Photosensitive resin composition and photosensitive element

Abstract

One of the purposes of the present invention is to provide a photosensitive resin composition which is reduced in a side etch amount, can exhibit excellent uniformity in copper line widths, can be promoted with respect to the development of color of a dye contained therein upon exposure to light, and can have a light-exposed part having excellent visibility. According to the present invention, a photosensitive resin composition is provided, which comprises (A) an alkali-soluble polymer, (B) a compound having an ethylenically unsaturated double bond, (C) a photopolymerization initiator, (D) a dye and (E) a compound represented by the general formula shown below (wherein each of R1 and R2 does not have an amino group and is independently selected from the group consisting of a hydrogen atom and an organic group having 1 to 20 carbon atoms, wherein at least one of R1 and R2 has an acidic group having a pKa value of 5 or less).

Description

Photosensitive resin composition and photosensitive element

[0001] The present invention relates to a photosensitive resin composition and a photosensitive element.

[0002] Printed wiring boards are generally manufactured by photolithography, which is a method of forming a desired wiring pattern on a substrate by forming a layer made of a photosensitive resin composition on the substrate, exposing the coating to light and developing the pattern to form a resist pattern, etching or plating to form a conductor pattern, and then removing the resist pattern on the substrate.

[0003] In the manufacture of printed wiring boards, a photosensitive element (dry film resist) in which a photosensitive resin layer is laminated on a support is often used. Many known examples of methods for forming wiring patterns using such photosensitive elements and photosensitive resin compositions suitable for such methods are available, including, for example, Patent Documents 1 to 5 listed below.

[0004] Patent Document 1 aims to provide a photosensitive resin composition that is highly sensitive, particularly to ultraviolet light and visible light, and can be cured by laser drawing, and that has excellent storage stability after film formation on a substrate and after drawing. As a solution to this problem, Patent Document 1 describes a photosensitive resin composition containing tetrazole or a derivative thereof, or triazole or a derivative thereof. Examples of tetrazole or a derivative thereof include 1H-1,2,3,4-tetrazole, 5-amino-1H-tetrazole, and 5-methyl-1H-tetrazole, and examples of triazole or a derivative thereof include 1,2,4-triazole or 5-chlorobenzotriazole.

[0005] Patent Document 2 aims to provide a photosensitive resin composition that can form an extremely stable resist film that has excellent adhesion to copper surfaces and is not affected by changes over time after coating or lamination. As a solution to this problem, Patent Document 2 describes a photosensitive resin composition that contains one or more heterocyclic compounds selected from the group consisting of triazoles, tetrazoles, and imidazoles.

[0006] Patent Document 3 aims to provide a photosensitive resin composition that has high sensitivity, can obtain a good resist pattern shape, has strong tent film strength, and can form a high-definition pattern with a high aspect ratio. As a solution to this problem, Patent Document 3 describes a photosensitive resin composition containing a monocarboxylic acid compound having a molecular weight of 180 to 2,000.

[0007] Patent Document 4 aims to provide a photosensitive resin composition that can fragment peeled pieces (reducing the size of peeled resist pieces), has excellent plating resistance, sensitivity, resolution, and adhesion, and as a solution to this problem, Patent Document 4 describes a photosensitive resin composition that contains a binder polymer containing at least (meth)acrylic acid and a hydroxyalkyl (meth)acrylic acid ester as copolymerization components, and further contains benzotriazole and a carboxybenzotriazole derivative represented by a specific general formula as an adhesion promoter.

[0008] Patent Document 5 aims to provide a photosensitive resin composition that can form a resist that has sufficiently excellent adhesion to a conductor layer and is less likely to cause discoloration of the conductor layer. As a solution to this problem, Patent Document 5 describes a photosensitive resin composition that includes a binder polymer, a photopolymerizable compound having an ethylenically unsaturated group, a photopolymerization initiator, and a benzotriazole derivative represented by a specific general formula:

[0009] Japanese Patent Application Laid-Open No. 2002-317005 Japanese Patent No. 4883537 Japanese Patent Application Laid-Open No. 2011-81391 Japanese Patent Application Laid-Open No. 2010-72535 Japanese Patent No. 4449983

[0010] In recent years, with the miniaturization and weight reduction of electronic devices, the miniaturization and density of printed wiring boards have progressed, and there is a demand for high-performance photosensitive elements that can reduce side etching (hereinafter also simply referred to as "side etch") in the manufacturing process of photosensitive elements and provide more uniform copper line widths. Furthermore, photosensitive elements generally contain a dye so that the resist pattern formed on the copper foil can be seen with good contrast after development. The dye has the function of changing the color of the exposed portion when the DF is exposed.

[0011] An object of the present invention is to provide a photosensitive resin composition that reduces the amount of side etching, provides excellent uniformity in copper line width, promotes color development of a dye upon exposure, and provides excellent visibility of the exposed area.

[0012] As a result of extensive research to solve the above problems, the present inventors have found that the above problems can be solved by a photosensitive resin composition containing an alkali-soluble polymer, a compound having an ethylenically unsaturated double bond, a photopolymerization initiator, a dye, and a compound having a specific structure, and have completed the present invention. That is, the present invention is as follows: [1] (A) an alkali-soluble polymer, (B) a compound having an ethylenically unsaturated double bond, (C) a photopolymerization initiator, (D) a dye, and (E) a compound represented by the following general formula (3): {In the formula, R １ and R ２ are each independently selected from the group consisting of a hydrogen atom or an organic group having 1 to 20 carbon atoms, and do not have an amino group, provided that R １ and R ２ wherein at least one of R has an acidic group with a pKa of 5 or less. １ and R ２ are each independently selected from the group consisting of a hydrogen atom or an organic group having 1 to 3 carbon atoms, and do not have an amino group, provided that R １ and R ２ [3] The photosensitive resin composition according to item 1, wherein at least one of R １ and R ２None of the groups has an amino group, and R １ and R ２ and the other is a hydrogen atom. [4] The photosensitive resin composition according to any one of items 1 to 3, wherein the acidic group is a carboxy group, a phosphate group, or a sulfonic acid group. [5] The photosensitive resin composition according to item 4, wherein the acidic group is a carboxy group. [6] The photosensitive resin composition according to any one of items 1 to 5, wherein the dye (D) is a leuco dye. [7] The photosensitive resin composition according to any one of items 1 to 6, wherein the compound (E) is contained in an amount of 0.001 to 0.5 mass% based on the total amount of solids in the photosensitive resin composition. [8] The photosensitive resin composition according to any one of items 1 to 7, wherein the compound (E) is a solid at 25°C. [9] The photosensitive resin composition according to any one of items 1 to 8, wherein the alkali-soluble polymer (A) contains an aromatic ring in its molecular structure.

[10] A photosensitive element comprising a support and a layer of the photosensitive resin composition according to any one of items 1 to 9 formed on the support.

[0013] According to the present invention, it is possible to provide a photosensitive resin composition that reduces the amount of side etching, provides excellent uniformity in copper line width, promotes color development of dyes upon exposure, and provides excellent visibility of exposed areas. Note that the above description should not be construed as disclosing all embodiments of the present invention and all advantages of the present invention. Further embodiments and advantages of the present invention will become apparent from the following description.

[0014] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail for the purpose of illustrating the present invention, but the present invention is not limited to the present embodiment. In the present specification, the upper and lower limits of each numerical range can be combined arbitrarily.

