CN111742014A

CN111742014A - Resin composition for laminated electronic component, dry film, cured product, laminated electronic component, and printed wiring board

Info

Publication number: CN111742014A
Application number: CN201880089860.3A
Authority: CN
Inventors: 兴津谕; 中条贵幸; 青山良朋; 远藤新; 管众
Original assignee: Taiyo Ink Mfg Co Ltd
Current assignee: Taiyo Holdings Co Ltd
Priority date: 2018-02-22
Filing date: 2018-12-27
Publication date: 2020-10-02
Also published as: JPWO2019163292A1; TW201936774A; WO2019163292A1; KR20200124700A; JP2020170172A

Abstract

Providing: a resin composition for laminated electronic components suitable for producing small-sized laminated electronic components excellent in visibility in appearance inspection, a dry film having a resin layer obtained from the composition, a cured product of the composition or the resin layer of the dry film, a laminated electronic component provided with a protective layer comprising the cured product, and a printed wiring board having the laminated electronic component. A resin composition for a laminated electronic component, which is used as a protective layer for a laminated electronic component in which electrode layers and insulating layers are alternately laminated and the protective layers are provided on both end surfaces in a laminating direction, is characterized by comprising: a curable resin, an inorganic filler, and a colorant.

Description

Resin composition for laminated electronic component, dry film, cured product, laminated electronic component, and printed wiring board

Technical Field

The present invention relates to a resin composition for laminated electronic components, a dry film, a cured product, a laminated electronic component, and a printed circuit board.

Background

With the recent trend toward higher precision and higher density of printed circuit boards due to the reduction in weight, size, and thickness of electronic devices, electronic components mounted on the printed circuit boards are also required to be miniaturized. One of the measures for downsizing electronic components is to realize a laminated structure, and in recent years, a process using an organic insulating layer has been proposed instead of a laminated ceramic technique. For example, patent document 1 describes an inductor manufactured by laminating an insulating layer made of an organic material and a layer made of a copper-plated electrode.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-225611

Disclosure of Invention

Problems to be solved by the invention

However, if electronic parts are miniaturized, it is difficult to find defective products by visual Inspection, and for example, even when Inspection is performed by an Automatic Optical Inspection Apparatus (AOI), defective products are missed, and there is a concern that the quality of products is adversely affected.

Accordingly, an object of the present invention is to solve the above problems, and to provide: a resin composition for laminated electronic components suitable for producing small-sized laminated electronic components excellent in visibility in appearance inspection, a dry film having a resin layer obtained from the composition, a cured product of the composition or the resin layer of the dry film, a laminated electronic component provided with a protective layer comprising the cured product, and a printed wiring board having the laminated electronic component.

Means for solving the problems

The present inventors have conducted intensive studies in view of the above, and as a result, have found that: the present invention has been accomplished to solve the above problems by providing protective layers containing an inorganic filler and a colorant on both end surfaces in the stacking direction of a small-sized laminated electronic component.

That is, the resin composition for a laminated electronic component according to the present invention is a resin composition used for a protective layer of a laminated electronic component in which electrode layers and insulating layers are alternately laminated and the protective layer is provided on both end surfaces in a laminating direction, the resin composition including: a curable resin, an inorganic filler, and a colorant.

In the resin composition for laminated electronic components of the present invention, it is preferable that the inorganic filler contains 2 or more kinds of inorganic fillers having different average particle diameters.

In the resin composition for a laminated electronic component of the present invention, the inorganic filler preferably contains silica.

In the resin composition for a laminated electronic component of the present invention, the colorant is preferably a white colorant.

In the resin composition for a laminated electronic component of the present invention, the white colorant is preferably titanium oxide.

In the resin composition for a laminated electronic component of the present invention, the amount of titanium oxide blended is preferably 10 mass% or less based on the total solid content of the composition.

The dry film of the present invention is characterized by comprising a resin layer obtained by applying the resin composition for laminated electronic components to a film and drying the resin composition.

The cured product of the present invention is obtained by curing the resin composition for laminated electronic components or the resin layer of the dry film.

The laminated electronic component of the present invention is characterized in that electrode layers and insulating layers are alternately laminated, and protective layers comprising the cured product are provided on both end surfaces in the laminating direction.

In the laminated electronic component of the present invention, the insulating layer is preferably formed from an alkali-developable resin composition containing an alkali-soluble resin, a photopolymerization initiator, and an inorganic filler.

The laminated electronic component of the present invention is preferably an inductor.

The printed circuit board of the present invention is characterized in that the laminated electronic component is mounted on at least one of the surface and the inside.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, there can be provided: a resin composition for laminated electronic components suitable for producing small-sized laminated electronic components excellent in visibility in appearance inspection, a dry film having a resin layer obtained from the composition, a cured product of the composition or the resin layer of the dry film, a laminated electronic component provided with a protective layer comprising the cured product, and a printed wiring board having the laminated electronic component.

Drawings

Fig. 1 is a schematic cross-sectional view schematically showing an embodiment of a laminated electronic component according to the present invention.

Detailed Description

The resin composition for a laminated electronic component of the present invention is a resin composition for a protective layer of a laminated electronic component in which electrode layers and insulating layers are alternately laminated and the protective layer is provided on both end surfaces in a laminating direction, the resin composition comprising: a curable resin, an inorganic filler, and a colorant. The inventors of the present invention found that: by providing the protective layers containing the coloring agent on both end surfaces in the lamination direction, the visibility in the direction of the laminated electronic component in the appearance inspection is greatly improved, and the missing of defective products can be reduced. Such improvement in visibility in the appearance inspection is particularly remarkable in a small-sized laminated electronic component having a side of less than 1 mm.

Further, if the electronic component is miniaturized, the handling thereof becomes difficult, and there is a concern that the electronic component may be damaged in the steps such as an inspection step, a component mounting step, and a transfer step.

According to the resin composition for a laminated electronic component of the present invention, since the protective layers containing the inorganic filler can be provided at both ends of the laminated electronic component in the laminating direction, the electrode layers and the insulating layers can be effectively protected, and the effect of improving the workability of the laminated electronic component can be exhibited. As described above, the resin composition for a laminated electronic component according to the present invention not only functions as a recognition layer of the laminated electronic component, but also functions to protect both the electrode layer and the insulating layer.

In the present invention, the colorant is preferably a white colorant, and is further excellent in visibility. Among these, titanium oxide is preferable, and particularly, titanium oxide is blended in an amount of 10 mass% or less based on the total solid content of the composition, so that the dielectric constant and the dielectric loss tangent can be reduced while maintaining the concealing property of the pattern of the electrode layer.

In addition, the resin composition for laminated electronic components of the present invention preferably contains a large amount of an inorganic filler from the viewpoint of improving the elastic modulus of the protective layer, and preferably contains 50 mass% or more of the inorganic filler relative to the total solid content of the composition. From the viewpoint of high filling and high elasticity of such an inorganic filler, it is preferable that the inorganic filler contains 2 or more inorganic fillers having different average particle diameters.

The curable resin constituting the resin composition for a laminated electronic component of the present invention may be either a thermosetting resin or a photocurable resin, or a mixture thereof. The components contained in the resin composition for laminated electronic components of the present invention will be described in detail below.

[ coloring agent ]

As the colorant, a commonly known colorant may be used, and any of a pigment, a dye, and a coloring matter may be used. Colorants such as green, yellow, red, black, blue, orange, violet, brown, white, etc., can be used, with white colorants being preferred. The colorant may be used in 1 kind or in combination of 2 or more kinds. Specifically, colorants are given The following color index (C.I.; issued by The Society of Dyers and Colourists) numbers. Among them, from the viewpoint of reducing environmental load and influence on the human body, it is more preferable that halogen is not contained.

Among the colorants, a white colorant, a blue colorant, and a black colorant are preferable, and a white colorant is more preferable, from the viewpoint of excellent visibility between the protective layer and the insulating layer of the inner layer of the laminated electronic component.

Examples of the white colorant include titanium oxide, zinc oxide, basic lead carbonate, basic lead sulfate, zinc sulfide, antimony oxide, and the like. The white colorant is preferably titanium oxide. By containing titanium oxide, the reflectance is increased, which is advantageous for improving the visibility, and the reflectance is also good after reflow soldering, so that the visibility in the appearance inspection can be maintained well.

As the rutile type titanium oxide, a known substance can be used. Specifically, there can be used TR-600, TR-700, TR-750, TR-840, R-550, R-580, R-630, R-820, CR-50, CR-58, CR-60, CR-90, CR-97, CR-953, KR-270, KR-310, KR-380, and the like, all available from Fuji titanium industries, Ltd.

The Y value of the cured product formed from the titanium oxide-containing composition is preferably 15 or more, more preferably 18 or more, and the upper limit of the Y value is preferably 45 or less.

From the viewpoint of visibility of the laminated electronic component in the visual inspection, the difference in reflectance between the protective layer and the insulating layer of the inner layer is preferably 10% or more, more preferably 20% or more, and still more preferably 40% or more at a wavelength of 450 nm. The inner layer is a layer formed between the outermost protective layers and used to form a circuit of the multilayer electronic component.

