CN108141964B

CN108141964B - Curable composition for inkjet, cured coating film using same, and printed wiring board

Info

Publication number: CN108141964B
Application number: CN201680056194.4A
Authority: CN
Inventors: 吉川里奈; 志村优之; 松本博史
Original assignee: Taiyo Ink Mfg Co Ltd
Current assignee: Taiyo Holdings Co Ltd
Priority date: 2015-09-30
Filing date: 2016-07-26
Publication date: 2020-08-11
Anticipated expiration: 2036-07-26
Also published as: KR20180063172A; WO2017056663A1; CN108141964A; TWI705113B; TW201726841A

Abstract

Providing: the curable composition for inkjet printing has good adhesion to a substrate, high hardness after curing, and low viscosity suitable for inkjet printing in addition to various characteristics such as soldering heat resistance and gold plating resistance, a cured coating film obtained by curing the curable composition, and a printed wiring board having the cured coating film on a substrate. A curable composition for inkjet, comprising: (A) a urethane (meth) acrylate resin having 5 or more and 12 or less functions; and (B) a photopolymerization initiator.

Description

Curable composition for inkjet, cured coating film using same, and printed wiring board

Technical Field

The present invention relates to a curable composition for inkjet (hereinafter, also simply referred to as "curable composition") used for printing by inkjet system, a cured coating film using the same, and a printed wiring board.

Background

In recent years, as a method for forming a coating film of a resist, a solder resist, a symbol mark, or the like on a printed wiring board, a method of printing by an ink jet method has attracted attention from the viewpoint of enabling easy implementation (patent document 1).

Documents of the prior art

Patent document

Patent document 1: international publication No. 2004/099272

Disclosure of Invention

Problems to be solved by the invention

On the other hand, various curable compositions for printed wiring boards, such as resist inks and marking inks, formed on printed wiring boards are required to have good adhesion to conductive layers such as conductive circuit metals and substrates such as plastic substrates, to have high hardness after curing, and to have solder heat resistance and gold plating resistance under more severe conditions.

However, it is difficult in design to satisfy all of the required performances described above while satisfying the printability (coatability) of the ink jet system with respect to the composition used in the printing of the ink jet system.

Accordingly, an object of the present invention is to provide: a curable composition for inkjet which has good adhesion to a substrate, high hardness after curing, and low viscosity suitable for inkjet printing, in addition to various characteristics such as solder heat resistance and gold plating resistance; cured coating films and printed wiring boards using the same.

Means for solving the problems

The present inventors have conducted intensive studies and, as a result, have found that: the above problems can be solved by a curable composition comprising a urethane (meth) acrylate resin having a predetermined functional number and a photopolymerization initiator, and the present invention has been completed.

That is, the curable composition for inkjet according to the present invention is characterized by comprising:

(A) a urethane (meth) acrylate resin having 5 or more and 12 or less functions; and the combination of (a) and (b),

(B) a photopolymerization initiator.

In the curable composition of the present invention, the viscosity of the urethane (meth) acrylate resin (a) at 25 ℃ is preferably 1000 to 20000mPa · s. In addition, the curable composition of the present invention preferably further comprises: (C) the thermosetting compound having at least 1 thermally reactive functional group (excluding the epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group) preferably contains, as the (C) thermosetting compound (excluding the epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group): a1 st thermosetting compound having at least 1 (meth) acryloyl group and at least 1 thermoreactive functional group; and a2 nd thermosetting compound having at least 2 thermally reactive functional groups. Further, the curable composition of the present invention preferably further comprises: (D) an epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group, and the aforementioned (D) epoxy (meth) acrylate resin is preferably a bisphenol type epoxy (meth) acrylate resin. Further, the curable composition of the present invention preferably further comprises: (E) the 2-functional (meth) acrylate compound, and the (E) 2-functional (meth) acrylate compound are preferably compounds having an alkylene chain having 4 to 12 carbon atoms. Further, the viscosity at50 ℃ of the curable composition of the present invention is suitably 50 mPas or less.

The cured coating film of the present invention is obtained by curing the curable composition for inkjet according to the present invention.

The printed wiring board of the present invention is characterized by having the cured coating film of the present invention on a substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to realize: a curable composition for inkjet which has good adhesion to a substrate, high hardness after curing, and low viscosity suitable for inkjet printing, in addition to various characteristics such as solder heat resistance and gold plating resistance; a cured coating film using the same; and, a printed circuit board.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail.

In the present invention, the curable composition means a composition that is cured by light, heat, or both. In addition, the term (meth) acrylate refers to a general term of acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

The curable composition for inkjet according to the present invention is characterized by comprising: (A) a urethane (meth) acrylate resin having 5 or more and 12 or less functions; and (B) a photopolymerization initiator.

[ (A) urethane (meth) acrylate resin having 5 or more and 12 or less functions ]

(A) The urethane (meth) acrylate resin refers to a compound having a plurality of urethane bonds and a plurality of (meth) acryloyl groups. Examples of the 5-functional urethane (meth) acrylate resin that can be used in the present invention include DM850 available from DOUBLE BOND CHEMICAL Co., Ltd, and HITALOID 7903-1 available from Hitachi CHEMICAL Co., Ltd. Examples of the 6-functional urethane (meth) acrylate resin include U-6LPA manufactured by Nikamura CHEMICAL industries, CN975 manufactured by UA-1100H, SATOMER, EBECRYL220 manufactured by DAICEL ALLNEX, KRM8200AE, EBECRYL 8254, EBECRYL 8301R, DM527, DM528, DM571, DM576, DM776, DM87A, DM88A manufactured by DOUBLE ND CHEMICAL, HITALOID 7902-1 manufactured by Hitachi Kasei corporation, TA24-195H, and the like.

Further, examples of the 9-functional urethane (meth) acrylate resin include KRM8904 manufactured by DAICEL ALLNEX, HITALOID 7903-3 manufactured by Hitachi chemical Co., Ltd., HITALOID 7903-B, and the like. Further, examples of the 10-functional urethane (meth) acrylate resin include KRM8452 manufactured by DAICEL ALLNEX, and DM588 manufactured by DOUBLE BOND CHEMICAL Co. Further, examples of the 12-functional urethane (meth) acrylate resin include DM5812 manufactured by DOUBLE BOND CHEMICAL Co., Ltd, and HITALOID 7903-4 manufactured by Hitachi CHEMICAL Co., Ltd. These urethane (meth) acrylate resins may be used alone or in the form of a mixture of 2 or more.

The viscosity of the urethane (meth) acrylate resin (A) at 25 ℃ is preferably 1000 to 20000 mPas, particularly preferably 1000 to 10000 mPas, in order to keep the viscosity of the entire composition low. By using the urethane (meth) acrylate resin (a) having a relatively low viscosity, the viscosity of the entire composition is suppressed to be low, and the ejection property and stability at the time of ink jet printing are improved. The use of a 5-or more-functional urethane (meth) acrylate resin improves heat resistance, and the use of a 12-or less-functional urethane (meth) acrylate resin can impart flexibility to the formed coating film and improve properties such as adhesion. More preferably 8 or less functional groups, and still more preferably 6 or less functional groups.

