JP2006040935A - Photosetting/thermosetting matt solder resist ink composition and printed circuit board using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosetting/thermosetting matt solder resist ink composition which shows coating property excellent in aging stability, is excellent in heat resistance, chemical resistance and electrical insulation property and can alkaline develop without adherence of a solder powder to a coating film in contact with the solder without generating a solder bridge, etc., at a solder flow time and to provide a printed circuit board using the same. <P>SOLUTION: The photosetting/thermosetting matt solder resist ink composition contains (A) a carboxyl group-containing photosensitive resin obtained by reacting (a) a multi-functional epoxy resin with (b) an unsaturated monocarboxylic acid, or with (b) an unsaturated monocarboxylic acid and (e) a compound having at least one alcoholic hydroxide group and one reactive group except an alcoholic hydroxide to react with an epoxy group in the molecule, and further with (c) a saturated or unsaturated polybasic acid anhydride, (B) a photopolymerization initiator, (C) an organic filler, (D) a diluent, and (E) an epoxy resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photocurable and thermosetting matte solder resist ink composition that is useful for printed wiring board production, and more particularly, exhibits coating properties with excellent temporal stability, heat resistance, Excellent chemical resistance and electrical insulation, no solder bridging during solder flow, and no photodeposition of solder powder on the coating film due to contact with solder. The present invention relates to an eraser solder resist ink composition and a printed wiring board using the same.

Accompanying fine patterning of printed wiring boards in recent years, adhesion of solder on the resist film that occurs during solder flow is a major factor in causing defects such as bridges. In order to prevent this defect, the surface of the resist ink film is matted, which improves the resistance to solder adhesion on the resist ink film during solder flow, and is effective in suppressing the adhesion of the generated solder balls. It is known.
In forming such a matte resist film, a solder resist forming material using an inorganic filler such as an inorganic filler such as silica or aluminum silicate as a matting agent has been conventionally used (for example, patents). Reference 1).

However, when a hard inorganic filler such as silica or aluminum silicate is used as a matting agent, the printed wiring board on which the solder resist film is formed contacts other printed wiring boards because of its high hardness. When the solder resist film comes into contact with copper, solder, etc., the copper or solder is scraped off and the solder resist film is contaminated (referred to as solder powder). appear.
In order to solve such a problem, a method using talc, kaolin, and aluminum hydroxide having low hardness as a matting agent has been proposed (for example, see Patent Document 2).

However, when such talc, kaolin, aluminum hydroxide or the like is used as a matting agent, the chemical resistance is lowered, whitening or peeling occurs at the time of electroless gold plating, and the electrical insulation is lowered. Will occur. Further, due to the change with time, there is a problem that the wettability of the inorganic filler is improved and the matting effect is lost.
JP-A-9-157574 (Claims) JP 2003-295434 A (Claims)

  Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, and its main purpose is to exhibit coating properties with excellent stability over time, heat resistance, chemical resistance, and electrical insulation. A photo- and thermo-setting matte solder resist ink composition that is alkali-developable with no solder bridging during solder flow and no solder powder adheres to the coating film due to contact with the solder. It is to provide a printed wiring board using the same.

As a result of intensive studies to achieve the above object, according to the first aspect of the present invention, after (A) (a) a polyfunctional epoxy resin is reacted with (b) an unsaturated monocarboxylic acid, (c) ) A carboxyl group-containing photosensitive resin obtained by reacting a saturated or unsaturated polybasic acid anhydride, (B) a photopolymerization initiator, (C) an organic filler, (D) a diluent, and (E) an epoxy resin. An alkali-developable photocurable / thermosetting matte solder resist ink composition is provided.
Further, according to the second aspect of the present invention, (A ′) (a) a polyfunctional epoxy resin includes (b) an unsaturated monocarboic acid and (e) at least one alcoholic hydroxyl group and epoxy in one molecule. A carboxyl group-containing photosensitive resin obtained by reacting a compound having one reactive group other than an alcoholic hydroxyl group that reacts with a group, and further reacting with (c) a saturated or unsaturated polybasic acid anhydride, A photocurable and thermosetting matte solder resist ink composition containing (B) a photopolymerization initiator, (C) an organic filler, (D) a diluent, and (E) an epoxy resin is provided. Is done.
Furthermore, according to the third aspect of the present invention, the solder resist ink composition further includes (F) a carboxyl group-containing copolymer resin, and an alkali developable photocurable / thermosetting matte solder resist. An ink composition is provided.
Furthermore, as another aspect, the solder resist ink composition is composed of a solder resist film obtained by curing by active energy ray irradiation and / or heating, and the film surface has a 60 ° gloss value according to ATMS D 523-89. A printed wiring board having a resist film of 50 or less is provided.

Since the photocurable / thermosetting matte solder resist ink composition of the present invention exhibits stable coating properties over time, a stable solder resist film can be provided. In addition, it has excellent heat resistance, chemical resistance, and electrical insulation, and does not adhere to solder bridges or solder powder during solder flow, so it is excellent in productivity and contributes to a reduction in the defective rate when manufacturing printed wiring boards. The price can be reduced.
In addition, since it has excellent electrical insulation and no solder bridges, it is possible to increase the density of the circuit and to provide a highly reliable printed wiring board at a low price.

