TWI705113B - Curable composition for inkjet, cured coating film and printed circuit board using it - Google Patents

Abstract

The present invention provides not only the properties of solder heat resistance or gold plating resistance, but also good adhesion to the substrate, high hardness after curing, and low viscosity inkjet curability suitable for inkjet printing. The composition, the hardened coating film formed by hardening, and the printed circuit board having the hardened coating film on the substrate.

A curable composition for inkjet, which contains (A) a urethane (meth)acrylate resin having 5 functions or more and 12 functions or less, and (B) a photopolymerization initiator.

Description

Curable composition for inkjet, cured coating film and printed circuit board using it

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

In recent years, as a method of forming an etching resist, a solder resist, a symbol mark, etc. on a printed wiring board, a printing method using an inkjet method has attracted attention from the viewpoint of simplicity (Patent Document 1).

[Prior technical literature] 〔Patent Literature〕

Patent Document 1: International Publication No. 2004/099272

On the other hand, various curable compositions for printed circuit boards, such as resist inks or marking inks formed on printed circuit boards, require substrates such as conductive circuit metal conductor layers or plastic substrates. Good adhesion, high hardness after hardening, and require solder heat resistance or gold plating resistance under severe conditions.

However, it is difficult to meet the printability (coating properties) of the inkjet method for the design of the composition used in inkjet printing and it is difficult to meet all the required performances as described above.

Therefore, the purpose of the present invention is to provide a solder heat resistance or gold plating resistance and other characteristics, also has good adhesion to the substrate, has high hardness after hardening, and has a low viscosity suitable for inkjet printing Curable composition for inkjet, cured coating film and printed circuit board using it.

As a result of active research, the inventors found that a curable composition containing a urethane (meth)acrylate resin with a specific functional number and a photopolymerization initiator can solve the above-mentioned problems, thus completing the present invention .

That is, the curable composition for inkjet of the present invention is characterized by containing (A) a urethane (meth)acrylate resin having 5 functions or more and 12 functions or less, and (B) a photopolymerization initiator .

In the curable composition of the present invention, the viscosity of the aforementioned (A) urethane (meth)acrylate resin at 25°C is preferably 1,000 to 20,000 mPa. s. In addition, the curable composition of the present invention is better One step contains (C) a thermosetting compound having at least one thermoreactive functional group (excluding epoxy (meth)acrylate resin having at least one (meth)acrylic acid group), as the aforementioned (C) thermosetting The compound (except the epoxy (meth)acrylate resin having at least one (meth)acrylic acid group) preferably contains a first thermosetting having at least one (meth)acrylic acid group and at least one thermally reactive functional group And a second thermosetting compound having at least two thermoreactive functional groups. Furthermore, the curable composition of the present invention preferably further contains (D) an epoxy (meth)acrylate resin having at least one (meth)acrylic acid group, and the aforementioned (D) epoxy (meth)acrylate The resin is preferably a bisphenol type epoxy (meth)acrylate resin. Furthermore, the curable composition of the present invention preferably further contains (E) a bifunctional (meth)acrylate compound, and the (E) bifunctional (meth)acrylate compound preferably has 4 to 4 carbon atoms. Compound of 12 alkylene chain. Furthermore, the curable composition of the present invention preferably has a viscosity of 50 mPa at 50°C. s or less.

The cured coating film of the present invention is characterized by curing the curable composition for inkjet of the present invention described above.

The printed circuit board of the present invention is characterized by having the above-mentioned cured coating film of the present invention on the substrate.

According to the present invention, in addition to the characteristics of solder heat resistance or gold plating resistance, it also has good adhesion to the substrate, has high hardness after hardening, and has a low viscosity suitable for inkjet printing. Curable composition for inkjet, cured coating film and printed circuit board using it.

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

In addition, in the present invention, the term "hard composition" means a composition hardened by light, heat, or both. In addition, the so-called (meth)acrylate-based acrylate, methacrylate, and the general term of the mixture thereof are the same for other similar surfaces.

The curable composition for inkjet of the present invention is characterized by containing (A) a urethane (meth)acrylate resin having 5 or more functions and 12 or less functions, and (B) a photopolymerization initiator.

[(A) Urethane (meth)acrylate resin with more than 5 functions and less than 12 functions]

The so-called (A) urethane (meth)acrylate resin is a compound having plural urethane bonds and plural (meth)acrylic groups. Examples of the 5-functional urethane (meth)acrylate resin that can be used in the present invention are DM850 manufactured by DOUBLE BOND CHEMICAL, HITALOID 7903-1 manufactured by Hitachi Chemical Corporation, and the like. In addition, examples of 6-functional urethane (meth)acrylate resins are U-6LPA and UA-1100H manufactured by Shinnakamura Chemical Industry Co., CN975 manufactured by SATOMER, EBECRYL 220 and KRM8200AE manufactured by DAICEL ALLNEX. , EBECRYL 8254, EBECRYL 8301R, DM527, DM528 made by DOUBLE BOND CHEMICAL DM571, DM576, DM776, DM87A, DM88A, Hitachi Chemical Corporation's HITALOID 7902-1, TA24-195H, etc.

In addition, examples of 9-functional urethane (meth)acrylate resins include KRM8904 manufactured by DAICEL ALLNEX, HITALOID 7903-3 and HITALOID 7903-B manufactured by Hitachi Chemical Co., Ltd., etc. Furthermore, examples of 10-functional urethane (meth)acrylate resins include KRM8452 manufactured by DAICEL ALLNEX, DM588 manufactured by DOUBLE BOND CHEMICAL, and the like. In addition, examples of 12-functional urethane (meth)acrylate resins include DM5812 manufactured by DOUBLE BOND CHEMICAL, HITALOID 7903-4 manufactured by Hitachi Chemical Co., Ltd., and the like. These urethane (meth)acrylate resins can be used alone or as a mixture of two or more kinds.

In order to keep the viscosity of the whole composition low, the viscosity of (A) urethane (meth)acrylate resin at 25°C is preferably 1,000 to 20,000 mPa. s, particularly preferably 1,000 to 10,000 mPa. s. By using a relatively low-viscosity (A) urethane (meth)acrylate resin, the viscosity of the entire composition is suppressed to be low, and the ejectability and stability during inkjet printing can be improved. By using urethane (meth)acrylate resins with more than 5 functions, heat resistance is provided, and by using urethane (meth)acrylate resins with less than 12 functions, the formation of The coating film imparts flexibility and improves adhesion and other properties. It is more preferably 8 functions or less, and more preferably 6 functions or less.

