TWI846846B - Dry films, hardened materials and electronic parts - Google Patents

Abstract

The dry film (11) has a hardening resin layer (12) composed of a light-shielding hardening resin composition including a polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, a coloring agent, and an inorganic filler. When the thickness of the hardening resin layer (12) is set to X (μm), the maximum particle size of the aggregated particles of the inorganic filler is less than X/2 (μm). The dry film (11) has excellent light-shielding properties, and warping is suppressed. In addition, burrs or defects during cutting can be suppressed.

Description

Dry films, hardened materials and electronic parts

The present invention relates to a dry film, a hardened material and an electronic component.

In the past, one of the means of forming a protective film or insulating layer such as a solder resist or an interlayer insulating layer provided on a printed wiring board used in electronic equipment, etc., was to use a dry film (laminated film) (for example, Patent Document 1). A dry film has a resin layer obtained by applying a resin composition having desired properties on a carrier film and then drying it. Generally, it is circulated in the market in a state where a protective film is laminated to protect the side opposite to the carrier film. After the resin layer of the dry film is pasted (hereinafter also referred to as "laminated") on a substrate, a printed wiring board having the above-mentioned protective film or insulating layer can be manufactured by applying a patterning or curing treatment. Prior art literature Patent literature

Patent document 1: Japanese Patent Application Publication No. 2015-010179

Invent the problem you want to solve

Dry film is also used as a packaging material for semiconductor chips. After the dry film laminated on the semiconductor wafer is hardened to form a packaging material, it is cut into individual semiconductor chips using a blade-type cutter. During this cutting, burrs are generated at the cut ends of the packaging material, or defects are generated in the packaging material. In addition, after the semiconductor chip is packaged, the film thickness of the packaging material on the chip becomes thinner, but even in this case, it is required to block external light and protect the semiconductor chip. In addition, the partition wall in the optical sensor module or the material configured around each RGB light-emitting element in the display using micro LED requires a resin with high light-shielding properties, but the current resins may not have sufficient light-shielding properties. In addition, dry film is sometimes required to have low light transmittance in other applications such as black solder resist. In addition, dry film is required to have less warping on the substrate during curing in order to ensure that the resin layer and the substrate are sufficiently adhered.

Therefore, the purpose of the present invention is to provide a dry film, hardened material, and electronic component that has excellent light-shielding properties, suppresses warping, and suppresses burrs or defects during cutting. Means for solving the problem

The inventors of the present invention have conducted intensive research to solve the above-mentioned problems and have found that a dry film having a curable resin layer composed of a light-shielding curable resin composition including a polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, a coloring agent, and an inorganic filler has excellent dispersibility and sufficient light-shielding properties, and warping is suppressed, thereby suppressing burrs or defects during cutting.

That is, the dry film of the present invention is characterized by having a curable resin layer composed of a light-shielding curable resin composition including a polymer resin with a glass transition temperature of less than 20°C and a weight average molecular weight of more than 10,000, a colorant, and an inorganic filler, and when the thickness of the curable resin layer is set to X (μm), the maximum particle size of the agglomerated particles of the inorganic filler is less than X/2 (μm). In the present invention, light-shielding property means that the transmittance of the curable resin layer in the full wavelength range of 380-780nm in the film thickness of 40μm is less than 0.5%.

In the dry film of the present invention, the maximum particle size of the aggregated particles of the inorganic filler is preferably 10 μm or less, the amount of the inorganic filler is preferably 0.1-70% by mass relative to the solid content of the light-shielding curable resin composition, the amount of the colorant is preferably 0.3-20% by mass relative to the solid content of the light-shielding curable resin composition, and the amount of the polymer resin having a glass transition temperature of 20° C. or less and a weight average molecular weight of 10,000 or more is preferably 1-35% by mass relative to the solid content of the light-shielding curable resin composition. The curable resin layer preferably further includes a liquid epoxy resin.

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

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

According to the present invention, a dry film, a cured product, and an electronic component can be provided which have excellent light-shielding properties, are warped, and can suppress burrs or defects during cutting.

The dry film, hardened material and electronic components of the present invention are described in more detail below. FIG. 1 is a schematic cross-sectional view of a dry film 11 of one embodiment of the present invention. The dry film 11 shown in FIG. 1 is a three-layer structure in which a hardening resin layer 12 is formed on a carrier film 13 and a protective film 14 is laminated. If necessary, the dry film 11 may have other resin layers between the protective film and the hardening resin layer, or between the supporting film and the hardening resin layer.

<Hardening resin layer> The dry film of the present invention has a curable resin layer composed of a light-shielding curable resin composition including a polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, a coloring agent, and an inorganic filler. When the thickness of the curable resin layer is set to X (μm), the maximum particle size of the aggregated particles of the inorganic filler is less than X/2 (μm).

Inorganic fillers inhibit the curing shrinkage of the resulting cured product, and can improve the adhesion, hardness, and crack resistance of the conductive layer such as copper bonded around the insulating layer and the coefficient of linear expansion (CTE). Of course, inorganic fillers will aggregate when the light-shielding curable resin composition is prepared to form ink. Through the research of the present inventors, it is known that when the aggregated particles of the agglomerated inorganic filler are large, burrs or defects are easily generated during cutting. In addition, the light-shielding property (low transmittance) of the cured product is improved by including a coloring agent such as carbon black in the curable resin composition. Through the research of the present inventors, it is known that when the aggregated particles of the agglomerated inorganic filler are large, the inorganic filler is likely to scatter light in the cured product, which is not conducive to light-shielding properties. Therefore, when the thickness of the curable resin layer is set to X (μm), the maximum particle size of the aggregated particles of the inorganic filler is less than X/2 (μm), which can suppress burrs or defects during cutting and improve light shielding properties in the thin film on the semiconductor chip.

In addition, the curable resin layer, by including a polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, suppresses the aggregation of the colorant and the inorganic filler, improves the dispersibility of the colorant and the inorganic filler, and suppresses sedimentation, and in particular, can simultaneously improve the light-shielding property and the long-term stability of the curable resin composition. In addition, the warping of the cured product can be suppressed. The curable resin layer of the dry film is generally referred to as the state of the B stage state, which is obtained from the light-shielding curable resin composition. The following describes each component.

[Polymer resin with a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more] The glass transition temperature of a polymer resin with a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more is preferably -40~20°C, more preferably -15~15°C, and particularly preferably -5~15°C. At -5~15°C, the warping of the cured product can be well suppressed. In addition, since the higher the weight average molecular weight of the polymer resin, the greater the effect of preventing the sedimentation of the colorant and inorganic filler, it is preferably 100,000 or more, and more preferably 200,000 or more. The upper limit is, for example, 1 million or less, and preferably 500,000 or less.