The basic aspect of the photocurable / thermosetting matte solder resist ink composition of the present invention is as follows: (A) (a) a polyfunctional epoxy resin is reacted with (b) an unsaturated monocarboxylic acid; (C) a carboxyl group-containing photosensitive resin obtained by reacting a saturated or unsaturated polybasic acid anhydride, or (A ′) (a) a polyfunctional epoxy resin, (b) an unsaturated monocarboxylic acid and (e) After reacting a compound having at least one alcoholic hydroxyl group and one reactive group other than the alcoholic hydroxyl group that reacts with an epoxy group in one molecule, (c) a saturated or unsaturated polybasic acid anhydride A composition containing (B) a photopolymerization initiator, (C) an organic filler, (D) a diluent, and (E) an epoxy resin can be alkali-developed to a carboxyl group-containing photosensitive resin obtained by reacting Light curing and heat It became a curable matte solder resist ink composition, and it was found that the adhesion of solder powder was eliminated by an organic filler having a relatively low hardness and a lubricant effect, and the present invention was completed.
As another aspect, the solder resist ink composition further contains (F) a carboxyl group-containing copolymer resin that is poorly compatible with the carboxyl group-containing photosensitive resin (A) or (A ′). The present inventors have found that the matte effect is further improved and have completed the present invention. As a suitable aspect of the said organic filler (C) used for such a mat | matte soldering resist ink composition, an average primary particle diameter exists in the range of 1-30 micrometers, and true specific gravity is 1.0-2.0. Furthermore, it is preferable that the refractive index of the organic filler (C) is in the range of 1.3 to 1.7 without causing appearance defects such as cloudiness.
Furthermore, as another aspect, ATMS D on the surface of a cured film comprising a solder resist film obtained by curing the photocurable / thermosetting matte solder resist ink composition by active energy ray irradiation and / or heating. The 60 ° gloss value according to 523-89 was found to be 50 or less, and the present invention was completed.

Below, each structural component of the photocurable and thermosetting matte solder resist ink composition of this invention is demonstrated in detail.
First, as the carboxyl group-containing photosensitive resin used in the present invention, (a) a polyfunctional epoxy resin is reacted with (b) an unsaturated monocarboxylic acid, and then (c) a saturated or unsaturated polybasic acid anhydride. A carboxyl group-containing photosensitive resin (A) obtained by reacting a product, or (a) a polyfunctional epoxy resin, (b) an unsaturated monocarboxylic acid and (e) at least one alcoholic hydroxyl group in one molecule; Carboxyl group-containing photosensitive resin obtained by reacting a compound having one reactive group other than an alcoholic hydroxyl group that reacts with an epoxy group, and further reacting with (c) a saturated or unsaturated polybasic acid anhydride (A ′) is used.
These carboxyl group-containing photosensitive resins can be used in combination with (A) or (A ′) alone, or resins having different molecular weights and structures derived from a plurality of raw materials.

As the polyfunctional epoxy resin (a), novolaks obtained by reacting phenols such as phenol, cresol, halogenated phenol and alkylphenol with formaldehyde in the presence of an acid catalyst are reacted with epihalohydrins such as epichlorohydrin and methyl epichlorohydrin. Trisphenol methane type epoxy obtained by reacting epihalohydrin such as epichlorohydrin or methyl epichlorohydrin with a novolak type epoxy resin obtained by reaction with a polyfunctional phenol compound obtained by reacting phenols with salicylaldehyde in the presence of an acid catalyst Resin, further bisphenol F type or bisphenol A type bifunctional epoxy compound is dissolved in a polar solvent such as dimethyl sulfoxide, and then epihalohydrin (for example, epichlorohydrin) Hydrin, etc.) and alkali metal hydroxides (e.g., by reacting sodium hydroxide and the like), such as multi-functionalized bisphenol skeleton resins.
As commercially available products, DEN-431, DEN-438, DEN-439 manufactured by Dow Chemical Company, RE-306, EPPN-201 manufactured by Nippon Kayaku Co., Ltd., Epicron N-730 manufactured by Dainippon Ink & Chemicals, Epoxylon N-770, phenol novolac type epoxy resin such as Epicoat 152 and Epicoat 154 manufactured by Japan Epoxy Resin; EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1020 and EOCN-1027 manufactured by Nippon Kayaku Co., Ltd. Epicron N-665, Epicron N-673, Epicron N-695, manufactured by Dainippon Ink and Chemicals, Inc. ESCN-195, manufactured by Sumitomo Chemical Co., Ltd., ECN-265, ECN-285, ECN-293, manufactured by Asahi Kasei Corporation ECN-299, YDCN-701, YD made by Toto Kasei Cresole novolac type epoxy resin such as CN-704; Trisphenol methane type epoxy such as EPPN-501 and EPPN-502 manufactured by Nippon Kayaku Co., Ltd., TACTIX 742 manufactured by Dow Chemical Co., and Epicoat 1032S50 manufactured by Japan Epoxy Resin Co., Ltd. Resins; Multifunctional bisphenol type epoxy resins such as NER-1302 and NER-7406 manufactured by Nippon Kayaku Co., Ltd. may be mentioned.