The coloring agent may be used alone or in combination of 2 or more. The amount of the colorant to be blended is preferably 10% by mass or less based on the total solid content of the composition.

When the white colorant is titanium oxide, it is preferably blended in an amount of 10 mass% or less based on the total solid content of the composition, as described above. More preferably 8% by mass or less, and still more preferably 5% by mass or less. On the other hand, the amount of titanium oxide blended is preferably 2% by mass or more.

[ inorganic Filler ]

By blending the inorganic filler, the physical strength and the like of the obtained cured product can be improved. The inorganic filler is advantageous in suppressing curing shrinkage of the protective layer, improving properties such as adhesion and hardness, and preventing peeling and scratching of the protective layer. As the inorganic filler, conventionally known inorganic fillers can be used, and examples thereof include, but are not limited to, specific ones: a bulk pigment such as barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, or spherical silica, talc, clay, nakeburg silica particles, boehmite, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, silicon nitride, aluminum nitride, or calcium zirconate, or a metal powder such as copper, tin, zinc, nickel, silver, palladium, aluminum, iron, cobalt, gold, or platinum. The inorganic filler is preferably spherical particles. Among these, silica is preferable, and suppresses curing shrinkage of the protective layer, resulting in a lower CTE, and also improving characteristics such as adhesion and hardness. The average particle diameter (median diameter, D50) of the inorganic filler is preferably 0.01 to 10 μm. In the present specification, the average particle diameter of the inorganic filler is an average particle diameter including not only the particle diameter of the primary particles but also the particle diameter of the secondary particles (aggregates). The average particle diameter can be determined by a laser diffraction particle size distribution measuring apparatus. Examples of the measuring apparatus by the laser diffraction method include a Nanotrac wave manufactured by Nikkiso K.K.

The aforementioned inorganic filler may be surface-treated. As the surface treatment, surface treatment without introducing an organic group such as surface treatment with a coupling agent, alumina treatment, or the like can be performed. The surface treatment method of the inorganic filler is not particularly limited, and a known and commonly used method can be employed, and the surface of the inorganic filler can be treated with a surface treatment agent having a curable reactive group, for example, a coupling agent having a curable reactive group as an organic group, or the like.

The surface treatment of the inorganic filler is preferably a surface treatment based on a coupling agent. As coupling agents, it is possible to use: silane-based, titanate-based, aluminate-based, and zircoaluminate-based coupling agents. Among them, silane coupling agents are preferable. Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminomethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane and the like, and they may be used alone or in combination. These silane coupling agents are preferably adsorbed on the surface of the inorganic filler in advance or immobilized by reaction. Here, the treatment amount of the coupling agent is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the inorganic filler.

Examples of the photocurable reactive group include ethylenically unsaturated groups such as a vinyl group, a styryl group, a methacryloyl group, and an acryloyl group. Among them, at least 1 kind of vinyl group and (meth) acryloyl group is preferable.

Examples of the thermosetting reactive group include a hydroxyl group, a carboxyl group, an isocyanate group, an amino group, an imino group, an epoxy group, an oxetanyl group, a mercapto group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, and an oxazoline group. Among them, at least 1 of an amino group and an epoxy group is preferable.

The inorganic filler subjected to surface treatment may be contained in the composition of the present invention in a state after surface treatment, and the inorganic filler and the surface treatment agent may be separately mixed, and the inorganic filler may be subjected to surface treatment in the composition, and preferably the inorganic filler subjected to surface treatment in advance is mixed. By blending the inorganic filler subjected to the surface treatment in advance, it is possible to prevent a reduction in crack resistance and the like due to the surface treatment agent that may remain in the respective blends and is not consumed in the surface treatment. When the surface treatment is performed in advance, it is preferable to blend a predispersion solution in which the inorganic filler is predispersed in a solvent or a curable resin, and more preferably to blend the predispersion solution in which the inorganic filler after the surface treatment is predispersed in a solvent into the composition, or to blend the predispersion solution in which the inorganic filler without the surface treatment is predispersed in a solvent into the composition after the surface treatment is sufficiently performed.

The inorganic filler may be blended with a curable resin or the like in a powder or solid state, or may be blended with a curable resin or the like after being mixed with a solvent or a dispersant to form a slurry.

The inorganic filler may be used alone in 1 kind, or may be used in the form of a mixture of 2 or more kinds. The amount of the inorganic filler is preferably 50 to 90% by mass, more preferably 60 to 90% by mass, and still more preferably 70 to 90% by mass, based on the total solid content of the composition.

When a mixture of 2 or more kinds is used as the inorganic filler, it is preferable to blend 2 kinds of inorganic fillers having different average particle diameters (hereinafter, (B-1) inorganic filler and (B-2) inorganic filler). The larger the difference between the average particle diameters of the (B-1) inorganic filler and the (B-2) inorganic filler, the better, and the average particle diameter of the (B-1) inorganic filler is preferably 5 times or more, more preferably 8 times or more, and still more preferably 10 times or more the average particle diameter of the (B-2) inorganic filler. The larger the difference is, the more the (B-2) inorganic filler can be filled in the gaps of the (B-1) inorganic filler, so that the remaining gaps can be reduced, and a resin composition having a small resin content, that is, a high ratio of the mass of the filler to the total mass can be obtained. In the above case, it is more effective to include 50% by mass or more of the total mass of the solid components of the composition, and it is effective to include 60% by mass or more and 70% by mass or more. By increasing the mass ratio of the inorganic filler in the total mass of the solid components of the composition, a cured product having excellent strength, a high energy storage modulus, and a low coefficient of linear expansion (CTE) can be formed. In the case of a dry film, the lamination properties of the counter electrode layer and the insulating layer are also excellent.

The average particle diameter of the inorganic filler (B-1) is preferably 5 μm or less. The maximum particle diameter of the (B-2) inorganic filler is preferably 500nm or less.

The blending ratio of the (B-1) and (B-2) inorganic fillers is preferably (B-1): (B-2) ═ 5: 5-12: 1. further preferably 3: 1-8: 1. when the amount is within the above range, the strength of the cured product and the laminatability of the dry film can be further improved.

The presence or absence of the surface treatment of the (B-1) and (B-2) inorganic fillers is not particularly limited. However, as described above, the curable composition of the present invention has a small resin content, and therefore, the inorganic fillers (B-1) and (B-2) are preferably subjected to a surface treatment for improving dispersibility.

[ curable resin ]

The curable resin composition of the present invention contains a curable resin. The curable resin used in the present invention may be any of a thermosetting resin and a photocurable resin, or may be a mixture thereof.

(thermosetting resin)

The thermosetting resin is a resin having a functional group capable of undergoing a thermal curing reaction. The thermosetting resin is not particularly limited, and the following resins can be used: epoxy compounds, oxetane compounds, compounds having 2 or more sulfide groups in the molecule, namely, episulfide resins, melamine resins, benzoguanamine resins, melamine derivatives, benzoguanamine derivatives and other amino resins, blocked isocyanate compounds, cyclic carbonate compounds, bismaleimides, carbodiimides and the like.

The epoxy compound is a compound having an epoxy group, and conventionally known epoxy compounds can be used, and examples thereof include a 2-functional epoxy compound having 2 epoxy groups in the molecule, and a polyfunctional epoxy compound having a plurality of epoxy groups in the molecule. The epoxy compound may be a hydrogenated 2-functional epoxy compound.

As epoxy compounds, for example, there may be used: bisphenol a type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol a type epoxy resin, brominated bisphenol a type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol a novolac type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phosphorus-containing epoxy resin, anthracene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, aminophenol type epoxy resin, alkylphenol type epoxy resin, and the like. These epoxy resins may be used alone in 1 kind, or in combination of 2 or more kinds.

The epoxy compound may be any of a solid epoxy resin, a semi-solid epoxy resin, and a liquid epoxy resin. In the present specification, a solid epoxy resin means an epoxy resin that is solid at 40 ℃, a semisolid epoxy resin means an epoxy resin that is solid at 20 ℃ and liquid at 40 ℃, and a liquid epoxy resin means an epoxy resin that is liquid at 20 ℃. The determination of the liquid state may be performed according to "method for confirming liquid state" attached to province of labor and property of dangerous objects (No. 1 of the "annual self-governing province" in the average). For example, the method described in paragraphs 23 to 25 of Japanese patent application laid-open No. 2016-079384 can be used.