(A) The tone of urethane (meth)acrylate resin The compounding amount is preferably 0.5 to 60 parts by mass, more preferably 1.5 to 55 parts by mass based on 100 parts by mass of the curable composition. By making the blending amount of the urethane (meth)acrylate resin 0.5 parts by mass or more, good solder heat resistance and gold plating resistance can be ensured. In addition, by making the blending amount of the urethane (meth)acrylate resin 60 parts by mass or less, the viscosity of the curable composition can be suppressed to be low, and the ejectability during inkjet printing can be well ensured . Stability.

[(B) Photopolymerization initiator]

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

Examples of photo-radical polymerization initiators include benzyl and benzyl ethers such as benzyl, benzyl methyl ether, benzyl ethyl ether, and benzyl propyl ether; 2-hydroxy-2 -Methyl-1-phenylpropane-1-one and other alkyl phenone series, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy Acetophenones such as -2-phenylacetophenone and 1,1-dichloroacetophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinepropane- 1-ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butan-1-one, N,N-dimethylamino acetophenone and other amines Acetophenones; anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone; 2,4-dimethylthioxanthone , 2,4-Diethylthioxanthone, 2-chlorothioxanthone, 2,4-Diisopropylthioxanthone and other thioxanthones; acetophenone dimethyl ketal, benzyl dimethyl ketal Ketal etc. Ketals; 2,4,5-triarylimidazole dimer; riboflavin tetrabutyrate; 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, etc. Alcohol compounds; 2,4,6-tris-s-triazine, 2,2,2-tribromoethanol, tribromomethyl phenyl sulfide and other organic halogen compounds; benzophenone, 4,4'-bis Benzophenones or xanthones such as diethylaminobenzophenone; 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethyl) Benzoyl)-phenyl phosphine oxide and other phenyl phosphine oxides.

The conventionally used photopolymerization initiators can be used alone or as a mixture of two or more, and furthermore, N,N-dimethylaminobenzoic acid ethyl ester and N,N-dimethylaminobenzoic acid isopropyl can be added. It is a photo-initiating assistant for tertiary amines such as pentyl ester, pentyl 4-dimethylaminobenzoate, triethylamine and triethanolamine.

In addition, a titanocene compound of IRGACURE 784 (manufactured by BASF Corporation, Japan), which has absorption in the visible light region, can also be added to promote the photoreaction. It is not particularly limited to this, as long as it can absorb ultraviolet light or light in the visible light region and can radically polymerize unsaturated groups such as (meth)acryloyl groups, it is not limited to photopolymerization initiators and photopolymerization initiators. The starting additives can be used alone or in combination.

Examples of commercially available vendors include IRGACURE 261, 184, 369, 651, 500, 819, 907, 784, 2959, IRGACURE 1116, 1173, IRGACURE TPO (all the above are trade names manufactured by BASF Japan), ESACURE KIP150, KIP65LT , KIP100F, KT37, KT55, KTO46, KIP75/B, ONE (brand name produced by FRETELLI LAMBERTI), etc.

(B) The mixing 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, particularly preferably 5 in 100 parts by mass of the curable composition of the present invention ~15 parts by mass range. By setting the blending ratio of the (B) photopolymerization initiator within the above range, appropriate photocuring properties can be obtained.

[(C) Thermosetting compound having at least one thermoreactive functional group (except epoxy (meth)acrylate resin having at least one (meth)acryloyl group)]

(C) The thermoreactive functional group of the thermosetting compound is selected from hydroxyl, carboxyl, isocyanate, amino, imino, epoxy, oxetanyl, mercapto, methoxymethyl, and methoxy Ethyl ethyl, ethoxy methyl, ethoxy ethyl and oxazoline group, cyclic (thio) ether group, (cyclic) carbonate group, epithio group, polyoxazoline group selection At least one of conventionally used thermosetting functional groups, preferably from hydroxyl, carboxyl, isocyanate, amino, imino, epoxy, oxetanyl, mercapto, methoxymethyl At least one functional group selected from the group consisting of methoxyethyl, ethoxymethyl, ethoxyethyl, and oxazolyl.

(C) The thermosetting compound preferably has at least one (meth)acryloyl group in addition to at least one thermoreactive functional group. Generally, compounds with monofunctional heat-reactive functional groups have low molecular weights, and have the problem of volatilization while reacting with heat during thermal curing. However, by having (meth)acrylic groups, they can be used in inkjet printing. By polymerization during temporary hardening by light, it is possible to obtain good properties that do not volatilize when hardened by heat.

In the present invention, as the (C) thermosetting compound, it is preferable to use in combination a first thermosetting compound having at least one (meth)acrylic group and at least one thermoreactive functional group and a first thermosetting compound having at least two thermosetting groups. The second thermosetting compound of the reactive functional group. As a result, the solder heat resistance can be further improved.

Among the above-mentioned heat-reactive functional groups, specific examples of hydroxyl groups are 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and pentaerythritol three. (Meth)acrylate, dipentaerythritol monohydroxypentane (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc., as commercially available products are LIGHT ESTER HO, LIGHT ESTER HOP, LIGHT ESTER HOA (above Is the trade name of Kyoeisha Chemical Co., Ltd.), etc.

Specific examples of the thermosetting compound whose thermoreactive functional group is a carboxyl group include acrylic acid, methacrylic acid, acrylic acid dimer, 2-methacryloxyethyl succinic acid, and methacryloxyethyl Hexahydrophthalic acid, monohydroxyethyl phthalate acrylate, etc., as commercially available products are LIGHT ESTER HO-MS, LIGHT ESTER HO-HH (the above are the trade names of Kyoeisha Chemical Co., Ltd.) , ARNIX M-5400 (trade name of East Asia Synthetic Chemical Co., Ltd.), etc.

Specific examples of the thermosetting compound whose thermoreactive functional group is an isocyanate group are 2-methacryloxyethyl isocyanate (for example, a trade name manufactured by Showa Denko Corporation, MOI).

Specific examples of thermosetting compounds in which the thermoreactive functional group is an amino group are acrylamide, N,N-dimethylaminoethyl acrylic acid Ester, N,N-dimethylaminoethyl methacrylate, N,N-diethylaminoethyl acrylate, N,N-diethylaminoethyl methacrylate, etc.

Specific examples of the thermosetting compound in which the thermoreactive functional group is an epoxy group are glycidyl methacrylate, alicyclic epoxy resins containing (meth)acrylic acid groups, and (meth)acrylic acid resins. Based on bisphenol A epoxy resin, etc. Examples of commercially available products of alicyclic epoxy resins containing (meth)acrylic acid groups are CYCLOMER M100, CYCLOMER A200, and CYCLOMER 2000 (the above are the trade names of DAICEL (Stock)). Examples of commercially available products of bisphenol A epoxy resin containing (meth)acrylic acid groups are NK OLIGO EA-1010N, EA-1010LC, EA-1010NT (the above are the trade names manufactured by Shinnakamura Chemical Industry Co., Ltd.), etc. .