Examples of the unsaturated monocarboxylic acid (b) include acrylic acid, methacrylic acid, β-styrylacrylic acid, β-furfurylacrylic acid, crotonic acid, α-cyanocinnamic acid, cinnamic acid, β-carboxylethyl acrylate. And compounds obtained by adding a dibasic acid anhydride such as succinic acid to a hydroxyl group-containing (meth) acrylate such as 2-hydroxyethyl acrylate. Among these, photosensitivity, reactivity, and storage stability are included. From the aspect, acrylic acid or methacrylic acid is particularly preferable.
These unsaturated monocarboxylic acids (b) may be used alone or in admixture of two or more.
In addition, in this specification, (meth) acrylate is a term which generically refers to acrylate, methacrylate and mixtures thereof, and the same applies to other similar expressions.

Examples of the saturated or unsaturated polybasic acid anhydride (c) include maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydroanhydride. Phthalic acid, methylhexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, dodecenyl succinic anhydride, chlorendic anhydride, trimellitic anhydride, pyromellitic anhydride, 5- (2,5 -Dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, benzophenone tetracarboxylic acid anhydride, and the like, and these can be used alone or in combination of two or more. . Among these, alicyclic dibasic acids such as tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, etc. Anhydrides are particularly preferred from the viewpoints of developability and curability.
The addition amount of the saturated or unsaturated polybasic acid anhydride (c) is preferably in the range where the acid value of the carboxyl group-containing photosensitive resin is 60 to 120 mgKOH / g. When the acid value of the carboxyl group-containing photosensitive resin is less than 60 mgKOH / g, developability cannot be obtained, which is not preferable. On the other hand, when the acid value exceeds 120 mgKOH / g, coating properties such as plating resistance are deteriorated, which is not preferable.

  As the compound (e) having at least one alcoholic hydroxyl group and one reactive group other than the alcoholic hydroxyl group that reacts with an epoxy group in one molecule used in the carboxyl group-containing photosensitive resin (A ′). For example, polyhydroxymonocarboxylic acids such as dimethylolpropionic acid, dimethylolacetic acid, dimethylolbutyric acid, dimethylolvaleric acid, dimethylolcaproic acid; (bis) hydroxymethylphenol, hydroxymethyl-di-t-butylphenol, p-hydroxyphenyl -2-methanol, p-hydroxyphenyl-3-propanol, p-hydroxyphenyl-4-butanol, hydroxyethylcresol, 2,6-dimethyl-4-hydroxymethylphenol, 2,4-dihydroxymethyl-2-cyclohexylphenol , Trimethylolphenol, hydroxyalkylphenol or hydroxyalkylcresol such as 3,5-dimethyl-2,4,6-trihydroxymethylphenol; carboxyl group-containing substitution such as hydroxybenzoic acid, hydroxyphenylbenzoic acid, or hydroxyphenoxybenzoic acid Esterified product of phenol having a group and ethylene glycol, propylene glycol, glycerol, diethylene glycol, etc .; monoethylene oxide adduct of bisphenol, monopropylene oxide adduct of bisphenol; p-hydroxyphenethyl alcohol; diethanolamine, diisopropanolamine, etc. Examples thereof include dialkanolamines. Particularly preferable examples include dimethylolpropionic acid and p-hydroxyphenethyl alcohol.

When these compounds (e) are reacted with the polyfunctional epoxy resin (a) together with the unsaturated monocarboxylic acid (b), an alcoholic hydroxyl group is formed at the molecular end, and then the saturated or unsaturated polybasic acid anhydride is formed. By adding (c), a carboxylic acid can be formed at the molecular end, so that the reactivity is improved and development can be performed with a low acid value.
The amount of these compounds (e) used is 0.6 equivalents or less with respect to 1 equivalent of the epoxy group of the polyfunctional epoxy resin (a), and the total amount with the unsaturated monocarboxylic acid (b) is The range which becomes 0.95-1.1 equivalent with respect to 1 equivalent of epoxy groups of a polyfunctional epoxy resin (a) is preferable.

  Examples of the photopolymerization initiator (B) used in the present invention include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenyl Acetophenones such as acetophenone, 2,2-diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl]- Aminoacetophenones such as 2-morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; 2-methylanthraquinone, 2-ethylanthraquinone, 2- Tertiary Anthraquinones such as tilanthraquinone and 1-chloroanthraquinone; Thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone; Acetophenone dimethyl ketal, benzyldimethyl ketal, etc. Benzophenones such as benzophenone; or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, Phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and ethyl-2,4,6-trimethylbenzoylphenylphosphinate; It is like earth, may be used alone or in combination of two or more of these conventionally known photopolymerization initiator. The compounding quantity of these photoinitiators (B) is 0.2-10 mass% in all the compositions, Preferably it is 0.5-5 mass%. When the blending amount is less than 0.2% by mass of the total amount of the composition, the photocurability is lowered, and pattern formation after exposure / development becomes difficult. On the other hand, if it exceeds 10% by mass, the photo-radical polymerization initiator itself absorbs light, resulting in a decrease in thick film curability and high cost.

Along with the photopolymerization initiator (B) as described above, N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, triethanolamine, etc. Photosensitizers such as tertiary amines can be used alone or in combination of two or more.
Further, a titanocene photopolymerization initiator such as Irgacure 784 manufactured by Ciba Specialty Chemicals, which initiates radical polymerization in the visible region, a leuco dye, or the like can be used in combination as a curing aid.

