Laminated solid, curable resin composition, dry film, and method for producing a laminated solid

Abstract

The present invention relates to a laminated cured body, a curable resin composition, a dry film, and a method for manufacturing a laminated cured body, and provides a cured product layer having both landfillability, insulation reliability, and resolution, a curable resin composition for the cured product layer, a dry film formed from the curable resin composition, and a method for manufacturing the cured product layer. The cured product layer may be, for example, a laminated cured body or the like, which is a laminated cured body in which a (A) first cured product layer formed from a first curable resin composition and a (B) second cured product layer formed from a negative second curable resin composition are sequentially laminated on a circuit board, and is characterized in that: the thickness of the (A) first cured product layer is thinner than the thickness of the connection circuit of the circuit board, the negative second curable resin composition contains an inorganic filler and an ultraviolet absorber, and the first curable resin composition does not contain an inorganic filler, or contains an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content conversion.

Description

Technical Field

[0001] The present invention relates to a laminated cured body, a curable resin composition, a dry film, and a method for manufacturing a laminated cured body. Background Art

[0002] Generally, in electronic components such as printed circuit boards, from the viewpoints of heat resistance and electrical insulation, a curable resin composition containing a curable resin such as a carboxyl group-containing resin and an epoxy resin as a main component and further containing additive components such as inorganic fillers is widely used for interlayer insulating material applications or solder resist material applications.

[0003] On the other hand, in response to the high density of printed circuit boards with the miniaturization, thinness, shortness, and small size of electronic devices, the miniaturization and multi-pinization of semiconductor packages have been put into practical use and mass production has been continuously promoted. Recently, semiconductor packages such as BGA (Ball Grid Array) and CSP (Chip Scale Package) using package substrates have been gradually adopted instead of semiconductor packages such as QFP (Quad Flat Package) and SOP (Small Outline Package). In such package substrates, wiring patterns are formed closer to each other with higher density. Therefore, for permanent films such as solder resist layers used in the corresponding package substrates, higher insulation reliability and resolution are gradually required.

[0004] As a curable composition capable of obtaining a cured film having excellent electrical insulation, for example, Patent Document 1 discloses a photocurable resin composition containing an acid-modified vinyl group-containing epoxy resin, an elastomer, a photopolymerization initiator, a diluent, and a curing agent as essential components.

[0005] Prior Art Documents

[0006] Patent Document 1: Japanese Patent Laid-Open No. 2002-303974 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] If an inorganic filler is added to the curable resin composition, generation of cracks due to CTE mismatch between the substrate and the wiring can be suppressed, and water absorption can be suppressed to improve HAST resistance. However, if the inorganic filler is highly filled, the melt viscosity increases, and the fillability of the gaps in the circuit, especially the gaps in fine pitch circuits, is insufficient. As a result, problems such as generation of voids and reduction of electrical reliability occur. For example, even the photosensitive resin composition disclosed in Patent Document 1 is not sufficient to form a cured material layer having both fillability, insulation reliability, and resolution.

[0009] Therefore, the object of the present invention is to provide a cured product layer having landfillability, insulation reliability, and resolution, a curable resin composition for the cured product layer, a dry film formed from the curable resin composition, and a method for manufacturing the cured product layer.

[0010] Solutions for Solving the Problems

[0011] The inventors of the present invention conducted in-depth research to achieve the above object, and as a result, found that by forming a laminated cured body having a specific laminated structure, the above problems can be solved, and thus the present invention was completed.

[0012] That is, the laminated cured body of the present invention is characterized in that it is a laminated cured body in which a (A) first cured product layer formed from a first curable resin composition and a (B) second cured product layer formed from a negative second curable resin composition are sequentially laminated on a circuit board. The thickness of the (A) first cured product layer is thinner than the thickness of the connection circuit of the circuit board. The negative second curable resin composition contains an inorganic filler and an ultraviolet absorber, and the first curable resin composition does not contain an inorganic filler or contains an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content.

[0013] The first curable resin composition of the present invention is characterized in that it is used as the first curable resin composition in the laminated cured body.

[0014] The second curable resin composition of the present invention is characterized in that it is used as the second curable resin composition in the laminated cured body.

[0015] The first dry film of the present invention is characterized in that it has a resin layer formed from the first curable resin composition.

[0016] The second dry film of the present invention is characterized in that it has a resin layer formed from the second curable resin composition.

[0017] The laminated cured body of the present invention is preferably a semiconductor package substrate.

[0018] The method for manufacturing the laminated cured body of the present invention is a method for manufacturing a laminated cured body in which a (A) first cured product layer formed from a first curable resin composition and a (B) second cured product layer formed from a negative second curable resin composition are sequentially laminated on a circuit board, and is characterized by including the following steps:

[0019] A step of forming a (A) first cured product layer on a circuit substrate, the (A) first cured product layer being formed from the first curable resin composition, and the first curable resin composition not containing an inorganic filler or containing an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content;

[0020] Step of forming a (B) second cured product layer on the (A) first cured product layer, the (B) second cured product layer being formed from the negative second curable resin composition, the negative second curable resin composition containing an inorganic filler and an ultraviolet absorber.

[0021] Effects of the Invention

[0022] According to the present invention, it is possible to provide a laminated cured body having a cured product layer with both landfillability, insulation reliability, and resolution, a curable resin composition for the laminated cured body, a dry film formed from the curable resin composition, and a method for manufacturing the laminated cured body. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic cross-sectional view showing a brief cross-section of an embodiment of the laminated cured body of the present invention and its manufacturing method.

[0024] Figure 2 It is a schematic cross-sectional view showing a brief cross-section of an embodiment of the laminated cured body of the present invention and its manufacturing method.

[0025] Figure 3 It is a schematic cross-sectional view showing a brief cross-section of an embodiment of the laminated cured body of the present invention.

[0026] Explanation of Reference Signs

[0027] 1 Substrate

[0028] 2a Connection circuit portion (pad) of the conductor circuit

[0029] 2b Wiring portion (line) of the conductor circuit

[0030] 3 Layer formed from the first curable resin composition ((A) first cured product layer)

[0031] 4 Layer formed from the second curable resin composition ((B) second cured product layer)

[0032] 5 Laminated cured body

[0033] 6 Solder bump

[0034] 7 Conductor portion

[0035] 8 Semiconductor chip

[0036] 9 Chip

[0037] 10 Laminated cured body with a chip mounted thereon

[0038] 11 Dam portion

[0039] 12 Chip-mounted laminated cured body

[0040] 13 Laminated conductor part

[0041] 14 Layer formed of curable resin composition (cured layer)

[0042] 15 Laminated cured body further laminated with cured layer Detailed implementation mode

[0043] The laminated cured body of the present invention is characterized in that it is a laminated cured body in which a (A) first cured layer formed of a first curable resin composition and a (B) second cured layer formed of a negative second curable resin composition are sequentially laminated on a circuit board. The thickness of the (A) first cured layer is thinner than the thickness of the connection circuit of the circuit board. The negative second curable resin composition contains an inorganic filler and an ultraviolet absorber. The first curable resin composition does not contain an inorganic filler, or contains an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content conversion.

[0044] In the present invention, by making the first curable resin composition used to form the (A) first cured layer on the circuit board side not contain an inorganic filler, or contain an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content conversion, the filling property can be ensured. On the other hand, by forming the (B) second cured layer on the opposite side of the substrate, that is, the surface layer side, from a negative second curable resin composition containing an inorganic filler and an ultraviolet absorber, and making the thickness of the (A) first cured layer thinner than the connection circuit, a laminated cured body with excellent resolution and insulation reliability can be formed. If the thickness of the (A) first cured layer is the same as the thickness of the connection circuit, cracks will occur at the interface between the (A) first cured layer and the (B) second cured layer (also called the connection circuit boundary), so good insulation reliability cannot be ensured. In addition, if the negative second curable resin composition does not contain an ultraviolet absorber, the resolution is insufficient.

[0045] The content of the inorganic filler in the first curable resin composition needs to be less than that of the negative second curable resin composition in terms of the solid content conversion ratio, and may not contain an inorganic filler, or may be, for example, 30% by mass or less, 25% by mass or less, 20% by mass or less as the upper limit. When the first curable resin composition contains an inorganic filler, the content of the inorganic filler in the first curable resin composition is preferably 5% by mass or more less, more preferably 10% by mass or more less, compared with the content of the inorganic filler in the negative second curable resin composition in terms of the solid content conversion. The larger the difference between the content of the inorganic filler in the first curable resin composition and the content of the inorganic filler in the second curable resin composition, the easier it is to achieve the balance between the landfillability and the insulation reliability.

[0046] In addition, since the first curable resin composition does not contain an inorganic filler or contains a small amount of an inorganic filler, from the viewpoint of crack resistance, as a stress relaxant, it is preferably contains a low modulus and high elongation material such as an elastomer and rubber particles.

[0047] The content of the inorganic filler in the second curable resin composition is not particularly limited, and preferably contains a large amount in consideration of the insulation reliability, that is, a cured product with a low water absorption rate. The content of the inorganic filler in the second curable resin composition can be set according to the use, and from the viewpoint of suppressing the HAST resistance due to the water absorption rate and the adhesion when filling a conductive material such as copper plating in the opening of the second cured product layer described later, it can be, for example, 20% by mass or more, 25% by mass or more, 30% by mass or more, 35% by mass or more as the lower limit. On the other hand, as the upper limit, considering the resolution, it can be, for example, 85% by mass or less, 80% by mass or less.

[0048] As described later, the inorganic filler is preferably surface-treated. In addition, the inorganic filler is not particularly limited, and may contain, for example, an exothermic filler such as alumina. From the viewpoint of the coefficient of thermal expansion value of the cured product, containing silica can improve the crack resistance, and thus is preferred.

[0049] Among the ultraviolet absorbers, especially by using a diazonaphthoquinone compound, the crosslinking density of the cured product can be improved, and the CTE of the cured product is not increased, which is also beneficial to the improvement of heat resistance. On the other hand, by adding an inorganic filler, a cured product having a low CTE and also having a solder resist function can be obtained.

[0050] In addition, when the second curable resin composition contains a colorant, it is possible to prevent defective detection during AOI (Automatic Optical Inspection Device) detection.

[0051] The second curable resin composition preferably contains a curing accelerator to improve the adhesion to the underfill.