The amount of the urethane (meth) acrylate resin (a) is preferably 0.5 to 60 parts by mass, more preferably 1.5 to 55 parts by mass, per 100 parts by mass of the curable composition. By setting the amount of the urethane (meth) acrylate resin to 0.5 parts by mass or more, good solder heat resistance and gold plating resistance can be ensured. Further, by setting the amount of the urethane (meth) acrylate resin to 60 parts by mass or less, the viscosity of the curable composition can be suppressed to be low, and the ejection property and stability at the time of inkjet printing can be favorably ensured.

[ (B) photopolymerization initiator ]

The photopolymerization initiator (B) is not particularly limited, and for example, a photo radical polymerization initiator can be used. As the photo radical polymerization initiator, any photo radical polymerization initiator can be used as long as it is a compound that generates radicals by light, laser, electron beam, or the like and initiates a radical polymerization reaction.

Examples of the photo radical polymerization initiator include: benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and the like; acetophenone such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one, acetophenone such as acetophenone, 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-2-phenylacetophenone, 1-dichloroacetophenone and the like; aminoacetophenones such as 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, and N, N-dimethylaminoacetophenone; anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone and 1-chloroanthraquinone; thioxanthones such as 2, 4-dimethylthioxanthone, 2, 4-diethylthioxanthone, 2-chlorothioxanthone and 2, 4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzil dimethyl ketal; 2,4, 5-triarylimidazole dimer; riboflavin tetrabutyrate; thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole and 2-mercaptobenzothiazole; organic halogen compounds such as 2,4, 6-tris-s-triazine, 2,2, 2-tribromoethanol, tribromomethylphenyl sulfone and the like; benzophenones such as benzophenone and 4, 4' -bisdiethylaminobenzophenone, or xanthones; acylphosphine oxide systems such as 2,4, 6-trimethylbenzoyldiphenylphosphine oxide and bis (2,4, 6-trimethylbenzoyl) -phenylphosphine oxide.

These known and commonly used photopolymerization initiators may be used alone or in the form of a mixture of 2 or more kinds, and further, a photoinitiator aid such as ethyl N, N-dimethylaminobenzoate, isoamyl N, N-dimethylaminobenzoate, amyl-4-dimethylaminobenzoate, triethylamine, triethanolamine or other tertiary amines may be added.

Further, in order to promote the photoreaction, a titanocene compound such as IRGACURE 784 (manufactured by basf japan) which absorbs in the visible light region may be added. The photopolymerization initiator and the photoinitiator aid are not particularly limited, and may be used alone or in combination of two or more.

Examples of commercially available products include IRGACURE 261, 184, 369, 651, 500, 819, 907, 784, 2959, IRGACURE 1116, 1173, IRGACURE TPO (trade name of BASF Japan K.K.), ESACUREKIP150, KIP65LT, KIP100F, KT37, KT55, KTO46, KIP75/B, ONE (trade name of FRETELLLI LAMBERTI Co., Ltd.).

(B) The blending ratio of the photopolymerization initiator is preferably in the range of 1 to 25 parts by mass, more preferably in the range of 5 to 20 parts by mass, and particularly preferably in the range of 5 to 15 parts by mass, based on 100 parts by mass of the curable composition of the present invention. When the blending ratio of the photopolymerization initiator (B) is in the above range, appropriate photocurability can be obtained.

[ (C) thermosetting Compound having at least 1 thermally reactive functional group (in addition to epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group) ]

The heat-reactive functional group of the heat-curable compound (C) is a known and commonly used heat-curable functional group selected from at least 1 kind of functional groups selected from the group consisting of a hydroxyl group, a carboxyl group, an isocyanate group, an amino group, an imine group, an epoxy group, an oxetanyl group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, and an oxazoline group, a cyclic (thio) ether group, a (cyclo) carbonate group, a episulfide group, and a polyoxazolinyl group, and more preferably at least 1 kind of functional groups selected from the group consisting of a hydroxyl group, a carboxyl group, an isocyanate group, an amino group, an imine group, an epoxy group, an oxetanyl group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl.

For (C) the thermally reactive compound, it preferably has at least 1 (meth) acryloyl group in addition to at least 1 thermally reactive functional group. Generally, a compound having a monofunctional heat-reactive functional group has a problem in that it has a low molecular weight and volatilizes as a result of a thermal reaction during heat curing, but since it has a (meth) acryloyl group, it polymerizes during precuring by light in inkjet printing, and does not volatilize during main curing by heat, and good characteristics can be obtained.

In the present invention, it is particularly preferable to use a1 st thermosetting compound having at least 1 (meth) acryloyl group and at least 1 thermoreactive functional group in combination with a2 nd thermosetting compound having at least 2 thermoreactive functional groups as the (C) thermosetting compound. This can further improve the welding heat resistance.

Specific examples of the hydroxyl group in the thermally reactive functional group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, and 2-hydroxypropyl (meth) acrylate, and commercially available products include: LIGHTESTER HO, LIGHT ESTER HOP, LIGHT ESTER HOA (trade name of Kyoeisha chemical Co., Ltd.).

Specific examples of the thermosetting compound in which the thermally reactive functional group is a carboxyl group include acrylic acid, methacrylic acid, acrylic acid dimer, 2-methacryloyloxyethyl succinate, methacryloyloxyethyl hexahydrophthalate, monohydroxyethyl phthalate and the like, and commercially available products include: LIGHT ESTER HO-MS, LIGHT ESTERHO-HH (trade name of Kyoeisha chemical Co., Ltd.), ARNIX M-5400 (trade name of Toyo Synthesis chemical Co., Ltd.), and the like.

Specific examples of the thermosetting compound in which the thermally reactive functional group is an isocyanate group include 2-methacryloyloxyethyl isocyanate (for example, product name, MOI manufactured by SHOWA DENKO K.K.).

Specific examples of the thermosetting compound in which the thermally reactive functional group is an amino group include acrylamide, N-dimethylaminoethyl acrylate, N-dimethylaminoethyl methacrylate, N-diethylaminoethyl acrylate, and N, N-diethylaminoethyl methacrylate.

Specific examples of the thermosetting compound in which the thermally reactive functional group is an epoxy group include glycidyl methacrylate, a (meth) acryloyl group-containing alicyclic epoxy resin, a (meth) acryloyl group-containing bisphenol a type epoxy resin, and the like. Examples of commercially available (meth) acryloyl group-containing alicyclic epoxy resins include CYCLOMER M100, CYCLOMER a200, and CYCLOMER 2000 (trade names of DAICEL, inc.). Commercially available products of bisphenol A type epoxy resins containing a (meth) acryloyl group include NK OLIGO EA-1010N, EA-1010LC and EA-1010NT (trade name of NONSHONGWA CHEMICAL INDUSTRIAL CO., LTD.).