The organic filler (C) used in the present invention is, for example, polyethylene, polypropylene, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, polycarbonate, crosslinked polymethyl methacrylate, crosslinked polybutyl methacrylate, Polyimide, polyamide, polyester, polyvinyl chloride, polyvinylidene chloride, polydivinylbenzene, fluorine resin, polyphenylene oxide, polyphenylene sulfide, polymethylpentene, urea resin, melamine resin, benzoguanamine resin, polyacetal resin, furan resin, silicone resin, epoxy Resin cured products and the like, particularly polyethylene, polypropylene, cross-linked polymethyl methacrylate, cross-linked polybutyl methacrylate and the like are preferably used. That.
These organic fillers (C) have an average primary particle size in the range of 1 to 30 μm, preferably 2 to 10. The true specific gravity of the organic filler (C) is 1.0 to 2.0, preferably 1.2 or less. When the average primary particle size is less than 1 μm, the matte effect is reduced, which is not preferable. On the other hand, when the average primary particle size exceeds 30 μm, pattern formation is deteriorated, or pinholes are generated due to dropping off of the organic filler after the coating film is formed. Further, when the true specific gravity of the organic filler (C) exceeds 2.0, it is not preferable because the organic filler (C) settles during storage or aggregates inside the coating film and does not show a matting effect. . On the other hand, when the true specific gravity is less than 1.0, it is not preferable because separation such as the organic filler (C) is easily raised on the ink surface.
Furthermore, it is preferable that the refractive index of the organic filler (C) is in the range of 1.3 to 1.7 without causing appearance defects such as cloudiness of the coating film.
Content of the said organic filler (C) is 0.01-20.0 mass% in the whole composition, Preferably it is 1.0-10 mass%. When the content of the organic filler (C) is 0.01% by mass or less, the matte effect of the cured coating film is lost, which is not preferable. On the other hand, if it exceeds 20.0% by mass, the heat resistance and the like are deteriorated and the appearance is deteriorated.
In addition, the photocurable / thermosetting matte solder resist ink composition of the present invention can be blended with an inorganic filler such as barium sulfate, finely divided silica, and talc, as long as there is no problem in properties.

The diluent (D) used in the present invention is used to adjust the viscosity of the composition to improve workability, and to increase the crosslink density or improve the adhesion, such as a photopolymerizable monomer. The reactive diluent (D-1) and a known and commonly used organic solvent (D-2) can be used.
Examples of the reactive diluent (D-1) include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) ) Hydroxyalkyl (meth) acrylates such as acrylates; Mono- or di (meth) acrylates of alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol; hexanediol, trimethylolpropane, pentaerythritol, ditrimethylol Polyhydric alcohols such as propane, dipentaerythritol, trishydroxyethyl isocyanurate, etc. or polyhydric (meta) of these ethylene oxide or propylene oxide adducts Acrylates: (Meth) acrylates of ethylene oxide or propylene oxide adducts of phenols such as phenoxyethyl (meth) acrylate and polyethoxydi (meth) acrylate of bisphenol A; glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, triglycidyl (Meth) acrylates of glycidyl ether such as isocyanurate; and melamine (meth) acrylate.
These can be used singly or in combination of two or more, (meth) acrylates containing a hydrophilic group in terms of liquid stability of the composition, and polyfunctional (meth) acrylates in terms of photocurability. Is preferred. The range of use of these photopolymerizable monomers is 20% by mass or less, preferably 10% by mass or less in the entire composition. If it is more than this, it is not preferable because the dryness to the touch becomes worse.

Examples of the organic solvent (D-2) include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methylcellosolve, butylcellosolve, carbitol, methylcarbitol, butylcarbi Toluene, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether and other glycol ethers; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl Carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether Seteto, esters such as propylene carbonate; octane, aliphatic hydrocarbons decane; petroleum ether, petroleum naphtha, and petroleum solvents such as solvent naphtha, organic solvents conventionally known can be used. These organic solvents can be used alone or in combination of two or more.
The amount of such an organic solvent varies depending on the coating method and the boiling point of the organic solvent to be used, and is not particularly limited. In general, the total amount of the organic solvent is 50% by mass, preferably 30% by mass. Or less, more preferably 20% by mass or less. When a high-boiling organic solvent is contained in a large amount, the dryness to the touch is lowered, and sagging or the like occurs after the coating until it is temporarily dried.

  The epoxy resin (E) used in the present invention includes various known and commonly used epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, brominated bisphenol A type epoxy resins, and hydrogenated bisphenol A. Type epoxy resin, biphenol type epoxy resin, bixylenol type epoxy resin, phenol novolac type epoxy resin, cresol novolak type epoxy resin, brominated phenol novolak type epoxy resin, bisphenol A novolak type epoxy resin, trihydroxyphenylmethane type epoxy resin , Tetraphenylol ethane type epoxy resin, phenol novolac type epoxy resin containing naphthalene skeleton, phenol novolak type epoxy resin containing dicyclopentadiene skeleton, etc. Glycidyl ether compounds; glycidyl ester compounds such as terephthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, dimer acid diglycidyl ester; alicyclic epoxy resins such as EHPE-3150 manufactured by Daicel Chemical Industries; Heterocyclic epoxy resins such as N, N, N ′, N′-tetraglycidylmetaxylenediamine, N, N, N ′, N′-tetraglycidylbisaminomethylcyclohexane, N, N-diglycidylaniline, etc. Known and commonly used epoxy compounds such as glycidylamines and copolymers of glycidyl (meth) acrylate and compounds having an ethylenically unsaturated double bond can be used. From the viewpoint of dryness to the touch and heat resistance, phenol Novolac epoxy resin, Cresor Novolak type epoxy resins, biphenol-type or bixylenol type epoxy resin or a mixture thereof and triglycidyl isocyanurate is particularly preferred. These epoxy resins (E) can be used alone or in combination of two or more.

