JP7339103B2 - Curable resin composition, dry film, cured product, and electronic component - Google Patents

Description

TECHNICAL FIELD The present invention relates to curable resin compositions, dry films, cured products, and electronic parts.

2. Description of the Related Art In recent years, as the performance of electronic devices has improved, the density of semiconductor packages has increased. Due to such a demand for higher density, miniaturization of patterns in an insulating hardened material layer such as a solder resist is required.

On the other hand, in the method of manufacturing a wiring board in which a part of the connection pad is exposed from the solder resist layer, the solder resist layer is once thinned by exposing and developing to the extent that the connection pad is not exposed, and then further exposed. , a manufacturing method is known in which a part of the connection pad is exposed by developing (Patent Document 1).

JP 2016-006809 A

In order to improve the resolution of the resin composition for the purpose of miniaturizing the pattern, it is conceivable to reduce the amount of the inorganic filler contained in the resin composition. It becomes difficult to obtain the desired effect by blending the inorganic filler.
Therefore, the inventors of the present invention developed only the upper portion of the connection pad to thin it once, as in the manufacturing method described in Patent Document 1, and then exposed and developed to a fine pattern. A study was made to suppress deterioration of resolution due to halation. By using this process, high resolution can be obtained on the connection pads, and reliability can be ensured in other portions.
However, it is difficult to control development for thinning, and there are problems such as delamination in unexposed and exposed areas, re-adhesion, and poor tackiness in unexposed areas. If delamination or reattachment occurs in the unexposed or exposed areas, problems such as reduced connection reliability and poor appearance may occur. contamination may occur.

Accordingly, an object of the present invention is to provide a curable resin composition that has excellent developability without problems such as delamination in resolution and thin film formation, and that provides a cured product having excellent HAST resistance and crack resistance, and a curable resin composition obtained from the composition. An object of the present invention is to provide a dry film having a resin layer, a cured product of the composition or the resin layer of the dry film, and an electronic component having the cured product.

As a result of intensive studies aimed at realizing the above object, the present inventors have found that the above problems can be solved by blending an inorganic filler having a specific particle size distribution, and have completed the present invention.

That is, the curable resin composition of the present invention is a curable resin composition containing (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, and (C) an inorganic filler, wherein the (C ) The particle size distribution of the inorganic filler is characterized by satisfying the following conditions (1) to (3).
(1) D50 particle size value = 1.0 µm or less (2) (D90 particle size value) / (D10 particle size value) = 5.0 or less (3) ((D90 particle size value) - (D50 particle size value) ) / ((D50 particle size value) - (D10 particle size value)) = 0.5 to 5.0

In the curable resin composition of the present invention, it is preferable that the particle size distribution of the inorganic filler (C) further satisfies the following condition (4).
(4) D50 frequency = 7.0% or more

The curable resin composition of the present invention is preferably used in a method for producing a cured product including a step of partially thinning a resin layer made of the curable resin composition with a developer.

In the curable resin composition of the present invention, the content of the inorganic filler (C) is preferably 25 to 70% by mass based on the total amount of the curable resin composition excluding the solvent.

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

The cured product of the present invention is characterized by being obtained by curing the curable resin composition or the resin layer of the dry film.

The electronic component of the present invention is characterized by having the cured product.

According to the present invention, there is provided a curable resin composition capable of obtaining a cured product having excellent resolution and thin film formation without problems such as delamination, and having excellent HAST resistance and crack resistance, and a resin obtained from the composition. A dry film having a layer, a cured product of the resin layer of the composition or the dry film, and an electronic component having the cured product can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows typically one embodiment of the method of forming the pattern of hardened|cured material by pattern exposure and development, after thinning the resin layer which consists of a curable resin composition with a developer. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows typically one embodiment of the conventional method of forming the pattern of hardened|cured material by pattern exposure and development of the resin layer which consists of curable resin compositions, without thinning.

The curable resin composition of the present invention is a curable resin composition containing (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, and (C) an inorganic filler, wherein the (C) inorganic The particle size distribution of the filler is characterized by satisfying the following conditions (1) to (3). (C) The particle size distribution of the inorganic filler satisfies the following conditions (1) to (3), so that excellent developability without problems such as delamination in resolution and thin film formation, and curing with excellent HAST resistance and crack resistance can get things.
(1) D50 particle size value = 1.0 µm or less (2) (D90 particle size value) / (D10 particle size value) = 5.0 or less (3) ((D90 particle size value) - (D50 particle size value) ) / ((D50 particle size value) - (D10 particle size value)) = 0.5 to 5.0

In the present invention, the particle size distribution of the inorganic filler (C) is a particle size distribution including not only the particle size of the primary particles but also the particle size of the secondary particles (aggregate), and is a volume distribution measured by a laser diffraction method. be. Microtrac MT3300EXII manufactured by Microtrac Bell Co., Ltd. can be used as a measuring device using the laser diffraction method. The D50 frequency is obtained from the cumulative volume ratio of each particle size obtained by the above measuring device. It is the frequency of particle diameters at which the cumulative volume ratio is 50%.

Condition (1) (that is, D50 particle size) is preferably 0.8 μm or less, more preferably 0.5 μm or less, from the viewpoints of developability control, resolution and melt viscosity at 40°C. The lower limit is not particularly limited, and is, for example, 0.1 μm or more, and more preferably 0.2 μm or more from the viewpoint of developability control and melt viscosity at 90° C., which will be described later.
Condition (2) (that is, (D90 particle size value) / (D10 particle size value)) is preferably 3.0 to 4.5 from the viewpoint of the balance between melt viscosity and resolution at 40 ° C. and 90 ° C. is.
Condition (3) (that is, ((D90 particle size value) - (D50 particle size value)) / ((D50 particle size value) - (D10 particle size value))) is the melt viscosity at 40 ° C. and 90 ° C. It is preferably 0.8 to 4.5, more preferably 1.5 to 4.0, from the viewpoint of balance of resolution.

Condition (4) (that is, D50 frequency) is preferably 7.0% or more, more preferably 8.0% or more from the viewpoint of the balance between melt viscosity at 40°C and 90°C and resolution, Even more preferably, it is 9.0% or more.

Further, since the curable resin composition of the present invention is more excellent in tackiness, the melt viscosity at 40° C. is preferably 1.0×10 ⁴ dPa·s or more, more preferably 8.0×10 ⁵ dPa. * It is more preferable that it is s or more. For example, (1) the D50 particle size value is 0.6 μm or less, and the amount of the inorganic filler is 40% by mass or more based on the total amount of the curable resin composition excluding the solvent. It is excellent in developability control, resolution, etc. while increasing viscosity. On the other hand, the melt viscosity at 90° C. is preferably less than 1.0×10 ³ dPa·s, and preferably 5.0×10 ¹ dPa·s or less, from the viewpoint of embedding in fine circuit patterns. more preferred. For example, (1) the D50 particle size value is 0.2 μm or more, and the amount of the inorganic filler is 60% by mass or less based on the total amount of the curable resin composition excluding the solvent. It is excellent in developability control and resolution while keeping the viscosity low.