Specific examples of the thermosetting compound in which the thermally reactive functional group is an oxetanyl group include oxetane (meth) acrylate and the like, and examples of commercially available products include OXE-10 and OXE-30 (trade name manufactured by Osaka organic Chemicals Co., Ltd.).

Specific examples of the thermosetting compound in which the thermally reactive functional group is a mercapto group include ethyl acrylate thioester, ethyl methacrylate thioester, biphenyl acrylate thioester, biphenyl methacrylate thioester, nitrophenyl acrylate thioester, nitrophenyl methacrylate thioester, triphenylmethyl acrylate thioester, triphenylmethyl methacrylate thioester, triacrylate of 1, 2-bis [ (2-mercaptoethyl) thio ] -3-mercaptopropane, 2- (mercaptomethyl) -methyl 2-acrylate, and 2- [ (2-mercaptoethyl) thio ] ethyl methacrylate.

Specific examples of the thermosetting compound in which the thermally reactive functional group is a methoxymethyl group include methoxymethyl acrylate, methoxymethyl methacrylate, dimethoxymethyl acrylate, dimethoxymethyl methacrylate, and the like, and commercially available products include: NIKALAC MX-302 (trade name of acrylic acid-modified alkylated melamine, Tri, Kagaku Co., Ltd.), and the like.

Specific examples of the thermosetting compound in which the thermally reactive functional group is methoxyethyl include 1-methoxyethyl acrylate, 1-methoxyethyl methacrylate, 2-methoxyethyl acrylate, 2-methoxyethyl methacrylate, 1-methoxyethyl acrylate, and 1, 1-methoxyethyl methacrylate.

Specific examples of the thermosetting compound in which the thermally reactive functional group is ethoxyethyl group include 1-ethoxyethyl acrylate, 1-ethoxyethyl methacrylate, 2-ethoxyethyl acrylate, and 2-ethoxyethyl methacrylate.

Specific examples of the thermosetting compound having an ethoxymethyl group as a thermally reactive functional group include N-ethoxymethacrylamide, ethoxymethyl acrylate, and ethoxymethyl methacrylate.

Specific examples of the thermosetting compound in which the thermally reactive functional group is an oxazoline group include 2-methyl-2- { [3- (4, 5-dihydro-2-oxazolyl) benzoyl ] amino } ethyl ester of 2-acrylic acid, 2-methyl-2- (4, 5-dihydro-2-oxazolyl) ethyl ester of 2-acrylic acid, 3- (4, 5-dihydro-4, 4-dimethyl-2-oxazolyl) propyl ester of 2-acrylic acid, and the like.

As the thermosetting compound having 2 or more thermally reactive functional groups, known thermosetting resins such as melamine resins, benzoguanamine resins, amino resins such as melamine derivatives and benzoguanamine derivatives, blocked isocyanate compounds, cyclic carbonate compounds, thermosetting components having a cyclic (thio) ether group, bismaleimides and carbodiimide resins can be used. From the viewpoint of excellent storage stability, a blocked isocyanate compound is particularly preferable.

The thermosetting compound having a plurality of cyclic (thio) ether groups in the molecule is any of cyclic (thio) ether groups having 3, 4 or 5 membered rings in the molecule or a compound having a plurality of 2 kinds of groups, and examples thereof include a compound having a plurality of epoxy groups in the molecule, that is, a polyfunctional epoxy compound, a compound having a plurality of oxetanyl groups in the molecule, that is, a polyfunctional oxetane compound, a compound having a plurality of thioether groups in the molecule, that is, an episulfide resin, and the like.

Examples of the polyfunctional epoxy compound include: epoxidized vegetable oils such as ADEKACIZER O-130P, ADEKACIZER O-180A, ADEKACIZER D-32 and ADEKACIZER D-55 manufactured by ADEKA corporation; JeR828, JeR834, JeR1001, JeR1004, EPICLON 840, EPICLON 850, EPICLON 1050, EPICLON 2055, EPITOT YD-011, YD-013, YD-127, YD-128, D.E.R.317, D.E.R.331, D.E.R.011, D.E.R.661, SUMI XY ESA-011, ESA-014, ELA-115, ELA-128, A.E.R.330, A.E.R.331, A.E.R.661, A.E.664 and A.E.R.664 of Mitsui Kasei corporation, all of which are bisphenol EPOXY resins (trade names) such as EPOXY resin A.E.R.664; hydroquinone type epoxy resin such as YDC-1312, bisphenol type epoxy resin such as YSLV-80XY, and thioether type epoxy resin such as YSLV-120TE (all manufactured by Tokyo Kasei Co., Ltd.); brominated EPOXY resins such as jERYL903 manufactured by mitsubishi CHEMICAL corporation, EPICLON152 manufactured by DIC corporation, EPICLON 165, EPITOT YDB-400 manufactured by toyokoku CHEMICAL corporation, YDB-500, d.e.r.542 manufactured by DOW CHEMICAL corporation, SUMI EPOXY ESB-400 and ESB-700 manufactured by sumitomo CHEMICAL corporation, a.e.r.711 and a.e.r.714 (trade names in each case); novolac type EPOXY resins such as JeR152, JeR154 manufactured by Mitsubishi CHEMICAL corporation, D.E.N.431 and D.E.N.438 manufactured by DOW CHEMICAL Co., Ltd, EPICLON-730, EPICLON-770, EPICLON-865 manufactured by DIC corporation, EPITOT YDCN-701 and YDCN-704 manufactured by Tokyo Kaisha, EPPN-201, EOCN-1025, EOCN-1020, EOCN-104S, RE-306 manufactured by Nippon Kaisha, EPOMI SUXY ESCN-195X, ESCN-220 manufactured by Sumitomo CHEMICAL industry Co., Ltd, A.E.R.ECN-235 manufactured by Asahi Kaisha CHEMICAL industry Co., Ltd, and ECN-299; bisphenol novolac type epoxy resins such as NC-3000 and NC-3100 manufactured by Nippon chemical Co., Ltd; bisphenol F type epoxy resins such as EPICLON 830 manufactured by DIC, jER807 manufactured by Mitsubishi chemical corporation, EPITOT YDF-170, YDF-175, YDF-2004 manufactured by Tokyo Kaisha, and the like (trade names); hydrogenated bisphenol A type epoxy resins such as EPITOT ST-2004, ST-2007 and ST-3000 (trade name) manufactured by Tokyo chemical Co., Ltd.; glycidyl amine type EPOXY resins such as JeR604 manufactured by Mitsubishi chemical corporation, EPITOT YH-434 manufactured by Tokyo chemical Co., Ltd, and SUMI EPOXY ELM-120 manufactured by Sumitomo chemical industry Co., Ltd; hydantoin type epoxy resins; an alicyclic epoxy resin; trihydroxyphenyl methane type epoxy resins such as YL-933 manufactured by Mitsubishi CHEMICAL corporation, T.E.N. manufactured by DOW CHEMICAL corporation, EPPN-501, EPPN-502, and the like (all trade names); dixylenol-type or diphenol-type epoxy resins such as YL-6056, YX-4000 and YL-6121 (trade names) available from Mitsubishi chemical corporation, or a mixture thereof; bisphenol S type epoxy resins such as EBPS-200 manufactured by Nippon Kabushiki Kaisha, EPX-30 manufactured by ADEKA Kaisha, and EXA-1514 (trade name) manufactured by DIC Kaisha; bisphenol a novolac type epoxy resins such as jER157S (trade name) manufactured by mitsubishi chemical corporation; tetrahydroxyphenylethane-type epoxy resins such as jERYL-931 (trade name) manufactured by Mitsubishi chemical corporation; heterocyclic epoxy resins such as TEPIC (trade name) manufactured by Nissan chemical industries, Ltd; diglycidyl phthalate resin such as BRENMER DGT manufactured by japan fat and oil co; tetraglycidyl xylenol ethane resins such as ZX-1063 manufactured by Tokyo Kabushiki Kaisha; naphthyl group-containing epoxy resins such as ESN-190, ESN-360, HP-4032, EXA-4750 and EXA-4700, manufactured by Nippon Tekko Kaisha, and DIC Kaisha; epoxy resins having a dicyclopentadiene skeleton such as HP-7200 and HP-7200H manufactured by DIC; glycidyl methacrylate copolymer epoxy resins such as CP-50S, CP-50M manufactured by Nippon fat and oil Co., Ltd; further, a copolymerized epoxy resin of cyclohexylmaleimide and glycidyl methacrylate; epoxy-modified polybutadiene rubber derivatives, CTBN-modified epoxy resins (for example, YR-102 and YR-450 available from Tokyo chemical Co., Ltd.), and the like, but are not limited thereto. These epoxy resins may be used alone or in combination of 2 or more. Among them, particularly preferred are novolak type epoxy resins, bixylenol type epoxy resins, biphenol novolak type epoxy resins, naphthalene type epoxy resins, or mixtures thereof.