  These epoxy resins (E) are thermally cured with the carboxyl group-containing photosensitive resin (A) or (A ′) to improve heat resistance, adhesion, and the like. The compounding amount of these epoxy resins (E) is 0.8 to 2.0 equivalents of epoxy groups, preferably 1.0 to 1 with respect to 1 equivalent of carboxyl groups of the carboxyl group-containing photosensitive resin (A). .8 equivalents. When the blending amount of the epoxy resin (E) is less than 0.8 equivalent of an epoxy group, an unreacted carboxyl group remains, the hygroscopic property of the cured film is increased, and the PCT resistance is easily lowered. And electroless plating resistance tend to be low. Moreover, when the compounding quantity of an epoxy resin (E) exceeds 2.0 equivalent of epoxy groups, the developability of a coating film and the electroless-plating resistance of a cured film will deteriorate, and PCT resistance will also be inferior. .

In order to further enhance the matting effect, a carboxyl group-containing copolymer resin (F) can be added to the photocurable / thermosetting matte solder resist ink composition of the present invention.
As the carboxyl group-containing copolymer resin (F), a copolymer resin having a carboxyl group in the molecule, or a photosensitive carboxyl group-containing copolymer resin having an ethylenically unsaturated bond in the molecule can be used. Specific examples include the resins listed below.
(F-1) a carboxyl group-containing copolymer resin obtained by copolymerization of an unsaturated carboxylic acid and another compound having an unsaturated double bond;
(F-2) An epoxy group-containing unsaturated compound (such as glycidyl methacrylate) is partially added to the carboxyl group of a copolymer resin of an unsaturated carboxylic acid and a compound having an unsaturated double bond other than that. A photosensitive carboxyl group-containing copolymer resin obtained by
(F-3) An unsaturated monocarboxylic acid is reacted with a copolymer resin of an epoxy group-containing unsaturated compound (for example, glycidyl methacrylate) and another compound having an unsaturated double bond, and further saturated or Examples include, but are not limited to, photosensitive carboxyl group-containing copolymer resins obtained by reacting unsaturated polybasic acid anhydrides.
Since the carboxyl group-containing copolymer resin (F) as described above has a large number of free carboxyl groups in the side chain of the backbone polymer, it does not deteriorate developability with a dilute aqueous alkali solution, and the polyfunctional Since the compatibility with the carboxyl group-containing photosensitive resin (A) or (A ′) derived from the epoxy resin is poor, the matte effect can be increased.

The acid value of such a carboxyl group-containing copolymer resin (F) is in the range of 40 to 200 mgKOH / g, more preferably in the range of 80 to 120 mgKOH / g. If the acid value of the carboxyl group-containing copolymer resin (F) is less than 40 mgKOH / g, the alkali developability is lowered, and an undeveloped image may be generated. On the other hand, if it exceeds 200 mgKOH / g, the development resistance of the exposed area is lowered, which is not preferable.
Moreover, the weight average molecular weight of such a carboxyl group-containing copolymer resin (F) is 2,000 to 50,000, preferably 5,000 to 20,000. When the weight average molecular weight is less than 2,000, the compatibility with the carboxyl group-containing photosensitive resin (A) or (A ′) derived from the polyfunctional epoxy resin is improved, and the matte improving effect is lost. Absent. On the other hand, when the weight average molecular weight exceeds 50,000, the developability is lowered, which is not preferable.

The photocurable / thermosetting matte solder resist ink composition of the present invention can be colored with an inorganic pigment, an organic pigment, an organic dye, or the like, if necessary, but the organic dye causes a decrease in sensitivity. Because of this, it is preferable to use inorganic pigments or organic pigments. Specific examples include phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black. Furthermore, it is preferable to use a non-halogen organic pigment (F) in view of environmental problems.
The amount of these pigments is generally 5% by mass or less in the composition, excluding titanium oxide. When it is more than the above range, the photocurability is lowered, which is not preferable. In addition, when using a titanium oxide, generally it is used at 15 mass% or less in a composition.

  Furthermore, the photocurable / thermosetting matte solder resist ink composition of the present invention can contain imidazole salts, boron trifluoride complexes, organometallic salts and the like as latent curing catalysts. Further, for the purpose of preventing the oxidation of copper, i.e., copper, a compound such as adenine, vinyltriazine, dicyandiamide, orthotolylbiguanide, melamine, or a salt thereof can be added. The compounding ratio of these compounds is generally 5% by mass or less in the composition, and by adding these, the chemical resistance of the cured coating film and the adhesion to the copper foil are improved.

  Furthermore, the photocurable / thermosetting matte solder resist ink composition of the present invention is within a range that does not deteriorate the coating film properties, and if necessary, hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, pyrogallol, Known conventional thermal polymerization inhibitors such as phenothiazine, antifoaming agents and / or leveling agents such as silicones, fluorines and polymers, and silane coupling agents such as imidazole, thiazole and triazole. Conventional additives can be blended.