Examples of the solid epoxy resin include: naphthalene type epoxy resins such as HP-4700 (naphthalene type epoxy resin) manufactured by DIC corporation, EXA4700 (4-functional naphthalene type epoxy resin) manufactured by DIC corporation, and NC-7000 (naphthalene skeleton-containing polyfunctional solid epoxy resin) manufactured by Nippon Kabushiki Kaisha; an epoxide (trisphenol type epoxy resin) of a condensate of a phenol such as EPPN-502H (trisphenol epoxy resin) manufactured by Nippon Kagaku K.K. and an aromatic aldehyde having a phenolic hydroxyl group; dicyclopentadiene aralkyl type epoxy resins such as Epiclon HP-7200H (a multifunctional solid epoxy resin having a dicyclopentadiene skeleton) manufactured by DIC; biphenyl aralkyl type epoxy resins such as NC-3000H (multifunctional solid epoxy resin having a biphenyl skeleton) manufactured by Nippon Chemicals corporation; biphenyl/phenol novolac type epoxy resins such as NC-3000L manufactured by Nippon Chemicals; novolak type epoxy resins such as Epiclon N660 and Epiclon N690 manufactured by DIC corporation and EOCN-104S manufactured by Nippon chemical Co., Ltd.; biphenyl type epoxy resins such as YX-4000 manufactured by Mitsubishi Chemical Corporation; phosphorus-containing epoxy resins such as TX0712 manufactured by Nissin iron-on-gold chemical Co., Ltd; tris (2, 3-epoxypropyl) isocyanurate such as TEPIC manufactured by Nissan chemical industries, Ltd.

Examples of the semisolid epoxy resin include bisphenol A type epoxy resins such as Epiclon 860, Epiclon900-IM, Epiclon EXA-4816, Epiclon EXA-4822, Araldite AER280 manufactured by Asahi-Ciba Limited, EPOTETE YD-134 manufactured by Tokyo Chemical Co., Ltd, Jer834 and Jer872 manufactured by Mitsubishi Chemical Corporation, and ELA-134 manufactured by Sumitomo Chemical industry Co., Ltd; naphthalene epoxy resins such as Epiclon HP-4032 manufactured by DIC; and phenol novolac epoxy resins such as Epiclon N-740 manufactured by DIC.

Examples of the liquid epoxy resin include bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol AF type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, glycidylamine type epoxy resin, aminophenol type epoxy resin, and alicyclic epoxy resin.

Next, examples of the oxetane compound 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, polyfunctional oxetanes such as (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate, and oligomers or copolymers thereof; and etherates of oxetane and a hydroxyl group-containing resin such as novolak resin, poly (p-hydroxystyrene), Cardo-type bisphenol, calixarene resorcinol, or silsesquioxane. Further, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate, and the like can be mentioned. In the present specification, the term (meth) acrylate refers to a general term of acrylate, methacrylate and a mixture thereof, and the same applies to other similar expressions.

Examples of the episulfide resin include bisphenol a type episulfide resins. In addition, it is also possible to use: and cyclic thioether resins obtained by substituting an oxygen atom of an epoxy group of an epoxy resin with a sulfur atom by the same synthesis method.

In the present invention, an epoxy compound is preferably used as the thermosetting resin. Among them, in order to increase the elastic modulus, a solid epoxy resin is preferably contained. In order to maintain the flexibility of the dry film of the resin composition, it is more preferable to use a semisolid epoxy resin and a liquid epoxy resin in combination.

The thermosetting resin may be used alone in 1 kind or in combination of 2 or more kinds. The amount of the thermosetting resin blended is preferably 5 to 40%, more preferably 10 to 30%, and still more preferably 15 to 20% based on the total amount of the solid components in the composition.

(Photocurable resin)

The photocurable resin may be a resin that is cured by irradiation with an active energy ray and exhibits electrical insulation, and a compound having 1 or more ethylenically unsaturated bonds in the molecule is preferably used. The photocurable resin may be used alone in 1 kind or in combination with 2 or more kinds.

As the compound having an ethylenically unsaturated bond, a known and commonly used photopolymerizable oligomer, a photopolymerizable vinyl monomer, or the like can be used. Among these, examples of the photopolymerizable oligomer include unsaturated polyester oligomers and (meth) acrylate oligomers. Examples of the (meth) acrylate-based oligomer include epoxy (meth) acrylates such as phenol novolac epoxy (meth) acrylate, cresol novolac epoxy (meth) acrylate, bisphenol epoxy (meth) acrylate, urethane (meth) acrylate, epoxy urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, and polybutadiene-modified (meth) acrylate.

Examples of the photopolymerizable vinyl monomer include: known and commonly used substances include, for example, styrene derivatives such as styrene, chlorostyrene and α -methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate, and vinyl benzoate; vinyl ethers such as vinyl isobutyl ether, vinyl-n-butyl ether, vinyl-tert-butyl ether, vinyl-n-pentyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinyl cyclohexyl ether, ethylene glycol monobutyl vinyl ether, and triethylene glycol monomethyl vinyl ether; (meth) acrylamides such as acrylamide, methacrylamide, N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymmethacrylamide, N-ethoxymethacrylamide and N-butoxymethacrylamide; allyl compounds such as triallyl isocyanurate, diallyl phthalate, and diallyl isophthalate; esters of (meth) acrylic acid such as 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, and the like; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and pentaerythritol tri (meth) acrylate; alkoxyalkylene glycol mono (meth) acrylates such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; alkylene polyol poly (meth) acrylates such as ethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like; polyoxyalkylene glycol poly (meth) acrylates such as diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane tri (meth) acrylate; poly (meth) acrylates such as neopentyl glycol hydroxy-tert-valerate di (meth) acrylate; and isocyanurate type poly (meth) acrylates such as tris [ (meth) acryloyloxyethyl ] isocyanurate.

When the resin composition of the present invention is an alkali-developable photosensitive resin composition, a carboxyl group-containing resin is preferably used as the curable resin. The carboxyl group-containing resin may be a carboxyl group-containing photosensitive resin having an ethylenically unsaturated group, and may or may not have an aromatic ring. As the carboxyl group-containing resin, a resin using an epoxy resin as a starting material, a resin using a phenol compound as a starting material, a resin having a urethane structure, a resin having a copolymerized structure, and a resin having an imide structure are preferable. As the curable resin, a resin containing a phenolic hydroxyl group can be used.

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

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

(2) The carboxyl group-containing polyurethane resin is obtained by addition polymerization of a diisocyanate such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate or an aromatic diisocyanate, a carboxyl group-containing diol compound such as dimethylolpropionic acid or dimethylolbutyric acid, and a diol compound such as a polycarbonate-based polyol, a polyether-based polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic polyol, a bisphenol A-based alkylene oxide adduct diol, or a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(3) The polyurethane resin is a carboxyl-terminated polyurethane resin obtained by addition polymerization of a diisocyanate compound such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate, or an aromatic diisocyanate with a diol compound such as a polycarbonate polyol, a polyether polyol, a polyester polyol, a polyolefin polyol, an acrylic polyol, a bisphenol a alkylene oxide adduct diol, or a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(4) The photosensitive carboxyl group-containing polyurethane resin is obtained by addition polymerization of a diisocyanate and a (meth) acrylate of a 2-functional epoxy resin such as a bisphenol A epoxy resin, a hydrogenated bisphenol A epoxy resin, a bisphenol F epoxy resin, a bisphenol S epoxy resin, a bixylenol epoxy resin, a bidiphenol epoxy resin, or a partial acid anhydride modification thereof, a carboxyl group-containing diol compound, and a diol compound.

(5) In the synthesis of the resin of the above (2) or (4), a carboxyl group-containing urethane resin having a terminal (meth) acryloyl group, which is a compound having 1 hydroxyl group and 1 or more (meth) acryloyl groups in the molecule, such as hydroxyalkyl (meth) acrylate, is added.

(6) In the synthesis of the resin of the above (2) or (4), a compound having 1 isocyanate group and 1 or more (meth) acryloyl groups in the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, and a carboxyl group-containing urethane resin having a terminal (meth) acryloyl group are added.

(7) A photosensitive carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with (meth) acrylic acid to add a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride or hexahydrophthalic anhydride to a hydroxyl group present in a side chain.

(8) The photosensitive carboxyl group-containing resin is obtained by further epoxidizing the hydroxyl group of a 2-functional epoxy resin with epichlorohydrin to obtain a polyfunctional epoxy resin, reacting the obtained polyfunctional epoxy resin with (meth) acrylic acid, and adding a dibasic acid anhydride to the generated hydroxyl group.

(9) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid and adding a dibasic acid anhydride to the primary hydroxyl group thus produced.

(10) A carboxyl group-containing photosensitive resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in 1 molecule with an alkylene oxide such as ethylene oxide or propylene oxide to obtain a reaction product, reacting the obtained reaction product with an unsaturated group-containing monocarboxylic acid, and reacting the obtained reaction product with a polybasic acid anhydride.

(11) A carboxyl group-containing photosensitive resin obtained by reacting a compound having a plurality of phenolic hydroxyl groups in 1 molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate to obtain a reaction product, reacting the obtained reaction product with an unsaturated group-containing monocarboxylic acid, and reacting the obtained reaction product with a polybasic acid anhydride.