Examples of the polymer resin include polymer resins having one or more skeletons selected from a butadiene skeleton, an amide skeleton, an imide skeleton, an acetal skeleton, a carbonate skeleton, an ester skeleton, a urethane skeleton, an acryl skeleton, and a siloxane skeleton. For example, polymer resins having a butadiene skeleton ("G-1000", "G-3000", "GI-1000", "GI-3000" manufactured by Nippon Soda Co., Ltd., "R-45EPI" manufactured by Idemitsu Kosan Co., Ltd., "PB3600", "Epofriend AT501" manufactured by Daicel Co., Ltd., "Ricon130", "Ricon142", "Ricon150", "Ricon657", "Ricon130MA" manufactured by Cray Valley Co., Ltd.), polymer resins having a butadiene skeleton and a polyimide skeleton (described in Japanese Patent Publication No. 2006-37083), polymer resins having an acryl skeleton (nagase "SG-P3", "SG-600LB", "SG-280", "SG-790", "SG-K2" manufactured by Chemtex, "SN-50", "AS-3000E", "ME-2000" manufactured by Negami Industries, etc.

The polymer resin is preferably an acrylic copolymer having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more from the viewpoint of flatness of the cured product. Furthermore, from the viewpoint of suppressing the dispersibility of the colorant and the inorganic filler and the sedimentation of the composition, an acrylic copolymer having a glass transition temperature of 20°C or less and a weight average molecular weight of 100,000 to 1,000,000 is preferred, and an acrylic copolymer having a glass transition temperature of -5 to 15°C and a weight average molecular weight of 200,000 to 500,000 is more preferred.

The acrylic acid ester copolymer may have a functional group, and examples of the functional group include a carboxyl group, a hydroxyl group, an epoxy group, and an amide group.

The acrylic ester copolymer preferably has an epoxy group, and more preferably has an epoxy group and an amide group. The epoxy group can suppress the warping of the cured product.

Examples of the acrylic ester copolymer include Teisanresin SG-70L, SG-708-6, WS-023 EK30, SG-P3, SG-80H, SG-280 EK23, SG-600TEA, and SG-790 manufactured by Nagase Chemtex. The acrylic ester copolymer can also be synthesized, and the synthesis method can be, for example, the synthesis method described in Japanese Patent Application Publication No. 2016-102200.

The polymer resin may be used alone or in combination of two or more. The amount of the polymer resin is preferably 1 to 35% by weight, more preferably 1 to 30% by weight, based on the total amount of the solid components of the composition. Within the above range, the dispersibility of the inorganic filler or the long-term stability of the composition can be improved. In particular, when the amount of the polymer resin is 5% by weight or more, a cured film with low transmittance and suppressed warping of the substrate can be obtained.

In addition, in this specification, the value of weight average molecular weight (Mw) can be measured by gel permeation chromatography (GPC) method (polystyrene standard), for example, using the following measuring device and measuring conditions. Measuring device: "Waters 2695" manufactured by Waters Detector: "Waters 2414" manufactured by Waters, RI (differential refractometer) Column: "HSPgel Column, HR MB-L, 3μm, 6mm×150mm" manufactured by Waters × 2 + "HSPgel Column, HR1, 3μm, 6mm×150mm" manufactured by Waters × 2 Measuring conditions: Column temperature: 40℃ RI detector setting temperature: 35℃ Developing solvent: tetrahydrofuran Flow rate: 0.5mL/min Sample volume: 10μL Sample concentration: 0.7 mass%

[Colorant] As a colorant, there is no particular limitation as long as it can obtain a light-shielding curable resin composition, and a well-known and commonly used black colorant can be used. Specifically, carbon black, titanium black, iron oxide, cobalt oxide, perylene-based black colorants, etc. can be listed, and these colorants can be used alone or in combination. The colorant can also be a perylene-based colorant, or a combination of the perylene-based colorant and a colorant related to a complementary colorant, and the light-shielding property can be exhibited by the combination. Perylene-based colorants have colors such as green, yellow, orange, red, purple, and black, and the following ones with a color index (C.I.; issued by The Society of Dyers and Colourists) number can be listed. - Green: Solvent Green 5 - Orange: Solvent Orange 55 - Red: Solvent Red 135, 179; Pigment Red 123, 149, 178, 179, 190, 194, 224 - Purple: Pigment Violet 29 - Black: Pigment Black 31, 32 Perylene-based colorants other than those listed above may also be used, such as BASF's Lumogen (registered trademark) Black FK4280 and Lumogen Black FK4281, which have no color index number but are known as near-infrared penetrating black organic pigments, and Lumogen F Yellow 083, Lumogen F Orange 240, Lumogen F Red 305, and Lumogen F Green850, like other perylene compounds, has low absorption in the ultraviolet region and high coloring power, so it is suitable for use.

In the present invention, the coloring agent used in combination with the perylene coloring agent is described below. First, the coloring relationship in the present invention is described. Since the coloring agent may not present the color as the color index color, the appearance color tone of the cured coating of the resin composition is measured and displayed by the method specified in JIS Z8729, and the a* value and b* value of the color in the L*a*b* color system are confirmed and displayed with the coordinate axis (refer to Figure 2), and the coloring agent used for the cured coating obtained by combining with the perylene coloring agent and (a* value, b* value) infinitely close to (0, 0) is selected as the coloring agent of the coloring relationship. Here, the film thickness of the cured coating is not particularly limited, for example, 40μm. Moreover, the (a* value, b* value) infinitely close to (0, 0) has an a value and a b value in the range of -5 to +5, preferably in the range of -2 to +2. Furthermore, the coloring agent of the color-complementing relationship may be a perylene-based coloring agent or a coloring agent other than a perylene-based coloring agent.

When the color system a* value and b* value of the color system of the perylene-based colorant and the colorant in the color complement relationship are close to 0, the colorant can be any colorant. The following colorants can be listed. More preferred combinations of perylene colorants and colorants with complementary coloring agents include, for example, combinations of Pigment Red 149, 178, 179 and green anthraquinone colorants (Solvent Green 3, Solvent Green 20, Solvent Green 28, etc.). When perylene colorants are mixed (combined) with each other, combinations of red perylene colorants (Pigment Red 149, 178, 179) and black perylene colorants (Pigment Black 31, 32) and combinations of black perylene colorants (Lumogen (registered trademark) Black FK4280, 4281) that are the same as the black perylene colorants (Pigment Black 31, 32).