The photocurable / thermosetting matte solder resist ink composition of the present invention having the above composition is diluted as necessary to adjust the viscosity to be suitable for the coating method. By applying to the printed wiring board by a method such as screen printing, curtain coating, play coating, roll coating, etc., and evaporating and drying an organic solvent contained in the composition at a temperature of 60 to 100 ° C., for example. A tack-free coating film can be formed.
Thereafter, it can be selectively exposed with active energy rays through a photomask having a predetermined pattern, and the unexposed portion can be developed with a dilute alkaline aqueous solution to form a resist pattern. Adhesion, hardness, solder heat resistance, chemical resistance, solvent resistance, electrical insulation, electrical corrosion resistance by irradiation with active energy rays after heat curing or final finish curing (main curing) only by heat curing A cured film (solder resist film) excellent in resolution, plating resistance, PCT resistance, and moisture absorption resistance is formed.
The cured film thus obtained has a 60 ° gloss value of 50 or less according to ATMS D 523-89, and it is difficult for solder to adhere to the cured film.
In the case of a cured film having a gloss value exceeding 50, it is not preferable because solder tends to adhere to the cured film.

  As the alkaline aqueous solution used for the development, alkaline aqueous solutions such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines and the like can be used. As the irradiation light source for photocuring, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like is appropriate. In addition, laser beams and the like can also be used as active energy rays.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, it cannot be overemphasized that this invention is not limited to the following Example. In the following description, “part” means “part by mass” unless otherwise specified.

Synthesis example 1
215 parts of cresol novolac type epoxy resin N-680 (Dainippon Ink Chemical Co., Ltd., epoxy equivalent = 215) was placed in a four-necked flask equipped with a stirrer and reflux condenser, and 97.5 parts of carbitol acetate was added. In addition, it was dissolved by heating. Next, 0.46 parts of methylhydroquinone as a polymerization inhibitor and 1.38 parts of triphenylphosphine as a reaction catalyst were added. This mixture was heated to 95-105 ° C., 72.0 parts (1.0 equivalent) of acrylic acid was gradually added dropwise and reacted for about 24 hours to obtain a reaction product having an acid value of 0.9 mgKOH / g. . The reaction product (hydroxyl group: 1 equivalent) was cooled to 80 to 90 ° C., 76.0 parts (0.5 equivalent) of tetrahydrophthalic anhydride was added, and the reaction was allowed to proceed for about 8 hours. To this reaction solution, 97.7 parts of the aromatic solvent ipsol # 150 manufactured by Idemitsu Petrochemical Co., Ltd. was added, diluted, and taken out. The carboxyl group-containing photosensitive resin (A) thus obtained had a non-volatile content of 65% and a solid acid value of 77 mgKOH / g. Hereinafter, this varnish is referred to as A-1 varnish.

Synthesis example 2
215 parts of cresol novolac type epoxy resin N-680 (Dainippon Ink Chemical Co., Ltd., epoxy equivalent = 215) was placed in a four-necked flask equipped with a stirrer and a reflux condenser, and 152.5 parts of carbitol acetate was added. In addition, it was dissolved by heating. Next, 0.46 parts of methylhydroquinone as a polymerization inhibitor and 1.38 parts of triphenylphosphine as a reaction catalyst were added. This mixture was heated to 95-105 ° C., 57.6 parts (0.8 equivalents) of acrylic acid and 26.8 parts (0.2 equivalents) of dimethylolpropionic acid were gradually added dropwise and reacted for about 24 hours. A reaction product having an acid value of 0.9 mgKOH / g was obtained. The reaction product was cooled to 80 to 90 ° C., 60.8 parts (0.4 equivalent) of tetrahydrophthalic anhydride was added, allowed to react for 8 hours, cooled, and taken out. The carboxyl group-containing photosensitive resin (A ′) thus obtained had a nonvolatile content of 62% and a solid acid value of 64 mgKOH / g. Hereinafter, this varnish is referred to as A-2 varnish.

Synthesis example 3
A flask equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser was charged with 276.0 g of dipropylene glycol monomethyl ale as a solvent and 8.2 g of azobisisobutyronitrile as a polymerization catalyst. In a nitrogen atmosphere, the mixture was heated to 60 ° C., and a monomer mixed with 172.0 g of methacrylic acid and 100.0 g of methyl methacrylate was added dropwise over about 3 hours. After further stirring for 1 hour, the temperature was raised to 115 ° C. The catalyst was deactivated.
After the reaction solution was lowered to 85-95 ° C., 0.3 g of methylhydroquinone as a polymerization inhibitor and 2.0 g of triphenylphosphine as a catalyst were added, and 142.0 g of glycidyl methacrylate was gradually added dropwise to react for about 24 hours. I let you. The thus obtained photosensitive carboxyl group-containing copolymer resin (F) has a weight average molecular weight of 16,000, a non-volatile content of 60%, and a solid acid value of 135.6 mgKOH / g. there were. Hereinafter, this reaction solution is referred to as F varnish.

Examples 1-8 and Comparative Examples 1-3
Using each varnish obtained in Synthesis Examples 1 to 3, the components are blended in the blending ratios shown in Table 1 below, kneaded using a three-roll mill, and a photocurable / thermosetting solder resist ink composition. Was prepared. In addition, it diluted with the organic solvent as needed at the time of printing.