[0052] (A) The method for adjusting the thickness of the first cured layer is not particularly limited. For example, as shown in Figure 1 (1), on the substrate 1 formed with a circuit, a curable resin composition for the first cured layer (i.e., the first curable resin composition) is coated and dried, or a resin layer is laminated in the form of a dry film to form a layer 3 formed of the first curable resin composition. Thereafter, an etching process can be performed by a known method such as wet etching (alkali aqueous solution) or dry etching (plasma). As shown in Figure 1 (2), the thickness of (A) the first cured layer is adjusted to be thinner than the thickness of the connection circuit 2a.

[0053] Thereafter, before or after the layer 3 formed of the first curable resin composition is cured, a curable resin composition for the second cured layer (i.e., a negative second curable resin composition) is coated on the layer 3 formed of the first curable resin composition and dried, or after laminating a resin layer in the form of a dry film, it is exposed and developed. As shown in Figure 1 (3), a layer 4 formed of the negative second curable resin composition constituting the fine pattern can be formed. Although the layer 3 formed of the first curable resin composition can be formally cured before the layer 4 formed of the negative second curable resin composition is formed, simultaneous formal curing with the layer 4 formed of the negative second curable resin composition can make (A) the first cured layer and (B) the second cured layer more closely adhered, so it is more preferable from the viewpoint of insulation reliability.

[0054] The laminated cured body of the present invention can be preferably used for electronic devices. When the laminated cured body of the present invention is an encapsulation substrate, for example, a chip 9 shown in Figure 1 (4) can be mounted as shown in Figure 1 (5).

[0055] In addition, in the present invention, not only locally making the thickness thinner than the connection circuit as in (A) the first cured layer shown in Figure 1 , but also making the overall thickness thinner than the connection circuit as shown in Figure 2 . In Figure 2 , as shown in Figure 2 (1), after forming the layer 3 formed of the first curable resin composition, through wet etching or the like, as shown in Figure 2 (2), the thickness of the layer 3 formed of the first curable resin composition is adjusted to be thinner than the connection circuit 2a as a whole. In addition, as shown in Figure 2 (3), on the layer 4 formed of the second curable resin composition, a pattern can also be formed at a place other than above the connection circuit 2a. For example, as shown in Figure 2 (4), on the laminated cured body 12 on which the chip is mounted, a dam 11 for underfill stop flow can also be formed.

[0056] Other layers can be further laminated on the laminated structure of the present invention. For example, by using known conventional methods such as electroless plating, electroplating, and conductive paste, as Figure 3 shown, after laminating the conductor portion 13 on the connection circuit, a curable resin composition (not particularly limited, for example, a negative-type second curable resin composition) is coated and dried, or after laminating its dry film, it is exposed and developed to form a layer 14 formed of a curable resin composition that constitutes a fine pattern. In the present invention, when forming a structure in which a conductive material such as copper plating is filled in the opening of the second cured layer, by highly filling an inorganic filler in the second cured layer, the CTE mismatch of the conductive material is suppressed, and the adhesion of the conductive material becomes good. The number of laminated layers as described above is not particularly limited, and further lamination can be performed within a possible range.

[0057] In the present invention, (A) the thickness of the first cured layer may be thinner than that of the connection circuit. For example, when the thickness of the connection circuit is set to 100%, it may be 1 to 70% thinner than that. From the perspective of insulation reliability, the lower limit of the thinning treatment is preferably 2% or more, more preferably 3% or more, and further most preferably 5% or more thinner. From the perspective of (B) the fillability of the second cured layer, the upper limit is preferably 70% or less, more preferably 30% or less. That is, it is preferable that (A) the thickness of the first cured layer remains 30% or more of the thickness of the connection circuit, more preferably 70% or more.

[0058] In the present invention, (A) the first cured layer and (B) the second cured layer are cured products of a first curable resin composition and a negative-type second curable resin composition, respectively. The first curable resin composition and the negative-type second curable resin composition (hereinafter also simply referred to as "the first and second curable resin compositions") are not particularly limited, and known conventional curable resin compositions can be used.

[0059] For the first curable resin composition, in order to obtain fillability (fluidity) and adhesion to the circuit board, the melt viscosity of the composition at 90 °C is preferably 50 to 1000 dPa·s. To achieve this melt viscosity, it is preferable to contain an epoxy resin with a low softening point or a low epoxy equivalent, and more preferably to contain an epoxy resin with a softening point of 60 °C or lower or an epoxy equivalent of 200 g / eq. or lower.

[0060] Hereinafter, the components that the first and second curable resin compositions may contain will be further described in detail. It should be noted that in this specification, (meth)acrylate is a term that collectively refers to acrylate, methacrylate, and their mixtures, and the same applies to other similar expressions.

[0061] (Inorganic filler)

[0062] The inorganic filler is not particularly limited, and known and conventional inorganic fillers can be used, such as amorphous silica, crystalline silica, fused silica, spherical silica and other silicas, Noyanburg silica, aluminum hydroxide, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica, alumina, barium sulfate, barium titanate, iron oxide, non-fibrous glass, hydrotalcite, mineral wool, aluminum silicate, calcium silicate, zinc flower and other inorganic fillers. Among them, due to its low specific gravity, it can be highly filled in the cured product and is easy to strengthen, and from the perspective of the insulation reliability of the laminated cured body, silica is preferred.

[0063] The inorganic filler is preferably a surface-treated inorganic filler (also referred to as "surface-treated inorganic filler"), and more preferably a surface treatment capable of introducing a curable reactive group is applied to the surface of the inorganic filler. Here, the curable reactive group is not particularly limited as long as it is a group that undergoes a curing reaction with a curable compound such as an alkali-soluble resin or a thermosetting resin, and can be a photocurable reactive group or a thermosetting reactive group. Examples of the photocurable reactive group include methacryloyl group, acryloyl group, vinyl group, styryl group, etc., and examples of the thermosetting reactive group include epoxy group, amino group, hydroxyl group, carboxyl group, isocyanate group, imino group, oxetanyl group, mercapto group, methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, oxazoline group, etc. The method of introducing a curable reactive group to the surface of the inorganic filler is not particularly limited, and a known and conventional method can be used for introduction. A surface treatment agent having a curable reactive group can be used, for example, the surface of the inorganic filler can be treated with a coupling agent having a curable reactive group as an organic group. As the coupling agent, a silane coupling agent, a titanium coupling agent, a zirconium coupling agent, an aluminum coupling agent, etc. can be used. In addition, examples of the surface-treated inorganic filler without a curable reactive group include inorganic fillers surface-treated with silica-alumina, titanate-based coupling agents, aluminate-based coupling agents, and organic treatments.

[0064] In addition, when the inorganic filler contained in the (A) first cured product layer contains a material with a positive ZETA potential, the adhesion to the circuit board can be improved.

[0065] The average particle size of the inorganic filler is preferably 1 μm or less. In addition, it is preferably smaller than the exposure wavelength, and more preferably 0.3 μm or less. On the other hand, from the perspective of suppressing halation and aggregation during exposure, it is preferably 0.02 μm or more. Here, in this specification, the average particle size of the inorganic filler refers not only to the particle size of the primary particles, but also to the average particle size (D50) including the particle size of the secondary particles (aggregates), and is the D50 value measured by the laser diffraction method. Examples of the measuring device based on the laser diffraction method include Microtrac MT3300EXII manufactured by Microtrac Inc.

[0066] The average particle diameter of the inorganic filler can be adjusted. For example, it is preferably pre-dispersed using a bead mill or a jet mill. In addition, the inorganic filler is preferably compounded in a slurry state. By compounding in a slurry state, it is easy to achieve high dispersion, prevent aggregation, and is easy to operate.

[0067] The inorganic filler can be used alone or in combination of two or more kinds.

[0068] The first curable resin composition does not contain an inorganic filler, or, when containing an inorganic filler, the compounding amount of the inorganic filler in the solid component is less than that of the negative-type second curable resin composition. When containing an inorganic filler, although not particularly limited, in order to contain it in the (A) first cured product layer in the above content, as an upper limit, in the total amount of the solid components of the composition, for example, it is 30% by mass or less, 25% by mass or less. In addition, when containing an inorganic filler, the content of the inorganic filler is preferably 5% by mass or more less, more preferably 10% by mass or more less, than the content of the inorganic filler in the total amount of the solid components of the negative-type second curable resin composition.

[0069] The compounding amount of the inorganic filler in the second curable resin composition is not particularly limited, but in order to contain it in the (B) second cured product layer in the above content, as a lower limit, in the total amount of the solid components of the composition, for example, it is 20% by mass or more, 25% by mass or more, 30% by mass or more. On the other hand, as an upper limit, considering the resolution, for example, it is 85% by mass or less, 80% by mass or less.

[0070] (Ultraviolet absorber)

[0071] In the present invention, as the ultraviolet absorber, a diazonaphthoquinone compound is preferably contained. If a diazonaphthoquinone compound is contained, the effect of suppressing halation can be obtained with a smaller amount. In addition, since the diazonaphthoquinone compound decomposes to generate carboxylic acid during curing, by using the diazonaphthoquinone compound as the ultraviolet absorber, the crosslinking density of the cured product can be increased, the CTE of the cured product is not increased, and it is also beneficial to the improvement of heat resistance. As the diazonaphthoquinone compound, specifically, for example, naphthoquinone diazide adduct of tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene (such as TS533, TS567, TS583, TS593 manufactured by Mitsuhisa Chemical Research Institute), naphthoquinone diazide adduct of tetrahydroxybenzophenone (such as BS550, BS570, BS599 manufactured by Mitsuhisa Chemical Research Institute), naphthoquinone diazide adduct of 4-{4-[1,1-bis(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl}phenol (such as TKF-428, TKF-528 manufactured by Mitsuhisa Chemical Research Institute), etc. can be used.

[0072] In the present invention, substances other than diazonaphthoquinone compounds can also be used together as ultraviolet absorbers. Examples of such ultraviolet absorbers include inorganic ultraviolet absorbers such as carbon black and black titanium oxide (also known as titanium black), and organic ultraviolet absorbers.

[0073] Examples of organic ultraviolet absorbers include benzophenone derivatives, benzoate derivatives, benzotriazole derivatives, triazine derivatives, benzothiazole derivatives, cinnamate derivatives, anthranilate derivatives, dibenzoylmethane derivatives, etc. Specific examples of benzophenone derivatives include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, and 2,4-dihydroxybenzophenone. Specific examples of benzoate derivatives include 2-ethylhexyl salicylate, phenyl salicylate, p-tert-butylphenyl salicylate, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, and cetyl 3,5-di-tert-butyl-4-hydroxybenzoate. Specific examples of benzotriazole derivatives include 2-(2'-hydroxy-5'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, and 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole. Specific examples of triazine derivatives include hydroxyphenyltriazine, bis-ethylhexyloxyphenol methoxyphenyltriazine, etc.