Furthermore, the coloring agent may be any combination selected from the group consisting of a yellow coloring agent and a purple coloring agent, a yellow coloring agent, a blue coloring agent, and a red coloring agent, a green coloring agent and a purple coloring agent, a green coloring agent and a red coloring agent, a yellow coloring agent, a purple coloring agent, and a blue coloring agent, and a green coloring agent, a red coloring agent, and a blue coloring agent, and the resin composition may have light-shielding properties by using the combination. In addition, a purple coloring agent, an orange coloring agent, a brown coloring agent, etc. may also be used in combination.

Blue colorants include phthalocyanine and anthraquinone, and there are compounds classified as pigments (pigment) and solvents (solvent). In addition, metal-substituted or unsubstituted phthalocyanine compounds can also be used. Red colorants include monoazo, disazo, azochromatin, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, and quinacridone. Yellow colorants include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, and anthraquinone. Green colorants include phthalocyanine and anthraquinone. In addition, metal-substituted or unsubstituted phthalocyanine compounds can also be used.

Purple colorant, orange colorant, brown colorant, specifically, Pigment Violet 19, 23, 29, 32, 36, 38, 42; Solvent Violet 13, 36; C.I. Paint Orange 1, C.I. Paint Orange 5, C.I. Paint Orange 13, C.I. Paint Orange 14, C.I. Paint Orange 16, C.I. Paint Orange 17, C.I. Paint Orange 24, C.I. Paint Orange 34, C.I. Paint Orange 36, C.I. Paint Orange 38, C.I. Paint Orange 40, C.I. Paint Orange 43, C.I. Paint Orange 46, C.I. Paint Orange 49, C.I. Paint Orange 51, C.I. Paint Orange 61, C.I. Paint Orange 63, C.I. Paint Orange 64, C.I. Paint Orange 71, C.I. Paint Orange 73; C.I. Paint Brown 23, C.I. Paint Brown 25; C.I. Paint Black 1, C.I. Paint Black 7, etc. The amount of the colorant to be added is not particularly limited, but is preferably 0.3 to 20 parts by weight relative to the total amount of the solid components of the composition. By setting the amount to 0.3 parts by weight or more, the light-shielding property can be improved. By setting the amount to 20 parts by weight or less, a composition with excellent dispersibility can be obtained.

Carbon black can be dispersed in a resin to obtain light-shielding properties. Carbon black generally used for black coloring agents can be used. Carbon black can be one or more of the known carbon blacks such as channel black, furnace black, thermal black, and lamp black. In addition, resin-coated carbon black can also be used. In addition, carbon nanofibers and carbon nanotubes can also be used. When carbon black is mixed with a resin composition, carbon black powder can be added or a carbon black dispersion can be added. The average particle size of carbon black is preferably 10 nm to 500 nm, more preferably 10 nm to 300 nm, and particularly preferably 10 nm to 100 nm. In addition, the average particle size is the arithmetic mean diameter obtained by observation under an electron microscope.

The amount of carbon black blended is preferably 0.1 to 20% by mass based on the total amount of solid components of the light-shielding curable resin composition. A blending amount of carbon black of 0.1% by mass or more can obtain sufficient light-shielding properties, and a blending amount of 20% by mass or less can suppress the occurrence of cracks. In addition, the greater the blending amount of carbon black, the easier it is to precipitate, but by including the aforementioned polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, the precipitation of carbon black can be suppressed. Here, the blending amount of the polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more and the blending amount of carbon black, expressed in terms of mass ratio, is preferably 1:1 to 100:1.

[Inorganic filler] The curable resin layer contains an inorganic filler. By adding the inorganic filler, the curing shrinkage of the obtained cured product can be suppressed, and the thermal properties such as adhesion, hardness, and crack resistance due to the combination with the conductive layer such as copper located around the insulating layer and CTE can be improved. The inorganic filler may be any conventionally known inorganic filler, but is not limited to any particular one. Examples of the inorganic filler include barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, silica particles, alumina, magnesium carbonate, calcium carbonate, titanium oxide, aluminum oxide, aluminum hydroxide, silicon nitride, aluminum nitride, calcium zirconate, or metal powders such as copper, tin, zinc, nickel, silver, palladium, aluminum, iron, cobalt, gold, and platinum. Spherical particles are preferred for the inorganic filler. Among them, silicon dioxide is preferred, which can suppress the curing shrinkage of the hardened material of the curable composition, thereby achieving a lower CTE and improving properties such as adhesion and hardness.

The inorganic filler may be surface treated. The surface treatment may be surface treatment with a coupling agent or surface treatment without introducing an organic group such as alumina treatment. The surface treatment method of the inorganic filler is not particularly limited, and a conventionally known method may be used. The surface of the inorganic filler may be treated with a surface treatment agent having a curable reactive group, such as a coupling agent having a curable reactive group as an organic group.

The surface treatment of the inorganic filler is preferably performed by using a coupling agent. The coupling agent may be a silane-based, titanate-based, aluminate-based, or zircoaluminate-based coupling agent. Among them, a silane-based coupling agent is preferred. Examples of the silane coupling agent include vinyl trimethoxysilane, vinyl triethoxysilane, N-(2-aminomethyl)-3-aminopropyl methyl dimethoxysilane, N-(2-aminoethyl)-3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3-anilinopropyl trimethoxysilane, 3-glycidyloxypropyl trimethoxysilane, 3-glycidyloxypropyl methyl dimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, 3-methacryloyloxypropyl trimethoxysilane, 3-butylenepropyl trimethoxysilane, etc. These can be used alone or in combination. The silane coupling agent is preferably immobilized in advance by adsorption or reaction on the surface of the inorganic filler. Here, the amount of the coupling agent to be used is, for example, 0.5 to 10 parts by weight relative to 100 parts by weight of the inorganic filler.

The curable reactive group is preferably a thermosetting reactive group. Examples of the thermosetting reactive group include hydroxyl, carboxyl, isocyanate, amino, imino, epoxy, oxetanyl, butyl, methoxymethyl, methoxyethyl, ethoxymethyl, ethoxyethyl, and oxazoline. Among them, at least one of amino and epoxy is preferred. In addition, the surface-treated inorganic filler may also have a photocurable reactive group in addition to the thermosetting reactive group.