[0015] [Photosensitive Resin Composition] The photosensitive resin composition of this embodiment contains (A) an alkali-soluble polymer, (B) a compound having an ethylenically unsaturated double bond, (C) a photopolymerization initiator, (D) a dye, and (E) a compound having a specific heterocyclic structure. Compound (E) is a compound represented by the general formula (3) described below. By virtue of the above-described configuration, the photosensitive resin composition of this embodiment can provide a photosensitive resin composition that reduces the amount of side etching, provides excellent uniformity in copper line width, promotes dye color development upon exposure, and provides excellent visibility of exposed areas. The reason for this is not yet clear, and the present invention is not limited by theory, but the inventors speculate as follows: The adhesion and reactivity between the cured resist and the copper interface are important for reducing the amount of side etching. During the etching process, the etchant penetrates into the resist-copper interface, resulting in a difference (side etch) between the line width of the dry film and the copper line width after etching. Strong interaction at the resist-copper interface makes it difficult for the etchant to penetrate, reducing the amount of side etching. Imidazole, triazole, and tetrazole are known compounds that interact strongly with copper. However, their high hydrophobicity can lead to the problem of remaining on the substrate after development, resulting in etching residues. The inventors discovered that etching residues can be reduced by using a compound (E) with a high solubility in alkaline aqueous solutions and an acidic group with a pKa of 5 or less. Furthermore, since a small swelling amount is advantageous for reducing side etch, the reactivity of the cured resist is also important. In particular, tetrazole undergoes radical cleavage in the short wavelength range of approximately 200 nm, which increases the reactivity, particularly at the copper interface (resist bottom) where these compounds are abundant, thereby suppressing the swelling rate at the resist bottom and contributing to low side etch. On the other hand, dye color development is favorable for the visibility of exposed areas. When an inspection machine or the like reads alignment markers for exposure, a high contrast between exposed and unexposed areas is advantageous because it makes them easier to recognize. It is believed that the compound (E) having an acidic group with a pKa of 5 or less that reacts during exposure stabilizes the cation of the dye, preferably leuco crystal violet (DMA), resulting in good color development and good exposure contrast.

[0016] <(A) Alkali-Soluble Polymer> The (A) alkali-soluble polymer is preferably one obtained by polymerizing at least one kind of first monomer described below, and more preferably one obtained by copolymerizing at least one kind of first monomer with at least one kind of second monomer described below.

[0017] The first monomer is a monomer containing a carboxyl group in the molecule. Examples of the first monomer include (meth)acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, and maleic acid half ester. Among these, (meth)acrylic acid is particularly preferred. In this specification, "(meth)acrylic" means acrylic and methacrylic, and "(meth)acrylate" means "acrylate" and "methacrylate."

[0018] The copolymerization ratio of the first monomer in the alkali-soluble polymer (A) is preferably 10% by mass to 35% by mass, more preferably 15% by mass to 30% by mass, and even more preferably 16% by mass to 28% by mass, based on the total mass of all monomers.

[0019] The second monomer is non-acidic and has at least one polymerizable unsaturated group in the molecule. Examples of the second monomer include (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and benzyl (meth)acrylate; esters of vinyl alcohol such as vinyl acetate; and (meth)acrylonitrile, styrene, and polymerizable styrene derivatives (e.g., methylstyrene, vinyltoluene, tert-butoxystyrene, acetoxystyrene, 4-vinylbenzoic acid, styrene dimer, and styrene trimer). Among these, methyl (meth)acrylate, n-butyl (meth)acrylate, styrene, 2-ethylhexyl (meth)acrylate, and benzyl (meth)acrylate are preferred, with benzyl (meth)acrylate being particularly preferred from the viewpoint of suppressing side etching.

[0020] The copolymerization ratio of the second monomer in the alkali-soluble polymer (A) is preferably 70% by mass to 90% by mass, more preferably 70% by mass to 85% by mass, and even more preferably 72% by mass to 84% by mass, based on the total mass of all monomers constituting the copolymer that becomes the alkali-soluble polymer (A).

[0021] In this embodiment, from the viewpoint of improving the resolution of the resist pattern, the alkali-soluble polymer (A) preferably contains an aromatic ring in its molecular structure, and more preferably has an aromatic group in a side chain of the structure.

[0022] The alkali-soluble polymer (A) having an aromatic group in its side chain can be prepared by using a compound having an aromatic group as at least one of the first and second monomers. Examples of the monomer having an aromatic group include (meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate, as well as phenoxy polyethylene glycol (meth)acrylate, styrene, cinnamic acid, and polymerizable styrene derivatives (e.g., methylstyrene, vinyltoluene, tert-butoxystyrene, acetoxystyrene, 4-vinylbenzoic acid, styrene dimer, and styrene trimer). From the viewpoint of suppressing side etching, (meth)acrylic acid aralkyl esters and styrene are preferred, with benzyl (meth)acrylate being particularly preferred.

[0023] The copolymerization ratio of the compound having an aromatic group is preferably 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more, based on the total mass of all monomers. From the viewpoint of maintaining alkali solubility, the copolymerization ratio of the compound having an aromatic group is preferably 95% by mass or less, more preferably 90% by mass or less.

[0024] In this embodiment, the alkali-soluble polymer (A) can be prepared by a known polymerization method, preferably addition polymerization, more preferably radical polymerization, of one or more monomers selected from the first monomer and the second monomer described above.

[0025] The acid equivalent of the alkali-soluble polymer (A) (when multiple types of copolymers are contained, the acid equivalent of the entire mixture) is preferably 100 or more from the viewpoint of the development resistance of the photosensitive resin layer and the resolution and adhesion of the resist pattern, and is preferably 600 or less from the viewpoint of the developability and strippability of the photosensitive resin layer. The acid equivalent of the alkali-soluble polymer (A) is more preferably 200 to 500, and even more preferably 250 to 450.

[0026] The weight-average molecular weight (hereinafter sometimes abbreviated as "Mw") of the alkali-soluble polymer (A) (when multiple types of alkali-soluble polymers are used in combination, this refers to the overall Mw of all of them) is preferably 5,000 to 500,000, more preferably 5,000 to 100,000, and even more preferably 10,000 to 65,000. The dispersity (Mw / Mn), which is the ratio of the weight-average molecular weight to the number-average molecular weight (hereinafter sometimes abbreviated as "Mn") (when multiple types of alkali-soluble polymers are used in combination, this refers to the overall dispersity), is preferably 1.0 to 6.0, more preferably 1.5 to 5.0, even more preferably 2.0 to 5.0, even more preferably 2.5 to 4.5, and particularly preferably 3.0 to 4.2. It is preferable that the weight average molecular weight and dispersity of the alkali-soluble polymer (A) be within the above ranges in order to obtain suitable developability, high coating strength, and uniformity of the resist thickness.

[0027] When multiple types of alkali-soluble polymers are used in combination as the alkali-soluble polymer (A), it is particularly preferable that they contain: (A-1) an alkali-soluble polymer having a Mw of less than 50,000, and (A-2) an alkali-soluble polymer having a Mw of 50,000 or more.

[0028] The Mw of the alkali-soluble polymer (A-1) is more preferably 5,000 or more and less than 50,000, even more preferably 10,000 to 45,000, and particularly preferably 10,000 to 35,000. It is preferable that the Mw of the alkali-soluble polymer (A-1) be within this range from the viewpoint of achieving both developability and resolution. On the other hand, the Mw of the alkali-soluble polymer (A-2) is more preferably 50,000 to 100,000, even more preferably 50,000 to 75,000, and particularly preferably 50,000 to 65,000. It is preferable that the Mw of the alkali-soluble polymer (A-2) be within this range from the viewpoint of extending the product life when the photosensitive resin composition of this embodiment is applied to a photosensitive element (also referred to as a "dry film resist").

[0029] The content of the alkali-soluble polymer component (A-1) relative to the total amount of solids in the photosensitive resin composition is preferably 3% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 25% by mass or less, and even more preferably 10% by mass or more and 20% by mass or less. Setting the use ratio of the component (A-1) within the above range is preferred from the viewpoint of achieving both high resolution and a small amount of side etching. The content of the alkali-soluble polymer component (A-2) relative to the total amount of solids in the photosensitive resin composition is preferably 5% by mass or more and 50% by mass or less, more preferably 15% by mass or more and 48% by mass or less, and even more preferably 18% by mass or more and 45% by mass or less. Setting the use ratio of the component (A-2) within the above range is preferred from the viewpoint of extending the product life when the photosensitive resin composition of this embodiment is applied to a photosensitive element (dry film resist).