Examples of the polyfunctional oxetane compound include bis [ (3-methyl-3-oxetanylmethoxy) methyl ] ether, bis [ (3-ethyl-3-oxetanylmethoxy) methyl ] ether, 1, 4-bis [ (3-methyl-3-oxetanylmethoxy) methyl ] benzene, 1, 4-bis [ (3-ethyl-3-oxetanylmethoxy) methyl ] benzene, (3-methyl-3-oxetanylmethoxy) methyl acrylate, (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate, and mixtures thereof, Polyfunctional oxetanes such as oligomers and copolymers thereof, and etherates of oxetanols and hydroxyl group-containing resins such as novolak resins, poly (p-hydroxystyrene), Cardo-type bisphenols, calixarenes, and silsesquioxanes. Further, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate, and the like can be mentioned.

Examples of the compound having a plurality of cyclic sulfide groups in the molecule include bisphenol a type cyclic sulfide resin YL7000 manufactured by mitsubishi chemical corporation. Alternatively, episulfide resins obtained by replacing an oxygen atom of an epoxy group of a novolac epoxy resin with a sulfur atom by the same synthesis method can be used.

Examples of the amino resin such as a melamine derivative and a benzoguanamine derivative include: methylol melamine compounds, methylol benzoguanamine compounds, methylol glycoluril compounds, methylol urea compounds, and the like. Further, the alkoxymethylated melamine compound, alkoxymethylated benzoguanamine compound, alkoxymethylated glycoluril compound and alkoxymethylated urea compound can be obtained by converting the methylol group of each of the methylolmelamine compound, methylolbenzoguanamine compound, methylolglycoluril compound and methylolurea compound into an alkoxymethyl group. The kind of the alkoxymethyl group is not particularly limited, and examples thereof include a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, and a butoxymethyl group. Particularly, a melamine derivative having a formaldehyde concentration of 0.2% by mass or less is preferable, which is excellent for the human body and the environment.

Examples of the commercially available products include CYMEL 300, CYMEL 301, CYMEL 303, CYMEL 370, CYMEL 325, CYMEL 327, CYMEL 701, CYMEL 266, CYMEL 267, CYMEL 238, CYMEL 1141, CYMEL272, CYMEL 202, CYMEL 1156, CYMEL 1158, CYMEL 1123, CYMEL 1170, CYMEL 1174, CYMEL 65, CYMEL 300 (all manufactured by Mitsui CYANAMIDE Co., Ltd.), NIKALAC Mx-750, NIKALAC Mx-032, KANIKALAC Mx-270, NIKAC Mx-280, NIKALAC Mx-290, NIKALAC Mx-706, NIKALAC Mx-708, NIKALAC-40, NIKAC-31, NIKAC-11, NIKAC-30, NIKAC-Mw-750, NIKAC-100, NIKAC-M-390, NIKAC Mx-032, NIKAC-80, NIKAC-M-100, NIKAC-M-390, NIKAC, NIKAM-M-K.

The isocyanate compound and the blocked isocyanate compound are compounds having a plurality of isocyanate groups or blocked isocyanate groups in 1 molecule. Examples of the compound having a plurality of isocyanate groups or blocked isocyanate groups in 1 molecule include polyisocyanate compounds and blocked isocyanate compounds. The blocked isocyanate group is a group in which an isocyanate group is protected by a reaction with a blocking agent and temporarily inactivated, and when heated to a predetermined temperature, the blocking agent is dissociated to generate an isocyanate group. The addition of the polyisocyanate compound or the blocked isocyanate compound confirmed the improvement of curability and toughness of the resulting cured product.

As such a polyisocyanate compound, for example, an aromatic polyisocyanate, an aliphatic polyisocyanate, or an alicyclic polyisocyanate can be used.

Specific examples of the aromatic polyisocyanate include 4, 4' -diphenylmethane diisocyanate, 2, 4-xylylene diisocyanate, 2, 6-xylylene diisocyanate, naphthalene-1, 5-diisocyanate, o-xylylene diisocyanate, m-xylylene diisocyanate, and 2, 4-xylylene diisocyanate dimer.

Specific examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, and the like.

Specific examples of the alicyclic polyisocyanate include bicycloheptane triisocyanate. Further, there may be mentioned an adduct of the above-mentioned isocyanate compounds, a biuret compound and an isocyanurate compound.

As the blocked isocyanate compound, an addition reaction product of an isocyanate compound and an isocyanate blocking agent may be used. Examples of the isocyanate compound capable of reacting with the blocking agent include the polyisocyanate compounds described above.

