Photosensitive resin composition, photosensitive element, printed wiring board, and method for manufacturing printed wiring board

Abstract

To provide a photosensitive resin composition which has excellent developability and furthermore enables suppression of undercut.SOLUTION: A photosensitive resin composition is provided, containing acid-modified vinyl group-containing resin (A), thermosetting resin (B), a photopolymerization initiator (C), and photopolymerizable compound (D) (excluding a compound corresponding to the acid-modified vinyl group-containing resin (A)), wherein the photopolymerizable compound (D) includes a (meth)acrylic monomer having the number of (meth)acrylic groups of 5 to 10 and the number of ethylene oxide chains of 0 to 24.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a photosensitive resin composition, a photosensitive element, a printed wiring board, and a method for producing a printed wiring board. [Background technology]

[0002] In the field of printed wiring board manufacturing, resist is formed on printed wiring boards. The resist has the role of preventing corrosion of the conductor layer and maintaining electrical insulation between the conductor layers when the printed wiring board is in use.

[0003] In recent years, electronic devices have become smaller and more powerful, and multilayer printed wiring boards have become increasingly dense due to an increase in the number of circuit layers and finer wiring. In particular, the density of semiconductor package substrates, such as BGAs (ball grid arrays) and CSPs (chip-sized packages), on which semiconductor chips are mounted, has increased significantly. This has led to demands for thinner insulating films and smaller diameters of vias (also called "via holes") for interlayer connection, in addition to finer wiring. Furthermore, as insulating films in printed wiring boards become thinner, excellent interlayer electrical insulation reliability, particularly electrical insulation reliability after moisture absorption (high accelerated stress test (HAST) resistance), is required. One known method for improving both high resolution and electrical insulation reliability is, for example, the addition of a benzoxazine compound to increase adhesive strength with plated copper (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-24857 Summary of the Invention [Problem to be solved by the invention]

[0005] As printed wiring boards become more highly integrated, there is a demand for the ability to open vias of various diameters with good shapes using the same photosensitive resin composition. For small vias with a mask diameter of approximately 20 mm, the opening diameter of the via tends to be smaller than the mask, while for large vias with a mask diameter of approximately 50 mm, the developer tends to penetrate to the bottom of the via, which can result in undercut. Increasing the opening diameter of small vias requires improving developability, but this is a trade-off with undercutting in large vias, making it difficult to achieve both improved developability and suppression of undercutting.

[0006] Therefore, an object of the present disclosure is to provide a photosensitive resin composition that has excellent developability and can suppress undercut, a photosensitive element and a printed wiring board that use the photosensitive resin composition, and a method for producing a printed wiring board. [Means for solving the problem]

[0007] The present disclosure includes, for example, the following [1] to

[14] .

[0008] [1] A composition comprising (A) an acid-modified vinyl group-containing resin, (B) a thermosetting resin, (C) a photopolymerization initiator, and (D) a photopolymerizable compound (excluding compounds corresponding to the acid-modified vinyl group-containing resin (A)), A photosensitive resin composition, wherein the (D) photopolymerizable compound contains a (meth)acrylic monomer having 5 to 10 (meth)acrylic groups and 0 to 24 ethylene oxide chains. [2] The photosensitive resin composition according to [1], wherein the number of the (meth)acrylic groups is 5 or 6. [3] The photosensitive resin composition according to [1], wherein the number of ethylene oxide chains is 0 to 6. [4] The photosensitive resin composition according to any one of [1] to [3], wherein the number of ethylene oxide chains is 12 to 24. [5] The photosensitive resin composition according to any one of [1] to [4], wherein the (A) acid-modified vinyl group-containing resin has a dicyclopentadiene skeleton. [6] The photosensitive resin composition according to any one of [1] to [5], further comprising (E) an inorganic filler. [7] The photosensitive resin composition according to [6], wherein the inorganic filler (E) is silica. [8] The photosensitive resin composition according to any one of [1] to [7], further comprising (F) a pigment. [9] A photosensitive film comprising: a support film; and a photosensitive layer formed on the support film; A photosensitive element, wherein the photosensitive layer comprises the photosensitive resin composition according to any one of [1] to [8].

[10] A printed wiring board comprising an interlayer insulating layer containing a cured product of the photosensitive resin composition according to any one of [1] to [8].

[11] A step of forming a photosensitive layer on a substrate using the photosensitive resin composition according to any one of [1] to [8]; a step of exposing and developing the photosensitive layer to form a resist pattern; hardening the resist pattern to form an interlayer insulating layer; A method for manufacturing a printed wiring board, comprising:

[12] A step of forming a photosensitive layer on a substrate using the photosensitive element described in [9]; a step of exposing and developing the photosensitive layer to form a resist pattern; hardening the resist pattern to form an interlayer insulating layer; A method for manufacturing a printed wiring board, comprising: [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a photosensitive resin composition that has excellent developability and can suppress undercut, a photosensitive element and a printed wiring board that use the photosensitive resin composition, and a method for producing a printed wiring board. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view schematically illustrating a photosensitive element according to an embodiment of the present invention. [Figure 2]1A to 1C are schematic diagrams illustrating one aspect of a method for manufacturing a printed wiring board according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present disclosure will be described in detail below. In this specification, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the process achieves its intended effect. The term "layer" includes a structure having a shape formed on the entire surface when observed in a plan view, as well as a structure having a shape formed on a portion of the surface.

[0012] In this specification, a numerical range indicated using "to" indicates a range that includes the numerical values before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit of a numerical range in a certain stage may be replaced with the upper or lower limit of a numerical range in another stage, or may be replaced with a value shown in an example. In this specification, for example, the expression "10 or more" means 10 and a numerical value exceeding 10, and this also applies when the numerical values are different. Furthermore, for example, the expression "10 or less" means a numerical value of 10 and a numerical value less than 10, and this also applies when the numerical values are different.