(12) A carboxyl group-containing photosensitive resin obtained by reacting an epoxy compound having a plurality of epoxy groups in 1 molecule with a compound having at least 1 alcoholic hydroxyl group and 1 phenolic hydroxyl group in 1 molecule such as p-hydroxyphenylethanol, and an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid, and reacting a polybasic acid anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, or adipic acid with respect to the alcoholic hydroxyl group of the obtained reaction product.

(13) A photosensitive carboxyl group-containing resin obtained by further adding a compound having 1 epoxy group and 1 or more (meth) acryloyl groups in the molecule, such as glycidyl (meth) acrylate or α -methylglycidyl (meth) acrylate, to any of the resins (1) to (12).

The carboxyl group-containing resin described above has a large number of carboxyl groups in the main chain and the side chain of the polymer, and therefore, can be developed with a dilute aqueous alkali solution.

The acid value of the carboxyl group-containing resin is preferably in the range of 20 to 2000mgKOH/g, more preferably in the range of 40 to 1800 mgKOH/g. When the content is in the range of 20 to 2000mgKOH/g, the adhesiveness of the coating film can be obtained, the alkali development is easy, the dissolution of the exposed portion by the developer is suppressed, and the drawing of a normal resist pattern is easy without making the lines thinner than necessary, which is preferable.

The weight average molecular weight of the carboxyl group-containing resin used in the present invention varies depending on the resin skeleton, and is preferably in the range of 2000 to 150000. When the amount is in this range, the tack free property is good, the moisture resistance of the coating film after exposure is good, and the film loss is less likely to occur during development. In addition, if the weight average molecular weight is within the above range, the resolution is improved, the developability is good, and the storage stability is good. More preferably 5000 to 100000. The weight average molecular weight can be determined by gel permeation chromatography.

(curing agent)

When the resin composition of the present invention contains a thermosetting resin, it preferably contains a curing agent. Examples of the curing agent include: a compound having a phenolic hydroxyl group, a polycarboxylic acid and an acid anhydride thereof, a compound having a cyanate group, a compound having an active ester group, a compound having a maleimide group, an alicyclic olefin polymer, and the like. The curing agent can be used alone in 1 kind, or in combination of 2 or more kinds. Here, the dielectric loss tangent after humidification can be reduced by using a compound having at least a cyanate ester group or a compound having an active ester group. Further, by using a compound having at least a cyanate group or a compound having a maleimide group, the crack resistance during a cold-heat cycle after reflow soldering is improved.

As the compound having a phenolic hydroxyl group, there can be used: conventionally known phenol novolac resins, such as phenol novolac resins, alkylphenol novolac resins, bisphenol a novolac resins, dicyclopentadiene type phenol resins, Xylok type phenol resins, terpene modified phenol resins, cresol/naphthol resins, polyvinyl phenols, phenol/naphthol resins, phenol resins having an α -naphthol skeleton, cresol novolac resins having a triazine skeleton, biphenyl aralkyl type phenol resins, and Xylok type phenol novolac resins.

Among the compounds having a phenolic hydroxyl group, those having a hydroxyl group equivalent of 100g/eq or more are preferred. Examples of the compound having a phenolic hydroxyl group with a hydroxyl group equivalent of 100g/eq. or more include: dicyclopentadiene skeleton phenol novolak resin (GDP series, available from Kyoho chemical Co., Ltd.), xylok type phenol novolak resin (MEH-7800, available from Minghua chemical Co., Ltd.), biphenyl aralkyl type novolak resin (MEH-7851, available from Minghua chemical Co., Ltd.), naphthol aralkyl type curing agent (SN series, available from Xinri Tokken chemical Co., Ltd.), and cresol novolak resin having a triazine skeleton (LA-3018-50P, DIC Co., Ltd.), and the like.

The compound having an isocyanate group is a compound having 2 or more isocyanate groups (-OCN) in one molecule. Any conventionally known compound having a cyanate group can be used. Examples of the compound having a cyanate group include phenol novolac type cyanate ester resins, alkylphenol novolac type cyanate ester resins, dicyclopentadiene type cyanate ester resins, bisphenol a type cyanate ester resins, bisphenol F type cyanate ester resins, and bisphenol S type cyanate ester resins. In addition, a prepolymer in which a part of the prepolymer is triazinized may be used.

The compound having an active ester group is a compound having 2 or more active ester groups in one molecule. The compound having an active ester group can be usually obtained by a condensation reaction of a carboxylic acid compound and a hydroxyl compound. Among them, compounds having an active ester group obtained by using a phenol compound or a naphthol compound as a hydroxyl compound are preferable. Examples of the phenol compound or naphthol compound include hydroquinone, resorcinol, bisphenol a, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol a, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α -naphthol, β -naphthol, 1, 5-dihydroxynaphthalene, 1, 6-dihydroxynaphthalene, 2, 6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadienyl diphenol, phenol novolak and the like. The compound having an active ester group may be a naphthalene diol alkyl/benzoic acid type.

The compound having a maleimide group is a compound having a maleimide skeleton, and any one of conventionally known compounds can be used. The compound having a maleimide group preferably has 2 or more maleimide skeletons, more preferably N, N ' -1, 3-phenylenedimaleimide, N ' -1, 4-phenylenedimaleimide, N ' -4, 4-diphenylmethane bismaleimide, 1, 2-bis (maleimide) ethane, 1, 6-bismaleimide hexane, 1, 6-bismaleimide- (2,2, 4-trimethyl) hexane, 2 ' -bis- [4- (4-maleimidophenoxy) phenyl ] propane, 3 ' -dimethyl-5, 5 ' -diethyl-4, 4 ' -diphenylmethane bismaleimide, 4-methyl-1, at least 1 kind of 3-phenylene bismaleimide, bis (3-ethyl-5-methyl-4-maleimide phenyl) methane, bisphenol A diphenyl ether bismaleimide, polyphenyl methane maleimide, and their oligomer, and diamine condensate with maleimide skeleton. The oligomer is obtained by condensing a compound having a maleimide group, which is a monomer of the compound having a maleimide group.

The amount of the curing agent is preferably 2 to 30%, more preferably 3 to 20%, and still more preferably 3 to 10% based on the total solid content of the composition.

The curing agent is preferably compounded in such a ratio that the ratio of a functional group capable of undergoing a thermosetting reaction, such as an epoxy group, of the thermosetting resin to a functional group in the curing agent reactive with the functional group is 0.2 to 2, i.e., the ratio of the functional group of the curing agent to the functional group capable of undergoing a thermosetting reaction (equivalent ratio). When the ratio of the functional group of the curing agent to the functional group capable of undergoing a thermosetting reaction (equivalent ratio) is in the above range, the water absorption rate and the dielectric loss tangent of the resin composition of the protective layer can be prevented from increasing. More preferably, the ratio of the functional group of the curing agent to the functional group capable of undergoing a thermosetting reaction (equivalent ratio) is 0.3 to 1.0.

[ curing accelerators ]

When a thermosetting resin is used in the resin composition of the present invention, a curing accelerator may be blended together with the curing agent or may be blended alone. The curing accelerator is used for accelerating a thermosetting reaction and is used for further improving properties such as adhesion, chemical resistance, and heat resistance. Specific examples of such a curing accelerator include: imidazole and derivatives thereof; guanamines such as methylguanamine and benzoguanamine; polyamines such as diaminodiphenylmethane, m-phenylenediamine, m-xylylenediamine, diaminodiphenylsulfone, dicyandiamide, urea derivatives, melamine, and polyhydrazide; organic acid salts and/or epoxy adducts thereof; an amine complex of boron trifluoride; triazine derivatives such as ethyldiamino-s-triazine, 2, 4-diamino-s-triazine, and 2, 4-diamino-6-xylyl-s-triazine; amines such as trimethylamine, triethanolamine, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4, 6-tris (dimethylaminophenol), tetramethylguanidine, and m-aminophenol; polyphenols such as polyvinyl phenol, polyvinyl phenol bromide, phenol novolac, and alkylphenol novolac; organic phosphines such as tributylphosphine, triphenylphosphine, and tris-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl (2, 5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosphonium chloride; quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; the foregoing polybasic acid anhydrides; photocationic polymerization catalysts such as diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, 2,4, 6-triphenylthiopyrylium hexafluorophosphate and the like; styrene-maleic anhydride resin; an equimolar reaction product of phenyl isocyanate and dimethylamine, an equimolar reaction product of an organic polyisocyanate such as toluene diisocyanate or isophorone diisocyanate and dimethylamine, a conventionally known curing accelerator such as a metal catalyst. Among the curing accelerators, phosphonium salts are preferable in terms of obtaining the resistance to BHAST. The curing accelerator may be used alone in 1 kind, or in a mixture of 2 or more kinds.

The curing accelerator is not essential, and can be used in the range of preferably 0.01 to 5 parts by mass, more preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the thermosetting resin, particularly when it is desired to accelerate curing. In addition, in the case of the metal catalyst, the amount is preferably 10 to 550ppm, more preferably 25 to 200ppm in terms of metal, based on 100 parts by mass of the thermosetting resin.