Examples of the isocyanate blocking agent include phenol blocking agents such as phenol, cresol, xylenol, chlorophenol and ethylphenol; lactam-based blocking agents such as caprolactam, -valerolactam, γ -butyrolactam and β -propiolactam; an active methylene-based blocking agent such as ethyl acetoacetate or acetylacetone; alcohol-based blocking agents such as methanol, ethanol, propanol, butanol, pentanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl ether, methyl glycolate, butyl glycolate, diacetone alcohol, methyl lactate, and ethyl lactate; oxime blocking agents such as formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diacetyl monoxime, and cyclohexane oxime; thiol-based blocking agents such as butyl mercaptan, hexyl mercaptan, tert-butyl mercaptan, thiophenol, methyl thiophenol, and ethyl thiophenol; amide-based blocking agents such as acetamide and benzamide; imide-based capping agents such as succinimide and maleimide; amine-based blocking agents such as dimethylaniline, aniline, butylamine, and dibutylamine; imidazole-based capping agents such as imidazole and 2-ethylimidazole; and imine-based blocking agents such as methylene imine and propylene imine.

The blocked isocyanate compound may be a commercially available product, and examples thereof include SUMIDUR BL-3175, BL-4165, BL-1100, BL-1265, DESMODUR TPLS-2957, TPLS-2062, TPLS-2078, TPLS-2117, DESMOTHERM 2170, DESMOTHER 2265 (both manufactured by Sumitomo-Bayer Urethane Co. Ltd.), CORONATE 2512, CORONATE 2513, CORONATE 2520 (both manufactured by Nippon polyurethane industries, Ltd.), B-830, B-815, B-846, B-870, B-874, and B-882 (both manufactured by Mitsui Katsui Kasei chemical Co., Ltd.), TPA-B80E, 17B-60PX, and E402-B80T (both manufactured by Asahi chemical Co., Ltd.). SuMIDUR BL-3175 and BL-4265 were obtained using methylethyloxime as a blocking agent. Such 1 compound having a plurality of isocyanate groups or blocked isocyanate groups in the molecule may be used alone in 1 kind or in combination with 2 or more kinds.

(C) The compounding ratio of the thermosetting compound is preferably within a range of 10 to 70 parts by mass, and more preferably within a range of 20 to 60 parts by mass, based on 100 parts by mass of the curable composition of the present invention. When the amount of the component (B) is 10 parts by mass or more, sufficient toughness and heat resistance of the coating film can be obtained. On the other hand, if it is 70 parts by mass or less, the decrease in storage stability can be suppressed. (C) The thermosetting compound may be used alone in 1 kind or in combination with 2 or more kinds.

[ (D) epoxy (meth) acrylate resin having at least one (meth) acryloyl group ]

Examples of the epoxy (meth) acrylate resin having at least one (meth) acryloyl group include a bisphenol a type epoxy (meth) acrylate resin, a bisphenol F type epoxy (meth) acrylate resin, a bisphenol E type epoxy (meth) acrylate resin, a cresol novolac type epoxy (meth) acrylate resin, a phenol novolac type epoxy (meth) acrylate resin, an aliphatic epoxy (meth) acrylate, and the like.

Examples of the bisphenol A-type EPOXY (meth) acrylate resin include EBECRYL 600, EBECRYL 605, EBECRYL 648, EBECRYL 3700, EBECRYL 3703 (trade name manufactured by DAICEL ALLNEX Co., Ltd.), EPOXY ESTER EX-0205, EPOXY ESTER 3000A, EPOXY ESTER 3002A (N) (trade name manufactured by TOKARON CHEMICAL CO., LTD), 8026, 8101, 8125, 8197, 8250L M H, 8260, 8355, 8360BR, 8327, 8351 (trade name manufactured by JAPONI U-PICA CORPORATION), HIOL 7851 (trade name manufactured by KARAISO KARIO CO., LTD), BISCOTE #540 (trade name manufactured by KARAZO CORPORATION CO., CN120A 120, CN120C 35120, CN120C 120, CN, NK OLIGO EA-1010N, EA-1010LC, EA-1010NT, EA-1020LC3, EMA-1020 (trade name of Mitsukamura chemical Co., Ltd.).

Examples of the bisphenol F type epoxy (meth) acrylate resin include 8475 and 8476 (trade name of Japan U-PICA Co., Ltd.).

Examples of the cresol novolak type epoxy (meth) acrylate resin include NK OLIGO EA-7120/PGMAC, EA-7140/PGMAC, EA-7420/PGMAC (trade name of Ninghamu chemical Co., Ltd.).

Examples of the phenol novolak type epoxy (meth) acrylate resin include 8400, 8411L H (trade name of Nippon U-PICA Co., Ltd.), HITALOID 7663 (trade name of Hitachi Kasei Co., Ltd.), NKOLIGO EA-6320/PGMAC, EA-6340/PGMAC (trade name of Nippon Kasei Co., Ltd.), and the like.

Examples of the aliphatic epoxy (meth) acrylate include EBECRYL 3500, EBECRYL 3608, EBECRYL 3702 (trade name of DAICEL ALLNEX Co., Ltd., the above), and Miramer PE230 (trade name of Toyo chemical Co., Ltd.).

Among the epoxy (meth) acrylate resins, bisphenol type epoxy (meth) acrylate resins such as bisphenol a type epoxy (meth) acrylate resins, bisphenol F type epoxy (meth) acrylate resins, and bisphenol E type epoxy (meth) acrylate resins, which have relatively low viscosity and excellent heat resistance, are preferable.

The viscosity of the epoxy (meth) acrylate resin at 40 ℃ is preferably in the range of 100 to 40000 mPas. The compounding ratio of the epoxy (meth) acrylate resin is preferably in the range of 5 to 50 parts by mass, more preferably 10 to 35 parts by mass, per 100 parts by mass of the curable composition of the present invention. When the amount of the epoxy (meth) acrylate resin is 5 parts by mass or more, the effect of improving the gold plating resistance can be obtained, and when the amount is 50 parts by mass or less, the compatibility is improved, and the epoxy (meth) acrylate resin is uniformly dispersed, and good coating film characteristics can be obtained. The epoxy (meth) acrylate resin may be used alone in 1 kind or in combination of 2 or more kinds.

