TWI874563B - Curable resin composition, dry film, cured product and electronic component - Google Patents

Abstract

The present invention provides a photosensitive curable resin composition capable of forming a cured product having excellent resolution and excellent chemical resistance, a dry film having a resin layer obtained from the composition, the cured product or a cured product of the resin layer of the dry film, and an electronic component having the cured product. The curable resin composition contains: (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a silica. The curable resin composition is characterized in that the silica (D) does not contain silica having a particle size exceeding 300 nm, and the ratio of the epoxy group of the epoxy resin (C) to the carboxyl group of the carboxyl group of the resin (A) containing a carboxyl group is 1.9 to 2.9.

Description

Curable resin composition, dry film, cured product and electronic component

The present invention relates to a curable resin composition, a dry film, a cured product and an electronic component.

Conventionally, as a multi-layer printed wiring board, there is known a structure in which a plurality of circuit boards having circuits formed thereon are laminated together with prepreg layers as interlayer insulating materials, and the circuits of each layer are connected by through holes. Also known is a build-up printed wiring board in which interlayer insulating materials and conductive layers are alternately stacked on the conductive layers of the inner circuit board (for example, refer to patent documents 1 and 2).

As such interlayer insulating materials, thermosetting interlayer insulating films are generally used, and the perforation openings for interlayer connection are formed by laser processing such as _CO2 laser. However, if laser processing is used, it is impossible to form a large number of perforation openings at one time, so a photosensitive interlayer insulating material that can use photolithography technology is sought.

On the other hand, wafer-level packaging is known as one of the packaging forms of semiconductor parts. When manufacturing this wafer-level packaging, in order to form a fine insulating pattern at one time, the demand for alkali-developable photosensitive insulating materials is high. [Prior art literature] [Patent literature]

[Patent Document 1] Japanese Patent Application Publication No. 2006-182991 (Patent Application Scope, etc.) [Patent Document 2] Japanese Patent Application Publication No. 2013-36042 (Patent Application Scope, etc.)

[Problems to be solved by the invention]

As mentioned above, in electronic parts, there is a demand for higher wiring density, and improving the resolution of photosensitive insulating materials has become a problem. The inventors of the present invention have focused on improving the resolution by mixing silica with a small maximum particle size as an inorganic filler. However, it is known that the cured film containing silica with such a small particle size has poor resistance to chemicals such as acetone and may crack.

Therefore, the purpose of the present invention is to provide a photosensitive curable resin composition that can form a cured product with excellent resolution and excellent chemical resistance, a dry film having a resin layer obtained from the composition, the cured product or a cured product of the resin layer of the dry film, and an electronic component having the cured product. [Means for solving the problem]

As a result of the inventors' active research to achieve the above-mentioned purpose, they found that the above-mentioned problem can be solved by mixing silica with a smaller maximum particle size and by setting the ratio of the carboxyl group of the carboxyl group-containing resin to the epoxy group of the epoxy resin contained in the composition to a specific range, thereby completing the present invention.

That is, the curable resin composition of the present invention comprises: (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin and (D) a silica. The curable resin composition is characterized in that the silica (D) does not contain silica particles with a diameter exceeding 300 nm, and the ratio of the epoxy group of the epoxy resin (C) to the carboxyl group of the carboxyl group of the resin (A) containing a carboxyl group is 1.9 to 2.9.

In the curable resin composition of the present invention, the content of the silicon dioxide (D) is preferably 5-35% by mass based on the total solid content of the composition.

In the curable resin composition of the present invention, the epoxy resin (C) contains only epoxy resins having an epoxy equivalent of 100 to 250 g/eq.

The dry film of the present invention is characterized by having a resin layer, which is obtained by coating the aforementioned hardening resin composition on a film and drying it.

The hardened material of the present invention is characterized by being obtained by hardening the aforementioned hardening resin composition or the resin layer of the aforementioned dry film.

The electronic component of the present invention is characterized by having the aforementioned hardened material. [Effect of the invention]

According to the present invention, a photosensitive curable resin composition capable of forming a cured product having excellent resolution and excellent chemical resistance, a dry film having a resin layer obtained from the composition, the cured product or a cured product of the resin layer of the dry film, and an electronic component having the cured product can be provided.

The curable resin composition of the present invention comprises: (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin and (D) silicon dioxide. The curable resin composition is characterized in that the silicon dioxide (D) does not contain silicon dioxide with a particle size exceeding 300 nm, and the ratio of epoxy groups of the epoxy resin (C) to carboxyl groups of the carboxyl group-containing resin (A) is 1.9-2.9.

In the present invention, it is important that the silica (D) does not contain silica having a particle size exceeding 300 nm. For example, as shown in Comparative Example 1 described below, silica having a particle size smaller than this can also improve resolution, but in this case, even if the above-mentioned epoxy group/carboxyl group ratio is set, the effect of improving drug resistance cannot be obtained.

In the present invention, "does not contain silicon dioxide with a particle size exceeding 300 nm", "particle size" refers not only to the particle size of primary particles but also to the particle size of secondary particles (agglomerates), and is a value measured by a dynamic light scattering method. An example of a dynamic light scattering measurement device is NanotracWave II UT151 manufactured by Microtrac Bell.

In the present invention, the ratio of epoxy groups of (C) epoxy resin/carboxyl groups of (A) carboxyl group-containing resin is the ratio of the number of epoxy groups of (C) epoxy resin to the number of carboxyl groups of (A) carboxyl group-containing resin contained in the composition. The ratio of epoxy groups of (C) epoxy resin/carboxyl groups of (A) carboxyl group-containing resin is preferably 1.9 to 2.6.