[ photopolymerization initiator ]

When a photocurable resin is used in the resin composition of the present invention, a photopolymerization initiator is preferably further compounded. Any photopolymerization initiator can be used as long as it is known as a photopolymerization initiator or a photoradical generator.

Examples of the photopolymerization initiator include: 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, bisacylphosphine oxides such as bis- (2, 6-dimethoxybenzoyl) phenylphosphine oxide, bis- (2, 6-dimethoxybenzoyl) -2,4, 4-trimethylpentylphosphine oxide, bis- (2, 6-dimethoxybenzoyl) -2, 5-dimethylphenylphosphine oxide, and bis- (2,4, 6-trimethylbenzoyl) -phenylphosphine oxide; monoacyl phosphine oxides such as 2, 6-dimethoxybenzoyldiphenylphosphine oxide, 2, 6-dichlorobenzoyldiphenylphosphine oxide, methyl 2,4, 6-trimethylbenzoylphenylphosphinate, 2-methylbenzoyldiphenylphosphine oxide, isopropyl pivaloylphenylphosphine oxide and 2,4, 6-trimethylbenzoyldiphenylphosphine oxide; hydroxyacetophenones such as 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-propan-1-one, and 2-hydroxy-2-methyl-1-phenylpropan-1-one; benzoins such as benzoin, benzoyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, and benzoin-butyl ether; benzoin alkyl ethers; benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4 ' -dichlorobenzophenone, and 4,4 ' -bisdiethylaminobenzophenone; acetophenone, 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-2-phenylacetophenone, 1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone (manufactured by BASF Japan K.K., acetophenones such as IRGACURE369), 2- (dimethylamino) -2- [ (4-methylphenyl) methyl) -1- [4- (4-morpholinyl) phenyl ] -1-butanone, and N, N-dimethylaminoacetophenone; thioxanthones such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2, 4-dimethylthioxanthone, 2, 4-diethylthioxanthone, 2-chlorothioxanthone and 2, 4-diisopropylthioxanthone; anthraquinones such as anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, and 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal and benzil dimethyl ketal; benzoic acid esters such as ethyl-4-dimethylaminobenzoate, 2- (dimethylamino) ethylbenzoate, and ethyl p-dimethylbenzoate; oxime esters such as {1- [4- (phenylthio) -2- (O-benzoyloxime) ] }1, 2-octanedione, 1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone-1- (O-acetyloxime), and the like; titanocenes such as bis (. eta.5-2, 4-cyclopentadien-1-yl) -bis (2, 6-difluoro-3- (1H-pyrrol-1-yl) phenyl) titanium, bis (cyclopentadienyl) -bis [2, 6-difluoro-3- (2- (1-pyrrol-1-yl) ethyl) phenyl ] titanium, and the like; phenyl disulfide 2-nitrofluorene, butyroin, anisoin ethyl ether, azobisisobutyronitrile, tetramethylthiuram disulfide, and the like. The photopolymerization initiator may be used alone, or 2 or more kinds may be used in combination.

The amount of the photopolymerization initiator is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 25 parts by mass, in terms of solid content, per 100 parts by mass of the photocurable resin. By blending the photopolymerization initiator in this range, photocurability on copper becomes sufficient, curability of the coating film becomes good, coating film characteristics such as chemical resistance are improved, and deep curing properties are also improved.

[ thermoplastic resin ]

The resin composition of the present invention may further contain a thermoplastic resin in order to improve the mechanical strength of the obtained cured film. The thermoplastic resin is preferably soluble in a solvent. When the resin is soluble in a solvent, the flexibility of the dry film is improved, and the occurrence of cracks and dusting can be suppressed. Examples of the thermoplastic resin include thermoplastic polyhydroxypolyether resins, phenoxy resins which are condensates of epichlorohydrin and various 2-functional phenol compounds, phenoxy resins obtained by esterifying the hydroxyl group of the hydroxyether moiety present in the skeleton thereof with various acid anhydrides or acid chlorides, polyvinyl acetal resins, polyamide resins, polyamideimide resins, block copolymers, and the like. The thermoplastic resin may be used alone, or 2 or more kinds may be used in combination.

The amount of the thermoplastic resin is preferably 1 to 10%, more preferably 1 to 5%, and still more preferably 1.5 to 5% based on the total solid content of the composition. By setting the amount of the thermoplastic resin in the above range, the flexibility of the dry film and the mechanical strength of the protective layer can be improved while maintaining a high glass transition temperature (Tg).

[ rubber-like particles ]

Further, the resin composition of the present invention may contain rubber-like particles as needed. Examples of such rubber-like particles include polybutadiene rubber, polyisopropylene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl-modified polybutadiene rubber, acrylonitrile-butadiene rubber modified with a carboxyl group or a hydroxyl group, and crosslinked rubber particles and core-shell rubber particles thereof, and 1 type of such rubber-like particles can be used alone or 2 or more types can be used in combination. These rubber-like particles are added for the purpose of improving the flexibility of the resulting cured film or improving the crack resistance.

The average particle diameter of the rubber-like particles is preferably in the range of 0.005 to 1 μm, more preferably in the range of 0.2 to 1 μm. The average particle diameter of the rubber-like particles in the present invention can be determined by a laser diffraction type particle diameter distribution measuring apparatus. For example, the following can be measured: the rubber-like particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves or the like, and the particle size distribution of the rubber-like particles is prepared on a mass basis by a Nanotrac wave manufactured by Nikkiso K.K., and the median particle size is determined as an average particle size.

The amount of the rubber-like particles to be blended is preferably 1 to 10%, more preferably 1 to 5%, based on the total solid content of the composition. By setting the amount within the above range, the flexibility and crack resistance of the cured film can be improved while maintaining a high glass transition temperature (Tg).

[ organic solvent ]

The organic solvent is not particularly limited, and examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. More specifically, there may be mentioned: ketones such as methyl ethyl ketone, cyclohexanone, methyl butyl ketone, and methyl isobutyl ketone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, 2-methoxypropanol, n-butanol, isobutanol, isoamyl alcohol, 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; and N, N-Dimethylformamide (DMF), tetrachloroethylene, turpentine, and the like. Further, organic solvents such as Swazol 1000, Swazol 1500, Solvesso 100 manufactured by Standard OilOsaka Development Company, Solvesso 150, Solvent #100 manufactured by Sanko Co., Ltd., Solvent #150, Shellsol A100 manufactured by Shell chemicals Japan Limited, Shellsol A150, Ipzol No. 100 manufactured by Kashinghover corporation, Ipzol No. 150 and the like may be used. The organic solvent may be used alone in 1 kind, or may be used in the form of a mixture of 2 or more kinds.

[ other ingredients ]

The resin composition of the present invention may further contain other conventionally known additives as needed. Examples of the other additives include conventionally known thickeners such as asbestos, Orben, Benton, and fine silica, defoaming agents and/or leveling agents such as silicone-based, fluorine-based, and polymer-based additives, adhesion improving agents such as thiazole-based, triazole-based, and silane coupling agents, fine powders such as cellulose nanofibers, antioxidants such as hindered phenol-based additives, flame retardants, titanate-based, and aluminum-based additives.

The resin composition of the present invention may be used in the form of a dry film or in the form of a liquid. When the liquid is used in a liquid state, the liquid may be 1 liquid or 2 liquid or more.

The dry film of the present invention can be produced as follows: the resin composition of the present invention is applied to a carrier film and dried to form a resin layer. A protective film may be attached to the resin layer as needed.

The carrier film is a film having a function of supporting the resin layer of the dry film, and is a thin film coated with the resin composition when the resin layer is formed. As the carrier film, for example, it is possible to suitably use: polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyimide films, polyamideimide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, polystyrene films and the like, films made of thermoplastic resins, surface-treated papers and the like, among which polyester films can be suitably used from the viewpoint of heat resistance, mechanical strength, handling properties and the like. The thickness of the carrier film is not particularly limited, and may be appropriately selected within a range of approximately 10 to 150 μm depending on the application. The surface of the carrier film on which the resin layer is provided may be subjected to a release treatment.

The protective film is provided on the surface of the resin layer opposite to the carrier film for the purpose of preventing adhesion of dust or the like to the surface of the resin layer of the dry film and improving workability. As the protective film, for example, a film made of a thermoplastic resin, a surface-treated paper, or the like as exemplified in the carrier film can be used, and among them, a polyester film, a polyethylene film, and a polypropylene film are preferable. The thickness of the protective film is not particularly limited, and may be appropriately selected within a range of approximately 10 to 150 μm depending on the application. The surface of the protective film on which the resin layer is provided may be subjected to a mold release treatment.

The amount of the residual solvent in the resin layer is preferably 0.1 to 5.0% by mass, more preferably 0.1 to 3.0% by mass, and still more preferably 0.5 to 2.0% by mass. When the residual solvent content is 5.0% by mass or less, bumping during thermal curing is suppressed, and the surface flatness is improved. Further, the flow of the resin due to an excessive decrease in melt viscosity can be suppressed, and the flatness can be improved. When the residual solvent content is 0.1% by mass or more, the fluidity at the time of lamination is good, and the flatness and embeddability become better. In addition, if the residual solvent is 0.5-2.0 mass%, the dry film operability and coating film characteristics are excellent.