[0013] In this specification, the content of each component in a composition refers to the total content of the multiple substances present in the composition when multiple substances corresponding to each component are present in the composition, unless otherwise specified. In this specification, the term "ring member number" refers to the number of carbon atoms required to form a ring, and does not include the number of carbon atoms of the substituents on the ring. In this specification, "(meth)acrylate" refers to at least one of "acrylate" and its corresponding "methacrylate," and the same applies to other similar expressions such as (meth)acrylic acid. In this specification, the term "solid content" refers to the non-volatile content of the photosensitive resin composition excluding volatile substances, and includes components that are liquid, syrup-like, or waxy at room temperature (around 25°C).

[0014] [Photosensitive resin composition] The photosensitive resin composition according to this embodiment contains (A) an acid-modified vinyl group-containing resin, (B) a thermosetting resin, (C) a photopolymerization initiator, and (D) a photopolymerizable compound (excluding compounds corresponding to the (A) acid-modified vinyl group-containing resin). The (D) photopolymerizable compound contains a (meth)acrylic monomer having 5 to 10 (meth)acrylic groups and 0 to 24 ethylene oxide chains. The photosensitive resin composition having the above configuration exhibits excellent developability while suppressing undercut. The photosensitive resin composition according to this embodiment is a negative-tone photosensitive resin composition, and a cured product of the photosensitive resin composition can be suitably used as a permanent resist for an interlayer insulating layer, etc. Each component used in the photosensitive resin composition according to this embodiment will be described in more detail below.

[0015] (Component (A): Acid-modified vinyl group-containing resin) The photosensitive resin composition according to this embodiment contains an acid-modified vinyl group-containing resin as component (A). The acid-modified vinyl group-containing resin is not particularly limited as long as it has a vinyl group, which is a photopolymerizable ethylenically unsaturated bond, and an alkali-soluble acidic group. Examples of the acidic group contained in component (A) include a carboxy group, a sulfo group, and a phenolic hydroxyl group. Among these, a carboxy group is preferred from the viewpoint of superior developability.

[0016] Examples of acid-modified vinyl group-containing resins include acid-modified epoxy(meth)acrylates. Acid-modified epoxy(meth)acrylates are resins obtained by acid-modifying epoxy(meth)acrylates, which are reaction products of epoxy resins and organic acids having vinyl groups. Examples of acid-modified epoxy(meth)acrylates include addition reaction products obtained by adding saturated or unsaturated polybasic acid anhydrides (c) to esterified products obtained by reacting epoxy resins (a) with vinyl group-containing monocarboxylic acids (b).

[0017] Examples of the epoxy resin (a) include bisphenol novolac type epoxy resins, novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, triphenolmethane type epoxy resins, biphenyl type epoxy resins, naphthalene type epoxy resins, and dicyclopentadiene type epoxy resins.

[0018] Examples of the vinyl group-containing monocarboxylic acid (b) include acrylic acid, a dimer of acrylic acid, methacrylic acid, (meth)acrylic acid such as β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, and α-cyanocinnamic acid, or a derivative thereof; a half-ester compound which is a reaction product of a hydroxyl group-containing (meth)acrylate with a dibasic acid anhydride; and a half-ester compound which is a reaction product of a vinyl group-containing monoglycidyl ether or a vinyl group-containing monoglycidyl ester with a dibasic acid anhydride.

[0019] Examples of hydroxyl group-containing (meth)acrylates, vinyl group-containing monoglycidyl ethers, and vinyl group-containing monoglycidyl esters include hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, glycidyl acrylate, and glycidyl methacrylate.

[0020] Examples of dibasic acid anhydrides include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride.

[0021] Examples of the saturated or unsaturated polybasic acid anhydride (c) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride. Among these, tetrahydrophthalic anhydride may be used from the viewpoint of superior developability.

[0022] Examples of the acid-modified epoxy(meth)acrylate include (A1) an acid-modified epoxy(meth)acrylate having an alicyclic skeleton and (A2) an acid-modified epoxy(meth)acrylate not having an alicyclic skeleton. From the viewpoints of achieving excellent developability, adhesiveness and electrical insulation reliability of the cured product, and further reducing residue at the bottom of vias when they are formed, it is preferable that the component (A) contains the component (A1).

[0023] The number of ring members in the alicyclic skeleton of component (A1) is preferably 5 to 20, more preferably 5 to 18, even more preferably 6 to 18, particularly preferably 8 to 14, and extremely preferably 8 to 12, from the viewpoints of achieving excellent developability, adhesive properties, and electrical insulation reliability of the cured product, and further reducing residue at the bottom of vias during via formation. From the same viewpoints, the number of rings in the alicyclic skeleton of component (A1) is preferably 2 or more, more preferably 2 to 4, and even more preferably 3. Examples of alicyclic skeletons having one ring include a cyclohexane skeleton and a cyclohexene skeleton, and examples of alicyclic skeletons having two or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, and a saturated dicyclopentadiene skeleton.

[0024] From the viewpoints of achieving excellent developability, adhesive properties and electrical insulation reliability of a cured product, and further reducing residue at the bottom of a via hole during via formation, the component (A1) preferably has a saturated dicyclopentadiene skeleton as the alicyclic skeleton, and more preferably has a saturated dicyclopentadiene skeleton represented by the following formula (a):

[0025] [ka]

[0026] In formula (a), R A1 represents an alkyl group having 1 to 12 carbon atoms, and m 1 is an integer from 0 to 6, and * is a binding site to another structure.