  About each photocurable and thermosetting soldering resist ink composition of the said Examples 1-8 and Comparative Examples 1-3, it tested about each following item and evaluated. In addition, each of the above-mentioned photocurable and thermosetting solder resist ink compositions was similarly evaluated for each item after adjustment and after storage at room temperature for 2 months. The results are shown in Table 2.

(1) Printability Each of the photocurable / thermosetting solder resist ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 is printed on a substrate of an IPC standard, B package (made by Ceria Corporation). ) Was applied to the entire surface with a PET 100 mesh screen. Then, it hardened | cured for 150 minutes at 150 degreeC with the hot-air circulation type drying furnace. The circuit between the cured films was observed using an optical microscope (magnification 30 times), and the bubble generation state and the print skip generation state were evaluated according to the following criteria.
Occurrence state of bubbles: Good: No bubbles are observed.
Δ: Some bubbles are observed.
X: A bubble is recognized remarkably.
Occurrence state of skip ○: Skip is not recognized and good.
Δ: Some skipping is recognized.
X: Skip is remarkably recognized.

(2) Appearance (cloudiness)
The appearance of each of the above substrates was visually evaluated according to the following criteria.
○: Turbidity is not seen.
Δ: Some turbidity.
X: It is cloudy.

(3) Gloss In the same manner as described above, each photocurable / thermosetting solder resist ink composition was applied on the entire surface of the copper foil substrate by screen printing. This was dried for a while to form a tack-free coating film. A negative film was applied to the substrate, exposed in accordance with a predetermined pattern, and developed with a 1 wt% Na2CO3 aqueous solution having a spray pressure of 0.2 MPa to form a pattern. This substrate was heat-cured at 150 ° C. for 60 minutes in a hot air circulation drying oven to prepare a test substrate. Five test substrates were prepared, and the surface was measured for 60-degree specular reflectance using microtrigloss (manufactured by Big Chemie Japan). The 60-degree specular reflectivity was rounded off to the first decimal place and displayed as an integer.

(4) Solder adhesion to the coating (presence of solder balls)
In the same manner as described above, each photo-curable / thermosetting solder resist ink composition is applied on the entire surface of the circuit-formed substrate by screen printing and dried at 80 ° C. for 30 minutes in a hot-air circulating drying oven. A tack-free coating film was formed. A negative film was applied to the substrate, exposed according to a predetermined pattern, and developed with a 1 wt% Na ₂ CO ₃ aqueous solution having a spray pressure of 0.2 MPa to form a pattern. This substrate was heat-cured at 150 ° C. for 60 minutes in a hot air circulation drying oven to prepare a test substrate. The test substrate thus prepared was subjected to a soldering temperature of 260 ° C., a double wave, and a conveyor speed of 1.4 m in the air without using a flow soldering apparatus (manufactured by Tokyo Production Engineering Co., Ltd.). Solder flow was performed at a rate of 1 minute, and the adhesion of the solder to the resist film surface was visually observed and evaluated according to the following criteria.
○: Good with no adhesion of solder.
X: Adhesion of spine-shaped or cobweb-shaped solder is observed.

(5) Presence / absence of solder powder In the same manner as described above, two test substrates using each photocurable and thermosetting solder resist ink composition were prepared. The soldering surfaces of the two test boards were put together, rubbed under a certain load, and the presence or absence of solder powder adhered to the coating film surface was evaluated according to the following criteria.
○: No adhesion of solder powder is observed.
Δ: Some adhesion of solder powder is observed.
X: Remarkable adhesion of solder powder is recognized.

(6) Solder heat resistance In the same manner as described above, a test substrate using each photocurable and thermosetting solder resist ink composition was prepared. After applying rosin-based flux to each test substrate, it was immersed in a solder bath at 260 ° C. for 30 seconds. After the substrate was washed with propylene glycol menomotyl ether, the state of the coating film was evaluated according to the following criteria.
○: No abnormality such as swelling, peeling or discoloration of the coating film.
Δ: Slight swelling, peeling, discoloration, etc. are observed.
X: Remarkable blistering, peeling, discoloration, etc. are observed.

(7) Resistance to electroless gold plating In the same manner as described above, a test substrate using each photocurable and thermosetting solder resist ink composition was prepared. Each test substrate was degreased by immersing it in an acidic degreasing solution at 30 ° C. (manufactured by Nippon MacDermid Co., Ltd., 20 vol% aqueous solution of Metex L-5B), and then immersed in running water for 3 minutes and washed with water. This test substrate was immersed in a 14.3 wt% ammonium persulfate aqueous solution at room temperature for 3 minutes, subjected to soft etching, and then immersed in running water for 3 minutes to be washed with water. The test substrate was immersed in a 10 vol% sulfuric acid aqueous solution at room temperature for 1 minute, and then immersed in running water for 30 seconds to 1 minute and washed with water. This test substrate was immersed for 7 minutes in a 30 ° C. catalyst solution (manufactured by Meltex Co., Ltd., 10 vol% aqueous solution of metal plate activator 350), applied with a catalyst, then immersed in running water for 3 minutes and washed with water. . The test substrate to which the catalyst was applied was immersed in a nickel plating solution (manufactured by Meltex Co., Ltd., Melvol Ni-865M, 20 vol% aqueous solution, pH 4.6) for 20 minutes to perform electroless nickel plating. It was. The test substrate was immersed in a 10 vol% sulfuric acid aqueous solution at room temperature for 1 minute, and then immersed in running water for 30 seconds to 1 minute and washed with water. Next, after electroless gold plating was performed by immersing the test substrate in a gold plating solution at 95 ° C. (made by Meltex Co., Ltd., an aqueous solution of Ourolectroles UP 15 vol% and 3 vol% potassium cyanide, pH 6) for 10 minutes. It was immersed in running water for 3 minutes and washed with water, and further immersed in warm water at 60 ° C. for 3 minutes and washed with hot water. After sufficiently washing with water, water was thoroughly drained, dried, and an electroless gold plated test substrate was obtained. Using the electroless gold-plated substrate as described above, a peel test using a cellophane adhesive tape was performed, and peeling and discoloration of the coating film were evaluated according to the following criteria.
○: No change is observed at all.
(Triangle | delta): The coating film peeled off only slightly or discoloration was recognized.
X: Peeling is recognized on the coating film.