The curable resin composition of the present invention can be suitably used in a method for producing a cured product including a step of partially thinning with a developer. For example, as shown in FIG. 1, after a resin layer 3 made of a curable resin composition is formed on a substrate 1 on which a conductive circuit 2 is formed (FIG. 1(1)), through a first negative mask 4, Partial exposure is performed to cure the exposed portion (FIG. 1(2)). After that, development is performed in a time shorter than the breakpoint (shortest development time) to partially thin the resin layer, ie, only the upper portion of the connection pad (FIG. 1(3)). The thin film is exposed in a fine pattern through a negative mask 5 (FIG. 1(4)), and then developed to form a cured product pattern with excellent resolution on the connection pads. (Fig. 1(5)). If a pattern of a cured product is formed on the connection pad without going through the thinning process for the resin layer on the substrate (Fig. 2 (1)) as in the conventional method, gouges due to halation occur in the opening. (2) in FIG. 2), it was difficult to form a pattern with excellent resolution. In addition, by partially thinning with the developing solution, the reliability of the fine wiring portion is improved as compared with the conventional case where the resin layer on the substrate is formed of a thin dry film.

Each component of the curable resin composition of the present invention is described below. In this specification, (meth)acrylate is a generic term for acrylate, methacrylate and mixtures thereof, and the same applies to other similar expressions.

[(A) Carboxyl Group-Containing Resin]
As the carboxyl group-containing resin, conventionally known various carboxyl group-containing resins having a carboxyl group in the molecule can be used. In particular, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond in the molecule is preferable from the viewpoint of photocurability and development resistance. The ethylenically unsaturated double bonds are preferably derived from acrylic acid or methacrylic acid or derivatives thereof. When only a carboxyl group-containing resin having no ethylenically unsaturated double bonds is used, in order to make the composition photocurable, a compound having a plurality of ethylenically unsaturated groups in the molecule, i.e., photo It is necessary to use a reactive monomer together.
Specific examples of the carboxyl group-containing resin include the following compounds (both oligomers and polymers).

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth)acrylic acid and an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth)acrylate, isobutylene, or the like.

(2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates; Carboxyl group-containing urethane resins obtained by polyaddition reaction of diol compounds such as polyols, polyester polyols, polyolefin polyols, acrylic polyols, bisphenol A alkylene oxide adduct diols, and compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups.

(3) Diisocyanate compounds such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates, polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic polyols, and bisphenol A-based A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride with the terminal of a urethane resin obtained by a polyaddition reaction of a diol compound such as an alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(4) Diisocyanate and 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, bixylenol type epoxy resin, biphenol type epoxy resin ( A carboxyl group-containing photosensitive urethane resin produced by a polyaddition reaction of a meth)acrylate or its partial acid anhydride modified product, a carboxyl group-containing dialcohol compound and a diol compound.

(5) During the synthesis of the resin of (2) or (4), a compound having one hydroxyl group and one or more (meth)acryloyl groups in the molecule such as hydroxyalkyl (meth)acrylate is added, and the terminal ( Meta) acrylated carboxyl group-containing photosensitive urethane resin.

(6) During the synthesis of the resin of (2) or (4), one isocyanate group and one or more (meth)acryloyl groups in the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate A carboxyl group-containing photosensitive urethane resin that is terminally (meth)acrylated by adding a compound having

(7) A carboxyl group-containing photosensitive resin obtained by reacting (meth)acrylic acid with a polyfunctional (solid) epoxy resin having a functionality of 2 or more and adding a dibasic acid anhydride to the hydroxyl group present in the side chain.

(8) A carboxyl obtained by reacting (meth)acrylic acid with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl group of a bifunctional (solid) epoxy resin with epichlorohydrin, and adding a dibasic acid anhydride to the resulting hydroxyl group. Group-containing photosensitive resin.

(9) A bifunctional oxetane resin is reacted with a dicarboxylic acid such as adipic acid, phthalic acid, and hexahydrophthalic acid, and the resulting primary hydroxyl group is treated with a dibasic such as phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride. Carboxyl group-containing polyester resin to which acid anhydride is added.

(10) an epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, such as p-hydroxyphenethyl alcohol; Maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and adipine are reacted with an unsaturated group-containing monocarboxylic acid such as acrylic acid, and the alcoholic hydroxyl group of the resulting reaction product is treated with A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride such as an acid.

(11) A reaction product obtained by reacting a reaction product obtained by reacting a compound having multiple phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide with a monocarboxylic acid containing an unsaturated group. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic acid anhydride with a substance.

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

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

(14) A carboxyl group-containing photosensitive resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in one molecule to the resins of (1) to (13).

(A) The carboxyl group-containing resin is not limited to those listed above, and may be used singly or in combination of two or more.

(A) The acid value of the carboxyl group-containing resin is preferably 20 to 200 mgKOH/g. When the acid value of (A) the carboxyl group-containing resin is 20 to 200 mgKOH/g, the pattern formation of the cured product is facilitated. More preferably, it is 50 to 130 mgKOH/g.

The weight-average molecular weight of (A) the carboxyl group-containing resin varies depending on the resin skeleton, but is generally in the range of 2,000 to 150,000, preferably 5,000 to 100,000. When the weight average molecular weight is 2,000 or more, the development resistance of the film in the exposed area is improved and the resolution is excellent. On the other hand, when the weight average molecular weight is 150,000 or less, the solubility of the unexposed area is good, the resolution is excellent, and the storage stability may be improved. A weight average molecular weight can be measured by a gel permeation chromatography.

The amount of the carboxyl group-containing resin (A) is, for example, 5 to 50% by mass, preferably 10 to 40% by mass, based on the total amount of the curable resin composition excluding the solvent. The coating film strength can be improved by making it 5% by mass or more, preferably 10% by mass or more. Further, when the content is 50% by mass or less, preferably 40% by mass or less, the viscosity becomes appropriate and the workability is improved.

[(B) Photoinitiator]
As the photopolymerization initiator (B), any photopolymerization initiator known as a photopolymerization initiator or a photoradical generator can be used. For example, bis-(2,6-dichlorobenzoyl ) phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2 ,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine bisacylphosphine oxides such as oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide and bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide;2 ,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphine acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphine monoacylphosphine oxides such as finic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 1-hydroxy-cyclohexylphenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2 -hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propane- Hydroxyacetophenones such as 1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one; benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n -benzoins such as butyl ether; benzoin alkyl ethers; benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone and other benzophenones; acetophenone, 2,2 -dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2- Morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-(dimethylamino)-2-[(4-methylphenyl)methyl)-1- Acetophenones such as [4-(4-morpholinyl)phenyl]-1-butanone and N,N-dimethylaminoacetophenone; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4- Thioxanthones such as diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; , 2-aminoanthraquinone and other anthraquinones; acetophenone dimethyl ketal, benzyl dimethyl ketal and other ketals; ethyl-4-dimethylaminobenzoate, 2-(dimethylamino)ethyl benzoate, p-dimethylbenzoic acid ethyl ester and other benzoic acids Esters; 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H- oxime esters such as carbazol-3-yl]-,1-(O-acetyloxime); bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H -pyrrol-1-yl)phenyl)titanium, bis(cyclopentadienyl)-bis[2,6-difluoro-3-(2-(1-pyrr-1-yl)ethyl)phenyl]titanium, etc. phenyl disulfide 2-nitrofluorene, butyroin, anisoine ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide and the like. (B) A photoinitiator may be used individually by 1 type, and may be used in combination of 2 or more type.

