazide. The amount of the curing catalyst in the curable composition of the present invention is in the range of 5 parts by mass or less, preferably 0.1 parts by mass or more and 2 parts by mass or less, based on 100 parts by mass (solid content) of the (A) alkali-soluble resin. Is added in.

Further, a coloring pigment, a dye or the like may be added to the curable composition of the present invention for the purpose of coloring. As the coloring pigments, dyes and the like, known and commonly used dyes represented by color indexes can be used. For example, 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 Violet 19, 23, 29, 32, 36, 38, 42, Solvent Violet 13, 36, Pigment Brown 23, 25, Pigment Black 1, 7, and the like can be mentioned. These coloring pigments, dyes and the like are in an amount in the range of 0.01 parts by mass or more and 5 parts by mass or less, preferably in a range of 0.1 parts by mass or more and 3 parts by mass or less, with respect to 100 parts by mass of the curable composition. Can be added in quantity.

Further, if necessary, known and conventional polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, pyrogallol, and phenothiazine, photopolymerization sensitizers, photostabilizers, dispersants, flame retardants, and flame retardant aids. Known and commonly used additives such as, etc. can be blended.

Further, the curable composition of the present invention may contain an organic solvent used for adjusting the viscosity. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methylcellosolve, butyl cellosolve, carbitol, methylcarbitol, butylcarbitol and propylene glycol. Glycol ethers such as 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, butyl carbi Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha are used. can do. 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 in the form of a dry film obtained by applying and drying on a carrier film (support). When forming a dry film, the curable composition of the present invention is diluted with the above organic solvent to adjust the viscosity to an appropriate level, and a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer coater, etc. It can be applied to a carrier film to a uniform thickness with a gravure coater, a spray coater, or the like, and usually dried at a temperature of 50 to 130 ° C. for 1 to 30 minutes to obtain a dry coating film. The coating film thickness is not particularly limited, but is generally selected as appropriate in the range of 0.1 to 100 μm, preferably 0.5 to 50 μm after drying.

As the carrier film, a plastic film is used, and it is preferable to use a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, and a plastic film such as a polystyrene film. The thickness of the carrier film is not particularly limited, but is generally selected as appropriate in 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 further laminate a peelable cover film on the surface of the coating film for the purpose of preventing dust from adhering to the surface of the coating 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, and when the cover film is peeled off, the adhesive force between the coating film and the cover film can be used. However, it may be smaller than the adhesive strength between the coating film and the carrier film.

Further, after adjusting the viscosity of the curable composition of the present invention to a viscosity suitable for the coating method using the above organic solvent, a dip coating method, a flow coating method, a roll coating method, a bar coater method, and screen printing are performed on the substrate. Tuck-free dry coating by applying by a method such as a method, a curtain coating method, a die coater method, etc., and volatilizing and drying (temporarily drying) the organic solvent contained in the composition at a temperature of about 50 ° C to 90 ° C. A film can be formed. Further, in the case of a dry film in which the curable composition of the present invention is applied onto a carrier film, dried and wound as a film, the coating film of the curable composition is brought into contact with the substrate by a laminator or the like. A layer of a coating film can be formed on the base material by peeling off the carrier film after the film is attached to the base material.

A cured product can be obtained by, for example, photocuring these coating films by irradiation with active energy rays, or by heating to a temperature of 100 ° C. to 250 ° C. and thermosetting them.

As the base material, in addition to a pre-circuit-formed printed wiring board and flexible printed wiring board, paper + phenol resin, paper + epoxy resin, paper + glass cloth + epoxy resin, glass non-woven fabric + epoxy resin, glass woven cloth + Examples thereof include copper-clad laminates such as epoxy resin, glass fiber + polyimide resin.

The volatile drying performed after applying the curable composition of the present invention uses a hot air circulation type drying oven, an IR furnace, a hot plate, a convection oven, or the like equipped with an air heating type heat source using steam, and hot air in the dryer. Can be carried out by using a method of countercurrent contact and a method of spraying the support from a nozzle.

The exposure machine used for irradiating active energy rays may be a device equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc., and irradiates ultraviolet rays in the range of 350 to 450 nm. , A direct drawing device (for example, a direct imaging device that directly irradiates an active energy ray with CAD data from a computer and draws an image) can also be used. As the light source of the direct drawing machine, light having a maximum wavelength in the range of 350 to 410 nm may be used. The amount of exposure for image formation varies depending on the film thickness and the like, but can be generally in the range of 20 to 1000 mJ / cm ² , preferably 20 to 800 mJ / cm ² .