In addition, the surface-treated inorganic filler can be included in the hardening resin layer in a surface-treated state. In the hardening resin composition forming the hardening resin layer, the inorganic filler and the surface treatment agent can be separately prepared. In the composition, the inorganic filler can be surface-treated, but it is preferred to prepare the inorganic filler that has been surface-treated in advance. By preparing the inorganic filler that has been surface-treated in advance, it is possible to prevent the reduction of crack resistance and the like due to the surface treatment agent that is not consumed by the surface treatment remaining during the preparation. When the surface treatment is performed in advance, it is preferred to prepare a pre-dispersion liquid in which the inorganic filler is pre-dispersed in the solvent or the curable resin, and it is preferred to pre-disperse the surface-treated inorganic filler in the solvent and mix the pre-dispersion liquid in the composition, or it is preferred to pre-disperse the surface-untreated inorganic filler in the solvent and mix the pre-dispersion liquid in the composition after the surface treatment is performed sufficiently. The inorganic filler can be mixed with other components of the curable resin composition in a powder or solid state, or it can be mixed with a solvent or a dispersant as a slurry and then mixed with other components.

When the thickness of the curable resin layer is set to X (μm), the maximum particle size of the agglomerated particles of the inorganic filler is less than X/2 (μm). By setting the maximum particle size of the agglomerated particles to less than half the thickness of the curable resin layer, the scattering of light caused by the inorganic filler can be suppressed in the curable resin layer, and sufficient light shielding can be obtained. In addition, the inclusion of inorganic fillers is beneficial for suppressing burrs during cutting, but when the maximum particle size of the agglomerated particles is large, burrs are more likely to occur, and defects are more likely to occur during cutting. The maximum particle size of the agglomerated particles of the inorganic filler satisfies the relationship with the film thickness of the curable resin layer mentioned above, and is preferably less than 10μm. By setting the maximum particle size of the agglomerated particles of the inorganic filler to less than 10μm, burrs or defects during cutting can be more effectively suppressed. The polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more can improve the dispersibility of the inorganic filler. Therefore, the curable resin composition including the polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more has excellent dispersion stability in the state of ink and can inhibit the aggregation of the inorganic filler. Therefore, the ink, that is, the curable resin composition, can maintain the maximum particle size of the aggregated particles of the inorganic filler below 10μm even after the long-term storage.

The inorganic filler may be used alone or as a mixture of two or more. The amount of the inorganic filler to be added is preferably 0.1 to 70% by mass based on the total solid content of the curable resin layer of the dry film. When the amount of the inorganic filler is 0.1% by mass or more, thermal expansion can be suppressed and heat resistance can be improved, while when it is 70% by mass or less, cracking can be suppressed. In addition, when the amount of the inorganic filler is 20% by mass or more, cutting resistance can be improved, which is preferred.

[Epoxy resin] The light-shielding curable resin composition may include an epoxy resin. The epoxy resin is a resin having an epoxy group, and any conventionally known epoxy resin may be used. Examples thereof include a bifunctional epoxy resin having two epoxy groups in the molecule, a polyfunctional epoxy resin having three or more epoxy groups in the molecule, and the like. In addition, a hydrogenated epoxy resin may be used. The epoxy resin includes a solid epoxy resin, a liquid epoxy resin, a semi-solid epoxy resin, or a crystallized epoxy resin, and it is preferred that at least a liquid epoxy resin is included. The solid epoxy resin and the liquid epoxy resin may be used alone or in combination of two or more. In this specification, solid epoxy resin refers to epoxy resin that is solid at 40°C, semi-solid epoxy resin refers to epoxy resin that is solid at 20°C and liquid at 40°C, and liquid epoxy resin refers to epoxy resin that is liquid at 20°C. The determination of liquid state is carried out in accordance with the "Method for Confirming Liquid State" in Annex 2 of the Ministerial Order on the Test and Properties of Dangerous Substances (Ministerial Order No. 1 of the First Year of Heisei). For example, it is carried out by the method described in paragraphs 23 to 25 of Japanese Patent Publication No. 2016-079384. In addition, crystalline epoxy resin refers to an epoxy resin with strong crystallinity. At a temperature below the melting point, the polymer chain is properly and regularly arranged. Although it is a solid resin, when melted, it becomes a low-viscosity thermosetting epoxy resin like a general liquid resin.

Examples of the liquid epoxy resin include bisphenol A type epoxy resin, bisphenol F 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 lipid epoxy resin. By including the liquid epoxy resin, the dry film has excellent flexibility.

Solid epoxy resins include naphthalene-based epoxy resins such as HP-4700 (naphthalene-based epoxy resin) manufactured by DIC Corporation and NC-7000 (polyfunctional solid epoxy resin containing a naphthalene skeleton) manufactured by Nippon Kayaku Co., Ltd.; epoxides (triphenol-based epoxy resins) of condensates of phenols and aromatic aldehydes having phenolic hydroxyl groups such as EPPN-502H (triphenol-based epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; EPICLON manufactured by DIC Corporation; HP-7200H (a multifunctional solid epoxy resin containing a dicyclopentadiene skeleton) and other dicyclopentadiene aralkyl epoxy resins; NC-3000H (a multifunctional solid epoxy resin containing a biphenyl skeleton) and other biphenyl aralkyl epoxy resins manufactured by Nippon Kayaku Co., Ltd.; NC-3000L and other biphenyl/phenol novolac epoxy resins manufactured by Nippon Kayaku Co., Ltd.; EPICLON N660, EPICLON N690, N770 manufactured by DIC Corporation, EOCN-104S and other novolac epoxy resins manufactured by Nippon Kayaku Co., Ltd.; NIPPON STEEL Chemical & Phosphorus-containing epoxy resins such as TX0712 manufactured by Material Co., Ltd.; tris(2,3-epoxypropyl)isocyanurate such as TEPIC manufactured by Nissan Chemical Co., Ltd. By including solid epoxy resin, the glass transition temperature of the cured product becomes higher and the heat resistance is excellent.

The semi-solid epoxy resin is preferably at least one selected from the group consisting of bisphenol A type epoxy resin, naphthalene type epoxy resin and phenol novolac type epoxy resin. By including the semi-solid epoxy resin, the glass transition temperature (Tg) of the cured product becomes higher, the CTE becomes lower, and the crack resistance is excellent. Semi-solid epoxy resins include bisphenol A type epoxy resins such as EPICLON 860, EPICLON 900-IM, EPICLON EXA-4816, EPICLON EXA-4822 manufactured by DIC Corporation, EPOTOHTOYD-134 manufactured by NIPPON STEEL Chemical & Material Co., Ltd., jER834, jER872 manufactured by Mitsubishi Chemical Co., Ltd., and ELA-134 manufactured by Sumitomo Chemical Co., Ltd.; naphthalene type epoxy resins such as EPICLON HP-4032 manufactured by DIC Corporation; phenol novolac type epoxy resins such as EPICLON N-740 manufactured by DIC Corporation, etc.