[0030] The proportion of the alkali-soluble polymer (A) used in the photosensitive resin composition of this embodiment is preferably 25% by mass to 85% by mass, and more preferably 35% by mass to 75% by mass, based on the total amount of solids in the photosensitive resin composition. Setting the proportion of the alkali-soluble polymer (A) used within the above range is preferable from the viewpoints of resolution, developability, swelling of exposed areas in a developer, strippability of the resist pattern, and product life of the photosensitive element.

[0031] <(B) Compound Having an Ethylenically Unsaturated Double Bond> The (B) compound having an ethylenically unsaturated double bond is a compound that has polymerizability due to the presence of an ethylenically unsaturated double bond in its structure. Examples of such compounds include compounds in which (meth)acrylic acid is added to one end of a polyalkylene oxide, compounds in which (meth)acrylic acid is added to one end of a polyalkylene oxide and the other end is alkyl etherified or allyl etherified (first group of compounds); compounds in which (meth)acryloyl groups are added to both ends of an alkylene oxide chain, compounds in which ethylene oxide chains and propylene oxide chains are bonded randomly or in blocks and have (meth)acryloyl groups at both ends of the alkylene oxide chain, modified bisphenol A compounds (second group of compounds); and compounds in which three or more (meth)acryloyl groups are present in one molecule (third group of compounds).

[0032] Specific examples of other compounds in the first group include phenoxyhexaethylene glycol mono(meth)acrylate, which is a (meth)acrylate of a compound in which polyethylene glycol is added to a phenyl group; 4-normal nonylphenoxyheptaethylene glycol dipropylene glycol (meth)acrylate, which is a (meth)acrylate of a compound in which polypropylene glycol to which an average of 2 moles of propylene oxide has been added and polyethylene glycol to which an average of 7 moles of ethylene oxide has been added are added to nonylphenol; 4-normal nonylphenoxypentaethylene glycol monopropylene glycol (meth)acrylate, which is a (meth)acrylate of a compound in which polypropylene glycol to which an average of 1 mole of propylene oxide has been added and polyethylene glycol to which an average of 5 moles of ethylene oxide has been added to nonylphenol; and 4-normal nonylphenoxyoctaethylene glycol (meth)acrylate (e.g., M-114, manufactured by Toagosei Co., Ltd.), which is an acrylate of a compound in which polyethylene glycol to which an average of 8 moles of ethylene oxide has been added is added to nonylphenol.

[0033] Specific examples of the other compounds in the second group include tetraethylene glycol di(meth)acrylate, pentaethylene glycol di(meth)acrylate, hexaethylene glycol di(meth)acrylate, heptaethylene glycol di(meth)acrylate, octaethylene glycol di(meth)acrylate, nonaethylene glycol di(meth)acrylate, decaethylene glycol di(meth)acrylate, polyethylene glycol (meth)acrylates such as compounds having (meth)acryloyl groups at both ends of a 12-mol ethylene oxide chain; polypropylene glycol di(meth)acrylate; polybutylene glycol di(meth)acrylate; and the like. Examples of polyalkylene oxide di(meth)acrylate compounds containing ethylene oxide groups and propylene oxide groups include dimethacrylates of glycols in which an average of 3 moles of ethylene oxide have been added to each end of polypropylene glycol to which an average of 12 moles of propylene oxide have been added, and dimethacrylates of glycols in which an average of 15 moles of ethylene oxide have been added to each end of polypropylene glycol to which an average of 18 moles of propylene oxide have been added. Other examples include compounds in which polyalkylene glycols in which alkylene oxide has been added to bisphenol A have ethylenically unsaturated double bonds at both ends.

[0034] Among the compounds of the second group, it is preferable to use a compound obtained by modifying bisphenol A, which has an ethylenically unsaturated double bond at both ends of a polyalkylene glycol obtained by adding an alkylene oxide to bisphenol A, from the viewpoint of resolution and adhesion. The ethylenically unsaturated double bond in this compound is preferably contained in the compound in the form of being contained in a (meth)acryloyl group. For modifying bisphenol A by adding an alkylene oxide, for example, ethylene oxide modification, propylene oxide modification, butylene oxide modification, pentylene oxide modification, hexylene oxide modification, etc. are known. A compound obtained by adding ethylene oxide to bisphenol A and having a (meth)acryloyl group at both ends of a polyalkylene glycol is preferred.

[0035] Examples of such compounds include 2,2-bis(4-((meth)acryloxydiethoxy)phenyl)propane (e.g., NK Ester BPE-200 manufactured by Shin-Nakamura Chemical Co., Ltd.), 2,2-bis(4-((meth)acryloxytriethoxy)phenyl)propane, 2,2-bis(4-((meth)acryloxytetraethoxy)phenyl)propane, and 2,2-bis(4-((meth)acryloxypentaethoxy)phenyl)propane (e.g., NK Ester BPE-500 manufactured by Shin-Nakamura Chemical Co., Ltd.). Furthermore, ethylene oxide-modified and propylene oxide-modified compounds are also preferred, such as a di(meth)acrylate of a polyalkylene glycol in which an average of 2 moles of propylene oxide and an average of 6 moles of ethylene oxide are added to both ends of bisphenol A, or a di(meth)acrylate of a polyalkylene glycol in which an average of 2 moles of propylene oxide and an average of 15 moles of ethylene oxide are added to both ends of bisphenol A. From the viewpoint of improving resolution, adhesion, and flexibility, the number of moles of ethylene oxide and propylene oxide in the compound having (meth)acryloyl groups at both ends obtained by alkylene oxide-modifying bisphenol A is preferably 1 mole or more and 60 moles or less, more preferably 4 moles or more and 40 moles or less, and even more preferably 5 moles or more and 20 moles or less.

[0036] The compounds in the third group can be obtained by (meth)acrylating an alcohol obtained by adding an alkyleneoxy group, such as an ethyleneoxy group, a propyleneoxy group, or a butyleneoxy group, to a central skeleton having 3 or more moles of groups capable of adding an alkyleneoxy group in the molecule. Examples of compounds that can form the central skeleton include glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and an isocyanurate ring. More specifically, examples include triacrylate modified with 3 moles of ethylene oxide (EO), triacrylate modified with 6 moles of EO, triacrylate modified with 9 moles of EO, and triacrylate modified with 12 moles of EO. Examples of such compounds include glycerin triacrylate modified with 3 moles of EO (e.g., A-GLY-3E manufactured by Shin-Nakamura Chemical Co., Ltd.), glycerin triacrylate modified with 9 moles of EO (e.g., A-GLY-9E manufactured by Shin-Nakamura Chemical Co., Ltd.), glycerin triacrylate modified with 6 moles of EO and 6 moles of propylene oxide (PO) (A-GLY-0606PE), glycerin triacrylate modified with 9 moles of EO and 9 moles of PO (A-GLY-0909PE), etc. Further examples include pentaerythritol tetraacrylate modified with 4 moles of EO (e.g., SR-494 manufactured by Sartomer Japan Co., Ltd.), pentaerythritol tetraacrylate modified with 35 moles of EO (e.g., NK Ester ATM-35E manufactured by Shin-Nakamura Chemical Co., Ltd.), etc.

