KR20150063927A - Photosensitive resin composition, dry film, cured product and printed wiring board - Google Patents

Abstract

Provided in the present invention are a photosensitive resin composition solving solubility problem of a photopolymerization initiator, a dry film, a cured product, and a printed wire board. The present invention relates to a photosensitive resin composition including (A) a carboxylic group-containing resin, (B) a thermosetting component, (C) an inorganic filler, and (D) a photopolymerization initiator, wherein (D) the photopolymerization initiator contains (D1) a bis acyl phosphine oxide-based initiator, and (D2) a hydroxy aceto phenone-based photopolymerization initiator.

Description

TECHNICAL FIELD [0001] The present invention relates to a photosensitive resin composition, a dry film, a cured product, and a printed wiring board,

The present invention relates to a photosensitive resin composition (hereinafter simply referred to as a "composition"), a dry film, a cured product and a printed wiring board, and more particularly to an alkali developing photosensitive resin composition, a dry film, And a printed wiring board.

Generally, a printed wiring board is formed by removing an unnecessary portion of a copper foil bonded to a laminate by etching to form a circuit wiring, and the electronic component is disposed at a predetermined place by soldering. In such a printed wiring board, a protective film for preventing adhesion of solder to a necessary portion and for preventing the conductor of the circuit from being exposed and being corroded by oxidation or moisture, A solder resist is formed in the region. Since the solder resist also functions as a permanent protective film of the circuit board, the solder resist is required to have various performances such as adhesiveness, electrical insulation, solder heat resistance, solvent resistance, and chemical resistance.

As a method of forming a solder resist of a desired pattern on a substrate, a forming method using a photolithography technique is used. For example, a photosensitive solder resist containing an alkali developing type photosensitive resin composition is exposed through a pattern mask and then subjected to alkali development to obtain a pattern using a difference in solubility in an alkali developing solution generated in the exposed portion and non- .

For example, Patent Document 1 discloses a solder resist composition containing a white pigment and capable of forming a solder resist layer having high light reflectivity while suppressing the amount of light necessary for exposure. In order to provide a solder resist composition containing a photosensitive resin, a white pigment , A photopolymerization initiator which is activated by light having a wavelength of 400 nm or more, and a fluorescent dye. In the examples of Patent Document 1, specifically, it is disclosed that a combination of 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 1-hydroxy-cyclohexyl-phenyl-ketone is used as a photopolymerization initiator.

Japanese Patent Laid-Open Publication No. 2011-227343 (claims)

Thus, it is known to use an acylphosphine oxide photopolymerization initiator for a solder resist. Among them, bisacylphosphine oxides are superior to monoacylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide used in Patent Document 1, and are suitable for solder resists. However, bisacylphosphine oxides have poor solubility in solvents, and as a result, sufficient photocuring properties can not be obtained at the time of exposure.

It is an object of the present invention to provide a photosensitive resin composition, a dry film, a cured product and a printed wiring board which solve the solubility problem of a photopolymerization initiator and have excellent photocurability.

The present inventors have intensively studied and, as a result, have found that, by using a hydroxyacetophenone-based photopolymerization initiator together with a bisacylphosphine oxide-based photopolymerization initiator as a photopolymerization initiator, the hydroxyacetophenone-based photopolymerization initiator improves the solubility of the bisacylphosphine oxide And as a result, it becomes possible to obtain good photo-curability. Thus, the present invention has been accomplished.

That is, the photosensitive resin composition of the present invention is a photosensitive resin composition containing (A) a carboxyl group-containing resin, (B) a thermosetting component, (C) an inorganic filler and (D) a photopolymerization initiator,

Wherein the photopolymerization initiator (D) comprises a bisacylphosphine oxide photopolymerization initiator (D1) and a hydroxyacetophenone photopolymerization initiator (D2).

In the composition of the present invention, it is preferable that the thermosetting component (B) contains at least one resin having no aromatic ring. Further, in the composition of the present invention, it is preferable that the inorganic filler (C) contains titanium oxide. In the composition of the present invention, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide may be suitably used as the bisacrylphosphine oxide photopolymerization initiator (D1).

The dry film of the present invention is characterized by having a resin layer obtained by applying and drying the photosensitive resin composition of the present invention on a carrier film.

The cured product of the present invention is obtained by curing the resin layer of the photosensitive resin composition of the present invention or the dry film of the present invention by light irradiation.

Further, the printed wiring board of the present invention is characterized by having the cured product of the present invention.

According to the present invention, with the above-described constitution, the problem of solubility of the photopolymerization initiator is solved, and it becomes possible to realize a photosensitive resin composition, a dry film, a cured product and a printed wiring board excellent in photocurability.

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

First, each component of the photosensitive resin composition of the present invention will be described. Further, in the present specification, (meth) acrylate is a generic term for acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.