(8) HAST test In the same manner as above, each photocurable / thermosetting solder resist ink composition was applied to the entire surface of the IPC standard, B package substrate by screen printing. The film was dried at 80 ° C. for 30 minutes to form a tack-free coating film. A negative film was applied to the substrate, exposed in accordance with a predetermined pattern, and developed with a 1 wt% Na2CO3 aqueous solution having a spray pressure of 0.2 MPa to form a pattern. This substrate was heat-cured at 150 ° C. for 60 minutes in a hot air circulation drying oven to prepare a test substrate. This test substrate was placed in a high-temperature and high-humidity tank at 85 ° C. and a humidity of 90%, charged with a voltage of 100 V, and subjected to a HAST test for 7 days. The substrate after the HAST test was observed using an optical microscope (magnification 30 times) and evaluated according to the following criteria.
○: No abnormality such as discoloration is observed in the coating film.
Δ: Slight discoloration such as black spots is observed in the coating film.
X: Significant discoloration or swelling is observed in the coating film.

As is clear from Table 2, the examples using the organic filler have a sufficient matting effect, excellent electroless gold plating resistance, etc., and excellent temporal stability. However, the comparative example 1 matted with the talc of the inorganic filler has an insufficient matting effect, and the electroless gold plating resistance is also lowered. On the other hand, Comparative Examples 2 and 3 using aluminum hydroxide as an inorganic filler had a sufficient matting effect, but adhesion of solder powder was observed and the HAST test resistance was poor.

Claims (8)

(A) A carboxyl group-containing photosensitive resin obtained by reacting (a) a polyfunctional epoxy resin with (b) an unsaturated monocarboxylic acid and then further reacting with (c) a saturated or unsaturated polybasic acid anhydride. (B) a photopolymerization initiator, (C) an organic filler, (D) a diluent, and (E) an epoxy resin, a photocurable / thermosetting matte solder resist ink composition . (A ′) (a) a polyfunctional epoxy resin, (b) an unsaturated monocarboxylic acid, and (e) one reaction other than an alcoholic hydroxyl group that reacts with at least one alcoholic hydroxyl group and an epoxy group in one molecule. (C) a carboxyl group-containing photosensitive resin obtained by reacting a compound having a functional group and then reacting with a saturated or unsaturated polybasic acid anhydride, (B) a photopolymerization initiator, and (C) an organic filler. A photocurable / thermosetting matte solder resist ink composition comprising: (D) a diluent and (E) an epoxy resin. The average primary particle size of the organic filler (C) is in the range of 1 to 30 µm, and the true specific gravity is 1.0 to 2.0. Thermosetting matte solder resist ink composition. The photocurable / thermosetting matte according to any one of claims 1 to 3, wherein the refractive index of the organic filler (C) is in the range of 1.3 to 1.7. Solder resist ink composition. Content of the said organic filler (C) is 0.01-20.0 mass% in all the compositions, The photocurable and heat | fever as described in any one of Claims 1 thru | or 4 characterized by the above-mentioned. A curable matte solder resist ink composition. The photocurable / thermosetting matte solder resist ink composition according to any one of claims 1 to 5, further comprising (F) a carboxyl group-containing copolymer resin. The carboxyl group-containing copolymer resin (F) is (f-1) a copolymer resin of an unsaturated carboxylic acid and another compound having an unsaturated double bond, (f-2) an unsaturated carboxylic acid and the others A photosensitive carboxyl group-containing copolymer resin obtained by reacting an epoxy group-containing unsaturated compound with a carboxyl group of a compound resin having an unsaturated double bond, (f-3) an epoxy group-containing unsaturated group Contains a photosensitive carboxyl group obtained by reacting a copolymer of a compound and other compound having an unsaturated double bond with an unsaturated monocarboxylic acid and further reacting with a saturated or unsaturated polybasic acid anhydride. 7. The photocurable / thermosetting matte solder resist ink composition according to claim 6, wherein the composition is at least one resin selected from the group consisting of copolymer resins. It consists of a solder resist film obtained by hardening the solder resist ink composition according to any one of claims 1 to 7 by irradiation with active energy rays and / or heating, and 60 according to ATMS D 523-89 on the surface of the film. A printed wiring board, wherein a resist film having a gloss value of 50 or less is formed.