[0027] R A1 Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, and an n-pentyl group. From the viewpoints of achieving better developability, adhesion and electrical insulation reliability of the cured product, and further reducing residue at the bottom of vias when formed, the alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group.

[0028] m 1 is preferably an integer of 0 to 2, more preferably 0. 1 is an integer between 2 and 6, multiple R A1 may be the same or different. A1 may be substituted on the same carbon atom or on different carbon atoms, to the extent possible.

[0029] The component (A1) can be, for example, an addition reaction product obtained by adding a saturated or unsaturated polybasic acid anhydride (c) to an ester obtained by reacting an epoxy resin (a1) having an alicyclic skeleton with a vinyl group-containing monocarboxylic acid (b).

[0030] Examples of the epoxy resin (a1) include glycidyl ether type, glycidyl amine type, and glycidyl ester type. Among these, the glycidyl ether type is preferred.

[0031] The epoxy resin (a1) is preferably an epoxy resin represented by the following formula (a1-1) or an epoxy resin having a structural unit represented by the following formula (a1-2).

[0032] [ka]

[0033] In formula (a1-1), R A1 and m 1 is R in formula (a) A1 and m 1 is the same as R A2 represents an alkyl group having 1 to 12 carbon atoms, and m 2 is an integer of 0 to 3, and n represents the number of structural units in the parentheses, which is 0 to 10.

[0034] R A2 The alkyl group having 1 to 12 carbon atoms represented by R A1 The alkyl group may be any of those listed as m 2 is preferably 0 or 1, and more preferably 0. When the epoxy resin is a mixture of resins with different numbers of structural units in parentheses, n represents the average value of the mixture. n is preferably 2 to 10.

[0035] [ka]

[0036] In formula (a1-2), R A1 and m 1 is R in formula (a) A1 and m 1 is the same as

[0037] Commercially available epoxy resins (a1) include, for example, dicyclopentadiene-type epoxy resins such as XD-1000 (trade name, manufactured by Nippon Kayaku Co., Ltd.), EPICLON HP-7200L, EPICLON HP-7200, EPICLON HP-7200HH, and EPICLON HP-7200HHH (trade names, manufactured by DIC Corporation, "EPICLON" is a registered trademark).

[0038] As the component (A2), for example, an addition reaction product obtained by adding a saturated or unsaturated polybasic acid anhydride (c) to an ester obtained by reacting an epoxy resin (a2) not having an alicyclic skeleton with a vinyl group-containing monocarboxylic acid (b) can be used.

[0039] Examples of the epoxy resin (a2) include bisphenol-based epoxy resins such as bisphenol A epoxy resins, bisphenol F epoxy resins, and bisphenol S epoxy resins; bisphenol-based novolac epoxy resins such as bisphenol A novolac epoxy resins and bisphenol F novolac epoxy resins; phenol aralkyl epoxy resins; stilbene epoxy resins; naphthalene skeleton-containing epoxy resins such as naphthalene epoxy resins, naphthol novolac epoxy resins, naphthol epoxy resins, naphthol aralkyl epoxy resins, and naphthylene ether epoxy resins; biphenyl epoxy resins; biphenyl aralkyl epoxy resins; xylylene epoxy resins; dihydroanthracene epoxy resins; and aliphatic chain epoxy resins. Among these, bisphenol-based novolac epoxy resins are preferred, and bisphenol F novolac epoxy resins are more preferred.

[0040] The acid value of component (A) is not particularly limited. From the viewpoint of improving the solubility of the unexposed area in an alkaline aqueous solution, the acid value of component (A) may be 30 mgKOH / g or more, 40 mgKOH / g or more, or 50 mgKOH / g or more. From the viewpoint of improving the electrical properties of the cured product, the acid value of component (A) may be 150 mgKOH / g or less, 120 mgKOH / g or less, or 100 mgKOH / g or less.

[0041] The weight average molecular weight (Mw) of component (A) may be 3500 or less, 3000 or less, 2500 or less, or 2000 or less from the viewpoint of further reducing residue at the bottom of via formation, and may be 500 or more, or 1000 or more from the viewpoint of ensuring developability during development.

[0042] The Mw of component (A) can be measured by gel permeation chromatography (GPC). For example, Mw can be measured under the following GPC conditions, and the value converted using a calibration curve of standard polystyrene can be used as Mw. The calibration curve can be created using a five-sample set ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) as standard polystyrene.

[0043] (GPC conditions) GPC equipment: High-speed GPC equipment "HCL-8320GPC" (Tosoh Corporation) Detector: Differential refractometer or UV detector (Tosoh Corporation) Column: TSKgel SuperMultipore HZH column (column length: 15 cm, column inner diameter: 4.6 mm) (manufactured by Tosoh Corporation) Eluent: tetrahydrofuran (THF) Measurement temperature: 40℃ Flow rate: 0.35mL / min Sample concentration: 10 mg / 5 mL of THF Injection volume: 20μL

[0044] In the (A) component, the content of the (A1) component may be 80 mass % or more, 90 mass % or more, or 95 mass % or more, based on the total amount of the (A) component, from the viewpoint of further reducing residue at the bottom of the via when the via is formed, and may be substantially 100 mass %.

[0045] The content of the component (A) in the photosensitive resin composition may be 50 mass % or less, 45 mass % or less, or 42 mass % or less, based on the total solid content of the photosensitive resin composition, from the viewpoint of further reducing residue at the bottom of vias during via formation, and may be 20 mass % or more, 30 mass % or more, or 40 mass % or more, based on the total solid content of the photosensitive resin composition, from the viewpoint of ensuring developability during development.