Specific examples of the thermosetting compound whose thermoreactive functional group is oxetanyl include oxetanyl (meth)acrylate, etc., and commercially available products include OXE-10 and OXE-30 (Osaka Organic Chemical (Stock) system of commodity names) etc.

Specific examples of the thermosetting compound in which the thermally reactive functional group is a mercapto group include ethyl thioacrylate, ethyl methacrylate, biphenyl thioacrylate, biphenyl thioester methacrylate, and nitrophenyl thioacrylate. , Nitrophenyl thio methacrylate, triphenyl methyl thio acrylate, triphenyl methyl thio methacrylate, 1,2-bis[(2-mercaptoethyl)thio]-3-mercaptopropane Triacrylate, 2-(mercaptomethyl)-methyl of 2-acrylic acid, 2-[(2-mercaptoethyl)thio]ethyl of methacrylic acid, etc.

Specific examples of the thermosetting compound whose thermoreactive functional group is methoxymethyl include methoxymethyl acrylate and methacrylic acid. Methoxyethyl, dimethoxymethyl acrylate, dimethoxymethyl methacrylate, etc., as commercially available products include NIKALAC MX-302 (acrylic modified alkylated melamine, manufactured by Sanwa Chemical Co., Ltd.) The product name) and so on.

Specific examples of the thermosetting compound in which the thermoreactive functional group is methoxyethyl are 1-methoxyethyl acrylate, 1-methoxyethyl methacrylate, and 2-methoxyethyl acrylate , 2-Methoxyethyl methacrylate, 1,1-methoxyethyl acrylate, 1,1-methoxyethyl methacrylate, etc.

Specific examples of the thermosetting compound whose thermoreactive functional group is ethoxyethyl are 1-ethoxyethyl acrylate, 1-ethoxyethyl methacrylate, and 2-ethoxyethyl acrylate. , 2-ethoxyethyl methacrylate, etc.

Specific examples of the thermosetting compound whose thermoreactive functional group is ethoxymethyl are N-ethoxymethacrylamide, N-ethoxymethacrylamide, and acrylic ethoxy Methyl ester, ethoxy methyl methacrylate, etc.

A specific example of a thermosetting compound in which the thermoreactive functional group is an oxazoline group is 2-methyl-2-{[3-(4,5-dihydro-2-oxazolyl) of 2-acrylic acid Benzyl)amino) ethyl ester, 2-methyl-2-(4,5-dihydro-2-oxazolyl) ethyl ester of 2-acrylic acid, 3-(4,5-acrylic acid) Dihydro-4,4-dimethyl-2-oxazolyl)propyl ester and the like.

In addition, as a thermosetting compound having two or more thermoreactive functional groups, amino resins such as melamine resin, benzoguanidine resin, melamine derivatives, benzoguanidine derivatives, and blocked isocyanate compounds can be used. Conventional thermosetting resins such as cyclic carbonate compounds, thermosetting components with cyclic (thio) ether groups, bismaleimide, carbodiimide resin, etc. From the viewpoint of excellent storage stability, a blocked isocyanate compound is particularly preferred.

The above-mentioned thermosetting compound having a plurality of cyclic (thio) ether groups in the molecule is any one or two groups of cyclic (thio) ether groups with a plurality of 3, 4 or 5-membered rings in the molecule Compounds such as compounds with multiple epoxy groups in the molecule, that is, polyfunctional epoxy compounds, compounds with multiple oxetanyl groups in the molecule, that is, polyfunctional oxetane compounds, and multiple sulfur in the molecule Ether-based compounds are episulfide resins and the like.

Examples of the above-mentioned polyfunctional epoxy compounds are epoxidized vegetable oils such as ADEKACIZER O-130P, ADEKACIZER O-180A, ADEKACIZER D-32, ADEKACIZER D-55 manufactured by ADEKA; jER828, jER834, jER1001, jER1004 manufactured by Mitsubishi Chemical , EPICLON 840, EPICLON 850, EPICLON 1050, EPICLON 2055, EPITOT YD-011, YD-013, YD-127, YD-128, DER317, DER331, and DOW CHEMICAL manufactured by DIC DER661, DER664, SUMI EPOXY ESA-011, ESA-014, ELA-115, ELA-128 manufactured by Sumitomo Chemical Industries, AER330, AER331, AER661, AER664 manufactured by Asahi Kasei Industries, etc. (all (Trade name) Bisphenol A epoxy resin; Hydroquinone epoxy resin such as YDC-1312, Bisphenol epoxy resin such as YSLV-80XY, Sulfide type epoxy resins such as YSLV-120TE (all manufactured by Toto Kasei); jERYL903 manufactured by Mitsubishi Chemical Corporation, EPICLON 152 and EPICLON165 manufactured by DIC, EPITOT YDB-400, YDB-500, manufactured by Toto Chemicals Brominated epoxy resins such as DER542 made by DOW CHEMICAL, SUMI EPOXY ESB-400, ESB-700 made by Sumitomo Chemical Industries, AER711, AER714 made by Asahi Kasei Kogyo Co., Ltd. (all trade names); Mitsubishi Chemical JER152, jER 154 manufactured by the company, DEN431, DEN438 manufactured by DOW CHEMICAL, EPICLON N-730, EPICLON N-770, EPICLON N-865 manufactured by DIC, EPITOT YDCN-701, YDCN- manufactured by Dongdu Chemical Co., Ltd. 704. EPPN-201, EOCN-1025, EOCN-1020, EOCN-104S, RE-306 manufactured by Nippon Kayaku Co., Ltd., SUMI EPOXY ESCN-195X, ESCN-220 manufactured by Sumitomo Chemical Industry Co., Ltd., AER manufactured by Asahi Kasei Industrial Co., Ltd. Novolac epoxy resins such as ECN-235, ECN-299 (all trade names); NC-3000, NC-3100, etc. bisphenol novolac epoxy resins manufactured by Nippon Kayaku Corporation; manufactured by DIC EPICLON 830, jER807 manufactured by Mitsubishi Chemical Corporation, EPOTOT YDF-170, YDF-175, YDF-2004, etc. (all trade names) manufactured by Toto Chemical Co., Ltd. Bisphenol F epoxy resin; EPOTOT ST manufactured by Toto Chemical Co., Ltd. -2004, ST-2007, ST-3000 (trade name), etc. hydrogenated bisphenol A epoxy resin; jER604 manufactured by Mitsubishi Chemical Corporation, EPOTOT YH-434 manufactured by Toto Kasei Co., Ltd., and SUMI EPOXY manufactured by Sumitomo Chemical Industries, Ltd. Glycidylamine type epoxy resin such as ELM-120 (all trade names); hydantoin type epoxy resin; grease Cyclic epoxy resin; YL-933 manufactured by Mitsubishi Chemical Corporation, TEN, EPPN-501, EPPN-502 manufactured by DOW CHEMICAL, etc. (all trade names) trihydroxyphenylmethane type epoxy resin; Mitsubishi Chemical Corporation Bixylenol type or biphenol type epoxy resins made by YL-6056, YX-4000, YL-6121 (all trade names), etc. or their mixture; EBPS-200, ADEKA made by Nippon Kayaku Co., Ltd. Bisphenol S type epoxy resin such as EPX-30, EXA-1514 (trade name) produced by DIC Corporation; Bisphenol A novolac type epoxy resin such as jER157S (trade name) produced by Mitsubishi Chemical Corporation; Mitsubishi Tetrahydroxyphenylethane type epoxy resin such as jERYL-931 (all trade names) manufactured by Chemical Company; Heterocyclic epoxy resin such as TEPIC (all trade names) manufactured by Nissan Chemical Industry Co., Ltd.; Nippon Oil & Fats Diglycidyl phthalate resin such as BRENMER DGT manufactured by the company; Tetraglycidyl xylenol ethane resin such as ZX-1063 manufactured by Toto Kasei; ESN-190, ESN manufactured by Nippon Steel Chemical Company -360, HP-4032, EXA-4750, EXA-4700 manufactured by DIC Company containing naphthyl group-containing epoxy resin; DIC Company manufactured HP-7200, HP-7200H and other epoxy resins with dicyclopentadienyl structure Resin; glycidyl methacrylate copolymerized epoxy resin of CP-50S, CP-50M manufactured by Nippon Oil & Fat Co., Ltd.; and a copolymerized epoxy resin of cyclohexyl maleimide and glycidyl methacrylate; Epoxy-modified polybutadiene rubber derivatives, CTBN-modified epoxy resins (such as YR-102, YR-450 manufactured by Toto Kasei Co., Ltd.), etc., but not limited to these. These epoxy resins can be used individually or in combination of 2 or more types. Among them, novolak type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin, and biphenol phenol resin are particularly preferred. Varnish type epoxy resin, naphthalene type epoxy resin or a mixture of these.