[(A) Resin containing a carboxyl group]

The photosensitive resin composition of the present invention contains (A) a carboxyl group-containing resin. As the carboxyl group-containing resin (A), a resin containing a known carboxyl group can be used. By the presence of a carboxyl group, the composition can be made alkali-developable. In addition, from the viewpoint of making the composition of the present invention photo-curable and having an excellent developing property, it is preferable to have an ethylenically unsaturated bond in the molecule other than the carboxyl group, but only a carboxyl group-containing water not having an ethylenically unsaturated double bond may be used. The carboxyl group-containing resin (A) may or may not have an aromatic ring. (A) when the carboxyl group-containing resin has an aromatic ring, an effect of suppressing deterioration due to heat or light is obtained.

Specific examples of the carboxyl group-containing resin that can be used in the composition of the present invention include the following compounds (any of oligomers and polymers) listed below.

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene,? -Methylstyrene, lower alkyl (meth) acrylate or isobutylene. When the carboxyl group-containing resin has an aromatic ring, at least one of the unsaturated carboxylic acid and the unsaturated group-containing compound may have an aromatic ring.

(2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates, carboxyl-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, and polycarbonate-based polyols, polyether Containing carboxyl groups in a diol compound such as polyol, polyol, polyester polyol, polyolefin polyol, acrylic polyol, bisphenol A alkylene oxide adduct diol, phenolic hydroxyl group and alcoholic hydroxyl group. Urethane resin. When the carboxyl group-containing urethane resin has an aromatic ring, it may have at least one aromatic ring selected from a diisocyanate, a carboxyl group-containing dialcohol compound and a diol compound.

(3) A process for producing a polyisocyanate compound, which comprises reacting a diisocyanate compound such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate or an aromatic diisocyanate with a polycarbonate-based polyol, a polyether- , A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride at the terminal of a urethane resin by a heavy-chain reaction of a diol compound such as a bisphenol A-based alkylene oxide adduct diol, a phenolic hydroxyl group and a compound having an alcoholic hydroxyl group . When the carboxyl group-containing urethane resin has an aromatic ring, at least one of the diisocyanate compound, the diol compound and the acid anhydride may have an aromatic ring.

(4) a bifunctional epoxy resin such as a bisphenol A type epoxy resin, a hydrogenated bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a beccylenol type epoxy resin and a biphenol type epoxy resin (Meth) acrylate or a partial acid anhydride thereof, a carboxyl group-containing dialcohol compound and a diol compound. When the photosensitive carboxyl group-containing urethane resin has an aromatic ring, at least one of the diisocyanate, the (meth) acrylate of the bifunctional epoxy resin or the partial acid anhydride modification thereof, the carboxyl group-containing dialcohol compound and the diol compound has an aromatic ring do.

(5) During the synthesis of the resin of the above (2) or (4), a compound having one hydroxyl group and at least one (meth) acryloyl group in the molecule such as hydroxyalkyl (meth) (Meth) acrylated carboxyl group-containing urethane resin. When the photosensitive carboxyl group-containing urethane resin has an aromatic ring, a compound having one hydroxyl group and at least one (meth) acryloyl group in the molecule may have an aromatic ring.

(6) In the synthesis of the resin of the above (2) or (4), it is preferable to use a mixture of isophorone diisocyanate and pentaerythritol triacrylate, such as equimolar reactants, having one isocyanate group and at least one (meth) acryloyl group in the molecule (Meth) acrylated carboxyl group-containing urethane resin by adding a compound. When the photosensitive carboxyl group-containing urethane resin has an aromatic ring, a compound having one isocyanate group and at least one (meth) acryloyl group in the molecule may have an aromatic ring.

(7) A photosensitive carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with (meth) acrylic acid and adding a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to a hydroxyl group present in the side chain. When the photosensitive carboxyl-containing resin has an aromatic ring, at least one of the polyfunctional epoxy resin and the dibasic acid anhydride may contain an aromatic ring.

(8) A photosensitive carboxyl group-containing resin obtained by reacting a (meth) acrylic acid with a polyfunctional epoxy resin obtained by epoxidizing a hydroxyl group of a bifunctional epoxy resin with epichlorohydrin and adding a dibasic acid anhydride to the resulting hydroxyl group. When the photosensitive carboxyl group-containing resin has an aromatic ring, at least one of the bifunctional epoxy resin and the dibasic acid anhydride may have an aromatic ring.

(9) A carboxyl group-containing polyester resin in which a dibasic acid anhydride is added to a primary hydroxyl group generated by reacting a polycarboxylic acid with a polyfunctional oxetane resin. When the photosensitive carboxyl group-containing polyester resin has an aromatic ring, at least one of the polyfunctional oxetane resin, dicarboxylic acid and dibasic acid anhydride may contain an aromatic ring.