[0046] ((B) component: thermosetting resin) The photosensitive resin composition according to this embodiment contains a thermosetting resin as component (B). By including component (B), a cured product with excellent adhesiveness can be formed. The component (B) may be used alone or in combination of two or more.

[0047] Examples of component (B) include epoxy resins, phenolic resins, unsaturated imide resins, cyanate resins, isocyanate resins, benzoxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, dicyclopentadiene resins, silicone resins, triazine resins, and melamine resins. Among these, epoxy resins are preferred from the viewpoint of superior adhesiveness of the cured product.

[0048] Examples of epoxy resins include bisphenol-type epoxy resins such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and bisphenol S-type epoxy resins; novolac-type epoxy resins such as bisphenol-based novolac-type epoxy resins, phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, and biphenyl novolac-type epoxy resins; phenol aralkyl-type epoxy resins; stilbene-type epoxy resins; naphthalene skeleton-containing epoxy resins such as naphthalene-type epoxy resins, naphthol novolac-type epoxy resins, naphthol-type epoxy resins, naphthol aralkyl-type epoxy resins, and naphthylene ether-type epoxy resins; biphenyl-type epoxy resins; biphenyl aralkyl-type epoxy resins; xylylene-type epoxy resins; dihydroanthracene-type epoxy resins; alicyclic epoxy resins such as dicyclopentadiene-type epoxy resins; heterocyclic epoxy resins; spiro ring-containing epoxy resins; cyclohexane dimethanol-type epoxy resins; trimethylol-type epoxy resins; aliphatic linear epoxy resins; and rubber-modified epoxy resins.

[0049] Among these, from the viewpoints of achieving superior heat resistance, adhesiveness, and electrical insulation reliability of the cured product, and further reducing residue at the bottom of vias when they are formed, it is preferable to use at least one epoxy resin selected from bisphenol-type epoxy resins, phenol novolac-type epoxy resins, naphthol-type epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, naphthylene ether-type epoxy resins, and cresol novolac-type epoxy resins.

[0050] The content of component (B) in the photosensitive resin composition may be 2 to 30 mass%, 5 to 25 mass%, or 8 to 20 mass%, based on the total solid content of the photosensitive resin composition. When the content of component (B) is within the above range, good developability can be maintained while the heat resistance of the formed cured film can be further improved.

[0051] (Component (C): Photopolymerization initiator) The photosensitive resin composition according to this embodiment contains a photopolymerization initiator as component (C). There are no particular limitations on component (C) as long as it can polymerize component (D) and the like.

[0052] Examples of component (C) include benzoin compounds such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propane, N,N acetophenone compounds such as 2-dimethylaminoacetophenone; anthraquinone compounds such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, and 2-aminoanthraquinone; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal. Compounds: benzophenone compounds such as benzophenone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, Michler's ketone, and 4-benzoyl-4'-methyldiphenyl sulfide; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, and 2-(o-methoxyphenyl) Imidazole compounds such as 4,5-diphenylimidazole dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4-di(p-methoxyphenyl)-5-phenylimidazole dimer, and 2-(2,4-dimethoxyphenyl)-4,5-diphenylimidazole dimer; acridine compounds such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide;Examples of suitable oxime ester compounds include 1-[4-(phenylthio)phenyl]octane-1,2-dione-2-(O-benzoyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime), and 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime]; and tertiary amine compounds such as N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine.

[0053] Component (C) may be used alone or in combination of two or more. When two or more are used in combination, a combination of an acetophenone compound, a thioxanthone compound, and an oxime ester compound is preferred, and a combination of 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4-diethylthioxanthone, and 1-[4-(phenylthio)phenyl]octane-1,2-dione-2-(O-benzoyloxime) is more preferred.

[0054] The content of component (C) in the photosensitive resin composition is not particularly limited, and may be 0.1 to 15 mass%, 0.5 to 5 mass%, 0.8 to 3 mass%, or 1 to 1.5 mass% based on the total solid content of the photosensitive resin composition. When the content of component (C) is 0.1 mass% or more, elution of exposed areas during development when forming a resist pattern tends to be easily suppressed, and when the content of component (C) is 15 mass% or less, the heat resistance of the cured product tends to be easily improved.

[0055] ((D) component: photopolymerizable compound) The photosensitive resin composition according to this embodiment contains a photopolymerizable compound (excluding compounds that fall under the category of (A) acid-modified vinyl group-containing resin) as component (D) from the viewpoint of suppressing undercut while exhibiting excellent developability. Component (D) is a (meth)acrylic monomer having 5 to 10 (meth)acrylic groups and 0 to 24 ethylene oxide chains. Hereinafter, this (meth)acrylic monomer will also be referred to as component (D1). The number of ethylene oxide chains refers to the total number of ethylene oxide chains (structure of formula (1) below) present in the compound structure. [ka]

[0056] The present inventors speculate that the reason why a photosensitive resin composition containing as component (D) a (meth)acrylic monomer having 5 to 10 (meth)acrylic groups and 0 to 24 ethylene oxide chains can suppress undercut while maintaining excellent developability is as follows: That is, by setting the number of (meth)acrylic groups to a specific number or more, the insolubility of the exposed portions increases due to curing, which promotes curing of the bottom portions and suppresses undercut; and by setting the number of ethylene oxide chains to a specific number or less, the distance between crosslinks of the polymer crosslinked by exposure becomes shorter, bringing the developable groups closer to each other, thereby ensuring developability. However, the mechanism of the present invention is not limited to the above.

[0057] From the viewpoint of easily achieving better developability, the number of (meth)acrylic groups in the component (D1) may be 5 to 8, 5 to 7, or 5 to 6. From the viewpoint of easily suppressing undercut, the number of (meth)acrylic groups in the component (D1) may be 6 to 10, 8 to 10, or 9 to 10.