(C) The epoxy resin preferably contains only an epoxy resin having an epoxy equivalent of 100 to 250 g/eq., so that the resolution and chemical resistance are more excellent.

The following is a description of the components of the curable resin composition of the present invention.

[(A) Carboxyl-containing resin] As (A) carboxyl-containing resin, various carboxyl-containing resins known in the art having carboxyl groups in the molecule can be used. In particular, carboxyl-containing photosensitive resins having ethylenically unsaturated groups in the molecule are preferred in terms of photocurability and development resistance. The ethylenically unsaturated group is preferably derived from acrylic acid or methacrylic acid or a derivative thereof. When only a carboxyl-containing resin without ethylenically unsaturated groups is used, in order to make the composition photocurable, a compound having multiple ethylenically unsaturated groups in the molecule, i.e., a photoreactive monomer, must be used in combination.

Specific examples of carboxyl-containing resins include the following compounds (either oligomers or polymers). In this specification, the term "(meth)acrylate" is a general term for acrylate, methacrylate, and a mixture thereof, and the same applies to other similar expressions.

(1) Carboxyl-containing resins obtained by copolymerizing unsaturated carboxylic acids such as (meth)acrylic acid with unsaturated group-containing compounds such as styrene, α-methylstyrene, lower alkyl (meth)acrylates, isobutylene, etc.

(2) Carboxyl-containing urethane resins obtained by the polyaddition reaction of diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and diol compounds containing carboxyl groups such as dihydroxymethylpropionic acid and dihydroxymethylbutyric acid, and diol compounds such as polycarbonate polyols, polyether polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A-based epoxy alkyl adduct diols, and compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups.

(3) Urethane resins containing terminal carboxyl groups obtained by reacting the ends of urethane resins obtained by polyaddition reaction of diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, and diol compounds such as polycarbonate polyols, polyether polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A-based epoxide adduct diols, and compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups with acid anhydrides.

(4) A carboxyl-containing urethane resin obtained by subjecting a diisocyanate to a (meth)acrylate or a partially anhydride-modified product thereof of a bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, dimethylphenol type epoxy resin, or biphenol type epoxy resin, a carboxyl-containing diol compound, and a polyaddition reaction of a diol compound.

(5) In the synthesis of the resin of (2) or (4) above, a compound having one hydroxyl group and one or more (meth)acryl groups in the molecule, such as (meth)acrylate hydroxyalkyl ester, is added to prepare a carboxyl-containing urethane resin which is terminally (meth)acrylated.

(6) In the synthesis of the resin of (2) or (4) above, a compound having one isocyanate group and one or more (meth)acryl groups in the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, is added to prepare a carboxyl-containing urethane resin which is terminally (meth)acrylated.

(7) A multifunctional epoxy resin is reacted with (meth) acrylic acid to add a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. to the hydroxyl groups on the side chains to produce a carboxyl-containing resin.

(8) The hydroxyl group of the bifunctional epoxy resin is further epoxidized with epichlorohydrin to produce a polyfunctional epoxy resin which reacts with (meth)acrylic acid, and a dibasic acid anhydride is added to the produced hydroxyl group to produce a carboxyl-containing resin.

(9) A carboxyl-containing polyester resin is prepared by reacting a bifunctional cyclohexane resin with a dicarboxylic acid and adding a dibasic acid anhydride to the generated primary hydroxyl group.

(10) A carboxyl-containing resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide, and reacting the resulting reaction product with a monocarboxylic acid containing an unsaturated group, and reacting the resulting reaction product with a polyacid anhydride.

(11) A carboxyl-containing resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethyl carbonate or propylene carbonate, the resulting reaction product with a monocarboxylic acid containing an unsaturated group, and reacting the resulting reaction product with a polyacid anhydride.

(12) A carboxyl-containing resin obtained by reacting an epoxy compound having a plurality of epoxy groups in one molecule with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenylethanol with an unsaturated monocarboxylic acid such as (meth)acrylic acid, with a polyacid anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid, etc.

(13) A carboxyl group-containing resin having at least one of an amide structure and an imide structure.

(14) A carboxyl-containing resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in one molecule such as (meth)acrylate glycidyl (meth)acrylate, α-methylglycidyl (meth)acrylate, or 3,4-epoxycyclohexylmethyl methacrylate to the carboxyl-containing resin described in (1) to (13) above.

The above carboxyl group-containing resin preferably contains at least one of the carboxyl group-containing resins described in (7), (8), (10), (11), and (14). From the viewpoint of further improving the insulation reliability, it is preferred to contain the carboxyl group-containing resins described in (10) and (11).

(A) The carboxyl group-containing resin may be used alone or in combination of two or more.

The acid value of the (A) carboxyl-containing resin is preferably in the range of 20 to 120 mgKOH/g, and more preferably in the range of 30 to 100 mgKOH/g. By setting the acid value of the (A) carboxyl-containing resin to the above range, alkaline development can be performed well and a normal cured pattern can be formed. The weight average molecular weight of the (A) carboxyl-containing resin varies depending on the resin skeleton, but is generally preferably 2,000 to 150,000. When the weight average molecular weight is 2,000 or more, the dry coating has good non-tackiness, moisture resistance of the coating after exposure, and resolution. On the other hand, when the weight average molecular weight is 150,000 or less, the developing property and storage stability are good. More preferably, it is 5,000 to 100,000.