[0074] As the ultraviolet absorber (I), commercially available products can also be used. For example, TINUVIN PS, TINUVIN 99-2, TINUVIN 109, TINUVIN 384-2, TINUVIN 900, TINUVIN 928, TINUVIN 1130, TINUVIN 400, TINUVIN 405, TINUVIN 460, TINUVIN 479 (manufactured by Ciba Specialty Chemicals Inc., trade names) etc. can be cited.

[0075] In the present invention, as the ultraviolet absorber other than the diazonaphthoquinone compound, an organic ultraviolet absorber is preferably contained. As the ultraviolet absorber, by using the diazonaphthoquinone compound and the organic ultraviolet absorber together as the ultraviolet absorber, the resolution can be further improved, and thus it is preferred.

[0076] The content of the ultraviolet absorber is preferably controlled to be 0.01 to 10% by mass based on the total amount of the resin solid components of the second curable resin composition. By making the content of the ultraviolet absorber 0.01% by mass or more, the halation suppression effect can be reliably obtained. On the other hand, by making the content of the ultraviolet absorber 10% by mass or less, deep curability can be obtained. More preferably, the compounding amount of the (D) ultraviolet absorber is 0.05 to 5% by mass based on the total amount of the resin solid components of the composition. In addition, when a plurality of ultraviolet absorbers are used in combination, the content of the diazonaphthoquinone compound is preferably 0.05 to 5% by mass. It should be noted that the total amount of the resin solid components of the second curable resin composition refers to the amount obtained by removing the content of the inorganic filler from the total amount of the solid components of the composition.

[0077] (Curable resin)

[0078] The curable resin is a thermosetting resin or a photocurable resin, or a mixture thereof. The compounding amounts of the curable resins in the first and second curable resin compositions are, for example, 1 to 80% by mass based on the total amount of the solid components of the composition, and can be appropriately adjusted according to the compounding amount of the inorganic filler in each composition.

[0079] (Thermosetting resin)

[0080] When a thermosetting resin is contained, the heat resistance of the cured product is improved, and in addition, the adhesion to the substrate is improved. As the thermosetting resin, known and conventional thermosetting resins such as isocyanate compounds, blocked isocyanate compounds, amino resins, benzoxazine resins, carbodiimide resins, cyclic carbonate compounds, epoxy compounds, polyfunctional oxetane compounds, and cyclic sulfur resins can be used. Among them, epoxy compounds, polyfunctional oxetane compounds, and compounds having two or more thioether groups in the molecule, i.e., cyclic sulfur resins, are preferred, and epoxy compounds are more preferred. The thermosetting resin can be used alone or in combination of two or more.

[0081] The above-mentioned epoxy compound is a compound having an epoxy group, and existing well-known products can be used. Polyfunctional epoxy compounds having a plurality of epoxy groups in the molecule can be cited. In addition, it can also be a hydrogenated epoxy compound.

[0082] Examples of the polyfunctional epoxy compounds include, but are not limited to, epoxidized vegetable oils; bisphenol A type epoxy resins; hydroquinone type epoxy resins; bisphenol type epoxy resins; thioether type epoxy resins; brominated epoxy resins; novolak type epoxy resins; bisphenol novolak type epoxy resins; bisphenol F type epoxy resins; hydrogenated bisphenol A type epoxy resins; glycidylamine type epoxy resins; hydantoin type epoxy resins; alicyclic epoxy resins; triphenylolmethane type epoxy resins; xylenol type or bisphenol type epoxy resins or mixtures thereof; bisphenol S type epoxy resins; bisphenol A novolak type epoxy resins; tetraphenylethane type epoxy resins; heterocyclic epoxy resins; diglycidyl phthalate resins; tetraglycidyl dimethylphenol ethane resins; naphthalene group-containing epoxy resins; epoxy resins having a dicyclopentadiene skeleton; glycidyl methacrylate copolymer type epoxy resins; copolymer epoxy resins of cyclohexyl maleimide and glycidyl methacrylate; epoxy-modified polybutadiene rubber derivatives; CTBN-modified epoxy resins, etc. These epoxy resins may be used alone or in combination of two or more kinds.

[0083] Examples of the polyfunctional oxetane compounds include, for example, bis[(3-methyl-3-oxetanylmethoxy)methyl] ether, bis[(3-ethyl-3-oxetanylmethoxy)methyl] ether, 1,4-bis[(3-methyl-3-oxetanylmethoxy)methyl] benzene, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate, oligomers or copolymers thereof and other polyfunctional oxetanes, and ether compounds of oxetane alcohols and resins having hydroxyl groups such as novolak resins, poly(p-hydroxystyrene), Cardo type bisphenols, calixarenes, resorcinol calixarenes, or silsesquioxanes. In addition, copolymers of unsaturated monomers having an oxetane ring and (meth)acrylic acid alkyl esters, etc. may also be mentioned.

[0084] Examples of the compounds having a plurality of cyclic thioether groups in the molecule include bisphenol A type cyclic sulfur resins and the like. In addition, cyclic sulfur resins obtained by replacing the oxygen atom of the epoxy group of novolak type epoxy resins with a sulfur atom by the same synthesis method may also be used.

[0085] Examples of the amino resins such as melamine derivatives and benzoguanamine derivatives include hydroxymethyl melamine compounds, hydroxymethyl benzoguanamine compounds, hydroxymethyl glycoluril compounds, and hydroxymethyl urea compounds.

[0086] As the isocyanate compound, a polyisocyanate compound can be blended. Examples of the polyisocyanate compound include aromatic polyisocyanates such as 4,4'-diphenylmethane diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, naphthalene-1,5-diisocyanate, o-xylene diisocyanate, m-xylene diisocyanate, and 2,4-toluene diisocyanate dimer; aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), and isophorone diisocyanate; alicyclic polyisocyanates such as bicycloheptane triisocyanate; and adducts, biurets, and isocyanurates of the above-listed isocyanate compounds.

[0087] As the blocked isocyanate compound, a by-product of the addition reaction of an isocyanate compound and an isocyanate blocking agent can be used. Examples of the isocyanate compound obtained by reacting with the isocyanate blocking agent include the above-listed polyisocyanate compounds. Examples of the isocyanate blocking agent include phenolic blocking agents; lactam blocking agents; active methylene blocking agents; alcohol blocking agents; oxime blocking agents; thiol blocking agents; acid amide blocking agents; imide blocking agents; amine blocking agents; imidazole blocking agents; imine blocking agents, etc.

[0088] (Photocurable resin)

[0089] As the photocurable resin, any resin that is cured by irradiation with active energy rays and exhibits electrical insulation can be used, and a compound having one or more ethylenically unsaturated groups in the molecule is preferably used. As the compound having an ethylenically unsaturated group, known and conventional photosensitive monomers such as photopolymerizable oligomers and photopolymerizable vinyl monomers can be used, and they can also be free-radical polymerizable monomers or cationic polymerizable monomers. In addition, as the photocurable resin, polymers such as carboxyl group-containing resins having an ethylenically unsaturated group as described later can be used. The photocurable resin can be used alone or in combination of two or more.

[0090] As the photosensitive monomer, a photosensitive (meth)acrylate compound having one or more (meth)acryloyl groups in the molecule and being liquid, solid, or semi-solid at room temperature can be used. The photosensitive (meth)acrylate compound that is liquid at room temperature can be used not only to improve the photoreactivity of the composition but also to adjust the viscosity of the composition to be suitable for various coating methods and to contribute to the solubility in an aqueous alkali solution.

[0091] Examples of the photopolymerizable oligomer include unsaturated polyester oligomers, (meth)acrylate oligomers, etc. Examples of the (meth)acrylate oligomers include epoxy (meth)acrylates such as phenol novolac epoxy (meth)acrylate, cresol novolac epoxy (meth)acrylate, and bisphenol type epoxy (meth)acrylate; urethane (meth)acrylate, epoxy urethane (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polybutadiene-modified (meth)acrylate, etc.

[0092] Examples of the photopolymerizable vinyl monomer may be well-known conventional monomers, and include, for example, styrene derivatives such as styrene, chlorostyrene, and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate, or vinyl benzoate; vinyl ethers such as vinyl isobutyl ether, vinyl-n-butyl ether, vinyl-t-butyl ether, vinyl-n-pentyl ether, vinyl isopentyl 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-methoxymethylacrylamide, N-ethoxymethylacrylamide, and N-butoxymethylacrylamide; 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, and phenoxyethyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-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, and dipentaerythritol hexa(meth)acrylate; polyalkylene 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 hydroxypivalic acid neopentyl glycol ester di(meth)acrylate; isocyanurate type poly(meth)acrylates such as tris[(meth)acryloyloxyethyl] isocyanurate, etc.

[0093] (alkali-soluble resin)

[0094] Examples of the alkali-soluble resin include compounds having two or more phenolic hydroxyl groups, carboxyl group-containing resins, compounds having a phenolic hydroxyl group and a carboxyl group, and compounds having two or more mercapto groups. Among them, when the alkali-soluble resin is a carboxyl group-containing resin or a phenol resin, the adhesion to the circuit board can be improved, and thus it is preferred. In particular, since the developability is excellent, the alkali-soluble resin is more preferably a carboxyl group-containing resin. The carboxyl group-containing resin may be a carboxyl group-containing photosensitive resin having an ethylenically unsaturated group or a carboxyl group-containing resin not having an ethylenically unsaturated group. The alkali-soluble resin may be used alone or in combination of two or more.

[0095] Specific examples of the carboxyl group-containing resin include the compounds exemplified below (which may be either an oligomer or a polymer).

[0096] (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 (meth)acrylic acid alkyl ester, or isobutylene.

[0097] (2) A carboxyl group-containing polyurethane resin obtained by subjecting a diisocyanate such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate, or an aromatic diisocyanate to an addition polymerization reaction with a carboxyl group-containing diol compound such as dimethylolpropionic acid or dimethylolbutanoic 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-based polyol, a bisphenol A-based epoxy alkane adduct diol, or a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

[0098] (3) A terminal carboxyl group-containing polyurethane resin obtained by reacting the terminal of a polyurethane resin obtained by subjecting a diisocyanate compound such as an aliphatic diisocyanate, a branched aliphatic diisocyanate, an alicyclic diisocyanate, or an aromatic diisocyanate to an addition polymerization reaction with a diol compound such as a polycarbonate-based polyol, a polyether-based polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic-based polyol, a bisphenol A-based epoxy alkane adduct diol, or a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group with an acid anhydride.