(10) A reaction product obtained by reacting a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in a molecule with an alkylene oxide such as ethylene oxide or propylene oxide, with a monocarboxylic acid containing an unsaturated group is reacted with a polybasic acid anhydride To obtain a carboxyl group-containing photosensitive resin.

(11) A reaction obtained by reacting a compound having a plurality of phenolic hydroxyl groups in a molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate to react with a monocarboxylic acid containing an unsaturated group A photosensitive resin containing a carboxyl group obtained by reacting a product with a polybasic acid anhydride.

(12) A process for producing an epoxy compound having a plurality of epoxy groups in a molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol, and a compound having an unsaturated (meth) Containing carboxylic acid anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride and adipic acid to the alcoholic hydroxyl group of the reaction product obtained by reacting a carboxylic acid group-containing monocarboxylic acid Containing photosensitive resin. When the photosensitive carboxyl group-containing polyester resin has an aromatic ring, at least one of the epoxy compound, the compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, the unsaturated group-containing monocarboxylic acid and the polybasic acid anhydride, You just need a ring.

(13) The resin composition according to any one of the above items (1) to (12), further comprising one or more epoxy groups in the molecule such as glycidyl (meth) acrylate and? -Methyl glycidyl (meth) Meth) acryloyl group is added to the photosensitive resin composition. When the photosensitive carboxyl group-containing urethane resin has an aromatic ring, a compound having one epoxy group and at least one (meth) acryloyl group in the molecule may have an aromatic ring.

Since the carboxyl group-containing resin has a large number of carboxyl groups in the side chain of the backbone polymer, development with a dilute aqueous alkali solution becomes possible.

The acid value of the carboxyl group-containing resin is preferably in the range of 20 to 200 mgKOH / g, more preferably 40 to 180 mgKOH / g. If it is in the range of 20 to 200 mgKOH / g, the adhesion of the coating film is obtained, the alkali development is facilitated, the dissolution of the exposed portion by the developer is suppressed, the line is not thinned more than necessary, Which is preferable.

The weight average molecular weight of the carboxyl group-containing resin used in the present invention varies depending on the resin skeleton, but is preferably in the range of 2,000 to 150,000. Within this range, the tack-free performance is good, the wettability of the coating film after exposure is good, and the film is hardly reduced at the time of development. When the weight average molecular weight is in the above range, the resolution is improved, the developing property is good, and the storage stability is improved. More preferably, it is from 5,000 to 100,000. The weight average molecular weight can be measured by gel permeation chromatography.

[(B) Thermosetting component]

In the photosensitive resin composition of the present invention, a thermosetting component (B) is added to impart heat resistance. As the thermosetting component (B), any known thermosetting component may be used as long as it is used as a thermosetting component in the thermosetting resin composition. Examples of the thermosetting component (B) include an isocyanate compound, a block isocyanate compound, an amino resin, a maleimide compound, a benzoxazine resin, a carbodiimide resin, a cyclocarbonate compound, a polyfunctional epoxy compound, a polyfunctional oxetane compound, And a thermosetting resin for a known purpose such as a feed resin can be used.

Among them, the preferred thermosetting component is a thermosetting component having at least one of a plurality of cyclic ether groups and cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in one molecule. These thermosetting components having a cyclic (thio) ether group have many kinds of commercially available products and can impart various properties depending on the structure thereof.

The thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is a compound having a plurality of one or two kinds of groups of a cyclic ether group or a cyclic thioether group of 3, 4 or 5-membered rings in the molecule, Namely, a compound having a plurality of epoxy groups, that is, a polyfunctional epoxy compound, a compound having a plurality of oxetanyl groups in the molecule, that is, a polyfunctional oxetane compound, a compound having a plurality of thioether groups in the molecule, .

Examples of the polyfunctional epoxy compounds include bisphenol A epoxy resins, brominated epoxy resins, novolak epoxy resins, bisphenol F epoxy resins, hydrogenated bisphenol A epoxy resins, etc., such as jER828 manufactured by Mitsubishi Chemical Corporation , Glycidylamine type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, biquileneol type or biphenol type epoxy resin or a mixture thereof, bisphenol S type epoxy resin, bisphenol A Novolak type epoxy resin, tetraphenylol ethane type epoxy resin, TEPIC manufactured by Nissan Chemical Industries, Ltd., tetraglycidylsilane ethyl resin, naphthalene group-containing epoxy resin Epoxy resin, epoxy resin having dicyclopentadiene skeleton, flexible tough epoxy resin, glycidyl methacrylate copolymer There can be copolymerized epoxy resin of an epoxy resin, cyclohexyl maleimide and glycidyl methacrylate, but is not limited thereto. These epoxy resins may be used alone or in combination of two or more. Among these, a bifunctional epoxy resin is preferable from the viewpoint of flexibility. In particular, biphenyl novolak type epoxy resins, biquilene type epoxy resins or mixtures thereof are preferable from the viewpoint of flame retardancy.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [ (3-methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [ (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, In addition to polyfunctional oxetanes such as oligomers or copolymers thereof, oxetane alcohol and novolac resins, poly (p-hydroxystyrene), cardo type bisphenols, calixarene, calix resorcinarene or silses And ether of a resin having a hydroxyl group such as quinoxane. Other examples include copolymers of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate.