Examples of polyfunctional oxetane compounds 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-oxetanylmethyl Oxy)methyl)benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) methyl acrylate, (3- Multifunctional oxygen heterocycles such as methyl-3-oxetanyl) methyl ester, (3-ethyl-3-oxetanyl) methyl methacrylate or the oligomers or copolymers thereof Butanes, in addition to exemplified are oxetane and novolac resins, poly(p-hydroxystyrene), cardo type bisphenols, calixarenes, resorcinarenes (calix resorcinarenes) Etherate of resins with hydroxyl groups such as silsesquioxane, etc. In addition, examples include copolymers of unsaturated monomers having oxetane rings and alkyl (meth)acrylates.

Examples of compounds having plural cyclic thioether groups in the molecule include bisphenol A type episulfide resin YL7000 manufactured by Mitsubishi Chemical Corporation. Furthermore, an episulfide resin in which the oxygen atom of the epoxy group of the novolak type epoxy resin is substituted with a sulfur atom by the same synthesis method can also be used.

Examples of amine-based resins such as melamine derivatives and benzoguanidine derivatives include methylol melamine compounds, methylol benzoguanidine compounds, methylol glycol urea compounds and methylol urea compounds. Furthermore, alkoxymethylated melamine compounds, alkoxymethylated benzoguanidine compounds, alkoxymethylated glycol urea compounds, and alkylmethylated urea compounds can be The methylol groups of methylol melamine compounds, methylol benzoguanidine compounds, methylol glycol urea compounds and methylol urea compounds are converted into alkoxymethyl groups. The type of these alkoxymethyl groups is not particularly limited, and may be, for example, methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl, and the like. Particularly preferred is a melamine derivative having a formaldehyde concentration of 0.2% by mass or less which is excellent for the human body or environment.

As such commercially available products, for example, CYMEL 300, CYMEL 301, CYMEL 303, CYMEL 370, CYMEL 325, CYMEL 327, CYMEL 701, CYMEL 266, CYMEL 267, CYMEL 238, CYMEL 1141, CYMEL 272, CYMEL 202, CYMEL 1156, CYMEL 1158, CYMEL 1123, CYMEL 1170, CYMEL 1174, CYMEL UFR65, CYMEL 300 (all manufactured by Mitsui CYANAMIDE), NIKALAC Mx-750, NIKALAC Mx-032, NIKALAC Mx-270, NIKALAC Mx-280, NIKALAC Mx -290, NIKALAC Mx-706, NIKALAC Mx-708, NIKALAC Mx-40, NIKALAC Mx-31, NIKALAC Ms-11, NIKALAC Mw-30, NIKALAC Mw-30HM, NIKALAC Mw-390, NIKALAC Mw-100LM, NIKALAC Mw -750LM (all manufactured by Sanwa Chemical Co.), etc.

The isocyanate compound and the blocked isocyanate compound are compounds having a plurality of isocyanate groups or blocked isocyanate groups in one molecule. Examples of such compounds having a plurality of isocyanate groups or blocked isocyanate groups in one molecule are polyisocyanate compounds or blocked isocyanate compounds. In addition, the blocked isocyanate group isocyanate group is combined with The blocking agent reacts to protect and temporarily inactivate the group, and the blocking group dissociates when heated to a specific temperature to form an isocyanate group. By adding the above-mentioned isocyanate compound or blocked isocyanate compound, it was confirmed that the curability and the toughness of the obtained cured product can be improved.

As these polyisocyanate compounds, for example, aromatic polyisocyanates, aliphatic polyisocyanates, or alicyclic polyisocyanates are used.

Specific examples of aromatic polyisocyanates include, for example, 4,4'-diphenylmethane diisocyanate, 2,4-xylyl diisocyanate, 2,6-toluene diisocyanate, naphthalene-1,5-diisocyanate, O-xylene diisocyanate, m-xylene diisocyanate, 2,4-toluene dimer, etc.

Specific examples of aliphatic polyisocyanates include tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylene bis(cyclo Hexyl isocyanate) and isophorone diisocyanate.