[0099] (4) A carboxyl group-containing polyurethane resin obtained by subjecting a diisocyanate to an addition polymerization reaction with a (meth)acrylate or a partial acid anhydride-modified product thereof of a bifunctional epoxy resin such as bisphenol A-type epoxy resin, hydrogenated bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, xylenol-type epoxy resin, or bisphenol-type epoxy resin, a carboxyl group-containing diol compound, and a diol compound.

[0100] (5) In the resin synthesis of (2) or (4) above, a carboxyl group-containing polyurethane resin with terminal (meth)acrylation is obtained by adding a compound having one hydroxyl group and one or more (meth)acryloyl groups in the molecule, such as hydroxyalkyl (meth)acrylate.

[0101] (6) In the resin synthesis of (2) or (4) above, a carboxyl group-containing polyurethane resin with terminal (meth)acrylation is obtained by adding an equimolar reactant of isophorone diisocyanate and pentaerythritol triacrylate, etc., a compound having one isocyanate group and one or more (meth)acryloyl groups in the molecule.

[0102] (7) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding a dibasic anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. to the hydroxyl groups present on the side chain.

[0103] (8) A carboxyl group-containing resin obtained by reacting a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of a bifunctional epoxy resin with epichlorohydrin with (meth)acrylic acid and adding a dibasic anhydride to the generated hydroxyl groups.

[0104] (9) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid and adding a dibasic anhydride to the generated primary hydroxyl groups.

[0105] (10) A carboxyl group-containing resin obtained by reacting a compound having multiple phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide and propylene oxide to obtain a reaction by-product, reacting the reaction by-product with a monocarboxylic acid containing an unsaturated group, and then reacting the obtained reaction by-product with a polybasic anhydride.

[0106] (11) A carboxyl group-containing resin obtained by reacting a compound having multiple phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate and propylene carbonate to obtain a reaction by-product, reacting the reaction by-product with a monocarboxylic acid containing an unsaturated group, and then reacting the obtained reaction by-product with a polybasic anhydride.

[0107] (12) A carboxyl group-containing resin obtained by reacting an epoxy compound having multiple epoxy groups in one molecule with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, such as p-hydroxyphenylethanol, and a monocarboxylic acid containing an unsaturated group such as (meth)acrylic acid, and then reacting the alcoholic hydroxyl groups of the obtained reaction by-product with a polybasic anhydride such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic dianhydride, adipic anhydride, etc.

[0108] (13) A carboxyl group-containing resin having at least one of an amide structure and an imide structure.

[0109] A carboxyl group-containing resin obtained by further adding a compound having one epoxy group and one or more (meth)acryloyl groups in a molecule, such as glycidyl (meth)acrylate and α-methylglycidyl (meth)acrylate, to the carboxyl group-containing resin described in the above (1) to (13) etc.

[0110] Examples of the compound having a phenolic hydroxyl group include compounds having a biphenyl skeleton or a phenylene skeleton or both skeletons, and phenolic resins having various skeletons synthesized from phenol, o-cresol, p-cresol, m-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, catechol, resorcinol, hydroquinone, methylhydroquinone, 2,6-dimethylhydroquinone, trimethylhydroquinone, pyrogallol, phloroglucinol, etc.

[0111] In addition, examples of the compound having a phenolic hydroxyl group include known conventional phenolic resins such as phenol novolak resin, alkylphenol borate resin, bisphenol A novolak resin, dicyclopentadiene type phenolic resin, Xylok type phenolic resin, terpene-modified phenolic resin, polyvinylphenols, bisphenol F, bisphenol S type phenolic resin, poly-p-hydroxystyrene, condensates of naphthol and aldehydes, condensates of dihydroxynaphthalene and aldehydes, etc.

[0112] The acid value of the alkali-soluble resin is preferably in the range of 40 to 200 mgKOH / g, more preferably in the range of 45 to 120 mgKOH / g. When the acid value of the alkali-soluble resin is 40 mgKOH / g or more, it is easily alkali-developable; on the other hand, when it is 200 mgKOH / g or less, it is easy to draw a normal cured product pattern, so it is preferred.

[0113] Although the weight average molecular weight of the alkali-soluble resin varies depending on the resin skeleton, it is preferably in the range of 1,500 to 150,000, and further preferably in the range of 1,500 to 100,000. When the weight average molecular weight is 1,500 or more, the non-tacky property is good, the moisture resistance of the exposed film is good, the film reduction during development can be suppressed, and the resolution decrease can be suppressed. On the other hand, when the weight average molecular weight is 150,000 or less, the developability is good and the storage stability is also excellent.

[0114] The compounding amounts of the alkali-soluble resins in the first and second curable resin compositions are, for example, 5 to 50% by mass based on the total solid content of the composition, respectively.

[0115] (Photoinitiator)

[0116] The first curable resin composition may contain a photoinitiator, and the negative second curable resin composition contains a photoinitiator as an essential component. The photoinitiator may be any product that can cure the composition by light irradiation, and is preferably any one of a photopolymerization initiator that generates free radicals by light irradiation and a photo-base generator that generates a base by light irradiation. In addition, the photoinitiator may of course also be a compound that generates both free radicals and a base by light irradiation. Light irradiation means irradiation with actinic rays having a wavelength in the range of 350 to 450 nm.

[0117] Examples of the photoinitiator include bisacylphosphine oxides such as bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; monoacylphosphine oxides such as 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, methyl 2,4,6-trimethylbenzoylphenylphosphinate, 2-methylbenzoyldiphenylphosphine oxide, isopropyl neopentanoyl phenylphosphinate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; hydroxyacetophenones such as 1-hydroxy-cyclohexyl phenyl 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, 2-hydroxy-2-methyl-1-phenylpropan-1-one; benzoins such as benzoin, benzyl, methyl benzoin ether, ethyl benzoin ether, n-propyl benzoin ether, isopropyl benzoin ether, n-butyl benzoin ether; benzoin alkyl ethers; benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methyl benzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholin-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, N,N-dimethylaminoacetophenone; thioxanthones such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; anthraquinones such as anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone; ketals such as acetophenone dimethyl ketal, benzyl dimethyl ketal; benzoates such as ethyl 4-dimethylaminobenzoate, 2-(dimethylamino)ethyl benzoate, ethyl p-dimethylbenzoate;1,2 - octanedione, 1 - [4 - (phenylthio)-, 2 - (O - benzoyl oxime)], acetone, 1 - [9 - ethyl - 6 - (2 - methylbenzoyl)-9H - carbazol - 3 - yl]-, 1 - (O - acetyl oxime) and other oxime esters; bis(η5 - 2,4 - cyclopentadien - 1 - yl)-bis(2,6 - difluoro - 3 - (1H - pyrrol - 1 - yl)phenyl)titanium, bis(cyclopentadienyl)-bis[2,6 - difluoro - 3 - (2 - (1 - pyridin - 1 - yl)ethyl)phenyl]titanium and other metallocene titaniums; phenyl disulfide, 2 - nitrofluorene, butyl ester, anisole, azobisisobutyronitrile, tetramethylthiuram disulfide, etc. The photoinitiator can be used alone or in combination of two or more kinds.

[0118] A photo base generator is a compound whose molecular structure changes or molecules are cleaved by light irradiation such as ultraviolet light and visible light, thereby generating one or more basic substances that can act as catalysts for thermosetting reactions. As the basic substances, secondary amines and tertiary amines can be cited, for example.

[0119] As the photo base generator, α - aminophenylacetone compounds, oxime ester compounds, acyloxyimino compounds, N - formylated aromatic amino compounds, N - acylated aromatic amino compounds, nitrobenzyl carbamate compounds, alkoxybenzyl carbamate compounds, etc. can be cited, for example. Among them, oxime ester compounds and α - aminophenylacetone compounds are preferred, oxime ester compounds are more preferred, and acetone, 1 - [9 - ethyl - 6 - (2 - methylbenzoyl)-9H - carbazol - 3 - yl]-, 1 - (O - acetyl oxime) is even more preferred. As the α - aminophenylacetone compound, products having two or more nitrogen atoms are particularly preferred. The photo base generator can be used alone or in combination of two or more kinds. In addition, quaternary ammonium salts, etc. can be cited as the photo base generator.

[0120] As other photo base generators, WPBG - 018 (trade name: 9 - anthrylmethyl N,N’ - diethylcarbamate), WPBG - 027 (trade name: (E)-1 - [3 - (2 - hydroxyphenyl)-2 - propenoyl]piperidine), WPBG - 082 (trade name: guanidinium 2 - (3 - benzoylphenyl)propionate), WPBG - 140 (trade name: 1 - (anthraquinon - 2 - yl)ethylimidazolecarboxylate), etc. manufactured by Fujifilm Wako Pure Chemical Corporation can also be used.

[0121] In addition, a part of the photoinitiator can also function as a photo-base generator. As the photoinitiator that can also function as a photo-base generator, oxime ester photoinitiators and α-aminoacetophenone photoinitiators are preferred.

[0122] The compounding amounts of the photoinitiators of the first and second curable resin compositions are respectively, for example, 0.01 to 30% by mass based on the total solid content of the composition.

[0123] (Curing accelerator)

[0124] The first and second curable resin compositions may contain a curing accelerator. Examples of the curing accelerator include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; amine compounds such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine, 4-dimethylaminopyridine; hydrazine compounds such as adipic dihydrazide; phosphorus compounds such as triphenylphosphine. In addition, guanamine, acetylguanamine, phenylguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine·isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine·isocyanuric acid adduct and other S-triazine derivatives can also be used. In addition, metal curing accelerators can also be used, and examples include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organometallic complexes include organocobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organocopper complexes such as copper(II) acetylacetonate, organozinc complexes such as zinc(II) acetylacetonate, organoiron complexes such as iron(III) acetylacetonate, organonickel complexes such as nickel(II) acetylacetonate, and organomanganese complexes such as manganese(II) acetylacetonate. Examples of the organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, zinc stearate. As the curing accelerator, it is preferred to use these compounds that can also function as adhesion improvers in combination with the curing accelerator. The curing accelerator can be used alone or in combination of two or more.

[0125] The compounding amounts of the curing accelerators of the first and second curable resin compositions are respectively, for example, 0.01 to 30% by mass based on the total solid content of the composition.