Examples of the episulfide resin having a plurality of cyclic (thio) ether groups in the molecule include YL7000 (bisphenol A type episulfide resin) manufactured by Mitsubishi Chemical Corporation, YSLV- 120TE and the like. An episulfide resin in which an epoxy group oxygen atom of the novolak type epoxy resin is substituted with a sulfur atom can also be used by using the same synthesis method.

The blending amount of the thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is preferably in the range of 0.3 to 2.5 equivalents, more preferably 0.5 to 2.0 equivalents relative to 1 equivalent of the carboxyl group of the carboxyl group-containing resin (A) to be. By keeping the compounding amount of the thermosetting component having a plurality of cyclic (thio) ether groups in the molecule at 0.3 equivalents or more, it is possible to prevent the carboxyl groups from remaining in the cured coating and to obtain good heat resistance, alkali resistance, electrical insulation and the like. On the other hand, when the amount is less than 2.5 equivalents, a cyclic (thio) ether group having a low molecular weight is prevented from remaining in the dry film, and the strength and the like of the cured film can be satisfactorily secured.

In the composition of the present invention, when a thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is used, it is preferable to further contain a thermosetting catalyst. Examples of such a thermosetting catalyst include imidazole derivatives, hydrazine compounds, phosphorus compounds such as triphenylphosphine, and the like. Further, it is also possible to use at least one selected from the group consisting of guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, Azine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid An S-triazine derivative such as an adduct may be used, and a compound which also functions as an adhesion promoter is preferably used in combination with the above-mentioned thermosetting catalyst.

The blending amount of these thermosetting catalysts is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15.0 parts by mass based on 100 parts by mass of the thermosetting component in terms of solid content.

In the present invention, among the above, it is preferable that at least one resin having no aromatic ring is contained as the thermosetting component (B). Examples of the resin having no aromatic ring which can be used as the thermosetting component include an isocyanate compound and an epoxy compound. Among them, triglycidyl isocyanurate containing 50 wt% or more of triglycidyl isocyanurate having a structure in which an epoxy group is bonded to the S-triazine skeletal surface in the same direction (for example, TEPIC-H, TEPIC-S manufactured by Kagaku Kogyo Co., Ltd.) is particularly preferable. triglycidyl isocyanurate containing 50 wt% or more of triglycidyl isocyanurate of the? form is transparent until the step of patterning the solder resist film by photo-curing and then tends to become cloudy when thermally cured have. Therefore, when the composition of the present invention is made white, the whiteness of the solder resist film to be obtained can be further increased and high reflectance can be obtained, which is preferable.

[(C) Inorganic filler]

The alkali-developable photosensitive resin composition of the present invention contains (C) an inorganic filler. Examples of the inorganic filler (C) include calcium carbonate, magnesium carbonate, fly ash, dehydrated sludge, natural silica, synthetic silica, kaolin, clay, calcium oxide, magnesium oxide, titanium oxide, zinc oxide, barium sulfate, , Magnesium hydroxide, talc, mica, hydrotalcite, aluminum silicate, magnesium silicate, calcium silicate, calcined talc, wollastonite, potassium titanate, magnesium sulfate, calcium sulfate, magnesium phosphate, sepiolite, boron nitride, boric acid A magnetic material such as aluminum, silica balloon, glass flake, glass balloon, amorphous silica, crystalline silica, fused silica, spherical silica, steel slag, copper, iron, iron oxide, carbon black, Cement, glass powder, neuburgite, diatomaceous earth, antimony trioxide, magnesium oxysulfate, aluminum hydrate, hydrated gypsum, alum Can. These inorganic fillers may be used singly or in combination of two or more kinds.

In the present invention, it is preferable that the inorganic filler (C) contains at least one of silica, barium sulfate and titanium oxide. As the silica, fused silica is preferable. Further, by containing barium sulfate and titanium oxide, the cured product of the composition can be made white, and high reflectance can be obtained. The titanium oxide may be titanium oxide having any of rutile type, anatase type and rhamstellite type. Ram seudel light type titanium oxide, is obtained by a lithium desorption treatment by a chemical oxidation carried out on persons seudel light type Li _{0 .5} TiO _2. Rutile-type titanium oxide is preferable because it does not cause discoloration due to light irradiation.