[ (E) 2-functional (meth) acrylate Compound ]

The curable composition of the present invention may further contain (E) a 2-functional (meth) acrylate compound. (E) The 2-functional (meth) acrylate compound is preferably used as a reactive diluent because the balance between the dilution effect and the heat resistance is good. By blending (E) 2-functional (meth) acrylate compound, the viscosity of the curable composition can be reduced. Specific examples of the 2-functional (meth) acrylate compound include 1, 4-butanediol diacrylate, 1, 6-hexanediol diacrylate, 1, 9-nonanediol diacrylate, 1, 10-decanediol diacrylate and other diol diacrylates, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, neopentyl glycol diacrylate, diol diacrylates obtained by adding at least 1 of ethylene oxide and propylene oxide to neopentyl glycol, caprolactone-modified hydroxypivalic acid neopentyl glycol diacrylate and other diol diacrylates, bisphenol A EO adduct diacrylates, and mixtures thereof, Bisphenol a PO adduct diacrylate, bisphenol a diglycidyl ether acrylic adduct, tricyclodecane dimethanol diacrylate, diol diacrylate obtained by adding at least 1 of ethylene oxide and propylene oxide to tris (2-hydroxyethyl) isocyanurate bisphenol a, diacrylate having a cyclic structure such as hydrogenated dicyclopentadienyl diacrylate and cyclohexyl diacrylate, and isocyanurate diacrylate such as ethylene oxide isocyanurate-modified diacrylate.

Commercially available products include LIGHT ACRYLATE 1,6HX-A, 1,9ND-A, 3EG-A, 4EG-A (trade name of Kyoeisha chemical Co., Ltd.), HDDA, 1,9 NDA, DPGDA, TPGDA (trade name of DAICEL ALLNEX Co., Ltd.), BISCATE #195, #230D, #260, #310HP, #335HP, #700HV, #540 (trade name of Osaka organic chemical Co., Ltd.), ARNIX M-208, M-211B, M-215, M-220, M-225, M-240, and M-270 (trade name of Toyo chemical Co., Ltd.), and the like.

Among the 2-functional (meth) acrylates, diacrylates of diols having an alkylene chain are preferable from the viewpoint of viscosity and compatibility. Among them, diacrylates of diols having an alkylene chain of 4 to 12 carbon atoms are more preferable. Examples thereof include 1, 4-butanediol diacrylate, 1, 6-hexanediol diacrylate, 1, 9-nonanediol diacrylate and 1, 10-decanediol diacrylate.

The blending ratio of the (E) 2-functional (meth) acrylate compound is preferably 10 to 80 parts by mass, more preferably 30 to 60 parts by mass, per 100 parts by mass of the curable composition of the present invention. (E) When the amount of the 2-functional (meth) acrylate compound is 10 parts by mass or more, the compatibility is improved, the dispersion is uniform, and good coating film characteristics can be obtained, and when the amount is 80 parts by mass or less, the effect of improving heat resistance can be obtained. (E) The 2-functional (meth) acrylate compound may be used alone in 1 kind or in combination of 2 or more kinds.

The curable composition of the present invention may further contain (E) a reactive diluent other than the 2-functional (meth) acrylate compound. By compounding the reactive diluent, the viscosity of the curable composition can be reduced. Examples of the other reactive diluent include a photoreactive diluent and a thermoreactive diluent. Among them, a photoreactive diluent is preferable.

Examples of the photoreactive diluent include compounds having an unsaturated double bond, an oxetanyl group, and an epoxy group such as (meth) acrylates, vinyl ethers, vinyl derivatives, styrene, chloromethylstyrene, α -methylstyrene, maleic anhydride, dicyclopentadiene, N-vinylpyrrolidone, N-vinylformamide, xylylene dioxide, oxetanyl alcohol, 3-ethyl-3- (phenoxymethyl) oxetane, and resorcinol diglycidyl ether.

Among these, (meth) acrylates are preferable, and as the (meth) acrylates, those other than the (E) 2-functional (meth) acrylate compound described above, for example, monofunctional (meth) acrylate compounds, 3-functional (meth) acrylate compounds, and the like can be used.

Examples of the monofunctional (meth) acrylate compound include (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate and the like, and acryloylmorpholine. Specific examples of the 3-functional (meth) acrylate compound include 3-functional acrylates such as trimethylolpropane triacrylate, pentaerythritol triacrylate, trimethylolpropane PO-modified triacrylate, trimethylolpropane EO-modified triacrylate, and 3-functional polyester acrylate.

The blending ratio of these other reactive diluents is preferably in the range of 1 to 70 parts by mass, and more preferably in the range of 5 to 60 parts by mass, per 100 parts by mass of the curable composition of the present invention. When the amount of the other reactive diluent is 1 part by mass or more, the compatibility is improved, the dispersion is uniform, and good coating film characteristics can be obtained, and when the amount is 70 parts by mass or less, the effect of improving heat resistance can be obtained. The reactive diluent may be used alone in 1 kind or in combination of 2 or more kinds.

The amount of the monofunctional reactive diluent to be blended in the curable composition of the present invention is preferably small, and specifically, 10 parts by mass or less is preferably selected for 100 parts by mass of the curable composition of the present invention. When the amount of the monofunctional reactive diluent is small, the crosslinking density becomes high, and the properties such as welding heat resistance become more favorable.

The curable composition of the present invention may further contain a thermosetting catalyst. The thermosetting catalyst is used for further improving the thermosetting property of the thermosetting compound (C), and for example, amine compounds such as dicyandiamide and aromatic amine, imidazoles, phosphorus compounds, acid anhydrides, bicyclic amidine compounds, and the like can be used. Specifically, imidazoles such as imidazole, 1-benzyl-2-phenylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; and amine compounds such as dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, and 4-methyl-N, N-dimethylbenzylamine, and phosphorus compounds such as triphenylphosphine. More specifically, examples of the imidazole compounds include 1B2PZ, 2E4MZ, 2MZ-A, 2MZ-OK, 2PHZ and 2P4MHZ (manufactured by Kasei corporation of four countries); examples of the blocked isocyanate compound of dimethylamine include U-CAT3503N and-3502T (manufactured by SAN APRO Co., Ltd.); examples of the bicyclic amidine compound and salts thereof include DBU, DBN, U-CAT SA102, U-CAT5002 (available from SAN APRO Co., Ltd.). These can be used alone in 1, or in combination of 2 or more.

The content of the thermosetting catalyst is sufficient at a usual blending ratio, and is preferably 0.1 to 10 parts by mass, for example, with respect to 100 parts by mass of the (C) thermosetting compound.

In addition to the above components, the curable composition of the present invention may contain, as necessary: surface tension regulator, surfactant, delustering agent, polyester resin for adjusting the film properties, polyurethane resin, vinyl resin, acrylic resin, rubber resin, wax, red, blue, green, yellow, white, black and other commonly known colorants, for example, phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black and other, silicone, fluorine, polymer and other defoamers and leveling agents of at least 1 type, imidazole, thiazole, triazole, silane coupling agents and other adhesion imparting agents, and other commonly known additives.

The curable composition of the present invention having the above components is used in an inkjet printing method. From the above points, the viscosity at50 ℃ of the curable composition of the present invention is preferably 50 mPas or less, and particularly preferably 10 to 30 mPas. This makes it possible to perform smooth printing without applying unnecessary load to the ink jet printer. The viscosity of the curable composition of the present invention at room temperature is suitably 150mPa · s or less, and thus printing by an inkjet printing method is favorably performed. In the present invention, the viscosity is measured at normal temperature (25 ℃ C.) or 50 ℃ C. according to JIS K2283.