[0126] (Curing agent)

[0127] The first and second curable resin compositions may contain a curing agent. Examples of the curing agent include compounds having a phenolic hydroxyl group, polycarboxylic acids and their acid anhydrides, compounds having a cyanate ester group, compounds having a maleimide group, alicyclic olefin polymers, etc. The curing agent may be used alone or in combination of two or more.

[0128] As the compound having a phenolic hydroxyl group, known products such as phenol novolak resin, alkylphenol novolak resin, bisphenol A novolak resin, dicyclopentadiene type phenolic resin, Xylok type phenolic resin, terpene-modified phenolic resin, cresol / naphthol resin, polyvinylphenols, phenol / naphthol resin, α-naphthol skeleton-containing phenolic resin, triazine skeleton-containing cresol novolak resin, biphenyl aralkyl type phenolic resin, Xylok type phenol novolak resin can be used.

[0129] The compound having a cyanate ester group is preferably a compound having two or more cyanate ester groups (-OCN) in one molecule. For the compound having a cyanate ester group, any known product can be used. Examples of the compound having a cyanate ester group include, for example, phenol novolak type cyanate resin, alkylphenol novolak type cyanate resin, dicyclopentadiene type cyanate resin, bisphenol A type cyanate resin, bisphenol F type cyanate resin, bisphenol S type cyanate resin. In addition, it may also be a partially triazinized prepolymer.

[0130] Examples of commercially available compounds having a cyanate ester group include phenol novolak type polyfunctional cyanate resin (manufactured by Lonza Japan, PT30S), partially or fully triazinized trimer prepolymer of bisphenol A dicyanate (manufactured by Lonza Japan, BA230S75), cyanate resin containing a dicyclopentadiene structure (manufactured by Lonza Japan, DT-4000, DT-7000), etc.

[0131] The compound having a maleimide group is a compound having a maleimide skeleton, and any known product can be used. The compound having a maleimide group preferably has two or more maleimide skeletons, and more preferably is at least one selected from N,N'-1,3-phenylene dimaleimide, N,N'-1,4-phenylene dimaleimide, N,N'-4,4-diphenylmethane bismaleimide, 1,2-bis(maleimide)ethane, 1,6-bismaleimidehexane, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 2,2'-bis-[4-(4-maleimidephenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene dimaleimide, bis(3-ethyl-5-methyl-4-maleimidephenyl)methane, bisphenol A diphenyl ether bismaleimide, polyphenylmethane maleimide and its oligomers, and a diamine condensate having a maleimide skeleton. The oligomer is an oligomer obtained by condensing a compound having a maleimide group which is a monomer among the above compounds having a maleimide group.

[0132] Examples of commercially available compounds having a maleimide group include BMI-1000 (4,4'-diphenylmethane bismaleimide, manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI-2300 (phenylmethane bismaleimide, manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI-3000 (m-phenylene bismaleimide, manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI-5100 (3,3'-dimethyl-5,5'-dimethyl-4,4'-diphenylmethane bismaleimide, manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI-7000 (4-methyl-1,3,-phenylene bismaleimide, manufactured by Daiwa Kasei Kogyo Co., Ltd.), BMI-TMH ((1,6-bismaleimide-2,2,4-trimethyl)hexane, manufactured by Daiwa Kasei Kogyo Co., Ltd.), MIR-3000 (biphenyl aralkyl type maleimide, manufactured by Nippon Kayaku Co., Ltd.), etc.

[0133] The compounding amounts of the curing agents of the first and second curable resin compositions are respectively, for example, 0.01 to 30% by mass based on the total amount of the solid components of the composition.

[0134] (Thermoplastic resin)

[0135] In order to improve the mechanical strength of the obtained cured film, the first and second curable resin compositions may further contain a thermoplastic resin. The thermoplastic resin is preferably soluble in a solvent. When it is soluble in a solvent, the flexibility after forming a dry film is improved, and the occurrence of cracks and powder falling can be suppressed. Examples of the thermoplastic resin include thermoplastic polyhydroxy polyether resin, phenoxy resin which is a condensate of epichlorohydrin and various bifunctional phenolic compounds, or phenoxy resin in which the hydroxyl groups in the hydroxyl ether part present in its skeleton are esterified with various acid anhydrides and acyl chlorides, polyvinyl acetal resin, polyamide resin, polyamideimide resin, blocked copolymer, rubber particles, etc. The thermoplastic resin may be used alone or in combination of two or more kinds.

[0136] The compounding amounts of the thermoplastic resin in the first and second curable resin compositions are, for example, 0.01 to 10% by mass based on the total solid content of the composition.

[0137] (Stress relaxant)

[0138] The first and second curable resin compositions may contain stress relaxants such as elastomers and rubber particles. As the elastomer, known elastomers can be used. As the elastomer, polyester elastomers, polyurethane elastomers, polyester-type polyurethane elastomers, polyamide elastomers, polyesteramide elastomers, acrylic elastomers, olefin elastomers, etc. can be used. In addition, resins obtained by modifying part or all of the epoxy groups of epoxy resins having various skeletons with a two-terminal carboxylic acid-modified butadiene-acrylonitrile rubber can also be used. Epoxy group-containing polybutadiene elastomers, acrylic group-containing polybutadiene elastomers, hydroxyl group-containing polybutadiene elastomers, hydroxyl group-containing isoprene elastomers, blocked copolymers, etc. can also be used. For example, as trade names, R-45HT, Polybd HTP-9 (manufactured by Idemitsu Kosan Co., Ltd.), Eporide PB3600 (manufactured by Daicel Chemical Industries, Ltd.), DenarexR-45EPT (manufactured by Nagase ChemteX Corporation), Tafselen (manufactured by Sumitomo Chemical Co., Ltd.), Ricon 130, Ricon 131, Ricon 134, Ricon 142, Ricon 150, Ricon 152, Ricon 153, Ricon154, Ricon 156, Ricon 157, Ricon 100, Ricon 181, Ricon 184, Ricon 130MA8, Ricon130MA13, Ricon 130MA20, Ricon 131MA5, Ricon 131MA10, Ricon 131MA17, Ricon 131MA20, Ricon 184MA6, Ricon 156MA17 (manufactured by SARTOMER Company, etc.) can be cited.

[0139] Examples of the rubber-like particles include polybutadiene rubber, polyisopropene rubber, polyurethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl-modified polybutadiene rubber, carboxyl- or hydroxyl-modified acrylonitrile-butadiene rubber, and crosslinked rubber particles and core-shell rubber particles of these rubbers. By adding these rubber-like particles, the flexibility of the resulting cured coating film can be improved, and the crack resistance can be enhanced, so that the surface can be roughened with an oxidant, and the adhesion strength with a copper foil or the like can be increased.

[0140] The stress relaxant can be used alone or in combination of two or more kinds. Preferably, the compounding amounts of the stress relaxants in the first and second curable resin compositions are 1 to 10% by mass relative to the total solid content of the compositions, respectively.

[0141] (Flame retardant)

[0142] The first and second curable resin compositions may contain a flame retardant. As the flame retardant, known and conventional flame retardants can be used. Examples of the known and conventional flame retardants include phosphorus compounds such as phosphoric acid esters and condensed phosphoric acid esters, phosphorus-containing (meth)acrylate esters, phosphorus-containing compounds having a phenolic hydroxyl group, cyclophosphazene compounds, phosphazene oligomers, and metal salts of hypophosphorous acid, antimony compounds such as antimony trioxide and antimony pentoxide, halogenated compounds such as pentabromodiphenyl ether and octabromodiphenyl ether, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, and layered double hydroxides such as hydrotalcite and hydrotalcite-like compounds. The flame retardant can be used alone or in combination of two or more kinds.

[0143] The compounding amounts of the flame retardants in the first and second curable resin compositions are, for example, 0.01 to 10% by mass relative to the total solid content of the compositions, respectively.

[0144] (Colorant)

[0145] The first and second curable resin compositions may further contain a colorant. As the colorant, known colorants such as red, blue, green, yellow, black, and white can be used, and any one of pigments, dyes, and pigments can be used. However, from the perspective of reducing the environmental load and the impact on the human body, halogen-free is preferred. The colorant can be used alone or in combination of two or more kinds.

[0146] The compounding amounts of the colorants in the first and second curable resin compositions are, for example, 0.01 to 10% by mass relative to the total solid content of the compositions, respectively.

[0147] (Organic solvent)

[0148] For purposes such as the preparation of the composition and viscosity adjustment when coating a substrate or a carrier film, the first and second curable resin compositions may contain an organic solvent. As the organic solvent, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, diethylene glycol monomethyl ether acetate, and tripropylene glycol monomethyl ether; esters such as ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha and other well-known and conventional organic solvents can be used. These organic solvents can be used alone or in combination of two or more.

[0149] (Other optional components)

[0150] In addition, other additives well-known and conventional in the field of electronic materials can also be added to the first and second curable resin compositions and the cured product layer. As other additives, thermal polymerization inhibitors, silane coupling agents, plasticizers, antistatic agents, anti-aging agents, antioxidants, antibacterial and fungicidal agents, defoaming agents, leveling agents, tackifiers, adhesion improvers, thixotropic agents, photoinitiator aids, sensitizers, organic fillers, release agents, surface treatment agents, dispersants, dispersion aids, surface modifiers, stabilizers, fluorescent powders, etc. can be cited.

[0151] The first curable resin composition is not particularly limited and can be any one of, for example, a thermosetting resin composition, a photocurable thermosetting resin composition, and a photosensitive thermosetting resin composition. In addition, it can be alkali-developable, and can be negative or positive. As specific examples, a photocurable thermosetting resin composition containing a photoinitiator, a photocurable thermosetting resin composition containing a photo-base generator, a negative photocurable thermosetting resin composition, a positive photosensitive thermosetting resin composition, an alkali-developable photocurable thermosetting resin composition, a solvent-developable photocurable thermosetting resin composition, etc. can be cited, but are not limited thereto.

[0152] For the optional components contained in the first and second curable resin compositions and the cured product layer, well-known and conventional components can be selected according to the curability and use.

[0153] The first and second curable resin compositions can be used either as dry films or in liquid form. When used in liquid form, they can be either single-component or two-component or more. In addition, the first and second curable resin compositions can be provided as a set. In this case, both can be in liquid form or dry film form, or one can be in liquid form and the other in dry film form.