The blending amount of such an inorganic filler is preferably in the range of 5 to 80 mass%, more preferably in the range of 10 (mass%) to 10 To 70% by mass.

[(D) Photopolymerization initiator]

The alkali-developable photosensitive resin composition of the present invention contains (D) a photopolymerization initiator. As the photopolymerization initiator (D), any known photopolymerization initiator may be used as the photopolymerization initiator or photo radical generator. In the present invention, the (D1) bisacylphosphine oxide photopolymerization initiator and (D2) hydroxyacetophenone photopolymerization It is necessary to contain an initiator.

(D1) Bisacylphosphine oxide photopolymerization initiators include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis - (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and (2,5,6-trimethylbenzoyl) -2,4,4-trimethylpentylphosphine oxide. Among them, bis- (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (IRGACURE 819, BASF Japan) is easy to obtain and practical.

The blending amount of the bisacylphosphine oxide photopolymerization initiator (D1) in terms of solid content is preferably 0.1 to 50 parts by mass with respect to 100 parts by mass of the resin (A) containing a carboxyl group. By blending the bis (acylphosphine oxide) photopolymerization initiator (D1) in this range, the photocurability on copper becomes satisfactory, the curability of the coating film is improved, the coating film properties such as chemical resistance are improved, and the curability of the core is also improved . More preferably, it is 1 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin.

(D2) As the hydroxyacetophenone-based photopolymerization initiator, 1-hydroxy-cyclohexyl phenyl ketone (Irgacure 184, manufactured by BASF Japan Ltd.), 1- [4- (2-hydroxyethoxy) -phenyl ] -2-hydroxy-2-methyl-1-propan-1-one (IRGACURE 2959, BASF Japan) (2-hydroxy-2-methyl-1-phenylpropan-1-one (BASF Japan Co., Irgacure 127) -1-one (DAROCUR 1173 manufactured by BASF Japan Co., Ltd.).

The amount of the hydroxyacetophenone-based photopolymerization initiator (D2) is preferably 0.1 to 50 parts by mass based on 100 parts by mass of the resin (A) containing a carboxyl group in terms of solid content. (D2) a hydroxyacetophenone-based photopolymerization initiator within the above range, it is possible to obtain sufficient photocurability on copper while improving solubility of the (D1) bisacylphosphine oxide photopolymerization initiator, and And the coating film properties such as chemical resistance can be improved and the deep curing property can be improved. More preferably, it is 1 to 40 parts by mass with respect to 100 parts by mass of the (A) carboxyl group-containing resin.

The mixing ratio of the bisacylphosphine oxide photopolymerization initiator (D1) to the hydroxyacetophenone photopolymerization initiator (D2) is preferably 1: 0.5 to 1: 5, more preferably 1: 1 to 1: 3 .

The composition of the present invention may contain, as the photopolymerization initiator (D), a known photopolymerization initiator other than the bisacylphosphine oxide (D1) and the hydroxyacetophenone-based photopolymerization initiator (D2). Examples of the monoacylphosphine oxide include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,6- 2,4,6-trimethylbenzoylphenylphosphinic acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, and the like can be used. Among them, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (DAROCURE TPO, manufactured by BASF Japan Co., Ltd.) is easily available and practical.

Other examples of the photopolymerization initiator include benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether and benzoin n-butyl ether; Benzoin alkyl ethers; Benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-bisdiethylaminobenzophenone; Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, N, N-dimethylaniline, N, N-diethylamino-1- (4- Acetophenones such as N-dimethylaminoacetophenone; Thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-di Thioxanthones such as isopropylthioxanthone; Anthraquinones such as anthraquinone, chloroanthraquinone, 2-methyl anthraquinone, 2-ethyl anthraquinone, 2-tert-butyl anthraquinone, 1-chloro anthraquinone, 2-amylanthraquinone and 2-aminoanthraquinone; Ketal such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Benzoic acid esters such as ethyl-4-dimethylaminobenzoate, 2- (dimethylamino) ethylbenzoate and p-dimethylbenzoic acid ethyl ester; (9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-2-yl) Oxime esters such as 3-yl] -, 1- (0-acetyl oxime); Bis (η ⁵ -2,4- cyclopentadiene-1-yl) -bis (2,6-difluoro -3- (1H- pyrrol-1-yl) phenyl) titanium, bis (cyclopentadienyl) Titanocenes such as bis [2,6-difluoro-3- (2- (1-phenyl-1-yl) ethyl) phenyl] titanium; Phenyl disulfide 2-nitrofluorene, butyloline, anisoo ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide, and the like. All the above photopolymerization initiators may be used alone or in combination of two or more.