The amount of the photopolymerization initiator (B) to be blended is preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin (A). When the amount is 0.5 parts by mass or more, the surface curability is improved, and when the amount is 20 parts by mass or less, halation is less likely to occur and better resolution can be obtained.

[(C) inorganic filler]
(C) The inorganic filler is not particularly limited as long as it satisfies the above conditions (1) to (3), and known and commonly used fillers such as silica such as amorphous silica, crystalline silica, fused silica, and spherical silica, Neuburg Silica, aluminum hydroxide, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica, aluminum oxide, barium sulfate, barium titanate, iron oxide, non-fibrous glass, hydrotalcite, mineral wool , aluminum silicate, calcium silicate, and zinc oxide. Among them, silica is preferable, and spherical silica is more preferable because it has a small surface area and is less likely to cause cracks because stress is dispersed over the entire surface.

(C) The inorganic filler may be subjected to a photoreactive surface treatment so as to have a vinyl group, a styryl group, a methacrylic group, an acrylic group, or the like as a photocurable reactive group. A vinyl group is particularly preferred. In addition, as thermosetting reactive groups, hydroxyl group, carboxyl group, isocyanate group, amino group, imino group, epoxy group, oxetanyl group, mercapto group, methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, oxazoline group etc., and in this case, amino groups and epoxy groups are particularly preferred. Furthermore, (C) the inorganic filler may have two or more curable reactive groups. (C) The inorganic filler is preferably surface-treated silica. By including surface-treated silica, TCT resistance can be improved.

(C) The introduction method for introducing a curable reactive group onto the surface of the inorganic filler is not particularly limited, and may be introduced using a known and commonly used method. The surface of the inorganic filler may be treated with a coupling agent or the like having a reactive group.

(C) Surface treatment with a coupling agent is preferable as the surface treatment of the inorganic filler. A silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, or the like can be used as the coupling agent. Among them, silane coupling agents are preferred.

As the silane coupling agent, a silane coupling agent capable of introducing a curing reactive group into (C) the inorganic filler is preferable. Examples of the silane coupling agent capable of introducing a thermosetting reactive group include a silane coupling agent having an epoxy group, a silane coupling agent having an amino group, a silane coupling agent having a mercapto group, and a silane coupling agent having an isocyanate group. Among them, a silane coupling agent having an epoxy group is more preferable. Silane coupling agents capable of introducing photocurable reactive groups include silane coupling agents having a vinyl group, silane coupling agents having a styryl group, silane coupling agents having a methacryl group, and silane coupling agents having an acryl group. Among them, a silane coupling agent having a methacrylic group is more preferable.

(C) When the inorganic filler is surface-treated, it may be blended in the curable resin composition of the present invention in a surface-treated state, and the surface-untreated (C) inorganic filler and the surface treatment agent are separated. Although the inorganic filler (C) may be surface-treated in the composition after blending, it is preferable to blend the inorganic filler (C) which has been surface-treated in advance. By blending the (C) inorganic filler that has been surface-treated in advance, it is possible to prevent deterioration in crack resistance, etc., due to the surface treatment agent not consumed in the surface treatment, which may remain when blended separately. In the case of surface treatment in advance, it is preferable to blend a pre-dispersion liquid in which the (C) inorganic filler is pre-dispersed in the solvent or resin component, and the surface-treated (C) inorganic filler is pre-dispersed in the solvent, and the pre-dispersion liquid is prepared. is blended into the composition, or the surface-untreated (C) inorganic filler is sufficiently surface-treated when pre-dispersed in a solvent, and then blended with the composition.

(C) The method for preparing the particle size distribution of the inorganic filler is not particularly limited, and any method may be used as long as the dispersion satisfies the above conditions (1) to (3). For example, using a bead mill, a rocking mill, a jet mill, etc., the particles are dispersed at a rotational speed of 500 rpm or higher, a pump output of 10% or higher, and a temperature of 40° C. or higher during dispersion.

The amount of the inorganic filler (C) is preferably 25 to 70% by mass, more preferably 30 to 60% by mass, based on the total amount of the curable resin composition excluding the solvent.

(Thermosetting resin)
When a thermosetting resin is contained, the heat resistance of the cured product is improved, and the adhesiveness to the substrate is improved. As the thermosetting resin, known and commonly used thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, epoxy compounds, polyfunctional oxetane compounds, and episulfide resins can be used. . Among these, epoxy compounds, polyfunctional oxetane compounds, compounds having two or more thioether groups in the molecule, that is, episulfide resins, are preferred, and epoxy compounds are more preferred. A thermosetting resin can be used individually by 1 type or in combination of 2 or more types.

The epoxy compound is a compound having an epoxy group, and any conventionally known compound can be used. Examples include polyfunctional epoxy compounds having multiple epoxy groups in the molecule. In addition, a hydrogenated epoxy compound may be used.

As polyfunctional epoxy compounds, epoxidized vegetable oil; bisphenol A type epoxy resin; hydroquinone type epoxy resin; bisphenol type epoxy resin; thioether type epoxy resin; brominated epoxy resin; type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidylamine type epoxy resin; hydantoin type epoxy resin; alicyclic epoxy resin; Bisphenol S type epoxy resin; bisphenol A novolac type epoxy resin; tetraphenylolethane type epoxy resin; heterocyclic epoxy resin; diglycidyl phthalate resin; Glycidyl methacrylate copolymer epoxy resin; cyclohexyl maleimide and glycidyl methacrylate copolymer epoxy resin; epoxy-modified polybutadiene rubber derivative; CTBN-modified epoxy resin, etc., but not limited to these . These epoxy resins can be used singly or in combination of two or more.

Examples of polyfunctional oxetane compounds include bis[(3-methyl-3-oxetanylmethoxy)methyl]ether, bis[(3-ethyl-3-oxetanylmethoxy)methyl]ether, 1,4-bis[(3- methyl-3-oxetanylmethoxy)methyl]benzene, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, (3-methyl-3-oxetanyl)methyl acrylate, (3-ethyl-3- Oxetanyl)methyl acrylate, (3-methyl-3-oxetanyl)methyl methacrylate, (3-ethyl-3-oxetanyl)methyl methacrylate, and polyfunctional oxetanes such as their oligomers or copolymers, as well as oxetane alcohols and novolac resins , poly(p-hydroxystyrene), cardo-type bisphenols, calixarenes, calixresorcinarenes, and etherified products with resins having a hydroxyl group such as silsesquioxane. Other examples include copolymers of unsaturated monomers having an oxetane ring and alkyl (meth)acrylates.