As a specific example of the alicyclic polyisocyanate, bicycloheptane triisocyanate is exemplified. In addition, examples are the adduct, uret, and isocyanurate of the isocyanate compound exemplified previously.

As the blocked isocyanate compound, an addition reaction product of an isocyanate compound and an isocyanate blocking agent is used. Examples of isocyanate compounds that can react with the blocking agent include the above-mentioned polyisocyanate compounds and the like.

Examples of isocyanate blocking agents include phenolic blocking agents such as phenol, cresol, xylenol, chlorophenol, and ethylphenol; ε-caprolactone, δ-valerolactam, γ-butyrolactone Amine and β-propiolactam Ending agent; active methylene-based end-capping agent such as ethyl acetate and acetone; 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, ethyl lactate, etc. Ending agents; oxime-based end-capping agents such as formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diethyl ketone oxime, cyclohexanone oxime, etc.; butyl mercaptan, hexyl mercaptan, third Thiol-based blocking agents such as butyl mercaptan, thiophenol, methyl thiophenol, and ethyl thiophenol; amide-based blocking agents such as amide acetate and benzamide; succinimide and horse Imidazole-based blocking agents such as Leximine; Amine-based blocking agents such as xylene amine, benzylamine, butylamine, and dibutylamine; Imidazole-based blocking agents such as imidazole and 2-ethylimidazole Ending agents; imine-based end-capping agents such as methylene imine and propylene imine.

The blocked isocyanate compound can also be commercially available, such as SUMIDUR BL-3175, BL-4165, BL-1100, BL-1265, DESMODUR TPLS-2957, TPLS-2062, TPLS-2078, TPLS-2117, DESMOTHERM 2170, DESMOTHERM 2265 (all manufactured by Sumitomo Bayer Carbamate), CORONATE 2512, CORONATE 2513, CORONATE 2520 (all manufactured by Japan Polyurethane Industry Co.), B-830, B-815, B-846, B-870, B-874, B-882 (all manufactured by Mitsui Takeda Chemical Co., Ltd.), TPA-B80E, 17B-60PX, E402-B80T (all manufactured by Asahi Kasei Chemical Co., Ltd.), etc. In addition, SUMIDUR BL-3175 and BL-4265 can also be obtained by using methyl ethyl oxime as a blocking agent. The compound having multiple isocyanate groups or blocked isocyanate groups in one molecule can be used alone or in combination Use more than 2 kinds.

(C) The blending ratio of the thermosetting compound is preferably in the range of 10 to 70 parts by mass, more preferably in the range of 20 to 60 parts by mass in 100 parts by mass of the curable composition of the present invention. If the blending amount is 10 parts by mass or more, sufficient coating film strength and heat resistance will be obtained. On the other hand, if it is 70 parts by weight or less, the decrease in storage stability can be suppressed. (C) A thermosetting compound may be used individually by 1 type, and may combine 2 or more types.

[(D) Epoxy (meth)acrylate resin with at least one (meth)acrylic group]

Examples of epoxy (meth)acrylate resins having at least one (meth)acrylic acid group include bisphenol A type epoxy (meth)acrylate resin and bisphenol F type epoxy (meth)acrylate resin , Bisphenol E epoxy (meth)acrylate resin, cresol novolac epoxy (meth)acrylate resin, phenol novolak epoxy (meth)acrylate resin, aliphatic epoxy (meth)acrylate resin Base) acrylate and the like.

Examples of bisphenol A epoxy (meth)acrylate resins are EBECRYL 600, EBECRYL 605, EBECRYL 648, EBECRYL 3700, EBECRYL 3703 (the above are trade names manufactured by DAICEL ALLNEX), EPOXY ESTER EX-0205, EPOXY ESTER 3000A, EPOXY ESTER 3002A(N) (the above are the trade names of Kyoei Chemical Co., Ltd.), 8026, 8101, 8125, 8197, 8250 LMH, 8260, 8355, 8360BR, 8327, 8351 (the above are made by U-PICA Japan Product name), HITAROID 7851 (The product name manufactured by Hitachi Chemical Co., Ltd. above), BISCOTE #540 (the product name manufactured by Osaka Organic Chemical Industry Co., Ltd. above), CN104, CN104A80, CN104B80, CN120, CN120A60, CN120A75, CN120B60, CN120B80, CN120C60, CN120C80, CN120D80, CN120E50 , CN120M50, CN151 (trade name made by SATOMER above), Miramer PE210 (trade name made by Toyo Chemical Company above), NK OLIGO EA-1010N, EA-1010LC, EA-1010NT, EA-1020, EA-1020LC3, EMA -1020 (the product name produced by Shin Nakamura Chemical Industry Co., Ltd. above), etc.

Examples of bisphenol F epoxy (meth)acrylate resins are 8475, 8476 (trade names manufactured by U-PICA Japan) and the like.

Examples of the cresol novolak type epoxy (meth)acrylate resin include NK OLIGO EA-7120/PGMAC, EA-7140/PGMAC, EA-7420/PGMAC (a trade name manufactured by Shin Nakamura Chemical Co., Ltd. above).

Examples of phenol novolac type epoxy (meth)acrylate resins are 8400, 8411 LH (the product name of U-PICA, Japan), HITAROID 7663 (the product name of Hitachi Chemical), and NK OLIGO EA-6320 /PGMAC, EA-6340/PGMAC (trade name made by Shinnakamura Chemical Industry Co., Ltd. above), etc.

Examples of aliphatic epoxy (meth)acrylates are EBECRYL 3500, EBECRYL 3608, EBECRYL 3702 (above Trade name made by DAICEL ALLNEX), Miramer PE230 (trade name made by Toyo Chemical Co.), etc.

Among the above epoxy (meth)acrylate resins, bisphenol A epoxy (meth)acrylate resins and bisphenol F epoxy (meth)acrylate resins having relatively low viscosity and excellent heat resistance are preferred , Bisphenol-type epoxy (meth)acrylate resin such as bisphenol-E epoxy (meth)acrylate resin.

Furthermore, the viscosity of the epoxy (meth)acrylate resin at 40°C is preferably 100 to 40,000 mPa. The range of s. The blending ratio of the epoxy (meth)acrylate resin is preferably in the range of 5-50 parts by mass, more preferably in the range of 10-35 parts by mass in 100 parts by mass of the rigid composition of the present invention. When the blending amount of the epoxy (meth)acrylate resin is 5 parts by mass or more, the effect of improving the resistance to gold plating is obtained, and when the amount is less than 50 parts by mass, good coating characteristics with improved compatibility and uniform dispersion are obtained. Epoxy (meth)acrylate resin may be used individually by 1 type, and may be used in combination of 2 or more types.