The developing method can be a dipping method, a shower method, a spray method, a brush method, etc., and the developing solution is potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, etc. , Ammonia, amines and other alkaline aqueous solutions can be used.

As described above, the dry film and the cured product obtained from the curable composition of the present invention are excellent in heat resistance, rigidity, adhesion to a substrate, and insulating property, and thus can be applied to various applications. , There are no particular restrictions on the application target. For example, it can be used for making etching resists, solder resists, marking resists, etc. for printed wiring boards, and among them, it is preferably used as a solder resist that requires high heat resistance because it has improved solderability. Can be done.

<Electronic components using a cured product of a curable composition as an insulating cured film>
When a cured product of a curable composition having a pattern printed on the substrate is used as a solder resist, it is heated in a soldering step for mounting parts. Soldering may be performed by hand soldering, flow soldering, reflow soldering, or the like. For example, in the case of reflow soldering, preheating at 100 ° C. to 140 ° C. for 1 to 4 hours is required. After that, it is subjected to a reflow process in which heating at 240 to 280 ° C. for about 5 to 20 seconds is repeated a plurality of times (for example, 2 to 4 times) to heat and melt the solder, and after cooling, parts are mounted as necessary and electronic. The part is completed.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. In the following, unless otherwise specified, "parts" shall mean parts by mass.

(Synthesis of alkali-soluble resin)
[Synthesis Example 1]
After dissolving 380 parts of bisphenol F type epoxy resin (epoxy equivalent 950 g / eq, softening point 85 ° C.) and 925 parts of epichlorohydrin in 462.5 parts of dimethyl sulfoxide, 98.5% NaOH 60.9 parts at 70 ° C. under stirring. It was added over 100 minutes. After the addition, the reaction was further carried out at 70 ° C. for 3 hours. After completion of the reaction, 250 parts of water was added and washed with water. After oil-water separation, most of dimethyl sulfoxide and excess unreacted epichlorohydrin were distilled and recovered from the oil layer under reduced pressure, and the reaction product containing residual by-salt and dimethyl sulfoxide was dissolved in 750 parts of methyl isobutyl ketone, and further 30% NaOH10 Parts were added and reacted at 70 ° C. for 1 hour. After completion of the reaction, washing with 200 parts of water was carried out twice. After oil-water separation, methyl isobutyl ketone was distilled and recovered from the oil layer to obtain an epoxy resin (a) having an epoxy equivalent of 310 g / eq and a softening point of 69 ° C. The obtained epoxy resin (a) was obtained by epoxidizing about 5 out of 6.2 alcoholic hydroxyl groups in the starting material bisphenol F type epoxy resin, calculated from the epoxy equivalent. 310 parts of the epoxy resin (a) and 282 parts of carbitol acetate were placed in a flask and heated and stirred at 90 ° C. to dissolve them. The obtained solution was once cooled to 60 ° C., 72 parts (1 mol) of acrylic acid, 0.5 part of methylhydroquinone and 2 parts of triphenylphosphine were added, heated to 100 ° C., reacted for about 60 hours, and the acid value was increased. Obtained a reaction product of 0.2 mgKOH / g. 140 parts (0.92 mol) of tetrahydrophthalic anhydride was added thereto, and the mixture was heated to 90 ° C. and reacted to obtain a photosensitive carboxyl group-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 content acid value (mgKOH / g) of 100.

[Synthesis Example 2]
Cresol novolac type epoxy resin (manufactured by Dainippon Ink and Chemicals Co., Ltd., registered trademark "Epiclon" N-695, epoxy equivalent: 220) 220 parts are placed in a four-necked flask equipped with a stirrer and a reflux condenser, and calvi 214 parts of tall acetate was added and dissolved by heating. Next, 0.1 part of hydroquinone as a polymerization inhibitor and 2.0 parts of dimethylbenzylamine as a reaction catalyst were added. The mixture was heated to 95-105 ° C., 72 parts of acrylic acid was gradually added dropwise, and the mixture was reacted for 16 hours. The reaction product was cooled to 80-90 ° C., 106 parts of tetrahydrophthalic anhydride was added, and the mixture was reacted for 8 hours, cooled, and then taken out.
The photosensitive resin having both an ethylenically unsaturated bond and a carboxyl group thus obtained had a non-volatile content of 65%, a solid acid value of 85 mgKOH / g, and a weight average molecular weight of Mw of about 3,500. Hereinafter, this resin solution is referred to as varnish (A-2).
The weight average molecular weight of the obtained resin was measured by high performance liquid chromatography in which three pumps LC-804, KF-803, and KF-802 manufactured by Shimadzu Corporation were connected.