Bisphenol A type episulfide resin etc. are mentioned as a compound which has several cyclic thioether groups in a molecule|numerator. Also, an episulfide resin obtained by replacing the oxygen atom of the epoxy group of the novolac type epoxy resin with a sulfur atom by using a similar synthesis method can be used.

Amino resins such as melamine derivatives and benzoguanamine derivatives include methylol melamine compounds, methylol benzoguanamine compounds, methylol glycoluril compounds and methylol urea compounds.

A polyisocyanate compound can be blended as the isocyanate compound. Polyisocyanate compounds include 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, m-xylylene diisocyanate and aromatic polyisocyanates such as 2,4-tolylene isocyanate dimer; aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylenebis(cyclohexyl isocyanate) and isophorone diisocyanate; alicyclic polyisocyanates such as bicycloheptane triisocyanate; and adducts, biurets and isocyanurates of the above-mentioned isocyanate compounds.

As the blocked isocyanate compound, an addition reaction product of an isocyanate compound and an isocyanate blocking agent can be used. Examples of the isocyanate compound that can react with the isocyanate blocking agent include the aforementioned polyisocyanate compounds. Examples of isocyanate blocking agents include phenolic blocking agents; lactam blocking agents; active methylene blocking agents; alcohol blocking agents; oxime blocking agents; mercaptan blocking agents; Amine-based blocking agents; imidazole-based blocking agents; imine-based blocking agents, and the like.

The content of the thermosetting resin is preferably 10 to 100 parts by mass per 100 parts by mass of the carboxyl group-containing resin (A). In particular, the amount of the thermosetting resin having two or more cyclic (thio)ether groups in the molecule is the amount of (E) the thermosetting resin per equivalent of the carboxyl group of (A) the carboxyl group-containing resin. The amount of the cyclic (thio)ether group contained is preferably in the range of 0.6 to 2.5 equivalents.

(Compound having an ethylenically unsaturated bond)
The curable resin composition of the present invention may contain a compound having an ethylenically unsaturated bond such as a photopolymerizable oligomer or a photopolymerizable vinyl monomer.

Examples of photopolymerizable oligomers include unsaturated polyester-based oligomers and (meth)acrylate-based oligomers. (Meth)acrylate oligomers include epoxy (meth)acrylates such as phenol novolac epoxy (meth)acrylate, cresol novolac epoxy (meth)acrylate, bisphenol type epoxy (meth)acrylate, urethane (meth)acrylate, epoxyurethane (meth)acrylate, ) acrylates, polyester (meth)acrylates, polyether (meth)acrylates, polybutadiene-modified (meth)acrylates, and the like.

Examples of photopolymerizable vinyl monomers include known and commonly used monomers, for example, styrene derivatives such as styrene, chlorostyrene and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate and vinyl benzoate; vinyl isobutyl ether, vinyl- vinyl ethers such as n-butyl ether, vinyl-t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinylcyclohexyl ether, ethylene glycol monobutyl vinyl ether, triethylene glycol monomethyl vinyl ether; acrylamide, (Meth)acrylamides such as methacrylamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, N-butoxymethylacrylamide; triallyl isocyanurate, diallyl phthalate, Allyl compounds such as diallyl isophthalate; 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, etc. (meth)acrylic acid esters; hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, pentaerythritol tri(meth)acrylate and other hydroxyalkyl (meth)acrylates; methoxyethyl (meth)acrylate, ethoxyethyl Alkoxyalkylene glycol mono (meth) acrylates such as (meth) acrylate; ethylene glycol di (meth) acrylate, butanediol di (meth) acrylates, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di ( Alkylene polyol poly(meth)acrylates such as meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate; diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate; Polyoxyalkylene glycol poly(meth)acrylates such as (meth)acrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane tri(meth)acrylate; Poly(meth)acrylates; and isocyanurate-type poly(meth)acrylates such as tris[(meth)acryloxyethyl]isocyanurate. These may be used singly or in combination of two or more according to the required properties.

The compounding amount of the compound having an ethylenically unsaturated bond is preferably 3 to 40 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin (A). When it is 3 parts by mass or more, the surface curability is improved, and when it is 40 parts by mass or less, halation is suppressed. More preferably, it is 5 to 30 parts by mass.

(Thermosetting catalyst)
The curable resin composition of the present invention preferably contains a thermosetting catalyst. Such thermosetting catalysts include, for example, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. , 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N amine compounds such as -dimethylbenzylamine and 4-methyl-N,N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Also, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as S-triazine/isocyanuric acid adducts and 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid adducts can also be used, and these adhesion-imparting agents are preferred. A compound that also functions is used in conjunction with a thermosetting catalyst. One of the thermosetting catalysts may be used alone, or two or more thereof may be used in combination.

The amount of the thermosetting catalyst compounded is preferably 0.5 to 10 parts by mass, more preferably 1.0 to 5 parts by mass, per 100 parts by mass of the carboxyl group-containing resin (A). When it is 0.5 parts by mass or more, the reliability is improved, and when it is 10 parts by mass or less, outgassing can be suppressed.

(coloring agent)
The curable resin composition of the present invention may contain a coloring agent. As the coloring agent, known coloring agents such as red, blue, green, yellow, black, and white can be used, and any of pigments, dyes, and pigments can be used. However, it is preferable not to contain a halogen from the viewpoint of environmental load reduction and influence on the human body. One colorant may be used alone, or two or more colorants may be used in combination.

The amount of the coloring agent to be added is not particularly limited, but is preferably 10 parts by mass or less, particularly preferably 0.1 to 5 parts by mass, per 100 parts by mass of the carboxyl group-containing resin (A).

(Organic solvent)
The curable resin composition of the present invention can contain an organic solvent for the purpose of preparing the composition and adjusting the viscosity when applied to a substrate or carrier film. Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether; , dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbi Esters such as tall acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha; Conventional organic solvents can be used. These organic solvents can be used alone or in combination of two or more.

(Other optional ingredients)
Furthermore, the curable resin composition of the present invention may be blended with other known and commonly used additives in the field of electronic materials. Other additives include thermal polymerization inhibitors, ultraviolet absorbers, curing agents, silane coupling agents, plasticizers, flame retardants, antistatic agents, anti-aging agents, antibacterial/antifungal agents, antifoaming agents, and leveling agents. , thickener, adhesion imparting agent, thixotropy imparting agent, photoinitiator aid, sensitizer, thermoplastic resin, organic filler, release agent, surface treatment agent, dispersant, dispersion aid, surface modifier , stabilizers, phosphors, and the like.

The curable resin composition of the present invention may be used as a dry film or as a liquid. When used as a liquid, it may be one-liquid or two-liquid or more.