[0058] From the viewpoint of easily achieving superior developability, the maximum value of the number of (meth)acrylic groups in the component (D1) (maximum number of (meth)acrylic groups) may be 6 to 10, 6 to 8, or 6. From the viewpoint of easily suppressing undercut, the maximum value of the number of (meth)acrylic groups in the component (D1) (maximum number of (meth)acrylic groups) may be 6 to 10, 8 to 10, or 10.

[0059] From the viewpoint of easily achieving better developability, the number of ethylene oxide chains in the component (D1) may be 6 to 24, 12 to 24, or 18 to 24. From the viewpoint of easily suppressing undercut, the number of ethylene oxide chains in the component (D1) may be 0 to 18, 0 to 12, or 0 to 6.

[0060] The component (D1) may be a compound having the structure of the following formula (2). [ka] [In formula (2), R 1 ~R 6 each represents an ethylene oxide group, and R 7 represents a hydrogen atom or an acrylic group, and a to f are integers of 0 or more, the sum of a to f is 0 to 24, and when a to f are 0, the ethylene group and the oxygen atom are directly bonded.]

[0061] In formula (2), from the viewpoint of easily achieving better developability, the total of a to f may be 6 to 24, 12 to 24, or 18 to 24. In formula (2), from the viewpoint of easily suppressing undercut, the total of a to f may be 0 to 18, 0 to 12, or 0 to 6.

[0062] The molecular weight of component (D1) (when the number of (meth)acrylic groups is at its maximum) may be 300 to 3000, 400 to 2000, or 500 to 1800, from the viewpoints of easily achieving better developability and more easily suppressing undercut. When the molecular weight of component (D1) is 300 or more, the solubility of the photosensitive resin composition is prevented from increasing, making it easier to suppress undercut. When the molecular weight is 3000 or less, developability is further improved.

[0063] From the viewpoint of easily achieving better developability and more easily suppressing undercut, the component (D1) may be at least one selected from the group consisting of dipentaerythritol hexa(meth)acrylate, ethoxylated dipentaerythritol poly(meth)acrylate, ethoxylated dipentaerythritol poly(meth)acrylate, and polypentaerythritol (meth)acrylate.

[0064] The component (D) may contain a component other than the component (D1) (hereinafter, this component may also be referred to as the component (D2)). Examples of the component (D2) include a photopolymerizable compound having one ethylenically unsaturated group, a photopolymerizable compound having two ethylenically unsaturated groups, and a photopolymerizable compound having three or more ethylenically unsaturated groups.

[0065] Examples of photopolymerizable compounds having one ethylenically unsaturated group include (meth)acrylic acid and (meth)acrylic acid alkyl esters. Examples of (meth)acrylic acid alkyl esters include (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid butyl ester, (meth)acrylic acid 2-ethylhexyl ester, and (meth)acrylic acid hydroxylethyl ester.

[0066] Examples of photopolymerizable compounds having two ethylenically unsaturated groups include polyethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, polypropylene glycol di(meth)acrylate, 2,2-bis(4-(meth)acryloxypolyethoxypolypropoxyphenyl)propane, and bisphenol A diglycidyl ether di(meth)acrylate.

[0067] Examples of photopolymerizable compounds having three or more ethylenically unsaturated groups include (meth)acrylate compounds having a skeleton derived from trimethylolpropane, such as trimethylolpropane tri(meth)acrylate; (meth)acrylate compounds having a skeleton derived from tetramethylolmethane, such as tetramethylolmethane tri(meth)acrylate and tetramethylolmethane tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from ditrimethylolpropane, such as ditrimethylolpropane tetra(meth)acrylate; and (meth)acrylate compounds having a skeleton derived from diglycerin.

[0068] The content of the component (D1) may be 1% by mass or more, 3% by mass or more, 5% by mass or more, or 6% by mass or more, based on the total solid content of the photosensitive resin composition, from the viewpoints of easily achieving better developability and more easily suppressing undercut, and from the same viewpoints, it may be 20% by mass or less, 15% by mass or less, 10% by mass or less, or 8% by mass or less. From the same viewpoints, the content of the component (D1) may be 1 to 20% by mass, 3 to 15% by mass, 5 to 10% by mass, or 6 to 8% by mass, based on the total solid content of the photosensitive resin composition.

[0069] From the viewpoint of easily achieving better developability and more easily suppressing undercut, the content of the component (D1) in the component (D) may be 50% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more, based on the total amount of the component (D), or may be 100% by mass (an embodiment in which the component (D) consists essentially of the component (D1)).

[0070] The content of component (D) may be 1% by mass or more, 3% by mass or more, 5% by mass or more, or 6% by mass or more, based on the total solid content of the photosensitive resin composition, from the viewpoint of easily achieving better developability and more easily suppressing undercut, and from the same viewpoint, may be 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass or less. From the same viewpoint, the content of component (D) may be 1 to 30% by mass, 3 to 25% by mass, 5 to 20% by mass, or 6 to 15% by mass, based on the total solid content of the photosensitive resin composition.

[0071] (Component (E): inorganic filler) The photosensitive resin composition according to this embodiment may further contain an inorganic filler as component (E). By containing component (E), the adhesiveness, reliability, etc. of the cured product can be improved. The component (E) may be used alone or in combination of two or more.