[0154] The dry film of the present invention has a resin layer obtained by coating the first curable resin composition or the second curable resin composition on a carrier film and drying it. When forming the dry film, first, the curable resin composition is diluted with the above-mentioned organic solvent to adjust the viscosity to an appropriate value, and then it is coated on the carrier film to a uniform thickness using a comma coater, a knife coater, a lip coater, a rod coater, an extrusion coater, a reverse coater, a transfer roll coater, an intaglio coater, a spray coater, etc. Thereafter, the coated composition is dried at a temperature of generally 40 to 130°C for 1 to 30 minutes to form a resin layer. The coating film thickness is not particularly limited, and generally, it is appropriately selected in the range of 3 to 150 μm, preferably 5 to 60 μm, in terms of the dried film thickness.

[0155] As the carrier film, a plastic film can be used. For example, polyester films such as polyethylene terephthalate (PET), polyimide films, polyamideimide films, polypropylene films, polystyrene films, etc. can be used. The thickness of the carrier film is not particularly limited and is generally appropriately selected in the range of 10 to 150 μm. More preferably, it is in the range of 15 to 130 μm.

[0156] After forming a resin layer of the curable resin composition on the carrier film, for the purpose of preventing dust etc. from adhering to the surface of the resin layer, it is also preferable to laminate a peelable cover film on the surface of the resin layer. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper, etc. can be used. As the cover film, as long as the adhesion force when peeling the cover film is less than the adhesion force between the resin layer and the carrier film.

[0157] It should be noted that in the present invention, the curable resin composition can also be coated on the above-mentioned cover film and dried to form a resin layer, and then a carrier film is laminated on its surface. That is, in the present invention, as the film for coating the curable resin composition when manufacturing the dry film, either the carrier film or the cover film can be used.

[0158] The manufacturing method of the laminated cured body of the present invention is a manufacturing method of a laminated cured body in which a (A) first cured layer formed from the first curable resin composition and a (B) second cured layer formed from a negative-type second curable resin composition are sequentially laminated on a circuit board, and is characterized by including the following steps:

[0159] A step of forming a first cured layer (A) on a circuit board, the first cured layer (A) being formed from the first curable resin composition that does not contain an inorganic filler or contains an inorganic filler in an amount less than that of the negative-type second curable resin composition in terms of solid content;

[0160] A step of forming a second cured layer (B) on the first cured layer (A), the second cured layer (B) being formed from the negative-type second curable resin composition that contains an inorganic filler and an ultraviolet absorber.

[0161] Each step of the method for manufacturing the laminated cured body of the present invention can adopt a conventionally well-known method. Taking the case of manufacturing a printed circuit board as an example, in the step of forming the first cured layer (A), when the first cured layer (A) is formed from an alkali-developable photocurable and thermocurable first curable resin composition, for example, the first curable resin composition is adjusted to a viscosity suitable for the coating method with the above-mentioned organic solvent, and after being coated on the circuit board by methods such as dip coating, flow coating, roll coating, bar coating, screen printing, curtain coating, spin coating, etc., the organic solvent contained in the composition is volatilized and dried (semi-dried) at a temperature of 60 to 100 °C to form a non-sticky resin layer. In addition, in the case of a dry film, the resin layer is laminated on the circuit board in contact with the circuit board by a laminator, etc., and then the carrier film is peeled off to form a resin layer on the substrate.

[0162] As the above-mentioned substrate, in addition to a printed circuit board formed with a circuit such as copper in advance, a flexible printed circuit board, etc., copper-clad laminates of all grades (such as FR-4, etc.) made of materials such as paper-phenolic resin, paper-epoxy resin, glass cloth-epoxy resin, glass-polyimide, glass cloth / non-woven fabric-epoxy resin, glass cloth / paper-epoxy resin, synthetic fiber-epoxy resin, fluororesin, polyethylene, polyphenylene oxide (polyphenylene oxide), cyanate ester, etc. for high-frequency circuits can also be cited, as well as metal substrates, polyimide films, polyethylene terephthalate films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafer boards, etc. A pretreatment can be applied to the circuit. For example, a pretreatment can be applied with GliCAP manufactured by Shikoku Kasei Co., Ltd., New Organic AP (Adhesion promoter) manufactured by MEC Co., Ltd., Nova Bond manufactured by Atotech (Japan) Co., Ltd., etc. to improve the adhesion with a cured coating film such as a solder resist, etc., or a pretreatment can also be applied with an anti-rust agent.

[0163] For the volatilization drying carried out after coating the first curable resin composition, a hot air circulation drying furnace, an IR furnace, a hot plate, a convection oven, etc. (a method of making hot air in the dryer convectively contact by using a device with a heat source utilizing an air heating method using steam and a method of blowing and attaching to the support by a nozzle) can be used.

[0164] After forming a resin layer on the substrate, the (A) first cured product layer thinner than the thickness of the connection circuit of the circuit board is formed by dry etching using oxygen plasma or the like or wet etching using an alkaline aqueous solution or the like. It should be noted that wet etching using an alkaline aqueous solution can be carried out as long as the curable resin composition is alkali-soluble. For example, even in the case of a non-alkali-developable thermosetting resin composition that does not contain a photocurable component as in the composition of Example 1 described later, when a compound having a phenolic hydroxyl group, which is also an alkali-soluble resin, is contained as a curing agent, thinning can be carried out by wet etching.

[0165] After the etching treatment, the cured product layer formed from the first curable resin composition is irradiated with active energy rays and then heat-cured (for example, at 100 to 220 °C), or irradiated with active energy rays after heat-curing, or it can also be finally cured (formally cured) only by heat-curing. As described above, it is preferably formally cured simultaneously with the layer formed from the second curable resin composition.

[0166] As the exposure machine for the above active energy ray irradiation, a device equipped with a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc. and irradiating ultraviolet rays in the range of 350 to 450 nm can be used. In addition, a direct drawing device (for example, a laser direct imaging device that directly draws an image using CAD data from a computer with a laser) can also be used. As the light source or laser source of the direct drawing machine, as long as the maximum wavelength is in the range of 350 to 410 nm. The exposure amount for forming an image varies depending on the film thickness and the like, and generally can be made in the range of 10 to 1000 mJ / cm 2 、preferably 20 to 800 mJ / cm 2 range.

[0167] As the above developing method, an immersion method, a rinsing method, a spraying method, a brushing method, etc. can be used. As the developer, an alkaline aqueous solution of potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, ammonia, amines, etc. can be used.

[0168] In addition, in the process of forming the (B) second cured product layer, for example, a negative-type second curable resin composition is adjusted to a viscosity suitable for the coating method with the above-mentioned organic solvent, coated on the (A) first cured product layer, and then the organic solvent contained in the composition is volatilized and dried (semi-dried) at a temperature of 60 to 100°C, thereby forming a non-sticky resin layer on the (A) first cured product layer. In addition, in the case of a dry film, it is adhered to the (A) first cured product layer in a manner that the resin layer is in contact with the (A) first cured product layer through a laminator or the like, and then the carrier film is peeled off, thereby forming a resin layer on the (A) first cured product layer. The volatilization and drying after coating can be carried out in the same manner as described above.

[0169] After forming a resin layer on the (A) first cured product layer, through a photomask having a specified pattern, selective exposure is carried out using actinic energy rays, and the unexposed portion is developed with a dilute alkali aqueous solution (for example, 0.3 to 3 mass% sodium carbonate aqueous solution), thereby forming a pattern of the cured product. Further, after irradiating the cured product with actinic energy rays, heat curing is carried out (for example, 100 to 220°C), or heat curing is carried out and then actinic energy rays are irradiated, or only heat curing is carried out to finally complete curing (formal curing), thereby forming a cured film having excellent properties such as adhesion and hardness. Exposure and development can be carried out in the same manner as described above.

[0170] It should be noted that in the case where the first curable resin composition is photo-curable and thermo-curable, before etching, the resin layer is irradiated with an exposure dose of 10 to 1000 mJ / cm 2 using a UV conveyor furnace, and then heated at 100 to 220°C for 5 to 60 minutes to formally cure the first layer. In addition, in the case where the first curable resin composition is thermo-curable, the first layer can be heated at 100 to 220°C for 5 to 60 minutes before etching. In addition, in the case where the second layer is thermo-curable, the second layer can be heated at 100 to 220°C for 5 to 60 minutes to form a cured film.

[0171] The laminated cured body of the present invention is preferably used for electronic devices, especially printed circuit boards, more preferably used for circuit boards having a permanent coating film, and further preferably used for circuit boards having permanent insulating coating films such as solder resist, interlayer insulating layers, and cover layers. In addition, it is suitable for printed circuit boards requiring high reliability, such as package substrates, especially circuit boards for FC-BGA.

[0172] Examples

[0173] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. It should be noted that hereinafter, "parts" and "%" are all based on mass unless otherwise specified. The values shown in Table 1 are mass parts of the solid component excluding the solvent.

[0174] [Synthesis of alkali-soluble resin]

[0175] (Synthesis Example 1: Alkali-soluble resin A-1)

[0176] In a flask equipped with a condenser and a stirrer, 456 parts of bisphenol A, 228 parts of water, and 649 parts of 37% formalin were charged. While maintaining the temperature below 40 °C, 228 parts of 25% aqueous sodium hydroxide solution was added. After the addition, the reaction was carried out at 50 °C for 10 hours. After the reaction was completed, it was cooled to 40 °C, and neutralized to pH 4 with 37.5% aqueous phosphoric acid solution while maintaining the temperature below 40 °C. Thereafter, the aqueous layer was allowed to stand and separated. After separation, 300 parts of methyl isobutyl ketone was added, and after dissolving uniformly, it was washed 3 times with 500 parts of distilled water, and water, solvents, etc. were removed under reduced pressure at a temperature below 50 °C. The obtained polyhydroxymethyl compound was dissolved in 550 parts of methanol to obtain 1230 parts of a polyhydroxymethyl compound methanol solution.

[0177] A part of the obtained polyhydroxymethyl compound methanol solution was dried at room temperature in a vacuum dryer, and the solid content was 55.2%.

[0178] In a flask equipped with a condenser and a stirrer, 500 parts of the obtained polyhydroxymethyl compound methanol solution and 440 parts of 2,6-xylenol were charged and dissolved uniformly at 50 °C. After dissolving uniformly, methanol was removed under reduced pressure at a temperature below 50 °C. Thereafter, 8 parts of oxalic acid was added, and the reaction was carried out at 100 °C for 10 hours. After the reaction was completed, the distillate was removed under reduced pressure at 180 °C and 50 mmHg to obtain 550 parts of novolak resin A.