Here, as a method of coating the resin composition, there can be used: dip coating, flow coating, roll coating, bar coating, screen printing, curtain coating, and the like. As the evaporation drying method, an evaporation drying method using a heat source of an air heating system using steam, such as a hot air circulation drying oven, an IR (infrared) oven, a hot plate, or a convection oven, can be used.

When a liquid curable resin composition is used as a method for forming a protective layer of a laminated electronic component using the resin composition of the present invention, the liquid curable resin composition may be applied by a method such as roll coating, bar coating, screen printing, curtain coating, and the like, and then temporarily dried at a low temperature of 50 to 100 ℃ for 20 to 60 minutes to evaporate the solvent, and then thermally cured at a temperature of 150 to 250 ℃ for 30 to 90 minutes. When the resin composition is used as a dry film, a protective layer can be formed by laminating dry films by a lamination method, a pressure method, or the like, and then thermally curing the laminated dry films at a temperature of 150 to 250 ℃ for 30 to 90 minutes.

The laminated electronic component of the present invention is characterized in that electrode layers and insulating layers are alternately laminated, and protective layers comprising a cured product of the composition of the present invention are provided on both end surfaces in the laminating direction. The laminated electronic component of the present invention is useful for laminated electronic components used in various electronic devices such as digital devices, AV devices, and information communication terminals. The laminated electronic component of the present invention is a passive component such as an inductor, or an active component. The laminated electronic component is preferably an inductor.

Fig. 1 schematically shows a schematic cross-sectional view of an embodiment of the laminated electronic component according to the present invention, but the present invention is not limited thereto. In fig. 1, the external electrodes 15a and 15b are connected to an inductor as the laminated electronic component 11. The electrode layers 12a to 12f and the insulating layers 13a to 13f are alternately laminated, and protective layers 14a and 14b are provided on both end surfaces in the laminating direction. The electrode layers 12a to 12f are formed in a coil shape as a whole.

The size of the laminated electronic component of the present invention is not particularly limited, and one side may be 1mm or less, and each side may be 1mm or less, and further each side may be 500 μm or less, and further each side may be 200 μm or less, and the visibility in the appearance inspection is also excellent.

The protective layer is a cured product of the laminated electronic component composition of the present invention. The thickness of the protective layer is preferably 100 μm or less, more preferably 50 μm or less, and still more preferably 30 μm or less. The protective layer preferably has a coefficient of thermal expansion (CTE (. alpha.1)) of less than 25ppm, and a storage modulus (E') of preferably 15GPa or more, more preferably 16GPa or more.

The electrode layer preferably has a thickness of 50 μm or less, more preferably 15 μm or less. The electrode layer is not particularly limited as long as it is made of a material having conductivity, such as a silver (Ag) material or a copper (Cu) material, and a circuit formed of copper is particularly preferably used. In addition, in the case of paste such as copper paste and silver paste, there may be mentioned a method of forming by screen printing or the like, and further, a method of forming by etching copper foil, copper plating, coil lead wire or the like, and in one embodiment of the present invention, any method may be adopted, and there is no particular limitation.

The insulating layer may be an organic insulating layer, and may be an insulating layer formed from a cured product of a thermosetting resin composition, an insulating layer formed from a photocurable resin composition, or an insulating layer formed from a photocurable and thermosetting resin composition. As the organic insulating layer, a cured film of a conventional printed wiring board, for example, a cured product of a curable resin composition for forming a solder resist layer or the like can be used. The insulating layer is preferably 50 μm or less, more preferably 30 μm or less, and still more preferably 20 μm or less. When a liquid resin composition is used for the insulating layer, a roll coating method, a bar coating method, a screen printing method, a curtain coating method, or the like can be used. When used as a dry film, a lamination method, a pressure method, or the like can be used.

Here, when the insulating layer is obtained by curing an alkali-developable resin composition containing an alkali-soluble resin, a photopolymerization initiator, and an inorganic filler, depending on the amount of the inorganic filler blended (for example, 20 to 70 mass% based on the total solid content of the composition), the storage modulus of the insulating layer may be lowered, and the strength of the entire laminated electronic component may be lowered. However, by forming protective layers obtained by curing the resin composition of the present invention on both end surfaces of the laminated electronic component, the strength of the entire laminated electronic component can be ensured. In the above case, the resin composition of the present invention can exhibit the above-described effects in a favorable manner when the amount of the inorganic filler is 50 to 90 mass% based on the total solid content of the composition. As the alkali-soluble resin used for the insulating layer, the above-described carboxyl group-containing resin, phenolic hydroxyl group-containing resin, or the like, which is a component contained in the resin composition of the present invention, can be used. The photopolymerization initiator and the inorganic filler, which are components contained in the resin composition of the present invention, can be used as the photopolymerization initiator and the inorganic filler used for the insulating layer, respectively. The amount of the alkali-soluble resin used in the insulating layer is preferably 5 to 60% by mass based on the total solid content of the composition. The amount of the photopolymerization initiator used in the insulating layer is preferably 0.01 to 30 parts by mass per 100 parts by mass of the alkali-soluble resin.

The printed circuit board of the present invention is characterized in that the laminated electronic component of the present invention is mounted on at least one of the surface and the inside. In the present invention, the concept of "laminated electronic component" does not include a printed circuit board.

Examples

The present invention will be specifically described below by way of examples and comparative examples thereof, but the present invention is not limited to the following examples. The following "parts" and "%" are all by mass unless otherwise specified.

[ Synthesis of alkali-soluble resin solution A ]

119.4g of novolak-type cresol resin (trade name "Shonol CRG 951", manufactured by Showa Denko K.K., OH equivalent: 119.4), 1.19g of potassium hydroxide, and 119.4g of toluene were added to an autoclave equipped with a thermometer, a nitrogen gas introducing device, an alkylene oxide introducing device, and a stirring device, and the inside of the system was replaced with nitrogen gas while stirring, and the temperature was raised by heating.

Then, 63.8g of propylene oxide was slowly dropped from the alkylene oxide introducing device at 125 to 132 ℃ and 0 to 4.8kg/cm²The reaction was carried out for 16 hours.

Then, 1.56g of 89% phosphoric acid was added and mixed to the reaction solution cooled to room temperature to neutralize potassium hydroxide, thereby obtaining a propylene oxide reaction solution of a novolak-type cresol resin having a solid content of 62.1% and a hydroxyl value of 182.2g/eq. Which is obtained by adding 1.08 moles of alkylene oxide on average per 1 equivalent of phenolic hydroxyl groups.

293.0g of the obtained novolak-type cresol resin alkylene oxide reaction solution, 43.2g of acrylic acid, 11.53g of methanesulfonic acid, 0.18g of methylhydroquinone and 252.9g of toluene were added to a reactor equipped with a stirrer, a thermometer and an air blowing tube, and the mixture was reacted at 110 ℃ for 12 hours while stirring with air blown at a rate of 10 ml/min.

The water produced by the reaction was distilled off as an azeotropic mixture with toluene, and 12.6g was obtained. After that, the obtained reaction solution was cooled to room temperature, neutralized with 35.35g of a 15% aqueous sodium hydroxide solution, and then washed with water. Then, toluene was replaced with 118.1g of diethylene glycol monoethyl ether acetate in an evaporator and removed by distillation to obtain a novolak-type acrylate resin solution.

Next, 332.5g of the obtained novolak type acrylate resin solution and 1.22g of triphenylphosphine were put into a reactor equipped with a stirrer, a thermometer and an air blowing tube, air was blown at a rate of 10 ml/min, 60.8g of tetrahydrophthalic anhydride was slowly added thereto with stirring, and the reaction was carried out at 95 to 101 ℃ for 6 hours. An alkali-soluble resin solution having an acid value of 88mgKOH/g as a solid matter and a solid content of 71% was obtained. This was used as a resin solution A.

[ Table 1]

﹡ 1) Irgacure OXE 02: 1- [ 9-Ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone 1- (O-acetyloxime), manufactured by BASF Japan K.K

﹡ 2) jER 828: bisphenol A epoxy resin having an epoxy equivalent of 184 to 194g/eq, manufactured by Mitsubishi Chemical Corporation, in a liquid state

﹡ 3) DPHA: dipentaerythritol hexaacrylate, manufactured by Nippon Kabushiki Kaisha

﹡4)C.I.Pigment Blue 15：3

﹡5)C.I.Pigment Yellow 147

﹡ 6) SO-C2: silicon dioxide SiO₂D50 ═ 0.5 μm, manufactured by Admatech

< preparation of Dry film >

The photo/thermosetting resin compositions of table 1 and the thermosetting resin compositions of tables 2 to 5 were prepared by mixing the respective components shown in table 1 and tables 2 to 5 at the same time in the proportions (parts by mass) shown in table 1 and tables 2 to 5, stirring and premixing for 15 minutes in a stirrer, and then kneading by a three-roll mill.