The blending amount of the other photopolymerization initiator is, for example, 0.1 to 40 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin (A) in terms of solid content.

(diluent)

The photosensitive resin composition of the present invention may contain a diluent. The diluent used in the present invention is used for improving the workability by adjusting the viscosity of the composition and for increasing the cross-linking density or improving the adhesiveness. The diluent is preferably a reactive diluent such as a photocurable monomer, or an organic solvent Can be used.

Examples of the photocurable monomer include alkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate and cyclohexyl (meth) acrylate; Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; Mono or di (meth) acrylates of alkylene oxide derivatives such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol; Polyhydric alcohols such as hexanediol, trimethylol propane, pentaerythritol, ditrimethylol propane, dipentaerythritol, and trishydroxy ethylisocyanurate, or polyvalent (meth) acrylates of the ethylene oxide or propylene oxide adduct Ryu; (Meth) acrylates of ethylene oxide or propylene oxide adduct of phenols such as phenoxyethyl (meth) acrylate and polyethoxydi (meth) acrylate of bisphenol A; (Meth) acrylates of glycidyl ethers such as glycerin diglycidyl ether, trimethylol propane triglycidyl ether and triglycidyl isocyanurate; And melamine (meth) acrylate.

The blending ratio of the photocurable monomer is preferably 5 to 100 parts by mass, more preferably 5 to 70 parts by mass, based on 100 parts by mass of the carboxyl group-containing resin (A). In the range of the blending ratio, photo-curability is improved, pattern formation is facilitated, and the strength of the cured film can be improved.

Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; Aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; Methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether And the like; Esters such as 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 acetate and propylene carbonate; Aliphatic hydrocarbons such as octane and decane; And petroleum solvents such as petroleum ether, petroleum naphtha and solvent naphtha. These organic solvents may be used alone or in combination of two or more.

(Other optional components)

The composition of the present invention may contain known additives in the field of electronic materials. Examples of additives include thermosetting catalysts, thermal polymerization inhibitors, ultraviolet absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, antioxidants, antibacterial and antifungal agents, antifoaming agents, leveling agents, fillers other than the above, thickeners, A thixotropic property-imparting agent, a colorant, a photoinitiator, and a sensitizer.

The dry film of the present invention has a resin layer obtained by applying and drying the composition of the present invention on a carrier film (support). The dry film can be formed by diluting the composition of the present invention with the above organic solvent and adjusting the viscosity to an appropriate viscosity, and then coating the resulting film with a solvent such as a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater, Coated on the carrier film by a coater or the like to a uniform thickness. Thereafter, the applied composition is dried at a temperature of usually 50 to 130 DEG C for 1 to 30 minutes to form a resin layer. The thickness of the coating film is not particularly limited, but is generally appropriately selected in the range of 10 to 150 占 퐉, preferably 20 to 60 占 퐉 in film thickness after drying.

As the carrier film, a plastic film is used, and it is preferable to use a plastic film such as a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, and a polystyrene film. The thickness of the carrier film is not particularly limited, but is generally appropriately selected in the range of 10 to 150 mu m.

It is preferable to further laminate a peelable cover film on the surface of the film for the purpose of preventing the adhesion of dust to the surface of the film after the resin layer containing the composition of the present invention is formed on the carrier film. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper and the like can be used. The cover film may be one that is smaller than the adhesive force between the resin layer and the carrier film when the cover film is peeled off.

The composition of the present invention may be prepared by a method such as dip coating, flow coating, roll coating, bar coating, screen printing, A curtain coating method and the like. Thereafter, the organic solvent contained in the composition is volatilized and dried (dried) at a temperature of about 60 to 100 DEG C, whereby a tack free resin layer can be formed. Further, in the case of a dry film obtained by applying the above composition onto a carrier film and drying it and then winding it as a film, the composition layer of the present invention is bonded to a substrate so as to be in contact with the substrate by a laminator, A layer can be formed.

As the base material, there may be used a base material such as paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / nonwoven epoxy, glass cloth / paper epoxy, synthetic fiber epoxy, fluorine / polyethylene / poly (FR-4 and the like), other polyimide films, PET films, glass substrates, glass substrates, and the like, which are made of materials such as copper clad laminate for high frequency circuit using phenylene ether, polyphenylene oxide, cyanate ester, A ceramic substrate, a wafer plate, and the like.

The volatile drying performed after application of the composition of the present invention can be carried out by a hot-air circulating drying furnace, a hot plate, a convection oven or the like (a hot air circulating type drying furnace equipped with a heat source of air heating by steam, And a method of spraying onto a support from a nozzle) can be used.

The composition of the present invention can form a cured coating film having excellent properties such as heat resistance, chemical resistance, hygroscopicity, adhesion, electrical properties and the like by heating at a temperature of, for example, about 140 to 180 캜.