<1. Preparation of curable compositions of Examples 1-9 and Comparative Examples 1-3>
The resin solution of the synthetic example and each material shown in Table 1 were mixed, premixed with a stirrer, and then kneaded with a three-roll mill to prepare a curable composition. In Table 1, (A-1) to (A-3) show the mass parts of each resin solution containing a solvent.

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

<2. Evaluation of repellent / leveling property of curable composition on substrate>
Using a screen plate (Tetron 100 mesh) on a copper-clad substrate (base material) whose surface has been roughened by chemical polishing treatment <1. Each of the curable compositions prepared in Preparation of Curable Compositions of Examples 1 to 9 and Comparative Examples 1 to 3> was printed on the entire surface of the copper-clad substrate so as to have a film thickness of 10 μm.

The coating film immediately after printing was visually observed to confirm the presence or absence of repelling of the curable composition and the leveling state (smoothness). Next, the printed circuit board was dried at 80 ° C. for 30 minutes, returned to room temperature, and the state of the coating film after drying was visually confirmed in the same manner. (Although it is visually confirmed in this embodiment, if it is difficult to make a visual judgment, a surface roughness measuring machine (surf coder: manufactured by Kosaka Research Institute Co., Ltd.) or a shape measuring laser microscope (VK) -X-100 / manufactured by KEYENCE) may be used to observe the surface roughness.)
The evaluation criteria are as follows.

◯: No cissing, no mesh trace Δ: Repelling and no mesh trace, or no cissing and mesh trace ×: Repelling and mesh trace

<3. Evaluation of flux repellent>
Using the screen version (Tetron 100 mesh) <1. Preparation of curable compositions of Examples 1 to 4 and Comparative Examples 1 to 4>, each of the curable compositions prepared in the above, the surface of each curable composition was roughened by a chemical polishing treatment to have an outer diameter of 150 × 95 mm and a thickness of 1.6 mm. FR-4, 35 μm thick copper-clad laminate was printed on the entire surface so as to have a film thickness of 10 μm.

After drying at 80 ° C. for 30 minutes, it was exposed at 600 mJ / cm ² using an exposure mask with a size of 95 × 150 mm for pattern formation, and developed with alkali (1% Na ₂ O ₃ aq, 30 ° C., 60 seconds). ), And after thermosetting at 150 ° C./60 minutes, post-UV treatment of 1000 mJ / cm ² was performed.

The FR-4 substrate (base material) on which the cured product of the curable composition is fixed is subjected to electroless Sn plating treatment (Sn: 1.1 μm / Tsukada Riken Kogyo Co., Ltd.), and a reflow step (265 ° C.) is performed. It is repeated from 1 to 3 times, and the cured product of the curable composition is fixed at each stage after the electroless Sn plating treatment, before the reflow step, after the reflow step once, after the reflow step 2 times, and after the reflow step 3 times. A wet tension test was carried out on the FR-4 substrate.

The wetting tension test is performed based on JIS K6768, and as the wet tension test mixed solution, "wet tension test mixed solution No. 60.0" is used once after the electroless Sn plating process and before the reflow process. After that, "Mixed solution for wet tension test NO.38.0", after 2 reflow steps, "Mixed solution for wet tension test NO.36.0", and after 3 times of reflow step, "Mixing for wet tension test" Liquid No. 34.0 ”was used respectively. Both wet tension test mixed solutions are manufactured by Fuji Film Wako Junyaku Co., Ltd. The NO. Of each mixed solution. Indicates the surface tension (unit: mN / m) of the mixed solution.

Specifically, in the wetting tension test, the substrate was traced with a cotton swab with a mixed solution for the wetting tension test, and the state of the liquid film after 2 seconds was observed. Then, it was judged that the liquid film was wet when the liquid film did not break and kept the state when it was applied for 2 seconds or more.

No. of the mixed solution for wetting tension test. The larger the value of, the more difficult it is to get wet. Therefore, the wetting tension test is a test for evaluating flux repelling (flux wetting property).

In Table 1, the evaluation criteria are as follows.

◯: After the electroless Sn plating treatment, it is judged to be wet (no cissing) at all stages from before the reflow process to after 3 times of the reflow process.

X: After electroless Sn plating treatment Before the reflow process to after 3 times of the reflow process, it may be judged that the product is not wet (repellent) even once.