[0037] The compound having an ethylenically unsaturated double bond can also include an isocyanurate compound. Specific examples of such compounds include ethoxylated isocyanuric acid tri(meth)acrylate, ε-caprolactone-modified tris(2-(meth)acryloxyethyl)isocyanurate, triallyl isocyanurate, and compounds represented by the following formula: and (EO)-modified isocyanurate-derived tri(meth)acrylate (ethylene oxide adduct with an average of 27 mol). Commercially available products such as UA-7100 and A-9300-1CL (both manufactured by Shin-Nakamura Chemical Co., Ltd.) and Aronix M-327 (manufactured by Toagosei Co., Ltd.) can be used as such compounds.

[0038] Examples of compounds having a urethane bond and an ethylenically unsaturated double bond include urethane compounds of hexamethylene diisocyanate, tolylene diisocyanate, or a diisocyanate compound (e.g., 2,2,4-trimethylhexamethylene diisocyanate) with a compound having a hydroxyl group and a (meth)acrylic group in one molecule (e.g., 2-hydroxypropyl acrylate, oligopropylene glycol monomethacrylate). A specific example is a reaction product of hexamethylene diisocyanate and oligopropylene glycol monomethacrylate (manufactured by NOF Corporation, Blemmer PP1000).

[0039] Examples of compounds having a phthalic acid structure and an ethylenically unsaturated double bond include γ-chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-o-phthalate and β-hydroxyalkyl-β'-(meth)acryloyloxyalkyl-o-phthalate.

[0040] In addition, (B) the compound having an ethylenically unsaturated double bond may include tricyclodecane di(meth)acrylate and (2,2-bis{4-(methacryloxypentaethoxy)cyclohexyl}propane, etc.

[0041] The photosensitive resin composition of this embodiment preferably contains a compound modified with bisphenol A. The proportion of the bisphenol A modified compound used in the photosensitive resin composition of this embodiment is preferably 12% by mass to 45% by mass, more preferably 17% by mass to 40% by mass, and even more preferably 20% by mass to 40% by mass, relative to the total mass of the solid content of the photosensitive resin composition. Setting the proportion within this range is suitable from the viewpoint of obtaining a photosensitive resin composition that has an excellent balance between resolution and developability.

[0042] The proportion of the compound (B) having an ethylenically unsaturated double bond relative to the total solid mass of the photosensitive resin composition is preferably 5% by mass to 70% by mass. A ratio of 5% by mass or more is preferred from the viewpoints of sensitivity, resolution, and adhesion, and a ratio of 15% by mass or more is more preferred, and a ratio of 20% by mass or more is even more preferred. On the other hand, a ratio of 70% by mass or less is preferred from the viewpoint of suppressing edge fuse and delayed peeling of the cured resist, and a ratio of 60% by mass or less is more preferred.

[0043] <(C) Photopolymerization Initiator> Examples of the (C) photopolymerization initiator include a hexaarylbiimidazole compound, an N-aryl-α-amino acid compound, a quinone compound, an aromatic ketone compound, an acetophenone compound, an acylphosphine oxide compound, a benzoin compound, a benzoin ether compound, a dialkyl ketal compound, a thioxanthone compound, a dialkylaminobenzoic acid ester compound, an oxime ester compound, an acridine compound, a pyrazoline derivative, an N-arylamino acid ester compound, and a halogen compound.

[0044] Examples of the hexaarylbiimidazole compound include 2-(o-chlorophenyl)-4,5-diphenylbiimidazole, 2,2',5-tris-(o-chlorophenyl)-4-(3,4-dimethoxyphenyl)-4',5'-diphenylbiimidazole, 2,4-bis-(o-chlorophenyl)-5-(3,4-dimethoxyphenyl)-diphenylbiimidazole, 2,4,5-tris-(o-chlorophenyl)-diphenylbiimidazole, and 2-(o-chlorophenyl)-bis-4,5-(3,4-dimethoxyphenyl)-biimidazo. 2,2'-bis-(2-fluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3-difluoromethylphenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,5-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazo 2,2'-bis-(2,6-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,4-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole nyl)-biimidazole, 2,2'-bis-(2,4,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,4,5-tetrafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,4,6-tetrafluorophenyl)-4,4',5,Examples include 5'-tetrakis-(3-methoxyphenyl)-biimidazole and 2,2'-bis-(2,3,4,5,6-pentafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole. Among these, 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer is preferred from the viewpoints of high sensitivity, resolution, and adhesion.

[0045] Examples of N-aryl-α-amino acid compounds include N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, etc. N-phenylglycine is particularly preferred due to its high sensitizing effect.

[0046] Examples of quinone compounds include 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, and 3-chloro-2-methylanthraquinone.

[0047] Examples of aromatic ketone compounds include benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, etc. Examples of acetophenone compounds include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-(4-dodecylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propanone-1. Commercially available acetophenone compounds include, for example, Irgacure-907, Irgacure-369, and Irgacure-379 manufactured by Ciba Specialty Chemicals Inc. From the viewpoint of adhesion, 4,4'-bis(diethylamino)benzophenone is preferred.

[0048] Examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, etc. Commercially available acylphosphine oxide compounds include Lucirin TPO manufactured by BASF and Irgacure-819 manufactured by Ciba Specialty Chemicals.

[0049] Examples of benzoin compounds and benzoin ether compounds include benzoin, benzoin ethyl ether, benzoin phenyl ether, methylbenzoin, and ethylbenzoin. Examples of dialkyl ketal compounds include benzyl dimethyl ketal and benzyl diethyl ketal. Examples of thioxanthone compounds include 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone. Examples of dialkylaminobenzoic acid ester compounds include ethyl dimethylaminobenzoate, ethyl diethylaminobenzoate, ethyl-p-dimethylaminobenzoate, and 2-ethylhexyl-4-(dimethylamino)benzoate.

[0050] Examples of oxime ester compounds include 1-phenyl-1,2-propanedione-2-O-benzoyloxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime, etc. Commercially available oxime ester compounds include CGI-325, Irgacure-OXE01, and Irgacure-OXE02 manufactured by Ciba Specialty Chemicals.

[0051] As the acridine compound, 1,7-bis(9,9'-acridinyl)heptane or 9-phenylacridine is preferred in terms of sensitivity, resolution, availability, etc.

[0052] From the viewpoints of adhesion and rectangularity of the resist pattern, the pyrazoline derivatives are preferably 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-butyl-phenyl)-pyrazoline, and 1-phenyl-3-(4-biphenyl)-5-(4-tert-octyl-phenyl)-pyrazoline.

[0053] Examples of the ester compound of N-arylamino acid include methyl ester of N-phenylglycine, ethyl ester of N-phenylglycine, n-propyl ester of N-phenylglycine, isopropyl ester of N-phenylglycine, 1-butyl ester of N-phenylglycine, 2-butyl ester of N-phenylglycine, tert-butyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, hexyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, and octyl ester of N-phenylglycine.

[0054] Examples of halogen compounds include amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, methylene bromide, tribromomethylphenylsulfone, carbon tetrabromide, tris(2,3-dibromopropyl)phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, chlorinated triazine compounds, and diaryliodonium compounds, with tribromomethylphenylsulfone being particularly preferred.

[0055] The proportion of the photopolymerization initiator (C) used in the photosensitive resin composition of this embodiment is preferably 0.01% by mass to 20% by mass, and more preferably 0.5% by mass to 10% by mass, based on the total mass of the solids in the photosensitive resin composition. By using the photopolymerization initiator (C) in this range, sufficient sensitivity can be obtained, light can be sufficiently transmitted to the bottom of the resist, high resolution can be obtained, and a photosensitive resin composition that is well balanced with the amount of side etching in the conductor pattern can be obtained.

[0056] It is preferable to use a hexaarylbisimidazole compound as the (C) photopolymerization initiator. In this case, the proportion of the hexaarylbisimidazole compound used is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass to 5% by mass, relative to the total mass of the solid contents of the photosensitive resin composition.