[(B) Photopolymerization initiator] As the (B) photopolymerization initiator, any photopolymerization initiator known as a photopolymerization initiator or a photoradical generator may be used. Examples thereof include bis-(2,6-dichlorobenzyl)phenylphosphine oxide, bis-(2,6-dichlorobenzyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzyl)phenylphosphine oxide, bis-(2 ,6-dimethoxybenzyl)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzyl)-phenylphosphine oxide, etc.; 2,6-dimethoxybenzyldiphenylphosphine oxide, 2,6-dichlorobenzyldiphenylphosphine oxide, 2 , methyl 4,6-trimethylbenzylphenylphosphonate, 2-methylbenzyldiphenylphosphine oxide, isopropyl tert-pentylphenylphosphonate, 2,4,6-trimethylbenzyldiphenylphosphine oxide, etc.; monoacylphosphine oxides; 1-hydroxy-cyclohexylphenyl ketone, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy -1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propane-1-one, 2-hydroxy-2-methyl-1-phenylpropane-1-one and other hydroxyacetophenones; benzoin, biphenyl acyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether and other benzoin alkyl ethers; diphenyl Benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, etc.; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-(methyl) Acetophenones such as 2-(4-(4-phenyl)thio)phenyl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholino)phenyl]-1-butanone, N,N-dimethylaminoacetophenone, etc.; thiothione, 2-ethylthiothione, 2-isopropylthiothione Thionones such as anthraquinone, 2,4-dimethylthiazonone, 2,4-diethylthiazonone, 2-chlorothiazonone, 2,4-diisopropylthiazonone, etc.; anthraquinones such as anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone, etc.; acetals such as acetophenone dimethyl acetal, benzyl dimethyl acetal, etc.; Benzoate esters such as ethyl-dimethylaminobenzoate, 2-(dimethylamino)ethyl benzoate, ethyl-p-dimethylbenzoate, etc.; oxime esters such as 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyl oxime)], ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-, 1-(O-acetyl oxime), etc.; bis(η ⁽ B) The photopolymerization initiator preferably contains an acylphosphine-based photopolymerization initiator such as a bisacylphosphine oxide or a monoacylphosphine oxide in order to improve the exposure sensitivity. (B) The photopolymerization initiator may be used alone or in combination of two or more.

The amount of the photopolymerization initiator (B) is preferably 0.5 to 20 parts by weight relative to 100 parts by weight of the carboxyl group-containing resin (A). When the amount is 0.5 parts by weight or more, the surface curing property becomes good, and when the amount is 20 parts by weight or less, halo is not easily generated, and good resolution is obtained.

[(C) Epoxy resin] As the (C) epoxy resin, any conventional epoxy resin can be used, preferably a multifunctional epoxy resin having two or more epoxy groups. The epoxy resin can be liquid, solid or even semi-solid. Examples of the multifunctional epoxy resin include bisphenol A type epoxy resin; brominated epoxy resin; novolac type epoxy resin; bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidylamine type epoxy resin; hydantoin type epoxy resin; alicyclic epoxy resin; trihydroxyphenylmethane type epoxy resin; dimethylphenol type or diphenol type epoxy resin or a mixture thereof; bisphenol S type epoxy resin; bisphenol A novolac type epoxy resin; tetrahydroxybenzene ethylene type epoxy resin; heterocyclic epoxy resin; diglycidyl phthalate resin; tetraglycidyl dimethylbenzene ethyl resin; naphthyl-containing epoxy resin; dicyclopentadiene type epoxy resin; methacrylate glycidyl ester copolymer epoxy resin; cyclohexylmaleimide and methacrylate glycidyl ester copolymer epoxy resin; epoxy-modified polybutadiene rubber derivative; CTBN-modified epoxy resin, etc., but not limited to these. (C) The epoxy resin may be used alone or in combination of two or more. The epoxy resin (C) is preferably a bisphenol A type or bisphenol F type novolac type epoxy resin, a biphenylene type epoxy resin, a biphenol type epoxy resin, a biphenol novolac type (biphenylaralkyl type) epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin or a mixture thereof.

(C) The epoxy equivalent of the epoxy resin is preferably 100 to 300 g/eq., more preferably 100 to 250 g/eq.

[(D) Silica] The curable resin composition of the present invention contains (D) silica as a filler component, but does not contain silica with a particle size exceeding 300 nm. By containing silica, a cured product with a small linear expansion coefficient can be obtained. Examples of silica include fused silica, spherical silica, amorphous silica, crystalline silica, etc., among which spherical silica is preferred. The method for producing (D) silica is not particularly limited, but the sol-gel method is preferred based on obtaining silica with a small maximum particle size.

The maximum particle size of the (D) silicon dioxide is 300 nm or less, preferably 280 nm or less, and the average particle size (D50, median diameter) of the (D) silicon dioxide is preferably 120 nm or less, more preferably 60 nm or less, and even more preferably 30 nm or less.