[0179] In an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device and a stirring device, 130 parts of novolak resin A, 2.6 parts of 50% aqueous sodium hydroxide solution, and 100 parts of toluene / methyl isobutyl ketone (mass ratio = 2 / 1) were charged. While stirring, the system was purged with nitrogen, and then heated and raised in temperature. 60 parts of propylene oxide was slowly introduced at 150 °C and 8 kg / cm 2 for reaction. The reaction continued for about 4 hours until the gauge pressure dropped to 0.0 kg / cm 2 and then it was cooled to room temperature. 3.3 parts of 36% aqueous hydrochloric acid solution was added and mixed in this reaction solution to neutralize sodium hydroxide. The by-product of this neutralization reaction was diluted with toluene, washed 3 times with water, and the solvent was removed with an evaporator to obtain an adduct of propylene oxide of novolak resin A with a hydroxyl value of 189 g / eq.. It is a product in which 1 mole of propylene oxide is added on average per 1 equivalent of phenolic hydroxyl group.

[0180] 189 parts of the propylene oxide adduct of the obtained novolac resin A, 36 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.1 part of hydroquinone monomethyl ether, and 140 parts of toluene were put into a reactor equipped with a stirrer, a thermometer, and an air blowing tube. While blowing air and stirring, the temperature was raised to 115 °C, and the water generated by the reaction was distilled off as an azeotropic mixture with toluene. After reacting for another 4 hours, it was cooled to room temperature. The obtained reaction solution was washed with a 5% NaCl aqueous solution, and after removing toluene by vacuum distillation, diethylene glycol monoethyl ether acetate was added to obtain an acrylate resin solution with a solid content of 67%.

[0181] Next, 322 parts of the obtained acrylate resin solution, 0.1 part of hydroquinone monomethyl ether, and 0.3 part of triphenylphosphine were put into a four-necked flask equipped with a stirrer and a reflux condenser. The mixture was heated to 110 °C, 60 parts of tetrahydrophthalic anhydride was added, and the reaction was carried out for 4 hours. After cooling, it was taken out. The obtained solution of the photosensitive carboxyl group-containing resin A-1 had a solid content of 70% and a solid content acid value of 81 mgKOH / g.

[0182] (Synthesis Example 2: Alkali-soluble resin A-2)

[0183] In an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device and a stirring device, 119.4 parts of a novolac type cresol novolac resin (trade name “Shonol CRG951”, manufactured by Showa Denko KK, OH equivalent: 119.4), 1.19 parts of potassium hydroxide, and 119.4 parts of toluene were introduced. While stirring, the system was purged with nitrogen and heated. Next, 63.8 parts of propylene oxide was slowly added dropwise, and the reaction was carried out at 125 - 132 °C and 0 - 4.8 kg / cm 2 for 16 hours. Thereafter, it was cooled to room temperature, and 1.56 parts of 89% phosphoric acid was added and mixed in the reaction solution to neutralize potassium hydroxide, obtaining a reaction solution of a novolac type cresol novolac resin with an epoxy propane having a non-volatile content of 62.1% and a hydroxyl value of 182.2 mgKOH / g (307.9 g / eq.). It was a product obtained by adding 1.08 moles of propylene oxide per 1 equivalent of phenolic hydroxyl group on average.

[0184] 293.0 parts of the reaction solution of novolac cresol formaldehyde resin and propylene oxide, 43.2 parts of acrylic acid, 11.53 parts of methanesulfonic acid, 0.18 part of methylhydroquinone, and 252.9 parts of toluene were introduced into a reactor equipped with a stirrer, a thermometer, and an air blowing tube. Air was blown in at a rate of 10 ml / min, and the reaction was carried out at 110°C for 12 hours while stirring. 12.6 parts of water generated by the reaction was distilled off as an azeotropic mixture with toluene. Thereafter, it was cooled to room temperature, and the resulting reaction solution was neutralized with 35.35 parts of 15% aqueous sodium hydroxide solution, followed by washing with water. Thereafter, toluene was distilled off while being replaced with 118.1 parts of diethylene glycol monoethyl ether acetate using an evaporator to obtain a novolac acrylate resin solution. Next, 332.5 parts of the obtained novolac acrylate resin solution and 1.22 parts of triphenylphosphine were introduced into a reactor equipped with a stirrer, a thermometer, and an air blowing tube. Air was blown in at a rate of 10 ml / min, and 60.8 parts of tetrahydrophthalic anhydride was slowly added while stirring. The reaction was carried out at 95 - 101°C for 6 hours, and after cooling, it was taken out. Thus, a solution of carboxyl group-containing photosensitive resin A-2 with a non-volatile content of 65% and an acid value of the solid substance of 80 mgKOH / g was obtained.

[0185] [Preparation of Filler]

[0186] (Adjustment Example 1: Solvent dispersion product K-1 of surface-treated silica)

[0187] 60 g of spherical silica (SFP-20M manufactured by Denka Company Limited, average particle size: 400 nm), 38 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and 2 g of a silane coupling agent having a methacryloyl group (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) were uniformly dispersed to obtain a solvent dispersion product K-1 of silica.

[0188] (Adjustment Example 2: Solvent dispersion product K-2 of surface-treated silica)

[0189] 60 g of spherical silica (SFP-20M manufactured by Denka Company Limited, average particle size: 400 nm), 38 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and 2 g of a silane coupling agent having an amino group (KBM-573 manufactured by Shin-Etsu Chemical Co., Ltd.) were uniformly dispersed to obtain a solvent dispersion product K-2 of silica.

[0190] (Adjustment Example 3: Solvent dispersion product K-3 of surface-treated barium sulfate)

[0191] 60 g of barium sulfate (B-30 manufactured by Sakai Chemical Industry Co., Ltd., average particle size: 300 nm), 35 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and 5 g of a wetting dispersant were uniformly dispersed to obtain a solvent dispersion product K-3 of barium.

[0192] (Adjustment Example 4: Solvent dispersion product K-4 of surface-treated alumina)

[0193] 50 g of spherical alumina particles (ASFP-20 manufactured by Denka Company Limited, average particle diameter: 300 nm), 48 g of PMA (propylene glycol monomethyl ether acetate) as a solvent, and 2 g of a silane coupling agent having an amino group (KBE-903 manufactured by Shin-Etsu Chemical Co., Ltd.) were uniformly dispersed to obtain a solvent dispersion product K-4 of alumina.

[0194] [Production of Core-Shell Rubber I-1]

[0195] 1300 g of rubber latex and 440 g of pure water were put into a 3-liter glass reactor, and the mixture was heated to 70 °C with stirring under the introduction of nitrogen. This rubber latex contained 480 g of polybutadiene particles with an average particle diameter of 0.1 μm and 1.5% by mass of sodium dodecylbenzenesulfonate when the polybutadiene was 100% by mass. After adding 1.2 g of azobisisobutyronitrile thereto, a mixture of 36 g of styrene, 48 g of methyl methacrylate, and 24 g of acrylonitrile was added over 3 hours. Thereafter, it was stirred for another 2 hours to obtain core-shell rubber particles (latex (L)). The solid content of latex (L) was 32%. In addition, the gel fraction of the core-shell copolymer in latex (L) was 98%. In addition, the rubber particle diameter in latex (L) was 0.5 μm.

[0196] [Compositions of Each Layer of Examples 1 to 7 and Comparative Examples 1 to 4]

[0197] The various components in the table were compounded according to the solid content ratio (parts by mass) shown in the table, pre-mixed using a stirrer, and then kneaded using a bead mill to separately prepare curable resin compositions for the first layer and the second layer.

[0198] <Production of Dry Film>

[0199] 300 g of methyl ethyl ketone was added to the curable resin composition for the first layer adjusted as described above and diluted, and the mixture was stirred for 15 minutes using a stirrer to obtain a coating solution. The coating solution was coated on a polyethylene terephthalate film with a thickness of 38 μm (carrier film: Emblet PTH-25 manufactured by Unitika Ltd.) and dried at a temperature of 100 °C for 15 minutes to form a resin layer with a thickness of 20 μm (however, only in Comparative Examples 2 and 3, the thickness was 25 μm). Then, a biaxially stretched polypropylene film (cover film: OPP-FOA manufactured by Nimura & Co., Ltd.) was laminated on the resin layer to produce a dry film for the first layer. A dry film for the second layer was produced in the same manner as above, except that the thickness of the resin layer was 10 μm.

[0200] <Manufacturing Method of Laminated Cured Body>

[0201] (Examples 1 - 7, Comparative Examples 1, 4 - 6)

[0202] A BT substrate with a pattern of L / S = 20 μm / 15 μm, a conductor pad diameter of 70 μm as a connection circuit, and a conductor thickness of 20 μm as a connection circuit was treated with CZ8101 to prepare a circuit board. On this circuit board, first, using a vacuum laminator (CV-600: manufactured by Nikko Materials Co., Ltd.), after peeling off the cover film of the first dry film for each example and comparative example, lamination was carried out under the conditions of a vacuum pressure of 3 hPa and a vacuum pumping time of 30 seconds in a first chamber at 90°C, and then pressing was carried out under the conditions of a pressing pressure of 0.5 MPa and a pressing time of 30 seconds.

[0203] Thereafter, the carrier film was peeled off, and wet etching with the following etching amount was performed on the uncured resin layer.

[0204] Specifically, thinning treatment was carried out with a 10% by mass aqueous solution of sodium methyl silicate at 25°C to reduce it to a thickness equal to or less than the conductor thickness. Thereafter, the surface of the first resin layer was made uniform by an aqueous solution containing alkali metal carbonate with a pH of 5 - 10 and water washing.

[0205] Next, a second dry film with a thickness of 10 μm was laminated on the first layer under the same conditions as above, and pattern exposure was performed using a DI exposure machine with an exposure amount obtainable in 10 steps under stepwise exposure (41 steps) to form a φ50 μm hollow pattern on the conductor pad. Then, the carrier film was peeled off, and development was carried out for 60 seconds (1% by mass Na2CO3, 30°C, 0.2 MPa) to form a pattern of the resin layer. Next, after irradiating the resin layer with an exposure amount of 1 J / cm 2 using a UV conveyor furnace equipped with a high-pressure mercury lamp, the resin layer was heated at 160°C for 60 minutes to formally cure the resin layer, and an evaluation substrate with a pattern cured film was produced.

[0206] (Comparative Examples 2, 3)

[0207] Similarly to the above, on the substrate, after laminating under the above lamination conditions, pattern exposure was performed using a DI exposure machine with an exposure amount obtainable in 10 steps under stepwise exposure (41 steps) to form a φ50 μm hollow pattern on the conductor pad. Then, the PET film was peeled off, and development was carried out for 60 seconds (1% by mass Na2CO3, 30°C, 0.2 MPa) to form a pattern of the resin layer. Next, after irradiating the resin layer with an exposure amount of 1 J / cm 2 using a UV conveyor furnace equipped with a high-pressure mercury lamp, the resin layer was heated at 160°C for 60 minutes to formally cure the resin layer, and an evaluation substrate with a pattern cured film was produced.