[0057] As the (C) photopolymerization initiator, it is particularly preferable to use an aromatic ketone compound and a hexaarylbisimidazole compound in combination. In this case, the proportion of the aromatic ketone compound used is preferably 0.5 mass% or less, more preferably 0.01 mass% to 0.4 mass%, based on the total mass of the solid contents of the photosensitive resin composition. The proportion of the hexaarylbisimidazole compound used is preferably 0.1 mass% to 10 mass%, more preferably 0.5 mass% to 5 mass%, based on the total mass of the solid contents of the photosensitive resin composition.

[0058] <(D) Dye> The photosensitive resin composition of this embodiment contains a dye (D). When the photosensitive resin composition contains a dye, the exposed portion develops a color, which is preferable in terms of visibility. Furthermore, when an inspection machine or the like reads an alignment marker for exposure, a greater contrast between the exposed portion and the unexposed portion is advantageous because it makes the marker easier to recognize. Dyes that exhibit a greater contrast between the exposed portion and the unexposed portion when combined with the compound (E) of this embodiment are preferably leuco dyes and fluoran dyes, and more preferably leuco dyes.

[0059] The leuco dye can be blended into the photosensitive resin composition of this embodiment to impart favorable color development and excellent release properties to the cured resist film. Specific examples of leuco dyes include leuco crystal violet (tris[4-(dimethylamino)phenyl]methane:DMA) and 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide. Of these, leuco crystal violet (DMA) is preferred.

[0060] From the viewpoint of contrast between exposed and unexposed areas, the proportion of the dye used in the photosensitive resin composition of this embodiment is preferably 0.01% by mass to 2% by mass, and more preferably 0.1% by mass to 1.5% by mass, relative to the total amount of solids in the photosensitive resin composition. By setting the proportion of the leuco dye used in this range, good color development and sensitivity can be achieved.

[0061] In this embodiment, the dye may include a base dye. Examples of base dyes include Basic Green 1 [CAS number (hereinafter the same): 633-03-4] (e.g., Aizen Diamond Green GH, trade name, manufactured by Hodogaya Chemical Co., Ltd.), Malachite Green oxalate [2437-29-8] (e.g., Aizen Malachite Green, trade name, manufactured by Hodogaya Chemical Co., Ltd.), Brilliant Green [633-03-4], Fuchsin [632-99-5], Methyl Violet [603-47-4], Methyl Violet 2B [8004-87-3], Crystal Violet [548-62-9], Methyl Green [82-94-0], Victoria Blue B [2580-56-5], Basic Blue 7 [2390-60-5] (e.g., Aizen Victoria Pure Blue BOH (trade name, manufactured by Hodogaya Chemical Co., Ltd.), Rhodamine B [81-88-9], Rhodamine 6G [989-38-8], Basic Yellow 2 [2465-27-2], etc. Among these, one or more selected from Basic Green 1, Malachite Green oxalate, and Basic Blue 7 are preferred, and Basic Green 1 is particularly preferred from the viewpoints of hue stability and exposure contrast.

[0062] The content of the base dye in the photosensitive resin composition of this embodiment is preferably 0.001% by mass to 3% by mass, more preferably 0.01% by mass to 2% by mass, and even more preferably 0.01% by mass to 1.2% by mass, relative to the total solid content of the photosensitive resin composition. By using the base dye in this range, good colorability can be obtained.

[0063] <(E) Compound Having a Specific Heterocyclic Structure> In this embodiment, the compound (E) is a compound that does not have an amino group, and has an acidic group with a pKa of 5 or less and a heterocyclic structure having four nitrogen atoms. The compound (E) is preferably a solid at room temperature (25°C).

[0064] The compound (E) is a compound represented by the following general formula (3).

[0065]

[0066] In general formula (3), R １ and R ２ are each independently selected from the group consisting of a hydrogen atom and an organic group having 1 to 20 carbon atoms, preferably independently selected from the group consisting of a hydrogen atom and an organic group having 1 to 10 carbon atoms, and more preferably independently selected from the group consisting of a hydrogen atom and an organic group having 1 to 3 carbon atoms. １ and R ２ At least one of R has an acidic group with a pKa of 5 or less. １ and / or R ２ is an organic group having an acidic group with a pKa of 5 or less, the "number of carbon atoms" refers to the total number of carbon atoms in the organic group including the number of carbon atoms in the acidic group with a pKa of 5 or less.

[0067] In the general formula (3), specific examples of the organic group having 1 to 20 carbon atoms include an octadecyl group, a heptadecyl group, a hexadecyl group, a pentadecyl group, a tetradecyl group, a tridecyl group, a dodecyl group, an undecyl group, and a decyl group.

[0068] In the general formula (3), specific examples of the organic group having 1 to 10 carbon atoms include a nonyl group, an octyl group, a heptyl group, a hexyl group, a pentyl group, and a butyl group.

[0069] In the general formula (3), specific examples of the organic group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an iso-propyl group.

[0070] In general formula (3), specific examples of the acidic group having a pKa of 5 or less include a carboxy group, a phosphate group, and a sulfonic acid group. From the viewpoints of excellent color development and low side etching, the acidic group is preferably a carboxy group.

[0071] When the compound (E) is a compound represented by the general formula (3), excellent color development and low side etching can be obtained.

[0072] From the viewpoint of excellent color development and low side etching, the compound represented by general formula (3) is preferably １ and R ２It is more preferable that one of R is an organic group having 1 to 3 carbon atoms and having an acidic group with a pKa of 5 or less, and the other is independently selected from the group consisting of a hydrogen atom and an organic group having 1 to 3 carbon atoms; １ and R ２ It is even more preferable that one of the groups is an organic group having 1 to 3 carbon atoms and having an acidic group with a pKa of 5 or less, and the other is a hydrogen atom.

[0073] Specific examples of the compound represented by general formula (3) include 1H-tetrazole-1-carboxylic acid, 1H-tetrazole-5-carboxylic acid, 1H-tetrazole-1-acetic acid, 1H-tetrazole-5-acetic acid, 1H-tetrazole-1-propionic acid, 1H-tetrazole-5-propionic acid, 5-methyl-1H-tetrazole-1-carboxylic acid, 1-methyl-1H-tetrazole-5-carboxylic acid, 5-methyl-1H-tetrazole-1-acetic acid, 1-methyl-1H-tetrazole-5-acetic acid, 5-methyl-1H-tetrazole-1-propionic acid, 1-methyl-1H-tetrazole-5-propionic acid, 5-ethyl-1H-tetrazole-1-carboxylic acid, 1-ethyl-1H-tetrazole-5-carboxylic acid, 5-ethyl-1H-tetrazole-1-acetic acid, 1-ethyl-1H-tetrazole-5-acetic acid, 5-ethyl-1H-tetrazole-1-propionic acid, 1-ethyl-1H-tetrazole-5-propionic acid, 5-propyl-1H-tetrazole-1-carboxylic acid, 1-propyl-1H-tetrazole-5-carboxylic acid, 5-propyl-1H-tetrazole-1-acetic acid, 1-propyl -1H-tetrazole-5-acetic acid, 5-propyl-1H-tetrazole-1-propionic acid, 1-propyl-1H-tetrazole-5-propionic acid, 1-octadecyl-1H-tetrazole-5-acetic acid, 1-heptadecyl-1H-tetrazole-5-acetic acid, 1-hexadecyl-1H-tetrazole-5-acetic acid, 1-pentadecyl-1H-tetrazole-5-acetic acid, 1-tetradecyl-1H-tetrazole-5-acetic acid, 1-tridecyl-1H-tetrazole-5-acetic acid, 1-dodecyl-1H-tetrazole-5-acetic acid, 1-undecyl-1H -tetrazole-5-acetic acid, 1-decyl-1H-tetrazole-5-acetic acid, 1-nonyl-1H-tetrazole-5-acetic acid, 1-octa-1H-tetrazole-5-acetic acid, 1-hepta-1H-tetrazole-5-acetic acid, 1-hexa-1H-tetrazole-5-acetic acid, 1-penta-1H-tetrazole-5-acetic acid, 1-butyl-1H-tetrazole-5-acetic acid, 1-octadecyl-1H-tetrazole-5-propionic acid, 1-heptadecyl-1H-tetrazole-5-propionic acid, 1-hexadecyl-1H-tetrazole-5-propionic acid,Examples of the tetrazole-5-propionic acid include 1-pentadecyl-1H-tetrazole-5-propionic acid, 1-tetradecyl-1H-tetrazole-5-propionic acid, 1-tridecyl-1H-tetrazole-5-propionic acid, 1-dodecyl-1H-tetrazole-5-propionic acid, 1-undecyl-1H-tetrazole-5-propionic acid, 1-decyl-1H-tetrazole-5-propionic acid, 1-nonyl-1H-tetrazole-5-propionic acid, 1-octa-1H-tetrazole-5-propionic acid, 1-hepta-1H-tetrazole-5-propionic acid, 1-hexa-1H-tetrazole-5-propionic acid, 1-penta-1H-tetrazole-5-propionic acid, and 1-butyl-1H-tetrazole-5-propionic acid. Among these, from the viewpoints of excellent color development and low side etching, 1H-tetrazole-1-acetic acid and 1H-tetrazole-5-acetic acid are preferred as the compound represented by general formula (3), and 1H-tetrazole-5-acetic acid is more preferred.