(D) Silica is preferably surface treated Silica. Surface treatment here refers to treatment to improve compatibility with resin components. The surface of Silica may also be subjected to surface treatment to introduce curable reactive groups. Here, the so-called curable reactive groups are not particularly limited if they are groups that undergo curing reaction with curable compounds such as (A) carboxyl-containing resins or (C) epoxy resins, and may be photocurable reactive groups or thermocurable reactive groups. Examples of photocurable reactive groups include methacrylic acid, acrylic acid, vinyl, styrene, etc., and examples of thermocurable reactive groups include epoxy, amino, hydroxyl, carboxyl, isocyanate, imino, cyclobutyl, oxadiazole, methoxymethyl, methoxyethyl, ethoxymethyl, ethoxyethyl, oxazoline, etc. The method of introducing the curable reactive group into the surface of silica is not particularly limited, and the method can be introduced by a conventional method, and the surface of silica can be treated with a surface treatment agent having a curable reactive group, such as a coupling agent having a curable reactive group as an organic group. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, etc. can be used. Examples of surface-treated silica having no curable reactive group include silica-alumina surface-treated silica, silica treated with a titanium ester coupling agent, silica treated with an aluminate coupling agent, and silica treated with an organic agent.

The method for adjusting the average particle size of (D) silicon dioxide is not particularly limited, and it is preferably dispersed in advance using a bead mill or a jet mill. Also, as (D) silicon dioxide, a commercially available product having a maximum particle size and an average particle size within the above range may be used directly. Examples of commercially available products include QSG-10 (average particle size 15 nm, maximum particle size 40 nm), QSG-30 (average particle size 30 nm, maximum particle size 70 nm), and QSG-100 (average particle size 110 nm, maximum particle size 270 nm) manufactured by Shin-Etsu Chemical Co., Ltd., PGM-AC-2140Y (silica dispersed in propylene glycol monomethyl ether, solid content concentration 42% by mass, average particle size 12 nm, maximum particle size 30 nm) manufactured by Nissan Chemical Co., Ltd., and MEK-EC-2130Y (silica dispersed in methyl ethyl ketone, solid content concentration 30% by mass). , average particle size 12nm, maximum particle size 30nm), MEK-EC2430Z (silica dispersed in methyl ethyl ketone, solid concentration 30% by mass, average particle size 12nm, maximum particle size 30nm), PMA-ST (silica dispersed in propylene glycol monomethyl ether, solid concentration 30% by mass, average particle size 12nm, maximum particle size 30nm), ADOMATECHS YA050C-LHQ (silica dispersed in propylene glycol monomethyl ether acetate, solid concentration 40% by mass, average particle size 50nm, maximum particle size 180nm), etc.

(D) Silica can also be prepared in a slurry state. By preparing in a slurry state, it is easy to highly disperse, prevent aggregation, and it is easy to handle silica with a maximum particle size within the above-mentioned specific range.

(D) Silica may be used alone or in combination of two or more. The amount of (D) Silica is preferably 5 to 35% by weight, more preferably 10 to 30% by weight, based on the total solid content of the composition. If the amount of (D) Silica is within the above range, the resolution is better.

(Compounds having ethylenically unsaturated groups) The curable resin composition of the present invention may also contain compounds having ethylenically unsaturated groups. Compounds having ethylenically unsaturated groups are photocured by irradiation with active energy rays, and the irradiated portion of the resin layer is made insoluble or assisted to be insoluble in an alkaline aqueous solution. As compounds having ethylenically unsaturated groups, photopolymerizable oligomers of known and conventional photosensitive monomers, photopolymerizable vinyl monomers, etc. can be used. As compounds having ethylenically unsaturated groups, photosensitive (meth)acrylate compounds can be used. Compounds having ethylenically unsaturated groups can be used alone or in combination of two or more. In addition, in this specification, compounds having ethylenically unsaturated groups do not include carboxyl-containing resins having ethylenically unsaturated groups.

Examples of compounds having ethylenically unsaturated groups include commonly used polyester (meth)acrylates, polyether (meth)acrylates, urethane (meth)acrylates, carbonate (meth)acrylates, epoxy (meth)acrylates, urethane (meth)acrylates, specifically hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; ethylene glycol, methyl methacrylate ... Diacrylates of glycols such as oxytetraethylene glycol, polyethylene glycol, and propylene glycol; acrylamides such as N,N-dimethylacrylamide, N-hydroxymethylacrylamide, and N,N-dimethylaminopropylacrylamide; acrylate aminoalkyl esters such as N,N-dimethylaminoethyl acrylate and N,N-dimethylaminopropyl acrylate; hexanediol, trihydroxymethylpropane, pentaerythritol, dipentaerythritol, tris(2-hydroxy-2-methylpropane), dimethoxy-2-methylpropane, ... - Polyols of hydroxyethyl isocyanurate or their ethylene oxide adducts, propylene oxide adducts, or ε-caprolactone adducts, etc., polyacrylates; phenoxy acrylate, bisphenol A diacrylate, and phenols of the ethylene oxide adducts or propylene oxide adducts, etc., polyacrylates; glycerol diglycidyl ether, glycerol triglycidyl ether, trihydroxymethylpropane triglycidyl ether, triglycerol ... Polyacrylates of glycidyl ethers of hydroglyceryl isocyanurate, etc.; not limited to the above, examples include polyether polyols, polycarbonate diols, hydroxyl-terminated polybutadiene, polyester polyols and other polyols directly acrylated, or acrylates acrylated by urethane acrylate via diisocyanate, and melamine acrylates, and at least one of the methacrylates corresponding to the above acrylates.