[0072] Examples of inorganic fillers include silica, alumina, titania, tantalum oxide, zirconia, silicon nitride, barium titanate, barium carbonate, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, lead titanate, lead zirconate titanate, lead lanthanum zirconate titanate, gallium oxide, spinel, mullite, cordierite, talc, aluminum titanate, yttria-containing zirconia, barium silicate, boron nitride, calcium carbonate, barium sulfate, calcium sulfate, zinc oxide, magnesium titanate, hydrotalcite, mica, calcined kaolin, and carbon.

[0073] Component (E) may contain silica to improve the heat resistance of the cured product, and may contain barium sulfate to improve the heat resistance and adhesiveness of the cured product. To improve the dispersibility of the inorganic filler, an inorganic filler that has been surface-treated with alumina or an organic silane compound may be used.

[0074] From the viewpoint of developability, the average particle size of the inorganic filler is preferably from 0.01 to 5.0 μm, more preferably from 0.1 to 3.0 μm, even more preferably from 0.3 to 2.0 μm, and particularly preferably from 0.5 to 1.5 μm.

[0075] When the photosensitive resin composition of this embodiment contains component (E), the content thereof may be 5 to 80 mass%, 10 to 60 mass%, 15 to 50 mass%, 20 to 45 mass%, 25 to 40 mass%, or 30 to 40 mass%, based on the total solid content of the photosensitive resin composition. When the content of component (E) is within the above range, it is possible to improve the developability, the mechanical strength and heat resistance of the cured product, etc.

[0076] (Component (F): Pigment) The photosensitive resin composition of this embodiment may further contain a pigment as component (F) from the viewpoint of improving the distinguishability or appearance of the production equipment. As component (F), a colorant that develops a desired color when concealing wiring, etc., can be used. Examples of component (F) include phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black.

[0077] From the viewpoint of further concealing the wiring, the content of the component (F) may be 0.1 to 10 mass %, 0.1 to 5 mass %, or 0.1 to 1 mass % based on the total amount of solids in the photosensitive resin composition.

[0078] (Other ingredients) The photosensitive resin composition according to this embodiment may further contain various additives as needed, such as a thermal polymerization initiator, a polymerization inhibitor such as hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, or pyrogallol, a thickener such as bentone or montmorillonite, a silicone-based, fluorine-based, or vinyl resin-based defoaming agent, a silane coupling agent, a flame retardant such as a brominated epoxy compound, an acid-modified brominated epoxy compound, an antimony compound, a phosphate compound, an aromatic condensed phosphate ester, or a halogen-containing condensed phosphate ester, and a thermoplastic resin such as a polyester polyurethane resin.

[0079] (solvent) The photosensitive resin composition according to this embodiment may contain a solvent as needed. The photosensitive resin composition according to this embodiment contains a solvent for dissolving and dispersing each component, which makes it easy to apply the composition to a substrate and allows the formation of a coating film with a uniform thickness, thereby enabling the formation of a more precise pattern.

[0080] Examples of the solvent include organic solvents. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, propylene glycol monoethyl ether acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; and petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. Among these, ketones and esters are preferred, and esters are more preferred. The solvents may be used alone or in combination of two or more.

[0081] The amount of the solvent to be added may be appropriately selected so that the concentration of the total solid content in the photosensitive resin composition is 40 to 90 mass %, 45 to 80 mass %, or 45 to 70 mass %.

[0082] The photosensitive resin composition of this embodiment can be prepared by uniformly mixing the above-described components using a roll mill, a bead mill, etc. The photosensitive resin composition of this embodiment may be used in a liquid state, or in a film state, such as the photosensitive element described below.

[0083] [Photosensitive element] The photosensitive element according to this embodiment includes a support film and a photosensitive layer containing the above-described photosensitive resin composition. FIG. 1 is a cross-sectional view schematically illustrating the photosensitive element according to this embodiment. As shown in FIG. 1, the photosensitive element 1 includes a support film 10 and a photosensitive layer 20 formed on the support film 10. The photosensitive element 1 may further include a protective film 30 on the photosensitive layer 20.

[0084] The photosensitive element 1 can be produced by applying the photosensitive resin composition according to this embodiment onto a support film 10 using a known coating device such as a comma coater, bar coater, kiss coater, roll coater, gravure coater, or die coater, and then drying the coating to form a photosensitive layer 20. The thickness of the photosensitive layer is not particularly limited, but may be 1 to 100 μm, 1 to 50 μm, or 5 to 40 μm from the viewpoint of thinning the printed wiring board.

[0085] The coating film can be dried using a hot air dryer, a dryer using far-infrared rays or near-infrared rays, or the like. The drying temperature may be 60 to 150°C, 70 to 120°C, or 80 to 100°C. The drying time may be 1 to 60 minutes, 2 to 30 minutes, or 5 to 20 minutes. The content of residual solvent in the dried coating film may be 3% by mass or less, 2% by mass or less, or 1% by mass or less, from the viewpoint of avoiding diffusion of the solvent during the manufacturing process of the printed wiring board.

[0086] Examples of the support film include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film, and polyolefin films such as polypropylene film and polyethylene film. The thickness of the support film may be, for example, 5 to 100 μm, 5 to 60 μm, or 15 to 45 μm.

[0087] For example, a polymer film such as polyethylene or polypropylene may be used as the protective film 30. The protective film 30 may be the same as or different from the support film 10.

[0088] The photosensitive resin composition according to this embodiment is suitable as a permanent resist for an interlayer insulating layer of a printed wiring board, etc. The photosensitive resin composition according to this embodiment is also useful for forming a cavity for incorporating a chip, a passive element, etc. The photosensitive resin composition according to this embodiment is also useful for forming a surface protection layer of a printed wiring board.

[0089] [Printed wiring board] The printed wiring board according to this embodiment includes an interlayer insulating layer containing a cured product of the photosensitive resin composition according to this embodiment.