[0074] From the viewpoints of excellent color development and low side etching, the content of compound (E) in the photosensitive resin composition may be in the range of 0.001% by mass to 5% by mass, preferably 0.001% by mass to 0.5% by mass, more preferably 0.001% by mass to 0.3% by mass, even more preferably 0.001% by mass to 0.2% by mass, and still more preferably 0.001% by mass to 0.1% by mass, relative to the total amount of solids in the photosensitive resin composition. The lower limit of the content of compound (E) in the photosensitive resin composition may be 0.01% by mass, 0.02% by mass, or 0.03% by mass, relative to the total amount of solids in the photosensitive resin composition.

[0075] <Other Components> The photosensitive resin composition of the present embodiment may contain only the components (A) to (E) described above, or may contain other components in addition to these. Examples of other components that can be used here include stabilizers.

[0076] The stabilizer is preferred from the viewpoint of improving the thermal stability or storage stability, or both, of the photosensitive resin composition. Examples of the stabilizer include at least one compound selected from the group consisting of a radical polymerization inhibitor, a benzotriazole compound, a carboxybenzotriazole compound, and an alkylene oxide compound having a glycidyl group. These may be used alone or in combination of two or more.

[0077] Examples of radical polymerization inhibitors include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], nitrosophenylhydroxyamine aluminum salt (e.g., aluminum salt with 3 moles of nitrosophenylhydroxylamine added), and diphenylnitrosamine. Among these, triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate] and aluminum salt with 3 moles of nitrosophenylhydroxylamine added are preferred. These can be used alone or in combination of two or more.

[0078] Examples of benzotriazole compounds include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-tolyltriazole, bis(N-2-hydroxyethyl)aminomethylene-1,2,3-benzotriazole, and a 1:1 mixture of 1-(2-di-n-butylaminomethyl)-5-carboxylbenzotriazole and 1-(2-di-n-butylaminomethyl)-6-carboxylbenzotriazole. Among these, a 1:1 mixture of 1-(2-di-n-butylaminomethyl)-5-carboxylbenzotriazole and 1-(2-di-n-butylaminomethyl)-6-carboxylbenzotriazole is preferred. These compounds can be used alone or in combination of two or more.

[0079] Examples of carboxybenzotriazole compounds include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, N-(N,N-di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, and N-(N,N-di-2-ethylhexyl)aminoethylenecarboxybenzotriazole. These can be used alone or in combination of two or more.

[0080] Examples of alkylene oxide compounds having a glycidyl group include neopentyl glycol diglycidyl ether (e.g., Epolite 1500NP manufactured by Kyoeisha Chemical Co., Ltd.), nonaethylene glycol diglycidyl ether (e.g., Epolite 400E manufactured by Kyoeisha Chemical Co., Ltd.), bisphenol A-propylene oxide 2-mol adduct diglycidyl ether (e.g., Epolite 3002 manufactured by Kyoeisha Chemical Co., Ltd.), and 1,6-hexanediol diglycidyl ether (e.g., Epolite 1600 manufactured by Kyoeisha Chemical Co., Ltd.). These compounds may be used alone or in combination of two or more.

[0081] In this embodiment, the total content of the radical polymerization inhibitor, benzotriazole compound, carboxybenzotriazole compound, and alkylene oxide compound having a glycidyl group in the photosensitive resin composition is preferably in the range of 0.001% by mass to 3% by mass, more preferably in the range of 0.05% by mass to 1.5% by mass. This total content is preferably 0.001% by mass or more from the viewpoint of imparting good storage stability to the photosensitive resin composition, and is preferably 3% by mass or less from the viewpoint of maintaining the sensitivity of the photosensitive resin layer.

[0082] [Photosensitive Resin Composition Preparation] In this embodiment, a photosensitive resin composition preparation can be prepared by adding a solvent to the photosensitive resin composition described above. Suitable solvents for use here include ketones such as methyl ethyl ketone (MEK); and alcohols such as methanol, ethanol, and isopropyl alcohol. It is preferable to prepare the photosensitive resin composition preparation by adding a solvent to the photosensitive resin composition so that the viscosity of the photosensitive resin composition preparation is 500 mPa·sec to 4,000 mPa·sec at 25°C.

[0083] [Photosensitive Element] The photosensitive element (also referred to as a dry film resist) of this embodiment includes a support and a photosensitive resin composition layer formed on the support from the photosensitive resin composition of this embodiment. If necessary, the photosensitive element of this embodiment may have a protective layer on the surface of the photosensitive resin composition layer opposite to the support.

[0084] [Support] The support is preferably a transparent substrate (film substrate, hereinafter also referred to as "support film") that transmits light emitted from the exposure light source. Examples of such support films include polyethylene terephthalate films, polyvinyl alcohol films, polyvinyl chloride films, vinyl chloride copolymer films, polyvinylidene chloride films, vinylidene chloride copolymer films, polymethyl methacrylate copolymer films, polystyrene films, polyacrylonitrile films, styrene copolymer films, polyamide films, and cellulose derivative films. These films may also be stretched as needed. The haze of the support is preferably 0.01% to 5.0%, more preferably 0.01% to 3.5%, even more preferably 0.01% to 2.5%, and even more preferably 0.01% to 1.0%. A thinner support is advantageous in terms of image formation and economy, but strength must be maintained. Taking both of these factors into consideration, a support having a thickness of 10 to 30 μm is preferably used.

[0085] [Photosensitive Resin Composition Layer] The photosensitive resin composition layer in the photosensitive element of this embodiment is a layer made of the photosensitive resin composition of this embodiment described above. If the photosensitive resin composition used to form the photosensitive resin composition layer contains a solvent, the solvent is preferably removed in the photosensitive resin composition layer, but residual solvent is acceptable. The thickness of the photosensitive resin composition layer in the photosensitive element of this embodiment is preferably 5 to 100 μm, more preferably 5 to 50 μm. The thinner the thickness, the better the resolution, and the thicker the thickness, the better the film strength. Therefore, the thickness of the composition layer can be appropriately selected within the above range depending on the application.

[0086] [Protective Film] An important characteristic of the protective layer in the photosensitive element of this embodiment is that the adhesion strength with the photosensitive resin composition layer is sufficiently smaller than the adhesion strength between the support and the photosensitive resin composition layer, allowing for easy peeling. As the protective layer, for example, a polyethylene film, a polypropylene film, or the like can be preferably used, or a film with excellent peelability such as that disclosed in JP-A-59-202457 can be used. The thickness of the protective layer is preferably 10 to 100 μm, more preferably 10 to 50 μm.