* 1: Cyclomer P (ACA) Z250 (unsaturated group-containing carboxyl group-containing copolymer resin solution with a solid content of 45 wt%, manufactured by Daicel Chemical Industries, Ltd.)
* 2: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Omnirad TPO H: manufactured by IGM Resins BV)
* 3: 2-Dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholine-4-yl-phenyl) -butane-1-one (Omnirad 379: manufactured by IGM Resins BV)
* 4: Bisphenol A type epoxy resin (JER (registered trademark) -834: manufactured by Mitsubishi Chemical Corporation)
* 5: Trichloroisocyanuric acid (TEPIC-HP: manufactured by Nissan Chemical Industries, Ltd.)
* 6: Polyester-modified polydimethylsiloxane (BYK (registered trademark) -313: manufactured by Big Chemie Japan)
* 7: Polyether-modified polydimethylsiloxane (BYK (registered trademark) -300: manufactured by Big Chemie Japan)
* 8: Spherical silica (D50 = 0.6 μm) (SFP-130MC: manufactured by Denki Kagaku Kogyo Co., Ltd.)
* 9: Spherical silica (D50 = 0.4 μm) (SFP-20M: manufactured by Denki Kagaku Kogyo Co., Ltd.)
* 10: Polyhydroxycarboxylic acid ester (BYK (registered trademark) -R 606: manufactured by Big Chemie Japan Co., Ltd.)
* 11: Melamine (Melamine: manufactured by Nissan Chemical Industries, Ltd.)
* 12: Spherical silica with methacrylic silane treatment on the surface (1.5 μm SM-C4: manufactured by Admatex)
* 13: Dipentaerythritol hexaacrylate (DPHA: manufactured by Nippon Kayaku Co., Ltd.)
* 14: Dicyandiamide (DICY7: manufactured by Mitsubishi Chemical Corporation)
* 15: Blue pigment (Firstgen Blue 5380: manufactured by DIC Corporation), Table 1 shows the mass part of the solid content.
* 16: Yellow pigment (Cromophtal (registered trademark) Yellow S1515: manufactured by BASF), Table 1 shows the mass part of the solid content.
* 17: Dipropylene glycol methyl ether (Dowanol (registered trademark) DPM: Dow Chemical Japan, Ltd.)

As shown in the examples of Table 1, when (D) a silicone compound, (E) hydrophilic silica and (F) an organic rocking agent are blended, the curable composition of the present invention on a copper-clad substrate (base material) is formed. The wettability of the compound was maintained, the leveling property was also good, and (E) hydrophilic silica did not aggregate or precipitate. Further, even when the wet tension test mixed solution is applied onto the substrate on which the cured product of the curable composition of the present invention is fixed, the wet tension test mixed solution does not repel on the cured product. The wettability of the mixed solution for the wetting tension test with respect to the cured product was maintained.

On the other hand, in Comparative Example 1 in which the surface of silica is treated with a hydrophobic treatment, a wetting tension test is performed on a substrate on which a cured product of the curable composition is fixed even if (F) an organic rocking agent is blended. It was considered that the wettability of the mixed solution for use was lowered and the solderability was lowered. Further, in Comparative Example 2 containing (F) an organic rocking agent, even if (D) a silicone compound and (E) hydrophilic silica were blended, the cured product of the curable composition was wetted with respect to the fixed substrate. It was considered that the wettability of the tension test mixture was reduced and the solderability was reduced. Further, in Comparative Example 3 in which the (D) silicone compound was not contained, the wettability of the curable composition with respect to the copper-clad substrate (base material) was insufficient, or the leveling property was deteriorated.

Claims

(A) Alkali-soluble resin and
(B) Photopolymerization initiator and
(C) Epoxy resin and
(D) Silicone compound and
(E) Hydrophilic silica and
(F) Organic shaker and
A curable composition comprising.
(E) The curable composition according to claim 1, wherein the median diameter D50 of the hydrophilic silica is 0.2 μm or more and 2.0 μm or less.
The amount of (F) organic rocking agent is 0.01 part by mass or more and 15 parts by mass or less with respect to 100 parts by mass of (E) hydrophilic silica, and 0. The curable composition according to claim 1 or 2, wherein the amount is 05 parts by mass or more.
(G) The curable composition according to any one of claims 1 to 3, further comprising an antioxidant.
A dry film obtained by applying the curable composition according to any one of claims 1 to 4 on a carrier film and drying it.
A dry coating film obtained by applying and drying the curable composition according to any one of claims 1 to 4 on a substrate, or the curable composition is applied and dried on a carrier film. A cured product obtained by curing a coating film obtained by laminating a dry film obtained by the process on a substrate.
An electronic component comprising the cured product according to claim 6.