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

The curable composition of the present invention may further contain (E) a bifunctional (meth)acrylate compound. (E) The bifunctional (meth)acrylate compound is used as a reactive diluent, and it is preferable because the dilution effect and heat resistance are well balanced. By blending (E) a bifunctional (meth)acrylate compound, the viscosity of the curable composition can be reduced. As a specific example of the bifunctional (meth)acrylate compound, 1,4-butanediol dipropylene Diacrylate, ethylene glycol diacrylate such as acrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, etc. Ester, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate Ester, neopentyl glycol diacrylate, diacrylate of diol obtained by adding at least one of ethylene oxide and propylene oxide to neopentyl glycol, caprolactone modified hydroxypivalate neopentyl glycol Diacrylate and other glycol diacrylates, bisphenol A EO adduct diacrylate, bisphenol A PO adduct diacrylate, bisphenol A diglycidyl ether acrylic acid adduct, tricyclodecane Dimethanol diacrylate, diol diacrylate obtained by adding at least one of ethylene oxide and propylene oxide to tris(2-hydroxyethyl) isocyanurate bisphenol A, hydrogenated dicyclopentane Diene diacrylate, cyclohexyl diacrylate and other diacrylates with cyclic structure, isocyanuric acid ethylene oxide modified diacrylate and other isocyanuric diacrylates.

Examples of commercially available products include tetraacrylate 1,6HX-A, 1,9ND-A, 3EG-A, 4EG-A (trade names manufactured by Kyoei Chemical Co., Ltd.), HDDA, 1,9-NDA, DPGDA , TPGDA (trade name manufactured by DAICEL ALLNEX), BISCOTE #195, #230, #230D, #260, #310HP, #335HP, #700HV, #540 (trade name manufactured by Osaka Organic Chemical Industry Co., Ltd.), ARONIX M -208, M-211B, M-215, M-220, M-225, M-240, M-270 (trade name manufactured by Toagosei Corporation), etc.

Among bifunctional (meth)acrylates, based on viscosity and phase From the viewpoint of solubility, diacrylate of a glycol having an alkylene chain is preferred. Among them, the diacrylate of a diol having an alkylene chain having 4 to 12 carbon atoms is more preferable. As examples, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, and the like are exemplified.

Furthermore, the blending ratio of (E) the bifunctional (meth)acrylate compound is preferably in the range of 10 to 80 parts by mass, more preferably 30 to 60 parts by mass in 100 parts by mass of the curable composition of the present invention The scope. (E) When the blending amount of the bifunctional (meth)acrylate compound is 10 parts by mass or more, good coating film characteristics with improved compatibility and uniform dispersion are obtained, and when it is 80 parts by mass or less, the effect of improving heat resistance is obtained. (E) A bifunctional (meth)acrylate compound may be used individually by 1 type, and may be used in combination of 2 or more types.

In the curable composition of the present invention, (E) a reactive diluent other than the bifunctional (meth)acrylate compound can be further formulated. By mixing reactive diluents, the viscosity of the curable composition can be reduced. Examples of other reactive diluents include photoreactive diluents, heat reactive diluents, and the like. Among these, a photoreactive diluent is preferred.

Examples of photoreactive diluents include (meth)acrylates, vinyl ethers, vinyl derivatives, styrene, chloromethylstyrene, α-methylstyrene, maleic anhydride, and dicyclopentadiene , N-vinylpyrrolidone, N-vinylformamide, xylene dioxetane, oxetane alcohol, 3-ethyl-3-(phenoxymethyl)oxetane Butane, cresol diglycidyl ether, etc. have unsaturated double bonds or oxetanyl groups, epoxy groups Compound.

Among these, (meth)acrylates are preferred. As the (meth)acrylates, those other than the above-mentioned (E) difunctional (meth)acrylate compounds can be used, such as monofunctional (meth)acrylates. Compounds, trifunctional (meth)acrylate compounds, etc.

Examples of monofunctional (meth)acrylate compounds include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, (meth) Lauryl acrylate, stearyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate and other (meth)acrylates , Or acryloyl morpholine and so on. Specific examples of trifunctional (meth)acrylate compounds are trimethylolpropane triacrylate, pentaerythritol triacrylate, trimethylolpropane PO modified triacrylate, trimethylolpropane EO modified triacrylate Trifunctional acrylates such as acrylates and trifunctional polyester acrylates.

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

In addition, in the curable composition of the present invention, the less the amount of the monofunctional reactive diluent is blended, the better. Specifically, the hardening composition of the present invention In 100 parts by mass of the sexual composition, 10 parts by mass or less is preferred. When the blending amount of monofunctional reactive diluent is small, the cross-linking density can be increased, so that the solder heat resistance and other properties are better.

In the curable composition of the present invention, a thermosetting catalyst can be further formulated. The thermosetting catalyst is used to further improve the thermosetting properties of (C) thermosetting compounds. For example, amine compounds such as dicyandiamide and aromatic amines, imidazoles, phosphorus compounds, acid anhydrides, and bicyclic amidines can be used. Compound etc. Specifically, imidazole, 1-benzyl-2-phenylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4- Imidazoles such as phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyanodiamide, Benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N, Amine compounds such as N-dimethylbenzylamine, phosphorus compounds such as triphenylphosphine, etc. More specifically, examples of imidazole compounds include 1B2PZ, 2E4MZ, 2MZ-A, 2MZ-OK, 2PHZ, 2P4MHZ (manufactured by Shikoku Chemical Co., Ltd.); examples of blocked isocyanate compounds of dimethylamine are U -CAT3503N, -3502T (manufactured by SAN APRO); examples of bicyclic amidine compounds and their salts include DBU, DBN, U-CAT SA102, and U-CAT5002 (manufactured by SAN APRO). These can be used individually by 1 type or in combination of 2 or more types.

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

In the curable composition of the present invention, in addition to the above-mentioned components, surface tension modifiers, surfactants, matting agents, polyester resins and polyurethane resins for adjusting the physical properties of the film can also be formulated as required. , Vinyl resins, acrylic resins, rubber resins, waxes, red, blue, green, yellow, white, black and other commonly used coloring agents, such as phthalocyanine blue, phthalocyanine green, iodine green, bisazo Yellow, crystal violet, titanium oxide, carbon black, naphthalene black, etc., at least one type of defoaming agent and leveling agent of silicone, fluorine, polymer, etc., such as imidazole, thiazole, triazole , Silane coupling agent and other conventional additives for adhesion imparting agents.