Further, the exposed portion (light-irradiated portion) is cured by exposing (irradiating) the resin layer obtained by applying the composition of the present invention and volatilizing and drying the solvent. Concretely, the photoresist is selectively exposed to an active energy beam through a photomask having a pattern formed thereon by a contact or noncontact method, or directly pattern-exposed by a laser direct exposure machine, and the unexposed portion is exposed to a dilute alkali aqueous solution , 0.3 to 3 wt% aqueous sodium carbonate solution) to form a resist pattern.

As an exposure device used for irradiation with the active energy ray, any device that irradiates ultraviolet rays in a range of 350 to 450 nm with a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, Devices (e.g., laser direct imaging devices that draw images directly with a laser by CAD data from a computer) can also be used. As a laser light source of a direct shot, either a gas laser or a solid laser is used when laser light having a maximum wavelength in the range of 350 to 410 nm is used. The exposure dose for image formation varies depending on the film thickness and the like, but may be generally within the range of 20 to 800 mJ / cm 2, preferably 20 to 600 mJ / cm 2.

Examples of the developing method include a dipping method, a shower method, a spraying method, and a brushing method. As the developing solution, an aqueous alkali solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, have.

The composition of the present invention is suitable for formation of a cured film such as a solder resist or an interlayer insulating layer of a printed wiring board or a flexible printed wiring board. Further, the composition of the present invention can be used as a light source such as a light emitting diode (LED) or an electroluminescence (EL) used as a light source in a backlight of a liquid crystal display such as a lighting device, a portable terminal, a personal computer, And is suitably used for a reflector reflecting reflected light.

Example

Hereinafter, the present invention will be described in more detail with reference to examples.

Each component was blended according to the formulation shown in the following table, premixed by a stirrer, dispersed by a three roll mill, and kneaded to prepare a composition. The amounts in the tables represent parts by mass.

≪ Synthesis Example 1 (Production of carboxyl group-containing resin) >

42 parts by mass of methacrylic acid, 43 parts by mass of methyl methacrylate, 35 parts by mass of styrene, 35 parts by mass of benzyl acrylate, and 100 parts by mass of carbitol acetate 100 were added to a four-necked flask equipped with a reflux condenser, a thermometer, , 0.5 part by mass of lauryl mercaptan and 4 parts by mass of azobisisobutyronitrile were added and heated at 75 DEG C for 5 hours under a nitrogen stream to proceed the polymerization reaction to obtain a copolymer solution (solid content concentration: 50% by mass) . Then, 0.05 parts by mass of hydroquinone, 23 parts by mass of glycidyl methacrylate and 2.0 parts by mass of dimethylbenzylamine were added, and an addition reaction was carried out at 80 ° C for 24 hours. Then, 35 parts by mass of carbitol acetate was added, (Solid content concentration: 50% by mass).

<Sensitivity>

The compositions of the respective Examples and Comparative Examples were applied to the entire surface by screen printing on a patterned copper foil substrate and dried at 80 DEG C for 30 minutes. A step tablet (21 steps) made by Kodak Co., Ltd. was placed on the coated film on the substrate, exposed at an exposure amount of 600 mJ / cm 2 and developed with a 1% Na ₂ CO ₃ aqueous solution at a spray pressure of 2 kg / cm 2 for 1 minute Were investigated.

<Tag>

The compositions of each of the examples and comparative examples were coated on the entire surface by screen printing on each of the patterned copper foil substrates, dried by a hot air circulation type drying furnace at 80 캜 for 30 minutes, and allowed to cool to room temperature. A PET film was pressed on this substrate, and then the state of film adhesion when the PET film was peeled off was evaluated. A: No resistance was observed at the time of peeling off the film, and no marks were left on the coating film. A: When the film was peeled off, a little resistance was felt. When the film was slightly stained, And a case where a mark was clearly formed on the coated film was evaluated as x.

&Lt; Reflectivity &

The composition of each of the examples and the comparative examples was applied to a FR-4 copper-clad laminate having a size of 100 mm x 150 mm and a thickness of 1.6 mm by a screen printing method using 100 mesh polyester (made of biaser) A pattern was printed on the front surface (entire surface of the substrate) using a plate. These were dried at 80 DEG C for 30 minutes by a hot air circulation type drying furnace. Further, using an exposure machine HMW-680GW (manufactured by Oak Seisakusho Co., Ltd.) for a printed circuit board, ultraviolet light exposure was performed at an integrated light quantity of 900 mJ / cm2 so as to leave a quadrangular negative pattern of 30 mm on one side. Thereafter, using a 1% aqueous solution of sodium carbonate at 30 DEG C as a developer, these were developed for 60 seconds by a developing device for a printed wiring board, and then thermally cured at 150 DEG C for 60 minutes by a hot air circulation type drying furnace, A test piece was prepared.