Furthermore, epoxy acrylate resins obtained by reacting a multifunctional epoxy resin such as a cresol novolac epoxy resin with acrylic acid, or epoxy urethane acrylate compounds obtained by reacting a hydroxyl group of the epoxy acrylate resin with a hydroxyl acrylate such as pentaerythritol triacrylate and a diisocyanate such as isophorone diisocyanate to form a semi-urethane compound. Such epoxy acrylate resins can improve the photocurability without reducing the touch drying property.

The amount of the compound having an ethylenically unsaturated group is preferably 1 to 60 parts by mass, more preferably 5 to 55 parts by mass, and even more preferably 10 to 50 parts by mass per 100 parts by mass of the carboxyl group-containing resin (A). By making the amount within the above range, good light reactivity and heat resistance can be obtained.

(Thermosetting accelerator) The curable resin composition of the present invention may contain a thermosetting accelerator. The thermosetting accelerator may be used alone or in combination of two or more.

Examples of the heat curing accelerator include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; amine compounds such as dicyanodiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, and 4-methyl-N,N-dimethylbenzylamine; hydrazide compounds such as dihydrazide of adipic acid and dihydrazide of sebacic acid; and phosphorus compounds such as triphenylphosphine. In addition to the above, S-triazine derivatives such as guanidine, acetylguanidine, benzoguanidine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine.isocyanuric acid adduct, and 2,4-diamino-6-methacryloyloxyethyl-S-triazine.isocyanuric acid adduct can also be used.

Examples of commercially available heat-curing accelerators include 2MZ-A, 2MZ-OK, 2PHZ, 1B2PZ, 2P4BHZ, and 2P4MHZ (all trade names of imidazole compounds) manufactured by Shikoku Chemical Industries, Ltd., U-CAT3503N and U-CAT3502T (all trade names of dimethylamino-blocked isocyanate compounds), and DBU, DBN, U-CATSA102 and U-CAT5002 (all bicyclic amidine compounds and their salts) manufactured by SAN APRO.

The amount of the heat curing accelerator to be added is preferably 0.1 to 10 parts by weight, more preferably 0.1 to 5.0 parts by weight, per 100 parts by weight of the carboxyl group-containing resin (A). When the amount is 0.1 parts by weight or more, the heat resistance of the cured product is good, and when the amount is 10 parts by weight or less, the storage stability is good.

(Organic solvent) The curable resin composition of the present invention may use an organic solvent to prepare the resin composition or to adjust the viscosity of the resin composition for coating on a substrate or carrier film. Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum-based solvents, etc. More specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellulose, methyl cellulose, butyl cellulose, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, ethylene glycol, and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. The organic solvent may be used alone or in combination of two or more.

(Other optional ingredients) Other additives commonly used in the field of electronic materials may also be formulated in the curable resin composition of the present invention. Examples of other additives include thermal polymerization inhibitors, ultraviolet absorbers, coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial/anti-mold agents, defoaming agents, leveling agents, thickeners, adhesion agents, thixotropic agents, colorants, photoinitiators, sensitizers, curing agents, thermoplastic resins, organic fillers, mold release agents, surface treatment agents, dispersants, dispersing aids, surface modifiers, stabilizers, and fluorescent materials.

The curable resin composition of the present invention is suitable for forming an insulating curing film for a printed wiring board, more suitable for forming an insulating permanent film, and more suitable for forming a cover layer, a solder resist, and an interlayer insulating material, and is particularly suitable for forming an interlayer insulating material. Moreover, it is suitable for forming a permanent film (especially an interlayer insulating material) for printed wiring boards that require high reliability, such as packaging substrates, especially FC-BGA. In addition, the curable resin composition of the present invention can also be used to form solder dams, etc. As electronic components, it can also be used for purposes other than printed wiring boards, such as passive parts such as inductors. The curable resin composition of the present invention may be a liquid type or a dry film type obtained by drying the liquid type resin composition. The liquid type resin composition may be a two-component type or the like from the viewpoint of storage stability, but may also be a one-component type.

[Dry film] The dry film of the present invention is a resin layer obtained by coating the curable resin composition of the present invention on a film (hereinafter also referred to as a "carrier film") and then drying it. The dry film of the present invention can be diluted with an organic solvent to adjust the curable resin composition of the present invention to a suitable viscosity, and then applied to a carrier film with a uniform thickness by a notch wheel coater, a scraper coater, a lip die coater, a rod coater, a rubber roller coater, a reverse roller coater, a conveyor roller coater, a gravure coater, a spray coater, etc., and is usually obtained by drying at a temperature of 50 to 120°C for 1 to 30 minutes. There is no particular restriction on the thickness of the coated film, but the film thickness after drying is generally set appropriately in the range of 5 to 150 μm, preferably 10 to 60 μm. The film is not limited to a carrier film and may be a cover film.

As the carrier film, a plastic film can be preferably used, and preferably a polyester film such as polyethylene terephthalate, a polyimide film, a polyamide-imide film, a polypropylene film, a polystyrene film, etc. The thickness of the carrier film is not particularly limited, but is generally appropriately selected within the range of 10 to 150 μm.

After coating the curable resin composition of the present invention on the carrier film, a peelable cover film may be further laminated on the film surface for the purpose of preventing dust from adhering to the coating film surface. The peelable cover film may be, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, etc., as long as the adhesion between the film and the cover film is smaller than the adhesion between the film and the carrier film when the cover film is peeled off.

The volatilization drying of the curable resin composition of the present invention after being coated on the carrier film can be carried out using a hot air circulation drying furnace, an IR furnace, a heating plate, a forced oven, etc. (using a method of hot air convection contact in a drying machine with a heat source using air heating such as steam, and a method of blowing the support body with a nozzle).