Crystalline epoxy resins that can be used include, for example, those having a biphenyl structure, a sulfide structure, a phenylene structure, a naphthalene structure, and the like. Biphenyl-type epoxy resins include, for example, jER YX4000, jER YX4000H, jER YL6121H, jER YL6640, and jER YL6677 manufactured by Mitsubishi Chemical. Diphenyl sulfide-type epoxy resins include, for example, EPOTOHTOYSLV-120TE manufactured by NIPPON STEEL Chemical & Material. Phenyl-type epoxy resins include, for example, EPOTOHTOYDC-1312 manufactured by NIPPON STEEL Chemical & Material. As the naphthalene type epoxy resin, for example, EPICLON HP-4032, EPICLON HP-4032D, and EPICLON HP-4700 manufactured by DIC Corporation can be used. As the crystalline epoxy resin, EPOTOHTOYSLV-90C manufactured by NIPPON STEEL Chemical & Material Co., Ltd. and TEPIC-S (triglycidyl isocyanurate) manufactured by Nissan Chemical Co., Ltd. can be used.

The amount of epoxy resin to be added is preferably 1-70% by weight based on the total solid content of the composition. When it is within the above range, the heat resistance, flexibility or crack resistance of the cured product is excellent. In addition, the amount of liquid epoxy resin to be added is preferably 5-60% by weight based on the total solid content of the epoxy resin, the hardener, the hardening accelerator and the above-mentioned polymer resin. When it is within the above range, the softness of the dry film is excellent.

The light-shielding curable resin composition may contain curable resin components other than epoxy resins within a range not impairing the effects of the present invention. For example, known conventional thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional cyclobutane oxide compounds, and cyclosulfide resins may be used.

[Hardener] The light-shielding curable resin composition preferably contains a hardener. Examples of the hardener include compounds having phenolic hydroxyl groups, polycarboxylic acids and their anhydrides, compounds having cyanate groups, compounds having active ester groups, compounds having maleimide groups, alicyclic olefin polymers, etc. The hardener may be used alone or in combination of two or more.

Resins having phenolic hydroxyl groups may include phenol novolac resins, alkyl novolac resins, bisphenol A novolac resins, dicyclopentadiene-type phenol resins, Xylok-type phenol resins, terpene-modified phenol resins, cresol/naphthol resins, polyvinylphenols, phenol/naphthol resins, phenol resins containing an α-naphthol skeleton, cresol novolac resins containing a triazine skeleton, biphenyl aralkyl-type phenol resins, Zilog-type phenol novolac resins, and other conventionally known resins. Examples of the resin having a phenolic hydroxyl group include dicyclopentadiene skeleton phenol novolac resins (GDP series, manufactured by Qun-Ei Chemical Co., Ltd.), Zilog type phenol novolac resins (MEH-7800, manufactured by Meiwa Chemicals Co., Ltd.), biphenyl aralkyl type novolac resins (MEH-7851, manufactured by Meiwa Chemicals Co., Ltd.), naphthol aralkyl type hardeners (SN series, manufactured by NIPPON STEEL Chemical & Material Co., Ltd.), cresol novolac resins containing a triazine skeleton (LA-3018-50P, manufactured by DIC Corporation), and phenol novolac resins containing a triazine skeleton (LA-705N, manufactured by DIC Corporation).

The compound having a cyanate group is preferably a compound having two or more cyanate groups (-OCN) in one molecule. The compound having a cyanate group may be a conventionally known compound. Examples of the compound having a cyanate group include phenol novolac type cyanate resins, alkylphenol novolac type cyanate resins, dicyclopentadiene type cyanate resins, bisphenol A type cyanate resins, bisphenol F type cyanate resins, and bisphenol S type cyanate resins. In addition, the compound may be a partially triazine-treated prepolymer.

Commercially available compounds having a cyanate group include phenol novolac type multifunctional cyanate resin (PT30S manufactured by Lonza Japan Co., Ltd.), a prepolymer of a trimer in which part or all of bisphenol A dicyanate is triazine-modified (BA230S75 manufactured by Lonza Japan Co., Ltd.), and a cyanate resin containing a dicyclopentadiene structure (DT-4000, DT-7000 manufactured by Lonza Japan Co., Ltd.).

The compound having an active ester group is preferably a compound having two or more active ester groups in one molecule. The compound having an active ester group can generally be obtained by a condensation reaction of a carboxylic acid compound and a hydroxyl compound. Among them, the compound having an active ester group obtained by using a phenol compound or a naphthol compound as a hydroxyl compound is preferred. Examples of phenolic compounds or naphthol compounds 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, dicyclopentadienyldiphenol, phenol novolac, etc. In addition, the compound having an active ester group may be a naphthol alkyl/benzoic acid type.

Examples of commercially available compounds having an active ester group include dicyclopentadiene-type diphenol compounds, such as HPC8000-65T (manufactured by DIC Corporation), HPC8100-65T (manufactured by DIC Corporation), and HPC8150-65T (manufactured by DIC Corporation).

The compound having a maleimide group is a compound having a maleimide skeleton, and any of the conventionally known compounds can be used. The compound having a maleimide group preferably has two or more maleimide skeletons, and more preferably is N,N'-1,3-phenylene dimalienyl, N,N'-1,4-phenylene dimalienyl, N,N'-4,4-diphenylmethane dimaleimide, 1,2-bis(maleimide)ethane, 1,6-dimaleimidehexane, 1,6-dimaleimide-(2,2,4-trimethyl)hexane, 2,2'-bis-[4 [0013] The present invention relates to at least one of bis(4-maleimidephenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane dimaleimide, 4-methyl-1,3-phenylene dimaleimide, bis(3-ethyl-5-methyl-4-maleimidephenyl)methane, bisphenol A diphenyl ether dimaleimide, polyphenylmethane maleimide, and oligomers thereof, and diamine condensates having a maleimide skeleton. The oligomer is obtained by condensing a maleimide group-containing monomer of the above-mentioned compounds having a maleimide group.

Commercially available compounds having maleimide groups include BMI-1000 (4,4'-diphenylmethane bismaleimide, manufactured by Yamato Chemical Industries, Ltd.), BMI-2300 (phenylmethane bismaleimide, manufactured by Yamato Chemical Industries, Ltd.), BMI-3000 (m-phenylene bismaleimide, manufactured by Yamato Chemical Industries, Ltd.), BMI-5100 (3 ,3'-dimethyl-5,5'-dimethyl-4,4'-diphenylmethanebismaleimide, manufactured by Yamato Chemical Industries, Ltd.), BMI-7000 (4-methyl-1,3,-phenylenebismaleimide, manufactured by Yamato Chemical Industries, Ltd.), BMI-TMH ((1,6-bismaleimide-2,2,4-trimethyl)hexane, manufactured by Yamato Chemical Industries, Ltd.), etc.