The curable composition of the present invention can be used for roll-to-roll printing of a flexible wiring board. In the above case, a resist pattern can be formed at high speed by mounting a light source for light irradiation, which will be described later, after the ink jet printer.

The light irradiation is performed by irradiation with ultraviolet rays or active energy, and ultraviolet rays are preferable. As a light source for light irradiation, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, an LED lamp having a wavelength in an ultraviolet region such as 365, 385, 395, 405nm, or the like is suitable. In addition, electron beams, α rays, β rays, γ rays, X rays, neutron beams, and the like can also be used. Further, if necessary, curing is performed by heating after light irradiation. The heating temperature is, for example, 80 to 200 ℃. By setting the heating temperature range, curing can be sufficiently performed. The heating time is, for example, 10 to 100 minutes.

A coating film obtained by printing the curable composition of the present invention by an ink jet method can be subjected to at least one of the above-described irradiation and heating, or both, to obtain a cured coating film having high hardness. The curable composition of the present invention has excellent adhesion to a substrate and can form a pattern-cured coating film having excellent properties such as solder heat resistance, gold plating resistance, pencil hardness, chemical resistance, and bendability.

The curable composition of the present invention can be suitably used as a permanent insulating film, for example, a solder resist for a printed wiring board. In addition, the printed circuit board of the present invention is characterized by the following aspects: the curable composition of the present invention is a curable composition for a substrate.

Examples

The present invention will be described in further detail below with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples.

The materials described in examples and comparative examples were mixed according to the formulation described in table 1 below, and premixed by a stirrer to prepare a curable composition. The values of the blending amounts in the tables represent parts by mass of the solid components unless otherwise specified.

[ Table 1]

Tu 1-1) UA-4200, 2-functional polyether urethane acrylate available from Ningmura chemical industries, Ltd., viscosity at 25 ℃ of 2000 mPas

1-2) DM576, manufactured by the company "DOUBLE BOND CHEMICAL", aliphatic 6-functional urethane acrylate oligomer having a viscosity at 25 ℃ of 1000-3000 mPas

1-3) DM776, aromatic 6-functional urethane acrylate oligomer, manufactured by DOUBLE BOND CHEMICAL, viscosity 4000-6000 mPas at 25 ℃

1-4) DAROCURE 1173, manufactured by BASF Japan K.K., 2-hydroxy-2-methyl-1-phenyl-propan-1-one,

onium 1-5) IRGACURE 819, manufactured by BASF Japan, bis (2,4, 6-trimethylbenzoyl) -phenylphosphine oxide (bisacylphosphine oxide series)

1-6) BI7982, product of Baxenden Chemical Co., Ltd., 3-functional blocked isocyanate

Tuo 1-7)4HBA 4-hydroxybutyl acrylate manufactured by Nippon chemical Co., Ltd

1-8) EA-1010N, bisphenol A epoxy resin (monofunctional) containing a (meth) acryloyl group, available from Nomuramura chemical industries, Ltd., having a viscosity at 40 ℃ of 10000 to 30000 mPas

1-9) A-NOD-N, 1, 9-nonanediol diacrylate (2-functional acrylate monomer), a product of New Zhongcun chemical industries, Ltd

H1-10) FASTOGEN BLUE 5380, produced by DIC corporation, phthalocyanine BLUE (pigment)

1-11) Cromophtal yellow AGR, manufactured by BASF Japan K.K., Cromophtal yellow (pigment)

The curable compositions of the examples and comparative examples were evaluated as follows. The results are shown in table 2 below.

(1) Viscosity at50 deg.C

The viscosity of the curable compositions obtained in the examples and comparative examples was measured at an ink temperature of 50 ℃ and 100rpm with a cone and plate viscometer (TVH-33H manufactured by Toyobo industries Co., Ltd.). The results were evaluated based on the following criteria.

O: more than 10 mPas and not more than 50 mPas.

And (delta): more than 50 mPas and not more than 200 mPas.

X: over 200 mPas.

(2) Adhesion test

The curable compositions obtained in examples 1-1 to 1-6 and comparative example were applied to a copper-clad laminate using a 30 μm applicator (manufactured by ERICHSEN Co., Ltd.), and the applied composition was measured at 150mJ/cm using a high pressure mercury lamp (HMW-713 manufactured by ORC Co., Ltd.)²And (6) curing. In examples 1 to 7, the curable composition was applied to a copper-clad laminate by ink-jet printing using MATERIAL PRINTER DMP to 2831 manufactured by FUJIFILM GLOBAL GRAPHIC SYSTEM, and the applied thickness was 150mJ/cm using an LED lamp (ANUJ 6164 manufactured by PANASONIC)²And (6) curing. Thereafter, the resultant was subjected to heating treatment in a hot air circulation type drying furnace at 150 ℃ for 60 minutes. The cross-cut tape peeling test was performed on the prepared sample. As a result, the number of remaining checkerboard was counted to several 100, and evaluation was performed based on the following criteria.

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

(3) Pencil hardness (surface hardness)

The cured coatings of the examples and comparative examples obtained under the substrate production conditions of (2) above were used to measure the pencil hardness in the surface in accordance with JISK 5600-5-4.

(4) Resistance to welding heat

The cured coating films of the examples and comparative examples obtained under the substrate production conditions of (2) above were coated with rosin-based flux, immersed in a solder bath at 260 ℃ for 10 seconds, and repeated 3 times, followed by a cross-cut tape peeling test. As a result, the number of remaining checkerboard was counted into several 100, and evaluation was performed based on the following criteria.

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

(5) Resistance to gold plating

The cured coatings of the examples and comparative examples obtained under the substrate production conditions of (2) above were plated under conditions of 0.5 μm nickel and 0.03 μm gold using commercially available electroless nickel plating baths and electroless gold plating baths, and a cross-cut tape peeling test was performed. As a result, the number of remaining checkerboard was counted into several 100, and evaluation was performed based on the following criteria.

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

[ Table 2]

As shown in the table, it was confirmed that the curable compositions of examples containing a urethane (meth) acrylate resin having a predetermined functional number and a photopolymerization initiator all had good adhesion to substrates in addition to solder heat resistance and gold plating resistance, had high hardness after curing, and had low viscosity suitable for inkjet printing.

It is understood that in examples 1-1 to 1-4, a curable composition having a low viscosity and a high hardness can be obtained by using a polyfunctional and low-viscosity aliphatic 6-functional urethane acrylate oligomer as the urethane (meth) acrylate resin. In addition, in examples 1-5 to 1-7 in which a polyfunctional and low-viscosity aromatic 6-functional urethane acrylate oligomer was similarly used as the urethane (meth) acrylate resin, a curable composition having a low viscosity and high hardness was also obtained.