Subsequently, the prepared photo/thermosetting resin composition and thermosetting resin composition were applied to a PET film (carrier film) by a lip coater, and dried at 80 ℃ for 10 minutes to form a photo/thermosetting resin composition layer and a thermosetting resin layer having a thickness of 15 μm on the carrier film. Next, a protective film (polypropylene film) was attached to the photo/thermosetting resin composition layer and the thermosetting resin layer to obtain respective dry films.

< production of substrate having insulating layer formed of photo/thermosetting resin composition >

A substrate (500mm × 600mm × 0.4.4 mmt (thickness)) on which a copper circuit was formed as an electrode layer was subjected to an etching treatment equivalent to 0.5 μm by CZ-8101 (manufactured by MEC) as a pretreatment, then the protective film of the dry film of the photo/thermosetting resin composition of Table 1 prepared above was peeled off, the substrate was pasted so that the resin layer side was in contact with the substrate surface, heat-laminated under conditions of a degree of compression of 0.5MPa, 80 ℃ for 1 minute and a degree of vacuum of 133.3Pa by a batch vacuum pressure laminator MVLP-500 (manufactured by CMYO) to obtain a substrate having a resin layer, then the resin layer was exposed from the carrier film by an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), the carrier film was peeled off, and then the spray pressure was 2kg/cm²Under the conditions of (1) wt% Na at 30 deg.C₂CO₃Development was carried out in an aqueous solution for 60 seconds.

Then, the resultant was irradiated with a high-pressure mercury lamp at 1000mJ/cm²And (6) carrying out exposure. Thereafter, the resin layer was cured by heat curing at 180 ℃ for 60 minutes in a hot air circulation type drying furnace to completely cure the resin layer, thereby forming an insulating layer on the electrode layer.

< production of substrate having insulating layer protected by protective layer formed of thermosetting resin composition >

On the substrate produced by the method described in the above < production of substrate having insulating layer formed of light/heat curable resin composition > the protective film of the dry film of heat curable resin composition of tables 2 to 5 produced in the above was peeled off, and the substrate was pasted so that the heat curable resin layer side was in contact with the insulating layer, and the substrate was pressed by an intermittent vacuum pressing laminator MVLP-500 (manufactured by the agency of japan corporation) at a pressing degree: 0.5MPa, 90 ℃,1 minute, vacuum: the heat lamination was performed under 133.3Pa to obtain a substrate having a thermosetting resin layer on the insulating layer. Next, the carrier film was peeled off, and after heating at 100 ℃ for 30 minutes in a hot air circulation type drying furnace, heating was performed at 180 ℃ for 60 minutes to obtain a laminated cured product in which a thermosetting cured film as a protective layer was laminated on a photo/thermosetting cured film as an insulating layer.

< flexibility of film (bending test) >

The flexibility of the dry film was evaluated from the minimum diameter of the mandrel from which cracks and peeling from the carrier film of the dry film of the examples and comparative examples prepared by the method described in < preparation of dry film > described above started to occur, using a cylindrical mandrel bending tester manufactured by BYK-Gardner according to JISK5600-5-1(ISO 1519). The evaluation criteria are as follows. When the flexibility of the dry film is good, the flexibility of the resin layer is high, and cracking and dusting can be suppressed.

◎ is prepared from

The following diameters were all equal to each other, and no cracks or chipping of the resin layer or peeling of the carrier film occurred.

○ is in excess of

And less than 5mm, no crack, powder falling, and carrier film peeling of the resin layer.

× is prepared from

The above diameter causes cracking and chipping of the resin layer and peeling of the carrier film.

< measurement of melt viscosity >

The protective films of the dry films of examples and comparative examples prepared by the method described in < preparation of dry film > were peeled off, the thermosetting resin layer side was adhered, and the resultant was laminated on the surface of the film by a batch vacuum press MVLP-500 (manufactured by kokai corporation) at a pressure ratio of: 0.5MPa, 50 ℃,1 minute, vacuum: and heating lamination is carried out under the condition of 133.3 Pa. The above operation was repeated until the thickness became 330 μm to form a measurement sample. Using this sample, the melt viscosity was measured in an oscillation mode at a strain of 2%, a temperature rise rate of 3 ℃ per minute, a gap of 300 μm, and a frequency of 1Hz using Rheo Stress RS-6000 (manufactured by HAAKE).

Very good: the melt viscosity is 50000 dPas or more and less than 500000 dPas.

O: the melt viscosity is 10000 dPas or more and less than 50000 dPas.

X: the melt viscosity is less than 10000 dPas or more than 500000 dPas.

< determination of glass transition temperature (Tg) and coefficient of thermal expansion (CTE (. alpha.1)) based on TMA >

With respect to the dry film of the thermosetting resin composition prepared by the method described in < preparation of dry film > above, the protective film of the dry film was peeled off, and the film was attached to the glossy surface side (copper foil) of a copper foil F2 (manufactured by guhe industries co., ltd.) and subjected to a batch vacuum press MVLP-500 (manufactured by kokai corporation) at a pressing rate of: 0.5MPa, 90 ℃,1 minute, vacuum: and heating lamination is carried out under the condition of 133.3 Pa. Subsequently, the resin layer was heated at 110 ℃ for 30 minutes in a hot air circulation type drying furnace, and then cured at 180 ℃ for 60 minutes, and then the carrier film was peeled off to obtain a cured product. After that, the cured product was peeled off from the copper foil, and the sample was cut into a measurement size (size of 3mm × 10 mm) and supplied to TMA6100 manufactured by Seiko Instruments Inc. TMA was measured as follows: the sample was heated from room temperature at a temperature rise rate of 10 ℃ per minute under a test load of 5g, and the measurement was performed 2 times continuously. The intersection of 2 tangent lines having different coefficients of thermal expansion at the 2 nd pass was evaluated as the coefficient of thermal expansion between 30 ℃ and 100 ℃ for the glass transition temperature (Tg), and expressed as CTE (. alpha.1).

Evaluation of glass transition temperature (Tg)

Very good: tg is 170 ℃ or higher.

O: tg is more than 150 ℃ and less than 170 ℃.

And (delta): tg is 130 ℃ or higher and less than 150 ℃.

Evaluation of coefficient of thermal expansion (CTE (. alpha.1))

Very good: less than 20 ppm.

O: more than 20ppm and less than 23 ppm.

And (delta): more than 23ppm and less than 25 ppm.

X: above 25 ppm.

< determination of glass transition temperature (Tg) and storage modulus based on DMA >

A sample of a cured product produced by the method described in the foregoing < measurement of glass transition temperature (Tg) and coefficient of thermal expansion based on TMA (CTE (. alpha.1)) > was cut into measurement dimensions (dimensions of 5 mm. times.10 mm) for DMA7100 manufactured by Hitachi High-Tech Science Corporation. Dynamic viscoelasticity measurement (DMA) was as follows: the sample is measured at a measurement temperature of 25 to 300 ℃ and a temperature rise rate of 5 ℃/min, and the glass transition temperature (Tg) and the storage modulus E' at 35 ℃ are measured. It is found that the higher the storage modulus E', the more excellent the handling properties of the laminated electronic component.

Evaluation of glass transition temperature (Tg)

Very good: tg is 180 ℃ or higher.

O: tg is above 160 ℃ to below 180 ℃.

And (delta): tg is more than 140 ℃ and less than 160 ℃.

Evaluation of storage modulus E

Very good: 18GPa or more.

O: 15GPa or more and less than 18 GPa.

And (delta): 10GPa or more and less than 15 GPa.

X: less than 10 GPa.

< determination of dielectric constant (Dk) and dielectric loss tangent (Df) >)

The dielectric constant (Dk) and dielectric loss tangent (Df) at 23 ℃ at 10GHz were measured for the cured product prepared by the methods described in < measurement of glass transition temperature (Tg) and coefficient of thermal expansion (CTE (α 1)) based on TMA using an SPDR dielectric resonator and a network analyzer (both of Agilent corporation). The judgment criteria are as follows.

Evaluation of dielectric constant (Dk)

Very good: more than 3.0 and less than 3.5.

O: more than 3.5 and less than 4.0.

X: 4.0 or more

Evaluation of dielectric loss tangent (Df)

Very good: less than 0.01.

O: 0.01 or more and less than 0.02.

X: 0.02 or more

< circuit concealment >

In the case of the substrate produced by the method described in the above < production of a substrate having an insulating layer protected by a protective layer formed of a thermosetting resin composition >, the discoloration of the copper circuit was visually observed from the cured film, and the concealing property of the circuit was evaluated.

Very good: discoloration was not observed.

Good: discoloration was slightly observed.

X: discoloration was confirmed.