[Hardened product] The cured product of the present invention is formed by hardening the curable resin composition of the present invention and the resin layer of the dry film of the present invention.

[Electronic components] The electronic components of the present invention are those having the cured product of the present invention. The electronic components of the present invention can be obtained by directly applying the curable resin composition of the present invention and by using the dry film of the present invention. The following will be described using the case of manufacturing a printed wiring board as an example of an electronic component, but the present invention is not limited thereto.

In the case of manufacturing a printed wiring board by a direct coating method, the curable resin composition of the present invention is directly coated on a printed wiring board forming a circuit, and after forming a coating film of the resin composition, the active energy line such as laser light is directly irradiated through the pattern, or the active energy line is selectively irradiated through a photomask formed with a pattern, and the unexposed part is developed with a dilute alkaline aqueous solution to form a pattern. Furthermore, by irradiating the formed pattern with active energy line at, for example, 100 to 2000 mJ/ ^cm2 , and curing it by heating at, for example, a temperature of about 140 to 200°C, a printed wiring board having a pattern of a cured product is manufactured. In addition, the irradiation of the pattern with active energy line is performed to make the light-curing components that have not reacted during exposure when forming the image almost completely cure.

When using a dry film, the dry film of the present invention is laminated to a printed wiring board for forming a circuit, and after exposure in the same manner as above, the carrier film is peeled off and developed. Subsequently, the resin layer is irradiated with active energy rays and heated and cured at a temperature of, for example, about 140 to 200°C to produce a printed wiring board having a pattern of the cured product.

As an exposure machine used for active energy ray irradiation, any device that can irradiate active energy ray in the range of 350~450nm equipped with a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halogen lamp, a mercury arc lamp, etc. can be used. Furthermore, a direct drawing device such as a direct imaging device that directly draws an image with active energy ray using CAD data from a computer can also be used. As a light source for the direct drawing device, if it is a mercury arc lamp, an LED, or a laser light with a maximum wavelength in the range of 350~450nm, it can be any of a gas laser and a solid laser. The exposure dose used for pattern formation varies with film thickness, but is generally in the range of 20 to 1500 mJ/cm ² , preferably 20 to 1200 mJ/cm ² .

As a developing method, an immersion method, a rinsing method, a spray method, a brushing method, etc. can be used, and as a developer, an alkaline aqueous solution of potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines, etc. can be used. [Example]

The present invention is described in more detail below using examples, but the present invention is not limited to the following examples. In addition, the following "parts" and "%" are all based on mass unless otherwise specified.

[Synthesis of carboxyl-containing resin] (Synthesis Example 1: Carboxyl-containing resin 1) In a high pressure autoclave equipped with a thermometer, a nitrogen and oxirane inlet device, and a stirring device, 119.4 parts by mass of a novolac type cresol resin (trade name "SHONOL CRG951", manufactured by AICA Industries, OH equivalent: 119.4), 1.19 parts by mass of potassium hydroxide, and 119.4 parts by mass of toluene were added, and the nitrogen was replaced in the system while stirring, and the temperature was raised. Next, 63.8 parts by mass of propylene oxide was slowly added dropwise, and the reaction was carried out at 125-132°C and 0-4.8 kg/cm ² for 16 hours. Then, the mixture was cooled to room temperature, and 1.56 parts by weight of 89% phosphoric acid was added to the reaction solution to neutralize potassium hydroxide, thereby obtaining a phenolic lacquer type cresol resin propylene oxide reaction solution with a solid content of 62.1% and a hydroxyl value of 182.2 mgKOH/g (307.9 g/eq.). This is a solution in which 1.08 mol of phenolic hydroxyl groups are added per 1 equivalent of propylene oxide. The obtained propylene oxide reaction solution of novolac type cresol resin (293.0 parts by mass), acrylic acid (43.2 parts by mass), methanesulfonic acid (11.53 parts by mass), methyl hydroquinone (0.18 parts by mass) and toluene (252.9 parts by mass) were fed into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and the air was blown in at a rate of 10 ml/min. The mixture was stirred and reacted at 110°C for 12 hours. The water generated by the reaction was an azeotropic mixture with toluene, and 12.6 parts by mass of water was distilled out. The mixture was then cooled to room temperature, and the obtained reaction solution was neutralized with 35.35 parts by mass of a 15% sodium hydroxide aqueous solution, and then washed with water. Subsequently, 118.1 parts by mass of diethylene glycol monoethyl ether acetate was used to replace toluene in an evaporator and distilled off to obtain a novolac type acrylate resin solution. Next, 332.5 parts by mass of the obtained novolac type acrylate resin solution and 1.22 parts by mass of triphenylphosphine were fed into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was blown in at a rate of 10 ml/min. While stirring, 60.8 parts by mass of tetrahydrophthalic anhydride was slowly added, and the reaction was carried out at 95-101°C for 6 hours, and the reaction was taken out after cooling. In this way, a solution of a photosensitive carboxyl-containing resin 1 with a solid content of 70.6% and a solid acid value of 87.7 mgKOH/g was obtained.