[0087] [Method for Manufacturing Photosensitive Element] The photosensitive element of this embodiment can be manufactured by sequentially laminating a support, a photosensitive resin composition layer, and, if necessary, a protective layer. A known method can be used to laminate the support, photosensitive resin composition layer, and protective layer. For example, the photosensitive resin composition of this embodiment is prepared as the photosensitive resin composition preparation described above, and first coated on a support using a bar coater or roll coater and dried to form a photosensitive resin composition layer composed of the photosensitive resin composition on the support. Next, if necessary, a protective layer can be laminated on the formed photosensitive resin composition layer to manufacture a photosensitive element.

[0088] [Method for forming a resist pattern] A resist pattern can be formed on a substrate using the photosensitive element as described above. The method for forming a resist pattern includes, in the order described above, a laminating step of forming a photosensitive resin composition layer on a substrate using the photosensitive element of this embodiment, an exposure step of exposing the photosensitive resin composition layer to light, and a development step of removing the unexposed areas of the photosensitive resin composition layer with a developer to form a resist pattern.

[0089] In the method for forming a resist pattern of this embodiment, first, in the laminating step, a photosensitive resin composition layer is formed on a substrate using a laminator. Specifically, if the photosensitive element has a protective layer, the protective layer is peeled off, and then the photosensitive resin composition layer is laminated onto the surface of the substrate using a laminator under heat and pressure. Examples of materials for the substrate used include copper, stainless steel (SUS), glass, indium tin oxide (ITO), and flexible substrates on which a thin conductive film is laminated. Examples of the thin conductive film include ITO, copper, copper-nickel alloy, and silver; and examples of materials constituting the flexible substrate include polyethylene terephthalate (PET). The substrate may have through-holes to accommodate multilayer substrates.

[0090] The photosensitive element of this embodiment is suitably applicable to the manufacture of touch panel sensors by an etching method. Etching is commonly used to form wiring (conductor patterns) in touch panel sensors. As described above, touch panel sensors require the formation of much finer wiring than ordinary printed wiring boards. However, when etching methods using photosensitive elements in conventional technology are employed, the amount of side etching of the formed conductor pattern is large, limiting the product yield of touch panel sensor manufacture. However, the photosensitive element of this embodiment excels in reducing the amount of side etching, making it possible to manufacture touch panel sensors with a high yield.

[0091] Here, the photosensitive resin composition layer may be laminated on only one surface of the substrate, or may be laminated on both surfaces of the substrate as necessary. The heating temperature at this time is preferably 40°C to 160°C. By performing thermocompression bonding two or more times, the adhesion of the resulting resist pattern to the substrate is further improved. When performing thermocompression bonding two or more times, a two-stage laminator equipped with two rolls may be used, or the laminate of the substrate and the photosensitive resin composition layer may be repeatedly passed through the rolls to be compressed.

[0092] Next, in the exposure step, the photosensitive resin composition layer is exposed using an exposure machine. This exposure may be performed through the support without peeling it off, or may be performed after peeling off the support if necessary. By performing this patternwise exposure, a resist film (resist pattern) having a desired pattern can be obtained after the development step described below. The patternwise exposure may be performed by either a method of exposure through a photomask or a maskless exposure method. When exposure is performed through a photomask, the exposure dose is determined by the illuminance of the light source and the exposure time. The exposure dose may also be measured using an actinometer. In maskless exposure, a photomask is not used, and exposure is performed directly on the substrate using a drawing device. As the light source, a semiconductor laser with a wavelength of 350 nm to 410 nm, an ultra-high pressure mercury lamp, or the like is used. In maskless exposure, the drawing pattern is controlled by a computer, and the exposure dose is determined by the illuminance of the exposure light source and the movement speed of the substrate. The photosensitive element of this embodiment is preferably applied to a method of exposure through a photomask, since this maximizes the effects of improving resolution and reducing the amount of side etching.

[0093] Next, in the development step, the unexposed areas of the photosensitive resin composition layer are removed with a developer. After exposure, if there is a support on the photosensitive resin composition layer, it is preferable to remove it before subjecting the layer to the development step. In the development step, the unexposed areas are developed and removed using a developer consisting of an alkaline aqueous solution to obtain a resist image. The alkaline aqueous solution may be, for example, Na ２ CO ３ , K. ２ CO ３ The alkaline aqueous solution is selected depending on the properties of the photosensitive resin composition layer, but it is preferable to use an aqueous solution of Na with a concentration of 0.2% by mass to 2% by mass. ２ CO ３ It is preferable to use an aqueous solution. The alkaline aqueous solution may contain a surfactant, an antifoaming agent, a small amount of an organic solvent to promote development, etc. The temperature of the developer in the development step is preferably kept constant in the range of 18°C ​​to 40°C.

[0094] A resist pattern can be obtained by the above process. In some cases, a heating step at 100°C to 300°C may be further performed. By performing this heating step, it is possible to further improve chemical resistance. For heating, a suitable heating furnace using hot air, infrared rays, far infrared rays, or the like can be used.

[0095] [Method for forming a wiring board] The method for forming a wiring board in this embodiment includes, in the order described above, a laminating step of forming a photosensitive resin composition layer on a substrate using the photosensitive element of this embodiment, an exposure step of exposing the photosensitive resin composition layer to light, a development step of forming a resist pattern by removing unexposed areas of the photosensitive resin composition layer with a developer, a conductor pattern forming step of etching or plating the substrate on which the resist pattern has been formed, and a peeling step of peeling off the resist pattern. By the above method, a wiring board having a desired conductor pattern formed on a substrate can be obtained.

[0096] The laminating step, the exposing step, and the developing step are the same as those in the above-mentioned [Method for forming a resist pattern]. After forming a resist pattern by the above-mentioned method for forming a resist pattern, a wiring board having a conductive pattern formed on a substrate can be obtained by going through the following conductive pattern forming step and peeling step. In the conductive pattern forming step, a conductive pattern can be formed on the substrate surface (e.g., copper surface) exposed by the developing step on the substrate on which the resist pattern has been formed, using a known etching method or plating method.

[0097] The side etch amount of the resist pattern obtained using the photosensitive resin composition of this embodiment is preferably 5.5 μm or less, more preferably 5.4 μm or less, and even more preferably 5.3 μm or less. The top width of the copper line pattern is desirably 4.2 μm or more, more preferably 4.5 μm or more, and even more preferably 4.8 μm or more. This has the advantage of enabling the formation of fine wiring, which is preferable.

[0098] The photosensitive resin composition, photosensitive element, and method for forming a conductive pattern in this embodiment can be extremely suitably applied to the production of, for example, printed wiring boards, lead frames, substrates having a concave-convex pattern, semiconductor packages, touch panel sensors, and the like.

[0099] [Touch Panel Sensor] The photosensitive resin composition, photosensitive element, and method for forming a conductor pattern according to this embodiment are particularly suitable for producing a touch panel sensor. The touch panel sensor is produced by forming lead wiring consisting of the conductor pattern formed by the above-described method on a flexible substrate having a sputtered copper layer. A liquid crystal display element, the above-described touch panel sensor, and glass are then laminated in this order to obtain a touch panel.

[0100] Unless otherwise specified, the evaluation values ​​of the various parameters described above are measured values ​​in accordance with the measurement methods in the examples described below.

[0101] Hereinafter, the present embodiment will be specifically described with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples.