The amount of hardener to be mixed is relative to 100 parts by mass of epoxy resin, preferably 20 to 500 parts by mass, and more preferably 25 to 500 parts by mass.

Hereinafter, an example will be described in which a light-shielding curable resin composition is formed from a thermosetting resin composition that does not contain a photocurable component, and components other than the above components may be contained.

The light-shielding curable resin composition 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 soluble in a solvent, the flexibility of the dry film can be improved, and the occurrence of cracking or powdering can be suppressed. Examples of the thermoplastic resin include thermoplastic polyhydroxy polyether resins or phenoxy resins of condensates of epichlorohydrin and various bifunctional phenol compounds, or phenoxy resins in which the hydroxyl groups present in the hydroxy ether portion of the skeleton are esterified using various acid anhydrides or acid chlorides, polyvinyl alcohol acetal resins, polyamide resins, polyamide imide resins, block copolymers, and the like. The thermoplastic resin may be used alone or in combination of two or more.

The amount of the thermoplastic resin blended is preferably 0.5 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total solid content of the light-shielding curable resin composition. When the amount of the thermoplastic resin blended is within the above range, a uniform roughened surface state can be easily obtained.

In addition, the light-shielding curable resin composition may contain rubber particles if necessary. Such rubber particles include polybutadiene rubber, polyisoprene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl-modified polybutadiene rubber, acrylonitrile-butadiene rubber modified with carboxyl or hydroxyl groups, and their cross-linked rubber particles, core-shell rubber particles, etc., and one type may be used alone or two or more types may be used in combination. Such rubber particles can improve the softness of the resulting cured film or improve the crack resistance, and can be added by surface roughening treatment with an oxidizing agent to improve the adhesion strength with copper foil, etc.

The average particle size of the rubber-like particles is preferably in the range of 0.005 to 1 μm, and more preferably in the range of 0.2 to 1 μm. The average particle size of the rubber-like particles can be obtained by a laser diffraction particle size distribution measuring device and a dynamic light scattering measuring device. The measuring device by the laser diffraction method can be Microtrac MT3300EXII manufactured by Microtrac-bel, and the measuring device by the dynamic light scattering method can be Nanotrac WaveII UT151 manufactured by Microtrac-bel.

The amount of rubber particles is preferably 0.5-10% by mass, and more preferably 1-5% by mass, based on the total solid content of the light-shielding curable resin composition. When the amount is 0.5% by mass or more, crack resistance can be obtained, and the adhesion strength with the conductor pattern can be improved. When the amount is less than 10% by mass, the coefficient of thermal expansion (CTE) decreases, the glass transition temperature (Tg) increases, and the curing characteristics are improved.

The light-shielding curable resin composition may contain a curing accelerator. The curing accelerator is used to accelerate the heat curing reaction in order to improve the properties such as adhesion, chemical resistance and heat resistance. Specific examples of such curing accelerators include imidazole and its derivatives; guanamines such as acetoguanamine and benzoguanamine; polyamines such as diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, cyanamide, urea, urea derivatives, melamine, polyhydrazine, etc.; organic acid salts and/or epoxy adducts thereof; amine complexes of boron trifluoride; ethyldiamino-S-triazine, 2- ,4-diamino-S-triazine, 2,4-diamino-6-xylyl-S-triazine and other triazine derivatives; trimethylamine, triethanolamine, N,N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa(N-methyl)melamine, 2,4,6-tris(dimethylaminophenol), tetramethylguanidine, m-aminophenol and other amines; polyvinylphenol, poly Polyphenols such as vinylphenol bromide, phenol novolac, alkylphenol novolac, etc.; organic phosphines such as tributylphosphine, triphenylphosphine, tri-2-cyanoethylphosphine, etc.; phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide, hexadecyltributylphosphonium chloride, etc.; quaternary ammonium salts such as benzyltrimethylammonium chloride, phenyltributylammonium chloride, etc.; the aforementioned polyacid anhydrides; diphenyl iodide The photocatalysts for the photopolymerization of tetrafluoroborate, triphenylphosphine hexafluoroantimonate, 2,4,6-triphenylthiopyrimidinium hexafluorophosphate, etc.; styrene-maleic anhydride resin; equimolar reactants of phenylisocyanate and dimethylamine, equimolar reactants of organic polyisocyanates such as methylphenyl diisocyanate and isophorone diisocyanate and dimethylamine, and metal catalysts are conventionally known hardening accelerators. Among the hardening accelerators, phosphonium salts are preferred for obtaining BHAST resistance.

The curing accelerator may be used alone or in combination of two or more. The use of a curing accelerator is not essential, but when the curing is to be accelerated, it is preferably used in an amount of 0.01 to 5 parts by mass relative to 100 parts by mass of the epoxy resin. In the case of a metal catalyst, the amount is preferably 10 to 550 ppm, more preferably 25 to 200 ppm, relative to 100 parts by mass of the compound having a cyanate group, in terms of metal.

The organic solvent is not particularly limited, and examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum-based solvents, and the like. Specifically, examples thereof include 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 monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; ethyl acetate, butyl acetate; , isobutyl acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate, etc.; alcohols such as ethanol, propanol, 2-methoxypropanol, n-butanol, isobutyl alcohol, isoamyl alcohol, ethylene glycol, propylene glycol, etc.; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc.; and N,N-dimethylformamide (DMF), tetrachloroethylene, turpentine, etc. In addition, organic solvents such as Swasol 1000 and Swasol 1500 manufactured by Maruzen Petrochemical Co., Ltd., solvent #100 and solvent #150 manufactured by Sankyo Chemical Co., Ltd., shellsol A100 and shellsol A150 manufactured by Shell Chemicals Japan Co., Ltd., and Ipsol No. 100 and Ipsol No. 150 manufactured by Idemitsu Kosan Co., Ltd. can be used. The organic solvent may be used alone or as a mixture of two or more.

The amount of residual solvent in the light-shielding curable resin composition is preferably 0.5 to 7.0 mass %. When the residual solvent is 7.0 mass % or less, sudden boiling during heat curing is suppressed, and the surface flatness becomes better. In addition, the melt viscosity can be suppressed from falling too low, the resin flows, and the flatness becomes better. When the residual solvent is 0.5 mass % or more, the fluidity during layering is good, and the flatness and embedding properties become better.