[0090] The method for manufacturing a printed wiring board according to this embodiment includes the steps of forming a photosensitive layer on a substrate using the photosensitive resin composition or photosensitive element according to this embodiment, exposing and developing the photosensitive layer to form a resist pattern, and curing the resist pattern to form an interlayer insulating layer.

[0091] FIG. 2 is a schematic cross-sectional view showing an example of a method for manufacturing a multilayer printed wiring board having an interlayer insulating layer made of a cured product of the photosensitive resin composition according to this embodiment. Multilayer printed wiring board 100A shown in FIG. 2(f) has wiring patterns on its surface and inside. Multilayer printed wiring board 100A can be obtained by laminating a copper clad laminate, an interlayer insulating layer, a metal foil, etc., and then appropriately forming a wiring pattern by an etching method or a semi-additive method. The method for manufacturing multilayer printed wiring board 100A will be briefly described below with reference to FIG. 2.

[0092] First, interlayer insulating layers 103 are formed on both sides of a substrate (e.g., a copper-clad laminate) 101 having a wiring pattern 102 on its surface (see (a) of FIG. 2). The interlayer insulating layer 103 may be formed by printing the photosensitive resin composition according to this embodiment using a screen printer or a roll coater, or it may be formed by preparing a photosensitive element according to this embodiment in advance and attaching the photosensitive layer of the photosensitive element to the surface of the substrate 101 using a laminator.

[0093] Next, vias (openings) 104 are formed using a YAG laser or a carbon dioxide laser in locations that require electrical connection to the outside (see FIG. 2(b)). Smears (residues) around the vias 104 can be removed by desmearing.

[0094] Next, a seed layer 105 is formed by electroless plating (see FIG. 2(c)). A photosensitive layer containing a photosensitive resin composition is formed on the seed layer 105, and predetermined locations are exposed and developed to form a resin pattern 106 (see FIG. 2(d)).

[0095] Next, by electrolytic plating, a wiring pattern 107 is formed on the portion of the seed layer 105 where the resin pattern 106 is not formed. Then, after removing the resin pattern 106 with a stripping liquid, the portion of the seed layer 105 where the wiring pattern 107 is not formed is removed by etching (see (e) of FIG. 2).

[0096] The above-mentioned operations are repeated to form a solder resist 108 containing a cured product of the photosensitive resin composition according to this embodiment on the outermost surface, thereby producing a multilayer printed wiring board 100A (see FIG. 2(f)). For example, semiconductor elements can be mounted in corresponding locations on the multilayer printed wiring board 100A obtained in this manner, ensuring electrical connection.

[0097] The photosensitive resin composition according to this embodiment can be used to produce a semiconductor element having an interlayer insulating layer formed from a cured product of the photosensitive resin composition, and an electronic device including the semiconductor element. The semiconductor element may be, for example, a memory, a package, or the like having a multilayer wiring structure, a rewiring structure, or the like. Examples of electronic devices include mobile phones, smartphones, tablet terminals, personal computers, and hard disk suspensions. By providing a patterned cured product formed from the photosensitive resin composition according to this embodiment, semiconductor elements and electronic devices with excellent reliability can be provided. [Example]

[0098] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to these examples.

[0099] (Synthesis of acid-modified vinyl group-containing resin) 250 parts by mass of dicyclopentadiene-type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., trade name "XD-1000"), 70 parts by mass of acrylic acid, 0.5 parts by mass of methylhydroquinone, and 120 parts by mass of carbitol acetate were mixed with stirring at 90°C. The mixed solution was cooled to 60°C, and 2 parts by mass of triphenylphosphine was added. The mixture was reacted at 100°C until the acid value of the solution reached 1 mgKOH / g. 98 parts by mass of tetrahydrophthalic anhydride and 850 parts by mass of carbitol acetate were added to the reaction solution, and the mixture was heated to 80°C and reacted for 6 hours. The reaction solution was then cooled to room temperature to obtain a solution of acid-modified epoxy acrylate resin (solids concentration 65% by mass) as component (A). The Mw of the resulting acid-modified epoxy acrylate resin was 1,800.

[0100] The following materials were prepared as components (A) to (F). A-1: Acid-modified epoxy acrylate resin synthesized above B-1: Tetramethylbiphenol type epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "YX4000") C-1: 1-[4-(phenylthio)phenyl]octane-1,2-dione-2-(O-benzoyloxime) (manufactured by BASF, trade name "Irgacure OXE01") C-2: 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propane (manufactured by IGM Resins BV, trade name "Omnirad 907") C-3: 2,4-diethylthioxanthone (manufactured by Nagase & Co., Ltd., trade name "SB-PI799") D-1: Dipentaerythritol hexaacrylate (manufactured by Tokyo Chemical Industry Co., Ltd., trade name "DPHA") D-2: Ethoxylated dipentaerythritol polyacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "A-DPH-12E") D-3: Ethoxylated dipentaerythritol polyacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "A-DPH-24E") D-4: Polypentaerythritol acrylate (Osaka Organic Chemical Industry Co., Ltd., trade name "TriPEA") D-5: Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "A-TMMT") D-6: Ethoxylated pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "ATM-35E") D-7: Ditrimethylolpropane tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "AD-TMP") D-8: Ethoxylated dipentaerythritol polyacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "A-DPH-48E") D-9: Trimethylolpropane triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name "A-TMPT") E-1: Silica (average particle size 0.5 μm) (manufactured by Admatechs Co., Ltd., ADMAFINE (registered trademark)) F-1: Phthalocyanine dye (manufactured by Sanyo Pigment Co., Ltd.)