The obtained test piece was evaluated by a color chromaticity meter CR-400 (manufactured by Konica Minolta Sensing Co., Ltd.). The value of Y was 85 or more, and the case of 80 or more and less than 85 was evaluated as? In addition, since the reflectance can not be obtained for the color tone of red or green, evaluation was not performed.

<Pencil hardness>

For each of the test pieces, a pencil of B to 9H ground so that the end of the core was flattened was pressed at an angle of about 45 degrees to record the hardness of the pencil which did not cause peeling of the coating film.

&Lt; Soldering heat resistance &

The rosin-based flux-coated test piece was immersed three times for 30 seconds each in a solder bath set at 260 DEG C, and the flux was washed with denatured alcohol, and then evaluated for peeling of the resist layer by naked eye. A case where peeling was not observed was indicated by?, A case where a slight peeling occurred, and a case where a significant peeling occurred was evaluated as?.

<Domestic delivery Gold plating resistance>

A commercially available electroless nickel plating bath and an electroless gold plating bath were used to conduct plating under the conditions of nickel 0.5 탆 and gold 0.03 탆 and the presence or absence of peeling of the resist layer was evaluated by tape peeling. A case in which no peeling occurred and a case where peeling occurred were evaluated as &amp; cir &amp;

<Tone>

The color tone of the obtained test piece was visually evaluated.

The above evaluation results are shown in the following table.

* 1) The carboxyl group-containing resin having an aromatic ring obtained in Synthesis Example 1

* 2) Diluted to 44 mass% with DPM (dipropylene glycol monomethyl ether) (manufactured by Daicel Chemical Industries, Ltd.) (carboxyl group-containing resin having no aromatic ring)

* 3) THPA (tetrahydrophthalic anhydride) is added to 40% of the hydroxyl groups generated after all the acrylic acid is added to the glycidyl ether moiety of MMA (methyl methacrylate) / GMA (glycidyl methacrylate) (Carboxyl group-containing resin having no aromatic ring) (manufactured by Osaka Kikin Kagaku Kogyo K.K.) diluted to 60% by mass with a resin (CA (carbitol acetate)),

* 4) (made by Nissan Chemical Industries, Ltd.) (resin having no aromatic ring)

* 5) Bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation (resin having an aromatic ring)

※ 6) Ishihara Sangyo Co., Ltd.

※ 7) Manufactured by Sakai Chemical Industry Co., Ltd.

※ 8) Aerosil # made by Nippon Aerosil Co., Ltd. # R974

* 9) Bisacylphosphine oxide photopolymerization initiator, Irgacure 819 (bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide), BASF Japan Co.,

* 10) Hydroxyacetophenone photopolymerization initiator, Irgacure 184, manufactured by BASF Japan Co., Ltd.

※ 11) Hydroxyacetophenone photopolymerization initiator, DARACURE 1173, BASF Japan Co., Ltd.

* 12) Monoacylphosphine oxide photopolymerization initiator, lucylline TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), BASF Japan Co.,

※ 13) Pigment Blue 15: 3

※ 14) Pigment Yellow 147

※ 15) Pigment Red 264

* 16) Imidazole compound, manufactured by Shikoku Kasei Kogyo Co., Ltd.

※ 17) Diethylene glycol monomethyl ether acetate

※ 18) Aromatic hydrocarbons (Solvesso 150)

* 19) Dipentaerythritol hexaacrylate, manufactured by Kyoeisha Chemical Co., Ltd.

※ 20) Coating could not be formed and evaluation could not be made.

From the results in the above table, it was confirmed that the compositions of the respective Examples are excellent in photo-curability and satisfy the performance as a solder resist.

Claims (7)

(A) a resin containing a carboxyl group, (B) a thermosetting component, (C) an inorganic filler and (D) a photopolymerization initiator,
Wherein the photopolymerization initiator (D) comprises a bisacylphosphine oxide photopolymerization initiator (D1) and a hydroxyacetophenone photopolymerization initiator (D2). The photosensitive resin composition according to claim 1, wherein the thermosetting component (B) contains at least one resin having no aromatic ring. The photosensitive resin composition according to claim 1 or 2, wherein the inorganic filler (C) contains titanium oxide. The photosensitive resin composition according to claim 1 or 2, wherein the bis (acylphosphine oxide) photopolymerization initiator (D1) is bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide. A dry film comprising a resin film obtained by applying and drying the photosensitive resin composition according to claim 1 or 2 on a carrier film. A photosensitive resin composition according to any one of claims 1 to 3, or a resin film obtained by applying and drying the photosensitive resin composition on a carrier film and curing a resin layer of a dry film having a resin layer by light irradiation freight. A printed wiring board having the cured product according to claim 6.