Next, the dry film of the present invention has a resin layer obtained by coating and drying the curable resin composition of the present invention on a carrier film. When forming a dry film, first, the curable resin composition of the present invention is diluted with the above organic solvent to adjust the viscosity to an appropriate value, and then a comma coater, blade coater, lip coater, rod coater, and squeeze coater are used. , a reverse coater, a transfer roll coater, a gravure coater, a spray coater, or the like to a uniform thickness on the carrier film. After that, the applied composition is usually dried at a temperature of 40 to 130° C. for 1 to 30 minutes to form a resin layer. The coating thickness is not particularly limited, but is generally selected appropriately within the range of 3 to 150 μm, preferably 5 to 60 μm, in terms of film thickness after drying.

As the carrier film, a plastic film is used, and for example, a polyester film such as polyethylene terephthalate (PET), a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film, or the like can be used. The thickness of the carrier film is not particularly limited, but is generally selected appropriately within the range of 10 to 150 μm. More preferably, it is in the range of 15 to 130 μm.

After forming the resin layer composed of the curable resin composition of the present invention on the carrier film, for the purpose of preventing dust from adhering to the surface of the resin layer, a peelable cover is further placed on the surface of the resin layer. It is preferred to laminate the films. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, surface-treated paper, or the like can be used. Any cover film may be used as long as the adhesive force is smaller than the adhesive force between the resin layer and the carrier film when the cover film is peeled off.

In the present invention, the curable resin composition of the present invention may be coated on the cover film and dried to form a resin layer, and a carrier film may be laminated on the surface of the resin layer. That is, as the film to which the curable resin composition of the present invention is applied when producing the dry film in the present invention, either a carrier film or a cover film may be used.

The electronic component of the present invention has a cured product obtained from the curable resin composition or the resin layer of the dry film of the present invention. As a method for producing an electronic component using the curable resin composition of the present invention, a conventionally known method may be used. The curable resin composition of the present invention can be suitably used in a production method including a step of curing. For example, the curable resin composition of the present invention is adjusted to a viscosity suitable for the coating method using the above organic solvent, and is coated on the substrate by a dip coating method, a flow coating method, a roll coating method, a bar coater method, After coating by a method such as screen printing or curtain coating, the organic solvent contained in the composition is volatilized and dried (temporary drying) at a temperature of 60 to 100° C. to form a tack-free resin layer. In the case of a dry film, the resin layer is formed on the substrate by laminating it on the substrate with a laminator or the like so that the resin layer is in contact with the substrate, and then peeling off the carrier film.

Examples of the substrate include printed wiring boards and flexible printed wiring boards on which circuits are formed in advance using copper or the like, paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth/non-woven cloth epoxy, glass cloth/paper epoxy. , Synthetic fiber epoxy, fluororesin, polyethylene, polyphenylene ether, polyphenylene oxide, cyanate, and other materials such as copper-clad laminates for high-frequency circuits, and copper-clad laminates of all grades (FR-4, etc.) Plates, metal substrates, polyimide films, PET films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer plates and the like can also be used.

Volatilization drying performed after applying the curable resin composition of the present invention can be performed using a hot air circulation drying oven, an IR oven, a hot plate, a convection oven, etc. A method of bringing hot air into countercurrent contact and a method of blowing hot air onto the support from a nozzle) can be used.

After forming a resin layer on the printed wiring board, it is selectively exposed to active energy rays through a photomask having a predetermined pattern, and the unexposed area is treated with a dilute alkaline aqueous solution (e.g., 0.3 to 3% by mass sodium carbonate aqueous solution). ), the resin layer is partially thinned by developing in a time shorter than the break point (shortest development time). After forming the thin film, it is selectively exposed to active energy rays through a photomask having a predetermined pattern, and the unexposed area is developed with a dilute alkaline aqueous solution (eg, 0.3 to 3% by mass aqueous solution of sodium carbonate) to obtain a cured product. form a pattern of Furthermore, the cured product is cured by heat after irradiation with active energy rays (e.g., 100 to 220 ° C), or by irradiation with active energy rays after heat curing, or by final curing (main curing) only by heat curing. Forms a cured film with excellent properties such as toughness and hardness.
When the curable resin composition of the present invention contains a photobase generator, it is preferably heated after exposure and before development. Heating for 60 minutes is preferred.

As the exposure machine used for the active energy ray irradiation, if it is an apparatus equipped with a high pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc., and irradiating the active energy ray in the range of 350 to 450 nm Well, in addition, a direct writing device (eg, a laser direct imaging device that writes an image with a laser directly from CAD data from a computer) can also be used. The lamp light source or laser light source of the direct drawing machine may have a maximum wavelength in the range of 350 to 450 nm. The amount of exposure for image formation varies depending on the film thickness and the like, but can generally be in the range of 10-1000 mJ/cm ² , preferably in the range of 20-800 mJ/cm ² .

Examples of the developing method include a dipping method, a shower method, a spray method, a brush method, and the like. Alkaline aqueous solutions such as ammonia and amines can be used.

The curable resin composition of the present invention is preferably used to form a cured film on a printed wiring board, more preferably used to form a permanent film, and more preferably a solder resist, Used to form interlayer insulating layers, coverlays. In addition, according to the curable resin composition of the present invention, it is possible to obtain a cured product excellent in resolution, HAST resistance and TCT resistance. It can be suitably used for forming wiring boards, eg package substrates, especially permanent coatings (especially solder resists) for FC-BGA.

EXAMPLES The present invention will be described in more detail below using examples, but the present invention is not limited to the following examples. In the following description, "parts" and "%" are based on mass unless otherwise specified. The compounding amount of each component described in the table is the mass part of the solid content not containing the solvent.