The light-shielding curable resin composition may contain, if necessary, conventionally known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, naphthalene black, etc., conventionally known thickeners such as asbestos, orben, bentonite, micro powdered silica, etc., defoaming agents and/or leveling agents such as polysilicone, fluorine, and polymer, adhesion imparting agents such as thiazole, triazole, and silane coupling agents, flame retardants, and conventionally known additives such as titanium esters and aluminum.

The thickness of the hardening resin layer of the dry film composed of the light-shielding hardening resin composition may be, for example, 1 to 200 μm. Within this thickness range, the maximum diameter of the aggregated particles of the inorganic filler in the light-shielding hardening resin composition is less than half the thickness of the hardening resin layer. When the thickness of the hardening resin layer is large, the flatness is better, so, for example, a thickness of 30 μm or more, 50 μm or more, and 100 μm or more may be more suitable for use. In addition, by stacking multiple hardening resin layers, a hardening resin layer with a thickness exceeding 200 μm may be formed. At this time, a roll laminator or a vacuum laminator may be used.

[Carrier film] The carrier film refers to a film that supports the curable resin layer of the dry film. When the curable resin layer is formed, a light-shielding curable resin composition is applied to the film. Examples of the carrier film include polyester films such as polyethylene terephthalate or polyethylene naphthalate, polyimide films, polyamide imide films, polyethylene films, polytetrafluoroethylene films, polypropylene films, polystyrene films, and surface-treated paper. Among these, polyester films are preferably used from the perspectives of heat resistance, mechanical strength, and usability. The thickness of the carrier film is not particularly limited, and is generally in the range of 10 to 150 μm, and can be appropriately selected according to the intended use. The surface of the carrier film on which the curable resin layer is provided may be subjected to a mold release treatment. Furthermore, the surface of the carrier film on which the curable resin layer is provided can also be sputter-plated or formed with an extremely thin copper foil.

[Protective film] The protective film is placed on the opposite side of the carrier film of the curable resin layer to prevent dust from adhering to the surface of the curable resin layer of the dry film and to improve usability. It is preferably a biaxially oriented polypropylene film (OPP) as the protective film. Since the biaxially oriented polypropylene film is used, the cooling shrinkage of the curable resin layer after lamination can be reduced. The protective film is not limited to biaxially oriented polypropylene film. The thickness of the protective film is not particularly limited and is generally in the range of 10 to 100 μm and can be appropriately selected according to the application. The surface of the protective film on which the curable resin layer is placed is preferably subjected to embossing, corona treatment, micro-adhesion treatment, or other treatments to improve adhesion or mold release.

The dry film of the present invention is laminated on a semiconductor wafer, etc., and the curable resin layer is cured to form a cured product, which is suitable for use in electronic parts, especially semiconductor devices, printed wiring boards, or the formation of permanent protective films for optical sensor modules. Among them, it is suitable for packaging materials for semiconductor chips. Using the dry film of the present invention, wiring boards can also be formed by bonding wiring.

The cured product of the light-shielding curable resin composition of the present invention, or the electronic parts using the cured product of the dry film of the present invention, for example, include semiconductor devices, printed wiring boards, or optical sensor modules. The manufacturing method of this electronic part can also use the method known in the past. Example

The following are examples and comparative examples of the present invention to specifically illustrate the present invention, but the present invention is not limited to these examples. In addition, the following "parts" and "%" are all based on mass unless otherwise stated.

<Preparation of light-shielding curable resin composition> Put the solvents of the examples and comparative examples in a container, heat to 50°C and stir to prevent the solvents from volatilizing, and then add the resin components and coupling agents respectively. After confirming that the resin components are dissolved, add the inorganic fillers and colorants described in the examples and stir thoroughly. Then, knead with a bead mill filled with zirconia beads to prepare a light-shielding curable resin composition. The bead mill uses a conical type K-8 (manufactured by Buehler) and kneads at a rotation speed of 1200 rpm, a discharge volume of 20%, a bead diameter of 0.65 mm, and a filling rate of 88%. In addition, the numerical values in the table, especially when there is no % description, represent the mass part, and except for the solvent, polymer resin and nano silica, represent the solid content.

<Dispersibility> The prepared light-shielding curable resin composition was confirmed for dispersion using a 0-50μm particle size meter according to the JIS K5600-2-5 dispersion method. The evaluation criteria are as follows. In addition, the maximum particle size of the agglomerated particles obtained using the particle size meter is shown in the table. ○: The dispersion determined by the 5-particle value is 20μm or less △: The dispersion determined by the 5-particle value exceeds 20μm and does not reach 30μm ×: The dispersion determined by the 5-particle value exceeds 30μm

<Inhibition of sedimentation of composition (ink)> The prepared light-shielding curable resin composition was placed in a transparent glass screw tube and stored in a constant temperature bath set at 23°C for 12 hours for aging. The light-shielding curable resin composition was poured from the bottom of the screw tube to 50 mm. After aging, the light-shielding curable resin composition was taken out and visually observed from the side to confirm the sedimentation state of the light-shielding curable resin composition. The judgment criteria are as follows. 0: No sedimentation was observed. △: A transparent supernatant less than 1 mm was confirmed from the upper part of the composition. ×: A transparent supernatant of more than 20 mm was confirmed from the upper part of the composition.

<Preparation of dry film> The amount of solvent in the prepared light-shielding curable resin composition was adjusted to a viscosity of 0.5~20dPa･s (rotational viscometer 5rpm, 25℃), and applied to a carrier film (PET film; TN-200 manufactured by Toyobo Co., Ltd., thickness 38μm, size 30cm×30cm) using a coating rod, and the film thickness of the curable resin layer was made to be 40μm after drying. Then, it was dried in a hot air circulation drying oven at 70~120℃ (average 100℃) for 5~10 minutes, so that the residual solvent in the curable resin layer was made to be 0.5~2.5% by mass, and a curable resin layer was formed on the carrier film. Next, a biaxially oriented polypropylene film (OPP, alphan FG-201, Fish Aires, ojif-tex) was laminated on the surface of the prepared dry film using a roll laminator set at 80°C to prepare a three-layer dry film.