[0101] [Photosensitive resin composition] The components were blended in the amounts (parts by mass, solid content equivalent) shown in Table 1 and kneaded using a three-roll mill. Then, carbitol acetate was added so that the solid content concentration became 60% by mass, thereby preparing a photosensitive resin composition.

[0102] [Photosensitive element] A 16 μm-thick polyethylene terephthalate film (manufactured by Teijin Limited, product name "G2-16") was prepared as a support film. A photosensitive resin composition was applied to the support film so that the thickness after drying would be 18 μm, and the composition was dried at 75°C for 30 minutes using a hot air convection dryer to form a photosensitive layer. Next, a polyethylene film (manufactured by Tamapoly Corporation, product name "NF-15") was attached as a protective film to the surface of the photosensitive layer opposite the side in contact with the support film, thereby obtaining a photosensitive element.

[0103] [Evaluation of developability] The protective film was peeled off from the photosensitive element produced in each example, and the exposed photosensitive layer was laminated onto a 0.6 mm thick copper-clad laminate substrate (manufactured by Resonac Inc., product name "MCL-E-67") using a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500") at 80°C to obtain a laminate having a photosensitive layer with a carrier film. Next, a negative mask having a via pattern with predetermined opening diameters (opening mask diameter sizes: 20, 50 μm) was attached to the carrier film of the laminate, and the laminate was exposed using an ultraviolet exposure device with an exposure dose sufficient to achieve 10 complete curing steps on a step tablet (manufactured by Resonac Inc.). Next, the carrier film was peeled off from the photosensitive layer, and the photosensitive layer was cured for 60 seconds using a 1% by weight aqueous sodium carbonate solution at 1.765 × 10 5 The unexposed areas were then developed by spraying at a pressure of 2,000 mJ / cm using an ultraviolet exposure device.2 After the photosensitive layer was exposed to an exposure dose of 1000 ppm, it was heated at 170°C for 1 hour to prepare a test piece having a permanent mask resist with an opening pattern formed on a copper-clad laminate substrate. The test piece was observed using an optical microscope to confirm the top opening diameter and bottom opening diameter when the opening diameter size was 20 µm, and evaluated according to the following criteria. <Evaluation criteria for top opening diameter> A: The via was opened and the top diameter was 15 μm or more. B: The via was opened and the top diameter was less than 15 μm. C: The via did not open. <Evaluation criteria for bottom opening diameter> A: The via was opened and the top diameter was 11 μm or more. B: The via was opened and the top diameter was less than 11 μm. C: The via did not open.

[0104] [Undercut evaluation] The test pieces prepared in the "Evaluation of developability" section above were cast in an embedding resin (using Mitsubishi Chemical Corporation's trade name "jER828" as the epoxy resin and triethylenetetramine as the curing agent) and allowed to fully harden. After that, they were polished with a polishing machine (Refine Tech Co., Ltd.'s trade name "Refine Polisher") to remove the cross section of the opening pattern of the permanent mask resist. The cross section of the resulting opening pattern was observed using a metallurgical microscope, and the amount of undercut when the opening diameter size was 50 μm was evaluated according to the following criteria. <Evaluation criteria> A: The via was opened and the amount of undercut was less than 1.0 μm. B: The via was opened, and the amount of undercut was 1.0 μm or more and less than 3.5 μm. C: The via was opened and the amount of undercut was 3.5 μm or more.

[0105] [Table 1]

[0106] [Table 2] [Explanation of symbols]

[0107] 1...photosensitive element, 10...support film, 20...photosensitive layer, 30...protective film, 100A...multilayer printed wiring board, 101...substrate, 102, 107...wiring pattern, 103...interlayer insulating layer, 104...via, 105...seed layer, 106...resin pattern, 108...solder resist.

Claims

1. (A) an acid-modified vinyl group-containing resin; (B) a thermosetting resin; (C) a photopolymerization initiator; and (D) a photopolymerizable compound (excluding compounds corresponding to the acid-modified vinyl group-containing resin (A)); The photosensitive resin composition, wherein the (D) photopolymerizable compound contains a (meth)acrylic monomer having 5 to 10 (meth)acrylic groups and 0 to 24 ethylene oxide chains.

2. The photosensitive resin composition according to claim 1 , wherein the number of the (meth)acrylic groups is 5 or 6.

3. 2. The photosensitive resin composition according to claim 1, wherein the number of ethylene oxide chains is 0 to 6.

4. 2. The photosensitive resin composition according to claim 1, wherein the number of ethylene oxide chains is 12 to 24.

5. The photosensitive resin composition according to claim 1 , wherein the acid-modified vinyl group-containing resin (A) has a dicyclopentadiene skeleton.

6. The photosensitive resin composition according to claim 1 , further comprising (E) an inorganic filler.

7. The photosensitive resin composition according to claim 6, wherein the inorganic filler (E) is silica.

8. The photosensitive resin composition according to claim 1 , further comprising (F) a pigment.

9. A support film and a photosensitive layer formed on the support film, A photosensitive element, wherein the photosensitive layer comprises the photosensitive resin composition according to any one of claims 1 to 8.

10. A printed wiring board comprising an interlayer insulating layer containing a cured product of the photosensitive resin composition according to any one of claims 1 to 8.

11. forming a photosensitive layer on a substrate using the photosensitive resin composition according to any one of claims 1 to 8; exposing and developing the photosensitive layer to form a resist pattern; hardening the resist pattern to form an interlayer insulating layer; A method for manufacturing a printed wiring board, comprising:

12. forming a photosensitive layer on a substrate using the photosensitive element of claim 9; exposing and developing the photosensitive layer to form a resist pattern; hardening the resist pattern to form an interlayer insulating layer; A method for manufacturing a printed wiring board, comprising:

Images