(Synthesis Example 2: Carboxyl-containing resin 2) Add 1070 parts of o-cresol novolac epoxy resin (EPICLONN-695 manufactured by DIC Corporation, softening point 95°C, epoxy equivalent 214, average functional group number 7.6) (5.0 mol of glycidyl groups (total number of aromatic rings)), 360 parts of acrylic acid (5.0 mol) and 1.5 parts of hydroquinone to 650 parts of diethylene glycol monomethyl ether acetate, heat and stir at 100°C to dissolve uniformly. Next, add 4.3 parts of triphenylphosphine, heat and react at 110°C for 2 hours, then add 1.6 parts of triphenylphosphine, raise the temperature to 120°C and react for 12 hours. 525 parts of aromatic hydrocarbon (SOLVESSO 150) and 608 parts (4.0 mol) of tetrahydrophthalic anhydride were added to the obtained reaction solution, and the mixture was reacted at 110° C. for 4 hours. 142.0 parts (1.0 mol) of glycidyl methacrylate was further added to the obtained reaction solution, and the mixture was reacted at 115° C. for 4 hours to obtain a solution of photosensitive carboxyl-containing resin 2 having a solid acid value of 77 mgKOH/g and a solid content of 65%.

[Examples 1 to 9, Comparative Examples 1 to 5] The various components shown in Table 1 below were mixed in the proportions (mass parts) shown in the table, pre-mixed with a stirrer, and then kneaded with a bead mill to prepare a curable resin composition. In addition, the mixing amount of each component recorded in the table is the mass part of the solid content excluding the solvent. In addition, the stirring conditions of the stirrer are rotation speed 800 rpm, stirring time 10 minutes, stirring blade 12 cm, and as a bead mill, a cone type K-8 (manufactured by BUHLER) was used, and the conditions for kneading were zirconia beads, rotation speed 1000 rpm, spraying amount 20%, bead diameter 0.65 mm, and filling rate 88%. The hardening resin composition prepared above was coated on a 38 μm polyester film using a coating machine, and dried in a hot air circulation drying oven at 80° C. for 20 minutes to prepare a dry film having a resin layer with a thickness of 10 μm.

<Resolution Evaluation> A 17μm thick electrolytic copper-plated substrate was attached to a FR-4 1.6mm thick copper foil 18μm thick copper laminate, and etched with CZ-8101B made by MERCK. The dry film was laminated using a vacuum laminating machine (CVP-300: made by MIKKO MATERIAL) at 90°C in the first chamber under the conditions of vacuum pressure of 3hPa and vacuum time of 30 seconds, and then pressed under the conditions of pressing pressure of 0.5MPa and pressing time of 30 seconds. Then, the polyester film was peeled off and exposed with each opening pattern using an exposure device equipped with a high-pressure mercury lamp. The exposure was adjusted in a step tablet (Photec 41 segment) in a manner that the gloss sensitivity became 7 segments. Thereafter, the image was developed with a 1 mass% Na ₂ CO ₃ aqueous solution at 30°C at a spray pressure of 2kg/cm ² for 120 seconds. The substrate with the cured film was irradiated with ultraviolet rays in a UV conveyor furnace at a cumulative exposure of 1000mJ/cm ² , and then heat-cured at 180°C for 60 minutes. The opening diameter of the obtained cured product was observed by SEM, and the occurrence of halo and undercut was evaluated according to the following criteria. ◎: A good opening diameter was obtained with an opening diameter of 8μm. ○: A good opening diameter was obtained with an opening diameter of 10μm. △: A good opening diameter was obtained with an opening diameter of 15 μm. ×: A good opening diameter could not be obtained with an opening diameter of 15 μm.

<Evaluation of chemical resistance> In addition to setting the copper-plated substrate as the resin layer of the dry film on the 6-inch wafer, a substrate with a cured film was obtained in the same way as the above <Evaluation of resolution> test. The obtained substrate with a cured film was immersed in acetone for 30 minutes to check whether there was any cracking. ◎: No cracking occurred after acetone immersion. ○: Although discoloration was observed after acetone immersion, no cracking occurred. ×: Partial cracking occurred after acetone immersion. ××: The material was fully cracked after acetone immersion.

<Evaluation of thermal expansion coefficient (CTE)> The same test as the above <Evaluation of resolution> was performed except that the copper-plated substrate was replaced with GTS-MP foil (manufactured by Furukawa Circuit Foil Co., Ltd.) and a dry film resin layer was attached to the glossy side (copper foil) to expose the entire surface. The cured film was peeled off from the copper foil and cut into 3mm wide x 30mm long. The CTE of the test piece was measured using TMA (Thermomechanical Analysis) Q400 manufactured by DI INSTRUMENTS Co., Ltd. The measurement conditions are tensile mode, 16mm between the clamps, 50mN load, and in a nitrogen environment, the temperature is increased from 20℃ to 300℃ at 10℃/min, then the temperature is decreased from 300℃ to -40℃ at 10℃/min, and then the temperature is increased from -40℃ to 300℃ at 10℃/min. The thermal expansion coefficient (CTEα1) below Tg when the temperature is increased from -40℃ to 300℃ at 10℃/min is obtained. ◎: CTEα1 is less than 45ppm. ○: CTEα1 is 45ppm or more and less than 55ppm. △: CTEα1 is 55ppm or more and less than 65ppm. ×: CTEα1 is 65ppm or more.

<Insulation reliability (B-HAST resistance (L/S=10/10μm))> A substrate with a cured film was prepared in the same manner as the substrate for evaluation of resolution, except that the substrate was set to have a comb pattern of L/S=10/10μm and was fully exposed. Then, HAST was performed under the conditions of 130℃, 85%RH, 3.5V applied voltage, and in-bath measurement. The evaluation criteria are as follows. ○: No abnormality for more than 300 hours △: Short circuit at 200~300 hours. ×: Short circuit within 200 hours.