On the other hand, comparative example 1-1, which did not contain a urethane (meth) acrylate resin, was inferior in soldering heat resistance and gold plating resistance. In addition, in comparative examples 1-2 to 1-4 containing no thermosetting compound, the solder heat resistance and the gold plating resistance were further reduced, and the adhesion was deteriorated, and in comparative examples 1-4 containing no 2-functional acrylate monomer, the viscosity was increased, and the ink jet printing was not suitable.

The materials described in examples and comparative examples were mixed according to the formulation described in table 3 below, and premixed by a stirrer to prepare a curable composition. The values of the blending amounts in the tables represent parts by mass of the solid components unless otherwise specified.

[ Table 3]

Tu 2-1) UA-4200, 2-functional polyether urethane acrylate available from Ningmura chemical industries, Ltd., viscosity at 25 ℃ of 2000 mPas

2-2) DM576, manufactured by the company "DOUBLE BOND CHEMICAL", aliphatic 6-functional urethane acrylate oligomer having a viscosity at 25 ℃ of 1000-3000 mPas

2-3) DM776, aromatic 6-functional urethane acrylate oligomer manufactured by DOUBLE BOND CHEMICAL, viscosity 4000-6000 mPa.s at 25 ℃

2-4) DAROCURE 1173, manufactured by BASF Japan K.K., 2-hydroxy-2-methyl-1-phenyl-propan-1-one,

onium 2-5) IRGACURE 819, manufactured by BASF Japan, bis (2,4, 6-trimethylbenzoyl) -phenylphosphine oxide (bisacylphosphine oxide series)

2-6) A-NOD-N, 1, 9-nonanediol diacrylate (2-functional acrylate monomer), a product of New Zhongcun chemical industries, Ltd

2-7) EA-1010N, bisphenol A type epoxy resin (monofunctional) containing (meth) acryloyl group, manufactured by Nomuramura chemical industries, Ltd., having a viscosity at 40 ℃ of 10000 to 30000 mPas

PO-modified bisphenol A type epoxy acrylate (bisphenol A PO2mol adduct, diglycidyl ether acrylic acid adduct) manufactured by KSM corporation 3002-8

Tuo 2-9)4HBA 4-hydroxybutyl acrylate manufactured by Nippon chemical Co., Ltd

2-10) BI7982, product of Baxenden, 3-functional blocked isocyanates

2-11) FASTOGEN BLUE 5380, produced by DIC corporation, phthalocyanine BLUE (pigment)

2-12) Cromophtal yellow AGR, manufactured by BASF Japan K.K., Cromophtal yellow (pigment)

The curable compositions of the examples and comparative examples were evaluated as follows. The results are shown in table 4 below.

(1) Viscosity at50 deg.C

O: more than 10 mPas and not more than 50 mPas.

And (delta): more than 50 mPas and not more than 200 mPas.

X: over 200 mPas.

(2) Adhesion test

The curable compositions obtained in examples 2-1 to 2-7 and comparative example were applied to a copper-clad laminate using a 30 μm applicator (manufactured by ERICHSEN Co., Ltd.), and the applied composition was measured at 150mJ/cm using a high-pressure mercury lamp (HMW-713 manufactured by ORC Co., Ltd.)²And (6) curing. In examples 2 to 8, the curable composition was applied to a copper-clad laminate by ink-jet printing using MATERIAL PRINTER DMP to 2831 manufactured by FUJIFILM GLOBAL GRAPHIC SYSTEM, and the applied thickness was 150mJ/cm using an LED lamp (ANUJ 6164 manufactured by PANASONIC)²And (6) curing. Thereafter, the resultant was subjected to heating treatment in a hot air circulation type drying furnace at 150 ℃ for 60 minutes. The cross-cut tape peel test was performed on the prepared samples. As a result, the number of remaining checkerboard was counted into several 100, and evaluation was performed based on the following criteria.

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

(3) Pencil hardness (surface hardness)

(4) Resistance to welding heat

The rosin flux was applied to the cured coatings of the examples and comparative examples obtained under the substrate production conditions of (2) above, immersed in a solder bath at 260 ℃ for 10 seconds, repeated 3 times, and then subjected to a cross-cut tape peeling test. As a result, the number of remaining checkerboard was counted into several 100, and evaluation was performed based on the following criteria.

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

(5) Resistance to gold plating

◎：100/100。

○：80～99/100。

△：60～79/100。

X: less than 59/100.

[ Table 4]

In examples 2-1 to 2-4, it is understood that a curable composition having a low viscosity and a high hardness can be obtained by using an aliphatic 6-functional urethane acrylate oligomer having a polyfunctional and low viscosity as the urethane (meth) acrylate resin, and that the viscosity becomes high when the amount of the urethane (meth) acrylate resin is too large as in examples 2-5. Furthermore, in examples 2-6 to 2-8 in which a polyfunctional and low-viscosity aromatic 6-functional urethane acrylate oligomer was similarly used as the urethane (meth) acrylate resin, a curable composition having a low viscosity and high hardness was also obtained.

On the other hand, comparative example 2-1 containing no urethane (meth) acrylate resin and comparative example 2-2 containing no epoxy (meth) acrylate resin were inferior in soldering heat resistance and gold plating resistance. In addition, in comparative examples 2 to 3 which did not contain the 2-functional acrylate monomer, the viscosity became high, and it became unsuitable for ink-jet printing.

Claims

1. A curable composition for inkjet, comprising:

(A) a urethane (meth) acrylate resin having 5 or more and 12 or less functions;

(B) a photopolymerization initiator;

(C) a heat-curable compound having at least 1 heat-reactive functional group, wherein the (C) heat-curable compound is other than an epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group; and the combination of (a) and (b),

(D) an epoxy (meth) acrylate resin having at least 1 (meth) acryloyl group,

the thermosetting compound (C) includes: a1 st thermosetting compound having at least 1 (meth) acryloyl group and at least 1 thermoreactive functional group; and, a2 nd thermosetting compound having at least 2 thermally reactive functional groups,

the (D) epoxy (meth) acrylate resin is a monofunctional bisphenol epoxy (meth) acrylate resin.

2. The curable composition for inkjet according to claim 1, wherein the viscosity of the urethane (meth) acrylate resin (A) at 25 ℃ is 1000 to 20000 mPas.

3. The curable composition for inkjet according to claim 1, further comprising: (E) a 2-functional (meth) acrylate compound.

4. The curable composition for inkjet according to claim 3, wherein the (E) 2-functional (meth) acrylate compound is a compound having an alkylene chain having 4 to 12 carbon atoms.

5. The curable composition for inkjet according to claim 1, wherein the viscosity at50 ℃ is 50 mPas or less.

6. A cured coating film obtained by curing the curable composition for inkjet according to claim 1.

7. A printed wiring board having the cured coating film according to claim 6 on a substrate.