The curable composition of the present invention having the above-mentioned components is used in an inkjet printing method. Based on this aspect, the curable composition of the present invention has a viscosity of 50 mPa at 50°C. Below s, 10~30mPa is particularly preferred. s. This prevents unnecessary load on the inkjet printer and enables smooth printing. Moreover, the viscosity of the curable composition of the present invention at room temperature is preferably 150 mPa. s or less, so that the inkjet printing method can be printed well. Here, in the present invention, viscosity means the viscosity measured at room temperature (25°C) or 50°C in accordance with JIS K2283.

Furthermore, the curable composition of the present invention can be used for printing on flexible circuit boards by a roll-to-roll method. In this case, the resist pattern can be formed at a high speed by installing the light source for light irradiation described later through the inkjet printer.

Light irradiation is performed by irradiation of ultraviolet rays or active energy rays, but ultraviolet rays are preferred. As the light source for light irradiation, suitable low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, metal halide lamps, LED lamps with wavelengths in the ultraviolet range of 365, 385, 395, 405nm, etc. In addition, electron beams, α rays, β rays, γ rays, X rays, neutral beams, etc. may also be used. Furthermore, if necessary, it is cured by heating after light irradiation. Here, the heating temperature is, for example, 80 to 200°C. By setting it in this heating temperature range, it can be fully cured. The heating time is, for example, 10 to 100 minutes.

The curable composition of the present invention can be obtained by applying at least one or both of the above-mentioned light irradiation and heating to the coating film obtained by inkjet printing to obtain a hardened coating film with high hardness. The curable composition of the present invention can form a patterned hardened coating film having excellent adhesion to a substrate and excellent properties such as solder heat resistance, gold plating resistance, pencil hardness, chemical resistance, and flexibility.

The curable composition of the present invention can be preferably used as a permanent insulating film, such as a solder resist for printed circuit boards. In addition, the printed circuit board of the present invention has the characteristic of having a cured coating film formed using the curable composition of the present invention on the substrate.

[Example]

The following examples and comparative examples further illustrate the present invention in detail, but the present invention is not limited by these examples and comparative examples.

According to the formulations described in Table 1 below, the materials described in the Examples and Comparative Examples were respectively blended and pre-mixed with a mixer to prepare a curable composition. In addition, the value of the blending amount in the table indicates the mass part of the solid content, unless it is particularly limited.

*1-5) IRGACURE 819, manufactured by BASF, Japan, bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (bis(bis)phosphine oxide series)

*1-6) BI7982, manufactured by Baxenden Chemical, trifunctional blocked isocyanate

*1-7) 4HBA, manufactured by Nippon Kasei Corporation, 4-hydroxybutyl acrylate

*1-8) EA-1010N, manufactured by Shinnakamura Chemical Industry Co., Ltd., containing (meth)acrylic bisphenol A epoxy resin (monofunctional), viscosity at 40°C is 10,000~30,000mPa. s

*1-9) A-NOD-N, manufactured by Shinnakamura Chemical Industry Co., 1,9-nonanediol diacrylate (a bifunctional acrylate monomer)

*1-10) FASTOGEN BLUE 5380, manufactured by DIC, Phthalocyanine blue (pigment)

*1-11) Cromophtal yellow AGR, made by BASF Japan, cromophtal yellow (pigment)

The obtained curable composition of each Example and Comparative Example was evaluated according to the following. The results are shown in Table 2 below.

(1) Viscosity at 50℃

The viscosity of the curable composition obtained in each of the Examples and Comparative Examples was measured at an ink temperature of 50°C and 100 rpm using a laminar viscometer (TVH-33H manufactured by Toki Sangyo Co., Ltd.). The results were evaluated based on the following criteria.

○: More than 10mPa. s and 50mPa. s or less.

△: More than 50mPa. s and 200mPa. s or less.

×: More than 200mPa. s.

(2) Adhesion test

The curable compositions obtained in Examples 1-1 to 1-6 and Comparative Examples were coated on a copper-clad laminate using a 30μm applicator (manufactured by ERICHSEN), and a high-pressure mercury lamp (HMW-713 manufactured by ORC) Harden at 150mJ/cm ² . Regarding Examples 1-7, the curable composition used MATERIAL PRINTER DMP-2831 manufactured by FUJIFILM GLOBAL GRAPHIC SYSTEM, and was ink-jet coated on a copper-clad laminate, and used an LED lamp (ANUJ6164 manufactured by PANASONIC) at 150 mJ/cm ² Carry out hardening. Subsequently, heat treatment was performed for 60 minutes in a hot air circulating drying furnace at 150°C. A cross-cut tape peel test was performed on the produced samples. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

(3) Pencil hardness (surface hardness)

Using the hardened coating films of the respective Examples and Comparative Examples obtained under the substrate production conditions of (2) above, the pencil hardness of the surface was measured in accordance with JIS K 5600-5-4.

(4) Solder heat resistance

Apply rosin-based flux to the hardened coating films of each of the examples and comparative examples obtained under the substrate production conditions of (2) above, immerse in a solder tank at 260°C for 10 seconds, repeat 3 times, and peel off the cross dicing tape test. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

(5) Gold plating resistance

For the hardened coating films of each of the examples and comparative examples obtained under the substrate production conditions of (2) above, the commercially available electroless nickel plating bath and electroless gold plating bath were used for plating under the conditions of 0.5μm nickel and 0.03μm gold. Apply the cross cut tape peel test. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

As shown in the above table, the curable composition of each example containing a specific functional number of urethane (meth)acrylate resin and photopolymerization initiator is confirmed to have solder heat resistance and gold plating resistance In addition, it also has good adhesion on the substrate, high hardness after curing, and low viscosity suitable for inkjet printing.

Examples 1-1 to 1-4 use multifunctional and low-viscosity aliphatic 6-functional urethane acrylate oligomer as the urethane (meth)acrylate resin. It can be seen that low viscosity and low viscosity Hardenable composition with high hardness. In addition, regarding the examples 1-5 to 1-7 that also used the multifunctional and low-viscosity aromatic 6-functional urethane acrylate oligomer as the urethane (meth)acrylate resin, it is also A curable composition with low viscosity and high hardness is obtained.

On the other hand, in Comparative Example 1-1 which does not contain a urethane (meth)acrylate resin, the solder heat resistance and the gold plating resistance are inferior. In addition, in Comparative Examples 1-2 to 1-4 that do not contain a thermosetting compound, the solder heat resistance and gold plating resistance are further reduced, and the adhesion is deteriorated, and the Comparative Example 1-4 also contains no bifunctional acrylate monomer. , Become high viscosity and not suitable for spraying Ink printers.

According to the formulation described in the following Table 3, the materials described in the Examples and Comparative Examples were respectively formulated, and mixed in advance with a mixer to prepare a curable composition. In addition, the value of the blending amount in the table indicates the mass part of the solid content, unless it is particularly limited.