<Adhesion Evaluation> (Step 1) For a 1.6mm thick FR-4 copper laminate, after the copper is completely removed by etching with ferric chloride (hereinafter referred to as "etched-off board"), four sides of an 18μm thick electrolytic copper foil slightly smaller than the first etched-off board are fixed with chemical-resistant adhesive tape. This state is a state where the electrolytic copper foil is exposed outside the tape attachment area. Next, a copper foil-attached substrate is made using the electrolytic copper foil attached by ETCHBOND CZ-8101 chemical polishing made by MERCK. (Step 2) The resin layer of the prepared dry film was laminated on the copper foil surface of the copper foil substrate prepared in the above step 1 using a vacuum laminating press (CVP-300: manufactured by NIKKO MATERIAL Co., Ltd.) in the first chamber at 90°C with a vacuum pressure of 3 hPa and a vacuum time of 30 seconds, and then pressed at a pressure of 0.5 MPa and a pressing time of 30 seconds. Next, the obtained evaluation substrate was exposed at 400 mJ/ ^cm2 using an exposure device equipped with a high-pressure mercury lamp, the PET film was peeled off, and the image was developed for 120 seconds using a 1 mass% sodium carbonate aqueous solution at 30°C with a spray pressure of 0.2 MPa. After development, UV rays were irradiated with a cumulative exposure of 1000mJ/ ^cm2 in a UV conveyor furnace, and then heated at 180°C for 60 minutes to cure, thereby preparing a test piece with a cured film of each composition formed on the copper foil of the copper foil-attached substrate. (Step 3) The cured film surface of the test piece prepared in step 2 was bonded to the second etched plate with four sides slightly smaller than the copper foil of the test piece with a two-component epoxy adhesive (ARALDITE STANDARD), and cured at 60°C for 4 hours. The peel strength measurement sample of the copper foil chemically polished after the hardening film of each component is formed by cutting with a cutter to the size of the second etched plate after hardening, and the plate is separated from the first etched plate and turned over. (Measurement) The prepared peel strength measurement sample is cut into 1 cm wide and 7 cm long. The adhesion strength at an angle of 90 degrees is obtained using the small table tester EZ-SX manufactured by Shimadzu Corporation and the 90° PRINT HAKURI jig. The evaluation criteria are as follows. ○: The adhesion to the copper substrate is 5N/cm or more. △: The adhesion to the copper substrate is 3N/cm or more and less than 5N/cm. ×: The adhesion to the copper substrate is less than 3N/cm.

*1: Solution of carboxyl-containing resin 1 synthesized above (solid content 70.6%, solid acid value 87.7 mgKOH/g) *2: Solution of carboxyl-containing resin 2 synthesized above (solid content 65%, solid acid value 77 mgKOH/g) *3: Omnirad TPO H (manufactured by IGM Resin Co., Ltd.) *4: Dicyclopentadiene type epoxy resin HP-7200L (epoxy equivalent: 248 g/eq, manufactured by DIC Corporation) *5: Naphthalene type epoxy resin HP-4032D (epoxy equivalent: 136 g/eq, manufactured by DIC Corporation) *6: Biphenyl aralkyl type epoxy resin NC-3000H (epoxy equivalent: 286 g/eq, manufactured by Nippon Kayaku Co., Ltd.) *7: QSG-10 (average particle size 15 nm, maximum particle size 40 nm) Manufactured by Shin-Etsu Chemical Co., Ltd. *8: QSG-30 (average particle size 30nm, maximum particle size 70nm) Manufactured by Shin-Etsu Chemical Co., Ltd. *9: QSG-100 (average particle size 110nm, maximum particle size 270nm) Manufactured by Shin-Etsu Chemical Co., Ltd. *10: QSG-170 (average particle size 170nm, maximum particle size 420nm) Manufactured by Shin-Etsu Chemical Co., Ltd. *11: SO-C5 (average particle size 1100nm, maximum particle size 7000nm) Manufactured by ADOMATECHS Co., Ltd. *12: 1B2PZ (manufactured by Shikoku Chemical Co., Ltd.) *13: Dipentaerythritol hexaacrylate DPHA (manufactured by Nippon Kayaku Co., Ltd.) *14: Ratio of epoxy group of epoxy resin/carboxyl group of carboxyl group-containing resin

From the results shown in the above table, it can be seen that the hardening resin compositions of Examples 1 to 9 of the present invention have excellent resolution and chemical resistance.

Claims (4)

A curable resin composition comprising (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) silicon dioxide, wherein the silicon dioxide (D) does not contain silicon dioxide with a particle size exceeding 300 nm, the content of silicon dioxide is 10-35% by mass based on the total solid content of the composition, the epoxy resin (C) is only a dicyclopentadiene epoxy resin or a naphthalene epoxy resin having an epoxy equivalent of 100-250 g/eq, and the ratio of the number of epoxy groups in the epoxy resin (C) to the number of carboxyl groups in the resin (A) containing a carboxyl group is 1.9-2.5. A dry film characterized by having a resin layer, which is obtained by applying a hardening resin composition as claimed in claim 1 on a film and drying it. A hardened product, characterized by being obtained by hardening the hardening resin composition as in claim 1, or the resin layer of the dry film as in claim 2. An electronic component characterized by having a hardened material as described in claim 3.