[0102] <Weight-average molecular weight and dispersity> A sample was measured by gel permeation chromatography (GPC), and the weight-average molecular weight (Mw), number-average molecular weight (Mn), and dispersity (Mw / Mn) were calculated using a calibration curve of polystyrene (Shodex STANDARD SM-105 manufactured by Showa Denko K.K.). Specifically, measurements were carried out using a gel permeation chromatography manufactured by JASCO Corporation under the following conditions: Differential refractometer: RI-1530 Pump: PU-1580 Degasser: DG-980-50 Column oven: CO-1560 Column: KF-8025, KF-806M x 2, and KF-807 connected in series, in this order Eluent: THF

[0103] <Acid equivalent> Acid equivalent means the mass (grams) of a polymer having one equivalent of carboxyl groups in the molecule. The acid equivalent was measured by potentiometric titration using a Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd. and a 0.1 mol / L aqueous sodium hydroxide solution.

[0104] <Glass transition temperature> The glass transition temperature of the alkali-soluble polymer is determined by the Tg of each comonomer. ｉ The above-mentioned literature values ​​were used to calculate the value according to the Fox formula (I).

[0105] <Preparation of Photosensitive Element> The components shown in Table 1 were mixed, and methyl ethyl ketone (MEK) was further added to prepare a photosensitive resin composition with a solids concentration of 61% by mass. Table 2 also provides a description of each component shown in Table 1. The obtained photosensitive resin composition was uniformly applied using a bar coater to a 16 μm thick polyethylene terephthalate film (manufactured by Toray Industries, Inc., product name "FB40") serving as a support film, and then heated and dried for 5 minutes in a dryer controlled at 95°C to form a 5 μm thick photosensitive resin composition layer on the support film. A 33 μm thick polyethylene film (manufactured by Tamapoly Co., Ltd., product name "GF-858") serving as a protective layer was then attached to the surface of the photosensitive resin composition layer opposite the support film, thereby obtaining a photosensitive element.

[0106] <Substrate Used for Evaluation> A flexible substrate was used as the evaluation substrate, in which ITO and a thin copper film of 5 μm or less were vapor-deposited in this order on PET.

[0107] <Lamination> While peeling off the polyethylene film from the photosensitive element obtained in each Example or Comparative Example, the photosensitive element was laminated onto the substrate using a hot roll laminator (AL-70, manufactured by Asahi Kasei Corporation) under conditions of a roll temperature of 105°C, an air pressure of 0.35 MPa, and a lamination speed of 1.5 m / min.

[0108] <Exposure> Using a chrome glass mask, the resist was exposed with a parallel light exposure machine (OAK Corporation, HMW-801) at an exposure dose such that the top width of the resist obtained after exposure and development was 0 μm to +1 μm compared to the mask design value.

[0109] <Contrast> The polyethylene film was peeled off from the photosensitive element, and after 15 minutes of exposure at the above exposure dose, the contrast between the exposed and unexposed areas was measured from the polyethylene terephthalate side using a spectrometer (NF333, manufactured by Nippon Denshoku Industries Co., Ltd.). Contrast = Transmittance of exposed area (%) / Transmittance of unexposed area (%)

[0110] <Development> After peeling off the support film from the exposed photosensitive resin composition layer, the photosensitive resin composition layer was developed using an alkaline developer (manufactured by Fuji Kiko Co., Ltd., a dry film developer) with 1% by mass Na ２ CO ３ The aqueous solution was sprayed for twice the minimum developing time to dissolve and remove the unexposed portions of the photosensitive resin composition layer. After development, a water washing treatment was performed to obtain a substrate having a cured film for evaluation. The minimum developing time refers to the minimum time required for the unexposed portions of the photosensitive resin composition layer to be completely dissolved and removed.

[0111] <Adhesion> When an independent thin line having a length of 30 mm was measured under the above-mentioned development conditions, the minimum line width at which the pattern remained was taken as the adhesion.

[0112] <Side Etch Amount> To evaluate the side etch amount, a laminate substrate was used 15 minutes after the above <Lamination>. A line / space pattern of 10 μm / 10 μm was exposed to the laminate substrate, and then developed using the method described in the above <Development>. First, the resist bottom width Wb of the pattern was measured using an optical microscope. Next, the substrate with this line / space pattern was etched using a dip method with a hydrochloric acid concentration of 2% by mass, ferric chloride 2% by mass, and a temperature of 30°C for 70 seconds (Condition I) or 30 seconds (Condition II). After the etching, the cured film on the substrate was peeled off at 50°C using a 3% by mass aqueous NaOH solution as a stripper, and the top width Wt of the resulting copper line pattern was measured using an optical microscope. The side etch amount was then calculated using the following formula: Side etch (μm) = Wb - Wt.

[0113] <Uniformity of Copper Line Width> After development by the method described in <Development> above, the copper line was measured over a length of 100 mm to determine the outermost and innermost ends of the copper line, and evaluated according to the following criteria: ⊚: The distance from the outermost to the innermost end of the line was less than 0.2 μm; ◯: The distance from the outermost to the innermost end of the line was 0.2 μm or more and less than 0.5 μm; △: The distance from the outermost to the innermost end of the line was 0.5 μm or more.

[0114] Examples 1 to 5 and Comparative Examples 1 to 5 Table 1 shows the compositions of the photosensitive resin compositions used in the examples and comparative examples, and Table 2 shows the details of each component listed in Table 1. The blend amount of each component in Table 1 is in parts by mass converted to solid content. Table 1 summarizes the evaluation results of adhesion, side etch amount, uniformity of copper line width, and contrast performed using each photosensitive resin composition. In Table 1, all of Examples 1 to 5 showed a good balance in the evaluation items "side etch amount," "uniformity of copper line width," and "contrast," and each evaluation result was also good. In particular, Examples 2 and 4 showed good results despite the low content of compound (E) in the photosensitive resin composition.

[0115]

[0116]

[0117] The photosensitive resin composition of the present embodiment can be used, for example but not limited to, as a dry film for forming wiring, a color development aid for dyes, or an agent for preventing penetration of an etching solution between a resist and a substrate.

Claims

1. (A) an alkali-soluble polymer, (B) a compound having an ethylenically unsaturated double bond, (C) a photopolymerization initiator, (D) a dye, and (E) a compound represented by the following general formula (3): {In the formula, R １ and R ２ Each of R does not have an amino group and is independently selected from the group consisting of a hydrogen atom or an organic group having 1 to 20 carbon atoms, with the proviso that R １ and R ２ At least one of the above has an acidic group having a pKa of 5 or less.

2. In the formula, R １ and R ２ Each of R does not have an amino group and is independently selected from the group consisting of a hydrogen atom or an organic group having 1 to 3 carbon atoms, with the proviso that R １ and R ２ The photosensitive resin composition according to claim 1 , wherein at least one of the above has an acidic group having a pKa of 5 or less.

3. In the formula, R １ and R ２ None of the above has an amino group, and R １ and R ２ 3. The photosensitive resin composition according to claim 2, wherein one of the above is an organic group having 1 to 3 carbon atoms and having an acidic group having a pKa of 5 or less, and the other is a hydrogen atom.

4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the acidic group is any one of a carboxyl group, a phosphoric acid group, and a sulfonic acid group.

5. The photosensitive resin composition according to claim 4, wherein the acidic group is a carboxy group.

6. The photosensitive resin composition according to any one of claims 1 to 5, wherein the dye (D) is a leuco dye.

7. The photosensitive resin composition according to any one of claims 1 to 6, wherein the compound (E) is contained in an amount of 0.001 to 0.5 mass % based on the total amount of solids in the photosensitive resin composition.

8. The photosensitive resin composition according to any one of claims 1 to 7, wherein the compound (E) is a solid at 25°C.

9. The photosensitive resin composition according to any one of claims 1 to 8, wherein the alkali-soluble polymer (A) contains an aromatic ring in its molecular structure.

10. A photosensitive element comprising a support and a layer of the photosensitive resin composition according to any one of claims 1 to 9 formed on the support.