[Synthesis of carboxyl group-containing resin]
(Synthesis Example 1: Carboxyl Group-Containing Resin (A)-1)
A flask equipped with a condenser and a stirrer was charged with 456 parts of bisphenol A, 228 parts of water, and 649 parts of 37% formalin. °C for 10 hours. After completion of the reaction, the mixture was cooled to 40°C and neutralized to pH 4 with a 37.5% aqueous solution of phosphoric acid while maintaining the temperature below 40°C. After that, the mixture was allowed to stand and the water layer was separated. After separation, 300 parts of methyl isobutyl ketone was added and dissolved uniformly, then washed with 500 parts of distilled water three times, and water, solvent and the like were removed under reduced pressure at a temperature of 50°C or lower. The obtained polymethylol compound was dissolved in 550 parts of methanol to obtain 1230 parts of a methanol solution of the polymethylol compound.
A portion of the obtained methanol solution of the polymethylol compound was dried in a vacuum dryer at room temperature to find that the solid content was 55.2%.
500 parts of the obtained methanol solution of the polymethylol compound and 440 parts of 2,6-xylenol were placed in a flask equipped with a condenser and a stirrer and dissolved uniformly at 50°C. After uniformly dissolving, methanol was removed under reduced pressure at a temperature of 50°C or less. After that, 8 parts of oxalic acid was added and reacted at 100° C. for 10 hours. After completion of the reaction, distillate was removed at 180° C. under reduced pressure of 50 mmHg to obtain 550 parts of novolac resin A.
130 parts of novolak resin A, 2.6 parts of 50% sodium hydroxide aqueous solution, toluene/methyl isobutyl ketone (mass ratio = 2/1) were placed in an autoclave equipped with a thermometer, a nitrogen introduction device/alkylene oxide introduction device and a stirring device. 100 parts of propylene oxide was charged, and the inside of the system was purged with nitrogen while stirring, then the temperature was raised, and 60 parts of propylene oxide was gradually introduced at 150° C. and 8 kg/cm ² to react. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg/cm ² and then cooled to room temperature. 3.3 parts of a 36% hydrochloric acid aqueous solution was added to and mixed with this reaction solution to neutralize the sodium hydroxide. This neutralization reaction product was diluted with toluene, washed with water three times, and the solvent was removed by an evaporator to give a hydroxyl value of 189 g/eq. A propylene oxide adduct of novolac resin A was obtained. It was found that an average of 1 mol of propylene oxide was added per equivalent of phenolic hydroxyl group.
189 parts of the propylene oxide adduct of novolac resin A, 36 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.1 part of hydroquinone monomethyl ether and 140 parts of toluene were added to a stirrer, a thermometer and an air blowing tube. was charged into a reactor equipped with, stirred while blowing air, heated to 115 ° C., reacted for an additional 4 hours while distilling off the water produced by the reaction as an azeotropic mixture with toluene, and then cooled to room temperature. cooled. The resulting reaction solution was washed with a 5% NaCl aqueous solution, toluene was removed by distillation under reduced pressure, and diethylene glycol monoethyl ether acetate was added to obtain an acrylate resin solution with a solid content of 67%.
Next, 322 parts of the obtained acrylate resin solution, 0.1 part of hydroquinone monomethyl ether, and 0.3 parts of triphenylphosphine were charged into a four-necked flask equipped with a stirrer and a reflux condenser, and the mixture was heated to 110°C. , 60 parts of tetrahydrophthalic anhydride was added, reacted for 4 hours, cooled, and taken out. The solution of the photosensitive carboxyl group-containing resin (A)-1 thus obtained had a solid content of 70% and a solid content acid value of 81 mgKOH/g. Hereinafter, the solution of this carboxyl group-containing resin is referred to as resin solution (A)-1.

(Synthesis Example 2: Carboxyl Group-Containing Resin (A)-2)
An autoclave equipped with a thermometer, a nitrogen introduction device/alkylene oxide introduction device and a stirrer was charged with 119.4 parts of a novolak cresol resin (Showol CRG951 manufactured by Showa Denko Co., Ltd., OH equivalent: 119.4) and 1.5 parts of potassium hydroxide. 19 parts and 119.4 parts of toluene were introduced, the inside of the system was replaced with nitrogen while stirring, and the temperature was raised. Next, 63.8 parts of propylene oxide was gradually added dropwise and reacted at 125-132° C. and 0-4.8 kg/cm ² for 16 hours. After cooling to room temperature, 1.56 parts of 89% phosphoric acid was added to and mixed with the reaction solution to neutralize potassium hydroxide. 9 g/eq.) of a novolak-type cresol resin propylene oxide reaction solution was obtained. This was an average addition of 1.08 moles of propylene oxide per equivalent of phenolic hydroxyl group.
293.0 parts of the propylene oxide reaction solution of the obtained novolak-type cresol resin, 43.2 parts of acrylic acid, 11.53 parts of methanesulfonic acid, 0.18 parts of methylhydroquinone and 252.9 parts of toluene were mixed with a stirrer at a temperature of The mixture was introduced into a reactor equipped with a meter and an air blowing tube, air was blown in at a rate of 10 ml/min, and reaction was carried out at 110° C. for 12 hours while stirring. As for the water produced by the reaction, 12.6 parts of water was distilled as an azeotrope with toluene. After cooling to room temperature, the resulting reaction solution was neutralized with 35.35 parts of a 15% aqueous sodium hydroxide solution and then washed with water. After that, the toluene was distilled off while substituting 118.1 parts of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak type acrylate resin solution. Next, 332.5 parts of the resulting novolac acrylate resin solution and 1.22 parts of triphenylphosphine were introduced into a reactor equipped with a stirrer, thermometer and air blowing tube, and air was added at a rate of 10 ml/min. 60.8 parts of tetrahydrophthalic anhydride was gradually added while stirring, reacted at 95 to 101° C. for 6 hours, cooled, and taken out. Thus, a solution of photosensitive carboxyl group-containing resin (A)-2 having a solid content of 65% and a solid acid value of 87.7 mgKOH/g was obtained. Hereinafter, the solution of this carboxyl group-containing resin is referred to as resin solution (A)-2.

(Synthesis Example 3: Carboxyl Group-Containing Resin (A)-3)
To 600 g of diethylene glycol monoethyl ether acetate was added 1070 g of an ortho-cresol novolac type epoxy resin (EPICLON N-695 manufactured by DIC, softening point 95°C, epoxy equivalent weight 214, average functional group number 7.6) (number of glycidyl groups (total number of aromatic rings): 5. 0 mol), 360 g (5.0 mol) of acrylic acid, and 1.5 g of hydroquinone were charged, heated to 100° C. with stirring, and uniformly dissolved.
Then, 4.3 g of triphenylphosphine was charged, heated to 110° C. and reacted for 2 hours, then heated to 120° C. and reacted for further 12 hours. 415 g of an aromatic hydrocarbon (Solvesso 150) and 456.0 g (3.0 mol) of tetrahydrophthalic anhydride were added to the resulting reaction solution, reacted at 110° C. for 4 hours, cooled, and photosensitive carboxyl A solution of group-containing resin (A)-3 was obtained. The solid content of the resin solution thus obtained was 65%, and the acid value of the solid content was 89 mgKOH/g. Hereinafter, the solution of this carboxyl group-containing resin is referred to as resin solution (A)-3.

[Preparation of inorganic filler]
(Adjustment Example 1: Inorganic Filler Slurry (C)-1)
50 g of spherical silica particles (Admafine SO-C3 manufactured by Admatechs, average particle size: 800 nm), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) are blended. Stir and disperse with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C. Condition (1) is 0.8 μm, Condition (2). was 4.0, condition (3) was 2.0 and condition (4) was 11.5%. The resulting dispersion is defined as an inorganic filler slurry (C)-1. The particle size distributions (1) to (4) of the obtained inorganic fillers were obtained using Microtrac MT3300EXII manufactured by Microtrac Bell Co., Ltd., with a measurement range of 0.8 nm to 6.54 μm and a channel (Ch) number of 52. are the values given in the table below. The same applies to other inorganic fillers used in Examples and Comparative Examples.

(Adjustment Example 2: Inorganic Filler Slurry (C)-2)
50 g of spherical silica particles (Admafine SO-C2, average particle size: 500 nm, manufactured by Admatechs), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) are blended. Stir and disperse with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C. Condition (1) is 0.5 μm, Condition (2). was 3.3, condition (3) was 3.7 and condition (4) was 8.7%. The resulting dispersion is designated as an inorganic filler slurry (C)-2.