[0208] (Comparative Example 7)

[0209] In the same manner as above, but without forming the first resin layer on the substrate, a second dry film with a thickness of 10 μm was laminated on the substrate under the same conditions as above. Pattern exposure was performed using a DI exposure machine with an exposure amount achievable in 10 steps out of 41 steps of stepwise exposure to form a φ50 μm hollow pattern on the conductor pad. Then, the carrier film was peeled off, and development was carried out for 60 seconds (1 mass% Na2CO3, 30 °C, 0.2 MPa) to form a pattern of the resin layer. Next, after irradiating the resin layer with an exposure amount of 1 J / cm 2 using a UV conveyor furnace equipped with a high-pressure mercury lamp, the resin layer was heated at 160 °C for 60 minutes to formally cure the resin layer, and an evaluation substrate with a pattern-cured film was produced.

[0210] (Etching amount)

[0211] For the conductor thickness, etching was performed to make the first resin layer reach the following thickness.

[0212] 1. Thinner than the conductor thickness, and the thinning ratio is greater than 30% and at most 70%

[0213] 2. Thinner than the conductor thickness, and the thinning ratio is greater than 10% and at most 30%

[0214] 3. Thinner than the conductor thickness, and the thinning ratio is 5% or more and at most 10%

[0215] 4. Equal to the conductor thickness (0%)

[0216] <Filling property>

[0217] After subjecting a substrate with a circuit pattern having a conductor thickness of 15 μm and L / S = 12 μm / 12 μm to acid treatment using CZ8101, the one-layer dry films of Examples 1 to 7 and Comparative Examples 1 to 6 were laminated based on the above production method, and the filling property was confirmed by SEM observation of the cross section. In Comparative Example 7, the second-layer dry film was laminated, and the filling property was confirmed by SEM observation of the cross section.

[0218] ◎: No voids in filling.

[0219] ×: Voids of about 1 to 2 μm were confirmed to exist.

[0220] <Insulation reliability>

[0221] Using the above laminate cured body, the HAST test was carried out under the conditions of 130 °C, humidity 85%, and 5 V.

[0222] ◎: Insulation reliability of 300 hours or more was achieved.

[0223] △: Insulation reliability of more than 200 hours and less than 300 hours.

[0224] ×: Insulation reliability less than 200 hours.

[0225] <Resolution>

[0226] The φ50μm opening cross-sectional shapes formed in Examples 1 to 7 and Comparative Examples 1 to 7 were observed by SEM.

[0227] ◎: 1.0 < Top / Bottom ratio ≤ 1.2

[0228] ○: 1.2 < Top / Bottom ratio ≤ 1.3

[0229] △: 1.3 < Top / Bottom ratio ≤ 1.4 or 0.9 < Top / Bottom ratio ≤ 1.0

[0230] ×: 1.4 < Top / Bottom ratio or Top / Bottom ratio ≤ 0.9

[0231] Table 1

[0232]

[0233] Table 2

[0234]

[0235] A-1: The alkali-soluble resin A-1 synthesized in Synthesis Example 1 above

[0236] A-2: The alkali-soluble resin A-2 synthesized in Synthesis Example 2 above

[0237] B-1: Omnirad907 (2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one) manufactured by IGM Resins

[0238] B-2: OmniradTPO (2,4,6-trimethylbenzoyl-diphenyl-oxide phosphine) manufactured by IGM Resins

[0239] C-1: DPHA (dipentaerythritol hexaacrylate) manufactured by Nippon Kayaku Co., Ltd.

[0240] D-1: EPICLON n-770 (phenolic novolak type epoxy resin, epoxy equivalent 188 g / eq., softening point 70 °C) manufactured by DIC Corporation

[0241] D-2: NC-3000 (biphenyl type epoxy resin, epoxy equivalent 290 g / eq., softening point 57 °C) manufactured by Nippon Kayaku Co., Ltd.

[0242] D-3: EPICLON n-695 (cresol novolak type epoxy resin, epoxy equivalent 215 g / eq., softening point 95 °C) manufactured by DIC Corporation

[0243] D-4: NC-6000 manufactured by Nippon Kayaku Co., Ltd. (glycidyl ether compound of 2-(4-hydroxyphenyl)-2-[4-[1,1-bis(4-hydroxyphenyl)ethyl]phenyl]propane, epoxy equivalent 210 g / eq.)

[0244] D-5: NC-3000H manufactured by Nippon Kayaku Co., Ltd. (bisphenol novolac type epoxy resin, epoxy equivalent 290 g / eq.)

[0245] E-1: FX-293 manufactured by Nippon Steel Chemical & Material Co., Ltd. (phenoxy resin)

[0246] F-1: HF-1M manufactured by Meiwafosis Co., Ltd. (phenol novolac resin)

[0247] F-2: LA-3018 manufactured by DIC Corporation (novolac resin)

[0248] G-1: Phthalocyanine Blue manufactured by Tokyo Chemical Industry Co., Ltd.

[0249] H-1: DICY (dicyandiamide) manufactured by Tokyo Chemical Industry Co., Ltd.

[0250] H-2: DMAP (4-dimethylaminopyridine) manufactured by Tokyo Chemical Industry Co., Ltd.

[0251] H-3: Melamine manufactured by Tokyo Chemical Industry Co., Ltd.

[0252] I-1: Core-shell rubber I-1 prepared as described above

[0253] J-1: HCA-HQ (10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) manufactured by Mitsuho Corporation

[0254] K-1: Solvent dispersion of silica surface-treated with a silane coupling agent having a methacryloyl group, prepared as described above

[0255] K-2: Solvent dispersion of silica surface-treated with a silane coupling agent having an amino group, prepared as described above

[0256] K-3: Solvent dispersion of barium sulfate (B-30 manufactured by Sakai Chemical Industry Co., Ltd., barium sulfate surface-treated with silica alumina), prepared as described above

[0257] K-4: Solvent dispersion of alumina surface-treated with a silane coupling agent having an amino group, prepared as described above

[0258] K-5: MEK-AC-4130Y (methyl ethyl ketone dispersed silica sol) manufactured by Nissan Chemical Industries, Ltd.

[0259] L-1: TINUVIN 460 (2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-bis-butoxyphenyl)-1,3,5-triazine) manufactured by BASF Japan Ltd.

[0260] L-2: TKF-428 (naphthoquinone diazide adduct of 4-{4-[1,1-bis(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl}phenol, solid component concentration 100 mass%) manufactured by Sanpo Chemical Research Institute Co., Ltd.

[0261] From the results shown in the above table, it can be seen that the laminated cured bodies of Examples 1 to 7 of the present invention have both landfillability, insulation reliability, and resolution.

Claims

1. A laminated cured body, which is a laminated cured body obtained by sequentially laminating (A) a first cured layer formed of a first curable resin composition and (B) a second cured layer formed of a negative second curable resin composition on a circuit board. It is characterized in that The thickness of the (A) first cured layer is thinner than the thickness of the connection circuit of the circuit board. The negative second curable resin composition contains an alkali-soluble resin, a photoinitiator capable of generating free radicals by light irradiation to cure the composition, a photocurable resin, a thermosetting resin, an inorganic filler, and an ultraviolet absorber. The ultraviolet absorber contains a diazonaphthoquinone compound and an organic ultraviolet absorber other than the diazonaphthoquinone compound. The organic ultraviolet absorber is a triazine derivative. The first curable resin composition does not contain an inorganic filler, or contains an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content conversion. When the first curable resin composition contains an inorganic filler, the content of the inorganic filler is 30% by mass or less in the total solid content of the first curable resin composition, and is at least 5% by mass less than the content of the inorganic filler in the total solid content of the second curable resin composition. The content of the inorganic filler in the second curable resin composition is 20% by mass or more and 85% by mass or less in the total solid content of the second curable resin composition. The laminated cured body is obtained by a manufacturing method including the following steps: A step of coating the first curable resin composition on the circuit board and drying it, or laminating a resin layer in the form of a dry film to form an uncured resin layer formed of the first curable resin composition. Thereafter, a step of wet-etching the uncured resin layer formed of the first curable resin composition such that when the thickness of the connection circuit of the circuit board is set to 100%, the thickness of the first cured layer is 1 to 30% thinner than it. A step of forming the (B) second cured layer formed of the negative second curable resin composition on the wet-etched resin layer, and at the same time, the wet-etched resin layer forms the (A) first cured layer.

2. The laminated solidified body according to claim 1, characterized in that, It is a semiconductor packaging substrate.

3. A manufacturing method of a laminated cured body, which is a manufacturing method of a laminated cured body obtained by sequentially laminating (A) a first cured layer formed of a first curable resin composition and (B) a second cured layer formed of a negative second curable resin composition on a circuit board. It is characterized in that It includes the following steps: A step of coating the first curable resin composition on the circuit board and drying it, or laminating a resin layer in the form of a dry film to form an uncured resin layer formed of the first curable resin composition. The first curable resin composition does not contain an inorganic filler, or contains an inorganic filler in an amount less than that of the negative second curable resin composition in terms of solid content conversion. Subsequently, when the thickness of the connection circuit of the circuit board is set to 100%, a step of wet-etching the uncured resin layer formed of the first curable resin composition is performed such that the thickness of the first cured product layer is 1 to 30% thinner than that, A step of forming the (B) second cured product layer on the resin layer subjected to the wet-etching treatment, and the resin layer subjected to the wet-etching treatment forms the (A) first cured product layer. The (B) second cured product layer is formed of the negative-type second curable resin composition. The negative-type second curable resin composition contains an alkali-soluble resin, a photoinitiator capable of generating free radicals by light irradiation to cure the composition, a photocurable resin, a thermosetting resin, an inorganic filler, and an ultraviolet absorber, The ultraviolet absorber contains a diazonaphthoquinone compound and an organic ultraviolet absorber other than the diazonaphthoquinone compound. The organic ultraviolet absorber is a triazine derivative, When the first curable resin composition contains an inorganic filler, the content of the inorganic filler is 30% by mass or less in the total solid content of the first curable resin composition, and is 5% by mass or more less than the content of the inorganic filler in the total solid content of the second curable resin composition, The content of the inorganic filler in the second curable resin composition is 20% by mass or more and 85% by mass or less in the total solid content of the second curable resin composition.

Images