黏度1,000~3,000mPa．s

The viscosity is 1,000~3,000mPa. s

*2-3) DM776, manufactured by DOUBLE BOND CHEMICAL, aromatic 6-functional urethane acrylate oligomer, viscosity at 25℃ is 4,000~6,000mPa. s

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

*2-5) IRGACURE 819, manufactured by BASF, Japan, bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide (bis(bis)phosphine oxide series)

*2-6) A-NOD-N, manufactured by Shinnakamura Chemical Industry Co., 1,9-nonanediol diacrylate (two-functional acrylate monomer)

*2-7) EA-1010N, manufactured by Shinnakamura Chemical Industry Co., Ltd., containing (meth)acrylic bisphenol A type epoxy resin (monofunctional), viscosity at 40°C is 10,000~30,000mPa. S

*2-8) 3002A(N), manufactured by KSM, PO modified bisphenol A epoxy acrylate (bisphenol A PO2mol adduct, diglycidyl ether acrylic adduct)

*2-9) 4HBA, manufactured by Nippon Kasei Corporation, 4-hydroxybutyl acrylate

*2-10) BI7982, manufactured by Baxenden, trifunctional blocked isocyanate

*2-11) FASTOGEN BLUE 5380, manufactured by DIC, Phthalocyanine Blue (pigment)

*2-12) Cromophtal yellow AGR, made by BASF Japan, cromophtal yellow (pigment)

The obtained curable composition of each Example and Comparative Example was evaluated according to the following. The results are shown in Table 4 below.

(1) Viscosity at 50℃

The viscosity of the curable composition obtained in each of the Examples and Comparative Examples was measured at an ink temperature of 50°C and 100 rpm using a laminar viscometer (TVH-33H manufactured by Toki Sangyo Co., Ltd.). The results were evaluated based on the following criteria.

○: More than 10mPa. s and 50mPa. s or less.

△: More than 50mPa. s and 200mPa. s or less.

×: More than 200mPa. s.

(2) Adhesion test

The curable compositions obtained in Examples 2-1 to 2-7 and Comparative Examples were coated on a copper-clad laminate using a 30 μm applicator (manufactured by ERICHSEN), and a high-pressure mercury lamp (HMW-713 manufactured by ORC) Harden at 150mJ/cm ² . Regarding Examples 2-8, the curable composition used MATERIAL PRINTER DMP-2831 manufactured by FUJIFILM GLOBAL GRAPHIC SYSTEM, and was ink-jet coated on a copper-clad laminate, using LED lights (ANUJ6164 manufactured by PANASONIC) at 150mJ/cm ² Carry out hardening. Subsequently, heat treatment was performed for 60 minutes in a hot air circulating drying furnace at 150°C. A cross-cut tape peel test was performed on the produced samples. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

(3) Pencil hardness (surface hardness)

Using the hardened coating films of the respective Examples and Comparative Examples obtained under the substrate production conditions of (2) above, the pencil hardness of the surface was measured in accordance with JIS K 5600-5-4.

(4) Solder heat resistance

Apply rosin-based flux to the hardened coating films of each of the examples and comparative examples obtained under the substrate production conditions of (2) above, immerse in a solder tank at 260°C for 10 seconds, repeat 3 times, and peel off the cross dicing tape test. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

(5) Gold plating resistance

For the hardened coating films of each of the examples and comparative examples obtained under the substrate production conditions of (2) above, the commercially available electroless nickel plating bath and electroless gold plating bath were used for plating under the conditions of 0.5μm nickel and 0.03μm gold. Apply cross Cutting tape peel test. The result is to calculate how many of the remaining number of checkerboards remain in 100, and evaluate it based on the following criteria.

◎: 100/100.

○: 80~99/100

△: 60~79/100.

×: 59 or less/100.

As shown in the above table, the curable composition of each example containing a specific functional number of urethane (meth)acrylate resin and photopolymerization initiator is confirmed to have solder heat resistance and gold plating resistance In addition, it also has good adhesion on the substrate, high hardness after curing, and low viscosity suitable for inkjet printing.

Examples 2-1~2-4 use multifunctional and low-viscosity aliphatic 6-functional urethane acrylate oligomer as the urethane (meth)acrylate resin to obtain low viscosity and high A hardenable composition, but when the blending amount of the urethane (meth)acrylate resin as in Example 2-5 is too large, it can be seen that the viscosity becomes higher. Furthermore, regarding the same use Polyfunctional and low-viscosity aromatic 6-functional urethane (meth)acrylate oligomers are used as examples 2-6~2-8 of urethane (meth)acrylate resin to obtain low A curable composition with high viscosity and high hardness.

In contrast, in Comparative Example 2-1 without urethane (meth)acrylate resin or Comparative Example 2-2 without epoxy (meth)acrylate resin, the solder heat resistance and gold plating resistance become Poor results. In addition, Comparative Example 2-3 that does not contain a bifunctional acrylate monomer has high viscosity and is not suitable for inkjet printing.

Claims (8)

A curable composition for inkjet, which is characterized by containing: (A) a urethane (meth)acrylate resin with 5 or more functions and 12 or less functions, (B) a photopolymerization initiator, and (C) Thermosetting compound with at least one thermoreactive functional group (excluding epoxy (meth)acrylate resin with at least one (meth)acrylic group), (D) with at least one (meth)acrylic group Epoxy (meth)acrylate resin and (E) bifunctional (meth)acrylate compound. The curable composition for inkjet according to claim 1, wherein the viscosity of the aforementioned (A) urethane (meth)acrylate resin at 25°C is 1,000 to 20,000 mPa. s. The curable composition for inkjet according to claim 1, wherein the aforementioned (C) thermosetting compound (excluding epoxy (meth)acrylate resin having at least one (meth)acrylic acid group) contains at least A first thermosetting compound having one (meth)acrylic acid group and at least one thermoreactive functional group, and a second thermosetting compound having at least two thermoreactive functional groups. The curable composition for inkjet according to claim 1, wherein the (D) epoxy (meth)acrylate resin is a bisphenol-type epoxy (meth)acrylate resin. The curable composition for inkjet according to claim 1, wherein the aforementioned (E) The bifunctional (meth)acrylate compound is a compound having an alkylene chain having 4 to 12 carbon atoms. For example, the curable composition for inkjet of claim 1, which has a viscosity of 50 mPa at 50°C. s or less. A cured coating film characterized by curing the curable composition for inkjet according to Claim 1. A printed circuit board characterized by having a hardened coating film as claimed in claim 7 on a substrate.