(Adjustment Example 3: Inorganic Filler Slurry (C)-3)
50 g of spherical silica particles (Admafine SO-C1 manufactured by Admatechs, average particle size: 300 nm), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) are blended. Stir and disperse with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C. Condition (1) is 0.3 μm, Condition (2). was 3.7, condition (3) was 1.7 and condition (4) was 9.5%. The resulting dispersion is designated as an inorganic filler slurry (C)-3.

(Adjustment Example 4: Inorganic Filler Slurry (C)-4)
50 g of spherical silica particles (Admanano 100 nm, average particle size: 100 nm, manufactured by Admatechs), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) are blended and stirred, Dispersion treatment was performed with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50°C. 2. A dispersion of 4.0% under condition (3) and 8.5% under condition (4) was obtained. The resulting dispersion is designated as an inorganic filler slurry (C)-4.

(Adjustment Example 5: Inorganic Filler Slurry (C)-5)
50 g of barium sulfate (B-33 manufactured by Sakai Chemical Co., Ltd.), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) were blended and stirred, and a bead mill (K In -8), dispersion treatment was performed at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C., with condition (1) being 0.5 μm, condition (2) being 4.0, and condition (3). was 2.0 and condition (4) was 14.1%. The resulting dispersion is defined as an inorganic filler slurry (C)-5.

(Adjustment Example 6: Inorganic Filler Slurry (R)-1)
50 g of spherical silica particles (Admafine SO-C4, average particle size: 1.2 μm, manufactured by Admatechs), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed and stirred, and dispersion treatment was performed with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C., condition (1) was 1.2 μm, condition ( A dispersion with 2) of 5.0, condition (3) of 3.8 and condition (4) of 7.2% was obtained. The resulting dispersion is defined as an inorganic filler slurry (R)-1.

(Adjustment Example 7: Inorganic Filler Slurry (R)-2)
Spherical silica particles A (Admatex Co., Ltd. Admanano 100 nm, average particle size: 100 nm) 10 g, spherical silica particles B (Admatex Co., Ltd. Admafine SO-C2, average particle size: 500 nm) 30 g, spherical silica particles (Admatex 10 g of ADMAFINE SO-C4 (manufactured by Co., Ltd., average particle diameter: 1.2 μm), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) were blended and stirred, and a bead mill ( BUHLER K-8) at a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C., the condition (1) is 0.5 μm, the condition (2) is 9.0, A dispersion of 4.5% in condition (3) and 5.5% in condition (4) was obtained. The resulting dispersion is designated as an inorganic filler slurry (R)-2.

(Adjustment Example 8: Inorganic Filler Slurry (R)-3)
50 g of spherical silica particles (Admafine SO-C2, average particle size: 500 nm, manufactured by Admatechs), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) are blended. Stir and disperse twice with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 1080 rpm, a pump output of 15%, and a temperature during dispersion of 50 to 60 ° C., condition (1) is 0.5 μm, condition ( A dispersion with 2) of 4.8, condition (3) of 7.2, and condition (4) of 7.2% was obtained. The resulting dispersion is designated as an inorganic filler slurry (R)-3.

(Adjustment Example 9: Inorganic Filler Slurry (R)-4)
Spherical silica particles A (Admatex Co., Ltd. Admanano 100 nm, average particle size: 100 nm) 20 g, spherical silica particles B (Admatex Co., Ltd. Admafine SO-C2, average particle size: 500 nm) 10 g, spherical silica particles (Admatex 20 g of ADMAFINE SO-C4 manufactured by Co., Ltd., average particle size: 1.2 μm), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) were blended and stirred, and the bead mill ( BUHLER K-8) with a rotation speed of 900 rpm, a pump output of 20%, and a temperature during dispersion of 40 to 50 ° C., the condition (1) is 0.5 μm, the condition (2) is 9.5, A dispersion with 2.2% in condition (3) and 3.0% in condition (4) was obtained. The resulting dispersion is designated as an inorganic filler slurry (R)-4.

(Adjustment Example 10: Inorganic Filler Slurry (R)-5)
50 g of spherical silica particles (Admafine SO-C2, average particle size: 500 nm, manufactured by Admatechs), 48 g of PMA as a solvent, and 2 g of a silane coupling agent having a methacrylic group (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) are blended. Stir and disperse with a bead mill (K-8 manufactured by BUHLER) at a rotation speed of 300 rpm, a pump output of 30%, and a temperature during dispersion of 30 to 40 ° C. Condition (1) is 0.8 μm, Condition (2). was 3.8, condition (3) was 0.4 and condition (4) was 10.3%. The resulting dispersion is designated as inorganic filler slurry (R)-5.

[Examples 1 to 12, Comparative Examples 1 to 5]
Various components in the table were blended in proportions (parts by mass) shown in the table, premixed with a stirrer, and then kneaded with a bead mill to prepare a curable resin composition.

<Procedure for preparing dry film for test>
For each of Examples and Comparative Examples, the curable resin composition was applied to a desired thickness using a die coater on a PET film and passed through a drying oven at 60 to 120°C at 5 to 15 m/min. By volatilizing the solvent, a dry film having a resin layer made of the curable resin composition was obtained.

<Procedure for formation, exposure, development and curing of resin layer composed of curable resin composition>
The dry film obtained by the above method was laminated on a test substrate using a vacuum laminator CVP-300 (manufactured by Nikko Materials Co., Ltd.) to form a resin layer composed of a curable resin composition on the test substrate. Using a DXP-3580 (manufactured by ORC, an ultra-high pressure mercury lamp DI exposure machine), this resin layer was exposed to light according to the evaluation items so as to obtain 10 curing stages with a Stouffer 41-stage step tablet. After 10 minutes from the exposure, the PET film was peeled off, and development was performed with a 1 wt % sodium carbonate aqueous solution at 30° C. for a development time twice the break point (shortest development time). After that, the curable resin composition was cured by exposure at 2000 mJ with a UV conveyor (metal halide lamp manufactured by ORC) and heating at 170° C. for 60 minutes in a thermal circulation box furnace.

<Developability control>
Using a dry film having a resin layer thickness of about 30 μm prepared as described above, the above resin layer was formed on a plated copper substrate treated with CZ-8201B at an etching rate of 0.5 μm / m ^2. - In the exposure procedure, a resin layer made of a curable resin composition was formed so as to have a film thickness of about 30 µm, and exposure was performed with an open pattern of 30 mm x 30 mm. After peeling off the PET film, develop with a 1 wt% aqueous sodium carbonate solution at 30°C for development times 1/2 and 2/3 times the break point (shortest development time, i.e., the shortest time to completely remove the unexposed area). did The evaluation substrate obtained as described above was observed and evaluated.
⊚: Good developability without delamination or re-adhesion in exposed and unexposed areas under any conditions. Although workability such as control is inferior, there is no delamination and re-adhesion in the unexposed area.
x: Delamination and re-adhesion of the unexposed portion occurred when the breakpoint was 2/3 times (the film thickness was reduced to 2/3).
XX: Delamination and re-adhesion occurred when the breakpoint was halved (the film thickness was reduced to 1/2).