< visibility (difference in reflectance (protective layer and insulating layer)) >)

The cured film surface of the substrate produced by the method described in < production of substrate having insulating layer formed of photo/thermosetting resin composition > was measured for reflectance at wavelength of 360 to 740nm and for reflectance of insulating layer at wavelength of 450nm with a spectrophotometer (CM-2600d, manufactured by Konica Minolta Sensing Inc.). Next, the reflectance at a wavelength of 360 to 740nm was measured in the same manner for the surface of the protective layer of the substrate manufactured by the method described in "manufacturing of substrate having insulating layer protected by protective layer formed of thermosetting resin composition" above, and the reflectance at a wavelength of 450nm of the protective layer was measured. The difference in reflectance between the protective layer and the insulating layer at 450nm was calculated from the following equation.

Reflectance (%) of the protective layer-reflectance (%) of the insulating layer

The criterion is as follows.

Very good: very excellent visibility (difference in reflectance of 20% or more.)

O: excellent visibility (difference in reflectance of 10% or more and less than 20%)

X: poor visibility (difference in reflectance less than 10%)

When the laminated electronic component shown in fig. 1 is inspected by an AOI inspection machine (manufactured by Orbotech), a fine component having a side of less than 1mm, such as a cube, having the same length, can be inspected for appearance without erroneous recognition of the upper and lower sides of the protective layer and the side of the inner layer.

< reflow resistance (reflectance after heating and before heating) >)

The evaluation substrate produced by the method described in "production of substrate having insulating layer protected by protective layer formed of thermosetting resin composition" used in the above < visibility (difference in reflectance (protective layer and insulating layer)) > was subjected to reflow treatment 5 times at a heating temperature of 260 ℃ in accordance with the IPC/JETEC J-STD-020 standard, and the reflectance at a wavelength of 360 to 740nm was measured with a spectrophotometer (CM-2600d, manufactured by Konica Minolta Sensing inc.) on the surface of the coating film after reflow treatment, and the difference in reflectance between after heating and before heating was evaluated. The 5-time reflow treatment means an operation of repeating 5-time passes through an infrared oven at 260 ℃ for 10 seconds and returning to normal temperature.

Very good: the difference in reflectance before and after heating was less than 3%.

O: the difference in reflectance between before and after heating is 3% or more and less than 5%.

X: the difference in reflectance before and after heating is 5% or more.

< embeddability (generation of bubble FLS (thin line & space)) >)

As a pretreatment, an etching treatment equivalent to 0.5 μm was performed on a double-sided printed circuit board having a copper thickness of 10 μm, an aspect ratio of 2.0 and a comb-patterned fine circuit formed therein, wherein L (line: wiring width)/S (space: space width) is 5/5 μm, by CZ-8101, manufactured by MEC corporation. Next, the protective film of the dry film of the thermosetting resin composition prepared in the above < preparation of dry film > was peeled off, and the protective film was attached so that the thermosetting resin layer side was in contact with the substrate surface, and the resultant was subjected to a batch vacuum pressing using a batch vacuum pressing laminator MVLP-500 (manufactured by japan corporation) at a pressing degree: 0.5MPa, 90 ℃,1 minute, vacuum: the heat lamination was performed under 133.3Pa to obtain a substrate having a thermosetting resin layer. Subsequently, the carrier film was peeled off, and the film was heated at 100 ℃ for 30 minutes and then at 180 ℃ for 60 minutes in a hot air circulation type drying furnace to obtain a thermosetting film. After thermal curing, air enters the boundary portion between the line and the space, and whether or not air bubbles (voids) occur is evaluated at 100.

Very good: no voids were identified.

O: gaps at 1 to 3 positions were observed.

X: a gap of 4 or more was confirmed.

< lattice drawing test >

For the substrate produced in the above < production of a substrate having an insulating layer protected by a protective layer formed of a thermosetting resin composition > the peeling test of the protective layer was evaluated by introducing cross-cuts in a checkered pattern according to the test method of JIS D0202 and performing a peeling test of the adhesive tape. The criterion for the determination is as follows.

O: peeling was not observed at all.

X: there is a case where peeling occurs in the protective layer.

[ Table 2]

﹡ 7) EPOX-MKR 710: bisphenol E type epoxy resin having an epoxy equivalent of 160 to 180g/eq manufactured by Printec corporation, liquid state

﹡ 8) jER 828: bisphenol A epoxy resin having an epoxy equivalent of 184 to 194g/eq, manufactured by Mitsubishi Chemical Corporation, in a liquid state

﹡ 9) jER 807: bisphenol F epoxy resin, manufactured by Mitsubishi Chemical Corporation, having an epoxy equivalent of 160 to 175g/eq, liquid

﹡ 10) HP-7200L: a dicyclopentadiene type epoxy resin having an epoxy equivalent of 250 to 280g/eq and a softening point of 57 to 68 ℃ manufactured by DIC K.K

﹡ 11) HP-4032: naphthalene epoxy resin, DIC product, epoxy equivalent 135-165 g/eq, semi-solid

﹡ 12) HF-1M: phenol novolac resin, produced by Minghua chemical Co., Ltd., hydroxyl group equivalent of 104 to 108g/eq, softening point of 82 to 86 DEG C

﹡ 13) LA-1356: triazine structure-containing phenol novolak resin having hydroxyl equivalent weight of 146g/eq, available from DIC corporation

﹡ 14) EXB-8500: an active ester resin having a softening point of 135 ℃ and a softening point of 223g/eq, manufactured by DIC K.K

﹡ 15) PRIMASET PT-30: novolac type isocyanate resin manufactured by Lonza Japan Ltd., isocyanate equivalent 124g/eq

﹡ 16) FX-293: phenoxy resin, Nippon Tekken chemical Co., Ltd., molecular weight of 40,000 to 50,000, Tg158 ℃ C

﹡ 17) CUREZOL 1B2 PZ: 2-phenyl-1-benzyl-1H-imidazole, liquid manufactured by Siguo Kasei Kogyo

﹡ 18)4 DMAPy: 4-dimethylaminopyridine, product of Kyoto chemical industries, Ltd

﹡ 19) CO (II): cobalt (II) acetylacetonate, manufactured by Tokyo chemical industry Co., Ltd

﹡ 20) BiNFi-s: ultrafine fibrous biomass nanofiber manufactured by SUGINO MACHINE LIMITED

﹡ 21) KBM-602: n-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, a product of shin-Etsu chemical Co., Ltd

﹡ 22) IRGANOX 1076: heat-resistant stabilizer for polymer, hindered phenol antioxidant manufactured by BASF Japan K.K

﹡ 23) SO-C2: silicon dioxide SiO₂D50 ═ 0.5 μm, manufactured by Admatech

﹡ 24) YA 050C: silicon dioxide SiO₂Manufactured by Admatechs corporation, D50 ═ 50nm

﹡25)Tipaque CR-953：TiO₂Manufactured by stone industries, Ltd., average particle diameter of 0.28. mu.m

﹡ 26) Cyclohexanone: solvent(s)

﹡ 27) toluene: solvent(s)

﹡ 28) MEK: methyl ethyl ketone and solvent

[ Table 3]

[ Table 4]

[ Table 5]

From the results shown in the above table, it is understood that: according to the resin composition for a laminated electronic component of the present invention, a laminated electronic component excellent in visibility and workability in appearance inspection can be produced.

Description of the reference numerals

11 laminated electronic component

12a, 12b, 12c, 12d, 12e, 12f electrode layer

13a, 13b, 13c, 13d, 13e, 13f insulating layer

14a, 14b protective layer

15a, 15b external electrode

Claims

1. A resin composition for a protective layer of a laminated electronic component, characterized in that the resin composition is used for a protective layer of a laminated electronic component in which electrode layers and insulating layers are alternately laminated and the protective layer is provided on both end surfaces in a laminating direction,

the resin composition comprises: a curable resin, an inorganic filler, and a colorant.

2. The resin composition for laminated electronic components according to claim 1, wherein the inorganic filler comprises at least 2 inorganic fillers having different average particle diameters.

3. The resin composition for laminated electronic components according to claim 1, wherein the inorganic filler comprises silica.

4. The resin composition for laminated electronic components according to claim 1, wherein the colorant is a white colorant.

5. The resin composition for laminated electronic components according to claim 4, wherein the white colorant is titanium oxide.

6. The resin composition for laminated electronic components according to claim 5, wherein the titanium oxide is contained in an amount of 10 mass% or less based on the total solid content of the composition.

7. A dry film comprising a resin layer obtained by applying the resin composition for laminated electronic parts according to claim 1 to a film and drying the resin composition.

8. A cured product obtained by curing the resin composition for laminated electronic parts according to any one of claims 1 to 6 or the resin layer of the dry film according to claim 7.

9. A laminated electronic component, which is characterized by alternately laminating electrode layers and insulating layers and providing protective layers comprising the cured product according to claim 8 on both end surfaces in the laminating direction.

10. The laminate-type electronic component according to claim 9, wherein the insulating layer is formed from an alkali-developable resin composition comprising an alkali-soluble resin, a photopolymerization initiator, and an inorganic filler.

11. The laminated electronic component according to claim 9, which is an inductor.

12. A printed circuit board, wherein the laminated electronic component according to claim 9 is mounted on at least one of a surface and an interior thereof.