<Transmittance> The protective film of the obtained 3-layer dry film was peeled off and pasted on a 1mm thick slide using a vacuum laminator MVLP-500 (produced by Meiki Seisakusho). The lamination temperature was 80~110℃ and the pressure was 0.5MPa. Then, after peeling off the carrier film, the resin layer was cured in a hot air circulation drying oven at 100℃×30min and 200℃×60min. The obtained cured product was measured for transmittance at 380nm~780nm using a UV-visible near-infrared spectrophotometer V-700 (produced by JASCO Corporation). The evaluation criteria are as follows. ◎: Transmittance is less than 0.1% in the full wavelength range ○: Transmittance is above 0.1% and below 0.5% in the full wavelength range ×: Transmittance is above 0.5% in the full wavelength range

<Cutting resistance> The protective film of the obtained 3-layer dry film was peeled off and pasted on an 8-inch silicon wafer with a thickness of 700μm using a vacuum laminator MVLP-500 (manufactured by Meiki Manufacturing). The conditions were lamination temperature 80~110℃ and pressure 0.5MPa. Then, after peeling off the carrier film, the resin layer was cured at 100℃×30min and 200℃×60min using a hot air circulation drying furnace. Then, the cutting machine DFD6240 (manufactured by DISCO, equipped with a ceramic blade) was used to evaluate the cutting resistance of the cured film. The cutting conditions were rotation number 10000rpm and conveying speed 1mm/min. The evaluation criteria are as follows. ◎: No burrs or resin defects on the surface of the cured film ○: The length of burrs or resin defects on the surface of the cured film is less than 1.0 mm ×: The length of burrs or resin defects on the surface of the cured film is more than 1.0 mm

<Warp of substrate> On a copper-laminated board with a copper thickness of 12μm and a board thickness of 0.1mm (MCL-E-770G, manufactured by Hitachi Chemical Co., Ltd., size 10×10cm), electroplated copper (Atotech Co., Ltd., surface roughness after electroplating is less than 100nm) was treated, and the total copper thickness was 20μm. Then, pre-treatment CZ-8101 (1μm etching, manufactured by MEC Co., Ltd.) was performed. Then, the dry film after peeling off the OPP was attached to one side of the substrate using a 2-chamber vacuum laminator CVP-600 (manufactured by Nichigo-Morton). The conditions were that the lamination and pressing were performed at a temperature of 80~110℃ and a pressure of 0.5MPa. Next, after peeling off the carrier film, the resin layer was hardened in a hot air circulation drying furnace at 100°C × 30min and 200°C × 60min. Then, the reflow treatment was performed for 5 cycles with a peak temperature of 280°C and an exposure time of 10 seconds or more at or above 275°C, and the warping state of the 4 corners of the substrate was measured with a vernier scale (the warping shape was a smile). The evaluation criteria are as follows. ◎: No warping ○: Among the 4 corners, the warping amount of the largest part of the warping is less than 10mm △: Among the 4 corners, the warping amount of the largest part of the warping is more than 10mm and less than 30mm ×: Among the 4 corners, the warping amount of the largest part of the warping is more than 30mm

Table 1 shows the mixing ratio of each component and the evaluation results.

Notes *1 to 17 in Table 1 are as follows. *1: jER828 manufactured by Mitsubishi Chemical, bisphenol A type epoxy resin, epoxy equivalent 189 g/eq, liquid *2: NC-3000H manufactured by Nippon Kayaku, biphenyl novolac type epoxy compound, epoxy equivalent 290 g/eq, *3: Primaset PT-30 manufactured by Lonza Japan, novolac type cyanate resin, cyanate equivalent 124 g/eq, solid *4: EPICLON manufactured by DIC HPC-8000, active ester resin, active equivalent 223g/eq, solid *5: HF-1M, phenol novolac resin, manufactured by Meiwa Chemicals *6: 2E4MZ, 2-ethyl-4-methylimidazole, manufactured by Shikoku Chemicals *7: Cobalt(II) acetylacetonate, manufactured by Tokyo Chemical Industry *8: Polymer resin with a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, Teisanresin SG-80H manufactured by Nagase Chemtex, MEK-free product, solid content 18% by mass, acrylic copolymer resin (functional groups: epoxy, amide) *9: Carbon black powder MA77 manufactured by Mitsubishi Chemical (average particle size 23nm) *10: Paliogen Red K 3580, Pigment Red 149, BASF, perylene-based colorant *11: Solvent Green 3, Tokyo Chemical Industry, green anthraquinone-based colorant *12: Fastogen blue 5380, DIC, phthalocyanine blue *13: Cromophtal (registered trademark) Red A2BN, BASF, red anthraquinone-based colorant *14: Denka, silica particles FB-3SDC (D50 = 3.1μm) *15: admatechs, silica particles SO-E1 (D50 = 0.2μm) *16: admatechs, nanosilica (D50 = 50nm), solid content 30 mass% *17: Shin-Etsu Chemical, epoxy silane coupling agent KBM-403

From the results shown in Table 1 above, it can be seen that the dry film having a curable resin layer composed of a light-shielding curable resin composition shown in each embodiment is excellent in dispersibility, ink sedimentation suppression, light transmission suppression (in other words, light-shielding property), cutting resistance, and substrate warping suppression.

11: Dry film 12: Curable resin layer 13: Carrier film 14: Protective film

[Figure 1] is a schematic cross-sectional view of one embodiment of the dry film of the present invention. [Figure 2] is a diagram showing the color of the colorant using the a* value and b* value in the L*a*b* color system as coordinate axes.

Claims (8)

A dry film characterized by having a curable resin layer composed of a light-shielding curable resin composition including a polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more, a coloring agent, and an inorganic filler. When the thickness of the curable resin layer is X (μm), the maximum particle size of the aggregated particles of the inorganic filler is less than X/2 (μm), and the polymer resin is an acrylic copolymer having a glass transition temperature of 20°C or less and a weight average molecular weight of 100,000 to 1,000,000. For example, in the dry film of claim 1, the maximum particle size of the agglomerated particles of the aforementioned inorganic filler is less than 10 μm. For example, in the dry film of claim 1, the amount of the inorganic filler is 0.1 to 70% by mass relative to the solid content of the light-shielding curable resin composition. For a dry film as in any one of claims 1 to 3, the amount of the aforementioned colorant is 0.3 to 20% by mass relative to the solid content of the aforementioned light-shielding curable resin composition. A dry film as in any one of claims 1 to 3, wherein the amount of the polymer resin having a glass transition temperature of 20°C or less and a weight average molecular weight of 10,000 or more is 1 to 35% by mass relative to the solid component of the light-shielding curable resin composition. In the dry film of any one of claims 1 to 3, the aforementioned hardening resin layer further comprises liquid epoxy resin. A hardened product characterized by being obtained by hardening the hardening resin layer of the dry film of any one of claims 1 to 6. An electronic component characterized by having a hardened material as described in claim 7.

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