<Resolution evaluation>
Using a dry film having a resin layer thickness of about 15 μm prepared as described above, a plated copper substrate was treated with CZ-8201B at an etching rate of 0.5 μm / m ^2. Formation of the above resin layer. A resin layer composed of a curable resin composition was formed to have a film thickness of about 15 μm, and exposure was performed with various opening patterns using a Stouffer 41-step tablet so as to obtain 10 and 12 curing steps. Thereafter, development and curing were carried out according to the procedure for developing and curing the resin layer described above.
Observe the opening diameter of the evaluation substrate obtained as described above, and check whether it is possible to form a good opening diameter without the occurrence of halation or undercut under any of the 10-step and 12-step curing conditions using a Stouffer 41-step tablet. I checked and evaluated.
⊚: A good opening diameter is obtained at 50 μm ○: A good opening diameter is obtained at 60 μm ×: A good opening diameter is obtained at 70 μm, but a good opening diameter is not obtained at 60 μm or less XX …A satisfactory opening diameter cannot be obtained at 70 μm

<HAST resistance>
Using a dry film having a resin layer thickness of about 15 μm prepared as described above, a comb pattern of L/S = 8/8 μm was processed with CZ-8201B at an etching rate of 0.5 μm/m ^{2 .} A resin layer composed of a curable resin composition was formed on the formed substrate by the above resin layer formation/exposure procedure so as to have a film thickness of about 15 μm on copper, and the entire surface was exposed. Thereafter, development and curing were carried out according to the procedure for developing and curing the resin layer described above. After that, the electrodes were connected and a HAST test was performed under the conditions of 130° C., 85%, and 3.3 V.
◎: 300h pass
○: 250h pass, NG within 300h
△: 200h pass, NG within 250h
×: NG within 200 hours

<TCT resistance>
Using a dry film having a resin layer thickness of about 15 μm produced as described above, the above resin layer is formed on a package substrate that has been treated with CZ-8201B at an etching rate of 0.5 μm/m ^{2 .} - In the exposure procedure, a resin layer made of a curable resin composition was formed on Cu so as to have a film thickness of about 15 µm, and exposure was performed with an opening diameter of 80 µm on a copper pad with a pitch of 170 µm. Thereafter, development and curing were carried out according to the procedure for developing and curing the resin layer described above. After that, Au plating treatment, solder bump formation, and Si chip mounting were performed to obtain an evaluation substrate.
The evaluation substrate obtained above was placed in a thermal cycler in which temperature cycles were performed between −65° C. and 150° C., and a TCT (Thermal Cycle Test) was performed. Then, the surface of the cured film after 600 cycles, 800 cycles and 1000 cycles was observed. Judgment criteria are as follows.
◎: No abnormalities at 1000 cycles ○: No abnormalities at 800 cycles, cracks occurred at 1000 cycles △: No abnormalities at 600 cycles, cracks occurred at 800 cycles ×: Cracks occurred at 600 cycles

<Melt viscosity>
Using a dry film having a resin layer thickness of about 20 μm prepared as described above, the resin layer made of the curable resin composition was dried several times on a copper foil substrate so that the thickness of the resin layer was about 400 μm. The film was laminated.
The resin layer obtained above was peeled off from the copper foil and evaluated. The measurement was performed using a rheometer measuring device (manufactured by Hakke, model name: RS6000), and evaluation was performed at 40°C and 90°C. Evaluation criteria are as follows.
・・・40℃・・・
⊙: 8.0×10 ⁵ dPa·s or more ○: 1.0×10 ⁴ dPa·s or more and less than 8.0×10 ⁵ dPa·s ×: less than 1.0×10 ⁴ dPa·s: 90 ℃...
A: Less than 5.0×10 ¹ dPa·s ○: 5.0×10 ¹ dPa·s or more and less than 1.0×10 ³ dPa·s ×: 1.0×10 ³ dPa·s or more

*1: Carboxyl group-containing resin (A)-1 synthesized above
*2: Carboxyl group-containing resin (A)-2 synthesized above
*3: Carboxyl group-containing resin (A)-3 synthesized above
*4: Omnirad TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide) manufactured by IGM Resins
* 5: Omnirad 907 (2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one) manufactured by IGM Resins
* 6: BASF Japan Irgacure OXE02 (ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(o-acetyloxime)
* 7: Inorganic filler slurry (C) -1 prepared above
* 8: Inorganic filler slurry (C) -2 prepared above
* 9: Inorganic filler slurry (C) -3 prepared above
* 10: Inorganic filler slurry (C) -4 prepared above
*11: Inorganic filler slurry (C)-5 prepared above
* 12: Inorganic filler slurry (R) -1 prepared above
*13: Inorganic filler slurry (R)-2 prepared above
*14: Inorganic filler slurry (R)-3 prepared above
* 15: Inorganic filler slurry (R) -4 prepared above
* 16: Inorganic filler slurry (R) -5 prepared above
* 17: EPICLON N-770 manufactured by DIC (phenol novolac type epoxy resin, epoxy equivalent 185 g / eq.)
* 18: EPICLON N-740 manufactured by DIC (phenol novolak type epoxy resin, epoxy equivalent 180 g / eq.)
* 19: EPICLON N-730-A manufactured by DIC (phenol novolak type epoxy resin, epoxy equivalent 175 g / eq.)
* 20: Nippon Kayaku DPHA (dipentaerythritol hexaacrylate)
*21: Dicyandiamide

From the results shown in the above table, the curable resin compositions of Examples 1 to 12 of the present invention were excellent in developability without problems such as delamination in resolution and thin film formation, and excellent in HAST resistance and crack resistance. It turns out that hardened|cured material can be formed.

REFERENCE SIGNS LIST 1 substrate 2 conductor circuit 3 resin layer 3a made of curable resin composition resin layer 3b partially cured of curable resin composition resin layer 4 cured of curable resin composition first negative mask 5 second negative mask

Claims (7)

A curable resin composition containing a carboxyl group-containing resin, (B) a photopolymerization initiator, and (C) an inorganic filler,
A curable resin composition, wherein the particle size distribution of the inorganic filler (C) satisfies the following conditions (1) to (3).
(1) D50 particle size value = 1.0 µm or less (2) (D90 particle size value) / (D10 particle size value) = 5.0 or less (3) ((D90 particle size value) - (D50 particle size value) ) / ((D50 particle size value) - (D10 particle size value)) = 0.5 to 5.0 2. The curable resin composition according to claim 1, wherein the particle size distribution of the inorganic filler (C) further satisfies the following condition (4).
(4) D50 frequency = 7.0% or more 3. The curable resin composition according to claim 1, which is used in a method for producing a cured product comprising a step of partially thinning a resin layer comprising the curable resin composition with a developer. The curable resin according to any one of claims 1 to 3, wherein the content of the inorganic filler (C) is 25 to 70% by mass based on the total amount of the curable resin composition excluding the solvent. Composition. A dry film comprising a resin layer obtained by applying the curable resin composition according to any one of claims 1 to 4 on a film and drying the composition. A cured product obtained by curing the curable resin composition according to any one of claims 1 to 4 or the resin layer of the dry film according to claim 5. An electronic component comprising the cured product according to claim 6 .